Have you ever walked into a room and been overwhelmed by a feeling of familiarity—even though it’s your first time being there? Or been in the middle of a conversation when it dawns on you: I’ve had this conversation with this person before, despite their insisting that you haven’t? I found myself in this very predicament just last week. I was on the phone with my brother and could swear I’d heard him say those exact words before, as well as his friend talking in the background. But he assured me we hadn’t had that conversation before—I was experiencing déjà vu.
Déjà vu, which means “already seen” in French, is a mysterious phenomenon that some find creepy and others find pretty awesome (like myself). I mean, what is going on? Did you get a peek into the future? Did you experience something similar in a past life? We don’t have a sure answer for you, although there are a few scientific theories that don’t include psychic visions or evidence for reincarnation:
1) You’ve experienced something similar before.
Some researchers believe that déjà vu occurs simply because you’ve entered a familiar-feeling environment or had a similar experience to that of what you’re currently experiencing. For example, you might walk into a restaurant and get a whiff of a meal that just transports you back to the first time your dad took you there. Or you might experience déjà vu during a seemingly insignificant conversation because you’ve had a similar one before. While this is a simple theory, it certainly makes sense in the context of my many experiences with déjà vu.
2) You’re a traveler or a dreamer.
According to a 2003 review in the journal Psychological Bulletin, people who travel often as well as people who remember their dreams are more likely to experience déjà vu than those who don’t travel often and those who can’t describe their dreams. These people obviously have more experiences to draw from—whether they be real-life experiences or those in their dreams—so it comes as no surprise that these individuals experience this phenomenon of intense familiarity.
3) Your brain’s memory circuits might be malfunctioning.
Déjà vu may result from a malfunctioning between long-term and short-term memory circuits in your brain. So basically, it might be our brain taking information about our surroundings straight to long-term memory, sidestepping the typical storage transfer process. This explains why it feels as if we’re experiencing something from the far-gone past instead of the present.
4) Your rhinal cortex—responsible for detecting familiarity—is being activated but your memory circuits are not.
This phenomenon may also be explained by enigmatic activation of the rhinal cortex in your brain, without activation of the memory circuits. This theory would explain why feelings of déjà vu feel very distant, such that you can’t quite put your finger on what or when you’ve experienced that very place or event before. Furthermore, this theory is supported by the fact that stimulation of the rhinal cortex in epilepsy patients brings about feelings of déjà vu.
The aforementioned theories are only that—theories that attempt to explain the mystery that is déjà vu. However, what we do know is that these strange feelings of familiarity are harmless and probably not signs that you’re psychic or flashbacks from a past life. So the next time you’re transported back in time due to a simple smell, sound, or experience, know that you have nothing to worry about and bask in the mystery of it all.