Why Do We Yawn? It is unclear exactly why we yawn, but the answer may lie in our brain’s ability to regulate temperature. A 2014 study of 120 people found that people yawn less during colder months. Yawning is also beneficial for the body, stretching the lungs and flexing joints. Moreover, it increases blood flow to the face, which can increase alertness.
One possible explanation for yawning is that it physically stimulates the carotid bodies located in the neck. This increases the volume of the lungs by 300 to 400 percent. It also expands the rib cage, which signals the brain that it has taken in enough oxygen to prevent you from feeling breathless.
However, this theory has its critics. For example, this theory does not explain why fetuses yawn. It also cannot explain why yawning is contagious, as the fetus’ brain is not cold. Furthermore, it is unclear why we yawn more frequently before sleep than after. Some researchers suggest that yawning reflects a shift in arousal levels.
The study concludes that yawning has a physiological basis and that it can serve as a social tool for interacting with others. The social component of yawning can see in the yawning of bonobos, where contagious yawning can result in social benefits. However, the psychological benefit of collective yawning remains unexplored. It may be related to our desire to protect our tribe.
