Yawning is usually brushed off as a harmless sign of sleepiness, boredom, or lack of focus. In truth, it plays an important role in regulating brain alertness and oxygen levels. While the occasional ...

From morning stretches to moments of boredom, why do we yawn? And why can't we resist when someone nearby does it too?

New York Yankees second baseman Jazz Chisholm Jr. isn't letting the trolls get to him after being caught on video yawning ...