Control of Expressive and Metronomic Timing in Pianists.

In 12 tasks, each including 10 repetitions, 6 skilled pianists performed or responded to a musical excerpt. In the first 6 tasks, expressive timing was required; in the last 6 tasks, metronomic timing. The pianists first played the music on a digital piano (Tasks 1 and 7), then played it without auditory feedback (Tasks 2 and 8), then tapped on a response key in synchrony with one of their own performances (Tasks 3 and 9), with an imagined performance (Tasks 4 and 10), with a computer-generated performance (Tasks 5 and 11), and with a computer-generated sequence of clicks (Tasks 6 and 12). The results demonstrated that pianists are capable of generating the expressive timing pattern of their performance in the absence of auditory and kinaesthetic (piano keyboard) feedback. They can also synchronize their finger taps quite well with expressively timed music or clicks (while imagining the music), although they tend to underestimate long interonset intervals and to compensate on the following tap. Expressive timing is thus shown to be generated from an internal representation of the music. In metronomic performance, residual expressive timing effects were evident. Those did not depend on auditory feedback, but they were much reduced or absent when kinaesthetic feedback from the piano keyboard was eliminated. Thus, they seemed to arise from the pianist's physical interaction with the instrument. Systematic timing patterns related to expressive timing were also observed in synchronization with a metronomic computer performance and even in synchronization with metronomic clicks. These results shed light on intentional and unintentional, structurally governed processes of timing control in music performance.