Sensory processing sensitivity
Sensory processing sensitivity (SPS), a personality trait, a high measure of which defines a highly sensitive person (HSP), has been described as having hypersensitivity to external stimuli, a greater depth of cognitive processing, and high emotional reactivity. The terms SPS and HSP were coined in the mid-1990s by psychologists Elaine Aron and husband Arthur Aron, with SPS being measured by Aron's Highly Sensitive Person Scale (HSPS) questionnaire. Other researchers have applied various other terms to denote this responsiveness to stimuli that is evidenced in humans and other species.
According to the Arons and colleagues, people with high SPS comprise about 15–20% of the population and are thought to process sensory data more deeply due to the nature of their central nervous system. Although many researchers consistently related high SPS to negative outcomes, Aron and colleagues state that high SPS is a personality trait and not a disorder; other researchers have associated it with increased responsiveness to both positive and negative influences.
Origin and development of the terms
Elaine Aron's 1996 book The Highly Sensitive Person defined a population of people having "increased sensitivity to stimulation" and who "are more aware of subtleties and process information in a deeper, more reflective way." In 1997 Elaine and Arthur Aron formally identified sensory processing sensitivity (SPS), the scientific term for highly sensitive or hypersensitivity, as the defining trait of highly sensitive persons (HSPs). By way of definition, Aron & Aron (1997) wrote that sensory processing here refers not to the sense organs as such, but to what occurs as sensory information is transmitted to or processed in the brain. The trait has been described as "neither flaw nor gift, ... an amplifier of an environment's effects."
Aron's professional journal articles and self-help publications have focused on distinguishing high SPS from socially reticent behavior and disorders with which high SPS can be confused; overcoming the social unacceptability that can cause low self-esteem; and emphasizing the advantages of high SPS to balance the disadvantages emphasized by others.
In 2015 Elizabeth Bernstein wrote in the The Wall Street Journal that HSPs were "having a moment," noting that several hundred research studies had been conducted on topics related to HSPs' high sensitivity, and that a First International Scientific Conference on High Sensitivity or Sensory Processing Sensitivity had been held at the Vrije Universiteit Brussel. By 2015, more than a million copies of The Highly Sensitive Person had been sold.
Attributes, characteristics and prevalence
Boterberg et al. (2016) describe high SPS as a "temperamental or personality trait which is present in some individuals and reflects an increased sensitivity of the central nervous system and a deeper cognitive processing of physical, social and emotional stimuli".
People with high SPS report having a heightened response to stimuli such as pain, caffeine, hunger, and loud noises. According to Boterberg et al., these individuals are "believed to be easily overstimulated by external stimuli because they have a lower perceptual threshold and process stimuli cognitively deeper than most other people." This deeper processing may result in decreased reaction time as more time is spent responding to cues in the environment, and might also contribute to cautious behavior and low risk-taking.
The HSP Scale, initially (1997) a questionnaire designed to measure SPS on a unidimensional scale, was subsequently decomposed into two, three, or four factors or sub-scales. Most components have been associated with traditionally-accepted negative psychological outcomes including high stress levels; being easily overwhelmed; increased rates of depression, anxiety, and symptoms of autism; sleep problems; and more physical health problems; the diathesis-stress model focused on increased vulnerability to negative influences. However, the differential susceptibility theory (DST) and biological sensitivity to context theory (BSCT) and sensory processing sensitivity (SPS) suggest increased plasticity (responsiveness) to both positive and negative influences; and the vantage sensitivity (VS) concept emphasizes increased responsiveness to positive experiences. Smolewska et al. (2006) said that in their research, positive outcomes were more common in individuals with high aesthetic sensitivity, who tend to experience heightened positive emotions in response to rewarding stimuli and more likely to score high on "openness" on the Big Five factors model.
Research in evolutionary biology provides evidence that the trait of SPS can be observed, under various terms, in over 100 nonhuman species, Aron writing that the SPS trait is meant to encompass what personality psychologists have described under various other names. Conversely, Aron has distinguished SPS from what she considers it is not, explicitly distinguishing high SPS from possibly-similar-appearing traits or disorders (such as shyness, sensation-seeking, sensory processing disorder, and autism), and further, that SPS may be a basic variable that may underlie multiple other trait differences (such as introversion versus extraversion).
Within humans and other species, two subpopulations of individuals persistently coexist and consistently display different levels of responsiveness to environmental stimuli; the subpopulations respectively embody "responsive" and "unresponsive" strategies that each have corresponding evolutionary costs and benefits. This observation parallels Aron's assertion that high SPS is not a disorder, but rather a personality trait with attendant advantages and disadvantages.
