A yawn is an involuntary action that consists of stretching of the jaw and a deep intake of breath simultaneously, followed by an exhalation. It may be a sign of sleepiness or boredom. This reflex is spontaneous, helping to cool the brain and hence keeps us awake. On the other hand, yawning can be contagious too. Have you ever wondered why you yawn involuntarily when you see or hear someone yawn?
Some psychologists believe that contagious yawning is caused by empathy and social bonding. This is perhaps an innate behaviour that binds us together. We do not develop this subconscious behaviour until the age of four. Interestingly, pack animals such as dogs and chimpanzees catch yawns as a response to seeing others yawn too. However, this behaviour does not apply to autistic children as they may not have the unconscious emotional connection to the people around them.
It has also been suggested that infectious yawning is developed to keep all of us in the group awake and alert. The increase of oxygen intake to our brain is important to get us ready for action. Moreover, contagious yawning may help coordinate sleep cycles and therefore improve social cohesion that glues us together.
Studies have shown that you will catch a yawn when you read about yawning too. Have you yawned since you read this article?
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