Question: What do fetuses, Koko (the gorilla), non-autistic children and your bestie all have in common?
Answer: The overwhelming ability to involuntarily yawn.
Growing up, we were all told that it was impolite to yawn without covering one’s mouth with our hands (unless we were in utero at 11 weeks when we started, as evidence has shown). And we complied as often as we remembered. But sometimes, you found yourself yawning without even knowing you were opening your mouth wide, dropping your jaw and taking in large quantities of air. That’s what a typical yawn looks like but why do we actually yawn? Believe it or not, what actually causes a yawn is one of the great mysteries of medicine.
It has been a long-held belief that yawning occurred when a person was tired, bored or fatigued. But this theory has fallen by the wayside. Research has shown that instead of being relaxed and drowsy, yawning can make one’s heart rate increase close to 30 percent. In a 2012 study published in Frontiers in Evolutionary Neuroscience, researchers concluded that during a yawn with an average length of 6 seconds, other physiological changes occur besides those in the heart, such as an increase in lung volume and eye tension.
In addition, there have been some suggestions that yawning signals a state of arousal. Yes, even sexual arousal. The boredom theory has also been shot down when dogs were shown to yawn immediately before attacking and athletes prior to a big race or event.
Some of the other theories are:
The need for more oxygen: It is a way for our bodies to expel high amounts of carbon dioxide. Think about how the incidence of yawning goes up when you are one of many in a group in a tight space such as an elevator. High carbon dioxide levels creates the need to draw in more oxygen.
The need to be socially accepted: Robert Provine, Professor of Psychology and Neuroscience at the University of Maryland, discovered that yawning could be compared to laughter when it comes to socially acceptable behavior. If a person hears another laugh, inevitably they chuckle as well. Yawning also seems to be a hard-wired reflex.
The need to cool down your brain: Another study published in Frontiers in Evolutionary Neuroscience analyzed the effects of cold and hot on the brain in terms of yawning. The group led by Andrew Gallup and Omar Elkhar found that in 160 test subjects, more people yawn when their brains are cold than when warm. Alertness is enhanced when our brains are cool and their theory is that yawning was an evolutionary mechanism, i.e. survival of the fittest. Hence, people yawn more during the winter months when the thermometer outside drops.
Most animals yawn but only primates, dogs and human beings older than 4 years of age find yawns contagious. According to research conducted at the University of Tokyo, dogs reacted to their pet owners’ yawning by following in suit, but not nearly as often when they witness a stranger yawning. In fact, it was also shown that dogs only had to hear their owners’ yawn and they would repeat the act. Another study demonstrated that yawning as a contagion is due to the ability to feel empathy. Conducted at Emory University, researchers learned that yawning could be viewed as the highest form of flattery, imitation. We see someone yawn and it causes us to yawn. Thus we feel closer to that individual. It is evidence of human bonding. In another study, autistic children were found to yawn less than their non-autistic peers. Since individuals with autism have a decreased ability to empathize, these results are yet another example that confirms the empathy theory. And finally, Italian researchers Elisabetta Palagi and Ivan Norscia believe that the closer you are to another individual, whether best friend or family, the more you will yawn together.
Hopefully during the course of reading this article, you have not caught too many flies with a yawn. However if your yawning has become excessive, you very well might have an issue that needs medical attention. Please contact one of our medical concierges today at 1-855-863-4537 to schedule a free consultation.
