Stimulating After Recovery From Traumatic Brain Injury

Study Overview
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Brief Summary
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This is a preliminary, prospective interventional study to investigate the feasibility of using transcutaneous alternating current stimulation (TACS) and transcutaneous noninvasive vagal nerve stimulation (tnVNS) after a traumatic brain injury (TBI) to improve cognitive function and decision-making.

Detailed Description
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All participants engaged in the study will participate once weekly for six weeks at Hennepin Healthcare Systems, Inc. (HHS). Each participant will be randomized into the block design of sham or tACS/tnVNS during the first three appointments or the last three appointments. While participating, both the tACS and tnVNS will be applied in accordance with the manufacturer's suggested use. Participants will complete computer-based tasks, while taking part in either the sham or tACS/tnVNS stimulation. The study is investigating the use of neuromodulation after Traumatic Brain Injury (TBI) for improved cognitive function.

Official Title
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Stimulating After Recovery From Traumatic Brain Injury

Conditions
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TBI (Traumatic Brain Injury)

Intervention / Treatment
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* Combination Product: External non-invasive stimulation
* Behavioral: COGED


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults 18 years and older Diagnosis of a mild to moderate TBI (GCS > 8 on admission) Able to perform a computerized assessment Willing to attend all scheduled appointments Able to undergo the informed consent process Healthy participants: Adults 18 years and older Able to perform a computerized assessment Willing to attend all scheduled appointments Able to undergo the informed consent process Exclusion Criteria: Open wound on scalp Severe TBI diagnosis or GCS of less than 8 on admission Non-English speaking Incarcerated Implanted defibrillator or pacemaker Visual impairment that hinders ability to complete computerized assessments Healthy subject exclusion criteria: Less than 18 years of age Open wound on scalp TBI diagnosis Non-English speaking Incarcerated Implanted defibrillator or pacemaker Visual impairment that hinders ability to complete computerized assessments

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Block design
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Sham<br>No stimulation | Behavioral: COGED<br>* The COGED task consists of the classic N-back task of working memory-based decision making, followed by a valuation phase. The N-back phase of the task allows calculation of cognitive performance of a working memory task. During valuation, participants receive titrating offers of differing amounts of money to perform different difficulty levels of the N-back. The result is an effort discounting curve used to measure the individual effort cost. Effort discounting curves show the perceived cognitive effort required to complete each level of the task relative to another (typically the 1-back).<br>|
| Active Comparator: Stimulation<br>Stimulation | Combination Product: External non-invasive stimulation<br>* The participants are randomized into the block design of sham or tACS/tnVNS during the first three appointments or the last three appointments. Eye tracking will be used to test the predominant focus of decisions during the gaze phase on costs or difficulty levels during the COGED. The study is investigating the use of neuromodulation after TBI for improved cognitive function.<br>Behavioral: COGED<br>* The COGED task consists of the classic N-back task of working memory-based decision making, followed by a valuation phase. The N-back phase of the task allows calculation of cognitive performance of a working memory task. During valuation, participants receive titrating offers of differing amounts of money to perform different difficulty levels of the N-back. The result is an effort discounting curve used to measure the individual effort cost. Effort discounting curves show the perceived cognitive effort required to complete each level of the task relative to another (typically the 1-back).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Feasibility of using non-invasive stimulation to improve Cognitive Flexibility after TBI | Using non-invasive transcranial alternating current stimulation and transcutaneous non-invasive vagal nerve stimulation; it will be determined if this study is feasible for improving cognitive recovery after mild to moderate brain injury. To determine the sum total of completion rate of study procedures. | 3 years |