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Savant Syndrome: Assessing the Thin Line

mmg's picture

Savant Syndrome: Assessing the Thin Line

Within the realms of normal human functioning itself, the brain is able to produce
marvels, to act as a comprehensive unit, with precision in co-ordination, and it never
ceases to amaze us. Yet, it is when one encounters examples of ‘extraordinary’ human
behaviour – those outside of this realm we operate in, that the human brain seems at
once more mystifying and elusive an entity. Even more intriguing are cases of such
extraordinary behaviour coupled with mild to severe disabled behaviour in other
areas. Such coordinated presence of disability with talent has been seen and recorded
through most of human history - giftedness with marked disability in other areas.

  Savants are the juxtapositions of severe mental handicap and prodigious mental
ability. Daniel Tammet, a 30 year old British national holds the European record for
reciting the number pi to 22,514 digits in five hours and nine minutes. He speaks 11
languages and has created his own language Manti. He is autistic and had epilepsy
and Asperger Syndrome as a child. Tito Mukhopdhyay, a 20 year old Indian was
diagnosed with severe or low-functioning verbal autism as a child. He is an
accomplished writer and has published a set of poetry, prose and philosophical texts
in his book. Kim Peek, the real Rain Man (the inspiration behind the Dustin Hoffman
movie), is a walking search engine, and takes about the same time Google would to
find a piece of information. In his vast memory he has stored over 9000 books, which
he started learning from as early as 18 months old, when they were being read out to
him. However he can’t button his own shirt, has difficulty with abstraction and has
severe developmental disorders. 

Such severe inconsistencies in human behaviour have been noted through history and
are of great interest to researchers and neurobiologists. In ‘The Boy with the
Incredible Brain’ , a documentary about Daniel Tammet, touted one of the 100 living
geniuses of our century, Tammet remarks that the line between profound talent, and
profound disability seems really, a thin one. The question really then is whether this
‘line’ is as thin as it seems, and if so, how or why it has to be so.

The case of savants is an interesting one. They represent the most extreme cases of
gifts (mostly spatial or mathematical) coexisting with deficits (mainly verbal). They
record an IQ of between 40 and 70 and are either autistic or display autistic
symptoms. They are however able to demonstrate other mental feats that are beyond
the spectrum of ‘normal’ not just for their own intelligence level (judged by their IQ)
but for other intelligence levels too.

Different theories to explain such inconsistencies exist. Most of them have to do with
brain structure. Lateralization of brain forms a major part of what seems a promising
explanation. Deficits in the left hemisphere of the brain such as those in language
(typically controlled by the left hemisphere) are compensated for with assets in the
areas controlled by the right hemisphere – spatial and visual skills. Indeed, Tammet
insists that he is able to feel and visualize numbers to a high degree of precision. Six
is an ugly number, pi is beautiful. Being able to picture these numbers in his head in a
certain way enables him to perform elaborate and complicated calculations. Darold A
Treffert, a leading researcher in the area, asserts that the fact that a lot of savants had
premature births seems to fit well with the atypical brain organization theory. The
brains of premature fetuses are unable to undergo a process called pruning (a number
of excess neurons die off) which occurs in late pregnancy. If such brains experience
trauma to the left hemisphere, (different conditions ranging from lack of oxygen
during birth, to the administration of too much oxygen afterward) then these
‘unpruned’ neurons move on to the right hemisphere to compensate for the loss. An
imbalance remains, and strong right hemisphere ability emerges .

A discrepancy exists in that the theory does not work in reverse. That is, not all
autistic individuals with left hemisphere damage have savant skills. A
pnuemoencephalogram study conducted in 1975 found left hemispheric damage in 15
of 17 autistic patients. Only 4 of them had savant skills .

The theory of atypical brain organization put forth earlier is not a lone one. The late
neurologist Norman Geschwind noted that individuals with gifts in areas controlled
by the right hemisphere, such as music, math and art have above-average deficits in
areas controlled by the left hemisphere, such as speech – manifested by delay in the
onset of speech, stuttering and dyslexia. All of these individuals also display a marked
preference for non right handedness.

Geschwind explains much of this using the effect the hormone testosterone on the
developing fetal brain. While reading up handedness for my last paper, I had found
that the effect of testosterone on the developing fetal brain is one of the theories used
to explain non right-handedness. An important point to note here would be that
according to this theory testosterone exposure can cause both Savantism and non right
handedness in certain cases, but in other cases, its influence is limited only to non
right handedness. Not enough research has been done into the area to account for the
difference, but I suppose it would be an extremely interesting area to look into.

The theories discussed so far are all to do with prenatal development or environment.
They hold credibility, since most holders of profound talent begin to display such
talent much before they’ve had the opportunity to hone it. Is prenatal conditions then
that ‘thin line’?

A look at Kim Peek’s brain may give other answers. While his left hemisphere does
show abnormalities, (in keeping with what is already discussed) there are some more
important clues to consider. His brain is missing a corpus callosum – the bundle of
nerves that connect the left hemisphere to the right. He is also missing the anterior and
posterior commissures, which also link the two hemispheres . While we know of split
brain patients and patients of epilepsy that have had their corpus callosum severed as
part of their treatment being able to carry out other normal functions, the combination
of the two factors (hemisphere inequality and absence of the corpus callosum)
presents interests implications. Is the corpus callosum the missing link?

The vast, seemingly endless memory that some savants display appears to be hard to
account for physiologically. Mortimer Mishkin of the National Institute of Mental
Health has proposed ‘different neural circuits for memory, including a higher-level
cortico-limbic circuit for what is generally referred to as explicit, semantic or
cognitive memory, and a lower-level corticostriatal circuit for the more primitive
habit memory referred to as implicit procedural memory.’  Savants seem to possess
memory of the non cognitive habit form. 

