Study Rationale:
Caloric vestibular stimulation activates the vestibular system, a sensory network with pathways spreading throughout the brain. The vestibular system is responsible for providing the brain with information about motion, head position and spatial orientation. Previous investigation has shown that eight weeks of twice-daily treatment using the proposed non-invasive caloric vestibular stimulation device in the home setting was associated with significant reductions in motor and non-motor symptoms in people with Parkinson’s disease. Study participants found treatments to be highly tolerable and the device easy to use. The device utilizes aluminum earpieces housed in a headset fashioned like headphones to activate the vestibular system. Device treatments have been shown to strongly regulate blood flow dynamics in the brain. Due to its widespread connectivity, the vestibular system is an ideal place to test non-invasive brain stimulation.
Hypothesis:
This study tests the hypothesis that time-varying caloric vestibular stimulation improves symptoms associated with Parkinson’s disease by modulating brain function.
Study Design:
Participants will be trained to use the device and will self-administer treatments (either active or placebo) at home twice daily for 12 weeks. Effects on brain functional connectivity and blood flow will be monitored using functional magnetic resonance imaging (fMRI) and symptoms will be assessed using standardized clinical scales. Effects of the treatment will be evaluated by comparing the change in scores from the pre-treatment baseline to the post-treatment assessment between the active and placebo treatment groups. Changes in brain function and symptoms will be compared to evaluate potential causal relationships.
Impact on Diagnosis/Treatment of Parkinson’s Disease:
These results will help guide modifications to the time-varying caloric vestibular stimulation device that may allow for greater reductions in Parkinson’s symptoms. This study will also add to the body of work required for insurance companies to cover a new therapy.
Next Steps for Development:
If successful, the outcomes will be used to guide future investigations, including 1) a study design to identify biomarkers during treatment that will enable individualized treatment protocols for maximal clinical efficacy, 2) a larger multi-center clinical trial to confirm the mechanism(s) of action for device treatment identified in this exploratory trial and 3) to guide a future pivotal trial investigating the safety and efficacy of treatment modifications stemming from this work.