the majority of peope at one time or another will experience the eerie, almost otherworldly sense of dislocation known as deja vu.
Literally the phrase means "already seen." Itâ??s that uncanny feeling that youâ??ve been in a place before, or dreamed that youâ??ve been in a place, even though you know for a fact youâ??ve never been there, that youâ??re seeing it for the first time in your life.
Youâ??re walking into a room or down a city street and suddenly an overwhelming sensation of familiarity washes over you - and, as suddenly, vanishes: This is not the sort of thing scientists can drag into the lab and put under the microscope.

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He learned that about two-thirds of individuals have experienced déjÃ* vu at least once. People who travel frequently or are better educated are more likely to experience déjÃ* vu. So are political liberals, people who readily recall their dreams, and those with certain types of epilepsy. As people age they seem to have the experience less often.
Why liberals? Are they yearning for elections past? "Maybe because theyâ??re open to different types of experience," Dr. Brown surmises, "experiences outside the mainstream."
DéjÃ* vu commonly involves a place or a scene that seems familiar.
"Setting seems to be a key element to all déjÃ* vu experiences," he says. "There are a couple of explanations for this that could be tested with the right equipment and circumstances." "Weâ??re peeling away the layers, like an onion."
One surprise, which needs further testing, says Dr. Marsh: "The more unique-looking places produce the stronger results. Thatâ??s the opposite of what we expected."

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