Tackling Some Key Methodological Challenges in EEG Hyperscanning Research

• In Event: Innovations in the Developmental Study of Biobehavioral Synchrony

Abstract

We know very little about the human brain mechanisms that support dynamic social interactions in ecologically valid environments. This is in part due to the limitations of current cognitive neuroscience methods, which often call for participants to perform individual tasks in highly constrained and unnaturalistic settings. A growing body of research has begun to compare the neural activity across individuals, often using a so-called hyperscanning approach: recording brain activity from multiple people simultaneously during a social task. This work has generated important insights into the potential of inter-brain synchrony as a biomarker for a number of cognitive processes and behavioral outcomes, including, among others, memory retention, task engagement, attentional direction, pain reduction, empathy, social closeness, and personal preference.
However, many challenges remain. We illustrate a subset of these challenges with a series of ongoing EEG hyperscanning projects from our research group. Specifically, we address how our work aims to (a) disentangle stimulus-induced inter-brain synchrony from inter-brain synchrony resulting from socially relevant engagement; (b) elucidate the relationship between individual and ‘shared’ brain activity in learning and social communication between children and adults; (c) tackle practical challenges related to EEG hyperscanning in groups and young children; and (d) assess the cognitive and behavioral significance of different metrics that are used to quantify ‘synchrony’.
For example, in one study currently underway, students view emotional videos either alone or together with the goal to address to what extent the neurobiological markers of social behavior can be reliably probed by inter-brain synchrony above and beyond mere audio-visual entrainment to the video stimulus. In other work, we find that inter-brain synchrony but not intra-brain synchrony in the alpha-band (8-12Hz) predicts learning, raising questions around the significance of inter-brain synchrony as a methodological approach as opposed to (or in addition to) constituting a neural marker of social engagement. Also aimed at disentangling the difference between inter- and intra-brain markers are studies comparing adult-child interactions involving either children with autism spectrum disorder or typically developing children, and studies comparing families from low vs. high socio-economic backgrounds. We further discuss research investigating if caregiver-child inter-brain synchrony supports dyadic joint engagement and language acquisition, to illustrate practical challenges associated with hyperscanning in children. Finally, to support and promote the standardization of inter-brain synchrony analysis approaches (a “gold standard” if you will), we recently developed HyHyP, an open-source python-based comprehensive and easy open-source software package that allows (social) neuroscientists to carry out and to interpret inter-brain connectivity analyses.

Authors

• Emma Laurent, Harvard University
  Presenting Author

• Phoebe Chen, New York University
  Non-Presenting Author

• Suzanne Dikker, New York University, USA
  Non-Presenting Author