why is yawning contagious?

Answer:
There is essentially no chemical or gas release in a yawn that would cause another person to yawn. And yawning is not side effect of any communicable ailment. Yawning is not really contagious, it is more a somatic effect that causes other people to yawn when they see or hear someone yawning. Yawning is how the brain gets a lot of oxygen very quickly when it is low. Which is why you yawn when you are tired but are either unable to sleep, or trying to stay awake. The brain registers either situation as the same, and b/c it's functioning as though you are supposed to be awake, if it doesn't have enough oxygen, it recognizes the potential for fatality if it doesn't get a lot of it very quickly. So you yawn, because the brain signals for you to do so, so that you can stay awake.

---

Yes but I don't know why.

---

Nobody knows, it's the great unanswered question of our time. My guess it's an empathic trigger in the brain.

---

i dont know y yawning is contagious but i do know u yawn because u dont have enough oxygen in ur blood

---

well, i think when you see someone yawning that make you feel and remember or realize whatever and the mechanism in the brain order you to yawning. It's like you not feel hungry but, if you see some food can make you feel hungry. I think.

---

It's because of the "power of suggestion". It's like when you see someone eating ice cream, you also want ice cream and crave it. Not that you crave yawning, but the mere suggestion makes you do it. Try this... take a normal glass of water and pass it around a room asking how many people smell ammonia in the glass. About 80% will smell ammonia even though there is none in the glass. It's the "power of suggestion".

---

I saw on National Geographic that yawning they think was some sort of primitive universal sign that cavemen, and early humans used. For some reason we havent evolved out of it. They dont know what exactly its for, but that was thier take on it.xxx

---

It is purely psychological.

---

actually wen we yawn intake of oxygen happens i think u kno y we yawn only wen our brain cells becomes fatigue. so microbes present in the surounding air wil enter inside our lungs and might cause asthma n other respiratory problems but usually it doesnt happen bcoz of our body immune system

---

I think this is a very very good question . I have wondering fro years and years for this and I never got the answer . But however , If I see a good and best answer chosen by the asker , Hope I will get a good answer . I have been thinking of asking a question on google answers as well as ByeDR . But , However I think I will get a good answer .

---

Yawning in one removes the inhibition in others

---

yawning is due to the excessive production of carbon -di-oxide in our body so when v yawn co2 is released in huge amount hence it pasess to others hence its contagious

---

because you are watching the other person yawn

---

I just clicked to answer your question.When I began to type, I noiced that I was finishng my yawning.I wondered how mere reading of the word causes yawning.

---

cos while doing so u r spreading so many microorganisms..but not so sure!

---