Interaction of sleep and emotional content on the production of false memories.

PubMed

McKeon, Shannon; Pace-Schott, Edward F; Spencer, Rebecca M C

2012-01-01

Sleep benefits veridical memories, resulting in superior recall relative to off-line intervals spent awake. Sleep also increases false memory recall in the Deese-Roediger-McDermott (DRM) paradigm. Given the suggestion that emotional veridical memories are prioritized for consolidation over sleep, here we examined whether emotion modulates sleep's effect on false memory formation. Participants listened to semantically related word lists lacking a critical lure representing each list's "gist." Free recall was tested after 12 hours containing sleep or wake. The Sleep group recalled more studied words than the Wake group but only for emotionally neutral lists. False memories of both negative and neutral critical lures were greater following sleep relative to wake. Morning and Evening control groups (20-minute delay) did not differ ruling out circadian accounts for these differences. These results support the adaptive function of sleep in both promoting the consolidation of veridical declarative memories and in extracting unifying aspects from memory details.

Interaction of Sleep and Emotional Content on the Production of False Memories

PubMed Central

McKeon, Shannon; Pace-Schott, Edward F.; Spencer, Rebecca M. C.

2012-01-01

Sleep benefits veridical memories, resulting in superior recall relative to off-line intervals spent awake. Sleep also increases false memory recall in the Deese-Roediger-McDermott (DRM) paradigm. Given the suggestion that emotional veridical memories are prioritized for consolidation over sleep, here we examined whether emotion modulates sleep’s effect on false memory formation. Participants listened to semantically related word lists lacking a critical lure representing each list’s “gist.” Free recall was tested after 12 hours containing sleep or wake. The Sleep group recalled more studied words than the Wake group but only for emotionally neutral lists. False memories of both negative and neutral critical lures were greater following sleep relative to wake. Morning and Evening control groups (20-minute delay) did not differ ruling out circadian accounts for these differences. These results support the adaptive function of sleep in both promoting the consolidation of veridical declarative memories and in extracting unifying aspects from memory details. PMID:23145159

Shaping memory accuracy by left prefrontal transcranial direct current stimulation.

PubMed

Zwissler, Bastian; Sperber, Christoph; Aigeldinger, Sina; Schindler, Sebastian; Kissler, Johanna; Plewnia, Christian

2014-03-12

Human memory is dynamic and flexible but is also susceptible to distortions arising from adaptive as well as pathological processes. Both accurate and false memory formation require executive control that is critically mediated by the left prefrontal cortex (PFC). Transcranial direct current stimulation (tDCS) enables noninvasive modulation of cortical activity and associated behavior. The present study reports that tDCS applied to the left dorsolateral PFC (dlPFC) shaped accuracy of episodic memory via polaritiy-specific modulation of false recognition. When applied during encoding of pictures, anodal tDCS increased whereas cathodal stimulation reduced the number of false alarms to lure pictures in subsequent recognition memory testing. These data suggest that the enhancement of excitability in the dlPFC by anodal tDCS can be associated with blurred detail memory. In contrast, activity-reducing cathodal tDCS apparently acted as a noise filter inhibiting the development of imprecise memory traces and reducing the false memory rate. Consistently, the largest effect was found in the most active condition (i.e., for stimuli cued to be remembered). This first evidence for a polarity-specific, activity-dependent effect of tDCS on false memory opens new vistas for the understanding and potential treatment of disturbed memory control.

Sleep deprivation increases formation of false memory.

PubMed

Lo, June C; Chong, Pearlynne L H; Ganesan, Shankari; Leong, Ruth L F; Chee, Michael W L

2016-12-01

Retrieving false information can have serious consequences. Sleep is important for memory, but voluntary sleep curtailment is becoming more rampant. Here, the misinformation paradigm was used to investigate false memory formation after 1 night of total sleep deprivation in healthy young adults (N = 58, mean age ± SD = 22.10 ± 1.60 years; 29 males), and 7 nights of partial sleep deprivation (5 h sleep opportunity) in these young adults and healthy adolescents (N = 54, mean age ± SD = 16.67 ± 1.03 years; 25 males). In both age groups, sleep-deprived individuals were more likely than well-rested persons to incorporate misleading post-event information into their responses during memory retrieval (P < 0.050). These findings reiterate the importance of adequate sleep in optimal cognitive functioning, reveal the vulnerability of adolescents' memory during sleep curtailment, and suggest the need to assess eyewitnesses' sleep history after encountering misleading information. © 2016 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

Novel shifts in memory research and their impact on the legal process: introduction to the special issue on memory formation and suggestibility in the legal process.

PubMed

Otgaar, Henry; Sauerland, Melanie; Petrila, John P

2013-01-01

The functioning and frailties of memory are frequently at the centerpiece of much expert testimony about the reliability of eyewitness accounts. Although we have much knowledge about how false memories and suggestibility can affect testimonies, the contributions in this special issue show that when using a sound theoretical framework, novel directions in this field can surface. The papers in this issue can broadly be divided into contributions that are related to: (1) the exact determinants of false memory and suggestibility; (2) new paradigms in legal psychology; (3) positive consequences of memory illusions; and (4) developmental false memory research. Collectively, these contributions have the potential to provide novel shifts in memory research and push this field beyond its current boundaries. Copyright © 2013 John Wiley & Sons, Ltd.

Can Implicit Associations Distinguish True and False Eyewitness Memory? Development and Preliminary Testing of the IATe.

PubMed

Helm, Rebecca K; Ceci, Stephen J; Burd, Kayla A

2016-11-01

Eyewitness identification has been shown to be fallible and prone to false memory. In this study we develop and test a new method to probe the mechanisms involved in the formation of false memories in this area, and determine whether a particular memory is likely to be true or false. We created a seven-step procedure based on the Implicit Association Test to gauge implicit biases in eyewitness identification (the IATe). We show that identification errors may result from unconscious bias caused by implicit associations evoked by a given face. We also show that implicit associations between negative attributions such as guilt and eyewitnesses' final pick from a line-up can help to distinguish between true and false memory (especially where the witness has been subject to the suggestive nature of a prior blank line-up). Specifically, the more a witness implicitly associates an individual face with a particular crime, the more likely it is that a memory they have for that person committing the crime is false. These findings are consistent with existing findings in the memory and neuroscience literature showing that false memories can be caused by implicit associations that are outside conscious awareness. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

False Memory in Adults With ADHD: A Comparison Between Subtypes and Normal Controls.

PubMed

Soliman, Abdrabo Moghazy; Elfar, Rania Mohamed

2017-10-01

To examine the performance on the Deese-Roediger-McDermott task of adults divided into ADHD subtypes and compares their performance to that of healthy controls to examine whether adults with ADHD are more susceptible to the production of false memories under experimental conditions. A total of 128 adults with ADHD (50% females), classified into three Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV-TR) subtypes, were compared with 48 controls. The results indicated that the ADHD participants recalled and recognized fewer studied words than the controls, the ADHD groups produced more false memories than the control group, no differences in either the false positives or the false negatives. The ADHD-combined (ADHD-CT) group recognized significantly more critical words than the control, ADHD-predominantly inattentive (ADHD-IA), and ADHD-predominantly hyperactive-impulsive (ADHD-HI) groups. The ADHD groups recalled and recognized more false positives, were more confident in their false responses, and displayed more knowledge corruption than the controls. The ADHD-CT group recalled and recognized more false positives than the other ADHD groups. The adults with ADHD have more false memories than the controls and that false memory formation varied with the ADHD subtypes.

Effects of Presentation Format and List Length on Children's False Memories

ERIC Educational Resources Information Center

Swannell, Ellen R.; Dewhurst, Stephen A.

2013-01-01

The effect of list length on children's false memories was investigated using list and story versions of the Deese/Roediger-McDermott procedure. Short (7 items) and long (14 items) sequences of semantic associates were presented to children aged 6, 8, and 10 years old either in lists or embedded within a story that emphasized the list theme.…

Sleep enhances false memories depending on general memory performance.

PubMed

Diekelmann, Susanne; Born, Jan; Wagner, Ullrich

2010-04-02

Memory is subject to dynamic changes, sometimes giving rise to the formation of false memories due to biased processes of consolidation or retrieval. Sleep is known to benefit memory consolidation through an active reorganization of representations whereas acute sleep deprivation impairs retrieval functions. Here, we investigated whether sleep after learning and sleep deprivation at retrieval enhance the generation of false memories in a free recall test. According to the Deese, Roediger, McDermott (DRM) false memory paradigm, subjects learned lists of semantically associated words (e.g., "night", "dark", "coal", etc.), lacking the strongest common associate or theme word (here: "black"). Free recall was tested after 9h following a night of sleep, a night of wakefulness (sleep deprivation) or daytime wakefulness. Compared with memory performance after a retention period of daytime wakefulness, both post-learning nocturnal sleep as well as acute sleep deprivation at retrieval significantly enhanced false recall of theme words. However, these effects were only observed in subjects with low general memory performance. These data point to two different ways in which sleep affects false memory generation through semantic generalization: one acts during consolidation on the memory trace per se, presumably by active reorganization of the trace in the post-learning sleep period. The other is related to the recovery function of sleep and affects cognitive control processes of retrieval. Both effects are unmasked when the material is relatively weakly encoded. Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.

Inception of a false memory by optogenetic manipulation of a hippocampal memory engram.

PubMed

Liu, Xu; Ramirez, Steve; Tonegawa, Susumu

2014-01-05

Memories can be easily distorted, and a lack of relevant animal models has largely hindered our understanding of false-memory formation. Here, we first identified a population of cells in the dentate gyrus (DG) of the hippocampus that bear the engrams for a specific context; these cells were naturally activated during the encoding phase of fear conditioning and their artificial reactivation using optogenetics in an unrelated context was sufficient for inducing the fear memory specific to the conditioned context. In a further study, DG or CA1 neurons activated by exposure to a particular context were labelled with channelrhodopsin-2 (ChR2). These neurons were later optically reactivated during fear conditioning in a different context. The DG experimental group showed increased freezing in the original context in which a foot shock was never delivered. The recall of this false memory was context specific, activated similar downstream regions engaged during natural fear-memory recall, and was also capable of driving an active fear response. Together, our data demonstrate that by substituting a natural conditioned stimulus with optogenetically reactivated DG cells that bear contextual memory engrams, it is possible to incept an internally and behaviourally represented false fear memory.

Inception of a false memory by optogenetic manipulation of a hippocampal memory engram

PubMed Central

Liu, Xu; Ramirez, Steve; Tonegawa, Susumu

2014-01-01

Memories can be easily distorted, and a lack of relevant animal models has largely hindered our understanding of false-memory formation. Here, we first identified a population of cells in the dentate gyrus (DG) of the hippocampus that bear the engrams for a specific context; these cells were naturally activated during the encoding phase of fear conditioning and their artificial reactivation using optogenetics in an unrelated context was sufficient for inducing the fear memory specific to the conditioned context. In a further study, DG or CA1 neurons activated by exposure to a particular context were labelled with channelrhodopsin-2 (ChR2). These neurons were later optically reactivated during fear conditioning in a different context. The DG experimental group showed increased freezing in the original context in which a foot shock was never delivered. The recall of this false memory was context specific, activated similar downstream regions engaged during natural fear-memory recall, and was also capable of driving an active fear response. Together, our data demonstrate that by substituting a natural conditioned stimulus with optogenetically reactivated DG cells that bear contextual memory engrams, it is possible to incept an internally and behaviourally represented false fear memory. PMID:24298144

The impact of sleep on true and false memory across long delays.

PubMed

Pardilla-Delgado, Enmanuelle; Payne, Jessica D

2017-01-01

While the influence of sleep on memory has a long history, sleep's role in the formation of false memories is less clear. Moreover, virtually nothing is known about the development of false memories beyond delays of about 12h. Here, for the first time, we assess post-sleep development of true and false memories across longer delay intervals of 24 and 48h. Although technically a false memory, remembering information that is related to the theme, or gist, of an experience can be considered an adaptive process. Some evidence suggests that sleep, compared to a wake period, increases both true and gist-based false memories in the Deese-Roediger-McDermott (DRM) task, but not all studies have returned this result, and most studies cannot rule out the possibility that sleep is merely protecting the information from interference, as opposed to actively aiding its consolidation. Here, to equate amount of time spent awake and asleep across groups, we assess how the positioning of sleep relative to memory encoding impacts retention across longer delays of 24 and 48h. Participants encoded 16 DRM lists in the morning (WAKE 1st Groups) or evening (SLEEP 1st Groups), and were tested either 24 or 48h later at the same time of day. Results demonstrate that true memory is better when participants sleep soon after learning. Sleeping first also increased false memory, but only in low performers. Importantly, and similar to previous studies, we found a negative correlation between slow-wave sleep (SWS) and false memory, suggesting that SWS may be detrimental for semantic/gist processing. Copyright © 2016 Elsevier Inc. All rights reserved.

Semantic processes leading to true and false memory formation in schizophrenia.

PubMed

Paz-Alonso, Pedro M; Ghetti, Simona; Ramsay, Ian; Solomon, Marjorie; Yoon, Jong; Carter, Cameron S; Ragland, J Daniel

2013-07-01

Encoding semantic relationships between items on word lists (semantic processing) enhances true memories, but also increases memory distortions. Episodic memory impairments in schizophrenia (SZ) are strongly driven by failures to process semantic relations, but the exact nature of these relational semantic processing deficits is not well understood. Here, we used a false memory paradigm to investigate the impact of implicit and explicit semantic processing manipulations on episodic memory in SZ. Thirty SZ and 30 demographically matched healthy controls (HC) studied Deese/Roediger-McDermott (DRM) lists of semantically associated words. Half of the lists had strong implicit semantic associations and the remainder had low strength associations. Similarly, half of the lists were presented under "standard" instructions and the other half under explicit "relational processing" instructions. After study, participants performed recall and old/new recognition tests composed of targets, critical lures, and unrelated lures. HC exhibited higher true memories and better discriminability between true and false memory compared to SZ. High, versus low, associative strength increased false memory rates in both groups. However, explicit "relational processing" instructions positively improved true memory rates only in HC. Finally, true and false memory rates were associated with severity of disorganized and negative symptoms in SZ. These results suggest that reduced processing of semantic relationships during encoding in SZ may stem from an inability to implement explicit relational processing strategies rather than a fundamental deficit in the implicit activation and retrieval of word meanings from patients' semantic lexicon. Copyright © 2013 Elsevier B.V. All rights reserved.

What factors underlie children's susceptibility to semantic and phonological false memories? investigating the roles of language skills and auditory short-term memory.

PubMed

McGeown, Sarah P; Gray, Eleanor A; Robinson, Jamey L; Dewhurst, Stephen A

2014-06-01

Two experiments investigated the cognitive skills that underlie children's susceptibility to semantic and phonological false memories in the Deese/Roediger-McDermott procedure (Deese, 1959; Roediger & McDermott, 1995). In Experiment 1, performance on the Verbal Similarities subtest of the British Ability Scales (BAS) II (Elliott, Smith, & McCulloch, 1997) predicted correct and false recall of semantic lures. In Experiment 2, performance on the Yopp-Singer Test of Phonemic Segmentation (Yopp, 1988) did not predict correct recall, but inversely predicted the false recall of phonological lures. Auditory short-term memory was a negative predictor of false recall in Experiment 1, but not in Experiment 2. The findings are discussed in terms of the formation of gist and verbatim traces as proposed by fuzzy trace theory (Reyna & Brainerd, 1998) and the increasing automaticity of associations as proposed by associative activation theory (Howe, Wimmer, Gagnon, & Plumpton, 2009). Copyright © 2014 Elsevier B.V. All rights reserved.

Transient medial prefrontal perturbation reduces false memory formation.

PubMed

Berkers, Ruud M W J; van der Linden, Marieke; de Almeida, Rafael F; Müller, Nils C J; Bovy, Leonore; Dresler, Martin; Morris, Richard G M; Fernández, Guillén

2017-03-01

Knowledge extracted across previous experiences, or schemas, benefit encoding and retention of congruent information. However, they can also reduce specificity and augment memory for semantically related, but false information. A demonstration of the latter is given by the Deese-Roediger-McDermott (DRM) paradigm, where the studying of words that fit a common semantic schema are found to induce false memories for words that are congruent with the given schema, but were not studied. The medial prefrontal cortex (mPFC) has been ascribed the function of leveraging prior knowledge to influence encoding and retrieval, based on imaging and patient studies. Here, we used transcranial magnetic stimulation (TMS) to transiently perturb ongoing mPFC processing immediately before participants performed the DRM-task. We observed the predicted reduction in false recall of critical lures after mPFC perturbation, compared to two control groups, whereas veridical recall and recognition memory performance remained similar across groups. These data provide initial causal evidence for a role of the mPFC in biasing the assimilation of new memories and their consolidation as a function of prior knowledge. Copyright © 2016 Elsevier Ltd. All rights reserved.

Age differences in false memory: The importance of retrieval monitoring processes and their modulation by memory quality.

PubMed

Fandakova, Yana; Sander, Myriam C; Grandy, Thomas H; Cabeza, Roberto; Werkle-Bergner, Markus; Shing, Yee Lee

2018-02-01

Older adults are more likely than younger adults to falsely recall past episodes that occurred differently or not at all. We examined whether older adults' propensity for false associative memory is related to declines in postretrieval monitoring processes and their modulation with varying memory representations. Younger (N = 20) and older adults (N = 32) studied and relearned unrelated scene-word pairs, followed by a final cued recall that was used to distribute the pairs for an associative recognition test 24 hours later. This procedure allowed individualized formation of rearranged pairs that were made up of elements of pairs that were correctly recalled in the final cued recall ("high-quality" pairs), and of pairs that were not correctly recalled ("low-quality" pairs). Both age groups falsely recognized more low-quality than high-quality rearranged pairs, with a less pronounced reduction in false alarms to high-quality pairs in older adults. In younger adults, cingulo-opercular activity was enhanced for false alarms and for low-quality correct rejections, consistent with its role in postretrieval monitoring. Older adults did not show such modulated recruitment, suggesting deficits in their selective engagement of monitoring processes given variability in the fidelity of memory representations. There were no age differences in hippocampal activity, which was higher for high-quality than low-quality correct rejections in both age groups. These results demonstrate that the engagement of cingulo-opercular monitoring mechanisms varies with memory representation quality and contributes to age-related deficits in false associative memory. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Stress and emotional valence effects on children's versus adolescents' true and false memory.

PubMed

Quas, Jodi A; Rush, Elizabeth B; Yim, Ilona S; Edelstein, Robin S; Otgaar, Henry; Smeets, Tom

2016-01-01

Despite considerable interest in understanding how stress influences memory accuracy and errors, particularly in children, methodological limitations have made it difficult to examine the effects of stress independent of the effects of the emotional valence of to-be-remembered information in developmental populations. In this study, we manipulated stress levels in 7-8- and 12-14-year-olds and then exposed them to negative, neutral, and positive word lists. Shortly afterward, we tested their recognition memory for the words and false memory for non-presented but related words. Adolescents in the high-stress condition were more accurate than those in the low-stress condition, while children's accuracy did not differ across stress conditions. Also, among adolescents, accuracy and errors were higher for the negative than positive words, while in children, word valence was unrelated to accuracy. Finally, increases in children's and adolescents' cortisol responses, especially in the high-stress condition, were related to greater accuracy but not false memories and only for positive emotional words. Findings suggest that stress at encoding, as well as the emotional content of to-be-remembered information, may influence memory in different ways across development, highlighting the need for greater complexity in existing models of true and false memory formation.

Blunted cortisol response to acute pre-learning stress prevents misinformation effect in a forced confabulation paradigm.

PubMed

Zoladz, Phillip R; Cadle, Chelsea E; Dailey, Alison M; Fiely, Miranda K; Peters, David M; Nagle, Hannah E; Mosley, Brianne E; Scharf, Amanda R; Brown, Callie M; Duffy, Tessa J; Earley, McKenna B; Rorabaugh, Boyd R; Payment, Kristie E

2017-07-01

Research examining the effects of stress on false memory formation has been equivocal, partly because of the complex nature of stress-memory interactions. A major factor influencing stress effects on learning is the timing of stress relative to encoding. Previous work has shown that brief stressors administered immediately before learning enhance long-term memory. Thus, we predicted that brief stress immediately before learning would decrease participants' susceptibility to subsequent misinformation and reduce false memory formation. Eighty-four male and female participants submerged their hand in ice cold (stress) or warm (no stress) water for 3min. Immediately afterwards, they viewed an 8-min excerpt from the Disney movie Looking for Miracles. The next day, participants were interviewed and asked several questions about the video, some of which forced them to confabulate responses. Three days and three weeks later, respectively, participants completed a recognition test in the lab and a free recall test via email. Our results revealed a robust misinformation effect, overall, as participants falsely recognized a significant amount of information that they had confabulated during the interview as having occurred in the original video. Stress, overall, did not significantly influence this misinformation effect. However, the misinformation effect was completely absent in stressed participants who exhibited a blunted cortisol response to the stress, for both recognition and recall tests. The complete absence of a misinformation effect in non-responders may lend insight into the interactive roles of autonomic arousal and corticosteroid levels in false memory development. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of Presentation Mode on Veridical and False Memory in Individuals with Intellectual Disability

ERIC Educational Resources Information Center

Carlin, Michael; Toglia, Michael P.; Belmonte, Colleen; DiMeglio, Chiara

2012-01-01

In the present study the effects of visual, auditory, and audio-visual presentation formats on memory for thematically constructed lists were assessed in individuals with intellectual disability and mental age-matched children. The auditory recognition test included target items, unrelated foils, and two types of semantic lures: critical related…

A System for True and False Memory Prediction Based on 2D and 3D Educational Contents and EEG Brain Signals.

PubMed

Bamatraf, Saeed; Hussain, Muhammad; Aboalsamh, Hatim; Qazi, Emad-Ul-Haq; Malik, Amir Saeed; Amin, Hafeez Ullah; Mathkour, Hassan; Muhammad, Ghulam; Imran, Hafiz Muhammad

2016-01-01

We studied the impact of 2D and 3D educational contents on learning and memory recall using electroencephalography (EEG) brain signals. For this purpose, we adopted a classification approach that predicts true and false memories in case of both short term memory (STM) and long term memory (LTM) and helps to decide whether there is a difference between the impact of 2D and 3D educational contents. In this approach, EEG brain signals are converted into topomaps and then discriminative features are extracted from them and finally support vector machine (SVM) which is employed to predict brain states. For data collection, half of sixty-eight healthy individuals watched the learning material in 2D format whereas the rest watched the same material in 3D format. After learning task, memory recall tasks were performed after 30 minutes (STM) and two months (LTM), and EEG signals were recorded. In case of STM, 97.5% prediction accuracy was achieved for 3D and 96.6% for 2D and, in case of LTM, it was 100% for both 2D and 3D. The statistical analysis of the results suggested that for learning and memory recall both 2D and 3D materials do not have much difference in case of STM and LTM.

A System for True and False Memory Prediction Based on 2D and 3D Educational Contents and EEG Brain Signals

PubMed Central

2016-01-01

We studied the impact of 2D and 3D educational contents on learning and memory recall using electroencephalography (EEG) brain signals. For this purpose, we adopted a classification approach that predicts true and false memories in case of both short term memory (STM) and long term memory (LTM) and helps to decide whether there is a difference between the impact of 2D and 3D educational contents. In this approach, EEG brain signals are converted into topomaps and then discriminative features are extracted from them and finally support vector machine (SVM) which is employed to predict brain states. For data collection, half of sixty-eight healthy individuals watched the learning material in 2D format whereas the rest watched the same material in 3D format. After learning task, memory recall tasks were performed after 30 minutes (STM) and two months (LTM), and EEG signals were recorded. In case of STM, 97.5% prediction accuracy was achieved for 3D and 96.6% for 2D and, in case of LTM, it was 100% for both 2D and 3D. The statistical analysis of the results suggested that for learning and memory recall both 2D and 3D materials do not have much difference in case of STM and LTM. PMID:26819593

Implicit face prototype learning from geometric information.

PubMed

Or, Charles C-F; Wilson, Hugh R

2013-04-19

There is evidence that humans implicitly learn an average or prototype of previously studied faces, as the unseen face prototype is falsely recognized as having been learned (Solso & McCarthy, 1981). Here we investigated the extent and nature of face prototype formation where observers' memory was tested after they studied synthetic faces defined purely in geometric terms in a multidimensional face space. We found a strong prototype effect: The basic results showed that the unseen prototype averaged from the studied faces was falsely identified as learned at a rate of 86.3%, whereas individual studied faces were identified correctly 66.3% of the time and the distractors were incorrectly identified as having been learned only 32.4% of the time. This prototype learning lasted at least 1 week. Face prototype learning occurred even when the studied faces were further from the unseen prototype than the median variation in the population. Prototype memory formation was evident in addition to memory formation of studied face exemplars as demonstrated in our models. Additional studies showed that the prototype effect can be generalized across viewpoints, and head shape and internal features separately contribute to prototype formation. Thus, implicit face prototype extraction in a multidimensional space is a very general aspect of geometric face learning. Copyright © 2013 Elsevier Ltd. All rights reserved.

Emotional false memories in children with learning disabilities.

PubMed

Mirandola, Chiara; Losito, Nunzia; Ghetti, Simona; Cornoldi, Cesare

2014-02-01

Research has shown that children with learning disabilities (LD) are less prone to evince associative illusions of memory as a result of impairments in their ability to engage in semantic processing. However, it is unclear whether this observation is true for scripted life events, especially if they include emotional content, or across a broad spectrum of learning disabilities. The present study addressed these issues by assessing recognition memory for script-like information in children with nonverbal learning disability (NLD), children with dyslexia, and typically developing children (N=51). Participants viewed photographs about 8 common events (e.g., family dinner), and embedded in each episode was either a negative or a neutral consequence of an unseen action. Children's memory was then tested on a yes/no recognition task that included old and new photographs. Results showed that the three groups performed similarly in recognizing target photographs, but exhibited differences in memory errors. Compared to other groups, children with NLD were more likely to falsely recognize photographs that depicted an unseen cause of an emotional seen event and associated more "Remember" responses to these errors. Children with dyslexia were equally likely to falsely recognize both unseen causes of seen photographs and photographs generally consistent with the script, whereas the other participant groups were more likely to falsely recognize unseen causes rather than script-consistent distractors. Results are interpreted in terms of mechanisms underlying false memories' formation in different clinical populations of children with LD. Copyright © 2013 Elsevier Ltd. All rights reserved.

The parietal memory network activates similarly for true and associative false recognition elicited via the DRM procedure.

PubMed

McDermott, Kathleen B; Gilmore, Adrian W; Nelson, Steven M; Watson, Jason M; Ojemann, Jeffrey G

2017-02-01

Neuroimaging investigations of human memory encoding and retrieval have revealed that multiple regions of parietal cortex contribute to memory. Recently, a sparse network of regions within parietal cortex has been identified using resting state functional connectivity (MRI techniques). The regions within this network exhibit consistent task-related responses during memory formation and retrieval, leading to its being called the parietal memory network (PMN). Among its signature patterns are: deactivation during initial experience with an item (e.g., encoding); activation during subsequent repetitions (e.g., at retrieval); greater activation for successfully retrieved familiar words than novel words (e.g., hits relative to correctly-rejected lures). The question of interest here is whether novel words that are subjectively experienced as having been recently studied would elicit PMN activation similar to that of hits. That is, we compared old items correctly recognized to two types of novel items on a recognition test: those correctly identified as new and those incorrectly labeled as old due to their strong associative relation to the studied words (in the DRM false memory protocol). Subjective oldness plays a strong role in driving activation, as hits and false alarms activated similarly (and greater than correctly-rejected lures). Copyright © 2016 Elsevier Ltd. All rights reserved.

Destination memory accuracy and confidence in younger and older adults.

PubMed

Johnson, Tara L; Jefferson, Susan C

2018-01-01

Background/Study Context: Nascent research on destination memory-remembering to whom we tell particular information-suggested that older adults have deficits in destination memory and are more confident on inaccurate responses than younger adults. This study assessed the effects of age, attentional resources, and mental imagery on destination memory accuracy and confidence in younger and older adults. Using computer format, participants told facts to pictures of famous people in one of four conditions (control, self-focus, refocus, imagery). Older adults had lower destination memory accuracy than younger adults, driven by a higher level of false alarms. Whereas younger adults were more confident in accurate answers, older adults were more confident in inaccurate answers. Accuracy across participants was lowest when attention was directed internally but significantly improved when mental imagery was used. Importantly, the age-related differences in false alarms and high-confidence inaccurate answers disappeared when imagery was used. Older adults are more likely than younger adults to commit destination memory errors and are less accurate in related confidence judgments. Furthermore, the use of associative memory strategies may help improve destination memory across age groups, improve the accuracy of confidence judgments in older adults, and decrease age-related destination memory impairment, particularly in young-old adults.

False recall in the Deese–Roediger–McDermott paradigm: The roles of gist and associative strength

PubMed Central

Cann, David R.; McRae, Ken; Katz, Albert N.

2011-01-01

Theories of false memories, particularly in the Deese–Roediger–McDermott (DRM) paradigm, focus on word association strength and gist. Backward associative strength (BAS) is a strong predictor of false recall in this paradigm. However, other than being defined as a measure of association between studied list words and falsely recalled nonpresented critical words, there is little understanding of this variable. In Experiment 1, we used a knowledge-type taxonomy to classify the semantic relations in DRM stimuli. These knowledge types predicted false-recall probability, as well as BAS itself, with the most important being situation features, synonyms, and taxonomic relations. In three subsequent experiments, we demonstrated that lists composed solely of situation features can elicit a gist and produce false memories, particularly when monitoring processes are made more difficult. Our results identify the semantic factors that underlie BAS and suggest how considering semantic relations leads to a better understanding of gist formation. PMID:21506047

Children's episodic memory.

PubMed

Ghetti, Simona; Lee, Joshua

2011-07-01

Episodic memory develops during childhood and adolescence. This trajectory depends on several underlying processes. In this article, we first discuss the development of the basic binding processes (e.g., the processes by which elements are bound together to form a memory episode) and control processes (e.g., reasoning and metamemory processes) involved in episodic remembering. Then, we discuss the role of these processes in false-memory formation. In the subsequent sections, we examine the neural substrates of the development of episodic memory. Finally, we discuss atypical development of episodic memory. As we proceed through the article, we suggest potential avenues for future research. WIREs Cogni Sci 2011 2 365-373 DOI: 10.1002/wcs.114 For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

Temporal and visual source memory deficits among ecstasy/polydrug users.

PubMed

Fisk, John E; Gallagher, Denis T; Hadjiefthyvoulou, Florentia; Montgomery, Catharine

2014-03-01

We wished to investigate whether source memory judgements are adversely affected by recreational illicit drug use. Sixty-two ecstasy/polydrug users and 75 non ecstasy users completed a source memory task, in which they tried to determine whether or not a word had been previously presented and if so, attempted to recall the format, location and temporal position in which the word had occurred. While not differing in terms of the number of hits and false positive responses, ecstasy/polydrug users adopted a more liberal decision criterion when judging if a word had been presented previously. With regard to source memory, users were less able to determine the format in which words had been presented (upper versus lower case). Female users did worse than female nonusers in determining which list (first or second) a word was from. Unexpectedly, the current frequency of cocaine use was negative associated with list and case source memory performance. Given the role that source memory plays in everyday cognition, those who use cocaine more frequently might have more difficulty in everyday tasks such as recalling the sources of crucial information or making use of contextual information as an aid to learning.

Mechanisms underlying the production of false memories for famous people's names in aging and Alzheimer's disease.

PubMed

Plancher, Gaën; Guyard, Anne; Nicolas, Serge; Piolino, Pascale

2009-10-01

It is well known that the occurrence of false memories increases with aging, but the results remain inconsistent concerning Alzheimer's disease (AD). Moreover, the mechanisms underlying the production of false memories are still unclear. Using an experimental episodic memory test with material based on the names of famous people in a procedure derived from the DRM paradigm [Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory & Cognition, 21, 803-814], we examined correct and false recall and recognition in 30 young adults, 40 healthy older adults, and 30 patients with AD. Moreover, we evaluated the relationships between false memory performance, correct episodic memory performance, and a set of neuropsychological assessments evaluating the semantic memory and executive functions. The results clearly indicated that correct recall and recognition performance decreased with the subjects' age, but it decreased even more with AD. In addition, semantically related false recalls and false recognitions increased with age but not with dementia. On the contrary, non-semantically related false recalls and false recognitions increased with AD. Finally, the regression analyses showed that executive functions mediated related false memories and episodic memory mediated related and unrelated false memories in aging. Moreover, executive functions predicted related and unrelated false memories in AD, and episodic and semantic memory predicted semantically related and unrelated false memories in AD. In conclusion, the results obtained are consistent with the current constructive models of memory suggesting that false memory creation depends on different cognitive functions and, consequently, that the impairments of these functions influence the production of false memories.

Social influence and mental routes to the production of authentic false memories and inauthentic false memories.

PubMed

Wagner, Michael F; Skowronski, John J

2017-05-01

Two studies assessed the extent to which people incorporated false facts provided by bogus others into their own recognition memory reports, and how these false memory reports were affected by: (a) truth of the information in others' summaries supporting the false facts, (b) motivation to process stories and summaries, (c) source credibility, and (d) ease of remembering original facts. False memory report frequency increased when false facts in a summary were supported by true information and varied inversely with the ease with which original facts could be remembered. Results from a measure probing participants' memory perceptions suggest that some false memories are authentic: People sometimes lack awareness of both the incorporation of false facts into their memory reports and where the false facts came from. However, many false memories are inauthentic: Despite reporting a false memory, people sometimes retain knowledge of the original stimulus and/or the origin of false facts. Copyright © 2017. Published by Elsevier Inc.

False memories for aggressive acts.

PubMed

Laney, Cara; Takarangi, Melanie K T

2013-06-01

Can people develop false memories for committing aggressive acts? How does this process compare to developing false memories for victimhood? In the current research we used a simple false feedback procedure to implant false memories for committing aggressive acts (causing a black eye or spreading malicious gossip) or for victimhood (receiving a black eye). We then compared these false memories to other subjects' true memories for equivalent events. False aggressive memories were all too easy to implant, particularly in the minds of individuals with a proclivity towards aggression. Once implanted, the false memories were indistinguishable from true memories for the same events, on several dimensions, including emotional content. Implications for aggression-related memory more generally as well as false confessions are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

The origin of children's implanted false memories: memory traces or compliance?

PubMed

Otgaar, Henry; Verschuere, Bruno; Meijer, Ewout H; van Oorsouw, Kim

2012-03-01

A longstanding question in false memory research is whether children's implanted false memories represent actual memory traces or merely result from compliance. The current study examined this question using a response latency based deception task. Forty-five 8-year-old children received narratives about a true (first day at school) and false event (hot air balloon ride). Across two interviews, 58/32% of the participants developed a partial/full false memory. Interestingly, these children also showed higher false recall on an unrelated DRM paradigm compared to children without a false memory. The crucial finding, however, was that the results of the deception task revealed that children with partial and full false memories were faster to confirm than to deny statements relating to the false event. This indicates that children's implanted false memories reflect actual memory traces, and are unlikely to be explained by mere compliance. Copyright © 2012 Elsevier B.V. All rights reserved.

Maltreatment increases spontaneous false memories but decreases suggestion-induced false memories in children.

PubMed

Otgaar, Henry; Howe, Mark L; Muris, Peter

2017-09-01

We examined the creation of spontaneous and suggestion-induced false memories in maltreated and non-maltreated children. Maltreated and non-maltreated children were involved in a Deese-Roediger-McDermott false memory paradigm where they studied and remembered negative and neutral word lists. Suggestion-induced false memories were created using a misinformation procedure during which both maltreated and non-maltreated children viewed a negative video (i.e., bank robbery) and later received suggestive misinformation concerning the event. Our results showed that maltreated children had higher levels of spontaneous negative false memories but lower levels of suggestion-induced false memories as compared to non-maltreated children. Collectively, our study demonstrates that maltreatment both increases and decreases susceptibility to memory illusions depending on the type of false memory being induced. Statement of contribution What is already known on this subject? Trauma affects memory. It is unclear how trauma affects false memory. What does this study add? This study focuses on two types of false memories. © 2017 The Authors. British Journal of Developmental Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

Time dependent effects of stress prior to encoding on event-related potentials and 24 h delayed retrieval.

PubMed

Quaedflieg, Conny W E M; Schwabe, Lars; Meyer, Thomas; Smeets, Tom

2013-12-01

Stress can exert profound effects on memory encoding. Here, we investigated whether (sub)cortical information processing during encoding and memory retrieval at a 24 h delayed test are affected by the temporal proximity between stress and memory encoding. Sixty-four participants engaged in the Maastricht Acute Stress Test (MAST) or a no-stress control condition either immediately before (i.e., proximate condition) or 30 min before (i.e., distant condition) a picture encoding task. In general, stress decreased the number of freely recalled and recognized pictures and increased the number of false alarms. However, timing of stress exposure did not differentially affect picture recall, recognition or selective attention processes (i.e., LPP). Nevertheless, stress-induced cortisol responses and correctly recognized neutral pictures were positively associated within the proximate stress condition but negatively associated within the distant stress condition. These findings suggest that the time at which a stressor is applied might differentially impact the association between stress-induced cortisol elevations and memory formation and indicate the need for a finer delineation of the time window during which glucocorticoids affect memory formation processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Developmental reversals in false memory: now you see them, now you don't!

PubMed

Holliday, Robyn E; Brainerd, Charles J; Reyna, Valerie F

2011-03-01

A developmental reversal in false memory is the counterintuitive phenomenon of higher levels of false memory in older children, adolescents, and adults than in younger children. The ability of verbatim memory to suppress this age trend in false memory was evaluated using the Deese-Roediger-McDermott (DRM) paradigm. Seven and 11-year-old children studied DRM lists either in a standard condition (whole words) that normally produces high levels of false memory or in an alternative condition that should enhance verbatim memory (word fragments). Half the children took 1 recognition test, and the other half took 3 recognition tests. In the single-test condition, the typical age difference in false memory was found for the word condition (higher false memory for 11-year-olds than for 7-year-olds), but in the word fragment condition false memory was lower in the older children. In the word condition, false memory increased over successive recognition tests. Our findings are consistent with 2 principles of fuzzy-trace theory's explanation of false memories: (a) reliance on verbatim rather than gist memory causes such errors to decline with age, and (b) repeated testing increases reliance on gist memory in older children and adults who spontaneously connect meaning across events. PsycINFO Database Record (c) 2011 APA, all rights reserved.

The cortical basis of true memory and false memory for motion.

PubMed

Karanian, Jessica M; Slotnick, Scott D

2014-02-01

Behavioral evidence indicates that false memory, like true memory, can be rich in sensory detail. By contrast, there is fMRI evidence that true memory for visual information produces greater activity in earlier visual regions than false memory, which suggests true memory is associated with greater sensory detail. However, false memory in previous fMRI paradigms may have lacked sufficient sensory detail to recruit earlier visual processing regions. To investigate this possibility in the present fMRI study, we employed a paradigm that produced feature-specific false memory with a high degree of visual detail. During the encoding phase, moving or stationary abstract shapes were presented to the left or right of fixation. During the retrieval phase, shapes from encoding were presented at fixation and participants classified each item as previously "moving" or "stationary" within each visual field. Consistent with previous fMRI findings, true memory but not false memory for motion activated motion processing region MT+, while both true memory and false memory activated later cortical processing regions. In addition, false memory but not true memory for motion activated language processing regions. The present findings indicate that true memory activates earlier visual regions to a greater degree than false memory, even under conditions of detailed retrieval. Thus, the dissociation between previous behavioral findings and fMRI findings do not appear to be task dependent. Future work will be needed to assess whether the same pattern of true memory and false memory activity is observed for different sensory modalities. Copyright © 2013 Elsevier Ltd. All rights reserved.

True and false memories, parietal cortex, and confidence judgments

PubMed Central

Urgolites, Zhisen J.; Smith, Christine N.

2015-01-01

Recent studies have asked whether activity in the medial temporal lobe (MTL) and the neocortex can distinguish true memory from false memory. A frequent complication has been that the confidence associated with correct memory judgments (true memory) is typically higher than the confidence associated with incorrect memory judgments (false memory). Accordingly, it has often been difficult to know whether a finding is related to memory confidence or memory accuracy. In the current study, participants made recognition memory judgments with confidence ratings in response to previously studied scenes and novel scenes. The left hippocampus and 16 other brain regions distinguished true and false memories when confidence ratings were different for the two conditions. Only three regions (all in the parietal cortex) distinguished true and false memories when confidence ratings were equated. These findings illustrate the utility of taking confidence ratings into account when identifying brain regions associated with true and false memories. Neural correlates of true and false memories are most easily interpreted when confidence ratings are similar for the two kinds of memories. PMID:26472645

Social Transmission of False Memory in Small Groups and Large Networks.

PubMed

Maswood, Raeya; Rajaram, Suparna

2018-05-21

Sharing information and memories is a key feature of social interactions, making social contexts important for developing and transmitting accurate memories and also false memories. False memory transmission can have wide-ranging effects, including shaping personal memories of individuals as well as collective memories of a network of people. This paper reviews a collection of key findings and explanations in cognitive research on the transmission of false memories in small groups. It also reviews the emerging experimental work on larger networks and collective false memories. Given the reconstructive nature of memory, the abundance of misinformation in everyday life, and the variety of social structures in which people interact, an understanding of transmission of false memories has both scientific and societal implications. © 2018 Cognitive Science Society, Inc.

Retrieval monitoring and anosognosia in Alzheimer's disease.

PubMed

Gallo, David A; Chen, Jennifer M; Wiseman, Amy L; Schacter, Daniel L; Budson, Andrew E

2007-09-01

This study explored the relationship between episodic memory and anosognosia (a lack of deficit awareness) among patients with mild Alzheimer's disease (AD). Participants studied words and pictures for subsequent memory tests. Healthy older adults made fewer false recognition errors when trying to remember pictures compared with words, suggesting that the perceptual distinctiveness of picture memories enhanced retrieval monitoring (the distinctiveness heuristic). In contrast, although participants with AD could discriminate between studied and nonstudied items, they had difficulty recollecting the specific presentation formats (words or pictures), and they had limited use of the distinctiveness heuristic. Critically, the demands of the memory test modulated the relationship between memory accuracy and anosognosia. Greater anosognosia was associated with impaired memory accuracy when participants with AD tried to remember words but not when they tried to remember pictures. These data further delineate the retrieval monitoring difficulties among individuals with AD and suggest that anosognosia measures are most likely to correlate with memory tests that require the effortful retrieval of nondistinctive information. (PsycINFO Database Record (c) 2007 APA, all rights reserved).

Working memory affects false memory production for emotional events.

PubMed

Mirandola, Chiara; Toffalini, Enrico; Ciriello, Alfonso; Cornoldi, Cesare

2017-01-01

Whereas a link between working memory (WM) and memory distortions has been demonstrated, its influence on emotional false memories is unclear. In two experiments, a verbal WM task and a false memory paradigm for negative, positive or neutral events were employed. In Experiment 1, we investigated individual differences in verbal WM and found that the interaction between valence and WM predicted false recognition, with negative and positive material protecting high WM individuals against false remembering; the beneficial effect of negative material disappeared in low WM participants. In Experiment 2, we lowered the WM capacity of half of the participants with a double task request, which led to an overall increase in false memories; furthermore, consistent with Experiment 1, the increase in negative false memories was larger than that of neutral or positive ones. It is concluded that WM plays a critical role in determining false memory production, specifically influencing the processing of negative material.

Importing perceived features into false memories.

PubMed

Lyle, Keith B; Johnson, Marcia K

2006-02-01

False memories sometimes contain specific details, such as location or colour, about events that never occurred. Based on the source-monitoring framework, we investigated one process by which false memories acquire details: the reactivation and misattribution of feature information from memories of similar perceived events. In Experiments 1A and 1B, when imagined objects were falsely remembered as seen, participants often reported that the objects had appeared in locations where visually or conceptually similar objects, respectively, had actually appeared. Experiment 2 indicated that colour and shape features of seen objects were misattributed to false memories of imagined objects. Experiment 3 showed that perceived details were misattributed to false memories of objects that had not been explicitly imagined. False memories that imported perceived features, compared to those that presumably did not, were subjectively more like memories for perceived events. Thus, perception may be even more pernicious than imagination in contributing to false memories.

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

PubMed

Porter, Stephen; Taylor, Kristian; Ten Brinke, Leanne

2008-01-01

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

Psychoactive drugs and false memory: comparison of dextroamphetamine and delta-9-tetrahydrocannabinol on false recognition

PubMed Central

Ballard, Michael E.; Gallo, David A.; de Wit, Harriet

2014-01-01

Rationale Several psychoactive drugs are known to influence episodic memory. However, these drugs’ effects on false memory, or the tendency to incorrectly remember nonstudied information, remain poorly understood. Objectives Here, we examined the effects of two commonly used psychoactive drugs, one with memory-enhancing properties (dextroamphetamine; AMP), and another with memory-impairing properties (Δ9-tetrahydrocannabinol; THC), on false memory using the Deese/Roediger–McDermott (DRM) illusion. Methods Two parallel studies were conducted in which healthy volunteers received either AMP (0, 10, and 20 mg) or THC (0, 7.5, and 15 mg) in within-subjects, randomized, double-blind designs. Participants studied DRM word lists under the influence of the drugs, and their recognition memory for the studied words was tested 2 days later, under sober conditions. Results As expected, AMP increased memory of studied words relative to placebo, and THC reduced memory of studied words. Although neither drug significantly affected false memory relative to placebo, AMP increased false memory relative to THC. Across participants, both drugs’ effects on true memory were positively correlated with their effects on false memory. Conclusions Our results indicate that AMP and THC have opposing effects on true memory, and these effects appear to correspond to similar, albeit more subtle, effects on false memory. These findings are consistent with previous research using the DRM illusion and provide further evidence that psychoactive drugs can affect the encoding processes that ultimately result in the creation of false memories. PMID:21647577

Psychoactive drugs and false memory: comparison of dextroamphetamine and δ-9-tetrahydrocannabinol on false recognition.

PubMed

Ballard, Michael E; Gallo, David A; de Wit, Harriet

2012-01-01

Several psychoactive drugs are known to influence episodic memory. However, these drugs' effects on false memory, or the tendency to incorrectly remember nonstudied information, remain poorly understood. Here, we examined the effects of two commonly used psychoactive drugs, one with memory-enhancing properties (dextroamphetamine; AMP), and another with memory-impairing properties (Δ(9)-tetrahydrocannabinol; THC), on false memory using the Deese/Roediger-McDermott (DRM) illusion. Two parallel studies were conducted in which healthy volunteers received either AMP (0, 10, and 20 mg) or THC (0, 7.5, and 15 mg) in within-subjects, randomized, double-blind designs. Participants studied DRM word lists under the influence of the drugs, and their recognition memory for the studied words was tested 2 days later, under sober conditions. As expected, AMP increased memory of studied words relative to placebo, and THC reduced memory of studied words. Although neither drug significantly affected false memory relative to placebo, AMP increased false memory relative to THC. Across participants, both drugs' effects on true memory were positively correlated with their effects on false memory. Our results indicate that AMP and THC have opposing effects on true memory, and these effects appear to correspond to similar, albeit more subtle, effects on false memory. These findings are consistent with previous research using the DRM illusion and provide further evidence that psychoactive drugs can affect the encoding processes that ultimately result in the creation of false memories.

The false memory syndrome: Experimental studies and comparison to confabulations

PubMed Central

Mendez, M.F.; Fras, I.A.

2011-01-01

False memories, or recollections that are factually incorrect but strongly believed, remain a source of confusion for both psychiatrists and neurologists. We propose model for false memories based on recent experimental investigations, particularly when analyzed in comparison to confabulations, which are the equivalent of false memories from neurological disease. Studies using the Deese/Roedinger–McDermott experimental paradigm indicate that false memories are associated with the need for complete and integrated memories, self-relevancy, imagination and wish fulfillment, familiarity, emotional facilitation, suggestibility, and sexual content. In comparison, confabulations are associated with the same factors except for emotional facilitation, suggestibility, and sexual content. Both false memories and confabulations have an abnormal sense of certainty for their recollections, and neuroanatomical findings implicate decreased activity in the ventromedial frontal lobe in this certainty. In summary, recent studies of false memories in comparison to confabulations support a model of false memories as internally-generated but suggestible and emotionally-facilitated fantasies or impulses, rather than repressed memories of real events. Furthermore, like confabulations, in order for false memories to occur there must be an attenuation of the normal, nonconscious, right frontal “doubt tag” regarding their certainty. PMID:21177042

[Neuropsychological study of false memory in patients with amnesia mild cognitive impairment].

PubMed

Xie, Dan-dan; Cheng, Huai-dong; Yin, Chang-lin; Lü, Xin-yi; Wang, Kai

2011-01-18

To explore the profile of false memory in aMCI (amnesia mild cognitive impairment) and to elucidate the neuropsychological mechanism of false memory. False memory provoked by pictures and feeling-of-knowing (FOK) test in episodic memory (EM) were conducted in 25 aMCI patients at our hospital from October 2009 to May 2010. And 25 age and education level-matched healthy patients were recruited into the healthy control (HC) group. As compared with HC group, the rate of false memory was higher in the aMCI group. The rate of false memory in recall stage was 26% ± 7% and that of questionnaire stage 28% ± 12%. And the difference between two group was significant (t = 14.437, 7.597, P < 0.05). The FOK-EM of correct judgment and false recognition in the aMCI group (41% ± 10%) was higher than the HC group. And the difference was significant (t = 4.207, P < 0.05). The rates of false memory in recall and questionnaire stages were positively correlated with FOK-EM in aMCI group (r = 0.563, 0.705, P < 0.01). The aMCI patients tend to have more false memory provoked by pictures. The deficit of memory monitoring in aMCI may be the foundation of false memory.

True memory, false memory, and subjective recollection deficits after focal parietal lobe lesions.

PubMed

Drowos, David B; Berryhill, Marian; André, Jessica M; Olson, Ingrid R

2010-07-01

There is mounting evidence that the posterior parietal cortex (PPC) plays an important role in episodic memory. We previously found that patients with PPC damage exhibit retrieval-related episodic memory deficits. Here we assess whether parietal lobe damage affects episodic memory on a different task: the Deese-Roediger-McDermott (DRM) false-memory paradigm. Two patients with bilateral PPC damage and a group of matched controls were tested. In Experiment 1, the task was to remember words; in Experiment 2 the task was to remember pictures of common objects. Prior studies have shown that normal participants have high levels of false memory to words, low levels to pictures. The patients exhibited significantly lower levels of false memory to words. One patient showed significantly elevated levels of false memory to pictures. The patients' false memories were accompanied by reduced levels of recollection, as tested by a Remember/Know procedure. PPC damage causes decreased levels of false memories and an abnormal Remember/Know profile. Their false memory rate is similar to the rate exhibited by patients with medial temporal lobe damage. These results support the view that portions of the PPC play a critical role in objective and subjective aspects of recollection.

False Memories for Suggestions: The Impact of Conceptual Elaboration

PubMed Central

Zaragoza, Maria S.; Mitchell, Karen J.; Payment, Kristie; Drivdahl, Sarah

2010-01-01

Relatively little attention has been paid to the potential role that reflecting on the meaning and implications of suggested events (i.e., conceptual elaboration) might play in promoting the creation of false memories. Two experiments assessed whether encouraging repeated conceptual elaboration, would, like perceptual elaboration, increase false memory for suggested events. Results showed that conceptual elaboration of suggested events more often resulted in high confidence false memories (Experiment 1) and false memories that were accompanied by the phenomenal experience of remembering them (Experiment 2) than did surface-level processing. Moreover, conceptual elaboration consistently led to higher rates of false memory than did perceptual elaboration. The false memory effects that resulted from conceptual elaboration were highly dependent on the organization of the postevent interview questions, such that conceptual elaboration only increased false memory beyond surface level processing when participants evaluated both true and suggested information in relation to the same theme or dimension. PMID:21103451

Are subjective memory problems related to suggestibility, compliance, false memories, and objective memory performance?

PubMed

Van Bergen, Saskia; Jelicic, Marko; Merckelbach, Harald

2009-01-01

The relationship between subjective memory beliefs and suggestibility, compliance, false memories, and objective memory performance was studied in a community sample of young and middle-aged people (N = 142). We hypothesized that people with subjective memory problems would exhibit higher suggestibility and compliance levels and would be more susceptible to false recollections than those who are optimistic about their memory. In addition, we expected a discrepancy between subjective memory judgments and objective memory performance. We found that subjective memory judgments correlated significantly with compliance, with more negative memory judgments accompanying higher levels of compliance. Contrary to our expectation, subjective memory problems did not correlate with suggestibility or false recollections. Furthermore, participants were accurate in estimating their objective memory performance.

True and False Memories, Parietal Cortex, and Confidence Judgments

ERIC Educational Resources Information Center

Urgolites, Zhisen J.; Smith, Christine N.; Squire, Larry R.

2015-01-01

Recent studies have asked whether activity in the medial temporal lobe (MTL) and the neocortex can distinguish true memory from false memory. A frequent complication has been that the confidence associated with correct memory judgments (true memory) is typically higher than the confidence associated with incorrect memory judgments (false memory).…

How Fuzzy-Trace Theory Predicts True and False Memories for Words, Sentences, and Narratives

PubMed Central

Reyna, Valerie F.; Corbin, Jonathan C.; Weldon, Rebecca B.; Brainerd, Charles J.

2016-01-01

Fuzzy-trace theory posits independent verbatim and gist memory processes, a distinction that has implications for such applied topics as eyewitness testimony. This distinction between precise, literal verbatim memory and meaning-based, intuitive gist accounts for memory paradoxes including dissociations between true and false memory, false memories outlasting true memories, and developmental increases in false memory. We provide an overview of fuzzy-trace theory, and, using mathematical modeling, also present results demonstrating verbatim and gist memory in true and false recognition of narrative sentences and inferences. Results supported fuzzy-trace theory's dual-process view of memory: verbatim memory was relied on to reject meaning-consistent, but unpresented, sentences (via recollection rejection). However, verbatim memory was often not retrieved, and gist memory supported acceptance of these sentences (via similarity judgment and phantom recollection). Thus, mathematical models of words can be extended to explain memory for complex stimuli, such as narratives, the kind of memory interrogated in law. PMID:27042402

Explaining the Development of False Memories.

ERIC Educational Resources Information Center

Reyna, Valerie F.; Holliday, Robyn; Marche, Tammy

2002-01-01

Reviews explanatory dimensions of children's false memory relevant to forensic practice: measurement, development, social factors, individual differences, varieties of memories and memory judgments, and varieties of procedures inducing false memories. Asserts that recent studies fail to use techniques that separate acquiescence from memory…

Affect influences false memories at encoding: evidence from recognition data.

PubMed

Storbeck, Justin; Clore, Gerald L

2011-08-01

Memory is susceptible to illusions in the form of false memories. Prior research found, however, that sad moods reduce false memories. The current experiment had two goals: (1) to determine whether affect influences retrieval processes, and (2) to determine whether affect influences the strength and the persistence of false memories. Happy or sad moods were induced either before or after learning word lists designed to produce false memories. Control groups did not experience a mood induction. We found that sad moods reduced false memories only when induced before learning. Signal detection analyses confirmed that sad moods induced prior to learning reduced activation of nonpresented critical lures suggesting that they came to mind less often. Affective states, however, did not influence retrieval effects. We conclude that negative affective states promote item-specific processing, which reduces false memories in a similar way as using an explicitly guided cognitive control strategy. 2011 APA, all rights reserved

Affect Influences False Memories at Encoding: Evidence from Recognition Data

PubMed Central

Storbeck, Justin; Clore, Gerald L.

2014-01-01

Memory is susceptible to illusions in the form of false memories. Prior research found, however, that sad moods reduce false memories. The current experiment had two goals: (1) to determine whether affect influences retrieval processes, and (2) to determine whether affect influences the strength and the persistence of false memories. Happy or sad moods were induced either before or after learning word lists designed to produce false memories. Control groups did not experience a mood induction. We found that sad moods reduced false memories only when induced before learning. Signal detection analyses confirmed that sad moods induced prior to learning reduced activation of nonpresented critical lures suggesting that they came to mind less often. Affective states, however, did not influence retrieval effects. We conclude that negative affective states promote item-specific processing, which reduces false memories in a similar way as using an explicitly guided cognitive control strategy. PMID:21517165

Effects of Sulpiride on True and False Memories of Thematically Related Pictures and Associated Words in Healthy Volunteers

PubMed Central

Guarnieri, Regina V.; Ribeiro, Rafaela L.; de Souza, Altay A. Lino; Galduróz, José Carlos F.; Covolan, Luciene; Bueno, Orlando F. A.

2016-01-01

Episodic memory, working memory, emotional memory, and attention are subject to dopaminergic modulation. However, the potential role of dopamine on the generation of false memories is unknown. This study defined the role of the dopamine D2 receptor on true and false recognition memories. Twenty-four young, healthy volunteers ingested a single dose of placebo or 400 mg oral sulpiride, a dopamine D2-receptor antagonist, just before starting the recognition memory task in a randomized, double-blind, and placebo-controlled trial. The sulpiride group presented more false recognitions during visual and verbal processing than the placebo group, although both groups had the same indices of true memory. These findings demonstrate that dopamine D2 receptors blockade in healthy volunteers can specifically increase the rate of false recognitions. The findings fit well the two-process view of causes of false memories, the activation/monitoring failures model. PMID:27047394

Production of False Memories in Collaborative Memory Tasks Using the DRM Paradigm

ERIC Educational Resources Information Center

Saraiva, Magda; Albuquerque, Pedro B.; Arantes, Joana

2017-01-01

Studies on collaborative memory have revealed an interesting phenomenon called collaborative inhibition (CI) (i.e., nominal groups recall more information than collaborative groups). However, the results of studies on false memories in collaborative memory tasks are controversial. This study aimed to understand the production of false memories in…

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

PubMed

Tat, Michael J; Azuma, Tamiko

2016-01-01

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.

Experimental Effects of Acute Exercise on Prospective Memory and False Memory.

PubMed

Green, David; Loprinzi, Paul D

2018-01-01

Research demonstrates that acute exercise can enhance retrospective episodic memory performance. However, limited research has examined the effects of acute exercise on prospective memory, and no studies have examined the effects of exercise on false memory performance. This study examined the potential effects of acute exercise on prospective memory and false memory performance. A between-group randomized controlled trial was employed, with participants (college students; M age  = 20 years) randomized into an exercise group (15-minute acute bout of treadmill walking; N = 25) or a control group (15 minutes of sitting; N = 26). Prospective memory was assessed from two laboratory and two naturalistic assessments outside the lab. False memory was assessed using a word-list trial. There were no statistically significant differences in prospective memory based on group allocation (F Group×Time  = 1.17; P = 0.32; η 2  = 0.06). However, the control group recalled more false words and had a higher rate of false memory recognition (F Group×Time  = 3.15; P = 0.01; η 2  = 0.26). These findings indicate that acute moderate-intensity aerobic exercise is not associated with prospective memory performance but provides some suggestive evidence that acute exercise may reduce the rate of false memories.

Developmental Reversals in False Memory: Now You See Them, Now You Don't!

ERIC Educational Resources Information Center

Holliday, Robyn E.; Brainerd, Charles J.; Reyna, Valerie F.

2011-01-01

A developmental reversal in false memory is the counterintuitive phenomenon of higher levels of false memory in older children, adolescents, and adults than in younger children. The ability of verbatim memory to suppress this age trend in false memory was evaluated using the Deese-Roediger-McDermott (DRM) paradigm. Seven and 11-year-old children…

Phonological False Memories in Children and Adults: Evidence for a Developmental Reversal

ERIC Educational Resources Information Center

Swannell, Ellen R.; Dewhurst, Stephen A.

2012-01-01

False memories created by the Deese/Roediger-McDermott (DRM) procedure typically show a developmental reversal whereby levels of false recall increase with age. In contrast, false memories produced by phonological lists have been shown to decrease as age increases. In the current study we show that phonological false memories, like semantic false…

Semantic representations in the temporal pole predict false memories

PubMed Central

Chadwick, Martin J.; Anjum, Raeesa S.; Kumaran, Dharshan; Schacter, Daniel L.; Spiers, Hugo J.; Hassabis, Demis

2016-01-01

Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the “semantic hub” of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories. PMID:27551087

Semantic representations in the temporal pole predict false memories.

PubMed

Chadwick, Martin J; Anjum, Raeesa S; Kumaran, Dharshan; Schacter, Daniel L; Spiers, Hugo J; Hassabis, Demis

2016-09-06

Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the "semantic hub" of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories.

Get the gist? The effects of processing depth on false recognition in short-term and long-term memory.

PubMed

Flegal, Kristin E; Reuter-Lorenz, Patricia A

2014-07-01

Gist-based processing has been proposed to account for robust false memories in the converging-associates task. The deep-encoding processes known to enhance verbatim memory also strengthen gist memory and increase distortions of long-term memory (LTM). Recent research has demonstrated that compelling false memory illusions are relatively delay-invariant, also occurring under canonical short-term memory (STM) conditions. To investigate the contributions of gist to false memory at short and long delays, processing depth was manipulated as participants encoded lists of four semantically related words and were probed immediately, following a filled 3- to 4-s retention interval, or approximately 20 min later, in a surprise recognition test. In two experiments, the encoding manipulation dissociated STM and LTM on the frequency, but not the phenomenology, of false memory. Deep encoding at STM increases false recognition rates at LTM, but confidence ratings and remember/know judgments are similar across delays and do not differ as a function of processing depth. These results suggest that some shared and some unique processes underlie false memory illusions at short and long delays.

Motivated reconstruction: The effect of brand commitment on false memories.

PubMed

Montgomery, Nicole Votolato; Rajagopal, Priyali

2018-06-01

Across 5 studies, we examine the effect of prior brand commitment on the creation of false memories about product experience after reading online product reviews. We find that brand commitment and the valence of reviews to which consumers are exposed, interact to affect the incidence of false memories. Thus, highly committed consumers are more susceptible to the creation of false experience memories on exposure to positive versus negative reviews, whereas low commitment consumers exhibit similar levels of false memories in response to both positive and negative reviews. Further, these differences across brand commitment are attenuated when respondents are primed with an accuracy motivation, suggesting that the biasing effects of commitment are likely because of the motivation to defend the committed brand. Finally, we find that differences in false memories subsequently lead to differences in intentions to spread word-of-mouth (e.g., recommend the product to friends), suggesting that the consequences of false product experience memories can be significant for marketers and consumers. Our findings contribute to the literatures in false memory and marketing by documenting a motivated bias in false memories because of brand commitment. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Negative affect promotes encoding of and memory for details at the expense of the gist: affect, encoding, and false memories.

