The purpose of the study is to test whether low level electric stimulation, called transcranial Direct Current Stimulation (tDCS), on the part of the brain (i.e., pre-supplementary motor area) thought to aid in memory will improve verbal retrieval in civilian (non-military, non-veteran) participants with histories of traumatic brain injuries. The primary outcome measures are neuropsychological assessments of verbal retrieval, and the secondary measures are neuropsychological assessments of other cognitive abilities and electroencephalography (EEG) measures. Additionally, the study will examine the degree to which baseline assessments of cognition, concussion history, structural brain imaging, and EEG predict responses to treatment over time, both on assessments administered within the intervention period and at follow-up.
Using two treatment arms, the study will examine improvement of verbal retrieval and other cognitive deficits associated with remote traumatic brain injury by comparing (1) 1 milliamp transcranial direct current stimulation (tDCS) active treatment applied to presupplementary motor area for 20 minutes over 10 sessions to (2) sham tDCS following the same schedule. Additionally, after completing the initial active or sham treatment and 2-month follow-up testing sessions, participants will be invited back for newly assigned treatment conditions, 20 minutes over 10 sessions and will be re-evaluated at 2-months follow-up testing sessions. Civilians with histories of traumatic brain injuries and observed cognitive deficits will be randomly assigned to one of the two treatment arms (and re-assigned for the second round of intervention, as described above). Primary outcome verbal retrieval measures, secondary neuropsychological and electroencephalography (EEG) measures, and prescreening assessments for study concussion history and contraindications for treatment will be collected prior to being assigned to a treatment arm (i.e., baseline). Magnetic resonance imaging of the brain will be obtained only at the baseline assessment. Primary outcome verbal retrieval measures and secondary neuropsychological and electroencephalography (EEG) measures will be collected after treatment session 10 and one time following treatment competition (i.e., 2-months). For participants who complete the second round of intervention, primary outcome verbal memory measures and secondary neuropsychological and electroencephalography (EEG) measures will be collected again after treatment session 10 and one time following competition of the second treatment (i.e., 2-months). This study was funded by NIH/NIDCD under grant number \[1K99DC020185\]. Federal funding concluded on 11/30/2024.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
TRIPLE
Enrollment
5
Transcranial direct current stimulation will be delivered via a Neuroelectrics Starstim tES. Stimulation will consist of 1 milliamp stimulation, with anodal stimulation delivered at electrode Fz (International 10/10 System for electroencephalography electrode placement) and electrodes F7, FP1, FP2, and F8 as returns. All electrodes are 1 cm diameter Ag/AgCl electrodes and make contact with the scalp via connective gel. Stimulation will linearly ramp up from 0 milliamps to 1 milliamp over 60 seconds, then remain at 1 milliamp of stimulation over 20 minutes, and finally ramping down at to 0 milliamps over 60 seconds.
Sham transcranial direct current stimulation will be delivered via a Neuroelectrics Starstim tES. The sham setup will consist of anodal electrode Fz (International 10/10 System for electroencephalography electrode placement) and electrodes F7, FP1, FP2, and F8 as returns. All electrodes are 1 cm diameter Ag/AgCl electrodes and make contact with the scalp via connective gel. Stimulation will linearly ramp up from 0 milliamps to 1 milliamp over 60 seconds, ramp down to 0 milliamps over 60 seconds and then be left off for 20 minutes.
The University of Texas at Dallas
Dallas, Texas, United States
University of Texas Southwestern Medical Center
Dallas, Texas, United States
The Controlled Oral Word Association Test
Evaluation of treatment differences (active versus sham) in change on the Control Word Association Test. Metric: Total Number of Correct Items Generated for three different letters. Total Range 0 (minimum) - 200 (maximum). Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
Category Fluency
Evaluation of treatment differences (active versus sham) in change on Category Fluency. Metric: Total Number of Correct Items Generated for Animal. Total Range 0 (minimum) - 100 (maximum). Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
The Boston Naming Test
Evaluation of treatment differences (active versus sham) in change on The Boston Naming Test - 30 items. Metric: Total Number of Correct Items Generated. Total Range 0 (minimum) - 30 (maximum). Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
Semantic Object Retrieval Test
Evaluation of treatment differences (active versus sham) in change in Semantic Object Retrieval Test. Metric: Total Number of Correct Retrievals. Total Range 0 (minimum) - 32 (maximum). Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
The Delis Kaplan Color Word Interference Test, Naming
Evaluation of treatment differences (active versus sham) in change on the Delis Kaplan Color Word Interference Test. Metric: Time - seconds to Name Items. Total Range 0 (minimum) - 150 (maximum). Longer time indicates worse performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
The Delis Kaplan Color Word Interference Test, Reading
Evaluation of treatment differences (active versus sham) in change on the Delis Kaplan Color Word Interference Test. Metric: Time - seconds to Name Items. Total Range 0 (minimum) - 150 (maximum). Longer time indicates worse performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
The Delis Kaplan Color Word Interference Test, Inhibition
Evaluation of treatment differences (active versus sham) in change on the Delis Kaplan Color Word Interference Test. Metric: Time - seconds to Name Items. Total Range 0 (minimum) - 150 (maximum). Longer time indicates worse performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
The Delis Kaplan Color Word Interference Test, Inhibition and Switching
Evaluation of treatment differences (active versus sham) in change on the Delis Kaplan Color Word Interference Test. Metric: Time - seconds to Name Items. Total Range 0 (minimum) - 240 (maximum). Longer time indicates worse performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
Rey Auditory Verbal Learning Test and Alternative Lists, Total Learning
Evaluation of treatment differences (active versus sham) in change in Rey Auditory Verbal Learning Test. Metric: Number of Total learning items and Correct Recalls. Total Range 0 (minimum) - 75 (maximum). Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
Rey Auditory Verbal Learning Test and Alternative Lists, Delayed Recall
Evaluation of treatment differences (active versus sham) in change in Rey Auditory Verbal Learning Test. Metric: Total Number of Delayed Recall items and Correct Recalls. Total Range 0 (minimum) - 15 (maximum). Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
The Trail Making Test - Part A
Evaluation of treatment differences (active versus sham) in change on the Trail Making Test (Parts A\&B). Metric: Time to Solution. Total Range 0 (minimum) - 300 (maximum). Longer time indicates worse performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
The Trail Making Test - Part B
Evaluation of treatment differences (active versus sham) in change on the Trail Making Test (Parts A\&B). Metric: Time to Solution. Total Range 0 (minimum) - 300 (maximum). Longer time indicates worse performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
Digit Span Forward
Evaluation of treatment differences (active versus sham) in change in Digit Span Forward. Metric: Memory Span, a composite score of how many numbers are repeated correctly in a forward order. Z = 0 is the normed average, with positive Z values better and negative Z values worse than the normed average.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
Digit Span Backward
Evaluation of treatment differences (active versus sham) in change in Digit Span Backward. Metric: Memory Span, a composite score of how many numbers are repeated correctly in a backward order. Z = 0 is the normed average, with positive Z values better and negative Z values worse than the normed average.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
Rey-Osterrieth Complex Figure Test - Delayed Recall
Evaluation of treatment differences (active versus sham) in change in Rey-Osterrieth Complex Figure Test scores. Metric: Score. Total Range 0 (minimum) - 36 (maximum). This is a summed score of the number and accuracy of complex figure features captured. Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.
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The Digit Symbol Substitution Test
Evaluation of treatment differences (active versus sham) in change on the Digit Symbol Substitution Test. Metric: Number of Items. Total Range 0 (minimum) - 135 (maximum). Larger numbers indicate better performance.
Time frame: Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment.