By Clive Cookson, Science Editor
March 22 1999
The ability of some sufferers of autism to perform seemingly
impossible feats of mental arithmetic at lightning speed may be
latent in all human beings, according to new research.
The remarkable talents of so-called savants in the fields of
art and music may also be present in all people, if only they
could find a way of using them.
Allan Snyder and John Mitchell of the Centre for the Mind at
the Australian National University, Canberra, studied savants,
extremely rare individuals who display extraordinary ability in
arithmetic, art or music but lack normal social skills. Most savants
are autistic, like Joseph who inspired the film Rain Man
Examples include the ability to multiply, factor and divide
numbers of six digits and more in a matter of seconds or to specify
a number of objects above 100 at a glance.
One explanation is that savants practise obsessively in a narrow
range of mental activities. The other is that specific parts of
their brains are exceptionally well developed.
In the Royal Society's journa1 Proceedings: Biological Sciences.
Professors Snyder and Mitcbell dismiss both theories. They say
most savant skills appear spontaneously in young autistlc children
- for example, three-year old Nadia who drew horses from memory
with astonishing lifelike perspectlve and without going through
the usual scribbling stage - and practising does not improve them.
There is no evidence of unusual brain development in savants.
The scientists believe that everyone has the mental capacity
to calculate or draw like a savant but a barrier of higher-level
concepts normally blocks access to it. Savants are not distracted
in this way, so they can recognise underlying mathematical patterns
or draw almost photographic images.
For a savant, finding prime numbers is like working in a native
mathematical language, the professors say. For the rest of us,
it is like learning a second language.
Unfortunately, they cannot yet answer two key questions. What
is the primary function of the brain's ultra-fast arithmetical
capacity? And how can we all make use of it?
Professor Snyder guesses that its ultimate purpose is to enable
the bratn to divide up space and time with great accuracy when
processing information.
He believes it may be possible to gain access by "altered states
of consciousness" - perhaps through mind-altering drugs or meditation.
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