PubMed

Storbeck, Justin

2013-01-01

I investigated whether negative affective states enhance encoding of and memory for item-specific information reducing false memories. Positive, negative, and neutral moods were induced, and participants then completed a Deese-Roediger-McDermott (DRM) false-memory task. List items were presented in unique spatial locations or unique fonts to serve as measures for item-specific encoding. The negative mood conditions had more accurate memories for item-specific information, and they also had fewer false memories. The final experiment used a manipulation that drew attention to distinctive information, which aided learning for DRM words, but also promoted item-specific encoding. For the condition that promoted item-specific encoding, false memories were reduced for positive and neutral mood conditions to a rate similar to that of the negative mood condition. These experiments demonstrated that negative affective cues promote item-specific processing reducing false memories. People in positive and negative moods encode events differently creating different memories for the same event.

Individual differences in susceptibility to false memories: The effect of memory specificity.

PubMed

Dewhurst, Stephen A; Anderson, Rachel J; Berry, Donna M; Garner, Sarah R

2017-06-25

Previous research has highlighted the wide individual variability in susceptibility to the false memories produced by the Deese/Roediger-McDermott (DRM) procedure [Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58, 17-22; Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, & Cognition, 21, 803-814]. The current study investigated whether susceptibility to false memories is influenced by individual differences in the specificity of autobiographical memory retrieval. Memory specificity was measured using the Sentence Completion for Events from the Past Test (SCEPT) [Raes, F., Hermans, D., Williams, J. M. G., & Eelen, P. (2007). A sentence completion procedure as an alternative to the Autobiographical Memory Test for assessing overgeneral memory in non-clinical populations. Memory, 15, 495-507]. Memory specificity did not correlate with correct recognition, but a specific retrieval style was positively correlated with levels of false recognition. It is proposed that the contextual details that frequently accompany false memories of nonstudied lures are more accessible in individuals with specific retrieval styles.

Compelling Untruths: Content Borrowing and Vivid False Memories

ERIC Educational Resources Information Center

Lampinen, James Michael; Meier, Christopher R.; Arnal, Jack D.; Leding, Juliana K.

2005-01-01

False memories are sometimes accompanied by surprisingly vivid experiential detail that makes them difficult to distinguish from actual memories. Such strikingly real false memories may be produced by a process called content borrowing in which details from presented items are errantly borrowed to corroborate the occurrence of the false memory…

The Deese-Roediger-McDermott (DRM) Task: A Simple Cognitive Paradigm to Investigate False Memories in the Laboratory.

PubMed

Pardilla-Delgado, Enmanuelle; Payne, Jessica D

2017-01-31

The Deese, Roediger and McDermott (DRM) task is a false memory paradigm in which subjects are presented with lists of semantically related words (e.g., nurse, hospital, etc.) at encoding. After a delay, subjects are asked to recall or recognize these words. In the recognition memory version of the task, subjects are asked whether they remember previously presented words, as well as related (but never presented) critical lure words ('doctor'). Typically, the critical word is recognized with high probability and confidence. This false memory effect has been robustly demonstrated across short (e.g., immediate, 20 min) and long (e.g., 1, 7, 60 d) delays between encoding and memory testing. A strength of using this task to study false memory is its simplicity and short duration. If encoding and retrieval components of the task occur in the same session, the entire task can take as little as 2 - 30 min. However, although the DRM task is widely considered a 'false memory' paradigm, some researchers consider DRM illusions to be based on the activation of semantic memory networks in the brain, and argue that such semantic gist-based false memory errors may actually be useful in some scenarios (e.g., remembering the forest for the trees; remembering that a word list was about "doctors", even though the actual word "doctor" was never presented for study). Remembering the gist of experience (instead of or along with individual details) is arguably an adaptive process and this task has provided a great deal of knowledge about the constructive, adaptive nature of memory. Therefore, researchers should use caution when discussing the overall reach and implications of their experiments when using this task to study 'false memory', as DRM memory errors may not adequately reflect false memories in the real world, such as false memory in eyewitness testimony, or false memories of sexual abuse.

False memory for context activates the parahippocampal cortex.

PubMed

Karanian, Jessica M; Slotnick, Scott D

2014-01-01

Previous studies have reported greater activity in the parahippocampal cortex during true memory than false memory, which has been interpreted as reflecting greater sensory processing during true memory. However, in these studies, sensory detail and contextual information were confounded. In the present fMRI study, we employed a novel paradigm to dissociate these factors. During encoding, abstract shapes were presented in one of two contexts (i.e., moving or stationary). During retrieval, participants classified shapes as previously "moving" or "stationary." Critically, contextual processing was relatively greater during false memory ("moving" responses to stationary items), while sensory processing was relatively greater during true memory ("moving" responses to moving items). Within the medial temporal lobe, false memory versus true memory produced greater activity in the parahippocampal cortex, whereas true memory versus false memory produced greater activity in the hippocampus. The present results indicate that the parahippocampal cortex mediates contextual processing rather than sensory processing.

Effects of aging and education on false memory.

PubMed

Lee, Yuh-Shiow; Lee, Chia-Lin; Yang, Hua-Te

2012-01-01

This study examined the effects of aging and education on participants' false memory for words that were not presented. Three age groups of participants with either a high or low education level were asked to study lists of semantically related words. Both age and education were found to affect veridical and false memory, as indicated in the recall and recognition of the studied word and nonstudied lures. A low education level had a negative effect on memory performance for both young and middle-aged adults. Older adults with a high level of education had a higher level of false memory than those with a lower education level. The results of this study are discussed in terms of the importance of education on false memory and mechanisms that create false memory of words in older adults.

Reduced False Memory after Sleep

ERIC Educational Resources Information Center

Fenn, Kimberly M.; Gallo, David A.; Margoliash, Daniel; Roediger, Henry L., III; Nusbaum, Howard C.

2009-01-01

Several studies have shown that sleep contributes to the successful maintenance of previously encoded information. This research has focused exclusively on memory for studied events, as opposed to false memories. Here we report three experiments showing that sleep reduces false memories in the Deese-Roediger-McDermott (DRM) memory illusion. False…

False memories in highly superior autobiographical memory individuals

PubMed Central

Patihis, Lawrence; Frenda, Steven J.; LePort, Aurora K. R.; Petersen, Nicole; Nichols, Rebecca M.; Stark, Craig E. L.; McGaugh, James L.; Loftus, Elizabeth F.

2013-01-01

The recent identification of highly superior autobiographical memory (HSAM) raised the possibility that there may be individuals who are immune to memory distortions. We measured HSAM participants’ and age- and sex-matched controls’ susceptibility to false memories using several research paradigms. HSAM participants and controls were both susceptible to false recognition of nonpresented critical lure words in an associative word-list task. In a misinformation task, HSAM participants showed higher overall false memory compared with that of controls for details in a photographic slideshow. HSAM participants were equally as likely as controls to mistakenly report they had seen nonexistent footage of a plane crash. Finding false memories in a superior-memory group suggests that malleable reconstructive mechanisms may be fundamental to episodic remembering. Paradoxically, HSAM individuals may retrieve abundant and accurate autobiographical memories using fallible reconstructive processes. PMID:24248358

Hippocampal size is related to short-term true and false memory, and right fusiform size is related to long-term true and false memory.

PubMed

Zhu, Bi; Chen, Chuansheng; Loftus, Elizabeth F; He, Qinghua; Lei, Xuemei; Dong, Qi; Lin, Chongde

2016-11-01

There is a keen interest in identifying specific brain regions that are related to individual differences in true and false memories. Previous functional neuroimaging studies showed that activities in the hippocampus, right fusiform gyrus, and parahippocampal gyrus were associated with true and false memories, but no study thus far has examined whether the structures of these brain regions are associated with short-term and long-term true and false memories. To address that question, the current study analyzed data from 205 healthy young adults, who had valid data from both structural brain imaging and a misinformation task. In the misinformation task, subjects saw the crime scenarios, received misinformation, and took memory tests about the crimes an hour later and again after 1.5 years. Results showed that bilateral hippocampal volume was associated with short-term true and false memories, whereas right fusiform gyrus volume and surface area were associated with long-term true and false memories. This study provides the first evidence for the structural neural bases of individual differences in short-term and long-term true and false memories.

False Memories in Children and Adults: Age, Distinctiveness, and Subjective Experience.

ERIC Educational Resources Information Center

Ghetti, Simona; Qin, Jianjian; Goodman, Gail S.

2002-01-01

Investigated developmental trends associated with the Deese/Roediger-McDermott false-memory effect, the role of distinctive information, and subjective experience of true/false memories. Found that 5-year-olds recalled more false memories than adults but no age differences in recognition of critical lures. Distinctive information reduced false…

Young children have difficulty ascribing true beliefs.

PubMed

Riggs, Kevin J; Simpson, Andrew

2005-05-01

Using the format of a false belief task (Wimmer & Perner, 1983), we investigated the ability of 88 3- and 4-year-olds to ascribe a previously held true belief to a story protagonist. In an unexpected transfer task, children found true belief ascription as difficult as false belief ascription even though they could answer memory questions about story details. Results are discussed in relation to theoretical accounts of theory of mind development that stress the importance of understanding the falsity of belief, and those accounts that stress the importance of information or executive processes.

Theory of mind and executive function: working-memory capacity and inhibitory control as predictors of false-belief task performance.

PubMed

Mutter, Brigitte; Alcorn, Mark B; Welsh, Marilyn

2006-06-01

This study of the relationship between theory of mind and executive function examined whether on the false-belief task age differences between 3 and 5 ears of age are related to development of working-memory capacity and inhibitory processes. 72 children completed tasks measuring false belief, working memory, and inhibition. Significant age effects were observed for false-belief and working-memory performance, as well as for the false-alarm and perseveration measures of inhibition. A simultaneous multiple linear regression specified the contribution of age, inhibition, and working memory to the prediction of false-belief performance. This model was significant, explaining a total of 36% of the variance. To examine the independent contributions of the working-memory and inhibition variables, after controlling for age, two hierarchical multiple linear regressions were conducted. These multiple regression analyses indicate that working memory and inhibition make small, overlapping contributions to false-belief performance after accounting for age, but that working memory, as measured in this study, is a somewhat better predictor of false-belief understanding than is inhibition.

The effects of sleep restriction and sleep deprivation in producing false memories.

PubMed

Chatburn, Alex; Kohler, Mark J; Payne, Jessica D; Drummond, Sean P A

2017-01-01

False memory has been claimed to be the result of an associative process of generalisation, as well as to be representative of memory errors. These can occur at any stage of memory encoding, consolidation, or retrieval, albeit through varied mechanisms. The aim of this paper is to experimentally determine: (i) if cognitive dysfunction brought about by sleep loss at the time of stimulus encoding can influence false memory production; and (ii) whether this relationship holds across sensory modalities. Subjects undertook both the Deese-Roedigger-McDermott (DRM) false memory task and a visual task designed to produce false memories. Performance was measured while subjects were well-rested (9h Time in Bed or TIB), and then again when subjects were either sleep restricted (4h TIB for 4 nights) or sleep deprived (30h total SD). Results indicate (1) that partial and total sleep loss produced equivalent effects in terms of false and veridical verbal memory, (2) that subjects performed worse after sleep loss (regardless of whether this was partial or total sleep loss) on cued recognition-based false and veridical verbal memory tasks, and that sleep loss interfered with subjects' ability to recall veridical, but not false memories under free recall conditions, and (3) that there were no effects of sleep loss on a visual false memory task. This is argued to represent the dysfunction and slow repair of an online verbal associative process in the brain following inadequate sleep. Copyright © 2016 Elsevier Inc. All rights reserved.

True and False DRM Memories: Differences Detected with an Implicit Task

PubMed Central

Marini, Maddalena; Agosta, Sara; Mazzoni, Giuliana; Barba, Gianfranco Dalla; Sartori, Giuseppe

2012-01-01

Memory is prone to illusions. When people are presented with lists of words associated with a non-presented critical lure, they produce a high level of false recognitions (false memories) for non-presented related stimuli indistinguishable, at the explicit level, from presented words (DRM paradigm). We assessed whether true and false DRM memories can be distinguished at the implicit level by using the autobiographical IAT (aIAT), a novel method based on indirect measures that permits to detect true autobiographical events encoded in the respondent’s mind/brain. In our experiment, after a DRM task participants performed two aIATs: the first aimed at testing implicit memory for presented words (true-memories aIAT) and the second aimed at evaluating implicit memory for critical lures (false-memories aIAT). Specifically, the two aIATs assessed the association of presented words and critical lures with the logical dimension “true.” Results showed that the aIAT detected a greater association of presented words than critical lures with the logical dimension “true.” This result indicates that although true and false DRM memories are indistinguishable at the explicit level a different association of the true and false DRM memories with the logical dimension “true” can be detected at the implicit level, and suggests that the aIAT may be a sensitive instrument to detect differences between true and false DRM memories. PMID:22969740

Over-Distribution in Source Memory

PubMed Central

Brainerd, C. J.; Reyna, V. F.; Holliday, R. E.; Nakamura, K.

2012-01-01

Semantic false memories are confounded with a second type of error, over-distribution, in which items are attributed to contradictory episodic states. Over-distribution errors have proved to be more common than false memories when the two are disentangled. We investigated whether over-distribution is prevalent in another classic false memory paradigm: source monitoring. It is. Conventional false memory responses (source misattributions) were predominantly over-distribution errors, but unlike semantic false memory, over-distribution also accounted for more than half of true memory responses (correct source attributions). Experimental control of over-distribution was achieved via a series of manipulations that affected either recollection of contextual details or item memory (concreteness, frequency, list-order, number of presentation contexts, and individual differences in verbatim memory). A theoretical model was used to analyze the data (conjoint process dissociation) that predicts that predicts that (a) over-distribution is directly proportional to item memory but inversely proportional to recollection and (b) item memory is not a necessary precondition for recollection of contextual details. The results were consistent with both predictions. PMID:21942494

Eliminating Age Differences in Children's and Adults' Suggestibility and Memory Conformity Effects

ERIC Educational Resources Information Center

Otgaar, Henry; Howe, Mark L.; Brackmann, Nathalie; van Helvoort, Daniël H. J.

2017-01-01

We examined whether typical developmental trends in suggestion-induced false memories (i.e., age-related decrease) could be changed. Using theoretical principles from the spontaneous false memory field, we adapted 2 often-used false memory procedures: misinformation (Experiment 1) and memory conformity (Experiment 2). In Experiment 1, 7- to…

Undermining belief in false memories leads to less efficient problem-solving behaviour.

PubMed

Wang, Jianqin; Otgaar, Henry; Howe, Mark L; Smeets, Tom; Merckelbach, Harald; Nahouli, Zacharia

2017-08-01

Memories of events for which the belief in the occurrence of those events is undermined, but recollection is retained, are called nonbelieved memories (NBMs). The present experiments examined the effects of NBMs on subsequent problem-solving behaviour. In Experiment 1, we challenged participants' beliefs in their memories and examined whether NBMs affected subsequent solution rates on insight-based problems. True and false memories were elicited using the Deese/Roediger-McDermott (DRM) paradigm. Then participants' belief in true and false memories was challenged by telling them the item had not been presented. We found that when the challenge led to undermining belief in false memories, fewer problems were solved than when belief was not challenged. In Experiment 2, a similar procedure was used except that some participants solved the problems one week rather than immediately after the feedback. Again, our results showed that undermining belief in false memories resulted in lower problem solution rates. These findings suggest that for false memories, belief is an important agent in whether memories serve as effective primes for immediate and delayed problem-solving.

Neural events that underlie remembering something that never happened.

PubMed

Gonsalves, B; Paller, K A

2000-12-01

We induced people to experience a false-memory illusion by first asking them to visualize common objects when cued with the corresponding word; on some trials, a photograph of the object was presented 1800 ms after the cue word. We then tested their memory for the photographs. Posterior brain potentials in response to words at encoding were more positive if the corresponding object was later falsely remembered as a photograph. Similar brain potentials during the memory test were more positive for true than for false memories. These results implicate visual imagery in the generation of false memories and provide neural correlates of processing differences between true and false memories.

Factors that influence the generation of autobiographical memory conjunction errors

PubMed Central

Devitt, Aleea L.; Monk-Fromont, Edwin; Schacter, Daniel L.; Addis, Donna Rose

2015-01-01

The constructive nature of memory is generally adaptive, allowing us to efficiently store, process and learn from life events, and simulate future scenarios to prepare ourselves for what may come. However, the cost of a flexibly constructive memory system is the occasional conjunction error, whereby the components of an event are authentic, but the combination of those components is false. Using a novel recombination paradigm, it was demonstrated that details from one autobiographical memory may be incorrectly incorporated into another, forming autobiographical memory conjunction errors that elude typical reality monitoring checks. The factors that contribute to the creation of these conjunction errors were examined across two experiments. Conjunction errors were more likely to occur when the corresponding details were partially rather than fully recombined, likely due to increased plausibility and ease of simulation of partially recombined scenarios. Brief periods of imagination increased conjunction error rates, in line with the imagination inflation effect. Subjective ratings suggest that this inflation is due to similarity of phenomenological experience between conjunction and authentic memories, consistent with a source monitoring perspective. Moreover, objective scoring of memory content indicates that increased perceptual detail may be particularly important for the formation of autobiographical memory conjunction errors. PMID:25611492

Comparison of neural activity that leads to true memories, false memories, and forgetting: An fMRI study of the misinformation effect.

PubMed

Baym, Carol L; Gonsalves, Brian D

2010-09-01

False memories can occur when people are exposed to misinformation about a past event. Of interest here are the neural mechanisms of this type of memory failure. In the present study, participants viewed photographic vignettes of common activities during an original event phase (OEP), while we monitored their brain activity using fMRI. Later, in a misinformation phase, participants viewed sentences describing the studied photographs, some of which contained information conflicting with that depicted in the photographs. One day later, participants returned for a surprise item memory recognition test for the content of the photographs. Results showed reliable creation of false memories, in that participants reported information that had been presented in the verbal misinformation but not in the photographs. Several regions were more active during the OEP for later accurate memory than for forgetting, but they were also more active for later false memories, indicating that false memories in this paradigm are not simply caused by failure to encode the original event. There was greater activation in the ventral visual stream for subsequent true memories than for subsequent false memories, however, suggesting that differences in encoding may contribute to later susceptibility to misinformation.

Semantic Congruence Accelerates the Onset of the Neural Signals of Successful Memory Encoding.

PubMed

Packard, Pau A; Rodríguez-Fornells, Antoni; Bunzeck, Nico; Nicolás, Berta; de Diego-Balaguer, Ruth; Fuentemilla, Lluís

2017-01-11

As the stream of experience unfolds, our memory system rapidly transforms current inputs into long-lasting meaningful memories. A putative neural mechanism that strongly influences how input elements are transformed into meaningful memory codes relies on the ability to integrate them with existing structures of knowledge or schemas. However, it is not yet clear whether schema-related integration neural mechanisms occur during online encoding. In the current investigation, we examined the encoding-dependent nature of this phenomenon in humans. We showed that actively integrating words with congruent semantic information provided by a category cue enhances memory for words and increases false recall. The memory effect of such active integration with congruent information was robust, even with an interference task occurring right after each encoding word list. In addition, via electroencephalography, we show in 2 separate studies that the onset of the neural signals of successful encoding appeared early (∼400 ms) during the encoding of congruent words. That the neural signals of successful encoding of congruent and incongruent information followed similarly ∼200 ms later suggests that this earlier neural response contributed to memory formation. We propose that the encoding of events that are congruent with readily available contextual semantics can trigger an accelerated onset of the neural mechanisms, supporting the integration of semantic information with the event input. This faster onset would result in a long-lasting and meaningful memory trace for the event but, at the same time, make it difficult to distinguish it from plausible but never encoded events (i.e., related false memories). Conceptual or schema congruence has a strong influence on long-term memory. However, the question of whether schema-related integration neural mechanisms occur during online encoding has yet to be clarified. We investigated the neural mechanisms reflecting how the active integration of words with congruent semantic categories enhances memory for words and increases false recall of semantically related words. We analyzed event-related potentials during encoding and showed that the onset of the neural signals of successful encoding appeared early (∼400 ms) during the encoding of congruent words. Our findings indicate that congruent events can trigger an accelerated onset of neural encoding mechanisms supporting the integration of semantic information with the event input. Copyright © 2017 the authors 0270-6474/17/370291-11$15.00/0.

Arousal-But Not Valence-Reduces False Memories at Retrieval.

PubMed

Mirandola, Chiara; Toffalini, Enrico

2016-01-01

Mood affects both memory accuracy and memory distortions. However, some aspects of this relation are still poorly understood: (1) whether valence and arousal equally affect false memory production, and (2) whether retrieval-related processes matter; the extant literature typically shows that mood influences memory performance when it is induced before encoding, leaving unsolved whether mood induced before retrieval also impacts memory. We examined how negative, positive, and neutral mood induced before retrieval affected inferential false memories and related subjective memory experiences. A recognition-memory paradigm for photographs depicting script-like events was employed. Results showed that individuals in both negative and positive moods-similar in arousal levels-correctly recognized more target events and endorsed fewer false memories (and these errors were linked to remember responses less frequently), compared to individuals in neutral mood. This suggests that arousal (but not valence) predicted memory performance; furthermore, we found that arousal ratings provided by participants were more adequate predictors of memory performance than their actual belonging to either positive, negative or neutral mood groups. These findings suggest that arousal has a primary role in affecting memory, and that mood exerts its power on true and false memory even when induced at retrieval.

Arousal—But Not Valence—Reduces False Memories at Retrieval

PubMed Central

Mirandola, Chiara; Toffalini, Enrico

2016-01-01

Mood affects both memory accuracy and memory distortions. However, some aspects of this relation are still poorly understood: (1) whether valence and arousal equally affect false memory production, and (2) whether retrieval-related processes matter; the extant literature typically shows that mood influences memory performance when it is induced before encoding, leaving unsolved whether mood induced before retrieval also impacts memory. We examined how negative, positive, and neutral mood induced before retrieval affected inferential false memories and related subjective memory experiences. A recognition-memory paradigm for photographs depicting script-like events was employed. Results showed that individuals in both negative and positive moods–similar in arousal levels–correctly recognized more target events and endorsed fewer false memories (and these errors were linked to remember responses less frequently), compared to individuals in neutral mood. This suggests that arousal (but not valence) predicted memory performance; furthermore, we found that arousal ratings provided by participants were more adequate predictors of memory performance than their actual belonging to either positive, negative or neutral mood groups. These findings suggest that arousal has a primary role in affecting memory, and that mood exerts its power on true and false memory even when induced at retrieval. PMID:26938737

The development of neural correlates for memory formation

PubMed Central

Ofen, Noa

2012-01-01

A growing body of literature considers the development of episodic memory systems in the brain; the majority are neuroimaging studies conducted during memory encoding in order to explore developmental trajectories in memory formation. This review considers evidence from behavioral studies of memory development, neural correlates of memory formation in adults, and structural brain development, all of which form the foundation of a developmental cognitive neuroscience approach to memory development. I then aim to integrate the current evidence from developmental functional neuroimaging studies of memory formation with respect to three hypotheses. First, memory development reflects the development in the use of memory strategies, linked to prefrontal cortex. Second, developmental effects within the medial temporal lobes are more complex, and correspond to current notions about the nature in which the MTL support the formation of memory. Third, neurocognitive changes in content representation influence memory. Open issues and current directions are discussed. PMID:22414608

The effect of articulatory suppression on implicit and explicit false memory in the DRM paradigm.

PubMed

Van Damme, Ilse; Menten, Jan; d'Ydewalle, Gery

2010-11-01

Several studies have shown that reliable implicit false memory can be obtained in the DRM paradigm. There has been considerable debate, however, about whether or not conscious activation of critical lures during study is a necessary condition for this. Recent findings have revealed that articulatory suppression prevents subsequent false priming in an anagram task (Lovden & Johansson, 2003). The present experiment sought to replicate and extend these findings to an implicit word stem completion task, and to additionally investigate the effect of articulatory suppression on explicit false memory. Results showed an inhibitory effect of articulatory suppression on veridical memory, as well as on implicit false memory, whereas the level of explicit false memory was heightened. This suggests that articulatory suppression did not merely eliminate conscious lure activation, but had a more general capacity-delimiting effect. The drop in veridical memory can be attributed to diminished encoding of item-specific information. Superficial encoding also limited the spreading of semantic activation during study, which inhibited later false priming. In addition, the lack of item-specific and phenomenological details caused impaired source monitoring at test, resulting in heightened explicit false memory.

Emotional content enhances true but not false memory for categorized stimuli.

PubMed

Choi, Hae-Yoon; Kensinger, Elizabeth A; Rajaram, Suparna

2013-04-01

Past research has shown that emotion enhances true memory, but that emotion can either increase or decrease false memory. Two theoretical possibilities-the distinctiveness of emotional stimuli and the conceptual relatedness of emotional content-have been implicated as being responsible for influencing both true and false memory for emotional content. In the present study, we sought to identify the mechanisms that underlie these mixed findings by equating the thematic relatedness of the study materials across each type of valence used (negative, positive, or neutral). In three experiments, categorically bound stimuli (e.g., funeral, pets, and office items) were used for this purpose. When the encoding task required the processing of thematic relatedness, a significant true-memory enhancement for emotional content emerged in recognition memory, but no emotional boost to false memory (exp. 1). This pattern persisted for true memory with a longer retention interval between study and test (24 h), and false recognition was reduced for emotional items (exp. 2). Finally, better recognition memory for emotional items once again emerged when the encoding task (arousal ratings) required the processing of the emotional aspect of the study items, with no emotional boost to false recognition (EXP. 3). Together, these findings suggest that when emotional and neutral stimuli are equivalently high in thematic relatedness, emotion continues to improve true memory, but it does not override other types of grouping to increase false memory.

Differentiating true and false schematic memories in older adults.

PubMed

Webb, Christina E; Dennis, Nancy A

2018-02-06

While schemas aid memory for schematically related information, the gist induced by the schema can also lead to high rates of false memories, especially in older adults. The neural mechanisms that support and differentiate true and false memories in aging are not well understood. The current study sought to clarify this, using a novel scene paradigm to investigate the role of schemas on true and false memories in older adults. Healthy older adults encoded schematic scenes (e.g., bathroom). At retrieval, participants were tested on their memory for both schematic and non-schematic targets and lures while fMRI data was collected. Results indicate that true memories were supported by the typical retrieval network, and activity in this network was greater for true than false memories. Schema specific retrieval was supported by mPFC, extending this common finding to aging. While no region differentiated false memories compared to correct rejections, results showed that individual differences in false memory rates were associated with variability in neural activity. The findings underscore the importance of elucidating the neural basis of cognition within older adults, as well as the specific contribution of individual differences to the neural basis of memory errors in aging. © The Author(s) 2018. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Developmental reversals in false memory: Effects of emotional valence and arousal.

PubMed

Brainerd, C J; Holliday, R E; Reyna, V F; Yang, Y; Toglia, M P

2010-10-01

Do the emotional valence and arousal of events distort children's memories? Do valence and arousal modulate counterintuitive age increases in false memory? We investigated those questions in children, adolescents, and adults using the Cornell/Cortland Emotion Lists, a word list pool that induces false memories and in which valence and arousal can be manipulated factorially. False memories increased with age for unpresented semantic associates of word lists, and net accuracy (the ratio of true memory to total memory) decreased with age. These surprising developmental trends were more pronounced for negatively valenced materials than for positively valenced materials, they were more pronounced for high-arousal materials than for low-arousal materials, and developmental increases in the effects of arousal were small in comparison with developmental increases in the effects of valence. These findings have ramifications for legal applications of false memory research; materials that share the emotional hallmark of crimes (events that are negatively valenced and arousing) produced the largest age increases in false memory and the largest age declines in net accuracy. Copyright 2010 Elsevier Inc. All rights reserved.

False memories, but not false beliefs, affect implicit attitudes for food preferences.

PubMed

Howe, David; Anderson, Rachel J; Dewhurst, Stephen A

2017-09-01

Previous studies have found that false memories and false beliefs of childhood experiences can have attitudinal consequences. Previous studies have, however, focused exclusively on explicit attitude measures without exploring whether implicit attitudes are similarly affected. Using a false feedback/imagination inflation paradigm, false memories and beliefs of enjoying a certain food as a child were elicited in participants, and their effects were assessed using both explicit attitude measures (self-report questionnaires) and implicit measures (a Single-Target Implicit Association Test). Positive changes in explicit attitudes were observed both in participants with false memories and participants with false beliefs. In contrast, only participants with false memories exhibited more positive implicit attitudes. The findings are discussed in terms of theories of explicit and implicit attitudes. Copyright © 2017 Elsevier B.V. All rights reserved.

Can false memories be created through nonconscious processes?

PubMed

Zeelenberg, René; Plomp, Gijs; Raaijmakers, Jeroen G W

2003-09-01

Presentation times of study words presented in the Deese/Roediger and McDermott (DRM) paradigm varied from 20 to 2000 ms per word in an attempt to replicate the false memory effect following extremely short presentations reported by. Both in a within-subjects design (Experiment 1) and in a between-subjects design (Experiment 2) subjects showed memory for studied words as well as a false memory effect for related critical lures in the 2000-ms condition. However, in the conditions with shorter presentation times (20 ms in Experiment 1; 20 and 40 ms in Experiment 2) no memory for studied words, nor a false memory effect was found. We argue that there is at present no strong evidence supporting the claim for a nonconscious basis of the false memory effect.

False memory for face in short-term memory and neural activity in human amygdala.

PubMed

Iidaka, Tetsuya; Harada, Tokiko; Sadato, Norihiro

2014-12-03

Human memory is often inaccurate. Similar to words and figures, new faces are often recognized as seen or studied items in long- and short-term memory tests; however, the neural mechanisms underlying this false memory remain elusive. In a previous fMRI study using morphed faces and a standard false memory paradigm, we found that there was a U-shaped response curve of the amygdala to old, new, and lure items. This indicates that the amygdala is more active in response to items that are salient (hit and correct rejection) compared to items that are less salient (false alarm), in terms of memory retrieval. In the present fMRI study, we determined whether the false memory for faces occurs within the short-term memory range (a few seconds), and assessed which neural correlates are involved in veridical and illusory memories. Nineteen healthy participants were scanned by 3T MRI during a short-term memory task using morphed faces. The behavioral results indicated that the occurrence of false memories was within the short-term range. We found that the amygdala displayed a U-shaped response curve to memory items, similar to those observed in our previous study. These results suggest that the amygdala plays a common role in both long- and short-term false memory for faces. We made the following conclusions: First, the amygdala is involved in detecting the saliency of items, in addition to fear, and supports goal-oriented behavior by modulating memory. Second, amygdala activity and response time might be related with a subject's response criterion for similar faces. Copyright © 2014 Elsevier B.V. All rights reserved.

Disturbance of time orientation, attention, and verbal memory in amnesic patients with confabulation.

PubMed

Shingaki, Honoka; Park, Paeksoon; Ueda, Keita; Murai, Toshiya; Tsukiura, Takashi

2016-01-01

Confabulation is often observed in amnesic patients after brain damage. However, evidence regarding the relationship between confabulation and other neuropsychological functions is scarce. In addition, previous studies have proposed two possibilities of the relationship between confabulation and false memory, in which patients with confabulation are likely to retrieve false memories, or confabulations are relatively independent of false memories. The present study investigated how confabulation is related to various cognitive functions, including orientation, attention, frontal lobe function, memory, and mental status, and to false memories, as assessed by the Deese-Roediger-Mcdermott (DRM) paradigm. Patients with organic amnesia participated, and confabulations were evaluated using the Confabulation Battery. Amnestic patients were classified into two groups: confabulating (CP) and nonconfabulating patients (NCP). The CP group was significantly impaired in time orientation, attention, and verbal memory, compared to the NCP group and age-matched healthy controls (HC). Results of the DRM paradigm revealed no significant difference in false memory retrieval induced by critical lures across CP, NCP, and HC groups. Confabulating responses in organic amnesia could be in part induced by disturbance of time consciousness and attention control in severe impairment of verbal memories, and confabulation and false memory could be modulated by different cognitive systems.

The Distinctions of False and Fuzzy Memories.

ERIC Educational Resources Information Center

Schooler, Jonathan W.

1998-01-01

Notes that fuzzy-trace theory has been used to understand false memories of children. Demonstrates the irony imbedded in the theory, maintaining that a central implication of fuzzy-trace theory is that some errors characterized as false memories are not really false at all. These errors, when applied to false alarms to related lures, are best…

High estradiol levels improve false memory rates and meta-memory in highly schizotypal women.

PubMed

Hodgetts, Sophie; Hausmann, Markus; Weis, Susanne

2015-10-30

Overconfidence in false memories is often found in patients with schizophrenia and healthy participants with high levels of schizotypy, indicating an impairment of meta-cognition within the memory domain. In general, cognitive control is suggested to be modulated by natural fluctuations in oestrogen. However, whether oestrogen exerts beneficial effects on meta-memory has not yet been investigated. The present study sought to provide evidence that high levels of schizotypy are associated with increased false memory rates and overconfidence in false memories, and that these processes may be modulated by natural differences in estradiol levels. Using the Deese-Roediger-McDermott paradigm, it was found that highly schizotypal participants with high estradiol produced significantly fewer false memories than those with low estradiol. No such difference was found within the low schizotypy participants. Highly schizotypal participants with high estradiol were also less confident in their false memories than those with low estradiol; low schizotypy participants with high estradiol were more confident. However, these differences only approached significance. These findings suggest that the beneficial effect of estradiol on memory and meta-memory observed in healthy participants is specific to highly schizotypal individuals and might be related to individual differences in baseline dopaminergic activity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Can False Memories Prime Problem Solutions?

ERIC Educational Resources Information Center

Howe, Mark L.; Garner, Sarah R.; Dewhurst, Stephen A.; Ball, Linden J.

2010-01-01

Previous research has suggested that false memories can prime performance on related implicit and explicit memory tasks. The present research examined whether false memories can also be used to prime higher order cognitive processes, namely, insight-based problem solving. Participants were asked to solve a number of compound remote associate task…

"Disorganized in time": impact of bottom-up and top-down negative emotion generation on memory formation among healthy and traumatized adolescents.

PubMed

Guillery-Girard, Bérengère; Clochon, Patrice; Giffard, Bénédicte; Viard, Armelle; Egler, Pierre-Jean; Baleyte, Jean-Marc; Eustache, Francis; Dayan, Jacques

2013-09-01

"Travelling in time," a central feature of episodic memory is severely affected among individuals with Post Traumatic Stress Disorder (PTSD) with two opposite effects: vivid traumatic memories are unorganized in temporality (bottom-up processes), non-traumatic personal memories tend to lack spatio-temporal details and false recognitions occur more frequently that in the general population (top-down processes). To test the effect of these two types of processes (i.e. bottom-up and top-down) on emotional memory, we conducted two studies in healthy and traumatized adolescents, a period of life in which vulnerability to emotion is particularly high. Using negative and neutral images selected from the international affective picture system (IAPS), stimuli were divided into perceptual images (emotion generated by perceptual details) and conceptual images (emotion generated by the general meaning of the material). Both categories of stimuli were then used, along with neutral pictures, in a memory task with two phases (encoding and recognition). In both populations, we reported a differential effect of the emotional material on encoding and recognition. Negative perceptual scenes induced an attentional capture effect during encoding and enhanced the recollective distinctiveness. Conversely, the encoding of conceptual scenes was similar to neutral ones, but the conceptual relatedness induced false memories at retrieval. However, among individuals with PTSD, two subgroups of patients were identified. The first subgroup processed the scenes faster than controls, except for the perceptual scenes, and obtained similar performances to controls in the recognition task. The second subgroup group desmonstrated an attentional deficit in the encoding task with no benefit from the distinctiveness associated with negative perceptual scenes on memory performances. These findings provide a new perspective on how negative emotional information may have opposite influences on memory in normal and traumatized individuals. It also gives clues to understand how intrusive memories and overgeneralization takes place in PTSD. Copyright © 2013 Elsevier Ltd. All rights reserved.

Confident false memories for spatial location are mediated by V1.

PubMed

Karanian, Jessica M; Slotnick, Scott D

2018-06-27

Prior functional magnetic resonance imaging (fMRI) results suggest that true memories, but not false memories, activate early sensory cortex. It is thought that false memories, which reflect conscious processing, do not activate early sensory cortex because these regions are associated with nonconscious processing. We posited that false memories may activate the earliest visual cortical processing region (i.e., V1) when task conditions are manipulated to evoke conscious processing in this region. In an fMRI experiment, abstract shapes were presented to the left or right of fixation during encoding. During retrieval, old shapes were presented at fixation and participants characterized each shape as previously on the "left" or "right" followed by an "unsure"-"sure"-"very sure" confidence rating. False memories for spatial location (i.e., "right"/left or "left"/right trials with "sure" or "very sure" confidence ratings) were associated with activity in bilateral early visual regions, including V1. In a follow-up fMRI-guided transcranial magnetic stimulation (TMS) experiment that employed the same paradigm, we assessed whether V1 activity was necessary for false memory construction. Between the encoding phase and the retrieval phase of each run, TMS (1 Hz, 8 min) was used to target the location of false memory activity (identified in the fMRI experiment) in left V1, right V1, or the vertex (control site). Confident false memories for spatial location were significantly reduced following TMS to V1, as compared to vertex. The results of the present experiments provide convergent evidence that early sensory cortex can contribute to false memory construction under particular task conditions.

False memories to emotional stimuli are not equally affected in right- and left-brain-damaged stroke patients.

PubMed

Buratto, Luciano Grüdtner; Zimmermann, Nicolle; Ferré, Perrine; Joanette, Yves; Fonseca, Rochele Paz; Stein, Lilian Milnitsky

2014-10-01

Previous research has attributed to the right hemisphere (RH) a key role in eliciting false memories to visual emotional stimuli. These results have been explained in terms of two right-hemisphere properties: (i) that emotional stimuli are preferentially processed in the RH and (ii) that visual stimuli are represented more coarsely in the RH. According to this account, false emotional memories are preferentially produced in the RH because emotional stimuli are both more strongly and more diffusely activated during encoding, leaving a memory trace that can be erroneously reactivated by similar but unstudied emotional items at test. If this right-hemisphere hypothesis is correct, then RH damage should result in a reduction in false memories to emotional stimuli relative to left-hemisphere lesions. To investigate this possibility, groups of right-brain-damaged (RBD, N=15), left-brain-damaged (LBD, N=15) and healthy (HC, N=30) participants took part in a recognition memory experiment with emotional (negative and positive) and non-emotional pictures. False memories were operationalized as incorrect responses to unstudied pictures that were similar to studied ones. Both RBD and LBD participants showed similar reductions in false memories for negative pictures relative to controls. For positive pictures, however, false memories were reduced only in RBD patients. The results provide only partial support for the right-hemisphere hypothesis and suggest that inter-hemispheric cooperation models may be necessary to fully account for false emotional memories. Copyright © 2014 Elsevier Inc. All rights reserved.

False memories and memory confidence in borderline patients.

PubMed

Schilling, Lisa; Wingenfeld, Katja; Spitzer, Carsten; Nagel, Matthias; Moritz, Steffen

2013-12-01

Mixed results have been obtained regarding memory in patients with borderline personality disorder (BPD). Prior reports and anecdotal evidence suggests that patients with BPD are prone to false memories but this assumption has to been put to firm empirical test, yet. Memory accuracy and confidence was assessed in 20 BPD patients and 22 healthy controls using a visual variant of the false memory (Deese-Roediger-McDermott) paradigm which involved a negative and a positive-valenced picture. Groups did not differ regarding veridical item recognition. Importantly, patients did not display more false memories than controls. At trend level, borderline patients rated more items as new with high confidence compared to healthy controls. The results tentatively suggest that borderline patients show uncompromised visual memory functions and display no increased susceptibility for distorted memories. Copyright © 2013 Elsevier Ltd. All rights reserved.

How trait anxiety, interpretation bias and memory affect acquired fear in children learning about new animals.

PubMed

Field, Zoë C; Field, Andy P

2013-06-01

Cognitive models of vulnerability to anxiety propose that information processing biases such as interpretation bias play a part in the etiology and maintenance of anxiety disorders. However, at present little is known about the role of memory in information processing accounts of child anxiety. The current study investigates the relationships between interpretation biases, memory and fear responses when learning about new stimuli. Children (aged 8-11 years) were presented with ambiguous information regarding a novel animal, and their fear, interpretation bias, and memory for the information was measured. The main findings were: (1) trait anxiety and interpretation bias significantly predicted acquired fear; (2) interpretation bias did not significantly mediate the relationship between trait anxiety and acquired fear; (3) interpretation bias appeared to be a more important predictor of acquired fear than trait anxiety per se; and (4) the relationship between interpretation bias and acquired fear was not mediated by the number of negative memories but was mediated by the number of positive and false-positive memories. The findings suggest that information processing models of child anxiety need to explain the role of positive memory in the formation of fear responses.

Susceptibility to false memories in patients with ACoA aneurysm.

PubMed

Borsutzky, Sabine; Fujiwara, Esther; Brand, Matthias; Markowitsch, Hans J

2010-08-01

We examined ACoA patients regarding their susceptibility to a range of false memory phenomena. We targeted provoked confabulation, false recall and false recognition in the Deese-Roediger-McDermott-paradigm (DRM-paradigm) as well as false recognition in a mirror reading task. ACoA patients produced more provoked confabulations and more false recognition in mirror reading than comparison subjects. Conversely, false recall/false recognition in the DRM-paradigm were similar in patients and controls. Whereas the former two indices of false memories were correlated, no relationship was revealed with the DRM-paradigm. Our results suggest that rupture of ACoA aneurysm leads to an increased susceptibility to a subset of false memories types. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

False memory in aging resulting from self-referential processing.

PubMed

Rosa, Nicole M; Gutchess, Angela H

2013-11-01

Referencing the self is known to enhance accurate memory, but less is known about how the strategy affects false memory, particularly for highly self-relevant information. Because older adults are more prone to false memories, we tested whether self-referencing increased false memories with age. In 2 studies, older and younger adults rated adjectives for self-descriptiveness and later completed a surprise recognition test comprised of words rated previously for self-descriptiveness and novel lure words. Lure words were subsequently rated for self-descriptiveness in order to assess the impact of self-relevance on false memory. Study 2 introduced commonness judgments as a control condition, such that participants completed a recognition test on adjectives rated for commonness in addition to adjectives in the self-descriptiveness condition. Across both studies, findings indicate an increased response bias to self-referencing that increased hit rates for both older and younger adults but also increased false alarms as information became more self-descriptive, particularly for older adults. Although the present study supports previous literature showing a boost in memory for self-referenced information, the increase in false alarms, especially in older adults, highlights the potential for memory errors, particularly for information that is strongly related to the self.

True photographs and false memories.

PubMed

Lindsay, D Stephen; Hagen, Lisa; Read, J Don; Wade, Kimberley A; Garry, Maryanne

2004-03-01

Some trauma-memory-oriented psychotherapists advise clients to review old family photo albums to cue suspected "repressed" memories of childhood sexual abuse. Old photos might cue long-forgotten memories, but when combined with other suggestive influences they might also contribute to false memories. We asked 45 undergraduates to work at remembering three school-related childhood events (two true events provided by parents and one pseudoevent). By random assignment, 23 subjects were also given their school classes' group photos from the years of the to-be-recalled events as memory cues. As predicted, the rate of false-memory reports was dramatically higher in the photo condition than in the no-photo condition. Indeed, the rate of false-memory reports in the photo condition was substantially higher than the rate in any previously published study.

False Memories Are Not Surprising: The Subjective Experience of an Associative Memory Illusion

ERIC Educational Resources Information Center

Karpicke, Jeffrey D.; McCabe, David P.; Roediger, Henry L., III

2008-01-01

Four experiments examined subjective experience during retrieval in the DRM false memory paradigm [Deese, J. (1959). "On the prediction of occurrence of particular verbal intrusions in immediate recall." "Journal of Experimental Psychology," 58, 17-22; Roediger, H. L., & McDermott, K. B. (1995). "Creating false memories: Remembering words not…

Developmental Reversals in False Memory: Effects of Emotional Valence and Arousal

ERIC Educational Resources Information Center

Brainerd, C. J.; Holliday, R. E.; Reyna, V. F.; Yang, Y.; Toglia, M. P.

2010-01-01

Do the emotional valence and arousal of events distort children's memories? Do valence and arousal modulate counterintuitive age increases in false memory? We investigated those questions in children, adolescents, and adults using the Cornell/Cortland Emotion Lists, a word list pool that induces false memories and in which valence and arousal can…

What’s the Gist? The influence of schemas on the neural correlates underlying true and false memories

PubMed Central

Webb, Christina E.; Turney, Indira C.; Dennis, Nancy A.

2017-01-01

The current study used a novel scene paradigm to investigate the role of encoding schemas on memory. Specifically, the study examined the influence of a strong encoding schema on retrieval of both schematic and non-schematic information, as well as false memories for information associated with the schema. Additionally, the separate roles of recollection and familiarity in both veridical and false memory retrieval were examined. The study identified several novel results. First, while many common neural regions mediated both schematic and non-schematic retrieval success, schematic recollection exhibited greater activation in visual cortex and hippocampus, regions commonly shown to mediate detailed retrieval. More effortful cognitive control regions in the prefrontal and parietal cortices, on the other hand, supported non-schematic recollection, while lateral temporal cortices supported familiarity-based retrieval of non-schematic items. Second, both true and false recollection, as well as familiarity, were mediated by activity in left middle temporal gyrus, a region associated with semantic processing and retrieval of schematic gist. Moreover, activity in this region was greater for both false recollection and false familiarity, suggesting a greater reliance on lateral temporal cortices for retrieval of illusory memories, irrespective of memory strength. Consistent with previous false memory studies, visual cortex showed increased activity for true compared to false recollection, suggesting that visual cortices are critical for distinguishing between previously viewed targets and related lures at retrieval. Additionally, the absence of common visual activity between true and false retrieval suggests that, unlike previous studies utilizing visual stimuli, when false memories are predicated on schematic gist and not perceptual overlap, there is little reliance on visual processes during false memory retrieval. Finally, the medial temporal lobe exhibited an interesting dissociation, showing greater activity for true compared to false recollection, as well as for false compared to true familiarity. These results provided an indication as to how different types of items are retrieved when studied within a highly schematic context. Results both replicate and extend previous true and false memory findings, supporting the Fuzzy Trace Theory. PMID:27697593

What's the gist? The influence of schemas on the neural correlates underlying true and false memories.

PubMed

Webb, Christina E; Turney, Indira C; Dennis, Nancy A

2016-12-01

The current study used a novel scene paradigm to investigate the role of encoding schemas on memory. Specifically, the study examined the influence of a strong encoding schema on retrieval of both schematic and non-schematic information, as well as false memories for information associated with the schema. Additionally, the separate roles of recollection and familiarity in both veridical and false memory retrieval were examined. The study identified several novel results. First, while many common neural regions mediated both schematic and non-schematic retrieval success, schematic recollection exhibited greater activation in visual cortex and hippocampus, regions commonly shown to mediate detailed retrieval. More effortful cognitive control regions in the prefrontal and parietal cortices, on the other hand, supported non-schematic recollection, while lateral temporal cortices supported familiarity-based retrieval of non-schematic items. Second, both true and false recollection, as well as familiarity, were mediated by activity in left middle temporal gyrus, a region associated with semantic processing and retrieval of schematic gist. Moreover, activity in this region was greater for both false recollection and false familiarity, suggesting a greater reliance on lateral temporal cortices for retrieval of illusory memories, irrespective of memory strength. Consistent with previous false memory studies, visual cortex showed increased activity for true compared to false recollection, suggesting that visual cortices are critical for distinguishing between previously viewed targets and related lures at retrieval. Additionally, the absence of common visual activity between true and false retrieval suggests that, unlike previous studies utilizing visual stimuli, when false memories are predicated on schematic gist and not perceptual overlap, there is little reliance on visual processes during false memory retrieval. Finally, the medial temporal lobe exhibited an interesting dissociation, showing greater activity for true compared to false recollection, as well as for false compared to true familiarity. These results provided an indication as to how different types of items are retrieved when studied within a highly schematic context. Results both replicate and extend previous true and false memory findings, supporting the Fuzzy Trace Theory. Copyright © 2016 Elsevier Ltd. All rights reserved.

Individual differences in false memory from misinformation: cognitive factors.

PubMed

Zhu, Bi; Chen, Chuansheng; Loftus, Elizabeth F; Lin, Chongde; He, Qinghua; Chen, Chunhui; Li, He; Xue, Gui; Lu, Zhonglin; Dong, Qi

2010-07-01

This research investigated the cognitive correlates of false memories that are induced by the misinformation paradigm. A large sample of Chinese college students (N=436) participated in a misinformation procedure and also took a battery of cognitive tests. Results revealed sizable and systematic individual differences in false memory arising from exposure to misinformation. False memories were significantly and negatively correlated with measures of intelligence (measured with Raven's Advanced Progressive Matrices and Wechsler Adult Intelligence Scale), perception (Motor-Free Visual Perception Test, Change Blindness, and Tone Discrimination), memory (Wechsler Memory Scales and 2-back Working Memory tasks), and face judgement (Face Recognition and Facial Expression Recognition). These findings suggest that people with relatively low intelligence and poor perceptual abilities might be more susceptible to the misinformation effect.

Rapid induction of false memory for pictures.

PubMed

Weinstein, Yana; Shanks, David R

2010-07-01

Recognition of pictures is typically extremely accurate, and it is thus unclear whether the reconstructive nature of memory can yield substantial false recognition of highly individuated stimuli. A procedure for the rapid induction of false memories for distinctive colour photographs is proposed. Participants studied a set of object pictures followed by a list of words naming those objects, but embedded in the list were names of unseen objects. When subsequently shown full colour pictures of these unseen objects, participants consistently claimed that they had seen them, while discriminating with high accuracy between studied pictures and new pictures whose names did not appear in the misleading word list. These false memories can be reported with high confidence as well as the feeling of recollection. This new procedure allows the investigation of factors that influence false memory reports with ecologically valid stimuli and of the similarities and differences between true and false memories.

Thinking of critical words during study is unnecessary for false memory in the Deese, Roediger, and McDermott procedure.

PubMed

Seamon, John G; Lee, Ihno A; Toner, Sarah K; Wheeler, Rachel H; Goodkind, Madeleine S; Birch, Antoine D

2002-11-01

Do participants in the Deese, Roediger, and McDermott (DRM) procedure demonstrate false memory because they think of nonpresented critical words during study and confuse them with words that were actually presented? In two experiments, 160 participants studied eight visually presented DRM lists at a rate of 2 s or 5 s per word. Half of the participants rehearsed silently: the other half rehearsed overtly. Following study, the participants' memory for the lists was tested by recall or recognition. Typical false memory results were obtained for both memory measures. More important, two new results were observed. First, a large majority of the overt-rehearsal participants spontaneously rehearsed approximately half of the critical words during study. Second, critical-word rehearsal at study enhanced subsequent false recall, but it had no effect on false recognition or remember judgments for falsely recognized critical words. Thinking of critical words during study was unnecessary for producing false memory.

Mnemonic transmission, social contagion, and emergence of collective memory: Influence of emotional valence, group structure, and information distribution.

PubMed

Choi, Hae-Yoon; Kensinger, Elizabeth A; Rajaram, Suparna

2017-09-01

Social transmission of memory and its consequence on collective memory have generated enduring interdisciplinary interest because of their widespread significance in interpersonal, sociocultural, and political arenas. We tested the influence of 3 key factors-emotional salience of information, group structure, and information distribution-on mnemonic transmission, social contagion, and collective memory. Participants individually studied emotionally salient (negative or positive) and nonemotional (neutral) picture-word pairs that were completely shared, partially shared, or unshared within participant triads, and then completed 3 consecutive recalls in 1 of 3 conditions: individual-individual-individual (control), collaborative-collaborative (identical group; insular structure)-individual, and collaborative-collaborative (reconfigured group; diverse structure)-individual. Collaboration enhanced negative memories especially in insular group structure and especially for shared information, and promoted collective forgetting of positive memories. Diverse group structure reduced this negativity effect. Unequally distributed information led to social contagion that creates false memories; diverse structure propagated a greater variety of false memories whereas insular structure promoted confidence in false recognition and false collective memory. A simultaneous assessment of network structure, information distribution, and emotional valence breaks new ground to specify how network structure shapes the spread of negative memories and false memories, and the emergence of collective memory. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Emotions and false memories: valence or arousal?

PubMed

Corson, Yves; Verrier, Nadège

2007-03-01

The effects of mood on false memories have not been studied systematically until recently. Some results seem to indicate that negative mood may reduce false recall and thus suggest an influence of emotional valence on false memory. The present research tested the effects of both valence and arousal on recall and recognition and indicates that the effect is actually due to arousal. In fact, whether participants' mood is positive, negative, or neutral, false memories are significantly more frequent under conditions of high arousal than under conditions of low arousal.

Working memory predicts the rejection of false memories.

PubMed

Leding, Juliana K

2012-01-01

The relationship between working memory capacity (WMC) and false memories in the memory conjunction paradigm was explored. Previous research using other paradigms has shown that individuals high in WMC are not as likely to experience false memories as low-WMC individuals, the explanation being that high-WMC individuals are better able to engage in source monitoring. In the memory conjunction paradigm participants are presented at study with parent words (e.g., eyeglasses, whiplash). At test, in addition to being presented with targets and foils, participants are presented with lures that are composed of previously studied features (e.g., eyelash). It was found that high-WMC individuals had lower levels of false recognition than low-WMC individuals. Furthermore, recall-to-reject responses were analysed (e.g., "I know I didn't see eyelash because I remember seeing eyeglasses") and it was found that high-WMC individuals were more likely to utilise this memory editing strategy, providing direct evidence that one reason that high-WMC individuals are not as prone to false memories is because they are better able to engage in source monitoring.

False memory for context and true memory for context similarly activate the parahippocampal cortex.

PubMed

Karanian, Jessica M; Slotnick, Scott D

2017-06-01

The role of the parahippocampal cortex is currently a topic of debate. One view posits that the parahippocampal cortex specifically processes spatial layouts and sensory details (i.e., the visual-spatial processing view). In contrast, the other view posits that the parahippocampal cortex more generally processes spatial and non-spatial contexts (i.e., the general contextual processing view). A large number of studies have found that true memories activate the parahippocampal cortex to a greater degree than false memories, which would appear to support the visual-spatial processing view as true memories are typically associated with greater visual-spatial detail than false memories. However, in previous studies, contextual details were also greater for true memories than false memories. Thus, such differential activity in the parahippocampal cortex may have reflected differences in contextual processing, which would challenge the visual-spatial processing view. In the present functional magnetic resonance imaging (fMRI) study, we employed a source memory paradigm to investigate the functional role of the parahippocampal cortex during true memory and false memory for contextual information to distinguish between the visual-spatial processing view and the general contextual processing view. During encoding, abstract shapes were presented to the left or right of fixation. During retrieval, old shapes were presented at fixation and participants indicated whether each shape was previously on the "left" or "right" followed by an "unsure", "sure", or "very sure" confidence rating. The conjunction of confident true memories for context and confident false memories for context produced activity in the parahippocampal cortex, which indicates that this region is associated with contextual processing. Furthermore, the direct contrast of true memory and false memory produced activity in the visual cortex but did not produce activity in the parahippocampal cortex. The present evidence suggests that the parahippocampal cortex is associated with general contextual processing rather than only being associated with visual-spatial processing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Messing with Your Mind.

ERIC Educational Resources Information Center

Murphy, Pat; Doherty, Paul

1998-01-01

Research has demonstrated that memory is prone to distortion and is occasionally untrustworthy. Explores the reasons for false memories and explains that memories are vulnerable to postevent information, which can be integrated into memories. False memories can also come from leading questions, word associations, and unconscious editing by the…

False recall is reduced by damage to the ventromedial prefrontal cortex: implications for understanding the neural correlates of schematic memory.

PubMed

Warren, David E; Jones, Samuel H; Duff, Melissa C; Tranel, Daniel

2014-05-28

Schematic memory, or contextual knowledge derived from experience (Bartlett, 1932), benefits memory function by enhancing retention and speeding learning of related information (Bransford and Johnson, 1972; Tse et al., 2007). However, schematic memory can also promote memory errors, producing false memories. One demonstration is the "false memory effect" of the Deese-Roediger-McDermott (DRM) paradigm (Roediger and McDermott, 1995): studying words that fit a common schema (e.g., cold, blizzard, winter) often produces memory for a nonstudied word (e.g., snow). We propose that frontal lobe regions that contribute to complex decision-making processes by weighting various alternatives, such as ventromedial prefrontal cortex (vmPFC), may also contribute to memory processes by weighting the influence of schematic knowledge. We investigated the role of human vmPFC in false memory by combining a neuropsychological approach with the DRM task. Patients with vmPFC lesions (n = 7) and healthy comparison participants (n = 14) studied word lists that excluded a common associate (the critical item). Recall and recognition tests revealed expected high levels of false recall and recognition of critical items by healthy participants. In contrast, vmPFC patients showed consistently reduced false recall, with significantly fewer intrusions of critical items. False recognition was also marginally reduced among vmPFC patients. Our findings suggest that vmPFC increases the influence of schematically congruent memories, a contribution that may be related to the role of the vmPFC in decision making. These novel neuropsychological results highlight a role for the vmPFC as part of a memory network including the medial temporal lobes and hippocampus (Andrews-Hanna et al., 2010). Copyright © 2014 the authors 0270-6474/14/347677-06$15.00/0.

False Recall Is Reduced by Damage to the Ventromedial Prefrontal Cortex: Implications for Understanding the Neural Correlates of Schematic Memory

PubMed Central

Jones, Samuel H.; Duff, Melissa C.; Tranel, Daniel

2014-01-01

Schematic memory, or contextual knowledge derived from experience (Bartlett, 1932), benefits memory function by enhancing retention and speeding learning of related information (Bransford and Johnson, 1972; Tse et al., 2007). However, schematic memory can also promote memory errors, producing false memories. One demonstration is the “false memory effect” of the Deese–Roediger–McDermott (DRM) paradigm (Roediger and McDermott, 1995): studying words that fit a common schema (e.g., cold, blizzard, winter) often produces memory for a nonstudied word (e.g., snow). We propose that frontal lobe regions that contribute to complex decision-making processes by weighting various alternatives, such as ventromedial prefrontal cortex (vmPFC), may also contribute to memory processes by weighting the influence of schematic knowledge. We investigated the role of human vmPFC in false memory by combining a neuropsychological approach with the DRM task. Patients with vmPFC lesions (n = 7) and healthy comparison participants (n = 14) studied word lists that excluded a common associate (the critical item). Recall and recognition tests revealed expected high levels of false recall and recognition of critical items by healthy participants. In contrast, vmPFC patients showed consistently reduced false recall, with significantly fewer intrusions of critical items. False recognition was also marginally reduced among vmPFC patients. Our findings suggest that vmPFC increases the influence of schematically congruent memories, a contribution that may be related to the role of the vmPFC in decision making. These novel neuropsychological results highlight a role for the vmPFC as part of a memory network including the medial temporal lobes and hippocampus (Andrews-Hanna et al., 2010). PMID:24872571

On the susceptibility of adaptive memory to false memory illusions.

PubMed

Howe, Mark L; Derbish, Mary H

2010-05-01

Previous research has shown that survival-related processing of word lists enhances retention for that material. However, the claim that survival-related memories are more accurate has only been examined when true recall and recognition of neutral material has been measured. In the current experiments, we examined the adaptive memory superiority effect for different types of processing and material, measuring accuracy more directly by comparing true and false recollection rates. Survival-related information and processing was examined using word lists containing backward associates of neutral, negative, and survival-related critical lures and type of processing (pleasantness, moving, survival) was varied using an incidental memory paradigm. Across four experiments, results showed that survival-related words were more susceptible than negative and neutral words to the false memory illusion and that processing information in terms of its relevance to survival independently increased this susceptibility to the false memory illusion. Overall, although survival-related processing and survival-related information resulted in poorer, not more accurate, memory, such inaccuracies may have adaptive significance. These findings are discussed in the context of false memory research and recent theories concerning the importance of survival processing and the nature of adaptive memory. Copyright 2009 Elsevier B.V. All rights reserved.

Memory Distortion and Its Avoidance: An Event-Related Potentials Study on False Recognition and Correct Rejection

PubMed Central

Beato, Maria Soledad

2016-01-01

Memory researchers have long been captivated by the nature of memory distortions and have made efforts to identify the neural correlates of true and false memories. However, the underlying mechanisms of avoiding false memories by correctly rejecting related lures remains underexplored. In this study, we employed a variant of the Deese/Roediger-McDermott paradigm to explore neural signatures of committing and avoiding false memories. ERP were obtained for True recognition, False recognition, Correct rejection of new items, and, more importantly, Correct rejection of related lures. With these ERP data, early-frontal, left-parietal, and late right-frontal old/new effects (associated with familiarity, recollection, and monitoring processes, respectively) were analysed. Results indicated that there were similar patterns for True and False recognition in all three old/new effects analysed in our study. Also, False recognition and Correct rejection of related lures activities seemed to share common underlying familiarity-based processes. The ERP similarities between False recognition and Correct rejection of related lures disappeared when recollection processes were examined because only False recognition presented a parietal old/new effect. This finding supported the view that actual false recollections underlie false memories, providing evidence consistent with previous behavioural research and with most ERP and neuroimaging studies. Later, with the onset of monitoring processes, False recognition and Correct rejection of related lures waveforms presented, again, clearly dissociated patterns. Specifically, False recognition and True recognition showed more positive going patterns than Correct rejection of related lures signal and Correct rejection of new items signature. Since False recognition and Correct rejection of related lures triggered familiarity-recognition processes, our results suggest that deciding which items are studied is based more on recollection processes, which are later supported by monitoring processes. Results are discussed in terms of Activation-Monitoring Framework and Fuzzy Trace-Theory, the most prominent explanatory theories of false memory raised with the Deese/Roediger-McDermott paradigm. PMID:27711125

Memory Distortion and Its Avoidance: An Event-Related Potentials Study on False Recognition and Correct Rejection.

PubMed

Cadavid, Sara; Beato, Maria Soledad

2016-01-01

Memory researchers have long been captivated by the nature of memory distortions and have made efforts to identify the neural correlates of true and false memories. However, the underlying mechanisms of avoiding false memories by correctly rejecting related lures remains underexplored. In this study, we employed a variant of the Deese/Roediger-McDermott paradigm to explore neural signatures of committing and avoiding false memories. ERP were obtained for True recognition, False recognition, Correct rejection of new items, and, more importantly, Correct rejection of related lures. With these ERP data, early-frontal, left-parietal, and late right-frontal old/new effects (associated with familiarity, recollection, and monitoring processes, respectively) were analysed. Results indicated that there were similar patterns for True and False recognition in all three old/new effects analysed in our study. Also, False recognition and Correct rejection of related lures activities seemed to share common underlying familiarity-based processes. The ERP similarities between False recognition and Correct rejection of related lures disappeared when recollection processes were examined because only False recognition presented a parietal old/new effect. This finding supported the view that actual false recollections underlie false memories, providing evidence consistent with previous behavioural research and with most ERP and neuroimaging studies. Later, with the onset of monitoring processes, False recognition and Correct rejection of related lures waveforms presented, again, clearly dissociated patterns. Specifically, False recognition and True recognition showed more positive going patterns than Correct rejection of related lures signal and Correct rejection of new items signature. Since False recognition and Correct rejection of related lures triggered familiarity-recognition processes, our results suggest that deciding which items are studied is based more on recollection processes, which are later supported by monitoring processes. Results are discussed in terms of Activation-Monitoring Framework and Fuzzy Trace-Theory, the most prominent explanatory theories of false memory raised with the Deese/Roediger-McDermott paradigm.

