I experience déjà vu every once in a while. While there has been ‘scientific research’ done and it’s been theorized as an anomaly of memory, I love the feeling that I know what’s going down as it’s going down. I experience physical, auditorial, and visual déjà vu. The below ‘scientific explanation is fascinating as it states déjà vu is caused by the brain storing content into memory before the conscious portion processes it. So, déjà vu, based on the below ‘scientific theory,’ is not a precognition, but a defect in the brain.
Déjà vu has been subjected to serious psychological and neurophysiological research. Scientifically speaking, 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; it is 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 (events which are perceived as being in the present) and those responsible for long-term memory (events which are perceived as being in the past). In other words, the events would be stored into memory before the conscious part of the brain even receives the information and processes it. The delay is only of a few milliseconds, and besides, already happened at the time the consciousness of the individual is experiencing it.
Also, in neural studies, more fascinating stuff:
In the late 20th and early 21st Centuries, it was widely believed that déjà vu could be caused by the mis-timing of neuronal firing. This timing error was thought to lead the brain to believe that it was encountering a stimulus for the second time, when in fact, it was simply re-experiencing the same event from a slightly delayed source. A number of variations of these theories exist, with miscommunication of the two cerebral hemispheres and abnormally fast neuronal firing also given as explanations for the sensation.
Usually when I talk about déjà vu it happens shortly after. My neurons should mis-timely fire in the next week, I deduce.