Ever go somewhere for the first time and feel like you’ve been there before? Then you announce, “I’m having a déjà-vu!”

Been There, Done That

Having that sensation of déjà-vu is almost creepy. The place looks familiar, but you know you haven’t been there. Is something weird going to happen? Am I having a premonition?

Turns out, this fascinating experience is actually our brain checking its memory. Researchers at the University of Saint Andrews in the UK decided to conduct a study on the phenomenon of déjà-vu. Brain scans showed that during bouts of déjà-vu, it was the frontal area that was active.

The frontal area is more responsible for checking on information and decision-making. It was previously suspected that déjà-vu was a false memory—that would mean that the hippocampus would’ve been active in the scan. But it wasn’t. So really, the sensation is more about the brain checking up on itself, reviewing information. Déjà-vu is not a false memory.

A Tough Test

It was tricky getting the 21 subjects in the study to have a déjà-vu on cue. The scientists actually had to trigger the sensation. They used word associations and left out ”key” words. For example, they repeated words to the participants such as night, bed, pillow, and rest. When the subjects were asked to repeat back the words they remembered, many said “sleep” although that wasn’t one of the original words.

The brain thought it heard sleep because of the other associative words. With déjà-vu, the brain thinks it saw (or heard) something before, and may have, but it’s not there actually now. “It suggests there may be some conflict resolution going on in the brain during déjà vu,” says Stefan Köhler at the University of Western Ontario in Canada.

How’s Your Memory?

This memory thing is kind of a nebulous area. If these findings about déjà-vu are accurate, then here’s what they’re now presupposing: If you experience déjà-vu, it’s a signal that your memory-checking system functions well.

If these findings are confirmed, they propose that déjà vu is a sign that your brain’s memory checking system is working well. So that’s saying that if you don’t ever have déjà-vu, your system doesn’t work as well. Conversely, if you don’t experience déjà-vu maybe your memory is so good, your brain doesn’t need to check it. We’ll have to wait on a new study for those answers.

If you want to read more about current research on the body and the brain, click here.