Tapping to Ragtime: Cues to Pulse Finding

Abstract

Two experiments investigated cues to pulse finding using a relatively unconstrained, naturalistic paradigm. Participants tapped what they felt was a comfortable pulse on a keyboard playing a percussive sound. The stimulus materials were based on ragtime excerpts, played metronomically (i.e., without expressive timing or tempo variation). The first experiment, with 8 musically experienced and 8 musically inexperienced subjects, played each excerpt in two versions: a pitch-varied version (the original excerpt) and a monotonic version (with all tones changed to middle C) that was designed to remove all melodic and harmonic cues to pulse. Neither the absence of pitch information nor musical experience significantly affected performance. The second experiment tested 12 musically experienced subjects on shorter excerpts from the same ragtime pieces. Full (right-hand and left-hand parts together) and right-hand-only versions of the excerpts were each played in pitch-varied and monotonic versions. Removing the left-hand part significantly affected tapping performance on a number of measures, causing a lower percentage of tapping on the downbeat, more off-beat taps, more aperiodic taps, more switches between tapping modes, a higher variability of the intertap interval, and larger deviations from the beat. As a whole, these indicate a negative effect of removing the left-hand part. Again, differences between pitch-varied and monotonic versions were generally small. Analysis of the music revealed the following cues to pulse finding: a predictable alternating bass pattern in the left-hand part and a majority of notes on metrically strong positions in both the right-hand and left-hand parts. These results suggest that, for piano ragtime music, temporal cues are prominently available for finding and following the pulse and that pulse finding is largely independent of pitch information. Implications of the experimental measures and music-analytic techniques for models of pulse perception are considered.