SOCIETY FOR NEUROSCIENCE
Fall Meeting, Nov. 7-11
LOS ANGELES -- Scans of brain activity in adults with attention-deficit/hyperactivity disorder (ADHD) are significantly different from scans of adults without ADHD, yet few difference are noted between scans of these two groups once the ADHD patients begin to take the drug Ritalin (methylphenidate), report researchers from Emory University at this week's meeting of the Society for Neuroscience.
The study is the first to evaluate the role of Ritalin on working memory in persons with ADHD.
Brain activity was first recorded using positron emission tomography (PET) in 13 nonmedicated adults with and nine adults without ADHD while they performed a challenging auditory arithmetic task known as the PASAT (Paced Auditory Serial Addition Task). As expected, the persons with ADHD had more difficulty performing the task unmedicated. Researchers noted from the scans that cerebral blood flow was dysfunctional in the ADHD patients - that areas of their brains were over active in some areas and underactive in others during the task. Task-related neural activity among men with ADHD was not noted in the frontal region, an area traditionally associated with working memory, as it was in the normal control subjects, but rather appeared in the PET images to be most concentrated in the brain's cerebellum and basal ganglia, areas associated with more basic motor functioning and attention. But when researchers repeated the test on the same group of adults with ADHD while they were treated with Ritalin (methylphenidate) and compared PET scans to those of the nonpatients, the brain images were remarkably similar, with the exception of the absence of frontal activations in the ADHD group.
"Medication decreased activation, particularly in the cerebellum and basal
ganglia while increasing activation in novel areas," reports first author Julie
Schweitzer, Ph.D., of Emory, referring to the "inappro
Contact: Sarah Goodwin
Emory University Health Sciences Center