Mood, motivation, and misinformation: aging and affective state influences on memory

Normative age differences in memory have typically been attributed to declines in basic cognitive and cortical mechanisms. The present study examined the degree to which dominant everyday affect might also be associated with age-related memory errors using the misinformation paradigm. Younger and older adults viewed a positive and a negative event, and then were exposed to misinformation about each event. Older adults exhibited a higher likelihood than young adults of falsely identifying misinformation as having occurred in the events. Consistent with expectations, strength of the misinformation effect was positively associated with dominant mood, and controlling for mood eliminated any age effects. Also, motivation to engage in complex cognitive activity was negatively associated with susceptibility to misinformation, and susceptibility was stronger for negative than for positive events. We argue that motivational processes underlie all of the observed effects, and that such processes are useful in understanding age differences in memory performance.     

The Influence of Social (Mis)Information on Memory for Behavior in an Employment Interview

We examined the impact of misinformation on memory for behavioral information in a social decision making context. In the initial study, 70 subjects viewed an 18-minute simulated employment interview, evaluated the interviewee, and then provided group ratings using their own evaluations and two other evaluations containing misinformation (misled group) or no misinformation (control group). The results of this study revealed that misled subjects were quite accepting of the misinformation, and were highly confident that the misinformation was true. In a supplemental experimental condition, a separate group of 23 subjects was given the same misinformation as the misled group. However, this group was alerted to the fact that they had received some misinformation, prior to completing a recognition memory test. This misled-informed group exhibited the same degree of accuracy as the control group, suggesting that the misinformation effects observed for the original misled group were due to social influence, rather than memory interference or source-attribution errors.     

Advertising's misinformation effect

This research explores whether post-experience advertising alters information learned in a consumer's direct experience. An advertising misinformation effect was obtained for colour memory of a previously seen candy bar wrapper upon both visual and verbal misinformation. However, the misleading visual information produced more ‘remember’ judgements than misleading verbal information. This advertising misinformation effect did not dissipate when the source was discredited. We found that such memory changes can be directly linked to consumer subjective judgements and choices when the misleading information is particularly salient. Not only do these findings constitute a novel generalizability of the misinformation effect, they also have implications for social policy research on deceptive advertising. Copyright © 1998 John Wiley & Sons, Ltd.     

Assessment of calibration for reconstructed eye-witness memories

Two experiments examined confidence judgments associated with eyewitness memory for events to misinformation [Loftus, E. F. (1975). Leading questions and the eyewitness report. Cognitive Psychology, 7, 560-572]. Participants in each experiment watched videos depicting crimes and either responded to questionnaires (Experiment 1) or read narratives (Experiment 2) containing veridical or non-veridical information. Upon testing for memory performance 24 h later, participants exposed to misinformation accepted the misinformation as part of their memory of the events in the videos. In both experiments, confidence judgments of participants subjected to misinformation were high and comparable to those of participants not subjected to misinformation. The relationship between accurate responding and confidence was assessed via calibration analysis [Yates, J. F. (1990). Judgments and decision making. Englewood Cliffs, NJ: Prentice Hall]. Performance on various measures of calibration was generally better for participants who were not exposed to misinformation. We conclude that confidence judgments can depend on factors other than those that improve the accuracy of memory, such as the retrieval fluency of one’s memories.     

Correcting the misinformation effect

Decades of memory research have demonstrated a dire need for effective methods of correcting misinformation, particularly once it has been encoded. However, much of this research has exposed participants to misinformation first then provided a correction, and used indirect memory questions. Using a misinformation effect (ME) paradigm, in which participants' memory is distorted by misleading postevent information, we examine whether corrections can combat memory distortion on direct memory tests. Experiment 1 showed corrections greatly reduced the ME. Experiment 2 replicated this finding with a longer lag time (3 min) between exposure to misinformation and its correction, except for participants that read only the misinformation and its correction. Experiment 3 ruled out the possibility that participants reported the most recent information they read, suggesting participants evaluate the correction's veracity. Finally, a meta‐analysis of the three experiments reiterates that corrections may be effective in combating misinformation.     

