Laugh is such a weird activity, we make repetitive noises and we grin, show our teeth and sometimes we writhe and cry while experiencing pleasure. But why do we laugh? Laughing creates emotional connection with other people, joking is one of the most important human interaction.
But what makes us laugh? I think we laugh when we look at something in a different way, in a different context, something like a plot twist. You are waiting to hear something but suddenly you hear something that makes your brain to look at the same thing in a very different way, that makes you laugh, that's why you laugh more on psychedelics. It is probably one of the main reasons for laughter, but ofcourse it's much more complex, since laughter predates human speech by potentially millions of years, being a simple form of communication.