Brain scans reveal clues about Asperger syndrome

Last Updated: 2002-10-17 15:52:15 -0400 (Reuters Health)

By Keith Mulvihill

NEW YORK (Reuters Health) - For the first time, brain scans of people with a type of autism called Asperger syndrome are helping scientists to zero in on abnormalities in brain function that may explain their behavior.

Autism, which affects about 1 in every 500 children, impairs a person's ability to communicate and form relationships with other people. People with Asperger syndrome are relatively high functioning and are not learning-disabled, according to Dr. Declan G. M. Murphy and colleagues at St. George's Hospital Medical School in London. Instead, these individuals tend to have impaired social skills, and also to exhibit obsessive-compulsive type behaviors.

While people with autism are known to have abnormalities in the frontal lobe and other parts of the brain, there has not been any research into whether people with Asperger syndrome have such abnormalities. To investigate, and to find out if abnormalities might be linked to behavior, the UK team performed MRI scans of the brains of 14 people with Asperger syndrome and compared them with scans from 18 healthy people.

Their findings are published in the October issue of the Archives of General Psychiatry.

"We found significant differences in the amount, and connectivity, of nerve cells in the brains of people with Asperger syndrome," Murphy told Reuters Health. "These differences occurred in brain regions which are crucial to understanding human emotions, and in repetitive 'checking' behaviors.

"In addition, degree of biological abnormality was related to severity of symptoms," the researcher added.

These findings demonstrate that people with Asperger syndrome have biological differences in their brains that explain their behavior, noted Murphy, who added, "they aren't simply 'weird.'

"They were born with these differences and they weren't caused by the way they were brought up, but they are caused--most likely--by differences in cell development," Murphy explained.

Murphy notes that the new findings fill a major gap in understanding why people with Asperger syndrome are the way they are.

"Further studies are needed of brain development and aging across the spectrum of people with autistic disorder," the authors conclude.

SOURCE: Archives of General Psychiatry 2002;59:885-891.

Copyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.