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Psychosis
Psychosis
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Psychosis is a generic psychiatric term for a mental state in which thought and perception are severely impaired. Persons experiencing a psychotic episode may experience hallucinations, hold delusional beliefs (e.g., grandiose or paranoid delusions), demonstrate personality changes and exhibit disorganized thinking (see thought disorder). This is often accompanied by lack of insight into the unusual or bizarre nature of such behavior, difficulties with social interaction and impairments in carrying out the activities of daily living. A psychotic episode is often described as involving a "loss of contact with reality".

Etymology

The word psychosis was first used by Ernst von Feuchtersleben in 1845 ^[1] as an alternative to insanity and mania and stems from the Greek psyche (mind) and -osis (diseased or abnormal condition).^[2] The word was used to distinguish disorders which were thought to be disorders of the mind, as opposed to neurosis, which was thought to stem from a disorder of the nervous system.

Overview

Psychosis is considered by mainstream psychiatry to be a symptom of severe mental illness, but is not a diagnosis in itself. Although it is not exclusively linked to any particular psychological or physical state, it is particularly associated with schizophrenia, bipolar disorder (manic depression) and severe clinical depression. There are also detectable physical pathologies that can induce a psychotic state, including brain injury or other neurological disorder, drug intoxication and withdrawal (especially alcohol, barbiturates, and sometimes benzodiazepines), lupus, electrolyte disorder in the elderly (such as urinary tract infections) and pain syndromes.

The term psychosis should be distinguished from the concept of insanity, which is a legal term denoting that a person should not be criminally responsible for his actions. Similarly, it should be distinguished from psychopathy, a personality disorder often associated with violence, lack of empathy and socially manipulative behavior. Despite the fact that both are colloquially abbreviated to "psycho", psychosis bears little similarity to psychopathy's core features, particularly with regard to violence, which rarely occurs in psychosis, and the distortion of perceived reality, which rarely occurs in psychopathy.

Psychosis should also be distinguished from the state of delirium, in that a psychotic individual may be able to perform actions that require a high level of intellectual effort in clear consciousness. Finally, it should be distinguished from mental illness in general. Psychosis may be regarded as a symptom of other mental illnesses, but as a descriptive concept it is not considered an illness in its own right. For example, persons with schizophrenia can have long periods without psychosis, and persons with bipolar disorder and depression can have mood symptoms without psychosis. Conversely, psychosis can occur in persons without chronic mental illness, as a result of an adverse drug reaction or extreme stress.

Psychotic states occurring after drug use may be particularly linked to drug overdose, chronic use and drug withdrawal. Certain compounds may be more likely to induce psychosis and some individuals may show greater sensitivity than others. Certain "street" drugs, such as cocaine, amphetamines, PCP^[3] and hallucinogens are particularly linked to the development of psychosis. Anticholinergic drugs (atropine, scopolamine, Jimson weed), and many antihistamines can also induce psychosis at high enough dosages.^[4]^[5]^[6]^[7]

Intoxication with drugs that have general depressant effects on the central nervous system (especially alcohol and barbiturates) tend not to cause psychosis during use, and can actually decrease or lessen the impact of symptoms in some people. Withdrawal from barbiturates and alcohol can be particularly dangerous, however, leading to psychosis or delirium and other, potentially lethal, withdrawal effects.

Psychological stress is also known to contribute to and trigger psychotic states. Both a history of traumatic incidents experienced throughout the life-span, and the recent experience of a stressful event, is thought to contribute to the development of psychosis. Short-lived psychosis triggered by stress is known as brief reactive psychosis.

Sleep deprivation has been linked to psychosis,^[8]^[9]^[10] although there is little evidence to suggest that it is a major risk factor in the majority of people. Some people experience hypnagogic or hypnopompic hallucinations, where unusual sensory experiences or thoughts appear during waking or drifting off to sleep. These are normal sleep phenomena, however, and are not considered signs of psychosis.

During the 1960s and 1970s, psychosis was of particular interest to counterculture critics of mainstream psychiatric practice, who argued that it may simply be another way of constructing reality and is not necessarily a sign of illness. For example, R. D. Laing argued that psychosis is a symbolic way of expressing concerns in situations where such views may be unwelcome or uncomfortable to the recipients. He went on to say that psychosis could be also seen as a transcendental experience with healing and spiritual aspects. Thomas Szasz focused on the social implications of labelling people as psychotic; a label he argues unjustly medicalises different views of reality so such unorthodox people can be controlled by society.

Generally, however, advances in both diagnosis and the scientific study of psychosis have led to theories drawing on biology, cognitive psychology and neuropsychology being accepted as mainstream explanations. In the United States and Europe, few reputable practitioners since the 1990s have approached psychosis outside this scientific frame of reference.

Antipsychotic medication is usually the first line treatment for psychosis and can potentially minimize or eliminate the symptoms within a relatively rapid amount of time. Cognitive behavioral therapy is now recommended by many clinical standards organizations as an effective psychological treatment for psychosis.

Psychotic experience

A psychotic episode can be significantly affected by mood. For example, people experiencing a psychotic episode in the context of depression may experience persecutory or self-blaming delusions or hallucinations, while people experiencing a psychotic episode in the context of mania may form grandiose delusions or have an experience of deep religious significance.

Although usually distressing and regarded as an illness process, some people who experience psychosis find beneficial aspects and value the experience or revelations that stem from it.

Hallucinations

Hallucinations are defined as sensory perception in the absence of external stimuli. They are different from illusions, which are the misperception of external stimuli. Hallucinations may occur in any of the five senses and take on almost any form, which may include simple sensations (such as lights, colors, tastes, smells) to more meaningful experiences such as seeing and interacting with fully formed animals and people, hearing voices and complex tactile sensations.

Auditory hallucinations, particularly the experience of hearing voices, are a common and often prominent feature of psychosis. Hallucinated voices may talk about, or to the person, and may involve several speakers with distinct personas. Auditory hallucinations tend to be particularly distressing when they are derogatory, commanding or preoccupying. However, the experience of hearing voices need not always be a negative one. Research has shown that the majority of people who hear voices are not in need of psychiatric help.^[11] The Hearing Voices Movement has subsequently been created to support voice hearers, regardless of whether they are considered to have a mental illness or not.

Delusions and paranoia

Psychosis may involve delusional or paranoid beliefs. Karl Jaspers classified psychotic delusions into primary and secondary types. Primary delusions are defined as arising out-of-the-blue and not being comprehensible in terms of normal mental processes, whereas secondary delusions may be understood as being influenced by the person's background or current situation (i.e. ethnic or sexual descrimination, religious, superstitious belief).^[12]

Thought disorder

Formal thought disorder describes an underlying disturbance to conscious thought and is classified largely by its effects on speech and writing. Affected persons may show pressure of speech (speaking incessantly and quickly), derailment or flight of ideas (switching topic mid-sentence or inappropriately), thought blocking, and rhyming or punning.

Lack of insight

One important and puzzling feature of psychosis is usually an accompanying lack of insight into the unusual, strange, or bizarre nature of the person's experience or behaviour. Even in the case of an acute psychosis, sufferers may seem completely unaware that their vivid hallucinations and impossible delusions are in any way unrealistic. This is not an absolute, however; insight can vary between individuals and throughout the duration of the psychotic episode.

In some cases, particularly with auditory and visual hallucinations, the patient has good insight, which makes the psychotic experience even more terrifying because the patient realizes that he or she should not be hearing voices, but is.

Medical understanding

There are a number of possible causes for psychosis. Psychosis may be the result of an underlying mental illness such as bipolar disorder (also known as manic depression) or schizophrenia. Psychosis may also be triggered or exacerbated by severe mental stress and high doses or chronic use of drugs such as amphetamines, LSD, PCP, cocaine or scopolamine. However, incidence of psychosis resulting from a single administration of any drug is rare, although cases have been reported in the medical literature suggesting a person's sensitivities to new compounds can be unpredictable. Sudden withdrawal from CNS depressant drugs, such as alcohol and benzodiazepines, may also trigger psychotic episodes. As can be seen from the wide variety of illnesses and conditions in which psychosis has been reported to arise (including, for example, AIDS, leprosy, malaria and even mumps) there is no singular cause of a psychotic episode.

The division of the major psychoses into manic depressive insanity (now called bipolar disorder) and dementia praecox (now called schizophrenia) was made by Emil Kraepelin, who attempted to create a synthesis of the various mental disorders identified by 19th century psychiatrists, by grouping diseases together based on classification of common symptoms. Kraepelin used the term 'manic depressive insanity' to describe the whole spectrum of mood disorders, in a far wider sense than it is usually used today. In Kraepelin's classification this would include 'unipolar' clinical depression, as well as bipolar disorder and other mood disorders such as cyclothymia. These are characterised by problems with mood control and the psychotic episodes appear associated with disturbances in mood, and patients will often have periods of normal functioning between psychotic episodes even without medication. Schizophrenia is characterized by psychotic episodes which appear to be unrelated to disturbances in mood, and most non-medicated patients will show signs of disturbance between psychotic episodes.

Psychotic episodes may vary in duration between individuals. In brief reactive psychosis, the psychotic episode is related directly to a specific stressful life event, so patients may spontaneously recover normal functioning within two weeks.^[13] In some rare cases, individuals may remain in a state of full-blown psychosis for many years, or perhaps have attenuated psychotic symptoms (such as low intensity hallucinations) present at most times.

