ARI SHAPIRO, HOST:
Now the story of two Marines whose brains may have been injured by the powerful weapons they once fired. Military scientists are investigating whether the blast waves from these shoulder-fired weapons can damage a shooter's brain. NPR's Jon Hamilton reports that the two veterans in this story think they already know what that investigation will find.
JON HAMILTON, BYLINE: Chris Ferrari was 18 the first time he balanced a rocket launcher on his right shoulder and aimed it at a practice target.
CHRIS FERRARI: Your adrenaline's going, and you're trying to focus on getting that round to hit and listening to your guide to walk you onto the target. And then you go to squeeze that trigger and, you know...
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HAMILTON: Chris says feeling the blast wave from that weapon was the biggest rush he'd ever experienced. And his buddy Daniel, who asked that we not use his last name, had the same reaction.
DANIEL: It's exhilarating. When you feel a concussive wave, it's an awesome thing. It fills you with awe. I would love to feel that blast today.
HAMILTON: Daniel and Chris spent two years in the late 1990s firing a rocket launcher called the Shoulder-Launched Multipurpose Assault Weapon or SMAW. They were a team. Chris loaded the rockets. Daniel pulled the trigger. And together, they fired hundreds of rounds in training exercises around the world. Chris points to a photo in a scrapbook.
FERRARI: That's me and Daniel at the base of Mount Fuji posing for a picture with our SMAW rocket launchers.
HAMILTON: The SMAW is one of several modern weapons light enough for one person to carry but powerful enough to blow up a tank. These weapons produce an explosion in the barrel that's as powerful as a small bomb. So Daniel and Chris had their brains rattled every time they fired the SMAW. And they fired it a lot.
DANIEL: Chris and I were incredibly good shots.
FERRARI: We never missed (laughter). We were always selected by our sergeant and our leaders to do the firing because they wanted to see the explosion. You know, they wanted to see the target get hit.
HAMILTON: But as the two men fired the SMAW again and again, some of the thrill began to fade. Chris says every shot was like taking a punch.
FERRARI: It felt like the world was caving in on you. Like, the pressure just was, like - and the heat and the debris and the dirt and the things that would, like, kick up around you. And then it was over with.
HAMILTON: The military limits the number of times troops can fire a heavy weapon in a single day. But the limits are based on concern about hearing loss, not brain damage. And Daniel says they weren't taken very seriously.
DANIEL: And I remember they were saying like, you're only allowed to shoot three of these things a day because it's, like, really bad for you. And I just remember someone mentioning three. And then, like, I would shoot three, and then you would shoot three. So...
DANIEL: ...That's - we're around six. And then the guys 10 feet from us would shoot six. And then the other team would shoot six.
HAMILTON: Chris says he had a lot of headaches and sometimes couldn't think straight after a day on the range.
FERRARI: You feel odd. And you feel out of place. And you feel exhausted and tired. But, you know, you're a Marine. And you learn to, you know, put it away.
HAMILTON: Until you can't. For Daniel, that happened during a joint training exercise in Malaysia. Chris says their platoon was still setting up.
FERRARI: Then all of a sudden, out of nowhere, boom (ph). Nobody was ready for it.
HAMILTON: Malaysian troops just a few feet away had fired an antitank weapon called the AT4. The blast wave hit Daniel like a fist.
DANIEL: I was, like, absolutely dizzy. I was absolutely disjointed. I felt nauseous. Like, I really felt like I needed to throw up.
HAMILTON: So he told his sergeant.
DANIEL: And it was just, shut your face. Like, are you complaining? Like, why is everyone else OK and you're not?
HAMILTON: That was 20 years ago. Back then, the military pretty much assumed your brain was fine unless there was some external sign of injury. Tracie Lattimore, who directs the Army's traumatic brain injury program, says no one really understood how a blast wave could affect the brain.
TRACIE LATTIMORE: The science wasn't up to speed. It just didn't exist.
HAMILTON: But Lattimore says since 2007, the Department of Defense has spent about a billion dollars studying traumatic brain injuries, including those caused by blast exposure. At first, the research focused on bomb blasts. But now, Lattimore says, it includes the effects of blasts from weapons like the ones Chris and Daniel shot.
LATTIMORE: If you talk to us in a year from now, I think we're going to have exponential growth in our knowledge coming out of these current studies and our future studies.
HAMILTON: Eventually, that could help the hundreds of thousands of veterans who fired these weapons in the past couple of decades. But right now, people like Daniel and Chris have no way to know whether firing heavy weapons could have affected their brains. Chris says all those blasts might be the reason he ended up in a military hospital for two weeks. It happened after a weeklong training exercise in the desert near Twentynine Palms, Calif.
(SOUNDBITE OF GUNFIRE)
HAMILTON: There were thousands of troops, and Daniel and Chris fired lots and lots of rockets. They also set off explosives. Several days after the exercise ended, Daniel noticed Chris was awake in the middle of the night.
DANIEL: He just got up and started walking out of the room in his stinking underwear. And I was like, hey, Chris, what's going on? And I was, like, looking at him. And he's just kind of looking through me.
FERRARI: I don't remember it. But I know that they put me in the hospital, and they give me spinal taps. And they thought I had...
DANIEL: Spinal meningitis.
FERRARI: ...Spinal meningitis or something.
DANIEL: Which makes no sense.
FERRARI: We - yeah. And we never knew what happened.
HAMILTON: The doctors thought something was wrong with Chris' nervous system, but they never suspected the culprit might be repeated blasts from the weapon he fired. Chris' military career ended when his platoon left on a bus one morning and he didn't get on it. It's been nearly two decades since the two men fired the SMAW. They both settled in Northern California, which is where they grew up. And they both have symptoms that could be from a brain injury or something else. Chris says he has lots of questions.
FERRARI: Why does this hurt on my body, or why do I feel lost, or why can't I concentrate on stuff as long? Or like, my - these fingers - you know, for the last four or five months, it just - there's no feeling no more.
HAMILTON: Chris also has trouble controlling his emotions now. And Daniel says at least one part of his brain just doesn't work as well as it used to.
DANIEL: Memory. I used to be photographic. Now I'm just having simple - you know, just at work, stuff I do all the time I'm, like, forgetful. I'm, you know, 40 (laughter). That's - I don't know, man. Maybe I'm getting old.
HAMILTON: Chris and Daniel also have problems with balance and spatial orientation, common symptoms of damage to the brain's vestibular system. What makes their symptoms so puzzling is that they were never blown up by an IED. They were never injured in combat. So both men think maybe it was all those rockets.
FERRARI: (Unintelligible) Really the only thing that could have been a factor. I mean, it's the only thing really, you know, I had gone through.
DANIEL: I truly don't know if it's the case for you, Chris. I just know that it's the only thing that makes sense to me now. So to be honest, I'm looking for answers.
HAMILTON: And so is the U.S. military. Jon Hamilton, NPR News.
(SOUNDBITE OF THEO CROKER'S "THIS COULD BE (FOR THE TRAVELLING SOUL)")
SHAPIRO: Tomorrow, how the VA's health care system is responding to veterans like Daniel and Chris.
(SOUNDBITE OF THEO CROKER'S "THIS COULD BE (FOR THE TRAVELLING SOUL)")
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