The impersistence of false memory persistence

When subjects study lists of thematically related words they sometimes falsely recognise non-presented words related to the theme. The gist extraction account of these findings provided by fuzzy trace theory suggests that false recognition should decline substantially more slowly than true recognition across a delay. In two experiments we demonstrated that corrected recognition of targets and critical lures can decrease by equivalent amounts across a 48-hour delay. However the results for uncorrected recognition were mixed. In Experiment 1 we found evidence that uncorrected recognition of targets declined more rapidly than uncorrected recognition of critical lures. In Experiment 2, we found evidence that uncorrected recognition of targets and critical lures declined at equivalent rates. Results are discussed in terms of their implications for fuzzy trace and source monitoring accounts of false memories.     

A synchronization account of false recognition

We describe a computational model to explain a variety of results in both standard and false recognition. A key attribute of the model is that it uses plausible semantic representations for words, built through exposure to a linguistic corpus. A study list is encoded in the model as a gist trace, similar to the proposal of fuzzy trace theory (Brainerd & Reyna, 2002), but based on realistically structured semantic representations of the component words. The model uses a decision process based on the principles of neural synchronization and information accumulation. The decision process operates by synchronizing a probe with the gist trace of a study context, allowing information to be accumulated about whether the word did or did not occur on the study list, and the efficiency of synchronization determines recognition. We demonstrate that the model is capable of accounting for standard recognition results that are challenging for classic global memory models, and can also explain a wide variety of false recognition effects and make item-specific predictions for critical lures. The model demonstrates that both standard and false recognition results may be explained within a single formal framework by integrating realistic representation assumptions with a simple processing mechanism.     

A synchronization account of false recognition

We describe a computational model to explain a variety of results in both standard and false recognition. A key attribute of the model is that it uses plausible semantic representations for words, built through exposure to a linguistic corpus. A study list is encoded in the model as a gist trace, similar to the proposal of fuzzy trace theory (Brainerd & Reyna, 2002), but based on realistically structured semantic representations of the component words. The model uses a decision process based on the principles of neural synchronization and information accumulation. The decision process operates by synchronizing a probe with the gist trace of a study context, allowing information to be accumulated about whether the word did or did not occur on the study list, and the efficiency of synchronization determines recognition. We demonstrate that the model is capable of accounting for standard recognition results that are challenging for classic global memory models, and can also explain a wide variety of false recognition effects and make item-specific predictions for critical lures. The model demonstrates that both standard and false recognition results may be explained within a single formal framework by integrating realistic representation assumptions with a simple processing mechanism.     

The case against memory consolidation in REM sleep

We present evidence disputing the hypothesis that memories are processed or consolidated in REM sleep. A review of REM deprivation (REMD) studies in animals shows these reports to be about equally divided in showing that REMD does, or does not, disrupt learning/memory. The studies supporting a relationship between REM sleep and memory have been strongly criticized for the confounding effects of very stressful REM deprivation techniques. The three major classes of antidepressant drugs, monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs), and selective serotonin reuptake inhibitors (SSRIs), profoundly suppress REM sleep. The MAOIs virtually abolish REM sleep, and the TCAs and SSRIs have been shown to produce immediate (40-85%) and sustained (30-50%) reductions in REM sleep. Despite marked suppression of REM sleep, these classes of antidepressants on the whole do not disrupt learning/memory. There have been a few reports of patients who have survived bilateral lesions of the pons with few lingering complications. Although these lesions essentially abolished REM sleep, the patients reportedly led normal lives. Recent functional imaging studies in humans have revealed patterns of brain activity in REM sleep that are consistent with dream processes but not with memory consolidation. We propose that the primary function of REM sleep is to provide periodic endogenous stimulation to the brain which serves to maintain requisite levels of central nervous system (CNS) activity throughout sleep. REM is the mechanism used by the brain to promote recovery from sleep. We believe that the cumulative evidence indicates that REM sleep serves no role in the processing or consolidation of memory.     

An association account of false belief understanding

The elicited-response false belief task has traditionally been considered as reliably indicating that children acquire an understanding of false belief around 4 years of age. However, recent investigations using spontaneous-response tasks suggest that false belief understanding emerges much earlier. This leads to a developmental paradox: if young infants already understand false belief, then why do they fail the elicited-response false belief task? We postulate two systems to account for the development of false belief understanding: an association module, which provides infants with the capacity to register congruent associations between agents and objects, and an operating system, which allows them to transform these associations into incongruent associations through a process of inhibition, selection and representation. The interaction between the association module and the operating system enables infants to register increasingly complex associations on the basis of another agent’s movements, visual perspective and propositional attitudes. This allows us account for the full range of findings on false belief understanding.     

