Idiot savant

Savant syndrome is a condition in which a person with a developmental disability demonstrates profound and prodigious capacities or abilities far in excess of what would be considered normal. 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, while demonstrating exceptional skills or brilliance in specific areas, such as rapid calculation (hypercalculia), art, memory, or musical ability. Although termed a syndrome, it is not recognized as a mental disorder nor as part of a mental disorder in medical manuals such as the ICD-10 or the DSM-5.

Another form of savant syndrome is acquired savant syndrome, in which a person acquires prodigious capabilities or skills following dementia, a head injury or severe blow to the head, or other disturbances. This syndrome is rarer, with a study by Darold Treffert in 2010 showing that in a registry of 319 known savants, only 32 had acquired savant syndrome.

Savant skills are usually found in one or more of five major areas: art, musical abilities, calendar calculation, arithmetic, and spatial skills. The most common kind of autistic savants are calendrical savants, "human calendars" who can calculate the day of the week for any given date with speed and accuracy. Memory feats are the second most common savant skill in a survey.

Approximately half of savants are autistic; the other half often have some form of central nervous system injury or disease. It is estimated that 10% of those with autism have some form of savant abilities.

No widely accepted cognitive theory explains savants' combination of talent and deficit. 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. 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. Also, the attention to detail of savants is a consequence of enhanced perception or sensory hypersensitivity in these unique individuals. It has also been confirmed that some savants operate by directly accessing low-level, less-processed information that exists in all human brains that is not normally available to conscious awareness.

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