We just found out the science behind feeling déjà vu

To think I thought the Matrix movie had clearly explained déjà vu: according to the latest research, déjà vu (French for “already seen”) isn’t just a glitch in the Matrix. It is your brain developing.

According to experts, at least 66% of humans experience déjà vu at least once. While there’s no gender differentiations when it comes to the phenomenon, age does matter. Episodes of reported déjà vu drop dramatically in older adults, with most reports originating from people between the ages of 15 to 25. This has led some researchers to wonder if déjà vu is connected to brain development, as the human brain isn’t fully formed until at least age 25, maybe even later. I know I felt “older” and “wiser” after I turned 25– glad to know there was a reason for it other than my own sense of mortality!

Research shows that déjà vu occurs more frequently for folks from a higher socioeconomic class. It is also frequently reported by people who are highly educated, or those who spend a lot of time watching movies or traveling. This makes sense: déjà vu is all about familiarity-based recognition. People with higher incomes can afford to travel, and travel provides people with more opportunities to see new physical locations that might trigger a sense of familiarity, especially if those locations may have appeared in a previously viewed movie scene. (Whenever I visit New York and stumble across a location from the Sex and the City series, I have to remind myself I haven’t actually been there before– no matter how badly I wish I had Carrie’s shoe collection.)

This isn’t the first time déjà vu has been in the news. A 2010 study found those who frequently remember their dreams have more déjà vu experiences. There’s even a term for dream déjà vu: déjà reve, French for “dreamed before.” About 86% of college students surveyed for the study reported reliving events they remember from dreams. Colorado State University’s déjà vu researcher and cognitive psychologist Anne Cleary believes this might happen when you dream about something you’ve experienced, but later only remember the dream, not the event itself. And now I’m wondering if I really did steal that car, or if I just dreamed it. (Kidding!)

Cleary continued, “Memory is far from perfect. We simply fail to recall everything that we encounter in day-to-day life. However, just because something fails to be recalled doesn’t mean that the memory isn’t still ‘in there’ somewhere; often it is, and it is just failing to be accessed. These types of memories might be what drive the sense of familiarity that presumably underlies déjà vu.”

Does all this sound a bit like science-fiction? Don’t worry– we’re heading that way, anyway. Cleary is using today’s technology to recreate the experience of déjà vu. To this end, she has created a 3-D virtual village she calls “Deja Ville” (clever name) and is using “Deja Ville” to explore the concept of Gestalt familiarity, or the arrangement of objects within a scene.

“For every original scene created, we created another, different scene that mapped onto that original scene in its spatial configuration — the configuration of elements on the grid,” explained Cleary. “For example, if the original scene was a courtyard with a potted tree in the middle, surrounded by flower beds and hanging pots on the courtyard walls, the corresponding similar scene might be a museum with a statue in the middle where the potted tree had been, surrounded by rugs in the same configuration as the flower beds, and candelabra in the same configuration as the hanging pots.”

Cleary also presented her study subjects with completely new scenes, which lacked any similar elements that might be “mapped” and recognized. She found there was a greater likelihood of reported déjà vu experiences when subjects failed to remember one of the previously seen mapped scenes.

She’s now using Deja Ville to see if the memories that underlie a déjà vu experience can help us predict what happens next, serving as a form of “precognition.” I wonder what Philip K. Dick would think of this! Looks like Minority Report might need an update.

According to Cleary, “It’s conceivable that a previous experience that exists in memory but that fails to be retrieved might not only produce a sensation of déjà vu upon encountering a highly similar situation, but also produce a sense of how the current event is supposed to unfold, such as which direction to turn next within the scene.”

“Even when we fail to retrieve a memory,” continued Cleary, “our brains might have a way of signaling to us that there is possibly a relevant memory in there somewhere. That signal might be useful in that it can prompt us to keep searching our memory for whatever it is that is in there that might be relevant to the current situation.”

Well, now I don’t know what to believe. Is my sense of déjà vu due to my love of movies, my unharnessed precognitive abilities, or just a good ol’ fashion memory? I guess I’ll have to wait for science to let me know.

(Image via Warner Bros.)