yawning

behavior

Also known as: yawn

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The Information Architects of Encyclopaedia Britannica

Last updated

July 23, 2026

Quick Summary

Yawning is an involuntary action that humans perform about eight times a day, often when waking up or feeling tired. While the exact reasons are still debated, a prominent theory suggests that yawning helps regulate brain and body temperature.1

How Yawning Works

When you yawn, your jaw stretches, increasing blood flow. The subsequent intake of air cools this blood, acting like a coolant for the brain, especially after periods of intense mental activity.1

Contagious Yawning

The contagious nature of yawning is thought to be linked to empathy, suggesting that seeing someone else yawn might signal a similar need for a "brain cool-down" in ourselves. It may also serve as an alerting mechanism within a group, indicating fatigue or a potentially unsuitable environment.1

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

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speech
Intensity
…automatic reflexes of laughing and yawning illustrate the resonator action of the vocal organ. Together with a widely opened mouth, flat tongue, elevated palate, and maximally widened pharynx, the larynx assumes a lowered position with maximally elevated epiglottis. This configuration is ideal for the unimpeded radiation of the vocal cord…
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…automatic reflexes of laughing and yawning illustrate the resonator action of the vocal organ. Together with a widely opened mouth, flat tongue, elevated palate, and maximally widened pharynx, the larynx assumes a lowered position with maximally elevated epiglottis. This configuration is ideal for the unimpeded radiation of the vocal cord…
Read More

Why Do We Yawn?
…researchers, human beings tend to yawn about eight times per day. That number is probably larger if the day is spent with other people who yawn, or if it’s spent, say, reading an article about yawning. (Are you yawning yet?) The visual of someone yawning, or even simply the thought…
Read More
…researchers, human beings tend to yawn about eight times per day. That number is probably larger if the day is spent with other people who yawn, or if it’s spent, say, reading an article about yawning. (Are you yawning yet?) The visual of someone yawning, or even simply the thought…
Read More