Outside of physiological considerations, do environmental and situational factors
account for eccentricities in behavior and talent? Perhaps. Yet, a safe bet would be
that it doesn’t affect as much as pre-natal factors do, because of what we’ve noted.
Most savants show their ‘talents’ at a very early age. Yet a lot of gifted children,
geniuses or prodigies have eccentricities that are shaped by early childhood
experience. There is always the dreaded ‘trade-off’ – acquiring language, social and
daily living skills for the prodigious talents. The case of Nadia, a gifted childhood
artist, who lost her artistic skills after she began receiving formal education, is often

When a team of scientists led by Ramachandran were looking at Daniel Tammet and
assessing his abilities, one of their concerns was that advanced mathematical abilities
can be acquired, and they wanted to check that his abilities of great computation skills
were not acquired. Indeed, children in Japan taught the abacus method can perform
large mathematical operations in a matter of seconds. This however requires large
amounts of practice and training. The difference then lies in innateness and
preparation. Does it, though?

Some researchers vouch for the ‘Rain Man’ in all of us. It is possible that we have
hidden skills that we don’t tap into because we’re a left-brained society. Allan Snyder
and John Mitchell of the Australian National University in Canberra argue that each
of us have savant brain processes within us but that these are overpowered by more
sophisticated conceptual cognition . However, under certain conditions the dormant
memory that lies within each individual, or a certain new skill or ability
‘materializes’. This could be during hypnosis, under the influence of the barbiturate
sodium amytal, which induces relaxation, or brain stimulation during neurosurgery.
At times dreams are also known to provide such insight into the untapped.

So is it that there really is no line between profound talent and profound disability,
that there is a possibility that profound talent lies within each of us, and that we don’t
know of it? Further, if the savant brains can accomplish prodigious tasks even after
some damage, then the idea that there is indeed a lot our (right) brain can do that
we’re unaware of (by being a left brain society) seems more credible. 

Yet, whether this ‘untapped’ knowledge or skill with a lot of normal adult brains is
acquired is uncertain. A study was done in France and Belgium whose results were
published in 2001. The researchers compared the workings of the brain of a layman
and a prodigy while doing mathematical calculations; the difference between the
acquired skill-user and the innate skill-user was that the former relied on typical very
limited span of short-term working memory while the latter seemed to develop a long
term episodic memory by borrowing from other areas of long term memory .
Although the prodigy is not a savant, and thus does not display any disability, is it
possible that this method works for the savant too?

Instances of such gifted people bring up the need to recognize multiple intelligences
as opposed to recognizing a general intelligence in the form of an IQ. The talents of
savants should be recognized and encouraged. The thin line that lies between
profound talent and profound disability seems to be a blurry one. The more I look into
it, the more it becomes a question not of profound disability, but of profound talent,
and its place in all of us. Research in the area could answer not just our questions
about such differences, but also about what lies beneath. The presence of the exact
same external factors does not give the exact results in every individual. There are
disabled people who do not display out of the ordinary talents. There are completely
able individuals, who show tremendous gift and potential. Yet, there are the ones that
manifest both that continue to vex us.



Further Reading
Tammet, Daniel. Born on a Blue Day Inside the Extraordinary Mind of an Autistic
Savant. New York: Free P, 2007.


  The Boy with the Incredible Brain 
  Winner, Ellen. "Uncommon Talents: Gifted Children, Prodigies and Savants."
Scientific American 1998: 32-38. EBSCO. Bryn Mawr College, Bryn Mawr.

   Treffert, Darold A., and Gregory L. Wallace. "Islands of Genius." Scientific
American Mind 2003: 14-23. EBSCO. Bryn Mawr College, Bryn Mawr.
  Treffert, Darold A., and Daniel D. Christensen. "Inside the Mind of a Savant."
Scientific American Mind 2006: 47-55. EBSCO. Bryn Mawr College, Bryn Mawr.

  Treffert, Darold A., and Gregory L. Wallace. "Islands of Genius." Scientific
American Mind 2003: 14-23. EBSCO. Bryn Mawr College, Bryn Mawr.

  Treffert, Darold A., and Gregory L. Wallace. "Islands of Genius." Scientific
American Mind 2003: 14-23. EBSCO. Bryn Mawr College, Bryn Mawr.

  Treffert, Darold A. "Prodigy and Savant Syndrome: Are They Related?" Savant
Syndrome Islands of Genius. Wisconsin Medical Society. 13 Apr. 2009



Dorothy van den Honert's picture


I write hesitantly as a mere teacher of dyslexic students, but back in 1973 I found that there was evidence of something wrong with the corpus callosum in my students. So I evolved an easy trick to teach them to read and spell without having the lesson go through the CC. It seemed miraculous. In a few months of three-times-a-week-tutoring while by-passing the CC, the kids' reading levels jumped three and a half grade levels and they were at least average spellers. I found out later that signals in one direction through the CC go through approximately 100 to 200 milliseconds slower than signals in the opposite direction. This jittery input to the language area causes the dyslexia.

Many of my kids were artistic, but I never noted that they were any less so after they learned to read with their left hemispheres, but I can't prove it. On the other hand there was one boy whose RH must have been in bad shape, because before I started his lessons, he couldn't copy a pentagon or a Necker cube that I drew. Four months after his reading lessons, I tried again, and this time he hesitantly, but accurately, copied both. He went on to college and did nicely. But that is the only evidence I have that stimulating the left side does not necessarily interfere with the activities of the right.

Paul Grobstein's picture

the ‘Rain Man’ in all of us

Among a lot of interesting issues, it is the tradeoff that seems to me most profound.  Perhaps there is indeed a matter of social pressure, but would one choose to have particular abilities if these necessarily meant a lessening of other abilities?  Which abilities are more valued/valuable and why?