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The frequent use of explosive devices in the Iraq and Afghanistan wars has given birth to a new type of war injury: multiple mild traumatic brain injuries (mTBI). According to, recent research has shown that multiple exposures to explosions cause damage to the brain.

According to the US Defense Department’s Defense and Veterans Brain Injury Center, since 2010, over 361,000 service members have been diagnosed with some form of traumatic brain injury. The three different levels of TBI, severe, moderate, and mild, show symptoms in different ways, from memory loss and extended unconsciousness to a simple headache. Mild TBI tends to go unnoticed, one blast may not cause effects like memory loss or slurred speech, there’s really no easy way to diagnose the condition, says Alex Balbir, director of Warrior Care Network and Independence Services at the Wounded Warriors Project.

“It’s only after a few of these injuries, that you start to see the effects of the trauma like memory loss and slurred speech”.

In an effort to fill that technology gap, Timothy Bentley and his team at the Office of Naval Research’s Warfighter Performance Department, have designed a new sensor technology that could give medics on the battlefield a clearer idea of whether or not an injury actually occurred after a blast.

The coin-sized sensors, placed in service members’ helmets and tactical gear, detect the impact of a blast wave which moves faster than the speed of sound and assigns it a number, a measure of blast strength. The number is then run through an algorithm that computes how a service member was hit by a blast, which sensors were activated based on their placement, and then tells medics if the service member needs to get off the field immediately or not.

If the algorithm shows a possible mTBI, medics in the field have the service member hold a mouse-sized tool—nicknamed the “brain gauge”—that stimulates the fingertips through eraser-sized vibrators. The brain gauge vibrates each finger for a different length of time—if a service member can’t recognize which vibrations last longer, it’s highly likely he or she has suffered an mTBI.

“It’s like if you have a big earthquake hit San Francisco,” says Charles Marmar, director of the Cohen Veterans Center at New York University’s Langone Medical Center. “The bridge that falls probably won’t be the Golden Gate since it’s been fortified. The one that collapses could be the one miles away that is a bit more rickety.”

The sensors being tested by Bentley and his research which runs a price tag of $30 million and a five-year lifespan, is currently being tested on animals and at bases using electrical shockwaves. Bentley says that within the year, the technology could start being tested on those who spent (and some who continue to spend) lots of time in close proximity to explosions. Another goal, Bentley says, is to apply data collected in the military to the civilian world, such as in football where multiple concussions have been recognized to cause severe brain injuries later in life for players. Though there are no current plans to sell the sensors to institutions like the National Football League, Bentley says they’ve tested it during football games on military bases, and it seems to work.

“We’ve tested this on thousands of athletes at this point, and with those athletes, you can predict and see what sort of and how severe their injury is and how long their recovery will take,” Bentley says. “This is a big deal and we’ve made a lot of progress. It’s only a prediction and only statistical, but we now have a personal measure of your exposure.”