The popular belief that yawning oxygenates the brain has a new thesis: yawning serves to cool the brain and make it work better, as it increases its response speed .
To reach this resolution, an international team of researchers from New York and Vienna conducted an experiment with volunteers in which they measured the frequency of contagion of yawning in passers-by in Vienna (Austria), as well as in Arizona (USA) , both in winter, as in summer. In addition, they conducted a test with images of people yawning where they had to comment on their impressions. The overall results revealed that the subjects in Vienna yawned more in summer than in winter. In Arizona, however, people yawned more in winter than in summer.
When comparing the results, the experts discovered that being exposed in an optimal thermal zone , that is, around 20º Celsius, not only affected the contagion of yawning, but also their mental efficiency . Furthermore, the contagion of yawning decreased when temperatures were quite high, for example 37ºC (in Arizona) or very low, such as 0ºC (in Vienna).
According to the researchers, it is a subconscious mechanism whose objective is to regulate the temperature of the brain. Thus, “as yawning cools the brain, it places it in a condition of optimal homeostasis that can help us react more quickly in a situation of danger or threat,” says Jorg Massen, co-author of the study.
The study, which reveals that yawning when too hot or too cold has no effect on this improvement in brain efficiency, has been published in the journal Physiology & Behavior .
