Creating false memories for events that occurred before versus after the offset of childhood amnesia

We examined whether false images and memories for childhood events are more likely when the event supposedly took place during the period of childhood amnesia. Over three interviews, participants recalled six events: five true and one false. Some participants were told that the false event happened when they were 2 years old (Age 2 group), while others were told that it happened when they were 10 years old (Age 10 group). We compared participants’ reports of the false event to their reports of a true event from the same age. Consistent with prior research on childhood amnesia, participants in the Age 10 group were more likely than participants in the Age 2 group to remember their true event and they reported more information about it. Participants in the Age 2 group, on the other hand, were more likely to develop false images and memories than participants in the Age 10 group. Furthermore, once a false image or memory developed, there were no age-related differences in the amount of information participants reported about the false event. We conclude that childhood amnesia increases our susceptibility to false suggestion, thus our results have implications for court cases where early memories are at issue.     

Creating false memories for events that occurred before versus after the offset of childhood amnesia

We examined whether false images and memories for childhood events are more likely when the event supposedly took place during the period of childhood amnesia. Over three interviews, participants recalled six events: five true and one false. Some participants were told that the false event happened when they were 2 years old (Age 2 group), while others were told that it happened when they were 10 years old (Age 10 group). We compared participants' reports of the false event to their reports of a true event from the same age. Consistent with prior research on childhood amnesia, participants in the Age 10 group were more likely than participants in the Age 2 group to remember their true event and they reported more information about it. Participants in the Age 2 group, on the other hand, were more likely to develop false images and memories than participants in the Age 10 group. Furthermore, once a false image or memory developed, there were no age-related differences in the amount of information participants reported about the false event. We conclude that childhood amnesia increases our susceptibility to false suggestion, thus our results have implications for court cases where early memories are at issue.     

“You and your best friend Suzy put Slime in Ms. Smollett’s desk”: Producing false memories with self-relevant details

Rates of false memory reports vary markedly in the published literature. In an effort to explain these differences, the present study investigated the effects of including different types of details in a false narrative upon subsequent false memory formation. Participants were assigned to one of four conditions in which the inclusion of self-relevant and/or specific details in a false event (putting a toy in a teacher's desk) was manipulated. Participants engaged in a standard memory recovery procedure over three interviews, involving recall for three true and one false event Upon completion, 68.2% of participants in self-relevant groups were judged as having created memories or images about the false event, as compared with 36.4% in non-self-relevant groups. Subjective ratings of memory intensity were higher for self-relevant groups, and self-relevant participants were less likely to correctly guess the false event. These findings indicate that including self-relevant details in suggested childhood events increases the likelihood that such events will be accepted as false memories.     

Emotional content of true and false memories

Many people believe that emotional memories (including those that arise in therapy) are particularly likely to represent true events because of their emotional content. But is emotional content a reliable indicator of memory accuracy? The current research assessed the emotional content of participants’ pre-existing (true) and manipulated (false) memories for childhood events. False memories for one of three emotional childhood events were planted using a suggestive manipulation and then compared, along several subjective dimensions, with other participants’ true memories. On most emotional dimensions (e.g., how emotional was this event for you?), true and false memories were indistinguishable. On a few measures (e.g., intensity of feelings at the time of the event), true memories were more emotional than false memories in the aggregate, yet true and false memories were equally likely to be rated as uniformly emotional. These results suggest that even substantial emotional content may not reliably indicate memory accuracy.     

Comparing recollective experience in true and false autobiographical memories

This study investigated whether true autobiographical memories are qualitatively distinct from false autobiographical memories using a variation of the interview method originally reported by E. F. Loftus and J. Pickrell (1995). Participants recalled events provided by parents on 3 separate occasions and were asked to imagine true and false unremembered events. True memories were rated by both participants and observers as more rich in recollective experience and were rated by participants as more important, more emotionally intense, as having clearer imagery, and as less typical than false memories. Rehearsal frequency was used as a covariate, eliminating these effects. Imagery in true memories was most often viewed from the field perspective, whereas imagery in false memories was most often viewed from the observer perspective. More information was communicated in true memories, and true memories contained more information concerning the consequences of described events. Results suggest repeated remembering can make false memories more rich in recollective experience and more like true memories. Differences between true and false memories suggest some potentially distinct characteristics of false memories and provide insight into the process of false memory creation.     

False memories of fabricated political events

In the largest false memory study to date, 5,269 participants were asked about their memories for three true and one of five fabricated political events. Each fabricated event was accompanied by a photographic image purportedly depicting that event. Approximately half the participants falsely remembered that the false event happened, with 27% remembering that they saw the events happen on the news. Political orientation appeared to influence the formation of false memories, with conservatives more likely to falsely remember seeing Barack Obama shaking hands with the president of Iran, and liberals more likely to remember George W. Bush vacationing with a baseball celebrity during the Hurricane Katrina disaster. A follow-up study supported the explanation that events are more easily implanted in memory when they are congruent with a person's preexisting attitudes and evaluations, in part because attitude-congruent false events promote feelings of recognition and familiarity, which in turn interfere with source attributions.     

