What It Is: Wait, haven't you read this before? I swear, it was in some magazine last week. No, really.
New Research Shows: Biologist Susumu Tonegawa of the Massachusetts Institute of Technology recently located the specific receptors in the hippocampus-a pair of neuronal clusters in the center of the brain-that work to tell similar but different places apart. In mice lacking these receptors, a room they've never seen before evokes the same response as a slightly different room they've seen a lot, a sensation that may be similar to dj vu.
What It Means:The hippocampus is the part of your brain responsible for both your sense of direction and the formation of new memories. Dj vu could be simply a temporary disorientation rooted there, as your brain confuses a new location with a remembered one.