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Amalgamations of Memories: Intrusion of Information from One Event into Reports of Another
Abstract
SUMMARY Numerous researchers have reported that exposure to misleading postevent information (MPI) regarding details in a witnessed event can lead people to report false details from the MPI when asked to report the witnessed event. In such studies, the MPI is presented to participants in the context of information about the witnessed event. This experiment tests the hypothesis that postevent exposure to information that participants know is not about the witnessed event can, nonetheless, aÄect performance on tests of memory for that event. As predicted, when asked to report details of an event depicted in a slide show, participants tended to intrude details mentioned in a recent postevent narrative that described a diÄerent event. #1998 John Wiley & Sons, Ltd.
... when there was no barn). Allen and Lindsay (1998), however, found that participants sometimes intruded details from a verbal description of one event into their memory reports of a different event. ...
... One reason for interest in the misinformation effect is that it may generalize to real-world cases in which eyewitnesses are asked questions about a consequential event. To the extent such effects do generalize, the Allen and Lindsay (1998) findings raise the possibility that eyewitnessesÕ testimony may be compromised not only by suggestions regarding the witnessed event but also by memories of other events. Such information might come from a variety of sources (e.g., TV, books, other personal or vicarious experiences). ...
... The current paper has two major aims. First, we sought to replicate the findings of the Allen and Lindsay (1998) experiment (which is the only extant demonstration of intrusions from a narrative description of one event into eyewitness reports of another event) with a variety of materials. Second, we assessed the role of the degree of conceptual similarity between the witnessed event and the narrative in modulating the rate of such intrusions. ...
We explored the effect of the degree of conceptual similarity between a witnessed event and an extra-event narrative on eyewitness suggestibility. Experiments 1A and 1B replicated Allen and LindsayÕs (1998) finding that subjects sometimes intrude details from a narrative description of one event into their reports of a different visual event. Those experiments also showed that intrusion rates were even higher when the narrative described the visual event itself. Experiment 2 replicated those findings, but found no more intrusions from a thematically similar versus dissimilar narrative. In Experiment 3 we disguised the relationship between the narrative and visual event, and obtained more intrusions from a thematically similar than dissimilar narrative. In Experiment 4 we obtained a thematic similarity effect when the relationship between narrative and visual event was disguised, but none when it was not. Results are discussed from the perspective of the source-monitoring framework.
... When people are provided with misleading information about an event it may cause a memory alteration of that event. This phenomenon is called the misinformation effect and it can distort the memory of an event (Allen & Lindsay, 1998;Loftus, 1979Loftus, , 2003Zaragoza & Lane, 1994). People can even include misinformation into the details of the experienced event from details belonging to a misinformation event in spite of the fact that they are aware that the two events are different. ...
... People can even include misinformation into the details of the experienced event from details belonging to a misinformation event in spite of the fact that they are aware that the two events are different. For example, Allen and Lindsay (1998) found that participants included details from the irrelevant post-event narrative into the memory of the details of the stimulus event. This makes it even more relevant in forensic situations to know which kind of information is more vulnerable to misinformation. ...
... Effet de la similitude des épisodes 1 et 2 : cet effet se réfère à la proximité entre l'événement d'étude et l'événement perturbateur, similitude qui peut concerner la proximité sémantique et/ou perceptive (Allen & Lindsay, 1998 ;Lindsay, Allen, Chan & Dahl, 2004). Ces auteurs ont montré que les confusions de source sont plus fréquentes dans les situations expérimentales où les deux épisodes ont de nombreuses caractéristiques en commun (des détails, des objets qui sont cités dans les deux situations) comparé aux situations où les deux épisodes sont bien distincts et partagent peu de caractéristiques. ...
Résumé Depuis une dizaine d’années, l’étude des faux souvenirs, comme les fausses reconnaissances (FR), a suscité une abondance de travaux compartimentée en différents champs d’investigation, et notamment selon le type de méthode utilisée pour les induire. Nous proposons ici une revue de questions incluant les hypothèses explicatives et les données actuelles, qui s’étend à deux formes de FR, à savoir les FR associatives (confusion entre des informations perçues vs . imaginées) et les FR de source (confusion entre deux événements réellement vécus). Pour les FR associatives, induites notamment avec le paradigme DRM, les études ont conduit à la mise en évidence de deux principaux mécanismes : les mécanismes d’activation implicite à l’encodage et les mécanismes post-récupération de contrôle de la source ( i.e. hypothèse à double processus, Roediger, Balota, et Watson, 2001a). Pour les FR de source, induites avec le paradigme MI, les études suggèrent également que deux mécanismes soient identifiés : les mécanismes de mémoire de source et ceux du contrôle de la source post-récupération ( i.e. théorie du contrôle de la source, Johnson, Hashtroudi & Lindsay, 1993). En s’appuyant sur la théorie du contrôle de la source comme cadre d’analyse commun, l’examen détaillé de ces deux formes de FR permet de mettre en lumière les différences et les similitudes entre ces deux formes de faux souvenirs.
