Every time I sit down to begin a project, MCAT practice, or even to write an exam, I begin excessively yawning. In the moment, I used to wonder why I was suddenly overcome with fatigue when I’m actually shitting myself and extremely nervous to complete whatever task I’m about to begin. Yesterday, I was fine all morning and then the excessive yawning began again when I tried to an MCAT practice passage. Curious to see if yawning was somehow related to anxiety, I swiftly googled it. To my surprise, yawning can be a result of nervousness, stress, and anxiety (Wired).

This behavior of excessive yawning is common to almost all of us living beings (i.e. reptiles, animals, humans, fish). According to the article Big Question: Why Do I Yawn When I’m Nervous or Stressed?, researchers found many studies that link yawning to stress. They believe that our hypothalamus, a part of the brain that maintain’s our body’s homeostasis, triggers the behavior of yawning during such stressful situations.

“In one study, male Siamese fighting fish were observed yawning multiple times during different aggressive encounters with one another. Similarly, numerous studies have shown that macaques will yawn in response to various male threats, bouts of sexual jealousy, and anxiety. In a recent study published in Neuroscience Letters, Japanese researchers used classic fear conditioning to successfully induce yawning in rats.” – Wired

One specific reason for this behavior that I found particularly interesting is that yawning can act as a mechanism to maintain our body’s temperature. Under stressful or anxiety provoking situations, we tend to sweat more because of our rising body temperature. Therefore, yawning helps to combat this temperature increase by keeping “the brain at its optimal 98.6 degree temperature.”

“In a 2010 study on the impact of yawning on brain temperature, Gallup implanted probes in the brains of rats and found that even a rise in temperature of 0.18 degrees Fahrenheit triggered yawning. He also found that the skull temperature fell immediately after the rats finished their yawns—sometimes by as much as 0.7 degrees.” – Wired

The next time you catch yourself excessively yawning, instead of reaching for another cup of coffee (like I naively used to do), just check in with your body and note any signs of stress, anxiety, or nervousness.