How Does Déjà Vu Work?

Déjà vu is when you feel like you’ve already lived through something right now, even though it’s brand new.

Imagine you’re eating your favorite snack, let's say it’s chocolate cookies, and suddenly, you think you've eaten these same cookies before, today. That strange feeling is déjà vu. It's like your brain is saying, “Hey, I’ve seen this before!”

Why does it happen?

Your brain has two parts that help you remember things: one works fast, and the other takes a little longer to catch up.

When something happens, like seeing a familiar place or hearing a familiar song, the fast part of your brain thinks, “I know this!” But the slower part is still catching up. By the time it realizes you're in a new situation, you already felt like you were somewhere else, and that’s why you get déjà vu!

It's like when you're playing with building blocks, and you think you've built that tower before, but actually, it's brand new! Your brain just had a little mix-up.

Take the quiz →

Examples

  1. A student walks into a classroom and suddenly feels like they've been here before, even though it's their first day.
  2. While eating breakfast, someone thinks they’ve had this exact meal at the same time yesterday.
  3. A person sees a stranger on the street and instantly feels like they know them.

Ask a question

See also

Discussion

Recent activity