The ways our hearts tick together – A vegetative hyperscanning study involving a self-paced interpersonal motor entrainment task

Abstract

Cardiac physiological synchrony between two persons is considered to be an important component of social interaction. Yet, the processes underlying physiological synchrony remain unclear. We aim to investigate these processes. 20 dyads (19 men, 21 women, age: mean 23.7, range: 18–35) engaged in a self-paced interpersonal tapping synchronization task under different conditions of blocking sensory communication channels. Applying wavelet transform coherence analysis, a significant increase in heart rate synchronization from baseline to task execution was found while there was no statistically significant difference across conditions. Furthermore, the control analysis, which assessed the synchrony between randomly combined dyads of participants showed no difference from the original dyads’ synchrony. We showed that interindividual cardiac physiological synchrony during self-paced synchronized finger tapping resulted from a task-related stimulus equally shared by all individuals. We hypothesize that by applying mental effort to the task, individuals changed into a similar mental state, altering their cardiac regulation. This so-called psychophysiological mode provoked more uniform, less variable oscillation patterns across all individuals leading to similar heart rate coherence independent of subsequent pairings. With this study, we provide new insights into heart rate coherence and highlight the importance of appropriate study design and control analysis.