Deja vu

Been There, Done That IT HAPPENS TO US ALL AT ONETIME OR ANOTHER: DEJA VU, THAT UNCANNY feeling of having experienced something before but being unable to recall exactly when or where. The term comesfrom the French for "already seen,' and is defjned by psychiatrists as "any subjective1y, inappropriate impression of familiarity of a present experience with an undefined past." But that clinical,description hardly does justice to the eerie sense of mystery and unease we feel during such an episode of inexplicable recognition. In The Psychopathology of Everyday Life, Freud placed the déjà vuexperience in "the category of the miraculous" and predicted that the subject would merit the most exhaustive treatment." But because its an evasive phenomenon, deja vu is notoriously difficult tostudy. Most theories are speculative at best. Psychoanalysts, for example, maintain that déjà vu has to do with wish fulfillment. According to this theory, déjà vu is the expression of a wish to repeat apast experience – but this time with a more satisfactory outcome. Parapsychologists, on the other hand, suggest it’s a fleeting glimpse of some past life. But as the brain’s mechanisms for learning andmemory become better understood, scientists are proffering more plausible though still preliminary – explanations of this strange and miraculous act of recollection. A model for one such explanationis the hologram. In a hologram, a kind of three-dimensional photograph, each point in the image contains all the data necessary to reconstruct the image as a whole. "Even the smallest fragment willgive, the complete picture,” says Herman Sno, a psychiatrist at De Heel Hospital outside Amsterdam who has made an extensive study of the scientific literature on deja vu. "But the smaller the fragment,the less sharp the picture will be." If memories are indeed stored in the brain as holograms, each part of the memory contains all the sensory and emotional data needed to recall the entire...