Noninvasive Brain Stimulation in Mild Cognitive Impairment and Dementia

Not Applicable

Completed

Conditions: Mild Cognitive Impairment
Dementia
Alzheimer Disease

Interventions: Device: Active Transcranial direct current stimulation (STARStim 8)
Device: Sham Transcranial direct current stimulation (STARStim 8)

Registration Number: NCT05270408

Lead Sponsor: University of Texas Southwestern Medical Center

Brief Summary: The research objective of this study is to examine the efficacy of HD-tDCS to the preSMA/DACC region and its influence on verbal episodic memory in patients with MCI or dementia after 10 sessions of HD-tDCS. There will be three treatment arms: two active HD-tDCS (1 mA or 2 mA) and a sham group. A verbal episodic memory task will be completed at baseline, immediately following the last HD-tDCS session, and a 2-month follow-up.

Detailed Description: This is a pilot study being done to attempt to improve verbal episodic memory in persons with mild cognitive impairment (MCI) and dementia. Although the hippocampus is a brain structure most often associated with early deficits in MCI and dementia, the pre-supplemental motor area (preSMA) and dorsal anterior cingulate cortex (DACC) have been shown to play a role in verbal episodic memory for such patients. The purpose of this study is to examine the efficacy of high-definition transcranial direct current stimulation (HD-tDCS) to the preSMA/DACC region and its influence on verbal episodic memory in patients with MCI and dementia. Entraining the preSMA/DACC circuit with 10 sessions at one of two levels of HD-tDCS will allow the researchers to investigate whether neuromodulation may be used to improve verbal episodic memory. Participants will receive 10 sessions at one of two levels of active stimulation (1 mA or 2 mA anodal HD-tDCS targeting preSMA/DACC for 20 min) or sham across 2 weeks. The device is used to deliver high definition transcranial direct current stimulation to targeted regions. A verbal episodic memory task will be completed at baseline, immediately following the last HD-tDCS session, and a 2-month follow-up. The investigators plan to recruit English-speaking participants aged 50 years and older with MCI and dementia. Participants will be randomized into HD-tDCS conditions.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 33

Inclusion Criteria

Age 50 and older
Fluent in English
Active diagnosis of MCI or dementia

Exclusion Criteria

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)

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Active stimulation at 2mA	Active Transcranial direct current stimulation (STARStim 8)	Participants will receive 2 mA active HD-tDCS for 20 minutes.
Active stimulation at 1mA	Active Transcranial direct current stimulation (STARStim 8)	Participants will receive 1 mA active HD-tDCS for 20 minutes.
Sham group	Sham Transcranial direct current stimulation (STARStim 8)	Participants will receive sham HD-tDCS for 20 minutes, meaning no stimulation.

Primary Outcome Measures

Name	Time	Method
Change in Score on the Rey Auditory Verbal Learning Test (RAVLT)	Baseline, immediately following last treatment session, and 2-months post treatment	The RAVLT is a verbal episodic memory task where a list of 15 words is read aloud for 5 consecutive trials followed by a 20 minute delayed recall trial. The number of items recalled immediately after each trial are summed to create a total learning score, ranging from 0-75. Also, the number of items recalled for the delayed trial are recorded as a delayed recall score, ranging from 0-15. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better episodic memory performance. Changes from baseline for the total learning and delayed recall scores at the last HD-tDCS session and the 2-month follow-up will be measured as the primary outcomes.

Secondary Outcome Measures

Name	Time	Method
Change in Score on the Brief Visuospatial Memory Test-Revised (BVMT-R)	Baseline, immediately following last treatment session, and 2-months post treatment	The BVMT-R is a visual episodic memory task where 6 simple designs are shown for 10 seconds in a 2 x 3 matrix for 3 learning trials followed by a 25-minute delayed recall trial. The number of items recalled immediately after each trial are summed to create a total learning score, ranging from 0-36. Also, the number of items recalled for the delayed trial are recorded as a delayed recall score, ranging from 0-12. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better visual episodic memory performance. Changes from baseline for the total learning and delayed recall scores at the last HD-tDCS session and the 2-month follow-up will be measured.
Change in Score on the Boston Naming Test Short Form	Baseline, immediately following last treatment session, and 2-months post treatment	The Boston Naming Test Short Form is a 30 item version of the task (odd and even item versions of the full test) and a measure of language. The subject is shown pictures of objects and is required to correctly name them as quickly as possible. The outcome measure for this task is the total number of correct responses, ranging from 0-30. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better performance. Changes from baseline to the last HD-tDCS session and the 2-month follow-up will be measured.
Change in Score on the Delis Kaplan Executive Function System (DKEFS) Phonemic Fluency	Baseline, immediately following last treatment session, and 2-months post treatment	The DKEFS phonemic verbal fluency task is a measure of language. The subject is required to name as many words as possible that begin with specified letters within 1 minute. Three different letter trials are completed. The outcome measure for this task is the total number of correct responses across the trials, ranging from 0-90. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better performance. Changes from baseline to the last HD-tDCS session and the 2-month follow-up will be measured.
Change in Score on the Delis Kaplan Executive Function System (DKEFS) Semantic Fluency	Baseline, immediately following last treatment session, and 2-months post treatment	The DKEFS semantic verbal fluency task is a measure of language and involves 3 conditions. The subject is required to name as many animals and people names as possible within 1 minute. The outcome measure for this task is the total number of correct responses for both conditions combined, ranging from 0-90. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better performance. Changes from baseline to the last HD-tDCS session and the 2-month follow-up will be measured.
Change in Score on the Trail Making Test	Baseline, immediately following last treatment session, and 2-months post treatment	The Trail Making Test is a measure of cognitive flexibility and executive functions. The task requires the subject to as quickly as possible complete two conditions, involving number sequencing and then number-letter switching. The outcome measure for this task is the time in seconds to complete the number-letter switching condition, ranging from 15-300. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better performance. Changes from baseline to the last HD-tDCS session and the 2-month follow-up will be measured.
Change in Score on the Southwestern Assessment of Processing Speed	Baseline, immediately following last treatment session, and 2-months post treatment	The Southwestern Assessment of Processing Speed is a measure of psychomotor processing speed. The subject is required to transcribe numbers to their corresponding written symbol as quickly as possible within 60 seconds. The outcome measure for this task is the total number of correct responses, ranging from 0-75. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better performance. Changes from baseline to the last HD-tDCS session and the 2-month follow-up will be measured.
Change in Score on the DKEFS Color-Word Interference Test	Baseline, immediately following last treatment session, and 2-months post treatment	The DKEFS Color-Word Interference test is a measure of information processing speed and complex attention. The task requires the subject to as quickly as possible complete four conditions, involving color naming, word reading, response inhibition, and then switching back-and-forth between two response patterns. The outcome measures for this task was the response inhibition trial and the switching trial, which are scored as the time in seconds to complete the conditions, ranging from 20-180. Scores were converted to standardized scores (T-scores) using normative data, ranging from 2-86. Higher scores reflect better performance. Changes from baseline to the last HD-tDCS session and the 2-month follow-up will be measured.