Why don't we yawn in our sleep?

Question

We can't stop yawning before we finally go to sleep and then quit. Why?

Answer 1

How do you know you're not yawning while sleeping?

The real reason for a yawn is not yet confirmed. Theory implies we yawn because our bodies are trying to get rid of extra carbon dioxide and to take in more oxygen. This may make some sense. According to this theory, when people are bored or tired, they breathe more slowly. As breathing slows down, less oxygen makes it to the lungs. As carbon dioxide builds up in the blood, a message to the brain results in signals back to the lungs saying, "Take a deep breath," and a yawn is produced.

Therefore, this can partake while sleeping as well. Unless you have someone watching you during your entire sleep duration, you don't know if you yawn or not.

Answer 2

Because we are sleeping & that's what the yawning was telling us we needed. Also, quick fact: yawning doesn't always necessarily indicate tiredness & the need to sleep. Sometimes we yawn to get more oxygen to the brain because there may be a small lack of it that our brain is craving.

Answer 3

yawning doesn't mean we are tired it means we aren't getting enough oxygen to our brains. Our bodies respond to this by yawning. How are you sure that we don't do it in our sleep?

Answer 4

you yawn from oxygen deficiency, not to go to sleep. you yawn to stay awake. you need less oxygen due to decreased heartrate and other body processes when you're asleep so there's no need to yawn.

Answer 5

you yawn to achieve the goal of "sleep", while sleeping=no need...

Answer 6

if we are asleep, how do you know we we 'e not yawning...

Answer 7

who says you don't?