When we experience déjá vu, we feel as though history is repeating itself. We get the most uncanny sensation of intense familiarity, as though we have lived through a particular moment before and are now experiencing it again, even though in reality we’re doing it for the first time. Very often this sense of déja vu occurs over trivial incidents. For example, you might be chatting to a friend in a café about the film you saw recently, and you suddenly feel as though you have done exactly the same thing before, in every detail.
Déjá vu is a French phrase which translated literally, means ‘already seen’. It happens entirely spontaneously and can’t be consciously triggered. Years may go between episodes.
 
What is it?
There are several theories about déjá vu. Some people regard it as nothing more mysterious than a brain malfunction, in which the brain is briefly unable to detect the difference between the present and the past. Indeed, déjá vu is a recognized symptom of temporal-lobe epilepsy: someone has a strong sense of déjá vu shortly before or during an epileptic seizure. Another theory states that it is wish fulfilment on the part of the person having experience, although this doesn’t explain why some very mundane situations can trigger a sense of déjá vu. In psychology, the experience is known as paramnesia. Another theory is that déjá vu is related to a past-life experience, and we feel that we’ve been somewhere before because we have.
I’ve been here before.
Although not every experience of déjá vu is likely to be connected to a past life, some are so striking that the theory is definitely worth considering. As much as 70 percent of the population reports having experienced some form of déjà vu. A higher number of incidents occurs in people 15 to 25 years old than in any other age group.