Autism & savant syndrome

Daniel Tammet is an autistic savant. He has an amazing ability with numbers. Ask him to multiply 37 to the power of 4 and he will instantly give a total of 1,874,161; or ask him to divide 13 by 97 and he will answer to over 100 decimal places!

Daniel also has the ability to learn an entirely new language—grammar, inflection, and comprehension in one week. Daniel can tell you the first 22,500 digits of pi without a mistake. Daniel is also autistic; he was diagnosed with Asperger syndrome at 25 (by Simon Baron-Cohen, as it happens).

You can watch a TED talk or a number of documentaries on Daniel.

Savant syndrome

Savant syndrome is a rare and extraordinary condition that is present in significantly higher ratios in people with autism. Specifically, it refers to being an “island of genius” in a sea of deficits, as the giftedness contrasts significantly with the person’s overall disability.^[1]The savant syndrome: an extraordinary condition. A synopsis: past, present, future

Prevalence of savant syndrome

Research suggests that while the prevalence in the non-autistic population is less than 1%, about 10–28.5% of autistic people have savant syndrome,^[2]Savant skills in autism: psychometric approaches and parental reports^[3]The savant syndrome: an extraordinary condition. A synopsis: past, present, future and as many as one in three people with autism may possess exceptional abilities. Female savants continue to be relatively few, with a 6:1 male-to-female ratio.^[4]The savant syndrome: an extraordinary condition. A synopsis: past, present, future

Autistic savants vs. non-autistic savants

Research shows a difference in cognitive levels and behaviours (presence of stereotyped and ritualistic) in ‘autistic savants’ as compared to savants of other neurology. In addition, the mean IQ of autistic savants was 72 (non-verbal).^[5]Savant skills in autism: psychometric approaches and parental reports Furthermore, ‘autistic savants’ had a tendency to repetitive behaviour and/or preoccupations with a restricted area of interest.^[6]Savant skills in autism: psychometric approaches and parental reports

Most savants have special abilities in musical, artistic, mathematical or mechanical domains, and the savant skill is always linked to an extraordinary memory. In a study of 5,400 autistic savants the most common savant skills were music (53%), memory (40%), mathematical/calculating skills (25%) and art (19%); 53% had multiple special abilities.^[7]Savant skills in autism: psychometric approaches and parental reports

Left-brain damage/right-brain compensation

One hypothesis of how these prodigious skills appear in autistic people is known as the left-brain damage/right-brain compensation hypothesis. Savant syndrome is known to be associated with right-hemisphere skills, while autistic challenges are most strongly associated with left-hemisphere functions.^[8]Where do Savant Skills Come From? | Scientific American

Savant skills are linked to damage to areas of the left hemisphere, and right hemisphere compensation. Since the left hemisphere shows increased sensitivity to testosterone, men are predispositioned to acquire savant abilities.

But key to the emergence of savant syndrome are growth factors—such as the brain-derived neurotrophic factor (BDNF)—which stimulates growth and differentiation of new neurons and synapses.

They also promote the synaptic communication development of new synaptic relations after neuronal damage.

Read more about savant syndrome here:

Synaptic growth, synesthesia & savant abilities