Trait Reward Sensitivity Modulates Connectivity with the Temporoparietal Junction and Anterior Insula during Strategic Decision Making

Description: Many real-world decisions happen in social contexts such as negotiations, yet little is understood about how we switch decisions given the possibility of rejection. Past investigations found that activation in areas associated with executive function and reward processing are associated with bargaining decisions. However, it remains unclear how individual differences in trait reward sensitivity may modulate activation and connectivity patterns in social situations. Thus, we used task-based fMRI to examine the relation between reward sensitivity and the neural correlates of bargaining choices. Participants (N = 54) completed the Sensitivity to Punishment (SP)/Sensitivity to Reward (SR) Questionnaire and the Behavioral Inhibition System/Behavioral Activation System questionnaires. Subjects underwent fMRI while performing the Ultimatum and Dictator Games as a proposer and exhibited strategic decisions by offering more in the Ultimatum vs. Dictator Game. Consistent with our hypotheses, we replicated past findings that indicated strategic decisions evoke activation in the dlPFC, specifically in the Inferior Frontal Gyrus (IFG) and the Anterior Insula (AI). Next, we found elevated IFG and AI connectivity with the TPJ (Temporoparietal junction) during strategic decisions in social areas of the brain. Lastly, we explored if the cognitive experience of reward modulated brain responses while making strategic decisions by being fair when there was a threat of punishment versus when there was not a threat of punishment. We found that that the interaction of aberrant reward sensitivity (i.e., people who scored high or low in reward sensitivity) and strategic behavior modulated AI-TPJ connectivity. Overall, our results suggest that IFG and AI connectivity with the TPJ modulated the interaction of aberrant reward sensitivity and strategic behavior.