Most of us experience deja vu at some time in our lives--that feeling that you've done this or seen this before, although you know it's the first time that you've been in the given situation. The most ordinary happening takes on a sense of the strange as the phenomina is usually accompanied by a weird or eerie feeling. In fact, before scientists ever paid any attention to deja vu, it was studied (even named by) psychic researchers.

It is so universal that it was featured in the 1999 blockbuster film The Matrix in a short but critical scene. In the movie, deja vu is a glitch that happens when the Matrix--the computer reality that humans are forced to live in--is reprogrammed. In the real world, it was first seen as a psychic phenominon--and often still is--save for the seemingly silly scientific explanation that our eyes may see things at differing rates.

Under that theory, one eye, thus one part of the brain, experiences something just a moment or two before the other side so that deja vu (and it's counterpart, deja vecu meaning "already lived" versus "already seen") is the slower part of you catching up. At least the new research makes more sense! Reachers had already pinpointed the hippocampus part of the brain as having to do with memory. And recently, Nobel Prize winner Susumu Tonegawa and his team of neuroscientists based at MIT announced finding the actual mechnism of the brain that helps us distinguish between similar situations which, they believe, also helps to explain deja vu.

The three different regions of the hippocampus contribute to learning and memory and the section called the dentate gyrus is what makes us recognize similar things but see the distinctions. When the chemicals of this area misfire, we have a hard time learning a new pattern and running into it again is like seeing it for the first time.

This makes sense in explaining Alzheimer's and, by extention, they use it to explain deja vu and it's increase as one ages. It's perfectly scientific, and they even have the genetically tweaked mice to prove it. It doesn't, however, explain how many times when deja vu occurs, one not only gets that eery feeling that "this has happened before" but can also say what will happen next. Nor does it explain how a majority of the reported instances of deja vu or deja vecu happen between the ages of 15-25, not in advanced age.

Is it possible that the physical aspects of the brain are only a part of what happens with our minds? That some things will never be explained by science? I like to think so.