Yawning May Be Your Brain's Way Of Cooling Down
Gallup: You often misinterpret it as a sign of boredom or a sign of sleepiness. And while it may be indicative of those things, it is certainly not always the case.
Ditmire: Instead, he believes it’s our body’s way of making our brain more alert.
Gallup: I think it could be instead thought of as a sign that someone is attempting to pay more attention to what is going on.
Ditmire: To do so, the brain needs to be at optimum temperature, which Gallup says is close to a normal body temperature of 98.6.
Gallup: Brains, much like computers, operate most efficiently when they are running at a effective temperature. So while many computers have internal cooling systems such as fans, our brains also have internal circulatory cooling systems and yawning appears to be one mechanism which activates those systems and provides a cooling component.
Ditmire: Gallup wondered if outside temperature or sunlight triggered the cooling system. So he conducted two independent studies during both winter and summer, in Arizona and Austria.
Gallup: What really appeared be driving this effect—and we can demonstrate this statistically after controlling other variables—was the ambient temperature. So the most yawning in Tucson Arizona occurred during the winter, when the ambient temperate is actually very close to room temperate. In Vienna, however, the most frequent yawning occurred during the summertime. And again, those ambient temperatures were very closely aligned with what we would consider room temperature, between 68-70 degree Fahrenheit.
Ditmire: Which Gallup says proves that our brain regulates its cooling system on its own.
Gallup: I’ve argued that the deep inhalation of ambient air temperature accompanied by the stretching of the jaw acts to alter the first two variables, the rate of the blood flow and the temperature of the blood.