... It has been found that the processes that lead to accurate memory attributions can also produce false memories. This is especially the case when the mental representation of real and false events share similar characteristics and inappropriate criteria and heuristics are employed to evaluate recalled details (e.g., Allen & Lindsay, 1998;Lindsay, Johnson, & Kwon, 1991;Lyle & Johnson, 2007). In such instances, a mental representation might be incorrectly attributed to the past with the result being a false autobiographical memory. ...
Research has demonstrated that merely imagining an autobiographical event can bring about false memories for that event. One explanation for this is that imagination leads to the creation and incorporation of visual-imagistic information into the event representation. This idea was tested in two experiments in which visual-imagery processing was disrupted by the use of Dynamic Visual Noise (DVN). In Experiment 1, autobiographical memories that were rated as “known” and lacking in event detail were subsequently rated as more “remembered” following imagination. In Experiment 2, imagination led to improbable autobiographical events being rated as more believable and vivid. In both experiments, interfering with imagery processing by DVN reduced these effects. It was concluded that visual-imagistic processing plays an important role in altering the mnemonic status of autobiographical representations.
... Effet de la similitude des épisodes 1 et 2 : cet effet se réfère à la proximité entre l'événement d'étude et l'événement perturbateur, similitude qui peut concerner la proximité sémantique et/ou perceptive (Allen & Lindsay, 1998 ;Lindsay, Allen, Chan & Dahl, 2004). Ces auteurs ont montré que les confusions de source sont plus fréquentes dans les situations expérimentales où les deux épisodes ont de nombreuses caractéristiques en commun (des détails, des objets qui sont cités dans les deux situations) comparé aux situations où les deux épisodes sont bien distincts et partagent peu de caractéristiques. ...
During the past decade, research on false memories, as the false recognitions (FR), has exploded. However, the large data is currently segmented according to the experimental techniques used to elicit FR. The present work proposed an theoretical and empirical overview for two paradigms inducing FR: 1. the DRM paradigm or derived tasks inducing the associative FR that refer to FR of lures that are strongly related to item really studied, and 2. the MI paradigm inducing the source FR where lures from a real event are recognized as belonging to another one. For the former, there is a body of evidence of two main origin mechanisms: the implicit associative activation processes and the failure of source monitoring processes in the post-retrieval phase (i.e., dual-process hypothesis, Roediger, Balota and Watson, 2001a). For the latter, the failure of two main mechanisms is also identified such as the source memory and the source monitoring mechanisms (i.e. Source Monitoring Framework from Johnson, Hashtroudi and Lindsay, 1993). From the overall data relative to these two kinds of FR, similarities and differences are highlighted in terms of processes involved according to the Source Monitoring Framework.
... The expectation in such a situation is that you should be able to accurately recall the details of the crime, and only those details. Prior research has found that such situations involve quite a difficult memory task and that errors may often result (e.g., Allen & Lindsay, 1998;Lane & Zaragoza, 2007;Lane, Mather, Villa, & Morita, 2001;Lindsay, 1993;Lindsay, Allen, Chan, & Dahl, 2003;Loftus, Miller, & Burns, 1978;Zaragoza & Lane, 1994). In some circumstances, real-life witness errors may be highly consequential as evidenced by numerous false convictions that have been documented as a result of DNA exonerations (Scheck, Neufeld, & Dwyer, 2000). ...
... One reason is because we are "essentially sense-making beings and tend to create explanations" (Gass & Mackey, 2000, p.6), such as filling in omissions that were not present because they are typical of that situation (Hannigan & Reinitz, 2001;Waldmann, Holyoak, & Fratianne, 1995). This weakness has been well documented, especially the way in which details from one event or context intrude upon, and are incorporated into, memories of a completely different event and, consequently, result in erroneous data (Allen & Lindsay, 1998;Hannigan & Reinitz, 2003;Lindsay, Allen, Chan, & Dahl, 2004). ...
