Autism and Sex Differences in the Brain

Specific aspects of the autistic brain may also be extremes of typical male neuroanatomy, according to the authors of a "Viewpoint" article in the 4 November 2005 issue of Science.

On a psychological level, males — on average — have a stronger drive to systemize while females generally have a stronger drive to empathize. On a neuroanatomical level, males generally have greater early growth of certain brain regions, and less hemispheric connectivity than females. The "extreme brain male" theory of autism predicts that individuals on the autistic spectrum should have impairments in empathy alongside intact or even above-average systemizing.

The authors also review the evidence suggesting that testosterone and other androgens thought to shape sex differences in the brain may be pushing the autistic brain to develop beyond the typical male.

Daniel B. Kane

7 November 2005