Correcting false memories: Errors must be noticed and replaced.

PubMed

Mullet, Hillary G; Marsh, Elizabeth J

2016-04-01

Memory can be unreliable. For example, after reading The new baby stayed awake all night, people often misremember that the new baby cried all night (Brewer, 1977); similarly, after hearing bed, rest, and tired, people often falsely remember that sleep was on the list (Roediger & McDermott, 1995). In general, such false memories are difficult to correct, persisting despite warnings and additional study opportunities. We argue that errors must first be detected to be corrected; consistent with this argument, two experiments showed that false memories were nearly eliminated when conditions facilitated comparisons between participants' errors and corrective feedback (e.g., immediate trial-by-trial feedback that allowed direct comparisons between their responses and the correct information). However, knowledge that they had made an error was insufficient; unless the feedback message also contained the correct answer, the rate of false memories remained relatively constant. On the one hand, there is nothing special about correcting false memories: simply labeling an error as "wrong" is also insufficient for correcting other memory errors, including misremembered facts or mistranslations. However, unlike these other types of errors--which often benefit from the spacing afforded by delayed feedback--false memories require a special consideration: Learners may fail to notice their errors unless the correction conditions specifically highlight them.

False Memory in Aging Resulting From Self-Referential Processing

PubMed Central

2013-01-01

Objectives. Referencing the self is known to enhance accurate memory, but less is known about how the strategy affects false memory, particularly for highly self-relevant information. Because older adults are more prone to false memories, we tested whether self-referencing increased false memories with age. Method. In 2 studies, older and younger adults rated adjectives for self-descriptiveness and later completed a surprise recognition test comprised of words rated previously for self-descriptiveness and novel lure words. Lure words were subsequently rated for self-descriptiveness in order to assess the impact of self-relevance on false memory. Study 2 introduced commonness judgments as a control condition, such that participants completed a recognition test on adjectives rated for commonness in addition to adjectives in the self-descriptiveness condition. Results. Across both studies, findings indicate an increased response bias to self-referencing that increased hit rates for both older and younger adults but also increased false alarms as information became more self-descriptive, particularly for older adults. Discussion. Although the present study supports previous literature showing a boost in memory for self-referenced information, the increase in false alarms, especially in older adults, highlights the potential for memory errors, particularly for information that is strongly related to the self. PMID:23576449

How does negative emotion cause false memories?

PubMed

Brainerd, C J; Stein, L M; Silveira, R A; Rohenkohl, G; Reyna, V F

2008-09-01

Remembering negative events can stimulate high levels of false memory, relative to remembering neutral events. In experiments in which the emotional valence of encoded materials was manipulated with their arousal levels controlled, valence produced a continuum of memory falsification. Falsification was highest for negative materials, intermediate for neutral materials, and lowest for positive materials. Conjoint-recognition analysis produced a simple process-level explanation: As one progresses from positive to neutral to negative valence, false memory increases because (a) the perceived meaning resemblance between false and true items increases and (b) subjects are less able to use verbatim memories of true items to suppress errors.

The False Memory and the Mirror Effects: The Role of Familiarity and Backward Association in Creating False Recollections

ERIC Educational Resources Information Center

Anaki, D.; Faran, Y.; Ben-Shalom, D.; Henik, A.

2005-01-01

The mirror effect refers to a phenomenon where the hit rate is higher for low frequency words while the false alarm rate is higher for high frequency distractors. Using a false memory paradigm (Roediger & McDermott, 1995), we examined whether false memory for non-presented lures would be influenced by the lure's familiarity. The results revealed…

Emotion and false memory: The context-content paradox.

PubMed

Bookbinder, S H; Brainerd, C J

2016-12-01

False memories are influenced by a variety of factors, but emotion is a variable of special significance, for theoretical and practical reasons. Interestingly, emotion's effects on false memory depend on whether it is embedded in the content of to-be-remembered events or in our moods, where mood is an aspect of the context in which events are encoded. We sketch the theoretical basis for this content-context dissociation and then review accumulated evidence that content and context effects are indeed different. Paradoxically, we find that in experiments on spontaneous and implanted false memories, negatively valenced content foments distortion, but negatively valenced moods protect against it. In addition, correlational data show that enduring negative natural moods (e.g., depression) foment false memory. Current opponent-process models of false memory, such as fuzzy-trace theory, are able to explain the content-context dissociation: Variations in emotional content primarily affect memory for the gist of events, whereas variations in emotional context primarily affect memory for events' exact verbatim form. Important questions remain about how these effects are modulated by variations in memory tests and in arousal. Promising methods of tackling those questions are outlined, especially designs that separate the gist and verbatim influences of emotion. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A Brighter Side to Memory Illusions: False Memories Prime Children's and Adults' Insight-Based Problem Solving

ERIC Educational Resources Information Center

Howe, Mark L.; Garner, Sarah R.; Charlesworth, Monica; Knott, Lauren

2011-01-01

Can false memories have a positive consequence on human cognition? In two experiments, we investigated whether false memories could prime insight problem-solving tasks. Children and adults were asked to solve compound remote associate task (CRAT) problems, half of which had been primed by the presentation of Deese/Roediger-McDermott (DRM) lists…

Developmentally invariant dissociations in children's true and false memories: not all relatedness is created equal.

PubMed

Howe, Mark L

2006-01-01

The role of categorical versus associative relations in 5-, 7-, and 11-year-old children's true and false memories was examined using the Deese-Roediger-McDermott (DRM) paradigm and categorized lists of pictures or words with or without category labels as primes. For true items, recall increased with age and categorized lists were better recalled than DRM lists. For false items, recall increased with age except for picture lists, there were no differences between categorized and DRM lists and no effect of priming, and there were fewer false memories for pictures than words. Like adults, children's false memories are based on associative not thematic relations, whereas their veridical memories depend on both. This new, developmentally invariant dissociation is consistent with knowledge- and resource-based models of memory development.

The effects of increasing semantic-associate list length on the Deese-Roediger-McDermott false recognition memory: Dual false-memory process in retrieval from sub- and supraspan lists.

PubMed

Jou, Jerwen; Arredondo, Mario L; Li, Cheng; Escamilla, Eric E; Zuniga, Richard

2017-10-01

In this study, the number of semantic associates in Deese-Roediger-McDermott (DRM) lists was varied from 4 to 14 in a modified Sternberg paradigm. The false alarm (FA) and correct rejection (CR) reaction time (RT)/memory-set size (MSS) functions of critical lures showed a cross-over interaction at approximately MSS 7, suggesting a reversal of the relative dominance between these two responses to the critical lure at this point and also indicating the location of the boundary between the sub- and supraspan MSS. For the subspan lists, FA to critical lures was slower than CR, suggesting a slow, strategic mechanism driving the false memory. Conversely, for the supraspan lists, critical lure FA was faster than its CR, suggesting a spontaneous mechanism driving the false memory. Results of two experiments showed that an automatic, fast, and a slow, controlled process could be error-prone or error-corrective, depending on the length of the DRM memory list. Thus there is a dual retrieval process in false memory as in true memory. The findings can be explained by both the activation/monitoring and the fuzzy-trace theories.

The ADRA2B gene in the production of false memories for affective information in healthy female volunteers.

PubMed

Fairfield, Beth; Mammarella, Nicola; Di Domenico, Alberto; D'Aurora, Marco; Stuppia, Liborio; Gatta, Valentina

2017-08-30

False memories are common memory distortions in everyday life and seem to increase with affectively connoted complex information. In line with recent studies showing a significant interaction between the noradrenergic system and emotional memory, we investigated whether healthy volunteer carriers of the deletion variant of the ADRA2B gene that codes for the α2b-adrenergic receptor are more prone to false memories than non-carriers. In this study, we collected genotype data from 212 healthy female volunteers; 91 ADRA2B carriers and 121 non-carriers. To assess gene effects on false memories for affective information, factorial mixed model analysis of variances (ANOVAs) were conducted with genotype as the between-subjects factor and type of memory error as the within-subjects factor. We found that although carriers and non-carriers made comparable numbers of false memory errors, they showed differences in the direction of valence biases, especially for inferential causal errors. Specifically, carriers produced fewer causal false memory errors for scripts with a negative outcome, whereas non-carriers showed a more general emotional effect and made fewer causal errors with both positive and negative outcomes. These findings suggest that putatively higher levels of noradrenaline in deletion carriers may enhance short-term consolidation of negative information and lead to fewer memory distortions when facing negative events. Copyright © 2017 Elsevier B.V. All rights reserved.

Formation of spatial and nonspatial memory in different condensed versions of short-term learning in Morris water maze.

PubMed

Zots, M A; Ivashkina, O I; Ivanova, A A; Anokhin, K V

2014-03-01

We studied the formation of spatial and nonspatial memory in mice during learning in three different condensed versions of Morris water maze task. Learning in combined version caused the formation of both spatial and nonspatial memory, whereas learning in condensed versions (spatial and nonspatial) led to memory formation specific for the version.

Lexical Association and False Memory for Words in Two Cultures

ERIC Educational Resources Information Center

Lee, Yuh-Shiow; Chiang, Wen-Chi; Hung, Hsu-Ching

2008-01-01

This study examined the relationship between language experience and false memory produced by the DRM paradigm. The word lists used in Stadler, et al. (Memory & Cognition, 27, 494-500, 1999) were first translated into Chinese. False recall and false recognition for critical non-presented targets were then tested on a group of Chinese users.…

Factors that influence the generation of autobiographical memory conjunction errors.

PubMed

Devitt, Aleea L; Monk-Fromont, Edwin; Schacter, Daniel L; Addis, Donna Rose

2016-01-01

The constructive nature of memory is generally adaptive, allowing us to efficiently store, process and learn from life events, and simulate future scenarios to prepare ourselves for what may come. However, the cost of a flexibly constructive memory system is the occasional conjunction error, whereby the components of an event are authentic, but the combination of those components is false. Using a novel recombination paradigm, it was demonstrated that details from one autobiographical memory (AM) may be incorrectly incorporated into another, forming AM conjunction errors that elude typical reality monitoring checks. The factors that contribute to the creation of these conjunction errors were examined across two experiments. Conjunction errors were more likely to occur when the corresponding details were partially rather than fully recombined, likely due to increased plausibility and ease of simulation of partially recombined scenarios. Brief periods of imagination increased conjunction error rates, in line with the imagination inflation effect. Subjective ratings suggest that this inflation is due to similarity of phenomenological experience between conjunction and authentic memories, consistent with a source monitoring perspective. Moreover, objective scoring of memory content indicates that increased perceptual detail may be particularly important for the formation of AM conjunction errors.

Everyday false memories in older persons with depressive disorder.

PubMed

Sejunaite, Karolina; Lanza, Claudia; Riepe, Matthias W

2018-03-01

Generally we tend to think that memory in daily living is complete and accurate in healthy persons. However, current memory research has revealed inconspicuous memory faults. Rarely omissions and distortions of memory are researched with tasks resembling everyday life. We investigated healthy older control subjects (HC) and patients with depressive disorder (DD). Cognitive function was assessed with a comprehensive neuropsychological test battery and mood with the Montgomery-Asberg Depression Scale (MADRS). We assessed everyday veridical and distorted memories on showing participants original news and commercials. In most aspects of attention, executive functions, and memory, patients with DD performed worse than HC. Regarding memory content on viewing news or commercials the difference between patients with DD and HC was more pronounced for false memory content than for veridical memory content. Linear regression analysis showed the extent of false memory content being associated with mental flexibility as assessed with the Trail Making Test and mood as assessed with the MADRS for both information obtained on viewing news and commercials. Increase of false memories impedes overall accuracy of memory more than decrease of veridical memories in older persons with depressive disorder. Diminished executive functions and depressive mood partly explain these memory distortions. Copyright © 2018 Elsevier B.V. All rights reserved.

Improving the identification accuracy of senior witnesses: do prelineup questions and sequential testing help?

PubMed

Memon, Amina; Gabbert, Fiona

2003-04-01

Eyewitness research has identified sequential lineup testing as a way of reducing false lineup choices while maintaining accurate identifications. The authors examined the usefulness of this procedure for reducing false choices in older adults. Young and senior witnesses viewed a crime video and were later presented with target present orabsent lineups in a simultaneous or sequential format. In addition, some participants received prelineup questions about their memory for a perpetrator's face and about their confidence in their ability to identify the culprit or to correctly reject the lineup. The sequential lineup reduced false choosing rates among young and older adults in target-absent conditions. In target-present conditions, sequential testing significantly reduced the correct identification rate in both age groups.

Recollection Rejection: How Children Edit Their False Memories.

ERIC Educational Resources Information Center

Brainerd, C. J.; Reyna, V. F.

2002-01-01

Presents new measure of children's use of an editing operation that suppresses false memories by accessing verbatim traces of true events. Application of the methodology showed that false-memory editing increased dramatically between early and middle childhood. Measure reacted appropriately to experimental manipulations. Developmental reductions…

Lateralised sleep spindles relate to false memory generation.

PubMed

Shaw, John J; Monaghan, Padraic

2017-12-01

Sleep is known to enhance false memories: After presenting participants with lists of semantically related words, sleeping before recalling these words results in a greater acceptance of unseen "lure" words related in theme to previously seen words. Furthermore, the right hemisphere (RH) seems to be more prone to false memories than the left hemisphere (LH). In the current study, we investigated the sleep architecture associated with these false memory and lateralisation effects in a nap study. Participants viewed lists of related words, then stayed awake or slept for approximately 90min, and were then tested for recognition of previously seen-old, unseen-new, or unseen-lure words presented either to the LH or RH. Sleep increased acceptance of unseen-lure words as previously seen compared to the wake group, particularly for RH presentations of word lists. RH lateralised stage 2 sleep spindle density relative to the LH correlated with this increase in false memories, suggesting that RH sleep spindles enhanced false memories in the RH. Copyright © 2017 Elsevier Ltd. All rights reserved.

Can false memories be corrected by feedback in the DRM paradigm?

PubMed

McConnell, Melissa D; Hunt, R Reed

2007-07-01

Normal processes of comprehension frequently yield false memories as an unwanted by-product. The simple paradigm now known as the Deese/Roediger-McDermott (DRM) paradigm takes advantage of this fact and has been used to reliably produce false memory for laboratory study. Among the findings from past research is the difficulty of preventing false memories in this paradigm. The purpose of the present experiments was to examine the effectiveness of feedback in correcting false memories. Two experiments were conducted, in which participants recalled DRM lists and either received feedback on their performance or did not. A subsequent recall test was administered to assess the effect of feedback. The results showed promising effects of feedback: Feedback enhanced both error correction and the propagation of correct recall. The data replicated other data of studies that have shown substantial error perseveration following feedback. These data also provide new information on the occurrence of errors following feedback. The results are discussed in terms of the activation-monitoring theory of false memory.

A historical note on false traumatic memories.

PubMed

Rosen, Gerald M; Sageman, Marc; Loftus, Elizabeth

2004-01-01

Unhampered by current ethical standards and human subject committees, H. Bernheim (1889) created a false memory of a horrific traumatic event. Bernheim also demonstrated his subject's willingness to discuss the implanted memory with a representative of the law. Bernheim's work represents the first documented case of an implanted false traumatic memory, with direct relevance to contemporary debates. Copyright 2003 Wiley Periodicals, Inc. J Clin Psychol.

Murder Must Memorize

PubMed Central

Brainerd, C. J.

2013-01-01

Memory reports usually provide the evidence that is most determinative of guilt or innocence in criminal proceedings—including in the most serious proceedings, capital murder trials. Thus, memory research is bedrock science when it comes to the reliability of legal evidence, and expert testimony on such research is a linchpin of just verdicts. This principle is illustrated with a capital murder trial in which several of the most powerful forms of memory distortion were present (e.g., phantom recollections, robust interrogation methods that stimulate false self-incrimination). A key question before the jury, whether to regard the defendant’s confession as true or false, turned on a theoretical principle that is used to explain memory distortion in the laboratory, the verbatim-gist distinction, and on research showing that it is possible to create false memories that embody the gist of experience. The scientific testimony focused on instances in which false gist memories had been created under controlled conditions (e.g., of having been lost in a mall, of receiving surgery for a fictitious injury), as well as on real-life examples of false memory for the gist experience (e.g., recovered memories of sexual abuse, alien abduction memories). The defendant was found innocent of capital murder. PMID:23638648

True Memory, False Memory, and Subjective Recollection Deficits after Focal Parietal Lobe Lesions

PubMed Central

Drowos, David B.; Berryhill, Marian; André, Jessica M.; Olson, Ingrid R.

2010-01-01

Objective There is mounting evidence that the posterior parietal cortex (PPC) plays an important role in episodic memory. We previously found that patients with PPC damage exhibit retrieval-related episodic memory deficits. Our objective was to assess whether parietal lobe damage affects episodic memory on a different task: the Deese-Roediger-McDermott (DRM) false-memory paradigm. Method Two patients with bilateral PPC damage and matched controls were tested. In Experiment 1, the task was to remember words; in Experiment 2 the task was to remember pictures of common objects. Prior studies have shown that normal participants have high levels of false memory to words, low levels to pictures. Results The patients exhibited significantly lower levels of false memory to words. The patients' false memories were accompanied by reduced levels of recollection, as tested by a Remember/Know procedure. It is unlikely that a failure of gist processing accounts for these results, as patients accurately remembered thematic elements of short vignettes, but failed to remember details. These results support the view that portions of the PPC play a critical role in objective and subjective aspects of recollection. PMID:20604621

The semantics of emotion in false memory.

PubMed

Brainerd, C J; Bookbinder, S H

2018-03-26

The emotional valence of target information has been a centerpiece of recent false memory research, but in most experiments, it has been confounded with emotional arousal. We sought to clarify the results of such research by identifying a shared mathematical relation between valence and arousal ratings in commonly administered normed materials. That relation was then used to (a) decide whether arousal as well as valence influences false memory when they are confounded and to (b) determine whether semantic properties that are known to affect false memory covary with valence and arousal ratings. In Study 1, we identified a quadratic relation between valence and arousal ratings of words and pictures that has 2 key properties: Arousal increases more rapidly as function of negative valence than positive valence, and hence, a given level of negative valence is more arousing than the same level of positive valence. This quadratic function predicts that if arousal as well as valence affects false memory when they are confounded, false memory data must have certain fine-grained properties. In Study 2, those properties were absent from norming data for the Cornell-Cortland Emotional Word Lists, indicating that valence but not arousal affects false memory in those norms. In Study 3, we tested fuzzy-trace theory's explanation of that pattern: that valence ratings are positively related to semantic properties that are known to increase false memory, but arousal ratings are not. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Actually, a picture is worth less than 45 words: narratives produce more false memories than photographs do.

PubMed

Garry, Maryanne; Wade, Kimberley A

2005-04-01

Most memory "implantation" studies have elicited false memories by using fake narratives. Recently, Wade, Garry, Read, and Lindsay (2002) showed that doctored photographs can be used to create false childhood memories in adults. Fifty percent of Wade et al.'s sample reported details of taking a childhood hot air balloon ride, although they had never been in a balloon. In this experiment, we investigated whether photos or narratives influence memory more than the other. We exposed subjects to either a fake photograph or a fake narrative of a childhood hot air balloon ride. Subjects tried to remember the false event and three real events over 1 week. Narratives were more likely to produce false memory reports than were photos. We offer a fluency-based account of our results and suggest that narratives promote more familiarity in subjects than do photographs.

Adaptive false memory: Imagining future scenarios increases false memories in the DRM paradigm.

PubMed

Dewhurst, Stephen A; Anderson, Rachel J; Grace, Lydia; van Esch, Lotte

2016-10-01

Previous research has shown that rating words for their relevance to a future scenario enhances memory for those words. The current study investigated the effect of future thinking on false memory using the Deese/Roediger-McDermott (DRM) procedure. In Experiment 1, participants rated words from 6 DRM lists for relevance to a past or future event (with or without planning) or in terms of pleasantness. In a surprise recall test, levels of correct recall did not vary between the rating tasks, but the future rating conditions led to significantly higher levels of false recall than the past and pleasantness conditions did. Experiment 2 found that future rating led to higher levels of false recognition than did past and pleasantness ratings but did not affect correct recognition. The effect in false recognition was, however, eliminated when DRM items were presented in random order. Participants in Experiment 3 were presented with both DRM lists and lists of unrelated words. Future rating increased levels of false recognition for DRM lures but did not affect correct recognition for DRM or unrelated lists. The findings are discussed in terms of the view that false memories can be associated with adaptive memory functions.

Astrocyte glycogen and lactate: New insights into learning and memory mechanisms.

PubMed

Alberini, Cristina M; Cruz, Emmanuel; Descalzi, Giannina; Bessières, Benjamin; Gao, Virginia

2018-06-01

Memory, the ability to retain learned information, is necessary for survival. Thus far, molecular and cellular investigations of memory formation and storage have mainly focused on neuronal mechanisms. In addition to neurons, however, the brain comprises other types of cells and systems, including glia and vasculature. Accordingly, recent experimental work has begun to ask questions about the roles of non-neuronal cells in memory formation. These studies provide evidence that all types of glial cells (astrocytes, oligodendrocytes, and microglia) make important contributions to the processing of encoded information and storing memories. In this review, we summarize and discuss recent findings on the critical role of astrocytes as providers of energy for the long-lasting neuronal changes that are necessary for long-term memory formation. We focus on three main findings: first, the role of glucose metabolism and the learning- and activity-dependent metabolic coupling between astrocytes and neurons in the service of long-term memory formation; second, the role of astrocytic glucose metabolism in arousal, a state that contributes to the formation of very long-lasting and detailed memories; and finally, in light of the high energy demands of the brain during early development, we will discuss the possible role of astrocytic and neuronal glucose metabolisms in the formation of early-life memories. We conclude by proposing future directions and discussing the implications of these findings for brain health and disease. Astrocyte glycogenolysis and lactate play a critical role in memory formation. Emotionally salient experiences form strong memories by recruiting astrocytic β2 adrenergic receptors and astrocyte-generated lactate. Glycogenolysis and astrocyte-neuron metabolic coupling may also play critical roles in memory formation during development, when the energy requirements of brain metabolism are at their peak. © 2017 Wiley Periodicals, Inc.

Amphetamine increases errors during episodic memory retrieval.

PubMed

Ballard, Michael Edward; Gallo, David A; de Wit, Harriet

2014-02-01

Moderate doses of stimulant drugs are known to enhance memory encoding and consolidation, but their effects on memory retrieval have not been explored in depth. In laboratory animals, stimulants seem to improve retrieval of emotional memories, but comparable studies have not been carried out in humans. In the present study, we examined the effects of dextroamphetamine (AMP) on retrieval of emotional and unemotional stimuli in healthy young adults, using doses that enhanced memory formation when administered before encoding in our previous study. During 3 sessions, healthy volunteers (n = 31) received 2 doses of AMP (10 and 20 mg) and placebo in counterbalanced order under double-blind conditions. During each session, they first viewed emotional and unemotional pictures and words in a drug-free state, and then 2 days later their memory was tested, 1 hour after AMP or placebo administration. Dextroamphetamine did not affect the number of emotional or unemotional stimuli remembered, but both doses increased recall intrusions and false recognition. Dextroamphetamine (20 mg) also increased the number of positively rated picture descriptions and words generated during free recall. These data provide the first evidence that therapeutic range doses of stimulant drugs can increase memory retrieval errors. The ability of AMP to positively bias recollection of prior events could contribute to its potential for abuse.

Amphetamine Increases Errors During Episodic Memory Retrieval

PubMed Central

Ballard, Michael Edward; Gallo, David A.; de Wit, Harriet

2014-01-01

Moderate doses of stimulant drugs are known to enhance memory encoding and consolidation, but their effects on memory retrieval have not been explored in depth. In laboratory animals, stimulants seem to improve retrieval of emotional memories, but comparable studies have not been carried out in humans. In the present study, we examined the effects of dextroamphetamine (AMP) on retrieval of emotional and unemotional stimuli in healthy young adults, using doses that enhanced memory formation when administered before encoding in our previous study. During 3 sessions, healthy volunteers (n = 31) received 2 doses of AMP (10 and 20 mg) and placebo in counter-balanced order under double-blind conditions. During each session, they first viewed emotional and unemotional pictures and words in a drug-free state, and then 2 days later their memory was tested, 1 hour after AMP or placebo administration. Dextroamphetamine did not affect the number of emotional or unemotional stimuli remembered, but both doses increased recall intrusions and false recognition. Dextroamphetamine (20 mg) also increased the number of positively rated picture descriptions and words generated during free recall. These data provide the first evidence that therapeutic range doses of stimulant drugs can increase memory retrieval errors. The ability of AMP to positively bias recollection of prior events could contribute to its potential for abuse. PMID:24135845

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.

PubMed

Jou, Jerwen; Escamilla, Eric E; Arredondo, Mario L; Pena, Liann; Zuniga, Richard; Perez, Martin; Garcia, Clarissa

2018-02-01

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.

False Memories for Affective Information in Schizophrenia.

PubMed

Fairfield, Beth; Altamura, Mario; Padalino, Flavia A; Balzotti, Angela; Di Domenico, Alberto; Mammarella, Nicola

2016-01-01

Studies have shown a direct link between memory for emotionally salient experiences and false memories. In particular, emotionally arousing material of negative and positive valence enhanced reality monitoring compared to neutral material since emotional stimuli can be encoded with more contextual details and thereby facilitate the distinction between presented and imagined stimuli. Individuals with schizophrenia appear to be impaired in both reality monitoring and memory for emotional experiences. However, the relationship between the emotionality of the to-be-remembered material and false memory occurrence has not yet been studied. In this study, 24 patients and 24 healthy adults completed a false memory task with everyday episodes composed of 12 photographs that depicted positive, negative, or neutral outcomes. Results showed how patients with schizophrenia made a higher number of false memories than normal controls ( p  < 0.05) when remembering episodes with positive or negative outcomes. The effect of valence was apparent in the patient group. For example, it did not affect the production causal false memories ( p  > 0.05) resulting from erroneous inferences but did interact with plausible, script consistent errors in patients (i.e., neutral episodes yielded a higher degree of errors than positive and negative episodes). Affective information reduces the probability of generating causal errors in healthy adults but not in patients suggesting that emotional memory impairments may contribute to deficits in reality monitoring in schizophrenia when affective information is involved.

False Memories for Affective Information in Schizophrenia

PubMed Central

Fairfield, Beth; Altamura, Mario; Padalino, Flavia A.; Balzotti, Angela; Di Domenico, Alberto; Mammarella, Nicola

2016-01-01

Studies have shown a direct link between memory for emotionally salient experiences and false memories. In particular, emotionally arousing material of negative and positive valence enhanced reality monitoring compared to neutral material since emotional stimuli can be encoded with more contextual details and thereby facilitate the distinction between presented and imagined stimuli. Individuals with schizophrenia appear to be impaired in both reality monitoring and memory for emotional experiences. However, the relationship between the emotionality of the to-be-remembered material and false memory occurrence has not yet been studied. In this study, 24 patients and 24 healthy adults completed a false memory task with everyday episodes composed of 12 photographs that depicted positive, negative, or neutral outcomes. Results showed how patients with schizophrenia made a higher number of false memories than normal controls (p < 0.05) when remembering episodes with positive or negative outcomes. The effect of valence was apparent in the patient group. For example, it did not affect the production causal false memories (p > 0.05) resulting from erroneous inferences but did interact with plausible, script consistent errors in patients (i.e., neutral episodes yielded a higher degree of errors than positive and negative episodes). Affective information reduces the probability of generating causal errors in healthy adults but not in patients suggesting that emotional memory impairments may contribute to deficits in reality monitoring in schizophrenia when affective information is involved. PMID:27965600

Regulators of Long-Term Memory Revealed by Mushroom Body-Specific Gene Expression Profiling in Drosophila melanogaster.

PubMed

Widmer, Yves F; Bilican, Adem; Bruggmann, Rémy; Sprecher, Simon G

2018-06-20

Memory formation is achieved by genetically tightly controlled molecular pathways that result in a change of synaptic strength and synapse organization. While for short-term memory traces rapidly acting biochemical pathways are in place, the formation of long-lasting memories requires changes in the transcriptional program of a cell. Although many genes involved in learning and memory formation have been identified, little is known about the genetic mechanisms required for changing the transcriptional program during different phases of long-term memory formation. With Drosophila melanogaster as a model system we profiled transcriptomic changes in the mushroom body, a memory center in the fly brain, at distinct time intervals during appetitive olfactory long-term memory formation using the targeted DamID technique. We describe the gene expression profiles during these phases and tested 33 selected candidate genes for deficits in long-term memory formation using RNAi knockdown. We identified 10 genes that enhance or decrease memory when knocked-down in the mushroom body. For vajk-1 and hacd1 , the two strongest hits, we gained further support for their crucial role in appetitive learning and forgetting. These findings show that profiling gene expression changes in specific cell-types harboring memory traces provides a powerful entry point to identify new genes involved in learning and memory. The presented transcriptomic data may further be used as resource to study genes acting at different memory phases. Copyright © 2018, Genetics.

False memories from survival processing make better primes for problem-solving.

PubMed

Garner, Sarah R; Howe, Mark L

2014-01-01

Previous research has demonstrated that participants remember significantly more survival-related information and more information that is processed for its survival relevance. Recent research has also shown that survival materials and processing result in more false memories, ones that are adaptive inasmuch as they prime solutions to insight-based problems. Importantly, false memories for survival-related information facilitate problem solving more than false memories for other types of information. The present study explores this survival advantage using an incidental rather than intentional memory task. Here participants rated information either in the context of its importance to a survival-processing scenario or to moving to a new house. Following this, participants solved a number of compound remote associate tasks (CRATs), half of which had the solution primed by false memories that were generated during the processing task. Results showed that (a) CRATs were primed by false memories in this incidental task, with participants solving significantly more CRATs when primed than when unprimed, (b) this effect was greatest when participants rated items for survival than moving, and (c) processing items for a survival scenario improved overall problem-solving performance even when specific problems themselves were not primed. Results are discussed with regard to adaptive theories of memory.

Nogo receptor 1 regulates formation of lasting memories.

PubMed

Karlén, Alexandra; Karlsson, Tobias E; Mattsson, Anna; Lundströmer, Karin; Codeluppi, Simone; Pham, Therese M; Bäckman, Cristina M; Ogren, Sven Ove; Aberg, Elin; Hoffman, Alexander F; Sherling, Michael A; Lupica, Carl R; Hoffer, Barry J; Spenger, Christian; Josephson, Anna; Brené, Stefan; Olson, Lars

2009-12-01

Formation of lasting memories is believed to rely on structural alterations at the synaptic level. We had found that increased neuronal activity down-regulates Nogo receptor-1 (NgR1) in brain regions linked to memory formation and storage, and postulated this to be required for formation of lasting memories. We now show that mice with inducible overexpression of NgR1 in forebrain neurons have normal long-term potentiation and normal 24-h memory, but severely impaired month-long memory in both passive avoidance and swim maze tests. Blocking transgene expression normalizes these memory impairments. Nogo, Lingo-1, Troy, endogenous NgR1, and BDNF mRNA expression levels were not altered by transgene expression, suggesting that the impaired ability to form lasting memories is directly coupled to inability to down-regulate NgR1. Regulation of NgR1 may therefore serve as a key regulator of memory consolidation. Understanding the molecular underpinnings of synaptic rearrangements that carry lasting memories may facilitate development of treatments for memory dysfunction.

Nogo receptor 1 regulates formation of lasting memories

PubMed Central

Karlén, Alexandra; Karlsson, Tobias E.; Mattsson, Anna; Lundströmer, Karin; Codeluppi, Simone; Pham, Therese M.; Bäckman, Cristina M.; Ögren, Sven Ove; Åberg, Elin; Hoffman, Alexander F.; Sherling, Michael A.; Lupica, Carl R.; Hoffer, Barry J.; Spenger, Christian; Josephson, Anna; Brené, Stefan; Olson, Lars

2009-01-01

Formation of lasting memories is believed to rely on structural alterations at the synaptic level. We had found that increased neuronal activity down-regulates Nogo receptor-1 (NgR1) in brain regions linked to memory formation and storage, and postulated this to be required for formation of lasting memories. We now show that mice with inducible overexpression of NgR1 in forebrain neurons have normal long-term potentiation and normal 24-h memory, but severely impaired month-long memory in both passive avoidance and swim maze tests. Blocking transgene expression normalizes these memory impairments. Nogo, Lingo-1, Troy, endogenous NgR1, and BDNF mRNA expression levels were not altered by transgene expression, suggesting that the impaired ability to form lasting memories is directly coupled to inability to down-regulate NgR1. Regulation of NgR1 may therefore serve as a key regulator of memory consolidation. Understanding the molecular underpinnings of synaptic rearrangements that carry lasting memories may facilitate development of treatments for memory dysfunction. PMID:19915139

False memories with age: neural and cognitive underpinnings

PubMed Central

Devitt, Aleea L.; Schacter, Daniel L.

2016-01-01

As we age we become increasingly susceptible to memory distortions and inaccuracies. Over the past decade numerous neuroimaging studies have attempted to illuminate the neural underpinnings of aging and false memory. Here we review these studies, and link their findings with those concerning the cognitive properties of age-related changes in memory accuracy. Collectively this evidence points towards a prominent role for age-related declines in medial temporal and prefrontal brain areas, and corresponding impairments in associative binding and strategic monitoring. A resulting cascade of cognitive changes contributes to the heightened vulnerability to false memories with age, including reduced recollective ability, a reliance on gist information and familiarity-based monitoring mechanisms, as well as a reduced ability to inhibit irrelevant information and erroneous binding of features between memory traces. We consider both theoretical and applied implications of research on aging and false memories, as well as questions remaining to be addressed in future research. PMID:27592332

A picture is worth a thousand lies: using false photographs to create false childhood memories.

PubMed

Wade, Kimberley A; Garry, Maryanne; Read, J Don; Lindsay, D Stephen

2002-09-01

Because image-enhancing technology is readily available, people are frequently exposed to doctored images. However, in prior research on how adults can be led to report false childhood memories, subjects have typically been exposed to personalized and detailed narratives describing false events. Instead, we exposed 20 subjects to a false childhood event via a fake photograph and imagery instructions. Over three interviews, subjects thought about a photograph showing them on a hot air balloon ride and tried to recall the event byusing guided-imagery exercises. Fifty percent of the subjects created complete or partial false memories. The results bear on ways in which false memories can be created and also have practical implications for those involved in clinical and legal settings.

The roles of Eph receptors in contextual fear conditioning memory formation.

PubMed

Dines, Monica; Grinberg, Svetlana; Vassiliev, Maria; Ram, Alon; Tamir, Tal; Lamprecht, Raphael

2015-10-01

Eph receptors regulate glutamate receptors functions, neuronal morphology and synaptic plasticity, cellular events believed to be involved in memory formation. In this study we aim to explore the roles of Eph receptors in learning and memory. Toward that end, we examined the roles of EphB2 and EphA4 receptors, key regulators of synaptic functions, in fear conditioning memory formation. We show that mice lacking EphB2 (EphB2(-/-)) are impaired in short- and long-term contextual fear conditioning memory. Mice that express a carboxy-terminally truncated form of EphB2 that lacks forward signaling, instead of the full EphB2, are impaired in long-term, but not short-term, contextual fear conditioning memory. Long-term contextual fear conditioning memory is attenuated in CaMKII-cre;EphA4(lx/-) mice where EphA4 is removed from all pyramidal neurons of the forebrain. Mutant mice with targeted kinase-dead EphA4 (EphA4(KD)) exhibit intact long-term contextual fear conditioning memory showing that EphA4 kinase-mediated forward signaling is not needed for contextual fear memory formation. The ability to form long-term conditioned taste aversion (CTA) memory is not impaired in the EphB2(-/-) and CaMKII-cre;EphA4(lx/-) mice. We conclude that EphB2 forward signaling is required for long-term contextual fear conditioning memory formation. In contrast, EphB2 mediates short-term contextual fear conditioning memory formation in a forward signaling-independent manner. EphA4 mediates long-term contextual fear conditioning memory formation in a kinase-independent manner. Copyright © 2015 Elsevier Inc. All rights reserved.

The short- and long-term consequences of directed forgetting in a working memory task.

PubMed

Festini, Sara B; Reuter-Lorenz, Patricia A

2013-01-01

Directed forgetting requires the voluntary control of memory. Whereas many studies have examined directed forgetting in long-term memory (LTM), the mechanisms and effects of directed forgetting within working memory (WM) are less well understood. The current study tests how directed forgetting instructions delivered in a WM task influence veridical memory, as well as false memory, over the short and long term. In a modified item recognition task Experiment 1 tested WM only and demonstrated that directed forgetting reduces false recognition errors and semantic interference. Experiment 2 replicated these WM effects and used a surprise LTM recognition test to assess the long-term effects of directed forgetting in WM. Long-term veridical memory for to-be-remembered lists was better than memory for to-be-forgotten lists-the directed forgetting effect. Moreover, fewer false memories emerged for to-be-forgotten information than for to-be-remembered information in LTM as well. These results indicate that directed forgetting during WM reduces semantic processing of to-be-forgotten lists over the short and long term. Implications for theories of false memory and the mechanisms of directed forgetting within working memory are discussed.

Brief, pre-learning stress reduces false memory production and enhances true memory selectively in females.

PubMed

Zoladz, Phillip R; Peters, David M; Kalchik, Andrea E; Hoffman, Mackenzie M; Aufdenkampe, Rachael L; Woelke, Sarah A; Wolters, Nicholas E; Talbot, Jeffery N

2014-04-10

Some of the previous research on stress-memory interactions has suggested that stress increases the production of false memories. However, as accumulating work has shown that the effects of stress on learning and memory depend critically on the timing of the stressor, we hypothesized that brief stress administered immediately before learning would reduce, rather than increase, false memory production. In the present study, participants submerged their dominant hand in a bath of ice cold water (stress) or sat quietly (no stress) for 3 min. Then, participants completed a short-term memory task, the Deese-Roediger-McDermott paradigm, in which they were presented with 10 different lists of semantically related words (e.g., candy, sour, sugar) and, after each list, were tested for their memory of presented words (e.g., candy), non-presented unrelated "distractor" words (e.g., hat), and non-presented semantically related "critical lure" words (e.g., sweet). Stress, overall, significantly reduced the number of critical lures recalled (i.e., false memory) by participants. In addition, stress enhanced memory for the presented words (i.e., true memory) in female, but not male, participants. These findings reveal that stress does not unequivocally enhance false memory production and that the timing of the stressor is an important variable that could mediate such effects. Such results could have important implications for understanding the dependability of eyewitness accounts of events that are observed following stress. Copyright © 2014 Elsevier Inc. All rights reserved.

Epicatechin, a component of dark chocolate, enhances memory formation if applied during the memory consolidation period.

PubMed

Fernell, Maria; Swinton, Cayley; Lukowiak, Ken

2016-01-01

Epicatechin (Epi), a flavanol found in foods such as dark chocolate has previously been shown to enhance memory formation in our model system, operant conditioning of aerial respiration in Lymnaea. In those experiments snails were trained in Epi. Here we ask whether snails exposed to Epi before training, during the consolidation period immediately following training, or 1 h after training would enhance memory formation. We report here that Epi is only able to enhance memory if snails are placed in Epi-containing pond water immediately after training. That is, Epi enhances memory formation if it is applied during the memory consolidation period as well as if snails are trained in Epi-containing pond water.

Epicatechin, a component of dark chocolate, enhances memory formation if applied during the memory consolidation period

PubMed Central

Fernell, Maria; Swinton, Cayley; Lukowiak, Ken

2016-01-01

ABSTRACT Epicatechin (Epi), a flavanol found in foods such as dark chocolate has previously been shown to enhance memory formation in our model system, operant conditioning of aerial respiration in Lymnaea. In those experiments snails were trained in Epi. Here we ask whether snails exposed to Epi before training, during the consolidation period immediately following training, or 1 h after training would enhance memory formation. We report here that Epi is only able to enhance memory if snails are placed in Epi-containing pond water immediately after training. That is, Epi enhances memory formation if it is applied during the memory consolidation period as well as if snails are trained in Epi-containing pond water. PMID:27574544

The importance of material-processing interactions in inducing false memories.

PubMed

Chan, Jason C K; McDermott, Kathleen B; Watson, Jason M; Gallo, David A

2005-04-01

Deep encoding, relative to shallow encoding, has been shown to increase the probability of false memories in the Deese/Roediger-McDermott (DRM) paradigm (Thapar & McDermott, 2001; Toglia, Neuschatz, & Goodwin, 1999). In two experiments, we showed important limitations on the generalizability of this phenomenon; these limitations are clearly predicted by existing theories regarding the mechanisms underlying such false memories (e.g., Roediger, Watson, McDermott, & Gallo, 2001). Specifically, asking subjects to attend to phonological relations among lists of phonologically associated words (e.g., weep, steep, etc.) increased the likelihood of false recall (Experiment 1) and false recognition (Experiment 2) of a related, nonpresented associate (e.g., sleep), relative to a condition in which subjects attended to meaningful relations among the words. These findings occurred along with a replication of prior findings (i.e., a semantic encoding task, relative to a phonological encoding task, enhanced the likelihood of false memory arising from a list of semantically associated words), and they place important constraints on theoretical explanations of false memory.

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

PubMed

Parker, Andrew; Kember, Timothy; Dagnall, Neil

2017-07-01

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.

Haloperidol increases false recognition memory of thematically related pictures in healthy volunteers.

PubMed

Guarnieri, Regina V; Buratto, Luciano G; Gomes, Carlos F A; Ribeiro, Rafaela L; de Souza, Altay A Lino; Stein, Lilian M; Galduróz, José C; Bueno, Orlando F A

2017-01-01

Dopamine can modulate long-term episodic memory. Its potential role on the generation of false memories, however, is less well known. In a randomized, double-blind, placebo-controlled experiment, 24 young healthy volunteers ingested a 4-mg oral dose of haloperidol, a dopamine D 2 -receptor antagonist, or placebo, before taking part in a recognition memory task. Haloperidol was active during both study and test phases of the experiment. Participants in the haloperidol group produced more false recognition responses than those in the placebo group, despite similar levels of correct recognition. These findings show that dopamine blockade in healthy volunteers can specifically increase false recognition memory. Copyright © 2016 John Wiley & Sons, Ltd.

AMPK Signaling in the Dorsal Hippocampus Negatively Regulates Contextual Fear Memory Formation

PubMed Central

Han, Ying; Luo, Yixiao; Sun, Jia; Ding, Zengbo; Liu, Jianfeng; Yan, Wei; Jian, Min; Xue, Yanxue; Shi, Jie; Wang, Ji-Shi; Lu, Lin

2016-01-01

Both the formation of long-term memory (LTM) and dendritic spine growth that serves as a physical basis for the long-term storage of information require de novo protein synthesis. Memory formation also critically depends on transcription. Adenosine monophosphate-activated protein kinase (AMPK) is a transcriptional regulator that has emerged as a major energy sensor that maintains cellular energy homeostasis. However, still unknown is its role in memory formation. In the present study, we found that AMPK is primarily expressed in neurons in the hippocampus, and then we demonstrated a time-dependent decrease in AMPK activity and increase in mammalian target of rapamycin complex 1 (mTORC1) activity after contextual fear conditioning in the CA1 but not CA3 area of the dorsal hippocampus. Using pharmacological methods and adenovirus gene transfer to bidirectionally regulate AMPK activity, we found that increasing AMPK activity in the CA1 impaired the formation of long-term fear memory, and decreasing AMPK activity enhanced fear memory formation. These findings were associated with changes in the phosphorylation of AMPK and p70s6 kinase (p70s6k) and expression of BDNF and membrane GluR1 and GluR2 in the CA1. Furthermore, the prior administration of an mTORC1 inhibitor blocked the enhancing effect of AMPK inhibition on fear memory formation, suggesting that this negative regulation of contextual fear memory by AMPK in the CA1 depends on the mTORC1 signaling pathway. Finally, we found that AMPK activity regulated hippocampal spine growth associated with memory formation. In summary, our results indicate that AMPK is a key negative regulator of plasticity and fear memory formation. PMID:26647974

Event-related brain potentials that distinguish false memory for events that occurred only seconds in the past.

PubMed

Chen, Hong; Voss, Joel L; Guo, Chunyan

2012-07-30

False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM) paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP) correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs. Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task. Two categories of effects were identified that distinguished true from false short-term memory: (1) early semantic priming effects from 300 to 500 ms and (2) later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval. Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory.

Event-related brain potentials that distinguish false memory for events that occurred only seconds in the past

PubMed Central

2012-01-01

Background False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM) paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP) correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs. Methods Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task. Results Two categories of effects were identified that distinguished true from false short-term memory: (1) early semantic priming effects from 300 to 500 ms and (2) later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval. Conclusion Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory. PMID:22846189

The ERM protein Moesin is essential for neuronal morphogenesis and long-term memory in Drosophila.

PubMed

Freymuth, Patrick S; Fitzsimons, Helen L

2017-08-29

Moesin is a cytoskeletal adaptor protein that plays an important role in modification of the actin cytoskeleton. Rearrangement of the actin cytoskeleton drives both neuronal morphogenesis and the structural changes in neurons that are required for long-term memory formation. Moesin has been identified as a candidate memory gene in Drosophila, however, whether it is required for memory formation has not been evaluated. Here, we investigate the role of Moesin in neuronal morphogenesis and in short- and long-term memory formation in the courtship suppression assay, a model of associative memory. We found that both knockdown and overexpression of Moesin led to defects in axon growth and guidance as well as dendritic arborization. Moreover, reduction of Moesin expression or expression of a constitutively active phosphomimetic in the adult Drosophila brain had no effect on short term memory, but prevented long-term memory formation, an effect that was independent of its role in development. These results indicate a critical role for Moesin in both neuronal morphogenesis and long-term memory formation.

The influences of partner accuracy and partner memory ability on social false memories.

PubMed

Numbers, Katya T; Meade, Michelle L; Perga, Vladimir A

2014-11-01

In this study, we examined whether increasing the proportion of false information suggested by a confederate would influence the magnitude of socially introduced false memories in the social contagion paradigm Roediger, Meade, & Bergman (Psychonomic Bulletin & Review 8:365-371, 2001). One participant and one confederate collaboratively recalled items from previously studied household scenes. During collaboration, the confederate interjected 0 %, 33 %, 66 %, or 100 % false items. On subsequent individual-recall tests across three experiments, participants were just as likely to incorporate misleading suggestions from a partner who was mostly accurate (33 % incorrect) as they were from a partner who was not at all accurate (100 % incorrect). Even when participants witnessed firsthand that their partner had a very poor memory on a related memory task, they were still as likely to incorporate the confederate's entirely misleading suggestions on subsequent recall and recognition tests (Exp. 2). Only when participants witnessed firsthand that their partner had a very poor memory on a practice test of the experimental task itself were they able to reduce false memory, and this reduction occurred selectively on a subsequent individual recognition test (Exp. 3). These data demonstrate that participants do not always consider their partners' memory ability when working on collaborative memory tasks.

Differences in binding and monitoring mechanisms contribute to lifespan age differences in false memory.

PubMed

Fandakova, Yana; Shing, Yee Lee; Lindenberger, Ulman

2013-10-01

Based on a 2-component framework of episodic memory development across the lifespan (Shing & Lindenberger, 2011), we examined the contribution of memory-related binding and monitoring processes to false memory susceptibility in childhood and old age. We administered a repeated continuous recognition task to children (N = 20, 10-12 years), younger adults (N = 20, 20-27 years), and older adults (N = 21, 68-76 years). Participants saw the same set of unrelated word pairs in 3 consecutive runs and their task was to identify pair reoccurrences within runs. Across runs, correct detection of repeated pairs decreased in children only, whereas false recognition of lure pairs showed a greater increase in older adults than in children or younger adults. False recognition of rearranged pairs decreased across runs for all participants. This decrease was most pronounced in children, in particular for high-confidence memory errors. We conclude that memory binding mechanisms are sufficiently developed in children to facilitate memory monitoring and reduce false memory for associative information. In contrast, older adults show senescent impairments in both binding and monitoring mechanisms that both contribute to elevated illusory recollections in old age. We conclude that binding and monitoring processes during memory performance follow different developmental trajectories from childhood to old age.

The cognitive neuroscience of true and false memories.

PubMed

Johnson, Marcia K; Raye, Carol L; Mitchell, Karen J; Ankudowich, Elizabeth

2012-01-01

Of central relevance to the recovered/false memory debate is understanding the factors that cause us to believe that a mental experience is a memory of an actual past experience. According to the source monitoring framework (SMF), memories are attributions that we make about our mental experiences based on their subjective qualities, our prior knowledge and beliefs, our motives and goals, and the social context. From this perspective, we discuss cognitive behavioral studies using both objective (e.g., recognition, source memory) and subjective (e.g., ratings of memory characteristics) measures that provide much information about the encoding, revival and monitoring processes that yield both true and false memories. The chapter also considers how neuroimaging findings, especially from functional magnetic resonance imaging studies, are contributing to our understanding of the relation between memory and reality.

Visual Distinctiveness and the Development of Children's False Memories

ERIC Educational Resources Information Center

Howe, Mark L.

2008-01-01

Distinctiveness effects in children's (5-, 7-, and 11-year-olds) false memory illusions were examined using visual materials. In Experiment 1, developmental trends (increasing false memories with age) were obtained using Deese-Roediger-McDermott lists presented as words and color photographs but not line drawings. In Experiment 2, when items were…

Development of False Memories in Bilingual Children and Adults

ERIC Educational Resources Information Center

Howe, Mark L.; Gagnon, Nadine; Thouas, Lisa

2008-01-01

The effects of within- versus between-languages (English-French) study and test on rates of bilingual children's and adults' true and false memories were examined. Children aged 6 through 12 and university-aged adults participated in a standard Deese-Roediger-McDermott false memory task using free recall and recognition. Recall results showed…

Confabulation versus experimentally induced false memories in Korsakoff patients.

PubMed

Van Damme, Ilse; d'Ydewalle, Géry

2010-09-01

The present study focuses on both the clinical symptom of confabulation and experimentally induced false memories in patients suffering from Korsakoff's syndrome. Despite the vast amount of case studies of confabulating patients and studies investigating false memories in the Deese-Roediger-McDermott (DRM) paradigm, the nature of Korsakoff patients' confabulatory behaviour and its association with DRM false memories have been rarely examined. Hence, the first aim of the present study was to evaluate confabulatory responses in a large sample of chronic Korsakoff patients and matched controls by means of the Dalla Barba Confabulation Battery. Second, the association between (provoked) confabulation and the patients' DRM false recognition performance was investigated. Korsakoff patients mainly confabulated in response to questions about episodic memory and questions to which the answer was unknown. A positive association was obtained between confabulation and the tendency to accept unstudied distractor words as being old in the DRM paradigm. On the other hand, there was a negative association between confabulation and false recognition of critical lures. The latter could be attributed to the importance of strategic retrieval at delayed memory testing.

False recall and recognition of brand names increases over time.

PubMed

Sherman, Susan M

2013-01-01

Using the Deese-Roediger-McDermott (DRM) paradigm, participants are presented with lists of associated words (e.g., bed, awake, night). Subsequently, they reliably have false memories for related but nonpresented words (e.g., SLEEP). Previous research has found that false memories can be created for brand names (e.g., Morrisons, Sainsbury's, Waitrose, and TESCO). The present study investigates the effect of a week's delay on false memories for brand names. Participants were presented with lists of brand names followed by a distractor task. In two between-subjects experiments, participants completed a free recall task or a recognition task either immediately or a week later. In two within-subjects experiments, participants completed a free recall task or a recognition task both immediately and a week later. Correct recall for presented list items decreased over time, whereas false recall for nonpresented lure items increased. For recognition, raw scores revealed an increase in false memory across time reflected in an increase in Remember responses. Analysis of Pr scores revealed that false memory for lures stayed constant over a week, but with an increase in Remember responses in the between-subjects experiment and a trend in the same direction in the within-subjects experiment. Implications for theories of false memory are discussed.

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

PubMed

Scoboria, Alan; Mazzoni, Giuliana; Jarry, Josée L; Bernstein, Daniel M

2012-01-01

Suggesting false childhood events produces false autobiographical beliefs, memories and suggestion-consistent behavior. The mechanisms by which suggestion affects behavior are not understood, and whether false beliefs and memories are necessary for suggestions to impact behavior remains unexplored. We examined the relative effects of providing a personalized suggestion (suggesting that an event occurred to the person in the past), and/or a general suggestion (suggesting that an event happened to others in the past). Participants (N=122) received a personalized suggestion, a general suggestion, both or neither, about childhood illness due to spoiled peach yogurt. The personalized suggestion resulted in false beliefs, false memories, and suggestion-consistent behavioral intentions immediately after the suggestion. One week or one month later participants completed a taste test that involved eating varieties of crackers and yogurts. The personalized suggestion led to reduced consumption of only peach yogurt, and those who reported a false memory showed the most eating suppression. This effect on behavior was equally strong after one week and one month, showing a long lived influence of the personalized suggestion. The general suggestion showed no effects. Suggestions that convey personal information about a past event produce false autobiographical memories, which in turn impact behavior. Copyright © 2011 Elsevier B.V. All rights reserved.

Dnmts and Tet target memory-associated genes after appetitive olfactory training in honey bees

PubMed Central

Biergans, Stephanie D.; Giovanni Galizia, C.; Reinhard, Judith; Claudianos, Charles

2015-01-01

DNA methylation and demethylation are epigenetic mechanisms involved in memory formation. In honey bees DNA methyltransferase (Dnmt) function is necessary for long-term memory to be stimulus specific (i.e. to reduce generalization). So far, however, it remains elusive which genes are targeted and what the time-course of DNA methylation is during memory formation. Here, we analyse how DNA methylation affects memory retention, gene expression, and differential methylation in stimulus-specific olfactory long-term memory formation. Out of 30 memory-associated genes investigated here, 9 were upregulated following Dnmt inhibition in trained bees. These included Dnmt3 suggesting a negative feedback loop for DNA methylation. Within these genes also the DNA methylation pattern changed during the first 24 hours after training. Interestingly, this was accompanied by sequential activation of the DNA methylation machinery (i.e. Dnmts and Tet). In sum, memory formation involves a temporally complex epigenetic regulation of memory-associated genes that facilitates stimulus specific long-term memory in the honey bee. PMID:26531238

What Drives False Memories in Psychopathology? A Case for Associative Activation

PubMed Central

Otgaar, Henry; Muris, Peter; Howe, Mark L.; Merckelbach, Harald

2017-01-01

In clinical and court settings, it is imperative to know whether posttraumatic stress disorder (PTSD) and depression may make people susceptible to false memories. We conducted a review of the literature on false memory effects in participants with PTSD, a history of trauma, or depression. When emotional associative material was presented to these groups, their levels of false memory were raised relative to those in relevant comparison groups. This difference did not consistently emerge when neutral or nonassociative material was presented. Our conclusion is supported by a quantitative comparison of effect sizes between studies using emotional associative or neutral, nonassociative material. Our review suggests that individuals with PTSD, a history of trauma, or depression are at risk for producing false memories when they are exposed to information that is related to their knowledge base. PMID:29170722

What Drives False Memories in Psychopathology? A Case for Associative Activation.

PubMed

Otgaar, Henry; Muris, Peter; Howe, Mark L; Merckelbach, Harald

2017-11-01

In clinical and court settings, it is imperative to know whether posttraumatic stress disorder (PTSD) and depression may make people susceptible to false memories. We conducted a review of the literature on false memory effects in participants with PTSD, a history of trauma, or depression. When emotional associative material was presented to these groups, their levels of false memory were raised relative to those in relevant comparison groups. This difference did not consistently emerge when neutral or nonassociative material was presented. Our conclusion is supported by a quantitative comparison of effect sizes between studies using emotional associative or neutral, nonassociative material. Our review suggests that individuals with PTSD, a history of trauma, or depression are at risk for producing false memories when they are exposed to information that is related to their knowledge base.

Differential effects of beta-adrenergic receptor blockade in the medial prefrontal cortex during aversive and incidental taste memory formation.

PubMed

Reyes-López, J; Nuñez-Jaramillo, L; Morán-Guel, E; Miranda, M I

2010-08-11

The medial prefrontal cortex (mPFC) is a brain area crucial for memory, attention, and decision making. Specifically, the noradrenergic system in this cortex is involved in aversive learning, as well as in the retrieval of these memories. Some evidence suggests that this area has an important role during taste memory, particularly during conditioned taste aversion (CTA), a model of aversive memory. Despite some previous evidence, there is scarce information about the role of adrenergic receptors in the mPFC during formation of aversive taste memory and appetitive/incidental taste memory. The goal of this research was to evaluate the role of mPFC beta-adrenergic receptors during CTA acquisition/consolidation or CTA retrieval, as well as during incidental taste memory formation using the model of latent inhibition of CTA. The results showed that infusions in the mPFC of the beta-adrenergic antagonist propranolol before CTA acquisition impaired both short- and long-term aversive taste memory formation, and also that propranolol infusions before the memory test impaired CTA retrieval. However, propranolol infusions before pre-exposure to the taste during the latent inhibition procedure had no effect on incidental taste memory acquisition or consolidation. These data indicate that beta-adrenergic receptors in the mPFC have different functions during taste memory formation: they have an important role during aversive taste association as well as during aversive retrieval but not during incidental taste memory formation. Copyright (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

False memory and importance: can we prioritize encoding without consequence?

PubMed

Bui, Dung C; Friedman, Michael C; McDonough, Ian M; Castel, Alan D

2013-10-01

Given the large amount of information that we encounter, we often must prioritize what information we attempt to remember. Although critical for everyday functioning, relatively little research has focused on how people prioritize the encoding of information. Recent research has shown that people can and do selectively remember information assigned with higher, relative to lower, importance. However, the mechanisms underlying this prioritization process and the consequences of these processes are still not well understood. In the present study, we sought to better understand these prioritization processes and whether implementing these processes comes at the cost of memory accuracy, by increasing false memories. We used a modified form of the Deese/Roediger-McDermott (DRM) paradigm, in which participants studied DRM lists, with each list paired with low, medium, or high point values. In Experiment 1, encoding higher values led to more false memories than did encoding lower values, possibly because prioritizing information enhanced relational processing among high-value words. In Experiment 2, disrupting relational processing selectively reduced false memories for high-value words. Finally, in Experiment 3, facilitating relational processing selectively increased false memories for low-value words. These findings suggest that while prioritizing information can enhance true memory, this process concomitantly increases false memories. Furthermore, the mechanism underlying these prioritization processes depends on the ability to successfully engage in relational processing. Thus, how we prioritize the encoding of incoming information can come at a cost in terms of accurate memory.

Creating a false memory in the hippocampus.

PubMed

Ramirez, Steve; Liu, Xu; Lin, Pei-Ann; Suh, Junghyup; Pignatelli, Michele; Redondo, Roger L; Ryan, Tomás J; Tonegawa, Susumu

2013-07-26

Memories can be unreliable. We created a false memory in mice by optogenetically manipulating memory engram-bearing cells in the hippocampus. Dentate gyrus (DG) or CA1 neurons activated by exposure to a particular context were labeled with channelrhodopsin-2. These neurons were later optically reactivated during fear conditioning in a different context. The DG experimental group showed increased freezing in the original context, in which a foot shock was never delivered. The recall of this false memory was context-specific, activated similar downstream regions engaged during natural fear memory recall, and was also capable of driving an active fear response. Our data demonstrate that it is possible to generate an internally represented and behaviorally expressed fear memory via artificial means.

Stereotype threat reduces false recognition when older adults are forewarned.

PubMed

Wong, Jessica T; Gallo, David A

2016-01-01

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.

Creating Memories for False Autobiographical Events in Childhood: A Systematic Review

PubMed Central

Andrews, Bernice

2016-01-01

Summary Using a framework that distinguishes autobiographical belief, recollective experience, and confidence in memory, we review three major paradigms used to suggest false childhood events to adults: imagination inflation, false feedback and memory implantation. Imagination inflation and false feedback studies increase the belief that a suggested event occurred by a small amount such that events are still thought unlikely to have happened. In memory implantation studies, some recollective experience for the suggested events is induced on average in 47% of participants, but only in 15% are these experiences likely to be rated as full memories. We conclude that susceptibility to false memories of childhood events appears more limited than has been suggested. The data emphasise the complex judgements involved in distinguishing real from imaginary recollections and caution against accepting investigator‐based ratings as necessarily corresponding to participants' self‐reports. Recommendations are made for presenting the results of these studies in courtroom settings. © 2016 The Authors Applied Cognitive Psychology Published by John Wiley & Sons Ltd. PMID:28163368

Creating Non-Believed Memories for Recent Autobiographical Events

PubMed Central

Clark, Andrew; Nash, Robert A.; Fincham, Gabrielle; Mazzoni, Giuliana

2012-01-01

A recent study showed that many people spontaneously report vivid memories of events that they do not believe to have occurred [1]. In the present experiment we tested for the first time whether, after powerful false memories have been created, debriefing might leave behind nonbelieved memories for the fake events. In Session 1 participants imitated simple actions, and in Session 2 they saw doctored video-recordings containing clips that falsely suggested they had performed additional (fake) actions. As in earlier studies, this procedure created powerful false memories. In Session 3, participants were debriefed and told that specific actions in the video were not truly performed. Beliefs and memories for all critical actions were tested before and after the debriefing. Results showed that debriefing undermined participants' beliefs in fake actions, but left behind residual memory-like content. These results indicate that debriefing can leave behind vivid false memories which are no longer believed, and thus we demonstrate for the first time that the memory of an event can be experimentally dissociated from the belief in the event's occurrence. These results also confirm that belief in and memory for an event can be independently-occurring constructs. PMID:22427927

[Effects of false memories on the Concealed Information Test].

PubMed

Zaitsu, Wataru

2012-10-01

The effects of false memories on polygraph examinations with the Concealed Information Test (CIT) were investigated by using the Deese-Roediger-McDermott (DRM) paradigm, which allows participants to evoke false memories. Physiological responses to questions consisting of learned, lure, and unlearned items were measured and recorded. The results indicated that responses to lure questions showed critical responses to questions about learned items. These responses included repression of respiration, an increase in electrodermal activity, and a drop in heart rate. These results suggest that critical response patterns are generated in the peripheral nervous system by true and false memories.

Study modality and false recall.

