Modulating activity in the dorsolateral prefrontal cortex alter corruption behavior: A transcranial direct current stimulation study.

Corruption behavior has gained worldwide concern for its great harmfulness to public society. In order to reduce corruption, researchers have carried out numerous studies on corrupt prevention. Researchers found that except for external supervision, the internal factor such as moral judgment also have an impact on corruption behavior. Previous brain imaging and stimulation studies suggested that dorsolateral prefrontal cortex (DLPFC) is critical brain area which integrates emotional and cognitive process of moral judgments. Therefore, in the current study, we applied tDCS (transcranial direct current stimulation) over DLPFC to investigated the modulation effect of cortical excitability on corruption behavior. According to the characteristics of corruption, we designed an incomplete information invest game task based on trust game, then adopted a between-subject design to compare participants' corruption rate and reaction time (RT) among right anodal/left cathodal, left anodal/right cathodal and sham tDCS. The results showed that, in contrast to sham stimulation, left anodal/right cathodal tDCS reduced corruption rate both in high and low entrusted amount while right anodal/left cathodal tDCS only prolonged subjects' reaction time (RT) of dishonest response only in high entrusted amount. A possible explanation for the results of current study is that the left DLPFC is associated with the emotional process, which influenced the moral intuition aspect of moral judgment and reflected in the change of immoral behavior rate. While the right DLPFC is associated with cognitive control, which influenced the moral reasoning aspect of moral judgment and reflected in the change of reaction time. This explanation is also consistent with the Emotion-Evoked Collective Corruption Model and dual process theory of brain function.