A point-process model of tapping along to difficult rhythms

Abstract

Experiments where participants synchronise their taps to rhythmic cues are often used to study human perception and performance of rhythms. This experimental study is novel in two regards: The cyclic rhythms (non-isochronous patterns of cues) presented to participants were more challenging than usual (including many from unfamiliar time signatures), and we have modelled participants’ performance via a conditional point process. Point processes are well suited to describing partly random sequences of events, but have rarely been used previously to model tapping experiments, the only other study we know being Cannon (2021). Our model uses continuous functional parameters to describe participants’ responses to auditory stimuli with much finer temporal resolution than in previous studies. Taking account of both the clock and the dynamic attention theories of sensorimotor synchronisation, we assessed the time course of the propensity to tap within each cycle at a resolution of less than 13$\mathrm{ms}$, identifying the influence of cues on the tapping propensity and the progress of learning their rhythmic patterns. We also sought to determine the trajectory of the putative refractory period (feedback inhibition of tapping) after each tap, and assessed the distribution of tap-cue asynchronies in a more finely resolved manner than usual. Our models also indicated complex kinetics of the feedback over about 100$\mathrm{ms}$.