WorldWideScience

Sample records for experimentally-induced false memories

  1. Confabulation versus experimentally induced false memories in Korsakoff patients.

    Science.gov (United States)

    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.

  2. False memories for dissonance inducing events.

    Science.gov (United States)

    Rodriguez, Dario N; Strange, Deryn

    2015-01-01

    Memories serve as a "database" of the self and people often produce distorted memories that support their self-concepts. One, surprisingly untested, possibility is that cognitive dissonance may be one mechanism by which people may misremember their past. We tested this hypothesis using an induced-compliance paradigm: participants either chose or were forced to write a counterattitudinal essay supporting a tuition increase and were afforded the opportunity to reduce dissonance via attitude shift or denial of responsibility. They then reported their memories for the experimental instructions and their initial attitudes (assessed two days prior to the laboratory session). Participants who chose to write the essay exhibited the predicted attitude-shift effect, and were more likely to misremember their initial attitudes and the experimental instruction than those who were forced to write the essay. Overall, our results provide evidence that cognitive dissonance may yield memory distortion, filling a significant gap in the motivated cognition and memory literatures.

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

    Science.gov (United States)

    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.

  4. Explaining the Development of False Memories.

    Science.gov (United States)

    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…

  5. Experimentally-induced dissociation impairs visual memory.

    Science.gov (United States)

    Brewin, Chris R; Mersaditabari, Niloufar

    2013-12-01

    Dissociation is a phenomenon common in a number of psychological disorders and has been frequently suggested to impair memory for traumatic events. In this study we explored the effects of dissociation on visual memory. A dissociative state was induced experimentally using a mirror-gazing task and its short-term effects on memory performance were investigated. Sixty healthy individuals took part in the experiment. Induced dissociation impaired visual memory performance relative to a control condition; however, the degree of dissociation was not associated with lower memory scores in the experimental group. The results have theoretical and practical implications for individuals who experience frequent dissociative states such as patients with posttraumatic stress disorder (PTSD). Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Experimental Investigation of the Time Course Effects of Acute Exercise on False Episodic Memory

    Directory of Open Access Journals (Sweden)

    Ali Siddiqui

    2018-06-01

    Full Text Available Previous experimental work suggests that acute exercise may positively influence the accurate recall of past episodic events. However, few studies have examined whether acute exercise also reduces the number of false episodic memories. We evaluated this paradigm in conjunction with an examination of the temporal effects of acute exercise, which have previously been shown to play an important role in subserving episodic memory function. Twenty young adults participated in three experimental visits, including a non-exercise control visit, a visit involving an acute bout (20 min of moderate-intensity exercise occurring prior to the memory task, and a visit involving an acute bout of exercise occurring during the encoding of the memory task. All visits were counterbalanced and occurred at least 24 h apart. The Deese–Roediger–McDermott (DRM Paradigm, involving a separate word list trial for each visit, was employed to assess accurate and false episodic memory recall. For each visit, a short-term (immediate recall and a long-term (25-min delay memory recall was assessed. For both time points, the visit that involved exercise prior to encoding resulted in better short-term and long-term memory function (F(2 = 11.56, p < 0.001, η2p = 0.38. For both time points, the control visit resulted in a greater number of false memories. These findings suggest that acute moderate-intensity exercise may help to increase the accurate recall of past episodic memories and may help to reduce the rate of false memories.

  7. With sadness comes accuracy; with happiness, false memory: mood and the false memory effect.

    Science.gov (United States)

    Storbeck, Justin; Clore, Gerald L

    2005-10-01

    The Deese-Roediger-McDermott paradigm lures people to produce false memories. Two experiments examined whether induced positive or negative moods would influence this false memory effect. The affect-as-information hypothesis predicts that, on the one hand, positive affective cues experienced as task-relevant feedback encourage relational processing during encoding, which should enhance false memory effects. On the other hand, negative affective cues are hypothesized to encourage item-specific processing at encoding, which should discourage such effects. The results of Experiment 1 are consistent with these predictions: Individuals in negative moods were significantly less likely to show false memory effects than those in positive moods or those whose mood was not manipulated. Experiment 2 introduced inclusion instructions to investigate whether moods had their effects at encoding or retrieval. The results replicated the false memory finding of Experiment 1 and provide evidence that moods influence the accessibility of lures at encoding, rather than influencing monitoring at retrieval of whether lures were actually presented.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  10. Sleep loss produces false memories.

    Directory of Open Access Journals (Sweden)

    Susanne Diekelmann

    Full Text Available People sometimes claim with high confidence to remember events that in fact never happened, typically due to strong semantic associations with actually encoded events. Sleep is known to provide optimal neurobiological conditions for consolidation of memories for long-term storage, whereas sleep deprivation acutely impairs retrieval of stored memories. Here, focusing on the role of sleep-related memory processes, we tested whether false memories can be created (a as enduring memory representations due to a consolidation-associated reorganization of new memory representations during post-learning sleep and/or (b as an acute retrieval-related phenomenon induced by sleep deprivation at memory testing. According to the Deese, Roediger, McDermott (DRM false memory paradigm, subjects learned lists of semantically associated words (e.g., "night", "dark", "coal",..., lacking the strongest common associate or theme word (here: "black". Subjects either slept or stayed awake immediately after learning, and they were either sleep deprived or not at recognition testing 9, 33, or 44 hours after learning. Sleep deprivation at retrieval, but not sleep following learning, critically enhanced false memories of theme words. This effect was abolished by caffeine administration prior to retrieval, indicating that adenosinergic mechanisms can contribute to the generation of false memories associated with sleep loss.

  11. Arousal—But Not Valence—Reduces False Memories at Retrieval

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Chiara Mirandola

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  15. Recollection Rejection: How Children Edit Their False Memories.

    Science.gov (United States)

    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…

  16. False memories and confabulation.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  18. Illusions and delusions: relating experimentally-induced false memories to anomalous experiences and ideas

    Directory of Open Access Journals (Sweden)

    Philip R Corlett

    2009-11-01

    Full Text Available The salience hypothesis of psychosis rests on a simple but profound observation that subtle alterations in the way that we perceive and experience stimuli have important consequences for how important these stimuli become for us, how much they draw our attention, how they embed themselves in our memory and, ultimately, how they shape our beliefs. We put forward the idea that a classical memory illusion – the Deese-Roediger-McDermott (DRM effect – offers a useful way of exploring processes related to such aberrant belief formation. The illusion occurs when, as a consequence of its relationship to previous stimuli, a stimulus is asserted to be remembered even when has not been previously presented. Such illusory familiarity is thought to be generated by the surprising fluency with which the stimulus is processed. In this respect, the illusion relates directly to the salience hypothesis and may share common cognitive underpinnings with aberrations of perception and attribution that are found in psychosis. In this paper, we explore the theoretical importance of this experimentally-induced illusion in relation to the salience model of psychosis. We present data showing that, in healthy volunteers, the illusion relates directly to self reported anomalies of experience and magical thinking. We discuss this finding in terms of the salience hypothesis and of a broader Bayesian framework of perception and cognition which emphasizes the salience both of predictable and unpredictable experiences..

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

    Science.gov (United States)

    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.

  20. Creating a false memory in the hippocampus.

    Science.gov (United States)

    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.

  1. Arousal?But Not Valence?Reduces False Memories at Retrieval

    OpenAIRE

    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 indu...

  2. False memories for aggressive acts.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  5. The corrective effects of warning on false memories in the DRM paradigm are limited to full attention conditions.

    Science.gov (United States)

    Peters, Maarten J V; Jelicic, Marko; Gorski, Benny; Sijstermans, Kevin; Giesbrecht, Timo; Merckelbach, Harald

    2008-10-01

    Effects of attention control and forewarning on the activation and monitoring of experimentally induced false memories in the Deese/Roediger-McDermott paradigm were investigated in a young adult sample (N=77). We found that reducing the degree of attention during encoding led to a decrease in veridical recall and an increase in non-presented critical lure intrusions. This effect could not be counteracted by a forewarning instruction. However, these findings did not emerge in a (retrieval supportive) recognition task. It seems that divided attention increases false recall when attention control and forewarning have to compete for limited cognitive resources in a generative free recall as opposed to a retrieval supportive recognition task. Forewarning instructions do not always protect young adults against experimentally induced false memories.

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

    Science.gov (United States)

    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.

  7. Individual differences in false memory from misinformation: cognitive factors.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    OpenAIRE

    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 be manipulated factorially. False memories increased with age for unpresented semantic associates of word lists, and net accuracy (the ratio of true...

  10. The relationship between DRM and misinformation false memories

    OpenAIRE

    Zhu, B; Chen, C; Loftus, EF; Lin, C; Dong, Q

    2013-01-01

    This research investigated the relationship between false memories induced by two different paradigms (misinformation and Deese-Roediger-McDermott [DRM]). The misinformation effect refers to the phenomenon that a person's recollection of a witnessed event can be altered after exposure to misleading information about the event. DRM false memory represents the intrusion of words that are semantically related but not actually presented in the study session. Subjects (N = 432) completed both misi...

  11. Differentiating true and false schematic memories in older adults.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  13. Sleep reduces false memory in healthy older adults.

    Science.gov (United States)

    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.

  14. False memories in highly superior autobiographical memory individuals

    Science.gov (United States)

    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

  15. Working memory affects false memory production for emotional events.

    Science.gov (United States)

    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.

  16. Reduced False Memory after Sleep

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  19. True photographs and false memories.

    Science.gov (United States)

    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.

  20. Working memory predicts the rejection of false memories.

    Science.gov (United States)

    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.

  1. False memories and memory confidence in borderline patients.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  3. False memories in social anxiety disorder

    Directory of Open Access Journals (Sweden)

    PRISCILA DE CAMARGO PALMA

    Full Text Available Abstract Background False memories are memories of events that never occurred or that occurred, but not exactly as we recall. Events with emotional content are subject to false memories production similar to neutral events. However, individual differences, such as the level of maladjustment and emotional instability characteristics of Social Anxiety Disorder (SAD, may interfere in the production of false memories. Objectives This study aimed to assess the effect of emotion in memory performance for an event witnessed by participants with and without SAD. Methods Participants were 61 young adults with SAD and 76 without any symptoms of SAD who were randomly assigned to watch a story with or without emotional arousal. Participants answered a subjective scale of emotion about the story and a recognition memory test. Results Participants with SAD recovered more true memories and more false memories for the non-emotional version compared to the emotional version of the story. Overall, participants with SAD produced fewer false memories compared to those without SAD. Discussion This finding suggests that social anxiety may have a significant impact on emotional memory accuracy, which may assist in the development and improvement of techniques for therapeutic intervention.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  6. Priming analogical reasoning with false memories.

    Science.gov (United States)

    Howe, Mark L; Garner, Sarah R; Threadgold, Emma; Ball, Linden J

    2015-08-01

    Like true memories, false memories are capable of priming answers to insight-based problems. Recent research has attempted to extend this paradigm to more advanced problem-solving tasks, including those involving verbal analogical reasoning. However, these experiments are constrained inasmuch as problem solutions could be generated via spreading activation mechanisms (much like false memories themselves) rather than using complex reasoning processes. In three experiments we examined false memory priming of complex analogical reasoning tasks in the absence of simple semantic associations. In Experiment 1, we demonstrated the robustness of false memory priming in analogical reasoning when backward associative strength among the problem terms was eliminated. In Experiments 2a and 2b, we extended these findings by demonstrating priming on newly created homonym analogies that can only be solved by inhibiting semantic associations within the analogy. Overall, the findings of the present experiments provide evidence that the efficacy of false memory priming extends to complex analogical reasoning problems.

  7. Transient medial prefrontal perturbation reduces false memory formation.

    Science.gov (United States)

    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.

  8. False memories in highly superior autobiographical memory individuals

    OpenAIRE

    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 hi...

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

    Science.gov (United States)

    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

  10. Discrete emotion-congruent false memories in the DRM paradigm.

    Science.gov (United States)

    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).

  11. Sleep enhances false memories depending on general memory performance.

    Science.gov (United States)

    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.

  12. False memoryfalse memory: DRM errors are unrelated to the misinformation effect.

    Directory of Open Access Journals (Sweden)

    James Ost

    Full Text Available The DRM method has proved to be a popular and powerful, if controversial, way to study 'false memories'. One reason for the controversy is that the extent to which the DRM effect generalises to other kinds of memory error has been neither satisfactorily established nor subject to much empirical attention. In the present paper we contribute data to this ongoing debate. One hundred and twenty participants took part in a standard misinformation effect experiment, in which they watched some CCTV footage, were exposed to misleading post-event information about events depicted in the footage, and then completed free recall and recognition tests. Participants also completed a DRM test as an ostensibly unrelated filler task. Despite obtaining robust misinformation and DRM effects, there were no correlations between a broad range of misinformation and DRM effect measures (mean r  = -.01. This was not due to reliability issues with our measures or a lack of power. Thus DRM 'false memories' and misinformation effect 'false memories' do not appear to be equivalent.

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

    Science.gov (United States)

    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.

  14. Can False Memories Prime Problem Solutions?

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  19. False Memories and Reproductive Imagination: Ricoeur’s Phenomenology of Memory

    Directory of Open Access Journals (Sweden)

    Man-to TANG

    2015-06-01

    Full Text Available In cognitive psychology, a false memory refers to a fabricated or distorted recollection of an event that did not actually happen. Both ‘memory-distortion’ and ‘false memory creation’ refer to the processes of recollection in which the recollected events are not actually happened. This paper has three aims: (1 to examine Ricoeur’s analysis of memory and imagination; (2 to explain and reinforce the constructive role of memory; (3 to show in what manner the first two aims lead to the conclusion that the phenomena of ‘distorted or false memory creation’ are reproductive because the nature of recollection is constructive in the sense of representation of past. In this regard, Ricoeur’s trajectory not only displaces the essential structure of memory and imagination behind the curtain of their distinction and connection, but also contributes to the debates in cognitive psychology.

  20. Making up History: False Memories of Fake News Stories

    Directory of Open Access Journals (Sweden)

    Danielle C. Polage

    2012-05-01

    Full Text Available Previous research has shown that information that is repeated is more likely to be rated as true than information that has not been heard before. The current experiment examines whether familiarity with false news stories would increase rates of truthfulness and plausibility for these events. Further, the experiment tested whether false stories that were familiar would result in the creation of a false memory of having heard the story outside of the experiment. Participants were exposed to false new stories, each portrayed by the investigator as true news stories. After a five week delay, participants who had read the false experimental stories rated them as more truthful and more plausible than participants who had not been exposed to the stories. In addition, there was evidence of the creation of false memories for the source of the news story. Participants who had previously read about the stories were more likely to believe that they had heard the false stories from a source outside the experiment. These results suggest that repeating false claims will not only increase their believability but may also result in source monitoring errors.

  1. Rapid induction of false memory for pictures.

    Science.gov (United States)

    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.

  2. On the susceptibility of adaptive memory to false memory illusions.

    Science.gov (United States)

    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.

  3. False Memories for Affective Information in Schizophrenia.

    Science.gov (United States)

    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  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.

  4. False Memories for Affective Information in Schizophrenia

    Science.gov (United States)

    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 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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  7. The semantics of emotion in false memory.

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Porter, Stephen; ten Brinke, Leanne; Riley, Sean N; Baker, Alysha

    2014-01-01

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

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

    Science.gov (United States)

    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.

  11. Emotions and false memories: valence or arousal?

    Science.gov (United States)

    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.

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

    NARCIS (Netherlands)

    Otgaar, H.; Verschuere, B.; Meijer, E.H.; van Oorsouw, K.

    2012-01-01

    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

  13. Complementarity in false memory illusions.

    Science.gov (United States)

    Brainerd, C J; Reyna, V F

    2018-03-01

    For some years, the DRM illusion has been the most widely studied form of false memory. The consensus theoretical interpretation is that the illusion is a reality reversal, in which certain new words (critical distractors) are remembered as though they are old list words rather than as what they are-new words that are similar to old ones. This reality-reversal interpretation is supported by compelling lines of evidence, but prior experiments are limited by the fact that their memory tests only asked whether test items were old. We removed that limitation by also asking whether test items were new-similar. This more comprehensive methodology revealed that list words and critical distractors are remembered quite differently. Memory for list words is compensatory: They are remembered as old at high rates and remembered as new-similar at very low rates. In contrast, memory for critical distractors is complementary: They are remembered as both old and new-similar at high rates, which means that the DRM procedure induces a complementarity illusion rather than a reality reversal. The conjoint recognition model explains complementarity as a function of three retrieval processes (semantic familiarity, target recollection, and context recollection), and it predicts that complementarity can be driven up or down by varying the mix of those processes. Our experiments generated data on that prediction and introduced a convenient statistic, the complementarity ratio, which measures (a) the level of complementarity in memory performance and (b) whether its direction is reality-consistent or reality-reversed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  14. False memory for context activates the parahippocampal cortex.

    Science.gov (United States)

    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.

  15. Compelling Untruths: Content Borrowing and Vivid False Memories

    Science.gov (United States)

    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…

  16. Experimentally Evoking Nonbelieved Memories for Childhood Events

    Science.gov (United States)

    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%…

  17. How does negative emotion cause false memories?

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  19. False memory and level of processing effect: an event-related potential study.

    Science.gov (United States)

    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.

  20. Can false memories be created through nonconscious processes?

    Science.gov (United States)

    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.

  1. False memories for affective information in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Beth Fairfield

    2016-11-01

    Full Text Available 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, twenty-four patients and twenty-four 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 (p0.05 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.

  2. Semantic representations in the temporal pole predict false memories.

    Science.gov (United States)

    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.

  3. Semantic representations in the temporal pole predict false memories

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  5. Emotion and false memory: The context-content paradox.

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

  7. True and False Memories, Parietal Cortex, and Confidence Judgments

    Science.gov (United States)

    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).…

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

    Science.gov (United States)

    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…

  9. Misattribution, false recognition and the sins of memory.

    Science.gov (United States)

    Schacter, D L; Dodson, C S

    2001-09-29

    Memory is sometimes a troublemaker. Schacter has classified memory's transgressions into seven fundamental 'sins': transience, absent-mindedness, blocking, misattribution, suggestibility, bias and persistence. This paper focuses on one memory sin, misattribution, that is implicated in false or illusory recognition of episodes that never occurred. We present data from cognitive, neuropsychological and neuroimaging studies that illuminate aspects of misattribution and false recognition. We first discuss cognitive research examining possible mechanisms of misattribution associated with false recognition. We also consider ways in which false recognition can be reduced or avoided, focusing in particular on the role of distinctive information. We next turn to neuropsychological research concerning patients with amnesia and Alzheimer's disease that reveals conditions under which such patients are less susceptible to false recognition than are healthy controls, thus providing clues about the brain mechanisms that drive false recognition. We then consider neuroimaging studies concerned with the neural correlates of true and false recognition, examining when the two forms of recognition can and cannot be distinguished on the basis of brain activity. Finally, we argue that even though misattribution and other memory sins are annoying and even dangerous, they can also be viewed as by-products of adaptive features of memory.

  10. Lateralised sleep spindles relate to false memory generation.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  12. A mega-analysis of memory reports from eight peer-reviewed false memory implantation studies.

    Science.gov (United States)

    Scoboria, Alan; Wade, Kimberley A; Lindsay, D Stephen; Azad, Tanjeem; Strange, Deryn; Ost, James; Hyman, Ira E

    2017-02-01

    Understanding that suggestive practices can promote false beliefs and false memories for childhood events is important in many settings (e.g., psychotherapeutic, medical, and legal). The generalisability of findings from memory implantation studies has been questioned due to variability in estimates across studies. Such variability is partly due to false memories having been operationalised differently across studies and to differences in memory induction techniques. We explored ways of defining false memory based on memory science and developed a reliable coding system that we applied to reports from eight published implantation studies (N = 423). Independent raters coded transcripts using seven criteria: accepting the suggestion, elaboration beyond the suggestion, imagery, coherence, emotion, memory statements, and not rejecting the suggestion. Using this scheme, 30.4% of cases were classified as false memories and another 23% were classified as having accepted the event to some degree. When the suggestion included self-relevant information, an imagination procedure, and was not accompanied by a photo depicting the event, the memory formation rate was 46.1%. Our research demonstrates a useful procedure for systematically combining data that are not amenable to meta-analysis, and provides the most valid estimate of false memory formation and associated moderating factors within the implantation literature to date.

  13. False memory production :effects of self-consistent false information and motivated cognition

    OpenAIRE

    Brown, Martha

    1996-01-01

    Remembrance of one's personal past and the development of false memories have recently received intense public scrutiny. Based upon self-schema (Markus, 1977) and selfverification (Swann, 1987) theories, two studies were conducted to investigate the hypothesis that a self-schema guides cognitive processing of self-relevant information and thereby influences the construction of a memory that includes false information, particularly more so if this information is self-schema consistent than ...

  14. Temporal lobe cortical electrical stimulation during the encoding and retrieval phase reduces false memories.

    Directory of Open Access Journals (Sweden)

    Paulo S Boggio

    Full Text Available A recent study found that false memories were reduced by 36% when low frequency repetitive transcranial magnetic stimulation (rTMS was applied to the left anterior temporal lobe after the encoding (study phase. Here we were interested in the consequences on a false memory task of brain stimulation throughout the encoding and retrieval task phases. We used transcranial direct current stimulation (tDCS because it has been shown to be a useful tool to enhance cognition. Specifically, we examined whether tDCS can induce changes in a task assessing false memories. Based on our preliminary results, three conditions of stimulation were chosen: anodal left/cathodal right anterior temporal lobe (ATL stimulation ("bilateral stimulation"; anodal left ATL stimulation (with a large contralateral cathodal electrode--referred as "unilateral stimulation" and sham stimulation. Our results showed that false memories were reduced significantly after the two active conditions (unilateral and bilateral stimulation as compared with sham stimulation. There were no significant changes in veridical memories. Our findings show that false memories are reduced by 73% when anodal tDCS is applied to the anterior temporal lobes throughout the encoding and retrieval stages, suggesting a possible strategy for improving certain aspects of learning.

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

    Science.gov (United States)

    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).

  16. False memories in children and adults: age, distinctiveness, and subjective experience.

    Science.gov (United States)

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

    2002-09-01

    This study investigated developmental trends associated with the Deese/Roediger-McDermott false-memory effect, the role of distinctive information in false-memory formation, and participants' subjective experience of true and false memories. Children (5- and 7-year-olds) and adults studied lists of semantically associated words. Half of the participants studied words alone, and half studied words accompanied by pictures. There were significant age differences in recall (5-year-olds evinced more false memories than did adults) but not in recognition of critical lures. Distinctive information reduced false memory for all age groups. Younger children provided with distinctive information, and older children and adults regardless of whether they viewed distinctive information, expressed higher levels of confidence in true than in false memories. Source attributions did not significantly differ between true and false memories. Implications for theories of false memory and memory development are discussed.

  17. Sadder and less accurate? False memory for negative material in depression.

    Science.gov (United States)

    Joormann, Jutta; Teachman, Bethany A; Gotlib, Ian H

    2009-05-01

    Previous research has demonstrated that induced sad mood is associated with increased accuracy of recall in certain memory tasks; the effects of clinical depression, however, are likely to be quite different. The authors used the Deese-Roediger-McDermott paradigm to examine the impact of clinical depression on erroneous recall of neutral and/or emotional stimuli. Specifically, they presented Deese-Roediger-McDermott lists that were highly associated with negative, neutral, or positive lures and compared participants diagnosed with major depressive disorder and nondepressed control participants on the accuracy of their recall of presented material and their false recall of never-presented lures. Compared with control participants, major depressive disorder participants recalled fewer words that had been previously presented but were more likely to falsely recall negative lures; there were no differences between major depressive disorder and control participants in false recall of positive or neutral lures. These findings indicate that depression is associated with false memories of negative material.

  18. Misattribution, false recognition and the sins of memory.

    OpenAIRE

    Schacter, D L; Dodson, C S

    2001-01-01

    Memory is sometimes a troublemaker. Schacter has classified memory's transgressions into seven fundamental 'sins': transience, absent-mindedness, blocking, misattribution, suggestibility, bias and persistence. This paper focuses on one memory sin, misattribution, that is implicated in false or illusory recognition of episodes that never occurred. We present data from cognitive, neuropsychological and neuroimaging studies that illuminate aspects of misattribution and false recognition. We firs...

  19. False memory in aging resulting from self-referential processing.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  1. A mega-analysis of memory reports from eight peer-reviewed false memory implantation studies

    OpenAIRE

    Scoboria, A.; Wade, Kimberley A.; Lindsay, D. S.; Azad, T.; Strange, D.; Ost, J.; Hyman, I. E.

    2016-01-01

    Understanding that suggestive practices can promote false beliefs and false memories forchildhood events is important in many settings (e.g., psychotherapeutic, medical, legal). The generalizability of findings from memory implantation studies has been questioned due to variability in estimates across studies. Such variability is partly due to false memories having been operationalized differently across studies and to differences in memory induction techniques. We explored ways of defining f...

  2. False memories with age: Neural and cognitive underpinnings.

    Science.gov (United States)

    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.

  3. False memories with age: neural and cognitive underpinnings

    Science.gov (United States)

    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

  4. Decreased susceptibility to false memories from misinformation in hormonal contraception users.

    Science.gov (United States)

    Petersen, Nicole; Patihis, Lawrence; Nielsen, Shawn E

    2015-01-01

    Sex hormones are increasingly implicated in memory formation. Recent literature has documented a relationship between hormones and emotional memory and sex differences, which are likely related to hormones, have long been demonstrated in a variety of mnemonic domains, including false memories. Hormonal contraception (HC), which alters sex hormones, has been associated with a bias towards gist memory and away from detailed memory in women who use it during an emotional memory task. Here, we investigated whether HC was associated with changes in susceptibility to false memories, which may be related to the formation of gist memories. We tested false memory susceptibility using two well-validated false memory paradigms: the Deese-Roediger-McDermott (DRM) task, and a story-based misinformation task. We found that hormonal contraceptive users were less susceptible to false memories compared to non-users in the misinformation task, and no differences were seen between groups on the DRM task. We hypothesise that the differences in false memories from the misinformation task may be related to hormonal contraceptive users' memory bias away from details, towards gist memory.

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

    Science.gov (United States)

    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.

  6. Long-term treadmill exercise-induced neuroplasticity and associated memory recovery of streptozotocin-induced diabetic rats: an experimenter blind, randomized controlled study.

    Science.gov (United States)

    You, Joshua Sung H; Kim, Chung-Ju; Kim, Mee Young; Byun, Yong Gwon; Ha, So Young; Han, Bong Suk; Yoon, Bum Chul

    2009-01-01

    We investigated a long-term exercise-induced neuroplasticity and spatial memory recovery in 15 rats in a treadmill as follows: normal control rats (NC), streptozotocin (STZ)-induced diabetic control rats (DC), and STZ-induced diabetic rats exercising in a treadmill (DE). As per the DE group, the running exercise in a treadmill was administered for 30 minutes a day for 6 weeks. Neuronal immediate-early gene (IEG) expression (c-Fos) in the hippocampus and radial arm maze (RAM) tests were measured and revealed that the c-Fos levels in DE were significantly higher than those in NC and DC (p memory performance scores, obtained from the RAM test, were significantly different among the three groups (p memory scores of NC and DE were higher than those of DC (p memory. This is the first experimental evidence in literature that supports the efficacy of exercise-induced neuroplasticity and spatial motor memory in diabetes care.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  9. The effects of experimental pain and induced optimism on working memory task performance.

