Associative false recognition occurs without strategic criterion shifts

Investigating a bias account of emotional false memories using a criterion warning and force choice restrictions at retrieval

Here, we add to the debate as to whether false recognition of emotional stimuli is more memory-based or more bias-based. Emotional false memory findings using the DRM paradigm have been marked by higher false alarms to negatively arousing compared to neutral critical lure items. Explanation for these findings has mainly focused on false memory-based accounts. However, here we address the question of whether a response bias for emotional stimuli can, at least in part, explain this phenomenon. In Experiment 1, we used a criterion warning, previously shown to increase more conservative responding and reduce false recognition. Experiment 2, we employed a two-alternative-forced choice test, which minimises the role of criterion setting. In both experiments, we compared false alarms to negative and neutral critical lures. We observed a significant decrease in false recognition rates for both negative and neutral critical lures under the conditions of forced choice restriction and criterion warning. However, despite these conditions, negative items, compared to their neutral counterparts, still consistently provoked a higher degree of false recognition. The discussion that follows presents an exploration of both memory-based accounts and criterion-setting explanations for the enhanced emotional false memory finding.

How do forewarnings and post-warnings affect misinformation reliance? The impact of warnings on the continued influence effect and belief regression

People often continue to rely on certain information in their reasoning, even if this information has been retracted; this is called the continued influence effect (CIE) of misinformation. One technique for reducing this effect involves explicitly warning people that there is a possibility that they might have been misled. The present study aimed to investigate these warnings' effectiveness, depending on when they were given (either before or after misinformation). In two experiments (N = 337), we found that while a forewarning did reduce reliance on misinformation, retrospectively warned participants (when the warning was placed either between the misinformation and the retraction or just before testing) relied on the misinformation to a similar degree as unwarned participants. However, the protective effect of the forewarning was not durable, as shown by the fact that reliance on the misinformation increased for over 7 days following the first testing, despite continued memory of the retraction.

Warning before misinformation exposure modulates memory encoding

Exposure to misleading information after witnessing an event can impair future memory reports about the event. This pervasive form of memory distortion, termed the misinformation effect, can be significantly reduced if individuals are warned about the reliability of post-event information before exposure to misleading information. The present fMRI study investigated whether such prewarnings improve subsequent memory accuracy by influencing encoding-related neural activity during exposure to misinformation. We employed a repeated retrieval misinformation paradigm in which participants watched a crime video (Witnessed Event), completed an initial test of memory, listened to a post-event auditory narrative that contained consistent, neutral, and misleading details (Post-Event Information), and then completed a final test of memory. At the behavioral level, participants who were given a prewarning before the Post-Event Information were less susceptible to misinformation on the final memory test compared with participants who were not given a warning (Karanian et al., Proceedings of the National Academy of Sciences of the United States of America, 117, 22771-22779, 2020). This protection from misinformation was accompanied by greater activity in frontal regions associated with source encoding (lateral PFC) and conflict detection (ACC) during misleading trials as well as a more global reduction in activity in auditory cortex and semantic processing regions (left inferior frontal gyrus) across all trials (consistent, neutral, misleading) of the Post-Event Information narrative. Importantly, the strength of these warning-related activity modulations was associated with better protection from misinformation on the final memory test (improved memory accuracy on misleading trials). Together, these results suggest that warnings modulate encoding-related neural activity during exposure to misinformation to improve memory accuracy.

Widespread frontoparietal fMRI activity is greatly affected by changes in criterion placement, not discriminability, during recognition memory and visual detection tests

Widespread frontoparietal activity is consistently observed in recognition memory tests that compare studied ("target") versus unstudied ("nontarget") responses. However, there are conflicting accounts that ascribe various aspects of frontoparietal activity to mnemonic evidence versus decisional processes. According to Signal Detection Theory, recognition judgments require individuals to decide whether the memory strength of an item exceeds an evidence threshold-the decision criterion-for reporting previously studied items. Yet, most fMRI studies fail to manipulate both memory strength and decision criteria, making it difficult to appropriately identify frontoparietal activity associated with each process. In the current experiment, we manipulated both discriminability and decision criteria across recognition memory and visual detection tests during fMRI scanning to assess how frontoparietal activity is affected by each manipulation. Our findings revealed that maintaining a conservative versus liberal decision criterion drastically affects frontoparietal activity in target versus nontarget response contrasts for both recognition memory and visual detection tests. However, manipulations of discriminability showed virtually no differences in frontoparietal activity in target versus nontarget response or item contrasts. Comparing across task domains, we observed similar modulations of frontoparietal activity across criterion conditions, though the recognition memory task revealed larger activations in both magnitude and spatial extent in these contrasts. Nonetheless, there appears to be some domain specificity in frontoparietal activity associated with the maintenance of a conservative versus liberal criterion. We propose that widespread frontoparietal activity observed in target versus nontarget contrasts is largely attributable to response bias where increased activity may reflect inhibition of a prepotent response, which differs depending on whether a person maintains a conservative versus liberal decision criterion.

