Yawning cleans the brain’s protection

Human According to most people, yawning means that the yawner is tired or bored.

In studies, yawning has also been linked to the fact that it might be possible to regulate the temperature of the brain and temporarily raise the state of alertness.

Many athletes, for example, “breathe oxygen into their body” before a fast performance.

All vertebrates yawn. Because it is also a contagious social phenomenon, it can communicate empathy to others, perhaps to the whole herd.

For a yawn perhaps a new explanation has now been found. Yawning can affect the flow of the fluid that protects the brain.

There is a current in the brain cerebrospinal fluid. It is a clear liquid that protects the human brain and spinal cord. Fluid is constantly forming in the vascular plexuses of the cerebral ventricles.

Cerebrospinal fluid carries nutrients to the central nervous system. It also removes so-called waste products from the brain of the glymphatic theory by.

Yawning may keep the central nervous system in order with the help of cerebrospinal fluid.

Australian Researchers at the University of New South Wales first asked healthy subjects to yawn. There were 22 of them, half men and half women.

Magnetic resonance imaging can be used to sensitively describe and measure the body’s currents. They scanned the yawner’s head and neck with magnetic resonance imaging.

The subject also had to gasp for oxygen in other ways. He had to breathe normally, take a deep breath and stifle the yawn himself.

“We didn’t expect this.”

Break it down and deep breathing are physically the same. So the researchers expected that they would look very similar in the magnetic images as well.

However, the pictures revealed a key difference. Yawning moved cerebrospinal fluid away from the brain. Deep breathing didn’t do it.

“Yawning changed the movement of the cerebrospinal fluid in the opposite direction compared to when the subject took a deep breath,” says the neuroscientist Adam Martinac for New Scientist magazine.

Martinac is a neuroscientist at the Australian Neuroscience Research Centre.

“We didn’t expect this,” he says.

The researchers do not yet know how much cerebrospinal fluid was transferred out of the brain, nor did they check how it was transferred. And what is the significance of the observation in the end.

The muscles of the neck and tongue may have their own role here.

From deep breathing and yawning also revealed something in common. Both increased blood flow away from the brain. It was replaced by more oxygenated blood.

The subjects seemed to have their own ways of yawning. It suggests that everyone’s own nervous system controls yawning and its rhythm.

The differences suggest that yawning patterns are not learned. They are perhaps an innate and neurological part of the individual, the researchers reasoned.

Researchers don’t want to forget what other meanings yawning can have.

It can affect the body’s thermoregulation. Since yawning is contagious, it can also mean a lot socially or as a member of a pack, he says online service Science Alert.

The research has not yet been peer-reviewed. It has been published in the bioRxiv pre-publication service.