Attention-Deficit/Hyperactivity Disorder (ADHD) is the most commonly diagnosed disorder of childhood, yet it is poorly understood. Dual pathway models of ADHD (e.g., Sonuga-Barke, 2003) postulate that both motivational and cognitive control dysfunction are prominent in ADHD, and that both are likely related to dysfunction of dopamine and overlapping thalamo-cortical-basal ganglia loops. Related to this model, there is preliminary evidence that motivational deficits and dysfunction of reward-punishment circuitry mediate cognitive control deficits in this population. In light of these theories and initial studies, it is the goal of the proposed study to employ high-density ERPs to examine the motivational impact of events in children with ADHD using the MFN ERP component, and to comprehensively evaluate, using both behavioral and ERP data, the potentially mediating role of motivation in ADHD-related cognitive control deficits. Specifically, it is predicted that ADHD-related behavioral deficits in cognitive control (i.e., response inhibition and error monitoring) and their ERP correlates (i.e., N2 and ERN) will normalize in the context of external motivators. ? ?