Can we learn from errors? Retrieval facilitates the correction of false memories for pragmatic inferences

Errorful learning suggests that, when perfect learning has not yet been attained, errors can enhance future learning if followed by corrective feedback. Research on memory updating has shown that after retrieval, memory becomes more malleable and prone to change. Thus, retrieval of a wrong answer might provide a good context for the incorporation of feedback. Here, we tested this hypothesis using sentences including pragmatic sentence implications, commonly used for the study of false memories. Across two experiments with young adults, we hypothesized that corrective feedback would be more efficient at reducing false memories if provided immediately after retrieval, when memory is more malleable than after being exposed to the material. Participants’ memory was assessed as a function of the type of learning task (Experiment 1: retrieval vs. restudy; and Experiment 2: active vs. passive recognition); and whether participants received corrective feedback or not. In both experiments, we observed that retrieval not only improved correct recall (replicating the testing effect) but also promoted the correction of false memories. Notably, corrective feedback was more effective when given after errors that were committed during retrieval rather than after restudy (Experiment 1) or after passive recognition (Experiment 2). Our results suggest that the benefits of retrieval go beyond the testing effect since it also facilitates false memories correction. Retrieval seems to enhance memory malleability, thus improving the incorporation of feedback, compared to the mere presentation of the information. Our results support the use of learning strategies that engage in active and explicit retrieval because, even if the retrieved information is wrong—when immediate feedback is provided—memory updating is promoted and errors are more likely to be corrected.

The Trajectory of Targets and Critical Lures in the Deese/Roediger-McDermott Paradigm: A Systematic Review

The Deese/Roediger-McDermott (DRM) paradigm has been used extensively to examine false memory. During the study session, participants learn lists of semantically related items (e.g., pillow, blanket, tired, bed), referred to as targets. Critical lures are items which are also associated with the lists but are intentionally omitted from study (e.g., sleep). At test, when asked to remember targets, participants often report false memories for critical lures. Findings from experiments using the DRM show the ease with which false memories develop in the absence of suggestion or misinformation. Given this, it is important to examine factors which influence the generalizability of the findings. One important factor is the persistence of false memory, or how long false memories last. Therefore, we conducted a systemic review to answer this research question: What is the persistence of false memory for specific items in the DRM paradigm? To help answer this question our review had two research objectives: (1) to examine the trajectory of target memory and false memory for critical lures and (2) to examine whether memory for targets exceeded false memory for critical lures. We included empirical articles which tested memory for the same DRM lists with at least two testing sessions. We discuss the results with respect to single-session delays, long-term memory recall and recognition, remember and know judgments for memory, and the effect of development, valence, warning, and connectivity on the trajectory of memory. Overall, the trajectory of targets showed a relatively consistent pattern of decrease across delay. The trajectory of critical lures was inconsistent. The proportion of targets versus critical lures across delay was also inconsistent. Despite the inconsistencies, we conclude that targets and critical lures have a dissimilar trajectory across delay and that critical lures are more persistent than targets. The findings with respect to long-term recall and recognition are consistent with both Fuzzy Trace Theory and Associative-Activation Theory of the DRM effect. The generation of false memory with brief delays (3-4 s) is better explained by Associative-Activation Theory. Examining the connectivity between target items, and critical lures, and the effect that has during study and retrieval, can provide insight into the persistence of false memory for critical lures.

Item-specific encoding reduces false recognition of homograph and implicit mediated critical lures

We evaluated the effects of item-specific and relational encoding instructions on false recognition for critical lures that originated from homograph and mediated study lists. Homograph lists contained list items that were taken from two meanings of the same critical lure (e.g., autumn, trip, harvest, stumble; for fall) which disrupted thematic/gist consistency of the list. Mediated lists contained unrelated list items (e.g., slippery, spicy, vent, sleigh) that were indirectly related to a critical lure (e.g., cold), through a set of non-presented mediators (e.g., wet, hot, air, snow), and had no thematic/gist consistency. In two experiments, item-specific and relational encoding improved correct recognition relative to a read-only control task, but only item-specific encoding reduced false recognition of critical lures. Signal-detection analyses indicated that the item-specific reduction increased test-based monitoring. The item-specific reduction for homograph and mediated critical lures is consistent with the activation-monitoring framework given gist-based processes are reduced or eliminated on these list types.

Can signal detection theory explain everyday amnesia (high confident misses)?

Levi et al. (2021) critique the concept of everyday amnesia (high confident misses) by arguing that these are simply due to criterion shifts within a signal detection framework. We agree that signal detection figures can be drawn to conceptualize the results, but we argue such efforts merely provide a re-description of the phenomenon without explaining it. For that, one would need a process theory. Signal detection theory represents an elegant framework for conceiving of issues in decision making, but not for explaining mechanisms underlying them. A signal detection figure can be created for any possible recognition memory result; any pair of hit rates and false alarm rates (and hence miss rates and correct rejection rates) is amenable to such a depiction. If we were to cast the issue we raised in terms of signal detection theory, we might ask: Why do some subjects place their most liberal criterion in such a way that they miss, with high confidence, items that they recently studied? Signal detection theory provides no answer.

