人际控制感对合作行为的影响:一项囚徒困境的ERPs研究

The Effect of Perceived Interpersonal Control on Cooperation Behavior: An ERP Investigation Using the Prisoner's Dilemma Game

社会困境中的合作行为是通过抑制个体利益最大化的诱惑从而满足集体利益最大化的过程。研究采用囚徒困境游戏范式考察个体的合作行为,通过设置决策顺序操控人际控制感的高低,利用ERPs技术探讨了人际控制感影响合作行为的神经机制。行为结果发现:高人际控制感条件下个体做出合作行为的频率显著高于低人际控制感。ERPs结果发现:个体在高人际控制感条件下博弈时顶枕区所诱发的P2波幅更小,且右侧额区所诱发的N2波幅也更小。这表明被试在高人际控制感条件下感知到的不确定性更小,冲突控制水平更高,从而更能抑制利己诱惑,表现出更多的合作行为。

Cooperative behavior refers to a prosocial act that one makes to override his / her optimized interest to maximize the benefit of a group. One is required to sacrifice his / her benefit in order to behave cooperatively, thus leading to the occurrence of a social dilemma. Perceived interpersonal control （PIC） is defined as a subjective perception of controlling relationship in interpersonal processes. Previous studies have found that PIC is a factor that has influences on one＇s cooperative behavior. To be more specific, it is demonstrated that high PIC promotes cooperative behavior, but the underlying neural mechanism receives little research. Hence, this study mainly focuses on the electrophysiological mechanisms of the effect of PIC on cooperative behavior. In line with the limited repetitive prisoner dilemma game, we designed a resource-sharing game task using the sale task as script, a very common task in the organizational context, to investigate individuals＇ cooperative behavior in a social dilemma. Participants＇ PIC was manipulated by setting their move order and their counterparts during the experimental task. 15 part-time postgraduate students participated in the study. During the stimulus presentation, their EEG was recorded using an amplifier （Brain Product） from a 64 electrodes of the international 10-20 system. First, we employed ANOVA to examine whether the manipulation of PIC was successful. Results indicated that compared with the participants in the middle and low PIC conditions, the participants in the high PIC condition perceived less self-control conflicts, considered the ＂not to share＂ choice as less tempting, used less willpower when choosing the ＂to share＂ option, perceived higher interpersonal control, assumed that the opponent was highly influenced by them, and more believed that the opponent would follow their choices. These findings suggested that PIC was successfully manipulated. Second, results of behavioral outcomes found that the participants with high PIC spent less time making a decision and had higher cooperation rate. These results were consistent with previous ones and suggest that compared with the low and middle levels of PIC, participants with high PIC felt less self-control conflict, and believed their decisions would have more impact on the final decision, therefore promoting their partners＇ cooperation to achieve a ＂win-win＂ outcome. Last, the behavioral outcomes were supported by ERPs results. It was found that compared with the low PIC condition, the amplitudes of P2 and N2 were lower for people who were performing prisoner＇s game with high PIC. Regression analysis further showed that proportion of cooperation was positively and negatively related to N2 and P2, respectively. This suggested that the influence of high PIC on cooperative behavior on ERPs level was reflected in the decrease in the perception of uncertainty and the increase in conflict inhibition. In the situation of a social dilemma, when individuals were faced with temptation （e.g., short-term rewards）, the nucleus accumbens, a neural basis responsible for reward, was activated. If prefrontal cortex at this moment succeeded in regulating the activation of nucleus aeeumbens, then people were more likely to inhibit their impulse, thus promoting their cooperative behavior. The current findings suggested that people high in PIC were more willing to cooperate. More importantly, such an effect was related to the amplitude of P2 and N2.