By Divya Rajagopal
A mystery of the human body, yawning, is considered to be a sign of tiredness, stress, sleepiness, or even boredom and hunger. It is viewed as a sign of disrespect in some cultures. A yawn is a reflex action, consisting of the simultaneous inhalation of air and the stretching of the eardrums, followed by an exhalation of breath. However, a yawn doesn’t just stop at being an indicator of a mood. Several characteristics have to be considered to validate a hypothesis.
Yawning: a stimulus
A reflex reaction gets triggered due to some external stimulus. For example, the dust particles in the nostrils might make one sneeze. The fascinating part of the yawning mechanism is that the act of yawning is itself the stimuli. The onset of a yawn, triggered by seeing, hearing, reading, or thinking about another person yawning, can cause another yawn. The hypothesis must explain the contagious reaction. When one tries to stop a yawn, some discomfort is felt. It is satisfactory only when the mouth can gape and stretch. Therefore, there is a feedback control system to the brain regarding this reaction. Moreover, it happens not only as a sense of fatigue, but also for awakening, and during other times when the state of alertness is changing.
Low oxygen intake?
There is a common misconception that yawning is triggered when there is low oxygen intake in the lungs. This explains the gaping of the mouth with a slow inhale and a short exhale. Sounds good, but other studies have shown that breathing more oxygen does not decrease yawning. Likewise, breathing more carbon dioxide does not increase yawning. Another theory is that yawning stretches the lungs and the lung tissue. Stretching and yawning may be a way to flex muscles and joints, increase the heart rate, and feel more awake.
Contagious yawning
According to a study at NYU Albany, contagious yawning occurs due to a theory of the mind, that is, an ability to infer or empathise with what others want, know, or intend to do. Seeing or hearing another person yawn may tap a primitive neurological substrate responsible for self-awareness and empathic modelling, which produces a corresponding response in oneself. This is a psychological explanation that describes the phenomenon as a case of peer-pressure, that occurs unconsciously. The experiments validated the contagious factor but did not accord with the bodily changes.
Brain temperature regulation
The most scientifically backed theory about why we yawn is brain temperature regulation. A 2014 study published in Physiology & Behavior looked at the yawning habits of 120 people and found that yawning occurred less during winter. If the brains temperature gets too far outside the norm, inhaling air can help cool it down. During a migraine, your blood clots in your brain. Yawning helps to cool your brain down from that clotting. Yawning makes the body wake up. The motion helps stretch the lungs and their tissues, and it allows the body to flex its muscles and joints. It may also force the blood toward your face and brain in order to increase alertness.
Ways to stop yawning
There are several ways for a person to stop yawning. If you find yourself yawning excessively, try deep breathing exercises through your nose. Your body may need more oxygen. One study also found that nasal breathing decreased contagious yawning completely. You should also get moving. Breaking up a routine can help stimulate your brain. Feelings of tiredness, boredom, and stress tend to make people yawn more. Excessive yawning may also stem from taking too much caffeine and going through an opiate detox. You can also try taking a walk outside or finding a space with a cooler temperature. If you dont have time to do this, drink some cool water or eat a chilled snack, such as fruits or baby carrots. Cold packs on the forehead or washing the face also decreases the brain temperature, and thereby reduces the urge to yawn.
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