Individual Differences in Disqualifying Monitoring Underlie False Recognition of Associative and Conjunction Lures

The current study leveraged experimental and individual differences methodology to examine whether false memories across different list-learning tasks arise from a common cause. Participants completed multiple false memory (associative and conjunction lure), working memory (operation and reading span), and source monitoring (verbal and picture) tasks. Memory discriminability in the associative and conjunction tasks loaded onto a single (general) factor and were unaffected by warnings provided at encoding. Consistent with previous research, source-monitoring ability fully mediated the relation between working memory and false memories. Moreover, individuals with higher source monitoring-ability were better able to recall contextual information from encoding to correctly reject lures. These results suggest that there are stable individual differences in false remembering across tasks. The commonality across tasks may be due, at least in part, to the ability to effectively use disqualifying monitoring processes.

False recognitions in the DRM paradigm: the role of stress and warning

For the last decades, the factors increasing or decreasing the frequency of false memories have been of great interest. Some research also examined the effect of stress and warning on the true and false recognitions; however, so far most of the studies have yielded contradictory results or seems inadequate to understand the effect of these factors on false memory phenomenon. The purpose of this study is to examine the joint effects of stress and warning on the frequency of false and true memories elicited by the list-learning paradigm. The word lists derived from the Deese–Roediger–McDermott (DRM) paradigm were used in order to measure false and true recognition rates. Participants (N = 126) were exposed to either the Trier Social Stress Test (a stress condition) or a filler task at the beginning of the experiment (no-stress condition). Then, they were either subjected to a warning about false memories before DRM (pre-warning condition), subjected to a warning about false memories after DRM (post-warning condition), or given no warning at all (no-warning condition). Results showed that stress had a statistically significant effect on true recognition but not on false recognition. Furthermore, warning given after the DRM lists had a decreasing effect on the frequency of false memories. No significant interaction effect between stress and warning was found. Although our hypotheses were not confirmed, this study can contribute to the existing body of research by providing evidence that stress and warning have differential effects on both true and false memories derived from the DRM paradigm.

The mnemonic effects of insight on false memory in the DRM paradigm

Insight accompanied by an 'aha!' experience has a mnemonic effect. Previous studies of insight have often focused on the mnemonic effect of insight on veridical memories, while the effect of insight on false memories is not known. More understanding of the mnemonic effect of insight on false memories could have implications for the mechanism of insightful mnemonic effects. The present research examined whether insight has a mnemonic effect on false memories. Participants were asked to perform Chinese verbal compound remote associate (CRA) tasks and then complete the Deese-Roediger-McDermott (DRM) task, the critical lure of which was also the solution to the Chinese CRA problem. Compared to non-insight, insight was associated with a lower critical lures rate in Experiment 1 and with lower critical lures and unrelated words rates in Experiment 2 when the presentation of DRM list words was random. Giving a warning before DRM tasks could reduce the critical lures rate of non-insight but had little effect on insightful solutions in Experiment 3. These findings indicate that insight can reduce false memories.

Understanding Older Adults' Memory Distortion in the Light of Stereotype Threat

Numerous studies have documented the detrimental impact of age-based stereotype threat (ABST) on older adults' cognitive performance and especially on veridical memory. However, far fewer studies have investigated the impact of ABST on older adults' memory distortion. Here, we review the subset of research examining memory distortion and provide evidence for the role of stereotype threat as a powerful socio-emotional factor that impacts age-related susceptibility to memory distortion. In this review we define memory distortion as errors in memory that are associated with gist-based errors or source misattributions. Whereas, some of the reviewed experiments support the conclusion that ABST should be considered in the context of age-related differences in memory distortion, others reported little or no impact of stereotype threat. These discrepancies suggest that the role of ABST, and socio-emotional processes generally, in age-related changes in memory distortion are less clear. In this review, we argue that ABST does play an important role in age-related changes in memory distortion. We present evidence suggesting that discrepancies in the reviewed literature may be reconciled when evaluated in the context of the leading theories about stereotype threat: the Executive Resource Depletion hypothesis and the Regulatory Focus theory. We also discuss how differences in methodology and participant characteristics can account for a priori contradictory results in the literature. Finally, we propose some recommendations for researchers and practitioners when assessing memory in older adults.

Reducing False Recognition in the Deese-Roediger/McDermott Paradigm: Related Lures Reveal How Distinctive Encoding Improves Encoding and Monitoring Processes

In the Deese-Roediger/McDermott (DRM) paradigm, distinctive encoding of list items typically reduces false recognition of critical lures relative to a read-only control. This reduction can be due to enhanced item-specific processing, reduced relational processing, and/or increased test-based monitoring. However, it is unclear whether distinctive encoding reduces false recognition in a selective or global manner. To examine this question, participants studied DRM lists using a distinctive item-specific anagram generation task and then completed a recognition test which included both DRM critical lures and either strongly related lures (Experiment 1) or weakly related lures (Experiment 2). Compared to a read-control group, the generate groups showed increased correct recognition and decreased false recognition of all lure types. We then estimated the separate contributions of encoding and retrieval processes using signal-detection indices. Generation improved correct recognition by both increasing encoding of memory information for list words and by increasing memory monitoring at test. Generation reduced false recognition by reducing the encoding of memory information and by increasing memory monitoring at test. The reduction in false recognition was equivalent for critical lures and related lures, indicating that generation globally reduces the encoding of related non-presented items at study (not just critical lures), while globally increasing list-theme-based monitoring at test.

