Evaluation of Neurocognitive Changes in Parkinson's Disease Patients Following Acute Low Frequency Deep Brain Stimulation
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Parkinson Disease
- Sponsor
- University of Southern California
- Enrollment
- 12
- Locations
- 1
- Primary Endpoint
- Delis-Kaplan Executive Function System Verbal Fluency
- Status
- Completed
- Last Updated
- 4 years ago
Overview
Brief Summary
Rationale: Parkinson's disease patients with deep brain stimulation electrodes represent a unique opportunity to study the influence of basal ganglia on neurocognitive function.
Intervention: Patients' deep brain stimulators will be turned off or on and the frequency will be changed to either theta or gamma.
Objectives: To identify differences in higher cognitive functions with stimulation "on" and "off" and theta versus gamma frequency stimulation.
Study population: 12 patients who had previously undergone bilateral STN deep brain stimulation implantation.
Study methodology: Patients will undergo four sessions of neuropsychological testing (RNGT, verbal fluency, D-KEFS CWIT) at baseline, no stimulation, theta stimulation and gamma stimulation, in random order over one day.
Study outcomes: Test results of RNGT, verbal fluency, D-KEFS CWIT. Follow-up: none
Statistics: Test results will be analyzed using within-subjects statistical tests.
Investigators
Darrin J Lee, MD, PhD
Assistant Professor of Neurosurgery
University of Southern California
Eligibility Criteria
Inclusion Criteria
- •Male or female patients who had previously undergone bilateral STN deep brain stimulation implantation
- •Age \>18 years old
- •Stable medication regimen for at least 3 months.
- •Patient informed and able to give written consent
- •Able to comply with all testing, follow-ups and study appointments and protocols
Exclusion Criteria
- •History of epilepsy or seizure
- •History of major substance abuse
- •Patients with baseline settings at less than 1.5 V will be excluded from the study
Outcomes
Primary Outcomes
Delis-Kaplan Executive Function System Verbal Fluency
Time Frame: 5-15 minutes following stimulation frequency setting change.
Number of words per category in one minute
Delis-Kaplan Executive Function System Color Word Interference Task
Time Frame: 5-15 minutes following stimulation frequency setting change.
Time to completion of a color-word interference task
Random Number Generation
Time Frame: 5-15 minutes following stimulation frequency setting change.
Listing of 100 numbers at 1 Hz in a random order. Evan's RNG: a measure of disproportion with which one number follows another in a sequence. Scores range from 0 (equal proportion of sequence pairs) to 1 (maximum disproportion of sequence pairs). A higher score indicates a lower randomness and poorer exective function. Count score 1: a measure of propensity to count in steps of 1. The length of each sequence with steps of 1 is squared. The total of these is summed. Scores range from 0 (no sequences with steps of 1) to 100000 (all sequences with steps of 1). A higher score indicates lower randomness and poorer exective function. Count score 2: a measure of propensity to count in steps of 2. The length of each sequence with steps of 2 is squared. The total of these is summed. Scores range from 0 (no sequences with steps of 2) to 100000 (all sequences with steps of 2). A higher score indicates lower randomness and poorer exective function. Evan's RNG, count score 1 and cou