How Stories in Memory Perpetuate the Continued Influence of False Information

People often encounter information that they subsequently learn is false. Past research has shown that people sometimes continue to use this misinformation in their reasoning, even if they remember that the information is false, which researchers refer to as the continued influence effect. The current work shows that the continued influence effect depends on the stories people have in memory: corrected misinformation was found to have a stronger effect on people's beliefs than information that was topically related to the story if it helped to provide a causal explanation of a story they had read previously. We argue this effect occurs because information that can fill a causal “gap” in a story enhances comprehension of the story event, which allows people to build a complete (if inaccurate) event model that they prefer over an accurate but incomplete event model. This effect is less likely to occur for stories in memory that end in a negative way, presumably because people are more motivated to accurately understand negative outcome events.     

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.     

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.     

Individual differences in false memory from misinformation: Cognitive factors

This research investigated the cognitive correlates of false memories that are induced by the misinformation paradigm. A large sample of Chinese college students (N=436) participated in a misinformation procedure and also took a battery of cognitive tests. Results revealed sizable and systematic individual differences in false memory arising from exposure to misinformation. False memories were significantly and negatively correlated with measures of intelligence (measured with Raven's Advanced Progressive Matrices and Wechsler Adult Intelligence Scale), perception (Motor-Free Visual Perception Test, Change Blindness, and Tone Discrimination), memory (Wechsler Memory Scales and 2-back Working Memory tasks), and face judgement (Face Recognition and Facial Expression Recognition). These findings suggest that people with relatively low intelligence and poor perceptual abilities might be more susceptible to the misinformation effect.     

Psychotropic placebos reduce the misinformation effect by increasing monitoring at test

A psychotropic placebo can help people resist the misinformation effect, an effect thought to be caused by a shift to more stringent source monitoring. When this shift occurs has been unclear. To address this issue we gave some people—but not others—a phoney cognitive-enhancing drug we called R273. Shortly afterwards, everyone took part in a misinformation effect experiment. To gather evidence about source monitoring we surreptitiously recorded time to read the misleading postevent narrative, and response time at test. Our findings suggest that people shifted to more stringent source monitoring at test. Moreover, people with higher working memory capacity (WMC) performed better than people with lower WMC—but only when they were told they had received R273, a finding that fits with research showing that WMC can confer advantages in situations demanding effortful control, but not when automatic heuristics suffice.     

Psychotropic placebos reduce the misinformation effect by increasing monitoring at test

A psychotropic placebo can help people resist the misinformation effect, an effect thought to be caused by a shift to more stringent source monitoring. When this shift occurs has been unclear. To address this issue we gave some people - but not others - a phoney cognitive-enhancing drug we called R273. Shortly afterwards, everyone took part in a misinformation effect experiment. To gather evidence about source monitoring we surreptitiously recorded time to read the misleading postevent narrative, and response time at test. Our findings suggest that people shifted to more stringent source monitoring at test. Moreover, people with higher working memory capacity (WMC) performed better than people with lower WMC - but only when they were told they had received R273, a finding that fits with research showing that WMC can confer advantages in situations demanding effortful control, but not when automatic heuristics suffice.     

Habitual acceptance of misinformation: Examination of individual differences and source attributions

This study identifies individuals who are habitually susceptible to accepting postevent misinformation across testing on three separate events. The results indicate that those individuals identified as habitually susceptible exhibited higher dissociation scores and less of an association between memory accuracy and confidence than did the individuals identified as nonhabitually susceptible. When they were asked to identify the source of the remembered information, similar patterns of source attributions were found for all individuals when they were responding correctly and incorrectly to nonmisinformation and when they were correctly rejecting items of misinformation. Importantly, from a source-monitoring perspective, individuals identified as habitually susceptible demonstrated a different pattern of source attributions than did those classified as nonhabitually susceptible when they were accepting misinformation. Habitually susceptible individuals were as likely to attribute the source of their memory incorrectly to something seen in the experienced event as to attribute it correctly to something read after the fact.     

Discrepancy detection and vulnerability to misleading postevent information

When people are exposed to misleading details after a witnessed event, they often claim that they saw the misleading details as part of the event. We refer to this as themisinformation effect. In four experiments, involving 570 subjects, we explored the role that discrepancy detection plays in the misinformation effect. Experiment 1 showed that subjects who naturally read a post-event narrative more slowly were more resistant to the effects of misleading information contained in the narrative. In Experiment 2, subjects who naturally read more slowly were more likely to detect a discrepancy between what they were reading and what was stored in their memory. In Experiment 3, subjects who were instructed to read slowly were more likely to detect a discrepancy than were those who were instructed to read quickly. In Experiment 4, subjects who were instructed to read slowly were more resistant to misleading postevent information. Taken together, these results suggest that longer reading times are associated with a greater scrutiny of postevent information. This leads to an increased likelihood that discrepancies will be detected and that the misinformation will be resisted.     

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.     

Political Attitudes and the Processing of Misinformation Corrections

Misinformation often continues to influence people’s memory and inferential reasoning after it has been retracted; this is known as the continued influence effect (CIE). Previous research investigating the role of attitude‐based motivated reasoning in this context has found conflicting results: Some studies have found that worldview can have a strong impact on the magnitude of the CIE, such that retractions are less effective if the misinformation is congruent with a person’s relevant attitudes, in which case the retractions can even backfire. Other studies have failed to find evidence for an effect of attitudes on the processing of misinformation corrections. The present study used political misinformation—specifically fictional scenarios involving misconduct by politicians from left‐wing and right‐wing parties—and tested participants identifying with those political parties. Results showed that in this type of scenario, partisan attitudes have an impact on the processing of retractions, in particular (1) if the misinformation relates to a general assertion rather than just a specific singular event and (2) if the misinformation is congruent with a conservative partisanship.     

