Abnormal brain growth linked to regressive autism in boys

A new study conducted by researchers at the UC Davis MIND Institute links abnormal brain growth in children to a certain form of autism.

According to the study, boys with regressive autism – a form of autism that typically doesn’t begin to manifest until children are 2 years old – have brains six percent larger than children whose brains have developed normally, and children with non-regressive, early onset autism.

Researchers examined 114 children between the ages of 2 and 4 with autism spectrum disorder and compared the results to 66 children without the disorder. The study showed that while abnormal brain and head growth was evident in boys with regressive autism, no such abnormal growth was found in girls.

“The finding that boys with regressive autism show a different form of neuropathology than boys with early onset autism is novel,” said lead author Christine Wu Nordahl, a researcher at the MIND Institute.

“Moreover, when we evaluated girls with autism separately from boys, we found that no girls — regardless of whether they had early onset or regressive autism — had abnormal brain growth.”

The study showed that abnormal head and brain growth was evident in 22% of the males with regressive autism, as opposed to 5% of those with non-regressive autism. Research shows that abnormal increases in head circumference start to appear as early as four months, and can continue on up to 19 months.

The U.S. Center for Disease Control and Prevention says that autism is four times more likely to occur in males than females. This, along with other recent studies of autism in males and females, suggests the pattern of pathology is different between males and females.

via AFP

[Image credit: Aaron Lee (via ABC News)]