PubMed

Smith, Rebekah E; Engle, Randall W

2011-01-01

False memories occur when individuals mistakenly report an event as having taken place when that event did not in fact occur. The DRM (Deese, 1959; Roediger & McDermott, 1995) paradigm provides an effective technique for creating and investigating false memories. In this paradigm participants study a list of words (e.g., SOUR, CANDY,…) that are highly associated to a non-presented critical item (e.g., SWEET). The study phase is followed by a test of memory for the study list words. Researchers typically find very high levels of false recall of the critical non-presented item. However, the likelihood of falsely remembering the non-presented critical items can be reduced by presenting studied associates visually rather than auditorally (e.g., Smith & Hunt, 1998). This is referred to as the modality effect in false memory. The current study investigated the role of resource availability in the expression of this modality effect in false recall. In Experiment 1 false recall was reduced in the visual study presentation condition relative to the auditory condition for participants with higher working memory capacity, but not for participants with lower working memory capacity. In Experiment 2 the effect of study modality on false recall was eliminated by the addition of a divided attention task at encoding. Both studies support the proposal that resource availability plays a role in the expression of the modality effect in the DRM paradigm (Smith, Lozito, & Bayen, 2005).

Misremembering what you see or hear: Dissociable effects of modality on short- and long-term false recognition.

PubMed

Olszewska, Justyna M; Reuter-Lorenz, Patricia A; Munier, Emily; Bendler, Sara A

2015-09-01

False working memories readily emerge using a visual item-recognition variant of the converging associates task. Two experiments, manipulating study and test modality, extended prior working memory results by demonstrating a reliable false recognition effect (more false alarms to associatively related lures than to unrelated lures) within seconds of encoding in either the visual or auditory modality. However, false memories were nearly twice as frequent when study lists were seen than when they were heard, regardless of test modality, although study-test modality mismatch was generally disadvantageous (consistent with encoding specificity). A final experiment that varied study-test modality using a hybrid short- and long-term memory test (Flegal, Atkins & Reuter-Lorenz, 2010) replicated the auditory advantage in the short term but revealed a reversal in the long term: The false memory effect was greater in the auditory study-test condition than in the visual study-test condition. Thus, the same encoding conditions gave rise to an opposite modality advantage depending on whether recognition was tested under short-term or long-term memory conditions. Although demonstrating continuity in associative processing across delay, the results indicate that delay condition affects the availability of modality-dependent features of the memory trace and, thus, distinctiveness, leading to dissociable patterns of short- and long-term memory performance. (c) 2015 APA, all rights reserved).

Eighteen-month-olds' memory interference and distraction in a modified A-not-B task is not associated with their anticipatory looking in a false-belief task.

PubMed

Zmyj, Norbert; Prinz, Wolfgang; Daum, Moritz M

2015-01-01

Infants' performance in non-verbal false-belief tasks is often interpreted as if they have understood false beliefs. This view has been questioned by a recent account that explains infants' performance in non-verbal false-belief tasks as the result of susceptibility to memory interference and distraction. We tested this alternative account by investigating the relationship between infants' false-belief understanding, susceptibility to memory interference and distraction, and general cognitive development in 18-month-old infants (N = 22). False-belief understanding was tested in an anticipatory looking paradigm of a standard false-belief task. Susceptibility to memory interference and distraction was tested in a modified A-not-B task. Cognitive development was measured via the Mental Scale of the Bayley Scales of Infant Development. We did not find any relationship between infants' performance in the false-belief task and the A-not-B task, even after controlling for cognitive development. This study shows that there is no ubiquitous relation between susceptibility to memory interference and distraction and performance in a false-belief task in infancy.

Eighteen-month-olds’ memory interference and distraction in a modified A-not-B task is not associated with their anticipatory looking in a false-belief task

PubMed Central

Zmyj, Norbert; Prinz, Wolfgang; Daum, Moritz M.

2015-01-01

Infants’ performance in non-verbal false-belief tasks is often interpreted as if they have understood false beliefs. This view has been questioned by a recent account that explains infants’ performance in non-verbal false-belief tasks as the result of susceptibility to memory interference and distraction. We tested this alternative account by investigating the relationship between infants’ false-belief understanding, susceptibility to memory interference and distraction, and general cognitive development in 18-month-old infants (N = 22). False-belief understanding was tested in an anticipatory looking paradigm of a standard false-belief task. Susceptibility to memory interference and distraction was tested in a modified A-not-B task. Cognitive development was measured via the Mental Scale of the Bayley Scales of Infant Development. We did not find any relationship between infants’ performance in the false-belief task and the A-not-B task, even after controlling for cognitive development. This study shows that there is no ubiquitous relation between susceptibility to memory interference and distraction and performance in a false-belief task in infancy. PMID:26157409

Sleep Reduces False Memory in Healthy Older Adults

PubMed Central

Lo, June C.; Sim, Sam K. Y.; Chee, Michael W. L.

2014-01-01

Study Objectives: To investigate the effects of post-learning sleep and sleep architecture on false memory in healthy older adults. Design: Balanced, crossover design. False memory was induced using the Deese-Roediger-McDermott (DRM) paradigm and assessed following nocturnal sleep and following a period of daytime wakefulness. Post-learning sleep structure was evaluated using polysomnography (PSG). Setting: Sleep research laboratory. Participants: Fourteen healthy older adults from the Singapore-Longitudinal Aging Brain Study (mean age ± standard deviation = 66.6 ± 4.1 y; 7 males). Measurements and Results: At encoding, participants studied lists of words that were semantically related to non-presented critical lures. At retrieval, they made “remember”/“know” and “new” judgments. Compared to wakefulness, post-learning sleep was associated with reduced “remember” responses, but not “know” responses to critical lures. In contrast, there were no significant differences in the veridical recognition of studied words, false recognition of unrelated distractors, discriminability, or response bias between the sleep and the wake conditions. More post-learning slow wave sleep was associated with greater reduction in false memory. Conclusions: In healthy older adults, sleep facilitates the reduction in false memory without affecting veridical memory. This benefit correlates with the amount of slow wave sleep in the post-learning sleep episode. Citation: Lo JC; Sim SK; Chee MW. Sleep reduces false memory in healthy older adults. SLEEP 2014;37(4):665-671. PMID:24744453

Dynamics of Hippocampal Protein Expression During Long-term Spatial Memory Formation*

PubMed Central

Borovok, Natalia; Nesher, Elimelech; Levin, Yishai; Reichenstein, Michal; Pinhasov, Albert

2016-01-01

Spatial memory depends on the hippocampus, which is particularly vulnerable to aging. This vulnerability has implications for the impairment of navigation capacities in older people, who may show a marked drop in performance of spatial tasks with advancing age. Contemporary understanding of long-term memory formation relies on molecular mechanisms underlying long-term synaptic plasticity. With memory acquisition, activity-dependent changes occurring in synapses initiate multiple signal transduction pathways enhancing protein turnover. This enhancement facilitates de novo synthesis of plasticity related proteins, crucial factors for establishing persistent long-term synaptic plasticity and forming memory engrams. Extensive studies have been performed to elucidate molecular mechanisms of memory traces formation; however, the identity of plasticity related proteins is still evasive. In this study, we investigated protein turnover in mouse hippocampus during long-term spatial memory formation using the reference memory version of radial arm maze (RAM) paradigm. We identified 1592 proteins, which exhibited a complex picture of expression changes during spatial memory formation. Variable linear decomposition reduced significantly data dimensionality and enriched three principal factors responsible for variance of memory-related protein levels at (1) the initial phase of memory acquisition (165 proteins), (2) during the steep learning improvement (148 proteins), and (3) the final phase of the learning curve (123 proteins). Gene ontology and signaling pathways analysis revealed a clear correlation between memory improvement and learning phase-curbed expression profiles of proteins belonging to specific functional categories. We found differential enrichment of (1) neurotrophic factors signaling pathways, proteins regulating synaptic transmission, and actin microfilament during the first day of the learning curve; (2) transcription and translation machinery, protein trafficking, enhancement of metabolic activity, and Wnt signaling pathway during the steep phase of memory formation; and (3) cytoskeleton organization proteins. Taken together, this study clearly demonstrates dynamic assembly and disassembly of protein-protein interaction networks depending on the stage of memory formation engrams. PMID:26598641

A Role of Protein Degradation in Memory Consolidation after Initial Learning and Extinction Learning in the Honeybee ("Apis mellifera")

ERIC Educational Resources Information Center

Felsenberg, Johannes; Dombrowski, Vincent; Eisenhardt, Dorothea

2012-01-01

Protein degradation is known to affect memory formation after extinction learning. We demonstrate here that an inhibitor of protein degradation, MG132, interferes with memory formation after extinction learning in a classical appetitive conditioning paradigm. In addition, we find an enhancement of memory formation when the same inhibitor is…

Oscillatory theta activity during memory formation and its impact on overnight consolidation: a missing link?

PubMed

Heib, Dominik P J; Hoedlmoser, Kerstin; Anderer, Peter; Gruber, Georg; Zeitlhofer, Josef; Schabus, Manuel

2015-08-01

Sleep has been shown to promote memory consolidation driven by certain oscillatory patterns, such as sleep spindles. However, sleep does not consolidate all newly encoded information uniformly but rather "selects" certain memories for consolidation. It is assumed that such selection depends on salience tags attached to the new memories before sleep. However, little is known about the underlying neuronal processes reflecting presleep memory tagging. The current study sought to address the question of whether event-related changes in spectral theta power (theta ERSP) during presleep memory formation could reflect memory tagging that influences subsequent consolidation during sleep. Twenty-four participants memorized 160 word pairs before sleep; in a separate laboratory visit, they performed a nonlearning control task. Memory performance was tested twice, directly before and after 8 hr of sleep. Results indicate that participants who improved their memory performance overnight displayed stronger theta ERSP during the memory task in comparison with the control task. They also displayed stronger memory task-related increases in fast sleep spindle activity. Furthermore, presleep theta activity was directly linked to fast sleep spindle activity, indicating that processes during memory formation might indeed reflect memory tagging that influences subsequent consolidation during sleep. Interestingly, our results further indicate that the suggested relation between sleep spindles and overnight performance change is not as direct as once believed. Rather, it appears to be mediated by processes beginning during presleep memory formation. We conclude that theta ERSP during presleep memory formation reflects cortico-hippocampal interactions that lead to a better long-term accessibility by tagging memories for sleep spindle-related reprocessing.

Using warnings to reduce categorical false memories in younger and older adults.

PubMed

Carmichael, Anna M; Gutchess, Angela H

2016-07-01

Warnings about memory errors can reduce their incidence, although past work has largely focused on associative memory errors. The current study sought to explore whether warnings could be tailored to specifically reduce false recall of categorical information in both younger and older populations. Before encoding word pairs designed to induce categorical false memories, half of the younger and older participants were warned to avoid committing these types of memory errors. Older adults who received a warning committed fewer categorical memory errors, as well as other types of semantic memory errors, than those who did not receive a warning. In contrast, young adults' memory errors did not differ for the warning versus no-warning groups. Our findings provide evidence for the effectiveness of warnings at reducing categorical memory errors in older adults, perhaps by supporting source monitoring, reduction in reliance on gist traces, or through effective metacognitive strategies.

Hippocampal and ventral medial prefrontal activation during retrieval-mediated learning supports novel inference.

PubMed

Zeithamova, Dagmar; Dominick, April L; Preston, Alison R

2012-07-12

Memory enables flexible use of past experience to inform new behaviors. Although leading theories hypothesize that this fundamental flexibility results from the formation of integrated memory networks relating multiple experiences, the neural mechanisms that support memory integration are not well understood. Here, we demonstrate that retrieval-mediated learning, whereby prior event details are reinstated during encoding of related experiences, supports participants' ability to infer relationships between distinct events that share content. Furthermore, we show that activation changes in a functionally coupled hippocampal and ventral medial prefrontal cortical circuit track the formation of integrated memories and successful inferential memory performance. These findings characterize the respective roles of these regions in retrieval-mediated learning processes that support relational memory network formation and inferential memory in the human brain. More broadly, these data reveal fundamental mechanisms through which memory representations are constructed into prospectively useful formats. Copyright © 2012 Elsevier Inc. All rights reserved.

Hippocampal and ventral medial prefrontal activation during retrieval-mediated learning supports novel inference

PubMed Central

Zeithamova, Dagmar; Dominick, April L.; Preston, Alison R.

2012-01-01

SUMMARY Memory enables flexible use of past experience to inform new behaviors. Though leading theories hypothesize that this fundamental flexibility results from the formation of integrated memory networks relating multiple experiences, the neural mechanisms that support memory integration are not well understood. Here, we demonstrate that retrieval-mediated learning, whereby prior event details are reinstated during encoding of related experiences, supports participants’ ability to infer relationships between distinct events that share content. Furthermore, we show that activation changes in a functionally coupled hippocampal and ventral medial prefrontal cortical circuit track the formation of integrated memories and successful inferential memory performance. These findings characterize the respective roles of these regions in retrieval-mediated learning processes that support relational memory network formation and inferential memory in the human brain. More broadly, these data reveal fundamental mechanisms through which memory representations are constructed into prospectively useful formats. PMID:22794270

Effects of Aging and Education on False Memory

ERIC Educational Resources Information Center

Lee, Yuh-Shiow; Lee, Chia-Lin; Yang, Hua-Te

2012-01-01

This study examined the effects of aging and education on participants' false memory for words that were not presented. Three age groups of participants with either a high or low education level were asked to study lists of semantically related words. Both age and education were found to affect veridical and false memory, as indicated in the…

Hemispheric Asymmetries in Discourse Processing: Evidence from False Memories for Lists and Texts

ERIC Educational Resources Information Center

Ben-Artzi, Elisheva; Faust, Miriam; Moeller, Edna

2009-01-01

Previous research suggests that the right hemisphere (RH) may contribute uniquely to discourse and text processing by activating and maintaining a wide range of meanings, including more distantly related meanings. The present study used the word-lists false memory paradigm [Roediger, H. L., III, & McDermott, K. B. (1995). "Creating false memories:…

Source Monitoring and False Memories in Children: Relation to Certainty and Executive Functioning.

ERIC Educational Resources Information Center

Ruffman, Ted; Rustin, Charlotte; Garnham, Wendy; Parkin, Alan J.

2001-01-01

Examined source monitoring and false memories in 6-, 8-, and 10-year-olds related to their memory of information presented by videotape and/or audiotape. Found that certainty rating revealed deficits in children's understanding of when they had erred on source questions and when they had made false alarms. Inhibitory ability accounted for unique…

Amnesiacs might get the gist: reduced false recognition in amnesia may be the result of impaired item-specific memory.

PubMed

Nissan, Jack; Abrahams, Sharon; Sala, Sergio Della

2013-01-01

It is a common finding in tests of false recognition that amnesic patients recognize fewer related lures than healthy controls, and this has led to assumptions that gist memory is damaged in these patients (Schacter, Verfaellie, & Anes, 1997, Neuropsychology, 11; Schacter, Verfaellie, Anes, & Racine, 1998, Journal of Cognitive Neuroscience, 10; Schacter, Verfaellie, & Pradere, 1996, Journal of Memory and Language, 35). However, clinical observations find that amnesic patients typically hold meaningful conversations and make relevant remarks, and there is some experimental evidence highlighting preserved immediate recall of prose (Baddeley & Wilson, 2002, Neuropsychologia, 40; Gooding, Isaac, & Mayes, 2005, Neuropsychologia, 43; Rosenbaum, Gilboa, Levine, Winocur, & Moscovitch, 2009, Neuropsychologia, 47), which suggests that amnesiacs can get the gist. The present experiment used false recognition paradigms to assess whether the reduced rate of false recognition found in amnesic patients may be a consequence of their impaired item-specific memory. It examined the effect of increasing the item-specific memory of amnesic patient DA by bringing her to criterion on relevant study-lists and compared her performance on a false recognition paradigm with a group of 32 healthy young adults. Results indicated that when DA's item-specific memory was increased she was more able to gist and her performance was no different to the healthy young adults. Previous assumptions that gist memory is necessarily damaged in amnesia might therefore be revisited, since the reduced rate of false recognition could be caused by impaired item-specific memory. The experiment also highlights a positive relationship between item-specific and gist memory which has not previously been accounted for in false-recognition experiments.

Source monitoring and false memories in children: relation to certainty and executive functioning.

PubMed

Ruffman, T; Rustin, C; Garnham, W; Parkin, A J

2001-10-01

We presented children aged 6, 8, and 10 years with a video and then an audio tape about a dog named Mick. Some information was repeated in the two sources and some was unique to one source. We examined: (a) children's hit rate for remembering whether events occurred and their tendency to make false alarms, (b) their memory for the context in which events occurred (source monitoring), (c) their certainty about hits, false alarms, and source, and (d) whether working memory and inhibition were related to hits, false alarms, and source monitoring. The certainty ratings revealed deficits in children's understanding of when they had erred on source questions and of when they had made false alarms. In addition, inhibitory ability accounted for unique variance in the ability to avoid false alarms and in some kinds of source monitoring but not hits. In contrast, working memory tended to correlate with all forms of memory including hits. Copyright 2001 Academic Press.

Neural Global Pattern Similarity Underlies True and False Memories.

PubMed

Ye, Zhifang; Zhu, Bi; Zhuang, Liping; Lu, Zhonglin; Chen, Chuansheng; Xue, Gui

2016-06-22

The neural processes giving rise to human memory strength signals remain poorly understood. Inspired by formal computational models that posit a central role of global matching in memory strength, we tested a novel hypothesis that the strengths of both true and false memories arise from the global similarity of an item's neural activation pattern during retrieval to that of all the studied items during encoding (i.e., the encoding-retrieval neural global pattern similarity [ER-nGPS]). We revealed multiple ER-nGPS signals that carried distinct information and contributed differentially to true and false memories: Whereas the ER-nGPS in the parietal regions reflected semantic similarity and was scaled with the recognition strengths of both true and false memories, ER-nGPS in the visual cortex contributed solely to true memory. Moreover, ER-nGPS differences between the parietal and visual cortices were correlated with frontal monitoring processes. By combining computational and neuroimaging approaches, our results advance a mechanistic understanding of memory strength in recognition. What neural processes give rise to memory strength signals, and lead to our conscious feelings of familiarity? Using fMRI, we found that the memory strength of a given item depends not only on how it was encoded during learning, but also on the similarity of its neural representation with other studied items. The global neural matching signal, mainly in the parietal lobule, could account for the memory strengths of both studied and unstudied items. Interestingly, a different global matching signal, originated from the visual cortex, could distinguish true from false memories. The findings reveal multiple neural mechanisms underlying the memory strengths of events registered in the brain. Copyright © 2016 the authors 0270-6474/16/366792-11$15.00/0.

Two Components of Aversive Memory in Drosophila, Anesthesia-Sensitive and Anesthesia-Resistant Memory, Require Distinct Domains Within the Rgk1 Small GTPase.

PubMed

Murakami, Satoshi; Minami-Ohtsubo, Maki; Nakato, Ryuichiro; Shirahige, Katsuhiko; Tabata, Tetsuya

2017-05-31

Multiple components have been identified that exhibit different stabilities for aversive olfactory memory in Drosophila These components have been defined by behavioral and genetic studies and genes specifically required for a specific component have also been identified. Intermediate-term memory generated after single cycle conditioning is divided into anesthesia-sensitive memory (ASM) and anesthesia-resistant memory (ARM), with the latter being more stable. We determined that the ASM and ARM pathways converged on the Rgk1 small GTPase and that the N-terminal domain-deleted Rgk1 was sufficient for ASM formation, whereas the full-length form was required for ARM formation. Rgk1 is specifically accumulated at the synaptic site of the Kenyon cells (KCs), the intrinsic neurons of the mushroom bodies, which play a pivotal role in olfactory memory formation. A higher than normal Rgk1 level enhanced memory retention, which is consistent with the result that Rgk1 suppressed Rac-dependent memory decay; these findings suggest that rgk1 bolsters ASM via the suppression of forgetting. We propose that Rgk1 plays a pivotal role in the regulation of memory stabilization by serving as a molecular node that resides at KC synapses, where the ASM and ARM pathway may interact. SIGNIFICANCE STATEMENT Memory consists of multiple components. Drosophila olfactory memory serves as a fundamental model with which to investigate the mechanisms that underlie memory formation and has provided genetic and molecular means to identify the components of memory, namely short-term, intermediate-term, and long-term memory, depending on how long the memory lasts. Intermediate memory is further divided into anesthesia-sensitive memory (ASM) and anesthesia-resistant memory (ARM), with the latter being more stable. We have identified a small GTPase in Drosophila , Rgk1, which plays a pivotal role in the regulation of olfactory memory stability. Rgk1 is required for both ASM and ARM. Moreover, N-terminal domain-deleted Rgk1 was sufficient for ASM formation, whereas the full-length form was required for ARM formation. Copyright © 2017 the authors 0270-6474/17/375496-•$15.00/0.

False memories with age: Neural and cognitive underpinnings.

PubMed

Devitt, Aleea L; Schacter, Daniel L

2016-10-01

As we age we become increasingly susceptible to memory distortions and inaccuracies. Over the past decade numerous neuroimaging studies have attempted to illuminate the neural underpinnings of aging and false memory. Here we review these studies, and link their findings with those concerning the cognitive properties of age-related changes in memory accuracy. Collectively this evidence points towards a prominent role for age-related declines in medial temporal and prefrontal brain areas, and corresponding impairments in associative binding and strategic monitoring. A resulting cascade of cognitive changes contributes to the heightened vulnerability to false memories with age, including reduced recollective ability, a reliance on gist information and familiarity-based monitoring mechanisms, as well as a reduced ability to inhibit irrelevant information and erroneous binding of features between memory traces. We consider both theoretical and applied implications of research on aging and false memories, as well as questions remaining to be addressed in future research. Copyright © 2016 Elsevier Ltd. All rights reserved.

What is the connection between true and false memories? The differential roles of interitem associations in recall and recognition.

PubMed

McEvoy, C L; Nelson, D L; Komatsu, T

1999-09-01

Veridical memory for presented list words and false memory for nonpresented but related items were tested using the Deese/Roediger and McDermott paradigm. The strength and density of preexisting connections among the list words, and from the list words to the critical items, were manipulated. The likelihood of producing false memories in free recall varied with the strength of connections from the list words to the critical items but was inversely related to the density of the interconnections among the list words. In contrast, veridical recall of list words was positively related to the density of the interconnections. A final recognition test showed that both false and veridical memories were more likely when the list words were more densely interconnected. The results are discussed in terms of an associative model of memory, Processing Implicit and Explicit Representations (PIER 2) that describes the influence of implicitly activated preexisting information on memory performance.

The Role of Ephs and Ephrins in Memory Formation

PubMed Central

Dines, Monica

2016-01-01

The ability to efficiently store memories in the brain is a fundamental process and its impairment is associated with multiple human mental disorders. Evidence indicates that long-term memory formation involves alterations of synaptic efficacy produced by modifications in neural transmission and morphology. The Eph receptors and their cognate ephrin ligands have been shown to be involved in these key neuronal processes by regulating events such as presynaptic transmitter release, postsynaptic glutamate receptor conductance and trafficking, synaptic glutamate reuptake, and dendritic spine morphogenesis. Recent findings show that Ephs and ephrins are needed for memory formation in different organisms. These proteins participate in the formation of various types of memories that are subserved by different neurons and brain regions. Ephs and ephrins are involved in brain disorders and diseases with memory impairment symptoms, including Alzheimer’s disease and anxiety. Drugs that agonize or antagonize Ephs/ephrins signaling have been developed and could serve as therapeutic agents to treat such diseases. Ephs and ephrins may therefore induce cellular alterations mandatory for memory formation and serve as a target for pharmacological intervention for treatment of memory-related brain diseases. PMID:26371183

Arp2/3 and VASP Are Essential for Fear Memory Formation in Lateral Amygdala.

PubMed

Basu, Sreetama; Kustanovich, Irina; Lamprecht, Raphael

2016-01-01

The actin cytoskeleton is involved in key neuronal functions such as synaptic transmission and morphogenesis. However, the roles and regulation of actin cytoskeleton in memory formation remain to be clarified. In this study, we unveil the mechanism whereby actin cytoskeleton is regulated to form memory by exploring the roles of the major actin-regulatory proteins Arp2/3, VASP, and formins in long-term memory formation. Inhibition of Arp2/3, involved in actin filament branching and neuronal morphogenesis, in lateral amygdala (LA) with the specific inhibitor CK-666 during fear conditioning impaired long-term, but not short-term, fear memory. The inactive isomer CK-689 had no effect on memory formation. We observed that Arp2/3 is colocalized with the actin-regulatory protein profilin in LA neurons of fear-conditioned rats. VASP binding to profilin is needed for profilin-mediated stabilization of actin cytoskeleton and dendritic spine morphology. Microinjection of poly-proline peptide [G(GP 5 ) 3 ] into LA, to interfere with VASP binding to profilin, impaired long-term but not short-term fear memory formation. Control peptide [G(GA 5 ) 3 ] had no effect. Inhibiting formins, which regulate linear actin elongation, in LA during fear conditioning by microinjecting the formin-specific inhibitor SMIFH2 into LA had no effect on long-term fear memory formation. We conclude that Arp2/3 and VASP, through the profilin binding site, are essential for the formation of long-term fear memory in LA and propose a model whereby these proteins subserve cellular events, leading to memory consolidation.

False memory in aging: effects of emotional valence on word recognition accuracy.

PubMed

Piguet, Olivier; Connally, Emily; Krendl, Anne C; Huot, Jessica R; Corkin, Suzanne

2008-06-01

Memory is susceptible to distortions. Valence and increasing age are variables known to affect memory accuracy and may increase false alarm production. Interaction between these variables and their impact on false memory was investigated in 36 young (18-28 years) and 36 older (61-83 years) healthy adults. At study, participants viewed lists of neutral words orthographically related to negative, neutral, or positive critical lures (not presented). Memory for these words was subsequently tested with a remember-know procedure. At test, items included the words seen at study and their associated critical lures, as well as sets of orthographically related neutral words not seen at study and their associated unstudied lures. Positive valence was shown to have two opposite effects on older adults' discrimination of the lures: It improved correct rejection of unstudied lures but increased false memory for critical lures (i.e., lures associated with words studied previously). Thus, increased salience triggered by positive valence may disrupt memory accuracy in older adults when discriminating among similar events. These findings likely reflect a source memory deficit due to decreased efficiency in cognitive control processes with aging.

The epigenetic basis of memory formation and storage.

PubMed

Jarome, Timothy J; Thomas, Jasmyne S; Lubin, Farah D

2014-01-01

The formation of long-term memory requires a series of cellular and molecular changes that involve transcriptional regulation of gene expression. While these changes in gene transcription were initially thought to be largely regulated by the activation of transcription factors by intracellular signaling molecules, epigenetic mechanisms have emerged as an important regulator of transcriptional processes across multiple brain regions to form a memory circuit for a learned event or experience. Due to their self-perpetuating nature and ability to bidirectionally control gene expression, these epigenetic mechanisms have the potential to not only regulate initial memory formation but also modify and update memory over time. This chapter focuses on the established, but poorly understood, role for epigenetic mechanisms such as posttranslational modifications of histone proteins and DNA methylation at the different stages of memory storage. Additionally, this chapter emphasizes how these mechanisms interact to control the ideal epigenetic environment for memory formation and modification in neurons. The reader will gain insights into the limitations in our current understanding of epigenetic regulation of memory storage, especially in terms of their cell-type specificity and the lack of understanding in the interactions of various epigenetic modifiers to one another to impact gene expression changes during memory formation.

Emotionally Negative Pictures Enhance Gist Memory

PubMed Central

Bookbinder, S. H.; Brainerd, C. J.

2016-01-01

In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are due to valence and which are due to arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively-valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling revealed that negative valence (a) reduced erroneous suppression of true memories and (b) increased the familiarity of the semantic content of both true and false memories. Overall, negative valence impaired the verbatim side of episodic memory but enhanced the gist side, and these effects persisted even after a week-long delay. PMID:27454002

Eliminating age differences in children's and adults' suggestibility and memory conformity effects.

PubMed

Otgaar, Henry; Howe, Mark L; Brackmann, Nathalie; van Helvoort, Daniël H J

2017-05-01

We examined whether typical developmental trends in suggestion-induced false memories (i.e., age-related decrease) could be changed. Using theoretical principles from the spontaneous false memory field, we adapted 2 often-used false memory procedures: misinformation (Experiment 1) and memory conformity (Experiment 2). In Experiment 1, 7- to 9-year-old children (n = 33) and adults (n = 39) received stories containing associatively related details. They then listened to misinformation in the form of short narratives preserving the meaning of the story. Children and adults were equally susceptible to the misinformation effect. In Experiment 2, younger (7- to 8-year-olds, n = 30) and older (11- to 12-year-olds, n = 30) children and adults (n = 30) viewed pictures containing associatively related details. They viewed these pictures in pairs. Although the pictures differed, participants believed they had viewed the same pictures. Participants had to report what they could recollect during collaborative and individual recall tests. Children and adults were equally susceptible to memory conformity effects. When correcting for response bias, adults' false memory scores were even higher than children's. Our results show that age trends in suggestion-induced false memories are not developmentally invariant. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Effects of depressive disorder on false memory for emotional information.

PubMed

Yeh, Zai-Ting; Hua, Mau-Sun

2009-01-01

This study explored with a false memory paradigm whether (1) depressed patients revealed more false memories and (2) whether more negative false than positive false recognition existed in subjects with depressive disorders. Thirty-two patients suffering from a major depressive episode (DSM-IV criteria), and 30 age- and education-matched normal control subjects participated in this study. After the presentation of a list of positive, negative, and neutral association items in the learning phase, subjects were asked to give a yes/no response in the recognition phase. They were also asked to rate 81 recognition items with emotional valence scores. The results revealed more negative false memories in the clinical depression group than in the normal control group; however, we did not find more negative false memories than positive ones in patients. When compared with the normal group, a more conservative response criterion for positive items was evident in patient groups. It was also found that when compared with the normal group, the subjects in the depression group perceived the positive items as less positive. On the basis of present results, it is suggested that depressed subjects judged the emotional information with criteria different from normal individuals, and patients' emotional memory intensity is attenuated by their mood.

Age Differences in the Rejection of False Memories: The Effects of Giving Warning Instructions and Slowing the Presentation Rate

ERIC Educational Resources Information Center

Carneiro, Paula; Fernandez, Angel

2010-01-01

Two experiments were conducted to examine whether children of different ages differ in their ability to reject associative false memories with the Deese-Roediger-McDermott (DRM) paradigm. Two different types of manipulations that are thought to facilitate false memory rejection in adults--slowing the presentation rate and issuing explicit…

What Is False Memory Development the Development of? Comment on Brainerd, Reyna, and Ceci (2008)

ERIC Educational Resources Information Center

Howe, Mark L.

2008-01-01

In this commentary, assumptions about the nature and development of children's false memories as described in a recent article by C. J. Brainerd, V. F. Reyna, and S. J. Ceci (2008) are reviewed. Specifically, questions are raised about what drives the development of false memories in fuzzy-trace theory (FTT). Recent studies that challenge a core…

Not strange but not true: self-reported interest in a topic increases false memory.

PubMed

O'Connell, Anthony; Greene, Ciara M

2017-09-01

People are more likely to recall both true and false information that is consistent with their pre-existing stereotypes, schemata and desires. In addition, experts in a particular field are more likely to experience false memory in relation to their area of expertise. Here, we investigate whether level of interest, as distinct from level of knowledge, and in the absence of self-professed expertise, is associated with increased false memory. 489 participants were asked to rank 7 topics from most to least interesting. They were then asked if they remembered the events described in four news items related to the topic they selected as the most interesting and four items related to the topic selected as least interesting. In each case, three of the events depicted had really happened and one was fictional. A high level of interest in a topic increased true memories for the topic and doubled the frequency of false memories, even after controlling for level of knowledge. We interpret the results in the context of the source-monitoring framework and suggest that false memories arise as a result of interference from existing information stored in domain-related schemata.

Sleep reduces false memory in healthy older adults.

PubMed

Lo, June C; Sim, Sam K Y; Chee, Michael W L

2014-04-01

To investigate the effects of post-learning sleep and sleep architecture on false memory in healthy older adults. Balanced, crossover design. False memory was induced using the Deese-Roediger-McDermott (DRM) paradigm and assessed following nocturnal sleep and following a period of daytime wakefulness. Post-learning sleep structure was evaluated using polysomnography (PSG). Sleep research laboratory. Fourteen healthy older adults from the Singapore-Longitudinal Aging Brain Study (mean age ± standard deviation = 66.6 ± 4.1 y; 7 males). At encoding, participants studied lists of words that were semantically related to non-presented critical lures. At retrieval, they made "remember"/"know" and "new" judgments. Compared to wakefulness, post-learning sleep was associated with reduced "remember" responses, but not "know" responses to critical lures. In contrast, there were no significant differences in the veridical recognition of studied words, false recognition of unrelated distractors, discriminability, or response bias between the sleep and the wake conditions. More post-learning slow wave sleep was associated with greater reduction in false memory. In healthy older adults, sleep facilitates the reduction in false memory without affecting veridical memory. This benefit correlates with the amount of slow wave sleep in the post-learning sleep episode.

When plausibility manipulations work: an examination of their role in the development of false beliefs and memories.

PubMed

Bays, Rebecca B; Zabrucky, Karen M; Gagne, Phill

2012-01-01

In the current study we examined whether prevalence information and imagery encoding influence participants' general plausibility, personal plausibility, belief, and memory ratings for suggested childhood events. Results showed decreases in general and personal plausibility ratings for low prevalence events when encoding instructions were not elaborate; however, instructions to repeatedly imagine suggested events elicited personal plausibility increases for low-prevalence events, evidence that elaborate imagery negated the effect of our prevalence manipulation. We found no evidence of imagination inflation or false memory construction. We discuss critical differences in researchers' manipulations of plausibility and imagery that may influence results of false memory studies in the literature. In future research investigators should focus on the specific nature of encoding instructions when examining the development of false memories.

Using the false memory paradigm to test two key elements of alcohol expectancy theory.

PubMed

Reich, Richard R; Goldman, Mark S; Noll, Jane A

2004-05-01

Two key aspects of alcohol expectancy theory--(a) that memories about alcohol effects are stored as relatively cohesive templates of information and (b) that these templates are automatically activated in alcohol-related contexts--were tested using the Deese-Roediger- McDermott false memory paradigm. Alcohol expectancy adjectives were studied, and false memory for expectancy target words was tested in neutral and alcohol contexts. Results indicated that in the alcohol context heavier drinkers showed more false memory for alcohol expectancy words than they did in a neutral context. Differences were not found for lighter drinkers. These results were consistent with alcohol expectancy theory, which was then compared with various forms of association theory in explaining these results and larger issues in the addiction field. ((c) 2004 APA, all rights reserved)

Effects of hydrocortisone on false memory recognition in healthy men and women.

PubMed

Duesenberg, Moritz; Weber, Juliane; Schaeuffele, Carmen; Fleischer, Juliane; Hellmann-Regen, Julian; Roepke, Stefan; Moritz, Steffen; Otte, Christian; Wingenfeld, Katja

2016-12-01

Most of the studies focusing on the effect of stress on false memories by using psychosocial and physiological stressors yielded diverse results. In the present study, we systematically tested the effect of exogenous hydrocortisone using a false memory paradigm. In this placebo-controlled study, 37 healthy men and 38 healthy women (mean age 24.59 years) received either 10 mg of hydrocortisone or placebo 75 min before using the false memory, that is, Deese-Roediger-McDermott (DRM), paradigm. We used emotionally charged and neutral DRM-based word lists to look for false recognition rates in comparison to true recognition rates. Overall, we expected an increase in false memory after hydrocortisone compared to placebo. No differences between the cortisol and the placebo group were revealed for false and for true recognition performance. In general, false recognition rates were lower compared to true recognition rates. Furthermore, we found a valence effect (neutral, positive, negative, disgust word stimuli), indicating higher rates of true and false recognition for emotional compared to neutral words. We further found an interaction effect between sex and recognition. Post hoc t tests showed that for true recognition women showed a significantly better memory performance than men, independent of treatment. This study does not support the hypothesis that cortisol decreases the ability to distinguish between old versus novel words in young healthy individuals. However, sex and emotional valence of word stimuli appear to be important moderators. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Study Modality and False Recall: The Influence of Resource Availability

PubMed Central

Smith, Rebekah E.; Engle, Randall W.

2010-01-01

False memories occur when individuals mistakenly report an event as having taken place when that event did not in fact occur. The DRM (Deese, 1959; Roediger & McDermott, 1995) paradigm provides an effective technique for creating and investigating false memories. In this paradigm participants study a list of words (e.g., SOUR, CANDY,…) that are highly associated to a non-presented critical item (e.g., SWEET). The study phase is followed by a test of memory for the study list words. Researchers typically find very high levels of false recall of the critical non-presented item. However, the likelihood of falsely remembering the non-presented critical items can be reduced by presenting studied associates visually rather than auditorally (e.g. Smith & Hunt, 1998). This is referred to as the modality effect in false memory. The current study investigated the role of resource availability in the expression of this modality effect in false recall. In Experiment 1 false recall was reduced in the visual study presentation condition relative to the auditory condition for participants with higher working memory capacity, but not for participants with lower working memory capacity. In Experiment 2 the effect of study modality on false recall was eliminated by the addition of a divided attention task at encoding. Both studies support the proposal that resource availability plays a role in the expression of the modality effect in the DRM paradigm (Smith, Lozito, & Bayen, 2005). PMID:20494859

True or false? Memory is differentially affected by stress-induced cortisol elevations and sympathetic activity at consolidation and retrieval.

PubMed

Smeets, Tom; Otgaar, Henry; Candel, Ingrid; Wolf, Oliver T

2008-11-01

Adrenal stress hormones released in response to acute stress may yield memory-enhancing effects when released post-learning and impairing effects at memory retrieval, especially for emotional memory material. However, so far these differential effects of stress hormones on the various memory phases for neutral and emotional memory material have not been demonstrated within one experiment. This study investigated whether, in line with their effects on true memory, stress and stress-induced adrenal stress hormones affect the encoding, consolidation, and retrieval of emotional and neutral false memories. Participants (N=90) were exposed to a stressor before encoding, during consolidation, before retrieval, or were not stressed and then were subjected to neutral and emotional versions of the Deese-Roediger-McDermott word list learning paradigm. Twenty-four hours later, recall of presented words (true recall) and non-presented critical lure words (false recall) was assessed. Results show that stress exposure resulted in superior true memory performance in the consolidation stress group and reduced true memory performance in the retrieval stress group compared to the other groups, predominantly for emotional words. These memory-enhancing and memory-impairing effects were strongly related to stress-induced cortisol and sympathetic activity measured via salivary alpha-amylase levels. Neutral and emotional false recall, on the other hand, was neither affected by stress exposure, nor related to cortisol and sympathetic activity following stress. These results demonstrate the importance of stress-induced hormone-related activity in enhancing memory consolidation and in impairing memory retrieval, in particular for emotional memory material.

False Belief vs. False Photographs: A Test of Theory of Mind or Working Memory?

PubMed

Callejas, Alicia; Shulman, Gordon L; Corbetta, Maurizio

2011-01-01

Theory of mind (ToM), the ability to reason about other people's thoughts and beliefs, has been traditionally studied in behavioral and neuroimaging experiments by comparing performance in "false belief" and "false photograph" (control) stories. However, some evidence suggests that these stories are not matched in difficulty, complicating the interpretation of results. Here, we more fully evaluated the relative difficulty of comprehending these stories and drawing inferences from them. Subjects read false belief and false photograph stories followed by comprehension questions that probed true ("reality" questions) or false beliefs ("representation" questions) appropriate to the stories. Stories and comprehension questions were read and answered, respectively, more slowly in the false photograph than false belief conditions, indicating their greater difficulty. Interestingly, accuracy on representation questions for false photograph stories was significantly lower than for all other conditions and correlated positively with participants' working memory span scores. These results suggest that drawing representational inferences from false photo stories is particularly difficult and places heavy demands on working memory. Extensive naturalistic practice with ToM reasoning may enable a more flexible and efficient mental representation of false belief stories, resulting in lower memory load requirements. An important implication of these results is that the differential modulation of right temporal-parietal junction (RTPJ) during ToM and "false photo" control conditions may reflect the documented negative correlation of RTPJ activity with working memory load rather than a specialized involvement in ToM processes.

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

PubMed

Strange, Deryn; Wade, Kimberley; Hayne, Harlene

2008-01-01

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

Differences in Binding and Monitoring Mechanisms Contribute to Lifespan Age Differences in False Memory

ERIC Educational Resources Information Center

Fandakova, Yana; Shing, Yee Lee; Lindenberger, Ulman

2013-01-01

Based on a 2-component framework of episodic memory development across the lifespan (Shing & Lindenberger, 2011), we examined the contribution of memory-related binding and monitoring processes to false memory susceptibility in childhood and old age. We administered a repeated continuous recognition task to children (N = 20, 10-12 years),…

Reliability of Children’s Testimony in the Era of Developmental Reversals

PubMed Central

Brainerd, C. J.; Reyna, V. F.

2012-01-01

A hoary assumption of the law is that children are more prone to false-memory reports than adults, and hence, their testimony is less reliable than adults’. Since the 1980s, that assumption has been buttressed by numerous studies that detected declines in false memory between early childhood and young adulthood under controlled conditions. Fuzzy-trace theory predicted reversals of this standard developmental pattern in circumstances that are directly relevant to testimony because they involve using the gist of experience to remember events. That prediction has been investigated during the past decade, and a large number of experiments have been published in which false memories have indeed been found to increase between early childhood and young adulthood. Further, experimentation has tied age increases in false memory to improvements in children’s memory for semantic gist. According to current scientific evidence, the principle that children’s testimony is necessarily more infected with false memories than adults’ and that, other things being equal, juries should regard adult’s testimony as necessarily more faithful to actual events is untenable. PMID:23139439

Serotonin–mushroom body circuit modulating the formation of anesthesia-resistant memory in Drosophila

PubMed Central

Lee, Pei-Tseng; Lin, Hsuan-Wen; Chang, Yu-Hsuan; Fu, Tsai-Feng; Dubnau, Josh; Hirsh, Jay; Lee, Tzumin; Chiang, Ann-Shyn

2011-01-01

Pavlovian olfactory learning in Drosophila produces two genetically distinct forms of intermediate-term memories: anesthesia-sensitive memory, which requires the amnesiac gene, and anesthesia-resistant memory (ARM), which requires the radish gene. Here, we report that ARM is specifically enhanced or inhibited in flies with elevated or reduced serotonin (5HT) levels, respectively. The requirement for 5HT was additive with the memory defect of the amnesiac mutation but was occluded by the radish mutation. This result suggests that 5HT and Radish protein act on the same pathway for ARM formation. Three supporting lines of evidence indicate that ARM formation requires 5HT released from only two dorsal paired medial (DPM) neurons onto the mushroom bodies (MBs), the olfactory learning and memory center in Drosophila: (i) DPM neurons were 5HT-antibody immunopositive; (ii) temporal inhibition of 5HT synthesis or release from DPM neurons, but not from other serotonergic neurons, impaired ARM formation; (iii) knocking down the expression of d5HT1A serotonin receptors in α/β MB neurons, which are innervated by DPM neurons, inhibited ARM formation. Thus, in addition to the Amnesiac peptide required for anesthesia-sensitive memory formation, the two DPM neurons also release 5HT acting on MB neurons for ARM formation. PMID:21808003

Audiovisual integration supports face-name associative memory formation.

PubMed

Lee, Hweeling; Stirnberg, Rüdiger; Stöcker, Tony; Axmacher, Nikolai

2017-10-01

Prior multisensory experience influences how we perceive our environment, and hence how memories are encoded for subsequent retrieval. This study investigated if audiovisual (AV) integration and associative memory formation rely on overlapping or distinct processes. Our functional magnetic resonance imaging results demonstrate that the neural mechanisms underlying AV integration and associative memory overlap substantially. In particular, activity in anterior superior temporal sulcus (STS) is increased during AV integration and also determines the success of novel AV face-name association formation. Dynamic causal modeling results further demonstrate how the anterior STS interacts with the associative memory system to facilitate successful memory formation for AV face-name associations. Specifically, the connection of fusiform gyrus to anterior STS is enhanced while the reverse connection is reduced when participants subsequently remembered both face and name. Collectively, our results demonstrate how multisensory associative memories can be formed for subsequent retrieval.

Hypnosis

MedlinePlus

... or dizziness Anxiety or distress Creation of false memories Use special caution before using hypnosis for age regression to help you relive earlier ... your memories or lead to creation of false memories. How you prepare You ... preparation to undergo hypnosis. But it's a good idea to wear comfortable ...

HDAC7 Ubiquitination by the E3 Ligase CBX4 Is Involved in Contextual Fear Conditioning Memory Formation.

PubMed

Jing, Xu; Sui, Wen-Hai; Wang, Shuai; Xu, Xu-Feng; Yuan, Rong-Rong; Chen, Xiao-Rong; Ma, Hui-Xian; Zhu, Ying-Xiao; Sun, Jin-Kai; Yi, Fan; Chen, Zhe-Yu; Wang, Yue

2017-04-05

Histone acetylation, an epigenetic modification, plays an important role in long-term memory formation. Recently, histone deacetylase (HDAC) inhibitors were demonstrated to promote memory formation, which raises the intriguing possibility that they may be used to rescue memory deficits. However, additional research is necessary to clarify the roles of individual HDACs in memory. In this study, we demonstrated that HDAC7, within the dorsal hippocampus of C57BL6J mice, had a late and persistent decrease after contextual fear conditioning (CFC) training (4-24 h), which was involved in long-term CFC memory formation. We also showed that HDAC7 decreased via ubiquitin-dependent degradation. CBX4 was one of the HDAC7 E3 ligases involved in this process. Nur77, as one of the target genes of HDAC7, increased 6-24 h after CFC training and, accordingly, modulated the formation of CFC memory. Finally, HDAC7 was involved in the formation of other hippocampal-dependent memories, including the Morris water maze and object location test. The current findings facilitate an understanding of the molecular and cellular mechanisms of HDAC7 in the regulation of hippocampal-dependent memory. SIGNIFICANCE STATEMENT The current findings demonstrated the effects of histone deacetylase 7 (HDAC7) on hippocampal-dependent memories. Moreover, we determined the mechanism of decreased HDAC7 in contextual fear conditioning (CFC) through ubiquitin-dependent protein degradation. We also verified that CBX4 was one of the HDAC7 E3 ligases. Finally, we demonstrated that Nur77, as one of the important targets for HDAC7, was involved in CFC memory formation. All of these proteins, including HDAC7, CBX4, and Nur77, could be potential therapeutic targets for preventing memory deficits in aging and neurological diseases. Copyright © 2017 the authors 0270-6474/17/373848-16$15.00/0.

Emotionally negative pictures enhance gist memory.

PubMed

Bookbinder, S H; Brainerd, C J

2017-02-01

In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are caused by valence and which are caused by arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling revealed that negative valence (a) reduced erroneous suppression of true memories and (b) increased the familiarity of the semantic content of both true and false memories. Overall, negative valence impaired the verbatim side of episodic memory but enhanced the gist side, and these effects persisted even after a week-long delay. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The many faces of amnesia.

PubMed

Gold, Paul E

2006-01-01

Results from studies of retrograde amnesia provide much of the evidence for theories of memory consolidation. Retrograde amnesia gradients are often interpreted as revealing the time needed for the formation of long-term memories. The rapid forgetting observed after many amnestic treatments, including protein synthesis inhibitors, and the parallel decay seen in long-term potentiation experiments are presumed to reveal the duration of short-term memory processing. However, there is clear and consistent evidence that the time courses obtained in these amnesia experiments are highly variable within and across experiments and treatments. The evidence is inconsistent with identification of basic temporal properties of memory consolidation. Alternative views include modulation of memory and emphasize the roles that hormones and neurotransmitters have in regulating memory formation. Of related interest, converging lines of evidence suggest that inhibitors of protein synthesis and of other biochemical processes act on modulators of memory formation rather than on mechanisms of memory formation. Based on these findings, memory consolidation and reconsolidation studies might better be identified as memory modulation and "remodulation" studies. Beyond a missing and perhaps unattainable time constant of memory consolidation, some current views of memory consolidation assume that memories, once formed, are generally unmodifiable. It is this perspective that appears to have led to the recent interest in memory reconsolidation. But the view adopted here is that memories are continually malleable, being updated by new experiences and, at the same time, altering the memories of later experiences. Studies of memory remodulation offer promise of understanding the neurobiological bases by which new memories are altered by prior experiences and by which old memories are altered by new experiences.

Exposure to suggestion and creation of false auditory memories.

PubMed

Vernon, B; Nelson, E

2000-02-01

The experiment investigated the possibility of creating false auditory memory through exposure to suggestion. Research by Loftus and others has indicated that, through suggestion, false memories can be created. Participants viewed a short film and were given a 9-item questionnaire. Eight questions were used as filler while one question asked respondents to recall a phrase one character had said. Although the character actually said nothing, 23 of 30 respondents recalled having heard him speak and specifically recalled his words. This statistically significant result shows that auditory memories can also be created.

Stereotypes influence false memories for imagined events.

PubMed

Kleider, Heather M; Goldinger, Stephen D; Knuycky, Leslie

2008-02-01

Two experiments tested the influences of vivid imagery and person schemata on eyewitness accuracy. Participants watched an event sequence including actors performing stereotype-consistent and inconsistent actions. Additionally, participants either read descriptions of actions (Experiment 1) or vividly imagined actions (Experiment 2). After either 30 minutes or 2 days, recognition memory, source memory, and remember/know judgements were made. After 2 days, false alarms to imagined events increased, relative to the 30-minute test; those false alarms were more often misattributed to stereotype-consistent actors, relative to the same actions in the reading condition. In addition, the accompanying remember judgements were higher for false alarms to imagined events, relative to read events, regardless of stereotype consistency. Overall the results suggest that, over time, vivid imagery reinforces schema activation, increasing stereotype-consistent false memories.

The neurobiological bases of memory formation: from physiological conditions to psychopathology.

PubMed

Bisaz, Reto; Travaglia, Alessio; Alberini, Cristina M

2014-01-01

The formation of long-term memories is a function necessary for an adaptive survival. In the last two decades, great progress has been made in the understanding of the biological bases of memory formation. The identification of mechanisms necessary for memory consolidation and reconsolidation, the processes by which the posttraining and postretrieval fragile memory traces become stronger and insensitive to disruption, has indicated new approaches for investigating and treating psychopathologies. In this review, we will discuss some key biological mechanisms found to be critical for memory consolidation and strengthening, the role/s and mechanisms of memory reconsolidation, and how the interference with consolidation and/or reconsolidation can modulate the retention and/or storage of memories that are linked to psychopathologies. © 2014 S. Karger AG, Basel.

The Role of Ephs and Ephrins in Memory Formation.

PubMed

Dines, Monica; Lamprecht, Raphael

2016-04-01

The ability to efficiently store memories in the brain is a fundamental process and its impairment is associated with multiple human mental disorders. Evidence indicates that long-term memory formation involves alterations of synaptic efficacy produced by modifications in neural transmission and morphology. The Eph receptors and their cognate ephrin ligands have been shown to be involved in these key neuronal processes by regulating events such as presynaptic transmitter release, postsynaptic glutamate receptor conductance and trafficking, synaptic glutamate reuptake, and dendritic spine morphogenesis. Recent findings show that Ephs and ephrins are needed for memory formation in different organisms. These proteins participate in the formation of various types of memories that are subserved by different neurons and brain regions. Ephs and ephrins are involved in brain disorders and diseases with memory impairment symptoms, including Alzheimer's disease and anxiety. Drugs that agonize or antagonize Ephs/ephrins signaling have been developed and could serve as therapeutic agents to treat such diseases. Ephs and ephrins may therefore induce cellular alterations mandatory for memory formation and serve as a target for pharmacological intervention for treatment of memory-related brain diseases. © The Author 2015. Published by Oxford University Press on behalf of CINP.

Patterns of False Memory in Patients with Huntington's Disease.

PubMed

Chen, I-Wen; Chen, Chiung-Mei; Wu, Yih-Ru; Hua, Mau-Sun

2017-06-01

Increased false memory recognition in patients with Huntington's disease (HD) has been widely reported; however, the underlying memory constructive processes remain unclear. The present study explored gist memory, item-specific memory, and monitoring ability in patients with HD. Twenty-five patients (including 13 patients with mild HD and 12 patients with moderate-to-severe HD) and 30 healthy comparison participants (HC) were recruited. We used the Deese-Roediger-McDermott (DRM) paradigm to investigate participants' false recognition patterns, along with neuropsychological tests to assess general cognitive function. Both mild and moderate-to-severe patients with HD showed significant executive functioning and episodic memory impairment. On the DRM tasks, both HD patient groups showed significantly impaired performance in tasks assessing unrelated false recognition and item-specific memory as compared to the HC group; moderate-to-severe patients performed more poorly than mild patients did. Only moderate-severe patients exhibited significantly poorer related false recognition index scores than HCs in the verbal DRM task; performance of HD patient groups was comparable to the HC group on the pictorial DRM task. It appears that diminished verbatim memory and monitoring ability are early signs of cognitive decline during the HD course. Conversely, gist memory is relatively robust, with only partial decline during advanced-stage HD. Our findings suggest that medial temporal lobe function is relatively preserved compared to that of frontal-related structures in early HD. Thus, gist-based memory rehabilitation programs might be beneficial for patients with HD. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke–Korsakoff syndrome

PubMed Central

Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi

2016-01-01

Patients with severe Wernicke–Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation. PMID:27576603

Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke-Korsakoff syndrome.

PubMed

Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi

2016-12-01

Patients with severe Wernicke-Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation.

Is the truth in the details? Extended narratives help distinguishing false "memories" from false "reports".

PubMed

Sjödén, Björn; Granhag, Pär Anders; Ost, James; Roos Af Hjelmsäter, Emma

2009-06-01

The present study examined the effects of fantasy proneness on false "reports" and false "memories", of existent and non-existent footage of a public event. We predicted that highly fantasy prone individuals would be more likely to stand by their initial claim of having seen a film of the event than low fantasy prone participants when prompted for more details about their experiences. Eighty creative arts students and 80 other students were asked whether they had seen CCTV footage preceding the attack on Swedish foreign minister Anna Lindh up to, and including, non-existent footage of the actual moment of the attack. If affirmative, they were probed for extended narratives of what they claimed to have seen. Overall, 64% of participants provided a false "report" by answering yes to the initial question. Of these, 30% provided no explicit details of the attack, and a further 15% retracted their initial answer in their narratives. This left 19% of the sample who appeared to have false "memories" because they provided explicit details of the actual moment of the attack. Women scored higher than men and art students scored higher than other students on fantasy proneness, but there was no effect on levels of false reporting or false "memory". Memories were rated more vivid and clear for existent compared to non-existent aspects of the event. In sum, these data suggest a more complex relationship between memory distortions and fantasy proneness than previously observed.

The effect of mood on false memory for emotional DRM word lists.

PubMed

Zhang, Weiwei; Gross, Julien; Hayne, Harlene

2017-04-01

In the present study, we investigated the effect of participants' mood on true and false memories of emotional word lists in the Deese-Roediger-McDermott (DRM) paradigm. In Experiment 1, we constructed DRM word lists in which all the studied words and corresponding critical lures reflected a specified emotional valence. In Experiment 2, we used these lists to assess mood-congruent true and false memory. Participants were randomly assigned to one of three induced-mood conditions (positive, negative, or neutral) and were presented with word lists comprised of positive, negative, or neutral words. For both true and false memory, there was a mood-congruent effect in the negative mood condition; this effect was due to a decrease in true and false recognition of the positive and neutral words. These findings are consistent with both spreading-activation and fuzzy-trace theories of DRM performance and have practical implications for our understanding of the effect of mood on memory.

Can false memory for critical lures occur without conscious awareness of list words?

PubMed

Sadler, Daniel D; Sodmont, Sharon M; Keefer, Lucas A

2018-02-01

We examined whether the DRM false memory effect can occur when list words are presented below the perceptual identification threshold. In four experiments, subjects showed robust veridical memory for studied words and false memory for critical lures when masked list words were presented at exposure durations of 43 ms per word. Shortening the exposure duration to 29 ms virtually eliminated veridical recognition of studied words and completely eliminated false recognition of critical lures. Subjective visibility ratings in Experiments 3a and 3b support the assumption that words presented at 29 ms were subliminal for most participants, but were occasionally experienced with partial awareness by participants with higher perceptual awareness. Our results indicate that a false memory effect does not occur in the absence of conscious awareness of list words, but it does occur when word stimuli are presented at an intermediate level of visibility. Copyright © 2017 Elsevier Inc. All rights reserved.

Positive events protect children from causal false memories for scripted events.

PubMed

Melinder, Annika; Toffalini, Enrico; Geccherle, Eleonora; Cornoldi, Cesare

2017-11-01

Adults produce fewer inferential false memories for scripted events when their conclusions are emotionally charged than when they are neutral, but it is not clear whether the same effect is also found in children. In the present study, we examined this issue in a sample of 132 children aged 6-12 years (mean 9 years, 3 months). Participants encoded photographs depicting six script-like events that had a positively, negatively, or a neutral valenced ending. Subsequently, true and false recognition memory of photographs related to the observed scripts was tested as a function of emotionality. Causal errors-a type of false memory thought to stem from inferential processes-were found to be affected by valence: children made fewer causal errors for positive than for neutral or negative events. Hypotheses are proposed on why adults were found protected against inferential false memories not only by positive (as for children) but also by negative endings when administered similar versions of the same paradigm.

Word type effects in false recall: concrete, abstract, and emotion word critical lures.

PubMed

Bauer, Lisa M; Olheiser, Erik L; Altarriba, Jeanette; Landi, Nicole

2009-01-01

Previous research has demonstrated that definable qualities of verbal stimuli have implications for memory. For example, the distinction between concrete and abstract words has led to the finding that concrete words have an advantage in memory tasks (i.e., the concreteness effect). However, other word types, such as words that label specific human emotions, may also affect memory processes. This study examined the effects of word type on the production of false memories by using a list-learning false memory paradigm. Participants heard lists of words that were highly associated to nonpresented concrete, abstract, or emotion words (i.e., the critical lures) and then engaged in list recall. Emotion word critical lures were falsely recalled at a significantly higher rate (with the effect carried by the positively valenced critical lures) than concrete and abstract critical lures. These findings suggest that the word type variable has implications for our understanding of the mechanisms that underlie recall and false recall.

Is there a false memory syndrome? A review of three cases.

PubMed

Kaplan, R; Manicavasagar, V

2001-01-01

The controversy over recovered memories of childhood sexual abuse (CSA) is whether such experiences can be forgotten for long periods and retrieved later in therapy or in response to cues or triggers from the environment. False memory syndrome (FMS) is caused by memories of a traumatic experience--most frequently CSA--which are objectively false, but in which the person strongly believes. Personality factors often play a role in the development of FMS. Because CSA is such a devastating experience, false accusations of sexual abuse have enormous, if not shattering, consequences for families. We present three case reports to illustrate features of the FMS. FMS should be listed for further study to establish valid criteria for making the diagnosis under the category of "factitious disorders," and a subcategory of "false memories/beliefs of abuse," with a further subdivision of "induced by therapy." The FMS controversy occurred in the context of a general moral panic about sexual abuse in the early 1980s. Psychiatrists should have a high degree of scepticism to moral panics.

Disfluent presentations lead to the creation of more false memories.

PubMed

Sanchez, Christopher A; Naylor, Jamie S

2018-01-01

The creation of false memories within the Deese-Roediger-McDermott (DRM) paradigm has been shown to be sensitive to many factors such as task instructions, participant mood, or even presentation modality. However, do other simple perceptual differences also impact performance on the DRM and the creation of false memories? This study explores the potential impact of changes in perceptual disfluency on DRM performance. To test for a potential influence of disfluency on false memory creation, participants viewed lists under either perceptually disfluent conditions or not. Results indicated that disfluency did significantly impact performance in the DRM paradigm; more disfluent presentations significantly increased the recall and recognition of unpresented information, although they did not impact recall or recognition of presented information. Thus, although disfluency did impact performance, disfluency did not produce a positive benefit related to overall task performance. This finding instead suggests that more disfluent presentations can increase the likelihood that false memories are created, and provide little positive performance benefit.

Disfluent presentations lead to the creation of more false memories

PubMed Central

Naylor, Jamie S.

2018-01-01

The creation of false memories within the Deese-Roediger-McDermott (DRM) paradigm has been shown to be sensitive to many factors such as task instructions, participant mood, or even presentation modality. However, do other simple perceptual differences also impact performance on the DRM and the creation of false memories? This study explores the potential impact of changes in perceptual disfluency on DRM performance. To test for a potential influence of disfluency on false memory creation, participants viewed lists under either perceptually disfluent conditions or not. Results indicated that disfluency did significantly impact performance in the DRM paradigm; more disfluent presentations significantly increased the recall and recognition of unpresented information, although they did not impact recall or recognition of presented information. Thus, although disfluency did impact performance, disfluency did not produce a positive benefit related to overall task performance. This finding instead suggests that more disfluent presentations can increase the likelihood that false memories are created, and provide little positive performance benefit. PMID:29370255

Identification of a novel protein for memory regulation in the hippocampus.

PubMed

Zhang, Xue-Han; Zhang, Hui; Tu, Yanyang; Gao, Xiang; Zhou, Changfu; Jin, Meilei; Zhao, Guoping; Jing, Naihe; Li, Bao-Ming; Yu, Lei

2005-08-26

Memory formation, maintenance, and retrieval are a dynamic process, reflecting a combined outcome of new memory formation on one hand, and older memory suppression/clearance on the other. Although much knowledge has been gained regarding new memory formation, less is known about the molecular components and processes that serve the function of memory suppression/clearance. Here, we report the identification of a novel protein, termed hippyragranin (HGN), that is expressed in the rat hippocampus and its expression is reduced by hippocampal denervation. Inhibition of HGN by antisense oligonucleotide in area CA1 results in enhanced performance in Morris water maze, as well as elevated long-term potentiation. These results suggest that HGN is involved in negative memory regulation.