Autobiographical elaboration reduces memory distortion: cognitive operations and the distinctiveness heuristic

Retrieval monitoring enhances episodic memory accuracy. For instance, false recognition is reduced when participants base their decisions on more distinctive recollections, a retrieval monitoring process called the distinctiveness heuristic. The experiments reported here tested the hypothesis that autobiographical elaboration during study (i.e., generating autobiographical memories in response to cue words) would lead to more distinctive recollections than other item-specific encoding tasks, enhancing retrieval monitoring accuracy at test. Consistent with this hypothesis, false recognition was less likely when participants had to search their memory for previous autobiographical elaborations, compared to previous semantic judgments. These false recognition effects were dissociated from true recognition effects across four experiments, implicating a recollection-based monitoring process that was independent from familiarity-based processes. Separately obtained subjective measures provided converging evidence for this conclusion. The cognitive operations engaged during autobiographical elaboration can lead to distinctive recollections, making them less prone to memory distortion than other types of deep or semantic encoding.     

Imagination can create false autobiographical memories

Previous studies have shown that imagining an event can alter autobiographical beliefs. The current study examined whether it can also create false memories. One group of participants imagined a relatively frequent event and received information about an event that never occurs. A second group imagined the nonoccurring event and received information about the frequent event. One week before and again 1 week immediately after the manipulation, participants rated the likelihood that they had experienced each of the two critical events and a series of noncritical events, using the Life Events Inventory. During the last phase, participants were also asked to describe any memories they had for the events. For both events, imagination increased the number of memories reported, as well as beliefs about experiencing the event. These results indicate that imagination can induce false autobiographical memories.     

Are the memories of older adults positively biased?

There is disagreement in the literature about whether a "positivity effect" in memory performance exists in older adults. To assess the generalizability of the effect, the authors examined memory for autobiographical, picture, and word information in a group of younger (17-29 years old) and older (60-84 years old) adults. For the autobiographical memory task, the authors asked participants to produce 4 positive, 4 negative, and 4 neutral recent autobiographical memories and to recall these a week later. For the picture and word tasks, participants studied photos or words of different valences (positive, negative, neutral) and later remembered them on a free-recall test. The authors found significant correlations in memory performance, across task material, for recall of both positive and neutral valence autobiographical events, pictures, and words. When the authors examined accurate memories, they failed to find consistent evidence, across the different types of material, of a positivity effect in either age group. However, the false memory findings offer more consistent support for a positivity effect in older adults. During recall of all 3 types of material, older participants recalled more false positive than false negative memories.     

Liar,liar: Consistent lying decreases belief in the truth

This study investigated the effects of lying on belief ratings for autobiographical childhood events. Participants lied by trying to convince the experimenter that likely events had not happened and that unlikely events had happened. Participants consistently lied, consistently told the truth, and alternated lying and truth telling across two sessions. Results showed that consistent false assents increased belief in those false events and that consistent false denials decreased belief in those true events. False denials had a larger influence on belief than did false assents. False assents that were told first were more likely to increase in belief than were false assents told in the second session. False denials decreased belief in the true event regardless of when they were told. These results suggest that lying influences confidence ratings both by increasing belief in a lied‐about event and by decreasing belief in a true event.     

Ordering the components of autobiographical events

Memory for the temporal order of the components of autobiographical events was examined in two experiments. Experiments 1 and 2 examined the relationship between reaction times to recognise photographs of the components of events and ordering of these photographs. Reaction times were not related to true event position, nor to assigned temporal position, in a manner consistent with an activation strength model of temporal ordering. In contrast, ordering performance was found to be related to event vividness ratings, ability to classify a photograph as one the participant had taken, and retention interval. These findings are all consistent with the hypothesis that the order of an autobiographical event's components is determined by the associative structure that links each component to its general event memory. Overall, memory for the order of the components of autobiographical events may be initially based on associations between the event components and their general event memory representation. These associations appear to decay rapidly leaving only reconstructive ability as the determinant of event component order.     

Judgement of confidence in childhood memories

Memory judgement processes, based on the characteristics and associations of retrieved memories such as sensory details and supporting memories, are considered as important as retrieval in several autobiographical memory models. Judgement processes have received less research attention than memory characteristics themselves. The present studies examined memory judgement using qualitative analysis of the reasons participants gave for confidence in retrieved childhood memories. For memories they were confident of, participants cited memory phenomenology, especially sensory and affective details, much more frequently than consistency with other autobiographical knowledge. For memories they were not confident of, participants reported lack of consistency with autobiographical knowledge or with others' memories more often than memory phenomenology as reasons for their uncertainty. Participants' comments also revealed several metacognitive beliefs about the relationship between memory characteristics and accuracy. These data are consistent with two‐process models of memory judgement associated with true versus false memories. Copyright © 2007 John Wiley & Sons, Ltd.     

