State Mindfulness and Misinformation Susceptibility.

Two experiments examined whether brief mindful meditation exercises and belief in task utility impacted memory in the misinformation paradigm. Participants watched a fictionalized crime video, received post-event misinformation about the video, and completed a cued recall memory test. They were randomly assigned to complete either a brief mindfulness exercise or unrelated task prior to encoding the video (E1) or prior to the final cued recall test (E2). Further, half of the participants in each group were informed that their assigned task was beneficial to memory performance. In Experiment 1, information about task benefits reduced misinformation reports on the final recall test, regardless of the task. The brief mindfulness exercise increased self-reported mindfulness scores in both experiments. While no group differences in memory were found, correlational analyses across the two experiments suggest that individuals who achieve more intense states of mindfulness may have lower susceptibility to misinformation and better event memory when meditation occurs prior to encoding. The results suggest that brief mindfulness exercises can reliably increase state experiences of mindfulness and have potential for use as experimental manipulations. However, the intensity of a self-guided mindfulness experience can vary across individuals, so it is important to consider individual differences when considering the application of the exercises.

Are witnesses able to avoid highly accessible misinformation? Examining the efficacy of different warnings for high and low accessibility postevent misinformation.

The reliability of eyewitness memory continues to be an area of concern, particularly in situations that involve conflicting sources of information (e.g., the misinformation effect; Loftus et al., 1978, Journal of Experimental Psychology: Human Learning and Memory, 4[1], 19-31). To mitigate the negative effects of misinformation, researchers have examined the efficacy of warnings that highlight the unreliability of postevent information. However, warnings have proven less effective for highly accessible misinformation (Eakin et al., 2003, Journal of Experimental Psychology: Learning, Memory, and Cognition, 29[5], 813-825). In the present study, we examined the effects of different types of warnings for low accessibility misinformation in a standard single test misinformation paradigm, and highly accessible misinformation in a repeated testing misinformation paradigm (Chan et al., 2009, Psychological Science, 20[1], 66-73). We modeled these warnings after Eakin et al. (2003) to include both general warnings and specific question-by-question warnings. We found that warnings were effective in both types of misinformation paradigms. Additionally, memory accuracy in situations where participants were exposed to misleading information was improved when specific and general warnings were combined. We argue that both retrieval blocking of low accessibility items and enhanced contextual discrimination account for these findings.

How prior testing impacts misinformation processing: A dual-task approach.

Research suggests that testing prior to the presentation of misinformation influences how that misinformation is processed. The present study examined the relationship between testing, the demands of misinformation narrative processing, and memory for original and post-event information. Using response latencies to a secondary task, we tested whether prior testing influenced the available resources for secondary task processing. Additionally, we investigated whether changes in narrative processing were specific to critical details tested earlier. Participants engaged in an eyewitness memory paradigm in which half were tested prior to receiving the post-event narrative. Participants responded to the secondary task at specified time points during the narrative. All participants took a final memory test after listening to the post-event narrative. We found that testing interacted with the placement of the secondary task. When responding on the secondary task was closely linked to the presentation of previously tested critical details in the narrative, retrieval-enhanced suggestibility was reduced on tests of event memory (Experiment 1) and increased post-event information learning was revealed on tests of narrative memory (Experiment 2).

An investigation into the impact of acute stress on encoding in older adults.

Acute psychological stress commonly occurs in young and older adults' lives. Though several studies have examined the influence of stress on how young adults learn new information, the present study is the first to directly examine these effects in older adults. Fifty older adults (M age = 71.9) were subjected to either stress induction or a control task before learning two types of information: a short video and a series of pictures. Twenty-four hours later, they were exposed to misleading information about the video and then completed memory tests for the video and pictures. Heart rate and cortisol measures suggest that a physiological stress response was successfully induced. Though pre-encoding stress had little impact on memory accuracy, stress did influence errors of omission on the cued recall test for the video. Findings are discussed in the context of previous research examining the effects of stress on memory in older adults.

The effect of testing can increase or decrease misinformation susceptibility depending on the retention interval.

