Schizoid personality disorder: Difference between revisions

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{{Short description|Mental condition involving asociality and diminished emotions}}
{{Redirect|Schizoid|the video game|Schizoid (video game)|the film|Schizoid (film)}}
{{Distinguish|Schizophrenia|Schizotypal personality disorder|Schizoaffective disorder|Antisocial personality disorder}}
{{Infobox medical condition (new)
{{Infobox medical condition (new)
| name = Schizoid personality disorder
| name = Schizoid personality disorder
| field = [[Psychiatry]], [[clinical psychology]]
| field = [[Psychiatry]], [[clinical psychology]]
| symptoms = Pervasive [[emotional detachment]], [[reduced affect display|reduced affect]], lack of close [[Friendship|friends]], [[apathy]], [[anhedonia]], unintentional insensitivity to [[social norm]]s, [[sexual abstinence]], preoccupation with [[Fantasy (psychology)|fantasy]],<ref name="ICD10Green" /> [[Glossary of psychiatry#Autistic thinking|autistic thinking]] without [[Psychosis|loss of skill to recognize reality]]<ref name="DSM-II">{{cite book|title=Diagnostic and Statistical Manual of Mental Disorders, 2nd Edition|date=1968|location=Washington, D. C.|page=42|author=American Psychiatric Association |isbn=978-0-89042-035-5 |url=https://dsm.psychiatryonline.org/doi/pdf/10.1176/appi.books.9780890420355.dsm-ii|doi=10.1176/appi.books.9780890420355.dsm-ii|doi-broken-date=31 July 2022}}</ref>
|specialty=
| complications =
| symptoms = Pervasive [[emotional detachment]], [[reduced affect display|reduced affect]], lack of close [[Friendship|friends]], [[apathy]], [[anhedonia]], unintentional insensitivity to [[social norm]]s, [[sexual abstinence]], preoccupation with [[Fantasy (psychology)|fantasy]],<ref name="ICD10Green" /> [[Glossary of psychiatry#Autistic thinking|autistic thinking]] without [[Psychosis|loss of skill to recognize reality]]<ref name="DSM-II">{{cite book |url=https://dsm.psychiatryonline.org/doi/book/10.1176/appi.books.9780890420355.dsm-ii |doi=10.1176/appi.books.9780890420355.dsm-ii |doi-broken-date=31 December 2022 |title=Diagnostic and Statistical Manual of Mental Disorders |series=DSM Library |edition=2nd |year=1968 |publisher=American Psychiatric Association |isbn=978-0-89042-035-5 }}{{pn|date=November 2022}}</ref>
| onset = Late childhood or adolescence<ref name="ICD10Green" />
| complications =
| duration = Life long
| onset = Late childhood or adolescence<ref name="ICD10Green" />
| types = Languid schizoid, remote schizoid, depersonalized schizoid, affectless schizoid ([[Theodore Millon|Millon]]'s subtypes)</ref>
| duration = Long term
| causes = Family history; cold, indifferent, or intrusive parenting; [[traumatic brain injury]]; low [[birth weight]]; [[prenatal nutrition|prenatal malnutrition]]
| types = Languid schizoid, remote schizoid, depersonalized schizoid, affectless schizoid ([[Theodore Millon|Millon]]'s subtypes)<ref name="Millon 11"/>
| risks = [[Family history (medicine)|Family history]]<ref name="ClusterA" />
| causes =
| diagnosis = Based on symptoms
| risks = [[Family history (medicine)|Family history]]<ref name="ClusterA" />
| differential = Other mental disorders with psychotic symptoms ([[schizophrenia]], [[delusional disorder]], and a [[Bipolar disorder|bipolar]] or [[Major depressive disorder|depressive disorder]] with psychotic features), personality change due to another medical condition, [[substance use disorder]]s, [[autism spectrum disorder]], other personality disorders and personality traits
| diagnosis = Based on symptoms
| prevention =
| differential = Other mental disorders with psychotic symptoms ([[schizophrenia]], [[delusional disorder]], and a [[Bipolar disorder|bipolar]] or [[Major depressive disorder|depressive disorder]] with psychotic features), personality change due to another medical condition, [[substance use disorder]]s, [[autism spectrum disorder]], other personality disorders and personality traits<ref name="DSM-5-Schizoid"/>
| treatment = [[Psychodynamic psychotherapy]]; [[Cognitive Behavioral Therapy]]
| prevention =
| medication = Not general practice but may include low dose [[benzodiazepine]]s, [[β-blockers]], [[nefazodone]], [[bupropion]]<ref name="SonnyJoseph" />
| treatment = Not yet studied.<ref name="Medline" />
| prognosis = Typically poor<ref name=":9" /><ref name=":12"/><ref name=":7"/>
| medication = Not general practice but may include low dose [[benzodiazepine]]s, [[β-blockers]], [[nefazodone]], [[bupropion]]<ref name="SonnyJoseph" />
| prognosis = Typically poor<ref name=":9" /><ref name=":12"/><ref name=":7"/>
| frequency = 0.8%<ref name="ClusterA" /><ref name=":9" /><ref name=":10" />
| pronounce = {{IPAc-en|ˈ|s|k|ɪ|t|s|ɔɪ|d|,_|ˈ|s|k|ɪ|d|z|ɔɪ|d|,_|ˈ|s|k|ɪ|z|ɔɪ|d|}}
| frequency = 0.8%<ref name="ClusterA" /><ref name=":9" /><ref name=":10" />
| synonym =
| image_size=
| image = Solitude.jpg
| pronounce = {{IPAc-en|ˈ|s|k|ɪ|t|s|ɔɪ|d|,_|ˈ|s|k|ɪ|d|z|ɔɪ|d|,_|ˈ|s|k|ɪ|z|ɔɪ|d|}}
| alt = Man sitting alone on a bench
| synonym=
| caption = People with schizoid personality disorder often prefer solitary activities.
| image = Solitude.jpg
| alt=
| caption = People with schizoid personality disorder often prefer solitary activities.
}}
}}
'''Schizoid personality disorder''' ({{IPAc-en|ˈ|s|k|ɪ|t|s|ɔɪ|d|,_|ˈ|s|k|ɪ|d|z|ɔɪ|d|,_|ˈ|s|k|ɪ|z|ɔɪ|d|}}, often abbreviated as '''SzPD''' or '''ScPD''') is a [[personality disorder]] characterized by a [[Asociality|lack of interest in social relationships]],<ref>{{Cite journal |last=Dierickx |first=Serafine |last2=Dierckx |first2=Eva |last3=Claes |first3=Laurence |last4=Rossi |first4=Gina |date=2022 |title=Measuring Behavioral Inhibition and Behavioral Activation in Older Adults: Construct Validity of the Dutch BIS/BAS Scales |url=http://journals.sagepub.com/doi/10.1177/10731911211000123 |journal=Assessment |language=en |volume=29 |issue=5 |pages=1061–1074 |doi=10.1177/10731911211000123 |issn=1073-1911 |via=[[SAGE publications]]}}</ref> a tendency toward a solitary or sheltered li{{Personality disorders sidebar}}fe style, secretiveness, emotional coldness, detachment, and [[apathy]]. Affected individuals may be unable to form intimate attachments to others and simultaneously possess a rich and elaborate but exclusively internal [[Fantasy (psychology)|fantasy world]].<ref name="Medline">{{cite web |last=[[MedlinePlus]] (2014) |title=Schizoid Personality Disorder |url=https://www.nlm.nih.gov/medlineplus/ency/article/000920.htm |url-status=live |archive-url=https://web.archive.org/web/20220914130520/https://medlineplus.gov/ency/article/000920.htm |archive-date=September 14, 2022 |website=[[MedlinePlus]] |publisher=National Library of Medicine}}</ref><ref>{{cite book |last1=Reber |first=Arthur |url=https://www.google.com/books/edition/The_Penguin_Dictionary_of_Psychology/BIpPEAAAQBAJ?hl=en |title=The Penguin Dictionary of Psychology |last2=Allen |first2=Rhianon |last3=Reber |first3=Emily |publisher=[[Penguin Books]] |year=2009 |isbn=978-014-103-024-1 |edition=4th |location=London; New York |page=706 |language=en |oclc=288985213 |author-link1=Arthur S. Reber |orig-date=1985}}</ref> Other associated features include [[stilted speech]], a [[Anhedonia|lack of deriving enjoyment]] from most activities, feeling as though one is an "observer" rather than a participant in life, an inability to tolerate emotional expectations of others, apparent indifference when praised or criticized, a degree of [[asexuality]], and idiosyncratic moral or political beliefs.<ref name="Akhtar">{{cite book |author=Salman Akhtar |url=https://books.google.com/books?id=bU0eAAAAQBAJ&pg=PA121 |title=Schizoid Personality Disorder: A Synthesis of Developmental, Dynamic, and Descriptive Features |journal=American Journal of Psychotherapy |year=1987 |isbn=9781461627685 |volume=41 |pages=499–518 |doi=10.1176/appi.psychotherapy.1987.41.4.499 |pmid=3324773 |access-date=2017-02-10 |archive-url=https://web.archive.org/web/20170731160223/https://books.google.de/books?id=bU0eAAAAQBAJ&pg=PA121 |archive-date=2017-07-31 |url-status=live |issue=4}}</ref> Symptoms typically start in late childhood or adolescence.<ref name="Medline" /> The cause of SzPD is uncertain, but there is some evidence of links and shared genetic risk between SzPD, other [[Personality disorder#Cluster A (odd or eccentric disorders)|cluster A personality disorders]], and [[schizophrenia]].<ref name=":27">{{Cite journal |last=Kendler |first=Kenneth S. |last2=Czajkowski |first2=Nikolai |last3=Tambs |first3=Kristian |last4=Torgersen |first4=Svenn |last5=Aggen |first5=Steven H. |last6=Neale |first6=Michael C. |last7=Reichborn-Kjennerud |first7=Ted |date=2006 |title=Dimensional representations of DSM-IV Cluster A personality disorders in a population-based sample of Norwegian twins: a multivariate study |url=https://www.cambridge.org/core/journals/psychological-medicine/article/abs/dimensional-representations-of-dsmiv-cluster-a-personality-disorders-in-a-populationbased-sample-of-norwegian-twins-a-multivariate-study/7FCB8A9197B4BB25A78ED768491581BB |url-status=live |journal=Psychological Medicine |language=en |volume=36 |issue=11 |pages=1583–1591 |doi=10.1017/S0033291706008609 |issn=1469-8978 |archive-url=https://web.archive.org/web/20220301170757/https://www.cambridge.org/core/journals/psychological-medicine/article/abs/dimensional-representations-of-dsmiv-cluster-a-personality-disorders-in-a-populationbased-sample-of-norwegian-twins-a-multivariate-study/7FCB8A9197B4BB25A78ED768491581BB |archive-date=March 1, 2022 |via=[[Cambridge Core]]}}</ref><ref>{{Cite journal |last=Arciniegas |first=David B. |date=2015 |title=Psychosis |url=https://journals.lww.com/continuum/Abstract/2015/06000/Psychosis.15.aspx |url-status=live |journal=CONTINUUM: Lifelong Learning in Neurology |language=en-US |volume=21 |issue=3 |pages=715 |doi=10.1212/01.CON.0000466662.89908.e7 |issn=1080-2371 |archive-url=https://web.archive.org/web/20220618044745/https://journals.lww.com/continuum/Abstract/2015/06000/Psychosis.15.aspx |archive-date=June 18, 2022}}</ref><ref>{{Cite journal |last=Kendler |first=Kenneth S. |last2=Myers |first2=John |last3=Torgersen |first3=Svenn |last4=Neale |first4=Michael C. |last5=Reichborn-Kjennerud |first5=Ted |date=2007 |title=The heritability of cluster A personality disorders assessed by both personal interview and questionnaire |url=https://www.cambridge.org/core/journals/psychological-medicine/article/abs/heritability-of-cluster-a-personality-disorders-assessed-by-both-personal-interview-and-questionnaire/12C9CFFF17A2070F77E01EB6548F3F27 |url-status=live |journal=Psychological Medicine |language=en |volume=37 |issue=5 |pages=655–665 |doi=10.1017/S0033291706009755 |issn=1469-8978 |archive-url=https://web.archive.org/web/20210608081740/https://www.cambridge.org/core/journals/psychological-medicine/article/abs/heritability-of-cluster-a-personality-disorders-assessed-by-both-personal-interview-and-questionnaire/12C9CFFF17A2070F77E01EB6548F3F27 |archive-date=June 8, 2022 |via=[[Cambridge Core]]}}</ref><ref>{{Cite journal |last=Raine |first=Adrian |last2=Allbutt |first2=John |year=1989 |title=Factors of schizoid personality |url=https://bpspsychub.onlinelibrary.wiley.com/doi/abs/10.1111/j.2044-8260.1989.tb00809.x?sid=nlm%3Apubmed |journal=British Journal of Clinical Psychology |volume=28 |issue=1 |pages=31-40 |doi=10.1111/j.2044-8260.1989.tb00809.x |via=[[Wiley Online Library]]}}</ref><ref>{{Cite journal |last=Collins |first=Lindsay M. |last2=Blanchard |first2=Jack J. |last3=Biondo |first3=Kara M. |date=2005-10-15 |title=Behavioral signs of schizoidia and schizotypy in social anhedonics |url=https://www.sciencedirect.com/science/article/pii/S0920996405001726 |url-status=live |journal=Schizophrenia Research |language=en |volume=78 |issue=2 |pages=309–322 |doi=10.1016/j.schres.2005.04.021 |issn=0920-9964 |via=[[Elsevier Science Direct]]}}</ref> Thus, SzPD is considered to be a "schizophrenia-like personality disorder".<ref name="ClusterA">{{cite journal |last1=Esterberg |first=Michelle |last2=Goulding |first2=Sandra |last3=Walker |first3=Elaine |year=2010 |title=Cluster A Personality Disorders: Schizotypal, Schizoid and Paranoid Personality Disorders in Childhood and Adolescence |journal=Journal of Psychopathology and Behavioral Assessment |volume=32 |issue=4 |pages=515–528 |doi=10.1007/s10862-010-9183-8 |pmc=2992453 |pmid=21116455 |via=[[PubMed]]}}</ref><ref name="CharneyNestler2005">{{Cite book |last=Charney |first=Dennis S. |url=https://books.google.com/books?id=en-mwwlzYqgC&newbks=0&printsec=frontcover&pg=PA240&hl=en |title=Neurobiology of Mental Illness |last2=Nestler |first2=Eric J. |date=2005-07-21 |publisher=Oxford University Press, USA |isbn=978-0-19-518980-3 |pages=240 |language=en}}</ref> It is diagnosed by clinical observation, and it can be very difficult to distinguish SzPD from other mental disorders or conditions (such as [[autism spectrum disorder]], with which it may sometimes overlap).<ref name=":17">{{Cite journal |last1=Lugnegård |first1=Tove |last2=Hallerbäck |first2=Maria Unenge |last3=Gillberg |first3=Christopher |date=May 2012 |title=Personality disorders and autism spectrum disorders: what are the connections? |url=https://www.sciencedirect.com/science/article/abs/pii/S0010440X11001325?via%3Dihub |url-status=live |journal=Comprehensive Psychiatry |volume=53 |issue=4 |pages=333–340 |doi=10.1016/j.comppsych.2011.05.014 |pmid=21821235 |archive-url=https://web.archive.org/web/20220815131056/https://www.sciencedirect.com/science/article/abs/pii/S0010440X11001325?via%3Dihub |archive-date=August 15, 2022 |via=[[Elsevier Science Direct]]}}</ref><ref name=":21">{{Cite journal |last=Cook |first=Michal L. |year=2019 |title=On the Continuity Between Autistic and Schizoid Personality Disorder Trait Burden: A Prospective Study in Adolescence |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6982569/ |url-status=live |journal=The Journal of Nervous and Mental Disease |volume=208 |issue=2 |pages=94–100 |doi=10.1097/NMD.0000000000001105 |pmc=6982569 |pmid=31856140 |archive-url=https://web.archive.org/web/20211127175938mp_/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6982569/pdf/nihms-1533812.pdf |archive-date=November 27, 2021 |via=[[PubMed]]}}</ref>
{{Personality disorders sidebar}}


The effectiveness of [[psychotherapeutic]] and [[pharmacological]] treatments for the disorder has yet to be empirically and systematically investigated. This is largely because people with SzPD rarely seek treatment for their condition.<ref name="Medline" /> Originally, low doses of [[atypical antipsychotics]] were also used to treat some symptoms of SzPD, but their use is no longer recommended.<ref name=":15">{{Cite journal |last=Thylstrup |first=Birgitte |last2=Hesse |first2=Morten |date=2009-04-01 |title=“I am not Complaining”—Ambivalence Construct in Schizoid Personality Disorder |url=https://psychotherapy.psychiatryonline.org/doi/10.1176/appi.psychotherapy.2009.63.2.147 |url-status=live |journal=American Journal of Psychotherapy |volume=63 |issue=2 |pages=147–167 |doi=10.1176/appi.psychotherapy.2009.63.2.147 |issn=0002-9564 |pmid=19711768 |archive-url=https://web.archive.org/web/20220314071415/https://psychotherapy.psychiatryonline.org/doi/10.1176/appi.psychotherapy.2009.63.2.147 |archive-date=March 14, 2022 |via=Psychiatry Online}}</ref> The [[substituted amphetamine]] [[bupropion]] may be used to treat associated [[anhedonia]].<ref name="SonnyJoseph">{{Cite book |last=Sonny |first=Joseph |url=https://www.google.com/books/edition/Personality_Disorders/KEoPC3_1AGAC?hl=en&gbpv |title=Personality Disorders: New Symptom-Focused Drug Therapy |publisher=Psychology Press |year=1997 |isbn=9780789001344 |pages=45–56 |language=en |chapter=Chapter 3, Schizoid Personality Disorder |chapter-url=https://books.google.com/books?id=KEoPC3_1AGAC&pg=PA45}}</ref> However, it is not general practice to treat SzPD with medications, other than for the short-term treatment of acute co-occurring disorders (e.g. [[Depression (mood)|depression]]).<ref name=":28">{{Cite web |date=August 17, 2017 |title=Schizoid personality disorder - Diagnosis and treatment - Mayo Clinic |url=https://www.mayoclinic.org/diseases-conditions/schizoid-personality-disorder/diagnosis-treatment/drc-20354419 |url-status=live |archive-url=https://web.archive.org/web/20220607183034/https://www.mayoclinic.org/diseases-conditions/schizoid-personality-disorder/diagnosis-treatment/drc-20354419 |archive-date=June 7, 2022 |access-date=2022-09-30 |website=www.mayoclinic.org |language=en}}</ref> Talk therapies such as [[cognitive behavioral therapy]] (CBT) may not be effective, because people with SzPD may have a hard time forming a good working relationship with a therapist.<ref name="Medline" />
<!-- Definition and symptoms -->
'''Schizoid personality disorder''' ({{IPAc-en|ˈ|s|k|ɪ|t|s|ɔɪ|d|,_|ˈ|s|k|ɪ|d|z|ɔɪ|d|,_|ˈ|s|k|ɪ|z|ɔɪ|d|}}, often abbreviated as '''SzPD''' or '''ScPD''') is a [[personality disorder]] characterized by a [[Asociality|lack of interest in social relationships]], a tendency toward a solitary or sheltered lifestyle, secretiveness, emotional coldness, detachment and [[apathy]]. Affected individuals may be unable to form intimate attachments to others and simultaneously possess a rich and elaborate but exclusively internal [[fantasy (psychology)|fantasy world]].<ref name="Medline">{{MedlinePlusEncyclopedia|000920|Schizoid personality disorder}}</ref><ref>{{cite book|title=The Penguin Dictionary of Psychology|publisher=[[Penguin Books]]|year=2009|isbn=9780141030241|edition=4th|location=London; New York|page=706|oclc=288985213|last1=Arthur S. Reber|author-link1=Arthur S. Reber|orig-date=1985}}</ref> Other associated features include [[stilted speech]], a [[Anhedonia|lack of deriving enjoyment]] from most activities, feeling as though one is an "observer" rather than a participant in life, an inability to tolerate emotional expectations of others, apparent indifference when praised or criticized, a degree of [[asexuality]] and idiosyncratic moral or political beliefs.<ref name="Akhtar">{{cite journal |last1=Akhtar |first1=Salman |title=Schizoid Personality Disorder: A Synthesis of Developmental, Dynamic, and Descriptive Features |journal=American Journal of Psychotherapy |date=October 1987 |volume=41 |issue=4 |pages=499–518 |doi=10.1176/appi.psychotherapy.1987.41.4.499 |pmid=3324773 }}</ref> Symptoms typically start in late childhood or adolescence.<ref name="Medline" />


SzPD is a poorly studied disorder, and there is little clinical data on SzPD because it is rarely encountered in clinical settings. Studies have generally reported a prevalence of less than 1%.<ref name="ClusterA" /><ref name=":10">{{Cite journal |last=Triebwasser |first=Joseph |last2=Chemerinski |first2=Eran |last3=Roussos |first3=Panos |last4=Siever |first4=Larry J. |date=2012-12-01 |title=Schizoid Personality Disorder |url=https://guilfordjournals.com/doi/10.1521/pedi.2012.26.6.919 |url-status=live |journal=Journal of Personality Disorders |volume=26 |issue=6 |pages=919–926 |doi=10.1521/pedi.2012.26.6.919 |issn=0885-579X |archive-url=https://web.archive.org/web/20220619085124/https://guilfordjournals.com/doi/10.1521/pedi.2012.26.6.919 |archive-date=June 19, 2022 |via=[[Guilford Press]]}}</ref><ref>{{cite book |title=Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (2013) |year=2013 |isbn=978-0-89042-555-8 |chapter=Schizoid Personality Disorder (pp. 652–655) |chapter-url=https://archive.org/details/diagnosticstatis0005unse |via=[[Internet Archive]] |chapter-url-access=registration}}</ref> It is more commonly diagnosed in males than in females.<ref name=":10" /> SzPD is linked to negative outcomes, including a significantly compromised [[quality of life]], reduced [[Global Assessment of Functioning|overall functioning]] even after 15 years, and one of the lowest levels of "life success" of all personality disorders (measured as "status, wealth and successful relationships").<ref name=":9">{{Cite book |last=Emmelkamp |first=Paul |url=https://books.google.com/books?id=RwNmAgAAQBAJ |title=Personality Disorders |last2=Kamphuis |first2=Jan |publisher=[[Taylor & Francis]] |isbn=978-131-783-477-9 |publication-date=December 19, 2013 |page=54 |language=en}}</ref><ref name=":122">{{Cite journal |last=Skodol |first=Andrew E. |author1-link=Andrew E. Skodol |year=2011 |title=Personality Disorder Types Proposed for DSM-5 |url=https://www.researchgate.net/publication/51019147 |url-status=live |journal=Journal of Personality Disorders |volume=25 |issue=2 |pages=136–69 |doi=10.1521/pedi.2011.25.2.136 |pmid=21466247 |archive-url=https://web.archive.org/web/20210829050156/https://www.researchgate.net/publication/51019147_Personality_Disorder_Types_Proposed_for_DSM-5 |archive-date=August 29, 2021 |via=[[ResearchGate]]}}</ref><ref>{{cite journal |last1=Ullrich |first1=Simone |last2=Farrington |first2=David P. |last3=Coid |first3=Jeremy W. |date=December 2007 |title=Dimensions of DSM-IV Personality Disorders and Life-Success |url=https://guilfordjournals.com/doi/10.1521/pedi.2007.21.6.657 |url-status=live |journal=Journal of Personality Disorders |volume=21 |issue=6 |pages=657–663 |doi=10.1521/pedi.2007.21.6.657 |pmid=18072866 |archive-url=https://web.archive.org/web/20220816215848/https://pubmed.ncbi.nlm.nih.gov/18072866/ |archive-date=August 16, 2022 |via=[[Guilford Press]] |s2cid=30040457}}</ref> [[Bullying]] is particularly common towards schizoid individuals.<ref name=":16">{{Cite book |last=Millon |first=Theodore |url=http://archive.org/details/personalitydisor00mill |title=Personality Disorders in Modern Life. [electronic resource] |last2=Millon |first2=Carrie M. |last3=Meagher |first3=Sarah |publisher=Hoboken : John Wiley & Sons |others=Library Genesis |isbn=978-0-471-66850-3 |publication-date=November 8, 2004}}</ref><ref name=":11">Descriptions from [[DSM-III]] (1980) and [[DSM-5]] (2013):"[https://web.archive.org/web/20170202002500/http://displus.sk/DSM/subory/dsm3.pdf#323 Schizoid PD, Associated features (p. 310)]" and [https://books.google.com/books?id=-JivBAAAQBAJ "Schizoid PD (p. 652–655)]".</ref> [[Suicide]] may be a running mental theme for schizoid individuals, though they are not likely to attempt it.<ref name="Klein6">{{cite book |author1=Masterson |first=James |url=https://books.google.com/books?id=PytkjA3HNqQC |title=Disorders of the Self – The Masterson Approach |author2=Klein |first2=Ralph |publisher=[[Taylor & Francis]] |isbn=978-087-630-786-1 |location=New York |publication-date=June 17, 2013 |pages=25–27; pp. 54–55; pp. 95–143 (therapy) |language=en |lccn=95020920 |ol=788549M |author-link=James F. Masterson |archive-url=https://openlibrary.org/works/OL18916879W/Disorders_of_the_self?edition=ia%3Adisordersofselfn0000unse |archive-date=February 18, 2022 |url-status=live}}</ref> Some symptoms of SzPD (e.g. solitary lifestyle, emotional detachment, loneliness, and impaired communication), however, have been stated as general risk factors for serious suicidal behavior.<ref name=":14">{{Cite journal |last1=Levi-Belz |first1=Y. |last2=Gvion |first2=Y. |last3=Levi |first3=U. |last4=Apter |first4=A. |year=2019 |title=Beyond the mental pain: A case-control study on the contribution of schizoid personality disorder symptoms to medically serious suicide attempts |url=https://www.sciencedirect.com/science/article/pii/S0010440X19300136?via%3Dihub |url-status=live |journal=Comprehensive Psychiatry |volume=90 |pages=102–109 |doi=10.1016/j.comppsych.2019.02.005 |pmid=30852349 |archive-url=https://web.archive.org/web/20210606054253/https://www.sciencedirect.com/science/article/pii/S0010440X19300136?via%3Dihub |archive-date=June 6, 2022 |via=[[Elsevier Science Direct]] |doi-access=free}}</ref><ref name="PsychiatriaDanubina">{{cite journal |last1=Attademo |first1=Luigi |last2=Bernardini |first2=Francesco |last3=Spatuzzi |first3=Roberta |date=2021 |title=Suicidality in individuals with schizoid personality disorder or traits: a clinical mini-review of a probably underestimated issue |url=https://www.psychiatria-danubina.com/UserDocsImages/pdf/dnb_vol33_no3/dnb_vol33_no3_261.pdf |url-status=live |journal=Psychiatria Danubina |volume=33 |issue=3 |pages=261–265 |doi=10.24869/psyd.2021.261 |pmid=34795159 |archive-url=https://web.archive.org/web/20220922203658/https://www.psychiatria-danubina.com/UserDocsImages/pdf/dnb_vol33_no3/dnb_vol33_no3_261.pdf |archive-date=September 22, 2022 |s2cid=244385145}}</ref>
<!-- Cause and diagnosis -->
The cause of SzPD is uncertain, but there is some evidence of links and shared genetic risk between SzPD, other [[Personality disorder#Cluster A (odd or eccentric disorders)|cluster A personality disorders]] (such as [[schizotypal personality disorder]]) and [[schizophrenia]]. Thus, SzPD is considered to be a "schizophrenia-like personality disorder".<ref name="ClusterA">{{cite journal|last1=Michelle L. Esterberg|year=2010|title=Cluster A Personality Disorders: Schizotypal, Schizoid and Paranoid Personality Disorders in Childhood and Adolescence|journal=Journal of Psychopathology and Behavioral Assessment|volume=32|issue=4|pages=515–528|doi=10.1007/s10862-010-9183-8|pmc=2992453|pmid=21116455}}</ref><ref name="CharneyNestler2005">[[Dennis S. Charney]], [[Eric J. Nestler]] ''(2005): [https://books.google.com/books?id=en-mwwlzYqgC&pg=PA240 Neurobiology of Mental Illness]''. Oxford Press. {{ISBN|978-0-19-518980-3}}. Schizophrenia-like Personality Disorders. p. 240.</ref> It is diagnosed by clinical observation, and it can be very difficult to distinguish SzPD from other mental disorders or conditions (such as [[autism spectrum]] disorders, with which it may sometimes overlap).<ref name=":17" /><ref name=":21">{{Cite journal|last=Cook|first=Michal L.|year=2019|title=On the Continuity Between Autistic and Schizoid Personality Disorder Trait Burden: A Prospective Study in Adolescence|journal=The Journal of Nervous and Mental Disease|volume=208|issue=2|pages=94–100|doi=10.1097/NMD.0000000000001105|pmid=31856140|pmc=6982569}}</ref>


== History ==
<!-- Prevention and treatment -->
The term "Schizoid" was coined in 1908 by [[Eugen Bleuler]] to describe a human tendency to direct attention toward one's inner life and away from the external world. Bleuler labeled the exaggeration of this tendency the "schizoid personality". He described these personalities as "comfortably dull and at the same time sensitive, people who in a narrow manner pursue vague purposes".<ref name=":132">{{Cite journal |last1=Livesley |first1=W. J. |last2=West |first2=M. |date=February 1986 |title=The DSM-III Distinction between schizoid and avoidant personality disorders |journal=Canadian Journal of Psychiatry |volume=31 |issue=1 |pages=59–62 |doi=10.1177/070674378603100112 |pmid=3948107 |s2cid=46283956}}</ref> In 1910, [[August Hoch]] introduced a very similar concept called the "shut-in" personality. Characteristics of it were reticence, reclusiveness, shyness and a preference for living in fantasy worlds, among others. In 1925, Russian psychiatrist [[Grunya Sukhareva]] described a "schizoid psychopathy" in a group of children, resembling today's SzPD and [[Autism spectrum|ASD]]. About a decade later [[Pyotr Gannushkin]] also included ''Schizoids'' and ''Dreamers'' in his detailed typology of personality types<ref>Both types shared a detachment from the world but ''Schizoids'' also showed eccentricity and paradoxicality of emotional life and behavior, emotional coldness and dryness, unpredictability combined with lack of intuition and ambivalence (e.g., simultaneous presence of both stubbornness and submissiveness). Characteristic of ''Dreamers'' were tenderness and fragility, receptiveness to beauty, weak-willedness and listlessness, luxuriant imagination, [[Glossary of psychiatry#Dereistic thinking|dereism]] and usually an inflated self-concept. ''(From: Gannushkin, P.B (1933). Manifestations of psychopathies: statics, dynamics, systematic aspects.)''</ref>.
The effectiveness of [[psychotherapeutic]] and [[pharmacological]] treatments for SzPD has yet to be empirically and systematically investigated. There is little clinical data on SzPD because it is rarely encountered in clinical settings.<ref name="Medline" /> It is not general practice to treat SzPD with medications, other than for the short-term treatment of associated disorders such as depression or anhedonia.<ref name="mayoclinic" /><ref name="SonnyJoseph" /> Talk therapies such as [[cognitive behavioral therapy]] (CBT) may not be effective, because people with SzPD may have a hard time forming a good working relationship with a therapist.<ref name="Medline" />


The descriptive tradition began in 1925 with the description of observable schizoid behaviors by [[Ernst Kretschmer]]. He organized those into three groups of characteristics:<ref name=":29">{{Cite book |last=Ernst Kretschmer |title=Physique and Character |publisher=Routledge (International Library of Psychology,1999) |year=1931 |isbn=978-0-415-21060-7 |location=London |oclc=858861653}}</ref>
<!-- Epidemiology and prognosis -->
SzPD is a poorly studied disorder. Studies have generally reported a prevalence of less than 1%.<ref name="ClusterA" /><ref name=":10" /><ref name="DSM-5-Schizoid" /> It is more commonly diagnosed in males than in females.<ref name=":10" /> SzPD is linked to negative outcomes, including a significantly compromised [[quality of life]], reduced [[Global Assessment of Functioning|overall functioning]] even after 15 years and one of the lowest levels of "life success" of all personality disorders (measured as "status, wealth and successful relationships").<ref name=":9">Paul Emmelkamp (2013): ''[https://books.google.com/books?id=RwNmAgAAQBAJ Personality Disorders].'' p.54. See [https://www.ncbi.nlm.nih.gov/pubmed/16635645 Cramer (2006)] and [https://www.ncbi.nlm.nih.gov/pubmed/15997609 Hong (2005)] for details.</ref><ref name=":12">{{cite journal |last1=Skodol |first1=Andrew E. |last2=Bender |first2=Donna S. |last3=Morey |first3=Leslie C. |last4=Clark |first4=Lee Anna |last5=Oldham |first5=John M. |last6=Alarcon |first6=Renato D. |last7=Krueger |first7=Robert F. |last8=Verheul |first8=Roel |last9=Bell |first9=Carl C. |last10=Siever |first10=Larry J. |title=Personality Disorder Types Proposed for DSM-5 |journal=Journal of Personality Disorders |date=April 2011 |volume=25 |issue=2 |pages=136–169 |doi=10.1521/pedi.2011.25.2.136 |pmid=21466247 |quote=It [SPD] was found by {{harvnb|Ullrich|Farrington|Coid|2007}} to have the lowest functioning among the PDs with respect to achievement and interpersonal relations...}}
*{{cite journal |first1=Simone |last1=Ullrich |first2=David P. |last2=Farrington |first3=Jeremy W. |last3=Coid |title=Dimensions of DSM-IV Personality Disorders and Life-Success |journal=Journal of Personality Disorders |volume=21|issue=6 |pages=657–663 |date=December 2007 |doi=10.1521/pedi.2007.21.6.657|pmid=18072866 |s2cid=30040457 }}</ref><ref name=":7">{{cite journal |last1=Triebwasser |first1=Joseph |last2=Chemerinski |first2=Eran |last3=Roussos |first3=Panos |last4=Siever |first4=Larry J. |title=Schizoid Personality Disorder |journal=Journal of Personality Disorders |date=December 2012 |volume=26 |issue=6 |pages=919–926 |doi=10.1521/pedi.2012.26.6.919 |pmid=23281676 |s2cid=19412458 |quote=... it seems reasonable for DSM-5 to move away from ScPD as a categorical diagnosis and instead to include Detachment traits as a codable dimension that can have a substantial impact on an individual's functioning and quality of life, and that can moreover be a focus of treatment. }}</ref> [[Bullying]] is particularly common towards schizoid individuals.<ref name="Millon 11" /><ref name=":11" /> [[Suicide]] may be a running mental theme for schizoid individuals, though they are not likely to actually attempt it.<ref name="Klein6" /> Some symptoms of SzPD (e.g. solitary lifestyle, emotional detachment, loneliness and impaired communication), however, have been stated as general risk factors for serious suicidal behaviour.<ref name=":14">{{Cite journal|last1=Levi-Belz|first1=Y.|last2=Gvion|first2=Y.|last3=Levi|first3=U.|last4=Apter|first4=A.|year=2019|title=Beyond the mental pain: A case-control study on the contribution of schizoid personality disorder symptoms to medically serious suicide attempts|journal=Comprehensive Psychiatry|volume=90|pages=102–109|doi=10.1016/j.comppsych.2019.02.005|pmid=30852349|doi-access=free}}</ref><ref name="PsychiatriaDanubina">{{cite journal |last1=Attademo |first1=Luigi |last2=Bernardini |first2=Francesco |last3=Spatuzzi |first3=Roberta |title=Suicidality in individuals with schizoid personality disorder or traits: a clinical mini-review of a probably underestimated issue |journal=Psychiatria Danubina |date=2021 |volume=33 |issue=3 |pages=261–265 |doi=10.24869/psyd.2021.261 |pmid=34795159 |s2cid=244385145 |url=https://www.psychiatria-danubina.com/UserDocsImages/pdf/dnb_vol33_no3/dnb_vol33_no3_261.pdf}}</ref>


# Unsociability, quietness, reservedness, seriousness and eccentricity.
{{TOC limit|3}}
# Timidity, shyness with feelings, sensitivity, nervousness, excitability, fondness of nature and books.
# Pliability, kindliness, honesty, indifference, silence and cold emotional attitudes.<ref name=":29" />


These characteristics were the precursors of the [[DSM-III]] division of the schizoid character into three distinct personality disorders: [[Schizotypal personality disorder|schizotypal]], [[Avoidant personality disorder|avoidant]] and schizoid. Kretschmer himself, however, did not conceive of separating these behaviors to the point of radical isolation but considered them to be simultaneously present as varying potentials in schizoid individuals. For Kretschmer, the majority of schizoids are not ''either'' oversensitive ''or'' cold, but they are oversensitive and cold "at the same time" in quite different relative proportions, with a tendency to move along these dimensions from one behavior to the other.<ref name=":29" />
==Signs and symptoms==
People with SzPD are often aloof, cold and indifferent, which causes interpersonal difficulty. Most individuals diagnosed with SzPD have trouble establishing personal relationships or expressing their feelings meaningfully. They may remain passive in the face of unfavorable situations. Their communication with other people may be indifferent and terse at times. Schizoid personality types often lack the ability to assess the impact of their own actions in social situations.<ref name="Laing1960">{{cite book|title=The Divided Self: an Existential Study in Sanity and Madness|last=Ronald D. Laing|publisher=[[Penguin Books]]|year=1965|isbn=9780140207347|location=Harmondsworth, Middlesex; Baltimore|pages=82–100|chapter=The Inner Self in the Schizoid Condition|oclc=5212085|author-link=R. D. Laing|chapter-url=https://books.google.com/books?id=4JT-12rMtJsC&pg=PT87}}</ref> According to [[Harry Guntrip|Guntrip]], Klein and others, people with SzPD may possess a hidden sense of superiority and lack dependence on other people's opinions.


