Abstract
Two experiments were conducted to examine how cognitive control is modulated by response-contingent reward (Experiment 1) and response-contingent punishment (Experiment 2). The congruency sequence effect (CSE), which is the reduction of the congruency effect after incongruent trials compared to the effect after congruent trials, was analyzed as an index of cognitive control. In both experiments, response speed and accuracy were enhanced by reward or punishment. However, in Experiment 1, the CSE was not evident during anticipation of large reward, whereas a significant CSE was obtained during anticipation of small reward. In contrast, in Experiment 2, the CSE was equivalent regardless of the magnitude of punishment. Moreover, the magnitude of the congruency effect was greater in large punishment than a small one. These results indicate a discrepancy between appetitive and aversive motivations in modulating cognitive control even though both invigorated motor responses. In appetitive motivation, cognitive control is likely to be biased toward a proactive control mode, whereas reactive control is preferable in aversive motivation, where aversiveness also interferes with cognitive processes.