What binds us? Inter-brain neural synchronization and its implications for theories of human consciousness.

Tom Froese,Ana Lucía Valencia

doi:10.1093/nc/niaa010

Abstract

The association between neural oscillations and functional integration is widely recognized in the study of human cognition. Large-scale synchronization of neural activity has also been proposed as the neural basis of consciousness. Intriguingly, a growing number of studies in social cognitive neuroscience reveal that phase synchronization similarly appears across brains during meaningful social interaction. Moreover, this inter-brain synchronization has been associated with subjective reports of social connectedness, engagement, and cooperativeness, as well as experiences of social cohesion and ‘self-other merging’. These findings challenge the standard view of human consciousness as essentially first-person singular and private. We therefore revisit the recent controversy over the possibility of extended consciousness and argue that evidence of inter-brain synchronization in the fastest frequency bands overcomes the hitherto most convincing sceptical position. If this proposal is on the right track, our understanding of human consciousness would be profoundly transformed, and we propose a method to test this proposal experimentally.

Highlights

In social cognitive neuroscience, a shift toward embodied, enactive, and participatory approaches has started to take place, moving away from individual brains and focusing on a person’s interaction with the environment
If this proposal is on the right track, our understanding of human consciousness would be profoundly transformed, and we propose a method to test this proposal experimentally
Keeping in mind that intra-brain neural oscillations are known to play a critical role in cognitive processes and, more importantly, that largescale phase synchronization has further been proposed as the neural basis of consciousness (Crick and Koch 1990; Thompson and Varela 2001; Ward 2003; Engel et al 2016), reports of modifications on the ongoing oscillatory activity of several individuals due to social interaction have important implications for our study of human behaviour

Summary

Introduction

A shift toward embodied, enactive, and participatory approaches has started to take place, moving away from individual brains and focusing on a person’s interaction with the environment. Keeping in mind that intra-brain neural oscillations are known to play a critical role in cognitive processes (since they represent the precise timing of neural activity Buzsaki 2006; Sauseng and Klimesch 2008) and, more importantly, that largescale phase synchronization has further been proposed as the neural basis of consciousness (Crick and Koch 1990; Thompson and Varela 2001; Ward 2003; Engel et al 2016) (see below), reports of modifications on the ongoing oscillatory activity of several individuals due to social interaction (as measured using EEG-based hyperscanning) have important implications for our study of human behaviour.

Results

Conclusion