 Memory is not like a recording device in the brain in which you rewind the tape and play it back on the Cartesian theater of your mind and the little homunculus in there is watching the screen and reporting to some other part of your brain what it sees happen. There's nothing like that. The moment you ask people to reconstruct a memory of what happened, they start to change it. And the leading researcher on this is Elizabeth Loftus at UC Irvine.