How to hit that beat: Testing acoustic anchors of rhythmic movement with speech

Sensorimotor synchronisation with metronome and music have been extensively studied, while synchronisation with speech is still relatively poorly understood. The present study looks into the question how to define the best anchor of synchronised movement (finger tapping) in speech, and compares manually identified vowel onsets with four acoustic landmarks that were derived by different signal processing algorithms. Participants listened to repetitions of natural English sentences and were instructed to tap in synchrony with what they perceived to be the sentence beat. The time course of the sentences was tagged for a number of rhythmically relevant events, including vowel onsets, fastest energy increase (maxD), a combination of high local pitch and periodic energy (PPP), and the largest amplitude of intersyllabic and interstress timescales (IMF1 and IMF2). Vowel onsets and maxD showed consistent tapping patterns, while other landmarks performed worse than vowel onsets. These findings suggest that local energy changes shape sensorimotor synchronisation with speech and that energy contours might serve as anchors of rhythmic attention in spoken language.