Yawning is a reflex behavior in humans and animals and is usually associated with fatigue, with the need to go to sleep or to wake up. However, humans also yawn in other situations, so the process has also become a symbol of boredom, even laziness. Yawning is even associated with cultural conditions; in Western cultures, for example, it is considered unseemly not to hold one’s hand in front of one’s mouth when yawning. Researchers have also been able to prove that even the fetus in the mother’s womb yawns and stretches in the process, which leads to the assumption that boredom is hardly the reason for yawning, but rather that the airways are expanded in this way. However, what yawning actually does biologically has not really been clarified to this day.
What is yawning?
Yawning is a reflex behavior in humans and animals and is usually associated with fatigue, with the need to go to sleep or to wake up. Among the Greek mythological figures, there was Nyx, the goddess of the night, who yawned from the chaos and of whom even Zeus was afraid. This gave rise to the belief that when yawning, the soul would leave the body to ascend to the gods of Olympus. Similar ideas can be found in the writings of the Mayans or in Celtic sagas. In the Middle Ages, people even believed in demons that would enter through the ripped throat to steal the soul. This led people to cover their mouths when yawning, which eventually became a manners. Although yawning, like laughter, occurs reflexively, there can be no question of a reflex, since a stimulus is basically absent. Humans yawn in the most different situations. Why exactly the opening of the mouth takes place, as if one had to inhale and exhale deeply, is still a mystery even for scientists, although several theories exist. The science of yawning is called chasmology, because yawning actually seems to be an extremely complex thing.
Function and task
That yawning occurs because the human brain is not supplied with enough oxygen is one of the theories, but it has turned out to be wrong. Whether much or little oxygen is inhaled, humans do not yawn less or more as a result. Experiments showed that the supply of oxygen or deprivation have no influence on the process. Another thesis of chasmology is that yawning should reinforce attention. If a person is in a state of boredom, in dark rooms or is simply tired, he yawns to become alert again, according to the thesis. In an experiment, the brain activity of various test subjects was measured, who were not allowed to pursue any activity in a dark room. There was a lot of yawning, but the brain activity remained the same. Nevertheless, it can be argued that attempting to yawn in such a situation may well serve to somehow free oneself from the sluggish situation, to do something that breaks the cycle, to cheer oneself up in this way. Thus yawning is also often done in constant activities or while waiting. The process is usually accompanied by stretching of the body, which stimulates it again. So the theory came up that stretching and yawning occur in the same behavioral situations, but not always together. People do stretch when they yawn, but they do not necessarily yawn when they stretch. What yawning actually does is release tension. A tense body becomes more relaxed when a person yawns and in this way frees himself from internal pressure. So yawning is good for stress, excitement or anxiety. Such emotions are better regulated by this process. Likewise, yawning is contagious. If a person yawns, others also start yawning, especially if they are close to each other. This gave rise to the theory that yawning is also related to empathy. Compassionate people yawn along faster than people who are self-fixated or have little ability to empathize with others. Likewise, emotional closeness is a prerequisite for contagious yawning. This doesn’t have to be only with family members or friends; it can even occur between humans and animals. For example, if an animal trusts a human, it actually yawns along with them, which in turn leads to the assumption that cats or dogs also have some empathy.The phenomenon of collective yawning also occurs in groups. This could mean that yawning serves social cohesion and mood transmission.
Diseases and ailments
An important recent hypothesis is the explanation that yawning cools the brain, so it serves thermoregulation. Experiments in animals, including rats, showed that the temperature in the brain rose and then fell again as a result of the process of yawning. In humans, in turn, it was found that the outside temperature had a great influence on yawning. If this was higher than the body temperature, humans yawned more. Likewise, the frequency of yawning differs in summer or winter times. Something similar could be found in endogenous processes, so yawning frequency increases when the body releases a lot of serotonin, dopamine or glutamic acid, and decreases when the release of endorphins is increased. Even in psychotherapy, yawning is now included in treatment to interpret the patient, so that it is considered that yawning, like laughter and crying, is a sign of the road to recovery and serves a processing of painful feelings. It has also been found that schizophrenic patients yawn less frequently, which is due to their impaired self-perception, and autistic patients, in turn, do not yawn along with others, supporting the theory that yawning is related to human empathy.
