It's game day at Indiana University, but before the first play is called, signals are checked - not from the players, but from the helmets they wear.
The Hoosiers hit the field wearing a new system that can detect concussions - even before a player reports any symptoms.
"It alerts us, it's an eye in the sky, its a backup to our own eyes watching the players practice and play," Brian Lund told CBS News contributor Dr. Sanjay Gupta.
Here's how it works: Every helmet is equipped with sensors that monitor how much force - known as G-Force - a player's head receives during a game. The helmet transmits the data to a computer system; if a player receives a blow to the head above a certain threshold, usually 98 G's, the computer pages the medical staff and tells them which player was hit - and how hard - so they can check him out.
That's important because the symptoms of concussion are often subtle and are usually ignored by players.
The hope is that a player can be removed from a game without risking further damage. The medical staff also keeps a record of how many impacts a player's head receives during a season.
"We get it all right on the system," Lund said.
Now there are lots of numbers to look at, lots of graphs to analyze, all that information coming from this helmet. But what really matters is the safety of the players, and the effect of this violent game.
The highest recorded hit in Indiana football history is from Andrew Means from a game last year.
"He catches the ball boom, boom. It seems like a big hit," Lund said.
"I barely remember me even grabbing the ball and catching it," Means said. "Anything after that is just gone."
Means was not knocked out, but he did suffer a concussion. Data from his helmet revealed a violent sequence of events occurring in just a split second.
As Means was hit by the opposing player, the impact was high, but just below the concussion threshold. When he hit the ground however, his helmet recorded a second, huge hit - 155 Gs.
"So what looked like one impact is actually two impacts," Lund said.
Means was sidelined for several weeks, but is back and better than ever this year.
How many times has he watched the tape?
"I've watched it multiple times, every time it gets better, too," he said.
The helmets have also shown that it's not just how hard you get hit, it's where you get hit.
On another play, number 20 suffers a concussion and is knocked unconscious from a hit on the side of his head that registered only 65 Gs.
So what you've already learned just from having this system that is if you take a hit to one side of the head, versus the top, these are much worse.
"They can be much worse and at a lower threshold," Lund said.
Sixty-five Gs knocked that guy out cold, whereas 155 Gs didn't knock the other guy out.
"That's correct," Lund said.
Indiana is one of eight college teams using this system this fall, at a cost of about $50,000 per system. The hope is there will be fewer concussions, by keeping an electronic eye on all the hard knocks.
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