What is the reason for frequent yawning

summary

If you are sleepy, you will often yawn, even if you are too tired. Even if you just fall asleep at noon, you will yawn. Even if you go to bed early at night, you may still have this situation the next morning. It seems that it is difficult for us to control. Why do people yawn? The simplest understanding is that yawning is a normal physiological phenomenon, which can protect the human body's function and brain cells from hypoxia What is the reason for this?

What is the reason for frequent yawning

Reason 1: the reason for yawning is physiologically thought to be caused by hypoxia. It is said that when the oxygen concentration in the lung is detected to be lower by the tissues around the lung, people will yawn to breathe in more air. However, the latest research shows that the lung does not necessarily detect the lack of oxygen. Through ultrasonic scanning, we can see the image of the fetus yawning in the mother's stomach, but the lung of the fetus in the womb can not breathe. At the same time, experiments have proved that people yawn no more in the environment with more carbon dioxide than in the normal environment.

Reason 2: it is also said that yawning is caused by boredom. If people are tired of something, they will yawn and express their indifference with body language. But the activity of the paraventricular nucleus of the hypothalamus, known as the brain's "yawning center", is often associated with the most interesting things. So the idea that "yawning comes from people's fatigue and boredom" may be wrong.

Reason 3: according to evolutionary theory, yawning is handed down from primitive ancestors to show teeth and warn others. The snake crouching in the grass and motionless often yawns before moving; the hippo in the water yawns first and then comes out of the water. In view of the fact that mankind has entered a civilized society, it is out of date to yawn to warn others. If this is the case, human yawning is most likely an evolutionary relic that has lost its meaning of existence.

matters needing attention

When people are about to enter the intense work, they often yawn. This may be that the human body increases more oxygen in the blood with the help of deep inspiration, and improves the activity of the brain. All in all, yawning is an instinctive reaction of human body, which is not controlled by human will, just like heartbeat and breathing. It has a good protective effect on protecting brain cells, increasing the oxygen supply of brain cells and improving the stress ability of human body.