Savant syndrome

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Savant syndrome is a condition in which a person with a mental disability, such as an autism spectrum disorder, demonstrates profound and prodigious capacities or abilities far in excess of what would be considered normal.[1][2][3] People with savant syndrome may have neurodevelopmental disorders, notably autism spectrum disorders, or brain injuries. The most dramatic examples of savant syndrome occur in individuals who score very low on IQ tests, but not always, in some very rare and extreme cases, some people with savant actually had an average to even a higher IQ while demonstrating exceptional skills or brilliance in specific areas, such as rapid calculation, art, memory, or musical ability.[4][5][6][7] Intelligence in one or several areas lacking or without common sense. In spite of the name "syndrome", it is not recognized as a mental disorder nor as part of mental disorder in medical manuals such as the ICD-10[8] or the DSM-IV.[9]

Characteristics[edit]

According to psychiatrist Darold Treffert, almost all savants have prodigious memory which he describes as "very deep, but exceedingly narrow." It is narrow in the sense that savants may exhibit exceptional memory but have difficulty putting it to use. Some individuals with savant syndrome also have a keen sense of priority, which can involve a broad understanding of politics, law, and a conceivably heightened vocabulary.

Savant skills (islands of ability) are usually found in one or more of five major areas: art, musical abilities, calendar calculation, mathematics and spatial skills.[1] The most common kind of autistic savants are the calendrical savants,[10][11] ‘human calendars’ who can calculate the day of the week with speed and usually with accuracy. Memory feats are the second most common savant skill in a survey.[10]

50% of savants have autism; the other 50% often have some other forms of central nervous system injury or disease.[1] Among autistics, 10% have some form of savant abilities.[11]

Mechanism[edit]

Savant syndrome is poorly understood. No widely accepted cognitive theory explains savants' combination of talent and deficit.[12] It has been suggested that individuals with autism are biased towards detail-focused processing and that this cognitive style predisposes individuals either with or without autism to savant talents.[13] Another hypothesis is that savants hyper-systemize, thereby giving an impression of talent. Hyper-systemizing is an extreme state in the empathizing–systemizing theory that classifies people based on their skills in empathizing with others versus systemizing facts about the external world.[14] Also, the attention to detail savants is a consequence of enhanced perception or sensory hypersensitivity in these unique individuals.[14][15] It has also been confirmed that some savants operate by directly accessing low-level, less-processed information that exists in all human brains but is normally unavailable to conscious awareness.[16]

Epidemiology[edit]

There is no agreement about how many people have savant skills. The estimates range from "exceedingly rare"[17] to one in ten people with autism having savant skills in varying degrees.[1] A 2009 British study of 137 parents of autistic children found that 28% believe their offspring met the criteria for a savant skill, defined as a skill or power "at a level that would be unusual even for "normal" people".[18] As many as 50 cases of sudden or acquired savant syndrome have been reported.[19]

Males with savant syndrome outnumber females by roughly 6:1[20]—slightly higher than the sex ratio disparity for autism spectrum disorders, which is 4.3:1.[21] (See also: Epidemiology of autism)

History[edit]

The term idiot savant (French for "learned idiot" or "knowledgeable idiot") was first used to describe the condition in 1887 by John Langdon Down, who is known for his description of Down syndrome. The term "idiot savant" was later described as a misnomer because not all reported cases fit the definition of idiot, originally used for a person with a very severe intellectual disability. The term autistic savant was also used as a diagnosis for this disorder. Like idiot savant, the term autistic savant also became looked at as a misnomer because only one-half of those who were diagnosed at the time with savant syndrome were autistic. Upon realization of the need for accuracy of diagnosis and dignity towards the individual, the term savant syndrome became widely accepted terminology.[1][17]

Society and culture[edit]

Prodigious savants[edit]

A prodigious savant is someone with a skill level equivalent to or greater than that of a prodigy, regardless of any cognitive disability. The most common trait of prodigious savants is their seemingly limitless mnemonic skills, with many having eidetic or photographic memories. Prodigious savants are extremely rare, with fewer than one hundred noted in more than a century of literature on the subject. Treffert estimates that fewer than fifty or so such individuals are alive today.