Patients who are undergoing a brief psychotic episode may have many of the same symptoms as a person who is psychotic as a result of (for example) schizophrenia, and this fact has been used to support the notion that psychosis is primarily a breakdown in some specific biological system in the brain. The dopamine hypothesis of psychosis was an early, and still popular, example of a theory based on this assumption. However, it is controversial how much weight should be given to such exclusively biological theories as it has become clearer that a wide range of influences (including environmental, social and childhood development factors) may contribute to the final experience of psychosis.

It has also been argued that psychosis exists on a continuum as everybody may have some unusual and potentially reality-distorting experiences in their life. This has been backed up by research showing that experiences such as hallucinations have been experienced by large numbers of the population who may never be impaired or even distressed by their experiences.^[14] In this view, people who are diagnosed with a psychotic illness may simply be one end of a spectrum where the experiences become particularly intense or distressing (see schizotypy).

Brain function

The first brain image of a person with psychosis was completed as far back as 1935 using a technique called pneumoencephalography^[15] (a painful and now obsolete procedure where cerebrospinal fluid is drained from around the brain and replaced with air to allow the structure of the brain to show up more clearly on an X-ray picture).

Modern brain imaging studies, investigating both changes in brain structure and changes in brain function of people undergoing psychotic episodes, have shown mixed results.

A 2003 study investigating structural changes in the brains of people with psychosis showed there was significant grey matter reduction in the cortex of people before and after they became psychotic.^[16] Findings such as these have led to debate about whether psychosis is itself neurotoxic and whether potentially damaging changes to the brain are related to the length of psychotic episode. Recent research has suggested that this is not the case^[17] although further investigation is still ongoing.

Functional brain scans have revealed that the areas of the brain that react to sensory perceptions are active during psychosis. For example, a PET or fMRI scan of a person who claims to be hearing voices may show activation in the auditory cortex, or parts of the brain involved in the perception and understanding of speech.^[18]

On the other hand, there is not a clear enough psychological definition of belief to make a comparison between different people particularly valid. Brain imaging studies on delusions have typically relied on correlations of brain activation patterns with the presence of delusional beliefs.^[19]

One clear finding is that persons with a tendency to have psychotic experiences seem to show increased activation in the right hemisphere of the brain.^[20] This increased level of right hemisphere activation has also been found in healthy people who have high levels of paranormal beliefs^[21] and in people who report mystical experiences.^[22] It also seems to be the case that people who are more creative are also more likely to show a similar pattern of brain activation.^[23] Some researchers have been quick to point out that this in no way suggests that paranormal, mystical or creative experiences are in any way by themselves a symptom of mental illness, as it is still not clear what makes some such experiences beneficial whilst others lead to the impairment or distress of diagnosable mental pathology. However, people who have profoundly different experiences of reality or hold unusual views or opinions have traditionally held a complex role in society, with some being viewed as kooks, whilst others are lauded as prophets or visionaries.

Psychosis has been traditionally linked to the neurotransmitter dopamine. In particular, the dopamine hypothesis of psychosis has been influential and states that psychosis results from an overactivity of dopamine function in the brain, particularly in the mesolimbic pathway. The two major sources of evidence given to support this theory are that dopamine-blocking drugs (i.e. antipsychotics) tend to reduce the intensity of psychotic symptoms, and that drugs which boost dopamine activity (such as amphetamine and cocaine) can trigger psychosis in some people (see amphetamine psychosis).^[24]

The connection between dopamine and psychosis is generally believed to be complex. First of all, while antipsychotic drugs immediately block dopamine receptors, they usually take a week or two to reduce the symptoms of psychosis. Moreover, newer and equally effective antipsychotic drugs actually block slightly less dopamine in the brain than older drugs whilst also affecting serotonin function, suggesting the 'dopamine hypothesis' is vastly oversimplified.^[25]

Psychiatrist David Healy has criticised pharmaceutical companies for promoting simplified biological theories of mental illness that seem to imply the primacy of pharmaceutical treatments while ignoring social and developmental factors which are known to be important influences in the aetiology of psychosis.^[26]

Some theories regard many psychotic symptoms to be a problem with the perception of ownership of internally generated thoughts and experiences.^[27] For example, the experience of hearing voices may arise from internally generated speech that is mislabeled by the psychotic person as coming from an external source.

Cannabis

There is growing evidence for a small but significant link between cannabis use and vulnerability to psychosis.^[28] Some studies indicate that cannabis use correlates with a slight increase in psychotic experience, which may help trigger full-blown psychosis in some people.^[28] Early studies have been criticized for failing to consider other drugs (such as LSD) that the participants may also have used before or during the study, as well as other factors such as possible pre-existing mental health issues. However, more recent studies with better controls have still found a small increase in risk for psychosis in cannabis users. It is not clear whether this is a causal link, and it may be that cannabis use only increases the chance of psychosis in people already predisposed to it. Additionally, people with developing psychosis possibly make greater use of the drug to provide temporary relief to their mental discomfort. The fact that cannabis use has increased over the past few decades, whereas the rate of psychosis has not,^[29] suggests that a direct causal link is unlikely for all users.

Non-psychiatric conditions

Psychosis can be a feature of several diseases, often when the brain or nervous system is directly affected. However, the fact that psychosis can occasionally arise in parallel with a number of ailments (including diseases such as flu or mumps for example) suggests that a variety of nervous system stressors can lead to a psychotic reaction. Psychosis arising from non-psychiatric conditions is sometimes known as 'secondary psychosis'. The mechanisms by which this happens are still not clear, but the non-specificity of psychosis has led Tsuang and colleagues to argue that "psychosis is the 'fever' of mental illness—a serious but nonspecific indicator".^[30]

Non-psychiatric conditions which are particularly linked to psychosis include brain tumour,^[31] dementia with Lewy bodies,^[32] hypoglycemia,^[33] intoxication,^[34] multiple sclerosis,^[35] Systemic Lupus Erythematosus,^[36] and sarcoidosis.^[37]

Treatment

The treatment of psychosis often depends on what associated diagnosis (such as schizophrenia or bipolar disorder) is thought to be present. However, the first line treatment for psychotic symptoms is usually antipsychotic medication, and in some cases hospitalisation. There is growing evidence that cognitive behavior therapy^[38] and family therapy^[39] can be effective in managing psychotic symptoms. When other treatments for psychosis are ineffective, electroconvulsive therapy (ECT) (aka shock treatment) is sometimes utilized to relieve the underlying symptoms of psychosis, such as depression or schizophrenia.

