Tapping into Rhythm: How Polyphonic Drum Patterns Map to Monophonic Contours and Support Pattern Retrieval

This study investigates how listeners reduce polyphonic drum patterns into simplified monophonic rhythm contours through tapping behavior. We examine how these contours relate to metrical structure, onset density, syncopation, and frequency-weighted onset density (FWOD), and whether these features can support rhythm retrieval tasks. Across three experiments, participants tapped rhythmic contours using a force-sensitive interface while listening to polyphonic drum patterns. The results show that tap force is shaped primarily by metrical structure, while FWOD captures an additional bottom-up component related to timbral and density-based salience. Among the analytical contour representations tested, FWOD also provided the best performance in rhythm retrieval tasks within a two-dimensional rhythm-space embedding. Together, these findings suggest that listeners simplify polyphonic rhythmic information through a combination of metrical expectations and spectrally weighted onset density. The study further supports FWOD as a compact and behaviorally relevant representation for rhythm analysis, retrieval, and interactive music systems, with potential applications in rhythm-based interaction, music production workflows, and generative musical interfaces.