Notable cases[edit]

The following are well-known people with savant syndrome, noted for their talent in their identified fields:

See also[edit]

References[edit]

  1. ^ a b c d e Treffert, D. A. (2009). "The savant syndrome: An extraordinary condition. A synopsis: Past, present, future". Philosophical Transactions of the Royal Society B: Biological Sciences 364 (1522): 1351–7. doi:10.1098/rstb.2008.0326. PMC 2677584. PMID 19528017. 
  2. ^ Miller, LK (1999). "The savant syndrome: Intellectual impairment and exceptional skill". Psychological Bulletin 125 (1): 31–46. doi:10.1037/0033-2909.125.1.31. PMID 9990844. 
  3. ^ Bolte, S (2004). "Comparing the intelligence profiles of savant and nonsavant individuals with autistic disorder". Intelligence 32 (2): 121. doi:10.1016/j.intell.2003.11.002. 
  4. ^ Psychology in Action Eighth Edition, John Wiley & Sons, Inc. (2007), p. 314. Retrieved 2013-02-12.
  5. ^ Enhanced pitch sensitivity in individuals with autism: A signal detection analysis. Bonnel, A., Mottron, L., Peretz, I., Trudel, M., Gallun, E., & Bonnel, A-M. (2003). Cognitive Neuroscience, 5(2), 226-235.
  6. ^ An explanation for normal and anomalous drawing ability and some implications for research on perception and imagery. McMahon, J. A. (2002). Visual Arts Research, 28(1, Issue55), 38-52.
  7. ^ Numbers and letters: Exploring an autistic savant's unpractised ability. Neurocase, 8(4), 330-337. Pring, L., & Hermelin, B. (2002).
  8. ^ http://priory.com/psych/ICD.htm
  9. ^ "APA Diagnostic Classification DSM-IV-TR". BehaveNet. BehaveNet Inc. Retrieved 13 October 2012. 
  10. ^ a b Saloviita, T.; Ruusila, L.; Ruusila, U. (Aug 2000). "Incidence of Savant Syndrome in Finland.". Percept Mot Skills 91 (1): 120–2. PMID 11011882. 
  11. ^ a b Kennedy DP, Squire LR (2007). "An analysis of calendar performance in two autistic calendar savants.". Learn Mem 14 (8): 533–8. doi:10.1101/lm.653607. PMC PMC1951792. PMID 17686947. 
  12. ^ Pring, Linda (2005). "Savant talent". Developmental Medicine & Child Neurology 47 (7): 500. doi:10.1017/S0012162205000976. 
  13. ^ Happe, F.; Vital, P. (2009). "What aspects of autism predispose to talent?". Philosophical Transactions of the Royal Society B: Biological Sciences 364 (1522): 1369–1375. doi:10.1098/rstb.2008.0332. PMC 2677590. PMID 19528019. Lay summaryThe Economist (April 16, 2009). 
  14. ^ a b Baron-Cohen, S.; Ashwin, E.; Ashwin, C.; Tavassoli, T.; Chakrabarti, B. (2009). "Talent in autism: Hyper-systemizing, hyper-attention to detail and sensory hypersensitivity". Philosophical Transactions of the Royal Society B: Biological Sciences 364 (1522): 1377. doi:10.1098/rstb.2008.0337. 
  15. ^ Mottron, L.; Dawson, M.; Soulieres, I. (2009). "Enhanced perception in savant syndrome: Patterns, structure and creativity". Philosophical Transactions of the Royal Society B: Biological Sciences 364 (1522): 1385–1391. doi:10.1098/rstb.2008.0333. PMC 2677591. PMID 19528021. 
