Reward Counteracts Conflict Adaptation: Evidence for a Role of Affect in Executive Control

The conflict-adaptation effect has been observed in several executive-control tasks and is thought to reflect an increase in control, driven by experienced conflict. We hypothesized that if this adaptation originates from the aversive quality of conflict, it would be canceled out by a positive, rewarding event. Subjects performed an arrow flanker task with monetary gain or loss as arbitrary feedback between trials. As predicted, we found a reduction in conflict adaptation for trials in which conflict was followed by monetary gain. The strength of this gain-induced modulation was found to depend on subjects' motivation to pursue reward, as measured by the Behavioral Activation System Drive scale. Our findings demonstrate for the first time that the conflict-adaptation effect can be strongly reduced by reward contexts, suggesting that reward and conflict can compensate for each other's effects, probably via changes in dopamine levels.