The second path, that of dynamic psychiatry, began in 1924 with observations by [[Eugen Bleuler]], who observed that the schizoid person and schizoid pathology were not things to be set apart. [[Ronald Fairbairn|Ronald Fairbairn's]] seminal work on the schizoid personality, from which most of what is known today about schizoid phenomena is derived, was presented in 1940. Here, Fairbairn delineated four central schizoid themes:,<ref>Eugen Bleuler – ''Textbook of Psychiatry'', New York: Macmillan (1924)</ref> who observed that the schizoid person and schizoid pathology were not things to be set apart.
[[Aaron Beck]] and his colleagues report that people with SzPD seem comfortable with their aloof lifestyle and consider themselves observers, rather than participants in the world around them. But they also mention that many of their schizoid patients recognize themselves as socially deviant (or even defective) when confronted with the different lives of ordinary people – especially when they read books or see movies focusing on relationships. Even when schizoid individuals may not long for closeness, they can become weary of being "on the outside, looking in". These feelings may lead to depression or [[depersonalization]]. If they do, schizoid people often experience feeling "like a robot" or "going through life in a dream".<ref name="beckfreeman">{{cite book|title=Cognitive Therapy of Personality Disorders|author1=Aaron T. Beck|author1-link=Aaron T. Beck|author2=Arthur Freeman|publisher=The Guilford Press|year=1990|isbn=9780898624342|edition=1st|pages=125 (Millon),127–129 (cognitive therapy conceptualization)|chapter=Chapter 7 Schizoid and Schizotypal PD (p.120-146)|oclc=906420553}}</ref> Although there is the belief that people with SzPD are complacent and unaware of their feelings, many recognize their differences from others. Some individuals in treatment say "life passes them by" or they feel like living inside a shell; they see themselves as "missing the bus" and speak of observing life from a distance.<ref name=":5" /><ref>{{cite book|url=https://books.google.com/books?id=zlFVfzH8orMC&pg=PA236|title=Restructuring Personality Disorders: A Short-Term Dynamic Approach|last=Jeffrey J. Magnavita|publisher=The Guilford Press|year=1997|isbn=978-1-57230-185-6|location=New York|page=237}}</ref>


# The need to regulate interpersonal distance as a central focus of concern.
===Relationships===
# The ability to mobilize [[Self-preservation|self-preservative]] defenses and self-reliance.
People with SzPD tend to be happiest in [[Interpersonal relationship|relationships]] without the expectation of [[Phatic expression|phatic]] or social niceties. It is not necessarily people they want to avoid, but negative ''or'' positive emotional expectations, [[emotional intimacy]] and [[self-disclosure]].<ref name=":0">{{Cite book|title=Split self/split object: understanding and treating borderline, narcissistic, and schizoid disorders.|last=Philip Manfield|publisher=Jason Aronson|year=1992|isbn=978-0-87668-460-3|pages=[https://archive.org/details/splitselfsplitob00manf/page/204 204–207]|url=https://archive.org/details/splitselfsplitob00manf/page/204}}</ref> Therefore, it is possible for individuals with SzPD to form relationships around intellectual, physical, familial, occupational or recreational activities, as long as there is no need for emotional intimacy. [[Donald Winnicott]] explains that this is because schizoid individuals "prefer to make relationships on their own terms and not in terms of the impulses of other people". Failing to attain that, they prefer isolation.<ref>{{Cite book|title=The Family and Individual Development|last=Donald Winnicott|publisher=Routledge|year=2006|isbn=978-0415402774|page=73}}</ref> In general, friendship among schizoids is usually limited to one person, often also schizoid, forming what has been called a union of two eccentrics; "within it – the ecstatic cult of personality, outside it – everything is sharply rejected and despised".<ref>{{Cite book|url=https://books.google.com/books?id=77n_AgAAQBAJ|title=Body structure and character. Studies on the constitution and theory of temperaments|last=[[Ernst Kretschmer]]|date=March 2013|publisher=Ripol Classic|isbn=9785458358392|language=ru|chapter=Chapter 10. Schizoid temperaments|chapter-url=http://sbiblio.com/biblio/archive/krechmer_stroenie/04.aspx}}</ref>
# A pervasive tension between the anxiety-laden need for attachment and the defensive need for distance that manifests in observable behavior as ''indifference''.
# An overvaluation of the inner world at the expense of the outer world.

Following Fairbairn, the dynamic psychiatry tradition has continued to produce rich explorations on the schizoid character, most notably from writers Nannarello (1953), [[R. D. Laing|Laing]] (1965), [[Donald Winnicott|Winnicott]] (1965),<ref>Donald Winnicott (1965): ''[https://books.google.com/books?id=WbGIEhINP6kC The Maturational Processes and the Facilitating Environment: Studies in the Theory of Emotional Development]''. Karnac Books. {{ISBN|9780946439843}}.</ref> [[Harry Guntrip|Guntrip]] (1969), [[Masud Khan|Khan]] (1974), [[Salman Akhtar|Akhtar]] (1987), Seinfeld (1991), Manfield (1992) and Klein (1995).

The [[Diagnostic and Statistical Manual of Mental Disorders|DSM-I]] had the diagnosis of ''Schizoid personality'' which was defined by avoidance of close relationships, inability to express aggressive feelings, and [[Glossary of psychiatry|autistic thinking]].<ref>{{Cite book |url=http://www.turkpsikiyatri.org/arsiv/dsm-1952.pdf |title=Schizoid personality |work=[[Diagnostic and Statistical Manual of Mental Disorders]] |publisher=[[American Psychiatric Association]] |edition=1st |location=[[Washington D.C.]] |page=35 |language=en |archive-url=https://web.archive.org/web/20220814181730/http://www.turkpsikiyatri.org/arsiv/dsm-1952.pdf |archive-date=August 14, 2022 |url-status=live}}</ref> The DSM-II later updated the definition to include [[Daydream|daydreaming]], [[Dissociation (psychology)|detachment from reality]], and sensitivity.<ref>{{Cite book |url=https://www.madinamerica.com/wp-content/uploads/2015/08/DSM-II.pdf |title=Schizoid personality |work=Diagnostic and Statistical Manual of Mental Disorders |publisher=[[American Psychiatric Association]] |year=1968 |edition=2nd |location=[[Washington D.C.]] |page=42 |language=en |archive-url=https://web.archive.org/web/20220425045939/https://www.madinamerica.com/wp-content/uploads/2015/08/DSM-II.pdf |archive-date=April 25, 2022 |url-status=live}}</ref> It was incorporated into the [[Diagnostic and Statistical Manual of Mental Disorders|DSM-III]] as ''Schizoid personality disorder'' to describe difficulties forming meaningful social relationships and a persistent pattern of disconnection and apathy.<ref name=":0">{{Citation |last=Fariba |first=Kamron A. |title=Schizoid Personality Disorder |date=2022 |url=http://www.ncbi.nlm.nih.gov/books/NBK559234/ |work=StatPearls |archive-url=https://web.archive.org/web/20220809053124/https://www.ncbi.nlm.nih.gov/books/NBK559234/ |place=Treasure Island (FL) |publisher=StatPearls Publishing |language=en |pmid=32644660 |access-date=2022-09-24 |archive-date=August 9, 2022 |last2=Madhanagopal |first2=Nandhini |last3=Gupta |first3=Vikas}}</ref><ref>{{Cite book |last=American Psychiatric Association |url=http://archive.org/details/diagnosticstatis00amer_1 |title=Diagnostic and statistical manual of mental disorders : DSM-III-R |last2=American Psychiatric Association. Work Group to Revise DSM-III |date=1987 |publisher=Washington, DC : American Psychiatric Association |others=Internet Archive |isbn=978-0-89042-018-8}}</ref> The diagnosis of SzPD made it to the DSM-IV and DSM-V.<ref>{{Cite book |last=McGraw |first=John G. |url=https://brill.com/view/book/9789401207706/B9789401207706-s016.xml |title=DSM-IV Personality Disorders |date=2012-01-01 |work=Personality Disorders and States of Aloneness |publisher=Brill |isbn=978-94-012-0770-6 |series=Value Inquiry Book Series |volume=246 |language=en |doi=10.1163/9789401207706_016 |archive-url=https://web.archive.org/web/20220622063843/https://brill.com/view/book/9789401207706/B9789401207706-s016.xml |archive-date=June 22, 2022 |url-status=live}}</ref>

== Epidemiology ==
It is also unclear how prevalent the disorder is, although it may be present in anywhere from 0.5% to 7% of the population. Possibly even 14% of the [[Homelessness|homeless]] population.<ref name=":1">{{Cite website |last=Zimmerman |first=Mark |title=Schizoid Personality Disorder (ScPD) - Psychiatric Disorders |url=https://www.msdmanuals.com/en-gb/professional/psychiatric-disorders/personality-disorders/schizoid-personality-disorder-scpd?ruleredirectid=382 |url-status=live |archive-url=https://web.archive.org/web/20220803201543/https://www.msdmanuals.com/en-gb/professional/psychiatric-disorders/personality-disorders/schizoid-personality-disorder-scpd |archive-date=August 3, 2022 |access-date=2022-09-24 |language=en-GB |via=MDS Manual |journal=}}</ref> Gender differences in this disorder are also unclear.<ref name=":0" /><ref>{{Cite journal |last=Grant |first=Bridget F. |last2=Hasin |first2=Deborah S. |last3=Stinson |first3=Frederick S. |last4=Dawson |first4=Deborah A. |last5=Chou |first5=S. Patricia |last6=Ruan |first6=W. June |last7=Pickering |first7=Roger P. |date=2004 |title=Prevalence, correlates, and disability of personality disorders in the United States: results from the national epidemiologic survey on alcohol and related conditions |url=https://pubmed.ncbi.nlm.nih.gov/15291684/ |url-status=live |journal=The Journal of Clinical Psychiatry |volume=65 |issue=7 |pages=948–958 |doi=10.4088/jcp.v65n0711 |issn=0160-6689 |pmid=15291684 |archive-url=https://web.archive.org/web/20220928080329/https://pubmed.ncbi.nlm.nih.gov/15291684/ |archive-date=September 28, 2022 |via=[[PubMed]]}}</ref> Some research has suggested that men may have this disorder more frequently in men than women.<ref name=":2">{{Cite journal |last=Ethesham |first=Hussain |date=April 9, 2009 |title=A study of Hypnotherapy as a special treatment of dissociative, adjustment problems, Personality and Psychosomatic Disorders |url=https://core.ac.uk/download/pdf/11821735.pdf |url-status=live |journal= |publisher=[[Saurashtra University]] |pages=89-90, 133 |archive-url=https://web.archive.org/web/20171110025130/https://core.ac.uk/download/pdf/11821735.pdf |archive-date=November 17, 2022}}</ref><ref>{{Cite journal |last=Fonseca-Pedrero |first=Eduardo |last2=Paino |first2=Mercedes |last3=Santarén-Rosell |first3=Marta |last4=Lemos-Giráldez |first4=Serafín |date=2013 |title=Cluster A maladaptive personality patterns in a non-clinical adolescent population |url=https://pubmed.ncbi.nlm.nih.gov/23628530/ |url-status=live |journal=Psicothema |volume=25 |issue=2 |pages=171–178 |doi=10.7334/psicothema2012.74 |issn=1886-144X |pmid=23628530 |archive-url=https://web.archive.org/web/20210927131056/psicothema.com/pdf/4096.pdf |archive-date=September 27, 2022}}</ref><ref>{{Cite journal |last=Jane |first=J. Serrita |last2=Oltmanns |first2=Thomas F. |last3=South |first3=Susan C. |last4=Turkheimer |first4=Eric |date=2007 |title=Gender bias in diagnostic criteria for personality disorders: an item response theory analysis |url=https://pubmed.ncbi.nlm.nih.gov/17324027/ |url-status=live |journal=Journal of Abnormal Psychology |volume=116 |issue=1 |pages=166–175 |doi=10.1037/0021-843X.116.1.166 |issn=0021-843X |pmc=4372614 |pmid=17324027 |archive-url=https://web.archive.org/web/20220414224448/https://pubmed.ncbi.nlm.nih.gov/17324027/ |archive-date=April 14, 2022}}</ref> SzPD is uncommon in clinical settings (about 2.2%) and occurs more commonly in males. It is rare compared with other personality disorders.<ref name="ClusterA2">{{cite journal |last1=Esterberg |first=Michelle |last2=Goulding |first2=Sandra |last3=Walker |first3=Elaine |year=2010 |title=Cluster A Personality Disorders: Schizotypal, Schizoid and Paranoid Personality Disorders in Childhood and Adolescence |journal=Journal of Psychopathology and Behavioral Assessment |volume=32 |issue=4 |pages=515–528 |doi=10.1007/s10862-010-9183-8 |pmc=2992453 |pmid=21116455 |via=[[PubMed]]}}</ref><ref name=":92">{{Cite book |last=Emmelkamp |first=Paul |url=https://books.google.com/books?id=RwNmAgAAQBAJ |title=Personality Disorders |last2=Kamphuis |first2=Jan |publisher=[[Taylor & Francis]] |isbn=978-131-783-477-9 |publication-date=December 19, 2013 |page=54 |language=en}}</ref><ref name=":102">{{Cite journal |last1=Coid |first1=Jeremy |last2=Yang |first2=Min |last3=Tyrer |first3=Peter |last4=Roberts |first4=Amanda |last5=Ullrich |first5=Simone |date=May 2006 |title=Prevalence and correlates of personality disorder in Great Britain |url=https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/prevalence-and-correlates-of-personality-disorder-in-great-britain/A9F8F2585369857C24C2C46672EECF6E |url-status=live |journal=The British Journal of Psychiatry: The Journal of Mental Science |volume=188 |issue=5 |pages=423–31 |doi=10.1192/bjp.188.5.423 |issn=0007-1250 |pmid=16648528 |archive-url=https://web.archive.org/web/20220314234346/https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/prevalence-and-correlates-of-personality-disorder-in-great-britain/A9F8F2585369857C24C2C46672EECF6E |archive-date=March 14, 2022 |doi-access=free}}</ref> Philip Manfield suggests that the "schizoid condition", which roughly includes the DSM schizoid, avoidant and schizotypal personality disorders, is represented by "as many as forty percent of all personality disorders." Manfield adds "This huge discrepancy [from the ten percent reported by therapists for the condition] is probably largely because someone with a schizoid disorder is less likely to seek treatment than someone with other [[Axis II (psychiatry)|axis-II]] disorders."<ref name=":03">{{Cite book |last=Philip Manfield |url=https://archive.org/details/splitselfsplitob00manf/page/204 |title=Split self/split object: understanding and treating borderline, narcissistic, and schizoid disorders. |publisher=Jason Aronson |year=1992 |isbn=978-0-87668-460-3 |pages=[https://archive.org/details/splitselfsplitob00manf/page/204 204–207] |language=en}}</ref><ref name=":5">{{Cite journal |last=[[George Eman Vaillant]] |year=1985 |title=Maturity of Ego Defenses in Relation to DSM-III Axis II Personality Disorder |url=https://jamanetwork.com/journals/jamapsychiatry/article-abstract/493590 |journal=Archives of General Psychiatry |volume=42 |issue=6 |pages=597–601 |doi=10.1001/archpsyc.1985.01790290079009 |pmid=4004502 |archive-url=https://web.archive.org/web/20201227103531/https://jamanetwork.com/journals/jamapsychiatry/article-abstract/493590 |archive-date=December 27, 2020 |via=[[PubMed]]}}</ref> A 2008 study assessing personality and mood disorder prevalence among [[homeless people]] at New York City [[Drop-in centres|drop-in centers]] reported an SzPD rate of 65% among this sample. The study did not assess homeless people who did not show up at drop-in centers, and the rates of most other personality and mood disorders within the drop-in centers were lower than that of SzPD. The authors noted the limitations of the study, including the higher male-to-female ratio in the sample and the absence of subjects outside the support system or receiving other support (e.g., [[Homeless shelter|shelters]]) as well as the absence of subjects in geographical settings outside New York City, a large city often considered a magnet for disenfranchised people.<ref>{{Cite journal |last=Connolly |first=Adrian J. |year=2008 |title=Personality disorders in homeless drop-in center clients |url=http://www.ncsinc.org/images/pdfs/JPD_article_winter_2008.pdf |url-status=dead |journal=Journal of Personality Disorders |volume=22 |issue=6 |pages=573–588 |doi=10.1521/pedi.2008.22.6.573 |pmid=19072678 |archive-url=https://web.archive.org/web/20090617134208/http://www.ncsinc.org/images/pdfs/JPD_article_winter_2008.pdf |archive-date=2009-06-17}}</ref> A [[University of Colorado Colorado Springs]] study comparing personality disorders and [[Myers–Briggs Type Indicator]] types found that the disorder had a significant correlation with the Introverted (I) and Thinking (T) preferences.<ref>{{cite web |year=2001 |title=An Empirical Investigation of Jung's Personality Types and Psychological Disorder Features |url=http://www.uccs.edu/Documents/dsegal/An-empirical-investigation-Jungs-types-and-PD-features-JPT-2.pdf |url-status=live |archive-url=https://web.archive.org/web/20140125013714/http://www.uccs.edu/Documents/dsegal/An-empirical-investigation-Jungs-types-and-PD-features-JPT-2.pdf |archive-date=2014-01-25 |access-date=August 10, 2013 |publisher=Journal of Psychological Type/[[University of Colorado Colorado Springs]]}}</ref>

== Etiology ==


=== Environmental ===
[[Ronald Fairbairn]] notes that schizoids can fear that in a relationship, their needs will weaken and exhaust their partner, so they feel forced to disown them and move to satisfy solely the needs of the partner. The net result of this is a loss of dignity and sense of self within any relationship they enter, eventually leading to intolerable frustration and friction. Appel notes that these fears result in the schizoid's negativism, stubbornness and reluctance to love. Thus, a central conflict of the schizoid is between an immense longing for relationships but a deep anxiety and avoidance of relationships, manifested by choosing to abandon others as the "lesser evil".<ref name=":03"/>{{rp|100}} A person with SzPD may feel suffocated when their personal space is violated and take actions to avoid this feeling.{{Citation needed|date=July 2021}}
[[Perfectionism (psychology)|Perfectionist]] and hypercritical parenting or cold,<ref>{{Cite journal |last=Jenkins |first=R. L. |last2=Glickman |first2=Sylvia |date=1946 |title=Common syndromes in child psychiatry: II. The schizoid child. |url=http://doi.apa.org/getdoi.cfm?doi=10.1111/j.1939-0025.1946.tb05379.x |url-status=live |journal=American Journal of Orthopsychiatry |language=en |volume=16 |issue=2 |pages=255–261 |doi=10.1111/j.1939-0025.1946.tb05379.x |issn=1939-0025 |archive-url=https://web.archive.org/web/20180603191827/https://psycnet.apa.org/doiLanding?doi=10.1111%2Fj.1939-0025.1946.tb05379.x |archive-date=June 3, 2018}}</ref> neglectful, and distant parenting contribute to the onset of SzPD.<ref name=":1" /><ref name=":2" /><ref>{{Cite journal |last=Bogaerts |first=Stefan |last2=Vanheule |first2=Stijn |last3=Desmet |first3=Mattias |date=2006 |title=Personality Disorders and Romantic Adult Attachment: A Comparison of Secure and Insecure Attached Child Molesters |url=http://journals.sagepub.com/doi/10.1177/0306624X05278515 |journal=International Journal of Offender Therapy and Comparative Criminology |language=en |volume=50 |issue=2 |pages=139–147 |doi=10.1177/0306624X05278515 |issn=0306-624X}}</ref> For a person with SzPD, their parents likely were intolerant of their emotional experiences.<ref>{{Cite journal |last=Lenzenweger |first=Mark F. |date=2010 |title=A source, a cascade, a schizoid: A heuristic proposal from The Longitudinal Study of Personality Disorders |url=https://www.cambridge.org/core/journals/development-and-psychopathology/article/abs/source-a-cascade-a-schizoid-a-heuristic-proposal-from-the-longitudinal-study-of-personality-disorders/3D6448B35E871D142067A99008FE9CA8 |journal=Development and Psychopathology |language=en |volume=22 |issue=4 |pages=867–881 |doi=10.1017/S0954579410000519 |issn=1469-2198}}</ref> They may have been forced to repress and compartmentalize their emotions, possibly resulting in the onset of difficulties expressing and processing emotional experiences.<ref>{{Cite journal |last=Nirestean |first=Aurel |last2=Lukacs |first2=Emese |last3=Cimpan |first3=Dana |last4=Taran |first4=Livia |date=2012 |title=Schizoid personality disorder-the peculiarities of their interpersonal relationships and existential roles: Complex case |url=https://onlinelibrary.wiley.com/doi/10.1002/pmh.1182 |journal=Personality and Mental Health |language=en |volume=6 |issue=1 |pages=69–74 |doi=10.1002/pmh.1182 |via=[[Wiley Online Library]]}}</ref> These difficulties lead to the child feeling rejected and developing the belief that the only safe environment is one where they are alone and inexpressive.<ref>{{Cite journal |last=Ward |first=Shirley |year=2018 |title=The Black Hole: Exploring the Schizoid Personality Disorder, Dysfunction, and Deprivation with their Roots in the Prenatal and Perinatal Period |url=https://www.proquest.com/docview/2183511090?fromopenview=true&pq-origsite=gscholar |url-status=live |journal=Journal of Prenatal & Perinatal Psychology & Health |language=en |volume=33 |issue=1 |access-date=2022-09-29 |via=[[ProQuest]] |website=}}</ref><ref name=":24">{{Cite journal |last=Nirestean |first=Aurel |last2=Lukacs |first2=Emese |last3=Cimpan |first3=Dana |last4=Taran |first4=Livia |date=2012 |title=Schizoid personality disorder-the peculiarities of their interpersonal relationships and existential roles: Complex case |url=https://onlinelibrary.wiley.com/doi/10.1002/pmh.1182 |url-status=live |journal=Personality and Mental Health |language=en |volume=6 |issue=1 |pages=69–74 |doi=10.1002/pmh.1182 |archive-url=https://web.archive.org/web/20150108011737/http://onlinelibrary.wiley.com:80/doi/10.1002/pmh.1182/full |archive-date=January 8, 2015}}</ref><ref>{{Cite journal |last=Simon |first=Andor E. |last2=Keller |first2=Petra |last3=Cattapan |first3=Katja |date=2021-03-01 |title=Commentary about social avoidance and its significance in adolescents and young adults |url=https://www.sciencedirect.com/science/article/pii/S0165178121000159 |journal=Psychiatry Research |language=en |volume=297 |pages=113718 |doi=10.1016/j.psychres.2021.113718 |issn=0165-1781 |via=[[Elsevier Science Direct]]}}</ref><ref name=":18">{{Cite journal |last=Wheeler |first=Zachary |date=2013-01-01 |title=Treatment of schizoid personality: an analytic psychotherapy handbook |url=https://digitalcommons.pepperdine.edu/etd/413 |url-status=live |format=PDF |journal=Theses and Dissertations |archive-url=https://web.archive.org/web/20210404084934/https://digitalcommons.pepperdine.edu/cgi/viewcontent.cgi?article=1412&context=etd |archive-date=April 4, 2021}}</ref> People with SzPD may also have internalized the belief that their emotions are dangerous to themselves and others due to the negative responses received from others.<ref name=":Yontef">{{Cite journal |last=Yontef |first=Gary |date=December 28, 2017 |title=Psychotherapy of Schizoid Process |url=https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.549.1050&rep=rep1&type=pdf |url-status=live |format=PDF |journal=Transactional Analysis Journal |volume=31 |issue=1 |doi=10.1177/036215370103100103 |archive-url=https://web.archive.org/web/20210424011616/https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.549.1050&rep=rep1&type=pdf |archive-date=April 24, 2021 |via=[[CiteSeerX]]}}</ref><ref name=":25">{{Cite journal |last=Waska |first=Robert T. |date=2001-01-01 |title=Schizoid Anxiety: A Reappraisal of the Manic Defense and the Depressive Position |url=https://psychotherapy.psychiatryonline.org/doi/10.1176/appi.psychotherapy.2001.55.1.105 |url-status=live |journal=American Journal of Psychotherapy |volume=55 |issue=1 |pages=105–121 |doi=10.1176/appi.psychotherapy.2001.55.1.105 |issn=0002-9564}}</ref><ref>{{Cite journal |last=Bowins |first=Brad |date=2010 |title=Personality Disorders: A Dimensional Defense Mechanism Approach |url=http://psychotherapy.psychiatryonline.org/doi/10.1176/appi.psychotherapy.2010.64.2.153 |url-status=live |journal=American Journal of Psychotherapy |language=en |volume=64 |issue=2 |pages=153–169 |doi=10.1176/appi.psychotherapy.2010.64.2.153 |issn=0002-9564}}</ref> In their status of isolation and emotional bluntness they can be self-sufficient and safe.<ref>{{Cite journal |last=Kavaler-Adler |first=Susan |date=2004 |title=Anatomy of regret: a developmental view of the depressive position and a critical turn toward love and creativity in the transforming schizoid personality |url=https://pubmed.ncbi.nlm.nih.gov/14993841/ |url-status=live |journal=American Journal of Psychoanalysis |volume=64 |issue=1 |pages=39–76 |doi=10.1023/B:TAJP.0000017991.56175.ea |issn=0002-9548 |pmid=14993841 |via=[[PubMed]]}}</ref><ref>{{Cite book |last=Orcutt |first=Candace |url=https://books.google.com/books?id=jLNaIyVgYzAC&newbks=0&printsec=frontcover&hl=en |title=Trauma in Personality Disorder: A Clinician’S Handbook the Masterson Approach |date=2012-03-31 |publisher=AuthorHouse |isbn=978-1-4685-5814-2 |pages=120-123 |language=en}}</ref> Childhood trauma can also contribute to feelings of emptiness in adulthood.<ref name=":3">{{Cite journal |last=Martens |first=Willem H. J. |date=2010 |title=Schizoid personality disorder linked to unbearable and inescapable loneliness |url=https://scielo.isciii.es/scielo.php?script=sci_abstract&pid=S0213-61632010000100005&lng=es&nrm=iso&tlng=en |url-status=live |journal=The European Journal of Psychiatry |volume=24 |issue=1 |pages=38–45 |issn=0213-6163 |archive-url=https://web.archive.org/web/20160507224616/https://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0213-61632010000100005 |archive-date=May 7, 2016 |via=SciElo}}</ref> [[Alcoholism]] in parents is associated with a heightened risk of developing SzPD.<ref>{{Cite journal |last=Morgan |first=Peter T. |last2=Desai |first2=Rani A. |last3=Potenza |first3=Marc N. |date=2010 |title=Gender-related influences of parental alcoholism on the prevalence of psychiatric illnesses: Analysis of the National Epidemiologic Survey on Alcohol and Related Conditions |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2950877/ |url-status=live |journal=Alcoholism, clinical and experimental research |volume=34 |issue=10 |pages=1759–1767 |doi=10.1111/j.1530-0277.2010.01263.x |issn=0145-6008 |pmc=2950877 |pmid=20645936}}</ref>


===Secret schizoids===
=== Genetic ===
[[Sula Wolff]], who did extensive research and clinical work with children and teenagers with schizoid symptoms, stated that "schizoid personality has a constitutional, probably genetic, basis."<ref>{{Cite book |last=Wolff |first=Sula |url=https://books.google.com/books?id=Oo9kWqaGqkoC&newbks=0&hl=en |title=Loners: The Life Path of Unusual Children |date=1995 |publisher=Psychology Press |isbn=978-0-415-06665-5 |pages=35 |language=en}}</ref> Research on [[heritability]] and this disorder is lacking.<ref name=":0" /> [[Twin studies]] with SzPD traits (e.g. low sociability and low warmth) suggest these are inherited. Besides this indirect evidence, the direct heritability estimates of SzPD range from 50 to 59%.<ref name=":272">{{Cite journal |last=Kendler |first=Kenneth S. |last2=Czajkowski |first2=Nikolai |last3=Tambs |first3=Kristian |last4=Torgersen |first4=Svenn |last5=Aggen |first5=Steven H. |last6=Neale |first6=Michael C. |last7=Reichborn-Kjennerud |first7=Ted |date=2006 |title=Dimensional representations of DSM-IV Cluster A personality disorders in a population-based sample of Norwegian twins: a multivariate study |url=https://www.cambridge.org/core/journals/psychological-medicine/article/abs/dimensional-representations-of-dsmiv-cluster-a-personality-disorders-in-a-populationbased-sample-of-norwegian-twins-a-multivariate-study/7FCB8A9197B4BB25A78ED768491581BB |url-status=live |journal=Psychological Medicine |language=en |volume=36 |issue=11 |pages=1583–1591 |doi=10.1017/S0033291706008609 |issn=1469-8978 |archive-url=https://web.archive.org/web/20220301170757/https://www.cambridge.org/core/journals/psychological-medicine/article/abs/dimensional-representations-of-dsmiv-cluster-a-personality-disorders-in-a-populationbased-sample-of-norwegian-twins-a-multivariate-study/7FCB8A9197B4BB25A78ED768491581BB |archive-date=March 1, 2022 |via=[[Cambridge Core]]}}</ref><ref>{{Cite book |last=Ph.D |first=Paul H. Blaney |url=https://books.google.com/books?id=NQ0bBAAAQBAJ&newbks=0&printsec=frontcover&pg=PA639&hl=en |title=Oxford Textbook of Psychopathology |last2=Ph.D |first2=Robert F. Krueger |last3=Ph.D |first3=Theodore Millon |date=2014-08-22 |publisher=Oxford University Press |isbn=978-0-19-981184-7 |pages=649 |language=en}}</ref> Other research has found the heritability rate to be 29%.<ref>{{Cite journal |last=Reichborn-Kjennerud |first=Ted |date=2010 |title=The genetic epidemiology of personality disorders |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3181941/ |url-status=live |journal=Dialogues in Clinical Neuroscience |volume=12 |issue=1 |pages=103–114 |issn=1294-8322 |pmc=3181941 |pmid=20373672 |archive-url=https://web.archive.org/web/20220521172211/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3181941/ |archive-date=May 21, 2022}}</ref> Researchers are also unsure of the [[pathophysiology]] of SzPD. [[Genetic distance|Genetic relationships]] with people who have [[Schizophrenia spectrum disorders]] increase the risk of developing Schizoid Personality Disorder.<ref>{{Cite journal |last=Yang |first=Tien-Wei |last2=Chen |first2=Wei |last3=Liu |first3=Shi |last4=Cheng |first4=Joseph |last5=Ou-Yang |first5=Wen-Chen |last6=Chang |first6=Hung-Jung |last7=Lane |first7=Hsien-Yuan |last8=Chang |first8=Ching-Jui |last9=Lin |first9=Shi-Kwang |last10=Hwu |first10=Hai-Gwo |date=January 1, 2002 |title=Morbidity Risk of Psychiatric Disorders Among the First Degree Relatives of Schizophrenia Patients in Taiwan |url=https://academic.oup.com/schizophreniabulletin/article/28/3/379/1839369?login=false |url-status=live |journal=[[Schizophrenia Bulletin]] |language=En |volume=28 |issue=3 |doi=10.1093/oxfordjournals.schbul.a006947 |archive-url=https://web.archive.org/web/20180729225136/https://watermark.silverchair.com/28-3-379.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAdYwggHSBgkqhkiG9w0BBwagggHDMIIBvwIBADCCAbgGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMjudcgw3CrZ9Z69SzAgEQgIIBiXPuc4EGIkmLBjTKaAow6MypqylCKH29ecpHZkUgrkBeq3jaqixW_CWr8qsx7eYsxZJGAEm2zga042azIu4LwT4uH-rltbpYaMybmuipNJgbWQ7tQe6RqZ_r4xLesm2zToJ0-R3VvQbAmXpLdapDHfySj_9X7D29IHZecnKcVkNYpQ4Em5I9EhQCcpcfaqVSw0HaeWVyaW8v19HfrLyDHKsGmCQ2_Pms5mDbnCMSarqH2odxnLHdDyvoZyUB2x00Ns00M1PuhNH_JTCEMXzsLTTDtH7_JY2kYzAa-AxQQ08Vgyc9t9GNCRMrzdnwMXV0u7eUCqKAajvgyBRqe-_iKbeL6ln3vDfJhsLSqPlAUScK8KtInYRlDe09nmdnqNPArelifXZP7GauYHayWqQM9EmESqrXofZDD704iJvD2AgMClksp6TOngyumLTPI0AhJXDV8ujHENKgxWYwJT0F_xsMo-gBp-TYWohE5pgtZCaiJGUBrkwJ6B3ni27glpGG-VztX6vSNJdtYA |archive-date=July 29, 2018 |access-date=2022-09-25 |via=[[Oxford Academic]]}}</ref><ref>{{Cite journal |last=Racioppi |first=Anna |last2=Sheinbaum |first2=Tamara |last3=Gross |first3=Georgina M. |last4=Ballespí |first4=Sergi |last5=Kwapil |first5=Thomas R. |last6=Barrantes-Vidal |first6=Neus |date=2018-11-08 |title=Prediction of prodromal symptoms and schizophrenia-spectrum personality disorder traits by positive and negative schizotypy: A 3-year prospective study |url=https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0207150 |url-status=live |journal=PLOS ONE |language=en |volume=13 |issue=11 |pages=e0207150 |doi=10.1371/journal.pone.0207150 |issn=1932-6203 |pmc=PMC6224105 |pmid=30408119 |archive-url=https://web.archive.org/web/20220621065654/https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0207150 |archive-date=June 21, 2022}}</ref><ref>{{Cite journal |last=Fogelson |first=David L. |last2=Nuechterlein |first2=Keith H. |last3=Asarnow |first3=Robert F. |last4=Payne |first4=Diana L. |last5=Subotnik |first5=Kenneth L. |date=2004-06-01 |title=Validity of the family history method for diagnosing schizophrenia, schizophrenia-related psychoses, and schizophrenia-spectrum personality disorders in first-degree relatives of schizophrenia probands |url=https://www.sciencedirect.com/science/article/pii/S0920996403000811 |url-status=live |journal=Schizophrenia Research |language=en |volume=68 |issue=2 |pages=309–317 |doi=10.1016/S0920-9964(03)00081-1 |issn=0920-9964 |archive-url=https://web.archive.org/web/20220620024154/https://www.sciencedirect.com/science/article/abs/pii/S0920996403000811 |archive-date=June 20, 2022 |via=[[Elsevier Science Direct]]}}</ref><ref>{{Cite journal |last=Ahmed |first=Anthony Olufemi |last2=Green |first2=Bradley Andrew |last3=Buckley |first3=Peter Francis |last4=McFarland |first4=Megan Elizabeth |date=2012-03-30 |title=Taxometric analyses of paranoid and schizoid personality disorders |url=https://www.sciencedirect.com/science/article/pii/S0165178111006925 |journal=Psychiatry Research |language=en |volume=196 |issue=1 |pages=123–132 |doi=10.1016/j.psychres.2011.10.010 |issn=0165-1781}}</ref> People with SzPD can have a history of [[schizotypy]] before developing the disorder.<ref>{{Cite journal |last=Kotlicka-Antczak |first=Magdalena |last2=Karbownik |first2=Michał S. |last3=Pawełczyk |first3=Agnieszka |last4=Żurner |first4=Natalia |last5=Pawełczyk |first5=Tomasz |last6=Strzelecki |first6=Dominik |last7=Urban-Kowalczyk |first7=Małgorzata |date=2019-04-01 |title=A developmentally-stable pattern of premorbid schizoid-schizotypal features predicts psychotic transition from the clinical high-risk for psychosis state |url=https://www.sciencedirect.com/science/article/pii/S0010440X19300112 |url-status=live |journal=Comprehensive Psychiatry |language=en |volume=90 |pages=95–101 |doi=10.1016/j.comppsych.2019.02.003 |issn=0010-440X |archive-url=https://web.archive.org/web/20220502032220/https://www.sciencedirect.com/science/article/pii/S0010440X19300112 |archive-date=May 2, 2022 |via=[[Elsevier Science Direct]]}}</ref><ref>{{Cite journal |last=Fogelson |first=D. L. |last2=Nuechterlein |first2=K. H. |last3=Asarnow |first3=R. A. |last4=Payne |first4=D. L. |last5=Subotnik |first5=K. L. |last6=Jacobson |first6=K. C. |last7=Neale |first7=M. C. |last8=Kendler |first8=K. S. |date=2007 |title=Avoidant Personality Disorder is a Separable Schizophrenia Spectrum Personality Disorder even when Controlling for the Presence of Paranoid and Schizotypal Personality Disorders |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1904485/ |journal=Schizophrenia research |volume=91 |issue=1-3 |pages=192–199 |doi=10.1016/j.schres.2006.12.023 |issn=0920-9964 |pmc=1904485 |pmid=17306508 |archive-url=https://web.archive.org/web/20210829050420/https://www.sciencedirect.com/science/article/abs/pii/S092099640700031X?dgcid=api_sd_search-api-endpoint |archive-date=August 29, 2021}}</ref><ref>{{Cite journal |last=Ford |first=Talitha C. |last2=Crewther |first2=David P. |date=2014 |title=Factor Analysis Demonstrates a Common Schizoidal Phenotype within Autistic and Schizotypal Tendency: Implications for Neuroscientific Studies |url=https://www.frontiersin.org/articles/10.3389/fpsyt.2014.00117 |url-status=live |journal=Frontiers in Psychiatry |volume=5 |doi=10.3389/fpsyt.2014.00117/full |issn=1664-0640 |archive-url=https://web.archive.org/web/20220709124029/https://www.frontiersin.org/articles/10.3389/fpsyt.2014.00117/full |archive-date=July 9, 2022}}</ref><ref>{{Cite journal |last=Via |first=Esther |last2=Orfila |first2=Carles |last3=Pedreño |first3=Carla |last4=Rovira |first4=Antoni |last5=Menchón |first5=José M. |last6=Cardoner |first6=Narcís |last7=Palao |first7=Diego J. |last8=Soriano-Mas |first8=Carles |last9=Obiols |first9=Jordi E. |date=2016-12-01 |title=Structural alterations of the pyramidal pathway in schizoid and schizotypal cluster A personality disorders |url=https://www.sciencedirect.com/science/article/pii/S0167876016306808 |journal=International Journal of Psychophysiology |language=en |volume=110 |pages=163–170 |doi=10.1016/j.ijpsycho.2016.08.006 |issn=0167-8760}}</ref> SzPD symptoms can be [[Premorbidity|premorbid]] to Schizophrenia.<ref>{{Cite journal |last=Herrera Rodríguez |first=Alba |date=2013 |title=Schizophrenia at adolescence: the relationship between schizophrenia self-reported symptoms and substance abuse, schizoid personality disorder symptoms and migration history |url=https://dugi-doc.udg.edu/handle/10256/10537 |url-status=live |journal= |archive-url=https://web.archive.org/web/20220925191006/https://dugi-doc.udg.edu/handle/10256/10537?show=full |archive-date=September 25, 2022}}</ref><ref>{{Cite journal |last=Díaz-Castro |first=Lina |last2=Hoffman |first2=Kurt |last3=Cabello-Rangel |first3=Héctor |last4=Arredondo |first4=Armando |last5=Herrera-Estrella |first5=Miguel Ángel |date=2021 |title=Family History of Psychiatric Disorders and Clinical Factors Associated With a Schizophrenia Diagnosis |url=http://journals.sagepub.com/doi/10.1177/00469580211060797 |url-status=live |journal=INQUIRY: The Journal of Health Care Organization, Provision, and Financing |language=en |volume=58 |pages=004695802110607 |doi=10.1177/00469580211060797 |issn=0046-9580 |pmc=PMC8673879 |pmid=34845937 |archive-url=https://web.archive.org/web/20220927153558/https://pubmed.ncbi.nlm.nih.gov/34845937/ |archive-date=September 27, 2022}}</ref><ref>{{Cite journal |last=Boldrini |first=Tommaso |last2=Tanzilli |first2=Annalisa |last3=Di Cicilia |first3=Giuseppe |last4=Gualco |first4=Ivan |last5=Lingiardi |first5=Vittorio |last6=Salcuni |first6=Silvia |last7=Tata |first7=Maria Cristina |last8=Vicari |first8=Stefano |last9=Pontillo |first9=Maria |date=2020 |title=Personality Traits and Disorders in Adolescents at Clinical High Risk for Psychosis: Toward a Clinically Meaningful Diagnosis |url=https://www.frontiersin.org/articles/10.3389/fpsyt.2020.562835 |url-status=live |journal=Frontiers in Psychiatry |volume=11 |doi=10.3389/fpsyt.2020.562835/full |issn=1664-0640 |archive-url=https://web.archive.org/web/20220818062450/https://www.frontiersin.org/articles/10.3389/fpsyt.2020.562835/full |archive-date=August 18, 2022}}</ref><ref>{{Cite journal |last=Chen |first=C.-K. |last2=Lin |first2=S.-K. |last3=Sham |first3=P. 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M. |date=2003 |title=Pre-morbid characteristics and co-morbidity of methamphetamine users with and without psychosis |url=https://www.cambridge.org/core/journals/psychological-medicine/article/abs/premorbid-characteristics-and-comorbidity-of-methamphetamine-users-with-and-without-psychosis/867A38591939F3A64E9A1821BF075A76 |url-status=live |journal=Psychological Medicine |language=en |volume=33 |issue=8 |pages=1407–1414 |doi=10.1017/S0033291703008353 |issn=1469-8978 |archive-url=https://web.archive.org/web/20220425153634/https://www.cambridge.org/core/journals/psychological-medicine/article/abs/premorbid-characteristics-and-comorbidity-of-methamphetamine-users-with-and-without-psychosis/867A38591939F3A64E9A1821BF075A76 |archive-date=April 25, 2022}}</ref><ref>{{Cite journal |last=Green |first=Michael F. |last2=Horan |first2=William P. |last3=Lee |first3=Junghee |last4=McCleery |first4=Amanda |last5=Reddy |first5=L. Felice |last6=Wynn |first6=Jonathan K. |date=2018-02-15 |title=Social Disconnection in Schizophrenia and the General Community |url=https://pubmed.ncbi.nlm.nih.gov/28637195/ |url-status=live |journal=Schizophrenia Bulletin |volume=44 |issue=2 |pages=242–249 |doi=10.1093/schbul/sbx082 |issn=1745-1701 |pmc=5814840 |pmid=28637195 |archive-url=https://web.archive.org/web/20210826091415/https://pubmed.ncbi.nlm.nih.gov/28637195/ |archive-date=September 29, 2021}}</ref><ref>{{Cite journal |last=Bolinskey |first=P. Kevin |last2=Smith |first2=Elizabeth A. |last3=Schuder |first3=Kelly M. |last4=Cooper-Bolinskey |first4=Dianna |last5=Myers |first5=Kevin R. |last6=Hudak |first6=Daniel V. |last7=James |first7=Alison V. |last8=Hunter |first8=Helen K. |last9=Novi |first9=Jonathan H. |last10=Guidi |first10=Janice P. |last11=Gonzalez |first11=Yelena |last12=McTiernan |first12=Erin F. |last13=Arnold |first13=Kaitlin M. |last14=Iati |first14=Carina A. |last15=Gottesman |first15=Irving I. |date=2017-06-01 |title=Schizophrenia spectrum personality disorders in psychometrically identified schizotypes at two-year follow-up |url=https://www.sciencedirect.com/science/article/pii/S0165178116314780 |url-status=live |journal=Psychiatry Research |language=en |volume=252 |pages=289–295 |doi=10.1016/j.psychres.2017.03.014 |issn=0165-1781}}</ref>
Many schizoid individuals display an engaging, interactive personality, contradicting the observable characteristic emphasized by the [[DSM-5]] and [[ICD-10]] definitions of the schizoid personality. Guntrip (using ideas of Klein, Fairbairn and Winnicott) classifies these individuals as "secret schizoids", who behave with socially available, interested, engaged and involved interaction yet remain emotionally withdrawn and sequestered within the safety of the internal world.<ref name="Klein6">{{cite book|url=https://books.google.com/books?id=PytkjA3HNqQC|title=Disorders of the Self – The Masterson Approach|author1=James F. Masterson|author2=Ralph Klein|publisher=Brunner / Mazel|year=1995|isbn=9780876307861|location=New York|pages=25–27; pp. 54–55; pp. 95–143 (therapy)|author-link=James F. Masterson}}</ref>{{rp|17}}<ref name="Falk2008">{{cite book|author=Avner Falk|title=Islamic Terror: Conscious and Unconscious Motives|url=https://books.google.com/books?id=tcTpj4MMqxIC&pg=PA98|year=2008|publisher=ABC-CLIO|isbn=978-0-313-35764-0|pages=98}}</ref> Klein distinguishes between a "classic" SzPD and a "secret" SzPD, which occur "just as often" as each other. Klein cautions one should not misidentify the schizoid person as a result of the patient's defensive, compensatory interaction with the external world. He suggests one ask the person what their subjective experience is, to detect the presence of the schizoid refusal of emotional intimacy and preference for objective fact.<ref name="Klein6" />