References

^ Beer, M D (1995). "Psychosis: from mental disorder to disease concept". Hist Psychiatry. 6 (22(II)). PubMed: 177–200. PMID 11639691. Retrieved 2006-08-19. {{cite journal}}: Cite has empty unknown parameter: |coauthors= (help)
^ "Online Etymology Dictionary". Douglas Harper. 2001. Retrieved 2006-08-19. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
^ Reynolds, Lindsay M. (March 1, 2005). "Chronic phencyclidine administration induces schizophrenia-like changes in N-acetylaspartate and N-acetylaspartylglutamate in rat brain". Schizophrenia Research. 73 (2–3): 147–152. doi:10.1016/j.schres.2004.02.003. PMID 15653257. Retrieved 2006-09-29. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Sexton, J. D. (1997). "Diphenhydramine-induced psychosis with therapeutic doses". American Journal of Emergency Medicine. 15 (5): 548–549. PMID 9270406. Retrieved 2006-09-29. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ Lang, K. (December 8, 1995). "[An anticholinergic syndrome with hallucinatory psychosis after diphenhydramine poisoning]". Deutsche medizinische Wochenschrift. 120 (49): 1695–1698. PMID 7497894. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Schreiber, W. (February 5, 1988). "[Toxic psychosis as an acute manifestation of diphenhydramine poisoning]". Deutsche medizinische Wochenschrift. 113 (5): 180–183. PMID 3338401. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Timnak, Charles (2004). "Promethazine-Induced Psychosis in a 16-Year-Old Girl". Psychosomatics. 45 (1): 89–90. PMID 14709767. Retrieved 2006-09-29. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ Sharma, Verinder (2003). "Sleep loss and postpartum psychosis". Bipolar Disorders. 5 (2): 98–105. doi:10.1034/j.1399-5618.2003.00015.x. PMID 12680898. Retrieved 2006-09-27. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ Chan-Ob, T. (1999). "Meditation in association with psychosis". Journal of the Medical Association of Thailand. 82 (9): 925–930. PMID 10561951. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ Devillieres, P. (1996). "[Delusion and sleep deprivation]". L'Encéphale. 22 (3): 229–231. Parameter error in {{PMID}}: Missing PMID.. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ Honig, A (1998). "Auditory hallucinations: a comparison between patients and nonpatients". Journal of Nervous and Mental Disease. Retrieved 2006-08-19. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Jaspers, Karl (1997-11-27) [1963]. Allgemeine Psychopathologie (General Psychopathology). Translated by J. Hoenig & M.W. Hamilton from German (Reprint edtion ed.). Baltimore, Maryland: Johns Hopkins University Press. ISBN 0801857759.
^ Jauch, DA (1988). "Reactive psychosis. I. Does the pre-DSM-III concept define a third psychosis?". Journal of Nervous and Mental Disease. Retrieved 2006-08-19. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Johns, LC (2001). "The continuity of psychotic experiences in the general population". Clinical Psychology Review. 21 (8). PubMed: 1125–41. PMID 11702510. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Moore, M T (1935). "Encephalographic studies in mental disease". American Journal of Psychiatry. 92 (1): 43–67. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Pantelis, C (2003). "Neuroanatomical abnormalities before and after onset of psychosis: a cross-sectional and longitudinal MRI comparison". Lancet. 25 (361 (9354)). PubMed: 281–8. PMID 12559861. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Ho, BC (2003). "Untreated initial psychosis: relation to cognitive deficits and brain morphology in first-episode schizophrenia". American Journal of Psychiatry. 160 (1). PubMed: 142–148. PMID 12505813. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Copolov DL, Seal ML, Maruff P, Ulusoy R, Wong MT, Tochon-Danguy HJ, Egan GF. (2003) Cortical activation associated with the experience of auditory hallucinations and perception of human speech in schizophrenia: a PET correlation study. Psychiatry Res, 122 (3), 139-52. PMID 12694889.
^ Bell, V., Halligan, P.W. & Ellis, H.D. (2006) A Cognitive Neuroscience of Belief. In P.W. Halligan & M. Aylward (eds) The Power of Belief. Oxford: Oxford University Press.
^ Lohr, JB (1997). "Lateralized hemispheric dysfunction in the major psychotic disorders: historical perspectives and findings from a study of motor asymmetry in older patients". Schizophrophrenia Research. 30 (27 (2-3)). PubMed: 191–8. PMID 9416648. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Pizaagalli, D (2000). "Brain electric correlates of strong belief in paranormal phenomena: intracerebral EEG source and regional Omega complexity analyses". Psychiatry Research. 100 (3). PubMed: 139–154. PMID 11120441. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Makarec, K (1985). "Temporal lobe signs: electroencephalographic validity and enhanced scores in special populations". Perceptual and Motor Skills. 60 (3). PubMed: 831–842. PMID 3927256. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Weinstein, S (2002). "Are creativity and schizotypy products of a right hemisphere bias?". Brain and Cognition. 49 (1). PubMed: 138–151. PMID 12027399. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Kapur S, Mizrahi R, Li M. (2005) From dopamine to salience to psychosis - linking biology, pharmacology and phenomenology of psychosis. Schizophr Res, 79 (1), 59-68. PMID 16005191
^ Jones, H. M., & Pilowsky, L. S. (2002) Dopamine and antipsychotic drug action revisited. British Journal of Psychiatry, 181, 271-275. PMID 12356650
^ Healy, David (2002). The Creation of Psychopharmacology. Cambridge: Harvard University Press. ISBN 0-674-00619-4. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
^ Blakemore, SJ (2000). "The perception of self-produced sensory stimuli in patients with auditory hallucinations and passivity experiences: evidence for a breakdown in self-monitoring". Psychological Medicine. 30 (5). PubMed: 1131–9. PMID 12027049. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ ^a ^b Degenhardt, L (2003). "Editorial: The link between cannabis use and psychosis: furthering the debate". Psychological Medicine. 33. PubMed: 3–6. PMID 12537030. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) Cite error: The named reference "Deg" was defined multiple times with different content (see the help page).
^ Degenhardt L, Hall W, Lynskey M (2001). "Comorbidity between cannabis use and psychosis: Modelling some possible relationships" (PDF). Technical Report No. 121. Sydney: National Drug and Alcohol Research Centre. Retrieved 2006-08-19. {{cite journal}}: Cite journal requires |journal= (help)CS1 maint: multiple names: authors list (link)
^ Tsuang, MT (2000). "Toward reformulating the diagnosis of schizophrenia". American Journal of Psychiatry. 157 (7). PubMed: 1041–1050. PMID 10873908. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Lisanby, S. H. (1998). "Psychosis Secondary to Brain Tumor". Seminars in clinical neuropsychiatry. 3 (1): 12–22. PMID 10085187. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ McKeith, Ian G. (2002). "Dementia with Lewy bodies". British Journal of Psychiatry. 180: 144–147. PMID 11823325. Retrieved 2006-09-27. {{cite journal}}: Unknown parameter |month= ignored (help)
^ Template:Cite online journal
^ Larson, Michael (2006-03-30). "Alcohol-Related Psychosis". eMedicine. WebMD. {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
^ Template:Es icon Rodriguez Gomez, Diego (August 16-31, 2005). "Psicosis aguda como inicio de esclerosis multiple / Acute psychosis as the presenting symptom of multiple sclerosis / Psicose aguda como inicio de esclerose multipla". Revista de Neurología. 41 (4): 255–256. PMID 16075405. Retrieved 2006-09-27. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Robert, M. (2006). "Neuropsychiatric manifestations systemic lupus erythematosus: A study from South India". Neurology India. 54 (1): 75–77. PMID 16679649. Retrieved 2006-09-29. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ Bona, Joseph R. (1998). "Neurosarcoidosis as a Cause of Refractory Psychosis: A Complicated Case Report". American Journal of Psychiatry. 155 (8): 1106–1108. PMID 9699702. Retrieved 2006-09-29. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
^ Birchwood, M (2006). "The future of cognitive-behavioural therapy for psychosis: not a quasi-neuroleptic". British Journal of Psychiatry. 188: 108–108. PMID 16449695. {{cite journal}}: |access-date= requires |url= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
^ Haddock, G (2005). "Psychological interventions in early psychosis". Schizophrenia Bulletin. 31 (3): 697–704. PMID 16006594. {{cite journal}}: |access-date= requires |url= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)

External links

Understanding psychotic experiences from mental health charity Mind

[1] Beer, M D (1995). "Psychosis: from mental disorder to disease concept". Hist Psychiatry. 6 (22(II)). PubMed: 177–200. PMID 11639691. Retrieved 2006-08-19. {{cite journal}}: Cite has empty unknown parameter: |coauthors= (help)

[2] "Online Etymology Dictionary". Douglas Harper. 2001. Retrieved 2006-08-19. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)

[psychotic_PCP_rats-3] Reynolds, Lindsay M. (March 1, 2005). "Chronic phencyclidine administration induces schizophrenia-like changes in N-acetylaspartate and N-acetylaspartylglutamate in rat brain". Schizophrenia Research. 73 (2–3): 147–152. doi:10.1016/j.schres.2004.02.003. PMID 15653257. Retrieved 2006-09-29. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)

[diphenhydramine_trip_therapeutic-4] Sexton, J. D. (1997). "Diphenhydramine-induced psychosis with therapeutic doses". American Journal of Emergency Medicine. 15 (5): 548–549. PMID 9270406. Retrieved 2006-09-29. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

[diphenhydramine_trip_supratherapeutic-5] Lang, K. (December 8, 1995). "[An anticholinergic syndrome with hallucinatory psychosis after diphenhydramine poisoning]". Deutsche medizinische Wochenschrift. 120 (49): 1695–1698. PMID 7497894. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)

[diphenhydramine_poisoning_psychosis-6] Schreiber, W. (February 5, 1988). "[Toxic psychosis as an acute manifestation of diphenhydramine poisoning]". Deutsche medizinische Wochenschrift. 113 (5): 180–183. PMID 3338401. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)

[Promethazine-7] Timnak, Charles (2004). "Promethazine-Induced Psychosis in a 16-Year-Old Girl". Psychosomatics. 45 (1): 89–90. PMID 14709767. Retrieved 2006-09-29. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

[sleep_dep1-8] Sharma, Verinder (2003). "Sleep loss and postpartum psychosis". Bipolar Disorders. 5 (2): 98–105. doi:10.1034/j.1399-5618.2003.00015.x. PMID 12680898. Retrieved 2006-09-27. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

[sleep_dep2-9] Chan-Ob, T. (1999). "Meditation in association with psychosis". Journal of the Medical Association of Thailand. 82 (9): 925–930. PMID 10561951. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

[sleep_dep3-10] Devillieres, P. (1996). "[Delusion and sleep deprivation]". L'Encéphale. 22 (3): 229–231. Parameter error in {{PMID}}: Missing PMID.. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

[11] Honig, A (1998). "Auditory hallucinations: a comparison between patients and nonpatients". Journal of Nervous and Mental Disease. Retrieved 2006-08-19. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)

[Jaspers-12] Jaspers, Karl (1997-11-27) [1963]. Allgemeine Psychopathologie (General Psychopathology). Translated by J. Hoenig & M.W. Hamilton from German (Reprint edtion ed.). Baltimore, Maryland: Johns Hopkins University Press. ISBN 0801857759.

[13] Jauch, DA (1988). "Reactive psychosis. I. Does the pre-DSM-III concept define a third psychosis?". Journal of Nervous and Mental Disease. Retrieved 2006-08-19. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)

[14] Johns, LC (2001). "The continuity of psychotic experiences in the general population". Clinical Psychology Review. 21 (8). PubMed: 1125–41. PMID 11702510. Retrieved 2006-08-19. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)

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[multiple_sclerosis-35] Template:Es icon Rodriguez Gomez, Diego (August 16-31, 2005). "Psicosis aguda como inicio de esclerosis multiple / Acute psychosis as the presenting symptom of multiple sclerosis / Psicose aguda como inicio de esclerose multipla". Revista de Neurología. 41 (4): 255–256. PMID 16075405. Retrieved 2006-09-27. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)

