A Yawn is More Complicated – and Important to Mental Focus – Than We Think

Yawning – it seems so simple, right? A stretch of the jaw, a quick intake of air, and that’s it. But what if this ordinary act holds extraordinary benefits for your brain? New research reveals that yawning is far from trivial – it’s a powerful mechanism that keeps your brain cool, alert, and functioning at its best. Discover how each yawn is like a mini air conditioner for your mind and why you might yawn more around your loved ones or even your dog!

Key Takeaways

• Yawning lowers brain temperature by increasing blood flow and allowing cooler air to circulate through the sinuses.
• Yawning is more contagious among close friends and family and is influenced by brain size and social bonds.
• The act of yawning boosts cerebrospinal fluid circulation, clearing away sleep-inducing chemicals like adenosine.

Why Yawning Is Your Brain’s Secret Weapon for Staying Sharp

For the longest time, the act of yawning puzzled medical researchers. Yawning seems commonplace and insignificant – you feel tired, you yawn. You see somebody else yawn, you yawn. You get bored, you yawn.

The problem researchers faced was how to tie these circumstances together and figure out a definitive biological purpose for yawning. When they did, they discovered that every yawn helps the brain function better and remain more alert. Here’s the surprising research.

Researchers in Switzerland found that yawning forms part of the brain’s “thermoregulatory” system. It’s controlled by a part of the brain called the hypothalamus, which regulates body temperature.¹ So, say researchers, an essential function of yawning is to lower the temperature of brain tissue.

Your Brain’s Air Conditioner

One of the first clues about the brain-cooling function of yawns was the fact that in spring, as temperatures warm, people tend to yawn more. But then, as the body adjusts to the warmer temperatures, our yawning rate goes down.

Another clue is the discovery that brain tissue is consistently warmer than the blood flowing through the body. And when you yawn, as the muscles of the jaw open your mouth and contract, extra amounts of cooling blood course through your head – like the coolant that flows through a car engine to keep it from over-heating.

Plus, your sinuses also flex during a yawn. That allows for more cooling through the thin walls of the sinus as extra, cooler air enters your head.² So, in the same way that a cool breeze blowing across your face when you’re tired can help you stay more awake when you’re fatigued, the cooling action of a yawn, through a similar effect, can also boost your alertness.

Along with its cooling action, researchers in Switzerland say that a yawn and the muscular contractions that go with it also boost circulation of the cerebrospinal fluid. That increased flow helps to clear the brain of natural chemicals such as adenosine (a neurotransmitter) and prostaglandin D₂ (a hormone), that are linked to sleepiness.³

Catching a Case of the Yawns

As you’ve probably noticed, the act of yawning is contagious. If you see somebody else yawn, you’re more likely to yawn. However, research in Italy demonstrates that not all yawns are equally contagious. Perhaps not surprisingly, the yawns of your closest family and friends are more catching than the yawns of strangers.⁴

Along with that, men’s yawns elicit the yawns of other people more than female yawns, while women are generally more likely to start yawning when other people yawn than men are.

Researchers have also found that the bigger your brain, the longer your yawns. More brain tissue means you have more brain cells that need cooling – kind of like the way a large limo or SUV needs a bigger cooling system than a tiny Smartcar.

Interestingly, this also holds true for animals. A study on dogs shows that dogs with bigger heads and brains yawn for longer periods of time than small dogs with smaller heads.

One final yawning tip: If you’re in an important meeting and you’re trying to fend off the impolite urge to yawn, make sure to keep breathing through your nose. Air taken in through your nostrils and sinuses will cool your brain more than air that enters through your mouth and may make it easier to resist a yawn.⁶

Summary

Yawning is more than a sign of fatigue or boredom – it’s a biological process that plays a crucial role in brain health. Recent research shows that yawning helps regulate brain temperature and improves alertness by increasing blood flow and cerebrospinal fluid circulation. Yawning is also contagious, with close relationships and even brain size influencing the frequency and duration of yawns. From boosting cognitive function to cooling the brain, this fascinating phenomenon offers surprising insights into how our bodies stay sharp and ready for action.

Frequently Asked Questions

Why do we yawn?

Yawning helps cool the brain, improves circulation, and clears away sleep-inducing chemicals.

Is yawning really contagious?

Yes, yawning is more contagious among close friends and family and less so with strangers.

Does yawning improve brain function?

Yes, yawning boosts cerebrospinal fluid circulation and helps remove chemicals that cause sleepiness.

Why do we yawn when we see others yawn?

Contagious yawning may be linked to empathy and social bonding.

Does the size of the brain affect yawning?

Yes, larger brains require more cooling, leading to longer yawns.