Multiple species of distinctiveness in memory? Comparing encoding versus statistical distinctiveness on recognition

The distinctiveness effect refers to the memorial benefit of processing unique or item-specific features of a memory set relative to a non-distinctive control. Traditional distinctiveness effects are accounted for based on qualitative differences in how distinctive items are encoded and subsequently retrieved. This study evaluates whether a separate species of distinctiveness - statistical distinctiveness - may provide an additional benefit to memory beyond traditional task-based processes. Statistical distinctiveness refers to the relative frequency with which a specific memory item or set is processed. The current study examined the presence of statistical distinctiveness through a series of levels-of-processing mixed groups in which related lists were studied using two of the following three tasks to promote either shallow ("E" identification), neutral (reading silently), or deep/distinctive (pleasantness ratings) processing followed by a recognition test. Participants studied lists in which these tasks were used frequently (80% of lists), equally (50% of lists), or infrequently (20% of lists). No recognition advantage was found when tasks were completed infrequently versus frequently. Instead, recognition was greatest for the deeper/more distinctive task - a pattern consistent with an encoding but not a statistical distinctiveness account.

Does Test Type Influence False Recognition in the DRM Paradigm? Comparison of the Yes/No Recognition Test and Two-Alternative Forced-Choice Test

Studies attempting to identify the mechanisms that are responsible for the level of false recognition in the DRM paradigm usually apply a manipulation during encoding. The main aim of the studies reported here was to investigate the within- and between-participant effects of a testing method on memory performance using a standard yes/no recognition test and a 2-alternative forced-choice recognition test (2FC). To allow a direct comparison of the 2 testing methods, a 2FC test containing similar items as a typical yes/no test in the DRM paradigm was elaborated on in the pilot study. Moreover, 2 methods of data calculation were used: comparing rates of hit and false alarms with critical lures and with unstudied and unrelated items between the 2 tests and comparing measures of sensitivity (d’) derived from signal detection theory. Both experiments showed a lower false alarm rate to critical lures and higher hit rate in a 2FC test as compared with a yes/no test, depicting a typical mirror effect. A within-participant design (Experiment 1) also showed that this increased accuracy of a 2FC test diminished when memory performance was expressed in terms of a sensitivity measure, which may suggest that similar processes are used during these 2 retrieval methods. A similar analysis performed for a between-participants design (Experiment 2) revealed that a 2FC test was less susceptible to associative memory distortions, but the quality of memory (“remember/know” judgments) remained similar for both tests.

When do pictures reduce false memory?

An important discovery in false-memory research is Israel and Schacter's (Psychonomic Bulletin & Review, 4, 577-581, 1997) finding that presenting pictures at study relative to words alone reduces false memory in the DRM paradigm, a result that has been replicated many times. The standard interpretation is that memory for visual processing of the pictures can be used to reject the critical distractors, which were not explicitly present at study. Beginning from the empirical observation that the pictures used by Israel and Schacter are not consistently labelled with the DRM word they are supposed to represent, we present a series of four studies designed to determine if it is the presentation of pictures or the mismatch between the pictures and the words that reduces false memory. The results across the four experiments demonstrate that picture presentation at study is neither necessary nor sufficient to reduce false memory in the DRM and the categorical associate paradigms. However, we discuss other studies in which picture processing clearly is responsible for reduction of false alarms and note that these studies use study materials and memory tests that are different from the DRM and categorical associate paradigms in that critical lures are externally provided rather than generated. We speculate that the effectiveness of memory for visual processing for reducing false memory may depend on the source of the false memory, but this remains for future research.

Memory for the usual: the influence of schemas on memory for non-schematic information in younger and older adults

Schemas are abstract mental representations that influence perceptual and memory processes. Schemas can aide memory for information that is related or congruent with a given schema (i.e., schematic information), yet it is unclear how schemas affect memory for information that does not directly relate to the schema (i.e., non-schematic information). Using a novel scene paradigm, the current series of studies investigated how schemas affect memory for schematic and non-schematic information, as well as how directed encoding influences remembering of both types of information in younger and older adults. Results showed poorer accurate recognition of non-schematic information relative to schematic information, influenced largely by a bias in identifying non-schematic items as "new". While directed encoding was able to increase remembering of non-schematic information and decrease bias across both age groups, the present set of studies highlights the pervasive influence of a schema on memory for non-schematic information.

