WASHINGTON, September 11 — The Pentagon is widening its effort to understand what blast exposure does to service members, and the technical reality is proving less comfortable than the old assumptions. Alyssa Hundrup, discussing the department’s evolving approach to brain health on The Federal Drive with Terry Gerton, said the department “really has had to change the way it is thinking and its approach to brain health effects from blast over pressure.” The shift is not cosmetic.
Past understanding held that large events — explosives, the obvious stuff — caused injury. Learning over time has shown a serious health risk from low-level exposures: the repeated, daily kind that come with firing weapons, whether in training exercises or military operational settings.
The physics of a pressure wave
Under the hood, the mechanism is straightforward enough. Firing a weapon such as a .50 caliber rifle or shoulder-fired rifles releases energy that causes sudden pressure waves. Those waves can travel through the skull and cause micro injuries to the brain.
Smaller and repeated exposures over time can have cumulative effects and cause immediate symptoms such as headaches and slowed reaction time, and over time even memory loss and in some cases traumatic brain injuries. That is the detail that matters.
The injury does not require a single dramatic event to register.
Assessment, tracking, and a sensor effort in its infancy
On monitoring, Hundrup described an approach spanning prevention, mitigation, awareness and treatment. It begins with cognitive assessments, which measure the speed and accuracy of attention and memory, ideally establishing a baseline assessment of a service member that can be reassessed after an event or on a regular basis — one of the primary goals of the department’s new requirements. A second element is exposure tracking, which in an ideal scenario would record each exposure: what weapon, when, and how much.
The department is working toward sensors to track actual exposures so a service member could document them over the life of their career and use the record for identifying and eventually treating an effect if needed. Hundrup cautioned the sensor effort is in its infancy.
Asked whether the department has the capacity to build a tracking mechanism accounting for cumulative injury over a career, Hundrup said some specialties are considered higher risk than others and a list of those has been identified. She called that a very important start that will need evaluation, evolution and continued attention. She noted a decent understanding of blast overpressure for land activities, while understanding of blast overpressure in air environments and at sea or on water is in its infancy.
There is potential for blast overpressure to touch just about every service member, she said, and the review found the department does not yet have the resources, having had challenges with staff, technology and the ability to get its arms around every service member. It has taken a prioritized approach focused on high-risk service members, which she welcomed, but she said the department fundamentally needs more.
Gerton noted that brain injuries are far more familiar than they once were, between football players and combat injuries, and that military personnel by their nature have more exposure risk to blast brain injuries. He also observed that such injuries were once associated with hearing loss issues rather than brain injuries. Listeners can reach Terry and the Federal Drive producers with feedback and story ideas at [email protected].
What to watch next is the sensor programme and the high-risk specialty list. Both are early, and both will determine whether the department can move from counting exposures to treating their cumulative effects.
