Thesis Format

Integrated Article

Optimizing Gait Outcomes in Parkinson’s Disease Using Rhythmic Auditory Stimulation: The Effects of Groove & Beat Salience

Author

Kristi M. Von Handorf, The University of Western OntarioFollow

Degree

Doctor of Philosophy

Program

Psychology

Supervisor

Grahn, Jessica A.

Abstract

Rhythmic auditory stimulation (RAS) is an intervention for gait-disordered populations that involves synchronizing footsteps to regular auditory cues. Previous research has shown that high-groove music (music that induces the desire to move or dance) improves gait relative to low-groove music, but it is unclear why. One possibility is that the greater beat salience inherent in high-groove music may improve gait because salient beats are easier to synchronize with. To test this, we manipulated beat salience by embedding metronome tones to emphasize beat onsets in both high- and low-groove music. We expected that, if beat salience drives gait improvements to high-groove music, then embedding metronome in low-groove music would elicit similar gait improvements (e.g. increased stride velocity). We quantified gait synchronization in terms of period matching (step rate to the cue pace) and phase matching (individual step onsets to beat onsets). The studies in this thesis assess healthy younger and older adults and people with Parkinson’s disease (PwP), walking to auditory cues matched to 10% faster than baseline cadence. We found that high beat salience is an important contributor to the effects of groove on gait, especially when the embedded metronome is a low-pitch bass drum. However, beat salience does not fully explain gait changes, nor does it enhance synchronization: groove improves accuracy, but beat salience does not. Thus, other musical features present in high-groove music may drive additional gait parameter changes. We also manipulated whether participants synchronized or walked freely. Instructions to synchronize improved gait speed in all populations, but also increased variability. However, in PwP, free-walking to music (especially with an embedded metronome) increased gait speed and decreased or maintained variability. This supports previous research in which embedding a metronome emphasizes rhythmic structure and reduces the cognitive demand associated with perceiving and synchronizing with the beat. Finally, we found that good beat-producers were more likely to improve gait to RAS cues than poor beat-producers, but that effects of beat production ability were generally small and do not fully explain individual variability in RAS responses.

Summary for Lay Audience

This thesis explores a therapy for people with Parkinson’s disease (PwP) called Rhythmic Auditory Stimulation (RAS) which improves gait (walking). RAS involves people trying to synchronize their footsteps to regular cues, like music. Though this therapy is helpful for some individuals, it doesn’t work for everyone. Knowing more about what factors influence the response (such as musical features) may help us optimize RAS by tailoring treatment to the individual.

Walking to music that is groovy, or fun to dance to, improves gait in PwP. However, it’s unclear what musical features lead to this improvement. One possibility is that groovy music simply has a clear beat, and research shows that simple metronome cues (i.e. regular beeps without music) often improve gait in PwP. Thus, the clear beat in groovy music may cause gait improvements. To test this, we added a metronome to music that is not groovy and tested whether PwP improved as much compared to music that is groovy. We found that adding a metronome to less groovy music does improve gait, but not as much as groovy music itself. This suggests that a clear beat is important for gait improvement, but so are other musical features found in groovy music. Furthermore, we found that a metronome with a lower-pitched sound (a bass drum) helps people walk faster and more accurately than higher-pitched sounds.

Factors unrelated to the music can also influence how PwP respond to RAS. Two of these factors include the ability to synchronize movements to music and whether people are instructed to synchronize or not. People who had better ability to tap in synchrony with music were more likely to improve gait. For people who have worse ability to synchronize, gait sometimes worsens, because paying extra attention to the music may be distracting. However, when the beat is clear, less attention is needed. Thus, not explicitly instructing participants to synchronize may be ideal when a metronome is added. Together, these findings are important because we can potentially add a metronome to music to improve gait, allowing PwP to listen to their own favourite music during RAS.

Recommended Citation

Von Handorf, Kristi M., "Optimizing Gait Outcomes in Parkinson’s Disease Using Rhythmic Auditory Stimulation: The Effects of Groove & Beat Salience" (2025). Electronic Thesis and Dissertation Repository. 10817.
https://ir.lib.uwo.ca/etd/10817

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