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Directed causal networks for leading and following in hyperscanning EEG
Lykke Silfwerbrand1,2, Yasuharu Koike2, Malin Gingnell1,3
1Department of Medical sciences/Psychiatry, Uppsala Universitet Disciplinary Domain of Medicine and Pharmacy, Uppsala, Sweden.
Abstract:
This explorative hyperscanning EEG whole-brain study describes activation networks within and between brains representing leading and following behavior. The directed information flow was analyzed for singles and pairs of brains simultaneously activated using the graph-based algorithm of PCMCI. This algorithm was previously tested for frontal activations in singles and pairs of brains, returning significant directed statistical dependencies. The participants led and followed each other using a minimal model based on rhythmic tapping. This whole-brain study resulted in directed causal connections representing neuronal networks for the social activities studied. The brain regions exhibiting the highest number of connections were chosen for further analysis from the extensive network of connections. This resulted in four networks representing within-brain and between-brains, respectively, for leading and following. Network commonalities aligned with previous research of leading and following reflecting cognition, working memory and social cognition, visual attention, and motoric engagement. Follower networks exhibited socially adaptive activations. The between-brain networks appear to involve more brain regions, possibly reflecting the more complex situation involving another person. The PCMCI could prove to be a suitable tool for identifying whole-brain networks of directed causality that represent leading and following, both within and between brains, using hyperscanning EEG data.

