Why do people laugh?

People are the only beings on the planet who are able to laugh.
Such a simple and common thing to all of us as a laugh for scientists is still a mystery. And more questions are raised by the fact that on one and the same unfamiliar joke some people laugh until they drop, while others only shrug their shoulders in puzzlement.
The study of laughter deals with a special section of psychiatry, it is called gelotology. The scientific definition of laughter sounds like this: a complex act that consists of modified respiratory movements associated with a certain facial expression.
Laughter contributes to the production of endorphins and antidepressants, which leads people into a state of appeasement;
Laughter is one of the reactions of a person to humor or tickling;
Laughter can be a sign of nervous tension or mental disorder;
Laughter is not an innate emotion, and it is not transmitted by genotype.
An adult laughs about 17 times a day;
During the laughter, 80 facial muscles are involved;
Laughter from the heart can burn 550 calories in half an hour, and one minute of laughter is equivalent to 10 minutes of fitness;
During laughter, blood pressure decreases, blood supply improves, stress level decreases;
In trying to answer the question of the century, what exactly causes laughter, why little children smile, why girls laugh, where the sense of ridiculousness comes from, scientists spend years. And the exact answer was never found. The expert on laughter Robert Provine spent hours writing down people's conversations, trying to understand what makes them laugh. And he revealed only general patterns - laughter was a reaction to a funny joke, an unexpected resolution of the situation, and sometimes just arose without a reason. But one thing is for sure, laughter is inherent in all people from birth, not as a psychic, but as a physiological feature.
Perhaps laughter is our tool of social interaction. After all, good laughter rallies, makes people easier and closer, but can also quarrel if people laugh at each other, and always without exception attracts the attention of people of the opposite sex.

Source photo:
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