Cognitive Processes Supporting Episodic Memory Formation in Childhood: The Role of Source Memory, Binding, and Executive Functioning

ERIC Educational Resources Information Center

Raj, Vinaya; Bell, Martha Ann

2010-01-01

Episodic memories contain various forms of contextual detail (e.g., perceptual, emotional, cognitive details) that need to become integrated. Each of these contextual features can be used to attribute a memory episode to its source, or origin of information. Memory for source information is one critical component in the formation of episodic…

Molecular brake pad hypothesis: pulling off the brakes for emotional memory

PubMed Central

Vogel-Ciernia, Annie

2015-01-01

Under basal conditions histone deacetylases (HDACs) and their associated co-repressor complexes serve as molecular ‘brake pads’ to prevent the gene expression required for long-term memory formation. Following a learning event, HDACs and their co-repressor complexes are removed from a subset of specific gene promoters, allowing the histone acetylation and active gene expression required for long-term memory formation. Inhibition of HDACs increases histone acetylation, extends gene expression profiles, and allows for the formation of persistent long-term memories for training events that are otherwise forgotten. We propose that emotionally salient experiences have utilized this system to form strong and persistent memories for behaviorally significant events. Consequently, the presence or absence of HDACs at a selection of specific gene promoters could serve as a critical barrier for permitting the formation of long-term memories. PMID:23096102

False Memory for Trauma-Related DRM Lists in Adolescents and Adults with Histories of Child Sexual Abuse

PubMed Central

Goodman, Gail S.; Ogle, Christin M.; Block, Stephanie D.; Harris, LaTonya S.; Larson, Rakel P.; Augusti, Else-Marie; Cho, Young Il; Beber, Jonathan; Timmer, Susan; Urquiza, Anthony

2014-01-01

The purpose of the present research was to examine Deese-Roediger-McDermott (DRM) false memory for trauma-related and nontrauma-related lists in adolescents and adults with and without documented histories of child sexual abuse (CSA). Individual differences in psychopathology and adult attachment were also explored. Participants were administered free recall and recognition tests after hearing CSA, negative, neutral, and positive DRM lists. In free recall, CSA and negative lists produced the most false memory. In sharp contrast, for recognition, CSA lists enjoyed the highest d’ scores. CSA-group adolescents who evinced greater PTSD symptoms had higher rates of false memory compared to: 1) nonCSA-group adolescents with higher PTSD symptom scores (free recall), and 2) CSA-group adolescents with lower PTSD symptom scores (recognition). Regression analyses revealed that individuals with higher PTSD scores and greater fearful-avoidant attachment tendencies showed less proficient memory monitoring for CSA lists. Implications for trauma and memory development and for translational research are discussed. PMID:23786687

Differential effects of ongoing EEG beta and theta power on memory formation

PubMed Central

Scholz, Sebastian; Schneider, Signe Luisa

2017-01-01

Recently, elevated ongoing pre-stimulus beta power (13–17 Hz) at encoding has been associated with subsequent memory formation for visual stimulus material. It is unclear whether this activity is merely specific to visual processing or whether it reflects a state facilitating general memory formation, independent of stimulus modality. To answer that question, the present study investigated the relationship between neural pre-stimulus oscillations and verbal memory formation in different sensory modalities. For that purpose, a within-subject design was employed to explore differences between successful and failed memory formation in the visual and auditory modality. Furthermore, associative memory was addressed by presenting the stimuli in combination with background images. Results revealed that similar EEG activity in the low beta frequency range (13–17 Hz) is associated with subsequent memory success, independent of stimulus modality. Elevated power prior to stimulus onset differentiated successful from failed memory formation. In contrast, differential effects between modalities were found in the theta band (3–7 Hz), with an increased oscillatory activity before the onset of later remembered visually presented words. In addition, pre-stimulus theta power dissociated between successful and failed encoding of associated context, independent of the stimulus modality of the item itself. We therefore suggest that increased ongoing low beta activity reflects a memory promoting state, which is likely to be moderated by modality-independent attentional or inhibitory processes, whereas high ongoing theta power is suggested as an indicator of the enhanced binding of incoming interlinked information. PMID:28192459

Cdk5 Is Required for Memory Function and Hippocampal Plasticity via the cAMP Signaling Pathway

PubMed Central

Gao, Jun; Joseph, Nadine; Xie, Zhigang; Zhou, Ying; Durak, Omer; Zhang, Lei; Zhu, J. Julius; Clauser, Karl R.; Carr, Steven A.; Tsai, Li-Huei

2011-01-01

Memory formation is modulated by pre- and post-synaptic signaling events in neurons. The neuronal protein kinase Cyclin-Dependent Kinase 5 (Cdk5) phosphorylates a variety of synaptic substrates and is implicated in memory formation. It has also been shown to play a role in homeostatic regulation of synaptic plasticity in cultured neurons. Surprisingly, we found that Cdk5 loss of function in hippocampal circuits results in severe impairments in memory formation and retrieval. Moreover, Cdk5 loss of function in the hippocampus disrupts cAMP signaling due to an aberrant increase in phosphodiesterase (PDE) proteins. Dysregulation of cAMP is associated with defective CREB phosphorylation and disrupted composition of synaptic proteins in Cdk5-deficient mice. Rolipram, a PDE4 inhibitor that prevents cAMP depletion, restores synaptic plasticity and memory formation in Cdk5-deficient mice. Collectively, our results demonstrate a critical role for Cdk5 in the regulation of cAMP-mediated hippocampal functions essential for synaptic plasticity and memory formation. PMID:21984943

Human hippocampus associates information in memory

PubMed Central

Henke, Katharina; Weber, Bruno; Kneifel, Stefan; Wieser, Heinz Gregor; Buck, Alfred

1999-01-01

The hippocampal formation, one of the most complex and vulnerable brain structures, is recognized as a crucial brain area subserving human long-term memory. Yet, its specific functions in memory are controversial. Recent experimental results suggest that the hippocampal contribution to human memory is limited to episodic memory, novelty detection, semantic (deep) processing of information, and spatial memory. We measured the regional cerebral blood flow by positron-emission tomography while healthy volunteers learned pairs of words with different learning strategies. These led to different forms of learning, allowing us to test the degree to which they challenge hippocampal function. Neither novelty detection nor depth of processing activated the hippocampal formation as much as semantically associating the primarily unrelated words in memory. This is compelling evidence for another function of the human hippocampal formation in memory: establishing semantic associations. PMID:10318979

Disowned recollections: denying true experiences undermines belief in occurrence but not judgments of remembering.

PubMed

Mazzoni, Giuliana; Clark, Andrew; Nash, Robert A

2014-01-01

Recent research findings have illustrated that false memories induced in the laboratory can be dissociated from the beliefs that the events had in fact occurred. In this study we assessed whether this dissociability is a quality peculiar to false memory, or whether it represents a general characteristic of autobiographical memory. To this end we examined whether people can be induced to stop believing in memories for true experiences. Participants observed and performed simple actions, and were later falsely informed that they had not performed some of them--that false memories for these actions had been implanted through the use of fabricated evidence. Before and after receiving this misinformation, participants rated their belief in and memory of performing those actions, other actions that they had also performed, and actions that they had not performed. Whereas the misinformation substantially undermined participants' beliefs in the specific performed actions about which they had been misinformed, it had little effect on their endorsement of remembering those actions. The misinformation thus boosted the proportion of occasions in which participants rated their memories as stronger than their beliefs, and it weakened the correlation between belief and memory ratings. Thus, this study provides the first experimental demonstration of non-believed memories of true experiences. We discuss our findings with reference to the small literature concerning the use of socially-communicated misinformation to undermine event memories, and with reference to the structure of autobiographical memory. Copyright © 2013 Elsevier B.V. All rights reserved.

Brain activation for reading and listening comprehension: An fMRI study of modality effects and individual differences in language comprehension

PubMed Central

Buchweitz, Augusto; Mason, Robert A.; Tomitch, Lêda M. B.; Just, Marcel Adam

2010-01-01

The study compared the brain activation patterns associated with the comprehension of written and spoken Portuguese sentences. An fMRI study measured brain activity while participants read and listened to sentences about general world knowledge. Participants had to decide if the sentences were true or false. To mirror the transient nature of spoken sentences, visual input was presented in rapid serial visual presentation format. The results showed a common core of amodal left inferior frontal and middle temporal gyri activation, as well as modality specific brain activation associated with listening and reading comprehension. Reading comprehension was associated with more left-lateralized activation and with left inferior occipital cortex (including fusiform gyrus) activation. Listening comprehension was associated with extensive bilateral temporal cortex activation and more overall activation of the whole cortex. Results also showed individual differences in brain activation for reading comprehension. Readers with lower working memory capacity showed more activation of right-hemisphere areas (spillover of activation) and more activation in the prefrontal cortex, potentially associated with more demand placed on executive control processes. Readers with higher working memory capacity showed more activation in a frontal-posterior network of areas (left angular and precentral gyri, and right inferior frontal gyrus). The activation of this network may be associated with phonological rehearsal of linguistic information when reading text presented in rapid serial visual format. The study demonstrates the modality fingerprints for language comprehension and indicates how low- and high working memory capacity readers deal with reading text presented in serial format. PMID:21526132

Hippocampal SSTR4 somatostatin receptors control the selection of memory strategies.

PubMed

Gastambide, François; Viollet, Cécile; Lepousez, Gabriel; Epelbaum, Jacques; Guillou, Jean-Louis

2009-01-01

Somatostatin (SS14) has been implicated in various cognitive disorders, and converging evidence from animal studies suggests that SS14 neurons differentially regulate hippocampal- and striatal-dependent memory formation. Four SS14 receptor subtypes (SSTR1-4) are expressed in the hippocampus, but their respective roles in memory processes remain to be determined. In the present study, effects of selective SSTR1-4 agonists on memory formation were assessed in a water-maze task which can engage either hippocampus-dependent "place" and/or striatum-dependent "cue" memory formation. Mice received an intrahippocampal injection of one of each of the selective agonists and were then trained to locate an escape platform based on either distal cues (place memory) or a visible proximal cue (cue memory). Retention was tested 24 h later on probe trials aimed at identifying which memory strategy was preferentially retained. Both SS14 and the SSTR4 agonist (L-803,087) dramatically impaired place memory formation in a dose-dependent manner, whereas SSTR1 (L-797,591), SSTR2 (L-779,976), or SSTR3 (L-796,778) agonists did not yield any behavioral effects. However, unlike SS14, the SSTR4 agonist also dose-dependently enhanced cue-based memory formation. This effect was confirmed in another striatal-dependent memory task, the bar-pressing task, where L-803,087 improved memory of the instrumental response, whereas SS14 was once again ineffective. These data suggest that hippocampal SSTR4 are selectively involved in the selection of memory strategies by switching from the use of hippocampus-based multiple associations to the use of simple dorsal striatum-based behavioral responses. Possible neural mechanisms and functional implications are discussed.

Dissociation between Complete Hippocampal Context Memory Formation and Context Fear Acquisition

ERIC Educational Resources Information Center

Leake, Jessica; Zinn, Raphael; Corbit, Laura; Vissel, Bryce

2017-01-01

Rodents require a minimal time period to explore a context prior to footshock to display plateau-level context fear at test. To investigate whether this rapid fear plateau reflects complete memory formation within that short time-frame, we used the immediate-early gene product Arc as an indicator of hippocampal context memory formation-related…

Performance and process in collective and individual memory: the role of social decision schemes and memory bias in collective memory.

PubMed

Van Swol, Lyn M

2008-04-01

To assess performance and processes in collective and individual memory, participants watched two job candidates on video. Beforehand, half the participants were told they would be tested on their memory of the interviews, and the other half were asked to make a decision to hire one of the candidates. Afterwards, participants completed a recognition memory task in either a group or individual condition. Groups had better recognition memory than individuals. Individuals made more false positives than false negatives and groups exaggerated this. Post-hoc analysis found that groups only exaggerated the tendency towards false positives on items that reflected negatively on the job candidate. There was no significant difference between instruction conditions. When reaching consensus on the recognition task, groups tended to choose the correct answer if at least two members had the correct answer. This method of consensus is discussed as a factor in groups' superior memory performance.

True and false memory for colour names versus actual colours: support for the visual distinctiveness heuristic in memory for colour information.

PubMed

Eslick, Andrea N; Kostic, Bogdan; Cleary, Anne M

2010-06-01

In a colour variation of the Deese-Roediger-McDermott (DRM) false memory paradigm, participants studied lists of words critically related to a nonstudied colour name (e.g., "blood, cherry, scarlet, rouge ... "); they later showed false memory for the critical colour name (e.g., "red"). Two additional experiments suggest that participants generate colour imagery in response to such colour-related DRM lists. First, participants claim to experience colour imagery more often following colour-related than standard non-colour-related DRM lists; they also rate their colour imagery as more vivid following colour-related lists. Second, participants exhibit facilitative priming for critical colours in a dot selection task that follows words in the colour-related DRM list, suggesting that colour-related DRM lists prime participants for the actual critical colours themselves. Despite these findings, false memory for critical colour names does not extend to the actual colours themselves (font colours). Rather than leading to source confusion about which colours were self-generated and which were studied, presenting the study lists in varied font colours actually worked to reduce false memory overall. Results are interpreted within the framework of the visual distinctiveness hypothesis.

Event-related fMRI studies of false memory: An Activation Likelihood Estimation meta-analysis.

PubMed

Kurkela, Kyle A; Dennis, Nancy A

2016-01-29

Over the last two decades, a wealth of research in the domain of episodic memory has focused on understanding the neural correlates mediating false memories, or memories for events that never happened. While several recent qualitative reviews have attempted to synthesize this literature, methodological differences amongst the empirical studies and a focus on only a sub-set of the findings has limited broader conclusions regarding the neural mechanisms underlying false memories. The current study performed a voxel-wise quantitative meta-analysis using activation likelihood estimation to investigate commonalities within the functional magnetic resonance imaging (fMRI) literature studying false memory. The results were broken down by memory phase (encoding, retrieval), as well as sub-analyses looking at differences in baseline (hit, correct rejection), memoranda (verbal, semantic), and experimental paradigm (e.g., semantic relatedness and perceptual relatedness) within retrieval. Concordance maps identified significant overlap across studies for each analysis. Several regions were identified in the general false retrieval analysis as well as multiple sub-analyses, indicating their ubiquitous, yet critical role in false retrieval (medial superior frontal gyrus, left precentral gyrus, left inferior parietal cortex). Additionally, several regions showed baseline- and paradigm-specific effects (hit/perceptual relatedness: inferior and middle occipital gyrus; CRs: bilateral inferior parietal cortex, precuneus, left caudate). With respect to encoding, analyses showed common activity in the left middle temporal gyrus and anterior cingulate cortex. No analysis identified a common cluster of activation in the medial temporal lobe. Copyright © 2015 Elsevier Ltd. All rights reserved.

Lexical association and false memory for words in two cultures.

PubMed

Lee, Yuh-shiow; Chiang, Wen-Chi; Hung, Hsu-Ching

2008-01-01

This study examined the relationship between language experience and false memory produced by the DRM paradigm. The word lists used in Stadler, et al. (Memory & Cognition, 27, 494-500, 1999) were first translated into Chinese. False recall and false recognition for critical non-presented targets were then tested on a group of Chinese users. The average co-occurrence rate of the list word and the critical word was calculated based on two large Chinese corpuses. List-level analyses revealed that the correlation between the American and Taiwanese participants was significant only in false recognition. More importantly, the co-occurrence rate was significantly correlated with false recall and recognition of Taiwanese participants, and not of American participants. In addition, the backward association strength based on Nelson et al. (The University of South Florida word association, rhyme and word fragment norms, 1999) was significantly correlated with false recall of American participants and not of Taiwanese participants. Results are discussed in terms of the relationship between language experiences and lexical association in creating false memory for word lists.

The Regulation of Transcription in Memory Consolidation

PubMed Central

Alberini, Cristina M.; Kandel, Eric R.

2015-01-01

De novo transcription of DNA is a fundamental requirement for the formation of long-term memory. It is required during both consolidation and reconsolidation, the posttraining and postreactivation phases that change the state of the memory from a fragile into a stable and long-lasting form. Transcription generates both mRNAs that are translated into proteins, which are necessary for the growth of new synaptic connections, as well as noncoding RNA transcripts that have regulatory or effector roles in gene expression. The result is a cascade of events that ultimately leads to structural changes in the neurons that mediate long-term memory storage. The de novo transcription, critical for synaptic plasticity and memory formation, is orchestrated by chromatin and epigenetic modifications. The complexity of transcription regulation, its temporal progression, and the effectors produced all contribute to the flexibility and persistence of long-term memory formation. In this article, we provide an overview of the mechanisms contributing to this transcriptional regulation underlying long-term memory formation. PMID:25475090

Level of Processing Modulates the Neural Correlates of Emotional Memory Formation

ERIC Educational Resources Information Center

Ritchey, Maureen; LaBar, Kevin S.; Cabeza, Roberto

2011-01-01

Emotion is known to influence multiple aspects of memory formation, including the initial encoding of the memory trace and its consolidation over time. However, the neural mechanisms whereby emotion impacts memory encoding remain largely unexplored. The present study used a levels-of-processing manipulation to characterize the impact of emotion on…

Early memory formation disrupted by atypical PKC inhibitor ZIP in the medial prefrontal cortex but not hippocampus

PubMed Central

Evuarherhe, Obaro; Barker, Gareth R. I.; Savalli, Giorgia; Warburton, Elizabeth C.; Brown, Malcolm W.

2014-01-01

Atypical isoforms of protein kinase C (aPKCs; particularly protein kinase M zeta: PKMζ) have been hypothesised to be necessary and sufficient for the maintenance of long-term potentiation (LTP) and long term memory by maintaining postsynaptic AMPA receptors via the GluR2 subunit. A myristoylated PKMζ pseudosubstrate peptide (ZIP) blocks PKMζ activity. We examined the actions of ZIP in medial prefrontal cortex (mPFC) and hippocampus in associative recognition memory in rats during early memory formation and memory maintenance. ZIP infusion in either hippocampus or mPFC impaired memory maintenance. However, early memory formation was impaired by ZIP in mPFC but not hippocampus; and blocking GluR2-dependent removal of AMPA receptors did not affect this impairment caused by ZIP in the mPFC. The findings indicate: (i) a difference in the actions of ZIP in hippocampus and medial prefrontal cortex, and (ii) a GluR2-independent target of ZIP (possibly PKCλ) in the mPFC during early memory formation. PMID:24729442

Developmental Reversals in False Memory: A Review of Data and Theory

ERIC Educational Resources Information Center

Brainerd, C. J.; Reyna V. F.; Ceci, S. J.

2008-01-01

Can susceptibility to false memory and suggestion increase dramatically with age? The authors review the theoretical and empirical literatures on this counterintuitive possibility. Until recently, the well-documented pattern was that susceptibility to memory distortion had been found to decline between early childhood and young adulthood. That…

Epigenetic mechanisms: critical contributors to long-term memory formation.

PubMed

Lubin, Farah D; Gupta, Swati; Parrish, R Ryley; Grissom, Nicola M; Davis, Robin L

2011-12-01

Recent advances in chromatin biology have identified a role for epigenetic mechanisms in the regulation of neuronal gene expression changes, a necessary process for proper synaptic plasticity and memory formation. Experimental evidence for dynamic chromatin remodeling influencing gene transcription in postmitotic neurons grew from initial reports describing posttranslational modifications of histones, including phosphorylation and acetylation occurring in various brain regions during memory consolidation. An accumulation of recent studies, however, has also highlighted the importance of other epigenetic modifications, such as DNA methylation and histone methylation, as playing a role in memory formation. This present review examines learning-induced gene transcription by chromatin remodeling underlying long-lasting changes in neurons, with direct implications for the study of epigenetic mechanisms in long-term memory formation and behavior. Furthermore, the study of epigenetic gene regulation, in conjunction with transcription factor activation, can provide complementary lines of evidence to further understanding transcriptional mechanisms subserving memory storage.

Inhibiting corticosterone synthesis during fear memory formation exacerbates cued fear extinction memory deficits within the single prolonged stress model.

PubMed

Keller, Samantha M; Schreiber, William B; Stanfield, Briana R; Knox, Dayan

2015-01-01

Using the single prolonged stress (SPS) animal model of post-traumatic stress disorder (PTSD), previous studies suggest that enhanced glucocorticoid receptor (GR) expression leads to cued fear extinction retention deficits. However, it is unknown how the endogenous ligand of GRs, corticosterone (CORT), may contribute to extinction retention deficits in the SPS model. Given that CORT synthesis during fear learning is critical for fear memory consolidation and SPS enhances GR expression, CORT synthesis during fear memory formation could strengthen fear memory in SPS rats by enhancing GR activation during fear learning. In turn, this could lead to cued fear extinction retention deficits. We tested the hypothesis that CORT synthesis during fear learning leads to cued fear extinction retention deficits in SPS rats by administering the CORT synthesis inhibitor metyrapone to SPS and control rats prior to fear conditioning, and observed the effect this had on extinction memory. Inhibiting CORT synthesis during fear memory formation in control rats tended to decrease cued freezing, though this effect never reached statistical significance. Contrary to our hypothesis, inhibiting CORT synthesis during fear memory formation disrupted extinction retention in SPS rats. This finding suggests that even though SPS exposure leads to cued fear extinction memory deficits, CORT synthesis during fear memory formation enhances extinction retention in SPS rats. This suggests that stress-induced CORT synthesis in previously stressed rats can be beneficial. Copyright © 2015 Elsevier B.V. All rights reserved.

Genetic Dissection of Aversive Associative Olfactory Learning and Memory in Drosophila Larvae

PubMed Central

Widmann, Annekathrin; Artinger, Marc; Biesinger, Lukas; Boepple, Kathrin; Schlechter, Jana; Selcho, Mareike; Thum, Andreas S.

2016-01-01

Memory formation is a highly complex and dynamic process. It consists of different phases, which depend on various neuronal and molecular mechanisms. In adult Drosophila it was shown that memory formation after aversive Pavlovian conditioning includes—besides other forms—a labile short-term component that consolidates within hours to a longer-lasting memory. Accordingly, memory formation requires the timely controlled action of different neuronal circuits, neurotransmitters, neuromodulators and molecules that were initially identified by classical forward genetic approaches. Compared to adult Drosophila, memory formation was only sporadically analyzed at its larval stage. Here we deconstruct the larval mnemonic organization after aversive olfactory conditioning. We show that after odor-high salt conditioning larvae form two parallel memory phases; a short lasting component that depends on cyclic adenosine 3’5’-monophosphate (cAMP) signaling and synapsin gene function. In addition, we show for the first time for Drosophila larvae an anesthesia resistant component, which relies on radish and bruchpilot gene function, protein kinase C activity, requires presynaptic output of mushroom body Kenyon cells and dopamine function. Given the numerical simplicity of the larval nervous system this work offers a unique prospect for studying memory formation of defined specifications, at full-brain scope with single-cell, and single-synapse resolution. PMID:27768692

Genetic Dissection of Aversive Associative Olfactory Learning and Memory in Drosophila Larvae.

PubMed

Widmann, Annekathrin; Artinger, Marc; Biesinger, Lukas; Boepple, Kathrin; Peters, Christina; Schlechter, Jana; Selcho, Mareike; Thum, Andreas S

2016-10-01

Memory formation is a highly complex and dynamic process. It consists of different phases, which depend on various neuronal and molecular mechanisms. In adult Drosophila it was shown that memory formation after aversive Pavlovian conditioning includes-besides other forms-a labile short-term component that consolidates within hours to a longer-lasting memory. Accordingly, memory formation requires the timely controlled action of different neuronal circuits, neurotransmitters, neuromodulators and molecules that were initially identified by classical forward genetic approaches. Compared to adult Drosophila, memory formation was only sporadically analyzed at its larval stage. Here we deconstruct the larval mnemonic organization after aversive olfactory conditioning. We show that after odor-high salt conditioning larvae form two parallel memory phases; a short lasting component that depends on cyclic adenosine 3'5'-monophosphate (cAMP) signaling and synapsin gene function. In addition, we show for the first time for Drosophila larvae an anesthesia resistant component, which relies on radish and bruchpilot gene function, protein kinase C activity, requires presynaptic output of mushroom body Kenyon cells and dopamine function. Given the numerical simplicity of the larval nervous system this work offers a unique prospect for studying memory formation of defined specifications, at full-brain scope with single-cell, and single-synapse resolution.

Disrupting Jagged1-Notch signaling impairs spatial memory formation in adult mice.

PubMed

Sargin, Derya; Botly, Leigh C P; Higgs, Gemma; Marsolais, Alexander; Frankland, Paul W; Egan, Sean E; Josselyn, Sheena A

2013-07-01

It is well-known that Notch signaling plays a critical role in brain development and growing evidence implicates this signaling pathway in adult synaptic plasticity and memory formation. The Notch1 receptor is activated by two subclasses of ligands, Delta-like (including Dll1 and Dll4) and Jagged (including Jag1 and Jag2). Ligand-induced Notch1 receptor signaling is modulated by a family of Fringe proteins, including Lunatic fringe (Lfng). Although Dll1, Jag1 and Lfng are critical regulators of Notch signaling, their relative contribution to memory formation in the adult brain is unknown. To investigate the roles of these important components of Notch signaling in memory formation, we examined spatial and fear memory formation in adult mice with reduced expression of Dll1, Jag1, Lfng and Dll1 plus Lfng. We also examined motor activity, anxiety-like behavior and sensorimotor gating using the acoustic startle response in these mice. Of the lines of mutant mice tested, we found that only mice with reduced Jag1 expression (mice heterozygous for a null mutation in Jag1, Jag1(+/-)) showed a selective impairment in spatial memory formation. Importantly, all other behavior including open field activity, conditioned fear memory (both context and discrete cue), acoustic startle response and prepulse inhibition, was normal in this line of mice. These results provide the first in vivo evidence that Jag1-Notch signaling is critical for memory formation in the adult brain. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Dopaminergic influences on formation of a motor memory.

PubMed

Flöel, Agnes; Breitenstein, Caterina; Hummel, Friedhelm; Celnik, Pablo; Gingert, Christian; Sawaki, Lumy; Knecht, Stefan; Cohen, Leonardo G

2005-07-01

The ability of the central nervous system to form motor memories, a process contributing to motor learning and skill acquisition, decreases with age. Dopaminergic activity, one of the mechanisms implicated in memory formation, experiences a similar decline with aging. It is possible that restoring dopaminergic function in elderly adults could lead to improved formation of motor memories with training. We studied the influence of a single oral dose of levodopa (100mg) administered preceding training on the ability to encode an elementary motor memory in the primary motor cortex of elderly and young healthy volunteers in a randomized, double-blind, placebo-controlled design. Attention to the task and motor training kinematics were comparable across age groups and sessions. In young subjects, encoding a motor memory under placebo was more prominent than in older subjects, and the encoding process was accelerated by intake of levodopa. In the elderly group, diminished motor memory encoding under placebo was enhanced by intake of levodopa to levels present in younger subjects. Therefore, upregulation of dopaminergic activity accelerated memory formation in young subjects and restored the ability to form a motor memory in elderly subjects; possible mechanisms underlying the beneficial effects of dopaminergic agents on motor learning in neurorehabilitation.

Are the memories of older adults positively biased?

PubMed

Fernandes, Myra; Ross, Michael; Wiegand, Melanie; Schryer, Emily

2008-06-01

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

Confabulation behavior and false memories in Korsakoff's syndrome: role of source memory and executive functioning.

PubMed

Kessels, Roy P C; Kortrijk, Hans E; Wester, Arie J; Nys, Gudrun M S

2008-04-01

Confabulation behavior is common in patients with Korsakoff's syndrome. A distinction can be made between spontaneous and provoked confabulations, which may have different underlying cognitive mechanisms. Provoked confabulations may be related to intrusions on memory tests, whereas spontaneous confabulations may be due to executive dysfunction or a source memory deficit. In 19 chronic Korsakoff patients, spontaneous confabulations were quantified by third-party rating (Likert scale). Provoked confabulations were assessed using the Dalla Barba Confabulation Battery. Furthermore, assessment of executive function was performed using an extensive neuropsychological battery. False memories (i.e. intrusions) and source memory were measured using twoparallelversions of a word-list learning paradigm (a modification of the Rey Auditory Verbal Learning Test). There were deficits in source memory, in which patients incorrectly assigned previously learned words to an incorrect word list. Also, Korsakoff patients had extensive executive deficits, but no relationship between the severity of these deficits and the severity of confabulation or intrusions on a memory task was found. The present findings provide evidence for a dissociation between spontaneous confabulation, provoked confabulation and false memories.

Telling true from false: cannabis users show increased susceptibility to false memories.

PubMed

Riba, J; Valle, M; Sampedro, F; Rodríguez-Pujadas, A; Martínez-Horta, S; Kulisevsky, J; Rodríguez-Fornells, A

2015-06-01

Previous studies on the neurocognitive impact of cannabis use have found working and declarative memory deficits that tend to normalize with abstinence. An unexplored aspect of cognitive function in chronic cannabis users is the ability to distinguish between veridical and illusory memories, a crucial aspect of reality monitoring that relies on adequate memory function and cognitive control. Using functional magnetic resonance imaging, we show that abstinent cannabis users have an increased susceptibility to false memories, failing to identify lure stimuli as events that never occurred. In addition to impaired performance, cannabis users display reduced activation in areas associated with memory processing within the lateral and medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring. Furthermore, cannabis consumption was inversely correlated with MTL activity, suggesting that the drug is especially detrimental to the episodic aspects of memory. These findings indicate that cannabis users have an increased susceptibility to memory distortions even when abstinent and drug-free, suggesting a long-lasting compromise of memory and cognitive control mechanisms involved in reality monitoring.

The fallibility of memory in judicial processes: lessons from the past and their modern consequences.

PubMed

Howe, Mark L; Knott, Lauren M

2015-01-01

The capability of adult and child witnesses to accurately recollect events from the past and provide reliable testimony has been hotly debated for more than 100 years. Prominent legal cases of the 1980s and 1990s sparked lengthy debates and important research questions surrounding the fallibility and general reliability of memory. But what lessons have we learned, some 35 years later, about the role of memory in the judicial system? In this review, we focus on what we now know about the consequences of the fallibility of memory for legal proceedings. We present a brief historical overview of false memories that focuses on three critical forensic areas that changed memory research: children as eyewitnesses, historic sexual abuse and eyewitness (mis)identification. We revisit some of the prominent trials of the 1980s and 1990s to not only consider the role false memories have played in judicial decisions, but also to see how this has helped us understand memory today. Finally, we consider the way in which the research on memory (true and false) has been successfully integrated into some courtroom procedures.

Memory formation during anaesthesia: plausibility of a neurophysiological basis

PubMed Central

Veselis, R. A.

2015-01-01

As opposed to conscious, personally relevant (explicit) memories that we can recall at will, implicit (unconscious) memories are prototypical of ‘hidden’ memory; memories that exist, but that we do not know we possess. Nevertheless, our behaviour can be affected by these memories; in fact, these memories allow us to function in an ever-changing world. It is still unclear from behavioural studies whether similar memories can be formed during anaesthesia. Thus, a relevant question is whether implicit memory formation is a realistic possibility during anaesthesia, considering the underlying neurophysiology. A different conceptualization of memory taxonomy is presented, the serial parallel independent model of Tulving, which focuses on dynamic information processing with interactions among different memory systems rather than static classification of different types of memories. The neurophysiological basis for subliminal information processing is considered in the context of brain function as embodied in network interactions. Function of sensory cortices and thalamic activity during anaesthesia are reviewed. The role of sensory and perisensory cortices, in particular the auditory cortex, in support of memory function is discussed. Although improbable, with the current knowledge of neurophysiology one cannot rule out the possibility of memory formation during anaesthesia. PMID:25735711

Cognitive mechanisms of false facial recognition in older adults.

PubMed

Edmonds, Emily C; Glisky, Elizabeth L; Bartlett, James C; Rapcsak, Steven Z

2012-03-01

Older adults show elevated false alarm rates on recognition memory tests involving faces in comparison to younger adults. It has been proposed that this age-related increase in false facial recognition reflects a deficit in recollection and a corresponding increase in the use of familiarity when making memory decisions. To test this hypothesis, we examined the performance of 40 older adults and 40 younger adults on a face recognition memory paradigm involving three different types of lures with varying levels of familiarity. A robust age effect was found, with older adults demonstrating a markedly heightened false alarm rate in comparison to younger adults for "familiarized lures" that were exact repetitions of faces encountered earlier in the experiment, but outside the study list, and therefore required accurate recollection of contextual information to reject. By contrast, there were no age differences in false alarms to "conjunction lures" that recombined parts of study list faces, or to entirely new faces. Overall, the pattern of false recognition errors observed in older adults was consistent with excessive reliance on a familiarity-based response strategy. Specifically, in the absence of recollection older adults appeared to base their memory decisions on item familiarity, as evidenced by a linear increase in false alarm rates with increasing familiarity of the lures. These findings support the notion that automatic memory processes such as familiarity remain invariant with age, while more controlled memory processes such as recollection show age-related decline.

Learning at different satiation levels reveals parallel functions for the cAMP-protein kinase A cascade in formation of long-term memory.

PubMed

Friedrich, Anke; Thomas, Ulf; Müller, Uli

2004-05-05

Learning and memory formation in intact animals is generally studied under defined parameters, including the control of feeding. We used associative olfactory conditioning of the proboscis extension response in honeybees to address effects of feeding status on processes of learning and memory formation. Comparing groups of animals with different but defined feeding status at the time of conditioning reveals new and characteristic features in memory formation. In animals fed 18 hr earlier, three-trial conditioning induces a stable memory that consists of different phases: a mid-term memory (MTM), translation-dependent early long-term memory (eLTM; 1-2 d), and a transcription-dependent late LTM (lLTM; > or =3 d). Additional feeding of a small amount of sucrose 4 hr before conditioning leads to a loss of all of these memory phases. Interestingly, the basal activity of the cAMP-dependent protein kinase A (PKA), a key player in LTM formation, differs in animals with different satiation levels. Pharmacological rescue of the low basal PKA activity in animals fed 4 hr before conditioning points to a specific function of cAMP-PKA cascade in mediating satiation-dependent memory formation. An increase in PKA activity during conditioning rescues only transcription-dependent lLTM; acquisition, MTM, and eLTM are still impaired. Thus, during conditioning, the cAMP-PKA cascade mediates the induction of the transcription-dependent lLTM, depending on the satiation level. This result provides the first evidence for a central and distinct function of the cAMP-PKA cascade connecting satiation level with learning.

Discrete emotion-congruent false memories in the DRM paradigm.

PubMed

Bland, Cassandra E; Howe, Mark L; Knott, Lauren

2016-08-01

Research has shown that false-memory production is enhanced for material that is emotionally congruent with the mood of the participant at the time of encoding. So far this research has only been conducted to examine the influence of generic negative affective mood states and generic negative stimuli on false-memory production. In addition, much of the research is limited as it focuses on valence and arousal dimensions, and fails to take into account the more comprehensive nature of emotions. The current study demonstrates that this effect goes beyond general negative or positive moods and acts at a more discrete emotional level. Participants underwent a standard emotion-induction procedure before listening to negative emotional or neutral associative word lists. The emotions induced, negative word lists, and associated nonpresented critical lures, were related to either fear or anger, 2 negative valence emotions that are also both high in arousal. Results showed that when valence and arousal are controlled for, false memories are more likely to be produced for discrete emotionally congruent compared with incongruent materials. These results support spreading activation theories of false remembering and add to our understanding of the adaptive nature of false-memory production. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Emotion and false memory: How goal-irrelevance can be relevant for what people remember.

PubMed

Van Damme, Ilse; Kaplan, Robin L; Levine, Linda J; Loftus, Elizabeth F

2017-02-01

Elaborating on misleading information concerning emotional events can lead people to form false memories. The present experiment compared participants' susceptibility to false memories when they elaborated on information associated with positive versus negative emotion and pregoal versus postgoal emotion. Pregoal emotion reflects appraisals that goal attainment or failure is anticipated but has not yet occurred (e.g., hope and fear). Postgoal emotion reflects appraisals that goal attainment or failure has already occurred (e.g., happiness and devastation). Participants watched a slideshow depicting an interaction between a couple and were asked to empathise with the protagonist's feelings of hope (positive pregoal), happiness (positive postgoal), fear (negative pregoal), or devastation (negative postgoal); in control conditions, no emotion was mentioned. Participants were then asked to reflect on details of the interaction that had occurred (true) or had not occurred (false), and that were relevant or irrelevant to the protagonist's goal. Irrespective of emotional valence, participants in the pregoal conditions were more susceptible to false memories concerning goal-irrelevant details than were participants in the other conditions. These findings support the view that pregoal emotions narrow attention to information relevant to goal pursuit, increasing susceptibility to false memories for irrelevant information.

Neuroanatomical substrates involved in unrelated false facial recognition.

PubMed

Ronzon-Gonzalez, Eliane; Hernandez-Castillo, Carlos R; Pasaye, Erick H; Vaca-Palomares, Israel; Fernandez-Ruiz, Juan

2017-11-22

Identifying faces is a process central for social interaction and a relevant factor in eyewitness theory. False recognition is a critical mistake during an eyewitness's identification scenario because it can lead to a wrongful conviction. Previous studies have described neural areas related to false facial recognition using the standard Deese/Roediger-McDermott (DRM) paradigm, triggering related false recognition. Nonetheless, misidentification of faces without trying to elicit false memories (unrelated false recognition) in a police lineup could involve different cognitive processes, and distinct neural areas. To delve into the neural circuitry of unrelated false recognition, we evaluated the memory and response confidence of participants while watching faces photographs in an fMRI task. Functional activations of unrelated false recognition were identified by contrasting the activation on this condition vs. the activations related to recognition (hits) and correct rejections. The results identified the right precentral and cingulate gyri as areas with distinctive activations during false recognition events suggesting a conflict resulting in a dysfunction during memory retrieval. High confidence suggested that about 50% of misidentifications may be related to an unconscious process. These findings add to our understanding of the construction of facial memories and its biological basis, and the fallibility of the eyewitness testimony.

Revisiting the rise and fall of false recall: presentation rate effects depend on retention interval.

PubMed

Smith, Troy A; Kimball, Daniel R

2012-01-01

Leading theories of false memory predict that veridical and false recall of lists of semantically associated words can be dissociated by varying the presentation speed during study. Specifically, as presentation rate increases from milliseconds to seconds, veridical recall is predicted to increase monotonically while false recall is predicted to show a rapid rise and then a slow decrease--a pattern shown by McDermott and Watson (2001) in a study using immediate recall tests. In three experiments we tested the generality of the effects of rapid presentation rates on veridical and false memory. In Experiments 1 and 2 participants exhibited high levels of false recall on a delayed recall test, even for very fast stimulus onset asynchronies (SOA)--contrary to predictions from leading theories of false memory. When we switched to an immediate recall test in Experiment 3 we replicated the pattern predicted by the theories and observed by McDermott and Watson. Follow-up analyses further showed that the relative output position of false recalls is not affected by presentation rate, contrary to predictions from fuzzy trace theory. Implications for theories of false memory, including activation monitoring theory and fuzzy trace theory, are discussed.

Memory formation orchestrates the wiring of adult-born hippocampal neurons into brain circuits.

PubMed

Petsophonsakul, Petnoi; Richetin, Kevin; Andraini, Trinovita; Roybon, Laurent; Rampon, Claire

2017-08-01

During memory formation, structural rearrangements of dendritic spines provide a mean to durably modulate synaptic connectivity within neuronal networks. New neurons generated throughout the adult life in the dentate gyrus of the hippocampus contribute to learning and memory. As these neurons become incorporated into the network, they generate huge numbers of new connections that modify hippocampal circuitry and functioning. However, it is yet unclear as to how the dynamic process of memory formation influences their synaptic integration into neuronal circuits. New memories are established according to a multistep process during which new information is first acquired and then consolidated to form a stable memory trace. Upon recall, memory is transiently destabilized and vulnerable to modification. Using contextual fear conditioning, we found that learning was associated with an acceleration of dendritic spines formation of adult-born neurons, and that spine connectivity becomes strengthened after memory consolidation. Moreover, we observed that afferent connectivity onto adult-born neurons is enhanced after memory retrieval, while extinction training induces a change of spine shapes. Together, these findings reveal that the neuronal activity supporting memory processes strongly influences the structural dendritic integration of adult-born neurons into pre-existing neuronal circuits. Such change of afferent connectivity is likely to impact the overall wiring of hippocampal network, and consequently, to regulate hippocampal function.

Effect of ablated hippocampal neurogenesis on the formation and extinction of contextual fear memory

PubMed Central

Ko, Hyoung-Gon; Jang, Deok-Jin; Son, Junehee; Kwak, Chuljung; Choi, Jun-Hyeok; Ji, Young-Hoon; Lee, Yun-Sil; Son, Hyeon; Kaang, Bong-Kiun

2009-01-01

Newborn neurons in the subgranular zone (SGZ) of the hippocampus incorporate into the dentate gyrus and mature. Numerous studies have focused on hippocampal neurogenesis because of its importance in learning and memory. However, it is largely unknown whether hippocampal neurogenesis is involved in memory extinction per se. Here, we sought to examine the possibility that hippocampal neurogenesis may play a critical role in the formation and extinction of hippocampus-dependent contextual fear memory. By methylazoxymethanol acetate (MAM) or gamma-ray irradiation, hippocampal neurogenesis was impaired in adult mice. Under our experimental conditions, only a severe impairment of hippocampal neurogenesis inhibited the formation of contextual fear memory. However, the extinction of contextual fear memory was not affected. These results suggest that although adult newborn neurons contribute to contextual fear memory, they may not be involved in the extinction or erasure of hippocampus-dependent contextual fear memory. PMID:19138433

Epigenetic mechanisms in fear conditioning: Implications for treating post-traumatic stress disorder

PubMed Central

Kwapis, Janine L.; Wood, Marcelo A.

2014-01-01

Post-traumatic stress disorder (PTSD) and other anxiety disorders stemming from dysregulated fear memory are problematic and costly. Understanding the molecular mechanisms that contribute to the formation and maintenance of these persistent fear associations is critical to developing treatments for PTSD. Epigenetic mechanisms, which control gene expression to produce long-lasting changes in cellular function, may support the formation of fear memory underlying PTSD. Here, we address the role of epigenetic mechanisms in the formation, storage, updating, and extinction of fear memories and discuss methods of targeting these epigenetic mechanisms to reduce the initial formation of fear memory or to enhance its extinction. Epigenetic mechanisms may provide a novel target for pharmaceutical and other treatments to reduce aversive memory contributing to PTSD. PMID:25220045

Misremembering What You See or Hear: Dissociable Effects of Modality on Short- and Long-Term False Recognition

ERIC Educational Resources Information Center

Olszewska, Justyna M.; Reuter-Lorenz, Patricia A.; Munier, Emily; Bendler, Sara A.

2015-01-01

False working memories readily emerge using a visual item-recognition variant of the converging associates task. Two experiments, manipulating study and test modality, extended prior working memory results by demonstrating a reliable false recognition effect (more false alarms to associatively related lures than to unrelated lures) within seconds…

Memory and law: what can cognitive neuroscience contribute?

PubMed

Schacter, Daniel L; Loftus, Elizabeth F

2013-02-01

A recent decision in the United States by the New Jersey Supreme Court has led to improved jury instructions that incorporate psychological research showing that memory does not operate like a video recording. Here we consider how cognitive neuroscience could contribute to addressing memory in the courtroom. We discuss conditions in which neuroimaging can distinguish true and false memories in the laboratory and note reasons to be skeptical about its use in courtroom cases. We also discuss neuroscience research concerning false and imagined memories, misinformation effects and reconsolidation phenomena that may enhance understanding of why memory does not operate like a video recording.

“Queasy does it”: False alcohol beliefs and memories may lead to diminished alcohol preferences

PubMed Central

Clifasefi, Seema L.; Bernstein, Daniel M.; Mantonakis, Antonia; Loftus, Elizabeth F.

2013-01-01

Studies have shown that false memories can be implanted via innocuous suggestions, and that these memories can play a role in shaping people’s subsequent attitudes and preferences. The current study explored whether participants (N=147) who received a false suggestion that they had become ill drinking a particular type of alcohol would increase their confidence that the event had occurred, and whether their new-found belief would subsequently affect their alcohol preferences. Results indicated that participants who received a suggestion that they had gotten sick drinking rum or vodka before the age of 16 reported increased confidence that the suggested experience had occurred. Moreover, participants who received a false alcohol suggestion also showed a strong trend to report diminished preference for the specified type of alcohol after the false suggestion. Implantation of a false memory related to one’s past drinking experiences may influence current drink preferences and could be an important avenue for further exploration in the development of alcohol interventions. PMID:23500110

Intra-Amygdala Injections of CREB Antisense Impair Inhibitory Avoidance Memory: Role of Norepinephrine and Acetylcholine

ERIC Educational Resources Information Center

Canal, Clinton E.; Chang, Qing; Gold, Paul E.

2008-01-01

Infusions of CREB antisense into the amygdala prior to training impair memory for aversive tasks, suggesting that the antisense may interfere with CRE-mediated gene transcription and protein synthesis important for the formation of new memories within the amygdala. However, the amygdala also appears to modulate memory formation in distributed…

When true memory availability promotes false memory: evidence from confabulating patients.

PubMed

Ciaramelli, Elisa; Ghetti, Simona; Frattarelli, Massimo; Làdavas, Elisabetta

2006-01-01

We explored the extent to which confabulators are susceptible to false recall and false recognition, and whether false recognition is reduced when memory for studied items is experimentally enhanced. Five confabulating patients, nine non-confabulating amnesics--including patients with (F amnesics) and without frontal-lobe dysfunction (NF amnesics)--and 14 control subjects underwent the DRM paradigm [Roediger, H. L., & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory and Cognition, 21, 803-814.] in two experimental conditions. In both conditions participants studied eight lists of semantic associates, and free recall was tested after the presentation of each list. In the Standard condition recognition was tested after the presentation of all the lists, whereas in the Proximal condition patients were administered a six-item recognition task after the presentation of each list. Participants also provided remember or know judgements, and described the content of their recollections. All groups of patients recalled a lower proportion of targets and critical lures than did control subjects, but confabulators recalled more words unrelated to the studied lists than did NF amnesics and controls. All groups of participants improved true recognition across conditions. However, whereas normal controls suppressed false recognition to critical lures in the Proximal compared to the Standard condition, and non-confabulating amnesics showed comparable gist-based false recognition, confabulators showed increased levels of false recognition to critical lures across conditions. Furthermore, NF amnesics significantly reduced false recognition to unrelated lures in the Proximal compared to the Standard condition, whereas confabulators were unable to suppress false recognition to unrelated lures across conditions. Analysis of the phenomenological experience showed that, unlike non-confabulating amnesics, confabulators characterized true and false memories with irrelevant information related to test items. Results are interpreted in light of confabulators' monitoring deficits.

An individual differences approach to the suggestibility of memory over time.

PubMed

Frost, Peter; Nussbaum, Gregory; Loconto, Taylor; Syke, Richard; Warren, Casey; Muise, Christina

2013-04-01

We examined how certain personality traits might relate to the formation of suggestive memory over time. We hypothesised that compliance and trust relate to initial acceptance of misinformation as memory, whereas fantasy proneness might relate to integration of misinformation into memory after later intervals (relative to the time of exposure to misinformation). Participants watched an excerpt from a movie--the simulated eyewitness event. They next answered a recall test that included embedded misinformation about the movie. Participants then answered a yes/no recognition test. A week later, participants answered a second yes/no recognition test about the movie (each yes/no recognition test included different questions). Before both recognition tests, participants were warned about the misinformation shown during recall and were asked to base their answer on the movie excerpt only. After completing the second recognition test, participants answered questions from the Neuroticism Extroversion Openness Personality Inventory-3 (McCrae, Costa, & Martin, 2005) and Creative Experiences Questionnaire (Merckelbach, Horselenberg, & Muris, 2001). While compliance correlated with misinformation effects immediately after exposure to misinformation, fantasy-prone personality accounted for more of the variability in false recognition rates than compliance after a 1-week interval.

RNG105/caprin1, an RNA granule protein for dendritic mRNA localization, is essential for long-term memory formation.

PubMed

Nakayama, Kei; Ohashi, Rie; Shinoda, Yo; Yamazaki, Maya; Abe, Manabu; Fujikawa, Akihiro; Shigenobu, Shuji; Futatsugi, Akira; Noda, Masaharu; Mikoshiba, Katsuhiko; Furuichi, Teiichi; Sakimura, Kenji; Shiina, Nobuyuki

2017-11-21

Local regulation of synaptic efficacy is thought to be important for proper networking of neurons and memory formation. Dysregulation of global translation influences long-term memory in mice, but the relevance of the regulation specific for local translation by RNA granules remains elusive. Here, we demonstrate roles of RNG105/caprin1 in long-term memory formation. RNG105 deletion in mice impaired synaptic strength and structural plasticity in hippocampal neurons. Furthermore, RNG105-deficient mice displayed unprecedentedly severe defects in long-term memory formation in spatial and contextual learning tasks. Genome-wide profiling of mRNA distribution in the hippocampus revealed an underlying mechanism: RNG105 deficiency impaired the asymmetric somato-dendritic localization of mRNAs. Particularly, RNG105 deficiency reduced the dendritic localization of mRNAs encoding regulators of AMPAR surface expression, which was consistent with attenuated homeostatic AMPAR scaling in dendrites and reduced synaptic strength. Thus, RNG105 has an essential role, as a key regulator of dendritic mRNA localization, in long-term memory formation.

Semantic False Memories in the Form of Derived Relational Intrusions Following Training

ERIC Educational Resources Information Center

Guinther, Paul M.; Dougher, Michael J.

2010-01-01

Contemporary behavior analytic research is making headway in characterizing memory phenomena that typically have been characterized by cognitive models, and the current study extends this development by producing "false memories" in the form of functional equivalence responding. A match-to-sample training procedure was administered in order to…

Experimentally Evoking Nonbelieved Memories for Childhood Events

ERIC Educational Resources Information Center

Otgaar, Henry; Scoboria, Alan; Smeets, Tom

2013-01-01

We report on the 1st experimental elicitation of nonbelieved memories for childhood events in adults (Study 1) and children (Study 2) using a modified false memory implantation paradigm. Participants received true (trip to a theme park) and false (hot air balloon ride) narratives and recalled these events during 2 interviews. After debriefing, 13%…

Individual Differences in Susceptibility to False Memory in the Deese-Roediger-McDermott Paradigm

ERIC Educational Resources Information Center

Watson, Jason M.; Bunting, Michael F.; Poole, Bradley J.; Conway, Andrew R. A.

2005-01-01

The authors addressed whether individual differences in the working memory capacity (WMC) of young adults influence susceptibility to false memories for nonpresented critical words in the Deese-Roediger-McDermott associative list paradigm. The results of 2 experiments indicated that individuals with greater WMC recalled fewer critical words than…

The power of emotion versus the power of suggestion: memory for emotional events in the misinformation paradigm.

PubMed

Van Damme, Ilse; Smets, Karolien

2014-04-01

Research has shown that emotional events are remembered better than neutral events, but might also elicit an increase in false memories. The present study was designed to disentangle the influences of valence and arousal on event memory in the misinformation paradigm. Participants were shown six types of photographs (positive with high/low arousal, negative with high/low arousal, ambiguous, neutral), after which half of them were exposed to misleading information. A recognition test assessed memory for both correct and false central and peripheral details. Negative and ambiguous events elicited fewer correct and more false memories for peripheral details than positive and neutral events, regardless of previous exposure to misinformation. Arousal improved memory for correct central details, and both negative valence and arousal inhibited control participants' tendency to endorse false central details. The power of emotion was overruled by the power of suggestion, however, as the latter effect disappeared with previous exposure to misinformation. Results are discussed in the light of earlier research on emotion and cognition, recent motivational theories, and implications for forensic practice.

Intellectual factors in false memories of patients with schizophrenia.

PubMed

Zhu, Bi; Chen, Chuansheng; Loftus, Elizabeth F; Dong, Qi; Lin, Chongde; Li, Jun

2018-07-01

The current study explored the intellectual factors in false memories of 139 patients with schizophrenia, using a recognition task and an IQ test. The full-scale IQ score of the participants ranged from 57 to 144 (M = 100, SD = 14). The full IQ score had a negative correlation with false recognition in patients with schizophrenia, and positive correlations with high-confidence true recognition and discrimination rates. Further analyses with the subtests' scores revealed that false recognition was negatively correlated with scores of performance IQ (and one of its subtests: picture arrangement), whereas true recognition was positively correlated with scores of verbal IQ (and two of its subtests: information and digit span). High-IQ patients had less false recognition (overall or high-confidence false recognition), more high-confidence true recognition, and higher discrimination abilities than those with low IQ. These findings contribute to a better understanding of the cognitive mechanism in false memory of patients with schizophrenia, and are of practical relevance to the evaluation of memory reliability in patients with different intellectual levels. Copyright © 2018 Elsevier B.V. All rights reserved.

Conscious and unconscious discriminations between true and false memories.

PubMed

Jou, Jerwen

2011-09-01

When subjects give higher confidence or memory ratings to a test word in a recognition test, do they simply raise their criterion without making better discrimination, or do they raise both criterion and true discrimination between the studied words (SW) and the lures? Given that previous studies found subjects' false alarm responses to lures slower than to SW, and recognition latency inversely correlated with the confidence rating, can the latency difference between the lures and SW be accounted for by confidence or memory ratings? The present results showed that when subjects gave higher confidence or memory ratings, both their bias and sensitivity were raised, indicating that they could consciously distinguish the lures from the SW. However, a latency difference between true and false recognitions persisted after confidence and memory ratings were held constant, suggesting an unconscious source of discrimination between the two types of memory. Published by Elsevier Inc.

Inferential false memories of events: negative consequences protect from distortions when the events are free from further elaboration.

PubMed

Mirandola, Chiara; Toffalini, Enrico; Grassano, Massimo; Cornoldi, Cesare; Melinder, Annika

2014-01-01

The present experiment was conducted to investigate whether negative emotionally charged and arousing content of to-be-remembered scripted material would affect propensity towards memory distortions. We further investigated whether elaboration of the studied material through free recall would affect the magnitude of memory errors. In this study participants saw eight scripts. Each of the scripts included an effect of an action, the cause of which was not presented. Effects were either negatively emotional or neutral. Participants were assigned to either a yes/no recognition test group (recognition), or to a recall and yes/no recognition test group (elaboration + recognition). Results showed that participants in the recognition group produced fewer memory errors in the emotional condition. Conversely, elaboration + recognition participants had lower accuracy and produced more emotional memory errors than the other group, suggesting a mediating role of semantic elaboration on the generation of false memories. The role of emotions and semantic elaboration on the generation of false memories is discussed.

The Naïve and the Distrustful: state dependency of hippocampal computations in manipulative memory distortion.

PubMed

Ludmer, Rachel; Edelson, Micah G; Dudai, Yadin

2015-02-01

Flexible mnemonic mechanisms that adjust to different internal mental states can provide a major adaptive advantage. However, little is known regarding how this flexibility is achieved in the human brain. We examined brain activity during retrieval of false memories of a movie, generated by exposing participants to misleading information. Half of the participants suspected the memory manipulation (Distrustful), whereas the other half did not (Naïve). Distrustful displayed more accurate memory performance and a brain signature different than that of Naïve. In Distrustful, the ability to differentiate true from false information was driven by a qualitatively distinct hippocampal activity for endorsed items, consistent with the view that hippocampal encoding allows recollection of a specific source. Conversely, in Naïve, BOLD differences between true and false memories were linearly correlated with accuracy across participants, suggesting that Naïve subjects needed to reinstate and evaluate stored information to discern true from false. We propose that our results lend support to models suggesting that hippocampal activity can exhibit different computational schemes, depending on memorandum attributes. Furthermore, we show that trust, considered as a subjective state of mind, may alter basic hippocampal strategies, influencing the ability to separate real from false memory. © 2014 Wiley Periodicals, Inc.

NF-κB mediates Gadd45β expression and DNA demethylation in the hippocampus during fear memory formation.

PubMed

Jarome, Timothy J; Butler, Anderson A; Nichols, Jessica N; Pacheco, Natasha L; Lubin, Farah D

2015-01-01

Gadd45-mediated DNA demethylation mechanisms have been implicated in the process of memory formation. However, the transcriptional mechanisms involved in the regulation of Gadd45 gene expression during memory formation remain unexplored. NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) controls transcription of genes in neurons and is a critical regulator of synaptic plasticity and memory formation. In silico analysis revealed several NF-κB (p65/RelA and cRel) consensus sequences within the Gadd45β gene promoter. Whether NF-κB activity regulates Gadd45 expression and associated DNA demethylation in neurons during memory formation is unknown. Here, we found that learning in a fear conditioning paradigm increased Gadd45β gene expression and brain-derivedneurotrophic factor (BDNF) DNA demethylation in area CA1 of the hippocampus, both of which were prevented with pharmacological inhibition of NF-κB activity. Further experiments found that conditional mutations in p65/RelA impaired fear memory formation but did not alter changes in Gadd45β expression. The learning-induced increases in Gadd45β mRNA levels, Gadd45β binding at the BDNF gene and BDNF DNA demethylation were blocked in area CA1 of the c-rel knockout mice. Additionally, local siRNA-mediated knockdown of c-rel in area CA1 prevented fear conditioning-induced increases in Gadd45β expression and BDNF DNA demethylation, suggesting that c-Rel containing NF-κB transcription factor complex is responsible for Gadd45β regulation during memory formation. Together, these results support a novel transcriptional role for NF-κB in regulation of Gadd45β expression and DNA demethylation in hippocampal neurons during fear memory.

The differential role of cortical protein synthesis in taste memory formation and persistence

NASA Astrophysics Data System (ADS)

Levitan, David; Gal-Ben-Ari, Shunit; Heise, Christopher; Rosenberg, Tali; Elkobi, Alina; Inberg, Sharon; Sala, Carlo; Rosenblum, Kobi

2016-05-01

The current dogma suggests that the formation of long-term memory (LTM) is dependent on protein synthesis but persistence of the memory trace is not. However, many of the studies examining the effect of protein synthesis inhibitors (PSIs) on LTM persistence were performed in the hippocampus, which is known to have a time-dependent role in memory storage, rather than the cortex, which is considered to be the main structure to store long-term memories. Here we studied the effect of PSIs on LTM formation and persistence in male Wistar Hola (n⩾5) rats by infusing the protein synthesis inhibitor, anisomycin (100 μg, 1 μl), into the gustatory cortex (GC) during LTM formation and persistence in conditioned taste aversion (CTA). We found that local anisomycin infusion to the GC before memory acquisition impaired LTM formation (P=8.9E-5), but had no effect on LTM persistence when infused 3 days post acquisition (P=0.94). However, when we extended the time interval between treatment with anisomycin and testing from 3 days to 14 days, LTM persistence was enhanced (P=0.01). The enhancement was on the background of stable and non-declining memory, and was not recapitulated by another amnesic agent, APV (10 μg, 1 μl), an N-methyl-D-aspartate receptor antagonist (P=0.54). In conclusion, CTA LTM remains sensitive to the action of PSIs in the GC even 3 days following memory acquisition. This sensitivity is differentially expressed between the formation and persistence of LTM, suggesting that increased cortical protein synthesis promotes LTM formation, whereas decreased protein synthesis promotes LTM persistence.

Pre-stimulus thalamic theta power predicts human memory formation.

PubMed

Sweeney-Reed, Catherine M; Zaehle, Tino; Voges, Jürgen; Schmitt, Friedhelm C; Buentjen, Lars; Kopitzki, Klaus; Richardson-Klavehn, Alan; Hinrichs, Hermann; Heinze, Hans-Jochen; Knight, Robert T; Rugg, Michael D

2016-09-01

Pre-stimulus theta (4-8Hz) power in the hippocampus and neocortex predicts whether a memory for a subsequent event will be formed. Anatomical studies reveal thalamus-hippocampal connectivity, and lesion, neuroimaging, and electrophysiological studies show that memory processing involves the dorsomedial (DMTN) and anterior thalamic nuclei (ATN). The small size and deep location of these nuclei have limited real-time study of their activity, however, and it is unknown whether pre-stimulus theta power predictive of successful memory formation is also found in these subcortical structures. We recorded human electrophysiological data from the DMTN and ATN of 7 patients receiving deep brain stimulation for refractory epilepsy. We found that greater pre-stimulus theta power in the right DMTN was associated with successful memory encoding, predicting both behavioral outcome and post-stimulus correlates of successful memory formation. In particular, significant correlations were observed between right DMTN theta power and both frontal theta and right ATN gamma (32-50Hz) phase alignment, and frontal-ATN theta-gamma cross-frequency coupling. We draw the following primary conclusions. Our results provide direct electrophysiological evidence in humans of a role for the DMTN as well as the ATN in memory formation. Furthermore, prediction of subsequent memory performance by pre-stimulus thalamic oscillations provides evidence that post-stimulus differences in thalamic activity that index successful and unsuccessful encoding reflect brain processes specifically underpinning memory formation. Finally, the findings broaden the understanding of brain states that facilitate memory encoding to include subcortical as well as cortical structures. Copyright © 2016 Elsevier Inc. All rights reserved.

A Mathematical Model for the Hippocampus: Towards the Understanding of Episodic Memory and Imagination

NASA Astrophysics Data System (ADS)

Tsuda, I.; Yamaguti, Y.; Kuroda, S.; Fukushima, Y.; Tsukada, M.

How does the brain encode episode? Based on the fact that the hippocampus is responsible for the formation of episodic memory, we have proposed a mathematical model for the hippocampus. Because episodic memory includes a time series of events, an underlying dynamics for the formation of episodic memory is considered to employ an association of memories. David Marr correctly pointed out in his theory of archecortex for a simple memory that the hippocampal CA3 is responsible for the formation of associative memories. However, a conventional mathematical model of associative memory simply guarantees a single association of memory unless a rule for an order of successive association of memories is given. The recent clinical studies in Maguire's group for the patients with the hippocampal lesion show that the patients cannot make a new story, because of the lack of ability of imagining new things. Both episodic memory and imagining things include various common characteristics: imagery, the sense of now, retrieval of semantic information, and narrative structures. Taking into account these findings, we propose a mathematical model of the hippocampus in order to understand the common mechanism of episodic memory and imagination.

