Noninvasive Brain Stimulation on Memory in Individuals With Mild Cognitive Impairment and History of Brain Injury

Study Overview
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Brief Summary
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The study will examine the efficacy of high definition transcranial direct current stimulation (HD-tDCS) and its influence on episodic memory in patients with amnestic mild cognitive impairment and a history of Traumatic brain injury. Ten sessions of HD-tDCS to the dorsal anterior cingulate region is expected to result in improvements in episodic memory measures immediately following the last session and at a 3-month follow-up.

Official Title
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High-Definition Transcranial Direct Current Stimulation on Episodic Memory in Individuals With Amnestic Mild Cognitive Impairment and History of TBI

Conditions
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Amnestic Mild Cognitive Impairment, Traumatic Brain Injury, Mild Traumatic Brain Injury

Intervention / Treatment
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* Device: High Definition Transcranial Direct Current Stimulation
* Device: Sham HD-tDCS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 50 and older Native English speakers 12 years of education or higher Active diagnosis of aMCI History of TBI based on VA/DOD criteria Exclusion Criteria: TBI within the past 2 years Lifetime history of stroke, transient ischemic attack, heart attack, or congestive heart failure Lifetime history of epilepsy Major psychiatric disorders (i.e., posttraumatic stress disorder, bipolar disorder, schizophrenia) Substance use disorder Has metal fragments in head Taking medications that may interact with the HD-tDCS effect (i.e., amphetamines, L-dopa, carbamazepine, sulpiride, pergolide, lorazepam, dextromethorphan, D-cycloserine, flunarizine, or ropinirole)

Ages Eligible for Study
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Minimum Age: 50 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Active HD-tDCS<br>Participants will receive 10 sessions of active stimulation (1 mA anodal HD-tDCS targeting dorsal anterior cingulate region for 20 minutes) across 2 weeks, with episodic memory tasks completed at baseline, immediate follow-up after session 10, and a 3-month follow-up. | Device: High Definition Transcranial Direct Current Stimulation<br>* This wireless device delivers a very low electrical current to focused regions on the scalp in order to modulate underlying brain circuits to promote neuroplasticity. The device will be fitted onto a neoprene EEG cap, with 1 anode electrode placed and surrounded by 4 cathode electrodes in a ring pattern. Electrical stimulation will be applied using a constant voltage cortical stimulator (Model D185, Digitimer Ltd, UK, maximal output 1000 V/1.5 A) with single square-wave 50-μs pulses (0.1 A/μs rise time).<br>|
| Sham Comparator: Sham HD-tDCS<br>Participants will receive 10 sessions of sham stimulation across 2 weeks, with episodic memory tasks completed at baseline, immediate follow-up after session 10, and a 3-month follow-up. | Device: Sham HD-tDCS<br>* Sham HD-tDCS<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean change from baseline in episodic memory functioning immediately following the last HD-tDCS session and at 3-month follow-up | Episodic verbal memory will be assessed with the Hopkins Verbal Learning Test-Revised (HVLT-R). This measures rate of learning for verbal material and the amount retained after a delay. Episodic visual memory will be assessed with the Brief Visuospatial Memory Test-Revised (BVMT-R). This measures rate of learning for visual material and the amount retained after a delay. Both measures provide standardized scores based on a normative sample adjusted for key demographic factors, with higher scores reflecting better performances. | Baseline, immediately following last HD-tDCS session, and again at 3-month follow-up |