Stimulated recall is an empirically rigorous introspection data collection tool that allows the interviewer to elicit, identify and explore participants’ thinking. In this study it was used to identify the types of thinking skills and strategies employed by first year university students engaged in a Chinese language and culture lesson in Second Life. A valuable affordance of this technique is the ability to account for stimuli from both the virtual and physical environments, thus strengthening the researchers’ claims about the relationship between thinking and instructional design. This was accomplished through the use of screen capture software to record both the avatar’s on-screen activity in Second Life as well as the face of the participant (via the web camera). This data was then used during the interview, within strict methodological protocols, to stimulate participants’ recall of their thinking at the time of doing the activity. The value of stimulated recall over other introspection tools, within the context of this study, is discussed. In addition, methodological concerns, especially those relating to reliability and validity of data, are outlined in this article and data from the study is used to explicate strategies to minimize those concerns.
... Perhaps even more surprising than the social-contagion effects is the recent finding that participants will sometimes intrude details from one event into their memory of a different event (Allen & Lindsay, 1998;Lindsay, Allen, Chan, & Dahl, 2004). ...
... This phenomenon is called the "misinformation effect" and it can distort the memory of some certain event (Loftus, 1979). People can even include such information into their reports which they know does not belong to that event (Allen & Lindsay, 1998). This makes it even more important in forensic situations to know which kind of information is more vulnerable to misinformation. ...
... Importantly, however, when conditions are such that it is difficult for subjects to differentiate between memories of the witnessed event versus memories of the postevent information, then subjects sometimes genuinely confuse memories from the latter source as memories of the witnessed event itself (for a review, see Lindsay, 1994). It is worth noting that intrusions of memories from one source into reports of another can occur even when subjects are explicitly warned against making such errors (e.g., Lindsay, 1990), even when the source in which the suggestions were embedded pertained to a different event from the witnessed event (e.g., Allen & Lindsay, 1998), and even when the suggestions preceded rather than followed the witnessed event (Lindsay, Allen, Chan, & Dahl, 2004). ...
Dans la première partie de cet article, je résume la perspective du monitorage de la source des souvenirs sur les processus cognitifs impliqués dans la différenciation entre les évènements mentaux de diverses sources (par ex., les souvenirs d’un crime qu’une personne conserve par rapport à ce qu’elle a entendu plus tard dans la description d’un autre témoin). Dans la deuxième partie de cet article, j’examine selon la perspective du cadre du monitorage de la source, quatre questions relatives aux rappels des souvenirs lors de situations judiciaires : 1) le rapport des souvenirs des adultes, 2) les rapports des souvenirs des enfants, 3) les « souvenirs retrouvés » d’abus sexuel au cours de l’enfance et 4) les décisions des témoins relativement à l’identification du suspect. Finalement, je commente brièvement le rôle des psychologues en recherche en tant que témoins experts avant de présenter mes conclusions.
... In misinformation research, possibly complex underlying memory constellations (e.g. two remembered relevant details, without recollection of their sources) are often forced into the Procrustean bed of a simple forced choice between two alternatives, typically resulting in performance losses in the misled compared to the control condition of misinformation – or more generally memory interference – designs (Blank, 2005). For this reason alone (i.e., even in the absence of other factors such as consistency assumptions), poor source memory/ discrimination will lead to a misinformation effect (Allen & Lindsay, 1998; Lindsay, Allen, Chan, & Dahl, 2004; Exp. 3 of the current study) and improving source discrimination will reduce it (English & Nielson, 2010; Parker et al., 2008). Before this background, we consider the memory state test used in Experiments 1 and 3 to be the best currently available match between the possible range of underlying memory states and available response options in the test, and therefore the best 'window' into participants' underlying memories (see Blank, 1998; Blank, 2005, for detailed discussions). ...
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.
... Likewise, a key prediction of the source monitoring theory is that any manipulation that increases the extent to which memories from one source resemble those from another increases the likelihood of source misattribution. In support of this prediction, Allen and Lindsay (1998) found that source misattributions were more common for details that were similar between the original event and postevent information than for details that were quite different between the two. For example, if participants were shown a 'Pepsi' can in the original slide show and then a 'Coke' can in a subsequent show, participants would often report that the 'Coke' can was in the original show because the two soft drinks are quite similar. ...