Item-specific processing reduces false recognition in older and younger adults: Separating encoding and retrieval using signal detection and the diffusion model

Our study examined processing effects in improving memory accuracy in older and younger adults. Specifically, we evaluated the effectiveness of item-specific and relational processing instructions relative to a read-only control task on correct and false recognition in younger and older adults using a categorized-list paradigm. In both age groups, item-specific and relational processing improved correct recognition versus a read-only control task, and item-specific encoding decreased false recognition relative to both the relational and read-only groups. This pattern was found in older adults despite overall elevated rates of false recognition. We then applied signal-detection and diffusion-modeling analyses, which separately utilized recognition responses and the latencies to those responses to estimate contributions of encoding and monitoring processes on recognition decisions. Converging evidence from both analyses demonstrated that item-specific processing benefits to memory accuracy were due to improvements of both encoding (estimates of d' and drift rate) and monitoring (estimates of lambda and boundary separation) processes, and, importantly, occurred similarly in both younger and older adults. Thus, older and younger adults showed similar encoding-based and test-based benefits of item-specific processing to enhance memory accuracy.

Item-specific and relational processing both improve recall accuracy in the DRM paradigm

Using the Deese-Roediger-McDermott (DRM) paradigm, Huff and Bodner found that both item-specific and relational variants of a task improved correct recognition, but only the item-specific variants reduced false recognition, relative to a read-control condition. Here, we examined the outcome pattern when memory was tested using free recall, using the same item-specific versus relational task variants across three experiments as our previous study (processing instructions, pleasantness ratings, anagram generation). The outcome pattern in recall was similar to recognition, except relational processing at study actually reduced the DRM illusion, though not as much as item-specific processing. To reconcile this task difference, we suggest that the memory information laid down during relational encoding enhances the familiarity of the critical items at test. To the extent that familiarity is used less as a basis for responding in free recall than in recognition, relational processing ironically reduces rather than increases the DRM illusion in recall.

Mood impedes monitoring of emotional false memories: evidence for the associative theories

In the present experiment, we investigated whether warnings provided at the time of retrieval would reduce emotional false memories in the Deese-Roediger-McDermott (DRM) paradigm. The provision of retrieval warnings allowed us to test specific predictions based on the associative theories (e.g., Activation-Monitoring Theory; AMT) and Fuzzy-Trace Theory (FTT) that have been used to account for false memories in the DRM paradigm. Participants were randomly assigned to either a no-warning group or a retrieval-warning group. In each group, mood-induction procedures were used to elicit a positive, negative, or neutral mood and participants were then presented with word lists comprised of positive, negative, or neutral words. Retrieval warnings reduced false recognition, regardless of the valence of the to-be-remembered information or participants' mood. Consistent with the associative theories' predictions, within the warning condition, positive moods yielded greater false recognition for positive critical lures, and negative moods yielded greater false recognition for negative critical lures, compared to neutral moods. These findings have important practical implications for our understanding of the effect of mood on memory.

Transfer of learning in avoiding false memory: The roles of warning, immediate feedback, and incentive

Participants learned semantic associates and were tested in the Deese–Roediger–McDermott (DRM) paradigm. A multiple-trial learning procedure with warning, feedback, and monetary incentive was employed to reduce false memory. Results showed that there was a progressive reduction of false memory over the trials as well as a generalization of learning to new lists of words in avoiding the critical nonpresented words attributable to explicit warning, feedback, and incentive, respectively. Both the feedback and the monetary incentive had an effect beyond what an explicit warning could obtain. In addition, participants were found to achieve false-memory reduction by enhancing the activation of the critical words and the monitoring process, rather than by strengthening the verbatim processing of the list words. It was concluded that false memory may not be as impervious to correction as was believed insofar as an effective training method is applied.

The role of decision criterion in the Deese-Roediger-McDermott (DRM) false recognition memory: False memory falls and rises as a function of restriction on criterion setting

How much of the Deese-Roediger-McDermott (DRM) false memory is attributable to decision criterion is so far a controversial issue. Previous studies typically used explicit warnings against accepting the critical lure to investigate this issue. The assumption is that if the false memory results from using a liberally biased criterion, it should be greatly reduced or eliminated by an explicit warning against accepting the critical lure. Results showed that warning was generally ineffective. We asked the question of whether subjects can substantially reduce false recognition without being warned when the test forces them to make a distinction between true and false memories. Using a two-alternative forced choice in which criterion plays a relatively smaller role, we showed that subjects could indeed greatly reduce the rate of false recognition. However, when the forced-choice restriction was removed from the two-item choice test, the rate of false recognition rebounded to that of the hit for studied list words, indicating the role of criterion in false recognition.

Associative false consumer memory: effects of need for cognition and encoding task

Two experiments investigated the effects of product-attribute associations on false consumer memory. In both experiments, subjects were presented with sets of related product attributes under incidental encoding conditions. Later, recognition memory was tested with studied attributes, non-studied but associated attributes (critical lures) and non-studied unrelated attributes. In Experiment 1, the effect of Need for Cognition (NFC) was assessed. It was found that individuals high in NFC recognised more presented attributes and falsely recognised more associative critical lures. The increase in both true and associative false memory was accompanied by a greater number of responses that index the retrieval of detailed episodic-like information. Experiment 2, replicated the main findings through an experimental manipulation of the encoding task that required subjects to consider purchase likelihood. Explanations for these findings are considered from the perspective of activation processes and knowledge structures in the form of gist-based representations.

