How many people have experienced deja vu

Below are some of the more widely accepted theories. The first time you see something, you might take it in out of the corner of your eye or while distracted. Your brain can begin forming a memory of what you see even with the limited amount of information you get from a brief, incomplete glance. So, you might actually take in more than you realize. In other words, it can happen as a sort of mix-up when the part of your brain that tracks present events and the part of your brain that recalls memories are both active.

When your brain absorbs information, it generally follows a specific path from short-term memory storage to long-term memory storage. The theory suggests that, sometimes, short-term memories can take a shortcut to long-term memory storage. Another theory offers the explanation of delayed processing.

You observe something, but the information you take in through your senses is transmitted to your brain along two separate routes. One of these routes gets the information to your brain a little more rapidly than the other. This delay may be extremely insignificant, as measurable time goes, but it still leads your brain to read this single event as two different experiences.

This process of implicit memory leads to the somewhat odd feeling of familiarity. 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. The term deja vu was coined in by the French philosopher Emile Boirac. It is the overwhelming sense that you have already experienced something before.

But there are other, lesser known, phenomena which are thought to be related. Jamais vu - translated as "never seen", this is the sense that something which should be familiar is alien, for example a common word which suddenly seems strange. Presque vu - translated as "almost seen", this is the sense of being on the edge of an epiphany or realisation, for example recalling a memory.

Brain scans appeared normal, suggesting the cause was psychological rather than neurological. Whilst this case on its own does not prove a link between anxiety and deja vu, it raises an interesting question for further study, Dr Moulin says.

Unlike many other memory problems, deja vu seems to occur more in young people. People first experience deja vu at the age of about six or seven, and it happens most often between the ages of 15 and 25, before tailing off as people get older, according to research by Professor Alan Brown at South Methodist University in Dallas. However, none of us can explain it, little understand it.

Michelle Hook. However, Dr. Scientists explain it in the following way. Sensory information travels through several pathways before reaching higher cortical areas of the brain. And they have a real healthy fact-checking frontal part of the brain. What if every new experience felt familiar? Strangely enough, this can happen to some people. In short, nothing feels new to them. This essentially means failing to recognise a situation that, logically, should be familiar.