School of Psychology, Guizhou Normal University, Intersection of Siya Road and Dongqing Road, Huaxi District, Guiyang, Guizhou, China.
School of Psychology, South China Normal University, 55 West Zhongshan Avenue, Tianhe District, Guangzhou, Guangdong, China.
Behav Brain Res. 2025 Jan 5;476:115256. doi: 10.1016/j.bbr.2024.115256. Epub 2024 Sep 21.
Third-party punishment (TPP) is the punishment that an individual executes on a violator as a third party or observer to maintain social norms. Many studies have provided insights into the neural mechanisms of third-party punishment in group environments. Still, only some studies have focused on the neural mechanisms of third-party punishment in different group sizes. This study used EEG analysis to explore the effects of group size on third-party punishment and its neural activity characteristics from the context of gain and loss. The results show that the punishment rate and amount of the third party in the small group size and loss context were significantly higher than that in the large group size and gain context. EEG results showed that third-party punishment in small groups induced greater P2 than in large groups. In the loss context, the third-party punishment in the large group size induced more negative LNP and activated more theta band activation than in the small group. The results showed that the motivation of the third party to seek a positive reputation in the small size exceeds the balance of its economic interests and tends to punish the violator for maintaining fair norms. The loss context plays a promoting role in this process. However, in the large size, the third-party consideration of its interests was stronger than the willingness to maintain social norms. This study provided neuroscientific evidence for third-party punishment to maintain fair norms in a group environment and further explanations from neuroscience for understanding Indirect Reciprocity Theory.
第三方惩罚（TPP）是指个人作为第三方或观察者对违反者执行的惩罚，以维护社会规范。许多研究已经深入了解了群体环境中第三方惩罚的神经机制。然而，只有一些研究关注了不同群体规模下第三方惩罚的神经机制。本研究使用 EEG 分析从收益和损失的角度探讨了群体规模对第三方惩罚及其神经活动特征的影响。结果表明，在小群体规模和损失情境下，第三方的惩罚率和金额明显高于大群体规模和收益情境。EEG 结果表明，小群体中的第三方惩罚诱导出更大的 P2，而在大群体中，损失情境下的第三方惩罚诱导出更大的负性 LNP 和更多的θ波段激活。结果表明，第三方在小群体中寻求积极声誉的动机超过了其经济利益的平衡，倾向于惩罚违规者以维护公平规范。在这个过程中，损失情境起到了促进作用。然而，在大群体中，第三方对自身利益的考虑强于维持社会规范的意愿。本研究为群体环境中第三方惩罚以维持公平规范提供了神经科学证据，并从神经科学角度进一步解释了间接互惠理论。
