The act of yawning is an involuntary reaction that arises when one is very tired or when one is bored, appearing already in the fetus, even during pregnancy, being, in these cases, related to the development of the brain.
However, yawning is not always involuntary, it can also happen due to "contagious yawning", a phenomenon that only appears in humans and in a few animals, such as chimpanzees, dogs, baboons and wolves, occurring whenever you hear, see or one thinks of a yawn.
How contagious yawning happens
Although the specific cause to justify "contagious yawning" is not known, several studies indicate that the phenomenon may be related to each person's capacity for empathy, that is, the ability to put oneself in the other's place.
Thus, when we see someone yawning, our brain imagines that it is in that person's place and, therefore, ends up triggering a yawn, even if we are not tired or bored. This is the same mechanism that occurs when you see someone tapping a hammer on your finger and your body contracts in reaction to the pain that the other person must be experiencing, for example.
Incidentally, another study showed that yawning is more contagious among people in the same family, and then among friends, and then between acquaintances and, finally, strangers, which seems to support the empathy theory, since there is greater facility for put ourselves in the shoes of people we already know.
What can indicate the lack of yawning
Being infected by someone else's yawn is very common and almost always inevitable, however, there are some people who seem not to be affected so easily. Generally, less affected people have some type of psychiatric disorder such as:
- Autism; Schizophrenia.
This is because people with these types of changes usually have greater difficulty in social interaction or communication skills and, therefore, are unable to put themselves in the other person's place, ultimately not being affected.
However, it is also possible that children under 4 years of age do not have "contagious yawning", since empathy only begins to develop after that age.