    Science.gov (United States)

    Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

    2016-07-01

    Pain can interrupt and deteriorate executive task performance. We have previously shown that experimentally induced optimism can diminish the deteriorating effect of cold pressor pain on a subsequent working memory task (i.e., operation span task). In two successive experiments we sought further evidence for the protective role of optimism on pain-induced working memory impairments. We used another working memory task (i.e., 2-back task) that was performed either after or during pain induction. Study 1 employed a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain)×2 (pre-score vs. post-score) mixed factorial design. In half of the participants optimism was induced by the Best Possible Self (BPS) manipulation, which required them to write and visualize about a life in the future where everything turned out for the best. In the control condition, participants wrote and visualized a typical day in their life (TD). Next, participants completed either the cold pressor task (CPT) or a warm water control task (WWCT). Before (baseline) and after the CPT or WWCT participants working memory performance was measured with the 2-back task. The 2-back task measures the ability to monitor and update working memory representation by asking participants to indicate whether the current stimulus corresponds to the stimulus that was presented 2 stimuli ago. Study 2 had a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain) mixed factorial design. After receiving the BPS or control manipulation, participants completed the 2-back task twice: once with painful heat stimulation, and once without any stimulation (counter-balanced order). Continuous heat stimulation was used with temperatures oscillating around 1°C above and 1°C below the individual pain threshold. In study 1, the results did not show an effect of cold pressor pain on subsequent 2-back task performance. Results of study 2 indicated that heat pain impaired concurrent 2-back task performance. However, no evidence was found

  10. Effects of Aging and Education on False Memory

    Science.gov (United States)

    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…

  11. Can false memories be created through nonconscious processes?

    OpenAIRE

    Zeelenberg, René; Plomp, G.; Raaijmakers, Jeroen

    2003-01-01

    textabstractPresentation times of study words presented in the Deese/Roediger and McDermott (DRM) paradigm varied from 20 ms to 2000 ms per word in an attempt to replicate the false memory effect following extremely short presentations reported by J.G. Seamon, C.R. Luo and D.A. Gallo (1998). 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 ...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 false recognition in the aMCI group (41% ± 10%) was higher than the HC group. And the difference was significant (t = 4.207, P false memory in recall and questionnaire stages were positively correlated with FOK-EM in aMCI group (r = 0.563, 0.705, P false memory provoked by pictures. The deficit of memory monitoring in aMCI may be the foundation of false memory.

  14. Susceptibility to false memories in patients with ACoA aneurysm.

    Science.gov (United States)

    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.

  15. Post-learning arousal enhances veridical memory and reduces false memory in the Deese-Roediger-McDermott paradigm.

    Science.gov (United States)

    Nielson, Kristy A; Correro, Anthony N

    2017-10-01

    The Deese-Roediger-McDermott (DRM) paradigm examines false memory by introducing words associated with a non-presented 'critical lure' as memoranda, which typically causes the lures to be remembered as frequently as studied words. Our prior work has shown enhanced veridical memory and reduced misinformation effects when arousal is induced after learning (i.e., during memory consolidation). These effects have not been examined in the DRM task, or with signal detection analysis, which can elucidate the mechanisms underlying memory alterations. Thus, 130 subjects studied and then immediately recalled six DRM lists, one after another, and then watched a 3-min arousing (n=61) or neutral (n=69) video. Recognition tested 70min later showed that arousal induced after learning led to better delayed discrimination of studied words from (a) critical lures, and (b) other non-presented 'weak associates.' Furthermore, arousal reduced liberal response bias (i.e., the tendency toward accepting dubious information) for studied words relative to all foils, including critical lures and 'weak associates.' Thus, arousal induced after learning effectively increased the distinction between signal and noise by enhancing access to verbatim information and reducing endorsement of dubious information. These findings provide important insights into the cognitive mechanisms by which arousal modulates early memory consolidation processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Neural Global Pattern Similarity Underlies True and False Memories.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  18. Sleep does not cause false memories on a story-based test of suggestibility.

    Science.gov (United States)

    van Rijn, Elaine; Carter, Neil; McMurtrie, Hazel; Willner, Paul; Blagrove, Mark T

    2017-07-01

    Sleep contributes to the consolidation of memories. This process may involve extracting the gist of learned material at the expense of details. It has thus been proposed that sleep might lead to false memory formation. Previous research examined the effect of sleep on false memory using the Deese-Roediger-McDermott (DRM) paradigm. Mixed results were found, including increases and decreases in false memory after sleep relative to wake. It has been questioned whether DRM false memories occur by the same processes as real-world false memories. Here, the effect of sleep on false memory was investigated using the Gudjonsson Suggestibility Scale. Veridical memory deteriorated after a 12-h period of wake, but not after a 12-h period including a night's sleep. No difference in false memory was found between conditions. Although the literature supports sleep-dependent memory consolidation, the results here call into question extending this to a gist-based false memory effect. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  3. Relations between emotion and conscious recollection of true and false autobiographical memories: an investigation using lorazepam as a pharmacological tool.

    Science.gov (United States)

    Pernot-Marino, Elodie; Danion, Jean-Marie; Hedelin, Guy

    2004-08-01

    Conscious recollection for autobiographical memory is the subjective experience of reliving a personal event mentally. Its frequency is strongly influenced by the emotion experienced at the time of the event. We addressed the issue of whether conscious recollection for autobiographical memories is also influenced by the emotion experienced at the time of retrieval. We used lorazepam, a benzodiazepine, as a pharmacological tool to modulate this emotional experience. Autobiographical memories were recorded in eight healthy volunteers using a diary study methodology. Each day, four entries were made by each subject: two true events, one altered event and one false event. For each event, the subjects were asked to rate emotional variables at encoding and at retrieval. Two months later, there were two sessions of recognition tests during which the subjects received orally an acute administration of either lorazepam (0.038 mg/kg) or placebo using a cross-over design. Subjective states of awareness were assessed using the Remember/Know/Guess procedure. Compared to placebo, lorazepam increased levels of conscious recollection, as assessed by Remember responses, for both true and false memories and induced an overestimation of the personal significance and emotional intensity of past events. Structural equation modelling showed that this overestimation was causal in the increased frequency of conscious recollection. Our results provide experimental evidence that the frequency of conscious recollection for both true and false autobiographical memories is influenced by the emotion experienced at the time of retrieval.

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

    Science.gov (United States)

    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.

  5. The influence of perceptual similarity and individual differences on false memories in aging.

    Science.gov (United States)

    Dennis, Nancy A; Turney, Indira C

    2018-02-01

    Previous false memory research has suggested that older adults' false memories are based on an overreliance on gist processing in the absence of item-specific details. Yet, false memory studies have rarely taken into consideration the precise role of item-item similarity on the cognitive and neural mechanisms underlying perceptual false memories in older adults. In addition, work in our laboratory has suggested that when investigating the neural basis of false memories in older adults, it is equally as critical to take into account interindividual variability in behavior. With both factors in mind, the present study was the first to examine how both controlled, systematic differences in perceptual relatedness between targets and lures and individual differences in true and false recognition contribute to the neural basis of both true and false memories in older adults. Results suggest that between-subject variability in memory performance modulates neural activity in key regions associated with false memories in aging, whereas systematic differences in perceptual similarity did not modulate neural activity associated with false memories. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Development of False Memories in Bilingual Children and Adults

    Science.gov (United States)

    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…

  7. Visual Distinctiveness and the Development of Children's False Memories

    Science.gov (United States)

    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…

  8. Sleep deprivation increases formation of false memory.

    Science.gov (United States)

    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 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.

  9. Lexical Association and False Memory for Words in Two Cultures

    Science.gov (United States)

    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.…

  10. Effects of depressive disorder on false memory for emotional information.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  12. Emotional false memories in children with learning disabilities.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  15. Hemispheric asymmetries in discourse processing: evidence from false memories for lists and texts.

    Science.gov (United States)

    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.

  16. Exposure to suggestion and creation of false auditory memories.

    Science.gov (United States)

    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.

  17. On the susceptibility of adaptive memory to false memory illusions

    OpenAIRE

    Howe, M. L.; Derbish, M. H.

    2010-01-01

    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-rela...

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

    Science.gov (United States)

    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…

  19. Intellectual factors in false memories of patients with schizophrenia.

    Science.gov (United States)

    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.

  20. False memory susceptibility is correlated with categorisation ability in humans [v1; ref status: indexed, http://f1000r.es/3ty

    Directory of Open Access Journals (Sweden)

    Kathryn Hunt

    2014-07-01

    Full Text Available Our memory is often surprisingly inaccurate, with errors ranging from misremembering minor details of events to generating illusory memories of entire episodes. The pervasiveness of such false memories generates a puzzle: in the face of selection pressure for accuracy of memory, how could such systematic failures have persisted over evolutionary time? It is possible that memory errors are an inevitable by-product of our adaptive memories and that semantic false memories are specifically connected to our ability to learn rules and concepts and to classify objects by category memberships. Here we test this possibility using a standard experimental false memory paradigm and inter-individual variation in verbal categorisation ability. Indeed it turns out that the error scores are significantly negatively correlated, with those individuals scoring fewer errors on the categorisation test being more susceptible to false memory intrusions in a free recall test. A similar trend, though not significant, was observed between individual categorisation ability and false memory susceptibility in a word recognition task. Our results therefore indicate that false memories, to some extent, might be a by-product of our ability to learn rules, categories and concepts.

  1. Disfluent presentations lead to the creation of more false memories.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  3. Affective valence influences participant's susceptibility to false memories and illusory recollection.

    Science.gov (United States)

    Dehon, Hedwige; Larøi, Frank; Van der Linden, Martial

    2010-10-01

    This study examined the influence of emotional valence on the production of DRM false memories (Roediger & McDermott, 1995). Participants were presented with neutral, positive, or negative DRM lists for a later recognition (Experiment 1) or recall (Experiment 2) test. In both experiments, confidence and recollective experience (i.e., "Remember-Know" judgments; Tulving, 1985) were also assessed. Results consistently showed that, compared with neutral lists, affective lists induced more false recognition and recall of nonpresented critical lures. Moreover, although confidence ratings did not differ between the false remembering from the different kinds of lists, "Remember" responses were more often associated with negative than positive and neutral false remembering of the critical lures. In contrast, positive false remembering of the critical lures was more often associated with "Know" responses. These results are discussed in light of the Paradoxical Negative Emotion (PNE) hypothesis (Porter, Taylor, & ten Bricke, 2008). (PsycINFO Database Record (c) 2010 APA, all rights reserved).

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  6. Lexical association and false memory for words in two cultures.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  8. THE IMPACT OF EGO-INVOLVEMENT IN THE CREATION OF FALSE CHILDHOOD MEMORIES

    Directory of Open Access Journals (Sweden)

    Iris Zezelj

    2009-09-01

    Full Text Available An experiment employed a "familiar-informant false-narrative proce-dure" to examine the effects of ego involvement manipulation on the creation of false memories for suggested events. Our main sample consisted of 54 Serbian adolescent students. During the pre-testing stage, students’ parents (N=54 provided details from their children childhoods, which were used to create stimuli for the subsequent stages. Half of the participants were given an ego-involving suggestion- a short written statement that claimed that people with higher intelligence have a better and more detailed memory of their childhood. We hypothesized that ego-involved group would recollect more childhood events in general, create more false memories and be more confident in its’ authenticity and clarity. Implanted event was recognized as autobiographic by 24% respondents in the testing stage and by 44.4% respondents in the retesting stage. There were significant qualitative differences between authentic and false memories: authentic memories were assessed as more reliable and clearer than the false ones. Ego-involvement manipulation had no impact on the frequency or quality of false memories reported by the participants. Even though the specific ego-involvement manipulation was not successful, our findings suggest that other motivating strategies we employed pushed the respondents into accepting false memory suggestion in the retesting stage. Future research could benefit from testing more elaborate ego-involving procedures.

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

    Science.gov (United States)

    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.

  10. Effects of post-encoding stress on performance in the DRM false memory paradigm

    OpenAIRE

    Pardilla-Delgado, Enmanuelle; Alger, Sara E.; Cunningham, Tony J.; Kinealy, Brian; Payne, Jessica D.

    2016-01-01

    Numerous studies have investigated how stress impacts veridical memory, but how stress influences false memory formation remains poorly understood. In order to target memory consolidation specifically, a psychosocial stress (TSST) or control manipulation was administered following encoding of 15 neutral, semantically related word lists (DRM false memory task) and memory was tested 24 h later. Stress decreased recognition of studied words, while increasing false recognition of semantically rel...

  11. False memory susceptibility is correlated with categorisation ability in humans [v2; ref status: indexed, http://f1000r.es/4k0

    Directory of Open Access Journals (Sweden)

    Kathryn Hunt

    2014-10-01

    Full Text Available Our memory is often surprisingly inaccurate, with errors ranging from misremembering minor details of events to generating illusory memories of entire episodes. The pervasiveness of such false memories generates a puzzle: in the face of selection pressure for accuracy of memory, how could such systematic failures have persisted over evolutionary time? It is possible that memory errors are an inevitable by-product of our adaptive memories and that semantic false memories are specifically connected to our ability to learn rules and concepts and to classify objects by category memberships. Here we test this possibility using a standard experimental false memory paradigm and inter-individual variation in verbal categorisation ability. Indeed it turns out that the error scores are significantly negatively correlated, with those individuals scoring fewer errors on the categorisation test being more susceptible to false memory intrusions in a free recall test. A similar trend, though not significant, was observed between individual categorisation ability and false memory susceptibility in a word recognition task. Our results therefore indicate that false memories, to some extent, might be a by-product of our ability to learn rules, categories and concepts.

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

    OpenAIRE

    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 model...

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  15. False rumors and true belief: memory processes underlying children's errant reports of rumored events.

    Science.gov (United States)

    Principe, Gabrielle F; Haines, Brooke; Adkins, Amber; Guiliano, Stephanie

    2010-12-01

    Previous research has shown that overhearing an errant rumor--either from an adult or from peers--about an earlier experience can lead children to make detailed false reports. This study investigates the extent to which such accounts are driven by changes in children's memory representations or merely social demands that encourage the reporting of rumored information. This was accomplished by (a) using a warning manipulation that eliminated social pressures to report an earlier heard rumor and (b) examining the qualitative characteristics of children's false narratives of a rumored-but-nonexperienced event. Findings indicated that overheard rumors can induce sensory and contextual characteristics in memory that can lead children to develop genuine false beliefs in seeing rumored-but-nonexperienced occurrences. Such constructive tendencies were especially likely among 3- and 4-year-olds (relative to 5- and 6-year-olds) and when rumors were picked up from peers during natural social interactions (relative to when they were planted by an adult). (c) 2010 Elsevier Inc. All rights reserved.

  16. Development of the False-Memory Illusion

    Science.gov (United States)

    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…

  17. Discrete emotion-congruent false memories in the DRM paradigm

    OpenAIRE

    Bland, C.; Howe, M. L.; Knott, L.

    2016-01-01

    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 examined 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 stud...

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

    Science.gov (United States)

    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

  19. Mood-congruent false memories persist over time.

    Science.gov (United States)

    Knott, Lauren M; Thorley, Craig

    2014-01-01

    In this study, we examined the role of mood-congruency and retention interval on the false recognition of emotion laden items using the Deese/Roediger-McDermott (DRM) paradigm. Previous research has shown a mood-congruent false memory enhancement during immediate recognition tasks. The present study examined the persistence of this effect following a one-week delay. Participants were placed in a negative or neutral mood, presented with negative-emotion and neutral-emotion DRM word lists, and administered with both immediate and delayed recognition tests. Results showed that a negative mood state increased remember judgments for negative-emotion critical lures, in comparison to neutral-emotion critical lures, on both immediate and delayed testing. These findings are discussed in relation to theories of spreading activation and emotion-enhanced memory, with consideration of the applied forensic implications of such findings.

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

    Science.gov (United States)

    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.

  1. The role of rehearsal and generation in false memory creation.

    Science.gov (United States)

    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.

  2. 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.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Shannon McKeon

    Full Text Available 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.

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

    Science.gov (United States)

    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…

  6. Mood-congruent false memories persist over time

    OpenAIRE

    Knott, L.; Thorley, C.

    2014-01-01

    In this study we examined the role of mood-congruency and retention interval on the false recognition of emotion laden items using the Deese/Roediger-McDermott (DRM) paradigm. Previous research has shown a mood-congruent false memory enhancement during immediate recognition tasks. The present study examined the persistence of this effect following a one-week delay. Participants were placed in a negative or neutral mood, presented with negative-emotion and neutral-emotion DRM word lists, and a...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

  10. False Context Fear Memory in Rats

    Science.gov (United States)

    Bae, Sarah; Holmes, Nathan M.; Westbrook, R. Frederick

    2015-01-01

    Four experiments used rats to study false context fear memories. In Experiment 1, rats were pre-exposed to a distinctive chamber (context A) or to a control environment (context C), shocked after a delay in a second chamber (context B) and tested either in B or A. Rats pre-exposed to A froze just as much as control rats in B but more than control…

  11. 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.

    Science.gov (United States)

    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.

  12. Toxin-Induced Experimental Models of Learning and Memory Impairment.

    Science.gov (United States)

    More, Sandeep Vasant; Kumar, Hemant; Cho, Duk-Yeon; Yun, Yo-Sep; Choi, Dong-Kug

    2016-09-01

    Animal models for learning and memory have significantly contributed to novel strategies for drug development and hence are an imperative part in the assessment of therapeutics. Learning and memory involve different stages including acquisition, consolidation, and retrieval and each stage can be characterized using specific toxin. Recent studies have postulated the molecular basis of these processes and have also demonstrated many signaling molecules that are involved in several stages of memory. Most insights into learning and memory impairment and to develop a novel compound stems from the investigations performed in experimental models, especially those produced by neurotoxins models. Several toxins have been utilized based on their mechanism of action for learning and memory impairment such as scopolamine, streptozotocin, quinolinic acid, and domoic acid. Further, some toxins like 6-hydroxy dopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and amyloid-β are known to cause specific learning and memory impairment which imitate the disease pathology of Parkinson's disease dementia and Alzheimer's disease dementia. Apart from these toxins, several other toxins come under a miscellaneous category like an environmental pollutant, snake venoms, botulinum, and lipopolysaccharide. This review will focus on the various classes of neurotoxin models for learning and memory impairment with their specific mechanism of action that could assist the process of drug discovery and development for dementia and cognitive disorders.

  13. Activation of Imaginal Information on True and False Memories

    Science.gov (United States)

    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…

  14. Elucidating the neural correlates of related false memories using a systematic measure of perceptual relatedness.

    Science.gov (United States)

    Turney, Indira C; Dennis, Nancy A

    2017-02-01

    Previous memory research has exploited the perceptual similarities between lures and targets in order to evoke false memories. Nevertheless, while some studies have attempted to use lures that are objectively more similar than others, no study has systematically controlled for perceptual overlap between target and lure items and its role in accounting for false alarm rates or the neural processes underlying such perceptual false memories. The current study looked to fill this gap in the literature by using a face-morphing program to systematically control for the amount of perceptual overlap between lures and targets. Our results converge with previous studies in finding a pattern of differences between true and false memories. Most importantly, expanding upon this work, parametric analyses showed false memory activity increases with respect to the similarity between lures and targets within bilateral middle temporal gyri and right medial prefrontal cortex (mPFC). Moreover, this pattern of activation was unique to false memories and could not be accounted for by relatedness alone. Connectivity analyses further find that activity in the mPFC and left middle temporal gyrus co-vary, suggestive of gist-based monitoring within the context of false memories. Interestingly, neither the MTL nor the fusiform face area exhibited modulation as a function of target-lure relatedness. Overall, these results provide insight into the processes underlying false memories and further enhance our understanding of the role perceptual similarity plays in supporting false memories. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Memory for musical tones: the impact of tonality and the creation of false memories.

    Science.gov (United States)

    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.

  16. Memory for musical tones: The impact of tonality and the creation of false memories

    Directory of Open Access Journals (Sweden)

    Dominique T. Vuvan

    2014-06-01

    Full Text Available 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.

  17. Memory for musical tones: the impact of tonality and the creation of false memories

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  19. False memory and autism: what is the extent of the semantic deficits?

    OpenAIRE

    Valasek, Claudia Aparecida; Albuquerque, Pedro; Cordeiro, Quirino; Boggio, Paulo Sérgio

    2016-01-01

    In the recent decades, the interest in investigation of false memory has been amplified. However, just a few studies investigate the underlying electrophysiological components involved in true and false recognition, especially with regard to patients with autism. The aim of this article is to present the studies investigating false memory and semantic processing in people with typical development using electroencephalography in addition to (presenting) providing the restricted literature on t...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  4. Experimental sepsis impairs humoral memory in mice.

    Directory of Open Access Journals (Sweden)

    Christian Pötschke

    Full Text Available Patients with sepsis are often immune suppressed, and experimental mouse models of sepsis also display this feature. However, acute sepsis in mice is also characterized by a generalized B cell activation and plasma cell differentiation, resulting in a marked increase in serum antibody concentration. Its effects on humoral memory are not clearly defined. We measured the effects of experimental sepsis on long-term immunological memory for a defined antigen: we induced colon ascendens stent peritonitis (CASP 8 weeks after 2 rounds of immunization with ovalbumin. Four weeks later, the antigen-specific bone marrow plasma cell count had doubled in immunized non-septic animals, but remained unchanged in immunized septic animals. Sepsis also caused a decrease in antigen-specific serum antibody concentration. We conclude that sepsis weakens humoral memory by impeding the antigen-specific plasma cell pool's development, which is not complete 8 weeks after secondary immunization.

  5. SPATIAL MEMORY IMPAIRMENT AND HIPPOCAMPAL CELL LOSS INDUCED BY OKADAIC ACID (EXPERIMENTAL STUDY).

    Science.gov (United States)

    Chighladze, M; Dashniani, M; Beselia, G; Kruashvili, L; Naneishvili, T

    2016-01-01

    In the present study, we evaluated and compared effect of intracerebroventricular (ICV) and intrahippocampal bilateral microinjection of okadaic acid (OA) on spatial memory function assessed in one day water maze paradigm and hippocampal structure in rats. Rats were divided in following groups: Control(icv) - rats injected with ICV and aCSF; Control(hipp) - rats injected intrahippocampally with aCSF; OAicv - rats injected with ICV and OA; OAhipp - rats injected intrahippocampally with OA. Nissl staining of hippocampal sections showed that the pyramidal cell loss in OAhipp group is significantly higher than that in the OAicv. The results of behavioral experiments showed that ICV or intrahippocampal bilateral microinjection of OA did not affect learning process and short-term spatial memory but induced impairment in spatial long-term memory assessed in probe test performance 24 h after training. OA-induced spatial memory impairment may be attributed to the hippocampal cell death. Based on these results OA induced memory deficit and hippocampal cell loss in rat may be considered as a potential animal model for preclinical evaluation of antidementic drug activity.

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

    Science.gov (United States)

    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.

  7. Collective memory: a perspective from (experimental) clinical psychology.

    Science.gov (United States)

    Wessel, Ineke; Moulds, Michelle L

    2008-04-01

    This paper considers the concept of collective memory from an experimental clinical psychology perspective. Exploration of the term collective reveals a broad distinction between literatures that view collective memories as a property of groups (collectivistic memory) and those that regard these memories as a property of individuals who are, to a greater or lesser extent, an integral part of their social environment (social memory). First, we argue that the understanding of collectivistic memory phenomena may benefit from drawing parallels with current psychological models such as the self-memory system theory of individualistic autobiographical memory. Second, we suggest that the social memory literature may inform the study of trauma-related disorders. We argue that a factual focus induced by collaborative remembering may be beneficial to natural recovery in the immediate aftermath of trauma, and propose that shared remembering techniques may provide a useful addition to the treatment of post-traumatic stress disorder.

  8. Transient medial prefrontal perturbation reduces false memory formation

    NARCIS (Netherlands)

    Berkers, R.M.W.J.; Linden, M.H. van der; Almeida, R.F. de; Müller, N.C.J.; Bovy, L.; Dresler, M.; Morris, R.G.M.; Fernandez, G.S.E.

    2017-01-01

    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

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

    Science.gov (United States)

    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).

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

    OpenAIRE

    Dewhurst, Stephen A.; Barry, Christopher; Swannell, Ellen R.; Holmes, Selina J.; Bathurst, Gemma J.

    2007-01-01

    In three experiments, we investigated the effects of divided attention on false memory, using the Deese/Roediger-McDermott (DRM) paradigm. In Experiments 1 and 2, participants studied six DRM lists with full attention and six in one of two divided-attention conditions (random number generation or digit monitoring). Both divided-attention conditions increased false recall of related words (Experiment 1) but reduced false recognition (Experiment 2). These results were confirmed in Experiment 3,...

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

    Science.gov (United States)

    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.

  12. False memory and the associative network of happiness.

    Science.gov (United States)

    Koo, Minkyung; Oishi, Shigehiro

    2009-02-01

    This research examines the relationship between individuals' levels of life satisfaction and their associative networks of happiness. Study 1 measured European Americans' degree of false memory of happiness using the Deese-Roediger-McDermott paradigm. Scores on the Satisfaction With Life Scale predicted the likelihood of false memory of happiness but not of other lure words such as sleep . In Study 2, European American participants completed an association-judgment task in which they judged the extent to which happiness and each of 15 positive emotion terms were associated with each other. Consistent with Study 1's findings, chronically satisfied individuals exhibited stronger associations between happiness and other positive emotion terms than did unsatisfied individuals. However, Koreans and Asian Americans did not exhibit such a pattern regarding their chronic level of life satisfaction (Study 3). In combination, results suggest that there are important individual and cultural differences in the cognitive structure and associative network of happiness.

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

    Science.gov (United States)

    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.

  14. Can false memories be created through nonconscious processes?

    NARCIS (Netherlands)

    Raaijmakers, J.G.W.; Plomp, G.; Zeelenberg, R.

    2003-01-01

    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 Seamon, Luo, and Gallo (1998). Both in a within-subjects design

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

    Science.gov (United States)

    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:…

  16. Mood-congruent true and false memory: effects of depression.

    Science.gov (United States)

    Howe, Mark L; Malone, Catherine

    2011-02-01

    The Deese/Roediger-McDermott paradigm was used to investigate the effect of depression on true and false recognition. In this experiment true and false recognition was examined across positive, neutral, negative, and depression-relevant lists for individuals with and without a diagnosis of major depressive disorder. Results showed that participants with major depressive disorder falsely recognised significantly more depression-relevant words than non-depressed controls. These findings also parallel recent research using recall instead of recognition and show that there are clear mood congruence effects for depression on false memory performance. © 2011 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  19. Can false memories be created through nonconscious processes?

    NARCIS (Netherlands)

    R. Zeelenberg (René); G. Plomp; J.G.W. Raaijmakers (Jeroen)

    2003-01-01

    textabstractPresentation times of study words presented in the Deese/Roediger and McDermott (DRM) paradigm varied from 20 ms to 2000 ms per word in an attempt to replicate the false memory effect following extremely short presentations reported by J.G. Seamon, C.R. Luo and D.A. Gallo (1998). Both in

  20. Do Children "DRM" Like Adults? False Memory Production in Children

    Science.gov (United States)

    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…

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

    OpenAIRE

    Flegal, Kristin E.; Reuter-Lorenz, Patricia A.