... Since the mid-70s, a plethora of research has demonstrated that postevent misinformation may change reported details of an event that an individual has witnessed or even cause individuals to report people or objects that were never experienced (e.g. Allen & Lindsay, 1998;Belli, 1989;Chandler, Gargano, & Holt, 2001;Henkel, Franklin, & Johnson, 2000;Lindsay, 1990;Lindsay, Allen, Chan, & Dahl, 2004;Lindsay, Hagen, Wade, & Garry, 2004;Loftus, 1975Loftus, , 1979Loftus & Hoffman, 1989;Loftus, Miller, & Burns, 1978;Loftus & Palmer, 1974;Lyle & Johnson, 2006;Marche, Brainerd, & Reyna, 2010;Mitchell & Zaragoza, 1996, 2001Okado & Stark, 2005;Skagerberg & Wright, 2008;Stark, Okado, & Loftus, 2010;Sutherland & Hayne, 2001;Wright & Loftus, 1998;Wright, Self, & Justice, 2000). ...
The misinformation effect is a term used in the cognitive psychological literature to describe both experimental and real-world instances in which misleading information is incorporated into an account of an historical event. In many real-world situations, it is not possible to identify a distinct source of misinformation, and it appears that the witness may have inferred a false memory by integrating information from a variety of sources. In a stimulus equivalence task, a small number of trained relations between some members of a class of arbitrary stimuli result in a large number of untrained, or emergent relations, between all members of the class. Misleading information was introduced into a simple memory task between a learning phase and a recognition test by means of a match-to-sample stimulus equivalence task that included both stimuli from the original learning task and novel stimuli. At the recognition test, participants given equivalence training were more likely to misidentify patterns than those who were not given such training. The misinformation effect was distinct from the effects of prior stimulus exposure, or partial stimulus control. In summary, stimulus equivalence processes may underlie some real-world manifestations of the misinformation effect.
... During the delay between witnessing a crime and providing testimony, witnesses are often questioned by police investigators, lawyers, friends, and family members (Gray, 1993;Whitcomb, Shapiro, & Stellwagen, 1985). Moreover, during this delay, eyewitnesses can encounter misleading information from various sources (Allen & Lindsay, 1998;Lindsay, Allen, Chan, & Dahl, 2004). It is well known that misinformation can degrade the accuracy of later eyewitness reports (for a recent review, see Zaragoza, Belli, & Payment, 2007). ...
Eyewitnesses typically recount their experiences many times before trial. Such repeated retrieval can enhance memory retention of the witnessed event. However, recent studies (e.g., Chan, Thomas, & Bulevich, 2009) have found that initial retrieval can exacerbate eyewitness suggestibility to later misleading information--a finding termed retrieval-enhanced suggestibility (RES). Here we examined the influence of multiple retrieval attempts on eyewitness suggestibility to subsequent misinformation. In four experiments, we systematically varied the number of initial tests taken (between zero and six), the delay between initial testing and misinformation exposure (~30 min or 1 week), and whether initial testing was manipulated between- or within-subjects. University undergraduate students were used as participants. Overall, we found that eyewitness suggestibility increased as the number of initial tests increased, but this RES effect was qualified by the delay and by whether initial testing occurred in a within- or between-subjects manner. Specifically, the within-subjects RES effect was smaller than the between-subjects RES effect, possibly because of the influence of retrieval-induced forgetting/facilitation (Chan, 2009) when initial testing was manipulated within subjects. Moreover, consistent with the testing effect literature (Roediger & Karpicke, 2006), the benefits of repeated testing on later memory were stronger after a 1-week delay than after a 30-min delay, thus reducing the negative impact of RES in long-term situations. These findings suggest that conditions that are likely to occur in criminal investigations can either increase (repeated testing) or reduce (delay) the influence of RES, thus further demonstrating the complex relationship between eyewitness memory and repeated retrieval.
... Quellenkonfusionen entstehen können. Für diese Hypothese spricht, dass Falschinformationseffekte umso schwächer werden, je leichter verschiedene Informationsquellen unterscheidbar sind (Allen & Lindsay, 1998;Lindsay, 1990 Zwei Vorhersagen lassen sich aus dieser Gleichung herleiten. Erstens, verändert man den Gedächtnistest so, dass die Ratewahrscheinlichkeit b den Wert 0,5 annimmt, dann muss der Falschinformationseffekt verschwinden. ...