=== Neurological ===
Frequently, a schizoid individual's social functioning improves, sometimes dramatically, when the individual knows they are an anonymous participant in a real-time conversation or correspondence, e.g. in an online chatroom or message board. It is often the case the individual's online correspondent will report nothing amiss in the individual's engagement and affect.{{Citation needed|date=August 2019|reason=Couldn't find a source for this. However, one source stated that schizoids spend the most time online out of any personality disorder.}} A 2013 study looking at personality disorders and Internet use found that being online more hours per day predicted signs of SzPD. Additionally, SzPD correlated with lower phone call use and fewer Facebook friends.<ref>{{Cite journal|last1=Rosen|first1=L. D.|last2=Whaling|first2=K.|last3=Rab|first3=S.|last4=Carrier|first4=L. M.|last5=Cheever|first5=N. A.|year=2013|title=Is Facebook creating 'iDisorders'? The link between clinical symptoms of psychiatric disorders and technology use, attitudes and anxiety|journal=Computers in Human Behavior|volume=29|issue=3|pages=1243–1254|doi=10.1016/j.chb.2012.11.012 }}</ref>
[[Prenatal nutrition|Prenatal malnutrition]],<ref>{{Cite journal |last=Lumey |first=L.H. |last2=Stein |first2=Aryeh D. |last3=Susser |first3=Ezra |date=2011 |title=Prenatal Famine and Adult Health |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3857581/ |journal=Annual review of public health |volume=32 |pages=10.1146/annurev–publhealth–031210-101230 |doi=10.1146/annurev-publhealth-031210-101230 |issn=0163-7525 |pmc=3857581 |pmid=21219171}}</ref><ref>{{Cite journal |last=de Rooij |first=Susanne R. |last2=Wouters |first2=Hans |last3=Yonker |first3=Julie E. |last4=Painter |first4=Rebecca C. |last5=Roseboom |first5=Tessa J. |date=2010 |title=Prenatal undernutrition and cognitive function in late adulthood |url=https://www.jstor.org/stable/20779880 |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=107 |issue=39 |pages=16881–16886 |issn=0027-8424}}</ref> [[Preterm birth|premature birth]], and low [[birth weight]] are all thought to play a role in the development of SzPD.<ref name=":162">{{Cite book |last=Millon |first=Theodore |url=http://archive.org/details/personalitydisor00mill |title=Personality Disorders in Modern Life. [electronic resource] |last2=Millon |first2=Carrie M. |last3=Meagher |first3=Sarah |publisher=Hoboken : John Wiley & Sons |others=Library Genesis |isbn=978-0-471-66850-3 |publication-date=November 8, 2004}}</ref><ref>{{Cite journal |last=Abel |first=Kathryn |last2=Wicks |first2=Susanne |last3=Susser |first3=Ezra |year=2010 |title=Birth Weight, Schizophrenia, and Adult Mental Disorder Is Risk Confined to the Smallest Babies? |url=https://jamanetwork.com/journals/jamapsychiatry/fullarticle/210877 |url-status=live |journal=Arch Gen Psychiatry |doi=10.1001/archgenpsychiatry.2010.100 |access-date=2022-10-02 |via=[[JAMA Network]]}}</ref><ref name=":4">{{Cite journal |last=Li |first=Tianxin |date=2021-12-24 |title=An Overview of Schizoid Personality Disorder |url=https://www.atlantis-press.com/proceedings/ichess-21/125967236 |url-status=live |journal= |language=en |publisher=Atlantis Press |pages=1657–1663 |doi=10.2991/assehr.k.211220.280 |isbn=978-94-6239-495-7 |archive-url=https://web.archive.org/web/20220427112740/https://www.atlantis-press.com/proceedings/ichess-21/125967236 |archive-date=April 27, 2022}}</ref><ref>{{Cite journal |last=Mather |first=Amber A. |last2=Cox |first2=Brian J. |last3=Enns |first3=Murray W. |last4=Sareen |first4=Jitender |date=2008 |title=Associations Between Body Weight and Personality Disorders in a Nationally Representative Sample |url=https://journals.lww.com/psychosomaticmedicine/Abstract/2008/11000/Associations_Between_Body_Weight_and_Personality.8.aspx |journal=Psychosomatic Medicine |language=en-US |volume=70 |issue=9 |pages=1012–1019 |doi=10.1097/PSY.0b013e318189a930 |issn=0033-3174}}</ref> SzPD is associated with reduced [[serotonergic]] and [[Dopaminergic pathways|dopaminergic]] pathways in areas such as the [[frontal lobe]], [[amygdala]], and [[striatum]].<ref>{{Cite journal |last=Laakso |first=Aki |last2=Vilkman |first2=Harry |last3=Kajander |first3=Jaana |last4=Bergman |first4=Jörgen |last5=Haaparanta |first5=Merja |last6=Solin |first6=Olof |last7=Hietala |first7=Jarmo |date=2000-02-01 |title=Prediction of Detached Personality in Healthy Subjects by Low Dopamine Transporter Binding |url=https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.157.2.290 |journal=American Journal of Psychiatry |volume=157 |issue=2 |pages=290–292 |doi=10.1176/appi.ajp.157.2.290 |issn=0002-953X}}</ref><ref name=":22">{{Cite journal |last=Hemmati |first=Azad |last2=Rezaei |first2=Farzin |last3=Rahmani |first3=Khaled |last4=Shams-Alizadeh |first4=Narges |last5=Davarinejad |first5=Omran |last6=Shirzadi |first6=Maryam |last7=Komasi |first7=Saeid |date=2022-01-01 |title=Differential profile of three overlap psychiatric diagnoses using temperament and character model: A systematic review and meta-analysis of avoidant personality disorder, schizoid personality disorder, and social anxiety disorder |url=https://www.anip.co.in/article.asp?issn=2588-8358;year=2022;volume=6;issue=1;spage=15;epage=26;aulast=Hemmati;type=0 |url-status=live |journal=Annals of Indian Psychiatry |language=en |volume=6 |issue=1 |pages=15 |doi=10.4103/aip.aip_148_21 |issn=2588-8358 |archive-url=https://web.archive.org/web/20220926210907/https://www.anip.co.in/article.asp?issn=2588-8358;year=2022;volume=6;issue=1;spage=15;epage=26;aulast=Hemmati;type=0 |archive-date=September 26, 2022}}</ref><ref>{{Cite journal |last=Dolan |first=M. |last2=Anderson |first2=I. M. |last3=Deakin |first3=J. F. W. |date=2001 |title=Relationship between 5-HT function and impulsivity and aggression in male offenders with personality disorders |url=https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/relationship-between-5ht-function-and-impulsivity-and-aggression-in-male-offenders-with-personality-disorders/BA7A31EEDC424B3E58BB185918669956 |journal=The British Journal of Psychiatry |language=en |volume=178 |issue=4 |pages=352–359 |doi=10.1192/bjp.178.4.352 |issn=0007-1250}}</ref><ref>{{Cite journal |last=Zald |first=David H. |last2=Treadway |first2=Michael |date=2017-05-08 |title=Reward Processing, Neuroeconomics, and Psychopathology |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5958615/ |url-status=live |journal=Annual review of clinical psychology |volume=13 |pages=471–495 |doi=10.1146/annurev-clinpsy-032816-044957 |issn=1548-5943 |pmc=5958615 |pmid=28301764 |archive-url=https://web.archive.org/web/20220821033255/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5958615/ |archive-date=August 21, 2022}}</ref> [[Traumatic brain injury|Traumatic brain injuries]] to the frontal lobe may also contribute to the onset of SzPD as that area of the brain controls areas such as emotion and socialization.<ref>{{Cite web |last=Hadfield |first=Media Contact: Joe |date=2014-04-09 |title=Head injuries can make children loners |url=https://news.byu.edu/news/head-injuries-can-make-children-loners |access-date=2022-10-02 |website=News |language=en}}</ref><ref name=":3" /><ref>{{Cite journal |last=Blanchard |first=Jack J. |last2=Aghevli |first2=Minu |last3=Wilson |first3=Amy |last4=Sargeant |first4=Marsha |date=2010-05-01 |title=Developmental instability in social anhedonia: An examination of minor physical anomalies and clinical characteristics |url=https://www.sciencedirect.com/science/article/pii/S0920996409005519 |url-status=live |journal=Schizophrenia Research |language=en |volume=118 |issue=1 |pages=162–167 |doi=10.1016/j.schres.2009.10.028 |issn=0920-9964 |archive-url=https://web.archive.org/web/20200209075626/https://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC2856752&blobtype=pdf |archive-date=February 9, 2022}}</ref> Deficits in the right hemisphere of the brain may also be associated with SzPD.<ref>{{Cite journal |last=Wolff |first=Sula |date=1991 |title=‘Schizoid’ Personality in Childhood and Adult Life I: The Vagaries of Diagnostic Labelling |url=https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/abs/schizoid-personality-in-childhood-and-adult-life-i-the-vagaries-of-diagnostic-labelling/AD2266DB81659F02DDE029A9B304D332 |journal=The British Journal of Psychiatry |language=en |volume=159 |issue=5 |pages=615–620 |doi=10.1192/bjp.159.5.615 |issn=0007-1250}}</ref> Lower levels of [[Low-density lipoprotein|low-density lipoprotein cholesterol]] may be correlated with the presence of Schizoid traits in women.<ref>{{Cite journal |last=Hayakawa |first=Kohei |last2=Watabe |first2=Motoki |last3=Horikawa |first3=Hideki |last4=Sato-Kasai |first4=Mina |last5=Shimokawa |first5=Norihiro |last6=Nakao |first6=Tomohiro |last7=Kato |first7=Takahiro A. |date=2022 |title=Low-Density Lipoprotein Cholesterol Is a Possible Blood Biomarker of Schizoid Personality Traits among Females |url=https://www.mdpi.com/2075-4426/12/2/131 |url-status=live |journal=Journal of Personalized Medicine |language=en |volume=12 |issue=2 |pages=131 |doi=10.3390/jpm12020131 |issn=2075-4426 |archive-url=https://web.archive.org/web/20220619085042/https://www.mdpi.com/2075-4426/12/2/131 |archive-date=June 19, 2022}}</ref> Excess indices in the left hemisphere may also be related to SzPD.<ref>{{Cite journal |last=I.v |first=Pluzhnikov |last2=V.g |first2=Kaleda |date=2015-06-01 |title=Neuropsychological findings in personality disorders: A.R. Luria’s Approach. |url=http://psychologyinrussia.com/volumes/pdf/2015_2/2015_2_113-125.pdf |journal=Psychology in Russia: State of Art |language=en |volume=8 |issue=2 |pages=113–125 |doi=10.11621/pir.2015.0210 |issn=2074-6857}}</ref>


== Prognosis ==
Descriptions of the schizoid personality as "hidden" behind an outward appearance of emotional engagement have been recognized since 1940, with Fairbairn's description of "schizoid exhibitionism", in which the schizoid individual is able to express a great deal of feeling and to make what appear to be impressive social contacts yet in reality gives nothing and loses nothing. Because they are "playing a part", their personality is not involved. According to Fairbairn, ''the person'' disowns the part they are playing, and the schizoid individual seeks to preserve their personality intact and immune from compromise.<ref>{{cite book |author=W. R. D. Fairbairn |author-link=Ronald Fairbairn |title=Psychoanalytic Studies of the Personality |url=https://books.google.com/books?id=LwxoUHnyvj0C |date=2013 |publisher=Routledge |isbn=978-1-134-84213-1 |pages=3–17}}</ref> The schizoid's false persona is based around what those around them define as normal or good behaviour, as a form of compliance.<ref name=":03" />{{rp|143}} Further references to the secret schizoid come from [[Masud Khan]],<ref name=":1">{{Cite book|title=The Privacy of the Self – Papers on Psychoanalytic Theory and Technique|author=Masud Khan|author-link=Masud Khan|publisher=International Universities Press|year=1974|isbn=978-0823643103|location=New York|page=70|chapter=The Role of phobic and counter-phobic mechanisms and separation anxiety in schizoid character formation}}</ref> Jeffrey Seinfeld<ref name=":2">{{cite book |author=Jeffrey Seinfeld|title=The Empty Core: An Object Relations Approach to Psychotherapy of the Schizoid Personality |url=https://books.google.com/books?id=r9ZrAAAAMAAJ |year=1991 |publisher=J. Aronson |isbn=978-0-87668-611-9 |quote=Seinfeld writes: "The schizoid may also seem to be sociable and involved in relationships. However, he is frequently playing a role and not 'fully' involved, unconsciously disowning this role..."}}</ref> and Philip Manfield,<ref name=":0" /> who give a description of an SzPD individual who "enjoys" public speaking engagements but experiences great difficulty in the breaks when audience members would attempt to engage him emotionally. These references expose the problems in relying on outer observable behavior for assessing the presence of personality disorders in certain individuals.
Traits of Schizoid Personality Disorder appear in [[Child|childhood]] and [[adolescence]]. Children with this disorder usually have poor relationships with others,<ref>{{Cite book |last=Dobbert |first=Duane L. |url=https://books.google.com/books?id=rpFxDwAAQBAJ&newbks=0&hl=en |title=Understanding Personality Disorders: An Introduction: An Introduction |date=2007-01-30 |publisher=ABC-CLIO |isbn=978-0-313-06804-1 |pages=17-21 |language=en}}</ref><ref>{{Cite journal |last=Tackett |first=Jennifer |last2=Balsis |first2=Steve |last3=Oltmanns |first3=Thomas F. |last4=Krueger |first4=Robert |date=2009 |title=A unifying perspective on personality pathology across the life span: Developmental considerations for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2864523/ |url-status=live |journal=Development and psychopathology |volume=21 |issue=3 |pages=687–713 |doi=10.1017/S095457940900039X |issn=0954-5794 |pmc=2864523 |pmid=19583880 |archive-url=https://web.archive.org/web/20220519102857/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2864523/ |archive-date=May 19, 2022}}</ref> [[social anxiety]], internal fantasies, strange behavior, and hyperactivity. These behaviors usually result in teasing and [[bullying]] at the hands of others.<ref>{{Cite journal |last=Kagan |first=Dana |date=2004-05-04 |title=Positive reinforcement as an intervention for children with attention deficit hyperactivity disorder and schizoid personality disorder |url=https://rdw.rowan.edu/etd/1171 |url-status=live |journal=Theses and Dissertations |archive-url=https://web.archive.org/web/20220925221126/https://rdw.rowan.edu/etd/1171/ |archive-date=September 25, 2022}}</ref><ref>{{Cite journal |last=Weiss |first=Elisabeth M. |last2=Schulter |first2=Günter |last3=Freudenthaler |first3=H. Harald |last4=Hofer |first4=Ellen |last5=Pichler |first5=Natascha |last6=Papousek |first6=Ilona |date=2012-05-31 |title=Potential Markers of Aggressive Behavior: The Fear of Other Persons' Laughter and Its Overlaps with Mental Disorders |url=https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0038088 |url-status=live |journal=PLOS ONE |language=en |volume=7 |issue=5 |pages=e38088 |doi=10.1371/journal.pone.0038088 |issn=1932-6203 |pmc=PMC3364988 |pmid=22675438 |archive-url=https://web.archive.org/web/20220420001337/https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0038088 |archive-date=April 20, 2022}}</ref> It is common for people with SzPD to have had [[Major depressive disorder|Major Depressive Disorder]] in childhood.<ref name=":102" /><ref>{{Cite journal |last=Ramklint |first=Mia |last2=Ramklint |first2=Mia |last3=Ramklint |first3=Mia |date=2003-01-01 |title=Child and adolescent psychiatric disorders predicting adult personality disorder: A follow-up study |url=https://doi.org/10.1080/psc.57.1.23 |journal=Nordic Journal of Psychiatry |volume=57 |issue=1 |pages=23–28 |doi=10.1080/psc.57.1.23 |issn=0803-9488}}</ref> SzPD is associated with lower levels of achievement and a compromised [[quality of life]].<ref name=":102" /><ref>{{Cite journal |last=Sevilla‐Llewellyn‐Jones |first=Julia |last2=Cano‐Domínguez |first2=Pablo |last3=de‐Luis‐Matilla |first3=Antonia |last4=Espina‐Eizaguirre |first4=Alberto |last5=Moreno‐Kustner |first5=Berta |last6=Ochoa |first6=Susana |date=2019 |title=Subjective quality of life in recent onset of psychosis patients and its association with sociodemographic variables, psychotic symptoms and clinical personality traits |url=https://onlinelibrary.wiley.com/doi/10.1111/eip.12515 |journal=Early Intervention in Psychiatry |language=en |volume=13 |issue=3 |pages=525–531 |doi=10.1111/eip.12515 |issn=1751-7885}}</ref> The presence of Schizoid symptoms is also associated with a worse outcome of treatment.<ref>{{Cite journal |last=Mulder |first=Roger T. |last2=Joyce |first2=Peter R. |last3=Frampton |first3=Christopher M.A. |last4=Luty |first4=Suzanne E. |last5=Sullivan |first5=Patrick F. |date=2006-01-01 |title=Six Months of Treatment for Depression: Outcome and Predictors of the Course of Illness |url=https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.163.1.95 |url-status=live |journal=American Journal of Psychiatry |volume=163 |issue=1 |pages=95–100 |doi=10.1176/appi.ajp.163.1.95 |issn=0002-953X |archive-url=https://web.archive.org/web/20210525180444/https://pubmed.ncbi.nlm.nih.gov/16390895/ |archive-date=May 25, 2021}}</ref> [[Therapy|Treatment]] for this disorder is understudied and poorly understood.<ref>{{Cite journal |last=Keown |first=Patrick |last2=Holloway |first2=Frank |last3=Kuipers |first3=Elizabeth |date=2002-05-01 |title=The prevalence of personality disorders, psychotic disorders and affective disorders amongst the patients seen by a community mental health team in London |url=https://doi.org/10.1007/s00127-002-0533-z |url-status=live |journal=Social Psychiatry and Psychiatric Epidemiology |language=en |volume=37 |issue=5 |pages=225–229 |doi=10.1007/s00127-002-0533-z |issn=1433-9285 |archive-url=https://web.archive.org/web/20220311144334/https://link.springer.com/article/10.1007/s00127-002-0533-z |archive-date=March 11, 2022}}</ref> There is no widely accepted and approved [[psychotherapy]] or [[Psychiatric medication|medication]] for this disorder. It is one of the most poorly researched psychiatric disorders.<ref name=":22" /> Professionals may misunderstand the disorder and the client, potentially reinforcing a feeling of failure, and negatively impacting their willingness to continue to commit to treatment.<ref name=":4" /> Clinicians also tend to worry that they are incapable of properly treating the patient.<ref>{{Cite journal |last=Colli |first=Antonello |last2=Tanzilli |first2=Annalisa |last3=Dimaggio |first3=Giancarlo |last4=Lingiardi |first4=Vittorio |date=2014-01-01 |title=Patient Personality and Therapist Response: An Empirical Investigation |url=https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.2013.13020224 |url-status=live |journal=American Journal of Psychiatry |volume=171 |issue=1 |pages=102–108 |doi=10.1176/appi.ajp.2013.13020224 |issn=0002-953X |archive-url=https://web.archive.org/web/20220927182459/https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.2013.13020224 |archive-date=September 27, 2022}}</ref> It is rare for someone with this disorder to voluntarily seek treatment without a [[Comorbidity|comorbid disorder]] or pressure from family or friends.<ref>{{Cite journal |last=Kelly |first=Brendan D. |last2=Casey |first2=Patricia R. |last3=Dunn |first3=Graham |last4=Al |first4=Et |date=2007 |title=The role of personality disorder in 'difficult to reach' patients with depression: Findings from the ODIN study |url=https://researchrepository.ucd.ie/handle/10197/5863 |url-status=live |journal=European Psychiatry |language=en |volume=22 |issue=3 |pages=153–159 |doi=10.1016/j.eurpsy.2006.07.003 |archive-url=https://web.archive.org/web/20170814130103/http://researchrepository.ucd.ie/bitstream/handle/10197/5863/Kelly_Difficult_to_reach_ODIN.pdf?sequence=1 |archive-date=August 14, 2017}}</ref> In treatment, people with SzPD are usually disinterested and often minimize symptoms. Patients with SzPD may also fear losing their independence through therapy. Many schizoids will also avoid making the efforts required to establish a proper relationship with the therapist. It can also be difficult for them to open up or discuss their emotions in therapy.<ref name=":18" /> Although people with this disorder can still improve, it is unlikely they will ever experience significant joy through social interaction.<ref name=":0" />


=== Schizoid fantasy ===
== Signs and symptoms ==
{{See also|Mind-wandering}}A pathological reliance on fantasizing and [[Introspection|preoccupation with inner experience]] is often part of the [[Narcissistic withdrawal#Schizoid withdrawal|schizoid withdrawal]] from the world. Fantasy thus becomes a core component of the ''self in exile'', though fantasizing in schizoid individuals is far more complicated than a means of facilitating withdrawal.<ref name="Klein6"/>{{rp|64}} The related [[schizotypal personality disorder]] and [[schizophrenia]] are reported to have [[Creativity and mental illness|ties to creative thinking]], and it is speculated that the internal fantasy aspect of SzPD may also be reflective of this thinking.<ref>{{cite journal|last=David Schuldberg|year=2001|title=Six subclinical spectrum traits in normal creativity|journal=Creativity Research Journal|volume=13|issue=1|pages=5–16|doi=10.1207/s15326934crj1301_2|s2cid=143791841}}</ref><ref>{{Cite journal|last=George Domino|year=2002|title=Creativity and Ego Defense Mechanisms: Some Exploratory Empirical Evidence|journal=Creativity Research Journal|volume=14|issue=1|pages=17–25|doi=10.1207/S15326934CRJ1401_2|s2cid=152269910}}</ref><ref>{{cite journal |last1=Kinney |first1=Dennis K. |last2=Richards |first2=Ruth |last3=Lowing |first3=Patricia A. |last4=LeBlanc |first4=Deborah |last5=Zimbalist |first5=Morris E. |last6=Harlan |first6=Patricia |title=Creativity in Offspring of Schizophrenic and Control Parents: An Adoption Study |journal=Creativity Research Journal |date=January 2001 |volume=13 |issue=1 |pages=17–25 |doi=10.1207/S15326934CRJ1301_3 |s2cid=145560246 }}</ref>


=== Social Isolation ===
Fantasy is also a relationship with the world and with others by proxy. It is a substitute relationship, but a relationship nonetheless, characterized by idealized, defensive and compensatory mechanisms. This is self-contained and free from the dangers and anxieties associated with emotional connection to real persons and situations.<ref name="Klein6"/> Klein explains it as "an expression of the self struggling to connect to objects, albeit internal objects. Fantasy permits schizoid patients to feel connected, and yet still free from the imprisonment in relationships. In short, in fantasy one can be attached (to internal objects) and still be free."<ref name="Klein6"/> This aspect of schizoid pathology has been generously elaborated in works by R. D. Laing,<ref name="Laing1960" /> Donald Winnicott<ref>{{cite book |author=Donald Woods Winnicott |author-link=Donald Winnicott |title=Playing and Reality |url=https://books.google.com/books?id=JHMdZC08HhcC |year=1991 |publisher=Psychology Press |isbn=978-0-415-03689-4 |pages=26–38}}</ref> and Ralph Klein.<ref name="Klein6"/>{{rp|64}}
[[File:Thoma_Loneliness.jpg|thumb|194x194px|People with SzPD are often socially isolated]]
SzPD is associated with a [[Attachment theory|dismissive-avoidant attachment style]].<ref name=":18" /><ref>{{Cite journal |last=MIKULINCER |first=MARIO |last2=SHAVER |first2=PHILIP R. |date=2012 |title=An attachment perspective on psychopathology |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3266769/ |journal=World Psychiatry |volume=11 |issue=1 |pages=12 |issn=1723-8617 |pmc=3266769 |pmid=22294997 |via=[[PubMed]]}}</ref><ref>{{Cite journal |last=Westen |first=Drew |last2=Nakash |first2=Ora |last3=Thomas |first3=Cannon |last4=Bradley |first4=Rebekah |date=2006 |title=Clinical assessment of attachment patterns and personality disorder in adolescents and adults |url=https://pubmed.ncbi.nlm.nih.gov/17154736/ |journal=Journal of Consulting and Clinical Psychology |volume=74 |issue=6 |pages=1065–1085 |doi=10.1037/0022-006X.74.6.1065 |issn=0022-006X |pmid=17154736 |via=[[PubMed]]}}</ref><ref>{{Cite book |last=Sperry |first=Len |url=https://books.google.com/books?id=AMsmDAAAQBAJ&newbks=0&hl=en |title=Handbook of Diagnosis and Treatment of DSM-5 Personality Disorders: Assessment, Case Conceptualization, and Treatment, Third Edition |date=2016-05-12 |publisher=Routledge |isbn=978-1-135-01922-8 |edition=3rd |language=en}}</ref> People with this disorder will rarely maintain close relationships and often exclusively choose to participate in solitary activities.<ref>{{Cite journal |last=Candel |first=Octav |last2=Constantin |first2=Ticu |date=June 30, 2017 |title=Antisocial and Schizoid Personality Disorder Scales: Conceptual bases and preliminary findings |url=http://www.rjap.psihologietm.ro/Download/rjap191_2.pdf |url-status=live |journal=Romanian Journal of Applied Psychology |location=Romania |publisher=West University of Timisoara Publishing Hous |volume=19 |issue=1 |doi=10.24913/rjap.19.1.02 |archive-url=https://web.archive.org/web/20171202064039/http://www.rjap.psihologietm.ro/Download/rjap191_2.pdf |archive-date=December 2, 2017}}</ref><ref>{{Cite journal |last=Carvalho |first=Lucas de Francisco |last2=Salvador |first2=Ana Paula |last3=Gonçalves |first3=André Pereira |date=2020 |title=Development and Preliminary Psychometric Evaluation of the Dimensional Clinical Personality Inventory - Schizoid Personality Disorder Scale |url=http://pepsic.bvsalud.org/scielo.php?script=sci_abstract&pid=S1677-04712020000300008&lng=pt&nrm=iso&tlng=en |url-status=live |journal=Avaliação Psicológica |language=en |volume=19 |issue=3 |pages=289–297 |doi=10.15689/ap.2020.1903.16758.07 |issn=1677-0471 |archive-url=https://web.archive.org/web/20220802093122/http://pepsic.bvsalud.org/pdf/avp/v19n3/08.pdf |archive-date=August 2, 2022}}</ref><ref>{{Cite journal |last=Brieger |first=Peter |last2=Sommer |first2=Sieghard |last3=Blöink |first3=Raffaela |last4=Marneros |first4=Andreas |date=2000-09-01 |title=The Relationship Between Five-Factor Personality Measurements and ICD-10 Personality Disorder Dimensions: Results from a Sample of 229 Subjects |url=https://guilfordjournals.com/doi/10.1521/pedi.2000.14.3.282 |journal=Journal of Personality Disorders |volume=14 |issue=3 |pages=282–290 |doi=10.1521/pedi.2000.14.3.282 |issn=0885-579X}}</ref> People with Schizoid Personality disorder typically have no close friends or confidants, except for a close relative on occasions. They usually prefer hobbies and activities that do not require interaction with others.<ref>{{Cite book |last=Hazen |first=Eric |url=https://www.degruyter.com/document/doi/10.36019/9780813552347-016/html |title=Personality Disorders |last2=Hazen |first2=Eric P. |last3=Goldstein |first3=Mark A. |last4=Goldstein |first4=Myrna Chandler |date=2010-12-22 |work=Mental Health Disorders in Adolescents |publisher=Rutgers University Press |isbn=978-0-8135-5234-7 |language=en |doi=10.36019/9780813552347-016/html}}</ref><ref>{{Cite journal |last=Kwapil |first=Thomas R. |date=1998 |title=Social anhedonia as a predictor of the development of schizophrenia-spectrum disorders. |url=http://doi.apa.org/getdoi.cfm?doi=10.1037/0021-843X.107.4.558 |journal=Journal of Abnormal Psychology |language=en |volume=107 |issue=4 |pages=558–565 |doi=10.1037/0021-843X.107.4.558 |issn=1939-1846}}</ref> People with SzPD may be averse to social situations due to difficulties deriving pleasure from physical or emotional sensations, rather than [[Anhedonia|social anhedonia]].<ref>{{Cite journal |last=Ross |first=Scott R. |last2=Lutz |first2=Catherine J. |last3=Bailley |first3=Steven E. |title=Positive and Negative Symptoms of Schizotypy and the Five-Factor Model: A Domain and Facet Level Analysis |url=https://ecommons.udayton.edu/psy_fac_pub/15/?utm_source=ecommons.udayton.edu%2Fpsy_fac_pub%2F15&utm_medium=PDF&utm_campaign=PDFCoverPages |journal= |publisher=Psychology Faculty Publications |archive-url=https://web.archive.org/web/20170921232209/http://ecommons.udayton.edu/cgi/viewcontent.cgi?article=1013&context=psy_fac_pub |archive-date=September 25, 2022}}</ref><ref>{{Cite journal |last=Cicero |first=David C. |last2=Krieg |first2=Alexander |last3=Becker |first3=Theresa M. |last4=Kerns |first4=John G. |date=2016 |title=Evidence for the Discriminant Validity of the Revised Social Anhedonia Scale From Social Anxiety |url=http://journals.sagepub.com/doi/10.1177/1073191115590851 |journal=Assessment |language=en |volume=23 |issue=5 |pages=544–556 |doi=10.1177/1073191115590851 |issn=1073-1911}}</ref> One potential motivation for avoiding social situations is that they can intrude on their freedom.<ref name=":3" /><ref name=":13">{{Cite web |last=Materson |first=James |author-link=James F. Masterson |last2=Klein |first2=Ralph |date=June 23, 2015 |title=Disorders of the Self: New Therapeutic Horizons: The Masterson Approach |url=https://www.routledge.com/Disorders-of-the-Self-New-Therapeutic-Horizons-The-Masterson-Approach/Masterson-MD-Klein-MD/p/book/9781138883741 |url-status=live |archive-url=https://web.archive.org/web/20220227090417/https://www.routledge.com/Disorders-of-the-Self-New-Therapeutic-Horizons-The-Masterson-Approach/Masterson-MD-Klein-MD/p/book/9781138883741 |archive-date=February 27, 2022 |access-date=2022-09-29 |website=Routledge & CRC Press |language=en |isbn=978-113-888-374-1}}</ref> Relationships can feel suffocating for people with SzPD,<ref>{{Citation |last=Winarick |first=Daniel J. |title=Schizoid Personality Disorder |date=2020-09-18 |url=https://onlinelibrary.wiley.com/doi/10.1002/9781119547181.ch294 |work=The Wiley Encyclopedia of Personality and Individual Differences |pages=181–185 |editor-last=Carducci |editor-first=Bernardo J. |edition=1 |publisher=Wiley |language=en |doi=10.1002/9781119547181.ch294 |isbn=978-1-119-05747-5 |access-date=2022-10-02 |editor2-last=Nave |editor2-first=Christopher S. |editor3-last=Mio |editor3-first=Jeffrey S. |editor4-last=Riggio |editor4-first=Ronald E.}}</ref> and they may think of them as opportunities for entrapment.<ref name=":92" /><ref>{{Cite journal |last=Carbone |first=Jason T. |last2=Holzer |first2=Katherine J. |last3=Vaughn |first3=Michael G. |last4=DeLisi |first4=Matthew |date=2020 |title=Homicidal Ideation and Forensic Psychopathology: Evidence From the 2016 Nationwide Emergency Department Sample (NEDS) |url=https://onlinelibrary.wiley.com/doi/10.1111/1556-4029.14156 |url-status=live |journal=Journal of Forensic Sciences |language=en |volume=65 |issue=1 |pages=154–159 |doi=10.1111/1556-4029.14156 |issn=0022-1198}}</ref> Patients with this disorder are often independent and turn to themselves as sources of validation. They tend to be the happiest when in relationships in which their partner places few emotional or intimate demands on them and does not expect [[Phatic expression|phatic]] or social niceties. It is not necessarily people they want to avoid, but negative ''or'' positive emotional expectations, [[emotional intimacy]], and [[self-disclosure]].<ref name=":4" /><ref name=":02">{{Cite book |last=Philip Manfield |url=https://archive.org/details/splitselfsplitob00manf/page/204 |title=Split self/split object: understanding and treating borderline, narcissistic, and schizoid disorders. |publisher=Jason Aronson |year=1992 |isbn=978-0-87668-460-3 |pages=[https://archive.org/details/splitselfsplitob00manf/page/204 204–207]}}</ref> Patients with SzPD can feel as if close emotional bonds can be dangerous to themselves and others.<ref name=":25" /><ref name=":13" /><ref>{{Cite journal |last=Guntrip |first=H. |date=1952 |title=A Study of Fairbairn's Theory of Schizoid Reactions |url=https://onlinelibrary.wiley.com/doi/10.1111/j.2044-8341.1952.tb00791.x |journal=British Journal of Medical Psychology |language=en |volume=25 |issue=2-3 |pages=86–103 |doi=10.1111/j.2044-8341.1952.tb00791.x}}</ref> They may also have feelings of inadequacy or shame.<ref>{{Cite journal |last=Shedler |first=Jonathan |last2=Westen |first2=Drew |date=2004-08-01 |title=Refining Personality Disorder Diagnosis: Integrating Science and Practice |url=https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.161.8.1350 |url-status=live |journal=American Journal of Psychiatry |volume=161 |issue=8 |pages=1350–1365 |doi=10.1176/appi.ajp.161.8.1350 |issn=0002-953X |archive-url=https://web.archive.org/web/20211128030147/https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.161.8.1350 |archive-date=November 28, 2022}}</ref> Some people with SzPD may experience a deep desire to connect with others, but will also be terrified by the danger doing so can invoke.<ref name=":13" /><ref name="McWilliams">{{Cite journal |last=McWilliams |first=Nancy |date=2006-02-01 |title=Some Thoughts about Schizoid Dynamics |url=https://guilfordjournals.com/doi/abs/10.1521/prev.2006.93.1.1 |journal=The Psychoanalytic Review |volume=93 |issue=1 |pages=1–24 |doi=10.1521/prev.2006.93.1.1 |issn=0033-2836}}</ref> Avoidance of social situations may be a method of avoiding being hurt or rejected.<ref name=":8">{{Cite journal |last=Parpottas |first=Panagiotis |date=2012 |title=A critique on the use of standard psychopathological classifications in understanding human distress: The example of 'schizoid personality disorder'. |url=https://psycnet.apa.org/record/2012-08620-004 |url-status=live |journal=Counselling Psychology Review |language=en |location=[[Cyprus]] |volume=27 |issue=1 |archive-url=https://web.archive.org/web/20190818095303/https://psycnet.apa.org/record/2012-08620-004 |archive-date=August 18, 2019 |access-date=2022-09-26 |via=[[ResearchGate]]}}</ref><ref>{{Cite journal |last=Akhtar |first=Salman |author-link=Salman Akhtar |date=1999 |title=The distinction between needs and wishes: implications for psychoanalytic theory and technique |url=https://pubmed.ncbi.nlm.nih.gov/10367274/ |journal=Journal of the American Psychoanalytic Association |volume=47 |issue=1 |pages=130-131 |doi=10.1177/00030651990470010201 |issn=0003-0651 |pmid=10367274 |via=[[PubMed]]}}</ref> Individuals with SzPD can form relationships with others based on intellectual, physical, familial, occupational, or recreational activities, as long as there is no need for emotional intimacy [[Donald Winnicott]] explains this is because schizoid individuals "prefer to make relationships on their own terms and not in terms of the impulses of other people." Failing to attain that, they prefer isolation.<ref>{{Cite book |last=Donald Winnicott |title=The Family and Individual Development |publisher=Routledge |year=2006 |isbn=978-0415402774 |page=73}}</ref> In general, friendship among schizoids is usually limited to one person, often also schizoid, forming what has been called a union of two eccentrics; "within it – the ecstatic cult of personality, outside it – everything is sharply rejected and despised".<ref>{{Cite book |last=[[Ernst Kretschmer]] |url=https://books.google.com/books?id=77n_AgAAQBAJ |title=Body structure and character. Studies on the constitution and theory of temperaments |date=March 2013 |publisher=Ripol Classic |isbn=9785458358392 |language=ru |chapter=Chapter 10. Schizoid temperaments |chapter-url=http://sbiblio.com/biblio/archive/krechmer_stroenie/04.aspx}}</ref> Their unique lifestyle can lead to social rejection and people with SzPD are at a higher risk of facing [[bullying]] or [[homelessness]].<ref name=":112">Descriptions from [[DSM-III]] (1980) and [[DSM-5]] (2013):"[https://web.archive.org/web/20170202002500/http://displus.sk/DSM/subory/dsm3.pdf#323 Schizoid PD, Associated features (p. 310)]" and [https://books.google.com/books?id=-JivBAAAQBAJ "Schizoid PD (p. 652–655)]".</ref><ref>{{Cite journal |last=Rouff |first=Lisa |date=2000-04-01 |title=Schizoid Personality Traits Among the Homeless Mentally Ill: A Quantitative and Qualitative Report |url=https://doi.org/10.1023/A:1009470318513 |url-status=live |journal=Journal of Social Distress and the Homeless |language=en |volume=9 |issue=2 |pages=127–141 |doi=10.1023/A:1009470318513 |issn=1573-658X |archive-url=https://web.archive.org/web/20180604121422/https://link.springer.com/article/10.1023/A:1009470318513 |archive-date=June 4, 2018 |via=[[SpringerLink]]}}</ref> This social rejection can reinforce their asocial behavior.


