Brief Exposure to Misinformation Can Lead to Long‐Term False Memories

Do false memories last? And do they last as long as true ones? This study investigated whether experimentally created false memories would persist for an extended period (one and a half years). A large number of subjects (N = 342) participated in a standard three‐stage misinformation procedure (saw the event slides, read the narrations with misinformation, and then took the memory tests). The initial tests showed that misinformation led to a significant amount of false memory. One and a half years later, the participants were tested again. About half of the misinformation false memory persisted, which was the same rate as for true memory. These results strongly suggest that brief exposure to misinformation can lead to long‐term false memory and that the strength of memory trace was similar for true and false memories. Copyright © 2011 John Wiley & Sons, Ltd.     

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.     

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.     

Treat and trick: A new way to increase false memory

This paper reports a new experimental manipulation that increased false memories 1 month after the manipulation. Mirroring the standard three‐stage misinformation paradigm (original event, misinformation, and test), subjects in the experimental group were first given a colour‐slide presentation of two stories (events), then given an accurate account (instead of misinformation) of the events in narrations, and finally tested for their memory of the original events. One month later, they underwent the standard misinformation paradigm with two new events. The comparison group was given the standard misinformation tasks at both time points. Results showed that the experimental group produced more false memories in the subsequent misinformation paradigm than did the comparison group. We focus on trust and credibility as possible mechanisms underlying this effect. Copyright © 2009 John Wiley & Sons, Ltd.     

The relationship between DRM and misinformation false memories

This research investigated the relationship between false memories induced by two different paradigms (misinformation and Deese–Roediger–McDermott [DRM]). The misinformation effect refers to the phenomenon that a person’s recollection of a witnessed event can be altered after exposure to misleading information about the event. DRM false memory represents the intrusion of words that are semantically related but not actually presented in the study session. Subjects (N = 432) completed both misinformation and DRM false memory tests. Results showed a small but significant correlation (r = .12, p = .02) between the misinformation and DRM false memories. Furthermore, using signal detection theory, we found that the discrimination ability index (d′) was related to both the misinformation and DRM false memories (r = ?.12 and ?.13, p = .01), while the response bias was related only to DRM false memory (r = ?.46, p < .001). These results suggest that misinformation and DRM false memories generally involve different mechanisms and that their shared mechanism may involve the global discrimination ability.     

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.     

The misinformation effect is unrelated to the DRM effect with and without a DRM warning

The misinformation and Deese–Roediger–McDermott (DRM) paradigms are used to study forms of false memories. Despite the abundance of research using these two paradigms, few studies have examined the relationship between the errors that arise from them. In the present study, 160 participants completed a misinformation task and two DRM tasks, receiving a warning about the effect before the second DRM task. Participants demonstrated misinformation and DRM effects (with and without the warning), but susceptibility to these forms of false memory were not significantly related across individuals. The DRM warning reduced the DRM effect, and signal detection analysis revealed that the DRM warning reduced a liberal response bias in this task. Sensitivity and response bias in both DRM tasks were not significantly related to these measures in the misinformation task. These findings suggest that these two forms of false memories are not interchangeable and they appear to be the result of different cognitive processes.     

错误记忆研究范式评介

文章概括评介了当前错误记忆研究的几种主要范式及其各自可能的认知机制。联想研究范式(包括集中联想研究范式与类别联想研究范式)和无意识知觉范式描述了人们对单词的错误记忆,而误导信息干扰范式和KK研究范式则描述了人们对持续事件的错误记忆。这两类不同的研究范式证实了可能存在不同类型的错误记忆,且可能具有不同的认知加工机制。它们都从一定层面上揭示了错误记忆现象的本质和特征,并为人们进行更深入的研究提供了有效的方法。     

Overgeneral autobiographical memory recollection in Iranian combat veterans with posttraumatic stress disorder

This study examined the recollection of autobiographical material in memory among Iranian military veterans with and without posttraumatic stress disorder (PTSD), and healthy non-trauma-exposed control subjects. Participants completed the Autobiographical Memory Test, Autobiographical Memory Interview (counterbalanced), Impact of Event Scale-Revised, Beck Depression Inventory-II, Wechsler Memory Scale-III and Wechsler Adult Intelligence Scale-Revised. The PTSD group generated fewer specific episodic and semantic details of autobiographical memory compared to the non-PTSD and control groups. Working memory did not significantly moderate the relationship between PTSD diagnosis and reduced autobiographical memory specificity but did moderate the relationship between PTSD diagnosis and semantic recall; semantic memory recall was not significantly related to working memory ability for those with PTSD but was related to working memory ability for trauma survivors without PTSD. While the data provide some support for the expectation that higher working memory ability is associated with an increased ability to retrieve specific memories (i.e. semantic memory recall in those without PTSD), the findings are also consistent with the view that for those with PTSD the demands on working memory required for affect regulation cancel out this influence of working memory in augmenting access to specific memories.     