NR4A nuclear receptors support memory enhancement by histone deacetylase inhibitors

PubMed Central

Hawk, Joshua D.; Bookout, Angie L.; Poplawski, Shane G.; Bridi, Morgan; Rao, Allison J.; Sulewski, Michael E.; Kroener, Brian T.; Manglesdorf, David J.; Abel, Ted

2012-01-01

The formation of a long-lasting memory requires a transcription-dependent consolidation period that converts a short-term memory into a long-term memory. Nuclear receptors compose a class of transcription factors that regulate diverse biological processes, and several nuclear receptors have been implicated in memory formation. Here, we examined the potential contribution of nuclear receptors to memory consolidation by measuring the expression of all 49 murine nuclear receptors after learning. We identified 13 nuclear receptors with increased expression after learning, including all 3 members of the Nr4a subfamily. These CREB-regulated Nr4a genes encode ligand-independent “orphan” nuclear receptors. We found that blocking NR4A activity in memory-supporting brain regions impaired long-term memory but did not impact short-term memory in mice. Further, expression of Nr4a genes increased following the memory-enhancing effects of histone deacetylase (HDAC) inhibitors. Blocking NR4A signaling interfered with the ability of HDAC inhibitors to enhance memory. These results demonstrate that the Nr4a gene family contributes to memory formation and is a promising target for improving cognitive function. PMID:22996661

Molecular Mechanisms Underlying Formation of Long-Term Reward Memories and Extinction Memories in the Honeybee ("Apis Mellifera")

ERIC Educational Resources Information Center

Eisenhardt, Dorothea

2014-01-01

The honeybee ("Apis mellifera") has long served as an invertebrate model organism for reward learning and memory research. Its capacity for learning and memory formation is rooted in the ecological need to efficiently collect nectar and pollen during summer to ensure survival of the hive during winter. Foraging bees learn to associate a…

Predicting episodic memory formation for movie events

PubMed Central

Tang, Hanlin; Singer, Jed; Ison, Matias J.; Pivazyan, Gnel; Romaine, Melissa; Frias, Rosa; Meller, Elizabeth; Boulin, Adrianna; Carroll, James; Perron, Victoria; Dowcett, Sarah; Arellano, Marlise; Kreiman, Gabriel

2016-01-01

Episodic memories are long lasting and full of detail, yet imperfect and malleable. We quantitatively evaluated recollection of short audiovisual segments from movies as a proxy to real-life memory formation in 161 subjects at 15 minutes up to a year after encoding. Memories were reproducible within and across individuals, showed the typical decay with time elapsed between encoding and testing, were fallible yet accurate, and were insensitive to low-level stimulus manipulations but sensitive to high-level stimulus properties. Remarkably, memorability was also high for single movie frames, even one year post-encoding. To evaluate what determines the efficacy of long-term memory formation, we developed an extensive set of content annotations that included actions, emotional valence, visual cues and auditory cues. These annotations enabled us to document the content properties that showed a stronger correlation with recognition memory and to build a machine-learning computational model that accounted for episodic memory formation in single events for group averages and individual subjects with an accuracy of up to 80%. These results provide initial steps towards the development of a quantitative computational theory capable of explaining the subjective filtering steps that lead to how humans learn and consolidate memories. PMID:27686330

Mechanisms of Translation Control Underlying Long-lasting Synaptic Plasticity and the Consolidation of Long-term Memory

PubMed Central

Santini, Emanuela; Huynh, Thu N.; Klann, Eric

2018-01-01

The complexity of memory formation and its persistence is a phenomenon that has been studied intensely for centuries. Memory exists in many forms and is stored in various brain regions. Generally speaking, memories are reorganized into broadly distributed cortical networks over time through systems level consolidation. At the cellular level, storage of information is believed to initially occur via altered synaptic strength by processes such as long-term potentiation (LTP). New protein synthesis is required for long-lasting synaptic plasticity as well as for the formation of long-term memory. The mammalian target of rapamycin complex 1 (mTORC1) is a critical regulator of cap-dependent protein synthesis and is required for numerous forms of long-lasting synaptic plasticity and long-term memory. As such, the study of mTORC1 and protein factors that control translation initiation and elongation have enhanced our understanding of how the process of protein synthesis is regulated during memory formation. Herein we will discuss the molecular mechanisms that regulate protein synthesis as well as pharmacological and genetic manipulations that demonstrate the requirement for proper translational control in long-lasting synaptic plasticity and long-term memory formation. PMID:24484700

Predicting episodic memory formation for movie events.

PubMed

Tang, Hanlin; Singer, Jed; Ison, Matias J; Pivazyan, Gnel; Romaine, Melissa; Frias, Rosa; Meller, Elizabeth; Boulin, Adrianna; Carroll, James; Perron, Victoria; Dowcett, Sarah; Arellano, Marlise; Kreiman, Gabriel

2016-09-30

Episodic memories are long lasting and full of detail, yet imperfect and malleable. We quantitatively evaluated recollection of short audiovisual segments from movies as a proxy to real-life memory formation in 161 subjects at 15 minutes up to a year after encoding. Memories were reproducible within and across individuals, showed the typical decay with time elapsed between encoding and testing, were fallible yet accurate, and were insensitive to low-level stimulus manipulations but sensitive to high-level stimulus properties. Remarkably, memorability was also high for single movie frames, even one year post-encoding. To evaluate what determines the efficacy of long-term memory formation, we developed an extensive set of content annotations that included actions, emotional valence, visual cues and auditory cues. These annotations enabled us to document the content properties that showed a stronger correlation with recognition memory and to build a machine-learning computational model that accounted for episodic memory formation in single events for group averages and individual subjects with an accuracy of up to 80%. These results provide initial steps towards the development of a quantitative computational theory capable of explaining the subjective filtering steps that lead to how humans learn and consolidate memories.

Neural mechanisms of reactivation-induced updating that enhance and distort memory

PubMed Central

St. Jacques, Peggy L.; Olm, Christopher; Schacter, Daniel L.

2013-01-01

We remember a considerable number of personal experiences because we are frequently reminded of them, a process known as memory reactivation. Although memory reactivation helps to stabilize and update memories, reactivation may also introduce distortions if novel information becomes incorporated with memory. Here we used functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms mediating reactivation-induced updating in memory for events experienced during a museum tour. During scanning, participants were shown target photographs to reactivate memories from the museum tour followed by a novel lure photograph from an alternate tour. Later, participants were presented with target and lure photographs and asked to determine whether the photographs showed a stop they visited during the tour. We used a subsequent memory analysis to examine neural recruitment during reactivation that was associated with later true and false memories. We predicted that the quality of reactivation, as determined by online ratings of subjective recollection, would increase subsequent true memories but also facilitate incorporation of the lure photograph, thereby increasing subsequent false memories. The fMRI results revealed that the quality of reactivation modulated subsequent true and false memories via recruitment of left posterior parahippocampal, bilateral retrosplenial, and bilateral posterior inferior parietal cortices. However, the timing of neural recruitment and the way in which memories were reactivated contributed to differences in whether memory reactivation led to distortions or not. These data reveal the neural mechanisms recruited during memory reactivation that modify how memories will be subsequently retrieved, supporting the flexible and dynamic aspects of memory. PMID:24191059

Neural mechanisms of reactivation-induced updating that enhance and distort memory.

PubMed

St Jacques, Peggy L; Olm, Christopher; Schacter, Daniel L

2013-12-03

We remember a considerable number of personal experiences because we are frequently reminded of them, a process known as memory reactivation. Although memory reactivation helps to stabilize and update memories, reactivation may also introduce distortions if novel information becomes incorporated with memory. Here we used functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms mediating reactivation-induced updating in memory for events experienced during a museum tour. During scanning, participants were shown target photographs to reactivate memories from the museum tour followed by a novel lure photograph from an alternate tour. Later, participants were presented with target and lure photographs and asked to determine whether the photographs showed a stop they visited during the tour. We used a subsequent memory analysis to examine neural recruitment during reactivation that was associated with later true and false memories. We predicted that the quality of reactivation, as determined by online ratings of subjective recollection, would increase subsequent true memories but also facilitate incorporation of the lure photograph, thereby increasing subsequent false memories. The fMRI results revealed that the quality of reactivation modulated subsequent true and false memories via recruitment of left posterior parahippocampal, bilateral retrosplenial, and bilateral posterior inferior parietal cortices. However, the timing of neural recruitment and the way in which memories were reactivated contributed to differences in whether memory reactivation led to distortions or not. These data reveal the neural mechanisms recruited during memory reactivation that modify how memories will be subsequently retrieved, supporting the flexible and dynamic aspects of memory.

Memory formation during anaesthesia: plausibility of a neurophysiological basis.

PubMed

Veselis, R A

2015-07-01

As opposed to conscious, personally relevant (explicit) memories that we can recall at will, implicit (unconscious) memories are prototypical of 'hidden' memory; memories that exist, but that we do not know we possess. Nevertheless, our behaviour can be affected by these memories; in fact, these memories allow us to function in an ever-changing world. It is still unclear from behavioural studies whether similar memories can be formed during anaesthesia. Thus, a relevant question is whether implicit memory formation is a realistic possibility during anaesthesia, considering the underlying neurophysiology. A different conceptualization of memory taxonomy is presented, the serial parallel independent model of Tulving, which focuses on dynamic information processing with interactions among different memory systems rather than static classification of different types of memories. The neurophysiological basis for subliminal information processing is considered in the context of brain function as embodied in network interactions. Function of sensory cortices and thalamic activity during anaesthesia are reviewed. The role of sensory and perisensory cortices, in particular the auditory cortex, in support of memory function is discussed. Although improbable, with the current knowledge of neurophysiology one cannot rule out the possibility of memory formation during anaesthesia. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Structural Components of Synaptic Plasticity and Memory Consolidation

PubMed Central

Bailey, Craig H.; Kandel, Eric R.; Harris, Kristen M.

2015-01-01

Consolidation of implicit memory in the invertebrate Aplysia and explicit memory in the mammalian hippocampus are associated with remodeling and growth of preexisting synapses and the formation of new synapses. Here, we compare and contrast structural components of the synaptic plasticity that underlies these two distinct forms of memory. In both cases, the structural changes involve time-dependent processes. Thus, some modifications are transient and may contribute to early formative stages of long-term memory, whereas others are more stable, longer lasting, and likely to confer persistence to memory storage. In addition, we explore the possibility that trans-synaptic signaling mechanisms governing de novo synapse formation during development can be reused in the adult for the purposes of structural synaptic plasticity and memory storage. Finally, we discuss how these mechanisms set in motion structural rearrangements that prepare a synapse to strengthen the same memory and, perhaps, to allow it to take part in other memories as a basis for understanding how their anatomical representation results in the enhanced expression and storage of memories in the brain. PMID:26134321

Categorical and associative relations increase false memory relative to purely associative relations.

PubMed

Coane, Jennifer H; McBride, Dawn M; Termonen, Miia-Liisa; Cutting, J Cooper

2016-01-01

The goal of the present study was to examine the contributions of associative strength and similarity in terms of shared features to the production of false memories in the Deese/Roediger-McDermott list-learning paradigm. Whereas the activation/monitoring account suggests that false memories are driven by automatic associative activation from list items to nonpresented lures, combined with errors in source monitoring, other accounts (e.g., fuzzy trace theory, global-matching models) emphasize the importance of semantic-level similarity, and thus predict that shared features between list and lure items will increase false memory. Participants studied lists of nine items related to a nonpresented lure. Half of the lists consisted of items that were associated but did not share features with the lure, and the other half included items that were equally associated but also shared features with the lure (in many cases, these were taxonomically related items). The two types of lists were carefully matched in terms of a variety of lexical and semantic factors, and the same lures were used across list types. In two experiments, false recognition of the critical lures was greater following the study of lists that shared features with the critical lure, suggesting that similarity at a categorical or taxonomic level contributes to false memory above and beyond associative strength. We refer to this phenomenon as a "feature boost" that reflects additive effects of shared meaning and association strength and is generally consistent with accounts of false memory that have emphasized thematic or feature-level similarity among studied and nonstudied representations.

Recall of false memories in individuals scoring high in schizotypy: memory distortions are scale specific.

PubMed

Saunders, Jo; Randell, Jordan; Reed, Phil

2012-06-01

Previous research has indicated abnormal semantic activation in individuals scoring higher in schizotypy. In the current experiment, semantic activation was examined by using the Deese-Roediger-McDermott paradigm of false memories. Participants were assessed for schizotypy using the Oxford-Liverpool Inventory of Feelings (OLIFE). Participants studied lists of semantically related words in which a critical and highly associated word was absent. Participants then recalled the list. Participants high in Unusual Experiences and Cognitive Disorganization recalled more critical non-presented words, weakly related studied words, and fewer studied words than participants who scored low on these measures. Previous research using the cognitive-perceptual factor of the Schizotypy Personality Questionnaire found reduced false memories, while the Unusual Experiences subscale of the OLIFE was associated with more false memories. Both scales cover similar unusual perceptual experiences and it is unclear why they led to divergent results. The findings suggest that subtypes of schizotypy are associated with abnormal semantic activation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Memory loss versus memory distortion: the role of encoding and retrieval deficits in Korsakoff patients' false memories.

PubMed

Van Damme, Ilse; d'Ydewalle, Gery

2009-05-01

Recent studies with the Deese/Roediger-McDermott (DRM) paradigm have revealed that Korsakoff patients show reduced levels of false recognition and different patterns of false recall compared to controls. The present experiment examined whether this could be attributed to an encoding deficit, or rather to problems with explicitly retrieving thematic information at test. In a variation on the DRM paradigm, both patients and controls were presented with associative as well as categorised word lists, with the order of recall and recognition tests manipulated between-subjects. The results point to an important role for the automatic/controlled retrieval distinction: Korsakoff patients' false memory was only diminished compared to controls' when automatic or short-term memory processes could not be used to fulfil the task at hand. Hence, the patients' explicit retrieval deficit appears to be crucial in explaining past and present data. Results are discussed in terms of fuzzy-trace and activation-monitoring theories.

False Memories Lack Perceptual Detail: Evidence from Implicit Word-Stem Completion and Perceptual Identification Tests

ERIC Educational Resources Information Center

Hicks, J.L.; Starns, J.J.

2005-01-01

We used implicit measures of memory to ascertain whether false memories for critical nonpresented items in the DRM paradigm (Deese, 1959; Roediger & McDermott, 1995) contain structural and perceptual detail. In Experiment 1, we manipulated presentation modality in a visual word-stem-completion task. Critical item priming was significant and…

An Associative-Activation Theory of Children's and Adults' Memory Illusions

ERIC Educational Resources Information Center

Howe, Mark L.; Wimmer, Marina C.; Gagnon, Nadine; Plumpton, Shannon

2009-01-01

The effects of associative strength and gist relations on rates of children's and adults' true and false memories were examined in three experiments. Children aged 5-11 and university-aged adults participated in a standard Deese/Roediger-McDermott false memory task using DRM and category lists in two experiments and in the third, children…

Activation of Imaginal Information on True and False Memories

ERIC Educational Resources Information Center

Chang, Sau Hou; Pierce, Benton H.

2009-01-01

The present study examined the activation of imaginal information on true and false memories. Participants studied a series of concrete objects in pictures or words. The imagery group (n = 96) was instructed to form images and the control group (n = 96) was not instructed to do so. Both groups were then given a standard recognition memory test and…

Adaptive Memory: Survival Processing Increases Both True and False Memory in Adults and Children

ERIC Educational Resources Information Center

Otgaar, Henry; Smeets, Tom

2010-01-01

Research has shown that processing information in a survival context can enhance the information's memorability. The current study examined whether survival processing can also decrease the susceptibility to false memories and whether the survival advantage can be found in children. In Experiment 1, adults rated semantically related words in a…

Increased Interhemispheric Interaction Is Associated with Decreased False Memories in a Verbal Converging Semantic Associates Paradigm

ERIC Educational Resources Information Center

Christman, S.D.; Propper, R.E.; Dion, A.

2004-01-01

Recent evidence indicates that task and subject variables that are associated with increased interaction between the left and right cerebral hemispheres result in enhanced performance on tests of episodic memory. The current study looked at the effects of increased interhemispheric interaction on false memories using a verbal converging semantic…

Age differences and format effects in working memory.

PubMed

Foos, Paul W; Goolkasian, Paula

2010-07-01

Format effects refer to lower recall of printed words from working memory when compared to spoken words or pictures. These effects have been attributed to an attenuation of attention to printed words. The present experiment compares younger and older adults' recall of three or six items presented as pictures, spoken words, printed words, and alternating case WoRdS. The latter stimuli have been shown to increase attention to printed words and, thus, reduce format effects. The question of interest was whether these stimuli would also reduce format effects for older adults whose working memory capacity has fewer attentional resources to allocate. Results showed that older adults performed as well as younger adults with three items but less well with six and that format effects were reduced for both age groups, but more for young, when alternating case words were used. Other findings regarding executive control of working memory are discussed. The obtained differences support models of reduced capacity in older adult working memory.

Attention improves memory by suppressing spiking-neuron activity in the human anterior temporal lobe.

PubMed

Wittig, John H; Jang, Anthony I; Cocjin, John B; Inati, Sara K; Zaghloul, Kareem A

2018-06-01

We identify a memory-specific attention mechanism in the human anterior temporal lobe, an area implicated in semantic processing and episodic memory formation. Spiking neuron activity is suppressed and becomes more reliable in preparation for verbal memory formation. Intracranial electroencephalography signals implicate this region as a source of executive control for attentional selection. Consistent with this interpretation, its surgical removal causes significant memory impairment for attended words relative to unattended words.

The Effects of Feedback on Memory Strategies of Younger and Older Adults

PubMed Central

Zhang, Fan; Zhang, Xin; Luo, Meng; Geng, Haiyan

2016-01-01

Existing literature suggests that feedback could effectively reduce false memories in younger adults. However, it is unclear whether memory performance in older adults also might be affected by feedback. The current study tested the hypothesis that older adults can use immediate feedback to adjust their memory strategy, similar to younger adults, but after feedback is removed, older adults may not be able to maintain using the memory strategy. Older adults will display more false memories than younger adults due to a reduction in attentional resources. In Study 1, both younger and older adults adjusted gist processing and item-specific processing biases based on the feedback given (i.e., biased and objective feedback). In Study 2 after the feedback was removed, only younger adults with full attention were able to maintain the feedback-shaped memory strategy; whereas, both younger adults with divided attention and older adults had increased false memories after feedback was removed. The findings suggest that environmental support helps older adults as well as younger adults to adopt a memory strategy that demands high attentional resources, but when the support is removed, older adults can no longer maintain such a strategy. PMID:28033327

The fallibility of memory in judicial processes: Lessons from the past and their modern consequences

PubMed Central

Howe, Mark L.; Knott, Lauren M.

2015-01-01

The capability of adult and child witnesses to accurately recollect events from the past and provide reliable testimony has been hotly debated for more than 100 years. Prominent legal cases of the 1980s and 1990s sparked lengthy debates and important research questions surrounding the fallibility and general reliability of memory. But what lessons have we learned, some 35 years later, about the role of memory in the judicial system? In this review, we focus on what we now know about the consequences of the fallibility of memory for legal proceedings. We present a brief historical overview of false memories that focuses on three critical forensic areas that changed memory research: children as eyewitnesses, historic sexual abuse and eyewitness (mis)identification. We revisit some of the prominent trials of the 1980s and 1990s to not only consider the role false memories have played in judicial decisions, but also to see how this has helped us understand memory today. Finally, we consider the way in which the research on memory (true and false) has been successfully integrated into some courtroom procedures. PMID:25706242

The Effects of Feedback on Memory Strategies of Younger and Older Adults.

PubMed

Zhang, Fan; Zhang, Xin; Luo, Meng; Geng, Haiyan

2016-01-01

Existing literature suggests that feedback could effectively reduce false memories in younger adults. However, it is unclear whether memory performance in older adults also might be affected by feedback. The current study tested the hypothesis that older adults can use immediate feedback to adjust their memory strategy, similar to younger adults, but after feedback is removed, older adults may not be able to maintain using the memory strategy. Older adults will display more false memories than younger adults due to a reduction in attentional resources. In Study 1, both younger and older adults adjusted gist processing and item-specific processing biases based on the feedback given (i.e., biased and objective feedback). In Study 2 after the feedback was removed, only younger adults with full attention were able to maintain the feedback-shaped memory strategy; whereas, both younger adults with divided attention and older adults had increased false memories after feedback was removed. The findings suggest that environmental support helps older adults as well as younger adults to adopt a memory strategy that demands high attentional resources, but when the support is removed, older adults can no longer maintain such a strategy.

Selective verbal recognition memory impairments are associated with atrophy of the language network in non-semantic variants of primary progressive aphasia.

PubMed

Nilakantan, Aneesha S; Voss, Joel L; Weintraub, Sandra; Mesulam, M-Marsel; Rogalski, Emily J

2017-06-01

Primary progressive aphasia (PPA) is clinically defined by an initial loss of language function and preservation of other cognitive abilities, including episodic memory. While PPA primarily affects the left-lateralized perisylvian language network, some clinical neuropsychological tests suggest concurrent initial memory loss. The goal of this study was to test recognition memory of objects and words in the visual and auditory modality to separate language-processing impairments from retentive memory in PPA. Individuals with non-semantic PPA had longer reaction times and higher false alarms for auditory word stimuli compared to visual object stimuli. Moreover, false alarms for auditory word recognition memory were related to cortical thickness within the left inferior frontal gyrus and left temporal pole, while false alarms for visual object recognition memory was related to cortical thickness within the right-temporal pole. This pattern of results suggests that specific vulnerability in processing verbal stimuli can hinder episodic memory in PPA, and provides evidence for differential contributions of the left and right temporal poles in word and object recognition memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ad hoc categories and false memories: Memory illusions for categories created on-the-spot.

PubMed

Soro, Jerônimo C; Ferreira, Mário B; Semin, Gün R; Mata, André; Carneiro, Paula

2017-11-01

Three experiments were designed to test whether experimentally created ad hoc associative networks evoke false memories. We used the DRM (Deese, Roediger, McDermott) paradigm with lists of ad hoc categories composed of exemplars aggregated toward specific goals (e.g., going for a picnic) that do not share any consistent set of features. Experiment 1 revealed considerable levels of false recognitions of critical words from ad hoc categories. False recognitions occurred even when the lists were presented without an organizing theme (i.e., the category's label). Experiments 1 and 2 tested whether (a) the ease of identifying the categories' themes, and (b) the lists' backward associative strength could be driving the effect. List identifiability did not correlate with false recognition, and the effect remained even when backward associative strength was controlled for. Experiment 3 manipulated the distractor items in the recognition task to address the hypothesis that the salience of unrelated items could be facilitating the occurrence of the phenomenon. The effect remained when controlling for this source of facilitation. These results have implications for assumptions made by theories of false memories, namely the preexistence of associations in the activation-monitoring framework and the central role of gist extraction in fuzzy-trace theory, while providing evidence of the occurrence of false memories for more dynamic and context-dependent knowledge structures. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Exchange Protein Activated by cAMP Enhances Long-Term Memory Formation Independent of Protein Kinase A

ERIC Educational Resources Information Center

Ma, Nan; Abel, Ted; Hernandez, Pepe J.

2009-01-01

It is well established that cAMP signaling within neurons plays a major role in the formation of long-term memories--signaling thought to proceed through protein kinase A (PKA). However, here we show that exchange protein activated by cAMP (Epac) is able to enhance the formation of long-term memory in the hippocampus and appears to do so…

Spinoza's error: memory for truth and falsity.

PubMed

Nadarevic, Lena; Erdfelder, Edgar

2013-02-01

Two theoretical frameworks have been proposed to account for the representation of truth and falsity in human memory: the Cartesian model and the Spinozan model. Both models presume that during information processing a mental representation of the information is stored along with a tag indicating its truth value. However, the two models disagree on the nature of these tags. According to the Cartesian model, true information receives a "true" tag and false information receives a "false" tag. In contrast, the Spinozan model claims that only false information receives a "false" tag, whereas untagged information is automatically accepted as true. To test the Cartesian and Spinozan models, we conducted two source memory experiments in which participants studied true and false trivia statements from three different sources differing in credibility (i.e., presenting 100% true, 50% true and 50% false, or 100% false statements). In Experiment 1, half of the participants were informed about the source credibility prior to the study phase. As compared to a control group, this precue group showed improved source memory for both true and false statements, but not for statements with an uncertain validity status. Moreover, memory did not differ for truth and falsity in the precue group. As Experiment 2 revealed, this finding is replicated even when using a 1-week rather than a 20-min retention interval between study and test phases. The results of both experiments clearly contradict the Spinozan model but can be explained in terms of the Cartesian model.

The effect of warnings on false memories in young and older adults.

PubMed

McCabe, David P; Smith, Anderson D

2002-10-01

In the present experiments, we examined adult age differences in the ability to suppress false memories, using the Deese-Roediger-McDermott (DRM) paradigm (Deese, 1959; Roediger & McDermott, 1995). Participants studied lists of words (e.g., bed, rest, awake, etc.), each related to a nonpresented critical lure word (e.g., sleep). Typically, recognition tests reveal false alarms to critical lures at rates comparable to those for hits for studied words. In two experiments, separate groups of young and older adults were unwarned about the false memory effect, warned before studying the lists, or warned after study and before test. Lists were presented at either a slow rate (4 sec/word) or a faster rate (2 sec/word). Young adults were better able to discriminate between studied words and critical lures when warned about the DRM effect either before study or after study but before retrieval, and their performance improved with a slower presentation rate. Older adults were able to discriminate between studied words and critical lures when given warnings before study, but not when given warnings after study but before retrieval. Performance on a working memory capacity measure predicted false recognition following study and retrieval warnings. The results suggest that effective use of warnings to reduce false memories is contingent on the quality and type of encoded information, as well as on whether that information is accessed at retrieval. Furthermore, discriminating between similar sources of activation is dependent on working memory capacity, which declines with advancing age.

Why Do Pictures, but Not Visual Words, Reduce Older Adults’ False Memories?

PubMed Central

Smith, Rebekah E.; Hunt, R. Reed; Dunlap, Kathryn R.

2015-01-01

Prior work shows that false memories resulting from the study of associatively related lists are reduced for both young and older adults when the auditory presentation of study list words is accompanied by related pictures relative to when auditory word presentation is combined with visual presentation of the word. In contrast, young adults, but not older adults, show a reduction in false memories when presented with the visual word along with the auditory word relative to hearing the word only. In both the case of pictures relative to visual words and visual words relative to auditory words alone, the benefit of picture and visual words in reducing false memories has been explained in terms of monitoring for perceptual information. In our first experiment we provide the first simultaneous comparison of all three study presentation modalities (auditory only, auditory plus visual word, and auditory plus picture). Young and older adults show a reduction in false memories in the auditory plus picture condition, but only young adults show a reduction in the visual word condition relative to the auditory only condition. A second experiment investigates whether older adults fail to show a reduction in false memory in the visual word condition because they do not encode perceptual information in the visual word condition. In addition, the second experiment provides evidence that the failure of older adults to show the benefits of visual word presentation is related to reduced cognitive resources. PMID:26213799

Why do pictures, but not visual words, reduce older adults' false memories?

PubMed

Smith, Rebekah E; Hunt, R Reed; Dunlap, Kathryn R

2015-09-01

Prior work shows that false memories resulting from the study of associatively related lists are reduced for both young and older adults when the auditory presentation of study list words is accompanied by related pictures relative to when auditory word presentation is combined with visual presentation of the word. In contrast, young adults, but not older adults, show a reduction in false memories when presented with the visual word along with the auditory word relative to hearing the word only. In both cases of pictures relative to visual words and visual words relative to auditory words alone, the benefit of picture and visual words in reducing false memories has been explained in terms of monitoring for perceptual information. In our first experiment, we provide the first simultaneous comparison of all 3 study presentation modalities (auditory only, auditory plus visual word, and auditory plus picture). Young and older adults show a reduction in false memories in the auditory plus picture condition, but only young adults show a reduction in the visual word condition relative to the auditory only condition. A second experiment investigates whether older adults fail to show a reduction in false memory in the visual word condition because they do not encode perceptual information in the visual word condition. In addition, the second experiment provides evidence that the failure of older adults to show the benefits of visual word presentation is related to reduced cognitive resources. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Hippocampal 5-HT Input Regulates Memory Formation and Schaffer Collateral Excitation.

PubMed

Teixeira, Catia M; Rosen, Zev B; Suri, Deepika; Sun, Qian; Hersh, Marc; Sargin, Derya; Dincheva, Iva; Morgan, Ashlea A; Spivack, Stephen; Krok, Anne C; Hirschfeld-Stoler, Tessa; Lambe, Evelyn K; Siegelbaum, Steven A; Ansorge, Mark S

2018-06-06

The efficacy and duration of memory storage is regulated by neuromodulatory transmitter actions. While the modulatory transmitter serotonin (5-HT) plays an important role in implicit forms of memory in the invertebrate Aplysia, its function in explicit memory mediated by the mammalian hippocampus is less clear. Specifically, the consequences elicited by the spatio-temporal gradient of endogenous 5-HT release are not known. Here we applied optogenetic techniques in mice to gain insight into this fundamental biological process. We find that activation of serotonergic terminals in the hippocampal CA1 region both potentiates excitatory transmission at CA3-to-CA1 synapses and enhances spatial memory. Conversely, optogenetic silencing of CA1 5-HT terminals inhibits spatial memory. We furthermore find that synaptic potentiation is mediated by 5-HT4 receptors and that systemic modulation of 5-HT4 receptor function can bidirectionally impact memory formation. Collectively, these data reveal powerful modulatory influence of serotonergic synaptic input on hippocampal function and memory formation. Copyright © 2018 Elsevier Inc. All rights reserved.

Dopaminergic neurons write and update memories with cell-type-specific rules

PubMed Central

Aso, Yoshinori; Rubin, Gerald M

2016-01-01

Associative learning is thought to involve parallel and distributed mechanisms of memory formation and storage. In Drosophila, the mushroom body (MB) is the major site of associative odor memory formation. Previously we described the anatomy of the adult MB and defined 20 types of dopaminergic neurons (DANs) that each innervate distinct MB compartments (Aso et al., 2014a, 2014b). Here we compare the properties of memories formed by optogenetic activation of individual DAN cell types. We found extensive differences in training requirements for memory formation, decay dynamics, storage capacity and flexibility to learn new associations. Even a single DAN cell type can either write or reduce an aversive memory, or write an appetitive memory, depending on when it is activated relative to odor delivery. Our results show that different learning rules are executed in seemingly parallel memory systems, providing multiple distinct circuit-based strategies to predict future events from past experiences. DOI: http://dx.doi.org/10.7554/eLife.16135.001 PMID:27441388

Protein Phosphatase-1 Inhibitor-2 Is a Novel Memory Suppressor.

PubMed

Yang, Hongtian; Hou, Hailong; Pahng, Amanda; Gu, Hua; Nairn, Angus C; Tang, Ya-Ping; Colombo, Paul J; Xia, Houhui

2015-11-11

Reversible phosphorylation, a fundamental regulatory mechanism required for many biological processes including memory formation, is coordinated by the opposing actions of protein kinases and phosphatases. Type I protein phosphatase (PP1), in particular, has been shown to constrain learning and memory formation. However, how PP1 might be regulated in memory is still not clear. Our previous work has elucidated that PP1 inhibitor-2 (I-2) is an endogenous regulator of PP1 in hippocampal and cortical neurons (Hou et al., 2013). Contrary to expectation, our studies of contextual fear conditioning and novel object recognition in I-2 heterozygous mice suggest that I-2 is a memory suppressor. In addition, lentiviral knock-down of I-2 in the rat dorsal hippocampus facilitated memory for tasks dependent on the hippocampus. Our data indicate that I-2 suppresses memory formation, probably via negatively regulating the phosphorylation of cAMP/calcium response element-binding protein (CREB) at serine 133 and CREB-mediated gene expression in dorsal hippocampus. Surprisingly, the data from both biochemical and behavioral studies suggest that I-2, despite its assumed action as a PP1 inhibitor, is a positive regulator of PP1 function in memory formation. We found that inhibitor-2 acts as a memory suppressor through its positive functional influence on type I protein phosphatase (PP1), likely resulting in negative regulation of cAMP/calcium response element-binding protein (CREB) and CREB-activated gene expression. Our studies thus provide an interesting example of a molecule with an in vivo function that is opposite to its in vitro function. PP1 plays critical roles in many essential physiological functions such as cell mitosis and glucose metabolism in addition to its known role in memory formation. PP1 pharmacological inhibitors would thus not be able to serve as good therapeutic reagents because of its many targets. However, identification of PP1 inhibitor-2 as a critical contributor to suppression of memory formation by PP1 may provide a novel therapeutic target for memory-related diseases. Copyright © 2015 the authors 0270-6474/15/3515082-06$15.00/0.

Maltreated and non-maltreated children's true and false memories of neutral and emotional word lists in the Deese/Roediger-McDermott task.

PubMed

Baugerud, Gunn Astrid; Howe, Mark L; Magnussen, Svein; Melinder, Annika

2016-03-01

Maltreated (n=26) and non-maltreated (n=31) 7- to 12-year-old children were tested on the Deese/Roediger-McDermott (DRM) false memory task using emotional and neutral word lists. True recall was significantly better for non-maltreated than maltreated children regardless of list valence. The proportion of false recall for neutral lists was comparable regardless of maltreatment status. However, maltreated children showed a significantly higher false recall rate for the emotional lists than non-maltreated children. Together, these results provide new evidence that maltreated children could be more prone to false memory illusions for negatively valenced information than their non-maltreated counterparts. Copyright © 2015 Elsevier Inc. All rights reserved.

The use of metacognitive strategies to decrease false memories in source monitoring in patients with mild cognitive impairment.

PubMed

Deason, Rebecca G; Nadkarni, Neil A; Tat, Michelle J; Flannery, Sean; Frustace, Bruno; Ally, Brandon A; Budson, Andrew E

2017-06-01

Patients with amnestic mild cognitive impairment (MCI) and Alzheimer's disease (AD) often demonstrate high rates of false memories, leading to stressful and frustrating situations for both patients and caregivers in everyday life. Sometimes these false memories are due to failures in monitoring the source of the information. In the current study, we examined interventions aimed to enhance the use of the metacognitive "recall-to-reject" memory strategy. Such interventions could improve source memory and decrease false memory in patients with MCI. Because the picture superiority effect (better memory for pictures compared to words) has been shown to be present in both patients with MCI and healthy older controls, we investigated whether pictures could help patients with MCI use a recall-to-reject strategy in a simulation of real-world source memory task. In this experiment, patients with MCI and healthy older adults were asked to simulate preparing for and then taking a trip to the market. Subjects first studied 30 pictures of items in their "cupboard," followed by a list of 30 words of items on their "shopping list." At test, participants saw 90 pictures (30 cupboard, 30 list, 30 new) organized as they would be if walking down the market aisles, and are provided with either standard or metacognitive instructions. With standard instructions, they were asked if they needed to buy the item. With the metacognitive instructions, they were asked a series of questions to help guide them through a recall-to-reject strategy to highlight the different sources of memories. Results showed that the metacognitive instructions did significantly reduce the false memory rates for patients with MCI. Further studies need to investigate how to best implement these practical strategies into the everyday lives of patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

How Does Distinctive Processing Reduce False Recall?

ERIC Educational Resources Information Center

Hunt, R. Reed; Smith, Rebekah E.; Dunlap, Kathryn R.

2011-01-01

False memories arising from associatively related lists are a robust phenomenon that resists many efforts to prevent it. However, a few variables have been shown to reduce this form of false memory. Explanations for how the reduction is accomplished have focused on either output monitoring processes or constraints on access, but neither idea alone…

Roles of calcium/calmodulin-dependent kinase II in long-term memory formation in crickets.

PubMed

Mizunami, Makoto; Nemoto, Yuko; Terao, Kanta; Hamanaka, Yoshitaka; Matsumoto, Yukihisa

2014-01-01

Ca(2+)/calmodulin (CaM)-dependent protein kinase II (CaMKII) is a key molecule in many systems of learning and memory in vertebrates, but roles of CaMKII in invertebrates have not been characterized in detail. We have suggested that serial activation of NO/cGMP signaling, cyclic nucleotide-gated channel, Ca(2+)/CaM and cAMP signaling participates in long-term memory (LTM) formation in olfactory conditioning in crickets, and here we show participation of CaMKII in LTM formation and propose its site of action in the biochemical cascades. Crickets subjected to 3-trial conditioning to associate an odor with reward exhibited memory that lasts for a few days, which is characterized as protein synthesis-dependent LTM. In contrast, animals subjected to 1-trial conditioning exhibited memory that lasts for only several hours (mid-term memory, MTM). Injection of a CaMKII inhibitor prior to 3-trial conditioning impaired 1-day memory retention but not 1-hour memory retention, suggesting that CaMKII participates in LTM formation but not in MTM formation. Animals injected with a cGMP analogue, calcium ionophore or cAMP analogue prior to 1-trial conditioning exhibited 1-day retention, and co-injection of a CaMKII inhibitor impaired induction of LTM by the cGMP analogue or that by the calcium ionophore but not that by the cAMP analogue, suggesting that CaMKII is downstream of cGMP production and Ca(2+) influx and upstream of cAMP production in biochemical cascades for LTM formation. Animals injected with an adenylyl cyclase (AC) activator prior to 1-trial conditioning exhibited 1-day retention. Interestingly, a CaMKII inhibitor impaired LTM induction by the AC activator, although AC is expected to be a downstream target of CaMKII. The results suggest that CaMKII interacts with AC to facilitate cAMP production for LTM formation. We propose that CaMKII serves as a key molecule for interplay between Ca(2+) signaling and cAMP signaling for LTM formation, a new role of CaMKII in learning and memory.

The role of rehearsal and generation in false memory creation.

PubMed

Marsh, Elizabeth J; Bower, Gordon H

2004-11-01

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 illusion of the positive: the impact of natural and induced mood on older adults' false recall.

PubMed

Emery, Lisa; Hess, Thomas M; Elliot, Tonya

2012-11-01

Recent research suggests that affective and motivational processes can influence age differences in memory. In the current study, we examine the impact of both natural and induced mood state on age differences in false recall. Older and younger adults performed a version of the Deese-Roediger-McDermott (DRM; Roediger & McDermott, 1995 , Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 803) false memory paradigm in either their natural mood state or after a positive or negative mood induction. Results indicated that, after accounting for age differences in basic cognitive function, age-related differences in positive mood during the testing session were related to increased false recall in older adults. Inducing older adults into a positive mood also exacerbated age differences in false memory. In contrast, veridical recall did not appear to be systematically influenced by mood. Together, these results suggest that positive mood states can impact older adults' information processing and potentially increase underlying cognitive age differences.

Acute effects of triazolam on false recognition.

PubMed

Mintzer, M Z; Griffiths, R R

2000-12-01

Neuropsychological, neuroimaging, and electrophysiological techniques have been applied to the study of false recognition; however, psychopharmacological techniques have not been applied. Benzodiazepine sedative/anxiolytic drugs produce memory deficits similar to those observed in organic amnesia and may be useful tools for studying normal and abnormal memory mechanisms. The present double-blind, placebo-controlled repeated measures study examined the acute effects of orally administered triazolam (Halcion; 0.125 and 0.25 mg/70 kg), a benzodiazepine hypnotic, on performance in the Deese (1959)/Roediger-McDermott (1995) false recognition paradigm in 24 healthy volunteers. Paralleling previous demonstrations in amnesic patients, triazolam produced significant dose-related reductions in false recognition rates to nonstudied words associatively related to studied words, suggesting that false recognition relies on normal memory mechanisms impaired in benzodiazepine-induced amnesia. The results also suggested that relative to placebo, triazolam reduced participants' reliance on memory for item-specific versus list-common semantic information and reduced participants' use of remember versus know responses.

Imaging the Reconstruction of True and False Memories Using Sensory Reactivation and the Misinformation Paradigms

ERIC Educational Resources Information Center

Stark, Craig E. L.; Okado, Yoko; Loftus, Elizabeth F.

2010-01-01

Many current theories of false memories propose that, when we retrieve a memory, we are not reactivating a veridical, fixed representation of a past event, but are rather reactivating incomplete fragments that may be accurate or distorted and may have arisen from other events. By presenting the two phases of the misinformation paradigm in…

The Role of Memory Activation in Creating False Memories of Encoding Context

ERIC Educational Resources Information Center

Arndt, Jason

2010-01-01

Using 3 experiments, I examined false memory for encoding context by presenting Deese-Roediger-McDermott themes (Deese, 1959; Roediger & McDermott, 1995) in usual-looking fonts and by testing related, but unstudied, lure items in a font that was shown during encoding. In 2 of the experiments, testing lure items in the font used to study their…

Ad Hoc Categories and False Memories: Memory Illusions for Categories Created On-The-Spot

ERIC Educational Resources Information Center

Soro, Jerônimo C.; Ferreira, Mário B.; Semin, Gün R.; Mata, André; Carneiro, Paula

2017-01-01

Three experiments were designed to test whether experimentally created ad hoc associative networks evoke false memories. We used the DRM (Deese, Roediger, McDermott) paradigm with lists of ad hoc categories composed of exemplars aggregated toward specific goals (e.g., going for a picnic) that do not share any consistent set of features. Experiment…

Sleep and eyewitness memory: Fewer false identifications after sleep when the target is absent from the lineup.

PubMed

Stepan, Michelle E; Dehnke, Taylor M; Fenn, Kimberly M

2017-01-01

Inaccurate eyewitness identifications are the leading cause of known false convictions in the United States. Moreover, improving eyewitness memory is difficult and often unsuccessful. Sleep consistently strengthens and protects memory from interference, particularly when a recall test is used. However, the effect of sleep on recognition memory is more equivocal. Eyewitness identification tests are often recognition based, thus leaving open the question of how sleep affects recognition performance in an eyewitness context. In the current study, we investigated the effect of sleep on eyewitness memory. Participants watched a video of a mock-crime and attempted to identify the perpetrator from a simultaneous lineup after a 12-hour retention interval that either spanned a waking day or night of sleep. In Experiment 1, we used a target-present lineup and, in Experiment 2, we used a target-absent lineup in order to investigate correct and false identifications, respectively. Sleep reduced false identifications in the target-absent lineup (Experiment 2) but had no effect on correct identifications in the target-present lineup (Experiment 1). These results are discussed with respect to memory strength and decision making strategies.

Sleep and eyewitness memory: Fewer false identifications after sleep when the target is absent from the lineup

PubMed Central

Dehnke, Taylor M.; Fenn, Kimberly M.

2017-01-01

Inaccurate eyewitness identifications are the leading cause of known false convictions in the United States. Moreover, improving eyewitness memory is difficult and often unsuccessful. Sleep consistently strengthens and protects memory from interference, particularly when a recall test is used. However, the effect of sleep on recognition memory is more equivocal. Eyewitness identification tests are often recognition based, thus leaving open the question of how sleep affects recognition performance in an eyewitness context. In the current study, we investigated the effect of sleep on eyewitness memory. Participants watched a video of a mock-crime and attempted to identify the perpetrator from a simultaneous lineup after a 12-hour retention interval that either spanned a waking day or night of sleep. In Experiment 1, we used a target-present lineup and, in Experiment 2, we used a target-absent lineup in order to investigate correct and false identifications, respectively. Sleep reduced false identifications in the target-absent lineup (Experiment 2) but had no effect on correct identifications in the target-present lineup (Experiment 1). These results are discussed with respect to memory strength and decision making strategies. PMID:28877169

Temporal binding function of dorsal CA1 is critical for declarative memory formation

PubMed Central

Sellami, Azza; Al Abed, Alice Shaam; Brayda-Bruno, Laurent; Etchamendy, Nicole; Valério, Stéphane; Oulé, Marie; Pantaléon, Laura; Lamothe, Valérie; Potier, Mylène; Bernard, Katy; Jabourian, Maritza; Herry, Cyril; Mons, Nicole; Piazza, Pier-Vincenzo; Eichenbaum, Howard; Marighetto, Aline

2017-01-01

Temporal binding, the process that enables association between discontiguous stimuli in memory, and relational organization, a process that enables the flexibility of declarative memories, are both hippocampus-dependent and decline in aging. However, how these two processes are related in supporting declarative memory formation and how they are compromised in age-related memory loss remain hypothetical. We here identify a causal link between these two features of declarative memory: Temporal binding is a necessary condition for the relational organization of discontiguous events. We demonstrate that the formation of a relational memory is limited by the capability of temporal binding, which depends on dorsal (d)CA1 activity over time intervals and diminishes in aging. Conversely, relational representation is successful even in aged individuals when the demand on temporal binding is minimized, showing that relational/declarative memory per se is not impaired in aging. Thus, bridging temporal intervals by dCA1 activity is a critical foundation of relational representation, and a deterioration of this mechanism is responsible for the age-associated memory impairment. PMID:28874586

Temporal binding function of dorsal CA1 is critical for declarative memory formation.

PubMed

Sellami, Azza; Al Abed, Alice Shaam; Brayda-Bruno, Laurent; Etchamendy, Nicole; Valério, Stéphane; Oulé, Marie; Pantaléon, Laura; Lamothe, Valérie; Potier, Mylène; Bernard, Katy; Jabourian, Maritza; Herry, Cyril; Mons, Nicole; Piazza, Pier-Vincenzo; Eichenbaum, Howard; Marighetto, Aline

2017-09-19

Temporal binding, the process that enables association between discontiguous stimuli in memory, and relational organization, a process that enables the flexibility of declarative memories, are both hippocampus-dependent and decline in aging. However, how these two processes are related in supporting declarative memory formation and how they are compromised in age-related memory loss remain hypothetical. We here identify a causal link between these two features of declarative memory: Temporal binding is a necessary condition for the relational organization of discontiguous events. We demonstrate that the formation of a relational memory is limited by the capability of temporal binding, which depends on dorsal (d)CA1 activity over time intervals and diminishes in aging. Conversely, relational representation is successful even in aged individuals when the demand on temporal binding is minimized, showing that relational/declarative memory per se is not impaired in aging. Thus, bridging temporal intervals by dCA1 activity is a critical foundation of relational representation, and a deterioration of this mechanism is responsible for the age-associated memory impairment.

Continuing the search for the engram: examining the mechanism of fear memories.

PubMed

Josselyn, Sheena A

2010-07-01

The goal of my research is to gain insight using rodent models into the fundamental molecular, cellular and systems that make up the base of memory formation. My work focuses on fear memories. Aberrant fear and/or anxiety may be at the heart of many psychiatric disorders. In this article, I review the results of my research group; these results show that particular neurons in the lateral amygdala, a brain region important for fear, are specifically involved in particular fear memories. We started by showing that the transcription factor CREB (cAMP/Ca(2+) response element binding protein) plays a key role in the formation of fear memories. Next, we used viral vectors to overexpress CREB in a subset of lateral amygdala neurons. This not only facilitated fear memory formation but also "drove" the memory into the neurons with relatively increased CREB function. Finally, we showed that selective ablation of the neurons overexpressing CREB in the lateral amygdala selectively erased the fear memory. These findings are the first to show disruption of a specific memory by disrupting select neurons within a distributed network.

VGF and Its C-Terminal Peptide TLQP-62 Regulate Memory Formation in Hippocampus via a BDNF-TrkB-Dependent Mechanism.

PubMed

Lin, Wei-Jye; Jiang, Cheng; Sadahiro, Masato; Bozdagi, Ozlem; Vulchanova, Lucy; Alberini, Cristina M; Salton, Stephen R

2015-07-15

Regulated expression and secretion of BDNF, which activates TrkB receptor signaling, is known to play a critical role in cognition. Identification of additional modulators of cognitive behavior that regulate activity-dependent BDNF secretion and/or potentiate TrkB receptor signaling would therefore be of considerable interest. In this study, we show in the adult mouse hippocampus that expression of the granin family gene Vgf and secretion of its C-terminal VGF-derived peptide TLQP-62 are required for fear memory formation. We found that hippocampal VGF expression and TLQP-62 levels were transiently induced after fear memory training and that sequestering secreted TLQP-62 peptide in the hippocampus immediately after training impaired memory formation. Reduced VGF expression was found to impair learning-evoked Rac1 induction and phosphorylation of the synaptic plasticity markers cofilin and synapsin in the adult mouse hippocampus. Moreover, TLQP-62 induced acute, transient activation of the TrkB receptor and subsequent CREB phosphorylation in hippocampal slice preparations and its administration immediately after training enhanced long-term memory formation. A critical role of BDNF-TrkB signaling as a downstream effector in VGF/TLQP-62-mediated memory consolidation was further revealed by posttraining activation of BDNF-TrkB signaling, which rescued impaired fear memory resulting from hippocampal administration of anti-VGF antibodies or germline VGF ablation in mice. We propose that VGF is a critical component of a positive BDNF-TrkB regulatory loop and, upon its induced expression by memory training, the TLQP-62 peptide rapidly reinforces BDNF-TrkB signaling, regulating hippocampal memory consolidation. Identification of the cellular and molecular mechanisms that regulate long-term memory formation and storage may provide alternative treatment modalities for degenerative and neuropsychiatric memory disorders. The neurotrophin BDNF plays a prominent role in cognitive function, and rapidly and robustly induces expression of VGF, a secreted neuronal peptide precursor. VGF knock-out mice have impaired fear and spatial memory. Our study shows that VGF and VGF-derived peptide TLQP-62 are transiently induced after fear memory training, leading to increased BDNF/TrkB signaling, and that sequestration of hippocampal TLQP-62 immediately after training impairs memory formation. We propose that TLQP-62 is a critical component of a positive regulatory loop that is induced by memory training, rapidly reinforces BDNF-TrkB signaling, and is required for hippocampal memory consolidation. Copyright © 2015 the authors 0270-6474/15/3510344-14$15.00/0.

VGF and Its C-Terminal Peptide TLQP-62 Regulate Memory Formation in Hippocampus via a BDNF-TrkB-Dependent Mechanism

PubMed Central

Lin, Wei-Jye; Jiang, Cheng; Sadahiro, Masato; Bozdagi, Ozlem; Vulchanova, Lucy; Alberini, Cristina M.

2015-01-01

Regulated expression and secretion of BDNF, which activates TrkB receptor signaling, is known to play a critical role in cognition. Identification of additional modulators of cognitive behavior that regulate activity-dependent BDNF secretion and/or potentiate TrkB receptor signaling would therefore be of considerable interest. In this study, we show in the adult mouse hippocampus that expression of the granin family gene Vgf and secretion of its C-terminal VGF-derived peptide TLQP-62 are required for fear memory formation. We found that hippocampal VGF expression and TLQP-62 levels were transiently induced after fear memory training and that sequestering secreted TLQP-62 peptide in the hippocampus immediately after training impaired memory formation. Reduced VGF expression was found to impair learning-evoked Rac1 induction and phosphorylation of the synaptic plasticity markers cofilin and synapsin in the adult mouse hippocampus. Moreover, TLQP-62 induced acute, transient activation of the TrkB receptor and subsequent CREB phosphorylation in hippocampal slice preparations and its administration immediately after training enhanced long-term memory formation. A critical role of BDNF-TrkB signaling as a downstream effector in VGF/TLQP-62-mediated memory consolidation was further revealed by posttraining activation of BDNF-TrkB signaling, which rescued impaired fear memory resulting from hippocampal administration of anti-VGF antibodies or germline VGF ablation in mice. We propose that VGF is a critical component of a positive BDNF-TrkB regulatory loop and, upon its induced expression by memory training, the TLQP-62 peptide rapidly reinforces BDNF-TrkB signaling, regulating hippocampal memory consolidation. SIGNIFICANCE STATEMENT Identification of the cellular and molecular mechanisms that regulate long-term memory formation and storage may provide alternative treatment modalities for degenerative and neuropsychiatric memory disorders. The neurotrophin BDNF plays a prominent role in cognitive function, and rapidly and robustly induces expression of VGF, a secreted neuronal peptide precursor. VGF knock-out mice have impaired fear and spatial memory. Our study shows that VGF and VGF-derived peptide TLQP-62 are transiently induced after fear memory training, leading to increased BDNF/TrkB signaling, and that sequestration of hippocampal TLQP-62 immediately after training impairs memory formation. We propose that TLQP-62 is a critical component of a positive regulatory loop that is induced by memory training, rapidly reinforces BDNF-TrkB signaling, and is required for hippocampal memory consolidation. PMID:26180209

Is there a positive bias in false recognition? Evidence from confabulating amnesia patients.

PubMed

Alkathiri, Nura H; Morris, Robin G; Kopelman, Michael D

2015-10-01

Although there is some evidence for a positive emotional bias in the content of confabulations in brain damaged patients, findings have been inconsistent. The present study used the semantic-associates procedure to induce false recall and false recognition in order to examine whether a positive bias would be found in confabulating amnesic patients, relative to non-confabulating amnesic patients and healthy controls. Lists of positive, negative and neutral words were presented in order to induce false recall or false recognition of non-presented (but semantically associated) words. The latter were termed 'critical intrusions'. Thirteen confabulating amnesic patients, 13 non-confabulating amnesic patients and 13 healthy controls were investigated. Confabulating patients falsely recognised a higher proportion of positive (but unrelated) words, compared with non-confabulating patients and healthy controls. No differences were found for recall memory. Signal detection analysis, however, indicated that the positive bias for false recognition memory might reflect weaker memory in the confabulating amnesic group. This suggested that amnesia patients with weaker memory are more likely to confabulate and the content of these confabulations are more likely to be positive. Copyright © 2015 Elsevier Ltd. All rights reserved.

Neural and Cellular Mechanisms of Fear and Extinction Memory Formation

PubMed Central

Orsini, Caitlin A.; Maren, Stephen

2012-01-01

Over the course of natural history, countless animal species have evolved adaptive behavioral systems to cope with dangerous situations and promote survival. Emotional memories are central to these defense systems because they are rapidly acquired and prepare organisms for future threat. Unfortunately, the persistence and intrusion of memories of fearful experiences are quite common and can lead to pathogenic conditions, such as anxiety and phobias. Over the course of the last thirty years, neuroscientists and psychologists alike have attempted to understand the mechanisms by which the brain encodes and maintains these aversive memories. Of equal interest, though, is the neurobiology of extinction memory formation as this may shape current therapeutic techniques. Here we review the extant literature on the neurobiology of fear and extinction memory formation, with a strong focus on the cellular and molecular mechanisms underlying these processes. PMID:22230704

Fuzzy-trace theory: dual processes in memory, reasoning, and cognitive neuroscience.

PubMed

Brainerd, C J; Reyna, V F

2001-01-01

Fuzzy-trace theory has evolved in response to counterintuitive data on how memory development influences the development of reasoning. The two traditional perspectives on memory-reasoning relations--the necessity and constructivist hypotheses--stipulate that the accuracy of children's memory for problem information and the accuracy of their reasoning are closely intertwined, albeit for different reasons. However, contrary to necessity, correlational and experimental dissociations have been found between children's memory for problem information that is determinative in solving certain problems and their solutions of those problems. In these same tasks, age changes in memory for problem information appear to be dissociated from age changes in reasoning. Contrary to constructivism, correlational and experimental dissociations also have been found between children's performance on memory tests for actual experience and memory tests for the meaning of experience. As in memory-reasoning studies, age changes in one type of memory performance do not seem to be closely connected to age changes in the other type of performance. Subsequent experiments have led to dual-process accounts in both the memory and reasoning spheres. The account of memory development features four other principles: parallel verbatim-gist storage, dissociated verbatim-gist retrieval, memorial bases of conscious recollection, and identity/similarity processes. The account of the development of reasoning features three principles: gist extraction, fuzzy-to-verbatim continua, and fuzzy-processing preferences. The fuzzy-processing preference is a particularly important notion because it implies that gist-based intuitive reasoning often suffices to deliver "logical" solutions and that such reasoning confers multiple cognitive advantages that enhance accuracy. The explanation of memory-reasoning dissociations in cognitive development then falls out of fuzzy-trace theory's dual-process models of memory and reasoning. More explicitly, in childhood reasoning tasks, it is assumed that both verbatim and gist traces of problem information are stored. Responding accurately to memory tests for presented problem information depends primarily on verbatim memory abilities (preserving traces of that information and accessing them when the appropriate memory probes are administered). However, accurate solutions to reasoning problems depend primarily on gist-memory abilities (extracting the correct gist from problem information, focusing on that gist during reasoning, and accessing reasoning operations that process that gist). Because verbatim and gist memories exhibit considerable dissociation, both during storage and when they are subsequently accessed on memory tests, dissociations of verbatim-based memory performance from gist-based reasoning are predictable. Conversely, associations are predicted in situations in which memory and reasoning are based on the same verbatim traces (Brainerd & Reyna, 1988) and in situations in which memory and reasoning are based on the same gist traces (Reyna & Kiernan, 1994). Fuzzy-trace theory's memory and reasoning principles have been applied in other research domains. Four such domains are developmental cognitive neuroscience studies of false memory, studies of false memory in brain-damaged patients, studies of reasoning errors in judgment and decision making, and studies of retrieval mechanisms in recall. In the first domain, the principles of parallel verbatim-gist storage, dissociated verbatim-gist retrieval, and identity/similarity processes have been used to explain both spontaneous and implanted false reports in children and in the elderly. These explanations have produced some surprising predictions that have been verified: false reports do not merely decline with age during childhood but increase under theoretically specified conditions; reports of events that were not experienced can nevertheless be highly persistent over time; and false reports can be suppressed by retrieving verbatim traces of corresponding true events. In the second domain, the same principles have been invoked to explain why some forms of brain damage lead to elevated levels of false memory and other forms lead to reduced levels of false memory. In the third domain, the principles of gist extraction, fuzzy-to-verbatim continua, and fuzzy-processing preferences have been exploited to formulate a general theory of loci of processing failures in judgment and decision making, cluminating in a developmental account of degrees of rationality that distinguishes more and less advanced reasoning. This theory has in turn been used to formulate local models, such as the inclusion illusions model, that explain the characteristic reasoning errors that are observed on specific judgment and decision-making tasks. Finally, in the fourth domain, a dual-process conception of recall has been derived from the principles of parallel verbatim-gist storage and dissociated verbatim-gist retrieval. In this conception, which has been used to explain cognitive triage effects in recall and robust false recall, targets are recalled either by directly accessing their verbatim traces and reading the retrieved information out of consciousness or by reconstructively processing their gist traces.

The malleability of developmental trends in neutral and negative memory illusions.

PubMed

Otgaar, Henry; Howe, Mark L; Brackmann, Nathalie; Smeets, Tom

2016-01-01

Among many legal professionals and memory researchers there exists the assumption that susceptibility to false memory decreases with age. In 4 misinformation experiments, we show that under conditions that focus on the meaning of experiences, children are not always the most susceptible to suggestion-induced false memories. We begin by presenting a short overview of previous developmental false memory studies, the majority of which have found that the susceptibility to misinformation decreases with age. In Experiment 1, 6/7-year-olds, 11/12-year-olds, and adults received a video and were confronted with misinformation about related but nonpresented details. Older children and adults had higher misinformation acceptance rates than younger children. In Experiment 2, we replicated this finding adding a younger child group (4/6-year-olds). In Experiments 3 and 4, we used new material and again found that susceptibility to misinformation increased with age. Together, these experiments show that children's memory accuracy is not necessarily inferior to that of adults.' (c) 2015 APA, all rights reserved).

Syntactic Recursion Facilitates and Working Memory Predicts Recursive Theory of Mind

PubMed Central

Arslan, Burcu; Hohenberger, Annette; Verbrugge, Rineke

2017-01-01

In this study, we focus on the possible roles of second-order syntactic recursion and working memory in terms of simple and complex span tasks in the development of second-order false belief reasoning. We tested 89 Turkish children in two age groups, one younger (4;6–6;5 years) and one older (6;7–8;10 years). Although second-order syntactic recursion is significantly correlated with the second-order false belief task, results of ordinal logistic regressions revealed that the main predictor of second-order false belief reasoning is complex working memory span. Unlike simple working memory and second-order syntactic recursion tasks, the complex working memory task required processing information serially with additional reasoning demands that require complex working memory strategies. Based on our results, we propose that children’s second-order theory of mind develops when they have efficient reasoning rules to process embedded beliefs serially, thus overcoming a possible serial processing bottleneck. PMID:28072823

The Malleability of Developmental Trends in Neutral and Negative Memory Illusions

PubMed Central

2016-01-01

Among many legal professionals and memory researchers there exists the assumption that susceptibility to false memory decreases with age. In 4 misinformation experiments, we show that under conditions that focus on the meaning of experiences, children are not always the most susceptible to suggestion-induced false memories. We begin by presenting a short overview of previous developmental false memory studies, the majority of which have found that the susceptibility to misinformation decreases with age. In Experiment 1, 6/7-year-olds, 11/12-year-olds, and adults received a video and were confronted with misinformation about related but nonpresented details. Older children and adults had higher misinformation acceptance rates than younger children. In Experiment 2, we replicated this finding adding a younger child group (4/6-year-olds). In Experiments 3 and 4, we used new material and again found that susceptibility to misinformation increased with age. Together, these experiments show that children’s memory accuracy is not necessarily inferior to that of adults.’ PMID:26709588

Does stress remove the HDAC brakes for the formation and persistence of long-term memory?

PubMed

White, André O; Wood, Marcelo A

2014-07-01

It has been known for numerous decades that gene expression is required for long-lasting forms of memory. In the past decade, the study of epigenetic mechanisms in memory processes has revealed yet another layer of complexity in the regulation of gene expression. Epigenetic mechanisms do not only provide complexity in the protein regulatory complexes that control coordinate transcription for specific cell function, but the epigenome encodes critical information that integrates experience and cellular history for specific cell functions as well. Thus, epigenetic mechanisms provide a unique mechanism of gene expression regulation for memory processes. This may be why critical negative regulators of gene expression, such as histone deacetylases (HDACs), have powerful effects on the formation and persistence of memory. For example, HDAC inhibition has been shown to transform a subthreshold learning event into robust long-term memory and also generate a form of long-term memory that persists beyond the point at which normal long-term memory fails. A key question that is explored in this review, from a learning and memory perspective, is whether stress-dependent signaling drives the formation and persistence of long-term memory via HDAC-dependent mechanisms. Copyright © 2013 Elsevier Inc. All rights reserved.

Does stress remove the HDAC brakes for the formation and persistence of long-term memory?

PubMed Central

White, André O.; Wood, Marcelo A.

2013-01-01

It has been known for numerous decades that gene expression is required for long-lasting forms of memory. In the past decade, the study of epigenetic mechanisms in memory processes has revealed yet another layer of complexity in the regulation of gene expression. Epigenetic mechanisms do not only provide complexity in the protein regulatory complexes that control coordinate transcription for specific cell function, but the epigenome encodes critical information that integrates experience and cellular history for specific cell functions as well. Thus, epigenetic mechanisms provide a unique mechanism of gene expression regulation for memory processes. This may be why critical negative regulators of gene expression, such as histone deacetylases (HDACs), have powerful effects on the formation and persistence of memory. For example, HDAC inhibition has been shown to transform a subthreshold learning event into robust long-term memory and also generate a form of long-term memory that persists beyond the point at which normal long-term memory fails. A key question that is explored in this review, from a learning and memory perspective, is whether stress-dependent signaling drives the formation and persistence of long-term memory via HDAC-dependent mechanisms. PMID:24149059

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

PubMed

Parker, Andrew; Dagnall, Neil

2018-04-01

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.

Overexpression of SIRT6 in the hippocampal CA1 impairs the formation of long-term contextual fear memory

PubMed Central

Yin, Xi; Gao, Yuan; Shi, Hai-Shui; Song, Li; Wang, Jie-Chao; Shao, Juan; Geng, Xu-Hong; Xue, Gai; Li, Jian-Li; Hou, Yan-Ning

2016-01-01

Histone modifications have been implicated in learning and memory. Our previous transcriptome data showed that expression of sirtuins 6 (SIRT6), a member of Histone deacetylases (HDACs) family in the hippocampal cornu ammonis 1 (CA1) was decreased after contextual fear conditioning. However, the role of SIRT6 in the formation of memory is still elusive. In the present study, we found that contextual fear conditioning inhibited translational expression of SIRT6 in the CA1. Microinfusion of lentiviral vector-expressing SIRT6 into theCA1 region selectively enhanced the expression of SIRT6 and impaired the formation of long-term contextual fear memory without affecting short-term fear memory. The overexpression of SIRT6 in the CA1 had no effect on anxiety-like behaviors or locomotor activity. Also, we also found that SIRT6 overexpression significantly inhibited the expression of insulin-like factor 2 (IGF2) and amounts of proteins and/or phosphoproteins (e.g. Akt, pAkt, mTOR and p-mTOR) related to the IGF2 signal pathway in the CA1. These results demonstrate that the overexpression of SIRT6 in the CA1 impaired the formation of long-term fear memory, and SIRT6 in the CA1 may negatively modulate the formation of contextual fear memory via inhibiting the IGF signaling pathway. PMID:26732053

Recall of Details Never Experienced: Effects of Age, Repetition, and Semantic Cues

ERIC Educational Resources Information Center

Holliday, Robyn E.; Reyna, Valerie F.; Brainerd, Charles J.

