BOB HIRSHON (host):
What’s deja vu? (pause) What’s deja vu? I’m Bob Hirshon and this is Science Update.
A listener named Pourya emailed us from Iran to ask: What is déjà vu? Cognitive psychologist Alan Brown of Southern Methodist University points to three possible explanations: that your brain signals are misfiring or out-of-sync, that you’ve had the experience before but didn’t process it completely the first time, or that there’s one aspect of the experience that’s familiar and that makes everything seem like a replay.
ALAN BROWN (Southern Methodist University):
Let’s say if you walk into a hotel. Maybe an ornate lamp in the corner was on the table at your aunt’s. So your brain lights off the signal of familiarity, but your overall cognition is unable to identify what’s making this feeling of familiarity, so you attribute it to the whole scene.
You can ask us science questions again and again by calling 1-800-why-isit. I’m Bob Hirshon, for AAAS, the science society.