why do people yawn? and why is it contagous?

Answer 1

A yawn is an involuntary reaction caused by your brain not getting enough oxygen.

No one is sure why seeing someone yawn tends to cause you to yawn.

Answer 2

It's lack of oxygen that I'm sure of, but I have my own theory about why it is supposed to be contagious.

First of all not everyone will yawn when the see someone yawn and it doesn't happen at all times. I think that is because we only yawn if we need extra oxygen, if you don't need it then you won't yawn simply by watching someone else yawn.

If one person in the room starts to yawn, say in a class room, then the other persons in the room is likely to have been in the room for just as long. Sitting still in a room full with people will lower the level of oxygen in your body and in the bodies of the others too, then it's more likely that the yawn will be contagious.
In the buss on the way home in the evening most passengers are equally tired and "out of air" and then the yawn is more likely to spread.

In the middle of the day when people are more active and has filled up on oxygen the yawn is less likely to spread since people have no need to fill up on oxygen.

Answer 3

Actually I believe that there is also another precipitator for yawning, not just the oxygen in the blood thing. I know people who yawn just around specific people, when they are talking. I have asked them if they were bored or tired and they don't know why but certain people regularly trigger their yawning.

My theory is that it is to do with the sound of their voice and its lulling or soothing effect. Still trying to work it out though.

Answer 4

I yawn when I'm bored or tired. the extra intake of oxygen keeps me awake for a little time longer. Anyone around you will do the same thing. I've never yawned when I'm doing something that is fun.

Answer 5

1. Yawning is induced by hypoxia (low oxygen levels in the blood stream).
2. Yawning is a method for communicating to other individuals your physiological state of being tired.

3. Yawning is used to stretch out the lungs to prepare them for use.

As for the larger question of why yawns are catching, nobody really knows. Fact is, we don't know why people yawn, period. But I can tell you my cat can even make me yawn. :-)

Answer 6

Promise...I yawned right after I read your question. So..I gotta think it's "the power" of suggestion. Just like..you might not feel like you gotta p...but the closer you get to the bathroom..the more you gotta..and sometimes almost don't make it there in time. (And before that..you didn't even think you had to go)
EDIT..And I ALWAYS have to yawn whenever I sing...I've done that even when I was a little girl singing at church.

Answer 7

You can MAKE yourself yawn.... try it. Take a deep breath.... now breathe shallow for a while, keeping a good helping of air from circulating out. Within a few moments, you'll yawn. This is a condition which occurs naturally when we are tired. It's both relaxing to our lungs and invigorating to our senses, so when once seen... you are compelled to indulge.

Answer 8

People yawn in order to get more oxygen to the brain. Not everyone will also yawn. Those who do are believed to have more empathy for people.

Answer 9

I actually asked my science teacher, who has a degree in neuro-science, the same question this week. He told me it's actually just the power of suggestion. We see someone yawn and it puts our focus to being tired, or makes us feel like we're tired. Like when you see someone laugh, or cry, it makes you want to do the same.

Needless to say, after I asked the question everyone in the class started yawning.

Answer 10

I think this is one of the great questions. I don't know, but I suspect it's suggestibility and a little bit of the old herd mentality.