Three types of deja vu

As I was traveling to Mumbai for the FMS entrance exam, I saw a slaughter house in the way. I was trying to find out the synonyms for the same and the word abattoir crossed my mind. Then I started wondering what how many people might know the word if it came in that day's exam.

While writing the exam, I was really surprised to find a straight-forward question about the meaning of the word abattoir. Now this may not be exactly deja vu, but there have been many, many instances where I have felt that I have seen a certain scene before or I have already lived through certain sequences of events sometime. I can clearly recall what the other person will say or do. After a few seconds the whole experience disappears. I've tried to find out the cause of this amazing phenomenon. A few answers I found on the net and in books include:-

1. It is a kind of wish-fulfillment. The brain wants to repeat a past event with more satisfactory conclusions.
2. Another theory states that a certain image, sound or a scene evokes a past scene from the memory which had a similar setting and thus the brain mistakes it for the past.
3. Deja vu has also been associated with temporal-lobe epilepsy.
4. But my favourite explanation is the one which says that there is a slight delay between perception and cognition in the brain. Sometimes what you see and feel gets detoured in the brain before you have a chance to interpret it. This experience is stored in the memory. The delay causes the brain to think that the event happened in the past when actually it has been stored just a few moments ago. Interesting. However this informative article criticizes the generalization of deja vu and divided it into three parts - deja vecu, deja senti and deja visite.