    2014-01-01

    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 lon...

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Sara Cadavid

    Full Text Available 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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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)

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  13. Effects of Post-Encoding Stress on Performance in the DRM False Memory Paradigm

    Science.gov (United States)

    Pardilla-Delgado, Enmanuelle; Alger, Sara E.; Cunningham, Tony J.; Kinealy, Brian; Payne, Jessica D.

    2016-01-01

    Numerous studies have investigated how stress impacts veridical memory, but how stress influences false memory formation remains poorly understood. In order to target memory consolidation specifically, a psychosocial stress (TSST) or control manipulation was administered following encoding of 15 neutral, semantically related word lists (DRM false…

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

    Science.gov (United States)

    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.

  15. False Memories for Suggestions: The Impact of Conceptual Elaboration

    Science.gov (United States)

    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…

  16. False Memories for Shape Activate the Lateral Occipital Complex

    Science.gov (United States)

    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…

  17. An overview of the neuro-cognitive processes involved in the encoding, consolidation, and retrieval of true and false memories.

    Science.gov (United States)

    Straube, Benjamin

    2012-07-24

    Perception and memory are imperfect reconstructions of reality. These reconstructions are prone to be influenced by several factors, which may result in false memories. A false memory is the recollection of an event, or details of an episode, that did not actually occur. Memory formation comprises at least three different sub-processes: encoding, consolidation and the retrieval of the learned material. All of these sub-processes are vulnerable for specific errors and consequently may result in false memories. Whereas, processes like imagery, self-referential encoding or spreading activation can lead to the formation of false memories at encoding, semantic generalization during sleep and updating processes due to misleading post event information, in particular, are relevant at the consolidation stage. Finally at the retrieval stage, monitoring processes, which are assumed to be essential to reject false memories, are of specific importance. Different neuro-cognitive processes have been linked to the formation of true and false memories. Most consistently the medial temporal lobe and the medial and lateral prefrontal cortex have been reported with regard to the formation of true and false memories. Despite the fact that all phases entailing memory formation, consolidation of stored information and retrieval processes, are relevant for the forming of false memories, most studies focused on either memory encoding or retrieval. Thus, future studies should try to integrate data from all phases to give a more comprehensive view on systematic memory distortions. An initial outline is developed within this review to connect the different memory stages and research strategies.

  18. An overview of the neuro-cognitive processes involved in the encoding, consolidation, and retrieval of true and false memories

    Science.gov (United States)

    2012-01-01

    Perception and memory are imperfect reconstructions of reality. These reconstructions are prone to be influenced by several factors, which may result in false memories. A false memory is the recollection of an event, or details of an episode, that did not actually occur. Memory formation comprises at least three different sub-processes: encoding, consolidation and the retrieval of the learned material. All of these sub-processes are vulnerable for specific errors and consequently may result in false memories. Whereas, processes like imagery, self-referential encoding or spreading activation can lead to the formation of false memories at encoding, semantic generalization during sleep and updating processes due to misleading post event information, in particular, are relevant at the consolidation stage. Finally at the retrieval stage, monitoring processes, which are assumed to be essential to reject false memories, are of specific importance. Different neuro-cognitive processes have been linked to the formation of true and false memories. Most consistently the medial temporal lobe and the medial and lateral prefrontal cortex have been reported with regard to the formation of true and false memories. Despite the fact that all phases entailing memory formation, consolidation of stored information and retrieval processes, are relevant for the forming of false memories, most studies focused on either memory encoding or retrieval. Thus, future studies should try to integrate data from all phases to give a more comprehensive view on systematic memory distortions. An initial outline is developed within this review to connect the different memory stages and research strategies. PMID:22827854

  19. Valence and the development of immediate and long-term false memory illusions.

    Science.gov (United States)

    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.

  20. Degrading emotional memories induced by a virtual reality paradigm.

    Science.gov (United States)

    Cuperus, Anne A; Laken, Maarten; van den Hout, Marcel A; Engelhard, Iris M

    2016-09-01

    In Eye Movement and Desensitization and Reprocessing (EMDR) therapy, a dual-task approach is used: patients make horizontal eye movements while they recall aversive memories. Studies showed that this reduces memory vividness and/or emotionality. A strong explanation is provided by working memory theory, which suggests that other taxing dual-tasks are also effective. Experiment 1 tested whether a visuospatial task which was carried out while participants were blindfolded taxes working memory. Experiment 2 tested whether this task degrades negative memories induced by a virtual reality (VR) paradigm. In experiment 1, participants responded to auditory cues with or without simultaneously carrying out the visuospatial task. In experiment 2, participants recalled negative memories induced by a VR paradigm. The experimental group simultaneously carried out the visuospatial task, and a control group merely recalled the memories. Changes in self-rated memory vividness and emotionality were measured. The slowing down of reaction times due to the visuospatial task indicated that its cognitive load was greater than the load of the eye movements task in previous studies. The task also led to reductions in emotionality (but not vividness) of memories induced by the VR paradigm. Weaknesses are that only males were tested in experiment 1, and the effectiveness of the VR fear/trauma induction was not assessed with ratings of mood or intrusions in experiment 2. The results suggest that the visuospatial task may be applicable in clinical settings, and the VR paradigm may provide a useful method of inducing negative memories. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Effects of sulpiride on true and false memories of thematically related pictures and associated words in healthy volunteers

    Directory of Open Access Journals (Sweden)

    Regina V Guarnieri

    2016-03-01

    Full Text Available 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 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, placebo-controlled trial. The sulpiride group made 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 blockade in healthy volunteers can specifically increase the rate of false recognitions.

  2. Phytoceramide Shows Neuroprotection and Ameliorates Scopolamine-Induced Memory Impairment

    Directory of Open Access Journals (Sweden)

    Seikwan Oh

    2011-10-01

    Full Text Available The function and the role phytoceramide (PCER and phytosphingosine (PSO in the central nervous system has not been well studied. This study was aimed at investigating the possible roles of PCER and PSO in glutamate-induced neurotoxicity in cultured neuronal cells and memory function in mice. Phytoceramide showed neuro-protective activity in the glutamate-induced toxicity in cultured cortical neuronal cells. Neither phytosphingosine nor tetraacetylphytosphingosine (TAPS showed neuroproective effects in neuronal cells. PCER (50 mg/kg, p.o. recovered the scopolamine-induced reduction in step-through latency in the passive avoidance test; however, PSO did not modulate memory function on this task. The ameliorating effects of PCER on spatial memory were confirmed by the Morris water maze test. In conclusion, through behavioral and neurochemical experimental results, it was demonstrated that central administration of PCER produces amelioration of memory impairment. These results suggest that PCER plays an important role in neuroprotection and memory enhancement and PCER could be a potential new therapeutic agent for the treatment of neurodegenerative diseases such as Alzheimer’s disease.

  3. The organisation of musical semantic memory: evidence from false memories for familiar songs.

    Science.gov (United States)

    Sherman, Susan M; Kennerley, Jo

    2014-01-01

    By adapting a well-known paradigm for studying memory for words-the Deese-Roediger-McDermott or DRM paradigm (Deese, 1959, Roediger & McDermott, 1995)-the two experiments reported here explore memory for song titles and song clips. Participants were presented with five song titles (Experiment 1a) or five 30-second song clips (Experiment 1b) for each of nine popular artists (e.g., Robbie Williams). The most popular song identified for each artist in a pilot task was omitted from the sets of titles/clips. Following a distractor task, participants were asked to write down as many of the songs as they could recall. They were also asked to return a week later and complete a second recall task. Participants falsely recalled a significant number of the related but non-presented songs in both experiments and this increased a week later, while correct recall for presented items decreased. The results are discussed in terms of theory for musical memory as well as in the context of providing a novel method for exploring the organisation of musical memory.

  4. Acute effects of triazolam on false recognition.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  6. Neural correlates of true and false memory in mild cognitive impairment.

    Science.gov (United States)

    Sweeney-Reed, Catherine M; Riddell, Patricia M; Ellis, Judi A; Freeman, Jayne E; Nasuto, Slawomir J

    2012-01-01

    The goal of this research was to investigate the changes in neural processing in mild cognitive impairment. We measured phase synchrony, amplitudes, and event-related potentials in veridical and false memory to determine whether these differed in participants with mild cognitive impairment compared with typical, age-matched controls. Empirical mode decomposition phase locking analysis was used to assess synchrony, which is the first time this analysis technique has been applied in a complex cognitive task such as memory processing. The technique allowed assessment of changes in frontal and parietal cortex connectivity over time during a memory task, without a priori selection of frequency ranges, which has been shown previously to influence synchrony detection. Phase synchrony differed significantly in its timing and degree between participant groups in the theta and alpha frequency ranges. Timing differences suggested greater dependence on gist memory in the presence of mild cognitive impairment. The group with mild cognitive impairment had significantly more frontal theta phase locking than the controls in the absence of a significant behavioural difference in the task, providing new evidence for compensatory processing in the former group. Both groups showed greater frontal phase locking during false than true memory, suggesting increased searching when no actual memory trace was found. Significant inter-group differences in frontal alpha phase locking provided support for a role for lower and upper alpha oscillations in memory processing. Finally, fronto-parietal interaction was significantly reduced in the group with mild cognitive impairment, supporting the notion that mild cognitive impairment could represent an early stage in Alzheimer's disease, which has been described as a 'disconnection syndrome'.

  7. Neural Correlates of True and False Memory in Mild Cognitive Impairment

    Science.gov (United States)

    Sweeney-Reed, Catherine M.; Riddell, Patricia M.; Ellis, Judi A.; Freeman, Jayne E.; Nasuto, Slawomir J.

    2012-01-01

    The goal of this research was to investigate the changes in neural processing in mild cognitive impairment. We measured phase synchrony, amplitudes, and event-related potentials in veridical and false memory to determine whether these differed in participants with mild cognitive impairment compared with typical, age-matched controls. Empirical mode decomposition phase locking analysis was used to assess synchrony, which is the first time this analysis technique has been applied in a complex cognitive task such as memory processing. The technique allowed assessment of changes in frontal and parietal cortex connectivity over time during a memory task, without a priori selection of frequency ranges, which has been shown previously to influence synchrony detection. Phase synchrony differed significantly in its timing and degree between participant groups in the theta and alpha frequency ranges. Timing differences suggested greater dependence on gist memory in the presence of mild cognitive impairment. The group with mild cognitive impairment had significantly more frontal theta phase locking than the controls in the absence of a significant behavioural difference in the task, providing new evidence for compensatory processing in the former group. Both groups showed greater frontal phase locking during false than true memory, suggesting increased searching when no actual memory trace was found. Significant inter-group differences in frontal alpha phase locking provided support for a role for lower and upper alpha oscillations in memory processing. Finally, fronto-parietal interaction was significantly reduced in the group with mild cognitive impairment, supporting the notion that mild cognitive impairment could represent an early stage in Alzheimer’s disease, which has been described as a ‘disconnection syndrome’. PMID:23118992

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

    Science.gov (United States)

    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.

  9. Natural Conversations as a Source of False Memories in Children: Implications for the Testimony of Young Witnesses

    Science.gov (United States)

    Principe, Gabrielle F.; Schindewolf, Erica

    2012-01-01

    Research on factors that can affect the accuracy of children’s autobiographical remembering has important implications for understanding the abilities of young witnesses to provide legal testimony. In this article, we review our own recent research on one factor that has much potential to induce errors in children’s event recall, namely natural memory sharing conversations with peers and parents. Our studies provide compelling evidence that not only can the content of conversations about the past intrude into later memory but that such exchanges can prompt the generation of entirely false narratives that are more detailed than true accounts of experienced events. Further, our work show that deeper and more creative participation in memory sharing dialogues can boost the damaging effects of conversationally conveyed misinformation. Implications of this collection of findings for children’s testimony are discussed. PMID:23129880

  10. Forward Association, Backward Association, and the False-Memory Illusion

    Science.gov (United States)

    Brainerd, C. J.; Wright, Ron

    2005-01-01

    In the Deese-Roediger-McDermott false-memory illusion, forward associative strength (FAS) is unrelated to the strength of the illusion; this is puzzling, because high-FAS lists ought to share more semantic features with critical unpresented words than should low-FAS lists. The authors show that this null result is probably a truncated range…

  11. Towards Modeling False Memory With Computational Knowledge Bases.

    Science.gov (United States)

    Li, Justin; Kohanyi, Emma

    2017-01-01

    One challenge to creating realistic cognitive models of memory is the inability to account for the vast common-sense knowledge of human participants. Large computational knowledge bases such as WordNet and DBpedia may offer a solution to this problem but may pose other challenges. This paper explores some of these difficulties through a semantic network spreading activation model of the Deese-Roediger-McDermott false memory task. In three experiments, we show that these knowledge bases only capture a subset of human associations, while irrelevant information introduces noise and makes efficient modeling difficult. We conclude that the contents of these knowledge bases must be augmented and, more important, that the algorithms must be refined and optimized, before large knowledge bases can be widely used for cognitive modeling. Copyright © 2016 Cognitive Science Society, Inc.

  12. Dividing Attention Lowers Children's but Increases Adults' False Memories

    Science.gov (United States)

    Otgaar, Henry; Peters, Maarten; Howe, Mark L.

    2012-01-01

    The present study examined the impact of divided attention on children's and adults' neutral and negative true and false memories in a standard Deese/Roediger-McDermott paradigm. Children (7- and 11-year-olds; n = 126) and adults (n = 52) received 5 neutral and 5 negative Deese/Roediger-McDermott word lists; half of each group also received a…

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

    Science.gov (United States)

    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…

  14. Propranolol–induced Impairment of Contextual Fear Memory Reconsolidation in Rats: A similar Effect on Weak and Strong Recent and Remote Memories

    Science.gov (United States)

    Taherian, Fatemeh; Vafaei, Abbas Ali; Vaezi, Gholam Hassan; Eskandarian, Sharaf; Kashef, Adel; Rashidy-Pour, Ali

    2014-01-01

    Introduction Previous studies have demonstrated that the β-adrenergic receptor antagonist propranolol impairs fear memory reconsolidation in experimental animals. There are experimental parameters such as the age and the strength of memory that can interact with pharmacological manipulations of memory reconsolidation. In this study, we investigated the ability of the age and the strength of memory to influence the disrupting effects of propranolol on fear memory reconsolidation in rats. Methods The rats were trained in a contextual fear conditioning using two (weak training) or five (strong training) footshocks (1mA). Propranolol (10mg/kg) injection was immediately followed retrieval of either a one-day recent (weak or strong) or 36-day remote (weak or strong) contextual fear memories. Results We found that propranolol induced a long-lasting impairment of subsequent expression of recent and remote memories with either weak or strong strength. We also found no memory recovery after a weak reminder shock. Furthermore, no significant differences were found on the amount of memory deficit induced by propranolol among memories with different age and strength. Discussion Our data suggest that the efficacy of propranolol in impairing fear memory reconsolidation is not limited to the age or strength of the memory. PMID:25337385

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

    Directory of Open Access Journals (Sweden)

    Chen Hong

    2012-07-01

    Full Text Available Abstract 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.

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

    OpenAIRE

    Van Damme, I; Kaplan, RL; Levine, LJ; Loftus, EF

    2017-01-01

    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 o...

  17. Problems with a False Recognition Paradigm for Developmental Memory Research

    Science.gov (United States)

    Lindauer, Barbara K.; Paris, Scott G.

    1976-01-01

    Developmental changes in memory organization based on synonym and antonym relationships were examined in three experiments. Subjects were 64 second graders and 64 sixth graders. Some inadequacies of a false recognition paradigm for developmental research are identified and some alternative analyses are proposed. (Author/JH)

  18. Caffeine attenuates scopolamine-induced memory impairment in humans.

    Science.gov (United States)

    Riedel, W; Hogervorst, E; Leboux, R; Verhey, F; van Praag, H; Jolles, J

    1995-11-01

    Caffeine consumption can be beneficial for cognitive functioning. Although caffeine is widely recognized as a mild CNS stimulant drug, the most important consequence of its adenosine antagonism is cholinergic stimulation, which might lead to improvement of higher cognitive functions, particularly memory. In this study, the scopolamine model of amnesia was used to test the cholinergic effects of caffeine, administered as three cups of coffee. Subjects were 16 healthy volunteers who received 250 mg caffeine and 2 mg nicotine separately, in a placebo-controlled double-blind cross-over design. Compared to placebo, nicotine attenuated the scopolamine-induced impairment of storage in short-term memory and attenuated the scopolamine-induced slowing of speed of short-term memory scanning. Nicotine also attenuated the scopolamine-induced slowing of reaction time in a response competition task. Caffeine attenuated the scopolamine-induced impairment of free recall from short- and long-term memory, quality and speed of retrieval from long-term memory in a word learning task, and other cognitive and non-cognitive measures, such as perceptual sensitivity in visual search, reading speed, and rate of finger-tapping. On the basis of these results it was concluded that caffeine possesses cholinergic cognition enhancing properties. Caffeine could be used as a control drug in studies using the scopolamine paradigm and possibly also in other experimental studies of cognitive enhancers, as the effects of a newly developed cognition enhancing drug should at least be superior to the effects of three cups of coffee.

  19. Correction of false memory for associated word lists by collaborating groups.

    Science.gov (United States)

    Weigold, Arne; Russell, Elizabeth J; Natera, Sara N

    2014-01-01

    Collaborative inhibition is often observed for both correct and false memories. However, research examining the mechanisms by which collaborative inhibition occurs, such as retrieval disruption, reality monitoring, or group filtering, is lacking. In addition, the creation of the nominal groups (i.e., groups artificially developed by combining individuals' recall) necessary for examining collaborative inhibition do not use statistical best practices. Using the Deese-Roediger-McDermott paradigm, we examined percentages of correct and false memories in individuals, collaborative interactive groups, and correctly created nominal groups, as well as the processes that the collaborative interactive groups used to determine which memories to report. Results showed evidence of the collaborative inhibition effect. In addition, analyses of the collaborative interactive groups' discussions found that these groups wrote down almost all presented words but less than half of nonpresented critical words, after discussing them, with nonpresented critical words being stated to the group with lower confidence and rejected by other group members more often. Overall, our findings indicated support for the group filtering hypothesis.

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

    Science.gov (United States)

    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),…

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

    Science.gov (United States)

    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…

  2. Processes Underlying Developmental Reversals in False-Memory Formation: Comment on Brainerd, Reyna, and Ceci (2008)

    Science.gov (United States)

    Ghetti, Simona

    2008-01-01

    C. J. Brainerd, V. F. Reyna, and S. J. Ceci (2008) reviewed compelling evidence of developmental reversals in false-memory formation (i.e., younger children exhibit lower false-memory rates than do older children and adults) and proposed that this phenomenon depends on the development of gist processing (i.e., the ability to identify and process…

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

    Science.gov (United States)

    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.

  4. On the adaptive function of children's and adults' false memories.

    Science.gov (United States)

    Howe, Mark L; Wilkinson, Samantha; Garner, Sarah R; Ball, Linden J

    2016-09-01

    Recent research has shown that memory illusions can successfully prime both children's and adults' performance on complex, insight-based problems (compound remote associates tasks or CRATs). The current research aimed to clarify the locus of these priming effects. Like before, Deese-Roediger-McDermott (DRM) lists were selected to prime subsequent CRATs such that the critical lures were also the solution words to a subset of the CRATs participants attempted to solve. Unique to the present research, recognition memory tests were used and participants were either primed during the list study phase, during the memory test phase, or both. Across two experiments, primed problems were solved more frequently and significantly faster than unprimed problems. Moreover, when participants were primed during the list study phase, subsequent solution times and rates were considerably superior to those produced by those participants who were simply primed at test. Together, these are the first results to show that false-memory priming during encoding facilitates problem-solving in both children and adults.

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

    Science.gov (United States)

    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.

  6. Semantic similarity between old and new items produces false alarms in recognition memory.

    Science.gov (United States)

    Montefinese, Maria; Zannino, Gian Daniele; Ambrosini, Ettore

    2015-09-01

    In everyday life, human beings can report memories of past events that did not occur or that occurred differently from the way they remember them because memory is an imperfect process of reconstruction and is prone to distortion and errors. In this recognition study using word stimuli, we investigated whether a specific operationalization of semantic similarity among concepts can modulate false memories while controlling for the possible effect of associative strength and word co-occurrence in an old-new recognition task. The semantic similarity value of each new concept was calculated as the mean cosine similarity between pairs of vectors representing that new concept and each old concept belonging to the same semantic category. Results showed that, compared with (new) low-similarity concepts, (new) high-similarity concepts had significantly higher probability of being falsely recognized as old, even after partialling out the effect of confounding variables, including associative relatedness and lexical co-occurrence. This finding supports the feature-based view of semantic memory, suggesting that meaning overlap and sharing of semantic features (which are greater when more similar semantic concepts are being processed) have an influence on recognition performance, resulting in more false alarms for new high-similarity concepts. We propose that the associative strength and word co-occurrence among concepts are not sufficient to explain illusory memories but is important to take into account also the effects of feature-based semantic relations, and, in particular, the semantic similarity among concepts.

  7. Veridical and False Pictorial Memory in Individuals with and without Mental Retardation

    Science.gov (United States)

    Carlin, Michael T.; Toglia, Michael P.; Wakeford, Yvonne; Jakway, Allison; Sullivan, Kate; Hasel, Lisa

    2008-01-01

    Veridical and false pictorial recognition were assessed in individuals with mental retardation; groups were matched for MA and CA. Pictures were viewed in either a generative or static format at acquisition. The individuals with mental retardation and those in the MA-matched group had higher rates of false memories for critical items and lower hit…

  8. Scoliosis correction with shape-memory metal: results of an experimental study

    OpenAIRE

    Wever, D.; Elstrodt, J.; Veldhuizen, A.; v Horn, J.

    2001-01-01

    The biocompatibility and functionality of a new scoliosis correction device, based on the properties of the shape-memory metal nickel-titanium alloy, were studied. With this device, the shape recovery forces of a shape-memory metal rod are used to achieve a gradual three-dimensional scoliosis correction. In the experimental study the action of the new device was inverted: the device was used to induce a scoliotic curve instead of correcting one. Surgical procedures were performed in six pigs....

  9. Neural Activity during Encoding Predicts False Memories Created by Misinformation

    Science.gov (United States)

    Okado, Yoko; Stark, Craig E. L.

    2005-01-01

    False memories are often demonstrated using the misinformation paradigm, in which a person's recollection of a witnessed event is altered after exposure to misinformation about the event. The neural basis of this phenomenon, however, remains unknown. The authors used fMRI to investigate encoding processes during the viewing of an event and…

  10. On the adaptive function of children's and adults’ false memories

    Science.gov (United States)

    Howe, Mark L.; Wilkinson, Samantha; Garner, Sarah R.; Ball, Linden J.

    2016-01-01

    ABSTRACT Recent research has shown that memory illusions can successfully prime both children's and adults' performance on complex, insight-based problems (compound remote associates tasks or CRATs). The current research aimed to clarify the locus of these priming effects. Like before, Deese–Roediger–McDermott (DRM) lists were selected to prime subsequent CRATs such that the critical lures were also the solution words to a subset of the CRATs participants attempted to solve. Unique to the present research, recognition memory tests were used and participants were either primed during the list study phase, during the memory test phase, or both. Across two experiments, primed problems were solved more frequently and significantly faster than unprimed problems. Moreover, when participants were primed during the list study phase, subsequent solution times and rates were considerably superior to those produced by those participants who were simply primed at test. Together, these are the first results to show that false-memory priming during encoding facilitates problem-solving in both children and adults. PMID:26230151

  11. Effects of Aging on True and False Memory Formation: An fMRI Study

    Science.gov (United States)

    Dennis, Nancy A.; Kim, Hongkeun; Cabeza, Roberto

    2007-01-01

    Compared to young, older adults are more likely to forget events that occurred in the past as well as remember events that never happened. Previous studies examining false memories and aging have shown that these memories are more likely to occur when new items share perceptual or semantic similarities with those presented during encoding. It is…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  14. Veridical and False Memory for Text: A Multiprocess Analysis

    Science.gov (United States)

    Singer, Murray; Remillard, Gilbert

    2008-01-01

    People report recognizing discourse inferences at rates that approach target acceptance. Brainerd et al. [Brainerd, C. J., Wright, R., Reyna, V. F., & Mojardin, A. H. (2001). "Conjoint recognition and phantom recollection." "Journal of Experimental Psychology: Learning, Memory, and Cognition, 27", 307-329] proposed that…

  15. Is there a positive bias in false recognition? Evidence from confabulating amnesia patients.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    OpenAIRE

    Warren, David E.; 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...

  18. Quantum memories with zero-energy Majorana modes and experimental constraints

    Science.gov (United States)

    Ippoliti, Matteo; Rizzi, Matteo; Giovannetti, Vittorio; Mazza, Leonardo

    2016-06-01

    In this work we address the problem of realizing a reliable quantum memory based on zero-energy Majorana modes in the presence of experimental constraints on the operations aimed at recovering the information. In particular, we characterize the best recovery operation acting only on the zero-energy Majorana modes and the memory fidelity that can be therewith achieved. In order to understand the effect of such restriction, we discuss two examples of noise models acting on the topological system and compare the amount of information that can be recovered by accessing either the whole system, or the zero modes only, with particular attention to the scaling with the size of the system and the energy gap. We explicitly discuss the case of a thermal bosonic environment inducing a parity-preserving Markovian dynamics in which the memory fidelity achievable via a read-out of the zero modes decays exponentially in time, independent from system size. We argue, however, that even in the presence of said experimental limitations, the Hamiltonian gap is still beneficial to the storage of information.

  19. Can Maltreated Children Inhibit True and False Memories for Emotional Information?

    Science.gov (United States)

    Howe, Mark L.; Toth, Sheree L.; Cicchetti, Dante

    2011-01-01

    The authors examined 284 maltreated and nonmaltreated children's (6- to 12-year-olds) ability to inhibit true and false memories for neutral and emotional information using the Deese/Roediger-McDermott (DRM) paradigm. Children studied either emotional or neutral DRM lists in a control condition or were given directed-remembering or…

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

    Science.gov (United States)

    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.