Neural activity during encoding predicts false memories created by misinformation

False memories are often demonstrated using the misinformation paradigm, in which a person's recollection of a witnessed event is altered after exposure to misinformation about the event. The neural basis of this phenomenon, however, remains unknown. We used fMRI to investigate encoding processes during the viewing of an event and misinformation to see whether neural activity during either encoding phase could predict what would be remembered. fMRI data were collected as participants studied eight vignettes (Original Event phase). Shortly afterward, participants studied the same vignettes during scanning, but with changes to several details, serving as the misinformation (Misinformation phase). Two days later, their memories for the Original Event were assessed. Activity that subsequently led to true and false memories was examined during both encoding phases. Two interaction patterns between encoding phase (Original Event and Misinformation) and type of memory (true and false) were observed in MTL and PFC regions. In the left hippocampus tail and perirhinal cortex, a predictive item-encoding pattern was observed. During the Original Event phase, activity was greater for true than false memories, whereas during the Misinformation phase, activity was greater for false than true memories. In other regions, a pattern suggestive of source encoding was observed, in which activity for false memories was greater during the Original Event phase than the Misinformation phase. Together, these results suggest that encoding processes play a critical role in determining true and false memory outcome in misinformation paradigms.     

Cortisol response and psychological distress predict susceptibility to false memories for a trauma film

For eyewitness testimony to be considered reliable, it is important to ensure memory remains accurate following the event. As many testimonies involve traumatic, as opposed to neutral, events, it is important to consider the role of distress in susceptibility to false memories. The aim of this study was to investigate whether cortisol response following a stressor would be associated with susceptibility to false memories. Psychological distress responses were also investigated, specifically, dissociation, intrusions, and avoidance. Participants were allocated to one of three conditions: those who viewed a neutral film (N?=?35), those who viewed a real trauma film (N?=?35), and a trauma “reappraisal” group where participants were told the film was not real (N?=?35). All received misinformation about the film in the form of a narrative. Participants provided saliva samples (to assess cortisol) and completed distress and memory questionnaires. Cortisol response was a significant predictor of the misinformation effect. Dissociation and avoidance were related to confabulations. In conclusion, following a stressor an individual may differ with regard to their psychological response to the event, and also whether they experience a cortisol increase. This may affect whether they are more distressed later on, and also whether they remember the event accurately.     

Self-relevance enhances susceptibility to false memory

Eyewitness testimony serves as important evidence in the legal system. Eyewitnesses of a crime can be either the victims themselves—for whom the experience is highly self-referential—or can be bystanders who witness and thus encode the crime in relation to others. There is a gap in past research investigating whether processing information in relation to oneself versus others would later impact people's suggestibility to misleading information. In two experiments (Ns = 68 and 122) with Dutch and Chinese samples, we assessed whether self-reference of a crime event (i.e., victim vs. bystander) affected their susceptibility to false memory creation. Using a misinformation procedure, we photoshopped half of the participants' photographs into a crime slideshow so that they saw themselves as victims of a nonviolent crime, while others watched the slideshow as mock bystander witnesses. In both experiments, participants displayed a self-enhanced suggestibility effect: Participants who viewed themselves as victims created more false memories after receiving misinformation than those who witnessed the same crime as bystanders. These findings suggest that self-reference might constitute a hitherto new risk factor in the formation of false memories when evaluating eyewitness memory reports.     

Prime time news: The influence of primed positive and negative emotion on susceptibility to false memories

We examined the relation between emotion and susceptibility to misinformation using a novel paradigm, the ambiguous stimuli affective priming (ASAP) paradigm. Participants (N = 88) viewed ambiguous neutral images primed either at encoding or retrieval to be interpreted as either highly positive or negative (or neutral/not primed). After viewing the images, they either were asked misleading or non-leading questions. Following a delay, memory accuracy for the original images was assessed. Results indicated that any emotional priming at encoding led to a higher susceptibility to misinformation relative to priming at recall. In particular, inducing a negative interpretation of the image at encoding led to an increased susceptibility of false memories for major misinformation (an entire object not actually present in the scene). In contrast, this pattern was reversed when priming was used at recall; a negative reinterpretation of the image decreased memory distortion relative to unprimed images. These findings suggest that, with precise experimental control, the experience of emotion at event encoding, in particular, is implicated in false memory susceptibility.     

