2.33 PREFRONTAL AND PARIETAL CORRELATES OF COGNITIVE CONTROL RELATED TO THE OUTCOME OF ATTENTION-DEFICIT/HYPERACTIVITY DISORDER DIAGNOSED IN CHILDHOOD

Objectives: The protracted and highly variable development of prefrontal cortex and the cognitive control processes supported by the region have been purported to be a major determinant of the adult outcome of ADHD. This neurodevelopmental model was tested in a prospectively followed sample group of adults ages 21-28 years who were diagnosed with ADHD in childhood. Methods: Twenty-seven adult probands diagnosed with ADHD in childhood and 28 carefully matched comparison subjects performed the stimulus and response conflict task during fMRI. Probands were classified with persistent ADHD (n = 11) or remitted ADHD (n = 16). Behavioral and neural responses to stimulus, response, and combined conflicts were compared in probands and comparison subjects and in probands with persistent and remitted ADHD. Results: Response speed and accuracy for stimulus, response, and combined conflicts did not differ across groups. Orbitofrontal, inferior frontal, and parietal activation was lower in probands than comparison subjects, but only for combined conflicts when demand for cognitive control was highest. Reduced activation for combined conflicts in probands was almost wholly attributable to the persistence of ADHD; orbitofrontal, inferior frontal, anterior cingulate, and parietal activation was lower in probands with persistent ADHD than both probands with remitted ADHD and comparison subjects; however, it did not differ between probands with remitted ADHD and comparison subjects. Conclusions: These results provide the first evidence that inferior prefrontal and superior parietal activation during cognitive control differs as a function of the persistence or remission of ADHD in adulthood, with persistence linked to reduced activation (as seen in children with ADHD) and remission of symptoms associated with activation similar to comparison subjects without a history of ADHD.