After witnessing an event, people often report having seen details that were merely suggested to them. Evidence is mixed regarding how well participants can use confidence judgments to discriminate between their correct and misled memory reports. We tested the prediction that the confidence-accuracy relationship for misled details depends upon the availability of source cues at retrieval. In Experiment 1, participants (N=77) viewed a videotaped staged crime before reading a misleading narrative. After seven minutes or one week, the participants completed a cued recall test for the details of the original event. Prior to completing the test, all participants were warned that the narrative contained misleading details to encourage source monitoring. The results showed that the strength of the confidence-accuracy relationship declined significantly over the delay. We interpret our results in the source monitoring framework. After an extended delay, fewer diagnostic source details were available to participants, increasing reliance on retrieval fluency as a basis for memory and metamemory decisions. We tested this interpretation in a second experiment, in which participants (N=42) completed a source monitoring test instead of a cued recall test. We observed a large effect of retention interval on source monitoring, and no significant effect on item memory. This research emphasizes the importance of securing eyewitness statements as soon as possible after an event, when witnesses are most able to discriminate between information that was personally seen and information obtained from secondary sources.
- Misinformation effect
- Source monitoring