I Have "The Yawn"

            Out of nowhere, while sitting in class the other day, a yawn escaped from my mouth. “Oh no,” I thought to myself, “I just yawned in the middle of class and my professor saw me! And I’m not even bored or tired…it just… happened!”

            This is not, of course, the best scientific explanation for why I yawned.  However, it illustrates the common occurrence of yawning, which, in reality, is a very interesting and pertinent topic in the field of science.  After all, everyone yawns, but the cause of their yawning is not always known.  According to research and discussion, there are a number of reasons why humans experience the phenomenon of “the yawn.”  Some of these reasons include contagiousness, a means to cool one’s brain, a signal of tiredness, a trigger for alertness, and a mode for displaying empathy.  Each of these explanations for yawning contains a set of observations and interesting stories to explore. 

            One common piece of information surrounding a yawn is its contagiousness.  Writes Heather Hatfield of WebMD, “When one person in a group yawns, over half of the people in the group will yawn within five minutes, and the rest will at least be tempted to yawn” (2).   Furthermore, researcher Robert Provine, who has been researching yawning for more than 20 years, notes that, ‘What is surprising is that virtually anything having to do with yawning triggers a contagious reaction’” (2).  There a number of experiments that could test this belief.  One type of experiment would be a situation in which a person, surrounded by others, yawns, and the people who see the yawn follow suit by yawning themselves.  Specifically, Gordon Gallup ran an experiment in which they recruited forty-four college students to watch, individually, films of people yawning and recorded the number of contagious yawns each volunteer made. Students were told to inhale and exhale in one of four ways: strictly orally; strictly nasally; orally while wearing a nose plug; or just breathe normally.  The results of the experiment included fifty per cent of people who breathed normally or through their mouths yawned while watching other people yawn.  However, none of those told to hold their breathe through their noses yawned (4).  A further aspect of this experiment was the addition of a cold pack.  Students who held a cold pack to their heads did not feel the need to yawn, while those who applied a warm or room temperature pack yawned normally (4).  Applying this to daily life, one interesting example is a psychology professor who attempted to gauge who may be “checking you out” in a public place through the belief that yawning is truly contagious (3).  His theory held that if a person yawned, anyone who is surreptitiously watching the yawner will also not be able to resist yawning, and thus will expose their attention towards the yawner.  This trick is an experiment anyone can do at any time.

            Contagiousness, however, does not explain why the original yawner, who the surrounding persons “caught” the yawn from, first yawned.  Here, Hopper offers insight stating, “Brain cooling explains why you ‘catch’ a yawn” (4).  In other words, when an individual yawns, their brain cools and their blood flow receives a boost. In addition, when a brain is cool, it operates more efficiently.  Thus, combining this information to an evolutionary perspective, the contagiousness of yawns may have evolved out of the need to help raise the attentiveness of a larger, fuller group, which again, occurs through an increased blood flow from a chilled brain.  Even more, this raises many doubts about the connection between yawning and sleeping.  Instead of a yawn promoting sleep, it in fact actually antagonizes it (4). 

            However, as mentioned before, after watching a person yawn, only half of the observed population will physically yawn themselves.  Some scientists explain this percent by arguing that contagiousness occurs with people who experience greater empathy towards others.  Writes Anderson, “Development clues support the empathy theory for contagious yawns… as well as studies of what is actually happening in the brain” (3).  Again, looking at images of the brain taken while a person yawns, one finds greater activity within the self-processing region, which is believed to relate to empathy (3).  Turning to an actual experiment, researchers tested the contagiousness of yawns using psychology and engineering students.  Writes Seward,

Each student was shown to an occupied waiting room where their companion was actually a researcher who yawned 10 times in 10 minutes. The scientists recorded how often the students yawned in response. Each participant was then asked to complete a test of their empathetic skills, in which they analyzed pictures of eyes and recorded the emotions shown (5).

The results of the experiment showed that psychology students were more susceptible to contagious yawning, and indeed, also scored higher on the empathy tests than engineering students.  Seward explains these results by attributing engineering students as more systemized, in that they tend to focus on numbers and formulas, in contrast to psychology students.  However, one wonders if empathy can truly be tested in a standardized way.  Still, empathy in relation to contagiousness is an exciting concept, and one that is continually being tested and researched.

            Hence, yawning, like so many biological functions, is probably not the result of just one thing.  A range of situations and changing circumstances may affect the act of yawning as well as its contagiousness.  Furthermore, the reasons an individual yawns may be interconnected.  So, although I originally intended to end with the statement, “I hope this paper did not make you yawn!,” on second thought, I hope you liked my paper enough to yawn!

Sources:

1-http://en.wikipedia.org/wiki/Yawning

I used this source for background information on yawning, when I was first exploring the topic. .

2-http://men.webmd.com/features/medical-mysteries-she-wrote

3-http://scienceline.org/2007/09/24/ask-anderson-yawn/

4- http://www.newscientist.com/article/mg19426104.400-yawning-may-boost-brains-alertness.html

5- http://news.bbc.co.uk/1/hi/sci/tech/6988155.stm