Everyone yawns, but what exactly is yawning? Why does it happen so uncontrollably, and why is it so contagious?
First off, what exactly is a yawn? What happens inside the body during this time? We know from the outside that our mouths open wide and we inhale. This is so we can breathe in as much air as possible to fill our lungs. Also at this time, your abdominal muscles are being flexed and your diaphragm is being pushed down. Our lungs expand with the air we breathed in, and then we exhale some of that air. The average yawn lasts about six seconds. During this time, our heart rates significantly increase. But what exactly causes us to do this?
Surprisingly, not much research has been done on yawning. But there are a few theories as to why we do. The first one being the physiological theory. This theory says that we yawn to bring more oxygen into our bodies or “remove a buildup of carbon dioxide”. The following question based on this theory lead to further research: “If our bodies make us yawn to draw in needed oxygen, wouldn’t we yawn during exercise?” Developmental neuroscientist, Robert Provine, tested this theory by giving people extra oxygen. This did not decrease yawning. They also tested the theory by decreasing the amount of carbon dioxide in the environment of the subject, which also did not have any affect. The next theory is called he evolution theory. This theory states that our ancestors used yawning as a way to intimidate predators by revealing their teeth. The next theory is the boredom theory. It is obvious that we yawn when we are bored, tired, or drowsy, but this theory brings up the fact that Olympic athletes tend to yawn right before they compete, and how dogs tend to yawn before attacking. This clearly contradicts with the idea of us yawning when we are tired or bored, because these examples are definitely not bored at that time. The last and most recent theory is known as the brain-cooling theory. This theory proposes the idea that people are more likely to yawn during times when their brains are more likely to be warmer. This theory was tested by having subjects breathe through their nose and have hot or cold packs pressed against their foreheads. This is because cold brains can think more clearly, so to sum it up, this theory says that yawning developed to keep us alert.
Why is yawning so contagious? Studies show that contagious yawning could be correlated to “one’s capacity for empathy”. A research study was executed to test this theory. Two groups of subjects, one of autistic children, another of non- autistic children, watched videos of people yawning. Both groups yawned the same amount when viewing the video. But when the groups watched people actually yawning, autistic children yawned much less than the non-autistic children. This helps prove the theory that contagious yawning is linked to ones capacity for empathy because autism affects one’s social interaction skills, therefore showing that autistic children had less empathy towards other’s yawning. The study also showed that children with more severe autism were less likely to yawn.
There are many other interesting facts about yawning. Humans aren’t the only ones who find it contagious, chimps, baboons, and even dogs do too. Yawns are also much more commonly contagious around closer friends rather than a stranger. On a more serious note, excessive yawning could be a sign of disease. It is very rare, but it could point to a heart problem or a number of problems in the brain. And lastly, unborn babies can yawn too!
How long can you go without yawning?
sources:
http://science.howstuffworks.com/life/inside-the-mind/human-brain/question5723.htm
http://www.huffingtonpost.com/2013/06/10/facts-yawning-why-we-yawn-contagious_n_3398301.html
I never thougt that there are so many theories about yawning. Each theory is interesting in its own way . I heard a long time ago that yawning resembels the way first people used to communicate with each other. And when one person yawns, somebody else does it too and it is so because we unconsciously do what our ancestors used to do.
This article is very interesting. I tend to yawn all the time and it seems to be very contagious. I do yawn sometimes when tired or bored, but the majority of the time I’m yawning when I am neither of those things. I’ll yawn especially when I’m about to do something like was said about Olympic athletes. I always that I did it because of nervousness.
As I starting reading this, I actually caught myself yawning. Whether that be from the contagion or my tiredness, I found it ironic and compelling. You mentioned how Olympic athletes tend to yawn before competing, and I actually remember an interview with Olympic speedskater Apolo Ohno where he talked about yawning. This article mentions how it provides a competitive advantage by stimulating a part of the brain that affects consciousness and attentional focus. Yawning is an interesting topic to look in to, and I’m interested to see the future research to be done on it!
This post is really cool! I had no idea that the reason that we yawned was to get rid of carbon dioxide. Its interesting that we yawn because we feel empathy towards another person. I always wondered about why we yawn and whether or not yawning is actually contagious. I always yawn when others yawn which I always thought was weird. It’s also interesting how humans are not the only one with contagious yawns.
This post is really cool! i always wondered about why we yawn and whether or not yawning is actually contagious. I always yawn when others yawn which
I found this pretty great over something as simple as yawning. I have always found that when other people yawn, it causes me to do the same. However, I found it really interesting that humans are not the only ones that find yawning as ‘contagious’ in a sense. Furthermore, I would of never guessed that yawning being contagious could have something to do with someone’s capacity for empathy. Does that mean that people who can not feel empathy yawn less than people who can?