Why do we experience déjà vu, and how does the brain process it?

We feel like we’ve seen something before, even if it’s completely new, because our brain takes a little extra time to process things.

Déjà vu is like when you’re eating your favorite cereal, and all of a sudden, it feels like you’ve eaten that same bowl of cereal exactly this way before. But you haven’t! It just seems familiar for a moment.

This happens because two parts of the brain are working at the same time, one is fast, and the other is slow. The fast part recognizes something familiar right away, like seeing your mom’s face. The slow part takes more time to check everything out, like counting how many spoonfuls you’ve taken.

Sometimes, the slow part catches up just a little bit later, and poof, it feels like you've been there before! It's kind of like when you press play on your favorite song and then realize you were humming it already.

Your brain has special memory cells that help you remember things. When something happens, these cells send messages back and forth, trying to figure out if they’ve seen this before. If one message arrives just a little late, that’s when déjà vu happens, like a delayed postcard from your memory! We feel like we’ve seen something before, even if it’s completely new, because our brain takes a little extra time to process things.

Déjà vu is like when you’re eating your favorite cereal, and all of a sudden, it feels like you’ve eaten that same bowl of cereal exactly this way before. But you haven’t! It just seems familiar for a moment.

This happens because two parts of the brain are working at the same time, one is fast, and the other is slow. The fast part recognizes something familiar right away, like seeing your mom’s face. The slow part takes more time to check everything out, like counting how many spoonfuls you’ve taken.

Sometimes, the slow part catches up just a little bit later, and poof, it feels like you've been there before! It's kind of like when you press play on your favorite song and then realize you were humming it already.