This protocol will characterize the effects of deep brain stimulation (DBS) location (both adverse and beneficial) on motor signs in people with Parkinson's disease (PD). This information can be used to inform future DBS protocols to tailor stimulation to the specific needs of a patient. If targeted dorsal GP stimulation is shown to significantly improve motor features that are typically resistant to dopamine replacement therapy, these experiments will likely have major impact on clinical practice by providing a potential strategy to these medically intractable symptoms.

Inclusion Criteria:

• diagnosis of idiopathic PD
• have undergone neurosurgery to implant deep brain stimulators in the globus pallidus (GP DBS) or subthalamic nucleus (STN)
• Existing 7T brain imagery

Exclusion Criteria:

• history of musculoskeletal disorders that significantly affect movement of the upper or lower limbs
• other significant neurological disorder
• history of dementia or cognitive impairment as found with UBACC (or MacCAT-CR)
• post-operative complications or adverse effects