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-{{DiseaseDisorder infobox |
-  Name        = Psychosis |
-  ICD10       = |
-  ICD9        = {{ICD9|290}}-{{ICD9|299}} |
-}}
 {{For|the professional wrestler known as Psychosis|Dionicio Castellanos}}
+{{Infobox_Disease |
-'''Psychosis''' is a generic [[psychiatry|psychiatric]] term for a [[Mental status examination|mental state]] in which thought and perception are severely impaired. Persons experiencing a psychotic episode may experience [[hallucination]]s, hold [[delusion|delusional]] beliefs (e.g., grandiose or [[paranoia|paranoid]] delusions), demonstrate [[personality]] changes and exhibit disorganized thinking (see [[thought disorder]]). This is often accompanied by [[anosognosia|lack of insight]] into the unusual or bizarre nature of such behavior, difficulties with social interaction and impairments in carrying out the activities of daily living. A psychotic episode is often described as involving a "loss of contact with reality."
+  Name           = {{PAGENAME}} |
+  Image          = |
+  Caption        = |
+  DiseasesDB     = |
+  ICD10          = |
+  ICD9           = {{ICD9|290}}-{{ICD9|299}} |
+  ICDO           = |
+  OMIM           = 603342 |
+  OMIM_mult      = {{OMIM2|608923}} {{OMIM2|603175}} {{OMIM2|192430}}|
+  MedlinePlus    = 001553 |
+  eMedicineSubj  = |
+  eMedicineTopic = |
+  MeshID         = 68011618 |
+}}
+'''Psychosis''' is a generic [[psychiatry|psychiatric]] term for a [[Mental status examination|mental state]] in which thought and perception are severely impaired. Persons experiencing a psychotic episode may experience [[hallucination]]s, hold [[delusion|delusional]] beliefs (e.g., grandiose or [[paranoia|paranoid]] delusions), demonstrate [[personality]] changes and exhibit disorganized thinking (see [[thought disorder]]). This is often accompanied by [[anosognosia|lack of insight]] into the unusual or bizarre nature of such behavior, difficulties with social interaction and impairments in carrying out the activities of daily living. A psychotic episode is often described as involving a "loss of contact with reality".
 ==Etymology==
-The word ''psychosis'' was first used by [[Baron Ernst Von Feuchtersleben|Ernst von Feuchtersleben]] in 1845<ref> {{cite journal| last = Beer| first = M D | authorlink = | coauthors = | title = Psychosis: from mental disorder to disease concept. | journal = Hist Psychiatry| volume = 6| issue = 22(II)| pages = 177-200| publisher = PubMed| date = 1995| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=Display&DB=pubmed| doi = | id = PMID 11639691| accessdate = 2006-08-19 }}</ref> as an alternative to [[insanity]] and [[mania]] and stems from the Greek ''psyche'' (mind) and ''-osis'' (diseased or abnormal condition).<ref>{{cite web| last = | first = | authorlink = | coauthors = | title = Online Etymology Dictionary| work = | publisher = Douglas Harper| date = 2001| url = http://www.etymonline.com/index.php?search=psychosis&searchmode=none| format = | doi = | accessdate = 2006-08-19 }}</ref> The word was used to distinguish disorders which were thought to be disorders of the mind, as opposed to [[neurosis]], which was thought to stem from a disorder of the nervous system.
+The word ''psychosis'' was first used by [[Baron Ernst Von Feuchtersleben|Ernst von Feuchtersleben]] in 1845 <ref> {{cite journal| last = Beer| first = M D | authorlink = | coauthors = | title = Psychosis: from mental disorder to disease concept. | journal = Hist Psychiatry| volume = 6| issue = 22(II)| pages = 177-200| publisher = PubMed| date = 1995| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=Display&DB=pubmed| doi = | id = PMID 11639691| accessdate = 2006-08-19 }}</ref> as an alternative to [[insanity]] and [[mania]] and stems from the Greek ''psyche'' (mind) and ''-osis'' (diseased or abnormal condition).<ref>{{cite web| last = | first = | authorlink = | coauthors = | title = Online Etymology Dictionary| work = | publisher = Douglas Harper| date = 2001| url = http://www.etymonline.com/index.php?search=psychosis&searchmode=none| format = | doi = | accessdate = 2006-08-19 }}</ref> The word was used to distinguish disorders which were thought to be disorders of the mind, as opposed to [[neurosis]], which was thought to stem from a disorder of the nervous system.
 ==Overview==
+{{unreferencedsect}}
 Psychosis is considered by mainstream [[psychiatry]] to be a symptom of severe mental illness, but is not a [[diagnosis]] in itself. Although it is not exclusively linked to any particular psychological or physical state, it is particularly associated with [[schizophrenia]], [[bipolar disorder]] (manic depression) and severe [[clinical depression]]. There are also detectable physical [[pathology|pathologies]] that can induce a psychotic state, including [[brain injury]] or other [[Neurology|neurological disorder]], drug intoxication and [[withdrawal]] (especially [[ethanol|alcohol]], [[barbiturate]]s, and sometimes [[benzodiazepine]]s), [[Systemic Lupus Erythematosus|lupus]], electrolyte disorder in the elderly (such as [[urinary tract infections]]) and pain syndromes.
-The term ''psychosis'' should be distinguished from the concept of [[insanity]], which is a legal term denoting that a person should not be criminally responsible for his actions. Similarly, it should be distinguished from [[psychopathy]], a [[personality disorder]] often associated with violence, lack of [[empathy]] and socially manipulative behavior. Despite the fact that both are colloquially abbreviated to "psycho", psychosis bears little similarity to psychopathy's core features, particularly with regard to violence, which rarely occurs in psychosis, and the distortion of perceived reality, which rarely occurs in psychopathy.
+The term ''psychosis'' should be distinguished from the concept of insanity, which is a legal term denoting that a person should not be criminally responsible for his actions. Similarly, it should be distinguished from [[psychopathy]], a [[personality disorder]] often associated with violence, lack of [[empathy]] and socially manipulative behavior. Despite the fact that both are colloquially abbreviated to "psycho", psychosis bears little similarity to psychopathy's core features, particularly with regard to violence, which rarely occurs in psychosis, and the distortion of perceived reality, which rarely occurs in psychopathy.
-Psychosis should also be distinguished from the state of [[delirium]], in that a psychotic individual may be able to perform actions that require a high level of intellectual effort in clear consciousness. Finally, it should be distinguished from mental illness. Psychosis may be regarded as a symptom of other mental illnesses, but as a descriptive concept it is not considered an illness in its own right. For example, persons with [[schizophrenia]] can have long periods without psychosis, and persons with [[bipolar disorder]] and depression can have mood symptoms without psychosis. Conversely, psychosis can occur in persons without chronic mental illness, as a result of an adverse drug reaction or extreme stress.
+Psychosis should also be distinguished from the state of [[delirium]], in that a psychotic individual may be able to perform actions that require a high level of intellectual effort in clear consciousness. Finally, it should be distinguished from mental illness in general. Psychosis may be regarded as a symptom of other mental illnesses, but as a descriptive concept it is not considered an illness in its own right. For example, persons with schizophrenia can have long periods without psychosis, and persons with bipolar disorder and depression can have mood symptoms without psychosis. Conversely, psychosis can occur in persons without chronic mental illness, as a result of an adverse drug reaction or extreme stress.
+Psychotic states occurring after [[Psychoactive drug|drug]] use may be particularly linked to [[drug overdose]], chronic use and drug withdrawal. Certain compounds may be more likely to induce psychosis and some individuals may show greater sensitivity than others. Certain "street" drugs, such as [[cocaine]], [[amphetamine]]s, [[Phencyclidine|PCP]]<ref name=psychotic_PCP_rats>{{cite journal | last = Reynolds | first = Lindsay M. | coauthors = Susan M. Cochran, Brian J. Morris, Judith A. Pratt and Gavin P. Reynolds | date = [[March 1]], [[2005]] | title = Chronic phencyclidine administration induces schizophrenia-like changes in ''N''-acetylaspartate and ''N''-acetylaspartylglutamate in rat brain | journal = Schizophrenia Research | volume = 73 | issue = 2-3 | pages = 147-152 | doi = 10.1016/j.schres.2004.02.003 | id = {{PMID|15653257}} | url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=pubmed_AbstractPlus&cmd=Retrieve&db=pubmed&list_uids=15653257&dopt=ExternalLink | accessdate = 2006-09-29}}</ref> and [[hallucinogens]] are particularly linked to the development of psychosis. Anticholinergic drugs ([[atropine]], [[scopolamine]], [[Jimson weed]]), and many [[antihistamine]]s can also induce psychosis at high enough dosages.<ref name=diphenhydramine_trip_therapeutic>{{cite journal | last = Sexton | first = J. D. | coauthors = D. J. Pronchik | year = 1997 | month = September | title = Diphenhydramine-induced psychosis with therapeutic doses | journal = American Journal of Emergency Medicine | volume = 15 | issue = 5 | pages = 548-549 | id = {{PMID|9270406}} | url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=pubmed_AbstractPlus&cmd=Retrieve&db=pubmed&list_uids=9270406&dopt=ExternalLink | accessdate = 2006-09-29}}</ref><ref name=diphenhydramine_trip_supratherapeutic>{{cite journal | last = Lang | first = K. | coauthors = H. Sigusch, and S. Muller | date = [[December 8]], [[1995]] | title = [An anticholinergic syndrome with hallucinatory psychosis after diphenhydramine poisoning] | journal = Deutsche medizinische Wochenschrift | volume = 120 | issue = 49 | pages = 1695-1698 | id = {{PMID|7497894}}}}</ref><ref name=diphenhydramine_poisoning_psychosis>{{cite journal | last = Schreiber | first = W. | coauthors = A. M. Pauls and J. C. Kreig | date = [[February 5]], [[1988]] | title = [Toxic psychosis as an acute manifestation of diphenhydramine poisoning] | journal = Deutsche medizinische Wochenschrift | volume = 113 | issue = 5 | pages = 180-183 | id = {{PMID|3338401}}}}</ref><ref name=Promethazine>{{cite journal | last = Timnak | first = Charles | coauthors = Ondria Gleason | year = 2004 | month = January-February | title = Promethazine-Induced Psychosis in a 16-Year-Old Girl | journal = Psychosomatics | volume = 45 | issue = 1 | pages = 89-90 | id = {{PMID|14709767}} | url = http://psy.psychiatryonline.org/cgi/content/full/45/1/89 | accessdate = 2006-09-29}}</ref>