The effect of false memory on temporal perception

This study examined the effect of false memory on temporal perception. The Deese-Roediger-McDermott (DRM) paradigm, which elicits false recognition of a nonpresented word, was used to determine whether the perceived duration of falsely remembered words was longer than that for control words. The study results revealed that the perceived duration for falsely recognized words was longer than that for correctly rejected words. This is the first study to show the effect of false memory on temporal perception and suggests that temporal perception can be affected by conceptual fluency without any perceptual repetition.     

The robustness of false memory for emotional pictures

Emotional material is commonly reported to be more accurately recognised; however, there is substantial evidence of increased false alarm rates (FAR) for emotional material and several reports of stronger influences on response bias than accuracy. This pattern is more frequently reported for words than pictures. Research on the mechanisms underlying bias differences has mostly focused on word lists under short retention intervals. This article presents four series of experiments examining recognition memory for emotional pictures while varying arousal and the control over the content of the pictures at two retention intervals, and one study measuring the relatedness of the series picture sets. Under the shorter retention interval, emotion increased false alarms and reduced accuracy. Under the longer retention interval emotion increased hit rates and FAR, resulting in reduced accuracy and/or bias. At both retention intervals, the pattern of valence effects differed based on the arousal associated with the picture sets. Emotional pictures were found to be more related than neutral pictures in each set; however, the influence of relatedness alone does not provide an adequate explanation for all emotional differences. The results demonstrate substantial emotional differences in picture recognition that vary based on valence, arousal and retention interval.     

数字空间联结的工作记忆机制

大量研究证实数字空间联结是一种稳定存在的表征形式。而关于数字空间联结的机制目前仍存在较大争论,本文在系统整理了大量有关长时记忆"心理数字线"难以解释的研究后,分析总结了工作记忆在数字空间联结中的重要作用。基于多个研究任务分析了工作记忆不同成分,即中央执行、语音环路和视空模板等,在数字空间联结中的重要作用,并系统介绍了对数字空间联结的工作记忆序列位置的解释。总之,数字空间联结的工作记忆机制仍有较多需要解决的问题,具有进一步探索的广泛空间。     

A photo,a suggestion,a false memory

We examined the effect of photographs on children's memories for events that did and did not happen. Over three interviews, 10‐year olds saw three true photos and one false photo. Half the children saw a doctored photo of themselves and other family members in a hot air balloon, while the remaining half saw only the hot air balloon. At each interview, children reported what they could remember about each event, rated their confidence that the events really happened and rated how much they could remember. Children who saw the photo showing themselves in the balloon developed more false memories than those who saw only the balloon, but when children in either condition developed false memories, they were equally confident that the event was real. These data highlight a potential problem with the use of photographs as tools in therapy. Copyright © 2007 John Wiley & Sons, Ltd.     

The testing effect in recognition memory: a dual process account

The testing effect, or the finding that taking an initial test improves subsequent memory performance, is a robust and reliable phenomenon--as long as the final test involves recall. Few studies have examined the effects of taking an initial recall test on final recognition performance, and results from these studies are equivocal. In 3 experiments, we attempt to demonstrate that initial testing can change the ways in which later recognition decisions are executed even when no difference can be detected in the recognition hit rates. Specifically, initial testing was shown to enhance later recollection but leave familiarity unchanged. This conclusion emerged from three dependent measures: source memory, exclusion performance, and remember/know judgments.     

The effect of Twitter exposure on false memory formation

Social media sites such as Facebook and Twitter have increased drastically in popularity. However, information on these sites is not verified and may contain inaccuracies. It is well-established that false information encountered after an event can lead to memory distortion. Therefore, social media may be particularly harmful for autobiographical memory. Here, we tested the effect of Twitter on false memory. We presented participants with a series of images that depicted a story and then presented false information about the images in a scrolling feed that bore either a low or high resemblance to a Twitter feed. Confidence for correct information was similar across the groups, but confidence for suggested information was significantly lower when false information was presented in a Twitter format. We propose that individuals take into account the medium of the message when integrating information into memory.     

Presentation modality affects false memory

Roediger and McDermott (1995) rejuvenated interest in Deese’s (1959) paradigm for producing reliable intrusions and false alarms. Using this paradigm in three experiments, we demonstrated that visual study presentation dramatically reduces the rate of false memories. Only auditory study presentation resulted in equal production of studied and critical items. Correct recall and recognition were unaffected. The suggestion that visual presentation provides a means for discriminating between false and true memories was supported by Experiment 3: Pleasantness rating of study items significantly reduced the creation of false memories regardless of modality.     

Attentional cueing induces false memory

The fluency of stimulus processing significantly contributes to recognition memory judgments. We investigated the effect of processing fluency induced by attentional cueing on recognition judgments. Participants performed a Remember/Know recognition test, while their spatial attention was manipulated in the test session. Stimulus location was either predicted (congruent condition) or unpredicted (incongruent condition) using an arrow cue. The results revealed that familiarity-based false recognition increased in the incongruent condition wherein the participants may have attributed part of the perceived disfluency to the attentional cue, and they may have overestimated the fluency for the stimulus, leading to increased false recognition. However, in the congruent condition, the participants may have attributed some parts of the perceived fluency to the attentional cue and underestimated the fluency for the stimulus, leading to decreased false recognition. In sum, stimulus-irrelevant attentional cueing induces unintentional processing about the source of fluency and biases recognition memory.     

