Nugget of Knowledge: Yawning

Scientists are unsure why yawns are contagious

YOUNGSTOWN, Ohio (WYTV) – What is a yawn?

It’s primitive. It begins way down in the brainstem — the brain’s basement.

We yawn because we’re sleepy or bored.

The latest research says we don’t yawn to take in extra oxygen. We do yawn to cool the brain: We yawn more in the summer than in winter.

Babies can yawn in the womb, and it begins in the second trimester.

Why does a yawn seem contagious?

Scientists really don’t know.

It may be a way to bond socially with a group, maybe a primitive form of unconscious communication that helped our ancestors stay safe and avoid danger.

It’s all a guess.

Some people are immune to contagious yawning. People with autism, for example, or those with schizophrenia, and children under the age of four.

People may generally become less susceptible to contagious yawning as they age, possibly because they pay less attention to the behavior in others.

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