  1. Attention to Global Gist Processing Eliminates Age Effects in False Memories

    Science.gov (United States)

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

    2008-01-01

    Counterintuitive age increases have been reported for the Deese-Roediger-McDermott (DRM) false memory illusion. The current theoretical explanation of this effect assumes that it is due to age increases in spontaneous interconnection of DRM list words' meanings. To test this explanation, 11-year-olds and young adults studied DRM lists under…

  2. Experimental and numerical investigations of shape memory alloy helical springs

    International Nuclear Information System (INIS)

    Aguiar, Ricardo A A; Pacheco, Pedro M C L; Savi, Marcelo A

    2010-01-01

    Shape memory alloys (SMAs) belong to the class of smart materials and have been used in numerous applications. Solid phase transformations induced either by stress or temperature are behind the remarkable properties of SMAs that motivate the concept of innovative smart actuators for different purposes. The SMA element used in these actuators can assume different forms and a spring is an element usually employed for this aim. This contribution deals with the modeling, simulation and experimental analysis of SMA helical springs. Basically, a one-dimensional constitutive model is assumed to describe the SMA thermomechanical shear behavior and, afterwards, helical springs are modeled by considering a classical approach for linear-elastic springs. A numerical method based on the operator split technique is developed. SMA helical spring thermomechanical behavior is investigated through experimental tests performed with different thermomechanical loadings. Shape memory and pseudoelastic effects are treated. Numerical simulations show that the model results are in close agreement with those obtained by experimental tests, revealing that the proposed model captures the general thermomechanical behavior of SMA springs

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

    Science.gov (United States)

    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.…

  4. Transformation-Induced Creep and Creep Recovery of Shape Memory Alloy.

    Science.gov (United States)

    Takeda, Kohei; Tobushi, Hisaaki; Pieczyska, Elzbieta A

    2012-05-22

    If the shape memory alloy is subjected to the subloop loading under the stress-controlled condition, creep and creep recovery can appear based on the martensitic transformation. In the design of shape memory alloy elements, these deformation properties are important since the deflection of shape memory alloy elements can change under constant stress. The conditions for the progress of the martensitic transformation are discussed based on the kinetics of the martensitic transformation for the shape memory alloy. During loading under constant stress rate, temperature increases due to the stress-induced martensitic transformation. If stress is held constant during the martensitic transformation stage in the loading process, temperature decreases and the condition for the progress of the martensitic transformation is satisfied, resulting in the transformation-induced creep deformation. If stress is held constant during the reverse transformation stage in the unloading process, creep recovery appears due to the reverse transformation. The details for these thermomechanical properties are investigated experimentally for TiNi shape memory alloy, which is most widely used in practical applications. The volume fraction of the martensitic phase increases in proportion to an increase in creep strain.

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

    Science.gov (United States)

    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.

  6. Sleep and eyewitness memory: Fewer false identifications after sleep when the target is absent from the lineup.

    Science.gov (United States)

    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.

  7. Sleep and eyewitness memory: Fewer false identifications after sleep when the target is absent from the lineup

    Science.gov (United States)

    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

  8. Sleep and eyewitness memory: Fewer false identifications after sleep when the target is absent from the lineup.

    Directory of Open Access Journals (Sweden)

    Michelle E Stepan

    Full Text Available 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.

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

    Science.gov (United States)

    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…

  10. Analyzing False Memories in Children with Associative Lists Specific for Their Age

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  12. "That never happened": adults' discernment of children's true and false memory reports.

    Science.gov (United States)

    Block, Stephanie D; Shestowsky, Donna; Segovia, Daisy A; Goodman, Gail S; Schaaf, Jennifer M; Alexander, Kristen Weede

    2012-10-01

    Adults' evaluations of children's reports can determine whether legal proceedings are undertaken and whether they ultimately lead to justice. The current study involved 92 undergraduates and 35 laypersons who viewed and evaluated videotaped interviews of 3- and 5-year-olds providing true or false memory reports. The children's reports fell into the following categories based on a 2 (event type: true vs. false) × 2 (child report: assent vs. denial) factorial design: accurate reports, false reports, accurate denials, and false denials. Results revealed that adults were generally better able to correctly judge accurate reports, accurate denials, and false reports compared with false denials: For false denials, adults were, on average, "confident" that the event had not occurred, even though the event had in fact been experienced. Participant age predicted performance. These findings underscore the greater difficulty adults have in evaluating young children's false denials compared with other types of reports. Implications for law-related situations in which adults are called upon to evaluate children's statements are discussed. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  13. The almost unanimous false memory of the first World Trade Center impact

    DEFF Research Database (Denmark)

    Hansen, Tia

    2005-01-01

    Although footage of the first plane's crash into World Trade Center did not become publicly available until later, the memory of having seen it on September 11, 2001, seem as pervasive as it is obviously false. In the scientific literature, this error has already been documented in several American...

  14. Explicit episodic memory for sensory-discriminative components of capsaicin-induced pain: immediate and delayed ratings.

    Science.gov (United States)

    Jantsch, H H F; Gawlitza, M; Geber, C; Baumgärtner, U; Krämer, H H; Magerl, W; Treede, R D; Birklein, F

    2009-05-01

    Pain memory is thought to affect future pain sensitivity and thus contribute to clinical pain conditions. Systematic investigations of the human capacity to remember sensory features of experimental pain are sparse. In order to address long-term pain memory, nine healthy male volunteers received intradermal injections of three doses of capsaicin (0.05, 1 and 20 microg, separated by 15 min breaks), each given three times in a balanced design across three sessions at one week intervals. Pain rating was performed using a computerized visual analogue scale (0-100) digitized at 1/s, either immediately online or one hour or one day after injection. Subjects also recalled their pains one week later. Capsaicin injection reliably induced a dose-dependent flare (pmemory traces. These results indicate a reliable memory for magnitude and duration of experimentally induced pain. The data further suggest that the consolidation of this memory is an important interim stage, and may take up to one day.

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

    Science.gov (United States)

    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…

  16. Hemispheric Asymmetries in Semantic Processing: Evidence from False Memories for Ambiguous Words

    Science.gov (United States)

    Faust, Miriam; Ben-Artzi, Elisheva; Harel, Itay

    2008-01-01

    Previous research suggests that the left hemisphere (LH) focuses on strongly related word meanings; the right hemisphere (RH) may contribute uniquely to the processing of lexical ambiguity by activating and maintaining a wide range of meanings, including subordinate meanings. The present study used the word-lists false memory paradigm [Roediger,…

  17. Over-Distribution in Source Memory

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  20. The robustness of false memory for emotional pictures.

    Science.gov (United States)

    Bessette-Symons, Brandy A

    2018-02-01

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

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

    Science.gov (United States)

    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…

  2. Attention Cueing and Activity Equally Reduce False Alarm Rate in Visual-Auditory Associative Learning through Improving Memory.

    Science.gov (United States)

    Nikouei Mahani, Mohammad-Ali; Haghgoo, Hojjat Allah; Azizi, Solmaz; Nili Ahmadabadi, Majid

    2016-01-01

    In our daily life, we continually exploit already learned multisensory associations and form new ones when facing novel situations. Improving our associative learning results in higher cognitive capabilities. We experimentally and computationally studied the learning performance of healthy subjects in a visual-auditory sensory associative learning task across active learning, attention cueing learning, and passive learning modes. According to our results, the learning mode had no significant effect on learning association of congruent pairs. In addition, subjects' performance in learning congruent samples was not correlated with their vigilance score. Nevertheless, vigilance score was significantly correlated with the learning performance of the non-congruent pairs. Moreover, in the last block of the passive learning mode, subjects significantly made more mistakes in taking non-congruent pairs as associated and consciously reported lower confidence. These results indicate that attention and activity equally enhanced visual-auditory associative learning for non-congruent pairs, while false alarm rate in the passive learning mode did not decrease after the second block. We investigated the cause of higher false alarm rate in the passive learning mode by using a computational model, composed of a reinforcement learning module and a memory-decay module. The results suggest that the higher rate of memory decay is the source of making more mistakes and reporting lower confidence in non-congruent pairs in the passive learning mode.

  3. The effect of long term administration of ascorbic acid on the learning and memory deficits induced by diabetes in rat

    Directory of Open Access Journals (Sweden)

    Parisa Hasanein

    2010-04-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Ascorbic acid improves cognitive impairments in several experimental models. Diabetes causes learning and memory deficits. In this study we hypothesized that chronic treatment with ascorbic acid (100mg/kg, p.o would affect on the passive avoidance learning (PAL and memory in control and streptozocin-induced diabetic rats."n"nMethods: Diabetes was induced by a single i.p. injection of STZ (60mg/kg. The rats were considered diabetic if plasma glucose levels exceeded 250mg/dl on three days after STZ injection. Treatment was begun at the onset of hyperglycemia. PAL was assessed 30 days later. Retention test was done 24 h after training. At the end, animals were weighted and blood samples were drawn for plasma glucose measurement."n"nResults: Diabetes caused impairment in acquisition and retrieval processes of PAL and memory in rats. Ascorbic acid treatment improved learning and memory in control rats and reversed learning and memory deficits in diabetic rats. Ascorbic acid administration also improved the body weight loss and hyperglycemia of diabetics. Hypoglycemic and antioxidant properties of the vitamin may be involved in the memory improving effects of such treatment."n"nConclusion: These results show that

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

    Science.gov (United States)

    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.

  5. Lithium prevents REM sleep deprivation-induced impairments on memory consolidation.

    Science.gov (United States)

    Ota, Simone M; Moreira, Karin Di Monteiro; Suchecki, Deborah; Oliveira, Maria Gabriela M; Tiba, Paula A

    2013-11-01

    Pre-training rapid eye movement sleep (REMS) deprivation affects memory acquisition and/or consolidation. It also produces major REMS rebound at the cost of waking and slow wave sleep (SWS). Given that both SWS and REMS appear to be important for memory processes, REMS rebound after training may disrupt the organization of sleep cycles, i.e., excessive amount of REMS and/or little SWS after training could be harmful for memory formation. To examine whether lithium, a drug known to increase SWS and reduce REMS, could prevent the memory impairment induced by pre-training sleep deprivation. Animals were divided in 2 groups: cage control (CC) and REMS-deprived (REMSDep), and then subdivided into 4 subgroups, treated either with vehicle or 1 of 3 doses of lithium (50, 100, and 150 mg/kg) 2 h before training on the multiple trial inhibitory avoidance task. Animals were tested 48 h later to make sure that the drug had been already metabolized and eliminated. Another set of animals was implanted with electrodes and submitted to the same experimental protocol for assessment of drug-induced sleep-wake changes. Wistar male rats weighing 300-400 g. Sleep deprived rats required more trials to learn the task and still showed a performance deficit during test, except from those treated with 150 mg/kg of lithium, which also reduced the time spent in REM sleep during sleep recovery. Lithium reduced rapid eye movement sleep and prevented memory impairment induced by sleep deprivation. These results indicate that these phenomena may be related, but cause-effect relationship cannot be ascertained.

  6. Understanding Developmental Reversals in False Memory: Reply to Ghetti (2008) and Howe (2008)

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  8. Retrieval monitoring is influenced by information value: the interplay between importance and confidence on false memory.

    Science.gov (United States)

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

    2015-10-01

    The perceived value of information can influence one's motivation to successfully remember that information. This study investigated how information value can affect memory search and evaluation processes (i.e., retrieval monitoring). In Experiment 1, participants studied unrelated words associated with low, medium, or high values. Subsequent memory tests required participants to selectively monitor retrieval for different values. False memory effects were smaller when searching memory for high-value than low-value words, suggesting that people more effectively monitored more important information. In Experiment 2, participants studied semantically-related words, and the need for retrieval monitoring was reduced at test by using inclusion instructions (i.e., endorsement of any word related to the studied words) compared with standard instructions. Inclusion instructions led to increases in false recognition for low-value, but not for high-value words, suggesting that under standard-instruction conditions retrieval monitoring was less likely to occur for important information. Experiment 3 showed that words retrieved with lower confidence were associated with more effective retrieval monitoring, suggesting that the quality of the retrieved memory influenced the degree and effectiveness of monitoring processes. Ironically, unless encouraged to do so, people were less likely to carefully monitor important information, even though people want to remember important memories most accurately. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Interaction of Induced Anxiety and Verbal Working Memory: Influence of Trait Anxiety

    Science.gov (United States)

    Patel, Nilam; Stoodley, Catherine; Pine, Daniel S.; Grillon, Christian; Ernst, Monique

    2017-01-01

    This study examines the influence of trait anxiety on working memory (WM) in safety and threat. Interactions between experimentally induced anxiety and WM performance (on different cognitive loads) have been reported in healthy, nonanxious subjects. Differences in trait anxiety may moderate these interactions. Accordingly, these interactions may…

  10. Maintenance of youth-like processing protects against false memory in later adulthood.

    Science.gov (United States)

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

    2015-02-01

    Normal cognitive aging compromises the ability to form and retrieve associations among features of a memory episode. One indicator of this age-related deficit is older adults' difficulty in detecting and correctly rejecting new associations of familiar items. Comparing 28 younger and 30 older adults on a continuous recognition task with word pairs, we found that older adults whose activation patterns deviate less from the average pattern of younger adults while detecting repaired associations show the following: (1) higher overall memory and fewer false recognitions; (2) stronger functional connectivity of prefrontal regions with middle temporal and parahippocampal gyrus; and (3) higher recall and strategic categorical clustering in an independently assessed free recall task. Deviations from the average young-adult network reflected underactivation of frontoparietal regions instead of overactivation of regions not activated by younger adults. We conclude that maintenance of youth-like task-relevant activation patterns is critical for preserving memory functions in later adulthood. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Why Distinctive Information Reduces False Memories: Evidence for Both Impoverished Relational-Encoding and Distinctiveness Heuristic Accounts

    Science.gov (United States)

    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…

  12. Cordyceps militaris extract attenuates D-galactose-induced memory impairment in mice.

    Science.gov (United States)

    Li, Zaixin; Zhang, Zhi; Zhang, Jinshan; Jia, Jing; Ding, Jie; Luo, Rongzhen; Liu, Zhangqin

    2012-12-01

    Memory impairment is one of main clinical symptoms of brain senescence. To address the effects of Cordyceps militaris Link extract (CE) on memory impairment, a D-galactose (D-Gal)-induced aging mouse model was employed. Mice injected with D-Gal showed a significant learning and memory impairment that was rescued by CE treatment. The mechanism was further investigated by analyzing the protein level and activity of oxidant and antioxidant molecules, including malondialdehyde (MDA), monoamine oxidase (MAO), total super-oxide dismutase (T-SOD), total antioxidant capacity (T-AOC), glutathione (GSH), and glutathione peroxidase (GSH-px), which played critical roles in the development of brain senescence. The results showed that CE treatment resulted in a significant decrease in the oxidative activity of MAO and the level of MDA, and significantly increased the antioxidant activities of T-SOD and T-AOC in the cerebral cortices. Moreover, the level of GSH and the activity of antioxidant enzymes GSH-px in serum were significantly upregulated after CE treatment. Taken together, our results suggest that Cordyceps militaris extract could ameliorate experimental memory impairment in mice with D-Gal-induced aging through its potent antioxidant activities.

  13. Age Differences in the Contribution of Recollection and Familiarity to False-Memory Formation: A New Paradigm to Examine Developmental Reversals

    Science.gov (United States)

    Lyons, Kristen E.; Ghetti, Simona; Cornoldi, Cesare

    2010-01-01

    Using a new method for studying the development of false-memory formation, we examined developmental differences in the rates at which 6-, 7-, 9-, 10-, and 18-year-olds made two types of memory errors: backward causal-inference errors (i.e. falsely remembering having viewed the non-viewed cause of a previously viewed effect), and gap-filling…

  14. Disorder-induced microscopic magnetic memory

    International Nuclear Information System (INIS)

    Pierce, M.S.; Buechler, C.R.; Sorensen, L.B.; Turner, J.J.; Kevan, S.D.; Jagla, E.A.; Deutsch, J.M.; Mai, T.; Narayan, O.; Davies, J.E.; Liu, K.; Dunn, J. Hunter; Chesnel, K.M.; Kortright, J.B.; Hellwig, O.; Fullerton, E.E.

    2005-01-01

    Using coherent x-ray speckle metrology, we have measured the influence of disorder on major loop return point memory (RPM) and complementary point memory (CPM) for a series of perpendicular anisotropy Co/Pt multilayer films. In the low disorder limit, the domain structures show no memory with field cycling - no RPM and no CPM. With increasing disorder, we observe the onset and the saturation of both the RPM and the CPM. These results provide the first direct ensemble-sensitive experimental study of the effects of varying disorder on microscopic magnetic memory and are compared against the predictions of existing theories

  15. The emotion-induced memory trade-off: more than an effect of overt attention?

    Science.gov (United States)

    Steinmetz, Katherine R Mickley; Kensinger, Elizabeth A

    2013-01-01

    Although it has been suggested that many effects of emotion on memory are attributable to attention, in the present study we addressed the hypothesis that such effects may relate to a number of different factors during encoding or postencoding. One way to look at the effects of emotion on memory is by examining the emotion-induced memory trade-off, whereby enhanced memory for emotional items often comes at the cost of memory for surrounding background information. We present evidence that this trade-off cannot be explained solely by overt attention (measured via eyetracking) directed to the emotional items during encoding. Participants did not devote more overt attention to emotional than to neutral items when those items were selectively remembered (at the expense of their backgrounds). Only when participants were asked to answer true/false questions about the items and the backgrounds--a manipulation designed to affect both overt attention and poststimulus elaboration--was there a reduction in selective emotional item memory due to an increase in background memory. These results indicate that the allocation of overt visual attention during encoding is not sufficient to predict the occurrence of selective item memory for emotional items.

  16. The Role of Context in Producing Item Interactions and False Memories

    Science.gov (United States)

    Tehan, Gerald; Humphreys, Michael S.; Tolan, Georgina Anne; Pitcher, Cameron

    2004-01-01

    Cued recall with an extralist cue poses a challenge for contemporary memory theory in that there is a need to explain how episodic and semantic information are combined. A parallel activation and intersection approach proposes one such means by assuming that an experimental cue will elicit its preexisting semantic network and a context cue will…

  17. The Repercussion of the False Memories Syndrome in the Eyewitness Testimony: an Analysis of Decisions from the Rio Grande do Sul State Court

    Directory of Open Access Journals (Sweden)

    Flaviane Baldasso

    2018-03-01

    Full Text Available False memories are distortions of memory that can impact decisively on the evaluation of a criminal event of interest to the criminal system. Despite the growing interest in the subject, few empirical works have explored the practical consequences of the phenomenon. Along with, the question is if it is possible to measure the repercussion for our criminal proceedings, as well if the theses concerning false memories have been accepted by the Judiciary and in which cases. The present article intends to analyze the repercussion of the phenomenon of false memories, in terms of testimonial evidence, from 437 judgments of the Court of Justice of Rio Grande do Sul. Using the content analysis methodology of Lawrence Bardin, we explored the types of crimes in which the false memories argument has been used, if the hypothesis of this distortion has sensitized the judges, as well as if the analyzes of the judges have been supported in the bibliographical production on the psychology of the testimony. From the numbers raised, it was possible to perceive a considerable increase in the invocation of the argument of the False Memories, but this has not been reversed in the promotion of freedom in the scope of the gaucho penal process.

  18. The effects of initial testing on false recall and false recognition in the social contagion of memory paradigm.

    Science.gov (United States)

    Huff, Mark J; Davis, Sara D; Meade, Michelle L

    2013-08-01

    In three experiments, participants studied photographs of common household scenes. Following study, participants completed a category-cued recall test without feedback (Exps. 1 and 3), a category-cued recall test with feedback (Exp. 2), or a filler task (no-test condition). Participants then viewed recall tests from fictitious previous participants that contained erroneous items presented either one or four times, and then completed final recall and source recognition tests. The participants in all conditions reported incorrect items during final testing (a social contagion effect), and across experiments, initial testing had no impact on false recall of erroneous items. However, on the final source-monitoring recognition test, initial testing had a protective effect against false source recognition: Participants who were initially tested with and without feedback on category-cued initial tests attributed fewer incorrect items to the original event on the final source-monitoring recognition test than did participants who were not initially tested. These data demonstrate that initial testing may protect individuals' memories from erroneous suggestions.

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

    Science.gov (United States)

    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.

  20. A memory module for experimental data handling

    Science.gov (United States)

    De Blois, J.

    1985-02-01

    A compact CAMAC memory module for experimental data handling was developed to eliminate the need of direct memory access in computer controlled measurements. When using autonomous controllers it also makes measurements more independent of the program and enlarges the available space for programs in the memory of the micro-computer. The memory module has three modes of operation: an increment-, a list- and a fifo mode. This is achieved by connecting the main parts, being: the memory (MEM), the fifo buffer (FIFO), the address buffer (BUF), two counters (AUX and ADDR) and a readout register (ROR), by an internal 24-bit databus. The time needed for databus operations is 1 μs, for measuring cycles as well as for CAMAC cycles. The FIFO provides temporary data storage during CAMAC cycles and separates the memory part from the application part. The memory is variable from 1 to 64K (24 bits) by using different types of memory chips. The application part, which forms 1/3 of the module, will be specially designed for each application and is added to the memory chian internal connector. The memory unit will be used in Mössbauer experiments and in thermal neutron scattering experiments.

  1. Retrieval-Induced Inhibition in Short-Term Memory.

    Science.gov (United States)

    Kang, Min-Suk; Choi, Joongrul

    2015-07-01

    We used a visual illusion called motion repulsion as a model system for investigating competition between two mental representations. Subjects were asked to remember two random-dot-motion displays presented in sequence and then to report the motion directions for each. Remembered motion directions were shifted away from the actual motion directions, an effect similar to the motion repulsion observed during perception. More important, the item retrieved second showed greater repulsion than the item retrieved first. This suggests that earlier retrieval exerted greater inhibition on the other item being held in short-term memory. This retrieval-induced motion repulsion could be explained neither by reduced cognitive resources for maintaining short-term memory nor by continued inhibition between short-term memory representations. These results indicate that retrieval of memory representations inhibits other representations in short-term memory. We discuss mechanisms of retrieval-induced inhibition and their implications for the structure of memory. © The Author(s) 2015.

  2. On the Susceptibility of Adaptive Memory to False Memory Illusions

    Science.gov (United States)

    Howe, Mark L.; Derbish, Mary H.

    2010-01-01

    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…

  3. Recognition-induced forgetting of faces in visual long-term memory.

    Science.gov (United States)

    Rugo, Kelsi F; Tamler, Kendall N; Woodman, Geoffrey F; Maxcey, Ashleigh M

    2017-10-01

    Despite more than a century of evidence that long-term memory for pictures and words are different, much of what we know about memory comes from studies using words. Recent research examining visual long-term memory has demonstrated that recognizing an object induces the forgetting of objects from the same category. This recognition-induced forgetting has been shown with a variety of everyday objects. However, unlike everyday objects, faces are objects of expertise. As a result, faces may be immune to recognition-induced forgetting. However, despite excellent memory for such stimuli, we found that faces were susceptible to recognition-induced forgetting. Our findings have implications for how models of human memory account for recognition-induced forgetting as well as represent objects of expertise and consequences for eyewitness testimony and the justice system.

  4. Do emotional stimuli enhance or impede recall relative to neutral stimuli? An investigation of two "false memory" tasks.

    Science.gov (United States)

    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.

  5. A memory module for experimental data handling

    International Nuclear Information System (INIS)

    Blois, J. de

    1985-01-01

    A compact CAMAC memory module for experimental data handling was developed to eliminate the need of direct memory access in computer controlled measurements. When using autonomous controllers it also makes measurements more independent of the program and enlarges the available space for programs in the memory of the micro-computer. The memory module has three modes of operation: an increment-, a list- and a fifo mode. This is achieved by connecting the main parts, being: the memory (MEM), the fifo buffer (FIFO), the address buffer (BUF), two counters (AUX and ADDR) and a readout register (ROR), by an internal 24-bit databus. The time needed for databus operations is 1 μs, for measuring cycles as well as for CAMAC cycles. The FIFO provides temporary data storage during CAMAC cycles and separates the memory part from the application part. The memory is variable from 1 to 64K (24 bits) by using different types of memory chips. The application part, which forms 1/3 of the module, will be specially designed for each application and is added to the memory by an internal connector. The memory unit will be used in Moessbauer experiments and in thermal neutron scattering experiments. (orig.)

  6. Modelling and experimental investigation of geometrically graded NiTi shape memory alloys

    International Nuclear Information System (INIS)

    Shariat, Bashir S; Liu, Yinong; Rio, Gerard

    2013-01-01

    To improve actuation controllability of a NiTi shape memory alloy component in applications, it is desirable to create a wide stress window for the stress-induced martensitic transformation in the alloy. One approach is to create functionally graded NiTi with a geometric gradient in the actuation direction. This geometric gradient leads to transformation load and displacement gradients in the structure. This paper reports a study of the pseudoelastic behaviour of geometrically graded NiTi by means of mechanical model analysis and experimentation using three types of sample geometry. Closed-form solutions are obtained for nominal stress–strain variation of such components under cyclic tensile loading and the predictions are validated with experimental data. The geometrically graded NiTi samples exhibit a distinctive positive stress gradient for the stress-induced martensitic transformation and the slope of the stress gradient can be adjusted by sample geometry design. (paper)

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

    Science.gov (United States)

    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.

  8. Experimental study and theoretical simulation of the cross hardening effect in shape memory alloys

    Science.gov (United States)

    Movchan, A. A.; Sil'chenko, A. L.; Kazarina, S. A.

    2017-10-01

    The shapes and the relative position of martensitic inelasticity and forward transformation diagrams are experimentally studied. The strain dependences of the stress in loading under martensitic inelasticity conditions after an experiment on the accumulation of the forward transformation-induced strain at a constant or variable stress are investigated on titanium nickelide samples. It is found that the hardening of the martensite part of the representative volume of a shape memory alloy (titanium nickelide) after forward transformation under a nonmonotonically changing stress can be nonuniform. The cross hardening phenomenon is theoretically described in terms of the model of nonlinear deformation of a shape memory alloy during phase and structural transformations.

  9. Comparative study of false memory in dementia with Lewy bodies and Alzheimer's disease.

    Science.gov (United States)

    Phillipps, Clélie; Kemp, Jennifer; Jacob, Christel; Veronneau, Alyssa; Albasser, Timothée; Philippi, Nathalie; Cretin, Benjamin; Bernard, Frédéric; Blanc, Frédéric

    2016-09-01

    The production of false memories (FMs) is a normal phenomenon, which can be affected in neurodegenerative diseases such as Alzheimer's disease (AD). Only few studies investigated FMs in patients with dementia with Lewy bodies (DLB). The aim of our preliminary study was to assess FMs in patients with DLB and to identify the underlying cognitive deficits influencing the production of FMs in DLB and AD. Ten AD patients and nine DLB patients performed a memory task (free recall and recognition) coupling two paradigms, namely the DRM (Deese-Roediger-McDermott) paradigm, promoting the production of FMs and the "Remember/Know" (R/K) paradigm, allowing to investigate the phenomenological experience during the recollection of a memory. A standard cognitive evaluation of memory, executive and instrumental functions completed the assessment. No FM was found in the DLB group during free recall, while the number of FMs was substantially identical in both groups during recognition. However, FMs differed from the phenomenological experience, with more K responses in DLB patients and more R responses in AD patients. None of the tests of the standard neuropsychological evaluation did correlate with measures of interest of FMs. In AD patients, the R responses associated with FMs reflect an alteration of the source memory. In DLB patients, the critical item lead to a sense of familiarity, without recollection of the circumstances in which the item was encoded, hence the K responses. This indicates a preservation of their source memory. Contrary to expectations, the type of FMs in both groups was not correlated to their cognitive profile. Hence, cognitive processes underlying the FMs appear to be different in AD and the LBD, but FMs seem independent of memory and executive abilities in these diseases.