Stereotypes, Warnings, and Identity-Related Variables Influence Older Adults' Susceptibility to Associative False Memory Errors

Background and Objectives

Activating ageist stereotypes can impair older adults' ability to remember information. This effect has been shown to be strongest for older adults who possess certain characteristics (e.g., young-old, highly educated). The present study extended this line of research to investigate the relationship between stereotyping and false memory susceptibility in older adults.

Research Design and Methods

We first presented older adults with lists of associated words in an incidental learning paradigm. Afterward, we manipulated whether participants were presented with stereotypes about aging and whether they were given warnings about the associative nature of the lists. Participants then completed a yes/no recognition test and answered demographic questions.

Results

Older adults in the stereotyped group were more likely to falsely recognize non-presented theme words than older adults in the control group. Further, those who were highly educated and/or retired were most likely to experience this false memory susceptibility.

Discussion and Implications

Similar to the research on veridical memory, these findings suggest that the effects of ageist stereotyping on older adults' false memory susceptibility may be best understood in terms of the individual differences that older adults possess. Identifying the types of people who are at risk of experiencing stereotype threat is an important step toward helping older adults avoid memory impairment in the presence of common stereotypes.

Reduced effects of pictorial distinctiveness on false memory following dynamic visual noise

High levels of false recognition for non-presented items typically occur following exposure to lists of associated words. These false recognition effects can be reduced by making the studied items more distinctive by the presentation of pictures during encoding. One explanation of this is that during recognition, participants expect or attempt to retrieve distinctive pictorial information in order to evaluate the study status of the test item. If this involves the retrieval and use of visual imagery, then interfering with imagery processing should reduce the effectiveness of pictorial information in false memory reduction. In the current experiment, visual-imagery processing was disrupted at retrieval by the use of dynamic visual noise (DVN). It was found that effects of DVN dissociated true from false memory. Memory for studied words was not influenced by the presence of an interfering noise field. However, false memory was increased and the effects of picture-induced distinctiveness was eliminated. DVN also increased false recollection and remember responses to unstudied items.

Getting at the source of distinctive encoding effects in the DRM paradigm: evidence from signal-detection measures and source judgments

Studying Deese-Roediger-McDermott (DRM) lists using a distinctive encoding task can reduce the DRM false memory illusion. Reductions for both distinctively encoded lists and non-distinctively encoded lists in a within-group design have been ascribed to use of a distinctiveness heuristic by which participants monitor their memories at test for distinctive-task details. Alternatively, participants might simply set a more conservative response criterion, which would be exceeded by distinctive list items more often than all other test items, including the critical non-studied items. To evaluate these alternatives, we compared a within-group who studied 5 lists by reading, 5 by anagram generation, and 5 by imagery, relative to a control group who studied all 15 lists by reading. Generation and imagery improved recognition accuracy by impairing relational encoding, but the within group did not show greater memory monitoring at test relative to the read control group. Critically, the within group's pattern of list-based source judgments provided new evidence that participants successfully monitored for distinctive-task details at test. Thus, source judgments revealed evidence of qualitative, recollection-based monitoring in the within group, to which our quantitative signal-detection measure of monitoring was blind.

Effects of distinctive encoding on correct and false memory: a meta-analytic review of costs and benefits and their origins in the DRM paradigm

We review and meta-analyze how distinctive encoding alters encoding and retrieval processes and, thus, affects correct and false recognition in the Deese–Roediger–McDermott (DRM) paradigm. Reductions in false recognition following distinctive encoding (e.g., generation), relative to a nondistinctive read-only control condition, reflected both impoverished relational encoding and use of a retrieval-based distinctiveness heuristic. Additional analyses evaluated the costs and benefits of distinctive encoding in within-subjects designs relative to between-group designs. Correct recognition was design independent, but in a within design, distinctive encoding was less effective at reducing false recognition for distinctively encoded lists but more effective for nondistinctively encoded lists. Thus, distinctive encoding is not entirely “cost free” in a within design. In addition to delineating the conditions that modulate the effects of distinctive encoding on recognition accuracy, we discuss the utility of using signal detection indices of memory information and memory monitoring at test to separate encoding and retrieval processes.

Reducing the Misinformation Effect Through Initial Testing: Take Two Tests and Recall Me in the Morning?

Initial retrieval of an event can reduce people's susceptibility to misinformation. We explored whether protective effects of initial testing could be obtained on final free recall and source-monitoring tests. After studying six household scenes (e.g., a bathroom), participants attempted to recall items from the scenes zero, one, or two times. Immediately or after a 48-hour delay, non-presented items (e.g., soap and toothbrush) were exposed zero, one, or four times through a social contagion manipulation in which participants reviewed sets of recall tests ostensibly provided by other participants. A protective effect of testing emerged on a final free recall test following the delay and on a final source-memory test regardless of delay. Taking two initial tests did not increase these protective effects. Determining whether initial testing will have protective (versus harmful) effects on memory has important practical implications for interviewing eyewitnesses.

