Stanford researchers have found the first clear difference in brain functioning between children with attention deficit hyperactivity disorder, or ADHD, and healthy children, a discovery that may lead to more objective ways to diagnose this mysterious brain malfunction.
Researchers estimate that as many as 6 percent of school-aged children suffer from ADHD and require medication with Ritalin or other drugs to allow them to function properly. Critics, however, charge that the drugs are widely overprescribed and are routinely given to children who are merely exuberant, not hyperactive.
In the absence of an objective way to diagnose the disorder, this controversy is likely to continue. If the new findings hold up under further study, however, they offer hope of ending that dispute.
Using a nonintrusive technique called functional magnetic resonance imaging, psychologist John Gabrieli and his colleagues at Stanford were able to show that specific areas of the brain called the basal ganglia are less active in ADHD children than in healthy ones.
They also found the first evidence that Ritalin works differently in children with ADHD, a finding that may lead to the first explanation of why a stimulant seems to have calming properties.
Their studies show that Ritalin increases brain activity in the basal ganglia in hyperactive children, but decreases basal ganglia activity in healthy children, the team reports in today's Proceedings of the National Academy of Sciences.
Pub Date: 11/24/98