Biomarkers of Brain Health in Blast Overpressure Exposure (Guild Blast Ottawa, Canada 2026)
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 12
- 试验地点
- 1
- 主要终点
- Feasibility of EEG data collection during active explosive breaching, measured as the proportion of AMP Neuro recordings meeting signal-quality criteria
研究概览
简要总结
The purpose of this study is to learn whether headsets that measure brainwaves can find early signs of changes in brain health in tactical operators who train near explosive blasts.
Tactical operators are often near blasts during training. These blasts might change how the brain works over time, even if a person feels fine now. This study uses headsets that measure electrical brainwaves to see if they can detect early changes before they cause problems such as memory loss or blurred vision.
The main questions it aims to answer are:
- Can useful brainwave data be recorded during real breaching training, using sensors built into tactical hearing protection?
- Do brainwave patterns change after blast exposure, compared with a person's own Day 1 baseline?
- Do those brainwave changes line up with the amount of blast pressure a person was exposed to, with changes in balance and thinking, and with the symptoms they report?
This is an observational study. It adds no new training activities and does not change how close participants stand to a blast or how many blasts they are near. The research team observes and records during training that is already scheduled.
About 12 people taking part in Guild Solutions breaching training near Ottawa, Canada will join. The study lasts five days. Most sessions take about 5 to 10 minutes, except the Day 1 baseline session, which takes longer.
Participants will:
- Answer questions on Day 1 about sleep, stress, and habits; about any symptoms they have now, such as dizziness; and about how many blasts they were near in the past three months
- Take balance and thinking tests on a phone or tablet using the Sway Concussion app by Healthy Roster. On Day 1 these take about 15 minutes together (about 7 minutes each). On later days they take about 3 minutes each
- The balance test asks the participant to hold certain stances, such as one foot in front of the other, or standing on one foot. The thinking tests ask the participant to move the device when the screen changes color, and to remember three letters while playing a Simon-Says-style game
- Sit still for 3-minute "neural snapshot" brainwave recordings, alternating between eyes open and eyes closed. On training days these are collected in the morning, before and after each breaching exercise, and in the evening
- Answer a short symptom questionnaire in the morning, before and after each breaching exercise, and in the evening, plus a daily log of sleep and substance use
- Wear a Blast Tracker 4 blast sensor during breaching exercises
- Wear the AMP Neuro headset, which is built into tactical hearing protection, during breaching exercises. Because each breaching round has three active breachers, participants wear it in rotating groups of three, so everyone wears it at some point during the week
The headsets use passive sensors that only listen to the brain's own electrical activity. They do not send electricity into the head. These devices have not been approved by Health Canada. They are used in this study only as non-invasive tools to record research data; the study is not evaluating the devices for medical safety or effectiveness.
Anyone who feels uncomfortable or no longer wants to take part can remove the headset and leave the session at once. On the breaching range, participants should speak with an onsite instructor first, for their own safety.
Taking part is voluntary. Individual results are not shared with Guild Solutions leadership or instructors in any way that would identify a participant, and the decision to join or not join has no effect on training, performance appraisal, or employment.
详细描述
Background and rationale
Tactical operators are repeatedly exposed to sub-concussive blast overpressure during breaching training. Current safety standards rely primarily on distance-based calculations and subjective symptom reporting, which may fail to capture acute neural strain. Prior work in mild traumatic brain injury suggests quantitative EEG is sensitive to changes in Delta, Theta, and Alpha power spectra. This observational study investigates whether non-invasive EEG acquired with dry-electrode, EEG-integrated personal protective equipment can detect pre-symptomatic physiological deviation from an individual baseline in an operational training environment.
Specific aims
Validate the feasibility of collecting high-fidelity EEG during active breaching using EEG-integrated tactical hearing protection (AMP Neuro).
