With a concussion, there is no obvious injury - no blood, no swelling, no arm at an awkward angle.
Coaches and athletic trainers have to look for subtle signs from an athlete, such as a shake of the head, a vacant expression or a long pause before a football player lines up for the next play.
Until the past few years, a student athlete in Mesquite might have gone back into the game after a quick assessment. But that's changing as officials realize how common concussions are and how profound their effects can be over time.
"If a kid suffers a concussion in Mesquite, they are going to miss a minimum of two weeks," said Bucky Taylor, Mesquite High School's head athletic trainer.
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