Detecting and Explaining the Sleeper Effect

The sleeper effect occurs when the persuasiveness of a message increases with the passage of time. Although the existence of the sleeper effect has been demonstrated in several recent investigations, the conditions necessary for its observation have not been specified. In the present research, a current view of memory operation is offered to predict the occurrence of the sleeper effect. This view is examined in two experiments. The findings are interpreted as being congenial with the memory explanation. The status of sleeper effect research is assessed in light of these findings.