The Effects Of Pain And Its Sharing On Individual Prosocial Behavior

Previous studies have shown that physical pain can significantly promote prosocial behavior,such as increased trust in others,and individuals who experience pain together show stronger interpersonal bonding and a greater willingness to cooperate.However,previous studies have rarely separated pain and pain sharing to explore their respective effects on prosocial behavior.Is the increase in prosocial behavior due to pain itself or pain sharing? The issue is unclear.For this reason,this study attempts to discuss the effect of pain and pain sharing on pro-social behavior and its brain mechanism with behavioral and electroencephalogram techniques.In this study,a total of 96 healthy participants were recruited and assigned to physical pain and pain sharing condition(induced by Capsaicin)and control condition(with hand cream),respectively.This study using 3(between-subject factor-group: pain sharing group,pain group,non-pain group)x 3(within-subject factor-amount size: 10,50,100 yuan)mixed experimental design.The experiment consists of two contexts,one is benefit context,another loss context.Thirty minutes after pain induction,dictator game tasks was conducted to measure prosocial behavior by benefit sharing(gain context)and loss bearing ratio(loss context).At the same time,the subjects' empathy,emotional state and interpersonal intimacy were measured to explore the role of these variables in the influence of pain and pain sharing on individual prosocial behavior.The behavioral results showed that whatever gain context or loss context there was no significant difference in prosocial behavior between the three groups.The amount of money has the main effect,the larger the amount,the smaller the proportion of the amount subjects allocated and undertaken.There is no interaction between groups and amounts.The proportion of subjects' allocation(gain context)and bearing(loss context)was divided into four levels(0-20%,30%-40%,50% and above 50%).The analysis results showed that compared with the pain group,the pain sharing group would allocate more 50% of the gain and bear more 50% of the loss,and used fairness principle to a greater extent.Moreover,the interpersonal intimacy of the pain sharing group was also significantly higher than that of the pain group.The event-related potential(ERP)results showed that in the gain context,pain sharing group not pain group in the central and parietal electrodes(CZ,C4,CP4)P300 significantly higher than the control group.Previous studies have shown P300 is related to the individual prosocial motivation,so the pain sharing group may have higher prosocial motivation.While the effect did not emerge under the loss context.Taken together,subjects with pain sharing have a higher level of prosocial motivation in the brain mechanism when distributing benefits,and subjects' higher prosocial behavior is distributing benefits and bearing losses fairly and using the fairness principle to a greater extent.Additionally,Pain sharing increased interpersonal intimacy.This study explored the effect of pain and pain sharing on prosocial behavior and also explored its neural mechanism,which provided more evidences for the effect of pain on prosocial behavior.