SUNDAY, FEBRUARY 26, 2012
written by Jordan Gaines —original article found here
Seeing into the future? The neuroscience of déjà vu
Even the most rational of us experience it: you’ll be chatting with friends or exploring a place you’ve never been when suddenly a feeling washes over you: you’ve experienced this exact moment before. The familiarity is overwhelming, and it shouldn’t be familiar at all. The sensation becomes stronger before ebbing, then completely leaves, all within a matter of seconds. Had you predicted the future? Yet, chances are, you can’t pinpoint exactly when you’d experienced that premonition before.
Déjà vu is a French term that literally means “already seen” and is reported to occur in 60-70% of people, most commonly between the ages of 15 and 25. The fact that déjà vu occurs so randomly and rapidly—and in individuals without a medical condition—makes it difficult to study, and why and how the phenomenon occurs is up to much speculation. Psychoanalysts may attribute it to wishful thinking; some psychiatrists cite mismatching in the brain causing us to mistake the present for the past. Still, parapsychologists may even believe it is related to a past-life experience. So what do we know for certain about what happens during an episode of déjà vu?
Some researchers speculate that déjà vu occurs when there is a mismatch in the brain during its constant attempt to create whole perceptions of our world with very limited input. Think about your memory: it only takes small bits of sensory information (a familiar smell, for instance) to bring forth a very detailed recollection. Déjà vu is suggested to be some sort of “mix-up” between sensory input and memory-recalling output. This vague theory, however, does not explain why the episode we experience is not necessarily from a true past event.