Computation Method Of EEG Synchronization During Turn-Taking

Research on social neuroscience is increasing in recent years and many of them have used a new technique called "EEG hyperscanning",so it's of great importance to investigate the computation methods of EEG synchronization.This paper discusses all kinds of EEG synchronization measures,such as phase locking value,partial directed coherence,etc.And then summarizes the general process of EEG synchronization computation.In this paper,a two-person conversation experiment and a corresponding PDC-based computation method are designed to illustrate the functional connectivity between the two brains during turn-taking.Based on two kinds of corpus,the experiments were performed on 14 groups of volunteers.EEG signals and sound signals are simultaneously recorded,and then EEG signals were aligned with the sound signals to extract the EEG epochs during turn-taking.Considering the different roles of the two subjects during conversation,this paper establishes a double-variable auto-regressive model for each pair of the electrodes between the two subjects.PDC is selected as the synchronization measure and the synchronization between the electrodes is computed.Then the functional connectivity between the two brains is visualized on the delta,theta,alpha,beta and gamma bands.Based on FFT,the brain activation of the two brains is also visualized.Otherwise,this paper establishes a two-person brain network based on the functional connectivity of the two brains,analyses the in-degree and out-degree of the brain network and tries to recognize the turn-takings by the properties of the brain network.Our study show that:(1)functional connectivity of the two brains during turn-taking mainly concentrate between the middle temporal area,prefrontal area of the finish-talking person and the middle temporal area,inferior temporal area of the start-talking one;(2)the functional connectivity from the finish-talking person to the start-talking one is higher in the difficult corpus condition;(3)the brain network of the two brains during turn-taking can be separated from those of other times to some extent.