-Psychotic states occurring after [[Psychoactive drug|drug]] use may be particularly linked to [[drug overdose]], chronic use and drug withdrawal. Certain compounds may be more likely to induce psychosis and some individuals may show greater sensitivity than others. Certain "street" drugs, such as [[cocaine]], [[amphetamine]]s, [[Phencyclidine|PCP]] and [[hallucinogens]] are particularly linked to the development of psychosis. Anticholinergic drugs ([[atropine]], [[scopolamine]], [[Jimson weed]]), and many [[antihistamine]]s can also induce psychosis at high enough dosages.
-Intoxication with drugs that have general depressant effects on the [[central nervous system]] (especially alcohol and barbiturates) tend not to cause psychosis during use, and can actually decrease or lessen the impact of symptoms in some people. Withdrawal from barbiturates and alcohol can be particularly dangerous, however, leading to psychosis or [[delirium]] and other, potentially lethal, withdrawal effects.
+Intoxication with drugs that have general depressant effects on the [[central nervous system]] (especially alcohol and barbiturates) tend not to cause psychosis during use, and can actually decrease or lessen the impact of symptoms in some people. Withdrawal from barbiturates and alcohol can be particularly dangerous, however, leading to psychosis or delirium and other, potentially lethal, withdrawal effects.
 [[Psychological stress]] is also known to contribute to and trigger psychotic states. Both a history of traumatic incidents experienced throughout the life-span, and the recent experience of a stressful event, is thought to contribute to the development of psychosis. Short-lived psychosis triggered by stress is known as [[brief reactive psychosis]].
-Sleep deprivation has been linked to psychosis, although there is little evidence to suggest that it is a major risk factor in the majority of people. Some people experience [[hypnagogia|hypnagogic]] or hypnopompic hallucinations, where unusual sensory experiences or thoughts appear during waking or drifting off to sleep. These are normal sleep phenomena, however, and are not considered signs of psychosis.
+Sleep deprivation has been linked to psychosis,<ref name=sleep_dep1>{{cite journal | last = Sharma | first = Verinder | coauthors = Dwight Mazmanian | year = 2003 | month = April | title = Sleep loss and postpartum psychosis | journal = Bipolar Disorders | volume = 5 | issue = 2 | pages = 98-105 | id = {{PMID|12680898}} | doi = 10.1034/j.1399-5618.2003.00015.x | url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=pubmed_Citation&cmd=Retrieve&db=pubmed&list_uids=12680898&dopt=ExternalLink | accessdate = 2006-09-27}}</ref><ref name=sleep_dep2>{{cite journal | last = Chan-Ob | first = T. | coauthors = V. Boonyanaruthee | year = 1999 | month = September | title = Meditation in association with psychosis | journal = Journal of the Medical Association of Thailand | volume = 82 | issue = 9 | pages = 925-930 | id = {{PMID|10561951}}}}</ref><ref name=sleep_dep3>{{cite journal | last = Devillieres | first = P. | coauthors = M. Opitz, P. Clervoy, and J. Stephany | year = 1996 | month = May-June | title = [Delusion and sleep deprivation] | journal = L'Encéphale | volume = 22 | issue = 3 | pages = 229-231 | id = {{PMID|}}}}</ref> although there is little evidence to suggest that it is a major risk factor in the majority of people. Some people experience [[hypnagogia|hypnagogic]] or hypnopompic hallucinations, where unusual sensory experiences or thoughts appear during waking or drifting off to sleep. These are normal sleep phenomena, however, and are not considered signs of psychosis.
 During the 1960s and 1970s, psychosis was of particular interest to [[counterculture]] critics of mainstream psychiatric practice, who argued that it may simply be another way of constructing reality and is not necessarily a sign of illness. For example, [[R. D. Laing]] argued that psychosis is a symbolic way of expressing concerns in situations where such views may be unwelcome or uncomfortable to the recipients. He went on to say that psychosis could be also seen as a transcendental experience with healing and spiritual aspects. [[Thomas Szasz]] focused on the social implications of labelling people as psychotic; a label he argues unjustly medicalises different views of reality so such unorthodox people can be controlled by society.
@@ Line 33: / Line 45: @@
 ==Psychotic experience==
+{{unreferencedsect}}
-A psychotic episode can be significantly affected by mood. For example, people experiencing a psychotic episode in the context of depression may experience persecutory or self-blaming delusions or hallucinations, while people experiencing a psychotic episode in the context of [[mania]] may form grandiose delusions or have an experience of deep religious significance.
+A psychotic episode can be significantly affected by mood. For example, people experiencing a psychotic episode in the context of depression may experience persecutory or self-blaming delusions or hallucinations, while people experiencing a psychotic episode in the context of mania may form grandiose delusions or have an experience of deep religious significance.
 Although usually distressing and regarded as an illness process, some people who experience psychosis find beneficial aspects and value the experience or revelations that stem from it.
 ===Hallucinations===
-[[Hallucination]]s are defined as sensory perception in the absence of external stimuli. They are different from [[illusions]], which are the misperception of external stimuli. Hallucinations may occur in any of the five senses and take on almost any form, which may include simple sensations (such as lights, colors, tastes, smells) to more meaningful experiences such as seeing and interacting with fully formed animals and people, hearing voices and complex tactile sensations.
+Hallucinations are defined as sensory perception in the absence of external stimuli. They are different from [[illusions]], which are the misperception of external stimuli. Hallucinations may occur in any of the five senses and take on almost any form, which may include simple sensations (such as lights, colors, tastes, smells) to more meaningful experiences such as seeing and interacting with fully formed animals and people, hearing voices and complex tactile sensations.
 Auditory hallucinations, particularly the experience of hearing voices, are a common and often prominent feature of psychosis. Hallucinated voices may talk about, or to the person, and may involve several speakers with distinct personas. Auditory hallucinations tend to be particularly distressing when they are derogatory, commanding or preoccupying. However, the experience of hearing voices need not always be a negative one. Research has shown that the majority of people who hear voices are not in need of psychiatric help.<ref> {{cite web| last = Honig| first = A | authorlink = | coauthors = Romme MA, Ensink BJ, Escher SD, Pennings MH, deVries MW | title = Auditory hallucinations: a comparison between patients and nonpatients | work = Journal of Nervous and Mental Disease | publisher = | date = 1998 | url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=9788642 | format = | doi = | accessdate = 2006-08-19 }}</ref> The [[Hearing Voices Movement]] has subsequently been created to support voice hearers, regardless of whether they are considered to have a mental illness or not.
 ===Delusions and paranoia===
-Psychosis may involve [[delusion|delusional]] or [[paranoia|paranoid]] beliefs. [[Karl Jaspers]] classified psychotic delusions into ''primary'' and ''secondary'' types. Primary delusions are defined as arising out-of-the-blue and not being comprehensible in terms of normal mental processes, whereas secondary delusions may be understood as being influenced by the person's background or current situation (i.e. ethnic or sexual descrimination, religious, superstitious belief).
+Psychosis may involve [[delusion|delusional]] or [[paranoia|paranoid]] beliefs. [[Karl Jaspers]] classified psychotic delusions into ''primary'' and ''secondary'' types. Primary delusions are defined as arising out-of-the-blue and not being comprehensible in terms of normal mental processes, whereas secondary delusions may be understood as being influenced by the person's background or current situation (i.e. ethnic or sexual descrimination, religious, superstitious belief).<ref name=Jaspers>{{cite book | last = Jaspers | first = Karl | authorlink = Karl Jaspers | others = Translated by J. Hoenig & M.W. Hamilton from German | title = Allgemeine Psychopathologie (General Psychopathology) | origyear = 1963 | edition = Reprint edtion | date = 1997-11-27 | publisher = Johns Hopkins University Press | location = Baltimore, Maryland | language = English | id = ISBN 0801857759}}</ref>
 ===Thought disorder===
@@ Line 53: / Line 66: @@
 In some cases, particularly with auditory and visual hallucinations, the patient has good insight, which makes the psychotic experience even more terrifying because the patient realizes that he or she should not be hearing voices, but is.
-==Medical understanding of psychosis==
+==Medical understanding==
+{{unreferencedsect}}
