Detecting social interaction during the Prisoner's Dilemma Game using EEG hyperscanning

Abstract

Social interaction is an important feature in human relationship. It is achieved not only through verbal communication but also through non-verbal communication, such as eye-contact. Because decision-making most often occurs in social contexts, one can say that decision-making reflects the social aspect of human beings. Humans usually tend to make decision that serves their own interests. However, the natural human concern for others’ well-being leads to cooperative behavior rather than competitive behavior. The human in-clination for cooperative behavior suggests that social interaction highly affects the conse-quence of economic decision-making. In this thesis, we used an EEG hyperscanning to in-vestigate varying neural mechanisms of economic decision-making depending on the dif-ferent levels of social interaction during participation in the iterated Prisoner’s Dilemma Game (PDG). 64 male subjects participated in this study. We modulated the level of social interaction by dividing participants into two groups: participants from one group played the game face-to-face and those from the other group played the game blocked, without facing each other. EEGs were recorded from 40 subjects, 20 subjects from each group respective-ly. EEGs were simultaneously recorded using dual EEG systems. Behavioral results showed that mutual cooperation between players was more frequent in the face-to-face PDG. Our time-frequency analysis and source localization results suggested that the superi-or parietal lobule (SPL) plays a key role in social interaction together with the cuneus (CUN) and the precuneus (PC) during the face-to-face communication. Moreover, the acti-vation of the SPL may lead players to cooperate in the context of the PDG. Intra-brain and inter-brain analyses further revealed the significant neural synchronization across the frontal lobe, the temporal lobe, and the parietal lobe within the brain and between brains during face-to-face communication; the neural s...