Die Gedächtnispsychologie des Augenzeugen hat eine Reihe von Bedingungen identifiziert, unter denen Zeugenaussagen mit Skepsis betrachtet werden müssen. Als problematisch erweisen sich in erster Linie automatische, schemagesteuerte Rekonstruktionsprozesse bei nicht abrufbarem Faktengedächtnis. Auf der anderen Seite kann die Gedächtnisrepräsentation eines Ereignisses aber auch sehr robust gegenüber verschiedenen Einflussfaktoren sein. Dieser Artikel stellt Determinanten verzerrter Gedächtnisurteile vor. Ferner werden Methoden der Diagnose und der Optimierung von Qualität und Umfang einer Zeugenaussage diskutiert.
... Prior research has shown that exposure to related material between the original event and a memory test may produce errors. This occurs when the exposure is incidental (e.g., Allen & Lindsay, 1998; Gerkens, Pierce, & Smith, unpublished manuscript), or presented within the context of the original event (e.g., Loftus, Miller, & Burns, 1978; Mitchell & Zaragoza, 1996; Zaragoza & Lane, 1994). Findings of studies like those listed above have already brought considerable scrutiny of eyewitness testimony. ...
Research in our laboratory has demonstrated blocked and recovered memories within the context of a controlled experiment. The comparative memory paradigm allows for comparisons of recovered memories, continuous memories, and false memories. Additional research in our laboratory has shown two distinct types of memory errors; semantic based errors which occur due to pre-existing category knowledge, and episodic based errors in which the source of details (list members) are misattributed. Independently, these two lines of research have illuminated basic memory processes, however, they have not been combined previously. That is, the experiments in the present study explore the susceptibility of recovered memories to semantic and episodic based errors relative to continuous memories. Experiment 1 replicated the large blocking and recovery effects previously found by our laboratory. Additionally, it demonstrated that recovered memories were no more prone to semantic based errors than were continuous memories. These errors occurred very infrequently despite the use of materials chosen specifically to induce such errors. Experiment 2 again replicated the large blocking and recovery effects. The equivalent low rate of semantic based errors was also replicated. However, Experiment 2 also revealed that recovered memories were more susceptible to episodic based errors than were continuous memories. This was especially true when the memory block occurred in an interference treatment condition. Finally, post-recall source recognition tests failed to improve memory accuracy. In fact, numerically both semantic based and episodic based errors increased on the source recognition test relative to the cued recall test. Findings are discussed in relation to the source monitoring and fuzzy-trace theories of memory as well as the legal and clinical recovered memory controversy.
The tendency to confuse witnessed and suggested information can result in inaccurate eyewitness testimonies and convictions of innocent people. Studies that tested how similarities between witnessed and suggested information affect the tendency to confuse them reached inconsistent results. Here, we claim that there is a more complex and not necessarily linear relationship between similarity and memory distortions. Participants (164) viewed two subsequent stories, which varied in the conceptual and perceptual similarities between them. We found a significant interaction between conceptual and perceptual similarities. When we presented two conceptually different stories, perceptual similarity increased the suggestibility effect compared with perceptual dissimilarity. Conversely, when we presented two conceptually similar stories, perceptual similarity decreased suggestibility compared with perceptual dissimilarity. Accordingly, we suggest that similarity between two events may increase the suggestibility effect. However, counter-intuitively, once similarity reaches a certain threshold, the coherence level between the events reduces the tendency to confuse them. Copyright © 2014 John Wiley & Sons, Ltd.
During the past decade, research on false memories, as the false recognitions (FR), has exploded. However, the large data is currently segmented according to the experimental techniques used to elicit FR. The present work proposed an theoretical and empirical overview for two paradigms inducing FR: 1. the DRM paradigm or derived tasks inducing the associative FR that refer to FR of lures that are strongly related to item really studied, and 2. the MI paradigm inducing the source FR where lures from a real event are recognized as belonging to another one. For the former, there is a body of evidence of two main origin mechanisms: the implicit associative activation processes and the failure of source monitoring processes in the post-retrieval phase (i.e., dual-process hypothesis, Roediger, Balota and Watson, 2001a). For the latter, the failure of two main mechanisms is also identified such as the source memory and the source monitoring mechanisms (i.e. Source Monitoring Framework from Johnson, Hashtroudi and Lindsay, 1993). From the overall data relative to these two kinds of FR, similarities and differences are highlighted in terms of processes involved according to the Source Monitoring Framework.
