Cortical correlates of gait in Parkinson's disease: impact of medication and cueing

Project Summary/Abstract Walking automaticity, the ability of the nervous system to successfully coordinate movement with minimal use of executive resources, is a critical functional skill for independent mobility in daily life, and may be improved by medication and/or appropriate rehabilitation-based intervention. This ability is compromised, even in early stages of Parkinson's disease (PD). PD is responsible for major mobility disabilities and cognitive dysfunction and a worse quality of life than most other chronic neurological diseases, and it imposes a heavy burden on the health care system. Aim I will investigate the relation between cognitive function and walking automaticity in subjects with PD and age-matched healthy control subjects by measuring brain activity in different parts of the cerebral cortex while walking and turning. Levodopa, the most common pharmacological treatment in PD, improves certain aspects of gait, but it may worsen or not change other aspects, such as balance. The effects of levodopa on gait automaticity are not well understood. Aim II will characterize the changes in cortical activity during walking due to usual levodopa intake in people with PD. Cueing is often being used in rehabilitation. More recently, due to the increasingly user-friendly wireless technology, personalized, closed-loop cueing devices are now being developed as an improvement over fixed cueing methods (such us walking to the pace of a metronome or stepping over lines placed on the floor). Recently, we showed that step-synchronized tactile feedback improved gait automaticity in PD; however, it is not known which brain mechanisms are associated with learning of this tactile-feedback technique, nor if benefits transfer to mobility during daily-living. Our objective is to investigate the effects of step-synchronized, tactile cueing on gait automaticity measured in the laboratory; this is Aim III, a clinical trial. In addition, Aim III will explore the feasibility of using the cueing system at home for one week. This project will characterize the cortical correlates of gait automaticity, the changes in gait automaticity with dopamine replacement and cueing in people with PD, and how these changes translate to improvement in gait and turning. In with survivors. ultimately addition, personalized cueing-based rehabilitation could be effective for many other populations gait disturbances, such as peripheral neuropathy, multiple sclerosis, traumatic brain injury, and cancer There are minima l risks associated with this technology and the benefits could be significant in improving walking and reducing falls in various populations.Furthermore, by understanding more about the brain mechanisms associated with walking automaticity and motor learning through cueing, we will be able to open a new route for innovative, more tailored, rehabilitation interventions.