After a head trauma, there may be multiple severe intraparenchymal hematomas.

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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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On the other hand, it is absolutely true that head trauma -- when severe -- can completely change a person's ability to think, feel and accurately perceive reality.

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Dr. Emory Petrack, director of the pediatric emergency department at Fairview Hospital in Cleveland, Ohio, says when it's a "truly critical emergency, " get to the nearest hospital. (Truly critical emergencies include severe pain, trauma with multiple injuries, and difficulty breathing).

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