Emotional Interactions in Human Decision Making using EEG Hyperscanning

We used the Ultimatum Game to investigate two person social decision making. The Ultimatum Game offers the experimental model to estimate the fairness, mind reading, conflict between emotion and cognition, and strategic behavior. We recorded simultaneous activity of the EEG from 64 scalp electrodes in 26 healthy participants (13 pairs of proposers and responders) and estimated the timefrequency analysis and nonlinear interdependence between the two players’ brain regions. We found that the face to face interactions modulate the Ultimatum Game behavior compared to the previous studies. We also found that the high frequency oscillations of frontocentral regions of the brain are closely related to the social interaction. Furthermore, information flow among frontocentral areas between the brains is stronger than that of other regions. This is the first study to analyze temporal dynamics and functional connectivity in human social decision-making using EEGs.