Researchers explore secret origin of deja vu

(Medical Xpress) -- Most people have been in a situation that suddenly feels strangely familiar, while also realizing that they have never been in that specific place before. These experiences are called ‘déjà vu’ and the phenomenon has inspired countless books, songs and movies.
 
What is remarkable about déjà vu, says Western University graduate student Chris Martin, is that the impression of familiarity is accompanied by a sense that the current environment or situation should in fact feel new. But how can it be that a scene or an experience evokes a sense of familiarity but at the same time a feeling that this familiarity is wrong?

Despite the curiosity and excitement about déjà vu in popular culture, these subjective experiences remain poorly understood in scientific terms. Studying déjà vu has proven difficult due to the fleeting nature of these obscure occurrences, and due to the lack of experimental procedures to elicit them in the psychological laboratory.

In an article published online by Neuropsychologia, “Déjà Vu in Unilateral Temporal-Lobe Epilepsy is Associated with Selective Familiarity Impairments on Experimental Tasks of Recognition Memory," Martin and psychology professor Stefan Köhler were able to shed light on this fascinating phenomenon by examining a rare group of neurological patients that experience déjà vu as an early sign of advancing seizures.

Due to lasting underlying brain pathology, most patients with temporal lobe epilepsy exhibit subtle impairments in memory even at times when no seizures are present. Köhler and his team built on this link by seeking behavioural markers of déjà vu on specific memory tasks that were designed to probe feelings of familiarity. The researchers discovered a pattern of performance that clearly distinguished patients with déjà vu from those without.

Specifically, familiarity was selectively impaired only in individuals with déjà vu in their seizure profile. In an experiment that placed different types of memories in conflict, patients with déjà vu were still able to counteract inappropriate feelings of with their ability to recollect pertinent information about previous actual events.

These findings, say Köhler and Martin, open a new window towards understanding the psychological and neural mechanisms that give rise to fleeting, subjective feelings of déjà vu. Köhler says they remind us that even when lasting for just a split second, memory reflect the interplay of many different, sometimes competing processes. On another level, these findings are also of clinical relevance in the surgical treatment of temporal lobe epilepsy.

The study was conducted at Western’s Brain and Mind Institute, in collaboration with clinical scientists at the London Health Sciences Centre and McGill University.

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po6ert
not rated yet Aug 12, 2012
didn't i read this previously? :-)
NameNick
5 / 5 (2) Aug 12, 2012
At no point in during your rant did you come close to journalism. We are all now dumber for having read it. I award you no points, and may God have mercy on your soul.
TheWalrus
not rated yet Aug 13, 2012
I realize I'm not a representative sample, and the following account is in no way scientific. Ignore it if you want. I'm not pretending to be an authority.

I've been intrigued with déjà vu since childhood. I made a point of examining whenever I experienced it. After learning to focus on it and prolong it, I realized that--in my case--almost every instance was an actual "reliving" of a moment. Not in a supernatural way, but due to the odds.

I am a creature of habit. I go to the same places and talk to the same people and do the same things on a regular basis. There are bound to be virtual repeats of some moments.

However, one of my strongest déjà vu experiences occurred after I got my jaw broken. As I sat there dazed, I had the strongest feeling that I knew exactly what was about to happen. That was probably due to the hemispheres of my brain "stuttering" from the shock. I've read accounts of similar experiences, which this article reflects.
Xantos
not rated yet Aug 13, 2012
I don't think déjà vu is just a "brain seizure". I've had moments where I dreamt some trivial experience and then couple of days later it happened exactly as I saw it in my dreams (if dreams really are just dreams). Or there were also moments where something happened almost as I dreamt it. Why this is happening...I don't know. Sure scientists/people will say it's impossible and I don't judge them for that. But I think there is more to brain than just a bunch of cells and really can't wait 'till the technology comes out that would enable me to record my own dreams. That would be the definite proof for or against "foresight" abilities.
Surly
3.7 / 5 (3) Aug 13, 2012
@Xantos: I've had the same experience plenty of times. And after I started keeping a dream journal, I determined that it was always confabulation. Memories, especially memories of dreams, are not reliable.
capbornh
not rated yet Aug 18, 2012
By experience, I can say " dejà vu " is a question of reminiscences, even hidden in unconscious. A similar " mental wave " length, is giving a similar effect.
CapitalismPrevails
1 / 5 (2) Aug 21, 2012
The Matrix is fixing itself. That's all dejà vu is.

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