Rational choice theory predicts that humans always optimize the expected utility of options when making decisions. However, in decision-making games, humans often punish their opponents even when doing so reduces their own reward. We used the Ultimatum and Dictator games to examine the affective correlates of decision-making. We show that the feedback negativity, an event-related brain potential that originates in the anterior cingulate cortex that has been related to reinforcement learning, predicts the decision to reject unfair offers in the Ultimatum game. Furthermore, the decision to reject is positively related to more negative emotional reactions and to increased autonomic nervous system activity. These findings support the idea that subjective emotional markers guide decision-making and that the anterior cingulate cortex integrates instances of reinforcement and punishment to provide such affective markers.

The model of anterior asymmetry and emotion proposes an asymmetric representation of approach and withdrawal systems in the left and right anterior brain regions. Within this framework, 3 different concepts have been related to anterior asymmetry: affective valence, motivational direction, and behavioral activation. The aim of the present study was an empirical investigation into the relation between anterior cortical activity and questionnaire measures related to the 3 dimensions positive versus negative affect, approach versus withdrawal motivation, and behavioral activation versus inhibition. Subjects with relative greater left than right frontal cortical activity showed higher anger-out scores and lower anger-control scores. These results support the hypothesis that motivational direction is related to frontal asymmetry (approach-left and withdrawal-right). Furthermore, subjects with greater bilateral (left and right) frontal cortical activity showed higher behavioral activation scores. This finding might suggest that behavioral activation is related to approach and withdrawal motivation.

Previous studies have identified a negative potential in the event-related potential (ERP), the error-related negativity (ERN), which is claimed to be triggered by a deviation from a reward expectation. Furthermore, this negativity is related to shifts in risk taking, strategic behavioral adjustments, and inhibition. We used a computer Blackjack gambling task to further examine the process associated with the ERN. Our findings are in line with the view that the ERN process is related to the degree of reward expectation. Furthermore, increased ERN amplitude is associated with the negative evaluation of ongoing decisions, and the amplitude of the ERN is directly related to risk-taking and decision-making behavior. However, the findings suggest that an explanation exclusively based on the deviation from a reward expectation may be insufficient and that the intention of the participants and the importance of a negative event for learning and behavioral change are crucial to the understanding of ERN phenomena.

We assessed the influence of the variables outcome potential, feedback valence, magnitude, and probability on the amplitude of the feedback negativity (FN). Outcome potential was defined as the a priori valence of an upcoming feedback, that is, is there a potential win or potential loss? All these variables have been studied previously, although never together, but the findings have been contradictory. We analyzed the event-related potential (ERP) after feedback presentation in a reinforcement-learning task to examine the effects of all the variables on feedback negativity. Our results show that outcome potential, feedback valence, probability, and magnitude all influence feedback related ERPs. Taken together, the findings suggest that ERPs in the time range of the feedback negativity are primarily driven by positive outcomes (reinforcement) rather than negative outcomes (punishment).