Childhood neurodevelopmental disorders, including Autism Spectrum Disorder (ASD), Attention Deficit Hyperactivity Disorder (ADHD) and Obsessive Compulsive Disorder (OCD), are relatively common and affect approximately 15 percent of children.
These three neurodevelopment disorders have many of the same symptoms such as attention problems in ADHD and ASD and repetitive behaviors in ASD and OCD. Though the three have long been studied as separate disorders, they are all genetically similar.
A group of scientists recently published a study in the American Journal of Psychiatry which highlights the biological similarities in brain structure in children with neurodevelopmental disorders. Additionally, the scientists link the shared behavioral symptoms and suggest the potential that “treatments targeting a spectrum of behaviors may be relevant for all three conditions.”
By looking at the brain white matter, which enables communication between different regions of the brain, the researchers found that children with greater white matter impairment also had higher rates of impaired functioning in daily life, regardless of their diagnosis. The researchers looked at impairments in white matter in the main tract of the brain, which connects the right and left hemispheres. They did this in children with either autism, ADHD or OCD, and compared them to healthy children in a control group. The particular white matter tract which they were studying is the largest and is among the first to develop in infancy and into early childhood. By looking at this white matter structure in infancy, scientists can predict mental functioning and behavior which correlates to cognitive tasks in children of pre-school age.
Though the researchers found impairments in brain white matter in children with all three neurodevelopmental disorders compared to healthy children, youth and teens diagnosed with autism and ADHD showed more severe impairments which were also more widespread than children diagnosed with OCD. Despite this, abnormality in the white matter was associated with abnormal adaptive behavioral functioning across all children in the study with a neurodevelopmental disorder. These findings suggest that rather than focusing on treatment for a specific neurodevelopmental diagnosis in children, treatments can likely address multiple conditions because the characteristics among all three diagnoses are overlapping.
Ameis, S.H., Lerch, J.P., Taylor, M.J., Lee, W., Viviano, J.D., … and Anagnostou, E. (2016). A diffusion tensor imaging study in children with ADHD, autism spectrum disorder, OCD, and matched controls: Distinct and non-distinct white matter disruption and dimensional brain-behavior relationships. American Journal of Psychiatry, 173(12), 1213-1222. doi: 10.1176/appi.ajp.2016.15111435