Autism and extraordinary ability

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http://www.economist.com/science/displaystory.cfm?story_id=13489714

Autism and extraordinary ability

Genius locus

Apr 16th 2009

From The Economist print edition

THAT genius is unusual goes without saying. But is it so unusual that it

requires the brains of those that possess it to be unusual in others ways, too?

A link between artistic genius on the one hand and schizophrenia and

manic-depression on the other, is widely debated. However another link, between

savant syndrome and autism, is well established. It is, for example, the subject

of films such as " Rain Man " , illustrated above.

A study published this week by Howlin of King's College, London,

reinforces this point. It suggests that as many as 30% of autistic people have

some sort of savant-like capability in areas such as calculation or music.

Moreover, it is widely acknowledged that some of the symptoms associated with

autism, including poor communication skills and an obsession with detail, are

also exhibited by many creative types, particularly in the fields of science,

engineering, music, drawing and painting. Indeed, there is now a cottage

industry in re-interpreting the lives of geniuses in the context of suggestions

that they might belong, or have belonged, on the " autistic spectrum " , as the

range of syndromes that include autistic symptoms is now dubbed.

So what is the link? And can an understanding of it be used to release flashes

of genius in those whose brains are, in the delightfully condescending term used

by researchers in the area, " neurotypical " ? Those were the questions addressed

by papers (one of them Dr Howlin's) published this week in the Philosophical

Transactions of the Royal Society. The society, Britain's premier scientific

club and the oldest scientific body in the world, produces such transactions

from time to time, to allow investigators in particular fields to chew over the

state of the art. The latest edition is the outcome of a conference held jointly

with the British Academy (a similar, though younger, organisation for the

humanities and social sciences) last September.

A spectrum of belief

A standard diagnosis of autism requires three things to be present in an

individual. Two of these three, impairments in social interaction and in

communication with other people, are the results of autists lacking empathy or,

in technical jargon, a " theory of mind " . In other words they cannot, as even

fairly young neurotypicals can, put themselves in the position of another being

and ask themselves what that other is thinking. The third criterion, however, is

that a person has what are known as restrictive and repetitive behaviours and

interests, or RRBI, in the jargon.

Until recently, the feeling among many researchers was that the first two

features were crucial to someone becoming a savant. The idea was that mental

resources which would have been used for interaction and communication could be

redeployed to develop expertise in some arbitrary task. Now, though, that

consensus is shifting. Several of the volume's authors argue that it is the

third feature, RRBI, that permits people to become savants.

Francesca Happé of King's College, London, is one of them. As she observes,

obsessional interests and repetitive behaviours would allow someone to practice,

albeit inadvertently, whichever skill they were obsessed by. Malcolm Gladwell,

in a book called " Outliers " which collated research done on outstanding people,

suggested that anyone could become an expert in anything by practising for

10,000 hours. It would not be hard for an autistic individual to clock up that

level of practice for the sort of skills, such as mathematical puzzles, that

many neurotypicals would rapidly give up on.

Many, but not all. Dr Happé has drawn on a study of almost 13,000 individual

twins to show that childhood talent in fields such as music and art is often

associated with RRBIs, even in those who are not diagnosed as classically

autistic. She speculates that the abilities of savants in areas that

neurotypicals tend to find pointless or boring may result from an ability to see

differences where a neurotypical would see only similarities. As she puts it,

" the child with autism who would happily spend hours spinning coins, or watching

drops of water fall from his fingers, might be considered a connoisseur, seeing

minute differences between events that others regard as pure repetition. "

Simon Baron-Cohen, a doyen of the field who works at Cambridge University, draws

similar conclusions. He suggests the secret of becoming a savant is

" hyper-systematising and hyper-attention to detail " . But he adds sensory

hypersensitivity to the list. His team have shown one example of this using what

is known as the Freiburg visual acuity and contrast test, which asks people to

identify the gap in a letter " c " presented in four different orientations. Those

on the autistic spectrum do significantly better at this than do neurotypicals.