-There are a number of possible causes for psychosis.  Psychosis may be the result of an underlying mental illness such as [[bipolar disorder]] (also known as manic depression) or [[schizophrenia]].  Psychosis may also be triggered or exacerbated by severe mental stress and high doses or chronic use of drugs such as [[amphetamine]]s, [[LSD]], [[Phencyclidine|PCP]], [[cocaine]] or [[scopolamine]]. However, incidence of psychosis resulting from a single administration of any drug is rare, although cases have been reported in the medical literature suggesting a person's sensitivities to new compounds can be unpredictable. Sudden [[withdrawal]] from [[Central nervous system|CNS]] [[depressant]] drugs, such as [[ethanol|alcohol]] and [[benzodiazepines]], may also trigger psychotic episodes. As can be seen from the wide variety of illnesses and conditions in which psychosis has been reported to arise (including, for example, [[AIDS]], [[leprosy]], [[malaria]] and even [[mumps]]) there is no singular cause of a psychotic episode.
+There are a number of possible causes for psychosis.  Psychosis may be the result of an underlying mental illness such as bipolar disorder (also known as manic depression) or schizophrenia.  Psychosis may also be triggered or exacerbated by severe mental stress and high doses or chronic use of drugs such as amphetamines, [[LSD]], [[Phencyclidine|PCP]], [[cocaine]] or [[scopolamine]]. However, incidence of psychosis resulting from a single administration of any drug is rare, although cases have been reported in the medical literature suggesting a person's sensitivities to new compounds can be unpredictable. Sudden [[withdrawal]] from [[Central nervous system|CNS]] [[depressant]] drugs, such as [[ethanol|alcohol]] and [[benzodiazepines]], may also trigger psychotic episodes. As can be seen from the wide variety of illnesses and conditions in which psychosis has been reported to arise (including, for example, [[AIDS]], [[leprosy]], [[malaria]] and even [[mumps]]) there is no singular cause of a psychotic episode.
-The division of the major psychoses into [[manic depression|manic depressive insanity]] (now called [[bipolar disorder]]) and dementia praecox (now called [[schizophrenia]]) was made by [[Emil Kraepelin]], who attempted to create a synthesis of the various mental disorders identified by 19th century [[Psychiatry|psychiatrists]], by grouping diseases together based on classification of common symptoms. Kraepelin used the term 'manic depressive insanity' to describe the whole spectrum of [[mood disorder]]s, in a far wider sense than it is usually used today. In Kraepelin's classification this would include 'unipolar' [[clinical depression]], as well as [[bipolar disorder]] and other mood disorders such as [[cyclothymia]]. These are characterised by problems with mood control and the psychotic episodes appear associated with disturbances in mood, and patients will often have periods of normal functioning between psychotic episodes even without medication. Schizophrenia is characterized by psychotic episodes which appear to be unrelated to disturbances in mood, and most non-medicated patients will show signs of disturbance between psychotic episodes.
+The division of the major psychoses into manic depressive insanity (now called bipolar disorder) and dementia praecox (now called schizophrenia) was made by [[Emil Kraepelin]], who attempted to create a synthesis of the various mental disorders identified by 19th century [[Psychiatry|psychiatrists]], by grouping diseases together based on classification of common symptoms. Kraepelin used the term 'manic depressive insanity' to describe the whole spectrum of [[mood disorder]]s, in a far wider sense than it is usually used today. In Kraepelin's classification this would include 'unipolar' [[clinical depression]], as well as bipolar disorder and other mood disorders such as [[cyclothymia]]. These are characterised by problems with mood control and the psychotic episodes appear associated with disturbances in mood, and patients will often have periods of normal functioning between psychotic episodes even without medication. Schizophrenia is characterized by psychotic episodes which appear to be unrelated to disturbances in mood, and most non-medicated patients will show signs of disturbance between psychotic episodes.
 Psychotic episodes may vary in duration between individuals. In [[brief reactive psychosis]], the psychotic episode is related directly to a specific stressful life event, so patients may spontaneously recover normal functioning within two weeks.<ref> {{cite web| last = Jauch | first = DA | authorlink = | coauthors = Carpenter WT | title = Reactive psychosis. I. Does the pre-DSM-III concept define a third psychosis? | work = Journal of Nervous and Mental Disease | publisher = | date = 1988 | url =
@@ Line 66: / Line 80: @@
  | journal = Clinical Psychology Review| volume = 21| issue = 8| pages = 1125-41| publisher = PubMed| date = 2001| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11702510| doi = | id = PMID 11702510  | accessdate = 2006-08-19 }}</ref> In this view, people who are diagnosed with a psychotic illness may simply be one end of a spectrum where the experiences become particularly intense or distressing (see [[schizotypy]]).
-===Psychosis and brain function===
+===Brain function===
 The first brain image of a person with psychosis was completed as far back as 1935 using a technique called [[pneumoencephalography]]<ref> {{cite journal| last = Moore| first = M T | authorlink = | coauthors = Nathan D, Elliot AR, Laubach C| title = Encephalographic studies in mental disease. | journal = American Journal of Psychiatry| volume = 92| issue = 1| pages = 43-67| publisher = | date = 1935| url = | doi = | id = | accessdate =  }}</ref> (a painful and now obsolete procedure where [[cerebrospinal fluid]] is drained from around the brain and replaced with air to allow the structure of the brain to show up more clearly on an [[X-ray]] picture).
@@ Line 73: / Line 87: @@
 A 2003 study investigating structural changes in the brains of people with psychosis showed there was significant [[grey matter]] reduction in the [[Cerebral cortex|cortex]] of people before and after they became psychotic.<ref> {{cite journal| last = Pantelis | first = C | authorlink = | coauthors = Velakoulis D, McGorry PD, Wood SJ, Suckling J, Phillips, LJ, Yung AR, Bullmore ET, Brewer W, Soulsby B, Desmond, P, McGuire PK | title = Neuroanatomical abnormalities before and after onset of psychosis: a cross-sectional and longitudinal MRI comparison. | journal = Lancet| volume = 25| issue = 361 (9354)| pages = 281-8| publisher = PubMed| date = 2003| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgicmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12559861| doi = | id = PMID 12559861| accessdate = 2006-08-19 }}</ref> Findings such as these have led to debate about whether psychosis is itself [[neurotoxic]] and whether potentially damaging changes to the brain are related to the length of psychotic episode. Recent research has suggested that this is not the case<ref> {{cite journal| last = Ho | first = BC | authorlink = | coauthors = Alicata D, Ward J, Moser DJ, O'Leary DS, Arndt S, Andreasen NC| title = Untreated initial psychosis: relation to cognitive deficits and brain morphology in first-episode schizophrenia.| journal = American Journal of Psychiatry| volume = 160| issue = 1| pages = 142-148| publisher = PubMed| date = 2003| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgicmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12559861| doi = | id = PMID 12505813| accessdate = 2006-08-19 }}</ref> although further investigation is still ongoing.
-Functional brain scans have revealed that the areas of the brain that react to sensory perceptions are active during psychosis. For example, a [[Positron emission tomography|PET]] or [[Functional MRI|fMRI]] scan of a person who claims to be hearing voices may show activation in the auditory cortex, or parts of the brain involved in the perception and understanding of speech.
+Functional brain scans have revealed that the areas of the brain that react to sensory perceptions are active during psychosis. For example, a [[Positron emission tomography|PET]] or [[Functional MRI|fMRI]] scan of a person who claims to be hearing voices may show activation in the auditory cortex, or parts of the brain involved in the perception and understanding of speech.<ref> Copolov DL, Seal ML, Maruff P, Ulusoy R, Wong MT, Tochon-Danguy HJ, Egan GF. (2003) Cortical activation associated with the experience of auditory hallucinations and perception of human speech in schizophrenia: a PET correlation study. ''Psychiatry Res'', 122 (3), 139-52. PMID 12694889. </ref>
-On the other hand, there is not a clear enough psychological definition of [[belief]] to make a comparison between different people particularly valid. Brain imaging studies on delusions have typically relied on correlations of brain activation patterns with the presence of delusional beliefs.
+On the other hand, there is not a clear enough psychological definition of [[belief]] to make a comparison between different people particularly valid. Brain imaging studies on delusions have typically relied on correlations of brain activation patterns with the presence of delusional beliefs.<ref>Bell, V., Halligan, P.W. & Ellis, H.D. (2006) A Cognitive Neuroscience of Belief. In P.W. Halligan & M. Aylward (eds) ''The Power of Belief''. Oxford: Oxford University Press.</ref>
