Exercising Self-Control Increases Responsivity to Hedonic and Eudaimonic Rewards.

Abstract

The reward responsivity hypothesis of self-control proposes that, irrespective of self-control success, exercising self-control is aversive and engenders negative affect. To countermand this discomfort, reward-seeking behavior may be amplified after bouts of self-control, bringing individuals back to a mildly positive baseline state. Previous studies indicated that effort-an integral component of self-control-can increase reward responsivity. We sought to test and extend the reward responsivity hypothesis by asking if exercising self-control increases a neural marker of reward responsivity (Reward Positivity) differentially for hedonic rewards or eudaimonic rewards. We instructed participants (N = 114) to complete a speeded reaction time task where they exercised self-control (incongruent Stroop trials) or not (congruent Stroop trials), and then had the opportunity to win money for themselves (hedonic rewards) or a charity (eudaimonic rewards) while EEG was recorded. Consistent with the reward responsivity hypothesis, participants evinced a larger RewP after exercising self-control (vs. not exercising self-control). Participants also showed a larger RewP for hedonic over eudaimonic rewards. Self-control and reward type did not interactively modulate RewP, suggesting that self-control increases the reward responsivity in a domain-general manner. The findings provide a neurophysiological mechanism for the reward responsivity hypothesis of self-control and promise to revitalize the relevant literature.