  10. Effects of scallop shell extract on scopolamine-induced memory impairment and MK801-induced locomotor activity.

    Science.gov (United States)

    Hasegawa, Yasushi; Inoue, Tatsuro; Kawaminami, Satoshi; Fujita, Miho

    2016-07-01

    To evaluate the neuroprotective effects of the organic components of scallop shells (scallop shell extract) on memory impairment and locomotor activity induced by scopolamine or 5-methyl-10,11-dihydro-5H-dibenzo (a,d) cyclohepten-5,10-imine (MK801). Effect of the scallop shell extract on memory impairment and locomotor activity was investigated using the Y-maze test, the Morris water maze test, and the open field test. Scallop shell extract significantly reduced scopolamine-induced short-term memory impairment and partially reduced scopolamine-induced spatial memory impairment in the Morris water maze test. Scallop shell extract suppressed scopolamine-induced elevation of acetylcholine esterase activity in the cerebral cortex. Treatment with scallop shell extract reversed the increase in locomotor activity induced by scopolamine. Scallop shell extract also suppressed the increase in locomotor activity induced by MK801. Our results provide initial evidence that scallop shell extract reduces scopolamine-induced memory impairment and suppresses MK-801-induced hyperlocomotion. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

  11. 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.

    Science.gov (United States)

    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.

  12. Computer Game Play Reduces Intrusive Memories of Experimental Trauma via Reconsolidation-Update Mechanisms.

    Science.gov (United States)

    James, Ella L; Bonsall, Michael B; Hoppitt, Laura; Tunbridge, Elizabeth M; Geddes, John R; Milton, Amy L; Holmes, Emily A

    2015-08-01

    Memory of a traumatic event becomes consolidated within hours. Intrusive memories can then flash back repeatedly into the mind's eye and cause distress. We investigated whether reconsolidation-the process during which memories become malleable when recalled-can be blocked using a cognitive task and whether such an approach can reduce these unbidden intrusions. We predicted that reconsolidation of a reactivated visual memory of experimental trauma could be disrupted by engaging in a visuospatial task that would compete for visual working memory resources. We showed that intrusive memories were virtually abolished by playing the computer game Tetris following a memory-reactivation task 24 hr after initial exposure to experimental trauma. Furthermore, both memory reactivation and playing Tetris were required to reduce subsequent intrusions (Experiment 2), consistent with reconsolidation-update mechanisms. A simple, noninvasive cognitive-task procedure administered after emotional memory has already consolidated (i.e., > 24 hours after exposure to experimental trauma) may prevent the recurrence of intrusive memories of those emotional events. © The Author(s) 2015.

  13. Memory plays tricks on me: perceptual bias induced by memory reactivated size in Ebbinghaus illusion.

    Science.gov (United States)

    Rey, Amandine E; Vallet, Guillaume T; Riou, Benoit; Lesourd, Mathieu; Versace, Rémy

    2015-10-01

    The relationship between perceptual and memory processing is at the core of cognition. Growing evidence suggests reciprocal influences between them so that memory features should lead to an actual perceptual bias. In the present study, we investigate the reciprocal influence of perceptual and memory processing by further adapting the Ebbinghaus illusion and tested it in a psychophysical design. In a 2AFC (two-alternative forced choice) paradigm, the perceptual bias in the Ebbinghaus illusion was induced by a physical size (Experiment 1) or a memory reactivated size of the inducers (Experiment 2, the size was reactivated thanks to a color-size association). One test disk was presented on the left of the screen and was surrounded by six inducers with a large or small (perceptual or reactivated) size. The test disk varied in size and participants were asked to indicate whether this test disk was smaller or larger than a reference disk presented on the right of the screen (the reference disk was invariant in size). Participants' responses were influenced by the size of the inducers for the perceptual and the reactivated size of the inducers. These results provide new evidence for the influence of memory on perception in a psychophysics paradigm. Published by Elsevier B.V.

  14. Effects of some dopamine antagonists on spatial memory performance in rats--experimental research.

    Science.gov (United States)

    Rusu, Gabriela; Popa, Gratiela; Ochiuz, Lacramioara; Nechifor, M; Tartau, Liliana

    2014-01-01

    Dopamine is a neurotransmitter with an important role in forming long-lasting memories for some time, especially in episodic memory. Literature data show that dopamine receptor stimulation may be detrimental to spatial working memory functions in lab animals. (R)-(+)-7-Chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride derivative--SCH-23390 is a synthetic compound that acts as a selective, high-affinity antagonist of D1 receptors. Experimental studies suggest that SCH 23390 may prevent the spatial working memory disturbances induced by the active substances of marijuana. Melperone is an atypic antipsychotic drug presenting also dopaminergic D2 and 5-HT2A receptor antagonistic activity. This neuroleptic agent is used in the treatment of some types of schizophrenia. Experimental research on the effects of two dopamine receptor antagonists on spatial memory performance in rats. The experiment was carried out in white Wistar rats (200-250g), divided into 3 groups of 7 animals each, treated intraperitoneally with the same volume of solution for 14 days, as follows: Group I (Control): saline solution 0.1 ml/10g kbw; Group II (coded SCH): SCH-23390 0.3 mg/kbw; Group III (coded MLP): melperone 2 mg/kbw. The dopaminergic agent spatial memory performance was assessed by recording spontaneous alternation behavior in a single session in Y-maze. Each animal was placed at the end of one arm and allowed to move freely through the maze during an 8 min session. Alternation was defined as a consecutive entry in three different arms. The alternation percentage was computed with the following formula: number of alternations divided by total number of arm visits minus 2. Data were presented as +/- standard deviation and significance was tested by SPSS Statistics for Windows version 13.0 and ANOVA method. P-values less than 0.05 were considered statistically significant compared to those in the control group. Experimental researches were carried out in

  15. Paradoxical false memory for objects after brain damage.

    Science.gov (United States)

    McTighe, Stephanie M; Cowell, Rosemary A; Winters, Boyer D; Bussey, Timothy J; Saksida, Lisa M

    2010-12-03

    Poor memory after brain damage is usually considered to be a result of information being lost or rendered inaccessible. It is assumed that such memory impairment must be due to the incorrect interpretation of previously encountered information as being novel. In object recognition memory experiments with rats, we found that memory impairment can take the opposite form: a tendency to treat novel experiences as familiar. This impairment could be rescued with the use of a visual-restriction procedure that reduces interference. Such a pattern of data can be explained in terms of a recent representational-hierarchical view of cognition.

  16. Effect of Cistanche Desertica Polysaccharides on Learning and Memory Functions and Ultrastructure of Cerebral Neurons in Experimental Aging Mice

    Institute of Scientific and Technical Information of China (English)

    孙云; 邓杨梅; 王德俊; 沈春锋; 刘晓梅; 张洪泉

    2001-01-01

    To observe the effects of Cistanche desertica polysaccharides (CDP) on the learning and memory functions and cerebral ultrastructure in experimental aging mice. Methods: CDP was administrated intragastrically 50 or 100 mg/kg per day for 64 successive days to experimental aging model mice induced by D-galactose, then the learning and memory functions of mice were estimated by step-down test and Y-maze test; organelles of brain tissue and cerebral ultrastructure were observed by transmission electron microscope and physical strength was determined by swimming test. Results: CDP could obviously enhance the learning and memory functions (P<0.01) and prolong the swimming time (P<0.05), decrease the number of lipofuscin and slow down the degeneration of mitochondria in neurons(P<0.05), and improve the degeneration of cerebral ultra-structure in aging mice. Conclusion: CDP could improve the impaired physiological function and alleviate cerebral morphological change in experimental aging mice.

  17. Need for Cognition and False Memory: Can One's Natural Processing Style Be Manipulated by External Factors?

    Science.gov (United States)

    Wootan, Samantha S; Leding, Juliana K

    2015-01-01

    The purpose of this experiment was to provide an enhanced understanding of need for cognition (NFC) and its influence on one's memory accuracy. People who are high in NFC tend to put more cognitive effort into their mental processes than their low-NFC counterparts. To determine whether one's natural processing tendencies, as determined by NFC, can be influenced by external factors, manipulations to levels of processing were added. Participants viewed word lists from the Deese-Roediger-McDermott (DRM) paradigm and were instructed to process half of the DRM lists deeply and the other half shallowly. After all the lists were presented, participants completed 3 successive recall tests. The deep processing condition produced higher rates of false memories for both NFC groups than the shallow processing condition. In addition, the high-NFC group produced higher rates of target recall in both the deep and shallow conditions than the low-NFC group. However, the high-NFC group also produced higher rates of false recall for the shallowly processed lists. These data indicate that high-NFC people exhibit enhanced target recall for word lists, which may come at the expense of overall accuracy due to the increase of false recall.

  18. Scoliosis correction with shape-memory metal: results of an experimental study.

    Science.gov (United States)

    Wever, D J; Elstrodt, J A; Veldhuizen, A G; v Horn, J R

    2002-04-01

    The biocompatibility and functionality of a new scoliosis correction device, based on the properties of the shape-memory metal nickel-titanium alloy, were studied. With this device, the shape recovery forces of a shape-memory metal rod are used to achieve a gradual three-dimensional scoliosis correction. In the experimental study the action of the new device was inverted: the device was used to induce a scoliotic curve instead of correcting one. Surgical procedures were performed in six pigs. An originally curved squared rod, in the cold condition, was straightened and fixed to the spine with pedicle screws. Peroperatively, the memory effect of the rod was activated by heating the rod to 50 degrees C by a low-voltage, high-frequency current. After 3 and after 6 months the animals were sacrificed. The first radiographs, obtained immediately after surgery, showed in all animals an induced curve of about 40 degrees Cobb angle - the original curve of the rod. This curve remained constant during the follow-up. The postoperative serum nickel measurements were around the detection limit, and were not significantly higher compared to the preoperative nickel concentration. Macroscopic inspection after 3 and 6 months showed that the device was almost overgrown with newly formed bone. Corrosion and fretting processes were not observed. Histologic examination of the sections of the surrounding tissues and sections of the lung, liver, spleen and kidney showed no evidence of a foreign body response. In view of the initiation of the scoliotic deformation, it is expected that the shape-memory metal based scoliosis correction device also has the capacity to correct a scoliotic curve. Moreover, it is expected that the new device will show good biocompatibility in clinical application. Extensive fatigue testing of the whole system should be performed before clinical trials are initiated.

  19. Developmentally Invariant Dissociations in Children's True and False Memories: Not All Relatedness Is Created Equal

    Science.gov (United States)

    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…

  20. Effects of Different Types of True-False Questions on Memory Awareness and Long-Term Retention

    Science.gov (United States)

    Schaap, Lydia; Verkoeijen, Peter; Schmidt, Henk

    2014-01-01

    This study investigated the effects of two different true-false questions on memory awareness and long-term retention of knowledge. Participants took four subsequent knowledge tests on curriculum learning material that they studied at different retention intervals prior to the start of this study (i.e. prior to the first test). At the first and…

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

    Science.gov (United States)

    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).

  2. Synesthesia and Memory: Color Congruency, Von Restorff, and False Memory Effects

    Science.gov (United States)

    Radvansky, Gabriel A.; Gibson, Bradley S.; McNerney, M. Windy

    2011-01-01

    In the current study, we explored the influence of synesthesia on memory for word lists. We tested 10 grapheme-color synesthetes who reported an experience of color when reading letters or words. We replicated a previous finding that memory is compromised when synesthetic color is incongruent with perceptual color. Beyond this, we found that,…

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

    Science.gov (United States)

    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.

  4. Effects of Danggui-Shaoyao-San on the Influence of Spatial Learning and Memory Induced by Experimental Tooth Movement.

    Science.gov (United States)

    Li, Hong-Shi; Ke, Jie; Zhao, Gui-Zhi; Wu, Li-An; Kou, Jun-Ping; Liu, Hong-Chen

    2015-07-20

    The pain caused by orthodontic treatment has been considered as tough problems in orthodontic practice. There is substantial literature on pain which has exactly effected on learning and memory; orthodontic tooth movement affected the emotional status has been showed positive outcomes. Danggui-Shaoyao-San (DSS) is a Traditional Chinese Medicine prescription that has been used for pain treatment and analgesic effect for orthodontic pain via inhibiting the activations of neuron and glia. We raised the hypothesis that DSS could restore the impaired abilities of spatial learning and memory via regulating neuron or glia expression in the hippocampus. A total of 36 rats were randomly divided into three groups: (1) Sham group (n = 12), rats underwent all the operation procedure except for the placement of orthodontic forces and received saline treatment; (2) experimental tooth movement (ETM) group (n = 12), rats received saline treatment and ETM; (3) DSS + ETM (DETM) group (n = 12), rats received DSS treatment and ETM. All DETM group animals were administered with DSS at a dose of 150 mg/kg. Morris water maze test was evaluated; immunofluorescent histochemistry was used to identify astrocytes activation, and immunofluorescent dendritic spine analysis was used to identify the dendritic spines morphological characteristics expression levels in hippocampus. Maze training sessions during the 5 successive days revealed that ETM significantly deficits in progressive learning in rats, DSS that was given from day 5 prior to ETM enhanced progressive learning. The ETM group rats took longer to cross target quadrant during the probe trial and got less times to cross-platform than DETM group. The spine density in hippocampus in ETM group was significantly decreased compared to the sham group. In addition, thin and mature spine density were decreased too. However, the DSS administration could reverse the dendritic shrinkage and increase the spine density compared to the ETM group

  5. Effects of Danggui-Shaoyao-San on the Influence of Spatial Learning and Memory Induced by Experimental Tooth Movement

    Institute of Scientific and Technical Information of China (English)

    Hong-Shi Li; Jie Ke; Gui-Zhi Zhao; Li-An Wu; Jun-Ping Kou; Hong-Chen Liu

    2015-01-01

    Background:The pain caused by orthodontic treatment has been considered as tough problems in orthodontic practice.There is substantial literature on pain which has exactly effected on learning and memory;orthodontic tooth movement affected the emotional status has been showed positive outcomes.Danggui-Shaoyao-San (DSS) is a Traditional Chinese Medicine prescription that has been used for pain treatment and analgesic effect for orthodontic pain via inhibiting the activations of neuron and glia.We raised the hypothesis that DSS could restore the impaired abilities of spatial learning and memory via regulating neuron or glia expression in the hippocampus.Methods:A total of 36 rats were randomly divided into three groups:(1) Sham group (n =12),rats underwent all the operation procedure except for the placement of orthodontic forces and received saline treatment;(2) experimental tooth movement (ETM) group (n =12),rats received saline treatment and ETM;(3) DSS + ETM (DETM) group (n =12),rats received DSS treatment and ETM.All DETM group animals were administered with DSS at a dose of 150 mg/kg.Morris water maze test was evaluated;immunofluorescent histochemistry was used to identify astrocytes activation,and immunofluorescent dendritic spine analysis was used to identify the dendritic spines morphological characteristics expression levels in hippocampus.Results:Maze training sessions during the 5 successive days revealed that ETM significantly deficits in progressive learning in rats,DSS that was given from day 5 prior to ETM enhanced progressive learning.The ETM group rats took longer to cross target quadrant during the probe trial and got less times to cross-platform than DETM group.The spine density in hippocampus in ETM group was significantly decreased compared to the sham group.In addition,thin and mature spine density were decreased too.However,the DSS administration could reverse the dendritic shrinkage and increase the spine density compared to the ETM group

  6. Sleep disturbance induces neuroinflammation and impairment of learning and memory.

    Science.gov (United States)

    Zhu, Biao; Dong, Yuanlin; Xu, Zhipeng; Gompf, Heinrich S; Ward, Sarah A P; Xue, Zhanggang; Miao, Changhong; Zhang, Yiying; Chamberlin, Nancy L; Xie, Zhongcong

    2012-12-01

    Hospitalized patients can develop cognitive function decline, the mechanisms of which remain largely to be determined. Sleep disturbance often occurs in hospitalized patients, and neuroinflammation can induce learning and memory impairment. We therefore set out to determine whether sleep disturbance can induce neuroinflammation and impairment of learning and memory in rodents. Five to 6-month-old wild-type C57BL/6J male mice were used in the studies. The mice were placed in rocking cages for 24 h, and two rolling balls were present in each cage. The mice were tested for learning and memory function using the Fear Conditioning Test one and 7 days post-sleep disturbance. Neuroinflammation in the mouse brain tissues was also determined. Of the Fear Conditioning studies at one day and 7 days after sleep disturbance, twenty-four hour sleep disturbance decreased freezing time in the context test, which assesses hippocampus-dependent learning and memory; but not the tone test, which assesses hippocampus-independent learning and memory. Sleep disturbance increased pro-inflammatory cytokine IL-6 levels and induced microglia activation in the mouse hippocampus, but not the cortex. These results suggest that sleep disturbance induces neuroinflammation in the mouse hippocampus, and impairs hippocampus-dependent learning and memory in mice. Pending further studies, these findings suggest that sleep disturbance-induced neuroinflammation and impairment of learning and memory may contribute to the development of cognitive function decline in hospitalized patients. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Changes in Tryptophan Catabolite (TRYCAT) Pathway Patterning Are Associated with Mild Impairments in Declarative Memory in Schizophrenia and Deficits in Semantic and Episodic Memory Coupled with Increased False-Memory Creation in Deficit Schizophrenia.

    Science.gov (United States)

    Kanchanatawan, Buranee; Hemrungrojn, Solaphat; Thika, Supaksorn; Sirivichayakul, Sunee; Ruxrungtham, Kiat; Carvalho, André F; Geffard, Michel; Anderson, George; Maes, Michael

    2018-06-01

    Evidence indicates that schizophrenia and in particular negative symptoms and deficit schizophrenia are accompanied by neurocognitive impairments and changes in the patterning of the tryptophan catabolite (TRYCAT) pathway. This cross-sectional study was carried out to examine the associations between cognitive functions (as measured with Consortium to Establish a Registry for Alzheimer's disease (CERAD)) and TRYCAT pathway patterning in patients with (n = 40) and without (n = 40) deficit schizophrenia and normal controls (n = 40). Cognitive measures were assessed with the Verbal Fluency Test (VFT), Boston Naming Test (BNT), Mini-Mental State Examination (MMSE), Word List Memory (WLM), Constructional Praxis, Word List Recall (WLRecall), and Word List Recognition (WLRecognition), while TRYCAT measurements assessed the IgA/IgM responses to noxious TRYCATs, namely quinolinic acid (QA), 3-OH-kynurenine (3HK), picolinic acid (PA), and xanthurenic (XA) acid, and more protective (PRO) TRYCATs, including kynurenic acid (KA) and anthranilic acid (AA). IgA NOX/PRO, IgM KA/3HK, and IgA/IgM NOX/PRO ratios were computed. Schizophrenia was accompanied by lower VFT and WLM, while BNT (dysnomia) and MMSE are significantly lower in multiple- than first-episode schizophrenia. Deficit schizophrenia is strongly associated with worse outcomes on VFT, MMSE, WLM, WLRecall, WLRecognition, and delayed recall savings and increased false memories. Around 40-50% of the variance in negative symptoms' scores was explained by VFT, WLM, WLRecall, and MMSE. Increases in IgA NOX/PRO, IgM KA/3HK, and/or IgA/IgM NOX/PRO ratios were associated with impairments in VFT, BNT, MMSE, WLM, WLRecall, WLRecognition, and false-memory creation. In conclusion, nondeficit schizophrenia is accompanied by mild memory impairments, while disease progression is accompanied by broader cognitive impairments. Deficit schizophrenia and negative symptoms are strongly associated with deficits in working memory, delayed

  8. Histone deacetylase inhibition abolishes stress-induced spatial memory impairment.

    Science.gov (United States)

    Vargas-López, Viviana; Lamprea, Marisol R; Múnera, Alejandro

    2016-10-01

    Acute stress induced before spatial training impairs memory consolidation. Although non-epigenetic underpinning of such effect has been described, the epigenetic mechanisms involved have not yet been studied. Since spatial training and intense stress have opposite effects on histone acetylation balance, it is conceivable that disruption of such balance may underlie acute stress-induced spatial memory consolidation impairment and that inhibiting histone deacetylases prevents such effect. Trichostatin-A (TSA, a histone deacetylase inhibitor) was used to test its effectiveness in preventing stress' deleterious effect on memory. Male Wistar rats were trained in a spatial task in the Barnes maze; 1-h movement restraint was applied to half of them before training. Immediately after training, stressed and non-stressed animals were randomly assigned to receive either TSA (1mg/kg) or vehicle intraperitoneal injection. Twenty-four hours after training, long-term spatial memory was tested; plasma and brain tissue were collected immediately after the memory test to evaluate corticosterone levels and histone H3 acetylation in several brain areas. Stressed animals receiving vehicle displayed memory impairment, increased plasma corticosterone levels and markedly reduced histone H3 acetylation in prelimbic cortex and hippocampus. Such effects did not occur in stressed animals treated with TSA. The aforementioned results support the hypothesis that acute stress induced-memory impairment is related to histone deacetylation. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Histone Deacetylase Inhibition Facilitates Massed Pattern-Induced Synaptic Plasticity and Memory

    Science.gov (United States)

    Pandey, Kiran; Sharma, Kaushik P.; Sharma, Shiv K.

    2015-01-01

    Massed training is less effective for long-term memory formation than the spaced training. The role of acetylation in synaptic plasticity and memory is now well established. However, the role of this important protein modification in synaptic plasticity induced by massed pattern of stimulation or memory induced by massed training is not well…

  10. I Imagine, I Experience, I Like: The False Experience Effect

    OpenAIRE

    Priyali Rajagopal; Nicole Votolato Montgomery

    2011-01-01

    False memories refer to the mistaken belief that an event that did not occur did occur. Much of the research on false memories has focused on the antecedents to and the characteristics of such memories, with little focus on the consequences of false memories. In this research, we show that exposure to an imagery-evoking ad can result in an erroneous belief that an individual has experienced the advertised brand. We also demonstrate that such false experiential beliefs function akin to genuine...

  11. Experimental Effects of Acute Exercise on Iconic Memory, Short-Term Episodic, and Long-Term Episodic Memory

    Directory of Open Access Journals (Sweden)

    Danielle Yanes

    2018-06-01

    Full Text Available The present experiment evaluated the effects of acute exercise on iconic memory and short- and long-term episodic memory. A two-arm, parallel-group randomized experiment was employed (n = 20 per group; Mage = 21 year. The experimental group engaged in an acute bout of moderate-intensity treadmill exercise for 15 min, while the control group engaged in a seated, time-matched computer task. Afterwards, the participants engaged in a paragraph-level episodic memory task (20 min delay and 24 h delay recall as well as an iconic memory task, which involved 10 trials (at various speeds from 100 ms to 800 ms of recalling letters from a 3 × 3 array matrix. For iconic memory, there was a significant main effect for time (F = 42.9, p < 0.001, η2p = 0.53 and a trend towards a group × time interaction (F = 2.90, p = 0.09, η2p = 0.07, but no main effect for group (F = 0.82, p = 0.37, η2p = 0.02. The experimental group had higher episodic memory scores at both the baseline (19.22 vs. 17.20 and follow-up (18.15 vs. 15.77, but these results were not statistically significant. These findings provide some suggestive evidence hinting towards an iconic memory and episodic benefit from acute exercise engagement.

  12. False memories and lexical decision: even twelve primes do not cause long-term semantic priming.

    Science.gov (United States)

    Zeelenberg, René; Pecher, Diane

    2002-03-01

    Semantic priming effects are usually obtained only if the prime is presented shortly before the target stimulus. Recent evidence obtained with the so-called false memory paradigm suggests, however, that in both explicit and implicit memory tasks semantic relations between words can result in long-lasting effects when multiple 'primes' are presented. The aim of the present study was to investigate whether these effects would generalize to lexical decision. In four experiments we showed that even as many as 12 primes do not cause long-term semantic priming. In all experiments, however, a repetition priming effect was obtained. The present results are consistent with a number of other results showing that semantic information plays a minimal role in long-term priming in visual word recognition.

  13. Decoupling Semantic and Associative Information in False Memories: Explorations with Semantically Ambiguous and Unambiguous Critical Lures

    Science.gov (United States)

    Hutchison, K.A.; Balota, D.A.

    2005-01-01

    Veridical and false memory were examined in lists that contained 12 words that all converged onto the same meaning of a critical nonpresented word (e.g., snooze, wake, bedroom, slumber..., for SLEEP) or lists that contained 6 words that converged onto one meaning and 6 words that converged onto a different meaning of a homograph (e.g., stumble,…

  14. Proinflammatory Factors Mediate Paclitaxel-Induced Impairment of Learning and Memory

    Directory of Open Access Journals (Sweden)

    Zhao Li

    2018-01-01

    Full Text Available The chemotherapeutic agent paclitaxel is widely used for cancer treatment. Paclitaxel treatment impairs learning and memory function, a side effect that reduces the quality of life of cancer survivors. However, the neural mechanisms underlying paclitaxel-induced impairment of learning and memory remain unclear. Paclitaxel treatment leads to proinflammatory factor release and neuronal apoptosis. Thus, we hypothesized that paclitaxel impairs learning and memory function through proinflammatory factor-induced neuronal apoptosis. Neuronal apoptosis was assessed by TUNEL assay in the hippocampus. Protein expression levels of tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β in the hippocampus tissue were analyzed by Western blot assay. Spatial learning and memory function were determined by using the Morris water maze (MWM test. Paclitaxel treatment significantly increased the escape latencies and decreased the number of crossing in the MWM test. Furthermore, paclitaxel significantly increased the number of TUNEL-positive neurons in the hippocampus. Also, paclitaxel treatment increased the expression levels of TNF-α and IL-1β in the hippocampus tissue. In addition, the TNF-α synthesis inhibitor thalidomide significantly attenuated the number of paclitaxel-induced TUNEL-positive neurons in the hippocampus and restored the impaired spatial learning and memory function in paclitaxel-treated rats. These data suggest that TNF-α is critically involved in the paclitaxel-induced impairment of learning and memory function.

  15. Beneficial Effects of Gagam-Palmultang on Scopolamine-Induced Memory Deficits in Mice

    Directory of Open Access Journals (Sweden)

    Yu Ri Kim

    2018-01-01

    Full Text Available From text mining of Dongeuibogam, the 7 herbs in Palmultang can be considered effective candidates for memory enhancement. We sought to determine whether Gagam-Palmultang, comprising these 7 herbs, ameliorates scopolamine-induced memory impairment in mice, by focusing on the central cholinergic system and memory-related signaling molecules. Behavioral tests were performed after inducing memory impairment by scopolamine administration. The cholinergic system activity and memory-related molecules were examined in the hippocampus by enzyme-linked immunosorbent, western blot, and immunofluorescence assays. Gagam-Palmultang ameliorated scopolamine-induced memory impairment in the Morris water maze test, producing a significant improvement in the mean time required to find the hidden platform. Treatment with Gagam-Palmultang reduced acetylcholinesterase activity and expression in the hippocampus induced by scopolamine. The diminished phosphorylated phosphatidylinositide 3-kinase (PI3K, extracellular signal-regulated kinase (ERK, cAMP response element-binding protein (CREB, and mature brain-derived neurotrophic factor (mBDNF expressions caused by scopolamine administration were attenuated by treatment with Gagam-Palmultang. This treatment also promoted neuronal cell proliferation in the hippocampus. Gagam-Palmultang has beneficial effects against scopolamine-induced memory impairments, which are exerted via modulation of the cholinergic system as well as the PI3K and ERK/CREB/BDNF signaling pathway. Therefore, this multiherb formula may be a useful therapeutic agent for diseases associated with memory impairments.

