Brain Hygge in September: Merle Fairhurst

Abstract:

Interpersonal coordination requires individuals to continuously balance representations of the self with representations of others. In temporal coordination tasks such as group music making and sports, coordination typically occurs without sustained interpersonal touch. Dance is different: touch may be continuous or introduced at critical moments that can transform the quality of the interaction. What, then, does touch add to interpersonal coordination?

Our previous work has identified partially distinct neural networks supporting coordination with another person versus taking the lead. More recently, we have shown that successful coordination and self-agency depend on dynamically balancing self-oriented representations with representations of the self in relation to others. We have therefore proposed that effective interpersonal coordination depends not on maximal synchrony, but on a dynamic balance between self and self–other representations.

In this talk, I introduce a social virtual reality paradigm in which participants experience touch without touching through pseudohaptic stimulation. This allows us to manipulate the social experience of touch while minimizing peripheral tactile input. We hypothesize that interpersonal touch transforms the coupling architecture of the interaction—enhancing the precision of the partner model, establishing a reciprocal sensorimotor loop, and dynamically reweighting self- and other-related representations.

We predict that socially meaningful touch will engage the right temporoparietal junction (rTPJ), reflecting the representation of the bodily and social relationship between self and other. Using geometrical approaches to interbrain dynamics, we further test whether touch reorganizes the directionality and geometry of interpersonal neural trajectories, linking these changes to movement and autonomic dynamics.

Thus, touch may provide more than an additional sensory channel. It may reconfigure the communication loop between interacting brains, enabling individuals to coordinate more precisely while simultaneously sharpening the representation of the relationship between self and other.