 One clear finding is that persons with a tendency to have psychotic experiences seem to show increased activation in the right hemisphere of the brain.<ref> {{cite journal| last = Lohr | first = JB | authorlink = | coauthors = Caligiuri MP| title = Lateralized hemispheric dysfunction in the major psychotic disorders: historical perspectives and findings from a study of motor asymmetry in older patients.| journal = Schizophrophrenia Research| volume = 30| issue = 27 (2-3)| pages = 191-8| publisher = PubMed| date = 1997| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9416648| doi = | id = PMID 9416648| accessdate = 2006-08-19 }}</ref> This increased level of right hemisphere activation has also been found in healthy people who have high levels of [[paranormal]] beliefs<ref> {{cite journal| last = Pizaagalli | first = D | authorlink = | coauthors = Lehmann D, Gianotti L, Koenig T, Tanaka H, Wackermann J, Brugger P. | title = Brain electric correlates of strong belief in paranormal phenomena: intracerebral EEG source and regional Omega complexity analyses.| journal = Psychiatry Research| volume = 100| issue = 3| pages = 139-154| publisher = PubMed| date = 2000| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11120441| doi = | id = PMID 11120441| accessdate = 2006-08-19 }}</ref> and in people who report [[mystical]] experiences.<ref> {{cite journal| last = Makarec | first = K | authorlink = | coauthors = Persinger, MA | title = Temporal lobe signs: electroencephalographic validity and enhanced scores in special populations.| journal = Perceptual and Motor Skills| volume = 60| issue = 3| pages = 831-842| publisher = PubMed| date = 1985| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=3927256| doi = | id = PMID 3927256| accessdate = 2006-08-19 }}</ref> It also seems to be the case that people who are more creative are also more likely to show a similar pattern of brain activation.<ref>{{cite journal| last = Weinstein | first = S | authorlink = | coauthors = Graves RE | title = Are creativity and schizotypy products of a right hemisphere bias? | journal = Brain and Cognition| volume = 49| issue = 1| pages = 138-151| publisher = PubMed| date = 2002| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=3927256| doi = | id = PMID 12027399 | accessdate = 2006-08-19 }}</ref> Some researchers have been quick to point out that this in no way suggests that paranormal, mystical or creative experiences are in any way ''by themselves'' a symptom of mental illness, as it is still not clear what makes some such experiences beneficial whilst others lead to the impairment or distress of diagnosable mental pathology. However, people who have profoundly different experiences of reality or hold unusual views or opinions have traditionally held a complex role in society, with some being viewed as [[Crank (person)|kook]]s, whilst others are lauded as [[prophet]]s or visionaries.
-Psychosis has been traditionally linked to the [[neurotransmitter]] [[dopamine]]. In particular, the [[dopamine hypothesis of psychosis]] has been influential and states that psychosis results from an overactivity of dopamine function in the brain, particularly in the [[mesolimbic pathway]]. The two major sources of evidence given to support this theory are that dopamine-blocking drugs (i.e. [[antipsychotic]]s) tend to reduce the intensity of psychotic symptoms, and that drugs which boost dopamine activity (such as [[amphetamine]] and [[cocaine]]) can trigger psychosis in some people (see [[amphetamine psychosis]]).
+Psychosis has been traditionally linked to the [[neurotransmitter]] [[dopamine]]. In particular, the [[dopamine hypothesis of psychosis]] has been influential and states that psychosis results from an overactivity of dopamine function in the brain, particularly in the [[mesolimbic pathway]]. The two major sources of evidence given to support this theory are that dopamine-blocking drugs (i.e. [[antipsychotic]]s) tend to reduce the intensity of psychotic symptoms, and that drugs which boost dopamine activity (such as amphetamine and [[cocaine]]) can trigger psychosis in some people (see [[amphetamine psychosis]]).<ref> Kapur S, Mizrahi R, Li M. (2005) From dopamine to salience to psychosis - linking biology, pharmacology and phenomenology of psychosis. ''Schizophr Res'', 79 (1), 59-68. PMID 16005191</ref>
-The connection between dopamine and psychosis is generally believed to be complex.  First of all, while antipsychotic drugs immediately block dopamine receptors, they usually take a week or two to reduce the symptoms of psychosis. Moreover, newer and equally effective antipsychotic drugs actually block slightly less dopamine in the brain than older drugs whilst also affecting [[serotonin]] function, suggesting the 'dopamine hypothesis' is vastly oversimplified.
+The connection between dopamine and psychosis is generally believed to be complex.  First of all, while antipsychotic drugs immediately block dopamine receptors, they usually take a week or two to reduce the symptoms of psychosis. Moreover, newer and equally effective antipsychotic drugs actually block slightly less dopamine in the brain than older drugs whilst also affecting [[serotonin]] function, suggesting the 'dopamine hypothesis' is vastly oversimplified.<ref> Jones, H. M., & Pilowsky, L. S. (2002) Dopamine and antipsychotic drug action revisited. ''British Journal of Psychiatry'', 181, 271-275. PMID 12356650 </ref>
-Psychiatrist [[David Healy]] has criticised pharmaceutical companies for promoting simplified biological theories of mental illness that seem to imply the primacy of pharmaceutical treatments while ignoring social and developmental factors which are known to be important influences in the aetiology of psychosis.<ref>{{cite book| last = Healy| first = David| authorlink = | coauthors = | title = The Creation of Psychopharmacology| publisher = Harvard University Press| date = 2002 | location = Cambridge | url = | doi = | id = ISBN 0-674-00619-4 }}</ref>
+Psychiatrist [[David Healy (psychiatrist)|David Healy]] has criticised pharmaceutical companies for promoting simplified biological theories of mental illness that seem to imply the primacy of pharmaceutical treatments while ignoring social and developmental factors which are known to be important influences in the aetiology of psychosis.<ref>{{cite book| last = Healy| first = David| authorlink = | coauthors = | title = The Creation of Psychopharmacology| publisher = Harvard University Press| date = 2002 | location = Cambridge | url = | doi = | id = ISBN 0-674-00619-4 }}</ref>
 Some theories regard many psychotic symptoms to be a problem with the perception of ownership of internally generated thoughts and experiences.<ref> {{cite journal| last = Blakemore | first = SJ | authorlink = | coauthors = Smith J, Steel R, Johnstone CE, Frith CD | title = The perception of self-produced sensory stimuli in patients with auditory hallucinations and passivity experiences: evidence for a breakdown in self-monitoring. | journal = Psychological Medicine| volume = 30| issue = 5| pages = 1131-9| publisher = PubMed| date = 2000| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12027049| doi = | id = PMID 12027049 | accessdate = 2006-08-19 }}</ref> For example, the experience of hearing voices may arise from internally generated speech that is mislabeled by the psychotic person as coming from an external source.
-===Cannabis and psychosis===
+===Cannabis===
-There is now growing evidence for a small but significant link between [[cannabis]] use and vulnerability to psychosis.<ref name = Deg> {{cite journal| last = Degenhardt | first = L | authorlink = | coauthors = Smith J, Steel R, Johnstone CE, Frith CD | title = Editorial: The link between cannabis use and psychosis: furthering the debate.  | journal = Psychological Medicine| volume = 33| issue = | pages = 3-6| publisher = PubMed| date = 2003| url =  http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12537030| doi = | id = PMID 12537030 | accessdate = 2006-08-19 }}</ref> Some studies indicate that cannabis use correlates with a slight increase in psychotic experience, which may help to trigger full-blown psychosis in some people.<ref name = Deg> {{cite journal| last = Degenhardt | first = L | authorlink = | coauthors = Smith J, Steel R, Johnstone CE, Frith CD | title = Editorial: The link between cannabis use and psychosis: furthering the debate.  | journal = Psychological Medicine| volume = 33| issue = | pages = 3-6| publisher = PubMed| date = 2003| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12537030| doi = | id = PMID 12537030 | accessdate = 2006-08-19 }}</ref> Early studies have been criticized for failing to consider other drugs (such as [[LSD]]) that the participants may also have used before or during the study, as well as other factors such as possible pre-existing mental health issues. However, more recent studies with better controls have still found a small increase in risk for psychosis in cannabis users. It is still not clear whether this is a causal link, and it may be that [[cannabis]] use only increases the chance of psychosis in people already predisposed to it. Additionally, people who are in the process of developing psychosis possibly make greater use of the drug to provide temporary relief to their mental discomfort. The fact that cannabis use has increased over the past few decades, whereas the rate of psychosis has not,<ref> {{cite paper| author = Degenhardt L, Hall W, Lynskey M   | title = Comorbidity between cannabis use and psychosis: Modelling some possible relationships.| version = Technical Report No. 121. | publisher = Sydney: National Drug and Alcohol Research Centre.| date = 2001 | url = http://ndarc.med.unsw.edu.au/NDARCWeb.nsf/resources/TR_18/$file/TR.121.PDF| format = [[PDF]]| accessdate = 2006-08-19 }}</ref> suggests that a direct causal link is unlikely for all users.
+There is growing evidence for a small but significant link between [[cannabis]] use and vulnerability to psychosis.<ref name = Deg> {{cite journal| last = Degenhardt | first = L | authorlink = | coauthors = Smith J, Steel R, Johnstone CE, Frith CD | title = Editorial: The link between cannabis use and psychosis: furthering the debate.  | journal = Psychological Medicine| volume = 33| issue = | pages = 3-6| publisher = PubMed| date = 2003| url =  http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12537030| doi = | id = PMID 12537030 | accessdate = 2006-08-19 }}</ref> Some studies indicate that cannabis use correlates with a slight increase in psychotic experience, which may help trigger full-blown psychosis in some people.<ref name = Deg> {{cite journal| last = Degenhardt | first = L | authorlink = | coauthors = Smith J, Steel R, Johnstone CE, Frith CD | title = Editorial: The link between cannabis use and psychosis: furthering the debate.  | journal = Psychological Medicine| volume = 33| issue = | pages = 3-6| publisher = PubMed| date = 2003| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12537030| doi = | id = PMID 12537030 | accessdate = 2006-08-19 }}</ref> Early studies have been criticized for failing to consider other drugs (such as [[LSD]]) that the participants may also have used before or during the study, as well as other factors such as possible pre-existing mental health issues. However, more recent studies with better controls have still found a small increase in risk for psychosis in cannabis users.  It is not clear whether this is a causal link, and it may be that cannabis use only increases the chance of psychosis in people already predisposed to it. Additionally, people with developing psychosis possibly make greater use of the drug to provide temporary relief to their mental discomfort. The fact that cannabis use has increased over the past few decades, whereas the rate of psychosis has not,<ref> {{cite paper| author = Degenhardt L, Hall W, Lynskey M   | title = Comorbidity between cannabis use and psychosis: Modelling some possible relationships.| version = Technical Report No. 121. | publisher = Sydney: National Drug and Alcohol Research Centre.| date = 2001 | url = http://ndarc.med.unsw.edu.au/NDARCWeb.nsf/resources/TR_18/$file/TR.121.PDF| format = [[PDF]]| accessdate = 2006-08-19 }}</ref> suggests that a direct causal link is unlikely for all users.