  16. False Operation of Static Random Access Memory Cells under Alternating Current Power Supply Voltage Variation

    Science.gov (United States)

    Sawada, Takuya; Takata, Hidehiro; Nii, Koji; Nagata, Makoto

    2013-04-01

    Static random access memory (SRAM) cores exhibit susceptibility against power supply voltage variation. False operation is investigated among SRAM cells under sinusoidal voltage variation on power lines introduced by direct RF power injection. A standard SRAM core of 16 kbyte in a 90 nm 1.5 V technology is diagnosed with built-in self test and on-die noise monitor techniques. The sensitivity of bit error rate is shown to be high against the frequency of injected voltage variation, while it is not greatly influenced by the difference in frequency and phase against SRAM clocking. It is also observed that the distribution of false bits is substantially random in a cell array.

  17. Terrestrial neutron-induced soft errors in advanced memory devices

    CERN Document Server

    Nakamura, Takashi; Ibe, Eishi; Yahagi, Yasuo; Kameyama, Hideaki

    2008-01-01

    Terrestrial neutron-induced soft errors in semiconductor memory devices are currently a major concern in reliability issues. Understanding the mechanism and quantifying soft-error rates are primarily crucial for the design and quality assurance of semiconductor memory devices. This book covers the relevant up-to-date topics in terrestrial neutron-induced soft errors, and aims to provide succinct knowledge on neutron-induced soft errors to the readers by presenting several valuable and unique features. Sample Chapter(s). Chapter 1: Introduction (238 KB). Table A.30 mentioned in Appendix A.6 on

  18. MEMANTINE ATTENUATES THE OKADAIC ACID INDUCED SHORT-TERM SPATIAL MEMORY IMPAIRMENT AND HIPPOCAMPAL CELL LOSS IN RATS.

    Science.gov (United States)

    Dashniani, M; Chighladze, M; Burjanadze, M; Beselia, G; Kruashvili, L

    2016-03-01

    In the present study, the possible beneficial effect of memantine on the Okadaic Acid (OA) induced spatial short-term memory impairment was examined in spatial alternation task, and the neuroprotective potential of memantine on OA-induced structural changes in the hippocampus was evaluated by Nissl staining. OA was dissolved in artificial cerebrospinal fluid (aCSF) and injected intracerebroventriculary (ICV) 200 ng in a volume of 10 μl bilaterally. Vehicle control received aCSF ICV bilaterally. Control and OA injected rats were divided into 2 subgroups injected i.p. with saline or memantine (5 mg/kg). Memantine or saline were given daily for 13 days starting from the day of OA injection. Behavioral study showed that bilateral ICV microinjection of OA induced impairment in spatial short-term memory. Nissl staining in the present study showed that the ICV microinjection of OA significantly decreased the number of surviving pyramidal neurons in the CA1 region of the hippocampus. Chronic administration of memantine effectively attenuated OA induced spatial short-term memory impairment and the OA-induced neuropathological changes in the hippocampus. Therefore, ICV injection of OA can be used as an experimental model to study mechanisms of neurodegeneration and define novel therapeutics targets for AD pathology.

  19. Revealing past memories: proactive interference and ketamine-induced memory deficits.

    Science.gov (United States)

    Chrobak, James J; Hinman, James R; Sabolek, Helen R

    2008-04-23

    Memories of events that occur often are sensitive to interference from memories of similar events. Proactive interference plays an important and often unexamined role in memory testing for spatially and temporally unique events ("episodes"). Ketamine (NMDA receptor antagonist) treatment in humans and other mammals induces a constellation of cognitive deficits, including impairments in working and episodic memory. We examined the effects of the ketamine (2.5-100 mg/kg) on the acquisition, retrieval, and retention of memory in a delayed-match-to-place radial water maze task that can be used to assess proactive interference. Ketamine (2.5-25 mg/kg, i.p.) given 20 min before the sample trial, impaired encoding. The first errors made during the test trial were predominantly to arms located spatially adjacent to the goal arm, suggesting an established albeit weakened representation. Ketamine (25-100 mg/kg) given immediately after the sample trial had no effect on retention. Ketamine given before the test trial impaired retrieval. First errors under the influence of ketamine were predominantly to the goal location of the previous session. Thus, ketamine treatment promoted proactive interference. These memory deficits were not state dependent, because ketamine treatment at both encoding and retrieval only increased the number of errors during the test session. These data demonstrate the competing influence of distinct memory representations during the performance of a memory task in the rat. Furthermore, they demonstrate the subtle disruptive effects of the NMDA antagonist ketamine on both encoding and retrieval. Specifically, ketamine treatment disrupted retrieval by promoting proactive interference from previous episodic representations.

  20. No effect of stress on false recognition.

    Science.gov (United States)

    Beato, María Soledad; Cadavid, Sara; Pulido, Ramón F; Pinho, María Salomé

    2013-02-01

    The present study aimed to analyze the effect of acute stress on false recognition in the Deese/Roediger-McDermott (DRM) paradigm. In this paradigm, lists of words associated with a non-presented critical lure are studied and, in a subsequent memory test, critical lures are often falsely remembered. In two experiments, participants were randomly assigned to either the stress group (Trier Social Stress Test) or the no-stress control group. Because we sought to control the level-of-processing at encoding, in Experiment 1, participants created a visual mental image for each presented word (deep encoding). In Experiment 2, participants performed a shallow encoding (to respond whether each word contained the letter "o"). The results indicated that, in both experiments, as predicted, heart rate and STAI-S scores increased only in the stress group. However, false recognition did not differ across stress and no-stress groups. Results suggest that, although psychosocial stress was successfully induced, it does not enhance the vulnerability of individuals with acute stress to DRM false recognition, regardless of the level of processing.

  1. False memory for idiomatic expressions in younger and older adults: evidence for indirect activation of figurative meanings.

    Science.gov (United States)

    Coane, Jennifer H; Sánchez-Gutiérrez, Claudia; Stillman, Chelsea M; Corriveau, Jennifer A

    2014-01-01

    Idiomatic expressions can be interpreted literally or figuratively. These two meanings are often processed in parallel or very rapidly, as evidenced by online measures of idiomatic processing. Because in many cases the figurative meaning cannot be derived from the component lexical elements and because of the speed with which this meaning is accessed, it is assumed such meanings are stored in semantic memory. In the present study, we examined how literal equivalents and intact idiomatic expressions are stored in memory and whether episodic memory traces interact or interfere with semantic-level representations and vice versa. To examine age-invariance, younger and older adults studied lists of idioms and literal equivalents. On a recognition test, some studied items were presented in the alternative form (e.g., if the idiom was studied, its literal equivalent was tested). False alarms to these critical items suggested that studying literal equivalents activates the idiom from which they are derived, presumably due to spreading activation in lexical/semantic networks, and results in high rates of errors. Importantly, however, the converse (false alarms to literal equivalents after studying the idiom) were significantly lower, suggesting an advantage in storage for idioms. The results are consistent with idiom processing models that suggest obligatory access to figurative meanings and that this access can also occur indirectly, through literal equivalents.

  2. False memory for idiomatic expressions in younger and older adults: Evidence for indirect activation of figurative meanings

    Directory of Open Access Journals (Sweden)

    Jennifer H Coane

    2014-07-01

    Full Text Available Idiomatic expressions can be interpreted literally or figuratively. These two meanings are often processed in parallel or very rapidly, as evidenced by online measures of idiomatic processing. Because in many cases the figurative meaning cannot be derived from the component lexical elements and because of the speed with which this meaning is accessed, it is assumed such meanings are stored in semantic memory. In the present study, we examined how literal equivalents and intact idiomatic expressions are stored in memory and whether episodic memory traces interact or interfere with semantic-level representations and vice versa. To examine age-invariance, younger and older adults studied lists of idioms and literal equivalents. On a recognition test, some studied items were presented in the alternative form (e.g., if the idiom was studied, its literal equivalent was tested. False alarms to these critical items suggested that studying literal equivalents activates the idiom from which they are derived, presumably due to spreading activation in lexical/semantic networks, and results in high rates of errors. Importantly, however, the converse (false alarms to literal equivalents after studying the idiom were significantly lower, suggesting an advantage in storage for idioms. The results are consistent with idiom processing models that suggest obligatory access to figurative meanings and that this access can also occur indirectly, through literal equivalents.

  3. False recall and recognition of brand names increases over time.

    Science.gov (United States)

    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.

  4. Strong homeostatic TCR signals induce formation of self-tolerant virtual memory CD8 T cells.

    Science.gov (United States)

    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.

  5. [The effect of encoding on false memory: examination on levels of processing and list presentation format].

    Science.gov (United States)

    Hamajima, Hideki

    2004-04-01

    Using the Deese/Roediger-McDermott paradigm, the effects of lists presentation format (blocked/random) and levels of processing of critical nonpresented lures were examined. A levels-of-processing effect in a blocked presentation order was not observed for lures. Rates of false recognition and remember judgments for lures in a shallow level of processing were significantly lower than those in a deep level of processing when items from various themes were inter-mixed instead of blocked. Results showed an interaction between levels of processing and list presentation format. It is thus concluded that encoding of each word and whole list should be both considered in understanding false memory.

  6. L-carnitine prevents memory impairment induced by chronic REM-sleep deprivation.

    Science.gov (United States)

    Alzoubi, Karem H; Rababa'h, Abeer M; Owaisi, Amani; Khabour, Omar F

    2017-05-01

    Sleep deprivation (SD) negatively impacts memory, which was related to oxidative stress induced damage. L-carnitine is a naturally occurring compound, synthesized endogenously in mammalian species and known to possess antioxidant properties. In this study, the effect of L-carnitine on learning and memory impairment induced by rapid eye movement sleep (REM-sleep) deprivation was investigated. REM-sleep deprivation was induced using modified multiple platform model (8h/day, for 6 weeks). Simultaneously, L-carnitine was administered (300mg/kg/day) intraperitoneally for 6 weeks. Thereafter, the radial arm water maze (RAWM) was used to assess spatial learning and memory. Additionally, the hippocampus levels of antioxidant biomarkers/enzymes: reduced glutathione (GSH), oxidized glutathione (GSSG), GSH/GSSG ratio, glutathione peroxidase (GPx), catalase, and superoxide dismutase (SOD) and thiobarbituric acid reactive substance (TBARS) were assessed. The results showed that chronic REM-sleep deprivation impaired both short- and long-term memory (Psleep deprivation induced reduction in the hippocampus ratio of GSH/GSSG, activity of catalase, GPx, and SOD. No change was observed in TBARS among tested groups (P>0.05). In conclusion, chronic REM-sleep deprivation induced memory impairment, and treatment with L-carnitine prevented this impairment through normalizing antioxidant mechanisms in the hippocampus. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Canagliflozin prevents scopolamine-induced memory impairment in rats: Comparison with galantamine hydrobromide action.

    Science.gov (United States)

    Arafa, Nadia M S; Ali, Elham H A; Hassan, Mohamed Kamel

    2017-11-01

    Canagliflozin (CAN) is a sodium-glucose co-transporter 2 (SGLT2) inhibitor indicated to improve glycemic control in adults with type 2 diabetes mellitus. There is a little information about its effect on the cholinergic system that proposed mechanism for memory improvement occurring by SGLT2 drugs. This study aimed to estimate the effect of CAN as compared to galantamine (GAL) treatments for two weeks on scopolamine hydrobromide (SCO)-induced memory dysfunction in experimental rats. Animals divided into six groups; control (CON), CAN, GAL, SCO, SCO + CAN and SCO + GAL. Results indicated significant decrease in body weights of the CAN groups as compared to control values. Moreover, in the SCO + CAN and SCO + GAL the number of arm entry and number of correct alternation in Y maze task increased and showed improvement in the water maze task, acetylcholinesterase (AChE) activities decreased significantly, while monoamines levels significantly increased compared with the SCO group values. Results also recorded acetylcholine M1 receptor (M1 mAChR) in SCO + CAN or SCO + GAL groups in comparison with the SCO group. The study suggested that canagliflozin might improve memory dysfunction induced by scopolamine hydrobromide via cholinergic and monoamines system. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Experimental evolution of olfactory memory in Drosophila melanogaster.

    Science.gov (United States)

    Mery, Frederic; Pont, Juliette; Preat, Thomas; Kawecki, Tadeusz J

    2007-01-01

    In order to address the nature of genetic variation in learning performance, we investigated the response to classical olfactory conditioning in "high-learning" Drosophila melanogaster lines previously subject to selection for the ability to learn an association between the flavor of an oviposition medium and bitter taste. In a T-maze choice test, the seven high-learning lines were better at avoiding an odor previously associated with aversive mechanical shock than were five unselected "low-learning" lines originating from the same natural population. Thus, the evolved improvement in learning ability of high-learning lines generalized to another aversion learning task involving a different aversive stimulus (shock instead of bitter taste) and a different behavioral context than that used to impose selection. In this olfactory shock task, the high-learning lines showed improvements in the learning rate as well as in two forms of consolidated memory: anesthesia-resistant memory and long-term memory. Thus, genetic variation underlying the experimental evolution of learning performance in the high-learning lines affected several phases of memory formation in the course of olfactory aversive learning. However, the two forms of consolidated memory were negatively correlated among replicate high-learning lines, which is consistent with a recent hypothesis that these two forms of consolidated memory are antagonistic.

  9. Irrelevant sound disrupts speech production: exploring the relationship between short-term memory and experimentally induced slips of the tongue.

    Science.gov (United States)

    Saito, Satoru; Baddeley, Alan

    2004-10-01

    To explore the relationship between short-term memory and speech production, we developed a speech error induction technique. The technique, which was adapted from a Japanese word game, exposed participants to an auditory distractor word immediately before the utterance of a target word. In Experiment 1, the distractor words that were phonologically similar to the target word led to a greater number of errors in speaking the target than did the dissimilar distractor words. Furthermore, the speech error scores were significantly correlated with memory span scores. In Experiment 2, memory span scores were again correlated with the rate of the speech errors that were induced from the task-irrelevant speech sounds. Experiment 3 showed a strong irrelevant-sound effect in the serial recall of nonwords. The magnitude of the irrelevant-sound effects was not affected by phonological similarity between the to-be-remembered nonwords and the irrelevant-sound materials. Analysis of recall errors in Experiment 3 also suggested that there were no essential differences in recall error patterns between the dissimilar and similar irrelevant-sound conditions. We proposed two different underlying mechanisms in immediate memory, one operating via the phonological short-term memory store and the other via the processes underpinning speech production.

  10. The effect of BLA GABAB receptors in anxiolytic-like effect and aversive memory deficit induced by ACPA

    Directory of Open Access Journals (Sweden)

    Katayoon Kangarlu Haghighi

    2016-07-01

    Full Text Available Background: As a psychoactive plant, Cannabis sativa (Marijuana is widely used throughout the world. Several investigations have indicated that administration of Marijuana affects various cognitive and non-cognitive behaviors. These include anxiety-like behaviors and learning and memory deficit. It has been shown that three main cannabinoid receptors [i.e. CB1, CB2 and CB3 are involved in cannabinoids’ functions. CB1 receptors are abundantly expressed in the central nervous system regions such as hippocampus, amygdala, cerebellum and the cortex. Therefore, the neuropsychological functions of endocannabinoids are thought to be more linked to CB1 receptors. Among other brain regions, CB1 is highly expressed in the amygdala which is an integral component of the limbic circuitry. The amygdala plays a major role in the control of emotional behavior, including conditioned fear and anxiety. In present study we examined the possible roles of basolateral amygdala (BLA GABAB receptors in arachydonilcyclopropylamide (ACPA-induced anxiolytic-like effect and aversive memory deficit in adult male mice. Methods: This experimental study was conducted from September 2013 to December 2014 in Institute for Studies in Theoretical Physics and Mathematics, School of Cognitive Sciences, Tehran and Male albino NMRI mice (Pasture Institute, Iran, weighting 27-30 g, were used. Bilateral guide-cannulae were implanted to allow intra BLA microinjection of the drugs. We used Elevated Plus Maze (EPM to examine memory and anxiety behavior (test-retest protocol. ACPA administrate intra-peritoneal and GABAB agonist and antagonist administrated intra-amygdala. Results: Data showed that pre-test treatment with ACPA induced anxiolytic-like and aversive memory deficit The results revealed that pre-test intra-BLA infusion of baclofen (GABAB receptor agonist impaired the aversive memory while phaclofen (GABAB receptor antagonist improved it. Interestingly, pretreatment with a sub

  11. Detection of an inhibitory cortical gradient underlying peak shift in learning: a neural basis for a false memory.

    Science.gov (United States)

    Miasnikov, Alexandre A; Weinberger, Norman M

    2012-11-01

    Experience often does not produce veridical memory. Understanding false attribution of events constitutes an important problem in memory research. "Peak shift" is a well-characterized, controllable phenomenon in which human and animal subjects that receive reinforcement associated with one sensory stimulus later respond maximally to another stimulus in post-training stimulus generalization tests. Peak shift ordinarily develops in discrimination learning (reinforced CS+, unreinforced CS-) and has long been attributed to the interaction of an excitatory gradient centered on the CS+ and an inhibitory gradient centered on the CS-; the shift is away from the CS-. In contrast, we have obtained peak shifts during single tone frequency training, using stimulation of the cholinergic nucleus basalis (NB) to implant behavioral memory into the rat. As we also recorded cortical activity, we took the opportunity to investigate the possible existence of a neural frequency gradient that could account for behavioral peak shift. Behavioral frequency generalization gradients (FGGs, interruption of ongoing respiration) were determined twice before training while evoked potentials were recorded from the primary auditory cortex (A1), to obtain a baseline gradient of "habituatory" neural decrement. A post-training behavioral FGG obtained 24h after three daily sessions of a single tone paired with NB stimulation (200 trials/day) revealed a peak shift. The peak of the FGG was at a frequency lower than the CS while the cortical inhibitory gradient was at a frequency higher than the CS frequency. Further analysis indicated that the frequency location and magnitude of the gradient could account for the behavioral peak shift. These results provide a neural basis for a systematic case of memory misattribution and may provide an animal model for the study of the neural bases of a type of "false memory". Published by Elsevier Inc.

  12. The role of α-synuclein and tau hyperphosphorylation-mediated autophagy and apoptosis in lead-induced learning and memory injury.

    Science.gov (United States)

    Zhang, Jianbin; Cai, Tongjian; Zhao, Fang; Yao, Ting; Chen, Yaoming; Liu, Xinqin; Luo, Wenjing; Chen, Jingyuan

    2012-01-01

    Lead (Pb) is a well-known heavy metal in nature. Pb can cause pathophysiological changes in several organ systems including central nervous system. Especially, Pb can affect intelligence development and the ability of learning and memory of children. However, the toxic effects and mechanisms of Pb on learning and memory are still unclear. To clarify the mechanisms of Pb-induced neurotoxicity in hippocampus, and its effect on learning and memory, we chose Sprague-Dawley rats (SD-rats) as experimental subjects. We used Morris water maze to verify the ability of learning and memory after Pb treatment. We used immunohistofluorescence and Western blotting to detect the level of tau phosphorylation, accumulation of α-synuclein, autophagy and related signaling molecules in hippocampus. We demonstrated that Pb can cause abnormally hyperphosphorylation of tau and accumulation of α-synuclein, and these can induce hippocampal injury and the ability of learning and memory damage. To provide the new insight into the underlying mechanisms, we showed that Grp78, ATF4, caspase-3, autophagy-related proteins were induced and highly expressed following Pb-exposure. But mTOR signaling pathway was suppressed in Pb-exposed groups. Our results showed that Pb could cause hyperphosphorylation of tau and accumulation of α-synuclein, which could induce ER stress and suppress mTOR signal pathway. These can enhance type II program death (autophgy) and type I program death (apoptosis) in hippocampus, and impair the ability of learning and memory of rats. This is the first evidence showing the novel role of autophagy in the neurotoxicity of Pb.

  13. Associations between basal cortisol levels and memory retrieval in healthy young individuals

    OpenAIRE

    Ackermann, Sandra; Hartmann, Francina; Papassotiropoulos, Andreas; de Quervain, Dominique J-F; Rasch, Björn

    2013-01-01

    Cortisol is known to affect memory processes. On the one hand, stress-induced or pharmacologically induced elevations of cortisol levels enhance memory consolidation. On the other hand, such experimentally induced elevations of cortisol levels have been shown to impair memory retrieval. However, the effects of individual differences in basal cortisol levels on memory processes remain largely unknown. Here we tested whether individual differences in cortisol levels predict picture learning and...

  14. The Effect of Exercise on Learning and Spatial Memory Following Stress-Induced Sleep Deprivation (Sleep REM in Rats

    Directory of Open Access Journals (Sweden)

    Darkhah

    2016-04-01

    Full Text Available Background Stress induced by sleep deprivation can cause degradation of learning in the acquisition phase, and low-intensity exercise can prevent the negative effects of stress. Objectives The aim of this study was to investigate the moderating role of aerobic exercise on spatial memory and learning following stress-induced insomnia (sleep REM in animal models. Materials and Methods This experimental study was conducted on adult male Wistar rats that were randomly divided into two groups. Both groups were exposed to sleep deprivation induced stress, following which the experimental group was exposed to exercise training (experimental, n = 8; control, n = 8. The stress intervention was undertaken through 24 hours of sleep deprivation using a modified sleep deprivation platform (MMD. The exercise protocol included mild aerobic exercise on a treadmill (30 minutes a day, seven days, and Morris Water Maze (MWM protocols were applied to assess spatial memory and learning. Data were analyzed by an independent t-test and dependent t-test. Results The results showed that, after seven days of aerobic exercise on a treadmill, the experimental group showed better performance escape latency (P < 0.05 and distance traveled (P < 0.05 than the control group in the MWM, while there was no difference between these two groups in the pre-test. Conclusions The role of exercise is greater in the retention than the acquisition phase for recalling past experiences.

  15. Finite element modeling of indentation-induced superelastic effect using a three-dimensional constitutive model for shape memory materials with plasticity

    International Nuclear Information System (INIS)

    Zhang, Yijun; Cheng, Yang-Tse; Grummon, David S.

    2007-01-01

    Indentation-induced shape memory and superelastic effects are recently discovered thermo-mechanical behaviors that may find important applications in many areas of science and engineering. Theoretical understanding of these phenomena is challenging because both martensitic phase transformation and slip plasticity exist under complex contact loading conditions. In this paper, we develop a three-dimensional constitutive model of shape memory alloys with plasticity. Spherical indentation-induced superelasticity in a NiTi shape memory alloy was simulated and compared to experimental results on load-displacement curves and recovery ratios. We show that shallow indents have complete recovery upon unloading, where the size of the phase transformation region is about two times the contact radius. Deep indents have only partial recovery when plastic deformation becomes more prevalent in the indent-affected zone

  16. Stereotype threat reduces false recognition when older adults are forewarned.

    Science.gov (United States)

    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.

  17. Spatial memory: Theoretical basis and comparative review on experimental methods in rodents.

    Science.gov (United States)

    Paul, Carrillo-Mora; Magda, Giordano; Abel, Santamaría

    2009-11-05

    The assessment of learning and memory in animal models has been widely employed in scientific research for a long time. Among these models, those representing diseases with primary processes of affected memory - such as amnesia, dementia, brain aging, etc. - studies dealing with the toxic effects of specific drugs, and other exploring neurodevelopment, trauma, epilepsy and neuropsychiatric disorders, are often called on to employ these tools. There is a diversity of experimental methods assessing animal learning and memory skills. Overall, mazes are the devices mostly used today to test memory in rodents; there are several types of them, but their real usefulness, advantages and applications remain to be fully established and depend on the particular variant selected by the experimenter. The aims of the present article are first, to briefly review the accumulated knowledge in regard to spatial memory tasks; second, to bring the reader information on the different types of rodent mazes available to test spatial memory; and third, to elucidate the usefulness and limitations of each of these devices.

  18. Stochastic memory: Memory enhancement due to noise

    Science.gov (United States)

    Stotland, Alexander; di Ventra, Massimiliano

    2012-01-01

    There are certain classes of resistors, capacitors, and inductors that, when subject to a periodic input of appropriate frequency, develop hysteresis loops in their characteristic response. Here we show that the hysteresis of such memory elements can also be induced by white noise of appropriate intensity even at very low frequencies of the external driving field. We illustrate this phenomenon using a physical model of memory resistor realized by TiO2 thin films sandwiched between metallic electrodes and discuss under which conditions this effect can be observed experimentally. We also discuss its implications on existing memory systems described in the literature and the role of colored noise.

  19. Vacuum-induced quantum memory in an opto-electromechanical system

    Science.gov (United States)

    Qin, Li-Guo; Wang, Zhong-Yang; Wu, Shi-Chao; Gong, Shang-Qing; Ma, Hong-Yang; Jing, Jun

    2018-03-01

    We propose a scheme to implement electrically controlled quantum memory based on vacuum-induced transparency (VIT) in a high-Q tunable cavity, which is capacitively coupled to a mechanically variable capacitor by a charged mechanical cavity mirror as an interface. We analyze the changes of the cavity photons arising from vacuum-induced-Raman process and discuss VIT in an atomic ensemble trapped in the cavity. By slowly adjusting the voltage on the capacitor, the VIT can be adiabatically switched on or off, meanwhile, the transfer between the probe photon state and the atomic spin state can be electrically and adiabatically modulated. Therefore, we demonstrate a vacuum-induced quantum memory by electrically manipulating the mechanical mirror of the cavity based on electromagnetically induced transparency mechanism.

  20. Crocin Improved Learning and Memory Impairments in Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Esmaeal Tamaddonfard

    2013-01-01

    Full Text Available Objective(s: Crocin influences many biological functions including memory and learning. The present study was aimed to investigate the effects of crocin on learning and memory impairments in streptozotocine-induced diabetic rats. Materials and Methods: Diabetes was induced by intraperitoneal (IP injection of streptozotocin (STZ, 45 mg/kg. Transfer latency (TL paradigm in elevated plus-maze (EPM was used as an index of learning and memory. Plasma levels of total antioxidant capacity (TAC and malondialdehyde (MDA, blood levels of glucose, and serum concentrations of insulin were measured. The number of hippocampal neurons was also counted. Results: STZ increased acquisition transfer latency (TL1 and retention transfer latency (TL2, and MDA, decreased transfer latency shortening (TLs and TCA, produced hyperglycemia and hypoinsulinemia, and reduced the number of neurons in the hippocampus. Learning and memory impairments and blood TCA, MDA, glucose, and insulin changes induced by streptozotocin were improved with long-term IP injection of crocin at doses of 15 and 30 mg/kg. Crocin prevented hippocampal neurons number loss in diabetic rats. Conclusion: The results indicate that oxidative stress, hyperglycemia, hypoinsulinemia, and reduction of hippocampal neurons may be involved in learning and memory impairments in STZ-induced diabetic rats. Antioxidant, antihyperglycemic, antihypoinsulinemic, and neuroprotective activities of crocin might be involved in improving learning and memory impairments.

  1. Shape memory alloys applied to improve rotor-bearing system dynamics - an experimental investigation

    DEFF Research Database (Denmark)

    Enemark, Søren; Santos, Ilmar; Savi, Marcelo A.

    2015-01-01

    passing through critical speeds. In this work, the feasibility of applying shape memory alloys to a rotating system is experimentally investigated. Shape memory alloys can change their stiffness with temperature variations and thus they may change system dynamics. Shape memory alloys also exhibit...... perturbations and mass imbalance responses of the rotor-bearing system at different temperatures and excitation frequencies are carried out to determine the dynamic behaviour of the system. The behaviour and the performance in terms of vibration reduction and system adaptability are compared against a benchmark...... configuration comprised by the same system having steel springs instead of shape memory alloy springs. The experimental results clearly show that the stiffness changes and hysteretic behaviour of the shape memory alloys springs alter system dynamics both in terms of critical speeds and mode shapes. Vibration...