Uses the alleged sighting of John Doe 2 to examine possible errors of eyewitness identification in the trials of Timothy McVeigh and Terry Nichols in the 1995 Oklahoma City bombing. The authors show how, in such a high-profile case, eyewitness accounts may be especially vulnerable to distortion (see A. Memon et al, 1998; D. B. Wright and G. M. Davies, 1999, for more extensive reviews of eyewitness testimony). Extracts from the testimony of Gary Wells, an international authority on eyewitness identification, are used to illustrate questions of interest to lawyers and misconceptions about eyewitness abilities. The article focuses on reports of John Doe 2, when allegedly seen, with McVeigh, at Elliott's body shop two days before the explosion (17 April), and asks what can eyewitness research tell about the accuracy of V. Beemer, T. Kessinger, and E. Elliott's recollections? Research on the confidence and accuracy of eyewitnesses, cross-contamination of eyewitnesses, repeated recall attempts of eyewitnesses, and reliability of eyewitness descriptions is discussed. It is concluded that, given the imperfections of memory, it may never be known for certain whether John Doe 2 played a part in what has come to be known as the most bloody mass murder in American history. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
The aim of the present study was to create the conditions of real discussion concerning the past in an experimental setting and examine their effect on subsequent recollections of autobiographical events. Sixty first-year Jagiellonian University students described two important autobiographical events twice. In between the two recall sessions, participants from the experimental group viewed two films. The first was a short televised account of the two events; the second was a corresponding videotaped description of the personal experiences of a young woman. In addition, participants were asked to imagine what she had been talking about. Most of the participants from the experimental group incorporated elements of the woman's description into their own subsequent accounts. In spite of this, they rated the vividness and the accuracy of their posttest memories as very high. The results are discussed in terms of source misattribution as a distortion mechanism in episodic memory. Copyright © 2002 John Wiley & Sons, Ltd.
We compared young and older adults' source monitoring performance on an explicit source identification test using the misinformation paradigm. Several age-related differences in source memory were demonstrated: (a) older adults were more likely than were young adults to say that they saw information that was actually only suggested to them; (b) older adults were more confident in their false memories than were young adults; (c) older adults were less confident in their accurate memory for the source of information than were young adults. Together, the data suggest that older adults either lacked or failed to use helpful diagnostic source information (e.g. perceptual details or temporal information), and that their confidence in their false memories reflected an over-weighting of semantic information. Copyright © 2002 John Wiley & Sons, Ltd.
This research investigated whether generating misinformation impairs memory for actual information. After watching a videotaped robbery, some witnesses were interviewed about it, but others did not rehearse the event details. One week later, the witnesses tried to remember the robber's appearance. In Experiment 1, those who fabricated a description of the robber during the interview and those who did not rehearse remembered fewer correct details than did truthful witnesses or those who fabricated about another person. Witnesses who fabricated about the robber also reported more incorrect details than did truthful or non-interviewed witnesses. In Experiment 2, witnesses who fabricated about the robber performed as poorly on the memory test as did witnesses who answered interview questions using false information prepared for them. In both experiments deceptive witnesses sometimes reported invented details on the memory test, suggesting that they may have come to believe some fabrications.
This research was an investigation of children's performance on a task that requires memory binding. In Experiments 1 and 2, 4-year-olds, 6-year-olds, and adults viewed complex pictures and were tested on memory for isolated parts in the pictures and on the part combinations (combination condition). The results suggested improvement in memory for the combinations between the ages of 4 and 6 years but not in memory for the isolated parts. In Experiments 2 and 3, the authors also examined the developmental relationship between performance in the combination condition and free recall of a naturalistic event, finding preliminary evidence that performance on a memory task that requires binding is positively related to performance in episodic memory.
