Identifying the Neural Signature of Exercise to Advance Treatment of PD Cognitive Declines

Parkinson's disease (PD) is a progressive neurological disease, most prevalent in older adults, estimated to affect over 12 million people world-wide by 2040. Traditionally considered a motor disorder, the impact of PD on cognitive performance is now widely accepted with 80% of PD patients developing executive function impairments. Typical PD related cognitive effects include impaired information processing, set-switching, working memory and dual-tasking. While antiparkinsonian medication and deep brain simulation (DBS) are effective in managing disease symptoms, disease modification has remained elusive. Exercise has been proposed as the Universal Prescription for PD capable of slowing disease progression; stationary cycling in particular has been suggested as an ideal exercise modality for people with PD (PwPD). The investigator's seminal tandem cycling study was the first to utilize forced exercise (FE) in human PD patients and demonstrated a 30% improvement in clinical ratings compared to voluntary exercise (VE). Briefly, FE is a mode of high intensity exercise originating in animal models of PD in which voluntary exercise rate is augmented, but not replaced. Thus, PwPD were assisted in pedaling at a higher rate (cadence) on the tandem cycle compared to those on a standard stationary cycle performing voluntary exercise (VE). This work resulted in a paradigm shift in terms of recommending high intensity exercise for PwPD. Despite the potential of exercise to alter disease progression, its mechanism of action and effects on basal ganglia function are not understood.