It's Not Just Bombs: How Training Range Blasts Are Causing Invisible Brain Injuries in Soldiers

When most people think about military brain injuries, they picture IED explosions in Iraq or Afghanistan. But the emerging science tells a different and more troubling story: thousands of service members may be sustaining cumulative brain damage from routine training activities that were never considered dangerous.

The roles at highest exposure

Hand grenade range instructors, heavy weapons operators, artillery crew members, and breaching specialists are exposed to blast overpressure repeatedly — sometimes hundreds or thousands of times — throughout their careers. Each individual exposure may fall below the threshold for a diagnosed concussion, but the cumulative effect is increasingly linked to neurological symptoms and brain pathology. Research published in The Lancet Neurology and the New England Journal of Medicine has documented neuropathological changes in military personnel with histories of repetitive low-level blast exposure.

The case that forced public attention

The case that brought this issue into tragic public view was the Lewiston, Maine mass shooting in October 2023. The perpetrator was a hand grenade range instructor who had been exposed to thousands of low-level blasts over his military career. His postmortem brain examination, conducted by researchers at Boston University’s CTE Center (as reported by the New York Times), revealed traumatic brain injury consistent with cumulative blast exposure — changes similar to what has been found in studies of other military blast-exposed individuals.

Why “mild” is the most dangerous category

According to DVBIC, 83% of military TBIs are classified as mild — precisely the category where baseline comparison is most important because mild TBI produces no visible abnormalities on CT or MRI scans. The only way to detect subtle cognitive changes from cumulative exposure is to compare current performance against a known healthy baseline over time.

The detection strategy that works

This is precisely the kind of injury that baseline testing is designed to detect early. A single post-blast cognitive test might look normal. But serial testing over time — comparing each year’s results against the original baseline — can reveal progressive cognitive decline that would otherwise go unnoticed until symptoms become severe enough to disrupt daily functioning.

Our position

At Headquarters, we support expanded baseline testing for all occupations with blast, impact, or repetitive head trauma exposure — military and civilian alike. Early detection through longitudinal baseline comparison is the most effective way to intervene before cumulative damage becomes irreversible. For the policy context, see the Pentagon’s 2024 baseline mandate.

Frequently asked questions