Project 467206

Parkinsons Disease (PD) is the second most common neurodegenerative disorder and affects approximately 100,000 Canadians and 5 million adults worldwide. Hallmark motor deficits including resting tremor and gait disturbance are seen across disease stages, however non-motor impairments affecting visual and cognitive functions can appear decades before motor symptoms. Although PD patients are known to have impaired decision-making and greater impulsivity, the clinical tests used to assess and monitor these impairments are inadequate as they are greatly over-simplified and thus lack real-world applicability. Combined methods are required to link decision-making to other impairments in PD. I propose to use non-invasive eye movement measurements to investigate how PD patients process reward and risk information when making decisions, and how well they can inhibit unwanted actions. I will use a novel decision-making task using eye movements for choice selection. Two versions of the task will be used to measure saccades and smooth pursuit, two types of eye movements that are differentially affected in PD, allowing us to assess decision-making performance across different levels of oculomotor impairment. In addition, I will conduct an anti-saccade task to measure inhibitory control, a marker of impulsivity. Although medications exist to combat late-stage symptoms of PD, research must now shift to developing tools to better evaluate and monitor non-motor deficits which have a substantial negative impact on activities of daily living and patient quality of life overall. Eye-tracking offers an inexpensive, non-invasive method for assessing cognitive deficits which may accompany clinical exams to create a more comprehensive understanding of disease burden over time.