Ignoring a noisy metronome during dyadic drumming.

Introduction: This study investigated how the tonal and rhythmic properties of a "noisy metronome" and the opportunity for visual contact would affect drumming partners' abilities to synchronize with each other. Method: Participants' task was to drum a regular beat in synchrony with their partner at a prescribed tempo. They heard a metronome while drumming that they were instructed to ignore. We manipulated the noise profile of the metronome so that it contained long-range autocorrelations, short-range autocorrelations, or white noise. We also manipulated its pitch so that it formed a consonant or dissonant chord alongside the participants' drum tones. We assessed the effect of this noisy metronome on participants' synchronization stability, tempo, and body motion. Results: Our findings showed that the noisy metronome impaired synchronization between partners but improved tempo-keeping. Manipulations of the metronome's rhythmic and tonal properties had no effect on any of the outcome variables. The noisy metronome prompted increased head and hand motion from the participants (measured in terms of motion speed); head motion was also greater among active musicians than inactive/nonmusicians, and hand motion was greater among partners who knew each other. Visual contact improved synchronization and participants moved their drumming hand more when they could see each other than when they could not. Discussion: Our findings have implications for our understanding of how people process and respond to competing rhythms and the strategies they use to (co-)regulate the timing of their movements.