Neural mechanisms of social coordination: Continuous EEG analysis using a novel 4d colorimetric method

E. Tognoli, D. Benites, G. C. De Guzman, J. A. S. Kelso


Dynamical systems are often characterized by states (during which a behavior is sustained) and state transitions leading from one behavioral regime to another. The latter are information-rich but until now, tools to analyze their associated neural dynamics were lacking. To understand the brain mechanisms of behavioral coordination between people, we focused on the transition from uncoordinated to coordinated social behavior. We developed a 4D colorimetric method to analyze EEG spatio-temporal patterns associated with these behavioral transitions. We applied this technique to the continuous EEG of two people engaged in intentional social coordination. Subjects performed rhythmic right index finger movements in full view of each other under instructions to establish one of three collective behaviors: inphase (both fingers flex/extend in synchrony), antiphase (one subject extends while the other flexes) and intrinsic (both subject maintain their own movement and do not intend to synchronize). Transitions to coordinated behavior were identified and classified according to agency, i.e., who effects the transition, task goal, and behavioral strategy. For both partners, we identified brain patterns that were: (1) specific to a class of coordinated behavior, and (2) observed irrespective of the mode of coordination. The potential of this new method to understand the brain mechanisms of joint action will be discussed. [PPT].