Do we click: brain alignment as the neuronal basis of interpersonal communication
Communication naturally requires an interaction between at least two people. However, little is known about the underlying neuronal mechanism that facilitates the transfer of information between two brains during communication. In this study we utilize the inter-subject correlation (ISC) analysis to measure the brain alignment between speaker and listener brains during communication. The ISC analysis was used to directly compare the neuronal responses within the speaker’s brain during speech production with the neuronal responses within the listener’s brain during speech comprehension. The results indicate that during communication the brain of the speaker producing speech utterances becomes tightly coupled to the brain of the listener, and that such brain alignment facilitates successful communication. Specifically, we observed that (1) during conversation the brain responses of the listener are highly correlated with the brain responses of the speaker, (2) such brain alignment is mostly found in areas involved in both the production and comprehension of linguistic information, (3) as neuronal processing during communication unfolds over time, the time course of activity in the listener’s brain mirrors that of the speaker’s brain with temporal delays, and (4) the better the alignment between the speaker and listener brains, the better the communication.