=== Sexuality ===
=== Sexuality ===
People with this disorder usually have little interest in [[Human sexuality|sexual]] or [[Romance (love)|romantic]] acts. They rarely date or marry.<ref>{{Cite journal |last=Fitzgerald |first=Carey J. |last2=Colarelli |first2=Stephen M. |date=2009-04-01 |title=Altruism and Reproductive Limitations |url=http://journals.sagepub.com/doi/10.1177/147470490900700207 |url-status=live |journal=Evolutionary Psychology |language=en |volume=7 |issue=2 |pages=147470490900700 |doi=10.1177/147470490900700207 |issn=1474-7049 |archive-url=https://web.archive.org/web/20210518045307/https://scholarcommons.sc.edu/beaufort_socsciences_facpub/2/ |archive-date=May 18, 2021}}</ref><ref>{{Cite journal |last=Koch |first=Judith |last2=Berner |first2=Wolfgang |last3=Hill |first3=Andreas |last4=Briken |first4=Peer |date=2011 |title=Sociodemographic and Diagnostic Characteristics of Homicidal and Nonhomicidal Sexual Offenders* |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1556-4029.2011.01933.x |journal=Journal of Forensic Sciences |language=en |volume=56 |issue=6 |pages=1626–1631 |doi=10.1111/j.1556-4029.2011.01933.x |issn=0022-1198}}</ref><ref>{{Cite journal |last=Holtzman |first=Nicholas S. |last2=Strube |first2=Michael J. |date=2013-12-01 |title=Above and beyond Short-Term Mating, Long-Term Mating is Uniquely Tied to Human Personality |url=http://journals.sagepub.com/doi/10.1177/147470491301100514 |url-status=live |journal=Evolutionary Psychology |language=en |volume=11 |issue=5 |pages=147470491301100 |doi=10.1177/147470491301100514 |issn=1474-7049 |archive-url=https://web.archive.org/web/20220427000223/https://journals.sagepub.com/doi/10.1177/147470491301100514 |archive-date=April 27, 2022}}</ref> Sex often causes individuals with SzPD to feel that their personal space is being violated, and they commonly feel that [[masturbation]] or [[sexual abstinence]] is preferable to the emotional closeness they must tolerate when having sex.<ref name=":26">{{Cite journal |last=Nannarello |first=Joseph J. |year=1953 |title=Schizoid |journal=The Journal of Nervous and Mental Disease |volume=118 |issue=3 |pages=237–249 |doi=10.1097/00005053-195309000-00004 |pmid=13118367}}</ref> Significantly broadening this picture are notable exceptions of SzPD individuals who engage in occasional or even frequent sexual activities with others.<ref name=":26" /> Individuals with SzPD have long been noted to have an increased rate of unconventional sexual tendencies, though if present, these are rarely acted upon. The schizoid is often labeled asexual or presents with "a lack of sexual identity". Kernberg states that this apparent lack of sexuality does not represent a lack of sexual definition but rather a combination of several strong fixations to cope with the same conflicts. People with SzPD are often able to pursue any fantasies with content on the Internet while remaining completely unengaged with the outside world.<ref name=":18" />
People with SzPD are sometimes sexually apathetic, though they do not typically experience [[anorgasmia]]. Their preference to remain alone and detached may cause their need for sex to appear to be less than that of those who do not have SzPD. The schizoid is often labelled [[Asexuality|asexual]] or presents with "a lack of sexual identity". Kernberg states that this apparent lack of a sexuality does not represent a lack of sexual definition but rather a combination of several strong fixations to cope with the same conflicts.<ref name=":03" />{{rp|125}} Significantly broadening this picture are notable exceptions of SzPD individuals who engage in occasional or even frequent sexual activities with others.<ref name=":3" />


=== Emotions ===
Sex often causes individuals with SzPD to feel that their personal space is being violated, and they commonly feel that [[masturbation]] or [[sexual abstinence]] is preferable to the emotional closeness that they must tolerate when having sex.<ref name=":3">{{Cite journal|last=Nannarello|first=Joseph J.|year=1953|title=Schizoid|journal=The Journal of Nervous and Mental Disease|volume=118|issue=3|pages=237–249|pmid=13118367|doi=10.1097/00005053-195309000-00004}}</ref> Individuals with SzPD have long been noted to have an increased rate of unconventional sexual tendencies,{{clarify|date=November 2022}} though if present, these are rarely acted upon. People with SzPD are often able to pursue any fantasies with content on the Internet while remaining completely unengaged with the outside world.<ref name=":03" />{{rp|127}}
{{See also|Reduced affect display}}


Sensory or emotional experiences typically provide little enjoyment for people with SzPD.<ref>{{Cite journal |last=Hutsebaut |first=Joost |last2=Feenstra |first2=Dine J. |last3=Kamphuis |first3=Jan H. |date=2016 |title=Development and Preliminary Psychometric Evaluation of a Brief Self-Report Questionnaire for the Assessment of the DSM–5 level of Personality Functioning Scale: The LPFS Brief Form (LPFS-BF). |url=http://doi.apa.org/getdoi.cfm?doi=10.1037/per0000159 |url-status=live |journal=Personality Disorders: Theory, Research, and Treatment |language=en |volume=7 |issue=2 |pages=192–197 |doi=10.1037/per0000159 |issn=1949-2723 |archive-url=https://web.archive.org/web/20220926185309/https://psycnet.apa.org/doiLanding?doi=10.1037%2Fper0000159 |archive-date=September 26, 2022}}</ref><ref>{{Cite journal |last=Joyce |first=Peter R. |last2=McKenzie |first2=Janice M. |last3=Carter |first3=Janet D. |last4=Rae |first4=Alma M. |last5=Luty |first5=Suzanne E. |last6=Frampton |first6=Christopher M. A. |last7=Mulder |first7=Roger T. |date=2007 |title=Temperament, character and personality disorders as predictors of response to interpersonal psychotherapy and cognitive-behavioural therapy for depression |url=https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/temperament-character-and-personality-disorders-as-predictors-of-response-to-interpersonal-psychotherapy-and-cognitivebehavioural-therapy-for-depression/0F6337D837512F2223A7A3C249E68834 |journal=The British Journal of Psychiatry |language=en |volume=190 |issue=6 |pages=503–508 |doi=10.1192/bjp.bp.106.024737 |issn=0007-1250}}</ref> They rarely display strong emotions or react to anything.<ref>{{Cite journal |last=Brotto |first=Lori A. |last2=Knudson |first2=Gail |last3=Inskip |first3=Jess |last4=Rhodes |first4=Katherine |last5=Erskine |first5=Yvonne |date=2010-06-01 |title=Asexuality: A Mixed-Methods Approach |url=https://doi.org/10.1007/s10508-008-9434-x |url-status=live |journal=Archives of Sexual Behavior |language=en |volume=39 |issue=3 |pages=599–618 |doi=10.1007/s10508-008-9434-x |issn=1573-2800 |archive-url=https://web.archive.org/web/20220609011139/https://link.springer.com/article/10.1007/s10508-008-9434-x |archive-date=June 9, 2022}}</ref> People with SzPD can have difficulty expressing themselves and seem to be directionless or passive.<ref name=":1" /> Individuals with SzPD can also experience [[anhedonia]].<ref>{{Cite journal |last=Martin |first=Elizabeth A. |last2=Cicero |first2=David C. |last3=Kerns |first3=John G. |date=2012 |title=Social anhedonia, but not positive schizotypy, is associated with poor affective control |url=https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.719.2083&rep=rep1&type=pdf |journal=Personality Disorders |volume=3 |issue=3 |pages=263–272 |doi=10.1037/a0024488 |issn=1949-2723 |pmid=22452767}}</ref> They can also have difficulty understanding others' emotions and [[Social cue|social cues]].<ref>{{Cite journal |last=Smith |first=Adam |date=2006-01-01 |title=Cognitive Empathy and Emotional Empathy in Human Behavior and Evolution |url=https://doi.org/10.1007/BF03395534 |url-status=live |journal=The Psychological Record |language=en |volume=56 |issue=1 |pages=3–21 |doi=10.1007/BF03395534 |issn=2163-3452 |archive-url=https://web.archive.org/web/20220904080718/https://link.springer.com/article/10.1007/BF03395534 |archive-date=September 4, 2022}}</ref><ref>{{Cite journal |last=Booules-Katri |first=Tereza-Maria |last2=Pedreño |first2=Carla |last3=Navarro |first3=Jose-Blás |last4=Pamias |first4=Montserrat |last5=Obiols |first5=Jordi E. |date=2019-08-01 |title=Theory of Mind (ToM) Performance in High Functioning Autism (HFA) and Schizotypal–Schizoid Personality Disorders (SSPD) Patients |url=https://doi.org/10.1007/s10803-019-04058-1 |journal=Journal of Autism and Developmental Disorders |language=en |volume=49 |issue=8 |pages=3376–3386 |doi=10.1007/s10803-019-04058-1 |issn=1573-3432}}</ref><ref>{{Cite journal |last=Gagliardini |first=Giulia |last2=Gullo |first2=Salvatore |last3=Caverzasi |first3=Edgardo |last4=Boldrini |first4=Annalisa |last5=Blasi |first5=Stefano |last6=Colli |first6=Antonello |date=2018-12-18 |title=Assessing mentalization in psychotherapy: first validation of the Mentalization Imbalances Scale |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7451352/ |journal=Research in Psychotherapy : Psychopathology, Process, and Outcome |volume=21 |issue=3 |pages=339 |doi=10.4081/ripppo.2018.339 |issn=2499-7552 |pmc=7451352 |pmid=32913774 |via=[[PubMed]]}}</ref> It can be hard for people with SzPD to assess the impact of their actions in social situations.<ref name="Laing1960">{{cite book |last=Ronald D. Laing |title=The Divided Self: an Existential Study in Sanity and Madness |publisher=[[Penguin Books]] |year=1965 |isbn=9780140207347 |location=Harmondsworth, Middlesex; Baltimore |pages=82–100 |chapter=The Inner Self in the Schizoid Condition |oclc=5212085 |author-link=R. D. Laing |chapter-url=https://books.google.com/books?id=4JT-12rMtJsC&pg=PT87}}</ref><ref>{{Cite book |last=Veague |first=Heather Barnett |url=https://books.google.com/books?id=EGZZgqcIkm0C&newbks=0&hl=en |title=Personality Disorders |last2=Collins |first2=Christine Elaine |date=2007 |publisher=Infobase Publishing |isbn=978-1-4381-1839-0 |pages=21 |language=en}}</ref> People with this condition are often indifferent towards criticism or praise and can appear distant, aloof, or uncaring to others.<ref>{{Cite journal |last=Wang |first=Fenghua |last2=Chen |first2=Wanzhen |last3=Huang |first3=Jingyi |last4=Xu |first4=Peiwei |last5=He |first5=Wei |last6=Chai |first6=Hao |last7=Zhu |first7=Junpeng |last8=Yu |first8=Wenjun |last9=Chen |first9=Li |last10=Wang |first10=Wei |date=2011-07-30 |title=Preliminary study of relationships between hypnotic susceptibility and personality disorder functioning styles in healthy volunteers and personality disorder patients |url=https://doi.org/10.1186/1471-244X-11-121 |url-status=live |journal=BMC Psychiatry |volume=11 |issue=1 |pages=121 |doi=10.1186/1471-244X-11-121 |issn=1471-244X |pmc=PMC3162494 |pmid=21801440 |archive-url=https://web.archive.org/web/20211204204418/https://bmcpsychiatry.biomedcentral.com/articles/10.1186/1471-244X-11-121 |archive-date=December 4, 2021}}</ref> They may avoid others and expressing themselves as a method of keeping others distant and preventing themselves from being hurt.<ref>{{Cite journal |last=Fossati |first=Andrea |date=2012 |title=Shut in or split up? A commentary on Dr. Nirestean and colleagues' ‘Schizoid personality disorder-the peculiarities of their interpersonal relationships and existential roles’: Shut in or split up? |url=https://onlinelibrary.wiley.com/doi/10.1002/pmh.1179 |journal=Personality and Mental Health |language=en |volume=6 |issue=1 |pages=77–82 |doi=10.1002/pmh.1179 |via=[[Wiley Online Library]]}}</ref><ref name=":24" /><ref name=":8" /> Remaining alone and expressionless can feel safe and comfortable for people with SzPD.<ref>{{Cite journal |last=Little |first=Ray |date=2021-03-12 |title=Engaging With the Schizoid Compromise: A Response to Erskine’s “Relational Withdrawal, Attunement to Silence: Psychotherapy of the Schizoid Process” |url=http://integrative-journal.com/index.php/ijip/article/view/165 |url-status=live |journal=International Journal of Integrative Psychotherapy |language=en |volume=11 |issue=1 |pages=29–54 |issn=2156-9703 |archive-url=https://web.archive.org/web/20211127003523/http://integrative-journal.com/index.php/ijip/article/view/165 |archive-date=November 27, 2021}}</ref> Expressing themselves can make them feel uncomfortable and afraid of failure or shame.<ref name=":1" /> People with SzPD may feel inadequate and can be sensitive,<ref>{{Cite journal |last=Akhtar |first=Salman |date=1987-10-01 |title=Schizoid Personality Disorder: A Synthesis of Developmental, Dynamic, and Descriptive Features |url=https://psychotherapy.psychiatryonline.org/doi/10.1176/appi.psychotherapy.1987.41.4.499 |journal=American Journal of Psychotherapy |volume=41 |issue=4 |pages=499–518 |doi=10.1176/appi.psychotherapy.1987.41.4.499 |issn=0002-9564}}</ref> although they have difficulty expressing it.<ref name=":152">{{Cite journal |last=Thylstrup |first=Birgitte |last2=Hesse |first2=Morten |date=2009-04-01 |title=“I am not Complaining”—Ambivalence Construct in Schizoid Personality Disorder |url=https://psychotherapy.psychiatryonline.org/doi/10.1176/appi.psychotherapy.2009.63.2.147 |url-status=live |journal=American Journal of Psychotherapy |volume=63 |issue=2 |pages=147–167 |doi=10.1176/appi.psychotherapy.2009.63.2.147 |issn=0002-9564 |pmid=19711768 |archive-url=https://web.archive.org/web/20220314071415/https://psychotherapy.psychiatryonline.org/doi/10.1176/appi.psychotherapy.2009.63.2.147 |archive-date=March 14, 2022 |via=Psychiatry Online}}</ref><ref name=":18" /> [[Alexithymia]], or difficulties understanding one's own emotions is common amongst people with SzPD.<ref>{{cite book |last1=Taylor |first1=Graeme J |title=Disorders of Affect Regulation: Alexithymia in Medical and Psychiatric Illness |last2=Bagby |first2=R. Michael |last3=Parker |first3=James DA |publisher=Cambridge University Press |year=1997 |isbn=978-0-521-45610-4 |location=Cambridge |pp=162-165}}</ref><ref>{{Cite book |url=https://www.degruyter.com/document/doi/10.1515/9783110319453.145/html |title=Chapter 5. Hope and Alexithymia |date=2013-05-02 |publisher=De Gruyter |isbn=978-3-11-031945-3 |pages=153-157 |language=en |doi=10.1515/9783110319453.145/html}}</ref><ref>{{Cite journal |last=Coolidge |first=Frederick L. |last2=Estey |first2=Alisa J. |last3=Segal |first3=Daniel L. |last4=Marle |first4=Peter D. |date=2013-02-01 |title=Are alexithymia and schizoid personality disorder synonymous diagnoses? |url=https://www.sciencedirect.com/science/article/pii/S0010440X12001344 |journal=Comprehensive Psychiatry |language=en |volume=54 |issue=2 |pages=141–148 |doi=10.1016/j.comppsych.2012.07.005 |issn=0010-440X}}</ref> This leads to them isolating themselves to avoid the discomfort and stimulation emotional experiences offer.<ref name=":18" /> According to [[Harry Guntrip|Guntrip]], Klein, and others, people with SzPD may possess a hidden sense of superiority and lack dependence on other people's opinions. This is very different from the grandiosity seen in [[narcissistic personality disorder]], which is described as "burdened with envy" and with a desire to destroy or put down others. Additionally, schizoids do not go out of their way to achieve social validation. Unlike the narcissist, the schizoid will often keep their creations private to avoid unwelcome attention or the feeling that their ideas and thoughts are being appropriated by the public.<ref name=":18" /> When forced to rely on others a person with SzPD may feel panic or terror.<ref name=":18" />
===Clinical classifications===
[[File:Depersonalization.jpg|thumb|182x182px|It is common for people with SzPD to experience depersonalization]]
====Akhtar's profile====
[[Salman Akhtar]] provided a comprehensive phenomenological profile of SzPD in which classic and contemporary descriptive views are synthesized with psychoanalytic observations. Akhtar states that his profile has several advantages over the DSM in terms of maintaining historical continuity of the use of the word ''schizoid'', valuing depth and complexity over descriptive oversimplification and helping to provide a more meaningful [[differential diagnosis]] of SzPD from other personality disorders.<ref name="Akhtar" />


=== Feelings of unreality ===
This profile is summarized in the table reproduced below that lists clinical features that involve six areas of psychosocial functioning and are organized by "overt" and "covert" manifestations, intended to denote seemingly contradictory aspects that may simultaneously be present in an individual.<ref name="Akhtar" /> These designations do not necessarily imply their conscious or unconscious existence, nor do they imply outward behavior compared to internal thought processes. The covert characteristics are not immediately apparent by definition and difficult to discern. Additionally, the lack of data on the frequency of many of the features makes their relative diagnostic weight difficult to distinguish at this time.
Patients with SzPD often feel unreal, empty,<ref name=":4" /><ref name="McWilliams" /> and that they are separate from their own emotions.<ref>{{Cite journal |last=Newberry |first=Michelle T. |title=An exploration of the trauma histories, dissociative experiences and psychopathic features of murderers |url=https://core.ac.uk/outputs/30339635 |url-status=live |journal= |archive-url=https://web.archive.org/web/20220925141216/https://core.ac.uk/outputs/30339635 |archive-date=September 25, 2022}}</ref> They tend to perceive themselves as fundamentally different from others and can believe themselves to be fundamentally unlikeable.<ref name=":13" /><ref>{{Cite journal |last=Fountoulakis |first=KN |last2=Iacovides |first2=A. |last3=Ioannidou |first3=Ch |last4=Bascialla |first4=F. |last5=Nimatoudis |first5=I. |last6=Kaprinis |first6=G. |last7=Janca |first7=A. |last8=Dahl |first8=A. |date=2002-05-17 |title=Reliability and cultural applicability of the Greek version of the International Personality Disorders Examination. |url=https://doi.org/10.1186/1471-244X-2-6 |url-status=live |journal=BMC Psychiatry |volume=2 |issue=1 |pages=6 |doi=10.1186/1471-244X-2-6 |issn=1471-244X |pmc=PMC116573 |pmid=12019033 |archive-url=https://web.archive.org/web/20220623110650/https://bmcpsychiatry.biomedcentral.com/track/pdf/10.1186/1471-244X-2-6.pdf |archive-date=June 23, 2022}}</ref> Other people often seem strange and incomprehensible to a person with SzPD. Reality can feel unenjoyable and uninteresting to people with SzPD. They have difficulty finding motivation and lack ambition.<ref>{{Cite journal |last=Carvalho |first=Lucas |last2=Salvador |first2=A. |last3=Gonçalves |first3=A. |date=2020-05-15 |title=Development and Preliminary Psychometric Evaluation of the Dimensional Clinical Personality Inventory - Schizoid Personality Disorder Scale |url=http://discovery.researcher.life/article/development-and-preliminary-psychometric-evaluation-of-the-dimensional-clinical-personality-inventory-schizoid-personality-disorder-scale/13bb6f6c10b7316bbf0c37a5b62548ef |url-status=live |journal=Revista Avaliação Psicológica |language=en |volume=19 |doi=10.15689/ap.2020.1903.16758.07 |archive-url=https://web.archive.org/web/20210829050342/https://www.semanticscholar.org/paper/Development-and-Preliminary-Psychometric-Evaluation-Carvalho-Salvador/8159c2f2e16c3919f876ebcf8d917e076c480fab |archive-date=August 29, 2022}}</ref><ref>{{Cite journal |last=Mullins-Sweatt |first=Stephanie |date=2004-06-04 |title=Personality Disorders as Maladaptive Variants of General Personality Traits: A Subclinical Approach |url=https://scholarworks.moreheadstate.edu/msu_theses_dissertations/703 |url-status=live |journal=Morehead State Theses and Dissertations |archive-url=https://web.archive.org/web/20220925122409/https://scholarworks.moreheadstate.edu/msu_theses_dissertations/703/ |archive-date=September 25, 2022 |access-date=September 25, 2022}}</ref><ref>{{Cite journal |last=Svrakic |first=Dragan |last2=Divac-Jovanovic |first2=Mirjana |last3=Azhar |first3=Naazia |title=An Integrative Model and Dynamic Nosology of Personality Disorder: Part 2: Symptoms-Based Pharmacotherapy |url=https://hrcak.srce.hr/file/324300 |url-status=live |journal=Psychiatria Danubina |location=[[Zagreb]], [[Croatia]] |volume=31 |pages=2-17 |doi=10.24869/psyd.2019.2 |archive-url=https://web.archive.org/web/20220618034828/https://hrcak.srce.hr/file/324300 |archive-date=June 18, 2022}}</ref> Patients with SzPD often feel as if they are "going through the motions" or that "life passes them by."<ref name=":12">{{Cite journal |last=Hayward |first=Brent A. |date=2007 |title=Cluster A personality disorders: Considering the 'odd-eccentric' in psychiatric nursing |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1447-0349.2006.00439.x |journal=International Journal of Mental Health Nursing |language=en |volume=16 |issue=1 |pages=15–21 |doi=10.1111/j.1447-0349.2006.00439.x |issn=1445-8330}}</ref><ref>{{Cite book |last=Hafemeister |first=Thomas L. |url=https://www.degruyter.com/document/doi/10.18574/nyu/9781479804856.003.0002/html |title=Mental Disorders and Criminal Behavior |date=2019-02-05 |work=Criminal Trials and Mental Disorders |publisher=New York University Press |isbn=978-1-4798-5075-4 |pages=36-37 |language=en |doi=10.18574/nyu/9781479804856.003.0002/html}}</ref><ref>{{Cite journal |last=Gerson |first=Gal |date=April 29, 2021 |title=Fairbairn, Winnicott, and Guntrip on the social significance of schizoids |url=https://journals.sagepub.com/doi/abs/10.1177/09526951211008078#:~:text=Fairbairn%2C%20Winnicott%2C%20and%20Guntrip%20described,the%20contemporary%20welfare%20state%20ideology. |journal=History of the Human Sciences |language=en |volume=35 |issue=3-4 |pages=144-167 |doi=10.1177/09526951211008078 |issn=0952-6951 |via=[[SAGE publications]]}}</ref> Many describe feeling as if they are observing life from a distance.<ref>{{cite book |last=Jeffrey J. Magnavita |url=https://books.google.com/books?id=zlFVfzH8orMC&pg=PA236 |title=Restructuring Personality Disorders: A Short-Term Dynamic Approach |publisher=The Guilford Press |year=1997 |isbn=978-1-57230-185-6 |location=New York |page=237}}</ref> [[Aaron Beck]] and his colleagues report that people with SzPD seem comfortable with their aloof lifestyle and consider themselves observers, rather than participants in the world around them. But they also mention that many of their schizoid patients recognize themselves as socially deviant (or even defective) when confronted with the different lives of ordinary people – especially when they read books or see movies focusing on relationships. Even when schizoid individuals may not long for closeness, they can become weary of being "on the outside, looking in". These feelings may lead to depression, [[depersonalization]], or [[derealization]].<ref name=":13" /><ref name=":12" /><ref name=":18" /> If they do, schizoid people often experience feeling "like a robot" or "going through life in a dream".<ref name="beckfreeman2">{{cite book |author1=Aaron T. Beck |title=Cognitive Therapy of Personality Disorders |author2=Arthur Freeman |publisher=The Guilford Press |year=1990 |isbn=9780898624342 |edition=1st |pages=125 (Millon),127–129 (cognitive therapy conceptualization) |chapter=Chapter 7 Schizoid and Schizotypal PD (p.120-146) |oclc=906420553 |author1-link=Aaron T. Beck}}</ref> People with SzPD may try to avoid all physical activity in order to become nobody and disconnect from reality. This can lead to the patient spending a large quantity of time sleeping and ignoring bodily functions such as [[hygiene]].<ref name=":18" /> For people with SzPD,


=== Internal fantasy ===
{{See also|Maladaptive daydreaming}}

Although this disorder does not affect the patient's capacity to understand reality, they may engage in excessive [[Daydream|daydreaming]] and [[introspection]].<ref name=":2" /><ref>{{Cite book |last=Winnicott |first=Donald Woods |url=https://books.google.com/books?id=JHMdZC08HhcC |title=Playing and Reality |date=1991 |publisher=Psychology Press |year=1991 |isbn=978-0-415-03689-4 |pages=26-28 |language=en}}</ref><ref>{{Cite journal |last=Madonna |first=John |date=December 1, 2021 |title=Sensitivity, isolation, and loneliness in the treatment of schizoid personality disorder |journal=Modern Psychoanalysis |volume=45 |issue=2 |pages=155-175 |via=[[EBSCO]]}}</ref> Their daydreams can grow to consume most of their lives. Real life can become secondary to their [[Fantasy (psychology)|fantasy]],<ref name=":7">{{Cite journal |last=Chadwick |first=Peter |date=December 18, 2013 |title=Peer-Professional First Person Account: Before Psychosis—Schizoid Personality From the Inside |url=https://academic.oup.com/crawlprevention/governor?content=%2fschizophreniabulletin%2farticle%2f40%2f3%2f483%2f1905514 |url-status=live |journal=[[Schizophrenia Bulletin]] |volume=40 |issue=3 |doi=10.1093/schbul/sbt182 |archive-url=https://web.archive.org/web/20220728194035/https://academic.oup.com/schizophreniabulletin/article/40/3/483/1905514 |archive-date=July 28, 2022 |access-date=2022-09-26 |via=[[Oxford Academic]]}}</ref> and they can have complex lives and relationships which exist entirely inside of their internal fantasy. These daydreams may a defense mechanism to protect the patient from the outside world and its difficulties.<ref name=":25" /><ref name=":13" /><ref>{{Cite journal |last=Ceroni |first=Mara Luiza Vieira |last2=Abude |first2=Cláudia |date=2019-04-01 |title=Compulsions and Personality Disorders: Homicides and Suicides: a Social Health Issue Based on Bioenergetic Analysis |url=https://bioenergetic-analysis.com/article/view/0743-4804-2019-29-79 |url-status=live |journal=Bioenergetic Analysis |language=en |volume=29 |issue=1 |pages=79–97 |doi=10.30820/0743-4804-2019-29-79 |issn=2747-8882 |archive-url=https://web.archive.org/web/20211026181509/https://bioenergetic-analysis.com/article/view/0743-4804-2019-29-79 |archive-date=October 29, 2021}}</ref> Common themes in their internal fantasies are [[omnipotence]] and [[grandiosity]].<ref name=":18" /> The related [[schizotypal personality disorder]] and [[schizophrenia]] are reported to have [[Creativity and mental illness|ties to creative thinking]], and it is speculated that the internal fantasy aspect of SzPD may also be reflective of this thinking.<ref>{{cite journal |last=David Schuldberg |year=2001 |title=Six subclinical spectrum traits in normal creativity |journal=Creativity Research Journal |volume=13 |issue=1 |pages=5–16 |doi=10.1207/s15326934crj1301_2 |s2cid=143791841}}</ref><ref>{{Cite journal |last=George Domino |year=2002 |title=Creativity and Ego Defense Mechanisms: Some Exploratory Empirical Evidence |journal=Creativity Research Journal |volume=14 |issue=1 |pages=17–25 |doi=10.1207/S15326934CRJ1401_2 |s2cid=152269910}}</ref><ref>{{Cite journal |last1=Kinney |first1=Dennis K. |last2=Richards |first2=Ruth |year=2001 |title=Creativity in Offspring of Schizophrenic and Control Parents: An Adoption Study |url=https://www.researchgate.net/publication/233244470 |journal=Creativity Research Journal |volume=13 |issue=1 |pages=17–25 |doi=10.1207/S15326934CRJ1301_3 |s2cid=145560246}}</ref> Alternatively, there has been an especially large contribution of people with schizoid symptoms to science and theoretical areas of knowledge, including [[mathematics]], [[physics]], [[economics]], etc. At the same time, people with SzPD are helpless at many practical activities because of their symptoms.<ref>{{Cite book |last=Белорусов |first=Сергей |url=https://books.google.com/books?id=Xw_JDgAAQBAJ&pg=PT215 |title=Очерки душевной патологии. И возможности ее коррекции соотносительно с духовным измерением бытия |date=2017-09-05 |publisher=Litres |isbn=9785040548330 |language=ru |quote=Especially important is the contribution of schizoid scientists in the theoretical fields of knowledge: mathematics, physics, economics. At the same time, schizoids are absolutely helpless in practical activities.}}</ref>

=== Suicide and Self-harm ===
Symptoms of SzPD such as isolation and the blunted affect put people with Schizoid Personality disorder at a higher risk of [[suicide]] and [[Self-harm|non-suicidal self-harm]].<ref name="PsychiatriaDanubina2">{{cite journal |last1=Attademo |first1=Luigi |last2=Bernardini |first2=Francesco |last3=Spatuzzi |first3=Roberta |date=2021 |title=Suicidality in individuals with schizoid personality disorder or traits: a clinical mini-review of a probably underestimated issue |url=https://www.psychiatria-danubina.com/UserDocsImages/pdf/dnb_vol33_no3/dnb_vol33_no3_261.pdf |url-status=live |journal=Psychiatria Danubina |volume=33 |issue=3 |pages=261–265 |doi=10.24869/psyd.2021.261 |pmid=34795159 |archive-url=https://web.archive.org/web/20220922203658/https://www.psychiatria-danubina.com/UserDocsImages/pdf/dnb_vol33_no3/dnb_vol33_no3_261.pdf |archive-date=September 22, 2022 |s2cid=244385145}}</ref><ref>{{Cite journal |last=Del Bello |first=Valentina |last2=Verdolini |first2=Norma |last3=Pauselli |first3=Luca |last4=Attademo |first4=Luigi |last5=Bernardini |first5=Francesco |last6=Quartesan |first6=Roberto |last7=Moretti |first7=Patrizia |date=2015 |title=Personality and psychotic symptoms as predictors of self-harm and attempted suicide |url=https://pubmed.ncbi.nlm.nih.gov/26417781/ |url-status=live |journal=Psychiatria Danubina |volume=27 Suppl 1 |pages=S285–291 |issn=0353-5053 |pmid=26417781 |archive-url=https://web.archive.org/web/20220618023120/https://hrcak.srce.hr/file/384165 |archive-date=June 18, 2022}}</ref><ref>{{Cite journal |last=Levi |first=Yossi |last2=Horesh |first2=Netta |last3=Fischel |first3=Tzvi |last4=Treves |first4=Ilan |last5=Or |first5=Evgenia |last6=Apter |first6=Alan |date=2008-12-01 |title=Mental pain and its communication in medically serious suicide attempts: An “impossible situation” |url=https://www.sciencedirect.com/science/article/pii/S016503270800102X |url-status=live |journal=Journal of Affective Disorders |language=en |volume=111 |issue=2 |pages=244–250 |doi=10.1016/j.jad.2008.02.022 |issn=0165-0327 |archive-url=https://web.archive.org/web/20220617012716/https://pubmed.ncbi.nlm.nih.gov/18436309/ |archive-date=June 17, 2022}}</ref> This may be because their reduced capacities for emotion prevent them from properly dealing with strife. Their solitary nature may also contribute by preventing them from finding relief in relationships.<ref name=":142">{{Cite journal |last1=Levi-Belz |first1=Y. |last2=Gvion |first2=Y. |last3=Levi |first3=U. |last4=Apter |first4=A. |year=2019 |title=Beyond the mental pain: A case-control study on the contribution of schizoid personality disorder symptoms to medically serious suicide attempts |url=https://www.sciencedirect.com/science/article/pii/S0010440X19300136?via%3Dihub |url-status=live |journal=Comprehensive Psychiatry |volume=90 |pages=102–109 |doi=10.1016/j.comppsych.2019.02.005 |pmid=30852349 |archive-url=https://web.archive.org/web/20210606054253/https://www.sciencedirect.com/science/article/pii/S0010440X19300136?via%3Dihub |archive-date=June 6, 2022 |via=[[Elsevier Science Direct]] |doi-access=free}}</ref> Demonstrative suicides or suicide blackmail, as seen in [[cluster B personality disorders]] such as [[Borderline personality disorder|borderline]], [[Histrionic personality disorder|histrionic]], or [[Antisocial personality disorder|antisocial]], are extremely rare among schizoid individuals.<ref name=":20">{{Cite journal |last1=Анатольевна |first1=Панченко Евгения |last2=Сергеевич |first2=Положий Борис |year=2011 |title=Расстройства Личности у Пациентов, Совершивших Суицидальные Попытки |trans-title=Personality Disorders in Patients Who Have Committed Suicide Attempts |url=https://cyberleninka.ru/article/n/rasstroystva-lichnosti-u-patsientov-sovershivshih-suitsidalnye-popytki |journal=Российский психиатрический журнал |issue=3 |pages=48–51 |issn=1560-957X}}</ref> As in other clinical mental health settings, among suicidal inpatients, individuals with SzPD are not as well-represented as some other groups. A 2011 study on suicidal inpatients at a Moscow hospital found that schizoids were the least common patients, while those with cluster B personality disorders were the most common.<ref name=":20" />

=== Low weight ===
A study that looked at the [[body mass index]] (BMI) of a sample of both male adolescents diagnosed with SzPD and those diagnosed with Asperger syndrome found that the BMI of all patients was significantly below normal. Clinical records indicated abnormal eating behavior by some patients. Some patients would only eat when alone and refused to eat out. Restrictive diets and [[Hypochondriasis|fears of disease]] were also found. It was suggested that the anhedonia of SzPD may also cover eating, leading schizoid individuals to not enjoy it.<ref>{{Cite journal |last=Hebebrand |first=J. |last2=Hennighausen |first2=K. |last3=Nau |first3=S. |last4=Himmelmann |first4=G. W. |last5=Schulz |first5=E. |last6=Schäfer |first6=H. |last7=Remschmidt |first7=H. |date=1997 |title=Low body weight in male children an adolescents with schizoid personality disorder or Asperger's disorder |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1600-0447.1997.tb09906.x |journal=Acta Psychiatrica Scandinavica |language=en |volume=96 |issue=1 |pages=64–67 |doi=10.1111/j.1600-0447.1997.tb09906.x |issn=0001-690X |via=[[Wiley Online Library]]}}</ref> Alternatively, it was suggested that schizoid individuals may not feel hunger as strongly as others or not respond to it, a certain withdrawal "from themselves".<ref name=":162" />

=== Substance abuse ===
Very little data exists for rates of [[substance use disorder]] among people with SzPD, but existing studies suggest they are less likely to have [[substance abuse]] problems than the general population. One study found that significantly fewer boys with SzPD had alcohol problems than a control group of non-schizoids.<ref name=":182">{{Cite journal |last1=Wolff |first1=S. |last2=Cull |first2=A. |date=August 1986 |title='Schizoid' personality and antisocial conduct: a retrospective case not study |journal=Psychological Medicine |volume=16 |issue=3 |pages=677–687 |doi=10.1017/S0033291700010424 |issn=0033-2917 |pmid=3763781 |s2cid=35166577}}</ref> Another study evaluating personality disorder profiles in substance abusers found that substance abusers who showed schizoid symptoms were more likely to abuse one substance rather than many, in contrast to other personality disorders such as [[Borderline personality disorder|borderline]], [[Antisocial personality disorder|antisocial]], or [[Histrionic personality disorder|histrionic]], which were more likely to abuse many.<ref>{{Cite journal |last1=Skinstad |first1=Anne Helene |last2=Swain |first2=Annette |date=2001-01-01 |title=Comorbidity in a Clinical Sample of Substance Abusers |journal=The American Journal of Drug and Alcohol Abuse |volume=27 |issue=1 |pages=45–64 |doi=10.1081/ADA-100103118 |issn=0095-2990 |pmid=11373036 |s2cid=2619787}}</ref> American psychotherapist Sharon Ekleberry states that the impoverished social connections experienced by people with SzPD limit their exposure to the drug culture and that they have limited inclination to learn how to do illegal drugs. Describing them as "highly resistant to influence", she additionally states that even if they could access illegal drugs, they would be disinclined to use them in public or social settings, and because they would be more likely to use alcohol or cannabis alone than for social [[disinhibition]], they would not be particularly vulnerable to negative consequences in early use.<ref name=":52">{{Cite book |last=Sharon C. Ekleberry |title=Integrated Treatment for Co-Occurring Disorders: Personality Disorders and Addiction |publisher=Routledge |year=2008 |isbn=978-0789036933 |pages=31–32 |chapter=Cluster A - Schizoid Personality Disorder and Substance Use Disorders |chapter-url=https://books.google.com/books?id=O5HY1xcfjEcC&pg=PA31}}</ref> Other studies have found that they have a higher risk of developing substance abuse issues than normal people.<ref>{{Cite journal |last=Patel |first=Nisheet |last2=Sharma |first2=Himanshu |last3=Mahida |first3=Ankur |last4=Mistry |first4=Hansal |date=2022 |title=Relationship of alcohol use pattern with locus of control and impulsivity: A cross-sectional study in hospitalized alcohol use disorder patients in Western India |url=https://journals.lww.com/jfmpc/Fulltext/2022/03000/Relationship_of_alcohol_use_pattern_with_locus_of.27.aspx |url-status=live |journal=Journal of Family Medicine and Primary Care |language=en-US |volume=11 |issue=3 |pages=987–993 |doi=10.4103/jfmpc.jfmpc_1181_21 |issn=2249-4863 |archive-url=https://web.archive.org/web/20220927164327/https://journals.lww.com/jfmpc/Fulltext/2022/03000/Relationship_of_alcohol_use_pattern_with_locus_of.27.aspx |archive-date=September 27, 2022}}</ref><ref>{{Cite journal |last=Graham |first=Danzer |year=2015 |title=Integrating Object Relations and Alcoholics - ProQuest |url=https://www.proquest.com/docview/1801608616?fromopenview=true&pq-origsite=gscholar |url-status=live |journal=Journal of Theory Construction & Testing |language=en |volume=19 |issue=2 |access-date=2022-09-30 |via=[[Proquest]]}}</ref><ref>{{Cite journal |last=Kosson |first=David S. |last2=Blackburn |first2=Ronald |last3=Byrnes |first3=Katherine A. |last4=Park |first4=Sohee |last5=Logan |first5=Caroline |last6=Donnelly |first6=John P. |date=2008-02-25 |title=Assessing Interpersonal Aspects of Schizoid Personality Disorder: Preliminary Validation Studies |url=https://www.tandfonline.com/doi/abs/10.1080/00223890701845427 |url-status=live |journal=Journal of Personality Assessment |volume=90 |issue=2 |pages=185–196 |doi=10.1080/00223890701845427 |issn=0022-3891 |pmid=18444113 |archive-url=https://web.archive.org/web/20181125204603/http://parklab.vanderbilt.edu/Kosson_schizoid_2008.pdf |archive-date=November 25, 2018}}</ref> Despite this, people with SzPD are at a lower risk of substance abuse issues than other [[Personality disorder|Personality disorders]].<ref>{{Cite journal |last=DiClemente |first=Carlo C. |last2=Prochaska |first2=James O. |date=1982-01-01 |title=Self-change and therapy change of smoking behavior: A comparison of processes of change in cessation and maintenance |url=https://www.sciencedirect.com/science/article/pii/0306460382900387 |url-status=live |journal=Addictive Behaviors |language=en |volume=7 |issue=2 |pages=133–142 |doi=10.1016/0306-4603(82)90038-7 |issn=0306-4603 |archive-url=https://web.archive.org/web/20210812233113/https://www.sciencedirect.com/science/article/abs/pii/0306460382900387 |archive-date=August 12, 2021}}</ref><ref>{{Cite journal |last=Ayerbe |first=Luis |last2=Forgnone |first2=Ivo |last3=Foguet-Boreu |first3=Quintí |last4=González |first4=Esteban |last5=Addo |first5=Juliet |last6=Ayis |first6=Salma |date=2018-03-01 |title=Disparities in the management of cardiovascular risk factors in patients with psychiatric disorders: a systematic review and meta-analysis |url=http://dx.doi.org/10.1017/s0033291718000302 |journal=Psychological Medicine |volume=48 |issue=16 |pages=2693–2701 |doi=10.1017/s0033291718000302 |issn=0033-2917}}</ref> They may form relationships with their substances as a substitute for human contact or to cope with emotional issues.<ref>{{Cite journal |last=El Rasheed |first=Amany Haroun |last2=Elserafy |first2=Doha Moustafa |last3=Marey |first3=Mennatullah Ali |last4=Hashem |first4=Reem El Sayed |date=2022-08-01 |title=Mood regulation, alexithymia, and personality disorders in female patients with opioid use disorders |url=https://doi.org/10.1186/s43045-022-00222-z |url-status=live |journal=Middle East Current Psychiatry |volume=29 |issue=1 |pages=57 |doi=10.1186/s43045-022-00222-z |issn=2090-5416 |archive-url=https://web.archive.org/web/20220803013746/https://mecp.springeropen.com/track/pdf/10.1186/s43045-022-00222-z.pdf |archive-date=August 3, 2022}}</ref><ref>{{Cite journal |last=Armstrong |first=Ralph H. |date=2002-06-17 |title=Schizoid Phenomena in Substance Abusers |url=https://doi.org/10.1300/J069v21n03_06 |journal=Journal of Addictive Diseases |volume=21 |issue=3 |pages=73–85 |doi=10.1300/J069v21n03_06 |issn=1055-0887 |pmid=12095001}}</ref> People with SzPD may desire psychedelic drugs more than other kinds.<ref>{{Cite book |last=Ekleberry |first=Sharon C. |url=https://books.google.com/books?id=3gbGBQAAQBAJ&newbks=0&hl=en |title=Integrated Treatment for Co-Occurring Disorders: Personality Disorders and Addiction |date=2011-04-27 |publisher=Routledge |isbn=978-1-136-91493-5 |language=en}}</ref>

