Acquired Brain Injury, Cognitive Change, Traumatic Brain Injury, Word Finding Difficulty
Conditions
Keywords
electroencephalography, transcranial direct current stimulation, Cognition
Brief summary
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.
Detailed description
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). 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).
Interventions
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.
Sponsors
Study design
Masking description
Participants, assessors, and technicians interacting with participants will be blind to assigned conditions.
Intervention model description
Participants will be randomly assigned to 1 of 2 treatment arms: (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, all participants will be invited back for newly assigned treatment conditions, 20 minutes over 10 sessions and will be and re-evaluated at 2-months follow-up testing sessions.
Eligibility
Inclusion criteria
* Between the ages of 18-85 * Traumatic brain injury more than a year prior to study participation * Word finding difficulty since the brain injury * Fluent in speaking and reading English.
Exclusion criteria
* Implanted/electronic device, such as a pacemaker, metallic cranial or intracranial implant (e.g., ventriculoperitoneal shunt), or a neurostimulator (e.g., vagus nerve stimulator, spinal stimulator, deep brain stimulator, etc.). * Skull defects * History of a psychological or neurological disorder, including, dementia of any type, epilepsy or other seizure disorders, post-traumatic stress disorder, brain tumor, present drug abuse, stroke, blood vessel abnormalities in the brain, Parkinson's disease, Huntington's disease, or multiple sclerosis. * Inability to give informed consent * Military personnel or Veteran * Currently pregnant * Not fluent English speaker
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The Controlled Oral Word Association Test | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change on the Control Word Association Test, including both letter and category fluency. Metric: Number of Correct Items Generated |
| The Boston Naming Test | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change on The Boston Naming Test. Metric: Number of Correct Items Generated. |
| Rey Auditory Verbal Learning Test and alternative lists | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change in Rey Auditory Verbal Learning Test. Metric: Number of Total learning items and Correct Recalls. |
| The Delis Kaplan Color Word Interference Test | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change on the Delis Kaplan Color Word Interference Test. Metric: Time to Name Items |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The Trail Making Test (Parts A & B) | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change on the Trail Making Test (Parts A\&B). Metric: Time to Solution |
| Digit Span Forward & Backward | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change in Digit Span Forward \& Backward. Metric: Memory Span |
| Rey-Osterrieth Complex Figure Test | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change in Rey-Osterrieth Complex Figure Test scores. Metric: Score 0 to 36, the higher the better |
| The Digit Symbol Substitution Test | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in change on the Digit Symbol Substitution Test. Metric: Number of Items |
| Task-based electroencephalography (EEG) markers during a Go-NoGo task | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in EEG change on a Go-NoGo task with different levels of perceptual/semantic complexity. Metric: event-related potentials and time frequency changes. |
| Task-based electroencephalography (EEG) markers during a Semantic Object Memory Retrieval task | Treatment differences (active versus sham) in change from Baseline to immediately and 2-months Post-Treatment. | Evaluation of treatment differences (active versus sham) in EEG change on a Semantic Object Retrieval task. Metric: event-related potentials and time frequency changes. |
Countries
United States
Contacts
The University of Texas at Dallas