Why do humans experience déjà vu and how does it relate to memory?

Humans experience déjà vu when their brain thinks it has seen something before, even though it hasn’t, kind of like when you walk into a room and suddenly feel like you’ve been there a hundred times.

Your brain keeps track of things using memory, which is like a picture book. Every time you learn something new or see a place, your brain adds a new page to the book.

Sometimes, your brain gets confused and mixes up two pages, like when you read a word that looks familiar but isn’t quite right. That’s what happens during déjà vu, your brain thinks it’s reading a page it already knows, even though it's actually looking at something new!

Your brain has different parts working together to remember things. One part is like a fast reader who checks the pictures quickly, and another part takes its time to look closely. If they don’t agree on what they’re seeing, boom! You get déjà vu.

It's just your brain doing its best to make sense of everything, even when it’s a little mixed up, and that’s perfectly normal!