Even if previous studies showed that children who suffer from autism may present a 10% more accelerated brain growth, a recent research finds this fact to be erroneous. Even though the brain of autistic children seems enlarged, this is not due to an accelerated development of the brain, but it is caused by other factors.

A team of researchers from the University Of Washington School Of Medicine investigated the brain of autistic children and compared it to the one of typical children and also to the one of infants with developmental delay. Scientists used the MRI (Magnetic Resonance Imaging) method in order to scan and measure the transverse relaxation (T2) of gray and white matter found in the cortical regions of the subjects' brain. T2 relaxation was used for measuring the temporal progression of brain maturation.

The trial was conducted on the brain of 60 autistic children, 10 children with typical (normal) brain development and 16 children with developmental delay. The findings of the study, published in the 22th August issue of the Neurology journal, showed that children with autism have altered brain anatomy and do not present accelerated brain growth, as previously thought.

What happens is that the brain of autistic children has differences in the gray matter as compared to the brain of children with typical or delayed development. Leader of the study Dr. Stephen Dager explains the results: "One of the more consistent brain findings associated with autism has been enlarged brain size. In contrast to current theories which suggest the enlarged brains are due to accelerated early growth tied to a more advanced stage of brain maturation, gray matter T2 relaxation findings were in the opposite direction. These results suggest that the mechanism or mechanisms responsible for larger brains in autism are different from more rapid growth."

"An important consideration is that our findings point toward a different research strategy to elucidate abnormal mechanisms underlying brain development in autism. These findings suggest altered gray matter cellular structure and/or pathologic brain processes such as inflammation early in the developmental course of autism."