The familiarity of names produced by their prior presentation can be misinterpreted as fame. We used this false fame effect to separately study the effects of divided attention on familiarity versus conscious recollection. In a first experiment, famous and nonfamous names were presented to be read under conditions of full vs. divided attention. Divided attention greatly reduced later recognition memory performance but had no effect on gains in familiarity as measured by fame judgments. In later experiments, we placed recognition memory and familiarity in opposition by presenting only nonfamous names to be read in the first phase. Recognizing a name as earlier read on the later fame test allowed Ss to be certain that it was nonfamous. Divided attention at study or during the fame test reduced list recognition performance but had no effect on familiarity. We conclude that conscious recollection is an attention-demanding act that is separate from assessing familiarity. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
The hypothesis that misleading suggestions can impair recollection was supported in a study inspired by L. L. Jacoby and C. M. Kelley's (unpublished manuscript) "logic of opposition" and D. S. Lindsay and M. K. Johnson's (see record
1989-38908-001) hypotheses about source memory. Tendency to report suggested details was set in opposition to ability to remember their source by telling Ss not to report anything from the narrative. Conditions were manipulated so that in the high- but not the low-discriminability condition it was easy to remember the suggestions and their source. At test, Ss were told (truthfully) that any information in the narrative relevant to the questions was wrong. Suggested details were more often reported on misled than control items in the low- but not the high-discriminability condition, yet suggestions impaired accurate recall of event details in both conditions. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Suggests that detecting memory impairment with the modified test relies on long retention intervals that provide the necessary forgetting of event information for impairing effects of postevent misinformation to occur. 288 Ss were tested in 4 experiments that presented event items centrally, introduced verbal postevent items to a misled condition, and used the modified test, but differed by using either short (15 min) or long (5–7 days) retention intervals. As evidenced by poorer misled than control test performances, memory impairment only occurred with long retention intervals. Retrieval- and storage-based versions of memory-impairment hypotheses are assessed. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
How is memory for a target event impaired by learning related events? The present experiments addressed the question by showing nature pictures (targets) that were followed by related pictures (experimental items) or by unrelated pictures (control items). When instructed to choose the studied picture over a new distractor, performance was more accurate for control items than for experimental items (RI) at a 15-min retention interval (Exps 1, 4, and 5). Because the RI decreased and was negligible within 48 hrs (Exp 2), the original trace could not have been displaced or altered by the related events. Further, if the related events had created traces that competed or were confused with the target, then interference would also be expected when the related pictures preceded the target (PI). However, no PI was found either after 15 min (Exps 3, 4, and 5) or after 48 hrs (Exp 6). Alternate interpretations are offered to explain the findings. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
McCloskey and Zaragoza (1985a) have recently argued that all item-specific retroactive interference (RI) can be attributed to response bias or demand characteristics. These sources of RI were eliminated in the present studies by a modified recognition test that excluded the interpolated item. Nature pictures were shown; some were followed by related pictures (experimental), and others were followed by dissimilar pictures (control). When forced to choose between two related pictures (the original and a new picture), the original picture was chosen more often for control than for experimental items (Experiments 1 and 2). Paired-associate studies were cited that have found RI in analogous matching recognition tests. These findings contradict McCloskey and Zaragoza's conclusion and must be attributed to some other cause of item-specific RI, such as trace alteration (e.g., Loftus, 1979). Experiments 3 and 4 showed that most items must be accessible in order to detect RI in the forced-choice modified test. However, even with sensitive measures, RI has not always been found in modified recognition. Suggestions are offered to explain the discrepant results. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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.
In three experiments involving a total of 623 subjects, a series of slides was shown depicting a student in a college bookstore
stealing a variety of items. Next, subjects read a narrative describing the event that contained some misinformation and some
neutral information about several critical details. Finally, subjects took a memory test. On this test, subjects were asked
to list exemplars of 20 specified categories but were instructed not to list any items that they saw in the slide sequence.
Analogous to Lindsay's (1990) adaptation of Jacoby, Woloshyn, and Kelley's (1989) “logic-ofopposition” paradigm, the tendency
to report suggested details was thus set in opposition to the ability to remember the source of those details. Therefore,
we interpreted failure to include suggested details as exemplars as evidence that subjects believed those details had been
present in the event. Analysis of subjects' responses under opposition instructions suggests that some misled subjects come
to genuinely believe that they saw items that, in reality, were only suggested to them.
A total of 1,242 subjects, in five experiments plus a pilot study, saw a series of slides depicting a single auto-pedestrian accident. The purpose of these experiments was to investigate how information supplied after an event influences a witness's memory for that event. Subjects were exposed to either consistent, misleading, or irrelevant information after the accident event. Misleading information produced less accurate responding on both a yes-no and a two-alternative forced-choice recognition test. Further, misleading information had a larger impact if introduced just prior to a final test rather than immediately after the initial event. The effects of misleading information cannot be accounted for by a simple demand-characteristics explanation. Overall, the results suggest that information to which a witness is exposed after an event, whether that information is consistent or misleading, is integrated into the witness's memory of the event.
