The purpose of this study is twofold: 1) Develop norms for measures of inner ear function and psychological health, and 2) Examine the feasibility of using the MINDGAPS system (a remote monitoring system) to track progress during physical therapy or rehabilitation for inner ear problems following a concussion or mild Traumatic Brain Injury.

The intersection between vestibular disturbance and psychological health provides a unique clinical opportunity to address both the modifiable symptoms of vestibular disturbance as well as psychological health. This project aims to advance our understanding of the causal link between vestibular disturbance and poor psychological health and aligns directly with the Traumatic Brain Injury and Psychological Health Research Program (Funding Opportunity: W81XWH-21-TBIPHRP-TRA). Specifically, the proposed research is responsive to each of the three focus areas: Understand- this project is designed to advance the understanding of an established link between vestibular disturbance (e.g., dizziness and poor balance) and poor psychological health (e.g., anxiety, depression, and social isolation) in survivors of mild traumatic brain injury (mTBI). Prevent- the MINDGAPS system allows for precise assessment of dynamic visual acuity (computerized dynamic visual acuity [cDVA]) and postural sway (instrumented balance accelerometry measure [iBAM]), two objective and extensively validated surrogates of vestibular health. Additionally, MINDGAPS uses these measures to inform care decisions via a user-friendly web application. Treat- vestibular assessment is key to effective vestibular care, as it allows for personalization of treatment programs and monitoring progress over time.

Objective/Hypothesis:

The overall objective of this project is two-fold: 1) Test the preliminary efficacy of the MINDGAPS system to improve psychological health and vestibular disturbance in active-duty and Veteran Service Members (SM) with history of mTBI and 2) refine the MINDGAPS system by developing military-specific normative data and using Community-Based Participatory Research (CBPR) to incorporate the lived experiences of mTBI survivors, their caregivers, and clinicians in the design of the MINDGAPS technology and intervention.

Specific Aims:

Specific Aim 1 (Preliminary Efficacy): Examine the preliminary efficacy of the MINDGAPS system to improve psychological and vestibular health in active-duty and Veteran SM with sub-acute and chronic mTBI.

Specific Aim 2 (Military-specific Normative Data): Collect a cross-sectional sample of cDVA, iBAM, and other relevant measures in active-duty and Veteran Service Members across three different stages of mTBI-no diagnosed history of mTBI, sub-acute mTBI (2-6 months), and chronic mTBI (>6 months)-for the development of normative values in military-specific populations.

Specific Aim 3 (Refinement of MINDGAPS): Utilize CBPR to refine and improve the MINDGAPS system for different stakeholders (SM, caregivers, and clinicians) and position MINDGAPS for examination in a large-scale clinical trial as well as translation into clinical practice.

Study Design:

Aim 1: Using a single-cohort (N=36) double-baseline design, all participants will be tested twice during a no-intervention baseline period, then once following a 6-week course of vestibular training with the MINDGAPS system. Efficacy will be determined by comparing change during the baseline period to change over the course of the intervention period. Aim 2: A large sample of active-duty and Veteran SM (N=300) will be tested in a single, cross-sectional assessment to build military-specific normative vestibular data. Aim 3: We will use a convergent mixed-methods analysis of study participant feedback, in combination with quantitative results and stakeholder engagement, to drive refinement of the MINDGAPS system throughout the study period.

Impact:

Signs of vestibular disturbance are the most commonly reported symptoms following mTBI, and vestibular disturbance is causally implicated in the development of poor psychological health following mTBI. Interventions aimed at improving vestibular disturbance can improve debilitating symptoms such as poor balance and dizziness. The completion of this study will move MINDGAPS to a technology readiness level of 8, preparing it to be studied in a large clinical trial in the next phase of work.

Relevance to Military Health:

Interventions aimed at improving vestibular disturbance would have profound impacts on both active-duty SM (inability to visually focus during dynamic tasks- e.g., field of fire) and Veterans (increased risk of falls). Furthermore, the MINDGAPS system enables rapid and precise assessment of vestibular functioning at low cost and therefore has tremendous potential to enhance the delivery of clinical services within a number of active-duty environments including far-forward military settings or Veterans living in rural areas.

Inclusion Criteria:

• Veteran or Active Duty Military Service Member
• Ability to stand independently
• Legally autonomous and able to self-consent

Exclusion Criteria:

• Acute head injury (within the previous 2 months)
• History of moderate or severe head injury (i.e., loss of consciousness greater than 30 minutes or post-traumatic amnesia greater than 1 day)
• Current diagnosis of spine disorders in the neck
• Diagnosis of problems with the arteries in your neck
• Blindness
• If you have been diagnosed with abnormal eye movements (also called "ocular motor palsy")
• If you have previously had a stroke or been diagnosed with a neurodegenerative disorder ( e.g., Parkinson's Disease, Multiple Sclerosis)
• If you have been previously diagnosed primary vestibular dysfunction ( e.g., congenital peripheral vestibular syndrome)
• If you have previously been diagnosed with a brain tumor
• If you are currently receiving physical therapy care for balance or dizziness problems