  2. Antioxidant hydrolysed peptides from Manchurian walnut (Juglansmandshurica Maxim.) attenuate scopolamine-induced memory impairment in mice.

    Science.gov (United States)

    Ren, Dayong; Zhao, Fanrui; Liu, Chunlei; Wang, Ji; Guo, Yong; Liu, Jingsheng; Min, Weihong

    2018-04-13

    Walnut protein, which is obtained as a by-product of oil expression, has not been used efficiently. Although walnuts are beneficial for cognitive functioning, the potential of their protein composition in strengthening learning and memory functions remains unknown. In this research, the inhibition of memory impairment by the Manchurian walnut hydrolyzed peptide (MWHP) was evaluated. Small-molecular-weight MWHP (<3 kDa) achieved the optimal antioxidative activity. Therefore, MWHP (<3 kDa) was subjected to the following mice trials to evaluate its attenuation effect on memory impairment. In the Morris water maze test, MWHP shortened the total path for searching the platform, reduced the escape latency, and increased the dwelling distance and time in the coverage zone. MWHP also prolonged the latency and diminished errors in the passive avoidance response tests. These behavioral tests demonstrated that MWHP could inhibit scopolamine-induced memory impairment. MWHP improved memory by reducing oxidative stress, inhibiting apoptosis, regulating neurotransmitter functions, maintaining hippocampal CA3 pyramidal neurons, and increasing p-CaMK II levels in brain tissues. Experimental results proved that MWHP exhibits potential in improving memory and should be used to develop novel functional food. This article is protected by copyright. All rights reserved.

  3. False recollection of emotional pictures in Alzheimer's disease.

    Science.gov (United States)

    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.

  4. Experimental Effects of Acute Exercise on Iconic Memory, Short-Term Episodic, and Long-Term Episodic Memory.

    Science.gov (United States)

    Yanes, Danielle; Loprinzi, Paul D

    2018-06-11

    The present experiment evaluated the effects of acute exercise on iconic memory and short- and long-term episodic memory. A two-arm, parallel-group randomized experiment was employed ( n = 20 per group; M age = 21 year). The experimental group engaged in an acute bout of moderate-intensity treadmill exercise for 15 min, while the control group engaged in a seated, time-matched computer task. Afterwards, the participants engaged in a paragraph-level episodic memory task (20 min delay and 24 h delay recall) as well as an iconic memory task, which involved 10 trials (at various speeds from 100 ms to 800 ms) of recalling letters from a 3 × 3 array matrix. For iconic memory, there was a significant main effect for time (F = 42.9, p memory scores at both the baseline (19.22 vs. 17.20) and follow-up (18.15 vs. 15.77), but these results were not statistically significant. These findings provide some suggestive evidence hinting towards an iconic memory and episodic benefit from acute exercise engagement.

  5. The multi-component model of working memory: explorations in experimental cognitive psychology.

    Science.gov (United States)

    Repovs, G; Baddeley, A

    2006-04-28

    There are a number of ways one can hope to describe and explain cognitive abilities, each of them contributing a unique and valuable perspective. Cognitive psychology tries to develop and test functional accounts of cognitive systems that explain the capacities and properties of cognitive abilities as revealed by empirical data gathered by a range of behavioral experimental paradigms. Much of the research in the cognitive psychology of working memory has been strongly influenced by the multi-component model of working memory [Baddeley AD, Hitch GJ (1974) Working memory. In: Recent advances in learning and motivation, Vol. 8 (Bower GA, ed), pp 47-90. New York: Academic Press; Baddeley AD (1986) Working memory. Oxford, UK: Clarendon Press; Baddeley A. Working memory: Thought and action. Oxford: Oxford University Press, in press]. By expanding the notion of a passive short-term memory to an active system that provides the basis for complex cognitive abilities, the model has opened up numerous questions and new lines of research. In this paper we present the current revision of the multi-component model that encompasses a central executive, two unimodal storage systems: a phonological loop and a visuospatial sketchpad, and a further component, a multimodal store capable of integrating information into unitary episodic representations, termed episodic buffer. We review recent empirical data within experimental cognitive psychology that has shaped the development of the multicomponent model and the understanding of the capacities and properties of working memory. Research based largely on dual-task experimental designs and on neuropsychological evidence has yielded valuable information about the fractionation of working memory into independent stores and processes, the nature of representations in individual stores, the mechanisms of their maintenance and manipulation, the way the components of working memory relate to each other, and the role they play in other

  6. Effects of Pre-Experimental Knowledge on Recognition Memory

    Science.gov (United States)

    Bird, Chris M.; Davies, Rachel A.; Ward, Jamie; Burgess, Neil

    2011-01-01

    The influence of pre-experimental autobiographical knowledge on recognition memory was investigated using as memoranda faces that were either personally known or unknown to the participant. Under a dual process theory, such knowledge boosted both recollection- and familiarity-based recognition judgements. Under an unequal variance signal detection…

  7. Grading Gradients: Evaluating Evidence for Time-dependent Memory Reorganization in Experimental Animals

    Directory of Open Access Journals (Sweden)

    Katherine G. Akers

    2009-01-01

    Full Text Available In humans, hippocampal damage typically produces temporally graded retrograde amnesia, with relative sparing of remote memories compared to recent memories. This observation led to the idea that as memories age, they are reorganized in a time-dependent manner. Here, we evaluate evidence for time-dependent memory reorganization in animal models. We conclude that, although hippocampal lesions may not always produce temporal gradients under all conditions, studies using alternate experimental approaches consistently support the idea that memories reorganize over time—becoming less dependent on the hippocampus and more dependent on a cortical network. We further speculate on the processes that drive memory reorganization such as sleep, memory reactivation, synaptic plasticity, and neurogenesis.

  8. Using memories to motivate future behaviour: an experimental exercise intervention.

    Science.gov (United States)

    Biondolillo, Mathew J; Pillemer, David B

    2015-01-01

    This study tested a novel memory-based experimental intervention to increase exercise activity. Undergraduate students completed a two-part online survey ostensibly regarding college activity choices. At Time 1, they completed questionnaires that included assessments of exercise-related attitudes, motivation and self-reported behaviours. Next, they described a memory of a positive or negative experience that would increase their motivation to exercise; students in a control condition did not receive a memory prompt. Finally, they rated their intentions to exercise in the future. Eight days following Time 1, students received a Time 2 survey that included an assessment of their self-reported exercise during the prior week. Students in the positive memory condition reported higher levels of subsequent exercise than those in the control condition; students in the negative memory condition reported intermediate levels of exercise. Activating a positive motivational memory had a significant effect on students' self-reported exercise activity even after controlling for prior attitudes, motivation and exercise activity.

  9. A Deletion Variant of the α2b-Adrenoceptor Modulates the Stress-Induced Shift from "Cognitive" to "Habit" Memory.

    Science.gov (United States)

    Wirz, Lisa; Wacker, Jan; Felten, Andrea; Reuter, Martin; Schwabe, Lars

    2017-02-22

    Stress induces a shift from hippocampus-based "cognitive" toward dorsal striatum-based "habitual" learning and memory. This shift is thought to have important implications for stress-related psychopathologies, including post-traumatic stress disorder (PTSD). However, there is large individual variability in the stress-induced bias toward habit memory, and the factors underlying this variability are completely unknown. Here we hypothesized that a functional deletion variant of the gene encoding the α2b-adrenoceptor ( ADRA2B ), which has been linked to emotional memory processes and increased PTSD risk, modulates the stress-induced shift from cognitive toward habit memory. In two independent experimental studies, healthy humans were genotyped for the ADRA2B deletion variant. After a stress or control manipulation, participants completed a dual-solution learning task while electroencephalographic (Study I) or fMRI measurements (Study II) were taken. Carriers compared with noncarriers of the ADRA2B deletion variant exhibited a significantly reduced bias toward habit memory after stress. fMRI results indicated that, whereas noncarriers of the ADRA2B deletion variant showed increased functional connectivity between amygdala and putamen after stress, this increase in connectivity was absent in carriers of the deletion variant, who instead showed overall enhanced connectivity between amygdala and entorhinal cortex. Our results indicate that a common genetic variation of the noradrenergic system modulates the impact of stress on the balance between cognitive and habitual memory systems, most likely via altered amygdala orchestration of these systems. SIGNIFICANCE STATEMENT Stressful events have a powerful effect on human learning and memory. Specifically, accumulating evidence suggests that stress favors more rigid dorsal striatum-dependent habit memory, at the expense of flexible hippocampus-dependent cognitive memory. Although this shift may have important implications

  10. Similar cold stress induces sex-specific neuroendocrine and working memory responses.

    Science.gov (United States)

    Solianik, Rima; Skurvydas, Albertas; Urboniene, Daiva; Eimantas, Nerijus; Daniuseviciute, Laura; Brazaitis, Marius

    2015-01-01

    Men have higher cold-induced neuroendocrine response than women; nevertheless, it is not known whether a different stress hormone rise elicits different effects on cognition during whole body cooling. The objective was to compare the effect of cold-induced neuroendocrine responses on the performance of working memory sensitive tasks between men and women. The cold stress continued until rectal temperature reached 35.5 degree C or for a maximum of 170 min. Working memory performance and stress hormone concentrations were monitored. During cold stress, body temperature variables dropped in all subjects (P < 0.001) and did not differ between sexes. Cold stress raised plasma epinephrine and serum cortisol levels only in men (P < 0.05). Cold stress adversely affected memory performance in men but not in women (P < 0.05). The present study indicated that similar moderate cold stress in men and women induces sex-specific neuroendocrine and working memory responses.

  11. Beneficial Effect of Leptin on Spatial Learning and Memory in Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Mohsen Ghasemi

    2016-02-01

    Full Text Available Background: Diabetes mellitus is a chronic disease which may be accompanied by cognitive impairments. The expression of the obesity gene (ob is decreased in insulin-deficient diabetic animals and increased after the administration of insulin or leptin. Plasma leptin levels are reduced in the streptozotocin (STZ-induced diabetic rats. Therefore, the deleterious effects of diabetes on memory may be due to the reduction of leptin. Aims: Investigate the effect of subcutaneous injection of leptin on spatial learning and memory in STZ-induced diabetic rats. Study Design: Animal experimentation. Methods: The rats were divided into three groups: 1- control, 2- diabetic, and 3- diabetic-leptin. Diabetes was induced in groups 2 and 3 by STZ injection (55 mg/kg intraperitoneally (i.p. The animals received leptin (0.1 mg/kg or saline subcutaneously (s.c for 10 days before behavioral studies. Then, they were examined in the Morris water maze over 3 blocks after 3 days of the last injection of leptin. Results: The travelled path length and time spent to reach the platform significantly increased in the diabetic group (p<0.001 and decreased with leptin treatment (p<0.01 & p<0.001 respectively; also, a significant increase in path length and time was observed between the diabetic-leptin group and the diabetic group (p<0.01, p<0.001, respectively in the probe test. Conclusion: Leptin can exert positive effects on memory impairments in diabetic rats.

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

    OpenAIRE

    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 tou...

  13. Transcranial Stimulation of the Dorsolateral Prefrontal Cortex Prevents Stress-Induced Working Memory Deficits.

    Science.gov (United States)

    Bogdanov, Mario; Schwabe, Lars

    2016-01-27

    Stress is known to impair working memory performance. This disruptive effect of stress on working memory has been linked to a decrease in the activity of the dorsolateral prefrontal cortex (dlPFC). In the present experiment, we tested whether transcranial direct current stimulation (tDCS) of the dlPFC can prevent stress-induced working memory impairments. We tested 120 healthy participants in a 2 d, sham-controlled, double-blind between-subjects design. Participants completed a test of their individual baseline working memory capacity on day 1. On day 2, participants were exposed to either a stressor or a control manipulation before they performed a visuospatial and a verbal working memory task. While participants completed the tasks, anodal, cathodal, or sham tDCS was applied over the right dlPFC. Stress impaired working memory performance in both tasks, albeit to a lesser extent in the verbal compared with the visuospatial working memory task. This stress-induced working memory impairment was prevented by anodal, but not sham or cathodal, stimulation of the dlPFC. Compared with sham or cathodal stimulation, anodal tDCS led to significantly better working memory performance in both tasks after stress. Our findings indicate a causal role of the dlPFC in working memory impairments after acute stress and point to anodal tDCS as a promising tool to reduce cognitive deficits related to working memory in stress-related mental disorders, such as depression, schizophrenia, or post-traumatic stress disorder. Working memory deficits are prominent in stress-related mental disorders, such as depression, schizophrenia, or post-traumatic stress disorder. Similar working memory impairments have been observed in healthy individuals exposed to acute stress. So far, attempts to prevent such stress-induced working memory deficits focused mainly on pharmacological interventions. Here, we tested the idea that transcranial direct current stimulation of the dorsolateral prefrontal

  14. Preventive Effect of Liothyronine on Electroconvulsive Therapy-Induced Memory Deficit in Patients with Major Depressive Disorder: A Double-Blind Controlled Clinical Trial

    Directory of Open Access Journals (Sweden)

    Arash Mohagheghi

    2015-01-01

    Full Text Available Introduction and Objective. Despite the effectiveness of electroconvulsive therapy (ECT in treating major depressive disorder (MDD, its cognitive side effects make it less popular. This study investigated the impact of liothyronine on ECT-induced memory deficit in patients with MDD. Methodology. This is a double-blind clinical trial, in which 60 patients with MDD who were referred for ECT were selected. The diagnosis was based on the criteria of DSM-IV-TR. Patients were divided randomly into two groups to receive either liothyronine (50 mcg every morning or placebo. After the assessment with Wechsler Memory Scale-Revised (WMS-R before first session of ECT, posttests were repeated again, two months after the completion of ECT. Findings. By controlling the pretest scores, the mean scores of the experimental group were higher than the control group in delayed recall, verbal memory, visual memory, general memory, and attention/concentration scales (P<0.05. Conclusion. Liothyronine may prevent ECT-induced memory impairment in patients with MDD. This study has been registered in IRCT under IRCT201401122660N2.

  15. The influence of strategic encoding on false memory in patients with mild cognitive impairment and Alzheimer's disease dementia.

    Science.gov (United States)

    Tat, Michelle J; Soonsawat, Anothai; Nagle, Corinne B; Deason, Rebecca G; O'Connor, Maureen K; Budson, Andrew E

    2016-11-01

    Patients with Alzheimer's disease (AD) dementia exhibit high rates of memory distortions in addition to their impairments in episodic memory. Several investigations have demonstrated that when healthy individuals (young and old) engaged in an encoding strategy that emphasized the uniqueness of study items (an item-specific encoding strategy), they were able to improve their discrimination between old items and unstudied critical lure items in a false memory task. In the present study we examined if patients with AD could also improve their memory discrimination when engaging in an item-specific encoding strategy. Healthy older adult controls, patients with mild cognitive impairment (MCI) due to AD, and patients with mild AD dementia were asked to study lists of categorized words. In the Item-Specific condition, participants were asked to provide a unique detail or personal experience with each study item. In the Relational condition, they were asked to determine how each item in the list was related to the others. To assess the influence of both strategies, recall and recognition memory tests were administered. Overall, both patient groups exhibited poorer memory in both recall and recognition tests compared to controls. In terms of recognition, healthy older controls and patients with MCI due to AD exhibited improved memory discrimination in the Item-Specific condition compared to the Relational condition, whereas patients with AD dementia did not. We speculate that patients with MCI due to AD use intact frontal networks to effectively engage in this strategy. Published by Elsevier Inc.

  16. Basolateral amygdala GABA-A receptors mediate stress-induced memory retrieval impairment in rats.

    Science.gov (United States)

    Sardari, Maryam; Rezayof, Ameneh; Khodagholi, Fariba; Zarrindast, Mohammad-Reza

    2014-04-01

    The present study was designed to investigate the involvement of GABA-A receptors of the basolateral amygdala (BLA) in the impairing effect of acute stress on memory retrieval. The BLAs of adult male Wistar rats were bilaterally cannulated and memory retrieval was measured in a step-through type passive avoidance apparatus. Acute stress was evoked by placing the animals on an elevated platform for 10, 20 and 30 min. The results indicated that exposure to 20 and 30 min stress, but not 10 min, before memory retrieval testing (pre-test exposure to stress) decreased the step-through latency, indicating stress-induced memory retrieval impairment. Intra-BLA microinjection of a GABA-A receptor agonist, muscimol (0.005-0.02 μg/rat), 5 min before exposure to an ineffective stress (10 min exposure to stress) induced memory retrieval impairment. It is important to note that pre-test intra-BLA microinjection of the same doses of muscimol had no effect on memory retrieval in the rats unexposed to 10 min stress. The blockade of GABA-A receptors of the BLA by injecting an antagonist, bicuculline (0.4-0.5 μg/rat), 5 min before 20 min exposure to stress, prevented stress-induced memory retrieval. Pre-test intra-BLA microinjection of the same doses of bicuculline (0.4-0.5 μg/rat) in rats unexposed to 20 min stress had no effect on memory retrieval. In addition, pre-treatment with bicuculline (0.1-0.4 μg/rat, intra-BLA) reversed muscimol (0.02 μg/rat, intra-BLA)-induced potentiation on the effect of stress in passive avoidance learning. It can be concluded that pre-test exposure to stress can induce memory retrieval impairment and the BLA GABA-A receptors may be involved in stress-induced memory retrieval impairment.

  17. Output Position and Word Relatedness Effects in a DRM Paradigm: Support for a Dual-Retrieval Process Theory of Free Recall and False Memories

    Science.gov (United States)

    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…

  18. Developmental Differences in the Effects of Repeated Interviews and Interviewer Bias on Young Children’s Event Memory and False Reports

    Science.gov (United States)

    Quas, Jodi A.; Malloy, Lindsay C.; Melinder, Annika; Goodman, Gail S.; D’Mello, Michelle; Schaaf, Jennifer

    2010-01-01

    The present study investigated developmental differences in the effects of repeated interviews and interviewer bias on children’s memory and suggestibility. Three- and 5-year-olds were singly or repeatedly interviewed about a play event by a highly biased or control interviewer. Children interviewed once by the biased interviewer after a long delay made the most errors. Children interviewed repeatedly, regardless of interviewer bias, were more accurate and less likely to falsely claim that they played with a man. In free recall, among children questioned once after a long delay by the biased interviewer, 5-year-olds were more likely than were 3-year-olds to claim falsely that they played with a man. However, in response to direct questions, 3-year-olds were more easily manipulated into implying that they played with him. Findings suggest that interviewer bias is particularly problematic when children’s memory has weakened. In contrast, repeated interviews that occur a short time after a to-be-remembered event do not necessarily increase children’s errors, even when interviews include misleading questions and interviewer bias. Implications for developmental differences in memory and suggestibility are discussed. PMID:17605517

  19. The ironic effect of guessing: increased false memory for mediated lists in younger and older adults

    Science.gov (United States)

    Coane, Jennifer H.; Huff, Mark J.; Hutchison, Keith A.

    2016-01-01

    Younger and older adults studied lists of words directly (e.g., creek, water) or indirectly (e.g., beaver, faucet) related to a nonpresented critical lure (CL; e.g., river). Indirect (i.e., mediated) lists presented items that were only related to CLs through nonpresented mediators (i.e., directly related items). Following study, participants completed a condition-specific task, math, a recall test with or without a warning about the CL, or tried to guess the CL. On a final recognition test, warnings (vs. math and recall without warning) decreased false recognition for direct lists, and guessing increased mediated false recognition (an ironic effect of guessing) in both age groups. The observed age-invariance of the ironic effect of guessing suggests that processes involved in mediated false memory are preserved in aging and confirms the effect is largely due to activation in semantic networks during encoding and to the strengthening of these networks during the interpolated tasks. PMID:26393390

  20. Studies of short and long memory in mining-induced seismic processes

    Science.gov (United States)

    Węglarczyk, Stanisław; Lasocki, Stanisław

    2009-09-01

    Memory of a stochastic process implies its predictability, understood as a possibility to gain information on the future above the random guess level. Here we search for memory in the mining-induced seismic process (MIS), that is, a process induced or triggered by mining operations. Long memory is investigated by means of the Hurst rescaled range analysis, and the autocorrelation function estimate is used to test for short memory. Both methods are complemented with result uncertainty analyses based on different resampling techniques. The analyzed data comprise event series from Rudna copper mine in Poland. The studies show that the interevent time and interevent distance processes have both long and short memory. MIS occurrences and locations are internally interrelated. Internal relations among the sizes of MIS events are apparently weaker than those of other two studied parameterizations and are limited to long term interactions.

  1. Spatial Memory in the Progeny of Rats Subjected to Different Types of Experimental Preeclampsia.

    Science.gov (United States)

    Perfilova, V N; Zhakupova, G A; Lashchenova, L I; Lebedeva, S A; Tyurenkov, I N

    2016-09-01

    Spatial memory was studied in 2-month-old offspring of rats subjected to different types of experimental preeclampsia (replacement of drinking water with 1.8% NaCl from day 1 to 21 of gestation or intraperitoneal administration of non-selective NO-synthase inhibitor L-NAME to pregnant rats in a daily dose of 25 mg/kg for 7 days on gestation days 14-20). Spatial memory was evaluated in an elevated 8-arm radial maze. Both types of experimental preeclampsia impaired spatial (long-term and short-term) memory and can be used in the development of drugs correcting negative effects of this pregnancy complication on memory.

  2. Extinction antagonizes olfactory memory at the subcellular level.

    Science.gov (United States)

    Schwaerzel, Martin; Heisenberg, Martin; Zars, Troy

    2002-08-29

    Memory loss occurs by diverse mechanisms, as different time constants of performance decrement and sensitivities to experimental manipulations suggest. While the phenomena of memory decay, interference, and extinction are well established behaviorally, little is known about them at the circuit or molecular level. In Drosophila, odorant memories lasting up to 3 hr can be localized to mushroom body Kenyon cells, a single neuronal level in the olfactory pathway. The plasticity underlying this memory trace can be induced without Kenyon cell synaptic output. Experimental extinction, i.e., presentation of the conditioned stimulus without the reinforcer, reduces memory performance and does so at the same circuit level as memory formation. Thus, unreinforced presentation of learned odorants antagonizes intracellularly the signaling cascade underlying memory formation.

  3. Modifying Memory: Selectively Enhancing and Updating Personal Memories for a Museum Tour by Reactivating Them

    Science.gov (United States)

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

    2013-01-01

    Memory can be modified when reactivated, but little is known about how the properties and extent of reactivation can selectively affect subsequent memory. We developed a novel museum paradigm to directly investigate reactivation-induced plasticity for personal memories. Participants reactivated memories triggered by photos taken from a camera they wore during a museum tour and made relatedness judgments on novel photos taken from a different tour of the same museum. Subsequent recognition memory for events at the museum was better for memories that were highly reactivated (i.e., the retrieval cues during reactivation matched the encoding experience) than for memories that were reactivated at a lower level (i.e., the retrieval cues during reactivation mismatched the encoding experience), but reactivation also increased false recognition of photographs depicting stops that were not experienced during the museum tour. Reactivation thus enables memories to be selectively enhanced and distorted via updating, thereby supporting the dynamic and flexible nature of memory. PMID:23406611

  4. Stereotype threat can reduce older adults' memory errors.

    Science.gov (United States)

    Barber, Sarah J; Mather, Mara

    2013-01-01

    Stereotype threat often incurs the cost of reducing the amount of information that older adults accurately recall. In the current research, we tested whether stereotype threat can also benefit memory. According to the regulatory focus account of stereotype threat, threat induces a prevention focus in which people become concerned with avoiding errors of commission and are sensitive to the presence or absence of losses within their environment. Because of this, we predicted that stereotype threat might reduce older adults' memory errors. Results were consistent with this prediction. Older adults under stereotype threat had lower intrusion rates during free-recall tests (Experiments 1 and 2). They also reduced their false alarms and adopted more conservative response criteria during a recognition test (Experiment 2). Thus, stereotype threat can decrease older adults' false memories, albeit at the cost of fewer veridical memories, as well.

  5. The Malleability of Developmental Trends in Neutral and Negative Memory Illusions

    Science.gov (United States)

    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

  6. The synthetic cannabinoid HU210 induces spatial memory deficits and suppresses hippocampal firing rate in rats.

    Science.gov (United States)

    Robinson, L; Goonawardena, A V; Pertwee, R G; Hampson, R E; Riedel, G

    2007-07-01

    Previous work implied that the hippocampal cannabinoid system was particularly important in some forms of learning, but direct evidence for this hypothesis is scarce. We therefore assessed the effects of the synthetic cannabinoid HU210 on memory and hippocampal activity. HU210 (100 microg kg(-1)) was administered intraperitoneally to rats under three experimental conditions. One group of animals were pre-trained in spatial working memory using a delayed-matching-to-position task and effects of HU210 were assessed in a within-subject design. In another, rats were injected before acquisition learning of a spatial reference memory task with constant platform location. Finally, a separate group of animals was implanted with electrode bundles in CA1 and CA3 and single unit responses were isolated, before and after HU210 treatment. HU210 treatment had no effect on working or short-term memory. Relative to its control Tween 80, deficits in acquisition of a reference memory version of the water maze were obtained, along with drug-related effects on anxiety, motor activity and spatial learning. Deficits were not reversed by the CB(1) receptor antagonists SR141716A (3 mg kg(-1)) or AM281 (1.5 mg kg(-1)). Single unit recordings from principal neurons in hippocampal CA3 and CA1 confirmed HU210-induced attenuation of the overall firing activity lowering both the number of complex spikes fired and the occurrence of bursts. These data provide the first direct evidence that the underlying mechanism for the spatial memory deficits induced by HU210 in rats is the accompanying abnormality in hippocampal cell firing.

  7. The influence of strategic encoding on false memory in patients with mild cognitive impairment and Alzheimer’s disease dementia

    Science.gov (United States)

    Tat, Michelle J.; Soonsawat, Anothai; Nagle, Corinne B.; Deason, Rebecca G.; O’Connor, Maureen K.; Budson, Andrew E.

    2018-01-01

    Patients with Alzheimer’s disease (AD) dementia exhibit high rates of memory distortions in addition to their impairments in episodic memory. Several investigations have demonstrated that when healthy individuals (young and old) engaged in an encoding strategy that emphasized the uniqueness of study items (an item-specific encoding strategy), they were able to improve their discrimination between old items and unstudied critical lure items in a false memory task. In the present study we examined if patients with AD could also improve their memory discrimination when engaging in an item-specific encoding strategy. Healthy older adult controls, patients with mild cognitive impairment (MCI) due to AD, and patients with mild AD dementia were asked to study lists of categorized words. In the Item-Specific condition, participants were asked to provide a unique detail or personal experience with each study item. In the Relational condition, they were asked to determine how each item in the list was related to the others. To assess the influence of both strategies, recall and recognition memory tests were administered. Overall, both patient groups exhibited poorer memory in both recall and recognition tests compared to controls. In terms of recognition, healthy older controls and patients with MCI due to AD exhibited improved memory discrimination in the Item-Specific condition compared to the Relational condition, whereas patients with AD dementia did not. We speculate that patients with MCI due to AD use intact frontal networks to effectively engage in this strategy. PMID:27643951

  8. Experimental analyses of dynamical systems involving shape memory alloys

    DEFF Research Database (Denmark)

    Enemark, Søren; Savi, Marcelo A.; Santos, Ilmar F.

