正在确认阅读权限…
Why Do We Yawn?
我们为什么会打哈欠？
-
Yawning is a deep breath that pulls air into the lungs.打哈欠是一种将空气深深吸入肺部的呼吸。
-
It often happens when we feel tired or bored.我们感到疲倦或无聊时常常会打哈欠。
-
One idea is that yawning cools down the brain.一种观点认为，打哈欠能给大脑降温。
-
Taking in cool air helps keep the brain at the right temperature.吸入凉爽空气有助于维持大脑的适宜温度。
-
Yawning also stretches jaw muscles and increases heart rate.打哈欠还能拉伸下颌肌肉并加快心率。
-
It may help us stay awake and focused for short time.它可能帮助我们在短时间内保持清醒和专注。
-
People and some animals yawn even before birth.人类及某些动物在出生前就会打哈欠。
-
Yawning is contagious — seeing it makes others yawn too.打哈欠具有传染性——看到别人打哈欠，自己也会跟着打。