2008-01-01

To test theoretical predictions about the role of meaning connections in false memory, the effects of semantic cues and list repetition on children's false memories were evaluated across early childhood to mid-adolescence using the Deese-Roediger-McDermott (DRM) paradigm. True recall and false recall increased from 7 to 13 years. Study list…

Why Distinctive Information Reduces False Memories: Evidence for Both Impoverished Relational-Encoding and Distinctiveness Heuristic Accounts

ERIC Educational Resources Information Center

Hege, Amanda C. G.; Dodson, Chad S.

2004-01-01

Two accounts explain why studying pictures reduces false memories within the Deese-Roediger-McDermott paradigm (J. Deese, 1959; H. L. Roediger & K. B. McDermott, 1995). The impoverished relational-encoding account suggests that studying pictures interferes with the encoding of relational information, which is the primary basis for false memories…

Do Children "DRM" Like Adults? False Memory Production in Children

ERIC Educational Resources Information Center

Metzger, Richard L.; Warren, Amye R.; Shelton, Jill T.; Price, Jodi; Reed, Andrea W.; Williams, Danny

2008-01-01

The Deese/Roediger-McDermott (DRM) paradigm was used to investigate developmental trends in accurate and false memory production. In Experiment 1, DRM lists adjusted to be more consistent with children's vocabulary were used with 2nd graders, 8th graders, and college students. Accurate and false recall and recognition increased with age, but…

A role for autophagy in long-term spatial memory formation in male rodents.

PubMed

Hylin, Michael J; Zhao, Jing; Tangavelou, Karthikeyan; Rozas, Natalia S; Hood, Kimberly N; MacGowan, Jacalyn S; Moore, Anthony N; Dash, Pramod K

2018-03-01

A hallmark of long-term memory formation is the requirement for protein synthesis. Administration of protein synthesis inhibitors impairs long-term memory formation without influencing short-term memory. Rapamycin is a specific inhibitor of target of rapamycin complex 1 (TORC1) that has been shown to block protein synthesis and impair long-term memory. In addition to regulating protein synthesis, TORC1 also phosphorylates Unc-51-like autophagy activating kinase-1 (Ulk-1) to suppress autophagy. As autophagy can be activated by rapamycin (and rapamycin inhibits long-term memory), our aim was to test the hypothesis that autophagy inhibitors would enhance long-term memory. To examine if learning alters autophagosome number, we used male reporter mice carrying the GFP-LC3 transgene. Using these mice, we observed that training in the Morris water maze task increases the number of autophagosomes, a finding contrary to our expectations. For learning and memory studies, male Long Evans rats were used due to their relatively larger size (compared to mice), making it easier to perform intrahippocampal infusions in awake, moving animals. When the autophagy inhibitors 3-methyladenine (3-MA) or Spautin-1 were administered bilaterally into the hippocampii prior to training in the Morris water maze task, the drugs did not alter learning. In contrast, when memory was tested 24 hours later by a probe trial, significant impairments were observed. In addition, intrahippocampal infusion of an autophagy activator peptide (TAT-Beclin-1) improved long-term memory. These results indicate that autophagy is not necessary for learning, but is required for long-term memory formation. © 2017 Wiley Periodicals, Inc.

False Memories and Free Speech: Is Scientific Debate Being Suppressed?

PubMed Central

Brewin, Chris R.

2016-01-01

Summary Commentators have raised important points, including the relative contribution of false beliefs versus false memories and the issue of how findings in the laboratory can be generalized to the real world, which we have addressed here. However, some of the commentaries misrepresent what we said, make criticisms that are unfounded, or imply that our article should not have been published in Applied Cognitive Psychology. We relate these responses to a more general literature on the suppression of unwanted scientific findings and suggest that the study of false memory would be better served by more openness to alternative perspectives. Copyright © 2016 The Authors Applied Cognitive Psychology Published by John Wiley & Sons Ltd PMID:28163370

Rewriting My Autobiography: The Legal and Ethical Implications of Memory-Dampening Agents

ERIC Educational Resources Information Center

Aoki, Cynthia R. A.

2008-01-01

The formation and recall of memories are fundamental aspects of life and help preserve the complex collection of experiences that provide us with a sense of identity and autonomy. Scientists have recently started to investigate pharmacological agents that inhibit or "dampen" the strength of memory formation and recall. The development of…

Electrolytic lesions of the bilateral ventrolateral orbital cortex inhibit methamphetamine-associated contextual memory formation in rats.

PubMed

Zhao, Yan; Liu, Peng; Chu, Zheng; Liu, Fei; Han, Wei; Xun, Xi; Dang, Yong-Hui

2015-10-22

The memories that are formed between rewarding and drug-associated contextual cues have been suggested to contribute to drug addiction relapse. Recent evidence has indicated that the ventrolateral orbital cortex (VLO) plays important roles in reward-based learning and reversal learning. However, whether the VLO is required for methamphetamine-induced contextual memory formation is not well understood. In the present study, a three-phase methamphetamine-induced conditioned place preference (CPP) model was used to investigate the effects of VLO lesions on the formation of drug-associated contextual memories in rats. We found that the VLO lesions themselves elicited no observable effects on place preferences. However, the VLO lesions delayed the acquisition and extinction phases of CPP without affecting the expression level. Furthermore, the VLO lesions did not have an obvious influence on CPP reinstatement. These results indicate that electrolytic lesions of the bilateral ventrolateral orbital cortex can inhibit the formation of methamphetamine-induced contextual memories in rats. Moreover, VLO may not be critically involved in memory storage and retrieval. Copyright © 2015 Elsevier B.V. All rights reserved.

BAF53b, a Neuron-Specific Nucleosome Remodeling Factor, Is Induced after Learning and Facilitates Long-Term Memory Consolidation.

PubMed

Yoo, Miran; Choi, Kwang-Yeon; Kim, Jieun; Kim, Mujun; Shim, Jaehoon; Choi, Jun-Hyeok; Cho, Hye-Yeon; Oh, Jung-Pyo; Kim, Hyung-Su; Kaang, Bong-Kiun; Han, Jin-Hee

2017-03-29

Although epigenetic mechanisms of gene expression regulation have recently been implicated in memory consolidation and persistence, the role of nucleosome-remodeling is largely unexplored. Recent studies show that the functional loss of BAF53b, a postmitotic neuron-specific subunit of the BAF nucleosome-remodeling complex, results in the deficit of consolidation of hippocampus-dependent memory and cocaine-associated memory in the rodent brain. However, it is unclear whether BAF53b expression is regulated during memory formation and how BAF53b regulates fear memory in the amygdala, a key brain site for fear memory encoding and storage. To address these questions, we used viral vector approaches to either decrease or increase BAF53b function specifically in the lateral amygdala of adult mice in auditory fear conditioning paradigm. Knockdown of Baf53b before training disrupted long-term memory formation with no effect on short-term memory, basal synaptic transmission, and spine structures. We observed in our qPCR analysis that BAF53b was induced in the lateral amygdala neurons at the late consolidation phase after fear conditioning. Moreover, transient BAF53b overexpression led to persistently enhanced memory formation, which was accompanied by increase in thin-type spine density. Together, our results provide the evidence that BAF53b is induced after learning, and show that such increase of BAF53b level facilitates memory consolidation likely by regulating learning-related spine structural plasticity. SIGNIFICANCE STATEMENT Recent works in the rodent brain begin to link nucleosome remodeling-dependent epigenetic mechanism to memory consolidation. Here we show that BAF53b, an epigenetic factor involved in nucleosome remodeling, is induced in the lateral amygdala neurons at the late phase of consolidation after fear conditioning. Using specific gene knockdown or overexpression approaches, we identify the critical role of BAF53b in the lateral amygdala neurons for memory consolidation during long-term memory formation. Our results thus provide an idea about how nucleosome remodeling can be regulated during long-term memory formation and contributes to the permanent storage of associative fear memory in the lateral amygdala, which is relevant to fear and anxiety-related mental disorders. Copyright © 2017 the authors 0270-6474/17/373686-12$15.00/0.

Factors affecting reorganisation of memory encoding networks in temporal lobe epilepsy

PubMed Central

Sidhu, M.K.; Stretton, J.; Winston, G.P.; Symms, M.; Thompson, P.J.; Koepp, M.J.; Duncan, J.S.

2015-01-01

Summary Aims In temporal lobe epilepsy (TLE) due to hippocampal sclerosis reorganisation in the memory encoding network has been consistently described. Distinct areas of reorganisation have been shown to be efficient when associated with successful subsequent memory formation or inefficient when not associated with successful subsequent memory. We investigated the effect of clinical parameters that modulate memory functions: age at onset of epilepsy, epilepsy duration and seizure frequency in a large cohort of patients. Methods We studied 53 patients with unilateral TLE and hippocampal sclerosis (29 left). All participants performed a functional magnetic resonance imaging memory encoding paradigm of faces and words. A continuous regression analysis was used to investigate the effects of age at onset of epilepsy, epilepsy duration and seizure frequency on the activation patterns in the memory encoding network. Results Earlier age at onset of epilepsy was associated with left posterior hippocampus activations that were involved in successful subsequent memory formation in left hippocampal sclerosis patients. No association of age at onset of epilepsy was seen with face encoding in right hippocampal sclerosis patients. In both left hippocampal sclerosis patients during word encoding and right hippocampal sclerosis patients during face encoding, shorter duration of epilepsy and lower seizure frequency were associated with medial temporal lobe activations that were involved in successful memory formation. Longer epilepsy duration and higher seizure frequency were associated with contralateral extra-temporal activations that were not associated with successful memory formation. Conclusion Age at onset of epilepsy influenced verbal memory encoding in patients with TLE due to hippocampal sclerosis in the speech-dominant hemisphere. Shorter duration of epilepsy and lower seizure frequency were associated with less disruption of the efficient memory encoding network whilst longer duration and higher seizure frequency were associated with greater, inefficient, extra-temporal reorganisation. PMID:25616449

Stress in the zoo: Tracking the impact of stress on memory formation over time.

PubMed

Vogel, Susanne; Schwabe, Lars

2016-09-01

Although stress is well known to modulate human memory, precisely how memory formation is altered by a stressful encounter remains unclear. Stress effects on cognition are mainly mediated by the rapidly acting sympathetic nervous system, resulting in the release of catecholamines, and the slower acting hypothalamus-pituitary-adrenal axis secreting cortisol, which induces its effects on cognition through fast, non-genomic actions and delayed, genomic actions. Importantly, these different waves of the physiological stress response are thought to dynamically alter neural processing in brain regions important for memory such as the amygdala and the hippocampus. However, the precise time course of stress effects on memory formation is still unclear. To track the development of stress effects on memory over time, we tested individuals who underwent a stressful experience or a control procedure before a 2-h walk through a zoo, while an automatic camera continuously photographed the events they encoded. In a recognition memory test one week later, participants were presented with target photographs of their own zoo tour and lure photographs from an alternate tour. Stressed participants showed better memory for the experimental treatment than control participants, and this memory enhancement for the stressful encounter itself was directly linked to the sympathetic stress response. Moreover, stress enhanced memory for events encoded 41-65min after stressor onset, which was associated with the cortisol stress response, most likely arising from non-genomic cortisol actions. However, memory for events encoded long after the stressor, when genomic cortisol actions had most likely developed, remained unchanged. Our findings provide novel insights into how stress effects on memory formation develop over time, depending on the activity of major physiological stress response systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Histone Deacetylase HDAC4 Regulates Long-Term Memory in Drosophila

PubMed Central

Fitzsimons, Helen L.; Schwartz, Silvia; Given, Fiona M.; Scott, Maxwell J.

2013-01-01

A growing body of research indicates that pharmacological inhibition of histone deacetylases (HDACs) correlates with enhancement of long-term memory and current research is concentrated on determining the roles that individual HDACs play in cognitive function. Here, we investigate the role of HDAC4 in long-term memory formation in Drosophila. We show that overexpression of HDAC4 in the adult mushroom body, an important structure for memory formation, resulted in a specific impairment in long-term courtship memory, but had no affect on short-term memory. Overexpression of an HDAC4 catalytic mutant also abolished LTM, suggesting a mode of action independent of catalytic activity. We found that overexpression of HDAC4 resulted in a redistribution of the transcription factor MEF2 from a relatively uniform distribution through the nucleus into punctate nuclear bodies, where it colocalized with HDAC4. As MEF2 has also been implicated in regulation of long-term memory, these data suggest that the repressive effects of HDAC4 on long-term memory may be through interaction with MEF2. In the same genetic background, we also found that RNAi-mediated knockdown of HDAC4 impairs long-term memory, therefore we demonstrate that HDAC4 is not only a repressor of long-term memory, but also modulates normal memory formation. PMID:24349558

Synchrony and desynchrony in circadian clocks: impacts on learning and memory

PubMed Central

Krishnan, Harini C.

2015-01-01

Circadian clocks evolved under conditions of environmental variation, primarily alternating light dark cycles, to enable organisms to anticipate daily environmental events and coordinate metabolic, physiological, and behavioral activities. However, modern lifestyle and advances in technology have increased the percentage of individuals working in phases misaligned with natural circadian activity rhythms. Endogenous circadian oscillators modulate alertness, the acquisition of learning, memory formation, and the recall of memory with examples of circadian modulation of memory observed across phyla from invertebrates to humans. Cognitive performance and memory are significantly diminished when occurring out of phase with natural circadian rhythms. Disruptions in circadian regulation can lead to impairment in the formation of memories and manifestation of other cognitive deficits. This review explores the types of interactions through which the circadian clock modulates cognition, highlights recent progress in identifying mechanistic interactions between the circadian system and the processes involved in memory formation, and outlines methods used to remediate circadian perturbations and reinforce circadian adaptation. PMID:26286653

Memory for Lectures: How Lecture Format Impacts the Learning Experience

PubMed Central

Varao-Sousa, Trish L.; Kingstone, Alan

2015-01-01

The present study investigated what impact the presentation style of a classroom lecture has on memory, mind wandering, and the subjective factors of interest and motivation. We examined if having a professor lecturing live versus on video alters the learning experience of the students in the classroom. During the lectures, students were asked to report mind wandering and later complete a memory test. The lecture format was manipulated such that all the students received two lectures, one live and one a pre-recorded video. Results indicate that lecture format affected memory performance but not mind wandering, with enhanced memory in the live lectures. Additionally, students reported greater interest and motivation in the live lectures. Given that a single change to the classroom environment, professor presence, impacted memory performance, as well as motivation and interest, the present results have several key implications for technology-based integrations into higher education classrooms. PMID:26561235

Memory for Lectures: How Lecture Format Impacts the Learning Experience.

PubMed

Varao-Sousa, Trish L; Kingstone, Alan

2015-01-01

The present study investigated what impact the presentation style of a classroom lecture has on memory, mind wandering, and the subjective factors of interest and motivation. We examined if having a professor lecturing live versus on video alters the learning experience of the students in the classroom. During the lectures, students were asked to report mind wandering and later complete a memory test. The lecture format was manipulated such that all the students received two lectures, one live and one a pre-recorded video. Results indicate that lecture format affected memory performance but not mind wandering, with enhanced memory in the live lectures. Additionally, students reported greater interest and motivation in the live lectures. Given that a single change to the classroom environment, professor presence, impacted memory performance, as well as motivation and interest, the present results have several key implications for technology-based integrations into higher education classrooms.

Learning and memory: Steroids and epigenetics.

PubMed

Colciago, Alessandra; Casati, Lavinia; Negri-Cesi, Paola; Celotti, Fabio

2015-06-01

Memory formation and utilization is a complex process involving several brain structures in conjunction as the hippocampus, the amygdala and the adjacent cortical areas, usually defined as medial temporal lobe structures (MTL). The memory processes depend on the formation and modulation of synaptic connectivity affecting synaptic strength, synaptic plasticity and synaptic consolidation. The basic neurocognitive mechanisms of learning and memory are shortly recalled in the initial section of this paper. The effect of sex hormones (estrogens, androgens and progesterone) and of adrenocortical steroids on several aspects of memory processes are then analyzed on the basis of animal and human studies. A specific attention has been devoted to the different types of steroid receptors (membrane or nuclear) involved and on local metabolic transformations when required. The review is concluded by a short excursus on the steroid activated epigenetic mechanisms involved in memory formation. Copyright © 2015 Elsevier Ltd. All rights reserved.

SODR Memory Control Buffer Control ASIC

NASA Technical Reports Server (NTRS)

Hodson, Robert F.

1994-01-01

The Spacecraft Optical Disk Recorder (SODR) is a state of the art mass storage system for future NASA missions requiring high transmission rates and a large capacity storage system. This report covers the design and development of an SODR memory buffer control applications specific integrated circuit (ASIC). The memory buffer control ASIC has two primary functions: (1) buffering data to prevent loss of data during disk access times, (2) converting data formats from a high performance parallel interface format to a small computer systems interface format. Ten 144 p in, 50 MHz CMOS ASIC's were designed, fabricated and tested to implement the memory buffer control function.

The Role of Lactate-Mediated Metabolic Coupling between Astrocytes and Neurons in Long-Term Memory Formation

PubMed Central

Steinman, Michael Q.; Gao, Virginia; Alberini, Cristina M.

2016-01-01

Long-term memory formation, the ability to retain information over time about an experience, is a complex function that affects multiple behaviors, and is an integral part of an individual’s identity. In the last 50 years many scientists have focused their work on understanding the biological mechanisms underlying memory formation and processing. Molecular studies over the last three decades have mostly investigated, or given attention to, neuronal mechanisms. However, the brain is composed of different cell types that, by concerted actions, cooperate to mediate brain functions. Here, we consider some new insights that emerged from recent studies implicating astrocytic glycogen and glucose metabolisms, and particularly their coupling to neuronal functions via lactate, as an essential mechanism for long-term memory formation. PMID:26973477

Dorsal medial prefrontal cortex contributes to conditioned taste aversion memory consolidation and retrieval.

PubMed

Gonzalez, Maria Carolina; Villar, Maria Eugenia; Igaz, Lionel M; Viola, Haydée; Medina, Jorge H

2015-12-01

The medial prefrontal cortex (mPFC) is known for its role in decision making and memory processing, including the participation in the formation of extinction memories. However, little is known regarding its contribution to aversive memory consolidation. Here we demonstrate that neural activity and protein synthesis are required in the dorsal mPFC for memory formation of a conditioned taste aversion (CTA) task and that this region is involved in the retrieval of recent and remote long-term CTA memory. In addition, both NMDA receptor and CaMKII activity in dorsal mPFC are needed for CTA memory consolidation, highlighting the complexity of mPFC functions. Copyright © 2015 Elsevier Inc. All rights reserved.

Spermidine boosts autophagy to protect from synapse aging.

PubMed

Bhukel, Anuradha; Madeo, Frank; Sigrist, Stephan J

2017-02-01

All animals form memories to adapt their behavior in a context-dependent manner. With increasing age, however, forming new memories becomes less efficient. While synaptic plasticity promotes memory formation, the etiology of age-induced memory formation remained enigmatic. Previous work showed that simple feeding of polyamine spermidine protects from age-induced memory impairment in Drosophila. Most recent work now shows that spermidine operates directly at synapses, allowing for an autophagy-dependent homeostatic regulation of presynaptic specializations. How exactly autophagic regulations intersect with synaptic plasticity should be an interesting subject for future research.

Impact of emotionality on memory and meta-memory in schizophrenia using video sequences.

PubMed

Peters, Maarten J V; Hauschildt, Marit; Moritz, Steffen; Jelinek, Lena

2013-03-01

A vast amount of memory and meta-memory research in schizophrenia shows that these patients perform worse on memory accuracy and hold false information with strong conviction compared to healthy controls. So far, studies investigating these effects mainly used traditional static stimulus material like word lists or pictures. The question remains whether these memory and meta-memory effects are also present in (1) more near-life dynamic situations (i.e., using standardized videos) and (2) whether emotionality has an influence on memory and meta-memory deficits (i.e., response confidence) in schizophrenia compared to healthy controls. Twenty-seven schizophrenia patients and 24 healthy controls were administered a newly developed emotional video paradigm with five videos differing in emotionality (positive, two negative, neutral, and delusional related). After each video, a recognition task required participants to make old-new discriminations along with confidence ratings, investigating memory accuracy and meta-memory deficits in more dynamic settings. For all but the positively valenced video, patients recognized fewer correct items compared to healthy controls, and did not differ with regard to the number of false memories for related items. In line with prior findings, schizophrenia patients showed more high-confident responses for misses and false memories for related items but displayed underconfidence for hits when compared to healthy controls, independent of emotionality. Limited sample size and control group; combined valence and arousal indicator for emotionality; general psychopathology indicator. Emotionality differentially moderated memory accuracy, biases in schizophrenia patients compared to controls. Moreover, the meta-memory deficits identified in static paradigms also manifest in more dynamic settings near-life settings and seem to be independent of emotionality. Copyright © 2012 Elsevier Ltd. All rights reserved.

Valence and the development of immediate and long-term false memory illusions.

PubMed

Howe, Mark L; Candel, Ingrid; Otgaar, Henry; Malone, Catherine; Wimmer, Marina C

2010-01-01

Across five experiments we examined the role of valence in children's and adults' true and false memories. Using the Deese/Roediger-McDermott paradigm and either neutral or negative-emotional lists, both adults' (Experiment 1) and children's (Experiment 2) true recall and recognition was better for neutral than negative items, and although false recall was also higher for neutral items, false recognition was higher for negative items. The last three experiments examined adults' (Experiment 3) and children's (Experiments 4 and 5) 1-week long-term recognition of neutral and negative-emotional information. The results replicated the immediate recall and recognition findings from the first two experiments. More important, these experiments showed that although true recognition decreased over the 1-week interval, false recognition of neutral items remained unchanged whereas false recognition of negative-emotional items increased. These findings are discussed in terms of theories of emotion and memory as well as their forensic implications.

Estradiol replacement enhances fear memory formation, impairs extinction and reduces COMT expression levels in the hippocampus of ovariectomized female mice.

PubMed

McDermott, Carmel M; Liu, Dan; Ade, Catherine; Schrader, Laura A

2015-02-01

Females experience depression, posttraumatic stress disorder (PTSD), and anxiety disorders at approximately twice the rate of males, but the mechanisms underlying this difference remain undefined. The effect of sex hormones on neural substrates presents a possible mechanism. We investigated the effect of ovariectomy at two ages, before puberty and in adulthood, and 17β-estradiol (E2) replacement administered chronically in drinking water on anxiety level, fear memory formation, and extinction. Based on previous studies, we hypothesized that estradiol replacement would impair fear memory formation and enhance extinction rate. Females, age 4 weeks and 10 weeks, were divided randomly into 4 groups; sham surgery, OVX, OVX+low E2 (200nM), and OVX+high E2 (1000nM). Chronic treatment with high levels of E2 significantly increased anxiety levels measured in the elevated plus maze. In both age groups, high levels of E2 significantly increased contextual fear memory but had no effect on cued fear memory. In addition, high E2 decreased the rate of extinction in both ages. Finally, catechol-O-methyltransferase (COMT) is important for regulation of catecholamine levels, which play a role in fear memory formation and extinction. COMT expression in the hippocampus was significantly reduced by high E2 replacement, implying increased catecholamine levels in the hippocampus of high E2 mice. These results suggest that estradiol enhanced fear memory formation, and inhibited fear memory extinction, possibly stabilizing the fear memory in female mice. This study has implications for a neurobiological mechanism for PTSD and anxiety disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

Congenital blindness improves semantic and episodic memory.

PubMed

Pasqualotto, Achille; Lam, Jade S Y; Proulx, Michael J

2013-05-01

Previous studies reported that congenitally blind people possess superior verb-generation skills. Here we tested the impact of blindness on capacity and the fidelity of semantic memory by using a false memory paradigm. In the Deese-Roediger-McDermott paradigm, participants study lists of words that are all semantically related to a lure that is not presented. Subsequently, participants frequently recall the missing lure. We found that congenitally blind participants have enhanced memory performance for recalling the presented words and reduced false memories for the lure. The dissociation of memory capacity and fidelity provides further evidence for enhanced verbal ability in the blind, supported by their broader structural and functional brain reorganisation. Copyright © 2013 Elsevier B.V. All rights reserved.

Effects of the swimming exercise on the consolidation and persistence of auditory and contextual fear memory.

PubMed

Faria, Rodolfo Souza; Gutierres, Luís Felipe Soares; Sobrinho, Fernando César Faria; Miranda, Iris do Vale; Reis, Júlia Dos; Dias, Elayne Vieira; Sartori, Cesar Renato; Moreira, Dalmo Antonio Ribeiro

2016-08-15

Exposure to negative environmental events triggers defensive behavior and leads to the formation of aversive associative memory. Cellular and molecular changes in the central nervous system underlie this memory formation, as well as the associated behavioral changes. In general, memory process is established in distinct phases such as acquisition, consolidation, evocation, persistence, and extinction of the acquired information. After exposure to a particular event, early changes in involved neural circuits support the memory consolidation, which corresponds to the short-term memory. Re-exposure to previously memorized events evokes the original memory, a process that is considered essential for the reactivation and consequent persistence of memory, ensuring that long-term memory is established. Different environmental stimuli may modulate the memory formation process, as well as their distinct phases. Among the different environmental stimuli able of modulating memory formation is the physical exercise which is a potent modulator of neuronal activity. There are many studies showing that physical exercise modulates learning and memory processes, mainly in the consolidation phase of the explicit memory. However, there are few reports in the literature regarding the role of physical exercise in implicit aversive associative memory, especially at the persistence phase. Thus, the present study aimed to investigate the relationship between swimming exercise and the consolidation and persistence of contextual and auditory-cued fear memory. Male Wistar rats were submitted to sessions of swimming exercise five times a week, over six weeks. After that, the rats were submitted to classical aversive conditioning training by a pairing tone/foot shock paradigm. Finally, rats were evaluated for consolidation and persistence of fear memory to both auditory and contextual cues. Our results demonstrate that classical aversive conditioning with tone/foot shock pairing induced consolidation as well as persistence of conditioned fear memory. In addition, rats submitted to swimming exercise over six weeks showed an improved performance in the test of auditory-cued fear memory persistence, but not in the test of contextual fear memory persistence. Moreover, no significant effect from swimming exercise was observed on consolidation of both contextual and auditory fear memory. So, our study, revealing the effect of the swimming exercise on different stages of implicit memory of tone/foot shock conditioning, contributes to and complements the current knowledge about the environmental modulation of memory process. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Anchoring effects in the development of false childhood memories.

PubMed

Wade, Kimberley A; Garry, Maryanne; Nash, Robert A; Harper, David N

2010-02-01

When people receive descriptions or doctored photos of events that never happened, they often come to remember those events. But if people receive both a description and a doctored photo, does the order in which they receive the information matter? We asked people to consider a description and a doctored photograph of a childhood hot air balloon ride, and we varied which medium they saw first. People who saw a description first reported more false images and memories than did people who saw a photo first, a result that fits with an anchoring account of false childhood memories.

The effects of refreshing and elaboration on working memory performance, and their contributions to long-term memory formation.

PubMed

Bartsch, Lea M; Singmann, Henrik; Oberauer, Klaus

2018-03-19

Refreshing and elaboration are cognitive processes assumed to underlie verbal working-memory maintenance and assumed to support long-term memory formation. Whereas refreshing refers to the attentional focussing on representations, elaboration refers to linking representations in working memory into existing semantic networks. We measured the impact of instructed refreshing and elaboration on working and long-term memory separately, and investigated to what extent both processes are distinct in their contributions to working as well as long-term memory. Compared with a no-processing baseline, immediate memory was improved by repeating the items, but not by refreshing them. There was no credible effect of elaboration on working memory, except when items were repeated at the same time. Long-term memory benefited from elaboration, but not from refreshing the words. The results replicate the long-term memory benefit for elaboration, but do not support its beneficial role for working memory. Further, refreshing preserves immediate memory, but does not improve it beyond the level achieved without any processing.

Children's False Memory and True Disclosure in the Face of Repeated Questions

ERIC Educational Resources Information Center

Schaaf, Jennifer M.; Alexander, Kristen Weede; Goodman, Gail S.

2008-01-01

The current study was designed to investigate children's memory and suggestibility for events differing in valence (positive or negative) and veracity (true or false). A total of 82 3- and 5-year-olds were asked repeated questions about true and false events, either in a grouped order (i.e., all questions about a certain event asked consecutively)…

False recollection of emotional pictures in Alzheimer's disease.

PubMed

Gallo, David A; Foster, Katherine T; Wong, Jessica T; Bennett, David A

2010-10-01

Alzheimer's Disease (AD) can reduce the effects of emotional content on memory for studied pictures, but less is known about false memory. In healthy adults, emotionally arousing pictures can be more susceptible to false memory effects than neutral pictures, potentially because emotional pictures share conceptual similarities that cause memory confusions. We investigated these effects in AD patients and healthy controls. Participants studied pictures and their verbal labels, and then picture recollection was tested using verbal labels as retrieval cues. Some of the test labels had been associated with a picture at study, whereas other had not. On this picture recollection test, we found that both AD patients and controls incorrectly endorsed some of the test labels that had not been studied with pictures. These errors were associated with medium to high levels of confidence, indicating some degree of false recollection. Critically, these false recollection judgments were greater for emotional compared to neutral items, especially for positively valenced items, in both AD patients and controls. Dysfunction of the amygdala and hippocampus in early AD may impair recollection, but AD did not disrupt the effect of emotion on false recollection judgments. Copyright © 2010 Elsevier Ltd. All rights reserved.

Output Position and Word Relatedness Effects in a DRM Paradigm: Support for a Dual-Retrieval Process Theory of Free Recall and False Memories

ERIC Educational Resources Information Center

Barnhardt, T. M.; Choi, H.; Gerkens, D. R.; Smith, S. M.

2006-01-01

Five experiments investigated predictions--derived from a dual-retrieval process approach to free recall (Brainerd, C. J., Wright, R., Reyna, V. F., & Payne, D. G. (2002). Dual-retrieval processes in free and associative recall. Journal of Memory and Language, 46, 120-152.)--about false memories in a DRM-like paradigm. In all the experiments, the…

Sex-Dependent Up-Regulation of Two Splicing Factors, Psf and Srp20, during Hippocampal Memory Formation

ERIC Educational Resources Information Center

Antunes-Martins, Ana; Mizuno, Keiko; Irvine, Elaine E.; Lepicard, Eve M.; Giese, K. Peter

2007-01-01

Gene transcription is required for long-term memory (LTM) formation. LTM formation is impaired in a male-specific manner in mice lacking either of the two Ca[superscript 2+] / calmodulin-dependent kinase kinase ("Camkk") genes. Since altered transcription was suggested to cause these impairments in LTM formation, we used microarrays to screen for…

Astrocyte-neuron lactate transport is required for long-term memory formation

PubMed Central

Suzuki, Akinobu; Stern, Sarah A.; Bozdagi, Ozlem; Huntley, George W.; Walker, Ruth H.; Magistretti, Pierre J.; Alberini, Cristina M.

2011-01-01

SUMMARY We report that in the rat hippocampus learning leads to a significant increase in extracellular lactate levels, which derive from glycogen, an energy reserve selectively localized in astrocytes. Astrocytic glycogen breakdown and lactate release are essential for long-term but not short-term memory formation, and for the maintenance of long-term potentiation (LTP) of synaptic strength elicited in-vivo. Disrupting the expression of the astrocytic lactate transporters monocarboxylate transporter 4 (MCT4) or MCT1 causes amnesia, which, like LTP impairment, is rescued by lactate but not equicaloric glucose. Disrupting the expression of the neuronal lactate transporter MCT2 also leads to amnesia that is unaffected by either L-lactate or glucose, suggesting that lactate import into neurons is necessary for long-term memory. Glycogenolysis and astrocytic lactate transporters are also critical for the induction of molecular changes required for memory formation, including the induction of phospho-CREB, Arc and phospho-cofilin. We conclude that astrocyte-neuron lactate transport is required for long-term memory formation. PMID:21376239

Deleting HDAC3 Rescues Long-Term Memory Impairments Induced by Disruption of the Neuron-Specific Chromatin Remodeling Subunit BAF53b

ERIC Educational Resources Information Center

Shu, Guanhua; Kramár, Enikö A.; López, Alberto J.; Huynh, Grace; Wood, Marcelo A.; Kwapis, Janine L.

2018-01-01

Multiple epigenetic mechanisms, including histone acetylation and nucleosome remodeling, are known to be involved in long-term memory formation. Enhancing histone acetylation by deleting histone deacetylases, like HDAC3, typically enhances long-term memory formation. In contrast, disrupting nucleosome remodeling by blocking the neuron-specific…

Activation of Midbrain Structures by Associative Novelty and the Formation of Explicit Memory in Humans

ERIC Educational Resources Information Center

Schott, Bjorn H.; Sellner, Daniela B.; Lauer, Corinna-J.; Habib, Reza; Frey, Julietta U.; Guderian, Sebastian; Heinze, Hans-Jochen; Duzel, Emrah

2004-01-01

Recent evidence suggests a close functional relationship between memory formation in the hippocampus and dopaminergic neuromodulation originating in the ventral tegmental area and medial substantia nigra of the midbrain. Here we report midbrain activation in two functional MRI studies of visual memory in healthy young adults. In the first study,…

Subregion-Specific p300 Conditional Knock-Out Mice Exhibit Long-Term Memory Impairments

ERIC Educational Resources Information Center

Oliveira, Ana M. M.; Estevez, Marcel A.; Hawk, Joshua D.; Grimes, Shannon; Brindle, Paul K.; Abel, Ted

2011-01-01

Histone acetylation plays a critical role during long-term memory formation. Several studies have demonstrated that the histone acetyltransferase (HAT) CBP is required during long-term memory formation, but the involvement of other HAT proteins has not been extensively investigated. The HATs CBP and p300 have at least 400 described interacting…

Interaction of Inhibitory and Facilitatory Effects of Conditioning Trials on Long-Term Memory Formation

ERIC Educational Resources Information Center

Hosono, Shouhei; Matsumoto, Yukihisa; Mizunami, Makoto

2016-01-01

Animals learn through experience and consolidate the memories into long-time storage. Conditioning parameters to induce protein synthesis-dependent long-term memory (LTM) have been the subject of extensive studies in many animals. Here we found a case in which a conditioning trial inhibits or facilitates LTM formation depending on the intervals…

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

PubMed

Smith, Amy M; Gallo, David A; Barber, Sarah J; Maddox, Keith B; Thomas, Ayanna K

2017-08-01

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. 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. 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. 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. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

CREB binding protein is required for both short-term and long-term memory formation.

PubMed

Chen, Guiquan; Zou, Xiaoyan; Watanabe, Hirotaka; van Deursen, Jan M; Shen, Jie

2010-09-29

CREB binding protein (CBP) is a transcriptional coactivator with histone acetyltransferase activity. Our prior study suggested that CBP might be a key target of presenilins in the regulation of memory formation and neuronal survival. To elucidate the role of CBP in the adult brain, we generated conditional knock-out (cKO) mice in which CBP is completely inactivated in excitatory neurons of the postnatal forebrain. Histological analysis revealed normal neuronal morphology and absence of age-dependent neuronal degeneration in the CBP cKO cerebral cortex. CBP cKO mice exhibited robust impairment in the formation of spatial, associative, and object-recognition memory. In addition to impaired long-term memory, CBP cKO mice also displayed deficits in short-term associative and object-recognition memory. Administration of a histone deacetylase inhibitor, trichostatin A, rescued the reduction of acetylated histones in the CBP cKO cortex but failed to rescue either short- or long-term memory deficits, suggesting that the memory impairment may not be caused by general reduction of histone acetyltransferase activity in CBP cKO mice. Further microarray and Western analysis showed decreased expression of calcium-calmodulin-dependent kinase isoforms and NMDA and AMPA receptor subunits in the cerebral cortex of CBP cKO mice. Collectively, these findings suggest a crucial role for CBP in the formation of both short- and long-term memory.

Can False Memories Prime Problem Solutions for Healthy Older Adults and those with Alzheimer 's Disease?

PubMed

Akhtar, Shazia; Howe, Mark L; Hoepstine, Kedron

2018-06-05

Recent research has shown that false memories can have a positive consequence on human cognition in both children and young adults. The present experiment investigated whether false memories could have similar positive effects by priming solutions to insight-based problems in healthy older adults and people with Alzheimer's disease. Participants were asked to solve compound remote associate task (CRAT) problems, half of which had been preceded by the presentation of Deese/Roediger-McDermott (DRM) lists whose critical lures were also the solutions to those problems. The results showed that regardless of cognitive ability, when the critical lure was falsely recognized, CRAT problems were solved more often and reliably faster than problems that were not primed by a DRM list. When the critical lure was not falsely recognized, CRAT problem solution rates and times were no different from when there was no DRM priming. These findings are consistent with predictions from theories of associative activation and demonstrate the importance of automatic spreading activation processes in memory across the lifespan.

A flavanoid component of chocolate quickly reverses an imposed memory deficit.

PubMed

Knezevic, Bogdan; Komatsuzaki, Yoshimasa; de Freitas, Emily; Lukowiak, Ken

2016-03-01

The ability to remember is influenced by environmental and lifestyle factors, such as stress and diet. A flavanol contained in chocolate, epicatechin (Epi), has been shown to enhance long-term memory (LTM) formation in Lymnaea. Combining two stressors (low-calcium pond water and crowding) blocks learning and all forms of memory; that is, this combination of environmentally relevant stressors creates a memory-unfriendly state. We tested the hypothesis that Epi will immediately reverse the memory-unfriendly state, i.e. that snails in the memory-deficit state when trained in Epi will immediately become competent to learn and form memory. We found that Epi not only reverses the memory-deficit state but also further enhances LTM formation. Thus, a naturally occurring bioactive plant compound can overcome a memory-unfriendly state. This supports the idea that bioactive substances may mitigate memory-making deficits that, for example, occur with ageing. © 2016. Published by The Company of Biologists Ltd.

False memory and level of processing effect: an event-related potential study.

PubMed

Beato, Maria Soledad; Boldini, Angela; Cadavid, Sara

2012-09-12

Event-related potentials (ERPs) were used to determine the effects of level of processing on true and false memory, using the Deese-Roediger-McDermott (DRM) paradigm. In the DRM paradigm, lists of words highly associated to a single nonpresented word (the 'critical lure') are studied and, in a subsequent memory test, critical lures are often falsely remembered. Lists with three critical lures per list were auditorily presented here to participants who studied them with either a shallow (saying whether the word contained the letter 'o') or a deep (creating a mental image of the word) processing task. Visual presentation modality was used on a final recognition test. True recognition of studied words was significantly higher after deep encoding, whereas false recognition of nonpresented critical lures was similar in both experimental groups. At the ERP level, true and false recognition showed similar patterns: no FN400 effect was found, whereas comparable left parietal and late right frontal old/new effects were found for true and false recognition in both experimental conditions. Items studied under shallow encoding conditions elicited more positive ERP than items studied under deep encoding conditions at a 1000-1500 ms interval. These ERP results suggest that true and false recognition share some common underlying processes. Differential effects of level of processing on true and false memory were found only at the behavioral level but not at the ERP level.

Strong homeostatic TCR signals induce formation of self-tolerant virtual memory CD8 T cells.

PubMed

Drobek, Ales; Moudra, Alena; Mueller, Daniel; Huranova, Martina; Horkova, Veronika; Pribikova, Michaela; Ivanek, Robert; Oberle, Susanne; Zehn, Dietmar; McCoy, Kathy D; Draber, Peter; Stepanek, Ondrej

2018-05-11

Virtual memory T cells are foreign antigen-inexperienced T cells that have acquired memory-like phenotype and constitute 10-20% of all peripheral CD8 + T cells in mice. Their origin, biological roles, and relationship to naïve and foreign antigen-experienced memory T cells are incompletely understood. By analyzing T-cell receptor repertoires and using retrogenic monoclonal T-cell populations, we demonstrate that the virtual memory T-cell formation is a so far unappreciated cell fate decision checkpoint. We describe two molecular mechanisms driving the formation of virtual memory T cells. First, virtual memory T cells originate exclusively from strongly self-reactive T cells. Second, the stoichiometry of the CD8 interaction with Lck regulates the size of the virtual memory T-cell compartment via modulating the self-reactivity of individual T cells. Although virtual memory T cells descend from the highly self-reactive clones and acquire a partial memory program, they are not more potent in inducing experimental autoimmune diabetes than naïve T cells. These data underline the importance of the variable level of self-reactivity in polyclonal T cells for the generation of functional T-cell diversity. © 2018 The Authors. Published under the terms of the CC BY 4.0 license.

Memory, reconsolidation and extinction in Lymnaea require the soma of RPeD1.

PubMed

Sangha, Susan; Varshney, Nishi; Fras, Mary; Smyth, Kim; Rosenegger, David; Parvez, Kashif; Sadamoto, Hisayo; Lukowiak, Ken

2004-01-01

The central pattern generator (CPG) that drives aerial respiratory behaviour in Lymnaea consists of 3 neurons. One of these, RPeD1--the cell that initiates activity in the circuit, plays an absolutely necessary role as a site for memory formation, memory reconsolidation, and extinction. Using an operant conditioning training procedure that results in a long-term non-declarative memory (LTM), we decrease the occurrence of aerial respiratory behaviour. Since snails can still breathe cutaneously learning this procedure is not harmful. Concomitant with behavioural memory are changes in the spiking activity of RPeD1. Going beyond neural correlates of memory we directly show that RPeD1 is a necessary site for LTM formation. Expanding on this finding we show that this neuron is also a necessary site for memory reconsolidation and 'Pavlovian' extinction. As far as we can determine, this is the first time a single neuron has been shown to be a necessary site for these different aspects memory. RPeD1 is thus a key neuron mediating different hierarchical aspects of memory. We are now in a position to determine the necessary neuronal, molecular and proteomic events in this neuron that are causal to memory formation, reconsolidation and extinction.

How mood challenges emotional memory formation: an fMRI investigation.

PubMed

Fitzgerald, Daniel A; Arnold, Jennifer F; Becker, Eni S; Speckens, Anne E M; Rinck, Mike; Rijpkema, Mark; Fernández, Guillén; Tendolkar, Indira

2011-06-01

Experimental mood manipulations and functional magnetic resonance imaging (fMRI) provide a unique opportunity for examining the neural correlates of mood-congruent memory formation. While prior studies in mood-disorder patients point to the medial temporal lobe in the genesis of mood-congruent memory (MCM) bias, the interaction between mood and emotional memory formation has not been investigated in healthy participants. In particular it remains unclear how regulatory structures in the pre-frontal cortex may be involved in mediating this phenomenon. In this study, event-related fMRI was performed on 20 healthy participants using a full-factorial, within-subjects repeated-measures design to examine how happy and sad moods impact memory for valenced stimuli (positive, negative and neutral words). Main effects of mood, stimulus valence and memory were examined as was activity related to successful memory formation during congruent and in-congruent moods. Behavioral results confirm an MCM bias while imaging results show amygdala and hippocampal engagement in a global mood and successful recall, respectively. MCM formation was characterized by increased activity during mood-congruent encoding of negative words in the orbito-frontal cortex (OFC) and for mood-incongruent processing of negative words in medial- and inferior-frontal gyri (MFG/IFG). These findings indicate that different pre-frontal regions facilitate mood-congruent and incongruent encoding of successfully recalled negative words at the time of learning, with OFC enhancing congruency and the left IFG and MFG helping overcome semantic incongruities between mood and stimulus valence. Copyright © 2011 Elsevier Inc. All rights reserved.

Entrainment of prefrontal beta oscillations induces an endogenous echo and impairs memory formation.

PubMed

Hanslmayr, Simon; Matuschek, Jonas; Fellner, Marie-Christin

2014-04-14

Brain oscillations across all frequency bands play a key role for memory formation. Specifically, desynchronization of local neuronal assemblies in the left inferior prefrontal cortex (PFC) in the beta frequency (∼18 Hz) has been shown to be central for encoding of verbal memories. However, it remains elusive whether prefrontal beta desynchronization is causally relevant for memory formation and whether these endogenous beta oscillations can be entrained by external stimulation. By using combined EEG-TMS (transcranial magnetic stimulation), we here address these fundamental questions in human participants performing a word-list learning task. Confirming our predictions, memory encoding was selectively impaired when the left inferior frontal gyrus (IFG) was driven at beta (18.7 Hz) compared to stimulation at other frequencies (6.8 Hz and 10.7 Hz) and to ineffective sham stimulation (18.7 Hz). Furthermore, a sustained oscillatory "echo" in the left IFG, which outlasted the stimulation period by approximately 1.5 s, was observed solely after beta stimulation. The strength of this beta echo was related to memory impairment on a between-subjects level. These results show endogenous oscillatory entrainment effects and behavioral impairment selectively in beta frequency for stimulation of the left IFG, demonstrating an intimate causal relationship between prefrontal beta desynchronization and memory formation. Copyright © 2014 Elsevier Ltd. All rights reserved.

False memories and confabulation.

PubMed

Johnson, M K; Raye, C L

1998-04-01

Memory distortions range from the benign (thinking you mailed a check that you only thought about mailing), to the serious (confusing what you heard after a crime with what you actually saw), to the fantastic (claiming you piloted a spaceship). We review theoretical ideas and empirical evidence about the source monitoring processes underlying both true and false memories. Neuropsychological studies show that certain forms of brain damage (such as combined frontal and medial-temporal lesions) might result in profound source confusions, called confabulations. Neuroimaging techniques provide new evidence regarding more specific links between underlying brain mechanisms and the normal cognitive processes involved in evaluating memories. One hypothesis is that the right prefrontal cortex (PFC) subserves heuristic judgments based on easily assessed qualities (such as familiarity or perceptual detail) and the left PFC (or the right and left PFC together) subserves more systematic judgments requiring more careful analysis of memorial qualities or retrieval and evaluation of additional supporting or disconfirming information. Such heuristic and systematic processes can be disrupted not only by brain damage but also, for example, by hypnosis, social demands and motivational factors, suggesting caution in the methods used by `memory exploring' professions (therapists, police officers, lawyers, etc.) in order to avoid inducing false memories.

Memory for musical tones: the impact of tonality and the creation of false memories.

PubMed

Vuvan, Dominique T; Podolak, Olivia M; Schmuckler, Mark A

2014-01-01

Although the relation between tonality and musical memory has been fairly well-studied, less is known regarding the contribution of tonal-schematic expectancies to this relation. Three experiments investigated the influence of tonal expectancies on memory for single tones in a tonal melodic context. In the first experiment, listener responses indicated superior recognition of both expected and unexpected targets in a major tonal context than for moderately expected targets. Importantly, and in support of previous work on false memories, listener responses also revealed a higher false alarm rate for expected than unexpected targets. These results indicate roles for tonal schematic congruency as well as distinctiveness in memory for melodic tones. The second experiment utilized minor melodies, which weakened tonal expectancies since the minor tonality can be represented in three forms simultaneously. Finally, tonal expectancies were abolished entirely in the third experiment through the use of atonal melodies. Accordingly, the expectancy-based results observed in the first experiment were disrupted in the second experiment, and disappeared in the third experiment. These results are discussed in light of schema theory, musical expectancy, and classic memory work on the availability and distinctiveness heuristics.

Memory for musical tones: the impact of tonality and the creation of false memories

PubMed Central

Vuvan, Dominique T.; Podolak, Olivia M.; Schmuckler, Mark A.

2014-01-01

Although the relation between tonality and musical memory has been fairly well-studied, less is known regarding the contribution of tonal-schematic expectancies to this relation. Three experiments investigated the influence of tonal expectancies on memory for single tones in a tonal melodic context. In the first experiment, listener responses indicated superior recognition of both expected and unexpected targets in a major tonal context than for moderately expected targets. Importantly, and in support of previous work on false memories, listener responses also revealed a higher false alarm rate for expected than unexpected targets. These results indicate roles for tonal schematic congruency as well as distinctiveness in memory for melodic tones. The second experiment utilized minor melodies, which weakened tonal expectancies since the minor tonality can be represented in three forms simultaneously. Finally, tonal expectancies were abolished entirely in the third experiment through the use of atonal melodies. Accordingly, the expectancy-based results observed in the first experiment were disrupted in the second experiment, and disappeared in the third experiment. These results are discussed in light of schema theory, musical expectancy, and classic memory work on the availability and distinctiveness heuristics. PMID:24971071

False feedback and beliefs influence name recall in younger and older adults.

PubMed

Strickland-Hughes, Carla M; West, Robin Lea; Smith, Kimberly A; Ebner, Natalie C

2017-09-01

Feedback is an important self-regulatory process that affects task effort and subsequent performance. Benefits of positive feedback for list recall have been explored in research on goals and feedback, but the effect of negative feedback on memory has rarely been studied. The current research extends knowledge of memory and feedback effects by investigating face-name association memory and by examining the potential mediation of feedback effects, in younger and older adults, through self-evaluative beliefs. Beliefs were assessed before and after name recognition and name recall testing. Repeated presentation of false positive feedback was compared to false negative feedback and a no feedback condition. Results showed that memory self-efficacy declined over time for participants in the negative and no feedback conditions but was sustained for those receiving positive feedback. Furthermore, participants who received negative feedback felt older after testing than before testing. For name recall, the positive feedback group outperformed the negative feedback and no feedback groups combined, with no age interactions. The observed feedback-related effects on memory were fully mediated by changes in memory self-efficacy. These findings advance our understanding of how beliefs are related to feedback in memory and inform future studies examining the importance of self-regulation in memory.

System level mechanisms of adaptation, learning, memory formation and evolvability: the role of chaperone and other networks.

PubMed

Gyurko, David M; Soti, Csaba; Stetak, Attila; Csermely, Peter

2014-05-01

During the last decade, network approaches became a powerful tool to describe protein structure and dynamics. Here, we describe first the protein structure networks of molecular chaperones, then characterize chaperone containing sub-networks of interactomes called as chaperone-networks or chaperomes. We review the role of molecular chaperones in short-term adaptation of cellular networks in response to stress, and in long-term adaptation discussing their putative functions in the regulation of evolvability. We provide a general overview of possible network mechanisms of adaptation, learning and memory formation. We propose that changes of network rigidity play a key role in learning and memory formation processes. Flexible network topology provides ' learning-competent' state. Here, networks may have much less modular boundaries than locally rigid, highly modular networks, where the learnt information has already been consolidated in a memory formation process. Since modular boundaries are efficient filters of information, in the 'learning-competent' state information filtering may be much smaller, than after memory formation. This mechanism restricts high information transfer to the 'learning competent' state. After memory formation, modular boundary-induced segregation and information filtering protect the stored information. The flexible networks of young organisms are generally in a 'learning competent' state. On the contrary, locally rigid networks of old organisms have lost their 'learning competent' state, but store and protect their learnt information efficiently. We anticipate that the above mechanism may operate at the level of both protein-protein interaction and neuronal networks.

Theta synchronization networks emerge during human object-place memory encoding.

PubMed

Sato, Naoyuki; Yamaguchi, Yoko

2007-03-26

Recent rodent hippocampus studies have suggested that theta rhythm-dependent neural dynamics ('theta phase precession') is essential for an on-line memory formation. A computational study indicated that the phase precession enables a human object-place association memory with voluntary eye movements, although it is still an open question whether the human brain uses the dynamics. Here we elucidated subsequent memory-correlated activities in human scalp electroencephalography in an object-place association memory designed according the former computational study. Our results successfully demonstrated that subsequent memory recall is characterized by an increase in theta power and coherence, and further, that multiple theta synchronization networks emerge. These findings suggest the human theta dynamics in common with rodents in episodic memory formation.

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

PubMed

Beato, Maria Soledad; Cadavid, Sara

2016-12-01

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.

Public Attitudes on the Ethics of Deceptively Planting False Memories to Motivate Healthy Behavior

PubMed Central

Berkowitz, Shari R.; Roche, Simon

2016-01-01

Summary Researchers have proposed that planting false memories could have positive behavioral consequences. The idea of deceptively planting ‘beneficial’ false memories outside of the laboratory raises important ethical questions, but how might the general public appraise this moral dilemma? In two studies, participants from the USA and UK read about a fictional ‘false‐memory therapy’ that led people to adopt healthy behaviors. Participants then reported their attitudes toward the acceptability of this therapy, via scale‐rating (both studies) and open‐text (study 2) responses. The data revealed highly divergent responses to this contentious issue, ranging from abject horror to unqualified enthusiasm. Moreover, the responses shed light on conditions that participants believed would make the therapy less or more ethical. Whether or not deceptively planting memories outside the lab could ever be justifiable, these studies add valuable evidence to scientific and societal debates on neuroethics, whose relevance to memory science is increasingly acute. Copyright © 2016 The Authors Applied Cognitive Psychology Published by John Wiley & Sons Ltd. PMID:28111495

Rapamycin inhibits mTOR/p70S6K activation in CA3 region of the hippocampus of the rat and impairs long term memory.

PubMed

Lana, D; Di Russo, J; Mello, T; Wenk, G L; Giovannini, M G

2017-01-01

The present study was aimed at establishing whether the mTOR pathway and its downstream effector p70S6K in CA3 pyramidal neurons are under the modulation of the cholinergic input to trigger the formation of long term memories, similar to what we demonstrated in CA1 hippocampus. We performed in vivo behavioral experiments using the step down inhibitory avoidance test in adult Wistar rats to evaluate memory formation under different conditions. We examined the effects of rapamycin, an inhibitor of mTORC1 formation, scopolamine, a muscarinic receptor antagonist or mecamylamine, a nicotinic receptor antagonist, on short and long term memory formation and on the functionality of the mTOR pathway. Acquisition was conducted 30min after i.c.v. injection of rapamycin. Recall testing was performed 1h, 4h or 24h after acquisition. We found that (1) mTOR and p70S6K activation in CA3 pyramidal neurons were involved in long term memory formation; (2) rapamycin significantly inhibited mTOR and of p70S6K activation at 4h, and long term memory impairment 24h after acquisition; (3) scopolamine impaired short but not long term memory, with an early increase of mTOR/p70S6K activation at 1h followed by stabilization at longer times; (4) mecamylamine and scopolamine co-administration impaired short term memory at 1h and 4h and reduced the scopolamine-induced increase of mTOR/p70S6K activation at 1h and 4h; (5) mecamylamine and scopolamine treatment did not impair long term memory formation; (6) unexpectedly, rapamycin increased mTORC2 activation in microglial cells. Our results demonstrate that in CA3 pyramidal neurons the mTOR/p70S6K pathway is under the modulation of the cholinergic system and is involved in long-term memory encoding, and are consistent with the hypothesis that the CA3 region of the hippocampus is involved in memory mechanisms based on rapid, one-trial object-place learning and recall. Furthermore, our results are in accordance with previous reports that selective molecular mechanisms underlie either short term memory, long term memory, or both. Furthermore, our discovery that administration of rapamycin increased the activation of mTORC2 in microglial cells supports a reappraisal of the beneficial/adverse effects of rapamycin administration. Copyright © 2016 Elsevier Inc. All rights reserved.

Rapamycin inhibits mTOR/p70S6K activation in CA3 region of the hippocampus of the rat and impairs long term memory

PubMed Central

Lana, D.; Di Russo, J.; Mello, T.; Wenk, G.L.; Giovannini, M.G.

2016-01-01

The present study was aimed at establishing whether the mTOR pathway and its downstream effector p70S6K in CA3 pyramidal neurons are under the modulation of the cholinergic input to trigger the formation of long term memories, similar to what we demonstrated in CA1 hippocampus. We performed in vivo behavioral experiments using the step down inhibitory avoidance test in adult Wistar rats to evaluate memory formation under different conditions. We examined the effects of rapamycin, an inhibitor of mTORC1 formation, scopolamine, a muscarinic receptor antagonist or mecamylamine, a nicotinic receptor antagonist, on short and long term memory formation and on the functionality of the mTOR pathway. Acquisition was conducted 30 min after i.c.v. injection of rapamycin. Recall testing was performed 1h, 4h or 24h after acquisition. We found that (1) mTOR and p70S6K activation in CA3 pyramidal neurons were involved in long term memory formation; (2) rapamycin significantly inhibited mTOR and of p70S6K activation at 4h, and long term memory impairment 24h after acquisition; (3) scopolamine impaired short but not long term memory, with an early increase of mTOR/p70S6K activation at 1h followed by stabilization at longer times; (4) mecamylamine and scopolamine co-administration impaired short term memory at 1h and 4h and reduced the scopolamine-induced increase of mTOR/p70S6K activation at 1h and 4h; (5) mecamylamine and scopolamine treatment did not impair long term memory formation; (6) unexpectedly, rapamycin increased mTORC2 activation in microglial cells. Our results demonstrate that in CA3 pyramidal neurons the mTOR/p70S6K pathway is under the modulation of the cholinergic system and is involved in long-term memory encoding, and are consistent with the hypothesis that the CA3 region of the hippocampus is involved in memory mechanisms based on rapid, one-trial object–place learning and recall. Furthermore, our results are in accordance with previous reports that selective molecular mechanisms underlie either short term memory, long term memory, or both. Furthermore, our discovery that administration of rapamycin increased the activation of mTORC2 in microglial cells supports a reappraisal of the beneficial/adverse effects of rapamycin administration. PMID:27838442

Warnings reduce false memories for missing aspects of events.

PubMed

Gerrie, Matthew P; Garry, Maryanne

2011-01-01

When people see movies with some parts missing, they falsely recognize many of the missing parts later. In two experiments, we examined the effect of warnings on people's false memories for these parts. In Experiment 1, warning subjects about false recognition before the movie (forewarnings) reduced false recognition, but warning them after the movie (postwarnings) reduced false recognition to a lesser extent. In Experiment 2, the effect of the warnings depended on the nature of the missing parts. Forewarnings were more effective than postwarnings in reducing false recognition of missing noncrucial parts, but forewarnings and postwarnings were similarly effective in reducing false recognition of crucial missing parts. We use the source monitoring framework to explain our results.

Modifying Memory for a Museum Tour in Older Adults: Reactivation-Related Updating that Enhances and Distorts Memory is Reduced in Aging

PubMed Central

St Jacques, Peggy L.; Montgomery, Daniel; Schacter, Daniel L.

2015-01-01

Memory reactivation, the activation of a latent memory trace when we are reminded of a past experience, strengthens memory but can also contribute to distortions if new information present during reactivation is integrated with existing memory. In a previous study in young adults we found that the quality of memory reactivation, manipulated using the principle of encoding specificity and indexed by recollection ratings, modulated subsequent true and false memories for events experienced during a museum tour. Here, we examined age-related changes in the quality of memory reactivation on subsequent memory. Young and older adults reactivated memories for museum stops immediately followed by the presentation of a novel lure photo from an alternate tour version (i.e., reactivation plus new information). There was an increase in subsequent true memories for reactivated targets and for subsequent false memories for lures that followed reactivated targets, when compared to baseline target and lure photos. However, the influence of reactivation on subsequent memories was reduced in older adults. These data reveal that aging alters reactivation-related updating processes that allow memories to be strengthened and updated with new information-consequently reducing memory distortions in older compared to young adults. PMID:24993055

Modifying memory for a museum tour in older adults: Reactivation-related updating that enhances and distorts memory is reduced in ageing.

PubMed

St Jacques, Peggy L; Montgomery, Daniel; Schacter, Daniel L

2015-01-01

Memory reactivation, the activation of a latent memory trace when we are reminded of a past experience, strengthens memory but can also contribute to distortions if new information present during reactivation is integrated with existing memory. In a previous study in young adults we found that the quality of memory reactivation, manipulated using the principle of encoding specificity and indexed by recollection ratings, modulated subsequent true and false memories for events experienced during a museum tour. Here in this study, we examined age-related changes in the quality of memory reactivation on subsequent memory. Memories of museum stops in young and older adults were reactivated and then immediately followed by the presentation of a novel lure photo from an alternate tour version (i.e., reactivation plus new information). There was an increase in subsequent true memories for reactivated targets and for subsequent false memories for lures that followed reactivated targets, when compared to baseline target and lure photos. However, the influence of reactivation on subsequent memories was reduced in older adults. These data reveal that ageing alters reactivation-related updating processes that allow memories to be strengthened and updated with new information, consequently reducing memory distortions in older adults compared to young adults.

c-Rel, an NF-[kappa]B Family Transcription Factor, Is Required for Hippocampal Long-Term Synaptic Plasticity and Memory Formation

ERIC Educational Resources Information Center

Ahn, Hyung Jin; Hernandez, Caterina M.; Levenson, Jonathan M.; Lubin, Farah D.; Liou, Hsiou-Chi; Sweatt, J. David

2008-01-01

Transcription is a critical component for consolidation of long-term memory. However, relatively few transcriptional mechanisms have been identified for the regulation of gene expression in memory formation. In the current study, we investigated the activity of one specific member of the NF-[kappa]B transcription factor family, c-Rel, during…

Involvement of the Anterior Cingulate Cortex in Formation, Consolidation, and Reconsolidation of Recent and Remote Contextual Fear Memory

ERIC Educational Resources Information Center

Einarsson, Einar O.; Nader, Karim

2012-01-01

It has been suggested that memories become more stable and less susceptible to the disruption of reconsolidation over weeks after learning. Here, we test this by targeting the anterior cingulate cortex (ACC) and test its involvement in the formation, consolidation, and reconsolidation of recent and remote contextual fear memory. We found that…

Hemispheric asymmetries in discourse processing: evidence from false memories for lists and texts.

PubMed

Ben-Artzi, Elisheva; Faust, Miriam; Moeller, Edna

2009-01-01

Previous research suggests that the right hemisphere (RH) may contribute uniquely to discourse and text processing by activating and maintaining a wide range of meanings, including more distantly related meanings. The present study used the word-lists false memory paradigm [Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 803-814.] to examine the hypothesis that difference between the two cerebral hemispheres in discourse processing may be due, at least partly, to memory representations for implicit text-related semantic information. Specifically, we tested the susceptibility of the left hemisphere (LH) and RH to unpresented target words following the presentation of semantically related words appearing in either word lists or short texts. Findings showed that the RH produced more false alarms than the LH for unpresented target words following either word lists or texts. These findings reveal hemispheric differences in memory for semantically related information and suggest that RH advantage in long-term maintenance of a wide range of text-related word meanings may be one aspect of its unique contribution to the construction of a discourse model. The results support the RH coarse semantic coding theory [Beeman, M. (1998). Coarse semantic coding and discourse comprehension. In M. Beeman & C. Chiarello (Eds.), Right hemisphere language comprehension: Perspectives from cognitive neuroscience (pp. 255-284). Mahwah, NJ: Erlbaum.] and suggest that hemispheric differences in semantic processing during language comprehension extend also to verbal memory.

