The Cambridge Autism Research Centre researchers claim

Nov 4, 2005 13:36 GMT  ·  By

A study carried out by the Cambridge Autism Research Centre comes to confirm a 60- year-old theory, according to which the brain structure of people with autism is an "exaggeration" of the normal male brain.

According to the researchers, the males have greater early growth of certain brain regions.

In other words, the boys' brain grows at a much faster rate than girls'. For the people with autism, this growth is even more significant.

Another element backing this theory is the abnormal size of the amygdale (a group of nuclei situated in the temporal lobe), which is responsible for the emotional responses.

The researchers say evidence points to exposure to male hormones, such as testosterone, before birth affecting these brain development patterns.

The "extreme male brain" is an exaggeration of the typical male brain, which is stronger at analyzing systems than showing empathy.

Autism is classified as a neurodevelopmental disorder that manifests itself in markedly abnormal social interaction, communication ability, patterns of interests and patterns of behavior.

By definition, autism must manifest delays in "social interaction, language as used in social communication, or symbolic or imaginative play", with "onset prior to age 3 years".