Standstill to the 'beat' - differences in involuntary movement responses to simple and complex rhythms.

Previous studies have shown that movement-inducing properties of music largely depend on the rhythmic complexity of the stimuli. However, little is known about how simple isochronous beat patterns differ from more complex rhythmic structures in their effect on body movement. In this paper we study spontaneous movement of 98 participants instructed to stand as still as possible for 7 minutes while listening to silence and randomised sound excerpts: isochronous drumbeats and complex drum patterns, each at three different tempi (90, 120, 140 BPM). The participants' head movement was recorded with an optical motion capture system. We found that on average participants moved more during the sound stimuli than in silence, which confirms the results from our previous studies. Moreover, the stimulus with complex drum patterns elicited more movement when compared to the isochronous drum beats. Across different tempi, the participants moved most at 120 BPM for the average of both types of stimuli. For the isochronous drumbeats, however, their movement was highest at 140 BPM. These results can contribute to our understanding of the interplay between rhythmic complexity, tempo and music-induced movement.