DÉJÀ VU
Can Science Explain Deja Vu?
Most of us have experienced deja vu-that sensation when new events feel eerily familiar. Could this "glitch in the Matrix" be a brain short-circuit?
Wait, have I been here before? Have we stood in this exact spot as you said these same words to me at some point in the past? Haven't I seen this very cat pass by this very hallway already? Sometimes, as we experience a new event or place, we get that creepy feeling that it's not the first time. We call that sensation déjà vu, a French phrase that means "already seen." But what is déjà vu, and can science explain why it happens?
DÉJÀ VU COULD BE A MEMORY PHENOMENON
Scientists have tried to effectively recreate déjà vu in the lab. In a 2006 study by Leeds Memory Group, researchers would first create a memory for patients under hypnosis. That memory was usually something simple like playing a game or looking at a printed word in a certain color. Then patients in the different groups were given a suggestion to either forget or remember the memory, which could later trigger the sense of déjà vu when they encountered the game or word.
Other scientists have attempted to bring on déjà vu using virtual reality. One study found that participants reported experiencing déjà vu when moving through the virtual reality Sims video game when one scene was purposefully created to spatially map to another. (For example, all of the bushes in a virtual garden were replaced with piles of trash to create a junkyard with the same layout.)
These experiments have led scientists to suspect that déjà vu is a memory phenomenon. We encounter a situation that is similar to an actual memory but we can't fully recall that memory. So our brain recognizes the similarities between our current experience and one in the past. We're left with a feeling of familiarity that we can't quite place.
Article: scientificamerican.com