A few seemingly harmless routes to a false memory

Since the invention of photography we have learned to rely on photos to help us remember significant moments in our lives. We have come to believe that photographs are accurate and valuable records of events that—years down the track—we may not be able to remember. In this paper, we review recent research demonstrating that photographs can also help us to “remember” events that never really happened. We trace the development of the leading false autobiographical memory paradigm, and we then describe research on the power of both fake narrative stories and fake photographs to cultivate false memories.     

The role of rehearsal and generation in false memory creation

The current research investigated one possible mechanism underlying false memories in the Deese-Roediger-McDermott (DRM) paradigm. In the DRM paradigm, participants who study lists of related words (e.g., "table, sitting, bench ...") frequently report detailed memories for the centrally related but non-presented critical lure (e.g., "chair"). One possibility is that participants covertly call to mind the critical non-presented lure during the study phase, and later misattribute memory for this internally generated event to its external presentation. To investigate this, the DRM paradigm was modified to allow collection of on-line thoughts during the study phase. False recognition increased following generation during study. False recognition also increased following study of longer lists; this effect was partially explained by the fact that longer lists were more likely to elicit generations of the critical lure during study. Generation of the lure during study contributes to later false recognition, although it does not explain the entire effect.     

The effect of divided attention on false memory depends on how memory is tested

In three experiments, we investigated the effects of divided attention on false memory, using the Deese/Roediger-McDermott (DRM) paradigm. In Experiments 1 and 2, participants studied six DRM lists with full attention and six in one of two divided-attention conditions (random number generation or digit monitoring). Both divided-attention conditions increased false recall of related words (Experiment 1) but reduced false recognition (Experiment 2). These results were confirmed in Experiment 3, in which the type of secondary task was manipulated within groups. We argue that the increase in false recall with divided attention reflects a change in participants' response criterion, whereas the decrease in false recognition occurs because the secondary tasks prevent participants from generating associates of the words presented at study.     

The role of associative strength in children's false memory illusions

The effects of associative strength on rates of 7- and 11-year-old children's true and false memories were examined when category and Deese-Roediger-McDermott (DRM) lists were used to cue the same critical lure. Backward associative strength (BAS) was varied such that the category and DRM lists had the same strength (DRM=category), DRM lists had more BAS (DRM>category), or category lists had more BAS (DRM<category). If BAS drives children's false memories then BAS, not the type of relation across items in a list, should determine false memory production. The results confirmed this prediction using both recall and recognition measures: (1) both true and false memories increased with age, (2) true memory was better for category than DRM lists but there were no differences for false memory, and (3) at all ages, false memories varied predictably with changes in BAS but were unaffected by list-type manipulations. These findings are discussed in the context of models of false memory development.     

The role of rehearsal and generation in false memory creation

The current research investigated one possible mechanism underlying false memories in the Deese-Roediger-McDermott (DRM) paradigm. In the DRM paradigm, participants who study lists of related words (e.g., “table, sitting, bench …”) frequently report detailed memories for the centrally related but non-presented critical lure (e.g., “chair”). One possibility is that participants covertly call to mind the critical non-presented lure during the study phase, and later misattribute memory for this internally generated event to its external presentation. To investigate this, the DRM paradigm was modified to allow collection of on-line thoughts during the study phase. False recognition increased following generation during study. False recognition also increased following study of longer lists; this effect was partially explained by the fact that longer lists were more likely to elicit generations of the critical lure during study. Generation of the lure during study contributes to later false recognition, although it does not explain the entire effect.     

Driving without memory: The strength of schema-consistent false memories

Drivers’ memory for their recent trips has been shown to be surprisingly poor, with relatively low accuracy of both recall and recollection and substantial levels of false memories. Driving research has suggested that arousal, such as from risk, leads to more accurate memories. Memory research suggests that the typicality of objects and events makes them harder to remember accurately, compared to schema-inconsistent or atypical objects, and leads to greater likelihood of false memories. In contrast, it has been suggested that memory for actions is different to memory for objects, and that typical actions are remembered more accurately than atypical actions. The present research examined the role of typicality or schema consistency in the accuracy of memory for driving. Participants drove a 15 km route in their own cars and then answered questions about their drive. The results showed that atypical objects and actions were recalled with greater accuracy than typical objects and actions. The results also showed that false memories were most common for typical objects, but not for typical actions. We interpret these results in terms of both memory theory and implications for understanding skilled behaviour such as driving.