An Oscillator Model for Interbrain Synchrony: Slow Interactional Rhythms Entrain Fast Neural Activity

Synchronization is a self-organizing process spanning multiple levels of organization. With advances in brain imaging and hyperscanning technologies, the pervasiveness of interbrain neural synchrony in widely different experimental settings is slowly attracting attention in the field. Despite its prevalence, the underlying mechanisms for interbrain neural synchrony remains largely unexplained, with recent interpretations attempting to approach the problem from the theory of mind, mentalization and shared intentionality perspective. One highlighted issue regarding the difficulty in providing a sound explanation is that neural activities are occurring at orders-of-magnitude faster timescales than the social interaction itself. Using two minimal evolutionary models based on Kuramoto coupled oscillators, we provide an alternative perspective as to how interbrain neural synchronization might occur. Borrowing concepts from recent hypotheses, we argue that 1) embodied engagements form a new autonomous “interaction” system, which 2) through its slower dynamics exert constraints on the faster neural dynamics within the heads. If this is true, the key to understanding interbrain neural synchrony could be through understanding the nature of the interaction itself.