NCT07010887 · Indiana University
RHI Interval Effects on Brain Health
What this study is about
Military service members frequently experience repetitive insults or impacts to the head (RHIs). The purpose of the proposed randomly assigned controlled trial is to understand how time intervals affect neurological responses to repetitive subconcussive head impacts.
View original scientific description
Military service members frequently experience repetitive insults or impacts to the head (RHIs). The purpose of the proposed randomized controlled trial is to understand how time intervals affect neurological responses to repetitive subconcussive head impacts.
Interventions
OTHER
Short Interval
A standardized and reliable soccer heading protocol will be used for the experiment. Participants perform 16 headers or kicking with 1 header per 30 seconds. The sessions (twice per week for 4 weeks) will be separated by 24 hours.
OTHER
Long Interval
A standardized and reliable soccer heading protocol will be used for the experiment. Participants perform 16 headers or kicking with 1 header per 30 seconds. The sessions (twice per week for 4 weeks) will be separated by 72 hours.
DEVICE
BrainScope qEEG
An Investigational version of the BrainScope FDA-cleared qEEG acquisition device will be used in this study. The investigational nature of the device is simply based on the code which does not produce a diagnostic result for the blinded researcher. Electrodes will be placed around the participant's forehead and scalp to acquire electrical readings of brain activity.
Primary outcome measures
Blood Biomarkers - NfL
Time frame: Baseline, 24 hours following the final heading session, 14 days following the final heading session
The primary outcome analyses will be comparing group differences (group x time interactions) in blood biomarkers, specifically NF-L (neurofilament light).
Blood Biomarkers - GFAP
Time frame: Baseline, 24 hours following the final heading session, 14 days following the final heading session
The primary outcome analyses will be comparing group differences (group x time interactions) in blood biomarkers, specifically GFAP (glial fibrillary acidic protein; nanograms per milliliter).
Blood Biomarkers - pTau
Time frame: Baseline, 24 hours following the final heading session, 14 days following the final heading session
The primary outcome analyses will be comparing group differences (group x time interactions) in blood biomarkers, specifically phosphorylated tau (picogram per milliliter).
Optical Coherence Tomography/Angiography (OCT/A) 1
Time frame: Baseline, 24 hours following the final heading session, 14 days following the final heading session
Retinal neural structure will be imaged in one or both eyes using high-definition spectral domain OCT, which will be acquired using a Zeiss Cirrus OCT scanner. The primary OCT variables examined will be macula CSF thickness (an indicator of the gain or loss of neurons or glia in the inner nuclear, ganglion cell and nerve fiber layer). Retinal vascular structure will be acquired using the OCT angiography (OCT/A) capability of the Cirrus.
Optical Coherence Tomography/Angiography (OCT/A) 2
Time frame: Baseline, 24 hours following the final heading session, 14 days following the final heading session
Retinal neural structure will be imaged in one or both eyes using high-definition spectral domain OCT, which will be acquired using a Zeiss Cirrus OCT scanner. The primary OCT variables examined will be cup-to-disc ratio (an indicator of neurodegeneration at the optic disc).
Optical Coherence Tomography/Angiography (OCT/A) 3
Time frame: Baseline, 24 hours following the final heading session, 14 days following the final heading session
Retinal vascular structure will be acquired using the OCT angiography (OCT/A) capability of the Cirrus. The primary OCT/A variable examined will be foveal avascular zone (FAZ) area reflecting the size of the central portion of the macula which contains no blood vessels, and which increases in size with loss of capillaries in the surrounding region).
Quantitative Electroencephalography (qEEG)
Time frame: Baseline, 24 hours following the final heading session, 14 days following the final heading session
An Investigational version of the BrainScope FDA-cleared qEEG acquisition device will be used in this study. The investigational nature of the device is simply based on the code which does not produce a diagnostic result for the blinded researcher. Thus, the manufacturer's full device indications/labeling document will be the same as the FDA-cleared version. An eyes-closed resting EEG will be recorded. An FDA cleared multivariate EEG marker of concussion, the Concussion Index (CI) will be used as input for this study modeling. The CI includes measures of power (absolute and relative), mean frequency, connectivity (asymmetry, coherence, phase lag, phase synchrony), complexity (fractal dimension and scale-free activity), and information theory (entropy), across and within frequency bands. Other features of interest will be included in the EEG data set. We will use all variables in a single model to analyze which variable, to what extent, contributed to group differences.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Current soccer player (intercollegiate, club, intramural, recreational).
- At least 5 years of soccer heading experience (justification below).
- Ability to provide informed consent without a legally authorized representative (LAR).
Exclusion criteria
- Any head, neck, or face injury within the 6 months prior to enrollment, including concussions, that precludes participation in contact sports.
- Participants with eye conditions or diseases that could impact the blood vessels in the eye -such as but not limited to: glaucoma, macular degeneration, diabetic retinopathy.
- Determination that the participant is unsuitable for study entry or potentially unable to complete all aspects of the study based on the judgement of the Investigator.
Where
- Bloomington, Indiana
Collaborators
United States Department of Defense, University of Rochester, Boston Children's Hospital, University at Buffalo
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 4, 2026 · Source of record for eligibility and locations