Why do we yawn?

Yawns are fascinating. The fact that it is triggered by a lot of specific emotions varying from tiredness, boredom, to being sleepy is just interesting. What is more fascinating is that yawns are somewhat contagious as you can yawn just after you see someone else do it. So what are these exactly and why do we do it? In this article, we will explore the truth about yawns.

Yawning is an involuntary behavior in which your mouth opens up wide and you inhale deeply followed by exhaling. When you say involuntary, this means that you have no control over this action so much like other reflexes such as blinking or sneezing so you cannot do anything to suppress it nor consciously control it. Yawns are not only exclusive to human beings as all other animals do this. When we yawn, there are various neurochemical changes that happen in our brain.

Although there is no concrete proof as to why we yawn, there are several explanations as to why we yawn. Some researchers have a theory that yawning is a processed used to cool our brains off.

Your brain is like a CPU of a computer. It functions as a machine where all the actions and movements of all your other body parts originate from this part. That is why it is called as the central part of your body or central nervous system because just like a CPU to a computer, you cannot function well if your brain is not functioning well. Because your brain works 24/7, it might 'overheat' just like a CPU will if it does not get the rest it needs or even just some cooling off. So, what the brain does is to inhale cool air, through yawning to cool off the brain.

When you yawn, air comes in and it cools down the brain. When your brain is cool, it tends to function better than when your brain is tired or is nearing 'overheating.' This theory is called the brain-cooling hypothesis or the radiator hypothesis.

Another explanation as to why you yawn is because it is the brain's way of telling you to get more air into your lungs. At a normal rate, you do not get to use majority of your lungs' capacity, hence, the low oxygen levels when you are breathing normally. Therefore, for the lungs to not get stiff due to low levels of oxygen, your brain urges you to sigh or yawn.