Genetic variation in dopamine moderates neural response during reward anticipation and delivery: evidence from event-related potentials

Neuroimaging studies have found moderating effects of dopamine genes during both the anticipation and delivery of rewards, particularly the catechol-O-methyltransferase (COMT) genotype. Event-related potential studies, meanwhile, have focused on the stimulus-preceding negativity (SPN) and the feedback negativity (FN) during reward anticipation and delivery, respectively. In anticipation of uncertain outcomes, we observed an increased SPN among Met homozygotes. We also observed an increased FN among Met homozygotes in response to outcome delivery, an effect that was driven primarily by an increased response to monetary gains. The COMT genotype moderates event-related potential responses during both the anticipation and delivery of uncertain reward, suggesting that the SPN and FN are sensitive to dopaminergically mediated and reward-related neural activity.