Forced fabrication versus interviewer suggestions: Differences in false memory depend on how memory is assessed

Many studies show that witnesses can develop false memories for suggested misinformation provided by an interviewer. The forced fabrication effect extends this finding by demonstrating that witnesses can also develop false memories for events they were forced to fabricate themselves. In two experiments we compared the incidence of false memory following forced fabrication and interviewer provided suggestion under various conditions (pre‐test warning/no warning; one‐week/two‐week delay) and type of test (source recognition vs. narrative recall). Whereas interviewer suggestions resulted in more false memories than forced fabrications on source recognition tests when participants overtly resisted fabricating and were warned at test, tests of narrative recall showed the opposite pattern even with pre‐test warnings: Fabrications generated following overt resistance led to more false recall than interviewer provided suggestions. This dissociation between suggestive interview type and test type indicates that predictions about the deleterious consequences of interviews are dependent on the way memory is assessed. Copyright © 2011 John Wiley & Sons, Ltd.     

错误信息效应的主要理论与影响因素的述评与展望

个体对原始信息的记忆受到随后错误信息的影响而产生错误记忆被称为错误信息效应.通过对新近研究的梳理与归纳,发现错误信息效应的研究热点集中于解释效应产生机制的理论研究以及效应的影响因素研究.因此,本文重点归纳和述评了错误信息效应的五种理论和三类影响因素.未来的研究建议从以下几方面开展:第一,错误信息产生机制和理论研究;第二...     

Aging and the misinformation effect: a neuropsychological analysis

Older adults' susceptibility to misinformation in an eyewitness memory paradigm was examined in two experiments. Experiment 1 showed that older adults are more susceptible to interfering misinformation than are younger adults on two different tests (old-new recognition and source monitoring). Experiment 2 examined the extent to which processes associated with frontal lobe functioning underlie older adults' source-monitoring difficulties. Older adults with lower frontal-lobe-functioning scores on neuropsychological tests were particularly susceptible to false memories in the misinformation paradigm. The authors' results agree with data from other false memory paradigms that show greater false recollections in older adults, especially in those who scored poorly on frontal tests. The results support a source-monitoring account of aging and illusory recollection.     

Reinstatement of odour context cues veridical memories but not false memories

ABSTRACT

The sense of smell has made a recent return to the forefront of research on episodic memory. Odour context cues can reactivate recently encoded memories during sleep-dependent memory consolidation [e.g., Rasch, B., Buchel, C., Gais, S., & Born, J. (2007). Odor cues during slow-wave sleep prompt declarative memory consolidation. Science, 315, 1426–1429], and reinstating the odour experienced during encoding at test results in superior recall and recognition [e.g., Isarida, T., Sakai, T., Kubota, T., Koga, M., Katayama, Y., & Isarida, T. K. (2014). Odor-context effects in free recall after a short retention interval: A new methodology for controlling adaptation. Memory & Cognition, 42, 421–433]. However, whether the impact of odour cues is restricted to the specific memories studied in the presence of the odour, or whether reinstating the odour also cues unstudied memories that are semantically related to the studied memories (i.e., false memories) is unknown. We used the Deese-Roediger-McDermott false memory paradigm to quantify the impact of odour cues on both veridical memory and false memory. Reinstating the odour presented during the study of the DRM word lists at the test phase resulted in better free recall of the studied words, but had no statistically significant impact on the number of false memories produced. We argue that odour cues influence recall of the memories they co-occurred with during study but potentially not semantically related memories.     

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.     

Not lost in translation: writing auditorily presented words at study increases correct recognition “at no cost”

Previous studies have reported a translation effect in memory, whereby encoding tasks that involve translating between processing domains produce a memory advantage relative to tasks that involve a single domain. We investigated the effects of translation on true and false memories using the Deese/Roediger-McDermott (DRM) procedure [Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58, 17–22; Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, & Cognition, 21, 803–814]. Translation between modalities enhanced correct recognition but had no effect on false recognition. Results are consistent with previous research showing that correct memory can be enhanced “at no cost” in terms of accuracy. Findings are discussed in terms of understanding the relationship between true and false memories produced by the DRM procedure.     

Is saccade-induced retrieval enhancement a potential means of improving eyewitness evidence?

Saccade-induced retrieval enhancement (SIRE) is the effect whereby making bilateral saccades enhances the subsequent retrieval of memories. Two experiments explored SIRE's potential to improve eyewitness evidence. Participants viewed slideshows depicting crimes, and received contradictory and additive misinformation about event details either once (Experiment 1) or three times (Experiment 2). Participants then performed saccades or a fixation control task before being tested on their memory for the slideshows and making confidence judgements. Saccades increased discrimination between seen and unseen event details regardless of whether or what type of misinformation was presented. Because prior studies indicated that SIRE might be more robust for individuals who are strongly right-handed versus not, we examined SIRE as a function of handedness and found that saccades improved memory for event details regardless of participants' handedness. However, participants who were not strongly right-handed had fewer false memories than participants who were strongly right-handed, extending previous findings of superior memory among individuals who are not strongly right-handed. Saccades also increased confidence in true memories (Experiment 1) and decreased confidence in false memories (Experiment 2). The results support SIRE's potential to improve eyewitness evidence.