Why do I yawn excessively

Curious study: if you yawn for a long time, you have more in your head

Is someone who yawns particularly smart? Yes, claims psychologist Andrew Gallup. He sees a direct connection between yawn length and brain volume

Even if a wide-open mouth does not usually look overly intelligent, there is probably a connection between extensive yawning and brain performance. According to a study recently published in the journal "Biology Letters", the one who yawns the longest has the most cells in the cerebral cortex.

"The average yawn length in mammals reliably predicts the size of the brain and the number of cortical neurons," assures psychologist and team leader Andrew Gallup of the State University of New York. Primates, which also include humans, yawn significantly longer than other animals. "These effects cannot be explained by the size of the body or the yawn-specific physique," claim the scientists. Because gorillas, walruses, camels, horses, lions and African elephants all yawn on average shorter than humans.

It is not known exactly why we are yawning

The findings could also lead to a better understanding of what yawning is actually for. Because we still don't know exactly why we're yawning. So far, researchers have often considered the behavior to be a social impulse - if someone starts, the urge to yawn soon spreads across the entire group. According to Gallup, however, the social impulse is not the purpose: the real reason is rather to better blood circulation and cool the brain. The blood circulation, in turn, promotes the ability to think and should possibly even lead to the development of new neural connections.

The different yawning lengths and the connection with intelligence may also fit into the picture. Because it is more likely those who are quick to catch on, who get bored faster in a "hopeless" situation, such as in a lengthy conference or in the face of a not particularly stirring lecture.

To make your boredom and perhaps superior intelligence all too obvious would be impolite, of course. Therefore: hand to your mouth!

Study: Yawn duration predicts brain weight and cortical neuron number in mammals.

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