Utterly Fascinating: The Reason We Yawn

A new study says the reason for yawning is an overheated brain:

"Brains are like computers," Andrew Gallup, a researcher in the Department of Biology at Binghamton University who led the study, told Discovery News. "They operate most efficiently when cool, and physical adaptations have evolved to allow maximum cooling of the brain."

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If air in the atmosphere is cooler than brain and body temperatures, taking it in quickly cools facial blood that, in turn, cools the brain and may even alter blood flow. Prior studies reveal yawning leads to a heightened state of arousal, so a morning yawn may function somewhat like a cup of coffee in providing a jolt of energy.

The new findings also explain why tired individuals often yawn, since both exhaustion and sleep deprivation have been shown to increase deep brain temperatures, again prompting a yawn-driven cool down. Yawning additionally appears to facilitate transitional states of the brain, such as going from sleep to waking periods.


They study says the reason yawning can be contagious among humans is an innate instinct from our more tribal days to stay alert in case of danger.

And as for boredom:

But the new study on yawning changes the popular notion that yawns are mere signs of boredom.

On the contrary, as Gallup said, "yawning more accurately reflects a mechanism that maintains attention, and therefore should be looked at as a compliment!"

I love science.