By 2015 the trait had been documented at various levels of study, including temperament and behavior (personality psychology), brain function and neuronal sensitization, and genetics. For example, genetic studies provide evidence that higher levels of SPS are linked to the serotonin transporter 5-HTTLPR short/short genotype, polymorphisms in dopamine neurotransmitter genes, and the ADRA2b norepinephrine-related gene variant.
HSP Scale score patterns in adults were found to be distributed as a dichotomous categorical variable with a break point between 10% and 35%, with Aron choosing a cut-off of the highest-scoring 20% of individuals to define the HSP category.
Sources and notes
- Booth, Charlotte; Standage, Helen; Fox, Elaine (1 Dec 2015), "Sensory-processing sensitivity moderates the association between childhood experiences and adult life satisfaction" (PDF), Personality and Individual Differences, 87: 24–29, doi:10.1016/j.paid.2015.07.020, archived from the original on May 20, 2016
- Boterberg, Sofie; Warreyn, Petra (2016), "Making sense of it all: The impact of sensory processing sensitivity on daily functioning of children", Personality and Individual Differences, 92: 80–86, doi:10.1016/j.paid.2015.12.022, archived from the original on May 23, 2016
- Wolf, Max; Van Doorn, G. Sander; Weissing, Franz J. (2008). "Evolutionary emergence of responsive and unresponsive personalities" (PDF). PNAS. 105 (41): 15825–15830. doi:10.1073/pnas.0805473105. Archived (PDF) from the original on February 7, 2016. "Such differences in responsiveness (also termed coping style, reactivity, flexibility, plasticity) have been documented in many organisms including ... humans" (n. 15 citing Aron & Aron (1997, SPS) and n. 16 citing Belsky et al. (2007, differential susceptibility)). Boterberg et al. (2016) cites Wolf et al. (2008) for the statement: "research in evolutionary biology provides evidence that the trait of SPS can be observed in over 100 nonhuman species."
- Liss, Miriam; Mailloux, Jennifer; Erchull, Mindy J. (2008), "The relationships between sensory processing sensitivity, alexithymia, autism, depression, and anxiety" (PDF), Personality and Individual Differences, 45 (3): 255–259, doi:10.1016/j.paid.2008.04.009, archived (PDF) from the original on May 23, 2016
- Aron, E.N. (2006). "The Clinical Implications of Jung's Concept of Sensitiveness". Journal of Jungian Theory and Practice. 8: 11–43. Archived from the original (PDF) on January 17, 2016. Discussion re nervous system is, inter alia, in "Prelude to Research" at p. 14.
- Belsky, Jay; Pluess, Michael (2009). "Beyond Diathesis Stress: Differential Susceptibility to Environmental Influences" (PDF). Psychological Bulletin. 135 (6): 885–908. doi:10.1037/a0017376. PMID 19883141. Archived (PDF) from the original on December 7, 2010.
- Boyce, W. Thomas (2016). "Differential Susceptibility of the Developing Brain to Contextual Adversity and Stress". Neuropsychopharmacology Reviews. 41: 141–162. doi:10.1038/npp.2015.294. PMID 26391599. "(T)here is an emerging scientific consensus on how 'sensitivity to context' may be instantiated with an intricate and compelling neuroscience" (p. 149). "... a now substantial corpus of evidence ... documenting differences in susceptibility at the levels of temperament and behavior ("The Highly Sensitive Person at p. 146), neuroendocrine physiology, brain structure and function ("Cortical sensory processing sensitivity" at p. 149), neuronal sensitization and responsivity, and allelic and epigenetic variation within genomic structure" (p. 157).
- Boyce, W. Thomas; Ellis, Bruce J. (2005). "Biological sensitivity to context: I. An evolutionary–developmental theory of the origins and functions of stress reactivity" (PDF). Development and Psychopathology. 17: 271–301. doi:10.1017/S0954579405050145. PMID 16761546. Archived from the original on June 28, 2016. "Aron and Aron (1997, p. 362) provide an important further elucidation of the reactivity construct in their discussion of sensory-processing sensitivity" (p. 286).
- Pluess, Michael; Belsky, Jay (2013). "Vantage Sensitivity: Individual Differences in Response to Positive Experiences" (PDF). Psychological Bulletin. 139 (4): 901–916. doi:10.1037/a0030196. Archived (PDF) from the original on January 26, 2016.
- Kaufman, Scott Barry (May 4, 2015). "Shades of Sensitivity". Scientific American. Archived from the original on December 8, 2015. Kaufman explains Smolewska et al. (2006).
- Madrigal, Alix, "She Writes About a Touchy Subject / Book aims to help sensitive people (WebCite archive), San Francisco Chronicle, July 28, 1997.
