The Freakonomics guys look at what it means to be able to make memories from scratch:
Psychologists Andrew Clark, Robert A. Nash, Gabrielle Fincham, and Giuliana Mazzoni conducted a three-stage experiment:
In Session 1 participants imitated simple actions, and in Session 2 they saw doctored video-recordings containing clips that falsely suggested they had performed additional (fake) actions. As in earlier studies, this procedure created powerful false memories. In Session 3, participants were debriefed and told that specific actions in the video were not truly performed. Beliefs and memories for all critical actions were tested before and after the debriefing.
The BPS Research Digest summarizes the study’s main conclusion: “The take-home finding is that for 25 per cent of the fake actions, the participants now reported significantly stronger memory scores than belief scores – in other words, their (false) memory of having performed the fake actions persisted even though they often no longer believed they’d performed the actions.”