Stimulation Parameters and Non-motor Symptoms in PD Treated With DBS

Study Overview
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Brief Summary
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This study evaluates the role of subthalamic nucleus (STN) stimulation location and frequency on a range of cognitive processes in Parkinson's patients who have undergone Deep Brain Stimulation (DBS).

Detailed Description
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Pre- and post- DBS implantation brain scans will be reviewed by the study team to see if patients' DBS settings can be personalized. If so, study subjects will undergo adjustments to their DBS settings and be asked to perform cognitive tests. Some patients will be asked to come back for a second visit for brain scans.

Official Title
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Stimulation Parameters and Non-motor Symptoms in PD Treated With DBS

Conditions
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Parkinson Disease

Intervention / Treatment
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* Procedure: Personalized DBS adjustments


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Between 40 and 70 years of age, Ability to provide informed consent, Clinical diagnosis of idiopathic Parkinson disease (PD) by a movement disorders neurologist, Disease duration of at least 4 years, Treated with bilateral STN DBS for at least 3 months prior to study enrollment. Exclusion Criteria: History of prior neurosurgical intervention for PD (e.g., DBS, thalamotomy, pallidotomy) History of other central nervous system disease (excluding migraine), Presence of active psychiatric symptoms meeting Diagnostic and Statistical Manual of Mental Disorders-4th Edition (DSM-IV) criteria for Axis-I disorder on formal psychiatric evaluation, with the exception of mild depression (Beck Depression Inventory-2 score below 19), Cognitive impairment meeting Diagnostic and Statistical Manual of Mental Disorders-4th Edition (DSM-IV) criteria for dementia on formal neuropsychological evaluation, Current alcohol or substance abuse, Lack of fluency in English which would invalidate cognitive testing, Hearing or visual impairment precluding cognitive testing. Exclusion criteria for Day 2 procedures: Inability to safely undergo MRI procedure (i.e., metal objects like prostheses, pacemakers)

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Personalized DBS adjustments<br>Individualized stimulation adjustments based on pre- and post- DBS implantation MRIs | Procedure: Personalized DBS adjustments<br>* Individualized stimulation adjustments based on pre- and post- DBS implantation MRIs<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reaction time | Subjects will complete one or more measures of cognitive processing requiring speeded responses to stimuli. Changes in reaction time will be compared to 'off stimulation' | 30-60 minutes after stimulation adjustment | 
| Verbal Fluency | Change in the number words that patients generate to letter or semantic category cues will be compared to 'off stimulation' | 30-60 minutes after stimulation adjustment | 
| Finger tapping speed | Change in upper extremity speed (# of taps in 10 seconds) will be compared to 'off stimulation' | 30-60 minutes after stimulation adjustment |