The Influencing Factors Of Cooperation

Cooperation is an important topic of research in human behavior and also has broad interest beyond academia.However,the influence of individual difference in groups on reciprocal cooperation and the dynamic brain mechanisms of belief updating underlying reciprocal cooperation are still not clear to researchers,partly because most previous studies have relied on observations on cooperative performance and brains from individual-level rather than group-level.Generally,however,successful cooperation can only be established,on the one hand,that depends on the personal characteristics of both parties in the interaction: an individual who tends to cooperate behaves differently when working with different partner with different traits;on the other hand,successive cooperative relationship depends on the chance when the interactive persons believe that their partner would not choose betray;this belief can be updated by observing the other persons’ actual choices.Thus,cooperation is an interactive process to both partners,and individual difference as well as the process of belief updating play very important roles in conditional cooperation.In view of this,it is extremely important to research the influence of individual differences on reciprocal cooperation at the two-person level,and the changes of synchronization between two human brains.Therefore,using the Prisoner’s Dilemma Game(PDG),we collect the behavioral data and get trait scores from questionnaires by self-reports;using the PDG with event-related potential(ERP)hyperscanning,the second study investigates the dynamics of belief updating in a dyad.At the end of each trial,participants were asked if they believed that their opponent would cooperate in the next trial,and their answers functioned as a self-reported index of reciprocal belief.The results of first study suggested that,behaviorally,dyad of male were more likely to cooperate than dyad of female;Lower scores of perspective taking in dyad and higher scores of neuroticism in dyad make contribution to the reciprocal cooperative relationship between two participants;Additionally,the second studyindicates that self-reported index of reciprocal belief shows strong associations with participants’ behavioral choices(cooperate/betray).On the individual level,the amplitudes of the ERP components frontal P3 a and parietal P3 b elicited by the decision outcome were sensitive to belief updating.On the interpersonal level,the between-subject synchronization in P3 b was higher than those in the other conditions when the paired participants confirmed each other’s reciprocal beliefs.Since previous studies have linked the P3 b with memory updating,we suggest that a cooperative relationship is built up when the memory systems(which support belief updating)of two interacting persons reach a high level of coordination.These findings may help interpret how the feeling of trust develops between strangers and explain how conditional cooperation develops between strangers.