What is yawning? – 28/02/2019

By RONI CARYN RABIN

Does yawn have a purpose? I know that means you're sleepy, but Does the body want to accomplish something with yawning?

People yawn when they are tired, but also when they wake up after sleeping all night. We gag when we are bored, but also when we are anxious, hungry or about to start a new activity. Yawning is contagious… we usually start yawning just when someone near us does.

"There are a lot of detonators." People who skydive say that they usually yawn before jumping in. Police officers say they yawn before getting into a difficult situation, Adrian said. Guggisberg, professor of clinical neuroscience at the University of Geneva.

Reading about yawning makes people yawn: Maybe you are yawning now.

However, the physiological goal of yawning remains a mystery. "Until now, the most sincere answer is that we do not know why we are gagging," Guggisberg said. "To date, no physiological effect of yawning has been observed, and for this reason, we speculate. It is possible that yawning has no real physiological effect ".

About thirty years ago, scientists explained yawning as a reaction to oxygen deprivation, through which we could inject a large amount of air into the body to increase the oxygen level. in the blood. However, the hypothesis of oxygenation was ruled out after a series of experiments published in 1987 that disproved it.

One current theory is that yawning is a brain cooling mechanism "This helps to promote a state of alertness or vigilance," said Andrew Gallup, badociate professor of psychology at the Polytechnic Institute of the State University of New York, and who has published studies on the subject.

Yawning is a deep inhalation of air accompanied by a powerful stretching of the jaw, followed by a shorter expiration and a quick closing of the jaw.

"Together, these patterns increase blood flow in the direction of the skull, which can have a series of effects and one of them is brain cooling, "explained Gallup." When our body temperature is high, we feel tired and sleepy, and yawning may be nocturnal be activated to resist the initial feeling of sleep. We therefore yawn at night to remain vigilant or surveillance. "

Sleep activates a pronounced reduction in brain and body temperature, Gallup explained. It is therefore also possible that "we only slap to facilitate the transition from the previous day to lethargy".

One thing is certain: yawning is contagious. The yawn of a person can make a whole group react in reaction. It is believed that the yawning of others influences empathic people more easily; Studies using brain scans have shown that when humans observe other people yawning, areas of the brain involved in social functions are activated. Even dogs yawn when they see their human owners or strangers, and contagious yawning has also been observed in other animals.

The spread of yawning could be aimed at "promoting coordinated surveillance among group members by synchronizing their mental state, so that they can protect themselves by alerting themselves to outside threats more quickly than under other conditions" he suggested. Gallup.

© 2019 the New York Times