- Aron, Elaine; Aron, Arthur (1997). "Sensory-Processing Sensitivity and its Relation to Introversion and Emotionality" (PDF). Journal of Personality and Social Psychology. 73 (2): 345–368. doi:10.1037/0022-35184.108.40.2065. Archived (PDF) from the original on May 13, 2015.
- Bartz, Andrea (July 5, 2011). "Sense and Sensitivity". Psychology Today. Archived from the original on May 12, 2016. Last reviewed: June 9, 2016. "... the double-edged nature of sensitivity. Neither flaw nor gift, it is, rather, an amplifier of an environment's effects."
- Chen, Xinyin; Rubin, Kenneth H.; Sun, Yuerong (1992). "Social Reputation and Peer Relationships in Chinese and Canadian Children: A Cross-cultural Study" (PDF). Child Development. 63: 1336–1343. doi:10.1111/j.1467-8624.1992.tb01698.x. Archived (PDF) from the original on February 4, 2016.
- Aron, E.; Aron, A.; Jagiellowicz, J. (2012). "Sensory processing sensitivity: A review in the light of the evolution of biological responsivity" (PDF). Personality and Social Psychology Review. 16 (3): 262–282. doi:10.1177/1088868311434213. Archived (PDF) from the original on May 13, 2015.
- Aron, E. N.; Aron, A.; Davies, K. (2005). "Adult shyness: The interaction of temperamental sensitivity and an adverse childhood environment" (PDF). Personality and Social Psychology Bulletin. 31: 181–197. doi:10.1177/0146167204271419. Archived (PDF) from the original on July 15, 2014. Note 3 (p. 195) cites Chen et al. (1992) re social and cultural unacceptability adding to environmental stressors.
- Rioux, Charlie; Castellanos-Ryan, Natalie; Parent, Sophie; Bitaro, Frank; Tremblay, Richard E.; Seguin, Jean R. (2016). "Differential susceptibility to environmental influences: Interactions between child temperament and parenting in adolescent alcohol use". Dev Psychopathol. 28 (1): 265–275. doi:10.1017/S0954579415000437. PMC . PMID 26030853. "From a clinical perspective, Aron (2010) adds that while sensitive people may be more vulnerable, sensitivity is not only a liability but also may confer advantages."
- Belsky, J.; Jonassaint, C; Pluess, M; Stanton, M; Brummett, B; Williams, R (2009). "Vulnerability genes or plasticity genes?" (PDF). Molecular Psychiatry. 14: 746–754. doi:10.1038/mp.2009.44. PMC . PMID 19455150. Archived (PDF) from the original on June 6, 2012.
- Bernstein, Elizabeth (May 18, 2015). "Do You Cry Easily? You May Be a 'Highly Sensitive Person'". The Wall Street Journal. Archived from the original on June 1, 2015.
- Lally, Maria (October 12, 2015). "Highly sensitive people: a condition rarely understood". The Telegraph (U.K.). Archived from the original on October 18, 2015.
- Evans, David E.; Rothbart, Mary K. (January 2008). "Temperamental sensitivity: Two constructs or one?" (PDF). Personality and Individual Differences. 44 (1): 108–118. doi:10.1016/j.paid.2007.07.016. Archived (PDF) from the original on February 7, 2016. Negative affectand orienting sensitivity.
- Boterberg et al. (2016): overreaction to stimuli (OS) and depth of processing (DP).
- Smolewska et al. (2006): Aesthetic Sensitivity (AES, having greater awareness of beauty), Low Sensory Threshold (LST, easily unpleasantly aroused by external stimuli), and Ease of Excitation (EOE, easily overwhelmed by stimuli); results showing the (unidimensional) HSP Scale was "a valid and reliable measure of the construct of SPS"). Liss et al. (2008).
- Per Boterberg et al. (2016), a "theoretical redefinition" by E. Aron, Psychotherapy and the Highly Sensitive Person (2010): "DOES" acronym: Depth of processing, Overstimulation, Emotional intensity, Sensory sensitivity.
- Ellis, Bruce J.; Boyce, W. Thomas; Belsky, Jay; Bakermans-Kranenburt, Marian J.; van Ijzendoorn, Marinus H. (2011). "Differential susceptibility to the environment: An evolutionary–neurodevelopmental theory" (PDF). Development and Psychopathology. 23: 7–28. doi:10.1017/S0954579410000611. Archived from the original on July 4, 2016. "DST and BSCT began with a focus on child-developmental processes, whereas SPS started with a focus on cognitive processes in adults" (p. 10).
