Why do humans dream, and what is their proposed psychological function?

Humans dream to help their brains sort out what happened during the day, like cleaning up a messy room so they can rest better.

Imagine your brain is like a toy box. During the day, you play with all sorts of toys, some are fun, and others are confusing or even upsetting. When you go to sleep, your brain starts cleaning up by putting these toys in order. This cleaning-up process is what makes you dream.

Dreams also help your brain learn new things. It’s like when you’re learning how to ride a bike, sometimes you fall, but the next day, you try again and get better. Your dreams can be like practice time for your brain, helping it remember important stuff or figure out tricky problems.

Sometimes, your brain even makes up silly stories in your dreams, which is just part of the fun! This helps keep your mind happy and ready for the next day.