Percept Transitions in FOG and PD

The purpose of this research is to examine the underlying pathophysiology and biomarkers of freezing of gait (FOG) and cueing-evoked improvements. This protocol will use the novel (on-label, FDA-approved) local field potential (LFP)-measuring capability of the Medtronic Percept™ deep brain stimulation (DBS) system to compare oscillatory activity in people who have Parkinson's disease (PD), with and without freezing of gait (FOG). This will be conducted as three separate experiments, participants may volunteer for one or more experiments: Experiment 1: The first experiment will compare LFPs during gait initiation with and without a cue, in people with (PD+FOG) and without FOG (PD-FOG). Experiment 2: In the second experiment, the investigators will compare LFPs during the successful movement transitions vs. freezing-events during a FOG provocation course in people with FOG. Experiment 3: In the third experiment, the investigators will compare LFPs during rapid alternating movements of the wrist and/or foot, in people with and without FOG.