Verified answer

The most likely explanation of déjà vu is not that it is an act of "precognition" or "prophecy," but rather that it is an anomaly of memory, giving the impression that an experience is "being recalled." This explanation is substantiated by the fact that the sense of "recollection" at the time is strong in most cases, but that the circumstances of the "previous" experience (when, where, and how the earlier experience occurred) are quite uncertain. Likewise, as time passes, subjects can exhibit a strong recollection of having the "unsettling" experience of déjà vu itself, but little or no recollection of the specifics of the event(s) or circumstance(s) they were "remembering" when they had the déjà vu experience. In particular, this may result from an overlap between the neurological systems responsible for short-term memory and those responsible for long-term memory (events which are perceived as being in the past). The events would be stored into memory before the conscious part of the brain even receives the information and processes it.

Another theory being explored is that of vision. The theory suggests that one eye may record what is seen fractionally faster than the other, creating the "strong recollection" sensation upon the "same" scene being viewed milliseconds later by the opposite eye. However, this theory fails to explain the phenomenon when other sensory inputs are involved, such as hearing or touch. If one, for instance, experiences déjà vu of someone slapping the fingers on his left hand, then the déjà vu feeling is certainly not due to his right hand experiencing the same sensation later than his left hand considering that his right hand would never receive the same sensory input. Also, people with only one eye still report experiencing déjà vu or déjà vécu (a rare disorder of memory, similar to persistent déjà vu). The global phenomenon can therefore at least in certain cases be narrowed down to the brain itself (i.e., one hemisphere being late compared to the other one).

I read an Article on this some time ago (Scientific American I think) Where they explained, That certain similar circumstances can trigger a reflex in your mind where you kind of remember, kind of try to figure out, kind of pick out similarities, etc. And in this process you have an altered brain function where things seem Trippy for a couple seconds, And you sorta remember and have a mini day dream state. I can't really remember the details but it was something like that.