KELLY MCEVERS, HOST:
Football has been getting a lot of criticism in recent years as information comes out about the long-term toll of head trauma. Today there's more tough news. Scientists now have what they call solid evidence that repeated hits to the head cause the degenerative brain disease CTE even if there's no concussion involved. We'll have more from NPR's Tom Goldman.
TOM GOLDMAN, BYLINE: In the evolving science of head trauma, concussions have been the thing. From battlefields around the world to football fields in the U.S., we've heard about the dangers of when the brain rattles around inside the skull. We've heard about the possible link between concussion and the degenerative brain disease chronic traumatic encephalopathy. A number of former NFL stars have developed CTE, which can cause cognitive problems and dementia and lead to suicide. And in 2015, the injury even became part of popular culture.
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WILL SMITH: (As Dr. Bennet Omalu) A human being will get concussed at 60 G's. A common head-to-head contact on a football field - 100 G's.
GOLDMAN: This is actor Will Smith in the movie "Concussion."
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SMITH: (As Dr. Bennet Omalu) God did not intend for us to play football.
GOLDMAN: But now a team of researchers says all the focus on concussions may be missing the mark. Boston University professor Lee Goldstein was the lead investigator on a study released today in the journal Brain. The research found the real culprit when it comes to CTE isn't concussion with it's often recognizable symptoms that include loss of consciousness, dizziness, confusion. But rather, it's the more common and less obvious hits to the head.
LEE GOLDSTEIN: Although we have had an inkling that the subconcussive hits may be associated with CTE, we now have solid scientific evidence that that is so.
GOLDMAN: The study was seven years in the making. Researchers examined the brains of young adults and did head impact experiments on laboratory mice. The results, says Lee Goldstein, are concerning.
GOLDSTEIN: We're really worried about the many more people who are getting hit and getting hurt. Their brain is hurt.
GOLDMAN: But he says they're not getting help because with a focus on concussion, their less-obvious head injuries are overlooked.
GOLDSTEIN: It's a silent injury.
GOLDMAN: Chris Nowinski of the Concussion Legacy Foundation translates Goldstein's concern to the football field.
CHRIS NOWINSKI: We see the hard hits it's all the time. Then a guy pops up and smiles and points to the first down. And suddenly you go, OK, that hit was fine. And what this study says is, no, that hit probably wasn't fine, but that poor guy can't feel the damage that's happening to his brain right now.
GOLDMAN: Nowinski and Goldstein are hoping the study results prompt policy changes. In fact, today the two men and some former NFL stars launched a campaign calling for kids to hold off playing tackle football until high school. That's obviously not a popular idea with youth football organizations like Pop Warner.
Dr. Julian Bailes is a noted expert on head and brain trauma. He's also a medical adviser to Pop Warner. Bailes coauthored a paper in 2013 about the effects of subconcussive head hits, and he disagrees with the idea of holding kids out of tackle football until high school. It's there, he says, that the game gets more dangerous since kids are bigger, faster and have more violent collisions.
JULIAN BAILES: The question is, where do you draw the line? This study doesn't answer that. There's been no study to answer that question. And again, it's not just football. It's other sports that have the risk for head contact, including ice hockey, lacrosse, soccer and others.
GOLDMAN: But today the focus is on football, where the risk is greatest. In response to the study, the NFL and its players union sent statements vowing to keep working to make their game as safe as possible. Tom Goldman, NPR News.
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