DEFICIENT INHIBITORY CONTROL IN ATTENTION-DEFICIT HYPERACTIVITY DISORDER

The purpose of this study was to examine two executive control process es response inhibition and re-engagement of responses after inhibition in children with attention deficit hyperactivity disorder (ADHD). Thi rty-three children with ADHD and 22 normal control children of similar age (7 to 11 years) and mean IQ (107) were tested with the change par adigm. ADHD subgroups were defined by the context in which the ADHD sy mptoms predominated (in the home only; at school only; and in both, i. e., pervasive ADHD), Children with marked oppositional defiant or cond uct disorder were excluded. Children with ADHD exhibited deficits in i nhibitory control and in response re-engagement. Deficits were greates t in pervasive ADHD and, to a lesser extent, in those with ADHD limite d to the school concert. ADHD limited to the home context showed the f east deficit. These results replicate an earlier study that found defi cient inhibitory control in pervasive ADHD and demonstrate that the de ficit in ADHD involves a second aspect of executive control.