On the one hand, lower ERO theta power during reward processing observed in this study is suggestive of a dysfunctional reward system in HR subjects. On the other hand, since ERO theta activity has been shown to be related to a variety of behavioral, cognitive, and motivational or emotional aspects of human information processing including reward processing [6,7,11,14,30,39,59,60,109–122], and since HR subjects have been shown to have lower ERO power during other cognitive tasks, such as Go/NoGo [65] and visual oddball [66], our finding of lower theta activation in HR subjects may also indicate a generic cognitive deficit in these ‘at risk’ individuals. However, growing evidence for specific dysfunction in reward processing in HR subjects has been demonstrated by electrophysiological [24,26,67] as well as fMRI studies [123,124]. Since the HR subjects showed lower theta power during both loss and gain conditions, it is reasonable to assume that these ‘at risk’ individuals may have difficulty in evaluating the both positive and negative outcomes. Therefore, this finding may indicate blunted monetary outcome salience or deficient neural reward sensitivity in these subjects. This
