Part and whole perceptual-motor practice of a polyrhythm.

An experiment is reported that investigated the effectiveness of receiving the perceptual experience of a bimanual, 2:3 polyrhythm during motor practice of the unimanual parts of the polyrhythm. Thirty-six participants were randomly assigned to one of three practice groups: One group practiced both parts of the 2:3 polyrhythm coincident with both pacing metronome tones (whole practice). Another group practiced each rhythm separately, hearing only the pacing tone for the corresponding rhythm (part practice). A third group also practiced each rhythm separately but heard pacing tones for both rhythms during practice (part/whole practice). Each group performed 25, 40 s learning trials for each rhythm; 900 ms intervals for the left hand, and 600 ms intervals for the right hand (a 2:3 polyrhythm). Transfer tests consisted of continuation tapping of the component rhythms, both unimanually and bimanually. Polyrhythmic structure, but not absolute timing stability, was facilitated when training was conducted in the presence of the whole perceptual experience of the task, even when part of the task was practiced unimanually.