The science of yawning

It's something we do every day, multiple times, and we often "catch" it from other people doing it. Correspondent Faith Salie looks into the physiology of yawning, and why it not only helps our brains, but also is a sign of empathy and, yes, increased alertness.

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[margaretpeabody]

Always thought yawning was about sleepiness or boredom
The idea of brain preparation or an autonomic social response is refreshing.

[channelthefire]

I doubt anyone watched this without yawning

[rubychew]

When I was student teaching the teacher got upset with me for yawning. I told her that this is a normal reflex reaction. She was difficult to deal with.

[coryjohnson]

I yawned like six times during this story.

[MaryJane]

I yawned 10 times while watching this video. Yawning is contagious. I’m glad to learn that it’s not a sign of boredom, but a physical reaction in order to focus, and become alert.

[ParkerPPipe]

My mom took me to the doctor when I was a kid because I would walk around yawning saying I couldn’t catch my breathe. As I got older I realized I did it when I was stressed. Still do it to this day.

[letthedogsout]

My husband was a juvenile diabetic and when his blood sugar was low he would yawn. This was always the first clue for me that I needed to spring into action and get him some emergency glucose

[kawaiiwitchbaby]

I think this story leaves out one of the most common yawning reasons. Anxiety. I've been yawning through my anxiety for over 25+ years. There is a lot of research that says it can be a sign of anxiety. I'm not bored or tired. Just extremely anxious.

[rrfirefly]

The woman falling out of the airplane was not yawning. She was screaming out of fear. (2:54)

[imamused]

Yawning on purpose will stimulate tear flow and can help relieve dry eye. No more eye drops!

[iampiyushsingh]

I literally had a big smile after I heard the real reason behind yawning because I always thought of my hobbies were lies because I used to yawn during doing them and thought I find it boring and I keep telling lies to myself.

This actually makes a lot of sense, because I rarely yawn when I play video games but during studies it increases by lot

[trghudson]

I'm not surprised at the Cornell professor's reaction. I spent a summer attending a Cornell recruitment program before my senior year in high school and found the professors in the classes I took to be stuffy and a bit full of themselves.

[missmlb]

there's yawning that's involuntary...then there is yawning that is outloud and disrespectful and it basically says, "I'm not interested in what you have to say..I'm bored."

[maddiesheffield]

I'm fully in tears from yawning after watching this

[susansuewwilliams]

I have asthma; instead of coughing, during an asthma attack, I yawn; as soon as I take my medication the yawning stops.

[TraumaSurvivorCynthia]

When my dog 🐕 It makes me yawn also!! Lol 😂
#davesandersstepdaughter

[ratso]

I yawned five legitimate yawns during this segment. My brain is FREEZING now.

[CamiloVelandia]

oh boy, do I have a great comeback for my mom now! Great video!

[JoseMorales-lwnt]

Here is where my hope for the positivity of humanity comes into play. I have yet to meet a person who has found a way to weaponize yawns! Trust me, if yawns were live bullets, all humans would be dead by now...

[minervagalvez]

I YAWNED THROUGHOUT THIS ENTIRE VIDEO!!! LOL!!!