What is Rapid eye movement (REM)?

Rapid eye movement, or REM, is when your eyes move quickly while you're dreaming.

Imagine you're playing a game where you have to chase after tiny, colorful balls that pop up all over the room, and every time you catch one, another appears somewhere else. That’s kind of what happens in your brain during REM sleep. Your eyes are like little helpers running around, trying to keep up with all the action in your dreams.

During REM, your brain is working really hard, almost like when you're solving a puzzle or learning something new. You might even smile or squirm in your bed, just like when you’re having fun during the day.

But here's the cool part: even though you're sleeping deeply, your body feels almost awake. It’s like being in a dream where you can move and feel things, but you still don’t know you're dreaming, it’s a little bit like pretending to be asleep while playing hide-and-seek!