Memory for media: investigation of false memories for negatively and positively charged public events

Despite a large body of false memory research, little has addressed the potential influence of an event's emotional content on susceptibility to false recollections. The Paradoxical Negative Emotion (PNE) hypothesis predicts that negative emotion generally facilitates memory but also heightens susceptibility to false memories. Participants were asked whether they could recall 20 "widely publicised" public events (half fictitious) ranging in emotional valence, with or without visual cues. Participants recalled a greater number of true negative events (M=3.31/5) than true positive (M=2.61/5) events. Nearly everyone (95%) came to recall at least one false event (M=2.15 false events recalled). Further, more than twice as many participants recalled any false negative (90%) compared to false positive (41.7%) events. Negative events, in general, were associated with more detailed memories and false negative event memories were more detailed than false positive event memories. Higher dissociation scores were associated with false recollections of negative events, specifically.     

So that's why I don't remember: normalizing forgetting of childhood events influences false autobiographical beliefs but not memories

We investigated changes in autobiographical belief and memory ratings for childhood events, after informing individuals that forgetting childhood events is common. Participants received false prevalence information (indicating that a particular childhood event occurred frequently in the population) plus a rationale normalizing the forgetting of childhood events; false prevalence information alone; or no manipulation, for one (Study 1) or two (Study 2) unlikely childhood events. Results demonstrated that combining prevalence information and the "forgetting rationale" substantially influenced autobiographical belief ratings, whereas prevalence information alone had no impact (Study 1) or a significantly lesser impact (Study 2) on belief ratings. Prevalence information consistently impacted plausibility ratings. No changes in memory ratings were observed. These results provide further support for a nested relationship between judgements of plausibility, belief, and memory in evaluating the occurrence of autobiographical events. Furthermore, the results suggest that some purported false memory phenomena may instead reflect the development of autobiographical false beliefs in the absence of memory.     

So that's why I don't remember: Normalising forgetting of childhood events influences false autobiographical beliefs but not memories

We investigated changes in autobiographical belief and memory ratings for childhood events, after informing individuals that forgetting childhood events is common. Participants received false prevalence information (indicating that a particular childhood event occurred frequently in the population) plus a rationale normalising the forgetting of childhood events; false prevalence information alone; or no manipulation, for one (Study 1) or two (Study 2) unlikely childhood events. Results demonstrated that combining prevalence information and the “forgetting rationale” substantially influenced autobiographical belief ratings, whereas prevalence information alone had no impact (Study 1) or a significantly lesser impact (Study 2) on belief ratings. Prevalence information consistently impacted plausibility ratings. No changes in memory ratings were observed. These results provide further support for a nested relationship between judgements of plausibility, belief, and memory in evaluating the occurrence of autobiographical events. Furthermore, the results suggest that some purported false memory phenomena may instead reflect the development of autobiographical false beliefs in the absence of memory.     

How to accurately detect autobiographical events

ABSTRACT— We describe a new method, based on indirect measures of implicit autobiographical memory, that allows evaluation of which of two contrasting autobiographical events (e.g., crimes) is true for a given individual. Participants were requested to classify sentences describing possible autobiographical events by pressing one of two response keys. Responses were faster when sentences related to truly autobiographical events shared the same response key with other sentences reporting true events and slower when sentences related to truly autobiographical events shared the same response key with sentences reporting false events. This method has possible application in forensic settings and as a lie-detection technique.     

Personalized and not general suggestion produces false autobiographical memories and suggestion-consistent behavior

Suggesting false childhood events produces false autobiographical beliefs, memories and suggestion-consistent behavior. The mechanisms by which suggestion affects behavior are not understood, and whether false beliefs and memories are necessary for suggestions to impact behavior remains unexplored. We examined the relative effects of providing a personalized suggestion (suggesting that an event occurred to the person in the past), and/or a general suggestion (suggesting that an event happened to others in the past). Participants (N=122) received a personalized suggestion, a general suggestion, both or neither, about childhood illness due to spoiled peach yogurt. The personalized suggestion resulted in false beliefs, false memories, and suggestion-consistent behavioral intentions immediately after the suggestion. One week or one month later participants completed a taste test that involved eating varieties of crackers and yogurts. The personalized suggestion led to reduced consumption of only peach yogurt, and those who reported a false memory showed the most eating suppression. This effect on behavior was equally strong after one week and one month, showing a long lived influence of the personalized suggestion. The general suggestion showed no effects. Suggestions that convey personal information about a past event produce false autobiographical memories, which in turn impact behavior.