The act of yawning is an involuntary reaction that occurs when one is very tired or when one is bored, appearing already in the fetus, still during the gestation, being, in these cases, related to the development of the brain.
However, yawning is not always involuntary, and may also occur due to "contagious yawning", a phenomenon that only occurs in humans and in few animals, such as chimpanzees, dogs, baboons and wolves, occurring whenever one hears, sees or if you think of a yawn.
How does contagious yawning
Although the specific cause for "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 shoes.
So when we see someone yawning, our brain imagines that it is in that person's place, so it ends up triggering a yawn, even if we are not tired or bored. This is the same mechanism that comes when you see someone hammering your finger and our body contracts in response to the pain the other person must be feeling, for example.
Alas, another study, showed that yawning is more contagious among people in the same family, and then among friends, then between acquaintances, and finally among strangers, which seems to support the theory of empathy, since there is more facility for we put ourselves in the shoes of people we already know.
What may indicate lack of yawning
Being infected by someone else's yawn is very common and almost always inevitable, but there are some people who do not seem to be affected so easily. Generally, the least affected people present some type of psychiatric alteration as:
- Autism;
- Schizophrenia.
This is because people with this type of change usually have greater difficulty in social interaction or communication skills and therefore can not put themselves in the other person's shoes, so they are not affected.
However, it is also possible that children under 4 years of age do not have "contagious yawn", since empathy only begins to develop from that age.
