Researchers at the University of Toronto have discovered that autism, attention deficit hyperactivity disorder (ADHD) and Obsessive Compulsive Disorder (OCD) all have “disruptions in the structure of the corpus callosum” in the brain. The corpus callosum is a nerve fiber bundle that links the left and right hemispheres of the brain. Results of the study were reported in the July 1, 2016 issue of the American Journal of Psychiatry.
In the study, the researchers examined the brains of 71 children with autism, 31 children with ADHD, 36 children with OCD and 62 “typical” children using diffusion tensor imaging. Diffusion tensor imaging measures the diffusion of water across the long fibers that connect the nerve cells in the brain’s white matter. There were “widespread disruptions” in the white matter structure in the brains of the children with autism and the brains of the children with ADHD. The OCD brains had “fewer alterations” than the autism or ADHD brains. Researchers also noted that the children who had the “least independence on daily tasks” (as assessed by their parents) were found to have the “most significant disruptions in white matter.”
Researchers noted two caveats. There were changes in only a small section of the corpus callosum in the autism, ADHD and OCD brains; therefore, the clinical meaning of the changes is unclear. Secondly, “movement in the scanner” by the children could not be ruled out as affecting the differences in the three groups of children.
Sources: Scientific American August 9, 2016 and Spectrumnews.org August 8, 2016