Responders to Rhythmic Auditory Stimulation in Individuals Post-Stroke and Older Adults

Stroke is among the leading causes of long-term disability worldwide. Post-stroke neuromotor impairments are heterogeneous, yet often result in reduced walking ability characterized by slow, asymmetric, and unstable gait patterns. Rhythmic Auditory Stimulation (RAS) is an emerging rehabilitation approach that leverages auditory-motor synchronization to retrain neuromotor control of walking. Indeed, walking with RAS can enhance walking rhythmicity, gait quality, and speed. RAS is a potentially valuable tool for walking rehabilitation after stroke; however, despite extensive research evidence on the overall benefits of RAS in people with chronic stroke, the notable variability in the walking characteristics of individual patients is likely to influence the effectiveness of RAS intervention, and thus requires study. Furthermore, beyond stroke-related factors, age-related changes may also affect how well individuals post-stroke respond to RAS. This study aims to recruit 24 individuals post-stroke and 20 older adults to evaluate the effects of stroke- and age-related neuromotor impairment on RAS intervention. Each study participant will complete two six-minute walk tests: one without RAS (baseline) and the other with RAS delivered using a metronome. The investigators hypothesize that post-stroke individuals will, on average, exhibit a positive response to RAS intervention (i.e., walk farther and with greater gait automaticity (i.e., reduced stride time variability), with the degree of response predicted by specific baseline characteristics. Furthermore, the investigators anticipate that these walking enhancements will be accompanied by improvements in gait biomechanics and a reduction in the metabolic cost of walking. The investigators hypothesize that older adults will exhibit similar, but attenuated, effects of RAS.

Inclusion Criteria: * Be able to communicate with investigators clearly * The ability to walk without another individual supporting the person's body weight for at least 6 minutes. Assistive devices, such as a cane, are allowed. Exclusion Criteria: * Inability to communicate (as assessed by a licensed physical therapist) * Pain that impairs walking ability (as assessed by a licensed physical therapist) * Unexplained dizziness in the last 6 months (self-report) * Severe comorbidities that affect walking or may interfere with the ability to participate in the study (musculoskeletal, cardiovascular, pulmonary, and neurological) * More than 2 falls in the previous month Stroke-specific Inclusion Criteria: * at least 6 months post-stroke Older adults specific Inclusion Criteria: * 65 to 80 years of age