In addition to testing for a relationship between externalizing proneness and the FRN, the current study also examined whether P300 amplitude would be reduced in the choice-feedback paradigm in which the FRN is measured. Prior work has consistently demonstrated reduced P300 amplitude in individuals with impulse control problems including alcohol dependence (Polich, Pollock, & Bloom, 1994) and antisocial personality disorder (e.g., Costa et al., 2000), along with disinhibitory personality traits (e.g., Justus, Finn, & Steinmetz, 2001). Recently, Patrick et al. (2006) established a link between reduced P300 and general externalizing proneness, operationalized as the overlap in symptoms among differing DSM disorders (conduct disorder, adult antisocial behavior, alcohol dependence, and drug dependence). These prior studies have focused on P300 response to simple target stimuli (requiring a response) in a visual oddball task, the procedure most commonly used in the P300 literature. The performance monitoring literature has shown that the P300 can also be measured following the presentation of feedback stimuli, and this P300 response appears functionally distinct from the FRN that follows the same stimuli (Frank, Woroch, & Curran, 2005; Yeung
