Why are yawning contagious?

Although there is no scientific consensus on why we're gagging, one theory is that when humans are tired, we stop breathing deeply, causing a accumulation of carbon dioxide in the body.

AT Douglas Parham, scientist and badociate professor in the Department of Communication Sciences and Disorders at Wichita State University, a yawn could a particular type of breathing It quickly builds up oxygen while evacuating carbon dioxide, even more than deep breathing.

Excess carbon dioxide and other chemical changes, such as an oxygen drop or an increase in a compound called adenosine, could also serve as "gaping gates" . These chemicals send a signal that causes a yawn. By yawning, we compress the facial muscles, bringing blood enriched with oxygen to the brain.

Other theories claim that the yawn is aimed at cool the brain or stretch the internal organs like tissues and lungs, which helps the body to animate. "Despite being a fundamental part of our lives, information about yawning is scarce," he said. Thomas Scammell, neurologist at Harvard Medical School who studies sleep.

This primitive reflex in many animals comes from the brainstem. As humans resemble other mammals (as well as birds and reptiles), it makes sense that most animals yawn. In fact, birds, reptiles, mammals and some sharks can yawn, and animals with larger brains tend to yawn longer.

Dogs are actually infected by humans, and not by other dogs, suggesting that it may be something that they detected only after we started raising them. for that they are more human.

Why are they contagious?

Although yawning remains mysterious, the contagion factor is not. According to a study by the University of Maryland After seeing someone yawn, the probability of doing so increases six times.

For experts, it could be a phenomenon called social reflex, a behavior related to mirror neurons in the brain, where the organisms mimic the actions of others. Other behaviors fall into this category, such as scratching, crossing his legs and laughing.

It is common for social animals, such as humans, to copy themselves to adapt to behaviors, especially when this behavior can be useful for their survival. That is why some research is aimed at determining whether contagious yawning is related to empathy or our ability to understand and share what others feel.

"Empathy can be defined by the ability to understand, share and be affected by the states or emotions of others. So, if seeing someone yawn makes you yawn in response, this action could be placed in an empathy category, "he explained. Andrew C. Gallup, Assistant Professor of Psychology at the SUNY Polytechnic Institute in Utica, New York. Some studies seek to determine whether more empathic people and animals are more likely to yawn. But Gallup, who has been researching this habit for more than 10 years, says more studies are needed to be safe.

It is possible that a yawn (a great inspiration and a stretching of the eardrums, followed by a large expiration) serves to Cool the brain or other parts of your body. It could also have something to do with the regulating the amount of oxygen in the blood. It could even be a reflex that serves to keep the body alert when you are tired or distracted.

"There are a number of other contagious behaviors, such as laughing and itching," he said. Gallup. "Like yawning, these responses can be reliably activated by asking participants to watch videos of other people who perform them."