Alterations in the functional anatomy of working memory in adult attentiondeficit hyperactivity disorder

Objective: The authors used a functional neuroimaging study with a working memory probe to investigate the pathophysiology of attention deficit hypera ctivity disorder (ADHD). Their goat was to compare regional cerebral blood flow (rCBF) changes related to working memory in adults with and without AD HD. Method: Using [O-15]H2O positron emission tomography (PET) studies, the authors compared the sites of neural activation related to working memory in six adult men diagnosed with ADHD and six healthy men without ADHD who w ere matched in age and general intelligence. Results: Task-related changes in rCBF in the men without ADHD were more prominent in the frontal and temp oral regions, but rCBF changes in men with ADHD were more widespread and pr imarily located in the occipital regions. Conclusions: These data suggest t he use of compensatory mental and neural strategies by subjects with ADHD i n response to a disrupted ability to inhibit attention to nonrelevant stimu li and the use of internalized speech to guide behavior.