White Matter in the Brain May Help Explain Autism and ADHD
New research links differences in the brain’s white matter to symptoms of both ADHD and autism spectrum disorder, opening the door to more accurate diagnoses.
September 25, 2017
ADHD and autism spectrum disorders (ASD) often overlap, and some children with ADHD who don’t qualify for an autism diagnosis may still demonstrate autism-like traits — and vice versa. Now, new research has attributed this overlap to similar abnormalities in the white matter of brains with ADHD and ASD, finding that children with abnormal white matter nerve bundles are more likely to demonstrate more severe symptoms of either ADHD or ASD.
Researchers at the NYU School of Medicine examined the brains of 174 children between the ages of 6 and 12. Fifty-five children had been diagnosed with ADHD, and 69 with autism; the remaining 50 were typically developing children who served as controls. The majority of the children in each group were male. All children underwent DTI brain scans to map the white matter in their brains.
The scans revealed that structural abnormalities in the brains’ white matter nerve bundles were associated with more severe symptoms of both ADHD and ASD. The differences were starkest in the corpus callosum, the largest white matter structure in the brain, which is responsible for communication between the brain’s two hemispheres.
These results suggest that ADHD and ASD have shared origins in the brain, researchers said, and may one day open up the possibility for improved diagnostic procedures. Because their symptoms are sometimes similar, each condition is frequently misdiagnosed as the other, resulting in ineffective treatment and wasted time. If the study’s results can be replicated, the authors said, it could eventually lead the way to improved understanding and more accurate diagnoses of ADHD and ASD.
“This would help clinicians when they are evaluating a child who comes in with concerns about one or the other disorder to figure out what comes first,” said Dr. Adriana Di Martino, the study’s senior author. “Trying to dissect what aspects are driving these impairments would be helpful.”
That won’t happen until the white matter differences are more clearly understood, she said, but for now, she’s optimistic.
“It has implications for the clinical approaches, and it has implications for future discoveries,” she said. “We don’t know [the implications] yet. But this type of effort, and the questions we’re asking, will hopefully get others asking those questions as well.”
The study was published earlier in September in JAMA Psychiatry.