The selective power of causality on memory errors

We tested the influence of causal links on the production of memory errors in a misinformation paradigm. Participants studied a set of statements about a person, which were presented as either individual statements or pairs of causally linked statements. Participants were then provided with causally plausible and causally implausible misinformation. We hypothesised that studying information connected with causal links would promote representing information in a more abstract manner. As such, we predicted that causal information would not provide an overall protection against memory errors, but rather would preferentially help in the rejection of misinformation that was causally implausible, given the learned causal links. In two experiments, we measured whether the causal linkage of information would be generally protective against all memory errors or only selectively protective against certain types of memory errors. Causal links helped participants reject implausible memory lures, but did not protect against plausible lures. Our results suggest that causal information may promote an abstract storage of information that helps prevent only specific types of memory errors.     

Comparing the influence of directly vs. indirectly encountered post-event misinformation on eyewitness remembering

Some research has found a stronger influence of directly (face-to-face; co-witness; ‘social’) vs. indirectly (through written reports, ‘non-social’) encountered post-event misinformation on eyewitness memory reports, whereas other research finds no (big) difference. We argue and demonstrate that a crucial but so far neglected variable underlying this difference is memory for the misleading information itself. In a study with N = 120 participants who encountered misinformation directly or indirectly, we found misinformation retention (as assessed in a separate test) to be positively associated with a broad range of misinformation effects. Influence type (direct vs. indirect), however, did not moderate the misinformation effect in terms of memory for original details, and misinformation endorsement was even weaker in the direct influence condition. In our view, these findings reflect differential conversion of retained misinformation into test performance. Other than this, influence type had essentially no effects on remembering; nor did an additional post-warning manipulation.     

Examining the effects of memory specificity and perceptual load on susceptibility to misleading information

Our study aimed to examine the role of perceptual load in eyewitness memory and susceptibility to misinformation and establish whether trait-based memory specificity protects against misinformation. Participants (n = 264) viewed a video depicting a crime and completed a memory questionnaire immediately afterwards and 1 week later. Memory specificity was measured using the Autobiographical Memory Test (AMT). Higher AMT scores were associated with better memory accuracy. Performance was worse in the high load compared to the low load condition at immediate recall. However, this effect was not seen for every question and load did not influence eyewitness identifications. To test the possibility that load effects were not fully captured by the questionnaire in experiment 1, we conducted a second experiment (n = 120) where we systematically manipulated misinformation about central and peripheral details. We found no effects. Our findings suggest that high perceptual load enhances eyewitness suggestibility, while specific autobiographical memory protects against misinformation.     

An experimental investigation of the misinformation effect in crime-related amnesia claims

Research suggests that both internal (i.e., lying) and external (i.e., misinformation) factors can affect memory for a crime. We aimed to explore the effects of post-event misinformation on crime-related amnesia claims. We showed participants a mock crime and asked them to either simulate amnesia (simulators) or confess to it (confessors). Next, some participants were provided with misinformation. Finally, all participants were requested to genuinely recollect the crime. Overall, simulators reported less correct information than confessors. Moreover, these two groups were equally vulnerable to misinformation. In addition, exploratory analyses on strategies adopted by simulators revealed that those who previously, mostly omitted information while simulating amnesia exhibited the lowest amount of correct details. Simulators who instead used a mixed strategy disclosed more fabricated memory errors. Findings suggest that legal professionals and jurors should take into account that even offenders, irrespective of confessing or simulating memory loss for a crime, can be susceptible to post-event misinformation.     

An individual differences approach to the suggestibility of memory over time

We examined how certain personality traits might relate to the formation of suggestive memory over time. We hypothesised that compliance and trust relate to initial acceptance of misinformation as memory, whereas fantasy proneness might relate to integration of misinformation into memory after later intervals (relative to the time of exposure to misinformation). Participants watched an excerpt from a movie—the simulated eyewitness event. They next answered a recall test that included embedded misinformation about the movie. Participants then answered a yes/no recognition test. A week later, participants answered a second yes/no recognition test about the movie (each yes/no recognition test included different questions). Before both recognition tests, participants were warned about the misinformation shown during recall and were asked to base their answer on the movie excerpt only. After completing the second recognition test, participants answered questions from the Neuroticism Extroversion Openness Personality Inventory-3 (McCrae, Costa, & Martin, 2005) and Creative Experiences Questionnaire (Merckelbach, Horselenberg, & Muris, 2001). While compliance correlated with misinformation effects immediately after exposure to misinformation, fantasy-prone personality accounted for more of the variability in false recognition rates than compliance after a 1-week interval.     