Research has consistently demonstrated that testing prior to the presentation of misleading post-event information, within the context of a standard eyewitness misinformation paradigm, results in an increase in the misinformation effect. The present study investigated whether changes in misinformation susceptibility in the context of interim testing are affected by retention interval differences between misinformation presentation and final testing. Further, this study tested possible divergences in original and post-event learning between conditions where elaboration in processing of critical details was encouraged either indirectly, via interim testing, or directly, by visually emphasizing critical details. In two experiments, we compared three groups of participants. All participants were exposed to an event, presented with misleading post-event misinformation, and then given a final test on the original event. One group was given an interim test between the original event and the post-event synopsis. A second was presented with a post-event synopsis in which critical details were visually emphasized. A third group served as a baseline comparison group for which synopsis processing was not manipulated. All experimental phases occurred in a single session in Experiment 1. A 48-hour retention interval was inserted between the post-event synopsis and final test in Experiment 2. In Experiment 1, we found that interim testing and emphasizing critical details increased misinformation susceptibility as compared to that found in the standard misinformation group. In Experiment 2, misinformation susceptibility was reduced in the interim testing group. These results suggest that interim testing and emphasizing critical details influence the rate of original detail forgetting. At a longer retention interval, the benefits of testing in learning emerged.

Testing potentiates new learning in the misinformation paradigm.

Retrieval enhanced suggestibility (RES) is the finding that the misinformation effect is exacerbated when a test precedes misleading postevent information (Chan, Thomas, & Bulevich Psychological Science 20: 66-73, 2009). In the present study, we tested three hypotheses relevant to RES. First, we examined whether retrieval of critical details was necessary for the RES effect. Second, we examined whether initial testing influenced the allocation of attention to critical details during postevent information processing. Finally, we examined whether RES resulted in impaired access to the originally learned information. We compared three groups of participants in three experiments: an identical-test group, a related-test group, and a standard misinformation group. Both testing groups were tested on the original event before the introduction of misinformation; however, the identical-test group took the same test before and after the misinformation, whereas the related-test group took different tests before and after misinformation. We found that testing before misleading postevent information affected attention allocation to details in the postevent narrative. Furthermore, the RES effect did not accompany reduced accessibility to the original information, as measured by a modified-modified free recall test. These data have implications for how testing may potentiate new learning.

Effect of repetition lag on priming of unfamiliar visual objects in young and older adults.

Across three experiments, we examined the effect of repetition lag on priming of unfamiliar visual objects in healthy young and older adults. Multiple levels of lag were examined, ranging from short (one to four intervening stimuli) to long (50 + intervening stimuli). In each experiment, subjects viewed a series of new and repeated line drawings of objects and decided whether they depicted structurally possible or impossible figures. Experiment 1 and 2 found similar levels of priming in young and older adults at short and medium lags. At the longer repetition lags (∼20 + intervening stimuli), older adults showed less overall priming, as measured by reaction time (RT) facilitation, than young adults. This indicates that older adults can rapidly encode unfamiliar three-dimensional objects to support priming at shorter lags; however, they cannot maintain these representations over longer intervals. In addition to repetition lag, we also explored the relationship between priming and cognitive reserve, as measured by education and verbal intelligence. In the older adults, higher levels of cognitive reserve were associated with greater RT priming, suggesting that cognitive reserve may mediate the relationship between aging and priming.

Priming correct information reduces the misinformation effect.

The misinformation effect is a well-established phenomenon in the false memory literature, although the mechanisms that underlie it are debated. In the present study, we explored one aspect of the controversy, the fate of the original memory. We began from an activation-based view of memory, capitalizing on the well-understood processes of associative priming and spreading activation, to test the hypothesis that true and suggested information can coexist in memory. After exposure to misinformation, participants were unknowingly primed with associates of either the true or a suggested item. Misled participants who were primed for the true item performed better on a final memory test than did misled participants primed for neutral information. The results indicated that true and suggested information coexist and that retrieval is influenced by each concept's activation level at test. Implications for theories of the misinformation effect were discussed.