Brain Imaging May Provide Better Autism Screening
With rates of autism on the rise, scientists are scrambling to learn more about the disorder and its potential causes. Researchers are especially interested in the structures of the brain, and the differences between the brains of people with autism and those who are considered neurotypical. Today, autism spectrum disorder (ASD) is diagnosed by professionals trained to recognize the characteristics of autism, as defined by the latest version of the "The Diagnostic and Statistical Manual IV," known as the DSMIV. A new version of the DSM, the DSM-V, is expected in May 2013.
New studies are trying to determine more precise ways of diagnosing autism. A recent study by Nicholas Lange, Associate Professor of Psychiatry at Harvard Medical School and Director of the Neurostatistics Laboratory at McLean Hospital in Massachusetts, used magnetic resonance imaging (MRI) to attempt to distinguish the brains of male adults subjectively diagnosed with high functioning autism. He found that the way water flows through the brain differed between those with autism and those without, distinguishing 28 out of 30 of the men who had been subjectively diagnosed.
Another study from the Yale School of Medicine, examined the brains of autistic children and their unaffected siblings. In this study, they found patterns of brain activity that were unique to the children with autism. Siblings of people with autism are at higher risk of also having autism, and the fascinating finding of this study is that siblings who showed no behavioral trains of ASD did have similar reduced brain activity. However, the study also showed that certain brain regions of unaffected siblings are overactive, possibly compensating for their genetic risk.
MRI is unlikely to become the primary method of diagnosing autism for at least a few years. It is an expensive option, and more needs to be learned before we can use it as a reliable diagnostic tool. But the potential is huge. Diagnosing a child with autism currently takes hours of assessments, is highly subjective, and cannot be done until a child is around 2 years old. We know that early intervention is the best way to help children with developmental delays, so the earlier a child is diagnosed, the better. By studying children as they grow, we might be able to identify the point in time where their brains start developing differently from their typical peers' brains and start therapies immediately. And what if we could start even before that point? Imagine the implications if we could see signs of autism in the brain shortly after birth.Continued on the next page