The French term literally translates to “already seen” and is believed to be experienced by at least two thirds of us at some point during our lives. It involves an overwhelming sense that you have experienced the exact same situation before. The term was first coined by a French philosopher in 1876.
Nobody really knows the cause for the sensation but a new report by a group of scientists in the UK, France and Canada looking into one patient’s “chronic” case of deja vu has suggested that anxiety may inspire the feeling. The patient’s condition was so severe that he avoided viewing sources of news like newspapers or television because he felt he had already experienced it all. The sensation would last for minutes during which he would feel like he was simply reliving past experiences.
He even had deja vu about his deja vu experiences, becoming “trapped in a time loop” for eight years. As he became progressively more disturbed and distressed, the sensation developed and became worse. The cause appeared psychological as brain scans appeared normal. Unlike many situations, deja vu is believed to occur more when young, most frequently between the ages of 15-25. The patient was 26 years old.
Dr Chris Moulin, a cognitive neuropsychologist at the University of Burrgogne, described the man’s experiences. “There was one instance where he went to get a haircut. As he walked in, he got a feeling of deja vu. Then he had deja vu of the deja vu. He couldn’t think of anything else,” says Dr Moulin. For eight years, the man felt “trapped in a time loop.” The more distressed he became by the experience, the worse it seemed to get.”
He has encountered other similiar cases before, including when communicating with patients over Skype who believe that they have already met him because of deja vu encounters. Dr Moulin suggested that the deja vu could be exemplified by the anxiety of its occurence and that the root cause could be a “misfiring” of neurons in the brain. He explained “One idea is that deja vu is a sort of ‘brain twitch’. Just as we get muscle spasms, or eye twitches, it could be that the bit of your brain which sends signals to do with familiarity and memory is firing out of turn.”
The case is interesting because it still doesn’t really present a plausible explanation for the sensation. Many people experience deja vu without really considering it afterwards but for those who suffer it “chronically” it raises interesting questions about how it occurs. Perhaps with more research, that “already seen” feeling will one day be explained. The sensation is hard to induce though, although it was successfully created in a lab back in 2006.
