the ERN and FRN (i.e., the brain’s response to self-identified performance errors versus the response to negative external feedback) or a product of differing performance conditions in the tasks (flanker versus gambling) within which they are recorded. Evaluating the relationship between the FRN and externalizing proneness across other task conditions that better mirror those in which the ERN is typically investigated would be helpful in ruling out this possibility. For example, it would be of interest to see whether learning tasks (cf. Holroyd and Coles, 2002) in which outcomes inform choices on future trials would show the same result with regard to the FRN. Finally, the basis of the well-documented reduction in delta-P300 amplitude for individuals high in externalizing remains unclear. Future work could selectively investigate processes that may be related to externalizing-related delta-P300 amplitude reductions, or evaluate specific cognitive manipulations or training to assess whether they could ameliorate P300 amplitude deficits.