Erroneous and veridical recall are not two sides of the same coin: Evidence from semantic distraction in free recall

Two experiments examined the extent to which erroneous recall blocks veridical recall using, as a vehicle for study, the disruptive impact of distractors that are semantically similar to a list of words presented for free recall. Instructing participants to avoid erroneous recall of to-be-ignored spoken distractors attenuated their recall but this did not influence the disruptive effect of those distractors on veridical recall (Experiment 1). Using an externalized output-editing procedure-whereby participants recalled all items that came to mind and identified those that were erroneous-the usual between-sequences semantic similarity effect on erroneous and veridical recall was replicated but the relationship between the rate of erroneous and veridical recall was weak (Experiment 2). The results suggest that forgetting is not due to veridical recall being blocked by similar events.

Normative study of theme identifiability: Instructions with and without explanation of the false memory effect

False-memory illusions have been widely studied using the Deese/Roediger-McDermott paradigm (DRM). In this paradigm, words semantically related to a single nonpresented critical word are studied. In a later memory test, critical words are often falsely recalled and recognized. The present normative study was conducted to measure the theme identifiability of 60 associative word lists in Spanish that include six words (e.g., stove, coat, blanket, scarf, chill, and bonnet) that are simultaneously associated with three critical words (e.g., HEAT, COLD, and WINTER; Beato & Díez, Psicothema, 26, 457-463, 2011). Different levels of backward associative strength were used in the construction of the DRM lists. In addition, we used two types of instructions to obtain theme identifiability. In the without-explanation condition, traditional instructions were used, requesting participants to write the theme list. In the with-explanation condition, the false-memory effect and how the lists were built were explained, and an example of a DRM list and critical words was shown. Participants then had to discover the critical words. The results showed that all lists produced theme identifiability. Moreover, some lists had a higher theme identifiability rate (e.g., 61 % for the critical words LOVE, BOYFRIEND, COUPLE) than others (e.g., 24 % for CITY, PLACE, VILLAGE). After comparing the theme identifiabilities in the different conditions, the results indicated higher theme identifiability when the false-memory effect was explained than without such an explanation. Overall, these new normative data provide a useful tool for those experiments that, for example, aim to analyze the wide differences observed in false memory with DRM lists and the role of theme identifiability.

The effect of cognitive load on hemispheric asymmetries in true and false memory

Studies examining hemispheric asymmetries in false memory have shown that the right hemisphere (RH) is more susceptible to false memories compared to the left hemisphere (LH). Theories suggest that hemispheric asymmetries in true and false memory may be due to differences in representational coding and the use of top-down mechanisms in each hemisphere. In the current study, the Deese-Roediger-McDermott false memory paradigm was used in conjunction with divided visual field presentation to examine the role of top-down mechanisms in hemispheric asymmetries of true and false memory. In Experiment 1, participants studied lists of related words while completing secondary cognitive load tasks. In Experiment 2, the secondary tasks were administered during memory retrieval instead of memory encoding. Results revealed that cognitive loads imposed during the study phase influenced veridical memory in the LH more than the RH, but cognitive loads imposed during retrieval did not influence veridical memory in either hemisphere. Surprisingly, false memory rates were not influenced by cognitive loads and were higher in the LH. These data provide evidence that, at least for veridical memory, top-down control mechanisms are used more readily for the encoding of information into memory in the LH compared to the RH.

Reported serial positions of true and illusory memories in the Deese/Roediger/McDermott paradigm

One of the easiest ways to induce illusory memories in the laboratory is to use the Deese-Roediger-McDermott (DRM) word-list paradigm. Researchers have used this paradigm not only to study people's memories of stimuli that were not actually presented, but also to study the phenomenological qualities of these illusions. In four experiments, the current investigation explored a phenomenological quality of illusory memories that has received almost no attention, specifically, temporality. A serial position task was incorporated into the DRM paradigm to examine temporal attributes of participants' true and false memories. Effects of list strength, presentation order, and types of warnings were examined. Results showed consistent serial position responses for true and false memories. However, only responses for illusory memories were affected by manipulations at study. The current findings thus lend support to encoding-based explanations of false recollections.

Stereotype threat reduces false recognition when older adults are forewarned

Exposing older adults to ageing stereotypes can reduce their memory for studied information--a phenomenon attributed to stereotype threat--but little is known about stereotype effects on false memory. Here, we assessed ageing stereotype effects on the Deese-Roediger-McDermott false memory illusion. Older adults studied lists of semantically associated words, and then read a passage about age-related memory decline (threat condition) or an age-neutral passage (control condition). They then took a surprise memory test with a warning to avoid false recognition of non-studied associates. Relative to the control condition, activating stereotype threat reduced the recognition of both studied and non-studied words, implicating a conservative criterion shift for associated test words. These results indicate that stereotype threat can reduce false memory, and they help to clarify mixed results from prior ageing research. Consistent with the regulatory focus hypothesis, threat motivates older adults to respond more conservatively when error-prevention is emphasised at retrieval.

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.

