Abstract: 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 social dilemma (i.e., a situation where short-term / personal interest is conflict with long-term / group interest). 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 influence 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 sale task as script, a very common task in the organizational context, to investigate individuals’ cooperative behavior during social dilemma. Participants’ PIC was manipulated by setting the move order of participants and their counterparts during the experimental task. 18 part-time postgraduate students participated in the study, but 3 participants were eliminated due to enormous artifacts, thus leaving 15 valid participant included in statistical analyses. During stimulus presentation, the EEG was recorded using a 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 to participants in middle and low PIC conditions, participants in high PIC condition perceived less self-control conflict, considered the “not to share” choice less tempting, used less willpower when chose the “to share” option, perceived higher interpersonal control, assumed the opponent was highly influenced by them, and more believed the opponent would follow their choices. These findings suggested that PIC was successfully manipulated. Second, results of behavioral outcomes found that 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 to 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 partners’ cooperation to achieve a “win-win” outcome. Last, the behavioral outcomes were supported by ERPs results. It was found that compared to 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 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. Specifically, source analysis suggested that right prefrontal cortex and middle frontal gyrus were activated more greatly. In the situation of 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 accumbens, 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 important, such effect was related with the amplitude of P2 and N2. Limitations and contributions were addressed.

Key words: perceived interpersonal control, cooperative behavior, prisoner delimma, event related potential

摘要： 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。行为数据发现：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数据发现：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。说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。

关键词: 人际控制感, 合作行为, 囚徒困境, 事件相关电位