"Sports Injuries May Cause Lasting Brain Damage"

ROBERT SIEGEL, host:

The starting quarterbacks for Sunday's Super Bowl have something in common - both have suffered repeated concussions on the field. These type of head injuries can lead to severe brain damage, sometimes years or decades later. Scientists are still trying to figure out whether brain problems will affect a lot of NFL players down the road or just a few of them. NPR's Jon Hamilton has our story.

JON HAMILTON: Impacts that violently shake a player's brain are a part of football, a part that helmets can't prevent.

(Soundbite of CBS NFL coverage)

(Soundbite of crowd cheering)

Unidentified Man: A wide hit, ball's out.

(Soundbite of crowd cheering)

Unidentified Man: Recovered by Timmons. Ryan Clark is still down. So, too, is Willis McGahee, and they say, fumble recovery, Pittsburgh.

HAMILTON: That was from the CBS broadcast of a playoff game between the Baltimore Ravens and the Pittsburgh Steelers just a couple of weeks ago. Willis McGahee, the Baltimore player, was knocked unconscious and spent the night in a hospital. He says, he's fine now. But Doctor Ann McKee of Boston University worries about players who take repeated blows to the head. She's examined the brains of seven former NFL players who died of various causes before they reached 50. The most recent was Tom McHale of the Tampa Bay Buccaneers, who died at 45. McKee says, six of the players she examined had the same sort of damage found in some aging boxers. The brain tissue shrivels, and tangles begin to appear.

Dr. ANN MCKEE (Associate Professor, Neurology and Pathology, Boston University): We don't see anything like this in the normal population. This is something significant.

HAMILTON: McKee says, the research on boxers suggests that at least one in five who suffer multiple concussions experience a slow degeneration of their brains later in life.

Dr. MCKEE: You know, once it's triggered, it just keeps on progressing, even though most of the time, the athlete has stopped getting the injuries, they've retired from the sport, but unfortunately, the process continues in the brain as long as they live.

HAMILTON: And it leads to memory problems, depression, incoherent thoughts and eventually, dementia. But McKee says it's hard to use research on boxers to draw conclusions about football players.

Dr. MCKEE: There's so little we know about this, and everything needs to be found out. We need to find out how many hits. Do the hits have to come in close succession? Does it matter how old a person is when they get their injuries? And we think there's probably a genetic susceptibility, but we really just don't know what that is yet.

HAMILTON: McKee hopes to know a lot more after studying at least 100 brains from former football players. That will take years, though, because the studies can only be done on players who have died after agreeing to give their brains to science. Mark Lovell runs the Sports Medicine Concussion Program at the University of Pittsburgh. He also works as a consultant to the NFL. Lovell says, it's not easy to assess the risk from concussions to an individual player.

Dr. MARK LOVELL (Director, Sports Medicine Concussion Program, University of Pittsburgh Medical Center): You can see athletes who've had numerous concussions who seem to be functioning perfectly well. You can see athletes who have had one concussion who aren't functioning.

HAMILTON: Lovell says, it's not even clear how many players actually sustain concussions during the season. Many won't say anything that might get them removed from a game. And medical technology doesn't offer trainers and coaches much help in getting a quick answer.

Dr. LOVELL: The problem is is that the traditional ways of detecting brain injuries, such as CAT scans and MRIs and things like that, are really not at all sensitive to concussion. So, they really don't tell us much, other than the fact that there hasn't been a more serious brain injury, such as bleeding, et cetera, in the brain.

HAMILTON: Lovell says, that may change in the next decade. In the interim, he says, teams appear to be keeping players off the field longer than they used to after a blow to the head. Even so, Ann McKee says, she'll be thinking about head injuries while she watches the Super Bowl on Sunday. Dr. MCKEE: You worry about all the hits. So, you really worry about it, and you know, you wonder what's going to pop up in 10 or 20 years.

HAMILTON: Jon Hamilton, NPR News.