Misled subjects may know more than their performance implies

Many studies have demonstrated that subjects exposed to misleading postevent information are likely to report the misinformation with confidence on subsequent tests of memory for the event. The purpose of the present studies was to determine whether subjects exposed to misleading postevent information come to believe they remember seeing the misinformation at the original event. A second question addressed by the present studies is whether exposure to misinformation reduces subjects' ability to remember the source of items they witnessed at the original event. In two experiments, subjects viewed a slide sequence depicting an event, were subsequently exposed to misleading information or neutral information about selected aspects of the event, and were later tested on their memory for the source of original and misleading details. The results showed that exposure to misinformation did not lead subjects to believe they remembered seeing the misinformation, nor did it reduce subjects' ability to accurately identify the source of originally seen details. The same pattern of results was obtained whether subjects were tested immediately (Experiment 1) or after a 1-day delay (Experiment 2). Collectively, the results suggest that subjects may report misinformation even if they know they do not remember seeing it.     

False memories in music listening: exploring the misinformation effect and individual difference factors in auditory memory

ABSTRACT

The study of false memory has had a profound impact on our understanding of how and what we remember, as shown by the misinformation paradigm [Loftus, E. F. (2005). Planting misinformation in the human mind: A 30-year investigation of the malleability of memory. Learning & Memory, 12(4), 361–366. doi:10.1101/lm.94705]. Though misinformation effects have been demonstrated extensively within visual tasks, they have not yet been explored in the realm of non-visual auditory stimuli. Thus, the present study aimed to investigate whether post-event information can create false memories of music listening episodes. In addition, we explored individual difference factors potentially associated with false memory susceptibility in music, including age, suggestibility, personality, and musical training. In two music recognition tasks, participants (N?=?151) listened to an initial music track, which unbeknownst to them was missing an instrument. They were then presented with post-event information which either suggested the presence of the missing instrument or did not. The presence of misinformation resulted in significantly poorer performance on the music recognition tasks (d?=?.43), suggesting the existence of false musical memories. A random forest analysis indicated that none of the individual difference factors assessed were significantly associated with misinformation susceptibility. These findings support previous research on the fallibility of human memory and demonstrate, to some extent, the generality of the misinformation effect to a non-visual auditory domain.     

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.     

Who remembers best? Individual differences in memory for events that occurred in a science museum

Individual differences in memory and suggestibility were assessed in an experiment involving 1989 people who attended the Exploratorium, a science museum located in San Francisco. Subjects watched a brief film clip of an assault and later answered questions about it. Approximately half received misinformation about some critical items. Four demographic variables (gender, educational level, age, and occupation) were examined to determine their impact on memory performance. The principle of discrepancy detection predicts that, compared to individuals with a good memory, people who have poor memory to begin with will be relatively suggestible (that is susceptible to misinformation). Some of our findings were consistent with this principle. For example, children (5–10 years) and elderly (over 65) were relatively inaccurate and also relatively suggestible. Other findings were not consistent with the principle, for example the finding that artists and architects were relatively accurate, but they were also highly suggestible.     

How eyewitnesses resist misinformation: Social postwarnings and the monitoring of memory characteristics

Previous findings have been equivocal as to whether the postevent misinformation effect on eyewitness memory is reduced by warnings presented after the misinformation (postwarnings). In the present research, social postwarnings, which characterize the postevent source as a low-credibility individual, diminished the misinformation effect in both cued recall and recognition tests. Discrediting the source as being either untrustworthy or incompetent was effective (Experiment 1). Also, postwarned participants rated reality characteristics of their memories more accurately than did participants receiving no or high-credibility information about the postevent source (Experiment 2). A social postwarning yielded the same results as an explicit source-monitoring appeal and led to longer response times for postevent items, relative to a no-warning condition (Experiments 3 and 4). The findings suggest that the reduced misinformation effect was due to more thorough monitoring of memory characteristics by postwarned participants, rather than to a stricter response criterion or to enhanced event memory.     

Comparison of neural activity that leads to true memories,false memories,and forgetting: An fMRI study of the misinformation effect

False memories can occur when people are exposed to misinformation about a past event. Of interest here are the neural mechanisms of this type of memory failure. In the present study, participants viewed photographic vignettes of common activities during an original event phase (OEP), while we monitored their brain activity using fMRI. Later, in a misinformation phase, participants viewed sentences describing the studied photographs, some of which contained information conflicting with that depicted in the photographs. One day later, participants returned for a surprise item memory recognition test for the content of the photographs. Results showed reliable creation of false memories, in that participants reported information that had been presented in the verbal misinformation but not in the photographs. Several regions were more active during the OEP for later accurate memory than for forgetting, but they were also more active for later false memories, indicating that false memories in this paradigm are not simply caused by failure to encode the original event. There was greater activation in the ventral visual stream for subsequent true memories than for subsequent false memories, however, suggesting that differences in encoding may contribute to later susceptibility to 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.     

Memory distrust and acceptance of misinformation

Relying on a community sample (N = 80), the present study examined whether memory distrust is related to an increased tendency to accept misinformation and whether it interacts with passage of time. Participants were shown video footage of an armed robbery. Approximately 30 minutes later, they were asked to describe as accurately as possible what they had seen. Either 1 day or 2 weeks later they were presented with their own statements, to which five misinformation items had been added. The results showed that people suffering from memory distrust accepted more misinformation than those with optimistic beliefs about their memory. In addition, both age and free recall seemed to modulate this relationship. However, memory evaluation did not interact with time interval. Copyright © 2009 John Wiley & Sons, Ltd.     

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.     

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.