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.
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.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
TRIPLE
Enrollment
33
Participants wear a neoprene cap on their head and electrodes filled with gel are attached and will deliver 1mA to the scalp.
Participants wear a neoprene cap on their head and electrodes filled with gel are attached and will deliver 2mA to the scalp.
Participants wear a neoprene cap on their head and electrodes filled with gel are attached and will deliver no current to the scalp.
UT Southwestern Medical Center
Dallas, Texas, United States
Change in Score on the Rey Auditory Verbal Learning Test (RAVLT)
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.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment
Change in Score on the Brief Visuospatial Memory Test-Revised (BVMT-R)
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.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment
Change in Score on the Boston Naming Test Short Form
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.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment
Change in Score on the Delis Kaplan Executive Function System (DKEFS) Phonemic Fluency
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.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment
Change in Score on the Delis Kaplan Executive Function System (DKEFS) Semantic Fluency
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.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment
Change in Score on the Trail Making Test
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.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment
Change in Score on the Southwestern Assessment of Processing Speed
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.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment
Change in Score on the DKEFS Color-Word Interference Test
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.
Time frame: Baseline, immediately following last treatment session, and 2-months post treatment