Investigating EEG inter-brain synchrony: methods to gather meaningful evidence
Year: 2024
Type: preprint
Abstract: Synchrony has been proposed as a relevant phenomenon for investigating social neurophysiological and psychological processes, with inter-brain synchrony, in particular, presumed to facilitate the functional integration of multiple brains. However, the lack of an accepted definition and a cohesive theoretical corpus that allows hypothesis-based approaches, often combined with inadequate empirical methods, weakens this area of research. To address this, we propose a rigorous definition of inter-brain synchrony and link various theoretical contributions to justify the existence of meaningful temporal alignment between different brain activities. This article outlines a set of methods to provide valid evidence supporting this neural mechanism. Our approach entails extracting instantaneous phase data from Hilbert-transformed EEG time series recorded from individuals under different experimental conditions that account for confounding factors such as shared attention, cognitive, and motor dependencies. We then describe multiple data analysis approaches, including circular statistics combined with permutation testing, and mutual information. Finally, we present an example of a potential application within the context of cooperation in nuclear families. We believe that, by employing such methods consistently, the concept of inter brain synchrony is falsifiable. Whether this phenomenon is empirically supported or not, it will contribute to advancing our understanding of the social brain.
Institution: Ghent University
Language: English
Subfield: Social Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W4404525969