Hyperconnectivity by Simultaneous EEG Recordings during Turn-taking

Abstract

Turn-taking is a common scene in our daily life, however, the neural mechanism behind it is not fully understood yet. Researchers have proposed several theories to explain this phenomenon, and one of these theories is the oscillator model. In this model, the brains of the speaker and the listener are described as two "oscillators" and become mutually entrained during turn-taking. EEG hyperscanning is a method for studying two or more individuals simultaneously with the objective of elucidating how co-variations in their neural activity are influenced by their behavioral and social interactions. Turn-taking, as a frequent social interaction, could be investigated with EEG hyperscanning technique. In this paper, we designed an experiment allowing us to simultaneously record the EEG signals of the subjects during turn-taking in conversations, and depicted the method to measure the "hyperconnectivity" (functional connectivity between the two brains) by means of Partial Directed Coherence. Our study showed that: (1) there are significant hyperconnectivity links between the speaker and the listener; (2) The hyperconnectivity links mostly direct from the speaker to the listener; (3) Hyperconnectivity links in Beta band are much denser than those in Alpha band; (4) The T8 electrode plays a key role in the hyperconnectivity network.