Evaluating the Dynamics of Unintended Interpersonal Coordination

TLDR

Interpersonal interactions involve tacit motor coordination, with prior work suggesting emergent synchrony arises from coupled oscillator dynamics. This study examines whether unintended between‑person coordination can be observed in a laboratory task to assess involvement of dynamical processes. Ten pairs performed a simple rhythmic task with visual feedback of each other's movements but no coordination goal. Cross‑spectral analysis revealed higher coherence and a phase‑angle distribution dominated by values near 0° and 180°, supporting the hypothesis that dynamical organizing principles underlie natural interpersonal synchrony.

Abstract

Past research has shown that interpersonal interactions are characterized by a tacit coordination of motor movements of the participants and has suggested that the emergent synchrony might be explained by a coupled oscillator dynamic. This study investigates whether unintended between-person coordination can be demonstrated in a laboratory task that will allow an evaluation of whether such dynamical processes are involved. Ten pairs of participants performed a simple rhythmic task in which they had visual information about each other's movements but had no goal to coordinate. A cross-spectral analysis of the movements revealed higher coherence and a distribution of relative phase angles that was dominated by values near 0 deg. and 180 deg. These results support the hypothesis that dynamical organizing principles are involved in natural interpersonal synchrony.