Social interaction enhances the pleasurable urge to move to music in people with Parkinson's disease

Background Music- and dance-based interventions can improve motor symptoms in people with Parkinson's disease (PD), but two key questions remain: whether the rhythmic complexity of music influences intervention outcomes, and whether social interaction further enhances these effects. Objectives To examine the effects of rhythmic complexity and interpersonal synchronization on subjective and objective movement responses to music in PD. Method Participants tapped to the beat of music with varying levels of rhythmic complexity across three cueing conditions: music alone, music with a visual beat cue, and socially with an assistant who also tapped to the beat. We measured pleasurable urge to move to music (PLUMM – or groove ), felt synchrony with the music, beat-related movement energy, and synchronization variability in 40 individuals with mild-to-moderate PD and 36 age-matched controls. Results Compared to music alone, social interaction increased PLUMM, felt synchrony, beat-related movement, and synchronization stability, with the strongest effects for moderate to high rhythmic complexity. These effects were stronger in participants with PD than in controls. In contrast, visual cues had no effect. Moreover, PLUMM ratings were positively associated with social closeness toward the assistant, trait empathy, and the experience of social reward through music. Conclusion Social interaction while moving to the beat of music enhanced both the urge to move and objective motor performance. Our findings show that improvements of motor symptoms through music- and dance-based interventions extend beyond enhanced temporal prediction through motor simulation; they also include socio-emotional mechanisms that promote pleasure and strengthen social bonding.