=== Secret Schizoids ===
Many schizoid individuals display an engaging, interactive personality, contradicting the observable characteristic emphasized by the [[DSM-5]] and [[ICD-10]] definitions of the schizoid personality. Guntrip (using ideas of Klein, Fairbairn, and Winnicott) classifies these individuals as "secret schizoids", who behave with socially available, interested, engaged, and involved interaction yet remain emotionally withdrawn and sequestered within the safety of the internal world.<ref name="Klein62">{{cite book |author1=Masterson |first=James |url=https://books.google.com/books?id=PytkjA3HNqQC |title=Disorders of the Self – The Masterson Approach |author2=Klein |first2=Ralph |publisher=[[Taylor & Francis]] |isbn=978-087-630-786-1 |location=New York |publication-date=June 17, 2013 |pages=25–27; pp. 54–55; pp. 95–143 (therapy) |language=en |lccn=95020920 |ol=788549M |author-link=James F. Masterson |archive-url=https://openlibrary.org/works/OL18916879W/Disorders_of_the_self?edition=ia%3Adisordersofselfn0000unse |archive-date=February 18, 2022 |url-status=live}}</ref><ref name="Falk2008">{{cite book |author=Avner Falk |url=https://books.google.com/books?id=tcTpj4MMqxIC&pg=PA98 |title=Islamic Terror: Conscious and Unconscious Motives |publisher=ABC-CLIO |year=2008 |isbn=978-0-313-35764-0 |pages=98}}</ref> Klein distinguishes between a "classic" SzPD and a "secret" SzPD, which occur "just as often" as each other. Klein cautions one should not misidentify the schizoid person as a result of the patient's defensive, compensatory interaction with the external world. He suggests one ask the person what their subjective experience is, to detect the presence of the schizoid refusal of emotional intimacy and preference for objective fact.<ref name="Klein62" /> A 2013 study looking at personality disorders and Internet use found that being online more hours per day predicted signs of SzPD. Additionally, SzPD correlated with lower phone call use and fewer Facebook friends.<ref>{{Cite journal |last1=Rosen |first1=L. D. |last2=Whaling |first2=K. |last3=Rab |first3=S. |last4=Carrier |first4=L. M. |last5=Cheever |first5=N. A. |year=2013 |title=Is Facebook creating "iDisorders"? The link between clinical symptoms of psychiatric disorders and technology use, attitudes and anxiety |journal=Computers in Human Behavior |volume=29 |issue=3 |pages=1243–1254 |doi=10.1016/j.chb.2012.11.012 |issn=0747-5632}}</ref>

Descriptions of the schizoid personality as "hidden" behind an outward appearance of emotional engagement have been recognized since 1940, with Fairbairn's description of "schizoid exhibitionism", in which the schizoid individual can express a great deal of feeling and make what appear to be impressive social contacts yet, in reality, gives nothing and loses nothing. Because they are "playing a part", their personality is not involved. According to Fairbairn, ''the person'' disowns the part they are playing, and the schizoid individual seeks to preserve their personality intact and immune from compromise.<ref>{{cite book |author=W. R. D. Fairbairn |url=https://books.google.com/books?id=LwxoUHnyvj0C |title=Psychoanalytic Studies of the Personality |date=2013 |publisher=Routledge |isbn=978-1-134-84213-1 |pages=3–17 |author-link=Ronald Fairbairn}}</ref> The schizoid's false persona is based on what those around them define as normal or good behavior, as a form of compliance.<ref name=":18" /> Further references to the secret schizoid come from [[Masud Khan]],<ref name=":110">{{Cite book |author=Masud Khan |title=The Privacy of the Self – Papers on Psychoanalytic Theory and Technique |publisher=International Universities Press |year=1974 |isbn=978-0823643103 |location=New York |page=70 |chapter=The Role of phobic and counter-phobic mechanisms and separation anxiety in schizoid character formation |author-link=Masud Khan}}</ref> Jeffrey Seinfeld,<ref name=":23">{{cite book |author=Jeffrey Seinfeld |url=https://books.google.com/books?id=r9ZrAAAAMAAJ |title=The Empty Core: An Object Relations Approach to Psychotherapy of the Schizoid Personality |publisher=J. Aronson |year=1991 |isbn=978-0-87668-611-9 |quote=Seinfeld writes: "The schizoid may also seem to be sociable and involved in relationships. However, he is frequently playing a role and not 'fully' involved, unconsciously disowning this role..."}}</ref> and Philip Manfield.<ref name=":5" /> These scholars described secret schizoids as people who enjoy public speaking engagements but experience great difficulty during the breaks when audience members would attempt to engage them emotionally. These references expose the problems in relying on outer observable behavior for assessing the presence of personality disorders in certain individuals.

=== Comorbid Disorders ===

* [[Agoraphobia]]<ref>{{Cite journal |last=Koch |first=Jessa |last2=Modesitt |first2=Taylor |last3=Palmer |first3=Melissa |last4=Ward |first4=Sarah |last5=Martin |first5=Bobbie |last6=Wyatt |first6=Robby |last7=Thomas |first7=Christopher |date=2016 |title=Review of pharmacologic treatment in cluster A personality disorders |url=https://pubmed.ncbi.nlm.nih.gov/29955451/ |url-status=live |journal=The Mental Health Clinician |volume=6 |issue=2 |pages=75–81 |doi=10.9740/mhc.2016.03.75 |issn=2168-9709 |pmc=6007578 |pmid=29955451 |archive-url=https://web.archive.org/web/20220310073801/https://meridian.allenpress.com/mhc/article/6/2/75/127867/Review-of-pharmacologic-treatment-in-cluster-A |archive-date=March 10, 2022}}</ref>
* [[Arthritis]]
* [[Avoidant personality disorder]]<ref name=":1" />
* [[Borderline personality disorder]]<ref name=":1" />
* [[Coronary artery disease]]<ref>{{Cite journal |last=Borroni |first=Serena |last2=Masci |first2=Elisabetta |last3=Franzoni |first3=Chiara |last4=Somma |first4=Antonella |last5=Fossati |first5=Andrea |date=2021-01-01 |title=The Co-Occurrence of Trauma Related Disorder and Borderline Personality Disorder: AQ Study on a Clinical Sample of Patients Seeking Psychotherapy Treatment |url=https://www.sciencedirect.com/science/article/pii/S0165178120332480 |url-status=live |journal=Psychiatry Research |language=en |volume=295 |pages=113587 |doi=10.1016/j.psychres.2020.113587 |issn=0165-1781 |archive-url=https://web.archive.org/web/20220923162546/https://www.sciencedirect.com/science/article/abs/pii/S0165178120332480 |archive-date=September 23, 2022}}</ref>
* [[Complex post-traumatic stress disorder]]
* [[Dysthymia]]
* [[Generalized anxiety disorder]]
* [[Major depressive disorder]]<ref name=":1" />
* [[Panic disorder]]
* [[Paranoid personality disorder]]<ref name=":1" />
* [[Obesity]]
* [[Social anxiety disorder]]
* [[Schizotypal personality disorder]]<ref name=":1" /><ref>{{Cite journal |last=Raine |first=Adrian |date=2006-04-01 |title=Schizotypal Personality: Neurodevelopmental and Psychosocial Trajectories |url=https://www.annualreviews.org/doi/10.1146/annurev.clinpsy.2.022305.095318 |journal=Annual Review of Clinical Psychology |language=en |volume=2 |issue=1 |pages=291–326 |doi=10.1146/annurev.clinpsy.2.022305.095318 |issn=1548-5943}}</ref>

==== Asperger's Syndrome ====
Several studies have reported an overlap or comorbidity with the [[autism spectrum disorder]] [[Asperger syndrome]].<ref name=":172">{{Cite journal |last1=Lugnegård |first1=Tove |last2=Hallerbäck |first2=Maria Unenge |last3=Gillberg |first3=Christopher |date=May 2012 |title=Personality disorders and autism spectrum disorders: what are the connections? |url=https://www.sciencedirect.com/science/article/abs/pii/S0010440X11001325?via%3Dihub |url-status=live |journal=Comprehensive Psychiatry |volume=53 |issue=4 |pages=333–340 |doi=10.1016/j.comppsych.2011.05.014 |pmid=21821235 |archive-url=https://web.archive.org/web/20220815131056/https://www.sciencedirect.com/science/article/abs/pii/S0010440X11001325?via%3Dihub |archive-date=August 15, 2022 |via=[[Elsevier Science Direct]]}}</ref><ref name=":212">{{Cite journal |last=Cook |first=Michal L. |year=2019 |title=On the Continuity Between Autistic and Schizoid Personality Disorder Trait Burden: A Prospective Study in Adolescence |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6982569/ |url-status=live |journal=The Journal of Nervous and Mental Disease |volume=208 |issue=2 |pages=94–100 |doi=10.1097/NMD.0000000000001105 |pmc=6982569 |pmid=31856140 |archive-url=https://web.archive.org/web/20211127175938mp_/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6982569/pdf/nihms-1533812.pdf |archive-date=November 27, 2021 |via=[[PubMed]]}}</ref><ref name=":162" /><ref name=":222">{{Cite journal |last1=Hummelen |first1=Benjamin |last2=Pedersen |first2=Geir |last3=Wilberg |first3=Theresa |last4=Karterud |first4=Sigmund |date=June 2015 |title=Poor Validity of the ''DSM-IV'' Schizoid Personality Disorder Construct as a Diagnostic Category |url=http://dx.doi.org/10.1521/pedi_2014_28_159 |journal=Journal of Personality Disorders |volume=29 |issue=3 |pages=334–346 |doi=10.1521/pedi_2014_28_159 |issn=0885-579X |pmid=25248009}}</ref><ref>{{Cite journal |last=Gadow |first=Kenneth D. |date=2013-04-01 |title=Association of schizophrenia spectrum and autism spectrum disorder (ASD) symptoms in children with ASD and clinic controls |url=https://www.sciencedirect.com/science/article/pii/S0891422213000139 |journal=Research in Developmental Disabilities |language=en |volume=34 |issue=4 |pages=1289–1299 |doi=10.1016/j.ridd.2013.01.011 |issn=0891-4222}}</ref><ref>{{Cite journal |last=Wolff |first=Sula |date=1991 |title=‘Schizoid’ Personality in Childhood and Adult Life III: The Childhood Picture |url=https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/abs/schizoid-personality-in-childhood-and-adult-life-iii-the-childhood-picture/1EA3B194FADC3226A671286BA57A98F1 |url-status=live |journal=The British Journal of Psychiatry |language=en |volume=159 |issue=5 |pages=629–635 |doi=10.1192/bjp.159.5.629 |issn=0007-1250 |pmid=1756338 |archive-url=https://web.archive.org/web/20210525181644/https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/abs/schizoid-personality-in-childhood-and-adult-life-iii-the-childhood-picture/1EA3B194FADC3226A671286BA57A98F1 |archive-date=May 25, 2021}}</ref> Asperger syndrome had traditionally been called "[[schizoid disorder of childhood]]",<ref>{{Cite journal |last=Wolff |first=S. |last2=Barlow |first2=A. |date=1979 |title=Schizoid personality in childhood: a comparative study of schizoid, autistic and normal children |url=https://pubmed.ncbi.nlm.nih.gov/422686/ |journal=Journal of Child Psychology and Psychiatry, and Allied Disciplines |volume=20 |issue=1 |pages=29–46 |doi=10.1111/j.1469-7610.1979.tb01704.x |issn=0021-9630 |pmid=422686 |via=[[PubMed]]}}</ref><ref>{{Cite book |last=Wolff |first=Sula |url=http://ndl.ethernet.edu.et/bitstream/123456789/76260/1/25.pdf |title=Schizoid Personality in Childhood and Asperger Syndrome |work=Asperger Syndrome |publisher=[[The Guilford Press]] |isbn=978-157-230-534-2 |editor-last=Klin |editor-first=Ami |edition=1st |location=[[New York]] |publication-date=February 18, 2020 |pages=278-309 |language=en |editor-last2=Volkmar |editor-first2=Frederick |editor-last3=Sparrow |editor-first3=Sara |archive-url=https://web.archive.org/web/20210806170142/http://ndl.ethernet.edu.et/bitstream/123456789/76260/1/25.pdf |archive-date=August 6, 2021 |url-status=live}}</ref><ref>{{Cite journal |last=Wolff |first=Sula |author-link=Sula Wolff |title=The history of autism |url=https://link.springer.com/article/10.1007/s00787-004-0363-5 |url-status=live |journal=European Child & Adolescent Psychiatry |publisher=[[Springer Publishing]] |publication-date=August 19, 2004 |volume=13 |page=204 |doi=10.1007/s00787-004-0363-5 |archive-url=https://web.archive.org/web/20220926224443/https://link.springer.com/article/10.1007/s00787-004-0363-5 |archive-date=September 26, 2022 |via=[[SpringerLink]]}}</ref> and [[Eugen Bleuler]] coined both the terms "autism" and "schizoid" to describe withdrawal to an internal fantasy, against which any influence from outside becomes an intolerable disturbance.<ref>{{cite journal |vauthors=Kuhn R |year=2004 |title=Eugen Bleuler's concepts of psychopathology |journal=Hist Psychiatry |volume=15 |issue=3 |pages=361–366 |doi=10.1177/0957154X04044603 |pmid=15386868 |s2cid=5317716}} The quote is a translation of Bleuler's 1910 original.</ref> In a 2012 study of a sample of 54 young adults with Asperger syndrome, it was found that 26% of them also met the criteria for SzPD, the highest comorbidity out of any personality disorder in the sample (the other comorbidities were 19% for [[obsessive–compulsive personality disorder]], 13% for [[avoidant personality disorder]] and one female with [[schizotypal personality disorder]]). Additionally, twice as many men with Asperger syndrome met the criteria for SzPD than women. While 41% of the whole sample were unemployed with no occupation, this rose to 62% for the Asperger's and SzPD comorbid group.<ref name=":172" /> [[Digby Tantam|Tantam]] suggested that Asperger syndrome may confer an increased risk of developing SzPD.<ref name=":162" /> A 2019 study found that 54% of a group of males aged 11 to 25 with Asperger syndrome showed significant SzPD traits, with 6% meeting full diagnostic criteria for SzPD, compared to 0% of a control group.<ref name=":212" />

In the 2012 study, it was noted that the [[Diagnostic and Statistical Manual of Mental Disorders|DSM]] may complicate diagnosis by requiring the exclusion of a [[pervasive developmental disorder]] (PDD) before establishing a diagnosis of SzPD. The study found that social interaction impairments, stereotyped behaviors, and specific interests were more severe in the individuals with Asperger syndrome also fulfilling SzPD criteria, against the notion that social interaction skills are unimpaired in SzPD. The authors believe that a substantial subgroup of people with autism spectrum disorder or PDD have clear "schizoid traits" and correspond largely to the "loners" in [[Lorna Wing]]'s classification ''The autism spectrum'' ([[The Lancet|Lancet]] 1997), described by [[Sula Wolff]].<ref name=":172" /> The authors of the 2019 study hypothesized that it is extremely likely that historic cohorts of adults diagnosed with SzPD either also had childhood-onset autistic syndromes or were misdiagnosed. They stressed that further research to clarify overlap and distinctions between these two syndromes was strongly warranted, especially given that high-functioning autism spectrum disorders are now recognized in around 1% of the population.<ref name=":19">{{Cite web |last=Cook |first=Michal |date=2019-05-03 |title=Pronounced Overlap of Autistic and Schizoid Personality Trait Burden in Adolescence |url=https://insar.confex.com/insar/2019/webprogram/Paper30221.html |url-status=live |archive-url=https://web.archive.org/web/20210308124022/https://insar.confex.com/insar/2019/webprogram/Paper30221.html |archive-date=March 8, 2021 |website=IMFAR |language=en}}</ref>

== Treatment ==

=== Medication ===
There are no effective [[Psychiatric medication|medications]] for Schizoid Personality Disorder. However, certain medications may reduce the symptoms of SzPD as well as treat co-occurring [[mental disorders]]. Since the symptoms of SzPD mirror the negative symptoms of schizophrenia, [[Antipsychotic|antipsychotics]] have been suggested as a potentially effective medication for SzPD.<ref name=":282">{{Cite web |date=August 17, 2017 |title=Schizoid personality disorder - Diagnosis and treatment - Mayo Clinic |url=https://www.mayoclinic.org/diseases-conditions/schizoid-personality-disorder/diagnosis-treatment/drc-20354419 |url-status=live |archive-url=https://web.archive.org/web/20220607183034/https://www.mayoclinic.org/diseases-conditions/schizoid-personality-disorder/diagnosis-treatment/drc-20354419 |archive-date=June 7, 2022 |access-date=2022-09-30 |website=www.mayoclinic.org |language=en}}</ref><ref name=":7" /><ref>{{Cite journal |last=Di Lorenzo |first=Rosaria |last2=Tondelli |first2=Grazia |last3=Genedani |first3=Susanna |date=June 1, 2001 |title=Effectiveness of clozapine and olanzapine: a comparison in severe, psychotically ill patients |url=https://academic.oup.com/crawlprevention/governor?content=%2fijnp%2farticle%2f4%2f2%2f135%2f794934 |url-status=live |journal=[[International Journal of Neuropsychopharmacology]] |volume=4 |issue=2 |doi=10.1017/S1461145701002309 |archive-url=https://web.archive.org/web/20180610090111/https://academic.oup.com/ijnp/article/4/2/135/794934 |archive-date=June 10, 2018 |access-date=2022-09-28 |via=[[Oxford Academic]]}}</ref><ref>{{Cite journal |last=Di Lorenzo |first=Rosaria |last2=Amoretti |first2=Alessandra |last3=Forghieri |first3=Matilde |last4=Fiorini |first4=Fiorenza |last5=Genedani |first5=Susanna |last6=Rigatelli |first6=Marco |date=2007 |title=Aripiprazole: effectiveness and safety under naturalistic conditions |url=https://pubmed.ncbi.nlm.nih.gov/18179310/ |journal=Experimental and Clinical Psychopharmacology |volume=15 |issue=6 |pages=569–575 |doi=10.1037/1064-1297.15.6.569 |issn=1064-1297 |pmid=18179310 |via=[[PubMed]]}}</ref> Originally, low doses of [[atypical antipsychotics]] like [[risperidone]] or [[olanzapine]] were used to alleviate social deficits and blunted affect.<ref>{{Cite book |url=https://link.springer.com/book/10.1007/978-1-4757-6876-3 |title=Treatment of Personality Disorders |publisher=[[Springer Science+Business Media|Springer]] |language=en |doi=10.1007/978-1-4757-6876-3 |url-status=live}}</ref><ref>{{Citation |last=Lee |first=Royce |title=The Psychopharmacological Treatment of Personality Disorders |date=2002-07-30 |url=https://onlinelibrary.wiley.com/doi/10.1002/0470854871.chxxvi9 |work=Biological Psychiatry |pages=1419–1429 |editor-last=D'Haenen |editor-first=Hugo |place=Chichester, UK |publisher=John Wiley & Sons, Ltd |language=en |doi=10.1002/0470854871.chxxvi9 |isbn=978-0-471-49198-9 |access-date=2022-10-02 |last2=Coccaro |first2=Emil |editor2-last=den Boer |editor2-first=J. A. |editor3-last=Willner |editor3-first=P.}}</ref><ref name="SonnyJoseph2">{{Cite book |last=Sonny |first=Joseph |url=https://www.google.com/books/edition/Personality_Disorders/KEoPC3_1AGAC?hl=en&gbpv |title=Personality Disorders: New Symptom-Focused Drug Therapy |publisher=Psychology Press |year=1997 |isbn=9780789001344 |pages=45–56 |language=en |chapter=Chapter 3, Schizoid Personality Disorder |chapter-url=https://books.google.com/books?id=KEoPC3_1AGAC&pg=PA45}}</ref><ref>{{Cite journal |last=Newton-Howes |first=Giles |last2=Tyrer |first2=Peter |date=2003-10-01 |title=Pharmacotherapy for personality disorders |url=https://doi.org/10.1517/14656566.4.10.1643 |journal=Expert Opinion on Pharmacotherapy |volume=4 |issue=10 |pages=1643–1649 |doi=10.1517/14656566.4.10.1643 |issn=1465-6566 |pmid=14521475}}</ref> However, a 2012 review concluded that atypical antipsychotics were ineffective for treating personality disorders.<ref name=":152" /> [[Antidepressant|Antidepressants]],<ref name=":4" /> [[Selective serotonin reuptake inhibitor|SSRIs]],<ref>{{Cite book |url=https://link.springer.com/book/10.1007/978-3-7091-1501-5 |title=Psychiatric Drugs in Children and Adolescents |pages=477-478 |language=en |doi=10.1007/978-3-7091-1501-5 |via=[[SpringerLink]]}}</ref> [[Anxiolytic|anxiolitics]],<ref name=":18" /> [[bupropion]],<ref name="SonnyJoseph2" /> [[modafinil]],<ref>{{Cite journal |last=Scoriels |first=Linda |year=2013 |title=Modafinil effects on cognition and emotion in schizophrenia and its neurochemical modulation in the brain |url=https://www.researchgate.net/publication/229436574 |journal=Neuropharmacology |volume=64 |pages=168–184 |doi=10.1016/j.neuropharm.2012.07.011 |pmid=22820555 |s2cid=17975469}}</ref> [[Benzodiazepine|benzodiazepines]],<ref>{{Citation |last=Cloninger |first=C. Robert |title=Personality Disorders |date=2008 |url=https://doi.org/10.1007/978-1-59745-252-6_28 |work=The Medical Basis of Psychiatry |page=480 |pages=471–483 |editor-last=Fatemi |editor-first=S. Hossein |place=Totowa, NJ |publisher=Humana Press |language=en |doi=10.1007/978-1-59745-252-6_28 |isbn=978-1-59745-252-6 |access-date=2022-10-04 |last2=Svrakic |first2=Dragan M. |editor2-last=Clayton |editor2-first=Paula J. |via=[[SpringerLink]]}}</ref><ref>{{Cite journal |last=Simoni-Wastila |first=Linda |last2=Ross-Degnan |first2=Dennis |last3=Mah |first3=Connie |last4=Gao |first4=Xiaoming |last5=Brown |first5=Jeffrey |last6=Cosler |first6=Leon E. |last7=Fanning |first7=Thomas |last8=Gallagher |first8=Peter |last9=Salzman |first9=Carl |last10=Soumerai |first10=Stephen B. |date=2004-02-01 |title=A retrospective data analysis of the impact of the New York triplicate prescription program on benzodiazepine use in medicaid patients with chronic psychiatric and neurologic disorders |url=https://www.sciencedirect.com/science/article/pii/S0149291804900306 |url-status=live |journal=Clinical Therapeutics |language=en |volume=26 |issue=2 |pages=322–336 |doi=10.1016/S0149-2918(04)90030-6 |issn=0149-2918}}</ref> [[electrocardiography]], and [[biofeedback]] may also be effective treatments.<ref>{{Cite journal |last=Sumpf |first=Maria |last2=Jentschke |first2=Sebastian |last3=Koelsch |first3=Stefan |date=2015-06-17 |title=Effects of Aesthetic Chills on a Cardiac Signature of Emotionality |url=https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0130117 |url-status=live |journal=PLOS ONE |language=en |volume=10 |issue=6 |pages=e0130117 |doi=10.1371/journal.pone.0130117 |issn=1932-6203 |pmc=PMC4470584 |pmid=26083383 |archive-url=https://web.archive.org/web/20220617114616/https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0130117 |archive-date=June 17, 2022}}</ref>
[[File:Cognitive_behavioral_therapy_-_basic_tenets.svg|thumb|203x203px|Basic tenets of [[Cognitive behavioral therapy|Cognitive-Behavioral Therapy]], a kind of Psychotherapy used to treat SzPD]]

=== Psychotherapy ===
Treatment for this disorder uses a combination of [[Cognitive behavioral therapy|Cognitive-behavioral therapy]] and [[Psychodynamic psychotherapy]].<ref name=":4" /><ref>{{Cite journal |last=Devany |first=Karina |last2=Poerwandari |first2=Elizabeth Kristi |date=2020-09-08 |title=Integrating cognitive-behavioral therapy and gratitude therapy for treating somatic symptom disorder with schizoid-avoidant personality features: A case report |url=https://publication.k-pin.org/index.php/jpu/article/view/127 |url-status=live |journal=Jurnal Psikologi Ulayat: Indonesian Journal of Indigenous Psychology |language=en |volume=7 |issue=2 |pages=113–121 |doi=10.24854/jpu127 |issn=2580-1228 |archive-url=https://web.archive.org/web/20210513180808/https://publication.k-pin.org/index.php/jpu/article/view/127 |archive-date=May 31, 2021}}</ref><ref>{{Cite journal |last=Osma |first=Jorge |last2=Sánchez-Gómez |first2=Arantxa |last3=Peris-Baquero |first3=Óscar |date=2018 |title=Applying the unified protocol to a single case of major depression with schizoid and depressive personality traits |url=https://pubmed.ncbi.nlm.nih.gov/30353835/ |url-status=live |journal=Psicothema |volume=30 |issue=4 |pages=364–369 |doi=10.7334/psicothema2018.41 |issn=1886-144X |pmid=30353835 |archive-url=https://web.archive.org/web/20220126192123/https://www.psicothema.com/pdf/4494.pdf |archive-date=January 26, 2022}}</ref> These techniques can be used to help the patient identify their [[Defence mechanism|defense mechanisms]] and change them.<ref name=":92" /><ref>{{Cite journal |last=Mankiewicz |first=Pawel |last2=Renton |first2=Julia |date=November 29, 2017 |title=Increasing Psychosocial Health with Cognitive Therapy in Schizoid Personality Disorder: A Single Subject Design |url=https://www.athensjournals.gr/health/2019-6-4-1-Mankiewicz.pdf |url-status=live |journal=Athens Journal of Health & Medical Sciences |language=english |volume=6 |issue=4 |pages=197-212 |doi=10.30958/ajhms.6-4-1 |archive-url=https://web.archive.org/web/20190803001211/https://www.athensjournals.gr/reviews/2019-3127-AJHMS-PDF.pdf |archive-date=August 3, 2019 |via=[[Semantic Scholar]]}}</ref><ref>{{Cite journal |last=Haimowitz |first=Carla |date=2000-01-01 |title=Maybe It's Not “Kick Me” After All: Transactional Analysis and Schizoid Personality Disorder |url=https://doi.org/10.1177/036215370003000109 |journal=Transactional Analysis Journal |volume=30 |issue=1 |pages=84–90 |doi=10.1177/036215370003000109 |issn=0362-1537}}</ref> Therapists also attempt to establish a healthy relationship with the client with SzPD.<ref>{{Cite journal |last=Ward |first=Randy K. |date=2004-10-15 |title=Assessment and management of personality disorders |url=https://www.aafp.org/dam/brand/aafp/pubs/afp/issues/2004/1015/p1505.pdf |url-status=live |journal=American Family Physician |volume=70 |issue=8 |pages=1505–1512 |issn=0002-838X |pmid=15526737 |archive-url=https://web.archive.org/web/20220927212841/https://www.aafp.org/pubs/afp/issues/2004/1015/p1505.html |archive-date=September 27, 2022}}</ref> This can help combat their internalized belief that relationships are harmful and unhelpful. Relationships with a therapist can seem terrifying and intrusive to a person with SzPD.<ref>{{Cite journal |last=Roberts |first=Donald |title=Differential interventions in psychotherapy of borderline, narcissistic, and schizoid personality disorders: the Masterson approach |url=https://onlinelibrary.wiley.com/doi/abs/10.1002/%28SICI%291099-0879%28199712%294%3A4%3C233%3A%3AAID-CPP141%3E3.0.CO%3B2-F |journal=Clinical Psychology and Psychotherapy |publication-date=January 5, 1999 |volume=4 |issue=4 |doi=10.1002/(SICI)1099-0879(199712)4:4<233::AID-CPP141>3.0.CO;2-F |via=[[Wiley Online Library]]}}</ref><ref>{{Cite journal |last=Coen |first=Stanley J. |date=2005 |title=How to play with patients who would rather remain remote |url=https://pubmed.ncbi.nlm.nih.gov/16187635/ |url-status=live |journal=Journal of the American Psychoanalytic Association |volume=53 |issue=3 |pages=813-814 |doi=10.1177/00030651050530030601 |issn=0003-0651 |pmid=16187635}}</ref> They may feel as if they need to alter or hide their feelings to meet the therapist's demands or expectations. To combat this, therapists try to gradually increase their patient's emotional expression. Expressing too much too early can lead to them ending therapy. Treatment for a person with SzPD must be [[Person-centered therapy|person-centered]], with the client feeling understood and well-regarded.<ref name=":8" /><ref>{{Cite journal |last=Little |first=Ray |date=2001-01-01 |title=Schizoid Processes: Working with the Defenses of the Withdrawn Child Ego State |url=https://doi.org/10.1177/036215370103100105 |journal=Transactional Analysis Journal |volume=31 |issue=1 |pages=33–43 |doi=10.1177/036215370103100105 |issn=0362-1537}}</ref><ref>{{Cite journal |last=Erskine |first=Richard G. |date=2020-12-23 |title=Relational Withdrawal, Attunement to Silence: Psychotherapy of the Schizoid Process |url=https://www.integrative-journal.com/index.php/ijip/article/view/161 |url-status=live |journal=International Journal of Integrative Psychotherapy |language=en |volume=11 |issue=1 |pages=14–28 |issn=2156-9703 |archive-url=https://web.archive.org/web/20220122195257/https://www.integrative-journal.com/index.php/ijip/article/view/161/0 |archive-date=January 22, 2022}}</ref> This can allow the patient to connect with and understand their emotions.<ref>{{Cite journal |last=Kramer |first=U. |last2=Meystre |first2=C. |date=2010-05-26 |title=Assimilation process in a psychotherapy with a client presenting schizoid personality disorder |url=https://sanp.ch/article/doi/sanp.2010.02162 |url-status=live |journal=Swiss Archives of Neurology, Psychiatry and Psychotherapy |language=en |issue=4 |doi=10.4414/sanp.2010.02162 |archive-url=https://web.archive.org/web/20200212092812/https://sanp.ch/journalfile/view/article/ezm_sanp/en/sanp.2010.02162/beb300bdc6eacd71aaf75d332edb654438bd44db/sanp_2010_02162.pdf/rsrc/jf |archive-date=February 12, 2020}}</ref><ref>{{Cite journal |last=New |first=Antonia S. |date=2012 |title=Commentary on ‘Schizoid personality disorder-the peculiarities of their interpersonal relationships and existential roles’ by Nirestean, et al.: Commentary |url=https://onlinelibrary.wiley.com/doi/10.1002/pmh.1180 |journal=Personality and Mental Health |language=en |volume=6 |issue=1 |pages=83–85 |doi=10.1002/pmh.1180}}</ref><ref>{{Cite journal |last=Orcutt |first=Candace |date=2018 |title=Schizoid Fantasy: Refuge or Transitional Location? |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5840255/ |url-status=live |journal=Clinical Social Work Journal |volume=46 |issue=1 |pages=42–47 |doi=10.1007/s10615-017-0629-2 |issn=0091-1674 |pmc=5840255 |pmid=29540940 |archive-url=https://web.archive.org/web/20201109031604/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5840255/ |archive-date=November 9, 2020}}</ref> If a person with SzPD does not have their feelings validated or has their emotions confronted, this will confirm their belief that expressing themselves is dangerous.<ref name=":18" /> Therapists also attempt to avoid intruding on the patient with SzPD's life or restricting their freedoms,<ref name=":18" /> as this can make the patient feel as if therapy is intolerable.<ref name=":12" /> Because of this, therapy for people with SzPD is usually less structured then treatment programs for other disorders.<ref name=":18" />Patients with SzPD may benefit from long-term treatment lasting several years.<ref>{{Cite journal |last=Joseph |first=Lawrence |last2=Anderson |first2=Eric |last3=Kristine |first3=Amy |last4=Streich |first4=Fatzer |year=2004 |title=Assessing Progress in Analysis Interminable |url=https://journals.sagepub.com/doi/10.1177/00030651040520041301 |url-status=live |journal=[[Journal of the American Psychoanalytic Association]] |language=en |volume=52 |issue=4 |doi=10.1177/00030651040520041301 |via=SAGE publishing}}</ref><ref name=":152" /> [[Inpatient care]] may also be an effective way of treating SzPD and other Cluster A disorders.<ref>{{Cite journal |last=Bartak |first=Anna |last2=Andrea |first2=Helene |last3=Spreeuwenberg |first3=Marieke D. |last4=Thunnissen |first4=Moniek |last5=Ziegler |first5=Uli M. |last6=Dekker |first6=Jack |last7=Bouvy |first7=Fleur |last8=Hamers |first8=Elisabeth F. M. |last9=Meerman |first9=Anke M. M. A. |last10=Busschbach |first10=Jan J. V. |last11=Verheul |first11=Roel |last12=Stijnen |first12=Theo |last13=Emmelkamp |first13=Paul M. G. |date=2011 |title=Patients with Cluster A Personality Disorders in Psychotherapy: An Effectiveness Study |url=https://www.karger.com/Article/FullText/320587 |url-status=live |journal=Psychotherapy and Psychosomatics |language=english |volume=80 |issue=2 |pages=88–99 |doi=10.1159/000320587 |issn=0033-3190 |pmid=21196806 |archive-url=https://web.archive.org/web/20220809072729/https://www.karger.com/Article/Abstract/320587 |archive-date=August 9, 2022}}</ref>

== Controversy ==
The original concept of the schizoid character developed by [[Ernst Kretschmer]] in the 1920s comprised an amalgamation of [[Avoidant personality disorder|avoidant]], [[Schizotypal personality disorder|schizotypal]], and schizoid traits. It was not until 1980 and the work of [[Theodore Millon]] that led to splitting this concept into three personality disorders (now schizoid, schizotypal, and avoidant). This caused debate about whether this was accurate or if these traits were different expressions of a single personality disorder.<ref name=":132" /> It has also been argued due to the poor consistency and efficiency of diagnosis due to overlapping traits that SzPD should be removed altogether from the DSM.<ref name=":222" />

A 2012 article suggested that two different disorders may better represent SzPD: one affect-constricted disorder (belonging to schizotypal PD) and a seclusive disorder (belonging to avoidant PD). They called for the replacement of the SzPD category from future editions of the DSM with a dimensional model which would allow for the description of schizoid traits on an individual basis.<ref name=":102" />

Some critics such as [[Nancy McWilliams]] of [[Rutgers University]] and Parpottas Panagiotis of [[European University Cyprus]] argue that the definition of SzPD is flawed due to [[cultural bias]] and that it does not constitute a mental disorder but simply an [[Attachment in adults#Dismissive%E2%80%93avoidant|avoidant attachment style]] requiring a more distant emotional proximity.<ref name=":8" /><ref>{{cite book |last=Nancy McWilliams |url=https://books.google.com/books?id=BzPOAWB2DncC&pg=PA196 |title=Psychoanalytic Diagnosis: Understanding Personality Structure in the Clinical Process |date=2011 |publisher=[[Guilford Press]] |isbn=9781609184940 |edition=2nd |location=New York |page=196 |author-link=Nancy McWilliams}}</ref> If that is true, then many of the more problematic reactions these individuals show in social situations may be partly accounted for by the judgments commonly imposed on people with this style. However, impairment is mandatory for any behavior to be [[Personality disorder#DSM-5 general criteria|diagnosed as a personality disorder]]. SzPD seems to satisfy this criterion because it is linked to negative outcomes. These include a significantly compromised [[quality of life]], reduced [[Global Assessment of Functioning|overall functioning]] even after 15 years, and one of the lowest levels of "life success" of all personality disorders (measured as "status, wealth and successful relationships").<ref name=":102" /><ref name=":92" /><ref name=":1222">{{Cite journal |last=Skodol |first=Andrew E. |author1-link=Andrew E. Skodol |year=2011 |title=Personality Disorder Types Proposed for DSM-5 |url=https://www.researchgate.net/publication/51019147 |url-status=live |journal=Journal of Personality Disorders |volume=25 |issue=2 |pages=136–69 |doi=10.1521/pedi.2011.25.2.136 |pmid=21466247 |archive-url=https://web.archive.org/web/20210829050156/https://www.researchgate.net/publication/51019147_Personality_Disorder_Types_Proposed_for_DSM-5 |archive-date=August 29, 2021 |via=[[ResearchGate]]}}</ref> However, the determination of what qualifies as "impairments" or as "negative outcomes" is itself potentially subject to cultural bias. People with SzPD may not regard a lack of social status or successful relationships, for example, as harm. Furthermore, correlation with negative outcomes does not necessarily demonstrate that these outcomes were directly caused by schizoid traits. Rather, it may be that these outcomes are the result of discrimination against people with SzPD, who may be viewed as abnormal.