Identify EEG biomarkers associated with acute blast overpressure exposure, specifically Delta and Theta power increases and Alpha suppression.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Currently enrolled participant in the Guild Solutions explosive breaching training course
- •At least 18 years of age
- •Fluent in English, sufficient to understand the consent form and study instructions
- •Able and willing to provide written informed consent
- •Willing to wear the study EEG headsets during assigned portions of the study
排除标准
- •(all criteria are self-reported; medical records are not reviewed):
- •Major head injury within the past 6 months
- •Regular use of anti-seizure or sedative (sleep) medication
- •Known skin allergy or sensitivity to headset materials, including silver, silver-chloride, or vinyl
研究组 & 干预措施
Tactical operators exposed to blast overpressure
Personnel completing the Guild Solutions explosive breaching curriculum monitored with EEG, blast dosimetry, balance and cognitive assessment, and symptom report across five training days.
干预措施: Blast overpressure exposure during explosive breaching training (Other)
结局指标
主要结局
Feasibility of EEG data collection during active explosive breaching, measured as the proportion of AMP Neuro recordings meeting signal-quality criteria
时间窗: During each breaching exercise, Days 2 through 5
Percentage of AMP Neuro recording epochs retained after automated movement-artifact rejection, out of all epochs recorded during active breaching. Reported per session and aggregated across the cohort, with the proportion of sessions yielding analyzable data.
Change from baseline in normalized Delta band power
时间窗: Day 1 baseline; then morning, within 60 minutes before and within 60 minutes after each breaching exercise, and evening, Days 2 through 5
Delta band power derived from 2-minute resting-state neural snapshots recorded with the MW75 Neuro headset, with eyes-open and eyes-closed segments analyzed separately. Values are expressed as a normalized index in which 100 represents the mean of a general healthy adult reference population and scores from 75 to 125 fall within one standard deviation of that mean. The index is continuous with no fixed minimum or maximum. Higher scores indicate greater Delta band power. Because the index is centered on a population mean, neither direction represents a uniformly better or worse outcome; deviation from each participant's own Day 1 baseline in either direction is the outcome of interest. The hypothesized direction following blast overpressure exposure is an increase.
Change from baseline in normalized Theta band power
时间窗: Day 1 baseline; then morning, within 60 minutes before and within 60 minutes after each breaching exercise, and evening, Days 2 through 5
Theta band power derived from 2-minute resting-state neural snapshots recorded with the MW75 Neuro headset, with eyes-open and eyes-closed segments analyzed separately. Values are expressed as a normalized index in which 100 represents the mean of a general healthy adult reference population and scores from 75 to 125 fall within one standard deviation of that mean. The index is continuous with no fixed minimum or maximum. Higher scores indicate greater Theta band power. Because the index is centered on a population mean, neither direction represents a uniformly better or worse outcome; deviation from each participant's own Day 1 baseline in either direction is the outcome of interest. The hypothesized direction following blast overpressure exposure is an increase.
Change from baseline in normalized Alpha band power
时间窗: Day 1 baseline; then morning, within 60 minutes before and within 60 minutes after each breaching exercise, and evening, Days 2 through 5
Alpha band power derived from 2-minute resting-state neural snapshots recorded with the MW75 Neuro headset, with eyes-open and eyes-closed segments analyzed separately. Values are expressed as a normalized index in which 100 represents the mean of a general healthy adult reference population and scores from 75 to 125 fall within one standard deviation of that mean. The index is continuous with no fixed minimum or maximum. Higher scores indicate greater Alpha band power. Because the index is centered on a population mean, neither direction represents a uniformly better or worse outcome; deviation from each participant's own Day 1 baseline in either direction is the outcome of interest. The hypothesized direction following blast overpressure exposure is a decrease.
次要结局
- Association between change in EEG band power and measured blast overpressure exposure(Days 2 through 5, pairing each pre-to-post breaching EEG change with the dosimetry recorded during that exercise)
- Change from baseline in Neurobehavioral Symptom Inventory (NSI) score(Day 1 intake; then morning, within 60 minutes before and within 60 minutes after each breaching exercise, and evening, Days 2 through 5)
- Change from baseline in postural stability measured by the Sway Balance assessment(Day 1 baseline; then morning and evening, Days 2 through 5)
- Change from baseline in the Sway Reaction Time score(Day 1 baseline; then morning and evening, Days 2 through 5)
- Change from baseline in the Sway Working Memory score(Day 1 baseline; then morning and evening, Days 2 through 5)
- Association between measured blast overpressure exposure and Neurobehavioral Symptom Inventory (NSI) total score(Days 2 through 5)