Molecular mechanisms underlying formation of long-term reward memories and extinction memories in the honeybee (Apis mellifera)

PubMed Central

2014-01-01

The honeybee (Apis mellifera) has long served as an invertebrate model organism for reward learning and memory research. Its capacity for learning and memory formation is rooted in the ecological need to efficiently collect nectar and pollen during summer to ensure survival of the hive during winter. Foraging bees learn to associate a flower's characteristic features with a reward in a way that resembles olfactory appetitive classical conditioning, a learning paradigm that is used to study mechanisms underlying learning and memory formation in the honeybee. Due to a plethora of studies on appetitive classical conditioning and phenomena related to it, the honeybee is one of the best characterized invertebrate model organisms from a learning psychological point of view. Moreover, classical conditioning and associated behavioral phenomena are surprisingly similar in honeybees and vertebrates, suggesting a convergence of underlying neuronal processes, including the molecular mechanisms that contribute to them. Here I review current thinking on the molecular mechanisms underlying long-term memory (LTM) formation in honeybees following classical conditioning and extinction, demonstrating that an in-depth analysis of the molecular mechanisms of classical conditioning in honeybees might add to our understanding of associative learning in honeybees and vertebrates. PMID:25225299

Using Implicit Instructional Cues to Influence False Memory Induction.

PubMed

Cirelli, Laura K; Dickinson, Joël; Poirier, Marie

2015-10-01

Previous research has shown that explicit cues specific to the encoding process (endogenous) or characteristic of the stimuli themselves (exogenous) can be used to direct a reader's attentional resources towards either relational or item-specific information. By directing attention to relational information (and therefore away from item-specific information) the rate of false memory induction can be increased. The purpose of the current study was to investigate if a similar effect would be found by manipulating implicitly endogenous cues. An instructional manipulation was used to influence the perceptual action participants performed on word stimuli during the encoding of DRM list words. Results demonstrated that the instructional conditions that encouraged faster processing also led to an increased rate of false memory induction for semantically related words, supporting the hypothesis that attention was directed towards relational information. This finding supports the impoverished relational processing account of false memory induction. This supports the idea that implicitly endogenous cues, exogenous cues (like font) or explicitly endogenous cues (like training) can direct attentional resources during encoding.

Memory for radio advertisements: the effect of program and typicality.

PubMed

Martín-Luengo, Beatriz; Luna, Karlos; Migueles, Malen

2013-01-01

We examined the influence of the type of radio program on the memory for radio advertisements. We also investigated the role in memory of the typicality (high or low) of the elements of the products advertised. Participants listened to three types of programs (interesting, boring, enjoyable) with two advertisements embedded in each. After completing a filler task, the participants performed a true/false recognition test. Hits and false alarm rates were higher for the interesting and enjoyable programs than for the boring one. There were also more hits and false alarms for the high-typicality elements. The response criterion for the advertisements embedded in the boring program was stricter than for the advertisements in other types of programs. We conclude that the type of program in which an advertisement is inserted and the nature of the elements of the advertisement affect both the number of hits and false alarms and the response criterion, but not the accuracy of the memory.

Subjective memory complaints are associated with brain activation supporting successful memory encoding.

PubMed

Hayes, Jessica M; Tang, Lingfei; Viviano, Raymond P; van Rooden, Sanneke; Ofen, Noa; Damoiseaux, Jessica S

2017-12-01

Subjective memory complaints, the perceived decline in cognitive abilities in the absence of clinical deficits, may precede Alzheimer's disease. Individuals with subjective memory complaints show differential brain activation during memory encoding; however, whether such differences contribute to successful memory formation remains unclear. Here, we investigated how subsequent memory effects, activation which is greater for hits than misses during an encoding task, differed between healthy older adults aged 50 to 85 years with (n = 23) and without (n = 41) memory complaints. Older adults with memory complaints, compared to those without, showed lower subsequent memory effects in the occipital lobe, superior parietal lobe, and posterior cingulate cortex. In addition, older adults with more memory complaints showed a more negative subsequent memory effects in areas of the default mode network, including the posterior cingulate cortex, precuneus, and ventromedial prefrontal cortex. Our findings suggest that for successful memory formation, older adults with subjective memory complaints rely on distinct neural mechanisms which may reflect an overall decreased task-directed attention. Copyright © 2017 Elsevier Inc. All rights reserved.

Roles of α- and β-estrogen receptors in mouse social recognition memory: effects of gender and the estrous cycle.

PubMed

Sánchez-Andrade, G; Kendrick, K M

2011-01-01

Establishing clear effects of gender and natural hormonal changes during female ovarian cycles on cognitive function has often proved difficult. Here we have investigated such effects on the formation and long-term (24 h) maintenance of social recognition memory in mice together with the respective involvement of α- and β-estrogen receptors using α- and β-estrogen receptor knockout mice and wildtype controls. Results in wildtype animals showed that while females successfully formed a memory in the context of a habituation/dishabituation paradigm at all stages of their ovarian cycle, only when learning occurred during proestrus (when estrogen levels are highest) was it retained after 24 h. In α-receptor knockout mice (which showed no ovarian cycles) both formation and maintenance of this social recognition memory were impaired, whereas β-receptor knockouts showed no significant deficits and exhibited the same proestrus-dependent retention of memory at 24 h. To investigate possible sex differences, male α- and β-estrogen receptor knockout mice were also tested and showed similar effects to females excepting that α-receptor knockouts had normal memory formation and only exhibited a 24 h retention deficit. This indicates a greater dependence in females on α-receptor expression for memory formation in this task. Since non-specific motivational and attentional aspects of the task were unaffected, our findings suggest a general α-receptor dependent facilitation of memory formation by estrogen as well as an enhanced long-term retention during proestrus. Results are discussed in terms of the differential roles of the two estrogen receptors, the neural substrates involved and putative interactions with oxytocin. Copyright © 2010 Elsevier Inc. All rights reserved.

Memory disorders in probable Alzheimer's disease: the role of hippocampal atrophy as shown with MRI.

PubMed Central

Deweer, B; Lehéricy, S; Pillon, B; Baulac, M; Chiras, J; Marsault, C; Agid, Y; Dubois, B

1995-01-01

Magnetic resonance based volumetric measures of hippocampal formation, amygdala (A), caudate nucleus (CN), normalised for total intracranial volume (TIV), were analysed in relation to measures of cognitive deterioration and specific features of memory functions in 18 patients with probable Alzheimer's disease. Neuropsychological examination included the mini mental state examination (MMSE), the Mattis dementia rating scale (DRS), tests of executive functions, assessment of language abilities and praxis, the Wechsler memory scale (WMS), the California verbal learning test (CVLT) and the Grober and Buschke test. The volume of the hippocampal formation (HF/TIV) was correlated with specific memory variables: memory quotient and paired associates of the WMS; intrusions and discriminability at recognition for the Grober and Buschke test. By contrast, except for intrusions, no correlations were found between memory variables and the volume of amygdala (A/TIV). No correlations were found between the volume of caudate nuclei (CN/TIV) and any neuropsychological score. The volume of the hippocampal formation was therefore selectively related to quantitative and qualitative aspects of memory performance in patients with probable Alzheimer's disease. Images PMID:7745409

Social Memory Formation Rapidly and Differentially Affects the Motivation and Performance of Vocal Communication Signals in the Bengalese Finch (Lonchura striata var. domestica).

PubMed

Toccalino, Danielle C; Sun, Herie; Sakata, Jon T

2016-01-01

Cognitive processes like the formation of social memories can shape the nature of social interactions between conspecifics. Male songbirds use vocal signals during courtship interactions with females, but the degree to which social memory and familiarity influences the likelihood and structure of male courtship song remains largely unknown. Using a habituation-dishabituation paradigm, we found that a single, brief (<30 s) exposure to a female led to the formation of a short-term memory for that female: adult male Bengalese finches were significantly less likely to produce courtship song to an individual female when re-exposed to her 5 min later (i.e., habituation). Familiarity also rapidly decreased the duration of courtship songs but did not affect other measures of song performance (e.g., song tempo and the stereotypy of syllable structure and sequencing). Consistent with a contribution of social memory to the decrease in courtship song with repeated exposures to the same female, the likelihood that male Bengalese finches produced courtship song increased when they were exposed to a different female (i.e., dishabituation). Three consecutive exposures to individual females also led to the formation of a longer-term memory that persisted over days. Specifically, when courtship song production was assessed 2 days after initial exposures to females, males produced fewer and shorter courtship songs to familiar females than to unfamiliar females. Measures of song performance, however, were not different between courtship songs produced to familiar and unfamiliar females. The formation of a longer-term memory for individual females seemed to require at least three exposures because males did not differentially produce courtship song to unfamiliar females and females that they had been exposed to only once or twice. Taken together, these data indicate that brief exposures to individual females led to the rapid formation and persistence of social memories and support the existence of distinct mechanisms underlying the motivation to produce and the performance of courtship song.

Circadian modulation of short-term memory in Drosophila.

PubMed

Lyons, Lisa C; Roman, Gregg

2009-01-01

Endogenous biological clocks are widespread regulators of behavior and physiology, allowing for a more efficient allocation of efforts and resources over the course of a day. The extent that different processes are regulated by circadian oscillators, however, is not fully understood. We investigated the role of the circadian clock on short-term associative memory formation using a negatively reinforced olfactory-learning paradigm in Drosophila melanogaster. We found that memory formation was regulated in a circadian manner. The peak performance in short-term memory (STM) occurred during the early subjective night with a twofold performance amplitude after a single pairing of conditioned and unconditioned stimuli. This rhythm in memory is eliminated in both timeless and period mutants and is absent during constant light conditions. Circadian gating of sensory perception does not appear to underlie the rhythm in short-term memory as evidenced by the nonrhythmic shock avoidance and olfactory avoidance behaviors. Moreover, central brain oscillators appear to be responsible for the modulation as cryptochrome mutants, in which the antennal circadian oscillators are nonfunctional, demonstrate robust circadian rhythms in short-term memory. Together these data suggest that central, rather than peripheral, circadian oscillators modulate the formation of short-term associative memory and not the perception of the stimuli.

Memory vs memory-like: The different facets of CD8+ T-cell memory in HCV infection.

PubMed

Hofmann, Maike; Wieland, Dominik; Pircher, Hanspeter; Thimme, Robert

2018-05-01

Memory CD8 + T cells are essential in orchestrating protection from re-infection. Hallmarks of virus-specific memory CD8 + T cells are the capacity to mount recall responses with rapid induction of effector cell function and antigen-independent survival. Growing evidence reveals that even chronic infection does not preclude virus-specific CD8 + T-cell memory formation. However, whether this kind of CD8 + T-cell memory that is established during chronic infection is indeed functional and provides protection from re-infection is still unclear. Human chronic hepatitis C virus infection represents a unique model system to study virus-specific CD8 + T-cell memory formation during and after cessation of persisting antigen stimulation. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Neuropeptide S enhances memory and mitigates memory impairment induced by MK801, scopolamine or Aβ₁₋₄₂ in mice novel object and object location recognition tasks.

PubMed

Han, Ren-Wen; Zhang, Rui-San; Xu, Hong-Jiao; Chang, Min; Peng, Ya-Li; Wang, Rui

2013-07-01

Neuropeptide S (NPS), the endogenous ligand of NPSR, has been shown to promote arousal and anxiolytic-like effects. According to the predominant distribution of NPSR in brain tissues associated with learning and memory, NPS has been reported to modulate cognitive function in rodents. Here, we investigated the role of NPS in memory formation, and determined whether NPS could mitigate memory impairment induced by selective N-methyl-D-aspartate receptor antagonist MK801, muscarinic cholinergic receptor antagonist scopolamine or Aβ₁₋₄₂ in mice, using novel object and object location recognition tasks. Intracerebroventricular (i.c.v.) injection of 1 nmol NPS 5 min after training not only facilitated object recognition memory formation, but also prolonged memory retention in both tasks. The improvement of object recognition memory induced by NPS could be blocked by the selective NPSR antagonist SHA 68, indicating pharmacological specificity. Then, we found that i.c.v. injection of NPS reversed memory disruption induced by MK801, scopolamine or Aβ₁₋₄₂ in both tasks. In summary, our results indicate that NPS facilitates memory formation and prolongs the retention of memory through activation of the NPSR, and mitigates amnesia induced by blockage of glutamatergic or cholinergic system or by Aβ₁₋₄₂, suggesting that NPS/NPSR system may be a new target for enhancing memory and treating amnesia. Copyright © 2013 Elsevier Ltd. All rights reserved.

Retrieval Failure Contributes to Gist-Based False Recognition

PubMed Central

Guerin, Scott A.; Robbins, Clifford A.; Gilmore, Adrian W.; Schacter, Daniel L.

2011-01-01

People often falsely recognize items that are similar to previously encountered items. This robust memory error is referred to as gist-based false recognition. A widely held view is that this error occurs because the details fade rapidly from our memory. Contrary to this view, an initial experiment revealed that, following the same encoding conditions that produce high rates of gist-based false recognition, participants overwhelmingly chose the correct target rather than its related foil when given the option to do so. A second experiment showed that this result is due to increased access to stored details provided by reinstatement of the originally encoded photograph, rather than to increased attention to the details. Collectively, these results suggest that details needed for accurate recognition are, to a large extent, still stored in memory and that a critical factor determining whether false recognition will occur is whether these details can be accessed during retrieval. PMID:22125357

The neural correlates of gist-based true and false recognition

PubMed Central

Gutchess, Angela H.; Schacter, Daniel L.

2012-01-01

When information is thematically related to previously studied information, gist-based processes contribute to false recognition. Using functional MRI, we examined the neural correlates of gist-based recognition as a function of increasing numbers of studied exemplars. Sixteen participants incidentally encoded small, medium, and large sets of pictures, and we compared the neural response at recognition using parametric modulation analyses. For hits, regions in middle occipital, middle temporal, and posterior parietal cortex linearly modulated their activity according to the number of related encoded items. For false alarms, visual, parietal, and hippocampal regions were modulated as a function of the encoded set size. The present results are consistent with prior work in that the neural regions supporting veridical memory also contribute to false memory for related information. The results also reveal that these regions respond to the degree of relatedness among similar items, and implicate perceptual and constructive processes in gist-based false memory. PMID:22155331

Mood and the DRM paradigm: An investigation of the effects of valence and arousal on false memory.

PubMed

Van Damme, Ilse

2013-06-01

Recent studies regarding the effect of mood on the DRM (Deese-Roediger-McDermott) illusion have not been able to clearly establish yet whether valence or arousal is most critical in determining susceptibility to false memories, nor what the underlying processes are. In three experiments, both the valence and the level of arousal of participants' mood were manipulated. Six conditions were used: positive mood with high/low arousal, negative mood with high/low arousal, neutral mood, and a control condition. Memory was tested by means of immediate and delayed recognition and immediate free recall. The mood induction procedure was effective. For recognition memory, there was an effect of arousal on the endorsement of critical lures. Low-arousal moods elicited more false recognition than high-arousal moods, regardless of valence. Based on signal detection analyses, the effect was attributed to more liberal response criteria with low arousal, in combination with a tendency towards improved item-specific memory with high arousal.

Effects of cortisol suppression on sleep-associated consolidation of neutral and emotional memory.

PubMed

Wagner, Ullrich; Degirmenci, Metin; Drosopoulos, Spyridon; Perras, Boris; Born, Jan

2005-12-01

Previous research indicates that hippocampus-dependent declarative memory benefits from early nocturnal sleep, when slow-wave sleep (SWS) prevails and cortisol release is minimal, whereas amygdala-dependent emotional memory is enhanced through late sleep, when rapid eye movement (REM) sleep predominates. The role of the strong cortisol rise accompanying late sleep for emotional memory consolidation has not yet been investigated. Effects of the cortisol synthesis inhibitor metyrapone on sleep-associated consolidation of memory for neutral and emotional texts were investigated in a randomized, double-blind, placebo-controlled study in 14 healthy men. Learning took place immediately before treatment, which was followed by 8 hours of sleep. Retrieval was tested at 11 am the next morning. Metyrapone suppressed cortisol during sleep and blocked particularly the late-night rise in cortisol. It reduced SWS and concomitantly impaired the consolidation of neutral texts. Emotional texts were spared from this impairing influence, however. Metyrapone even amplified emotional enhancement in text recall indicating amygdala-dependent memory. Cortisol blockade during sleep impairs hippocampus-dependent declarative memory formation but enhances amygdala-dependent emotional memory formation. The natural cortisol rise during late sleep may thus protect from overshooting emotional memory formation, a mechanism possibly pertinent to the development of posttraumatic stress disorder.

Pharmacologic inhibition of phospholipase C in the brain attenuates early memory formation in the honeybee (Apis mellifera L.)

PubMed Central

Iino, Shiori; Kubo, Takeo

2018-01-01

ABSTRACT Although the molecular mechanisms involved in learning and memory in insects have been studied intensively, the intracellular signaling mechanisms involved in early memory formation are not fully understood. We previously demonstrated that phospholipase C epsilon (PLCe), whose product is involved in calcium signaling, is almost selectively expressed in the mushroom bodies, a brain structure important for learning and memory in the honeybee. Here, we pharmacologically examined the role of phospholipase C (PLC) in learning and memory in the honeybee. First, we identified four genes for PLC subtypes in the honeybee genome database. Quantitative reverse transcription-polymerase chain reaction revealed that, among these four genes, three, including PLCe, were expressed higher in the brain than in sensory organs in worker honeybees, suggesting their main roles in the brain. Edelfosine and neomycin, pan-PLC inhibitors, significantly decreased PLC activities in homogenates of the brain tissues. These drugs injected into the head of foragers significantly attenuated memory acquisition in comparison with the control groups, whereas memory retention was not affected. These findings suggest that PLC in the brain is involved in early memory formation in the honeybee. To our knowledge, this is the first report of a role for PLC in learning and memory in an insect. PMID:29330349

Level of processing modulates the neural correlates of emotional memory formation

PubMed Central

Ritchey, Maureen; LaBar, Kevin S.; Cabeza, Roberto

2010-01-01

Emotion is known to influence multiple aspects of memory formation, including the initial encoding of the memory trace and its consolidation over time. However, the neural mechanisms whereby emotion impacts memory encoding remain largely unexplored. The present study employed a levels-of-processing manipulation to characterize the impact of emotion on encoding with and without the influence of elaborative processes. Participants viewed emotionally negative, neutral, and positive scenes under two conditions: a shallow condition focused on the perceptual features of the scenes and a deep condition that queried their semantic meaning. Recognition memory was tested 2 days later. Results showed that emotional memory enhancements were greatest in the shallow condition. FMRI analyses revealed that the right amygdala predicted subsequent emotional memory in the shallow more than deep condition, whereas the right ventrolateral prefrontal cortex demonstrated the reverse pattern. Furthermore, the association of these regions with the hippocampus was modulated by valence: the amygdala-hippocampal link was strongest for negative stimuli, whereas the prefrontal-hippocampal link was strongest for positive stimuli. Taken together, these results suggest two distinct activation patterns underlying emotional memory formation: an amygdala component that promotes memory during shallow encoding, especially for negative information, and a prefrontal component that provides extra benefits during deep encoding, especially for positive information. PMID:20350176

Level of processing modulates the neural correlates of emotional memory formation.

PubMed

Ritchey, Maureen; LaBar, Kevin S; Cabeza, Roberto

2011-04-01

Emotion is known to influence multiple aspects of memory formation, including the initial encoding of the memory trace and its consolidation over time. However, the neural mechanisms whereby emotion impacts memory encoding remain largely unexplored. The present study used a levels-of-processing manipulation to characterize the impact of emotion on encoding with and without the influence of elaborative processes. Participants viewed emotionally negative, neutral, and positive scenes under two conditions: a shallow condition focused on the perceptual features of the scenes and a deep condition that queried their semantic meaning. Recognition memory was tested 2 days later. Results showed that emotional memory enhancements were greatest in the shallow condition. fMRI analyses revealed that the right amygdala predicted subsequent emotional memory in the shallow more than deep condition, whereas the right ventrolateral PFC demonstrated the reverse pattern. Furthermore, the association of these regions with the hippocampus was modulated by valence: the amygdala-hippocampal link was strongest for negative stimuli, whereas the prefrontal-hippocampal link was strongest for positive stimuli. Taken together, these results suggest two distinct activation patterns underlying emotional memory formation: an amygdala component that promotes memory during shallow encoding, especially for negative information, and a prefrontal component that provides extra benefits during deep encoding, especially for positive information.

Stress and glucocorticoid receptor-dependent mechanisms in long-term memory: from adaptive responses to psychopathologies

PubMed Central

Finsterwald, Charles; Alberini, Cristina M.

2013-01-01

A proper response against stressors is critical for survival. In mammals, the stress response is primarily mediated by secretion of glucocorticoids via the hypothalamic-pituitaryadrenocortical (HPA) axis and release of catecholamines through adrenergic neurotransmission. Activation of these pathways results in a quick physical response to the stress and, in adaptive conditions, mediates long-term changes in the brain that lead to the formation of long-term memories of the experience. These long-term memories are an essential adaptive mechanism that allows an animal to effectively face similar demands again. Indeed, a moderate stress level has a strong positive effect on memory and cognition, as a single arousing or moderately stressful event can be remembered for up to a lifetime. Conversely, exposure to extreme, traumatic, or chronic stress can have the opposite effect and cause memory loss, cognitive impairments, and stress-related psychopathologies such as anxiety disorders, depression and post-traumatic stress disorder (PTSD). While more effort has been devoted to the understanding of the effects of the negative effects of chronic stress, much less has been done thus far on the identification of the mechanisms engaged in the brain when stress promotes long-term memory formation. Understanding these mechanisms will provide critical information for use in ameliorating memory processes in both normal and pathological conditions. Here, we will review the role of glucocorticoids and glucocorticoid receptors (GRs) in memory formation and modulation. Furthermore, we will discuss recent findings on the molecular cascade of events underlying the effect of GR activation in adaptive levels of stress that leads to strong, long-lasting memories. Our recent data indicate that the positive effects of GR activation on memory consolidation critically engage the brain-derived neurotrophic factor (BDNF) pathway. We propose and will discuss the hypothesis that stress promotes the formation of strong long-term memories because the activation of hippocampal GRs after learning is coupled to the recruitment of the growth and pro-survival BDNF/cAMP response element-binding protein (CREB) pathway, which is well-know to be a general mechanism required for long-term memory formation. We will then speculate about how these results may explain the negative effects of traumatic or chronic stress on memory and cognitive functions. PMID:24113652

Rapid, experience-dependent translation of neurogranin enables memory encoding.

PubMed

Jones, Kendrick J; Templet, Sebastian; Zemoura, Khaled; Kuzniewska, Bozena; Pena, Franciso X; Hwang, Hongik; Lei, Ding J; Haensgen, Henny; Nguyen, Shannon; Saenz, Christopher; Lewis, Michael; Dziembowska, Magdalena; Xu, Weifeng

2018-06-19

Experience induces de novo protein synthesis in the brain and protein synthesis is required for long-term memory. It is important to define the critical temporal window of protein synthesis and identify newly synthesized proteins required for memory formation. Using a behavioral paradigm that temporally separates the contextual exposure from the association with fear, we found that protein synthesis during the transient window of context exposure is required for contextual memory formation. Among an array of putative activity-dependent translational neuronal targets tested, we identified one candidate, a schizophrenia-associated candidate mRNA, neurogranin (Ng, encoded by the Nrgn gene) responding to novel-context exposure. The Ng mRNA was recruited to the actively translating mRNA pool upon novel-context exposure, and its protein levels were rapidly increased in the hippocampus. By specifically blocking activity-dependent translation of Ng using virus-mediated molecular perturbation, we show that experience-dependent translation of Ng in the hippocampus is required for contextual memory formation. We further interrogated the molecular mechanism underlying the experience-dependent translation of Ng, and found that fragile-X mental retardation protein (FMRP) interacts with the 3'UTR of the Nrgn mRNA and is required for activity-dependent translation of Ng in the synaptic compartment and contextual memory formation. Our results reveal that FMRP-mediated, experience-dependent, rapid enhancement of Ng translation in the hippocampus during the memory acquisition enables durable context memory encoding. Copyright © 2018 the Author(s). Published by PNAS.

Rapid, experience-dependent translation of neurogranin enables memory encoding

PubMed Central

Jones, Kendrick J.; Templet, Sebastian; Zemoura, Khaled; Pena, Franciso X.; Hwang, Hongik; Lei, Ding J.; Haensgen, Henny; Nguyen, Shannon; Saenz, Christopher; Lewis, Michael; Dziembowska, Magdalena

2018-01-01

Experience induces de novo protein synthesis in the brain and protein synthesis is required for long-term memory. It is important to define the critical temporal window of protein synthesis and identify newly synthesized proteins required for memory formation. Using a behavioral paradigm that temporally separates the contextual exposure from the association with fear, we found that protein synthesis during the transient window of context exposure is required for contextual memory formation. Among an array of putative activity-dependent translational neuronal targets tested, we identified one candidate, a schizophrenia-associated candidate mRNA, neurogranin (Ng, encoded by the Nrgn gene) responding to novel-context exposure. The Ng mRNA was recruited to the actively translating mRNA pool upon novel-context exposure, and its protein levels were rapidly increased in the hippocampus. By specifically blocking activity-dependent translation of Ng using virus-mediated molecular perturbation, we show that experience-dependent translation of Ng in the hippocampus is required for contextual memory formation. We further interrogated the molecular mechanism underlying the experience-dependent translation of Ng, and found that fragile-X mental retardation protein (FMRP) interacts with the 3′UTR of the Nrgn mRNA and is required for activity-dependent translation of Ng in the synaptic compartment and contextual memory formation. Our results reveal that FMRP-mediated, experience-dependent, rapid enhancement of Ng translation in the hippocampus during the memory acquisition enables durable context memory encoding. PMID:29880715

Knowledge of Normal versus Pathological Memory Aging among Police Officers

ERIC Educational Resources Information Center

Hawley, Karri S.; Garrity, April W.; Cherry, Katie E.

2005-01-01

The authors examined police officers' knowledge of memory changes in adulthood utilizing the Knowledge of Memory Aging Questionnaire (KMAQ). The KMAQ is a 28-item true/false questionnaire that covers a broad range of topics related to normal memory aging due to maturational processes and pathological memory aging, such as adult dementia. Results…

On the persuadability of memory: Is changing people's memories no more than changing their minds?

PubMed

Nash, Robert A; Wheeler, Rebecca L; Hope, Lorraine

2015-05-01

The observation of parallels between the memory distortion and persuasion literatures leads, quite logically, to the appealing notion that people can be 'persuaded' to change their memories. Indeed, numerous studies show that memory can be influenced and distorted by a variety of persuasive tactics, and the theoretical accounts commonly used by researchers to explain episodic and autobiographical memory distortion phenomena can generally predict and explain these persuasion effects. Yet, despite these empirical and theoretical overlaps, explicit reference to persuasion and attitude-change research in the memory distortion literature is surprisingly rare. In this paper, we argue that stronger theoretical foundations are needed to draw the memory distortion and persuasion literatures together in a productive direction. We reason that theoretical approaches to remembering that distinguish (false) beliefs in the occurrence of events from (false) memories of those events - compatible with a source monitoring approach - would be beneficial to this end. Such approaches, we argue, would provide a stronger platform to use persuasion findings to enhance the psychological understanding of memory distortion. © 2014 The British Psychological Society.

Inhibition of histone deacetylase 3 via RGFP966 facilitates cortical plasticity underlying unusually accurate auditory associative cue memory for excitatory and inhibitory cue-reward associations.

PubMed

Shang, Andrea; Bylipudi, Sooraz; Bieszczad, Kasia M

2018-05-31

Epigenetic mechanisms are key for regulating long-term memory (LTM) and are known to exert control on memory formation in multiple systems of the adult brain, including the sensory cortex. One epigenetic mechanism is chromatin modification by histone acetylation. Blocking the action of histone de-acetylases (HDACs) that normally negatively regulate LTM by repressing transcription has been shown to enable memory formation. Indeed, HDAC inhibition appears to facilitate memory by altering the dynamics of gene expression events important for memory consolidation. However, less understood are the ways in which molecular-level consolidation processes alter subsequent memory to enhance storage or facilitate retrieval. Here we used a sensory perspective to investigate whether the characteristics of memory formed with HDAC inhibitors are different from naturally-formed memory. One possibility is that HDAC inhibition enables memory to form with greater sensory detail than normal. Because the auditory system undergoes learning-induced remodeling that provides substrates for sound-specific LTM, we aimed to identify behavioral effects of HDAC inhibition on memory for specific sound features using a standard model of auditory associative cue-reward learning, memory, and cortical plasticity. We found that three systemic post-training treatments of an HDAC3-inhibitor (RGPF966, Abcam Inc.) in rats in the early phase of training facilitated auditory discriminative learning, changed auditory cortical tuning, and increased the specificity for acoustic frequency formed in memory of both excitatory (S+) and inhibitory (S-) associations for at least 2 weeks. The findings support that epigenetic mechanisms act on neural and behavioral sensory acuity to increase the precision of associative cue memory, which can be revealed by studying the sensory characteristics of long-term associative memory formation with HDAC inhibitors. Published by Elsevier B.V.

Tracking the Fear Memory Engram: Discrete Populations of Neurons within Amygdala, Hypothalamus, and Lateral Septum Are Specifically Activated by Auditory Fear Conditioning

ERIC Educational Resources Information Center

Butler, Christopher W.; Wilson, Yvette M.; Gunnersen, Jenny M.; Murphy, Mark

2015-01-01

Memory formation is thought to occur via enhanced synaptic connectivity between populations of neurons in the brain. However, it has been difficult to localize and identify the neurons that are directly involved in the formation of any specific memory. We have previously used "fos-tau-lacZ" ("FTL") transgenic mice to identify…

The interaction of rhinal cortex and hippocampus in human declarative memory formation.

PubMed

Fell, Jürgen; Klaver, Peter; Elger, Christian E; Fernández, Guillén

2002-01-01

Human declarative memory formation crucially depends on processes within the medial temporal lobe (MTL). These processes can be monitored in real-time by recordings from depth electrodes implanted in the MTL of patients with epilepsy who undergo presurgical evaluation. In our studies, patients performed a word memorization task during depth EEG recording. Afterwards, the difference between event-related potentials (ERPs) corresponding to subsequently remembered versus forgotten words was analyzed. These kind of studies revealed that successful memory encoding is characterized by an early process generated by the rhinal cortex within 300 ms following stimulus onset. This rhinal process precedes a hippocampal process, which starts about 200 ms later. Further investigation revealed that the rhinal process seems to be a correlate of semantic preprocessing which supports memory formation, whereas the hippocampal process appears to be a correlate of an exclusively mnemonic operation. These studies yielded only indirect evidence for an interaction of rhinal cortex and hippocampus. Direct evidence for a memory related cooperation between both structures, however, has been found in a study analyzing so called gamma activity, EEG oscillations of around 40 Hz. This investigation showed that successful as opposed to unsuccessful memory formation is accompanied by an initial enhancement of rhinal-hippocampal phase synchronization, which is followed by a later desynchronization. Present knowledge about the function of phase synchronized gamma activity suggests that this phase coupling and decoupling initiates and later terminates communication between the two MTL structures. Phase synchronized rhinal-hippocampal gamma activity may, moreover, accomplish Hebbian synaptic modifications and thus provide an initial step of declarative memory formation on the synaptic level.

Context and Auditory Fear are Differentially Regulated by HDAC3 Activity in the Lateral and Basal Subnuclei of the Amygdala

PubMed Central

Kwapis, Janine L; Alaghband, Yasaman; López, Alberto J; White, André O; Campbell, Rianne R; Dang, Richard T; Rhee, Diane; Tran, Ashley V; Carl, Allison E; Matheos, Dina P; Wood, Marcelo A

2017-01-01

Histone acetylation is a fundamental epigenetic mechanism that is dynamically regulated during memory formation. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) compete to modulate histone acetylation, allowing for rapid changes in acetylation in response to a learning event. HDACs are known to be powerful negative regulators of memory formation, but it is not clear whether this function depends on HDAC enzymatic activity per se. Here, we tested whether the enzymatic activity of an individual Class I HDAC, HDAC3, has a role in fear memory formation in subregions of the hippocampus and amygdala. We found that fear conditioning drove expression of the immediate early genes cFos and Nr4a2 in the hippocampus, which coincided with reduced HDAC3 occupancy at these promoters. Using a dominant-negative, deacetylase-dead point mutant virus (AAV-HDAC3(Y298H)-v5), we found that selectively blocking HDAC3 deacetylase activity in either the dorsal hippocampus or basal nucleus of the amygdala enhanced context fear without affecting tone fear. Blocking HDAC3 activity in the lateral nucleus of the amygdala, on the other hand, enhanced tone, but not context fear memory. These results show for the first time that the enzymatic activity of HDAC3 functions to negatively regulate fear memory formation. Further, HDAC3 activity regulates different aspects of fear memory in the basal and lateral subregions of the amygdala. Thus, the deacetylase activity of HDAC3 is a powerful negative regulator of fear memory formation in multiple subregions of the fear circuit. PMID:27924874

Stably maintained dendritic spines are associated with lifelong memories

PubMed Central

Yang, Guang; Pan, Feng; Gan, Wen-Biao

2016-01-01

Changes in synaptic connections are considered essential for learning and memory formation1–6. However, it is unknown how neural circuits undergo continuous synaptic changes during learning while maintaining lifelong memories. Here we show, by following postsynaptic dendritic spines over time in the mouse cortex7–8, that learning and novel sensory experience lead to spine formation and elimination by a protracted process. The extent of spine remodelling correlates with behavioural improvement after learning, suggesting a crucial role of synaptic structural plasticity in memory formation and storage. Importantly, a small fraction of new spines induced by novel experience, together with most spines formed early during development and surviving experience-dependent elimination, are preserved throughout the entire life of an animal. These studies indicate that learning and daily sensory experience leave minute but permanent marks on cortical connections and suggest that lifelong memories are stored in largely stably connected synaptic networks. PMID:19946265

Chronic transcranial focal stimulation from tripolar concentric ring electrodes does not disrupt memory formation in rats.

PubMed

Luby, Matthew D; Makeyev, Oleksandr; Besio, Walter G

2014-01-01

Non-invasive electrical brain stimulation has shown potential utility as a treatment for seizures in epilepsy patients. Transcranial focal stimulation (TFS) via tripolar concentric ring electrodes (TCREs) has been effective in reducing seizure severity in acute rodent models, but it has yet to be determined whether or not it will serve as a viable long-term treatment strategy. Prior experiments indicate that a single dose of TFS via TCRE does not impact short- or long-term memory formation. The present study investigated if five daily doses of TFS via a TCRE on the scalp affected the memory. The spontaneous object recognition (SOR) test was used to evaluate the memory. Sham and TFS-treated groups were evaluated and both showed comparable levels of preference for novel objects, indicating successful memory formation. More work on repeated dosage strategies is important for establishing the safety and efficacy of TFS as a putative treatment.

Astrocyte-neuron lactate transport is required for long-term memory formation.

PubMed

Suzuki, Akinobu; Stern, Sarah A; Bozdagi, Ozlem; Huntley, George W; Walker, Ruth H; Magistretti, Pierre J; Alberini, Cristina M

2011-03-04

We report that, in the rat hippocampus, learning leads to a significant increase in extracellular lactate levels that derive from glycogen, an energy reserve selectively localized in astrocytes. Astrocytic glycogen breakdown and lactate release are essential for long-term but not short-term memory formation, and for the maintenance of long-term potentiation (LTP) of synaptic strength elicited in vivo. Disrupting the expression of the astrocytic lactate transporters monocarboxylate transporter 4 (MCT4) or MCT1 causes amnesia, which, like LTP impairment, is rescued by L-lactate but not equicaloric glucose. Disrupting the expression of the neuronal lactate transporter MCT2 also leads to amnesia that is unaffected by either L-lactate or glucose, suggesting that lactate import into neurons is necessary for long-term memory. Glycogenolysis and astrocytic lactate transporters are also critical for the induction of molecular changes required for memory formation, including the induction of phospho-CREB, Arc, and phospho-cofilin. We conclude that astrocyte-neuron lactate transport is required for long-term memory formation. Copyright © 2011 Elsevier Inc. All rights reserved.

Npas4 Is a Critical Regulator of Learning-Induced Plasticity at Mossy Fiber-CA3 Synapses during Contextual Memory Formation.

PubMed

Weng, Feng-Ju; Garcia, Rodrigo I; Lutzu, Stefano; Alviña, Karina; Zhang, Yuxiang; Dushko, Margaret; Ku, Taeyun; Zemoura, Khaled; Rich, David; Garcia-Dominguez, Dario; Hung, Matthew; Yelhekar, Tushar D; Sørensen, Andreas Toft; Xu, Weifeng; Chung, Kwanghun; Castillo, Pablo E; Lin, Yingxi

2018-03-07

Synaptic connections between hippocampal mossy fibers (MFs) and CA3 pyramidal neurons are essential for contextual memory encoding, but the molecular mechanisms regulating MF-CA3 synapses during memory formation and the exact nature of this regulation are poorly understood. Here we report that the activity-dependent transcription factor Npas4 selectively regulates the structure and strength of MF-CA3 synapses by restricting the number of their functional synaptic contacts without affecting the other synaptic inputs onto CA3 pyramidal neurons. Using an activity-dependent reporter, we identified CA3 pyramidal cells that were activated by contextual learning and found that MF inputs on these cells were selectively strengthened. Deletion of Npas4 prevented both contextual memory formation and this learning-induced synaptic modification. We further show that Npas4 regulates MF-CA3 synapses by controlling the expression of the polo-like kinase Plk2. Thus, Npas4 is a critical regulator of experience-dependent, structural, and functional plasticity at MF-CA3 synapses during contextual memory formation. Copyright © 2018 Elsevier Inc. All rights reserved.

Emotional face expression modulates occipital-frontal effective connectivity during memory formation in a bottom-up fashion.

PubMed

Xiu, Daiming; Geiger, Maximilian J; Klaver, Peter

2015-01-01

This study investigated the role of bottom-up and top-down neural mechanisms in the processing of emotional face expression during memory formation. Functional brain imaging data was acquired during incidental learning of positive ("happy"), neutral and negative ("angry" or "fearful") faces. Dynamic Causal Modeling (DCM) was applied on the functional magnetic resonance imaging (fMRI) data to characterize effective connectivity within a brain network involving face perception (inferior occipital gyrus and fusiform gyrus) and successful memory formation related areas (hippocampus, superior parietal lobule, amygdala, and orbitofrontal cortex). The bottom-up models assumed processing of emotional face expression along feed forward pathways to the orbitofrontal cortex. The top-down models assumed that the orbitofrontal cortex processed emotional valence and mediated connections to the hippocampus. A subsequent recognition memory test showed an effect of negative emotion on the response bias, but not on memory performance. Our DCM findings showed that the bottom-up model family of effective connectivity best explained the data across all subjects and specified that emotion affected most bottom-up connections to the orbitofrontal cortex, especially from the occipital visual cortex and superior parietal lobule. Of those pathways to the orbitofrontal cortex the connection from the inferior occipital gyrus correlated with memory performance independently of valence. We suggest that bottom-up neural mechanisms support effects of emotional face expression and memory formation in a parallel and partially overlapping fashion.

Role of Immediate-Early Genes in Synaptic Plasticity and Neuronal Ensembles Underlying the Memory Trace

PubMed Central

Minatohara, Keiichiro; Akiyoshi, Mika; Okuno, Hiroyuki

2016-01-01

In the brain, neuronal gene expression is dynamically changed in response to neuronal activity. In particular, the expression of immediate-early genes (IEGs) such as egr-1, c-fos, and Arc is rapidly and selectively upregulated in subsets of neurons in specific brain regions associated with learning and memory formation. IEG expression has therefore been widely used as a molecular marker for neuronal populations that undergo plastic changes underlying formation of long-term memory. In recent years, optogenetic and pharmacogenetic studies of neurons expressing c-fos or Arc have revealed that, during learning, IEG-positive neurons encode and store information that is required for memory recall, suggesting that they may be involved in formation of the memory trace. However, despite accumulating evidence for the role of IEGs in synaptic plasticity, the molecular and cellular mechanisms associated with this process remain unclear. In this review, we first summarize recent literature concerning the role of IEG-expressing neuronal ensembles in organizing the memory trace. We then focus on the physiological significance of IEGs, especially Arc, in synaptic plasticity, and describe our hypotheses about the importance of Arc expression in various types of input-specific circuit reorganization. Finally, we offer perspectives on Arc function that would unveil the role of IEG-expressing neurons in the formation of memory traces in the hippocampus and other brain areas. PMID:26778955

Understanding Developmental Reversals in False Memory: Reply to Ghetti (2008) and Howe (2008)

ERIC Educational Resources Information Center

Brainerd, C. J.; Reyna, V. F.; Ceci, S. J.; Holliday, R. E.

2008-01-01

S. Ghetti (2008) and M. L. Howe (2008) presented probative ideas for future research that will deepen scientific understanding of developmental reversals on false memory and establish boundary conditions for these counterintuitive patterns. Ghetti extended the purview of current theoretical principles by formulating hypotheses about how…

Analyzing False Memories in Children with Associative Lists Specific for Their Age

ERIC Educational Resources Information Center

Carneiro, Paula; Albuquerque, Pedro; Fernandez, Angel; Esteves, Francisco

2007-01-01

Two experiments attempted to resolve previous contradictory findings concerning developmental trends in false memories within the Deese-Roediger-McDermott (DRM) paradigm by using an improved methodology--constructing age-appropriate associative lists. The research also extended the DRM paradigm to preschoolers. Experiment 1 (N = 320) included…

Network Model of Decreased Context Utilization in Autism Spectrum Disorder

ERIC Educational Resources Information Center

Beversdorf, David Q.; Narayanan, Ananth; Hillier, Ashleigh; Hughes, John D.

2007-01-01

Individuals with autism spectrum disorders (ASD) demonstrate impaired utilization of context, which allows for superior performance on the "false memory" task. We report the application of a simplified parallel distributed processing model of context utilization to the false memory task. For individuals without ASD, experiments support a model…

Development of the False-Memory Illusion

ERIC Educational Resources Information Center

Brainerd, C. J.; Forrest, T. J.; Karibian, D.; Reyna, V. F.

2006-01-01

The counterintuitive developmental trend in the Deese-Roediger-McDermott (DRM) illusion (that false-memory responses increase with age) was investigated in learning-disabled and nondisabled children from the 6- to 14-year-old age range. Fuzzy-trace theory predicts that because there are qualitative differences in how younger versus older children…

False Memories for Shape Activate the Lateral Occipital Complex

ERIC Educational Resources Information Center

Karanian, Jessica M.; Slotnick, Scott D.

2017-01-01

Previous functional magnetic resonance imaging evidence has shown that false memories arise from higher-level conscious processing regions rather than lower-level sensory processing regions. In the present study, we assessed whether the lateral occipital complex (LOC)--a lower-level conscious shape processing region--was associated with false…

False Memories for Suggestions: The Impact of Conceptual Elaboration

ERIC Educational Resources Information Center

Zaragoza, Maria S.; Mitchell, Karen J.; Payment, Kristie; Drivdahl, Sarah

2011-01-01

Relatively little attention has been paid to the potential role that reflecting on the meaning and implications of suggested events (i.e., conceptual elaboration) might play in promoting the creation of false memories. Two experiments assessed whether encouraging repeated conceptual elaboration, would, like perceptual elaboration, increase false…

New learning while consolidating memory during sleep is actively blocked by a protein synthesis dependent process

PubMed Central

Levy, Roi; Levitan, David; Susswein, Abraham J

2016-01-01

Brief experiences while a memory is consolidated may capture the consolidation, perhaps producing a maladaptive memory, or may interrupt the consolidation. Since consolidation occurs during sleep, even fleeting experiences when animals are awakened may produce maladaptive long-term memory, or may interrupt consolidation. In a learning paradigm affecting Aplysia feeding, when animals were trained after being awakened from sleep, interactions between new experiences and consolidation were prevented by blocking long-term memory arising from the new experiences. Inhibiting protein synthesis eliminated the block and allowed even a brief, generally ineffective training to produce long-term memory. Memory formation depended on consolidative proteins already expressed before training. After effective training, long term memory required subsequent transcription and translation. Memory formation during the sleep phase was correlated with increased CREB1 transcription, but not CREB2 transcription. Increased C/EBP transcription was a correlate of both effective and ineffective training and of treatments not producing memory. DOI: http://dx.doi.org/10.7554/eLife.17769.001 PMID:27919318

Statistical Computations Underlying the Dynamics of Memory Updating

PubMed Central

Gershman, Samuel J.; Radulescu, Angela; Norman, Kenneth A.; Niv, Yael

2014-01-01

Psychophysical and neurophysiological studies have suggested that memory is not simply a carbon copy of our experience: Memories are modified or new memories are formed depending on the dynamic structure of our experience, and specifically, on how gradually or abruptly the world changes. We present a statistical theory of memory formation in a dynamic environment, based on a nonparametric generalization of the switching Kalman filter. We show that this theory can qualitatively account for several psychophysical and neural phenomena, and present results of a new visual memory experiment aimed at testing the theory directly. Our experimental findings suggest that humans can use temporal discontinuities in the structure of the environment to determine when to form new memory traces. The statistical perspective we offer provides a coherent account of the conditions under which new experience is integrated into an old memory versus forming a new memory, and shows that memory formation depends on inferences about the underlying structure of our experience. PMID:25375816

New learning while consolidating memory during sleep is actively blocked by a protein synthesis dependent process.

PubMed

Levy, Roi; Levitan, David; Susswein, Abraham J

2016-12-06

Brief experiences while a memory is consolidated may capture the consolidation, perhaps producing a maladaptive memory, or may interrupt the consolidation. Since consolidation occurs during sleep, even fleeting experiences when animals are awakened may produce maladaptive long-term memory, or may interrupt consolidation. In a learning paradigm affecting Aplysia feeding, when animals were trained after being awakened from sleep, interactions between new experiences and consolidation were prevented by blocking long-term memory arising from the new experiences. Inhibiting protein synthesis eliminated the block and allowed even a brief, generally ineffective training to produce long-term memory. Memory formation depended on consolidative proteins already expressed before training. After effective training, long term memory required subsequent transcription and translation. Memory formation during the sleep phase was correlated with increased CREB1 transcription, but not CREB2 transcription. Increased C/EBP transcription was a correlate of both effective and ineffective training and of treatments not producing memory.

Working Memory, Long-Term Memory, and Medial Temporal Lobe Function

ERIC Educational Resources Information Center

Jeneson, Annette; Squire, Larry R.

2012-01-01

Early studies of memory-impaired patients with medial temporal lobe (MTL) damage led to the view that the hippocampus and related MTL structures are involved in the formation of long-term memory and that immediate memory and working memory are independent of these structures. This traditional idea has recently been revisited. Impaired performance…

[Early episodic memory impairments in Alzheimer's disease].

PubMed

Ergis, A-M; Eusop-Roussel, E

2008-05-01

Patients with Alzheimer's disease (AD) show early episodic memory impairments. Such deficits reflect specific impairments affecting one or several stages of encoding, storage and retrieval processes. However, AD patients not only have great difficulty retrieving memories and information but also suffer from distortions of memory, as intrusions and false recognitions. Intrusions can be defined as the unintentional recall of inappropriate information in a laboratory-learning tasks such as word-list recall and story recall. False recognition refers to the erroneous recognition of information that was not previously presented. The first objective of this review is to present studies from the literature that allowed a better understanding of the nature of episodic memory deficits in AD, and to examine recent research on false memories. The second part of this review is aimed at presenting recent research conducted on prospective memory (PM) in Alzheimer's disease. Prospective memory situations involve forming intentions and then realizing those intentions at some appropriate time in the future. Everyday examples of prospective memory include remembering to buy bread on the way home from work, remembering to give friends a message upon next encountering them, and remembering to take medication. Patients suffering from AD show difficulties in performing prospective tasks in daily life, according to the complaints of their care givers, and these difficulties are massively present at the first stages of the disease. Nevertheless, very few studies have been dedicated to this subject, although the evaluation of PM could be helpful for the early diagnosis of AD.

Attentional influences on memory formation: A tale of a not-so-simple story.

PubMed

Ortiz-Tudela, J; Milliken, B; Jiménez, L; Lupiáñez, J

2018-05-01

Is there a learning mechanism triggered by mere expectation violation? Is there some form of memory enhancement inherent to an event mismatching our predictions? Across seven experiments, we explore this issue by means of a validity paradigm. Although our manipulation clearly succeeded in generating an expectation and breaking it, the memory consequences of that expectation mismatch are not so obvious. We report here evidence of a null effect of expectation on memory formation. Our results (1) show that enhanced memory for unexpected events is not easily achieved and (2) call for a reevaluation of previous accounts of memory enhancements based on prediction error or difficulty of processing. Limitations of this study and possible implications for the field are discussed in detail.

Durable fear memories require PSD-95

PubMed Central

Fitzgerald, Paul J.; Pinard, Courtney R.; Camp, Marguerite C.; Feyder, Michael; Sah, Anupam; Bergstrom, Hadley; Graybeal, Carolyn; Liu, Yan; Schlüter, Oliver; Grant, Seth G.N.; Singewald, Nicolas; Xu, Weifeng; Holmes, Andrew

2014-01-01

Traumatic fear memories are highly durable but also dynamic, undergoing repeated reactivation and rehearsal over time. While overly persistent fear memories underlie anxiety disorders such as posttraumatic stress disorder, the key neural and molecular mechanisms underlying fear memory durability remain unclear. Post-synaptic density 95 (PSD-95) is a synaptic protein regulating glutamate receptor anchoring, synaptic stability and certain types of memory. Employing a loss-of-function mutant mouse lacking the guanylate kinase domain of PSD-95 (PSD-95GK), we analyzed the contribution of PSD-95 to fear memory formation and retrieval, and sought to identify the neural basis of PSD-95-mediated memory maintenance using ex vivo immediate-early gene mapping, in vivo neuronal recordings and viral-mediated knockdown approaches. We show that PSD-95 is dispensable for the formation and expression of recent fear memories, but essential for the formation of precise and flexible fear memories and for the maintenance of memories at remote time points. The failure of PSD-95GK mice to retrieve remote cued fear memories was associated with hypoactivation of the infralimbic cortex (IL) (not anterior cingulate (ACC) or prelimbic cortex), reduced IL single-unit firing and bursting, and attenuated IL gamma and theta oscillations. Adeno-associated PSD-95 virus-mediated knockdown in the IL, not ACC, was sufficient to impair recent fear extinction and remote fear memory, and remodel IL dendritic spines. Collectively, these data identify PSD-95 in the IL as a critical mechanism supporting the durability of fear memories over time. These preclinical findings have implications for developing novel approaches to treating trauma-based anxiety disorders that target the weakening of overly persistent fear memories. PMID:25510511

Durable fear memories require PSD-95.

PubMed

Fitzgerald, P J; Pinard, C R; Camp, M C; Feyder, M; Sah, A; Bergstrom, H C; Graybeal, C; Liu, Y; Schlüter, O M; Grant, S G; Singewald, N; Xu, W; Holmes, A

2015-07-01

Traumatic fear memories are highly durable but also dynamic, undergoing repeated reactivation and rehearsal over time. Although overly persistent fear memories underlie anxiety disorders, such as posttraumatic stress disorder, the key neural and molecular mechanisms underlying fear memory durability remain unclear. Postsynaptic density 95 (PSD-95) is a synaptic protein regulating glutamate receptor anchoring, synaptic stability and certain types of memory. Using a loss-of-function mutant mouse lacking the guanylate kinase domain of PSD-95 (PSD-95(GK)), we analyzed the contribution of PSD-95 to fear memory formation and retrieval, and sought to identify the neural basis of PSD-95-mediated memory maintenance using ex vivo immediate-early gene mapping, in vivo neuronal recordings and viral-mediated knockdown (KD) approaches. We show that PSD-95 is dispensable for the formation and expression of recent fear memories, but essential for the formation of precise and flexible fear memories and for the maintenance of memories at remote time points. The failure of PSD-95(GK) mice to retrieve remote cued fear memory was associated with hypoactivation of the infralimbic (IL) cortex (but not the anterior cingulate cortex (ACC) or prelimbic cortex), reduced IL single-unit firing and bursting, and attenuated IL gamma and theta oscillations. Adeno-associated virus-mediated PSD-95 KD in the IL, but not the ACC, was sufficient to impair recent fear extinction and remote fear memory, and remodel IL dendritic spines. Collectively, these data identify PSD-95 in the IL as a critical mechanism supporting the durability of fear memories over time. These preclinical findings have implications for developing novel approaches to treating trauma-based anxiety disorders that target the weakening of overly persistent fear memories.

IL-15 signaling promotes adoptive effector T-cell survival and memory formation in irradiation-induced lymphopenia.

PubMed

Xu, Aizhang; Bhanumathy, Kalpana Kalyanasundaram; Wu, Jie; Ye, Zhenmin; Freywald, Andrew; Leary, Scot C; Li, Rongxiu; Xiang, Jim

2016-01-01

Lymphopenia promotes naïve T-cell homeostatic proliferation and adoptive effector T-cell survival and memory formation. IL-7 plays a critical role in homeostatic proliferation, survival and memory formation of naïve T-cells in lymphopenia, and its underlying molecular mechanism has also been well studied. However, the mechanism for adoptively transferred effector T-cell survival and memory formation is not fully understood. Here, we transferred in vitro-activated transgenic OT-I CD8(+) effector T-cells into irradiation (600 rads)-induced lymphopenic C57BL/6, IL-7 knockout (KO) and IL-15 KO mice, and investigated the survival and memory formation of transferred T-cells in lymphopenia. We demonstrate that transferred T-cells prolong their survival and enhance their memory in lymphopenic mice, in a manner that depends on IL-15 signaling, but not IL-7. We determine that in vitro stimulation of naïve or effector T-cells with IL-7 and IL-15 reduces IL-7Rα, and increases and/or maintains IL-15Rβ expression, respectively. Consistent with these findings, the expression of IL-7Rα and IL-15Rβ is down- and up-regulated, respectively, in vivo on transferred T-cells in an early phase post T-cell transfer in lymphopenia. We further show that in vitro IL-15 restimulation-induced memory T-cells (compared to IL-2 restimulation-induced effector T-cells) and in vivo transferred T-cells in irradiated IL-15-sufficient C57BL/6 mice (compared to IL-15-deficient IL-15 KO mice) have increased mitochondrial content, but less NADH and lower mitochondrial potential (ΔΨm), and demonstrate greater phosphorylation of signal transducers and activators of transcription-5 (STAT5) and Unc-51-like kinase-1 (ULK1), and higher expression of B-cell leukemia/lymphoma-2 (Bcl2) and memory-, autophagy- and mitochondrial biogenesis-related molecules. Irradiation-induced lymphopenia promotes effector T-cell survival via IL-15 signaling the STAT5/Bcl2 pathway, enhances T-cell memory formation via IL-15 activation of the forkhead-box family of transcription factor (FOXO)/eomesodermin (Eomes) memory and ULK1/autophagy-related gene-7 (ATG7) autophagy pathways, and via IL-15 activation of the mitochondrial remodeling. Our data thus identify some important targets to consider when designing potent adoptive T-cell immunotherapies of cancer.

Habitat stability, predation risk and 'memory syndromes'.

PubMed

Dalesman, S; Rendle, A; Dall, S R X

2015-05-27

Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonstrates consistency among memory traits ('memory syndrome') related to threat avoidance and foraging. We used eight populations originating from three different habitat types: i) laboratory populations (stable habitat, predator-free); ii) river populations (fairly stable habitat, fish predation); and iii) ditch populations (unstable habitat, invertebrate predation). At a population level, there was a negative relationship between memories related to threat avoidance and food selectivity, but no consistency within habitat type. At an individual level, covariance between memory traits was dependent on habitat. Laboratory populations showed no covariance among memory traits, whereas river populations showed a positive correlation between food memories, and ditch populations demonstrated a negative relationship between threat memory and food memories. Therefore, selection pressures among habitats appear to act independently on memory trait covariation at an individual level and the average response within a population.

DNA Methylation Adjusts the Specificity of Memories Depending on the Learning Context and Promotes Relearning in Honeybees

PubMed Central

Biergans, Stephanie D.; Claudianos, Charles; Reinhard, Judith; Galizia, C. G.

2016-01-01

The activity of the epigenetic writers DNA methyltransferases (Dnmts) after olfactory reward conditioning is important for both stimulus-specific long-term memory (LTM) formation and extinction. It, however, remains unknown which components of memory formation Dnmts regulate (e.g., associative vs. non-associative) and in what context (e.g., varying training conditions). Here, we address these aspects in order to clarify the role of Dnmt-mediated DNA methylation in memory formation. We used a pharmacological Dnmt inhibitor and classical appetitive conditioning in the honeybee Apis mellifera, a well characterized model for classical conditioning. We quantified the effect of DNA methylation on naïve odor and sugar responses, and on responses following olfactory reward conditioning. We show that (1) Dnmts do not influence naïve odor or sugar responses, (2) Dnmts do not affect the learning of new stimuli, but (3) Dnmts influence odor-coding, i.e., ‘correct’ (stimulus-specific) LTM formation. Particularly, Dnmts reduce memory specificity when experience is low (one-trial training), and increase memory specificity when experience is high (multiple-trial training), generating an ecologically more useful response to learning. (4) In reversal learning conditions, Dnmts are involved in regulating both excitatory (re-acquisition) and inhibitory (forgetting) processes. PMID:27672359

DNA Methylation Adjusts the Specificity of Memories Depending on the Learning Context and Promotes Relearning in Honeybees.

PubMed

Biergans, Stephanie D; Claudianos, Charles; Reinhard, Judith; Galizia, C G

2016-01-01

The activity of the epigenetic writers DNA methyltransferases (Dnmts) after olfactory reward conditioning is important for both stimulus-specific long-term memory (LTM) formation and extinction. It, however, remains unknown which components of memory formation Dnmts regulate (e.g., associative vs. non-associative) and in what context (e.g., varying training conditions). Here, we address these aspects in order to clarify the role of Dnmt-mediated DNA methylation in memory formation. We used a pharmacological Dnmt inhibitor and classical appetitive conditioning in the honeybee Apis mellifera, a well characterized model for classical conditioning. We quantified the effect of DNA methylation on naïve odor and sugar responses, and on responses following olfactory reward conditioning. We show that (1) Dnmts do not influence naïve odor or sugar responses, (2) Dnmts do not affect the learning of new stimuli, but (3) Dnmts influence odor-coding, i.e., 'correct' (stimulus-specific) LTM formation. Particularly, Dnmts reduce memory specificity when experience is low (one-trial training), and increase memory specificity when experience is high (multiple-trial training), generating an ecologically more useful response to learning. (4) In reversal learning conditions, Dnmts are involved in regulating both excitatory (re-acquisition) and inhibitory (forgetting) processes.

Do emotional stimuli enhance or impede recall relative to neutral stimuli? An investigation of two "false memory" tasks.

PubMed

Monds, Lauren A; Paterson, Helen M; Kemp, Richard I

2017-09-01

Many eyewitness memory situations involve negative and distressing events; however, many studies investigating "false memory" phenomena use neutral stimuli only. The aim of the present study was to determine how both the Deese-Roediger-McDermott (DRM) procedure and the Misinformation Effect Paradigm tasks were related to each other using distressing and neutral stimuli. Participants completed the DRM (with negative and neutral word lists) and viewed a distressing or neutral film. Misinformation for the film was introduced and memory was assessed. Film accuracy and misinformation susceptibility were found to be greater for those who viewed the distressing film relative to the neutral film. Accuracy responses on both tasks were related, however, susceptibility to the DRM illusion and Misinformation Effect were not. The misinformation findings support the Paradoxical Negative Emotion (PNE) hypothesis that negative stimuli will lead to remembering more accurate details but also greater likelihood of memory distortion. However, the PNE hypothesis was not supported for the DRM results. The findings also suggest that the DRM and Misinformation tasks are not equivalent and may have differences in underlying mechanisms. Future research should focus on more ecologically valid methods of assessing false memory.

Critical Period of Memory Enhancement during Taste Avoidance Conditioning in Lymnaea stagnalis

PubMed Central

Sunada, Hiroshi; Lukowiak, Ken; Sakakibara, Manabu

2013-01-01

The present study investigated the optimal training procedure leading to long-lasting taste avoidance behavior in Lymnaea. A training procedure comprising 5 repeated pairings of a conditional stimulus (CS, sucrose), with an unconditional stimulus (US, a tactile stimulation to the animal’s head), over a 4-day period resulted in an enhanced memory formation than 10 CS-US repeated pairings over a 2-day period or 20 CS-US repeated pairings on a single day. Backward conditioning (US-CS) pairings did not result in conditioning. Thus, this taste avoidance conditioning was CS-US pairing specific. Food avoidance behavior was not observed following training, however, if snails were immediately subjected to a cold-block (4°C for 10 min). It was critical that the cold-block be applied within 10 min to block long-term memory (LTM) formation. Further, exposure to the cold-block 180 min after training also blocked both STM and LTM formation. The effects of the cold-block on subsequent learning and memory formation were also examined. We found no long lasting effects of the cold-block on subsequent memory formation. If protein kinase C was activated before the conditioning paradigm, snails could still acquire STM despite exposure to the cold-block. PMID:24098373

Gene repressive mechanisms in the mouse brain involved in memory formation

PubMed Central

Yu, Nam-Kyung; Kaang, Bong-Kiun

2016-01-01

Gene regulation in the brain is essential for long-term plasticity and memory formation. Despite this established notion, the quantitative translational map in the brain during memory formation has not been reported. To systematically probe the changes in protein synthesis during memory formation, our recent study exploited ribosome profiling using the mouse hippocampal tissues at multiple time points after a learning event. Analysis of the resulting database revealed novel types of gene regulation after learning. First, the translation of a group of genes was rapidly suppressed without change in mRNA levels. At later time points, the expression of another group of genes was downregulated through reduction in mRNA levels. This reduction was predicted to be downstream of inhibition of ESR1 (Estrogen Receptor 1) signaling. Overexpressing Nrsn1, one of the genes whose translation was suppressed, or activating ESR1 by injecting an agonist interfered with memory formation, suggesting the functional importance of these findings. Moreover, the translation of genes encoding the translational machineries was found to be suppressed, among other genes in the mouse hippocampus. Together, this unbiased approach has revealed previously unidentified characteristics of gene regulation in the brain and highlighted the importance of repressive controls. [BMB Reports 2016; 49(4): 199-200] PMID:26949020