Why Do Some People Hear Music in Their Heads?

Some people hear music in their heads because their brain is like a little radio station that plays songs even when no one is singing. It's called earworms. When you hear a song, your brain saves it and sometimes replays it over and over again, just like a favorite tune on repeat.

Sometimes, your brain starts playing a song because of something you see or do. Like if you're walking past a store that's playing a song you love, your brain might start singing it back to you.