False recognition of instruction-set lures

False remembering has been examined using a variety of procedures, including the Deese-Roediger-McDermott procedure, the false fame procedure and the two-list recognition procedure. We present six experiments in a different empirical framework examining false recognition of words included in the experimental instructions (instruction-set lures). The data show that participants' false alarm rate to instruction-set lures was twice their false alarm rate to standard lures. That result was statistically robust even when (1) the relative strength of targets to instruction-set lures was increased, (2) participants were warned about the instruction-set lures, (3) the instruction-set lures were camouflaged in the study instructions and (4) the instruction-set lures were presented verbally at study but visually at test. False recognition of instruction-set lures was only mitigated when participants were distracted between encountering the instruction-set lures and studying the training list. The results confirm the ease with which recognition succumbs to familiarity and demonstrate the robustness of false recognition.

Dissociating electrophysiological correlates of subjective, objective, and correct memory in investigating the emotion-induced recognition bias

Performance on tasks requiring discrimination of at least two stimuli can be viewed either from an objective perspective (referring to actual stimulus differences), or from a subjective perspective (corresponding to participant's responses). Using event-related potentials recorded during an old/new recognition memory test involving emotionally laden and neutral words studied either blockwise or randomly intermixed, we show here how the objective perspective (old versus new items) yields late effects of blockwise emotional item presentation at parietal sites that the subjective perspective fails to find, whereas the subjective perspective ("old" versus "new" responses) is more sensitive to early effects of emotion at anterior sites than the objective perspective. Our results demonstrate the potential advantage of dissociating the subjective and the objective perspective onto task performance (in addition to analyzing trials with correct responses), especially for investigations of illusions and information processing biases, in behavioral and cognitive neuroscience studies.

Age differences in the neural correlates of novelty processing: The effects of item-relatedness

Past research finds that age-related increases in false recognitions are a key contributor to age-related memory decline, suggesting that older adults have difficulty in correctly distinguishing between new and old information, particularly when new items at retrieval are semantically or perceptually related to items from encoding. However, little work has examined the neural mechanisms older adults engage to avoid false recognitions and successfully identify information as novel. In the present study, young and older adults were scanned during a retrieval task in which new items were exemplars from studied categories (related lures) or unstudied categories (unrelated lures) in order to detect age-related differences in the neural correlates of related and unrelated novelty processing. Results showed that, unlike young adults, older adults did not differentially recruit regions such as the anterior cingulate and bilateral middle/inferior temporal gyrus to capitalize on the salient categorical differences in unrelated items. Likewise, older adults did not differentially recruit regions of early visual cortex or anterior hippocampus, suggesting that older adults have difficulty using item-specific details to make successful related novelty decisions. Instead, older adults recruited bilateral ventrolateral prefrontal cortex differentially for successful novelty processing and particularly for related novelty processing. Overall, results suggest that age deficits in novelty processing may arise because older adults process related and unrelated lures similarly and do not capitalize on categorical or item-specific properties of novel items. Similar to aging patterns in memory retrieval, results also showed that older adults have the strongest novelty success activity in lateral PFC regions associated with control and monitoring processes. This article is part of a Special Issue entitled SI: Memory & Aging.

Investigating the variability of memory distortion for an analogue trauma

In this paper, we examine whether source monitoring (SM) errors might be one mechanism that accounts for traumatic memory distortion. Participants watched a traumatic film with some critical (crux) and non-critical (non-crux) scenes removed. Twenty-four hours later, they completed a memory test. To increase the likelihood participants would notice the film's gaps, we inserted visual static for the length of each missing scene. We then added manipulations designed to affect people's SM behaviour. To encourage systematic SM, before watching the film, we warned half the participants that we had removed some scenes. To encourage heuristic SM some participants also saw labels describing the missing scenes. Adding static highlighting, the missing scenes did not affect false recognition of those missing scenes. However, a warning decreased, while labels increased, participants' false recognition rates. We conclude that manipulations designed to affect SM behaviour also affect the degree of memory distortion in our paradigm.

Competitive Trace Theory: A Role for the Hippocampus in Contextual Interference during Retrieval

Much controversy exists regarding the role of the hippocampus in retrieval. The two dominant and competing accounts have been the Standard Model of Systems Consolidation (SMSC) and Multiple Trace Theory (MTT), which specifically make opposing predictions as to the necessity of the hippocampus for retrieval of remote memories. Under SMSC, memories eventually become independent of the hippocampus as they become more reliant on cortical connectivity, and thus the hippocampus is not required for retrieval of remote memories, only recent ones. MTT on the other hand claims that the hippocampus is always required no matter the age of the memory. We argue that this dissociation may be too simplistic, and a continuum model may be better suited to address the role of the hippocampus in retrieval of remote memories. Such a model is presented here with the main function of the hippocampus during retrieval being "recontextualization," or the reconstruction of memory using overlapping traces. As memories get older, they are decontextualized due to competition among partially overlapping traces and become more semantic and reliant on neocortical storage. In this framework dubbed the Competitive Trace Theory (CTT), consolidation events that lead to the strengthening of memories enhance conceptual knowledge (semantic memory) at the expense of contextual details (episodic memory). As a result, remote memories are more likely to have a stronger semantic representation. At the same time, remote memories are also more likely to include illusory details. The CTT is a novel candidate model that may provide some resolution to the memory consolidation debate.