Undoing suggestive influence on memory: The reversibility of the eyewitness misinformation effect

Presenting inconsistent postevent information about a witnessed incident typically decreases the accuracy of memory reports concerning that event (the misinformation effect). Surprisingly, the reversibility of the effect (after an initial occurrence) has remained largely unexplored. Based on a memory conversion theoretical framework and associated refined assessment strategy, we report three experiments to demonstrate that suggestive influence can be completely undone. Initially established misinformation effects were eliminated - even after a period of 5weeks (Exp. 3) - through (a) an enlightenment procedure ensuring an adequate representation of the memory task as a search for potentially two contradictory items (instead of "the" single "correct" answer) and (b) using a memory state test that unconfounds the performance contributions of item and source memory by assessing them separately. Specifically, memory for original event details that were the target of misinformation was restored to the level of non-misled control performance, and even beyond (Exp. 3). This remarkable reversibility of misinformation influence highlights the central role of memory conversion processes in the misinformation effect (but does not principally exclude the contribution of traditional interference processes). We discuss the compatibility of our findings with previous research and make suggestions for real-world eyewitness interrogation.     

Influences of misleading postevent information: misinformation interference and acceptance

Because of the biasing nature of retrieval tests, evidence that the introduction of misleading postevent information will impair the memory for an original event has recently been in dispute. In two experiments, a retrieval test sensitive to both biasing effects of misinformation (misinformation acceptance) and influences of the misinformation on memory (misinformation interference) was used. Both experiments demonstrated misinformation acceptance, and one of the experiments suggested that misinformation interferes with the ability to remember the original event. Two misinformation interference hypotheses are evaluated; they suggest that the misinformation may have either impaired memory or led to confusion regarding what had occurred during the event.     

The role of commitment in producing misinformation effects in eyewitness memory

We conducted three experiments exploring conditions in which misleading postevent information interferes with people’s ability to remember details about an event they witnessed. The key condition included in each experiment was the misled-plus-commit condition. After viewing slides depicting a crime, subjects in this condition read a narrative that contained misinformation. Following the narrative, they completed an interpolated recognition test that induced them to select the misinformation. Assessment of memory for the slides using a final, modified recognition test indicated that performance in the misled-plus-commit condition was most frequently near chance, whereas performance in the control condition was far above chance. This result was obtained on four separate occasions and indicates that prior retrieval of misinformation impairs memory. Another important finding was that the deleterious effect of passively reading about misinformation in a narrative is not as great as the effect of reading about it and then selecting it on an interpolated test. Actively retrieving misinformation seems to cause particularly deleterious effects. Our conclusion is that the findings are compatible with the retrieval blocking hypothesis, which assumes that repeated retrieval of misinformation blocks access to the witnessed information.     

Reactions to blatantly contradictory information

In two experiments, subjects were shown a complex event and were later exposed to misinformation about that event. In addition, some subjects received a piece of blatantly contradictory misinformation. Blatant misinformation both was rejected by subjects and caused them to be more resistant to other misinformation that they would ordinarily have been inclined to accept the “spillover” effect. However, delaying the blatant misinformation until the other pieces of false information had already been processed destroyed its ability to make subjects immune to such “ordinary” misinformation. These results are consistent with the idea that subjects incorporate new information into memory at the time it is initially introduced and use this information to update an existing memorial representation.     

Children's eyewitness memory: Repeating post-event misinformation reduces the distinctiveness of a witnessed event

Children may incorporate misinformation into reports of witnessed events, particularly if the misinformation is repeated. One explanation is that the misinformation trace is strengthened by repetition. Alternatively, repeating misinformation may reduce the discriminability between event and misinformation sources, increasing interference between them. We tested trace strength and distinctiveness accounts by showing 5- and 6-year-olds an event and then presenting either the “same” or “varying” items of post-event misinformation across three iterations. Performance was compared to a baseline in which misinformation was presented once. Repeating the same misinformation increased suggestibility when misinformation was erroneously attributed to both event and misinformation sources, supporting a trace strength interpretation. However, suggestibility measured by attributing misinformation solely to the event, was lower when misinformation was presented repeatedly rather than once. In contrast, identification of the correct source of the event was less likely if the misinformation was repeated, whether the same or different across iterations. Thus a reduction in the distinctiveness of sources disrupted memory for the event source. Moreover, there was strong association between memory for the event and a measure of distinctiveness of sources, which takes into account both the number of confusable source and their apparent temporal spacing from the point of retrieval.     

