Placeholder Image

Subtitles section Play video

  • [Yawn] Oh, sorry. I'm not tired, my brain's just overheated.

  • At least that's what a new study says. Researchers at the University of Vienna found that the

  • amount of yawning we do increases when our brains are hot. (Via ScienceDirect)

  • "Much like a computer, your brain works best at a certain temperature and tries to avoid

  • over-heating. And it turns out, yawning increases your heart rate, blood flow and the use of

  • muscles in your face, which are all essential to cooling the brain." (Via YouTube / AsapSCIENCE

  • )

  • So, why is yawning associated with being tired? Well, exhaustion and sleep deprivation are

  • known to increase overall brain temperature. (Via Flickr / twob / nate2009)

  • But as the Daily Mail points out, researchers found people yawn less when it's hotter than

  • normal body temperature outside, which makes senseyou would be breathing in hot air.

  • Not exactly cooling.

  • The research says people also yawn less at the other extreme. When it's super cold outside

  • like, say, frozenbrain cooling may not be necessary. (Via Walt Disney Studios

  • / "Frozen")

  • Time notes this study builds on research that showed yawns are preceded by sporadic rises

  • in brain temperatures and are followed immediately by decreases in brain temps.

  • We still don't know why yawning is contagious, but the researchers argue it might be an evolutionary

  • trait to improve overall alertness.

  • TED says it's an empathetic response.

  • "In fact, contagious yawning starts occurring when we are about 4 or 5 years old, at the

  • point when children develop the ability to identify other emotions properly."

  • And now I'll be yawning all day.

[Yawn] Oh, sorry. I'm not tired, my brain's just overheated.

Subtitles and vocabulary

Click the word to look it up Click the word to find further inforamtion about it