The four experiments reported here provide evidence that (1) misleading postevent suggestions can impair memory for details in a witnessed event and (2) subjects sometimes remember suggested details as things seen in the event itself. All four experiments used recall tests in which subjects were warned of the possibility that the postevent information included misleading suggestions and were instructed to report both what they witnessed in the event and what was mentioned in the postevent narrative. Recall of event details was poorer on misled items than on control items, and subjects sometimes misidentified the sources of their recollections. Our results suggest that these findings are not due to guessing or response biases, but rather reflect genuine memory impairment and source monitoring confusions.
Although the suggestibility of eyewitness memory is well documented, previous studies have not clearly established the extent to which misled Ss might come to believe they actually remember seeing the suggested details they report. To assess whether Ss confuse misleading suggestions for their "real memories" of a witnessed event, Ss were asked specific questions about their memory for the source of suggested items. The results of 5 experiments showed that misled Ss do sometimes come to believe they remember seeing items that were merely suggested to them, a phenomenon we refer to as the source misattribution effect. Nevertheless, the results also showed that the magnitude of this effect varies and that source misattributions are not an inevitable consequence of exposure to suggestions.
A framework for understanding source monitoring and relevant empirical evidence is described, and several related phenomena are discussed: old-new recognition, indirect tests, eyewitness testimony, misattributed familiarity, cryptomnesia, and incorporation of fiction into fact. Disruptions in source monitoring (e.g., from confabulation, amnesia, and aging) and the brain regions that are involved are also considered, and source monitoring within a general memory architecture is discussed. It is argued that source monitoring is based on qualities of experience resulting from combinations of perceptual and reflective processes, usually requires relatively differentiated phenomenal experience, and involves attributions varying in deliberateness. These judgments evaluate information according to flexible criteria and are subject to error and disruption. Furthermore, diencephalic and temporal regions may play different roles in source monitoring than do frontal regions of the brain.
The purpose of the present study was to extend research on repetition and illusory truth to the domain of eyewitness suggestibility Specifically, we assessed whether repeated exposure to suggestion, relative to a single exposure, facilitates the creation of false memory for suggested events After viewing a video of a burglary, subjects were asked questions containing misleading suggestions, some of which were repeated Their memory for the source of the suggestions was tested The results show that following repeated (relative to a single) exposure to suggestion, subjects were more likely to (a) claim with high confidence that they remembered the suggested events from the video (Experiment 1) and (b) claim that they consciously recollected witnessing the suggested events (Experiment 2) The effects of repeated exposure were highly reliable and were observed over retention intervals as long as 1 week
We examined the possibility that eyewitness suggestibility reflects failures of the processes by which people normally discriminate between memories derived from different sources. To test this hypothesis, misled and control subjects were tested either with a yes/no recognition test or with a "source monitoring" test designed to orient subjects to attend to information about the sources of their memories. The results demonstrate that suggestibility effects obtained with a recognition test can be eliminated by orienting subjects toward thinking about the sources of their memories while taking the test. Our findings indicate that although misled subjects are capable of identifying the source of their memories of misleading suggestions, they nonetheless sometimes misidentify them as memories derived from the original event. The extent to which such errors reflect genuine memory confusions (produced, for example, by lax judgment criteria) or conscious misattributions (perhaps due to demand characteristics) remains to be specified.
To what extent do children who report suggested information believe they actually remember seeing the suggested details they report? Asking whether children misremember seeing suggested items is in essence a question about children's ability to monitor the source of their memories. The current study reports the results of two experiments designed to assess potential age-related changes in subjects' ability to accurately monitor the source of suggested information either immediately or following a 1-week delay. The results of both experiments revealed that although all subjects claimed to remember seeing suggested items, the magnitude of this effect varied with age such that first-graders made more source confusions than third- and fifth-graders, who in turn made more confusions than college subjects. Our findings suggest that these age differences are not simply a function of more general age-related memory or performance deficits, but instead reflect developmental differences in the tendency to confuse suggested information for actually witnessed events.
List dierentiation and forgetting Human memory: Festschrift for
- J C Abra
- J Benton
- Underwood
Abra, J. C. (1972). List dierentiation and forgetting. In C. P. Duncan, L. Sechrest and A. W.
Melton (Eds.), Human memory: Festschrift for Benton J. Underwood (pp. 25±57). New York:
Appleton-Century-Crofts.