Gesture in hyperscanning during observation. Inter-brain connectivity

Non-verbal communication is a joint action defined by the use of different gestures’ types. The present research aimed to investigate the electrophysiological (EEG) correlates during the observation of affective, social and informative gestures in non-verbal communication between encoder and decoder. Moreover, the hyperscanning paradigm allows investigating the individuals’ inter-brain connectivity. Regarding gestures’ type, the study’s results showed a decrease of alpha (increased brain activity), and an increase of delta and theta brain responsiveness and inter-brain connectivity for affective and social gestures in frontal and posterior areas for informative ones. Concerning gestures’ valence, an increase of left frontal theta activity and inter-brain connectivity was observed. Finally, about the inter-agents’ role, the same brain responses and inter-brain connectivity patterns emerged both in encoder and decoder. This study allows discovering neural responses underlying gestures’ type and valence during action observation, highlighting the validity of hyperscanning to investigate inter-brain connectivity mechanisms.