Neuropsychological assessment of adult patients with attention-deficit/hyperactivity disorder.

Adults with persistent attention-deficit/hyperactivity disorder (ADHD) may show cognitive deficits as compared to healthy control subjects. The aim of this study was to compare a sample of adult outpatients with ADHD on medication to healthy controls on a comprehensive neuropsychological assessment battery. Thirty adults with ADHD under stable psychopharmacological treatment and 27 healthy controls matched for age, gender, and IQ were assessed with ten tests measuring performance with regard to attention, memory, executive function, and fine motor control. Lower performance in patients as compared to controls was found in tests of verbal and visual memory, speed of visuo-motor search, set shifting, and divided attention. Indicators of response inhibition and simple response speed were less affected. Adults with ADHD show indicators of lowered cognitive performance under medication. These are related more to memory and attention under high mental load than to response inhibition or simple attention or motor performance.