Endogenous Rhythms Constrain Musicians’ and Nonmusicians’ Timing in Joint Performance

The ability to precisely time one’s motor output to that of others is critical to behaviours involving interpersonal coordination such as music performance, speech or dance. Previous studies have shown that endogenous rhythms (spontaneous rates) influence interpersonal synchrony between musicians performing a joint musical task. Our primary goal was to investigate the combined influence of spontaneous production rates and musical training on the size and direction of asynchronies in a music production task. We first recorded the spontaneous motor tempo (natural finger-tapping rate, without auditory feedback) and spontaneous production rate (natural music performance rate, with melodic auditory feedback) of musician and non-musician participants using a force-sensitive pad. Participants then tapped the same melody in synchrony with a partner following a metronome cue, set to each partner’s solo spontaneous production rate. We observed large consistent individual differences in spontaneous tapping rates, and identified spontaneous motor tempo and spontaneous production rate as distinct measures of endogenous rhythms. We reported evidence that spontaneous production rates predict interpersonal synchrony in joint music performance, and more so for non-musicians. In addition, I will present a non-linear analysis of complex dynamical systems, Recurrence Quantification Analysis (RQA) and discuss its application to inter-tap intervals and synchronization data, in order to better define the dynamical differences between musicians and non-musicians. Our findings suggest that the same endogenous rhythmic principles constrain tapping performance in musically trained and untrained individuals, although they place greater constraints on non-musicians’ timing. These findings are consistent with non-linear dynamics predictions of coupled oscillators and offer potential for understanding temporal dynamics in other social tasks such dance, team sports, or conversational speech.