战争留下的不只是身体的创伤

MELISSA BLOCK, host: Mild Traumatic（a.创伤的） Brain Injury, or TBI, has become a signature injury of the wars in Iraq and Afghanistan. Tens of thousands of troops have suffered concussions（n.脑震荡，震动） that left them with TBI. And doctors have struggled to determine when or if a person with the condition can return to battle.

Blake Farmer of member station WPLN takes us to Fort Campbell, Kentucky, where physicians are simulating stressful combat situations. The goal is to better understand TBI.

Sergeant JOSHUA THURMAN: Jesus. Okay.

BLAKE FARMER: An explosion catches Sergeant Joshua Thurman by surprise, as he and a team of recovering soldiers sweep a gravel(n.沙砾，砾石) road for explosives at a training site on Fort Campbell. Armed with paintball（彩弹射击）guns, they take periodic fire from pretend insurgents（叛乱分子）.

FARMER: The last time most of these veterans heard bomb blasts and gunshots was the day they almost died in Afghanistan.

Sgt. THURMAN: Manning the .50 cal and there was an explosion, and the concussion got me. And came to find out I did have a TBI, but I also lost the hearing in my left ear.

FARMER: Hearing loss alone may keep Thurman from going back to the frontline. But the lingering（拖延的;逗留不去的） effects of a concussion also get in the way for soldiers. Memory loss, mood swings(情绪波动) and balance problems make returning to duty after a TBI difficult, but not impossible.

Between each battlefield simulation, physical therapist Tamara Moreland tests each soldier's balance.

Ms. TAMARA MORELAND (Physical Therapist): You put your arms straight out in front of you, close your eyes, 50 steps in-place, stay where you stop.

FARMER: Physical symptoms of TBI tend to get worse under stress. Moreland wants to see how much worse.

Until now, returning to duty took a doctor like David Twillie looking at a few charts and signing off. That's changing.

Dr. DAVID TWILLIE (Director, Traumatic Brain Injury Center, Fort Campbell): We said soldiers are making life and death decisions, so doesn't it make sense to use demonstrated competence as the standard for returning someone to duty?

FARMER: Twillie directs Fort Campbell's TBI clinic, singled out as a national model by the Pentagon. Patients here must demonstrate their competence through pencil-and-paper tests, as well as new real-life exercises.

Most soldiers who get to these simulations will return to duty, Twillie says. But some soldiers appear ready to go back on paper when they're really not.

Dr. TWILLIE: In fact, very recently had a soldier that really had a desire to stay in, had done well on all of our pencil and pad, our computerized tests and all of our simulations. But when all of the different sights, sounds, and smells, everything that's related to combat, he just wasn't able to change his focus. He could focus on one thing but he couldn't really switch when the conditions changed to something else. And that's very important in combat.

FARMER: The audio of a battle scene, lifted from "Saving Private Ryan," is pumped into this black box of a room. A strobe light(频闪灯) imitates the flashes of gun muzzles(枪(炮)口). Three mannequins(假人) lie in pools of fake blood with amputated limbs scattered around them.

Sergeant JEREMY COLE (Trainer, Fort Campbell Warrior Resiliency Recovery Center): All right, Staff Sergeant, we've got more than one casualty. Let's go.

FARMER: Trainer Jeremy Cole watches to see if soldiers can complete a series of tasks in the correct order, even when rattled. They put in chest tubes, tighten tourniquets(n.止血带).

Unidentified Man #2: On your knees. We're going to need...

Sgt. COLE: Catch your breath. We're going to need probably blood. He lost a lot of blood. We're going to need another stretcher.

FARMER: As the sound goes down and the lights come up, Staff Sergeant Nicholas Smith stands in a pool of red looking at his hands.

Staff Sergeant NICHOLAS SMITH: I mean I've had soldiers' blood on my hand before, so it's just like, you know, it takes you back there.

FARMER: There is blood everywhere in this room. And you're saying this is no exaggeration.

SSgt. SMITH: When you have a massacre (n.大屠杀, 残杀) like this, it's everywhere. So...

Sergeant PATRICK CUMMINGS: The only difference is no one is crying. No one is screaming, Mom, or get me out of here.

SSgt. SMITH: That's the only difference.

FARMER: That's Sergeant Patrick Cummings, a big guy with a serious face, who says he's surprised by his own reaction.

Sgt. CUMMINGS: It kind of brought tears because of just - I was there. I was one of these patients before and it just hit home.

FARMER: Despite the flashback, Cummings wants to deploy (vt.部署，调动) again. As a TBI survivor, he'll be in good company. The Department of Defense estimates roughly 115,000 servicemembers have experienced one of these mind-altering injuries.

For NPR News, I'm Blake Farmer in Nashville.