Brain scans show yawning may push fluid out of the brain and boost blood circulation, hinting that yawns help refresh the brain.

Most people seem to be quite sure they understand yawning. They think it is caused by the need for oxygen, or boredom, or sleepiness. A group of medical scientists (Walusinski 2010) have upset this ...

Is it true that we yawn when our brains are deprived of oxygen? Most of us can feel a yawn coming on. The muscles in our jaw begin to tighten, our nostrils might flare, and our eyes might tear up as ...

Among the occupations that get the shortest amount of shuteye each night, several make life-and-death decisions regularly. And members of one profession on the list carry guns on the job. Anybody need ...

Sign up for CNN’s Sleep, But Better newsletter series. Our seven-part guide has helpful hints to achieve better sleep. Find yourself yawning a lot? Do you need that ...

Do you yawn? Well, don’t we not? But how often do you yawn? Does your yawning get so much, so that you gulp three or more cups of coffee to survive through the afternoon? Well, these could be signs of ...

Yawning seems like such a simple act, yet it holds surprising power over us. Just watching someone yawn — even a stranger — can suddenly trigger the irresistible urge to yawn yourself. Why does this ...

(CNN) — Find yourself yawning a lot? Do you need that third or fourth cup of coffee to make it through the afternoon at work? Such signs of sleepiness may be a red flag of a serious sleep deficit that ...