Neocortical Microarchitecture of Executive Function

Inclusion Criteria: 1. Diagnosis of Parkinson's disease and refractory to medications requiring deep brain stimulation 2. Aged 45-85 3. Able to provide informed consent 4. Normal neuropsychiatric evaluation that includes tests of executive function demonstrating no greater than mild impairments, within expectation for Parkinson's disease. 5. Medically able to undergo deep brain stimulation surgery as evaluated by study neurosurgeon. 6. Surgical plan includes an entry point that can safely be placed in the dorsal lateral PFC. 7. Able to tolerate awake deep brain stimulation surgery with a plan for the case to be done awake. 8. Able to tolerate 25 additional minutes of awake surgery. 9. Able to participate and comply with tasks adequately, including instructions provided in English. Exclusion Criteria: 1. Moderate, or severe cognitive impairment as determined by a licensed neuropsychologist during routine neuropsychological evaluation. 2. Inability to tolerate awake surgery as determined by the treating neurologist and study neurosurgeon. 3. Inability to safely access the dorsal lateral prefrontal cortex for an entry location. 4. Moderate or severe cognitive impairment or executive function deficits as determined by neuropsychological testing. 5. Evidence of a clinically significant abnormality on preoperative imaging.