The NFL wants to use the same sensors, though altered slightly, in football helmets to track the severity of blows to the head, so players may be taken out of games before severe brain trauma namely concussions occurs or escalates.

FORBES: NFL to Follow Army's Lead on Helmet Sensors in Attempt to Prevent Head Injury

In a 1999 article in the peer-reviewed journal Anesthesiology, Gail A. Van Norman, a professor of anesthesiology at the University of Washington, reported a case in which a 30-year-old patient with severe head trauma began breathing spontaneously after being declared brain dead.

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