The Science Behind Yawning
A dog behavioralist once told me that dogs yawn as a calming mechanism. I listened, but waited to observe my own nervous pup before I bought in. But it’s true: any time she’s stressed or in a confrontational scenario, my dog yawns. Maybe it’s time to take (another) cue from our four-legged friends.
Common belief is that yawning helps to increase the oxygen supply. But new research by Psychologist Andrew Gallup of SUNY College at Oneonta now reveals that yawning cools the brain. Cooling the brain functions to improve arousal and mental efficiency.
Brain temperature fluctuates with sleep cycles, cortical arousal, and stress. Yawning subsequently functions to keep the brain temperature balanced and in optimal homeostasis.
How did researchers figure this out? By observing yawning in two different climates during two different seasons. Results showed that in cold Vienna people yawned more in summer than in winter, whereas in hot Arizona people yawned more in winter than in summer. It was not the seasons themselves, nor the amount of daylight hours experienced, but that contagious yawning is constrained to an optimal thermal zone or range of ambient temperatures.
When yawning functions to cool the brain, yawning is not functional when ambient temperatures are as hot as the body, and may not be necessary or may even have harmful consequences when it is freezing outside.
The message? If you’re in a stressful—or hot-but-not-too-hot—situation, make like your dog and just yawn to improve mental efficiency!
Credit: Andrew Gallup