List strength effect without list length effect in recognition memory

The study of list length effects (adding items to a list affects memory for the other items) and list strength effects (strengthening some items in a list affects memory for the nonstrengthened items) is important to constrain models of memory. In recognition memory, a list length effect is generally found, whereas a list strength effect is not. Using the switched-plurality procedure in an old-new recognition task (e.g., study banana; test bananas), we found the opposite pattern. Length manipulations caused no change in memory performance, whereas strength manipulations did. The list strength effect was found when recollection was likely to operate at test (with switched-plurality lures). When recollection was unlikely to operate (with unrelated lures), the strength effect disappeared. The result was observed using both a size judgement task (which has previously produced positive list strength effects) and a pleasantness judgement task (which has not yielded list strength effects before).     

Are valence and social avoidance associated with the memory conformity effect?

Pairs of participants were shown photographs which varied in terms of valence from negative to positive, and two days later, together, they were given a memory recognition test. When the first person responded the second person saw the response. This affected how the second person responded, what is called memory conformity. The memory conformity effect was larger for previously unseen stimuli (fillers) than for previously seen stimuli (targets), and was greatest for those with low scores on a social avoidance measure. While memory for negative (and most arousing) stimuli was most accurate, the memory conformity effect did not differ significantly by the stimulus valence. Implications for theories of memory malleability and for assessing the reliability of memories in a forensic context are discussed.     

Exploring the memory advantage for moving scenes

Recognition memory is better for moving images than for static images (the dynamic superiority effect), and performance is best when the mode of presentation at test matches that at study (the study–test congruence effect). We investigated the basis for these effects. In Experiment 1, dividing attention during encoding reduced overall performance but had little effect on the dynamic superiority or study–test congruence effects. In addition, these effects were not limited to scenes depicting faces. In Experiment 2, movement improved both old–new recognition and scene orientation judgements. In Experiment 3, movement improved the recognition of studied scenes but also increased the spurious recognition of novel scenes depicting the same people as studied scenes, suggesting that movement increases the identification of individual objects or actors without necessarily improving the retrieval of associated information. We discuss the theoretical implications of these results and highlight directions for future investigation.     

Emotional Valence and Perceived Event Frequency Affect Memory Accuracy for a Personally Relevant Life Event

False autobiographical remembering is known to be affected both by an event's emotional valence and its perceived frequency (PEF). Here, we present a procedure that enables the assessment of retrieval accuracy for details of an overarching personally relevant real‐life event (a graduation ceremony) while taking into account variations in both their valence and PEF. Former university students who attended the same graduation ceremony completed a questionnaire with true and false statements about the ceremony. Their task was to judge whether the event details were true. Event details were previously rated for valence (positive vs. negative) and PEF (high vs. low) and their truth status was confirmed with original video footage from the ceremony. The results showed that valence modulated the effect of PEF on memory accuracy in that a decrease in false memory judgements was observed only for negative low‐PEF (implausible) event details. These results are interpreted within the affect‐as‐information framework. Copyright © 2016 John Wiley & Sons, Ltd.