How jokes work

The essence of most jokes is that the key line is reported from something terrible or painful that happened to the hero of the story. The unexpected end "scares" our brain, and we laugh, making sounds similar to those that chimpanzees warn their relatives about the impending danger. Although we understand that the anecdote is not related to a real event, our laughter contributes to the production of endorphins, which relieve the feeling of pain that would have arisen if the joke were a reality. If all this really happened, we would have started crying, and our brain would also have produced endorphins. Crying is often a continuation of laughter. That is why in moments of serious emotional crisis, for example, at the news of death, a person who mentally cannot accept the incident begins to laugh hysterically. When he realizes what happened, the laughter turns into crying.

Human laughter comes from threatening signals used by primates.