that has been observed in alcoholics is also observed in HR subjects, and (ii) the same group (HR subjects) shows deficits in both measures (P3 and EROs) during reward processing. Although theta oscillatory activity during reward processing has been studied in healthy individuals [39,44,70] and in alcoholics [49], the present study is the first to examine event-related theta activity during reward processing in a monetary gambling task in subjects who are at high risk for alcoholism. Using the same approach as in our previous studies of reward processing [49,67], the present study also examined current source density (CSD), to analyze the cortical sources of the surface potentials [71] during theta EROs. The study has compared psychometrically assessed impulsivity as well as externizing diagnoses, such as substance use disorders, conduct disorder (CD), antisocial personality disorder (ASPD), attention deficit hyperactivity disorder (ADHD), and oppositional defiant disorder (ODD), between the risk groups (i.e., HR and LR). We expected that HR compared to LR offspring would manifest lower ERO total theta power and decreased CSD activations in both loss and gain conditions, along with increased impulsivity scores and higher prevalence rates of externalizing disorders. Therefore, findings from the current study may further characterize ERO
