Follow you, Follow me: Continuous Mutual Prediction and Adaptation in Joint Tapping

TLDR

The study proposes that interpersonal coordination is facilitated by mutual prediction and millisecond‑scale adaptation. The authors used a joint finger‑tapping experiment where pairs synchronized to an auditory cue from either the other participant or a computer while maintaining a set beat. Dyads behaved as coupled hyper‑followers, showing no leader–follower strategy; they synchronized equally well with a responsive irregular partner or a predictable unresponsive computer, but performed worse when the partner was both irregular and unresponsive.

Abstract

To study the mechanisms of coordination that are fundamental to successful interactions we carried out a joint finger tapping experiment in which pairs of participants were asked to maintain a given beat while synchronizing to an auditory signal coming from the other person or the computer. When both were hearing each other, the pair became a coupled, mutually and continuously adaptive unit of two “hyper-followers”, with their intertap intervals (ITIs) oscillating in opposite directions on a tap-to-tap basis. There was thus no evidence for the emergence of a leader–follower strategy. We also found that dyads were equally good at synchronizing with the irregular, but responsive other as with the predictable, unresponsive computer. However, they performed worse when the “other” was both irregular and unresponsive. We thus propose that interpersonal coordination is facilitated by the mutual abilities to (a) predict the other's subsequent action and (b) adapt accordingly on a millisecond timescale.