== Diagnosis ==

=== Guntrip criteria ===
Ralph Klein, Clinical Director of the [[James F. Masterson|Masterson]] Institute, delineates the following nine characteristics of the schizoid personality as described by [[Harry Guntrip]]:<ref name=":133">{{Cite web |last=Materson |first=James |author-link=James F. Masterson |last2=Klein |first2=Ralph |date=June 23, 2015 |title=Disorders of the Self: New Therapeutic Horizons: The Masterson Approach |url=https://www.routledge.com/Disorders-of-the-Self-New-Therapeutic-Horizons-The-Masterson-Approach/Masterson-MD-Klein-MD/p/book/9781138883741 |url-status=live |archive-url=https://web.archive.org/web/20220227090417/https://www.routledge.com/Disorders-of-the-Self-New-Therapeutic-Horizons-The-Masterson-Approach/Masterson-MD-Klein-MD/p/book/9781138883741 |archive-date=February 27, 2022 |access-date=2022-09-29 |website=Routledge & CRC Press |language=en |isbn=978-113-888-374-1}}</ref>{{rp|13–23}}

* [[Introversion]]
* [[Solitude|Withdrawnness]]
* [[Narcissism]]
* [[Self-sufficiency]]
* A [[Grandiosity|sense of superiority]]
* [[Reduced affect display|Loss of affect]]
* [[Loneliness]]
* [[Depersonalization]]
* [[Regression (psychology)|Regression]]

The description of Guntrip's nine characteristics should clarify some differences between the traditional DSM portrait of SzPD and the traditional informed [[object relations]] view. All nine characteristics are consistent. Most, if not all, must be present to diagnose a schizoid disorder.<ref name=":133" />

=== Millon's subtypes ===
[[Theodore Millon]] restricted the term "schizoid" to those personalities who lack the capacity to form social relationships. He characterizes their way of thinking as being vague and void of thoughts and as sometimes having a "defective perceptual scanning". Because they often do not perceive cues that trigger [[affective]] responses, they experience fewer emotional reactions.<ref>[[Aaron T. Beck]]; Arthur Freeman (1990). "Chapter 7 Schizoid and Schizotypal PD (p.120-146)". ''Cognitive Therapy of Personality Disorders'' (1st ed.). The Guilford Press. pp. 125 (Millon), 127–129 (cognitive therapy conceptualization). [[ISBN (identifier)|ISBN]] [[Special:BookSources/9780898624342|<bdi>9780898624342</bdi>]]. [[OCLC (identifier)|OCLC]] 906420553.</ref><ref>{{Cite book |last1=DiGiuseppe |first1=Raymond |url=https://books.google.com/books?id=kYsRDAAAQBAJ&q=schizoid+%22perceptual+scanning%22&pg=PA207 |title=Understanding Anger Disorders |last2=Tafrate |first2=Raymond Chip |date=2007 |publisher=Oxford University Press, USA |isbn=9780195170795 |pages=207 |language=en}}</ref>

For Millon, SzPD is distinguished from other personality disorders in that it is "the personality disorder that lacks a personality." He criticizes that this may be due to the current diagnostic criteria: They describe SzPD only by an absence of certain traits, which results in a "deficit syndrome" or "vacuum". Instead of delineating the presence of something, they mention solely what is lacking. Therefore, it is hard to describe and research such a concept.<ref name=":163">{{Cite book |last=Millon |first=Theodore |url=http://archive.org/details/personalitydisor00mill |title=Personality Disorders in Modern Life. [electronic resource] |last2=Millon |first2=Carrie M. |last3=Meagher |first3=Sarah |publisher=Hoboken : John Wiley & Sons |others=Library Genesis |isbn=978-0-471-66850-3 |publication-date=November 8, 2004}}</ref>

He identified four subtypes of SzPD. Any individual schizoid may exhibit none or one of the following:<ref name=":163" /><ref>{{Cite web |title=Millon Theory - Retiring/Schizoid Personality |url=https://www.millonpersonality.com/theory/diagnostic-taxonomy/schizoid.htm |url-status=live |archive-url=https://web.archive.org/web/20211102134147/https://www.millonpersonality.com/theory/diagnostic-taxonomy/schizoid.htm |archive-date=November 2, 2021 |access-date=2022-09-29 |website=www.millonpersonality.com}}</ref>
{| class="wikitable"
{| class="wikitable"
!Subtype
|+Clinical features of schizoid personality disorder<ref name="Akhtar" />
!Features
! rowspan="2" | Area
|-
|-
|'''Languid schizoid''' (including [[Dependent personality disorder|dependent]] and [[Depressive personality disorder|depressive]] features)
|Marked inertia; deficient activation level; intrinsically phlegmatic, lethargic, weary, leaden, lackadaisical, exhausted, enfeebled. Unable to act with spontaneity or seeks simplest pleasures, may experience profound angst, yet lack the vitality to express it strongly.
|-
|'''Remote schizoid''' (including [[Avoidant personality disorder|avoidant]] features)
|Distant and removed; inaccessible, solitary, isolated, homeless, disconnected, secluded, aimlessly drifting; peripherally occupied. Seen among people who would have been otherwise capable of developing normal emotional life but having been subjected to intense hostility lost their innate capability to form bonds. Some residual anxiety is present.
|-
|'''Depersonalized schizoid''' (including [[Schizotypal personality disorder|schizotypal]] features)
|Disengaged from others and self; self is disembodied or distant object; body and mind sundered, cleaved, dissociated, disjoined, eliminated. Often seen as simply staring into the empty space or being occupied with something substantial while actually being occupied with nothing at all.
|-
|'''Affectless schizoid''' (including [[Obsessive-compulsive personality disorder|compulsive]] features)
|Passionless, unresponsive, unaffectionate, chilly, uncaring, unstirred, spiritless, lackluster, unexcitable, unperturbed, cold; all emotions diminished. Combines the preference for rigid schedule (obsessive-compulsive feature) with the coldness of the schizoid.
|}

=== Akhtar's profile ===
American psychoanalyst [[Salman Akhtar]] provided a comprehensive phenomenological profile of SzPD in which classic and contemporary descriptive views are synthesized with psychoanalytic observations. This profile is summarized in the table reproduced below that lists clinical features that involve six areas of psychosocial functioning and are organized by "overt" and "covert" manifestations.

"Overt" and "covert" are intended to denote seemingly contradictory aspects that may both simultaneously be present in an individual.<ref name="Akhtar2">{{cite book |author=Salman Akhtar |url=https://books.google.com/books?id=bU0eAAAAQBAJ&pg=PA121 |title=Schizoid Personality Disorder: A Synthesis of Developmental, Dynamic, and Descriptive Features |journal=American Journal of Psychotherapy |year=1987 |isbn=9781461627685 |volume=41 |pages=499–518 |doi=10.1176/appi.psychotherapy.1987.41.4.499 |pmid=3324773 |access-date=2017-02-10 |archive-url=https://web.archive.org/web/20170731160223/https://books.google.de/books?id=bU0eAAAAQBAJ&pg=PA121 |archive-date=2017-07-31 |url-status=live |issue=4}}</ref> These designations do not necessarily imply their conscious or unconscious existence. The covert characteristics are by definition difficult to discern and not immediately apparent. Additionally, the lack of data on the frequency of many of the features makes their relative diagnostic weight difficult to distinguish at this time. However, Akhtar states that his profile has several advantages over the DSM in terms of maintaining historical continuity of the use of the word ''schizoid'', valuing depth and complexity over descriptive oversimplification and helping provide a more meaningful [[differential diagnosis]] of SzPD from other personality disorders.<ref name="Akhtar2" />
{| class="wikitable"
|+Clinical features of schizoid personality disorder<ref name="Akhtar3">{{cite book |author=Salman Akhtar |url=https://books.google.com/books?id=bU0eAAAAQBAJ&pg=PA121 |title=Schizoid Personality Disorder: A Synthesis of Developmental, Dynamic, and Descriptive Features |journal=American Journal of Psychotherapy |year=1987 |isbn=9781461627685 |volume=41 |pages=499–518 |doi=10.1176/appi.psychotherapy.1987.41.4.499 |pmid=3324773 |access-date=2017-02-10 |archive-url=https://web.archive.org/web/20170731160223/https://books.google.de/books?id=bU0eAAAAQBAJ&pg=PA121 |archive-date=2017-07-31 |url-status=live |issue=4}}</ref>
!Area
!Overt characteristics
!Overt characteristics
!Covert characteristics
!Covert characteristics
Line 86: Line 194:
|[[Self-concept]]
|[[Self-concept]]
|
|
*compliant
* compliant
*stoic
* stoic
*noncompetitive
* noncompetitive
*[[self-sufficient]]
* [[self-sufficient]]
*lacking [[assertiveness]]
* lacking [[assertiveness]]
*feeling [[inferiority complex|inferior]] and an outsider in life
* feeling [[Inferiority complex|inferior]] and an outsider in life
|
|
*[[cynical]]
* [[cynical]]
*[[Authenticity (philosophy)|inauthentic]]
* [[Authenticity (philosophy)|inauthentic]]
*[[depersonalized]]
* [[depersonalized]]
*alternately feeling empty, robot-like and full of [[omnipotent]], [[Revenge|vengeful]] [[Fantasy (psychology)|fantasies]]
* alternately feeling empty, robot-like and full of [[omnipotent]], [[Revenge|vengeful]] [[Fantasy (psychology)|fantasies]]
*hidden [[grandiosity]]
* hidden [[grandiosity]]
|-
|-
|[[Interpersonal relations]]
|[[Interpersonal relations]]
|
|
*[[Social withdrawal|withdrawn]]
* [[Social withdrawal|withdrawn]]
*aloof
* aloof
*have few close friends
* have few close friends
*impervious to others' emotions
* impervious to others' emotions
*afraid of [[intimacy]]
* afraid of [[intimacy]]
|
|
*exquisitely sensitive
* exquisitely sensitive
*deeply curious about others
* deeply curious about others
*hungry for love
* hungry for love
*[[envious]] of others' spontaneity
* [[envious]] of others' spontaneity
*intensely needy of involvement with others
* intensely needy of involvement with others
*capable of [[Stimulation|excitement]] with carefully selected intimates
* capable of [[Stimulation|excitement]] with carefully selected intimates
|-
|-
|[[Socialization|Social adaptation]]
|[[Socialization|Social adaptation]]
|
|
*prefer solitary occupational and [[recreational activities]]
* prefer solitary occupational and [[recreational activities]]
*marginal or [[Eclecticism|eclectically]] sociable in groups
* marginal or [[Eclecticism|eclectically]] sociable in groups
*vulnerable to [[esoteric movement]]s owing to a strong [[need to belong]]
* vulnerable to [[Esoteric movement|esoteric movements]] owing to a strong [[need to belong]]
*tend to be lazy and indolent
* tend to be lazy and indolent
|
|
*lack clarity of goals
* lack clarity of goals
*weak [[ethnic]] affiliation
* weak [[ethnic]] affiliation
*usually capable of steady work
* usually capable of steady work
*quite creative and may make unique and original contributions
* quite creative and may make unique and original contributions
*capable of passionate [[endurance]] in certain spheres of interest
* capable of passionate [[endurance]] in certain spheres of interest
|-
|-
|Love and sexuality
|Love and sexuality
|
|
*[[Asexuality|asexual]], sometimes [[celibate]]
* [[Asexuality|asexual]], sometimes [[celibate]]
*free of [[romantic interest]]s
* free of [[Romantic interest|romantic interests]]
*averse to sexual [[gossip]] and [[innuendo]]
* averse to sexual [[gossip]] and [[innuendo]]
|
|
*secret [[voyeuristic]] interests
* secret [[voyeuristic]] interests
*vulnerable to [[erotomania]]
* vulnerable to [[erotomania]]
*tendency towards [[compulsive]] [[perversions]]
* tendency towards [[compulsive]] [[perversions]]
|-
|-
|Ethics, standards, and ideals
|Ethics, standards, and ideals
|
|
*[[idiosyncratic]] moral and political beliefs
* [[idiosyncratic]] moral and political beliefs
*tendency towards spiritual, mystical and [[Parapsychology|para-psychological]] interests
* tendency towards spiritual, mystical and [[Parapsychology|para-psychological]] interests
|
|
*moral unevenness
* moral unevenness
*occasionally strikingly [[Amorality|amoral]] and vulnerable to odd crimes, at other times [[altruistic]]ally self-sacrificing
* occasionally strikingly [[Amorality|amoral]] and vulnerable to odd crimes, at other times [[Altruistic|altruistically]] self-sacrificing
|-
|-
|[[Cognitive style]]
|[[Cognitive style]]
|
|
*[[absent-minded]]
* [[absent-minded]]
*engrossed in fantasy
* engrossed in fantasy
*vague and [[stilted speech]]
* vague and [[stilted speech]]
*alternations between [[eloquence]] and inarticulateness
* alternations between [[eloquence]] and inarticulateness
|
|
*[[Glossary of psychiatry#autistic thinking|autistic thinking]]
* [[Glossary of psychiatry#autistic thinking|autistic thinking]]
*fluctuations between sharp contact with external reality and hyperreflectiveness about the [[self]]
* fluctuations between sharp contact with external reality and hyperreflectiveness about the [[self]]
*autocentric use of language
* autocentric use of language
|}
|}


=== Differential Diagnosis ===
====Millon's subtypes====
[[Theodore Millon]] restricted the term "schizoid" to those personalities who lack the capacity to form social relationships. He characterizes their way of thinking as being vague and void of thoughts and as sometimes having a "defective perceptual scanning". Because they often do not perceive cues that trigger [[affective]] responses, they experience fewer emotional reactions.<ref name="beckfreeman" /><ref>{{Cite book|url=https://books.google.com/books?id=kYsRDAAAQBAJ&q=schizoid+%22perceptual+scanning%22&pg=PA207|title=Understanding Anger Disorders|last1=DiGiuseppe|first1=Raymond|last2=Tafrate|first2=Raymond Chip|date=2007|publisher=Oxford University Press, USA|isbn=9780195170795|pages=207|language=en}}</ref>

For Millon, SzPD is distinguished from other personality disorders in that it is "the personality disorder that lacks a personality." He criticizes that this may be due to the current diagnostic criteria: They describe SzPD only by an absence of certain traits, which results in a "deficit syndrome" or "vacuum". Instead of delineating the presence of something, they mention solely what is lacking. Therefore, it is hard to describe and research such a concept.<ref name="Millon 11" />

He identified four subtypes of SzPD. Any individual schizoid may exhibit none or one of the following:<ref name="Millon 11" /><ref name="millon9">{{cite web|url=http://www.millonpersonality.com/theory/diagnostic-taxonomy/schizoid.htm|title=Theodore Millon – The Retiring or Schizoid Personality|publisher=millonpersonality.com}}</ref>

{| class="wikitable"
{| class="wikitable"
|-
|+
!Psychological condition
! Subtype
!Features
!Features
|-
|-
|Other mental disorders with [[Psychosis|psychotic symptoms]]
| '''Languid schizoid''' (including [[dependent personality disorder|dependent]] and [[depressive personality disorder|depressive]] features)
|Symptoms of Schizoid Personality Disorder can appear during the course of disorder with psychotic features such as [[delusional disorder]]. However, SzPD does not require the presence of any psychotic symptoms such as [[Hallucination|hallucinations]] or [[Delusion|delusions]].<ref name=":64">{{Cite book |url=https://archive.org/details/info_munsha_DSM5/page/n1/mode/2up |title=Diagnostic And Statistical Manual Of Mental Disorders |date=May 18, 2013 |publisher=[[American Psychiatric Association]] |isbn=978-0-89042-554-1 |edition=5th |location=[[Arlington]], [[Virginia]] |pages=652-655 |language=En |archive-url=https://archive.org/details/info_munsha_DSM5/page/n3/mode/2up |archive-date=April 11, 2019 |url-status=live}}</ref>
| Marked inertia; deficient activation level; intrinsically phlegmatic, lethargic, weary, leaden, lackadaisical, exhausted, enfeebled. Unable to act with spontaneity or seeks simplest pleasures, may experience profound angst, yet lack the vitality to express it strongly.
|-
|-
|[[Depression (mood)|Depression]]
| '''Remote schizoid''' (including [[avoidant personality disorder|avoidant]] features)
|People who have SzPD may also have clinical depression. However, this is not always the case. Unlike people with depression, persons with SzPD generally do not consider themselves inferior to others. They may recognize instead that they are "different".
| Distant and removed; inaccessible, solitary, isolated, homeless, disconnected, secluded, aimlessly drifting; peripherally occupied. Seen among people who would have been otherwise capable of developing normal emotional life but having been subjected to intense hostility lost their innate capability to form bonds. Some residual anxiety is present.
|-
|-
|[[Autism spectrum|Autism Spectrum Disorder]]
| '''Depersonalized schizoid''' (including [[schizotypal personality disorder|schizotypal]] features)
|There may be substantial difficulty in distinguishing Asperger syndrome (AS), sometimes called "schizoid disorder of childhood", from SzPD. But while AS is an [[autism spectrum disorder]], SzPD is classified as a "schizophrenia-like" personality disorder. There is some overlap, as some people with [[autism]] also qualify for a diagnosis of schizotypal or schizoid PD. However, one of the distinguishing features of schizoid PD is a restricted affect and an impaired capacity for emotional experience and expression. Persons with AS are "hypo-mentalizers", i.e., they fail to recognize social cues such as verbal hints, body language and gesticulation, but those with schizophrenia-like personality disorders tend to be "hyper-mentalizers", overinterpreting such cues in a generally suspicious way.<ref>{{cite journal |last1=Lenzenweger |first1=Mark |last2=Wastler |first2=Heather |year=2019 |title=Self-referential hypermentalization in schizotypy. |url=https://psycnet.apa.org/record/2019-30029-001 |journal=Personality Disorders: Theory, Research, and Treatment |volume=10 |issue=6 |pages=536–544 |doi=10.1037/per0000344 |pmid=31144838 |s2cid=169040276}}</ref><ref>{{cite journal |last1=Somma |first1=Antonella |last2=Ferrara |first2=Mauro |last3=Terrinoni |first3=Arianna |last4=Frau |first4=Claudia |last5=Ardizzone |first5=Ignazio |last6=Sharp |first6=Carla |last7=Fossati |first7=Andrea |date=April 2019 |title=Hypermentalizing as a marker of borderline personality disorder in Italian adolescents: a cross-cultural replication of Sharp and colleagues' (2011) findings |journal=Borderline Personality Disorder and Emotion Dysregulation |volume=6 |page=5 |doi=10.1186/s40479-019-0104-5 |pmc=6457008 |pmid=31007932}}</ref><ref>{{cite journal |last1=Ciaramidaro |first1=Angela |last2=Bolte |first2=Sven |last3=Schlitt |first3=Sabine |last4=Hainz |first4=Daniela |last5=Poustka |first5=Fritz |last6=Weber |first6=Berndard |last7=Bara |first7=Bruno |last8=Freitag |first8=Christine |last9=Walter |first9=Henrik |date=January 2015 |title=Schizophrenia and autism as contrasting minds: neural evidence for the hypo-hyper-intentionality hypothesis |journal=Schizophrenia Bulletin |volume=41 |issue=1 |pages=171–9 |doi=10.1093/schbul/sbu124 |pmc=4266299 |pmid=25210055}}</ref> Although they may have been socially isolated from childhood onward, most people with SzPD displayed well-adapted social behavior as children, along with apparently normal emotional function. SzPD also does not require impairments in [[nonverbal communication]] such as a [[Asperger syndrome#Social interaction|lack]] of [[eye contact]], [[Asperger syndrome#Speech and language|unusual]] [[Prosody (linguistics)|prosody]] or a pattern of [[Asperger syndrome#Restricted and repetitive interests and behavior|restricted interests or repetitive behaviors]].<ref name="PMID24290364">{{cite journal |author1=Fritz-Georg Lehnhardt |author2=Astrid Gawronski |author3=Kathleen Pfeiffer |author4=Hanna Kockler |author5=Leonhard Schilbach |author6=Kai Vogeley |year=2013 |title=The investigation and differential diagnosis of Asperger syndrome in adults |journal=Deutsches Ärzteblatt International |volume=110 |issue=45 |pages=755–63 |doi=10.3238/arztebl.2013.0755 |pmc=3849991 |pmid=24290364}}</ref>
| Disengaged from others and self; self is disembodied or distant object; body and mind sundered, cleaved, dissociated, disjoined, eliminated. Often seen as simply staring into the empty space or being occupied with something substantial while actually being occupied with nothing at all.
|-
|-
|Personality change due to another medical condition
| '''Affectless schizoid''' (including [[obsessive-compulsive personality disorder|compulsive]] features)
|Traits of Schizoid Personality Disorder can appear due to damage to the [[central nervous system]].<ref name=":63">{{Cite book |url=https://archive.org/details/info_munsha_DSM5/page/n1/mode/2up |title=Diagnostic And Statistical Manual Of Mental Disorders |date=May 18, 2013 |publisher=[[American Psychiatric Association]] |isbn=978-0-89042-554-1 |edition=5th |location=[[Arlington]], [[Virginia]] |pages=652-655 |language=En |archive-url=https://archive.org/details/info_munsha_DSM5/page/n3/mode/2up |archive-date=April 11, 2019 |url-status=live}}</ref>
| Passionless, unresponsive, unaffectionate, chilly, uncaring, unstirred, spiritless, lackluster, unexcitable, unperturbed, cold; all emotions diminished. Combines the preference for rigid schedule (obsessive-compulsive feature) with the coldness of the schizoid.
|}

==Causes==
{{further information|Schizotypy#Possible biological bases of schizotypy}}
Some evidence suggests the cluster A personality disorders have shared genetic and environmental risk factors, and there is an increased prevalence of SzPD in relatives of people with [[schizophrenia]] and [[schizotypal personality disorder]].<ref name="ClusterA" /> [[Twin studies]] with SzPD traits (e.g. low sociability and low warmth) suggest these are inherited. Besides this indirect evidence, the direct heritability estimates of SzPD range from 50 to 59%.<ref>{{cite journal |last1=Kendler |first1=Kenneth S. |last2=Czajkowski |first2=Nikolai |last3=Tambs |first3=Kristian |last4=Torgersen |first4=Svenn |last5=Aggen |first5=Steven H. |last6=C. Neale |first6=Michael |last7=Reichborn-Kjennerud |first7=Ted |title=Dimensional representations of DSM-IV Cluster A personality disorders in a population-based sample of Norwegian twins: a multivariate study |journal=Psychological Medicine |date=November 2006 |volume=36 |issue=11 |pages=1583–1591 |doi=10.1017/S0033291706008609 |pmid=16893481 |s2cid=21613637 }}</ref><ref name="Blaney2014">{{cite book|url=https://books.google.com/books?id=NQ0bBAAAQBAJ&pg=PA639|title=Oxford Textbook of Psychopathology|date=2014|publisher=Oxford University Press|isbn=978-0-19-981184-7|page=649|author1=Paul H. Blaney}}</ref> To [[Sula Wolff]], who did extensive research and clinical work with children and teenagers with schizoid symptoms, "schizoid personality has a constitutional, probably genetic, basis."<ref name=":8">{{cite book|url=https://books.google.com/books?id=Oo9kWqaGqkoC|title=Loners – The Life Path of Unusual Children|publisher=Routledge|year=1995|isbn=978-0-415-06665-5|page=35|last1=Sula Wolff|author-link1=Sula Wolff}}</ref> The link between SzPD and being [[underweight]] may also point to the involvement of biological factors.<ref name="Millon 11">{{cite book|last1=Millon|first1=Theodore |author-link1=Theodore Millon|last2=Millon|first2=Carrie M. |last3=Meagher|first3=Sarah E. |others=Seth D. Grossman, Rowena Ramnath|title=Personality Disorders in Modern Life|url=https://archive.org/details/personalitydisor00mill|url-access=limited|edition=2nd|year=2012|publisher=John Wiley & Sons|isbn=978-0-471-23734-1|pages=[https://archive.org/details/personalitydisor00mill/page/n387 371]–374|chapter=The Schizoid Personality (Chapter 11)}}</ref><ref>{{Cite journal|last=Amber A. Mather|year=2008|title=Associations Between Body Weight and Personality Disorders in a Nationally Representative Sample|journal=Psychosomatic Medicine|volume=70|issue=9|pages=1012–1019|doi=10.1097/psy.0b013e318189a930|pmid=18842749|s2cid=26386820}}</ref>

In general, prenatal caloric [[malnutrition]], [[Preterm birth|premature birth]] and a low birth weight are risk factors for having a [[mental disorder]] and may contribute to the development of SzPD as well. Those who have experienced [[traumatic brain injury]] may be also at risk of developing features reflective of SzPD.<ref>{{cite journal|year=2010|title=Birth weight, schizophrenia, and adult mental disorder: is risk confined to the smallest babies?|journal=Archives of General Psychiatry|volume=67|issue=9|pages=923–930|doi=10.1001/archgenpsychiatry.2010.100|last1=Kathryn M. Abel|pmid=20819986|doi-access=free}}</ref><ref name="Martins2010">{{cite journal |last1=Martens |first1=Willem H.J. |title=Schizoid personality disorder linked to unbearable and inescapable loneliness |journal=The European Journal of Psychiatry |date=March 2010 |volume=24 |issue=1 |doi=10.4321/S0213-61632010000100005 |doi-access=free }}</ref><ref>Brigham Young University (2014): [http://news.byu.edu/news/head-injuries-can-make-children-loners Head injuries can make children loners.] For original study, see {{cite journal|doi=10.1097/HTR.0000000000000040 | pmid=24714213 | volume=30 | issue=2 | title=Right Frontal Pole Cortical Thickness and Social Competence in Children With Chronic Traumatic Brain Injury | journal=Journal of Head Trauma Rehabilitation | pages=E24–E31| year=2015 | last1=Levan | first1=Ashley | last2=Baxter | first2=Leslie | last3=Kirwan | first3=C. Brock | last4=Black | first4=Garrett | last5=Gale | first5=Shawn D | s2cid=20443326 }}</ref>

Other historical researchers had hypothesized excessively [[Perfectionism (psychology)|perfectionist]],<ref>{{cite journal | title = The Schizoid Child | journal = [[American Journal of Orthopsychiatry]] | date = April 1946 |author1=R.L. Jenkins |author2=S. Glickman | volume = 16 | issue = 2 | pages = 255–61|doi=10.1111/j.1939-0025.1946.tb05379.x }}</ref> unloving or neglectful parenting could play a role.

==Diagnosis==
===DSM-5 criteria===
The ''[[Diagnostic and Statistical Manual of Mental Disorders]]'' is a widely used manual for diagnosing mental disorders. [[DSM-5]] includes SzPD with the same criteria as in [[DSM-IV]]. In the DSM-5, SzPD is described as a pervasive pattern of detachment from social relationships and a restricted range of expression of emotions in interpersonal settings, beginning by early adulthood and present in a variety of contexts, as indicated by at least four of the following:<ref name="DSM-5-Schizoid">{{cite book|title=Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (2013)|year=2013|isbn=978-0-89042-555-8|chapter=Schizoid Personality Disorder (pp. 652–655)|chapter-url-access=registration|chapter-url=https://archive.org/details/diagnosticstatis0005unse}}</ref>

# Neither desires nor enjoys close relationships, including being part of a family.
# Almost always chooses solitary activities.
# Has little, if any, interest in having sexual experiences with another person.
# Takes pleasure in few, if any, activities.
# Lacks close friends or confidants other than first-degree relatives.
# Appears indifferent to the praise or criticism of others.
# Shows emotional coldness, detachment, or flattened affectivity.

According to the DSM, those with SzPD may often be unable to, or will rarely express [[aggressiveness]] or [[hostility]], even when provoked directly. These individuals can seem vague or drifting about their goals and their lives may appear directionless. Others view them as indecisive in their actions, [[Introspection|self-absorbed]], [[absent-minded]] and detached from their surroundings. Excessive daydreaming is often present. In cases with severe defects in the capacity to form social relationships, dating and marriage may not be possible.<ref name=":11">Descriptions from [[DSM-III]] (1980) and [[DSM-5]] (2013):"[https://web.archive.org/web/20170202002500/http://displus.sk/DSM/subory/dsm3.pdf#323 Schizoid PD, Associated features (p. 310)]" and [https://books.google.com/books?id=-JivBAAAQBAJ "Schizoid PD (p. 652–655)]".</ref>

===ICD-10 criteria===
The Classification of Mental and Behavioural Disorders of [[ICD-10]] lists SzPD under ([http://apps.who.int/classifications/icd10/browse/2016/en#/F60.1 F60.1]).<ref name="ICD10Green">{{Cite book |chapter-url=https://www.who.int/docs/default-source/classification/other-classifications/grnbook.pdf?sfvrsn=8e11345b_2 |title=The ICD-10 Classification of Mental and Behavioural Disorders – Diagnostic criteria for research |publisher=[[World Health Organization]] |location=Geneva |page=149 |chapter=F60 Specific personality disorders}}</ref>

The [[Personality disorder#DSM-5 general criteria|general criteria]] of personality disorder (F60) should be met first. In addition, at least four of the following criteria must be present:

* Few, if any, activities provide pleasure.
* Displays emotional coldness, [[Emotional detachment|detachment]], or [[flattened affectivity]].
* Limited capacity to express warm, tender feelings for others as well as anger.
* Appears indifferent to either praise or criticism from others.
* Little interest in having sexual experiences with another person (taking into account age).
* Almost always chooses solitary activities.
* Excessive preoccupation with [[Fantasy (psychology)|fantasy]] and introspection.
* Neither desires, nor has, any close friends or confiding relationships (or only one).
* Marked insensitivity to prevailing [[social norm]]s and [[convention (norm)|convention]]s; if these are not followed, this is unintentional.

===Guntrip criteria===
Ralph Klein, Clinical Director of the [[James F. Masterson|Masterson]] Institute, delineates the following nine characteristics of the schizoid personality as described by [[Harry Guntrip]]:<ref name="Klein6"/>{{rp|13–23}}

* [[Introversion]]
* [[Solitude|Withdrawnness]]
* [[Narcissism]]
* [[Self-sufficiency]]
* [[Grandiosity|Sense of superiority]]
* [[Reduced affect display|Loss of affect]]
* [[Loneliness]]
* [[Depersonalization]]
* [[Regression (psychology)|Regression]]

The description of Guntrip's nine characteristics should clarify some differences between the traditional DSM portrait of SzPD and the traditional informed [[object relations]] view. All nine characteristics are consistent. Most, if not all, must be present to diagnose a schizoid disorder.<ref name="Klein6"/>

=== Differential diagnosis ===
While SzPD shares several symptoms with other [[mental disorder]]s, there are some important differentiating features.

{| class="wikitable"
|-
|-
|[[Substance use disorder|Substance use Disorders]]
! Psychological condition
|Traits of Schizoid Personality Disorder can appear due to [[substance abuse]].<ref name=":62">{{Cite book |url=https://archive.org/details/info_munsha_DSM5/page/n1/mode/2up |title=Diagnostic And Statistical Manual Of Mental Disorders |date=May 18, 2013 |publisher=[[American Psychiatric Association]] |isbn=978-0-89042-554-1 |edition=5th |location=[[Arlington]], [[Virginia]] |pages=652-655 |language=En |archive-url=https://archive.org/details/info_munsha_DSM5/page/n3/mode/2up |archive-date=April 11, 2019 |url-status=live}}</ref>
! Features
|-
|-
|Other [[Personality disorder|personality disorders]] and [[Trait theory|personality traits]]
| [[Depression (mood)|Depression]]
|Schizoid and [[Narcissistic personality disorder|narcissistic personality disorders]] can seem similar in some respects (e.g. both show identity confusion, may lack warmth and spontaneity, avoid deep relationships with intimacy). Another commonality observed by Akhtar is preferring ideas over people and displaying "intellectual hypertrophy", with a corresponding lack of rootedness in bodily existence. There are, nonetheless, important differences. The schizoid hides his need for dependency and is rather fatalistic, passive, cynical, overtly bland or vaguely mysterious. The narcissist is, in contrast, ambitious and competitive and exploits others for his dependency needs.<ref>{{Cite book |last=Akhtar |first=Salman |url=http://www.sakkyndig.com/psykologi/artvit/akhtar2000.pdf |title=The Shy Narcissist |date=August 1, 2000 |work=Changing Ideas in a Changing World |publisher=Karnac Books |year= |isbn=978-189-274-673-3 |edition=1st |page=117 |language=en |author-link=Salman Akhtar |access-date=2022-10-04 |archive-url=https://web.archive.org/web/20210507081937/http://www.sakkyndig.com/psykologi/artvit/akhtar2000.pdf |archive-date=May 7, 2021 |url-status=live}}</ref> There are also parallels between SzPD and [[Obsessive–compulsive personality disorder|obsessive-compulsive personality disorder]] (OCPD), such as detachment, restricted emotional expression and rigidity. However, in OCPD the capacity to develop intimate relationships is usually intact, but deep contacts may be avoided because of an unease with emotions and a devotion to work.<ref name=":113">Descriptions from [[DSM-III]] (1980) and [[DSM-5]] (2013):"[https://web.archive.org/web/20170202002500/http://displus.sk/DSM/subory/dsm3.pdf#323 Schizoid PD, Associated features (p. 310)]" and [https://books.google.com/books?id=-JivBAAAQBAJ "Schizoid PD (p. 652–655)]".</ref><ref name="Akhtar22">{{cite book |author=Akhtar |first=Salman |url=https://books.google.com/books?id=bU0eAAAAQBAJ&pg=PA121 |title=Schizoid Personality Disorder: A Synthesis of Developmental, Dynamic, and Descriptive Features |journal=American Journal of Psychotherapy |year=1987 |isbn=9781461627685 |volume=41 |pages=499–518 |doi=10.1176/appi.psychotherapy.1987.41.4.499 |pmid=3324773 |author-link=Salman Akhtar |access-date=2017-02-10 |archive-url=https://web.archive.org/web/20170731160223/https://books.google.de/books?id=bU0eAAAAQBAJ&pg=PA121 |archive-date=2017-07-31 |url-status=live |issue=4}}</ref> While people affected with APD avoid social interactions due to anxiety or feelings of incompetence, those with SzPD do so because they are genuinely indifferent to social relationships. A 1989 study,<ref>{{cite journal |last=James Overholser (1989) |date=November 1989 |title=Differentiation between schizoid and avoidant personalities: an empirical test |journal=Canadian Journal of Psychiatry |volume=34 |issue=8 |pages=785–90 |doi=10.1177/070674378903400808 |pmid=2819642 |s2cid=6222302}}</ref> however, found that "schizoid and avoidant personalities were found to display equivalent levels of anxiety, depression, and psychotic tendencies as compared to psychiatric control patients." There also seems to be some shared genetic risk between SzPD and AvPD (see [[Schizoid avoidant behavior|schizoid-avoidant behavior]]). Several sources have confirmed the synonymy of SzPD and [[Attachment in adults#Dismissive-avoidant|avoidant attachment style]].<ref>{{Cite book |last=Malcolm L. West and A. E. Sheldon-Keller |url=https://books.google.com/books?id=_cY9HsmiOCcC&pg=PR12 |title=Patterns of Relating An Adult Attachment Perspective |publisher=Guilford Press |year=1994 |isbn=978-0-89862-671-1 |location=New York |pages=111–113}}</ref> However, the distinction should be made that individuals with SzPD characteristically do not seek social interactions merely due to lack of interest, while those with avoidant attachment style can in fact be interested in interacting with others but without establishing connections of much depth or length due to having little tolerance for any kind of intimacy.
| People who have SzPD may also have clinical depression. However, this is not always the case. Unlike people with depression, persons with SzPD generally do not consider themselves [[Inferiority complex|inferior to others]]. They may recognize instead that they are "different".
|-
| [[Avoidant personality disorder]]
| While people affected with avoidant personality disorder (AvPD) avoid social interactions due to anxiety or feelings of incompetence, those with SzPD do so because they are genuinely indifferent to social relationships. A 1989 study,<ref>{{cite journal|last=James Overholser (1989)|title=Differentiation between schizoid and avoidant personalities: an empirical test|journal=Canadian Journal of Psychiatry|volume=34|issue=8|pages=785–90|doi=10.1177/070674378903400808|pmid=2819642|date=November 1989|s2cid=6222302}}</ref> however, found that "schizoid and avoidant personalities were found to display equivalent levels of anxiety, depression, and psychotic tendencies as compared to psychiatric control patients." There also seems to be some shared genetic risk between SzPD and AvPD (see [[Schizoid avoidant behavior|schizoid-avoidant behavior]]). Several sources have confirmed the synonymy of SzPD and [[Attachment in adults#Dismissive-avoidant|avoidant attachment style]].<ref>{{Cite book|url=https://books.google.com/books?id=_cY9HsmiOCcC&pg=PR12|title=Patterns of Relating An Adult Attachment Perspective|last=Malcolm L. West and A. E. Sheldon-Keller|publisher=Guilford Press|year=1994|isbn=978-0-89862-671-1|location=New York|pages=111–113}}</ref> However, the distinction should be made that individuals with SzPD characteristically do not seek social interactions merely due to lack of interest, while those with avoidant attachment style can in fact be interested in interacting with others but without establishing connections of much depth or length due to having little tolerance for any kind of intimacy.
|-
| [[Narcissistic personality disorder]]
| Schizoid and narcissistic personality disorders can seem similar in the presence of identity confusion, lack of warmth and spontaneity, and avoidance of deep relationships with intimacy. Another commonality observed by Akhtar is preferring ideas over people and displaying "intellectual hypertrophy" with a corresponding lack of rootedness in bodily existence. There are, nonetheless, important differences. The schizoid hides his need for dependency and is rather fatalistic, passive, cynical, overtly bland or vaguely mysterious. The narcissist is, in contrast, ambitious and competitive and exploits others for his dependency needs.

