Reality monitoring and resistance to forgetting under short delay intervals.

In three experiments, participants were asked to perform simple action statements or to imagine performing the actions in a single study session. In a test session that occurred 1 hr, 24 hr, 48 hr (Experiments 1a and 1b), or 1 week later (Experiments 2 and 3), participants were instructed to tell whether the action statement had been carried out or imagined. The primary finding was that, overall, recognition and reality monitoring showed a comparable rate of forgetting. The results add evidence to the hypothesis that, also after long retention delays, discrimination between an internal and an external source may not be inferior to item recognition. A new theoretical proposal to account for these findings is outlined.