Yawning May Cool the Brain When Needed, University of Maryland Study
11/28/2011 7:13:07 AM
Yawning helps keep the brain cool, and the sinuses play a role in that process by acting as bellows, a new report suggests. Yawning isn't triggered because you're bored, tired or need oxygen. Rather, yawning helps regulate the brain's temperature, according to Gary Hack, of the University of Maryland School of Dentistry, and Andrew Gallup, of Princeton University.