That might help explain Dr Happé's observations about coins and raindrops.

Insight, too, is given by autists themselves. Temple Grandin is a professor of

animal science at Colorado State University. She also writes about her

experience of being autistic. As she describes in the volume, one of the

differences she perceives between her experience and that of most neurotypicals

is that she thinks in images. She says her mind is like an internet search

engine that searches for photographs. To form concepts, she sorts these pictures

into categories. She does not, however, claim that all autistic people think

like this. To the contrary, she describes two other sorts: pattern thinkers who

excel at maths and music, and verbal specialists who are good at talking and

writing, but lack visual skills. The latter might not qualify as autistic under

a traditional diagnosis, but slip into the broader autistic spectrum.

The question of how the autistic brain differs physically from that of

neurotypicals was addressed by Casanova of the University of Louisville,

in Kentucky. Dr Casanova has spent many years dissecting both. His conclusion is

that the main difference is in the structure of the small columns of nerve cells

that are packed together to form the cerebral cortex. The cortical columns of

those on the autistic spectrum are narrower than those of neurotypicals, and

their cells are organised differently.

The upshot of these differences is that the columns in an autistic brain seem to

be more connected than normal with their close neighbours, and less connected

with their distant ones. Though it is an interpretative stretch, that pattern of

connection might reduce a person's ability to generalise (since disparate data

are less easily integrated) and increase his ability to concentrate (by drawing

together similar inputs).

Rain and sunshine

Given such anatomical differences, then, what hope is there for the neurotypical

who would like to be a savant? Some, possibly. There are examples of people

suddenly developing extraordinary skills in painting and music in adult life as

a result of brain damage caused by accidents or strokes. That, perhaps, is too

high a price to pay. But Allan Snyder of the University of Sydney has been able

to induce what looks like a temporary version of this phenomenon using

magnetism.

Dr Snyder argues that savant skills are latent in everyone, but that access to

them is inhibited in non-savants by other neurological processes. He is able to

remove this inhibition using a technique called repetitive transcranial magnetic

stimulation.

Applying a magnetic field to part of the brain disrupts the electrical activity

of the nerve cells for a few seconds. Applying such a field repeatedly can have

effects that last for an hour or so. The technique has been approved for the

treatment of depression, and is being tested against several other conditions,

including Parkinson's disease and migraines. Dr Snyder, however, has found that

stimulating an area called the left anterior temporal lobe improves people's

ability to draw things like animals and faces from memory. It helps them, too,

with other tasks savants do famously well—proofreading, for example, and

estimating the number of objects in a large group, such as a pile of match

sticks. It also reduces " false " memories (savants tend to remember things

literally, rather than constructing a mnemonic narrative and remembering that).

There are, however, examples of people who seem very neurotypical indeed

achieving savant-like skills through sheer diligence. Probably the most famous

is that of London taxi drivers, who must master the Knowledge—ie, the location

of 25,000 streets, and the quickest ways between them—to qualify for a licence.

The expert here is Eleanor Maguire of University College, London, who famously

showed a few years ago that the shape of the hippocampus, a part of the brain

involved in long-term learning, changes in London cabbies. Dr Maguire and her

team have now turned their attention to how cabbies learn the Knowledge.

The prodigious geographical knowledge of the average cabbie is, indeed,

savant-like. But Dr Maguire recently found that it comes at a cost. Cabbies, on

average, are worse than random control subjects and—horror—also worse than bus

drivers, at memory tests such as word-pairing. Surprisingly, that is also true

of their general spatial memory. Nothing comes for nothing, it seems, and genius

has its price.

Savant syndrome, then, is a case where the politically correct euphemism

" differently abled " has real meaning. The conclusion that should be drawn,

perhaps, is not that neurotypicals should attempt to ape savants, but that

savants—even those who are not geniuses—should be welcomed for what they are,

and found a more honoured place in society.