Why Do We Yawn?

Why do we yawn? If you think the answer is BOR-ing, then maybe your brain's just overheated. Let Hank explain the new thinking behind why we ... hold on ... *yawn*. Excuse me.

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[Borednesss]

My old biology professor used to tell us yawning was a way to make yourself more focused and alert, and he actually appreciated it when students yawned during his lectures because to him it meant you were interested in what was going on and were trying to focus on him. Or maybe he just said that so we were reminded to stay focused after we yawned, lol.

[rickseiden]

Here's a thought.  You yawn when your brain gets hot from consuming all that energy, right?  So that means you're thinking about something really hard.  Next time you yawn when your boss/teacher is talking to you, tell them it's not a sign of boredom, but a sign of paying attention, and that you mean it as a compliment.

[Stray]

You cannot believe how much I yawned while watching this. XD

[cheatingthesystem]

Years from now the 'Laptop' and 'reddit' references will date this video super hard hahah

[courtneycallahan]

Yawns are contagious.. I literally couldn't stop yawning through this entire video.  Thanks for keeping me cool, Hank!

[flabbergast_se]

Couldn't stop yawning watching this...

[mahboi]

FOR THOSE WHO WANT TO KNOW WHY YAWNING IS CONTAGIOUS:

There are these handy things in our brains called mirror neurons that, according to study, activate when we see things people are doing that we understand we can do as well.  When people yawn, our mirror neurons go at it, saying "hey I can do that too" and yawn along with them.  This is also why humans tend to feel empathy, such as feeling sad for people when people feel sad, etc.

Hope this helps.

[AndreasFilms]

I must've yawned about 10 times while watching this video

[evangelion]

How many people yawned while watching this I wonder?

[TheOriginalPoon]

One of the biggest questions is why yawning is so hyper contiguous, that even reading or talking about it makes one yawn.

That is more important to me than the why

[cjpatz]

I notice the moment I yawn I'm momentarily deaf till the yawn is over.

[ZoggFromBetelgeuse]

How many of you Earthlings managed to watch the whole video without yawning once ?

[RachelandJun]

So is that why I yawn so much right after a run?!
-Rachel

[TheSHNGAM]

Conclusion: playing hours of video games is great exercise.

[saulvelazquez]

Then why do my eyes water after I yawn?

[KingKitony]

I have a followup question, why did I yawn like ten times during this video when I had not been yawning at all before it? In other words, why do I yawn when someone yawns or even mentions it?

[RCat]

Someone should make a gif showing hank making all of his funny expressions as he speaks and moves his hands about

[Nomaken]

Holy crap.  That SO explains why i yawn a lot more when i'm really confused by something i'm learning and i'm really frustrated trying to concentrate on it and figure it.

[mjdjoy]

But that doesn't explain why yawns are contagious D: 

[dennisdavis]

i yawned 6 times while watching this video...and once again while i was typing the word 'yawn'