Head trauma and sports—most notably football but also hockey, soccer and boxing—have been the focus of plenty of media coverage. Recent studies have shown an overwhelming majority of deceased football player’s brains contained evidence of chronic traumatic encephalopathy, or CTE.

But a recent report from CBS’s 60 Minutes focused on soldiers returning home from Iraq and Afghanistan. Ann McKee, MD, with the VA-Boston University-Concussion Legacy Foundation Brain Bank, spoke of the difficulties faced by the 300,000 soldiers who have suffered brain injuries since Sept. 11, 2001.

“It's not a new injury. But what's been really stumping us, as physicians, is it's not easily detectable, right?” said McKee, a key figure in initial stories of CTE in football players. “You've got a lot of psychiatric symptoms—and you can't see it very well on images of the brain, and so it didn't occur to us. I think that's been the gap, really, that this has been what everyone calls an invisible injury.”

Lee Goldstein MD, PhD, is building on McKee’s research by testing mice to see how blast impacts can change brain function.

“What we see after these blast exposures, the animals actually look fine, which is shocking to us,” Goldstein said. “So they come out of what is a near lethal blast exposure, just like our military service men and women do, and they appear to be fine. But what we know is that that brain is not the same after that exposure as it was microseconds before. And if there is a subsequent exposure, that change will be accelerated. And ultimately, this triggers a neurodegenerative disease. And, in fact, we can see that really after even one of these exposures.”

To see the full segment, along with a transcript, here.