In Defense of the Yawn
“Then all of a sudden, I yawned.
What a rude bastard, but I couldn’t help it!”
Holden Caulfield in A Catcher in the Rye, by J.D. Salinger
When I was training to become a Grinberg Method practitioner, a lot of emphasis was placed on what we call “letting the body work.” This basically means the body is the boss, and if, during a session, it wants to tremble, sweat, go all goosebumpy, cry, giggle, or burp, it should be allowed and encouraged to do so. I could get behind most things my clients’ bodies would do, but at the beginning of my studies, one reaction consistently gave me pause: yawning.
Despite my training, if the person on my table yawned, it was hard to shake the feeling that I was boring them, that they weren’t learning anything, that I wasn’t working on what was really relevant. There were usually a few seconds of panic: should I do something different? open a window? tap dance? For their part, many clients were very self-conscious about yawning during a session, and would go through some impressive macular acrobatics to stifle it. Practice, experience, trusting my work, and trusting the client’s body got me over this, and eventually yawning clients became no big deal. Sometimes I yawn with them. Sometimes I use the yawning to encourage them to breathe more deeply, or relax their jaws.
Still, as involuntary bodily functions go, yawning is almost universally frowned upon, second perhaps only to farting. Yawning is synonymous with fatigue and boredom, and is considered rude in most cultures – especially if it’s done with mouth uncovered.
In preparing for a recent Breath Lab that included experimenting with conscious yawning, I took a closer look at what oscitation (the medical term for it) is all about, and was surprised by what I found.
Birds do it, bees do it…
Well, actually bees don’t yawn. But all mammals, fish, birds, and even snakes do, with the intriguing exception of giraffes and whales. Humans yawn in their first trimester of existence in the womb, and go on to average 250,000 yawns in a lifetime.
If we break it down, yawning consists of opening your mouth, inhaling deeply, hanging at the top of the inhale for a very short time, and then exhaling. Muscles in your face, head, neck, and throat are contracted and stretched – particularly around the jaw – and the Eustachian tubes inside your ears are opened (which is why yawning can sometimes help unblock your ears on an airplane). Your eyes usually close, and may sometimes water. The whole thing lasts an average of 6 seconds.
Though excessive yawning can be a sign of a serious medical condition such as heart or brain disease, for the most part the physiological effects of yawning are beneficial. Heart rate and skin temperature increase, which in turn increases blood flow to the brain, helping it function properly. All those muscles stretching and contracting facilitate lymph flow, which aids in the elimination of toxins from the body. So you can think of yawning as a mini-workout on several levels.
It’s not about needing more sleep or oxygen
Though yawning is a very old reflex in terms of our development and evolution as a species, its purpose is still up for debate among scientists.
Most of us have been taught that we yawn because we need to get more oxygen into our system and release excess carbon dioxide. But studies conducted in the 1980s by American psychologist and yawning expert Robert Provine showed that yawning does not change the level of oxygen or carbon dioxide in the blood. And though yawning is often associated with feeling tired, a 1996 study (R. Baenninger et.al.) demonstrated that yawning frequency is unrelated to prior amounts of sleep.
The most promising explanation for yawning comes from 2011 and 2014 studies led by Andrew Gallup of Princeton University, which conclude that yawning is used by the body to regulate brain temperature. Like a computer, your brain does not function well if it’s overheated. As we now know, when you yawn, your heart rate increases slightly, which elevates blood pressure and brings cooler blood from your lungs and extremities upward into your brain – kind of like a car radiator cooling off the engine.
Gallup found that people were more likely to yawn if the ambient temperature was cooler than their internal body temperature; they yawned much less if the outside temperature was very warm (the air inhaled during the yawn would not serve to cool the brain) or extremely cold (presumably because the brain didn’t need to be cooled or because the cold air was perceived by the body as undesirable). Also, yawning with your mouth wide open allows the walls of your sinuses to expand and contract like bellows, which draws cooler air into your brain.
This thermoregulatory explanation is by now well-documented; yet there are reports of professional musicians yawning just before playing a difficult piece, or parachutists yawning just before they jump out of an airplane. So it would seem that brain-cooling does not account for every yawn. Some studies posit that yawning is used to increase vigilance, others that it lowers stress levels – all of which points to yawning as an activity that marks a behavioral transition, helping the mind and body move from sleeping to waking, rest to movement, or boredom to stimulation (or vice-versa).
Are you yawning yet?
If you’ve started yawning while reading this, don’t be surprised — yawning is highly contagious. You’ve probably noticed that one person yawning can trigger a cascade of yawning around them. Apparently, yawning activates “mirror neurons” in our brain, which are involved in imitating the actions of others. There is much debate as to whether or not yawning contagiously is a sign of an evolved empathic response: some say that sociopaths or people with empathy-related disorders are less likely to yawn when someone else does, but results are inconclusive. For some people, just hearing someone yawn – or even reading about it – is enough to bring one on.
The next time you yawn, whether it’s spontaneous or contagious, don’t repress it. Take it as a wakeup call. Open your jaws wide wide wide. Feel your lungs expanding. If you can do so safely, stretch your arms and your back and open your chest. Use it as a time to ask yourself if you’re hungry, if you need to change activity (stand up, move around, speed up, slow down), or if you need to be alert to something or someone in your environment. If you honor your yawn instead of stifling it, you’ll increase its power to reboot you and connect you with what’s in you and around you.