The researchers found that the outer layer of the brain (the cortex) was significantly thinner in people who'd had ADHD when they were young compared to those who hadn't had the disorder. These changes were seen in people who continued to have ADHD symptoms and in those who didn't. However, Castellanos said there was a consistent trend for those who still had symptoms to have an even thinner cortex.
The areas most affected by thinning are regions involved in "top-down control of attention and the regulation of attention," said Castellanos. For example, he explained, the amount of attention you give a task is a complex calculation of what's going on around you; how much noise there is; if something else is moving in the room and so forth. If you hear a loud noise, you're at least momentarily distracted unless you can rationally explain the noise away, such as if you're having construction done. If you can rationally explain the noise away, you can get back to work without further distraction. But, this process doesn't work as well for people with ADHD.
"To me, these kinds of studies are exciting because they get to the real neurobiology of ADHD," said Dr. Sara Hamel, a behavioral/developmental pediatrician at Children's Hospital of Pittsburgh. Hamel said some people still see ADHD as a weakness in personality or as caused by bad parenting, but this study and others like it show that "ADHD is a physiologic phenomenon and a real neurological deficit."
Both experts said that it's important for people to realize that ADHD can be a lifelong condition, and if symptoms persist into adulthood, they shouldn't be ignored.
"It's not your fault. It's something different in the way you're wired, and it's probably inherited," explained Hamel. She recommended both medications and behavioral therapy for people with ADHD.
All rights reserved