Invasive Approach to Model Human Cortex-Basal Ganglia Action-Regulating Networks

1. Age > 18
2. Rigid-akinetic subtype of Parkinson's disease, diagnosed by a movement disorders neurologist
3. Clinical indications, as deemed by a multidisciplinary team of neurologists and neurosurgeons, for deep brain stimulation surgery, including motor fluctuations, difficult-to-control-dyskinesias, unpredictable off-times, and/or dystonia
4. Preoperative MRI without cortical or subdural adhesions or vascular abnormalities
5. Subject is medically fit for surgical intervention, as deemed by a primary care physician

Exclusion Criteria:

1. Inability or unwillingness to tolerate 20 minutes and up to 40 minutes of additional operative time
2. Patient with history of secondary Parkinsonism, stroke, or progressive central nervous system disease other than Parkinson's disease.
3. Subject is at high risk for surgical complications such as active systemic infection, coagulation disorders (such as the use of anti-thrombotic therapies) or platelet count below 100,000.
4. Subject is taking chronic anticoagulants or antiplatelet agent or subject has an abnormally elevated preoperative coagulation profile (either (Partial Thromboplastin Time) PTT or prothrombin time/INR).
5. Patients with recent use (within one week) of anticoagulant or antiplatelet agent use
6. Subject has history of bleeding or immune compromise.
7. Subject has history of implant-related infection.
8. Subject has a prior history of seizures or epilepsy.
9. Subject has a clinically significant or unstable medical condition including uncontrolled systemic hypertension with values above 170/100; cardiac or pulmonary disease; uncorrected coagulation abnormalities; diabetes; or any condition that would render the patient unable to safely cooperate with the study tests as judged by the screening physician.
10. Subject has a significant abnormality on preoperative brain MRI
11. Subject has had prior craniotomy or brain surgery.
12. Subject has significant memory impairment (based on Montreal Cognitive Assessment (MoCA) \< 23).

13. Subject has a disease or condition that prevents understanding or communication of informed consent, study demands, and testing protocols, including:

    1. Cognitive decline including diagnosed forms of dementia and/or progressive neurologic disease
    2. Does not speak a principal language associated with the region
    3. Hearing loss that prevents adequate communication with researchers.
14. Subject has moderate or severe depression (HAMD ≥ 17)
15. Subject is implanted with any neuromodulation device in the head including, but not limited to cochlear implant, deep brain stimulator, or auditory brain implant.