Beyond the metronome: auditory events and music may afford more than just interval durations as gait cues in Parkinson’s disease

Among the most apparent and adverse symptoms of Parkinson’s disease (PD) are disturbances
in gait. These include shuffling (small amplitude steps), instability (asymmetry and variability
between steps), freezing of gait (cessation of movement and difficulty with initiation), and general
disfluencies in walking movements and posture (Morris et al., 1996; Bloem et al., 2004; Grabli
et al., 2012). Limitations of pharmacological interventions to alleviate gait disturbances (Lord et al.,
2011), have led to interest in exploring non-pharmacological means of enhancing walking in PD, to
complement drugs-based approaches. Sensory cueing, in which perceptual guides for movement
are presented visually, acoustically, or haptically, is one such approach. While sensory cueing,
in particular rhythmic auditory cueing, is a viable and promising approach to enhancing gait in
PD, it is our opinion that this approach could be expanded by developing a more action-focussed
framework for understanding the information available to patients in sound (cues) and how this
information influences gait.