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.     

False Remembering in the Aged

ABSTRACT— Researchers studying human memory have increasingly focused on memory accuracy in aging populations. In this article we briefly review the literature on memory accuracy in healthy older adults. The prevailing evidence indicates that, compared to younger adults, older adults exhibit both diminished memory accuracy and greater susceptibility to misinformation. In addition, older adults demonstrate high levels of confidence in their false memories. We suggest an explanatory framework for the high level of false memories observed in older adults, a framework based on the theory that consciously controlled uses of memory decline with age, making older adults more susceptible to false memories that rely on automatic processes. We also point to future research that may remedy such deficits in accuracy.     

Recalling a Witnessed Event Increases Eyewitness Suggestibility: The Reversed Testing Effect

ABSTRACT— People's later memory of an event can be altered by exposure to misinformation about that event. The typical misinformation paradigm, however, does not include a recall test prior to the introduction of misinformation, contrary to what real-life eyewitnesses encounter when they report to a 911 operator or crime-scene officer. Because retrieval is a powerful memory enhancer (the testing effect), recalling a witnessed event prior to receiving misinformation about it should reduce eyewitness suggestibility. We show, however, that immediate cued recall actually exacerbates the later misinformation effect for both younger and older adults. The reversed testing effect we observed was based on two mechanisms: First, immediate cued recall enhanced learning of the misinformation; second, the initially recalled details became particularly susceptible to interference from later misinformation, a finding suggesting that even human episodic memory may undergo a reconsolidation process. These results show that real-life eyewitness memory may be even more susceptible to misinformation than is currently envisioned.     

Trauma and memory: effects of post-event misinformation, retrieval order, and retention interval

The present study concerned effects of misinformation, retrieval order, and retention interval on eyewitness memory for a traumatic event (a vivid murder). Relations between misinformation acceptance and compliance were also examined. The classic three-stage misinformation paradigm (Loftus, 1979) was employed, with a multi-component recognition test added. Either immediately or 2 weeks after viewing a distressing film, 232 adults read a narrative (misleading or control) about the murder and then took a recognition test that tapped memory for central and peripheral details. Test-item order either matched the chronology of the film or was randomly determined. Significant misinformation effects were obtained. Moreover, control participants were more accurate in response to questions about central than peripheral information; however, this was not so for misinformed participants. Sequential but not random retrieval order resulted in a higher proportion of correct responses for central as opposed to peripheral misinformation questions. Compliance was significantly related to misinformation effects. Delay increased participants' suggestibility, impaired memory accuracy, and produced higher confidence ratings for misinformed participants compared to controls. Findings indicate that even for a highly negative event, adults' memory is not immune to inaccuracies and suggestive influences.     

Decreased susceptibility to false memories from misinformation in hormonal contraception users

Sex hormones are increasingly implicated in memory formation. Recent literature has documented a relationship between hormones and emotional memory and sex differences, which are likely related to hormones, have long been demonstrated in a variety of mnemonic domains, including false memories. Hormonal contraception (HC), which alters sex hormones, has been associated with a bias towards gist memory and away from detailed memory in women who use it during an emotional memory task. Here, we investigated whether HC was associated with changes in susceptibility to false memories, which may be related to the formation of gist memories. We tested false memory susceptibility using two well-validated false memory paradigms: the Deese–Roediger–McDermott (DRM) task, and a story-based misinformation task. We found that hormonal contraceptive users were less susceptible to false memories compared to non-users in the misinformation task, and no differences were seen between groups on the DRM task. We hypothesise that the differences in false memories from the misinformation task may be related to hormonal contraceptive users' memory bias away from details, towards gist memory.