Déjà vu is incredibly complex, and we still can't fully explain it. But like any scientific mystery, theories abound. Swiss scholar Arthur Funkhouser, for instance, thinks there are different kinds of déjà vu. Déjà visité is the feeling that you've already visited a place you know you've never been before, while déjà vecu is the feeling you've already experienced a situation that should be new to you. Scientists also notice that feelings of déjà vu often occur right before someone has a temporal-lobe seizure, which offers its own clues. Others still think it has to do wish fulfillment or a past life experience. The answers are murky at best.
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