Cognitive Change clinical trials at University of California Health

The goal of clinical trial is to learn about how blood pressure fluctuations affect cognitive performance (thinking abilities) and brain blood flow in persons with Parkinson's disease with and without orthostatic hypotension (low blood pressure when standing). The main questions it aims to answer are: - Is there a certain level of blood pressure that correlates with change in cognitive performance while upright? - Is there a certain level of change in brain blood flow that correlates with change in cognitive performance when upright? - How does cognitive performance differ between persons with Parkinson's disease that have orthostatic hypotension and those without orthostatic hypotension? - How does cognitive performance differ between the supine (laying down) and upright positions? - How do blood pressure and brain blood predict changes in cognitive performance over two years? Participants in this study will undergo the following procedures: - Complete a screening visit with questionnaires, medical history, physical exam, and head-up tilt-table test. - Attend one baseline study visit, during which they will undergo a battery of computerized cognitive tests repeated twice: once while laying down and once while upright on a tilt table. Simultaneously, during the experiments we will measure blood pressure using a wrist-worn device and inflatable arm cuff and will measure brain blood flow using functional near-infrared spectroscopy (fNIRS), a non-invasive device that uses light sensors to detect changes in brain blood flow. - Attend one two-year follow-up visit, during which they will repeat a battery of computerized cognitive tests repeated twice: once while laying down and once while upright on a tilt table. During this visit, like before, we will measure blood pressure using a wrist-worn device and inflatable arm cuff and will measure brain blood flow using functional near-infrared spectroscopy (fNIRS). Researchers will compare participants with Parkinson's disease with and without orthostatic hypotension in the laying down and upright positions to see if there are changes in thinking abilities between these groups.