Moving in unison after perceptual interruption

Abstract

Humans interact in groups through various perception and action channels. The continuity of interaction despite a transient loss of perceptual contact often exists and contributes to goal achievement. Here, we study the dynamics of this continuity, in two experiments involving groups of participants ([Formula: see text]) synchronizing their movements in space and in time. We show that behavioural unison can be maintained after perceptual contact has been lost, for about 7s. Agent similarity and spatial configuration in the group modulated synchronization performance, differently so when perceptual interaction was present or when it was memorized. Modelling these data through a network of oscillators enabled us to clarify the double origin of this memory effect, of individual and social nature. These results shed new light into why humans continue to move in unison after perceptual interruption, and are consequential for a wide variety of applications at work, in art and in sport.

Figure 1

Four topologies during familiar human group cooperation situations, with various coupling modalities. (a) Complete graph: an ordinary organization during everyday working meetings; (b) Path graph: often present in sports, for instance in team rowing where partners are mechanically and visually coupled to two neighbors, except for the first and last rowers; (c) Ring graph: a common structure in many popular dances or among children at play (round dance); (d) Star graph: typical of musical ensembles, for instance when orchestra members are visually coupled only to the director. The image in panel (b) comes from unsplash.com, all the others from pixabay.com.

Figure 2

Main results of Experiment 1. (a) a representative example of phase synchronization r across periods of absence and presence of visual coupling (Time To Sync $\mathrm{TTS}=7.49\text{s}$ and Time In Sync $\mathrm{TIS}=9.78\text{s}$); (b) mean and standard deviation of phase synchronization across homogeneity (left panel) and topology conditions (right panel), $n=240$; (c) distribution of phase synchronization levels (High, Medium, Weak, Not in sync) for Similarity (left panel) and Topology (right panel), $n=60$.

Figure 3

Main results of Experiment 2. Mean and standard deviation of Phase synchronization r in Experiment 2 as a function of (a) Vision $\times$ Expertise, (b) Expertise $\times$ Topology, (c) Vision $\times$ Topology, $n=320$; (d) distribution of phase synchronization levels across categories of robustness for Expertise (left panel) and for Topologies (right panel), $n=80$.