Synchrony to a beat predicts synchrony with other minds

Abstract

Synchrony has been used to describe simple beat entrainment as well as correlated mental processes between people, leading some to question whether the term conflates distinct phenomena. Here we ask whether simple synchrony (beat entrainment) predicts more complex shared attentional states, consistent with a common mechanism. While eye-tracked, participants listened to regularly spaced tones and indicated changes in volume. Across multiple sessions, we found a reliable individual difference: some people entrained their attention more than others, as reflected in beat-matched pupil dilations that predicted performance. In a second study, eye-tracked participants completed the beat task and then listened to an eye-tracked storyteller. An individual’s tendency to entrain to a beat predicted how strongly their pupils synchronized with those of the storyteller, a measure of shared attention. The tendency to synchronize is a stable individual difference that predicts both beat entrainment and the coupling of minds, consistent with a common origin.

How and Why People Synchronize: An Integrated Perspective

“…Initial evidence for this hypothesis comes from studies finding greater synchrony for individuals higher in empathy (e.g., Coutinho et al, 2019) or lower in predisposition towards autistic-like traits (e.g., Cheng et al, 2017). Individuals who entrain to a beat more easily have been shown to engage in greater pupil synchrony with a storyteller, suggesting the capacity to synchronize may be a stable individual difference that transcends simple and complex tasks (Wohltjen et al, 2022). However, these individual effects are likely shaped by the context, personalities, and emotional capacities of one's interaction partners as well (Creavy et al, 2020).…”

“…1 We now know that partners synchronize across a wide variety of behaviors (facial movements, gestures, speech, walking tempo; e.g., Jackson et al, 2018;Zhao et al, 2022), physiological markers (pupil dilation, heart rate, heart rate variability, skin conductance; e.g., Kang & Wheatley, 2017;Wilson et al, 2018), and even neural states (Wheatley et al, 2012). The tendency to synchronize, at least physiologically, may be somewhat stable within individuals and across contexts (Wohltjen et al, 2022). Does interpersonal synchrony serve a function, or even multiple functions?…”