Savant syndrome (/ˈsævənt,sæˈvɑːnt/SAV-ənt, sə-VAHNT,US also/səˈvɑːnt/sav-AHNT) is a phenomenon where someone demonstrates exceptional aptitude in one domain, such as art or mathematics, despite significant social or intellectual impairment.[1]
Savant syndrome is estimated to affect around one in a million people.[4] The condition affects more males than females, at a ratio of 6:1.[1] The first medical account of the condition was in 1783.[1] It is estimated that between 0.5% and 10% of those with autism have some form of savant abilities.[1][6][7] It is estimated that fewer than one hundred prodigious savants are currently living, with skills so extraordinary that they would be considered spectacular even among unimpaired individuals.[1]
Savant skills are usually found in one or more of five major areas: art, memory, arithmetic, musical abilities, andspatial skills.[1] The most common kinds of savants are calendrical savants,[8][9] "human calendars" who cancalculate the day of the week for any given date with speed and accuracy, orrecall personal memories from any given date. Advanced memory is the key "superpower" in savant abilities.[8]
Acalendrical savant (orcalendar savant) is someone who – despite having anintellectual disability – can name the day of the week of a date, or vice versa, on a limited range of decades or certain millennia.[9][10] The rarity of human calendar calculators is possibly due to the lack of motivation to develop such skills among the general population, although mathematicians havedeveloped algorithms that allow them to obtain similar skills.[10] Calendrical savants, on the other hand, may not be prone to invest in socially engaging skills.[11]
No widely acceptedcognitive 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 theempathizing–systemizing theory that classifies people based on their skills in empathizing with others versus systemizing facts about theexternal world.[14] Also, the attention to detail of savants is a consequence of enhanced perception or sensory hypersensitivity in these unique individuals.[14][15] It has also been hypothesized that some savants operate by directly accessing deep, unfiltered information that exists in all human brains that is not normally available to conscious awareness.[16]
In some cases, savant syndrome can be induced following severe head trauma to the left anteriortemporal lobe.[1] Savant syndrome has been artificially replicated using low-frequencytranscranial magnetic stimulation to temporarily disable this area of the brain.[17]
There are no objectively definitive statistics about how many people have savant skills. The estimates range from "exceedingly rare"[18] 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 children met the criteria for a savant skill, defined as a skill or power "at a level that would be unusual even for 'normal' people".[19] As many as 50 cases of sudden or acquired savant syndrome have been reported.[20][21]
Males diagnosed with savant syndrome outnumber females by roughly 6:1 (inFinland),[22] slightly higher than thesex ratio disparity for autism spectrum disorders of 4.3:1.[23]
The termidiot savant (French for 'learned idiot') was first used to describe the condition in 1887[24] byJohn Langdon Down, who is known for his description ofDown syndrome. Down described approximately ten cases of youth he had known with unusual mental powers, like "verbal adhesion" (eg. memorizing books read once), photographic memory for artistic drawing or model-building or music, autobiographical memory, arithmetic & calendrical calculation, & always knowing the current time down to the minute. Down noted that they were all male, none had a family history of similar talents, and that the extraordinary memory was usually associated with "very great defect of reasoning power".
The termidiot savant was later described as amisnomer because not all reported cases fit the definition of idiot, originally used for a person with a very severeintellectual disability. The termautistic savant [fr] was also used as a description of the disorder. Likeidiot savant, the term came to be considered a misnomer because only half of those who were diagnosed with savant syndrome were autistic. Upon realization of the need for accuracy of diagnosis and dignity towards the individual, the termsavant syndrome became widely accepted terminology.[1][18]