Sense of superiority in SzPD is very different from the [[grandiosity]] seen in narcissistic personality disorder, which is described as "burdened with envy" and with a desire to destroy or put down others. Additionally, schizoids do not go out of their way to achieve social validation.<ref name=":03">{{cite thesis |id={{ProQuest|1476206281}} |last1=Wheeler |first1=Zachary |year=2013 |title=Treatment of schizoid personality: An analytic psychotherapy handbook }}</ref>{{rp|60}} Unlike the narcissist, the schizoid will often keep their creations private to avoid unwelcome attention or the feeling that their ideas and thoughts are being appropriated by the public.<ref name=":03" />{{rp|174}}
|-
| [[Obsessive–compulsive personality disorder]]
| There are also parallels between SzPD and obsessive–compulsive personality disorder (OCPD), such as detachment, restricted emotional expression and rigidity. However, in OCPD the capacity to develop intimate relationships is usually intact, but deep contacts may be avoided because of an unease with emotions and a devotion to work.<ref name="Akhtar" /><ref name=":11" />
|-
| [[Asperger syndrome]]
| There may be substantial difficulty in distinguishing Asperger syndrome (AS) from SzPD. But while AS is an [[autism spectrum]] disorder, SzPD is classified as a "[[Spectrum disorder#Schizophrenia-like personality disorders|schizophrenia-like]]" personality disorder. There is some overlap, as some people with autism also meet schizotypal or schizoid diagnostic criteria. However, one distinct feature of SzPD is a restricted affect and an impaired capacity for emotional experience and expression. Persons with AS are "hypo-mentalizers", i.e., they fail to recognize social cues such as verbal hints, body language and gesticulation, but those with schizophrenia-like personality disorders tend to be "hyper-mentalizers", overinterpreting such cues in a generally suspicious way.<ref>{{cite journal |last1=Lenzenweger |first1=Mark |last2=Wastler |first2=Heather |title=Self-referential hypermentalization in schizotypy. |journal=Personality Disorders: Theory, Research, and Treatment |year=2019 |volume=10 |issue=6 |pages=536–544 |doi=10.1037/per0000344 |pmid=31144838 |s2cid=169040276 |url=https://psycnet.apa.org/record/2019-30029-001}}</ref><ref>{{cite journal |last1=Somma |first1=Antonella |last2=Ferrara |first2=Mauro |last3=Terrinoni |first3=Arianna |last4=Frau |first4=Claudia |last5=Ardizzone |first5=Ignazio |last6=Sharp |first6=Carla |last7=Fossati |first7=Andrea |title=Hypermentalizing as a marker of borderline personality disorder in Italian adolescents: a cross-cultural replication of Sharp and colleagues' (2011) findings |journal=Borderline Personality Disorder and Emotion Dysregulation |date=April 2019 |volume=6 |page=5 |doi=10.1186/s40479-019-0104-5 |pmid=31007932 |pmc=6457008 }}</ref><ref>{{cite journal |last1=Ciaramidaro |first1=Angela |last2=Bolte |first2=Sven |last3=Schlitt |first3=Sabine |last4=Hainz |first4=Daniela |last5=Poustka |first5=Fritz |last6=Weber |first6=Berndard |last7=Bara |first7=Bruno |last8=Freitag |first8=Christine |last9=Walter |first9=Henrik |title=Schizophrenia and autism as contrasting minds: neural evidence for the hypo-hyper-intentionality hypothesis |journal=Schizophrenia Bulletin |date=January 2015 |volume=41 |issue=1 |pages=171–9 |doi=10.1093/schbul/sbu124 |pmid=25210055|pmc=4266299 }}</ref>

Although they may have been socially isolated from childhood onward, most people with SzPD displayed well-adapted social behavior as children, along with apparently normal emotional function. SzPD also does not require impairments in [[nonverbal communication]] such as a [[Asperger syndrome#Social interaction|lack]] of [[eye contact]], [[Asperger syndrome#Speech and language|unusual]] [[Prosody (linguistics)|prosody]] or a pattern of [[Asperger syndrome#Restricted and repetitive interests and behavior|restricted interests or repetitive behaviors]].<ref name="PMID24290364">{{cite journal|author1=Fritz-Georg Lehnhardt|author2=Astrid Gawronski|author3=Kathleen Pfeiffer|author4=Hanna Kockler|author5=Leonhard Schilbach|author6=Kai Vogeley|year=2013|title=The investigation and differential diagnosis of Asperger syndrome in adults|journal= Deutsches Ärzteblatt International|volume=110|issue=45|pages=755–63|doi=10.3238/arztebl.2013.0755|pmc=3849991|pmid=24290364}}</ref>
|-
| [[Simple-type schizophrenia]]
| The simple-type schizophrenia diagnosis is present in the [[ICD-10]] but not in the [[DSM-5]] or the [[ICD-11]].<ref>World Health Organization (1993) – [https://www.who.int/classifications/icd/en/bluebook.pdf The ICD-10 Classification of Mental and Behavioural Disorders]. "Simple schizophrenia" is classified F20.6.</ref><ref name=":23">{{Cite web|url=https://icd.who.int/browse11/l-m/en#/http://id.who.int/icd/entity/1683919430/mms/unspecified|title=ICD-11 - Mortality and Morbidity Statistics|publisher=World Health Organization|access-date=2019-08-22}}</ref> It is characterised by [[negative symptoms]] without [[psychotic]] features. Both simple-type schizophrenia and SzPD share many negative symptoms like [[avolition]], impoverished thinking and [[flat affect]]. Although they may look almost identical, what distinguishes them is usually the severity. Also, SzPD is characterized by a lifelong pattern without change, whereas simple-type schizophrenia represents a deterioration.<ref>{{cite book |section=Appendix B: Criteria Sets and Axes Provided for Further Study |title=Diagnostic and Statistical Manual of Mental Disorders |edition=4th |date=1994 |isbn=9780890420621 |page=[https://archive.org/details/diagnosticstatis00amer_0/page/713 713] |publisher=American Psychiatric Association |url=https://archive.org/details/diagnosticstatis00amer_0 |url-access=registration}}</ref>
|}
|}


=== Comorbidity ===
== See also ==
{{Portal|Psychology
SzPD is often found to be comorbid with several disorders or pathologies. Persons with SzPD may meet criteria for an additional personality disorder, most often [[avoidant personality disorder]], [[schizotypal personality disorder]] or [[paranoid personality disorder]].<ref name=":5">{{Cite book|title=Integrated Treatment for Co-Occurring Disorders: Personality Disorders and Addiction|last=Sharon C. Ekleberry|publisher=Routledge|year=2008|isbn=978-0789036933|pages=31–32|chapter=Cluster A - Schizoid Personality Disorder and Substance Use Disorders|chapter-url=https://books.google.com/books?id=O5HY1xcfjEcC&pg=PA31}}</ref> [[Alexithymia]] (the inability to identify and describe emotions) is often present in SzPD.<ref>{{cite journal |last1=Coolidge |first1=Frederick L. |last2=Estey |first2=Alisa J. |last3=Segal |first3=Daniel L. |last4=Marle |first4=Peter D. |title=Are alexithymia and schizoid personality disorder synonymous diagnoses? |journal=Comprehensive Psychiatry |date=February 2013 |volume=54 |issue=2 |pages=141–148 |doi=10.1016/j.comppsych.2012.07.005 |pmid=23021894 |s2cid=15019411 }}</ref> Sharon Ekleberry suggests that some people with schizoid personality features may occasionally experience instances of [[brief reactive psychosis]] when under stress.<ref name=":5" />
}}

==== Substance use disorder ====
Very little data exists for rates of [[substance use disorder]] among people with SzPD, but existing studies suggest they are less likely to have [[substance abuse]] problems than the general population. One study found that significantly fewer boys with SzPD had alcohol problems than a control group of non-schizoids.<ref name=":18" /> Another study evaluating personality disorder profiles in substance abusers found that substance abusers who showed schizoid symptoms were more likely to abuse one substance rather than many, in contrast to other personality disorders such as [[Borderline personality disorder|borderline]], [[Antisocial personality disorder|antisocial]] or [[Histrionic personality disorder|histrionic]], which were more likely to abuse many.<ref>{{cite journal |last1=Skinstad |first1=Anne Helene |last2=Swain |first2=Annette |title=Comorbidity in a Clinical Sample of Substance Abusers |journal=The American Journal of Drug and Alcohol Abuse |date=January 2001 |volume=27 |issue=1 |pages=45–64 |doi=10.1081/ada-100103118 |pmid=11373036 |s2cid=2619787 }}</ref>

American psychotherapist Sharon Ekleberry states that the impoverished social connections experienced by people with SzPD limit their exposure to the drug culture and that they have limited inclination to learn how to do [[narcotic]]s. Describing them as "highly resistant to [[Peer pressure|influence]]", she additionally states that even if they could access illegal drugs, they would be disinclined to use them in public or social settings, and because they would be more likely to use alcohol or cannabis alone than for social [[disinhibition]], they would not be particularly susceptible to negative consequences in early use.<ref name=":5" />

==== Suicide ====
[[Suicide]] may be a running theme for schizoid individuals, in part due to the knowledge of the large-scale ostracism that would result if their idiosyncratic views were revealed and their experience that most, if not all people, are unrelatable or have polar opposite reactions to them on societally sensitive issues, though they are not likely to actually attempt it. They might be down and depressed when all possible connections have been cut off, but as long as there is some relationship or even hope for one the risk will be low. The idea of suicide is a driving force against the person's schizoid defenses. Often among people with SzPD, there is a rationally grounded and reasoned position on why they want to die, and this "suicidal construct" takes a stable position in the mind.

The characteristics of the premorbidities ([[schizothymia]], [[autism]], [[anhedonia]]) also affected suicidal behaviour. Suicide attempts were always genuine in nature, well-planned, and it was only by chance that patients survived (usually the fatal outcome was prevented by the sudden appearance of others). They denied the existence of suicidal experiences earlier, but argued that in the current circumstances, suicide seemed to them the most appropriate way out. Important in all these cases was the absence of any significant anti-suicidal factors (most were found in a situation of relative social isolation; there were no professional and personal interests). The high ability to introspect in these cases only increased the isolation from reality, rendering the choice of suicide more reasonable.<ref name=":20" />

A mini-review indicates that SzPD or schizoid traits are a major risk factor for both suicide attempts and suicide,<ref name="PsychiatriaDanubina" /> but schizoids tend to hide their suicidal thoughts and intentions. Demonstrative suicides or suicide blackmail, as seen in [[cluster B personality disorders]] such as borderline, histrionic or antisocial, are extremely rare among schizoid individuals.<ref name=":20">{{Cite journal|last1=Анатольевна|first1=Панченко Евгения|last2=Сергеевич|first2=Положий Борис|year=2011|title=Расстройства Личности у Пациентов, Совершивших Суицидальные Попытки|trans-title=Personality Disorders in Patients Who Have Committed Suicide Attempts|url=https://cyberleninka.ru/article/n/rasstroystva-lichnosti-u-patsientov-sovershivshih-suitsidalnye-popytki|journal=Российский психиатрический журнал|issue=3|pages=48–51 }}</ref> As in other clinical mental health settings, among suicidal inpatients, individuals with SzPD are not as well-represented as some other groups. A 2011 study on suicidal inpatients at a Moscow hospital found that schizoids were the least common patients, while those with cluster B personality disorders were the most common.<ref name=":20" />

==== Low weight ====
A study which looked at the [[body mass index]] (BMI) of a sample of both male adolescents diagnosed with SzPD and those diagnosed with Asperger syndrome found that the BMI of all patients was significantly below normal. Clinical records indicated abnormal eating behaviour by some patients. Some patients would only eat when alone and refused to eat out. Restrictive diets and [[Hypochondriasis|fears of disease]] were also found. It was suggested that the anhedonia of SzPD may also cover eating, leading schizoid individuals to not enjoy it. Alternatively, it was suggested that schizoid individuals may not feel hunger as strongly as others or not respond to it, a certain withdrawal "from themselves".<ref name="Millon 11" />

==== Anti-social conduct ====
Another study looked at rates of [[Anti-social behaviour|anti-social conduct]] in boys with either SzPD or Asperger syndrome compared with a control group of non-schizoid individuals and found the incidence of anti-social conduct to be the same in both groups. However, the schizoid boys stole significantly less. Upon follow-up in adulthood, out of a matched group of 19 boys with SzPD and 19 boys without, four of the schizoid boys reported having exclusively internal violent fantasies (concerned with [[Zulu Kingdom|Zulu]] wars, [[abattoirs]], [[fascists]] and [[communists]] and a collection of knives, respectively), which were pursued entirely by themselves, while the only non-schizoid subject to report a violent fantasy life shared his with a group of young men (dressing up and riding motorcycles as a self-styled "[[panzer]]" group).<ref name=":18" />

An absent parent or socio-economic disadvantage did not seem to affect the risk of anti-social conduct in schizoid individuals as much as it did in non-schizoid individuals. Absent parents and parental socio-economic disadvantage were also less common in the schizoid group.<ref name=":18">{{Cite journal|last1=Wolff|first1=S.|last2=Cull|first2=A.|date=August 1986|title='Schizoid' personality and antisocial conduct: a retrospective case not study|journal=Psychological Medicine|volume=16|issue=3|pages=677–687 |pmid=3763781|doi=10.1017/S0033291700010424|s2cid=35166577 }}</ref>

===Distinction from autism spectrum disorders===
Several studies have reported an overlap with [[Asperger syndrome]] which had traditionally been called "schizoid disorder of childhood".<ref name=":16">{{Cite journal|last=Tantam|first=D.|date=December 1988|title=Lifelong eccentricity and social isolation. II: Asperger's syndrome or schizoid personality disorder?|journal=The British Journal of Psychiatry: The Journal of Mental Science|volume=153|pages=783–791|doi=10.1192/bjp.153.6.783 |pmid=3256377|s2cid=39433805}}</ref><ref name=":17" /><ref name=":21" /><ref name=":22">{{Cite journal |last1=Hummelen |first1=Benjamin |last2=Pedersen |first2=Geir |last3=Wilberg |first3=Theresa |last4=Karterud |first4=Sigmund |date=June 2015 |title=Poor Validity of the ''DSM-IV'' Schizoid Personality Disorder Construct as a Diagnostic Category |journal=Journal of Personality Disorders |volume=29 |issue=3 |pages=334–346 |doi=10.1521/pedi_2014_28_159 |pmid=25248009 }}</ref> [[Eugen Bleuler]] coined both the terms "autism" and "schizoid" to describe withdrawal to an internal fantasy, against which any influence from outside becomes an intolerable disturbance.<ref>{{cite journal|vauthors=Kuhn R|year=2004|title=Eugen Bleuler's concepts of psychopathology|journal=Hist Psychiatry|volume=15|issue=3|pages=361–366|doi=10.1177/0957154X04044603|pmid=15386868|s2cid=5317716}} The quote is a translation of Bleuler's 1910 original.</ref> [[Digby Tantam|Tantam]] suggested that Asperger syndrome may confer an increased risk of developing SzPD.<ref name=":16" />

A study from 2012 found that in a sample of 54 young adults with Asperger syndrome, 26% of them also met criteria for SzPD, the highest comorbidity out of any personality disorder in the sample (the other comorbidities were 19% for [[obsessive–compulsive personality disorder]], 13% for [[avoidant personality disorder]] and one female with [[schizotypal personality disorder]]). Additionally, twice as many men with Asperger syndrome met criteria for SzPD than women. While 41% of the whole sample were unemployed with no occupation, this rose to 62% for the Asperger's and SzPD comorbid group.<ref name=":17">{{Cite journal|last1=Lugnegård|first1=Tove|last2=Hallerbäck|first2=Maria Unenge|last3=Gillberg|first3=Christopher|date=May 2012|title=Personality disorders and autism spectrum disorders: what are the connections?|journal=Comprehensive Psychiatry|volume=53|issue=4|pages=333–340|doi=10.1016/j.comppsych.2011.05.014|pmid=21821235}}</ref> It noted that the [[Diagnostic and Statistical Manual of Mental Disorders|DSM]] may complicate diagnosis by requiring the exclusion of a [[pervasive developmental disorder]] (PDD) before establishing a diagnosis of SzPD. The study found that social interaction impairments, stereotyped behaviours and specific interests were more severe in the individuals with Asperger syndrome also fulfilling SzPD criteria, against the notion that social interaction skills are unimpaired in SzPD. The authors believe that a substantial subgroup of people with autism spectrum disorder or PDD have clear "schizoid traits" and correspond largely to the "loners" in [[Lorna Wing]]'s classification ''The autism spectrum'' ([[The Lancet|Lancet]] 1997), described by [[Sula Wolff]].<ref name=":17" />

A study from 2019 found that 54% of a group of males aged 11 to 25 with Asperger syndrome showed significant SzPD traits, with 6% meeting full diagnostic criteria for SzPD, compared to 0% of a control group.<ref name=":21" /> The authors of the study hypothesised that it is extremely likely that historic cohorts of adults diagnosed with SzPD were either misdiagnosed, or they also had childhood-onset autistic syndromes. They stressed that further research to clarify overlap and distinctions between these two syndromes was strongly warranted, especially given that high-functioning [[autism spectrum]] disorders are now recognised in around 1% of the population.<ref name=":19">{{Cite journal |last=Cook |first=Michal |date=2019-05-03 |title=Pronounced Overlap of Autistic and Schizoid Personality Trait Burden in Adolescence |url=https://insar.confex.com/insar/2019/webprogram/Paper30221.html |language=en |website=IMFAR}}</ref>

==Treatment==
People with SzPD rarely seek treatment for their condition. This issue is found in many [[personality disorders]], which prevents many people with these conditions from seeking treatment: they tend to view their condition as [[Egosyntonic and egodystonic|not conflicting with their self-image]] and their abnormal perceptions and behaviors as rational and appropriate. There is little data on the effectiveness of various treatments on this personality disorder because it is seldom seen in clinical settings.<ref name="Medline" /><ref>McVey, D. & Murphy, N. (eds.) (2010) [http://www.routledge.com/books/details/9780415404808/ Treating Personality Disorder: Creating Robust Services for People with Complex Mental Health Needs], {{ISBN|0-203-84115-8}}.</ref>

=== Medication ===
No medications are indicated for directly treating SzPD, but certain medications may reduce the symptoms of SzPD and treat co-occurring [[mental disorders]]. However, it is not general practice to treat SzPD with medications, other than for the short-term treatment of acute co-occurring [[Diagnostic and Statistical Manual of Mental Disorders#DSM-IV multi-axial system|axis I]] conditions such as depression.<ref name="mayoclinic" /> The [[substituted amphetamine]] [[bupropion]] may be used to treat anhedonia. [[Lamotrigine]], [[Selective serotonin reuptake inhibitor|SSRIs]], [[Tricyclic antidepressant|TCAs]], [[Monoamine oxidase inhibitor|MAOIs]] and [[hydroxyzine]] may help counter [[social anxiety]] if it is a concern for people who have SzPD.<ref name="SonnyJoseph" />

The symptoms of SzPD mirror the negative symptoms of schizophrenia, such as [[anhedonia]], [[blunted affect]] and low energy. SzPD is thought to be part of the "[[Spectrum disorder#Psychosis|schizophrenia spectrum]]" of disorders, thus it may benefit from the medications that treat those disorders<ref name="mayoclinic">{{cite web|url=http://www.mayoclinic.org/diseases-conditions/schizoid-personality-disorder/basics/symptoms/con-20029184|title=Schizoid personality disorder|publisher=Mayo Foundation for Medical Education and Research (2016)}}</ref> such as [[modafinil]].<ref>{{cite journal |last1=Scoriels |first1=Linda |last2=Jones |first2=Peter B. |last3=Sahakian |first3=Barbara J. |title=Modafinil effects on cognition and emotion in schizophrenia and its neurochemical modulation in the brain |journal=Neuropharmacology |date=January 2013 |volume=64 |pages=168–184 |doi=10.1016/j.neuropharm.2012.07.011 |pmid=22820555 |s2cid=17975469 }}</ref> Originally, low doses of [[atypical antipsychotics]] like [[risperidone]] or [[olanzapine]] were used to alleviate social deficits and blunted affect.<ref name="SonnyJoseph">{{Cite book|title=Personality Disorders: New Symptom-Focused Drug Therapy|last=Sonny Joseph|publisher=Psychology Press|year=1997|isbn=9780789001344|pages=45–56|chapter=Chapter 3, Schizoid Personality Disorder|chapter-url=https://books.google.com/books?id=KEoPC3_1AGAC&pg=PA45}}</ref> However, a 2012 review concluded that atypical antipsychotics were ineffective for treating personality disorders.<ref name=":15">{{Cite journal|last1=Maher|first1=Alicia R.|last2=Theodore|first2=George|year=2012|title=Summary of the Comparative Effectiveness Review on Off-Label Use of Atypical Antipsychotics|journal=Journal of Managed Care Pharmacy|language=en|volume=18|issue=5 Supp B|pages=S1-20|doi=10.18553/jmcp.2012.18.s5-b.1|pmid=22784311 |doi-access=free}}</ref>

===Psychotherapy===
{{See also|Psychodynamic psychotherapy}}

Despite the relative emotional comfort, psychoanalytic therapy of schizoid individuals takes a long time and causes many difficulties.<ref>{{Cite book|title=Psychoanalytic diagnosis: understanding personality structure in the clinical process|last=McWilliams|first=Nancy|date=1994|publisher=Guilford Press|isbn=0898621992|location=New York|pages=[https://archive.org/details/psychoanalyticdi00mcwi/page/480 480]|oclc=30035262|url=https://archive.org/details/psychoanalyticdi00mcwi/page/480}}</ref> Schizoids are generally poorly involved in psychotherapy due to difficulties in establishing empathic relations with a psychotherapist and low motivation for treatment.<ref>{{Cite book |title=Psychiatry .-- S. . - 512 s. |series=Clinical Recommendations Series |author=Ed. N. G. Neznanova |author2=Yu. A. Alexandrovsky |author3=L. M. Bardenshtein |author4=V. D. Vida |author5=V. N. Krasnov |author6=Yu. V. Popov |publisher=GEOTAR-Media |year=2009 |isbn=978-5-9704-1297-8 |location=Moscow |pages=304–307 |chapter=Chapter 7. F6. Personality Disorders and Behavior in Adults}}</ref>

Supportive psychotherapy is used in an inpatient or outpatient setting by a trained professional that focuses on areas such as coping skills, improvement of social skills and social interactions, communication and self-esteem issues. People with SzPD may also have a perceptual tendency to miss subtle differences in expression. That causes an inability to pick up hints from the environment because social cues from others that might normally provoke an emotional response are not perceived. That in turn limits their own emotional experience.<ref name="beckfreeman" /> The perception of varied events only increases their fear for intimacy and limits them in their interpersonal relationships. Their aloofness may limit their opportunities to refine the social skills and behavior necessary to effectively pursue relationships.{{clarify|reason="miss" what differences? What environmental cues? How does this diffuse experience?|date=November 2012}}

Besides psychodynamic therapy, [[cognitive behavioral therapy]] (CBT) can be used. But because CBT generally begins with identifying the [[Cognitive therapy#Cognitive model|automatic thoughts]], one should be aware of the potential hazards that can happen when working with schizoid patients. People with SzPD seem to be distinguished from those with other personality disorders in that they often report having few or no automatic thoughts at all. That poverty of thought may have to do with their apathetic lifestyle. But another possible explanation could be the paucity of emotion many schizoids display, which would influence their thought patterns as well.<ref name="beckfreeman" />

Socialization groups may help people with SzPD. Educational strategies in which people who have SzPD identify their positive and negative emotions also may be effective. Such identification helps them to learn about their own emotions and the emotions they draw out from others and to feel the common emotions with other people with whom they relate. This can help people with SzPD create empathy with the outside world.{{Citation needed|date=August 2019}}

====Shorter-term treatment====
The concept of "closer compromise" means that the schizoid patient may be encouraged to experience intermediate positions between the extremes of emotional closeness and permanent exile.<ref name="Klein6"/> A lack of injections of interpersonal reality causes an impoverishment in which the schizoid individual's self-image becomes increasingly empty and volatilized and leads the individual to feel unreal.<ref name="Laing1960"/> To create a more adaptive and self-enriching interaction with others in which one "feels real", the patient is encouraged to take risks through greater connection, communication and sharing of ideas, feelings and actions. Closer compromise means that while the patient's vulnerability to anxieties is not overcome, it is modified and managed more adaptively. Here, the therapist repeatedly conveys to the patient that anxiety is inevitable but manageable, without any illusion that the vulnerability to such anxiety can be permanently dispensed with. The limiting factor is the point at which the dangers of intimacy become overwhelming and the patient must again retreat.

Klein suggests that patients must take the responsibility to place themselves at risk and to take the initiative for following through with treatment suggestions in their personal lives. It is emphasized that these are the therapist's impressions and that he or she is not reading the patient's mind or imposing an agenda but is simply stating a position that is an extension of the patient's therapeutic wish. Finally, the therapist directs attention to the need to employ these actions outside of the therapeutic setting.<ref name="Klein6"/>

====Longer-term therapy====
Klein suggests that "working through" is the second longer-term tier of psychotherapeutic work with schizoid patients. Its goals are to change fundamentally the old ways of feeling and thinking and to rid oneself of the vulnerability to those emotions associated with old feelings and thoughts. A new therapeutic operation of "remembering with feeling" that draws on [[Donald Winnicott|D. W. Winnicott]]'s concepts of [[True self and false self|false self and true self]] is called for.<ref name="Klein6"/> The patient must remember with feeling the emergence of his or her false self through childhood and remember the conditions and proscriptions that were imposed on the individual's freedom to experience the self in company with others.<ref name="Klein6"/>

Remembering with feeling ultimately leads the patient to understand that he or she had no opportunity to choose from a selection of possible ways of experiencing the self and of relating with others and had few, if any, options other than to develop a schizoid stance toward others. The false self was simply the best way in which the patient could experience the repetitive predictable acknowledgement, affirmation and approval necessary for emotional survival while warding off the effects associated with the abandonment depression.<ref name="Klein6"/>

If the goal of shorter-term therapy is for patients to understand that they are not the way they appear to be and can act differently, then the longer-term goal of working through is for patients to understand who and what they are as human beings, what they truly are like and what they truly contain. The goal of working through is not achieved by the patient's sudden discovery of a hidden, fully formed talented and creative self living inside, but is a process of slowly freeing oneself from the confinement of abandonment depression in order to uncover a potential. It is a process of experimentation with the spontaneous, nonreactive elements that can be experienced in relationship with others.{{clarify|reason=what are these "spontaneous, nonreactive elements"?|date=November 2012}}

Working through abandonment depression is a complicated, lengthy and conflicted process that can be an enormously painful experience in terms of what is remembered and what must be felt. It involves mourning and grieving for the loss of the illusion that the patient had adequate support for the emergence of the real self. There is also a mourning for the loss of an identity, the false self, which the person constructed and with which he or she has negotiated much of his or her life. The dismantling of the false self requires relinquishing the only way that the patient has ever known of how to interact with others. This interaction was better than not to have a stable, organized experience of the self, no matter how false, defensive or destructive that identity may be.

The dismantling of the false self "leaves the impaired real self with the opportunity to convert its potential and its possibilities into actualities."<ref name="Klein6"/> Working through brings unique rewards, of which the most important element is the growing realization that the individual has a fundamental, internal need for relatedness that may be expressed in a variety of ways. "Only schizoid patients", suggests Klein, "who have worked through the abandonment depression&nbsp;... ultimately will believe that the capacity for relatedness and the wish for relatedness are woven into the structure of their beings, that they are truly part of who the patients are and what they contain as human beings. It is this sense that finally allows the schizoid patient to feel the most intimate sense of being connected with humanity more generally, and with another person more personally. For the schizoid patient, this degree of certainty is the most gratifying revelation, and a profound new organizer of the self experience."<ref name="Klein6"/>{{rp|127}}

==Development and course==
SzPD can be first apparent in childhood and adolescence with solitariness, poor peer relationships and underachievement in school. This may mark these children as different and make them subject to teasing.<ref name=":11" /><ref name=":8" />

Being a personality disorder, which are usually chronic and long-lasting mental conditions, SzPD is not expected to improve with time without treatment; however, much remains unknown because it is rarely encountered in clinical settings.<ref name="Medline" />

There has been an especially large contribution of people with schizoid symptoms to science and theoretical areas of knowledge, including maths, physics, economics, etc. At the same time, people with SzPD are helpless at many practical activities because of their symptoms.<ref>{{Cite book|url=https://books.google.com/books?id=Xw_JDgAAQBAJ&pg=PT215|title=Очерки душевной патологии. И возможности ее коррекции соотносительно с духовным измерением бытия|last=Белорусов|first=Сергей|date=2017-09-05|publisher=Litres|isbn=9785040548330|language=ru|quote=Especially important is the contribution of schizoid scientists in the theoretical fields of knowledge: mathematics, physics, economics. At the same time, schizoids are absolutely helpless in practical activities.}}</ref>

==Epidemiology==
SzPD is uncommon in clinical settings (about 2.2%) and occurs more commonly in males. It is rare compared with other personality disorders, with a prevalence estimated at less than 1% of the general population.<ref name="ClusterA" /><ref name=":9" /><ref name=":10">{{Cite journal|last1=Coid|first1=Jeremy|last2=Yang|first2=Min|last3=Tyrer|first3=Peter|last4=Roberts|first4=Amanda|last5=Ullrich|first5=Simone|date=May 2006|title=Prevalence and correlates of personality disorder in Great Britain|journal=The British Journal of Psychiatry: The Journal of Mental Science|volume=188|issue=5|pages=423–31|doi=10.1192/bjp.188.5.423 |pmid=16648528|doi-access=free}}</ref>

Philip Manfield suggests that the "schizoid condition", which roughly includes the DSM schizoid, avoidant and schizotypal personality disorders, is represented by "as many as forty percent of all personality disorders." Manfield adds "This huge discrepancy [from the ten percent reported by therapists for the condition] is probably largely because someone with a schizoid disorder is less likely to seek treatment than someone with other [[Diagnostic and Statistical Manual of Mental Disorders#DSM-IV multi-axial system|axis II]] disorders."<ref name=":0" /><ref>{{Cite journal|last=[[George Eman Vaillant]]|year=1985|title=Maturity of Ego Defenses in Relation to DSM-III Axis II Personality Disorder|journal=Archives of General Psychiatry|volume=42|issue=6|pages=597–601|doi=10.1001/archpsyc.1985.01790290079009|pmid=4004502}} Manfield backs his claim up with this study; it showed that of the seventy-four people inner city males found to have personality disorders, thirty were schizoid or avoidant.</ref>

A 2008 study assessing personality and mood disorder prevalence among [[homeless people]] at New York City [[drop-in centres]] reported an SzPD rate of 65% among this sample. The study did not assess homeless people who did not show up at drop-in centres, and the rates of most other personality and mood disorders within the drop-in centres was lower than that of SzPD. The authors noted the limitations of the study, including the higher male-to-female ratio in the sample and the absence of subjects outside the support system or receiving other support (e.g., [[Homeless shelter|shelters]]) as well as the absence of subjects in geographical settings outside New York City, a large city often considered a magnet for disenfranchised people.<ref>{{Cite journal|last=Connolly|first=Adrian J.|year=2008|title=Personality disorders in homeless drop-in center clients|url=http://www.ncsinc.org/images/pdfs/JPD_article_winter_2008.pdf|archive-url=https://web.archive.org/web/20090617134208/http://www.ncsinc.org/images/pdfs/JPD_article_winter_2008.pdf|url-status=dead|archive-date=2009-06-17|journal=Journal of Personality Disorders|volume=22|issue=6|pages=573–588|doi=10.1521/pedi.2008.22.6.573|pmid=19072678}}</ref>

A [[University of Colorado Colorado Springs]] study comparing personality disorders and [[Myers–Briggs Type Indicator]] types found that the disorder had a significant correlation with the Introverted (I) and Thinking (T) preferences.<ref>{{cite web|url=http://www.uccs.edu/Documents/dsegal/An-empirical-investigation-Jungs-types-and-PD-features-JPT-2.pdf|title=An Empirical Investigation of Jung's Personality Types and Psychological Disorder Features|publisher=Journal of Psychological Type/[[University of Colorado Colorado Springs]]|year=2001|access-date=August 10, 2013|archive-url=https://web.archive.org/web/20140125013714/http://www.uccs.edu/Documents/dsegal/An-empirical-investigation-Jungs-types-and-PD-features-JPT-2.pdf|archive-date=2014-01-25|url-status=live}}</ref>

==Criticism==
[[Nancy McWilliams]] of [[Rutgers University]] and Parpottas Panagiotis of [[European University Cyprus]] have argued that the definition of SzPD is flawed due to [[cultural bias]] and that it does not constitute a mental disorder but simply an [[Attachment in adults#Dismissive–avoidant|avoidant attachment style]] requiring more emotional distance.<ref>{{cite book|url=https://books.google.com/books?id=BzPOAWB2DncC&pg=PA196|title=Psychoanalytic Diagnosis: Understanding Personality Structure in the Clinical Process|last=Nancy McWilliams|date=2011|publisher=[[Guilford Press]]|isbn=9781609184940|edition=2nd|location=New York|page=196|author-link=Nancy McWilliams}}</ref><ref>{{cite journal|author=Parpottas Panagiotis|year=2012|title=A critique on the use of standard psychopathological classifications in understanding human distress: The example of 'Schizoid Personality Disorder'|url=https://psycnet.apa.org/record/2012-08620-004|journal=Counselling Psychology Review|volume=27|issue=1|pages=44–52}}</ref> If that is true, then many of the more problematic reactions these individuals show in social situations may be partly accounted for by the judgements commonly imposed on people with this style. However, impairment is mandatory for [[Personality disorder#DSM-5 general criteria|classification as a personality disorder]]. SzPD seems to satisfy this criterion because it is linked to negative outcomes, including reduced [[Global Assessment of Functioning|overall functioning]] even after 15 years and among the lowest levels of [[quality of life]] and "life success" for all personality disorders (measured as "status, wealth and successful relationships").<ref name=":9" /><ref name=":12" /><ref name=":7" /> However, determination of what qualify as "impairments" or as "negative outcomes" is itself potentially subject to cultural bias. People with SzPD may not regard a lack of social-status or successful relationships, for example, as a harm. Furthermore, correlation with negative outcomes does not necessarily demonstrate that these outcomes were directly caused by the schizoid traits. Rather, it may be that these outcomes are the result of discrimination against people with SzPD, who may be viewed as abnormal.

Due to the poor consistency and efficiency of diagnosis due to overlapping traits, it has been argued that SzPD should be removed altogether from the DSM.<ref name=":22" /> In 2012, an article called for the replacement of the SzPD category with a dimensional model which would allow for the description of schizoid traits on an individual basis,<ref name=":7" /> suggesting that two different disorders may better represent SzPD: one affect-constricted disorder (belonging to schizotypal PD, see also "emotional detachment" in 6D11.1 of {{section link|ICD-11#Personality disorder}}) and a seclusive disorder (belonging to avoidant PD, see also "social detachment" in 6D11.1 of {{section link|ICD-11#Personality disorder}}).

==Origin and historical definition==
The term "schizoid" was coined in 1908 by [[Eugen Bleuler]] to designate a human tendency to direct attention toward one's inner life and away from the external world as a concept akin to [[introversion]], not viewed in terms of psychopathology. Bleuler labeled the exaggeration of this tendency the "schizoid personality".<ref name="Akhtar"/> He described these personalities as "comfortably dull and at the same time sensitive, people who in a narrow manner pursue vague purposes".<ref name=":13">{{Cite journal|last1=Livesley|first1=W. J.|last2=West|first2=M.|date=February 1986|title=The DSM-III Distinction between schizoid and avoidant personality disorders|journal=Canadian Journal of Psychiatry|volume=31|issue=1|pages=59–62|doi=10.1177/070674378603100112|pmid=3948107|s2cid=46283956}}</ref>

In 1910, [[August Hoch]] introduced a very similar concept called the "shut-in" personality, characterised by reticence, seclusiveness, shyness and a preference for living in fantasy worlds, among others.<ref name=":13" /> In 1925, Russian psychiatrist [[Grunya Sukhareva]] described a "schizoid psychopathy" in a group of children, resembling today's SzPD and [[Autism spectrum|ASD]]. About a decade later [[Pyotr Gannushkin]] also included ''Schizoids'' and ''Dreamers'' in his detailed typology of personality types.<ref>Both types shared a detachment from the world but ''Schizoids'' also showed eccentricity and paradoxicality of emotional life and behavior, emotional coldness and dryness, unpredictability combined with lack of intuition and ambivalence (e.g., simultaneous presence of both stubbornness and submissiveness).
Characteristic of ''Dreamers'' were tenderness and fragility, receptiveness to beauty, weak-willedness and listlessness, luxuriant imagination, [[Glossary of psychiatry#Dereistic thinking|dereism]] and usually an inflated self-concept. ''(From: Gannushkin, P.B (1933). Manifestations of psychopathies: statics, dynamics, systematic aspects.)''</ref>

===Clinical studies===
Studies on the schizoid personality have developed along two distinct paths.

====Descriptive psychiatry tradition====
The [[descriptive psychiatry]] tradition focuses on overtly observable, behavioral and describable symptoms and finds its clearest exposition in the [[DSM-5]].

The descriptive psychiatry tradition began in 1925 with the description of observable schizoid behaviors by [[Ernst Kretschmer]]. He organized those into three groups of characteristics:<ref name=":6">{{Cite book|title=Physique and Character|last=Ernst Kretschmer|publisher=Routledge (International Library of Psychology,1999)|year=1931|isbn=978-0-415-21060-7|location=London|oclc = 858861653}}</ref>
# Unsociability, quietness, reservedness, seriousness and eccentricity.
# Timidity, shyness with feelings, sensitivity, nervousness, excitability, fondness of nature and books.
# Pliability, kindliness, honesty, indifference, silence and cold emotional attitudes.

These characteristics were the precursors of the [[DSM-III]] division of the schizoid character into three distinct personality disorders: [[Schizotypal personality disorder|schizotypal]], [[Avoidant personality disorder|avoidant]] and schizoid. Kretschmer himself, however, did not conceive of separating these behaviors to the point of radical isolation but considered them to be simultaneously present as varying potentials in schizoid individuals. For Kretschmer, the majority of schizoids are not ''either'' oversensitive ''or'' cold, but they are oversensitive and cold "at the same time" in quite different relative proportions, with a tendency to move along these dimensions from one behavior to the other.<ref name=":6" />

====Dynamic psychiatry tradition====
The [[dynamic psychiatry]] tradition includes the exploration of covert or unconscious motivations and [[character structure]] as elaborated by classic [[psychoanalysis]] and [[object-relations theory]].

