Just wondering, is there any scientific explanation for having déjà vu?
-- Julia, the net
Hey, Grandma, haven't we answered this question before? Sounds familiar.
"No. And I told you no the last time you asked. Didn't you ask me that yesterday? I'm sure you asked me that yesterday. Just answer the lady's question."
Okay. Okay. Déjà vu. Science. What have we got here. Well, we've got many definitions. Many theories. Quite a bit of research. Nothing definitive, of course. Déjà vu is an aberration of memory that different scientists explain in slightly different ways. Neurologists recognize déjà vu as one frequent accompaniment to temporal lobe seizures, electrical misfirings in a particular part of the brain. Psychiatrists see it in schizophrenic patients. And nearly all of us experience it at some time or other, unrelated to diagnosed seizures or mental illness. Some research indicates that people suffering anxiety or fatigue may be more prone to the eerie feeling.
Most explanations of garden-variety déjà vu propose that although we think we've never been in this place or been through this experience, there are enough common emotional links between our present situation and some dim past event that we muddle the two and call it déjà vu. They're not identical, but close enough that we confuse them emotionally and then physically. One of the problems with the phenomenon is that it likely involves the interaction of three parts of our brains: the amygdala, hippocampus, and temporal lobe, all of which participate in memory and emotion. Science is just beginning to map out that complicated territory. Somewhere in that tangle might be a clearer picture of déjà vu