- Thibodeau, Eric L.; August, Gerald J.; Cicchetti, Dante; Symons, Frank J. (2016). "Application of environmental sensitivity theories in personalized prevention for youth substance abuse: a transdisciplinary translational perspective". Transl Behav Med. 6 (1): 81–89. doi:10.1007/s13142-015-0374-4. PMC . PMID 27012256. "Five distinct but related frameworks comprise ES (environmental sensitivity), including diathesis stress, differential susceptibility theory (DST), sensory processing sensitivity (SPS) [n. 22: A&A 1997], biological sensitivity to context (BSC) [n. 23: Boyce 2005], and vantage sensitivity (VS) [n. 24: Pluess 2013]".
- Smolewska, Kathy A.; McCabe, Scott B.; Woody, Erik Z. (2006). "A psychometric evaluation of the Highly Sensitive Person Scale: The components of sensory-processing sensitivity and their relation to the BIS/BAS and "Big Five"". Personality and Individual Differences. 40 (6): 1269–1279. doi:10.1016/j.paid.2005.09.022. See also Kaufman, Scientific American (2015).
- Paraphrasing Aron and citing Wolf re different names for same or equivalent concepts:
- From "Adult shyness: ..." (2005): weak nervous system (Pavlov), low screening (Mehrabian), augmenting (of stimulation; Petrie), reducing (of evoked potential; Buchsbaum, Haier, & Johnson), reactivity (Strelau), avoidance temperament (Elliot & Thrash), and nondisinhibition or reflectivity (Patterson & Newman), and what child temperament researchers have described as inhibitedness (Kagan), infant (or innate) shyness (Cheek & Buss; Daniels & Plomin), reactivity (Rothbart; Strelau), and threshold of responsiveness (Thomas & Chess).
- From "The Clinical Implications of Jung's Concept of Sensitiveness" (2006): innate sensitiveness (Jung),
- From "Adult shyness: ..." (2005): arousal focus (Feldman), and the physiological differences underlying introversion and extroversion (Eysenck; Stelmack; Stelmack & Geen).
- From Wolf et al. (2008): coping style, reactivity, flexibility, plasticity, and differential susceptibility.
- Paraphrasing Aron re what SPS is not:
- From "'The Power of (Shyness)' and High Sensitivity..." (2012): (re introversion) 30% of HSPs are social extroverts.
- From "Adult shyness: ..." (2005): SPS doesn't inherently possess shyness' fear of negative social evaluations.
- From p. 2 of "The HSP in love" (<=2007): an HSP who is also a High Sensation Seeker will find ways to have novel experiences without taking ill-considered risks.
- From "... A Review... " (2012): SPS is "unrelated to Sensory Processing Disorder"
- From "The Clinical Implications of Jung's Concept of Sensitiveness" (2006): (re autism) HSPs are very aware of social and emotional cues and relate well socially once familiarity is achieved.
- Aron, Elaine N. (February 2, 2012). "Time Magazine: 'The Power of (Shyness)' and High Sensitivity". Psychology Today. Archived from the original on March 13, 2016.
- On or before September 27, 2007. "The Highly Sensitive Person In Love with Elaine Aron". WebMD Live Events Transcript. p. 2. Archived from the original on October 7, 2012.
- Licht, Cecile L.; Mortensen, Erik L.; Knudsen, Gitte M. (2011). "Association between Sensory Processing Sensitivity and the 5-HTTLPR Short/Short Genotype" (PDF). Center for integrated molecular brain imaging. Archived (PDF) from the original on June 6, 2012. ● Licht, C., Mortensen, E. L., & Knudsen, G. M. (2011). "Association between sensory processing sensitivity and the serotonin transporter polymorphism 5-HTTLPR short/short genotype." Biological Psychiatry, 69, supplement for Society of Biological Psychiatry Convention and Annual Meeting, abstract 510.
- Chen, C.; Chen, C.; Moyzis, R.; Stern, H.; He, Q.; Li, H.; Dong, Q. (2011). "Contributions of dopamine-related genes and environmental factors to Highly Sensitive Personality: A multi-step neuronal system-level approach". PLoS ONE. 6: e21636. doi:10.1371/journal.pone.0021636. Archived from the original on February 4, 2016.
- Todd, R. M.; Ehlers, M. R.; Muller, D. J.; Robertson, A.; Palombo, D. J.; Freeman, N.; Levine, B.; Anderson, A. K. (2015). "Neurogenetic Variations in Norepinephrine Availability Enhance Perceptual Vividness" (PDF). The Journal of Neuroscience. 35 (16): 6506–6516. doi:10.1523/JNEUROSCI.4489-14.2015. Archived (PDF) from the original on February 15, 2016. ● Castillo, Stephanie (May 8, 2015). "The Highly Sensitive Person: Emotional Sensitivity May Stem From A Person's Genes, Enhancing The Way They See The World". Medical Daily (IBT Media). Archived from the original on May 11, 2015.