Why autism can't find a face

Autistic adults were given brain scans

Close up scans of the brains of autistic adults appear to show why many have problems recognising even familiar faces.

Many appear to perceive faces as if they were inanimate objects - using a completely different part of the brain.

However, it is unclear whether this difference is a key to understanding how autism develops - or simply a physical change brought about by years of actually being autistic.

Many of the symptoms of autism, and closely related conditions such as Asperger's syndrome, involve problems with social interaction.

Difficulty recognising, and interpreting the faces of other people is a key characteristic.

This deficiency is in an area called "theory of mind" by psychiatrists.

The study, carried out at Yale University's Neuroimaging Research Program in Autism, is one of the first to see some physical evidence of the autistic mind working in a different way.

Researchers discovered reduced activity in a part of the cerebral cortex of the brain called the "fusiform gyrus".

This part of the brain is normally associated with the mind's ability to process images of faces.

Instead, there was increased activity in the next-door part of the brain that deals with inanimate, or non-face objects.

"This finding is very compelling since it fits with our clinical experience of autism," said Dr Robert Schultz, the principal researcher.

"Persons with autism and Asperger's have very little interest in people, and our study shows that this disinterest is reflected in the manner in which the visual processing centres are organised in their brains."

Remembering faces

The ability to recognise and remember people by their face is a key skill needed by developing children to form interpersonal relationships.

"The face conveys many important types of information, including a person's age, sex and emotional state.

"Decoding this information is critical to successful functioning within a group."

Dr Tonmoy Sharma, an expert in the use of functional magnetic resonance imaging (fMRI) to examine people with various personality and psychiatric disorders, said that he would be interested in the results of the study once they were fully published.

Functional MRI can measure activity in different parts of the brain by showing blood flow into that area.

The more flow there is, the more activity is taking place.

Dr Sharma said: "It is well known that autistic people have a problem with face perception. This looks like a rational study, but the problem is now how we take that information forward and use it."