The dynamic psychiatry tradition began in 1924 with observations by [[Eugen Bleuler]],<ref>Eugen Bleuler – ''Textbook of Psychiatry'', New York: Macmillan (1924)</ref> who observed that the schizoid person and schizoid pathology were not things to be set apart.<ref name="Klein6" />{{rp|p. 5}} [[Ronald Fairbairn]]'s seminal work on the schizoid personality, from which most of what is known today about schizoid phenomena is derived, was presented in 1940. Here, Fairbairn delineated four central schizoid themes:
# The need to regulate interpersonal distance as a central focus of concern.
# The ability to mobilize [[Self-preservation|self-preservative]] defenses and self-reliance.
# A pervasive tension between the anxiety-laden need for attachment and the defensive need for distance that manifests in observable behavior as ''indifference''.
# An overvaluation of the inner world at the expense of the outer world.<ref name="Klein6" />{{rp|p. 9}}

Following Fairbairn, the dynamic psychiatry tradition has continued to produce rich explorations on the schizoid character, most notably from writers Nannarello (1953),<ref name=":3"/> [[R. D. Laing|Laing]] (1965),<ref name="Laing1960" /> [[Donald Winnicott|Winnicott]] (1965),<ref>Donald Winnicott (1965): ''[https://books.google.com/books?id=WbGIEhINP6kC The Maturational Processes and the Facilitating Environment: Studies in the Theory of Emotional Development]''. Karnac Books. {{ISBN|9780946439843}}.</ref> [[Harry Guntrip|Guntrip]] (1969),<ref name=":4">{{Cite book|url=https://books.google.com/books?id=NFthUnBVwNEC|title=Schizoid Phenomena, Object-Relations, and The Self|last=Harry Guntrip|publisher=International Universities Press|year=1969|isbn=978-1-85575-032-6|location=New York}}</ref> [[Masud Khan|Khan]] (1974),<ref name=":1" /> [[Salman Akhtar|Akhtar]] (1987),<ref name="Akhtar" /> Seinfeld (1991),<ref name=":2" /> Manfield (1992)<ref name=":0" /> and Klein (1995).<ref name="Klein6" />

===Controversy===
The original concept of the schizoid character developed by Kretschmer in the 1920s comprised an amalgamation of [[Avoidant personality disorder|avoidant]], [[Schizotypal personality disorder|schizotypal]] and schizoid traits. The work of Millon in the 1980s led to this concept being split into three distinct disorders. This caused debate about whether this was accurate or if these traits were different expressions of a single personality disorder.<ref name=":13" />


==See also==
{{Portal|Psychology}}
{{div col|colwidth=30em}}
* [[Asociality]]
* [[Asociality]]
* [[Counterphobic attitude]]
* [[Counterphobic attitude]]
* [[Dissociation (psychology)]]
* [[Dissociation (psychology)]]
* [[Distrust]]
* [[Hermit]]
* [[Hermit]]
* [[Hikikomori]]
* [[Recluse]]
* [[Recluse]]
* [[Schizothymia]]
* [[Schizothymia]]
* [[Schizotypy]]
* [[Schizotypy]]
* [[Sluggish cognitive tempo]]
* [[Sluggish cognitive tempo]]
* [[Social alienation]]
* [[Social isolation]]
{{div col end}}


== References ==
== References ==
{{Reflist|30em}}
{{Reflist}}


== External links ==
== External links ==
{{sisterlinks|wikt=Schizoid personality disorder|c=Category:Schizoid personality disorder|n=no|q=no|s=no|b=Textbook of Psychiatry/Personality Disorders|v=no|d=Q498237}}
{{Medical resources
| ICD10 = {{ICD10|F|60|1|f|60}}
| ICD9 = {{ICD9|301.20}}
| MedlinePlus = 000920
| MeshID = D012557
| SNOMED CT = 52954000
}}
* [https://web.archive.org/web/20130531220453/http://www.points-and-positions.de/e107_files/downloads/The%20Biological%20Foundations%20of%20the%20Schizoid%20Process.pdf The biological foundations of the schizoid process]
* {{citation|author=Richard A. Friedman, M.D.|date=November 21, 2006|url=https://www.nytimes.com/2006/11/21/health/psychology/21case.html?ex=1321765200&en=6030af72aae03e77&ei=5088partner=rssnyt&emc=rss|website=The New York Times|title=Like a Fish Needs a Bicycle: For Some People, Intimacy Is Toxic}}
* {{citation|website=Psychology Today|date=January 2, 2017|author=Daniel J Winarick Ph.D.|url=https://www.psychologytoday.com/blog/personality-quotient/201701/the-disappearance-the-schizoid-personality|title=The Disappearance of the Schizoid Personality}}


* [https://web.archive.org/web/20130531220453/http://www.points-and-positions.de/e107_files/downloads/The%20Biological%20Foundations%20of%20the%20Schizoid%20Process.pdf The Biological foundations of the Schizoid Process]
{{ICD-10 personality disorders}}

* [https://web.archive.org/web/20210730021704/https://www.nytimes.com/2006/11/21/health/psychology/21case.html?ex=1321765200&en=6030af72aae03e77&ei=5088partner=rssnyt&emc=rss NY Times article "Like a Fish Needs a Bicycle: For Some People, Intimacy Is Toxic"]
* [[Psychology Today|''Psychology Today'']] (2017): [https://www.psychologytoday.com/blog/personality-quotient/201701/the-disappearance-the-schizoid-personality The Disappearance of the Schizoid Personality]{{Medical resources|ICD10={{ICD10|F|60|1|f|60}}|ICD9={{ICD9|301.20}}|MedlinePlus=000920|MeshID=D012557|SNOMED CT=52954000}}{{ICD-10 personality disorders}}
{{Authority control}}
{{Authority control}}
[[Category:Cluster A personality disorders|Cluster A personality disorders]]

[[Category:Cluster A personality disorders]]
[[Category:Schizophrenia|Schizophrenia]]
[[Category:Schizophrenia]]
[[Category:Personality disorders|Personality disorders]]

Revision as of 15:19, 16 January 2023

Schizoid personality disorder
Man sitting alone on a bench
People with schizoid personality disorder often prefer solitary activities.
Pronunciation
SpecialtyPsychiatry, clinical psychology
SymptomsPervasive emotional detachment, reduced affect, lack of close friends, apathy, anhedonia, unintentional insensitivity to social norms, sexual abstinence, preoccupation with fantasy,[1] autistic thinking without loss of skill to recognize reality[2]
Usual onsetLate childhood or adolescence[1]
DurationLife long
TypesLanguid schizoid, remote schizoid, depersonalized schizoid, affectless schizoid (Millon's subtypes)</ref>
CausesFamily history; cold, indifferent, or intrusive parenting; traumatic brain injury; low birth weight; prenatal malnutrition
Risk factorsFamily history[3]
Diagnostic methodBased on symptoms
Differential diagnosisOther mental disorders with psychotic symptoms (schizophrenia, delusional disorder, and a bipolar or depressive disorder with psychotic features), personality change due to another medical condition, substance use disorders, autism spectrum disorder, other personality disorders and personality traits
TreatmentPsychodynamic psychotherapy; Cognitive Behavioral Therapy
MedicationNot general practice but may include low dose benzodiazepines, β-blockers, nefazodone, bupropion[4]
PrognosisTypically poor[5][6][7]
Frequency0.8%[3][5][8]

Schizoid personality disorder (/ˈskɪtsɔɪd, ˈskɪdzɔɪd, ˈskɪzɔɪd/, often abbreviated as SzPD or ScPD) is a personality disorder characterized by a lack of interest in social relationships,[9] a tendency toward a solitary or sheltered li

fe style, secretiveness, emotional coldness, detachment, and apathy. Affected individuals may be unable to form intimate attachments to others and simultaneously possess a rich and elaborate but exclusively internal fantasy world.[10][11] Other associated features include stilted speech, a lack of deriving enjoyment from most activities, feeling as though one is an "observer" rather than a participant in life, an inability to tolerate emotional expectations of others, apparent indifference when praised or criticized, a degree of asexuality, and idiosyncratic moral or political beliefs.[12] Symptoms typically start in late childhood or adolescence.[10] The cause of SzPD is uncertain, but there is some evidence of links and shared genetic risk between SzPD, other cluster A personality disorders, and schizophrenia.[13][14][15][16][17] Thus, SzPD is considered to be a "schizophrenia-like personality disorder".[3][18] It is diagnosed by clinical observation, and it can be very difficult to distinguish SzPD from other mental disorders or conditions (such as autism spectrum disorder, with which it may sometimes overlap).[19][20]

The effectiveness of psychotherapeutic and pharmacological treatments for the disorder has yet to be empirically and systematically investigated. This is largely because people with SzPD rarely seek treatment for their condition.[10] Originally, low doses of atypical antipsychotics were also used to treat some symptoms of SzPD, but their use is no longer recommended.[21] The substituted amphetamine bupropion may be used to treat associated anhedonia.[4] However, it is not general practice to treat SzPD with medications, other than for the short-term treatment of acute co-occurring disorders (e.g. depression).[22] Talk therapies such as cognitive behavioral therapy (CBT) may not be effective, because people with SzPD may have a hard time forming a good working relationship with a therapist.[10]

SzPD is a poorly studied disorder, and there is little clinical data on SzPD because it is rarely encountered in clinical settings. Studies have generally reported a prevalence of less than 1%.[3][8][23] It is more commonly diagnosed in males than in females.[8] SzPD is linked to negative outcomes, including a significantly compromised quality of life, reduced overall functioning even after 15 years, and one of the lowest levels of "life success" of all personality disorders (measured as "status, wealth and successful relationships").[5][24][25] Bullying is particularly common towards schizoid individuals.[26][27] Suicide may be a running mental theme for schizoid individuals, though they are not likely to attempt it.[28] Some symptoms of SzPD (e.g. solitary lifestyle, emotional detachment, loneliness, and impaired communication), however, have been stated as general risk factors for serious suicidal behavior.[29][30]

History

The term "Schizoid" was coined in 1908 by Eugen Bleuler to describe a human tendency to direct attention toward one's inner life and away from the external world. Bleuler labeled the exaggeration of this tendency the "schizoid personality". He described these personalities as "comfortably dull and at the same time sensitive, people who in a narrow manner pursue vague purposes".[31] In 1910, August Hoch introduced a very similar concept called the "shut-in" personality. Characteristics of it were reticence, reclusiveness, shyness and a preference for living in fantasy worlds, among others. In 1925, Russian psychiatrist Grunya Sukhareva described a "schizoid psychopathy" in a group of children, resembling today's SzPD and ASD. About a decade later Pyotr Gannushkin also included Schizoids and Dreamers in his detailed typology of personality types[32].

The descriptive tradition began in 1925 with the description of observable schizoid behaviors by Ernst Kretschmer. He organized those into three groups of characteristics:[33]

  1. Unsociability, quietness, reservedness, seriousness and eccentricity.
  2. Timidity, shyness with feelings, sensitivity, nervousness, excitability, fondness of nature and books.
  3. Pliability, kindliness, honesty, indifference, silence and cold emotional attitudes.[33]

These characteristics were the precursors of the DSM-III division of the schizoid character into three distinct personality disorders: schizotypal, avoidant and schizoid. Kretschmer himself, however, did not conceive of separating these behaviors to the point of radical isolation but considered them to be simultaneously present as varying potentials in schizoid individuals. For Kretschmer, the majority of schizoids are not either oversensitive or cold, but they are oversensitive and cold "at the same time" in quite different relative proportions, with a tendency to move along these dimensions from one behavior to the other.[33]

The second path, that of dynamic psychiatry, began in 1924 with observations by Eugen Bleuler, who observed that the schizoid person and schizoid pathology were not things to be set apart. Ronald Fairbairn's seminal work on the schizoid personality, from which most of what is known today about schizoid phenomena is derived, was presented in 1940. Here, Fairbairn delineated four central schizoid themes:,[34] who observed that the schizoid person and schizoid pathology were not things to be set apart.

  1. The need to regulate interpersonal distance as a central focus of concern.
  2. The ability to mobilize self-preservative defenses and self-reliance.
  3. A pervasive tension between the anxiety-laden need for attachment and the defensive need for distance that manifests in observable behavior as indifference.
  4. An overvaluation of the inner world at the expense of the outer world.

Following Fairbairn, the dynamic psychiatry tradition has continued to produce rich explorations on the schizoid character, most notably from writers Nannarello (1953), Laing (1965), Winnicott (1965),[35] Guntrip (1969), Khan (1974), Akhtar (1987), Seinfeld (1991), Manfield (1992) and Klein (1995).

The DSM-I had the diagnosis of Schizoid personality which was defined by avoidance of close relationships, inability to express aggressive feelings, and autistic thinking.[36] The DSM-II later updated the definition to include daydreaming, detachment from reality, and sensitivity.[37] It was incorporated into the DSM-III as Schizoid personality disorder to describe difficulties forming meaningful social relationships and a persistent pattern of disconnection and apathy.[38][39] The diagnosis of SzPD made it to the DSM-IV and DSM-V.[40]

Epidemiology

It is also unclear how prevalent the disorder is, although it may be present in anywhere from 0.5% to 7% of the population. Possibly even 14% of the homeless population.[41] Gender differences in this disorder are also unclear.[38][42] Some research has suggested that men may have this disorder more frequently in men than women.[43][44][45] SzPD is uncommon in clinical settings (about 2.2%) and occurs more commonly in males. It is rare compared with other personality disorders.[46][47][48] Philip Manfield suggests that the "schizoid condition", which roughly includes the DSM schizoid, avoidant and schizotypal personality disorders, is represented by "as many as forty percent of all personality disorders." Manfield adds "This huge discrepancy [from the ten percent reported by therapists for the condition] is probably largely because someone with a schizoid disorder is less likely to seek treatment than someone with other axis-II disorders."[49][50] A 2008 study assessing personality and mood disorder prevalence among homeless people at New York City drop-in centers reported an SzPD rate of 65% among this sample. The study did not assess homeless people who did not show up at drop-in centers, and the rates of most other personality and mood disorders within the drop-in centers were lower than that of SzPD. The authors noted the limitations of the study, including the higher male-to-female ratio in the sample and the absence of subjects outside the support system or receiving other support (e.g., shelters) as well as the absence of subjects in geographical settings outside New York City, a large city often considered a magnet for disenfranchised people.[51] A University of Colorado Colorado Springs study comparing personality disorders and Myers–Briggs Type Indicator types found that the disorder had a significant correlation with the Introverted (I) and Thinking (T) preferences.[52]

Etiology

Environmental

Perfectionist and hypercritical parenting or cold,[53] neglectful, and distant parenting contribute to the onset of SzPD.[41][43][54] For a person with SzPD, their parents likely were intolerant of their emotional experiences.[55] They may have been forced to repress and compartmentalize their emotions, possibly resulting in the onset of difficulties expressing and processing emotional experiences.[56] These difficulties lead to the child feeling rejected and developing the belief that the only safe environment is one where they are alone and inexpressive.[57][58][59][60] People with SzPD may also have internalized the belief that their emotions are dangerous to themselves and others due to the negative responses received from others.[61][62][63] In their status of isolation and emotional bluntness they can be self-sufficient and safe.[64][65] Childhood trauma can also contribute to feelings of emptiness in adulthood.[66] Alcoholism in parents is associated with a heightened risk of developing SzPD.[67]

Genetic

Sula Wolff, who did extensive research and clinical work with children and teenagers with schizoid symptoms, stated that "schizoid personality has a constitutional, probably genetic, basis."[68] Research on heritability and this disorder is lacking.[38] Twin studies with SzPD traits (e.g. low sociability and low warmth) suggest these are inherited. Besides this indirect evidence, the direct heritability estimates of SzPD range from 50 to 59%.[69][70] Other research has found the heritability rate to be 29%.[71] Researchers are also unsure of the pathophysiology of SzPD. Genetic relationships with people who have Schizophrenia spectrum disorders increase the risk of developing Schizoid Personality Disorder.[72][73][74][75] People with SzPD can have a history of schizotypy before developing the disorder.[76][77][78][79] SzPD symptoms can be premorbid to Schizophrenia.[80][81][82][83][84][85]

Neurological

Prenatal malnutrition,[86][87] premature birth, and low birth weight are all thought to play a role in the development of SzPD.[88][89][90][91] SzPD is associated with reduced serotonergic and dopaminergic pathways in areas such as the frontal lobe, amygdala, and striatum.[92][93][94][95] Traumatic brain injuries to the frontal lobe may also contribute to the onset of SzPD as that area of the brain controls areas such as emotion and socialization.[96][66][97] Deficits in the right hemisphere of the brain may also be associated with SzPD.[98] Lower levels of low-density lipoprotein cholesterol may be correlated with the presence of Schizoid traits in women.[99] Excess indices in the left hemisphere may also be related to SzPD.[100]

Prognosis

Traits of Schizoid Personality Disorder appear in childhood and adolescence. Children with this disorder usually have poor relationships with others,[101][102] social anxiety, internal fantasies, strange behavior, and hyperactivity. These behaviors usually result in teasing and bullying at the hands of others.[103][104] It is common for people with SzPD to have had Major Depressive Disorder in childhood.[48][105] SzPD is associated with lower levels of achievement and a compromised quality of life.[48][106] The presence of Schizoid symptoms is also associated with a worse outcome of treatment.[107] Treatment for this disorder is understudied and poorly understood.[108] There is no widely accepted and approved psychotherapy or medication for this disorder. It is one of the most poorly researched psychiatric disorders.[93] Professionals may misunderstand the disorder and the client, potentially reinforcing a feeling of failure, and negatively impacting their willingness to continue to commit to treatment.[90] Clinicians also tend to worry that they are incapable of properly treating the patient.[109] It is rare for someone with this disorder to voluntarily seek treatment without a comorbid disorder or pressure from family or friends.[110] In treatment, people with SzPD are usually disinterested and often minimize symptoms. Patients with SzPD may also fear losing their independence through therapy. Many schizoids will also avoid making the efforts required to establish a proper relationship with the therapist. It can also be difficult for them to open up or discuss their emotions in therapy.[60] Although people with this disorder can still improve, it is unlikely they will ever experience significant joy through social interaction.[38]

Signs and symptoms

Social Isolation

People with SzPD are often socially isolated

SzPD is associated with a dismissive-avoidant attachment style.[60][111][112][113] People with this disorder will rarely maintain close relationships and often exclusively choose to participate in solitary activities.[114][115][116] People with Schizoid Personality disorder typically have no close friends or confidants, except for a close relative on occasions. They usually prefer hobbies and activities that do not require interaction with others.[117][118] People with SzPD may be averse to social situations due to difficulties deriving pleasure from physical or emotional sensations, rather than social anhedonia.[119][120] One potential motivation for avoiding social situations is that they can intrude on their freedom.[66][121] Relationships can feel suffocating for people with SzPD,[122] and they may think of them as opportunities for entrapment.[47][123] Patients with this disorder are often independent and turn to themselves as sources of validation. They tend to be the happiest when in relationships in which their partner places few emotional or intimate demands on them and does not expect phatic or social niceties. It is not necessarily people they want to avoid, but negative or positive emotional expectations, emotional intimacy, and self-disclosure.[90][124] Patients with SzPD can feel as if close emotional bonds can be dangerous to themselves and others.[62][121][125] They may also have feelings of inadequacy or shame.[126] Some people with SzPD may experience a deep desire to connect with others, but will also be terrified by the danger doing so can invoke.[121][127] Avoidance of social situations may be a method of avoiding being hurt or rejected.[128][129] Individuals with SzPD can form relationships with others based on intellectual, physical, familial, occupational, or recreational activities, as long as there is no need for emotional intimacy Donald Winnicott explains this is because schizoid individuals "prefer to make relationships on their own terms and not in terms of the impulses of other people." Failing to attain that, they prefer isolation.[130] In general, friendship among schizoids is usually limited to one person, often also schizoid, forming what has been called a union of two eccentrics; "within it – the ecstatic cult of personality, outside it – everything is sharply rejected and despised".[131] Their unique lifestyle can lead to social rejection and people with SzPD are at a higher risk of facing bullying or homelessness.[132][133] This social rejection can reinforce their asocial behavior.

Sexuality

People with this disorder usually have little interest in sexual or romantic acts. They rarely date or marry.[134][135][136] Sex often causes individuals with SzPD to feel that their personal space is being violated, and they commonly feel that masturbation or sexual abstinence is preferable to the emotional closeness they must tolerate when having sex.[137] Significantly broadening this picture are notable exceptions of SzPD individuals who engage in occasional or even frequent sexual activities with others.[137] Individuals with SzPD have long been noted to have an increased rate of unconventional sexual tendencies, though if present, these are rarely acted upon. The schizoid is often labeled asexual or presents with "a lack of sexual identity". Kernberg states that this apparent lack of sexuality does not represent a lack of sexual definition but rather a combination of several strong fixations to cope with the same conflicts. People with SzPD are often able to pursue any fantasies with content on the Internet while remaining completely unengaged with the outside world.[60]

Emotions

Sensory or emotional experiences typically provide little enjoyment for people with SzPD.[138][139] They rarely display strong emotions or react to anything.[140] People with SzPD can have difficulty expressing themselves and seem to be directionless or passive.[41] Individuals with SzPD can also experience anhedonia.[141] They can also have difficulty understanding others' emotions and social cues.[142][143][144] It can be hard for people with SzPD to assess the impact of their actions in social situations.[145][146] People with this condition are often indifferent towards criticism or praise and can appear distant, aloof, or uncaring to others.[147] They may avoid others and expressing themselves as a method of keeping others distant and preventing themselves from being hurt.[148][58][128] Remaining alone and expressionless can feel safe and comfortable for people with SzPD.[149] Expressing themselves can make them feel uncomfortable and afraid of failure or shame.[41] People with SzPD may feel inadequate and can be sensitive,[150] although they have difficulty expressing it.[151][60] Alexithymia, or difficulties understanding one's own emotions is common amongst people with SzPD.[152][153][154] This leads to them isolating themselves to avoid the discomfort and stimulation emotional experiences offer.[60] According to Guntrip, Klein, and others, people with SzPD may possess a hidden sense of superiority and lack dependence on other people's opinions. This is very different from the grandiosity seen in narcissistic personality disorder, which is described as "burdened with envy" and with a desire to destroy or put down others. Additionally, schizoids do not go out of their way to achieve social validation. Unlike the narcissist, the schizoid will often keep their creations private to avoid unwelcome attention or the feeling that their ideas and thoughts are being appropriated by the public.[60] When forced to rely on others a person with SzPD may feel panic or terror.[60]

It is common for people with SzPD to experience depersonalization

Feelings of unreality

Patients with SzPD often feel unreal, empty,[90][127] and that they are separate from their own emotions.[155] They tend to perceive themselves as fundamentally different from others and can believe themselves to be fundamentally unlikeable.[121][156] Other people often seem strange and incomprehensible to a person with SzPD. Reality can feel unenjoyable and uninteresting to people with SzPD. They have difficulty finding motivation and lack ambition.[157][158][159] Patients with SzPD often feel as if they are "going through the motions" or that "life passes them by."[6][160][161] Many describe feeling as if they are observing life from a distance.[162] Aaron Beck and his colleagues report that people with SzPD seem comfortable with their aloof lifestyle and consider themselves observers, rather than participants in the world around them. But they also mention that many of their schizoid patients recognize themselves as socially deviant (or even defective) when confronted with the different lives of ordinary people – especially when they read books or see movies focusing on relationships. Even when schizoid individuals may not long for closeness, they can become weary of being "on the outside, looking in". These feelings may lead to depression, depersonalization, or derealization.[121][6][60] If they do, schizoid people often experience feeling "like a robot" or "going through life in a dream".[163] People with SzPD may try to avoid all physical activity in order to become nobody and disconnect from reality. This can lead to the patient spending a large quantity of time sleeping and ignoring bodily functions such as hygiene.[60] For people with SzPD,

Internal fantasy

Although this disorder does not affect the patient's capacity to understand reality, they may engage in excessive daydreaming and introspection.[43][164][165] Their daydreams can grow to consume most of their lives. Real life can become secondary to their fantasy,[7] and they can have complex lives and relationships which exist entirely inside of their internal fantasy. These daydreams may a defense mechanism to protect the patient from the outside world and its difficulties.[62][121][166] Common themes in their internal fantasies are omnipotence and grandiosity.[60] The related schizotypal personality disorder and schizophrenia are reported to have ties to creative thinking, and it is speculated that the internal fantasy aspect of SzPD may also be reflective of this thinking.[167][168][169] Alternatively, there has been an especially large contribution of people with schizoid symptoms to science and theoretical areas of knowledge, including mathematics, physics, economics, etc. At the same time, people with SzPD are helpless at many practical activities because of their symptoms.[170]

Suicide and Self-harm

Symptoms of SzPD such as isolation and the blunted affect put people with Schizoid Personality disorder at a higher risk of suicide and non-suicidal self-harm.[171][172][173] This may be because their reduced capacities for emotion prevent them from properly dealing with strife. Their solitary nature may also contribute by preventing them from finding relief in relationships.[174] Demonstrative suicides or suicide blackmail, as seen in cluster B personality disorders such as borderline, histrionic, or antisocial, are extremely rare among schizoid individuals.[175] As in other clinical mental health settings, among suicidal inpatients, individuals with SzPD are not as well-represented as some other groups. A 2011 study on suicidal inpatients at a Moscow hospital found that schizoids were the least common patients, while those with cluster B personality disorders were the most common.[175]

Low weight

A study that looked at the body mass index (BMI) of a sample of both male adolescents diagnosed with SzPD and those diagnosed with Asperger syndrome found that the BMI of all patients was significantly below normal. Clinical records indicated abnormal eating behavior by some patients. Some patients would only eat when alone and refused to eat out. Restrictive diets and fears of disease were also found. It was suggested that the anhedonia of SzPD may also cover eating, leading schizoid individuals to not enjoy it.[176] Alternatively, it was suggested that schizoid individuals may not feel hunger as strongly as others or not respond to it, a certain withdrawal "from themselves".[88]

Substance abuse

Very little data exists for rates of substance use disorder among people with SzPD, but existing studies suggest they are less likely to have substance abuse problems than the general population. One study found that significantly fewer boys with SzPD had alcohol problems than a control group of non-schizoids.[177] Another study evaluating personality disorder profiles in substance abusers found that substance abusers who showed schizoid symptoms were more likely to abuse one substance rather than many, in contrast to other personality disorders such as borderline, antisocial, or histrionic, which were more likely to abuse many.[178] American psychotherapist Sharon Ekleberry states that the impoverished social connections experienced by people with SzPD limit their exposure to the drug culture and that they have limited inclination to learn how to do illegal drugs. Describing them as "highly resistant to influence", she additionally states that even if they could access illegal drugs, they would be disinclined to use them in public or social settings, and because they would be more likely to use alcohol or cannabis alone than for social disinhibition, they would not be particularly vulnerable to negative consequences in early use.[179] Other studies have found that they have a higher risk of developing substance abuse issues than normal people.[180][181][182] Despite this, people with SzPD are at a lower risk of substance abuse issues than other Personality disorders.[183][184] They may form relationships with their substances as a substitute for human contact or to cope with emotional issues.[185][186] People with SzPD may desire psychedelic drugs more than other kinds.[187]

Secret Schizoids

Many schizoid individuals display an engaging, interactive personality, contradicting the observable characteristic emphasized by the DSM-5 and ICD-10 definitions of the schizoid personality. Guntrip (using ideas of Klein, Fairbairn, and Winnicott) classifies these individuals as "secret schizoids", who behave with socially available, interested, engaged, and involved interaction yet remain emotionally withdrawn and sequestered within the safety of the internal world.[188][189] Klein distinguishes between a "classic" SzPD and a "secret" SzPD, which occur "just as often" as each other. Klein cautions one should not misidentify the schizoid person as a result of the patient's defensive, compensatory interaction with the external world. He suggests one ask the person what their subjective experience is, to detect the presence of the schizoid refusal of emotional intimacy and preference for objective fact.[188] A 2013 study looking at personality disorders and Internet use found that being online more hours per day predicted signs of SzPD. Additionally, SzPD correlated with lower phone call use and fewer Facebook friends.[190]

Descriptions of the schizoid personality as "hidden" behind an outward appearance of emotional engagement have been recognized since 1940, with Fairbairn's description of "schizoid exhibitionism", in which the schizoid individual can express a great deal of feeling and make what appear to be impressive social contacts yet, in reality, gives nothing and loses nothing. Because they are "playing a part", their personality is not involved. According to Fairbairn, the person disowns the part they are playing, and the schizoid individual seeks to preserve their personality intact and immune from compromise.[191] The schizoid's false persona is based on what those around them define as normal or good behavior, as a form of compliance.[60] Further references to the secret schizoid come from Masud Khan,[192] Jeffrey Seinfeld,[193] and Philip Manfield.[50] These scholars described secret schizoids as people who enjoy public speaking engagements but experience great difficulty during the breaks when audience members would attempt to engage them emotionally. These references expose the problems in relying on outer observable behavior for assessing the presence of personality disorders in certain individuals.

Comorbid Disorders

Asperger's Syndrome

Several studies have reported an overlap or comorbidity with the autism spectrum disorder Asperger syndrome.[197][198][88][199][200][201] Asperger syndrome had traditionally been called "schizoid disorder of childhood",[202][203][204] and Eugen Bleuler coined both the terms "autism" and "schizoid" to describe withdrawal to an internal fantasy, against which any influence from outside becomes an intolerable disturbance.[205] In a 2012 study of a sample of 54 young adults with Asperger syndrome, it was found that 26% of them also met the criteria for SzPD, the highest comorbidity out of any personality disorder in the sample (the other comorbidities were 19% for obsessive–compulsive personality disorder, 13% for avoidant personality disorder and one female with schizotypal personality disorder). Additionally, twice as many men with Asperger syndrome met the criteria for SzPD than women. While 41% of the whole sample were unemployed with no occupation, this rose to 62% for the Asperger's and SzPD comorbid group.[197] Tantam suggested that Asperger syndrome may confer an increased risk of developing SzPD.[88] A 2019 study found that 54% of a group of males aged 11 to 25 with Asperger syndrome showed significant SzPD traits, with 6% meeting full diagnostic criteria for SzPD, compared to 0% of a control group.[198]

In the 2012 study, it was noted that the DSM may complicate diagnosis by requiring the exclusion of a pervasive developmental disorder (PDD) before establishing a diagnosis of SzPD. The study found that social interaction impairments, stereotyped behaviors, and specific interests were more severe in the individuals with Asperger syndrome also fulfilling SzPD criteria, against the notion that social interaction skills are unimpaired in SzPD. The authors believe that a substantial subgroup of people with autism spectrum disorder or PDD have clear "schizoid traits" and correspond largely to the "loners" in Lorna Wing's classification The autism spectrum (Lancet 1997), described by Sula Wolff.[197] The authors of the 2019 study hypothesized that it is extremely likely that historic cohorts of adults diagnosed with SzPD either also had childhood-onset autistic syndromes or were misdiagnosed. They stressed that further research to clarify overlap and distinctions between these two syndromes was strongly warranted, especially given that high-functioning autism spectrum disorders are now recognized in around 1% of the population.[206]

Treatment

Medication

There are no effective medications for Schizoid Personality Disorder. However, certain medications may reduce the symptoms of SzPD as well as treat co-occurring mental disorders. Since the symptoms of SzPD mirror the negative symptoms of schizophrenia, antipsychotics have been suggested as a potentially effective medication for SzPD.[207][7][208][209] Originally, low doses of atypical antipsychotics like risperidone or olanzapine were used to alleviate social deficits and blunted affect.[210][211][212][213] However, a 2012 review concluded that atypical antipsychotics were ineffective for treating personality disorders.[151] Antidepressants,[90] SSRIs,[214] anxiolitics,[60] bupropion,[212] modafinil,[215] benzodiazepines,[216][217] electrocardiography, and biofeedback may also be effective treatments.[218]

Basic tenets of Cognitive-Behavioral Therapy, a kind of Psychotherapy used to treat SzPD

Psychotherapy

Treatment for this disorder uses a combination of Cognitive-behavioral therapy and Psychodynamic psychotherapy.[90][219][220] These techniques can be used to help the patient identify their defense mechanisms and change them.[47][221][222] Therapists also attempt to establish a healthy relationship with the client with SzPD.[223] This can help combat their internalized belief that relationships are harmful and unhelpful. Relationships with a therapist can seem terrifying and intrusive to a person with SzPD.[224][225] They may feel as if they need to alter or hide their feelings to meet the therapist's demands or expectations. To combat this, therapists try to gradually increase their patient's emotional expression. Expressing too much too early can lead to them ending therapy. Treatment for a person with SzPD must be person-centered, with the client feeling understood and well-regarded.[128][226][227] This can allow the patient to connect with and understand their emotions.[228][229][230] If a person with SzPD does not have their feelings validated or has their emotions confronted, this will confirm their belief that expressing themselves is dangerous.[60] Therapists also attempt to avoid intruding on the patient with SzPD's life or restricting their freedoms,[60] as this can make the patient feel as if therapy is intolerable.[6] Because of this, therapy for people with SzPD is usually less structured then treatment programs for other disorders.[60]Patients with SzPD may benefit from long-term treatment lasting several years.[231][151] Inpatient care may also be an effective way of treating SzPD and other Cluster A disorders.[232]

Controversy

The original concept of the schizoid character developed by Ernst Kretschmer in the 1920s comprised an amalgamation of avoidant, schizotypal, and schizoid traits. It was not until 1980 and the work of Theodore Millon that led to splitting this concept into three personality disorders (now schizoid, schizotypal, and avoidant). This caused debate about whether this was accurate or if these traits were different expressions of a single personality disorder.[31] It has also been argued due to the poor consistency and efficiency of diagnosis due to overlapping traits that SzPD should be removed altogether from the DSM.[199]

A 2012 article suggested that two different disorders may better represent SzPD: one affect-constricted disorder (belonging to schizotypal PD) and a seclusive disorder (belonging to avoidant PD). They called for the replacement of the SzPD category from future editions of the DSM with a dimensional model which would allow for the description of schizoid traits on an individual basis.[48]

Some critics such as Nancy McWilliams of Rutgers University and Parpottas Panagiotis of European University Cyprus argue that the definition of SzPD is flawed due to cultural bias and that it does not constitute a mental disorder but simply an avoidant attachment style requiring a more distant emotional proximity.[128][233] If that is true, then many of the more problematic reactions these individuals show in social situations may be partly accounted for by the judgments commonly imposed on people with this style. However, impairment is mandatory for any behavior to be diagnosed as a personality disorder. SzPD seems to satisfy this criterion because it is linked to negative outcomes. These include a significantly compromised quality of life, reduced overall functioning even after 15 years, and one of the lowest levels of "life success" of all personality disorders (measured as "status, wealth and successful relationships").[48][47][234] However, the determination of what qualifies as "impairments" or as "negative outcomes" is itself potentially subject to cultural bias. People with SzPD may not regard a lack of social status or successful relationships, for example, as harm. Furthermore, correlation with negative outcomes does not necessarily demonstrate that these outcomes were directly caused by schizoid traits. Rather, it may be that these outcomes are the result of discrimination against people with SzPD, who may be viewed as abnormal.

Diagnosis

Guntrip criteria

Ralph Klein, Clinical Director of the Masterson Institute, delineates the following nine characteristics of the schizoid personality as described by Harry Guntrip:[235]: 13–23 

The description of Guntrip's nine characteristics should clarify some differences between the traditional DSM portrait of SzPD and the traditional informed object relations view. All nine characteristics are consistent. Most, if not all, must be present to diagnose a schizoid disorder.[235]

Millon's subtypes

Theodore Millon restricted the term "schizoid" to those personalities who lack the capacity to form social relationships. He characterizes their way of thinking as being vague and void of thoughts and as sometimes having a "defective perceptual scanning". Because they often do not perceive cues that trigger affective responses, they experience fewer emotional reactions.[236][237]

For Millon, SzPD is distinguished from other personality disorders in that it is "the personality disorder that lacks a personality." He criticizes that this may be due to the current diagnostic criteria: They describe SzPD only by an absence of certain traits, which results in a "deficit syndrome" or "vacuum". Instead of delineating the presence of something, they mention solely what is lacking. Therefore, it is hard to describe and research such a concept.[238]

He identified four subtypes of SzPD. Any individual schizoid may exhibit none or one of the following:[238][239]

Subtype Features
Languid schizoid (including dependent and depressive features) Marked inertia; deficient activation level; intrinsically phlegmatic, lethargic, weary, leaden, lackadaisical, exhausted, enfeebled. Unable to act with spontaneity or seeks simplest pleasures, may experience profound angst, yet lack the vitality to express it strongly.
Remote schizoid (including avoidant features) Distant and removed; inaccessible, solitary, isolated, homeless, disconnected, secluded, aimlessly drifting; peripherally occupied. Seen among people who would have been otherwise capable of developing normal emotional life but having been subjected to intense hostility lost their innate capability to form bonds. Some residual anxiety is present.
Depersonalized schizoid (including schizotypal features) Disengaged from others and self; self is disembodied or distant object; body and mind sundered, cleaved, dissociated, disjoined, eliminated. Often seen as simply staring into the empty space or being occupied with something substantial while actually being occupied with nothing at all.
Affectless schizoid (including compulsive features) Passionless, unresponsive, unaffectionate, chilly, uncaring, unstirred, spiritless, lackluster, unexcitable, unperturbed, cold; all emotions diminished. Combines the preference for rigid schedule (obsessive-compulsive feature) with the coldness of the schizoid.

Akhtar's profile

American psychoanalyst Salman Akhtar provided a comprehensive phenomenological profile of SzPD in which classic and contemporary descriptive views are synthesized with psychoanalytic observations. This profile is summarized in the table reproduced below that lists clinical features that involve six areas of psychosocial functioning and are organized by "overt" and "covert" manifestations.

"Overt" and "covert" are intended to denote seemingly contradictory aspects that may both simultaneously be present in an individual.[240] These designations do not necessarily imply their conscious or unconscious existence. The covert characteristics are by definition difficult to discern and not immediately apparent. Additionally, the lack of data on the frequency of many of the features makes their relative diagnostic weight difficult to distinguish at this time. However, Akhtar states that his profile has several advantages over the DSM in terms of maintaining historical continuity of the use of the word schizoid, valuing depth and complexity over descriptive oversimplification and helping provide a more meaningful differential diagnosis of SzPD from other personality disorders.[240]

Clinical features of schizoid personality disorder[241]
Area Overt characteristics Covert characteristics
Self-concept
Interpersonal relations
  • withdrawn
  • aloof
  • have few close friends
  • impervious to others' emotions
  • afraid of intimacy
  • exquisitely sensitive
  • deeply curious about others
  • hungry for love
  • envious of others' spontaneity
  • intensely needy of involvement with others
  • capable of excitement with carefully selected intimates
Social adaptation
  • lack clarity of goals
  • weak ethnic affiliation
  • usually capable of steady work
  • quite creative and may make unique and original contributions
  • capable of passionate endurance in certain spheres of interest
Love and sexuality
Ethics, standards, and ideals
  • moral unevenness
  • occasionally strikingly amoral and vulnerable to odd crimes, at other times altruistically self-sacrificing
Cognitive style
  • autistic thinking
  • fluctuations between sharp contact with external reality and hyperreflectiveness about the self
  • autocentric use of language

Differential Diagnosis

Psychological condition Features
Other mental disorders with psychotic symptoms Symptoms of Schizoid Personality Disorder can appear during the course of disorder with psychotic features such as delusional disorder. However, SzPD does not require the presence of any psychotic symptoms such as hallucinations or delusions.[242]
Depression People who have SzPD may also have clinical depression. However, this is not always the case. Unlike people with depression, persons with SzPD generally do not consider themselves inferior to others. They may recognize instead that they are "different".
Autism Spectrum Disorder There may be substantial difficulty in distinguishing Asperger syndrome (AS), sometimes called "schizoid disorder of childhood", from SzPD. But while AS is an autism spectrum disorder, SzPD is classified as a "schizophrenia-like" personality disorder. There is some overlap, as some people with autism also qualify for a diagnosis of schizotypal or schizoid PD. However, one of the distinguishing features of schizoid PD is a restricted affect and an impaired capacity for emotional experience and expression. Persons with AS are "hypo-mentalizers", i.e., they fail to recognize social cues such as verbal hints, body language and gesticulation, but those with schizophrenia-like personality disorders tend to be "hyper-mentalizers", overinterpreting such cues in a generally suspicious way.[243][244][245] Although they may have been socially isolated from childhood onward, most people with SzPD displayed well-adapted social behavior as children, along with apparently normal emotional function. SzPD also does not require impairments in nonverbal communication such as a lack of eye contact, unusual prosody or a pattern of restricted interests or repetitive behaviors.[246]
Personality change due to another medical condition Traits of Schizoid Personality Disorder can appear due to damage to the central nervous system.[247]
Substance use Disorders Traits of Schizoid Personality Disorder can appear due to substance abuse.[248]
Other personality disorders and personality traits Schizoid and narcissistic personality disorders can seem similar in some respects (e.g. both show identity confusion, may lack warmth and spontaneity, avoid deep relationships with intimacy). Another commonality observed by Akhtar is preferring ideas over people and displaying "intellectual hypertrophy", with a corresponding lack of rootedness in bodily existence. There are, nonetheless, important differences. The schizoid hides his need for dependency and is rather fatalistic, passive, cynical, overtly bland or vaguely mysterious. The narcissist is, in contrast, ambitious and competitive and exploits others for his dependency needs.[249] There are also parallels between SzPD and obsessive-compulsive personality disorder (OCPD), such as detachment, restricted emotional expression and rigidity. However, in OCPD the capacity to develop intimate relationships is usually intact, but deep contacts may be avoided because of an unease with emotions and a devotion to work.[250][251] While people affected with APD avoid social interactions due to anxiety or feelings of incompetence, those with SzPD do so because they are genuinely indifferent to social relationships. A 1989 study,[252] however, found that "schizoid and avoidant personalities were found to display equivalent levels of anxiety, depression, and psychotic tendencies as compared to psychiatric control patients." There also seems to be some shared genetic risk between SzPD and AvPD (see schizoid-avoidant behavior). Several sources have confirmed the synonymy of SzPD and avoidant attachment style.[253] However, the distinction should be made that individuals with SzPD characteristically do not seek social interactions merely due to lack of interest, while those with avoidant attachment style can in fact be interested in interacting with others but without establishing connections of much depth or length due to having little tolerance for any kind of intimacy.

See also

References

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