|What deja vu is and what causes it is a mystery.|
That distinct illusion of having been there and done that has no explanation. The parapsychologist will tell you it's a past life experience. Yogi Berra will remind you it seems like you've felt it before. And most scientists will throw their hands up.
Some believe déjà vu involves emotional responses to similar events; others figure the brain short circuits, sending an event to memory just a split second before putting it into consciousness.
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