Super Memory in Autistic Savants?
Students with Autistic Spectrum Disorder (ASD) can display amazing abilities well beyond their age, yet struggle in simple, everyday tasks. A teacher told me of a 13 year boy who loved going to the principal’s office to work on math and science exams for 17 year olds, but could not dress himself. A fascinating aspect of this polarity is the “special abilities” displayed by some autistic individuals. These abilities far exceed expectations based on their IQ, and in some cases, their special ability exceeds the level reached by experts in the same field. Special abilities are generally found in the domains of music, memorization of lists, three-dimensional drawing, reading (hyperlexia), and calendar and mental calculation.
Of interest is whether their working memory reflects their extraordinary skills. It seems that the memory profile of an autistic savant is much like an individual with ASD without special abilities. If a memory test uses material that is related to their area of expertise, then savants outperform individuals with ASD without special abilities. For example, a savant calculator has a much higher score than ASD non-experts in number-based working memory tasks. Both ASD groups perform similarly in other working memory tasks. When compared with experts, we see a similar pattern. Both savants and experts show superior memory skills compared to their peers with the same IQ level when tested using material from their area of expertise. Studies that have compared memory skills for music in savant musicians with typical musicians reveal that they demonstrate the same sensitivity and awareness of musical dimensions such as rhythm and pitch. Their similar performance in a music memory test suggests that autistic savant musicians and typical musicians use the working memory in a comparable way.
Autistic savants have built up a huge knowledge base that can be used to increase working memory performance in the area of their expertise. In some cases, their expertise and training in one area can also enhance their scores in another area. For example, calendar calculators and savant calculators can achieve phenomenal scores in memory tests using nonsense words. They are able to apply their training in remembering one type of abstract material (dates and numbers) to related things. One explanation is that dates, numbers, and nonsense words are all abstract material and we use similar mechanisms to remember information that is not connected to semantic memory. The bottom line is that autistic savants have superior memory in the area of their expertise, and in some cases in related areas. This enhanced memory performance far exceeds what is expected of their IQ levels. We see that working memory is very different from IQ.
