Abstract

The warning instruction for the memory illusion during DRM task is one of the simple and effective resolutions to avoid false memory about critical lures. Two experiments were conducted to investigate the effect of warning to reduce false memory and cognitive effort at encoding within DRM paradigm. Fifty-two and forty eight volunteers participated in experiment 1 and 2 each. In experiment 1, the warning instruction and level of processing for study lists were manipulated. Participants were randomly assigned in either warning condition or no-warning condition. They were asked to rate pleasantness for the presenting words or to respond the exact color of words. At the test phase, general recognition test was administrated to observe true and false memory. The warning led less false memory for shallow processing lists relative to deep processing ones. In experiment 2, the warning and generative processing were manipulated. As like experiment 1, half of participants were given a demonstration of the memory illusion and were instructed to avoid it before lists presentation. Participants were informed that 40 words or 40 word fragments would be presented and then they were asked to generate or read the words during the study phase. The warning instruction decreased false memory rates more with read items relative to generated items. The results of two experiments suggest that "cognitive effort" at encoding has advantage to reduce false memory and that the warning for memory illusion can decrease false memory more when the effort is less. The theoretical implications of results were discussed based on activation/monitoring framework.