Investigating face processing in online interactions via UK-US Hyperscanning using fNIRS.

Videoconferencing technology has become a staple of everyday life and has found widespread use in business, education, and telemedicine. Despite this, there have been few empirical studies investigating the neural correlates of interactions during this form of communication. This study investigates the neural mechanisms of face processing during online video-conferencing, employing functional near-infrared spectroscopy (fNIRS). We synchronised presentation and acquisition of fNIRS data across labs in the UK and US using custom Python software and a third-party computer system. Using this framework, we examine how different presentations of faces (live-online vs. static images) influence social cognition and inter-brain coupling (IBC) in a videoconferencing context. Forty participants (20 dyads) engaged in online sessions where they viewed either dynamic video feeds or static images of their partners' faces. In line with our hypotheses, our findings did not show preferential activity in the right supramarginal gyrus during the observation of live online faces compared to static faces, whilst marginally higher IBC was found between the angular gyri during the observation of live faces compared to static. Findings suggest that on-line studies of social interaction provide a relevant field of investigation.