2007-01-29 04:41:28 · 5 answers · asked by Stratomanssy 5 in Science & Mathematics ➔ Biology
Your breathing has slowed down, but your body has not, and your brain believes (correctly) that it is not getting enough oxygen to pump blood around your body.
Therefore the brain initiates a request to yawn, bringing in more oxygen. This is why you usually yawn at night, when your breathing slows down.
Why do you yawn when someone else does? Merely an instinctive reaction between your eyes and your brain.
2007-01-29 04:47:35 · answer #1 · answered by Peach S 1 · 1⤊ 0⤋
I will tell this much to the autonomic nervous response system known as a 'yawn'. We will only do it in an environment where we feel comfortable. If you feel threatened at all you will not yawn no matter how tired you are. It is also contagious with a simulated response generated within 11 to 43 seconds.
2007-01-29 12:48:38 · answer #2 · answered by photogbob2003 2 · 0⤊ 0⤋
That extra burst of 02 will help wake your brain.
2007-01-29 12:50:00 · answer #3 · answered by michelle 5 · 0⤊ 0⤋
u breath deeply to get mor oxygen to ur brain..
happens when ur tired.. or in a stuffy room..
Xx alisha xX
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2007-01-29 12:46:53 · answer #4 · answered by ..::aLi$hA::.. 2 · 0⤊ 1⤋
I read that the current theory is that it is because the person wants sex.
2007-01-29 12:47:57 · answer #5 · answered by J C 5 · 0⤊ 1⤋