  16. ^ Snyder, A. (2009). "Explaining and inducing savant skills: Privileged access to lower level, less-processed information". Philosophical Transactions of the Royal Society B: Biological Sciences 364 (1522): 1399–1405. doi:10.1098/rstb.2008.0290. PMC 2677578. PMID 19528023. Lay summaryThe Economist (April 16, 2009). 
  17. ^ a b http://www.psy.dmu.ac.uk/drhiles/Savant%20Syndrome.htm[full citation needed]
  18. ^ Howlin, P.; Goode, S.; Hutton, J.; Rutter, M. (2009). "Savant skills in autism: Psychometric approaches and parental reports". Philosophical Transactions of the Royal Society B: Biological Sciences 364 (1522): 1359–1367. doi:10.1098/rstb.2008.0328. PMC 2677586. PMID 19528018. Lay summaryThe Economist (April 16, 2009). 
  19. ^ Yant-Kinney, Monica (2012-08-20). "An artist is born after car crash". The Inquirer (Philadelphia). Retrieved 2012-11-24. 
  20. ^ Treffert, Darold. A Visual Feast
  21. ^ Newschaffer CJ, Croen LA, Daniels J et al. The epidemiology of autism spectrum disorders [PDF]. Annu Rev Public Health. 2007;28:235–58. doi:10.1146/annurev.publhealth.28.021406.144007. PMID 17367287.
  22. ^ a b c d e "Savant Profiles". Wisconsin Medical Society. Retrieved January 10, 2013. 
  23. ^ Treffert, Darold. "Derek Paravicini – A Talent and Love for Music". Wisconsin Medical Society. Retrieved 2007-11-07. 
  24. ^ The Grand Rapids Press. "'Anthony's Prayers': A simple book by Grand Rapids' Anthony Torrone, a grateful survivor". Mlive.com. Retrieved 2012-05-01. 
  25. ^ 'My Lord Savior God helped me survive'
  26. ^ Moore, Charlotte (15 April 2006). "Autistic couple bound to each other - and their art". Guardian. 
  27. ^ "The Childhood and the Life of James Henry Pullen, the Victorian Idiot Savant (1832–1916)" in "History of paediatrics and child health". Archives of Disease in Childhood 88 (90001): 59A. 2003. doi:10.1136/adc.88.suppl_1.A59. 
  28. ^ Treffert, Darold. "James Henry Pullen – Genius of Earlswood Asylum". Wisconsin Medical Society. Archived from the original on 2011. Retrieved 2007-11-07. 
  29. ^ "Matt Savage: The Prodigy", People magazine June 17, 2002
  30. ^ Treffert, Darold. "Matt Savage – A 14-Year-Old Marvelous Musician". Wisconsin Medical Society. Retrieved 2007-11-07. 
  31. ^ Treffert, Darold. "Henriett Seth F. – Rain Girl". Wisconsin Medical Society. Retrieved 2007-11-07. 
  32. ^ "Unlocking the brain's potential". BBC News. 2001-03-10. Retrieved 2007-11-08. 
  33. ^ Horwitz, et al., 1965[verification needed]
  34. ^ Sacks, Oliver, 1985
  35. ^ Featured in a documentary produced by TV network TLC entitled Twin Savants: Flo & Kay Tracey Eagan (2009-05-06). "Twin Savants Fixated on Dick Clark". Jezebel. Retrieved 2009-07-19. 
  36. ^ Lyall, Sarah (February 15, 2007). "Brainman, at Rest in His Oasis". New York Times. 
  37. ^ Brogaard, Berit; Vanni, Simo; Silvanto, Juha (2012). "Seeing mathematics: Perceptual experience and brain activity in acquired synesthesia". Neurocase: 1. doi:10.1080/13554794.2012.701646. 
  38. ^ ABC News: Nightline from ABC News : Man Becomes Genius After Head Injury. http://abcnews.go.com/blogs/health/2012/04/27/real-beautiful-mind-accidental-genius-draws-complex-math-formulas-photos/