Narrator:       This is Science Today. Normally, when someone is concentrating on a task, their brain's frontal cortex and another region of the brain called the parietal cortex, interact with the visual system to allow one to focus their attention. But Dr. Ron Mangun, a professor of psychology and neurology at the University of California, Davis found there's a functional disconnection in this network in kids with attention deficit hyperactivity disorder, or ADHD.

Mangun:        They were doing some part of it in a different way. They weren't engaging the attentional control system to modulate visual and auditory processing in the way that the typical children did. So, we call it a functional disconnection because the parts of the brain that are controlling attention and the parts in the brain that are being controlled by attention in the visual system are no longer interacting the same way.

Narrator:       This was the first time researchers found direct evidence that brain connectivity is missing in people with ADHD.

Mangun:        We're discovering a brain maker now that correlates with the diagnosis of the disorder.  We could use the information to help with the clinical diagnosis.

Narrator:       For Science Today, I'm Larissa Branin.