INDIANAPOLIS (WISH) – Yawning. It’s characterized as an involuntary process of widely opening the mouth, breathing in deeply and filling the lungs with air followed by a heavy exhale. But why do we yawn and what could it mean?
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When we’re tired
This one shouldn’t come as a surprise, but the mechanism behind a yawn might be. When we’re tired, our bodies slow down and our lungs aren’t able to breathe in as much oxygen to get to our tissues needed to maintain energy. At the same time, our lungs can’t move carbon dioxide out of our system. The involuntary act is a sign that we’re tired, but it’s also our body’s way of resisting it.
When we’re bored
We’ve all been there: sitting in a boring meeting we don’t want to be in, trying to fight the sudden heaviness of our eyelids. When we’re bored, we get tired. The mechanism is the same as described above. It’s our body’s way of preventing us from falling asleep.
To cool our brain
Evidence suggests yawning functions as a way to promote brain cooling. That deep inhale accompanied by the influx of incoming air slightly lowers the brain’s temperature. The jaw also plays a role in cooling the brain. When the muscles of the jaw are stretched, blood flow increases, thus cooling the brain.
Is yawning contagious?
Yes! The likelihood of yawning increases six-fold when we see others do it. It’s a phenomenon called social mirroring, a behavior where humans imitate the actions of others around them.