-===Non-psychiatric conditions and psychosis===
+===Non-psychiatric conditions===
 Psychosis can be a feature of several diseases, often when the [[brain]] or [[nervous system]] is directly affected. However, the fact that psychosis can occasionally arise in parallel with a number of ailments (including diseases such as [[flu]] or [[mumps]] for example) suggests that a variety of nervous system stressors can lead to a psychotic reaction. Psychosis arising from non-psychiatric conditions is sometimes known as 'secondary psychosis'. The mechanisms by which this happens are still not clear, but the non-specificity of psychosis has led Tsuang and colleagues to argue that "psychosis is the 'fever' of mental illness&mdash;a serious but nonspecific indicator".<ref> {{cite journal| last = Tsuang | first = MT | authorlink = | coauthors = Stone WS, Faraone SV | title = Toward reformulating the diagnosis of schizophrenia.  | journal = American Journal of Psychiatry| volume =157| issue = 7 | pages = 1041-1050| publisher = PubMed| date = 2000| url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10873908| doi = | id = PMID 10873908 | accessdate = 2006-08-19 }}</ref>
+Non-psychiatric conditions which are particularly linked to psychosis include [[brain tumour]],<ref name=Brain_tumor>{{cite journal | last = Lisanby | first = S. H. | coauthors =  C. Kohler, C. L. Swanson, and R. E. Gur | year = 1998 | month = January | title = Psychosis Secondary to Brain Tumor | journal = Seminars in clinical neuropsychiatry | volume = 3 | issue = 1 | pages = 12-22 | id = {{PMID|10085187}} }}</ref> [[dementia with Lewy bodies]],<ref name=DLB>{{cite journal | last = McKeith | first = Ian G. | year = 2002 | month = February | title = Dementia with Lewy bodies | journal = British Journal of Psychiatry | volume = 180 | pages = 144-147 | id = {{PMID|11823325}} | url = http://bjp.rcpsych.org/cgi/content/full/180/2/144 | accessdate = 2006-09-27}}</ref> [[hypoglycemia]],<ref name=hypoglycemia>{{cite online journal | last = Padder | first = Tanveer | coauthors = Aparna Udyawar, Nouman Azhar, and Kamil Jaghab | year = 2005 | month = December | title = Acute Hypoglycemia Presenting as Acute Psychosis | journal = Psychiatry online | url = http://www.priory.com/psych/hypg.htm | accessdate = 2006-09-27}}</ref> [[intoxication]],<ref name=alchohol>{{cite web | url = http://www.emedicine.com/med/topic3113.htm | title = Alcohol-Related Psychosis | accessmonthday = September 27 | accessyear = 2006 | last = Larson | first = Michael | date = 2006-03-30 | work = eMedicine | publisher = WebMD}}</ref> [[multiple sclerosis]],<ref name=multiple_sclerosis>{{es icon}} {{cite journal | last = Rodriguez Gomez | first = Diego | coauthors = Elvira Gonzalez Vazquez and Óscar Perez Carral | date = [[August 16]]-31, [[2005]] | title = Psicosis aguda como inicio de esclerosis multiple / Acute psychosis as the presenting symptom of multiple sclerosis / Psicose aguda como inicio de esclerose multipla | journal = Revista de Neurología | volume = 41 | issue = 4 | pages = 255-256 | id = {{PMID|16075405}} | url = http://www.revneurol.com/LinkOut/formMedLine.asp?Refer=2005320&Revista=RevNeurol | accessdate = 2006-09-27}} </ref> [[Systemic Lupus Erythematosus]],<ref name=Lupus_Psychosis_India>{{cite journal | last = Robert | first = M. | coauthors = R. Sunitha, and N. K. Thulaseedharan | year = 2006 | month = March | title = Neuropsychiatric manifestations systemic lupus erythematosus: A study from South India | journal = Neurology India | volume = 54 | issue = 1 | pages = 75-77 | id = {{PMID|16679649}} | url = http://www.neurologyindia.com/article.asp?issn=0028-3886;year=2006;volume=54;issue=1;spage=75;epage=77;aulast=Robert | accessdate = 2006-09-29 }}</ref> and [[sarcoidosis]].<ref name=Sarcoidosis>{{cite journal | last = Bona | first = Joseph R. | coauthors = Sondralyn M. Fackler, Morris J. Fendley and Charles B. Nemeroff | year = 1998 | month = August | title = Neurosarcoidosis as a Cause of Refractory Psychosis: A Complicated Case Report | journal = American Journal of Psychiatry | volume = 155 | issue = 8 | pages = 1106-1108 | id = {{PMID|9699702}} | url = http://www.ajp.psychiatryonline.org/cgi/content/full/155/8/1106 | accessdate = 2006-09-29 }}</ref>
-There are some non-psychiatric conditions which are particularly linked to psychosis, which may include:
-* [[Brain tumour]]
-* [[Dementia with Lewy bodies]]
-* [[Hypoglycemia]]
-* [[Intoxication]]
-* [[Multiple sclerosis]]
-* [[Systemic Lupus Erythematosus]] (it is one of the 19 types of nervous system involvement in SLE).
-* [[Sarcoidosis]]
-<!--* Etc looking for a good resource on secondary psychosis-->
 ==Treatment==
-As psychosis is not a diagnosis in itself, the treatment of psychosis often depends on what associated condition (such as [[schizophrenia]] or [[bipolar disorder]]) it is thought to be linked to. However, the [[first line treatment]] for psychotic symptoms is usually [[antipsychotic]] medication, and in some cases [[hospitalisation]]. There is also growing evidence that [[cognitive behavior therapy]]<ref> {{cite journal| last = Birchwood | first = M | authorlink = | coauthors = Trower P | title = The future of cognitive-behavioural therapy for psychosis: not a quasi-neuroleptic. | journal = British Journal of Psychiatry | volume = 188 | issue = | pages = 108-108 | publisher = | date = 2006 | url = | doi = | id = PMID 16449695 | accessdate = 2006-08-19 }}</ref> and [[family therapy]]<ref> {{cite journal| last = Haddock | first = G | authorlink = | coauthors = Lewis S | title = Psychological interventions in early psychosis. | journal = Schizophrenia Bulletin | volume = 31 | issue = 3 | pages = 697-704 | publisher = | date = 2005 | url = | doi = | id = PMID 16006594 | accessdate = 2006-08-19 }}</ref> can be an effective way of managing psychotic symptoms.  When other treatments for psychosis are ineffective, [[electroconvulsive therapy]] (ECT) (aka shock treatment) is sometimes utilized to relieve the underlying symptoms of psychosis, such as depression or schizophrenia.
+The treatment of psychosis often depends on what associated diagnosis (such as schizophrenia or bipolar disorder) is thought to be present. However, the [[first line treatment]] for psychotic symptoms is usually [[antipsychotic]] medication, and in some cases [[hospitalisation]]. There is growing evidence that [[cognitive behavior therapy]]<ref> {{cite journal| last = Birchwood | first = M | authorlink = | coauthors = Trower P | title = The future of cognitive-behavioural therapy for psychosis: not a quasi-neuroleptic. | journal = British Journal of Psychiatry | volume = 188 | issue = | pages = 108-108 | publisher = | date = 2006 | url = | doi = | id = PMID 16449695 | accessdate = 2006-08-19 }}</ref> and [[family therapy]]<ref> {{cite journal| last = Haddock | first = G | authorlink = | coauthors = Lewis S | title = Psychological interventions in early psychosis. | journal = Schizophrenia Bulletin | volume = 31 | issue = 3 | pages = 697-704 | publisher = | date = 2005 | url = | doi = | id = PMID 16006594 | accessdate = 2006-08-19 }}</ref> can be effective in managing psychotic symptoms.  When other treatments for psychosis are ineffective, [[electroconvulsive therapy]] (ECT) (aka shock treatment) is sometimes utilized to relieve the underlying symptoms of psychosis, such as depression or schizophrenia.
 ==See also==
-* [[Amphetamine psychosis]]
-* [[Antipsychotic]]
 * [[Apparitional experience]]
-* [[Bipolar disorder]]
-* [[Delusion]]
 * [[Delusional disorder]]
 * [[Monothematic delusions]]
-* [[Dopamine hypothesis of psychosis]]
-* [[Hallucination]]
 * [[Jerusalem syndrome]]
 * [[Clinical Lycanthropy]]
-* [[Neurosis]]
-* [[Paranoia]]
-* [[Psychiatry]]
-* [[Schizophrenia]]
-* [[Schizotypy]]
-* [[Thought disorder]]
 * [[Soteria]]
+'''Personal accounts'''
+* [[The Eden Express]] by [[Mark Vonnegut]]
+* [[James Tilly Matthews]]
+==References==
+<div class="references-small" style="-moz-column-count:2; column-count:2;">
+<references/>
+</div>
 ==Further reading==
-===Medicine===
 *Sims, A. (2002) ''Symptoms in the mind: An introduction to descriptive psychopathology (3rd edition)''. Edinburgh: Elsevier Science Ltd. ISBN 0-7020-2627-1
@@ Line 133: / Line 136: @@
 *[[Philip K. Dick|Dick, P.K.]] (1981) ''[[VALIS]]''. London: Gollancz. [Semi-autobiographical] ISBN 0-679-73446-5
 *[[Kay Redfield Jamison|Jamison, K.R.]] (1995) ''An Unquiet Mind: A Memoir of Moods and Madness''. London: Picador.<br> ISBN 0-679-76330-9
-*[[The Eden Express]] by [[Mark Vonnegut]]
-* Wikipedia entry for [[James Tilly Matthews]]
 *Schreber, D.P. (2000) ''Memoirs of My Nervous Illness''. New York: New York Review of Books. ISBN 0-940322-20-X
 *McLean, R (2003) ''Recovered Not Cured: A Journey Through Schizophrenia''. Allen & Unwin. Australia. ISBN 1-86508-974-5
@@ Line 140: / Line 141: @@
 ==External links==
 * [http://www.mind.org.uk/Information/Booklets/Understanding/Understanding+Psychotic+Experiences.htm Understanding psychotic experiences] from mental health charity [[Mind (charity)|Mind]]
-==References==
-<div class="references-small" style="-moz-column-count:2; column-count:2;">
-<references/>
 {{featured article}}
@@ Line 168: / Line 165: @@
 [[sv:Psykos]]
 [[tr:Psikoz]]
+[[zh:思覺失調]]