    2015-01-01

    The use of shape memory alloys (SMAs) in dynamical systems has an increasing importance in engineering especially due to their capacity to provide vibration reductions. In this regard, experimental tests are essential in order to show all potentialities of this kind of systems. In this work, SMA ...

  9. Glucocorticoids mediate stress-induced impairment of retrieval of stimulus-response memory.

    Science.gov (United States)

    Atsak, Piray; Guenzel, Friederike M; Kantar-Gok, Deniz; Zalachoras, Ioannis; Yargicoglu, Piraye; Meijer, Onno C; Quirarte, Gina L; Wolf, Oliver T; Schwabe, Lars; Roozendaal, Benno

    2016-05-01

    Acute stress and elevated glucocorticoid hormone levels are well known to impair the retrieval of hippocampus-dependent 'declarative' memory. Recent findings suggest that stress might also impair the retrieval of non-hippocampal memories. In particular, stress shortly before retention testing was shown to impair the retrieval of striatal stimulus-response associations in humans. However, the mechanism underlying this stress-induced retrieval impairment of non-hippocampal stimulus-response memory remains elusive. In the present study, we investigated whether an acute elevation in glucocorticoid levels mediates the impairing effects of stress on retrieval of stimulus-response memory. Male Sprague-Dawley rats were trained on a stimulus-response task in an eight-arm radial maze until they learned to associate a stimulus, i.e., cue, with a food reward in one of the arms. Twenty-four hours after successful acquisition, they received a systemic injection of vehicle, corticosterone (1mg/kg), the corticosterone-synthesis inhibitor metyrapone (35mg/kg) or were left untreated 1h before retention testing. We found that the corticosterone injection impaired the retrieval of stimulus-response memory. We further found that the systemic injection procedure per se was stressful as the vehicle administration also increased plasma corticosterone levels and impaired the retrieval of stimulus-response memory. However, memory retrieval was not impaired when rats were tested 2min after the systemic vehicle injection, before any stress-induced elevation in corticosterone levels had occurred. Moreover, metyrapone treatment blocked the effect of injection stress on both plasma corticosterone levels and memory retrieval impairment, indicating that the endogenous corticosterone response mediates the stress-induced memory retrieval impairment. None of the treatments affected rats' locomotor activity or motivation to search for the food reward within the maze. These findings show that stress

  10. Piracetam prevents memory deficit induced by postnatal propofol exposure in mice.

    Science.gov (United States)

    Wang, Yuan-Lin; Li, Feng; Chen, Xin

    2016-05-15

    Postnatal propofol exposure impairs hippocampal synaptic development and memory. However, the effective agent to alleviate the impairments was not verified. In this study, piracetam, a positive allosteric modulator of AMPA receptor was administered following a seven-day propofol regime. Two months after propofol administration, hippocampal long-term potentiation (LTP) and long-term memory decreased, while intraperitoneal injection of piracetam at doses of 100mg/kg and 50mg/kg following last propofol exposure reversed the impairments of memory and LTP. Mechanically, piracetam reversed propofol exposure-induced decrease of BDNF and phosphorylation of mTor. Similar as piracetam, BDNF supplementary also ameliorated propofol-induced abnormalities of synaptic plasticity-related protein expressions, hippocampal LTP and long-term memory. These results suggest that piracetam prevents detrimental effects of propofol, likely via activating BDNF synthesis. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. The emotional and reconstructive determinants of emotional memories: an experimental approach to flashbulb memory investigation.

    Science.gov (United States)

    Lanciano, Tiziana; Curci, Antonietta; Semin, Gun R

    2010-07-01

    Flashbulb memories (FBMs) are vivid and detailed memories of the reception context of a public emotional event. Brown and Kulik (1977) introduced the label FBM to suggest the idea that individuals are able to preserve knowledge of an event in an indiscriminate way, in analogy with a photograph that preserves all details of a scene. Research work on FBMs has primarily been conducted using a naturalistic approach in order to explore the role of the emotional and reconstructive factors on FBM formation and maintenance. Nevertheless, these studies lack a sufficient control on the factors that might intervene in the process of FBM formation. The contribution of the present studies is addressed to experimentally investigating the role of emotional and reconstructive factors on emotionally charged memories, specifically on FBMs. Paralleling FBM findings, the two studies revealed that simply being in an emotional state allows people to remember all available information, such as irrelevant and unrelated details. Furthermore, the resulting memories are affected by reconstructive processes so that they are not as accurate as their richness of details would suggest.

  12. Chemical memory reactions induced bursting dynamics in gene expression.

    Science.gov (United States)

    Tian, Tianhai

    2013-01-01

    Memory is a ubiquitous phenomenon in biological systems in which the present system state is not entirely determined by the current conditions but also depends on the time evolutionary path of the system. Specifically, many memorial phenomena are characterized by chemical memory reactions that may fire under particular system conditions. These conditional chemical reactions contradict to the extant stochastic approaches for modeling chemical kinetics and have increasingly posed significant challenges to mathematical modeling and computer simulation. To tackle the challenge, I proposed a novel theory consisting of the memory chemical master equations and memory stochastic simulation algorithm. A stochastic model for single-gene expression was proposed to illustrate the key function of memory reactions in inducing bursting dynamics of gene expression that has been observed in experiments recently. The importance of memory reactions has been further validated by the stochastic model of the p53-MDM2 core module. Simulations showed that memory reactions is a major mechanism for realizing both sustained oscillations of p53 protein numbers in single cells and damped oscillations over a population of cells. These successful applications of the memory modeling framework suggested that this innovative theory is an effective and powerful tool to study memory process and conditional chemical reactions in a wide range of complex biological systems.

  13. Experimental sleep deprivation as a tool to test memory deficits in rodents

    Directory of Open Access Journals (Sweden)

    VALERIA eCOLAVITO

    2013-12-01

    Full Text Available Paradigms of sleep deprivation (SD and memory testing in rodents (laboratory rats and mice are here reviewed. The vast majority of these studies have been aimed at understanding the contribution of sleep to cognition, and in particular to memory. Relatively little attention, instead, has been devoted to SD as a challenge to induce a transient memory impairment, and therefore as a tool to test cognitive enhancers in drug discovery. The purpose of this article is to provide an overview of the studies that have accurately described methodological aspects of the SD protocol and behavioral paradigm in order to critically assess them and propose SD protocols that could be employed as cognitive challenge. Total SD, partial or state-selective SD (rapid eye movement SD procedures are first reviewed, followed by procedures to investigate SD-induced impairment of learning and memory consolidation. Thus, a platform of knowledge is here provided for laboratory protocols that could be used to assess the efficacy of drugs designed to improve memory performance in rodents, including rodent models of neurodegenerative diseases that cause cognitive deficits, and Alzheimer’s disease in particular. Issues in the interpretation of such preclinical data and their predictive value for clinical translation are also discussed.

  14. Two-way shape memory effect induced by repetitive compressive loading cycles

    International Nuclear Information System (INIS)

    Kim, Hyun-Chul; Yoo, Young-Ik; Lee, Jung-Ju

    2009-01-01

    The NiTi alloy can be trained by repetitive loading or heating cycles. As a result of the training, a two-way shape memory effect (TWSME) can be induced. Considerable research has been reported regarding the TWSME trained by tensile loading. However, the TWSME trained by compressive loading has not been investigated nearly as much. In this paper, the TWSME is induced by compressive loading cycles and the two-way shape memory strain is evaluated by using two types of specimen: a solid cylinder type and a tube type. The TWSME trained by compressive loading is different from that trained by tensile loading owing to the severe tension/compression asymmetry as described in previous research. After repetitive compressive loading cycles, strain variation upon cooling is observed, and this result proves that the TWSME is induced by compressive loading cycles. By performing compressive loading cycles, plastic deformation in NiTi alloy occurs more than for tensile loading cycles, which brings about the appearance of TWSME. It can be said that the TWSME is induced by compressive loading cycles more easily. The two-way shape memory strain increases linearly as the maximum strain of compressive loading cycles increases, regardless of the shape and the size of the NiTi alloy; this two-way shape memory strain then shows a tendency towards saturation after some repeated cycles

  15. The influence of working memory capacity on experimental heat pain.

    Science.gov (United States)

    Nakae, Aya; Endo, Kaori; Adachi, Tomonori; Ikeda, Takashi; Hagihira, Satoshi; Mashimo, Takashi; Osaka, Mariko

    2013-10-01

    Pain processing and attention have a bidirectional interaction that depends upon one's relative ability to use limited-capacity resources. However, correlations between the size of limited-capacity resources and pain have not been evaluated. Working memory capacity, which is a cognitive resource, can be measured using the reading span task (RST). In this study, we hypothesized that an individual's potential working memory capacity and subjective pain intensity are related. To test this hypothesis, we evaluated 31 healthy participants' potential working memory capacity using the RST, and then applied continuous experimental heat stimulation using the listening span test (LST), which is a modified version of the RST. Subjective pain intensities were significantly lower during the challenging parts of the RST. The pain intensity under conditions where memorizing tasks were performed was compared with that under the control condition, and it showed a correlation with potential working memory capacity. These results indicate that working memory capacity reflects the ability to process information, including precise evaluations of changes in pain perception. In this work, we present data suggesting that changes in subjective pain intensity are related, depending upon individual potential working memory capacities. Individual working memory capacity may be a phenotype that reflects sensitivity to changes in pain perception. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.

  16. Trust and Cheating in Sri Lanka: The Role of Experimentally-Induced Emotions about Tsunam

    OpenAIRE

    Pierluigi Conzo

    2014-01-01

    Through a field experiment in Sri Lanka I analyze the role of experimentally-induced memories of 2004 tsunami on behavior in a trust game in which personal notions of cheating are elicited. Microfinance borrowers were randomly assigned to a treatment (control) group consisting in watching a video about the calamity before (after) playing. Trust game participants were asked how much to receive (return) in order not to (make the counterpart) feel cheated; in a survey they selected whether the v...

  17. Are addiction-related memories malleable by working memory competition? Transient effects on memory vividness and nicotine craving in a randomized lab experiment.

    Science.gov (United States)

    Markus, Wiebren; de Weert-van Oene, Gerdien H; Woud, Marcella L; Becker, Eni S; DeJong, Cornelis A J

    2016-09-01

    Experimental research suggests that working memory (WM) taxation reduces craving momentarily. Using a modified Eye Movement Desensitization and Reprocessing (EMDR) procedure, prolonged reductions in craving and relapse rates in alcohol dependence have been demonstrated. Modified EMDR-procedures may also hold promise in smoking cessation attempts. A proof-of-concept study was conducted to narrow the gap between WM-taxation experiments and clinical EMDR studies. To this end the clinical EMDR-procedure was modified for use in a laboratory experiment. Daily smokers (n = 47), abstaining overnight, were allocated (by minimization randomization) to one of two groups using a parallel design. In both cases a modified EMDR-procedure was used. In the experimental group (n = 24) eye movements (EM) were induced while control group participants (n = 23) fixed their gaze (not taxing WM). During 6 min trials, craving-inducing memories were recalled. Craving, vividness of target memories, and smoking behavior were assessed at several variable-specific time-points between baseline (one week pre-intervention) and one week follow-up. The experimental group showed significant immediate reductions of craving and vividness of targeted memories. However, these effects were lost during a one-week follow-up period. A limited dose of WM-taxation, in the form of EM in a modified EMDR-procedure, resulted in transient effects on memory vividness and nicotine craving. EM provide a valuable way of coping with the acute effects of craving during smoking cessation attempts. Other aspects of the EMDR-procedure may provide additional effects. Component and dose-response studies are needed to establish the potential of EMDR-therapy in smoking cessation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Nuclear war as false memory

    Directory of Open Access Journals (Sweden)

    John Timberlake

    2014-10-01

    Full Text Available In this paper Timberlake outlines aspects of his creative practice as an artist, explaining his fascination for the ‘fictions of nuclear war’ – a war that never happened and so became the subject of ‘false memory’. Highlighting discontinued historical trajectories, the author shows how the cultural legacy of Britain’s nuclear test programme of the 1950s and ’60s may be explored meaningfully in paintings and photography resulting from his archival research at the Imperial War Museum in London.

  19. AC-3933, a benzodiazepine partial inverse agonist, improves memory performance in MK-801-induced amnesia mouse model.

    Science.gov (United States)

    Hashimoto, Takashi; Iwamura, Yoshihiro

    2016-05-01

    AC-3933, a novel benzodiazepine receptor partial inverse agonist, is a drug candidate for cognitive disorders including Alzheimer's disease. We have previously reported that AC-3933 enhances acetylcholine release in the rat hippocampus and ameliorates scopolamine-induced memory impairment and age-related cognitive decline in both rats and mice. In this study, we further evaluated the procognitive effect of AC-3933 on memory impairment induced by MK-801, an N-methyl-d-aspartate receptor antagonist, in mice. Unlike the acetylcholinesterase inhibitor donepezil and the benzodiazepine receptor inverse agonist FG-7142, oral administration of AC-3933 significantly ameliorated MK-801-induced memory impairment in the Y-maze test and in the object location test. Interestingly, the procognitive effects of AC-3933 on MK-801-induced memory impairment were not affected by the benzodiazepine receptor antagonist flumazenil, although this was not the case for the beneficial effects of AC-3933 on scopolamine-induced memory deficit. Moreover, the onset of AC-3933 ameliorating effect on scopolamine- or MK-801-induced memory impairment was different in the Y-maze test. Taken together, these results indicate that AC-3933 improves memory deficits caused by both cholinergic and glutamatergic hypofunction and suggest that the ameliorating effect of AC-3933 on MK-801-induced memory impairment is mediated by a mechanism other than inverse activation of the benzodiazepine receptor. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. The novel dehydroepiandrosterone (DHEA) derivative BNN27 counteracts delay-dependent and scopolamine-induced recognition memory deficits in rats.

    Science.gov (United States)

    Pitsikas, Nikolaos; Gravanis, Achille

    2017-04-01

    Experimental evidence indicates that the neurosteroids dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS) are involved in cognition. BNN27 is a novel 17C spiroepoxy-DHEA derivative, which devoid of steroidogenic activity. The neuroprotective effects of BNN27 have been recently reported. The present study was designed to investigate the effects of BNN27 on recognition memory in rats. For this purpose, the novel object task (NOT), a procedure assessing non-spatial recognition memory and the novel location task (NLT), a procedure evaluating spatial recognition memory were used. Intraperitoneal (i.p.) administration of BNN27 (3 and 10mg/kg) antagonized delay-dependent deficits in the NOT in the normal rat, suggesting that this DHEA derivative affected acquisition, storage and retrieval of information. In addition, BNN27 (3 and 10mg/kg, i.p.) counteracted the scopolamine [0.2mg/kg, subcutaneously (s.c.)]-induced non-spatial and spatial recognition memory deficits. These findings suggest that BNN27 may modulate different aspects of recognition memory, potentially interacting with the cholinergic system, relevant to cognition. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Decision-related factors in pupil old/new effects: Attention, response execution, and false memory.

    Science.gov (United States)

    Brocher, Andreas; Graf, Tim

    2017-07-28

    In this study, we investigate the effects of decision-related factors on recognition memory in pupil old/new paradigms. In Experiment 1, we used an old/new paradigm with words and pseudowords and participants made lexical decisions during recognition rather than old/new decisions. Importantly, participants were instructed to focus on the nonword-likeness of presented items, not their word-likeness. We obtained no old/new effects. In Experiment 2, participants discriminated old from new words and old from new pseudowords during recognition, and they did so as quickly as possible. We found old/new effects for both words and pseudowords. In Experiment 3, we used materials and an old/new design known to elicit a large number of incorrect responses. For false alarms ("old" response for new word), we found larger pupils than for correctly classified new items, starting at the point at which response execution was allowed (2750ms post stimulus onset). In contrast, pupil size for misses ("new" response for old word) was statistically indistinguishable from pupil size in correct rejections. Taken together, our data suggest that pupil old/new effects result more from the intentional use of memory than from its automatic use. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Pheromone-Induced Olfactory Memory in Newborn Rabbits: Involvement of Consolidation and Reconsolidation Processes

    Science.gov (United States)

    Coureaud, Gerard; Languille, Solene; Schaal, Benoist; Hars, Bernard

    2009-01-01

    Mammary pheromone (MP)-induced odor memory is a new model of appetitive memory functioning early in a mammal, the newborn rabbit. Some properties of this associative memory are analyzed by the use of anisomycin as an amnesic agent. Long-term memory (LTM) was impaired by anisomycin delivered immediately, but not 4 h after either acquisition or…

  3. Uncovering Camouflage: Amygdala Activation Predicts Long-Term Memory of Induced Perceptual Insight

    Science.gov (United States)

    Ludmer, Rachel; Dudai, Yadin; Rubin, Nava

    2012-01-01

    What brain mechanisms underlie learning of new knowledge from single events? We studied encoding in long-term memory of a unique type of one-shot experience, induced perceptual insight. While undergoing an fMRI brain scan, participants viewed degraded images of real-world pictures where the underlying objects were hard to recognize (‘camouflage’), followed by brief exposures to the original images (‘solution’), which led to induced insight (“Aha!”). A week later, participants’ memory was tested; a solution image was classified as ‘remembered’ if detailed perceptual knowledge was elicited from the camouflage image alone. During encoding, subsequently remembered images enjoyed higher activity in mid-level visual cortex and medial frontal cortex, but most pronouncedly in the amygdala, whose activity could be used to predict which solutions will remain in long-term memory. Our findings extend the known roles of amygdala in memory to include promoting of long-term memory of the sudden reorganization of internal representations. PMID:21382558

  4. Dopamine D1 receptors are responsible for stress-induced emotional memory deficit in mice.

    Science.gov (United States)

    Wang, Yongfu; Wu, Jing; Zhu, Bi; Li, Chaocui; Cai, Jing-Xia

    2012-03-01

    It is established that stress impairs spatial learning and memory via the hypothalamus-pituitary-adrenal axis response. Dopamine D1 receptors were also shown to be responsible for a stress-induced deficit of working memory. However, whether stress affects the subsequent emotional learning and memory is not elucidated yet. Here, we employed the well-established one-trial step-through task to study the effect of an acute psychological stress (induced by tail hanging for 5, 10, or 20 min) on emotional learning and memory, and the possible mechanisms as well. We demonstrated that tail hanging induced an obvious stress response. Either an acute tail-hanging stress or a single dose of intraperitoneally injected dopamine D1 receptor antagonist (SCH23390) significantly decreased the step-through latency in the one-trial step-through task. However, SCH23390 prevented the acute tail-hanging stress-induced decrease in the step-through latency. In addition, the effects of tail-hanging stress and/or SCH23390 on the changes in step-through latency were not through non-memory factors such as nociceptive perception and motor function. Our data indicate that the hyperactivation of dopamine D1 receptors mediated the stress-induced deficit of emotional learning and memory. This study may have clinical significance given that psychological stress is considered to play a role in susceptibility to some mental diseases such as depression and post-traumatic stress disorder.

  5. The optimal timing of stimulation to induce long-lasting positive effects on episodic memory in physiological aging.

    Science.gov (United States)

    Manenti, Rosa; Sandrini, Marco; Brambilla, Michela; Cotelli, Maria

    2016-09-15

    Episodic memory displays the largest degree of age-related decline. A noninvasive brain stimulation technique that can be used to modulate memory in physiological aging is transcranial Direct Current Stimulation (tDCS). However, an aspect that has not been adequately investigated in previous studies is the optimal timing of stimulation to induce long-lasting positive effects on episodic memory function. Our previous studies showed episodic memory enhancement in older adults when anodal tDCS was applied over the left lateral prefrontal cortex during encoding or after memory consolidation with or without a contextual reminder. Here we directly compared the two studies to explore which of the tDCS protocols would induce longer-lasting positive effects on episodic memory function in older adults. In addition, we aimed to determine whether subjective memory complaints would be related to the changes in memory performance (forgetting) induced by tDCS, a relevant issue in aging research since individuals with subjective memory complaints seem to be at higher risk of later memory decline. The results showed that anodal tDCS applied after consolidation with a contextual reminder induced longer-lasting positive effects on episodic memory, conceivably through reconsolidation, than anodal tDCS during encoding. Furthermore, we reported, providing new data, a moderate negative correlation between subjective memory complaints and forgetting when anodal tDCS was applied after consolidation with a contextual reminder. This study sheds light on the best-suited timing of stimulation to induce long-lasting positive effects on memory function and might help the clinicians to select the most effective tDCS protocol to prevent memory decline. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Differential effects of stress-induced cortisol responses on recollection and familiarity-based recognition memory.

    Science.gov (United States)

    McCullough, Andrew M; Ritchey, Maureen; Ranganath, Charan; Yonelinas, Andrew

    2015-09-01

    Stress-induced changes in cortisol can impact memory in various ways. However, the precise relationship between cortisol and recognition memory is still poorly understood. For instance, there is reason to believe that stress could differentially affect recollection-based memory, which depends on the hippocampus, and familiarity-based recognition, which can be supported by neocortical areas alone. Accordingly, in the current study we examined the effects of stress-related changes in cortisol on the processes underlying recognition memory. Stress was induced with a cold-pressor test after incidental encoding of emotional and neutral pictures, and recollection and familiarity-based recognition memory were measured one day later. The relationship between stress-induced cortisol responses and recollection was non-monotonic, such that subjects with moderate stress-related increases in cortisol had the highest levels of recollection. In contrast, stress-related cortisol responses were linearly related to increases in familiarity. In addition, measures of cortisol taken at the onset of the experiment showed that individuals with higher levels of pre-learning cortisol had lower levels of both recollection and familiarity. The results are consistent with the proposition that hippocampal-dependent memory processes such as recollection function optimally under moderate levels of stress, whereas more cortically-based processes such as familiarity are enhanced even with higher levels of stress. These results indicate that whether post-encoding stress improves or disrupts recognition memory depends on the specific memory process examined as well as the magnitude of the stress-induced cortisol response. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Veridical and false recall in adults who stutter.

    Science.gov (United States)

    Byrd, Courtney T; Sheng, Li; Ratner, Nan Bernstein; Gkalitsiou, Zoi

    2015-02-01

    This study used a false memory paradigm to explore the veridical and false recall of adults who stutter. Twelve adults who stutter and 12 age-matched typically fluent peers listened to and then verbally recalled lists of words that consisted of either semantic or phonological associates or an equal number of semantic and phonological associates (i.e., hybrid condition) of a single, unpresented critical "lure" word. Three parameters of recall performance were measured across these 3 conditions: (a) number of accurately recalled words, (b) order of recall (primacy vs. recency effect), and (c) number of critical lures produced (i.e., false memories). Significant group differences were noted in recall accuracy specific to list type and also list position as well as relative to critical lure productions. Results suggest that certain basic memory processes (i.e., recency effect) and the processing of gist semantic information are largely intact in adults who stutter, but recall of verbatim phonological information and subvocal rehearsal may be deficient.

  8. Alcohol-induced retrograde memory impairment in rats: prevention by caffeine.

    Science.gov (United States)

    Spinetta, Michael J; Woodlee, Martin T; Feinberg, Leila M; Stroud, Chris; Schallert, Kellan; Cormack, Lawrence K; Schallert, Timothy

    2008-12-01

    Ethanol and caffeine are two of the most widely consumed drugs in the world, often used in the same setting. Animal models may help to understand the conditions under which incidental memories formed just before ethanol intoxication might be lost or become difficult to retrieve. Ethanol-induced retrograde amnesia was investigated using a new odor-recognition test. Rats thoroughly explored a wood bead taken from the cage of another rat, and habituated to this novel odor (N1) over three trials. Immediately following habituation, rats received saline, 25 mg/kg pentylenetetrazol (a seizure-producing agent known to cause retrograde amnesia) to validate the test, 1.0 g/kg ethanol, or 3.0 g/kg ethanol. The next day, they were presented again with N1 and also a bead from a new rat's cage (N2). Rats receiving saline or the lower dose of ethanol showed overnight memory for N1, indicated by preferential exploration of N2 over N1. Rats receiving pentylenetetrazol or the higher dose of ethanol appeared not to remember N1, in that they showed equal exploration of N1 and N2. Caffeine (5 mg/kg), delivered either 1 h after the higher dose of ethanol or 20 min prior to habituation to N1, negated ethanol-induced impairment of memory for N1. A combination of a phosphodiesterase-5 inhibitor and an adenosine A(2A) antagonist, mimicking two major mechanisms of action of caffeine, likewise prevented the memory impairment, though either drug alone had no such effect. Binge alcohol can induce retrograde, caffeine-reversible disruption of social odor memory storage or recall.

  9. Memory-induced nonlinear dynamics of excitation in cardiac diseases.

    Science.gov (United States)

    Landaw, Julian; Qu, Zhilin

    2018-04-01

    Excitable cells, such as cardiac myocytes, exhibit short-term memory, i.e., the state of the cell depends on its history of excitation. Memory can originate from slow recovery of membrane ion channels or from accumulation of intracellular ion concentrations, such as calcium ion or sodium ion concentration accumulation. Here we examine the effects of memory on excitation dynamics in cardiac myocytes under two diseased conditions, early repolarization and reduced repolarization reserve, each with memory from two different sources: slow recovery of a potassium ion channel and slow accumulation of the intracellular calcium ion concentration. We first carry out computer simulations of action potential models described by differential equations to demonstrate complex excitation dynamics, such as chaos. We then develop iterated map models that incorporate memory, which accurately capture the complex excitation dynamics and bifurcations of the action potential models. Finally, we carry out theoretical analyses of the iterated map models to reveal the underlying mechanisms of memory-induced nonlinear dynamics. Our study demonstrates that the memory effect can be unmasked or greatly exacerbated under certain diseased conditions, which promotes complex excitation dynamics, such as chaos. The iterated map models reveal that memory converts a monotonic iterated map function into a nonmonotonic one to promote the bifurcations leading to high periodicity and chaos.

  10. The Effect of Divided Attention on Emotion-Induced Memory Narrowing

    Science.gov (United States)

    Steinmetz, Katherine R. Mickley; Waring, Jill D.; Kensinger, Elizabeth A.

    2014-01-01

    Individuals are more likely to remember emotional than neutral information, but this benefit does not always extend to the surrounding background information. This memory narrowing is theorized to be linked to the availability of attentional resources at encoding. In contrast to the predictions of this theoretical account, altering participants’ attentional resources at encoding, by dividing attention, did not affect the emotion-induced memory narrowing. Attention was divided using three separate manipulations: a digit ordering task (Experiment 1), an arithmetic task (Experiment 2), and an auditory discrimination task (Experiment 3). Across all three experiments, divided attention decreased memory across-the-board but did not affect the degree of memory narrowing. These findings suggest that theories to explain memory narrowing must be expanded to include other potential mechanisms beyond limitations of attentional resources. PMID:24295041

  11. The effect of divided attention on emotion-induced memory narrowing.

    Science.gov (United States)

    Mickley Steinmetz, Katherine R; Waring, Jill D; Kensinger, Elizabeth A

    2014-01-01

    Individuals are more likely to remember emotional than neutral information, but this benefit does not always extend to the surrounding background information. This memory narrowing is theorised to be linked to the availability of attentional resources at encoding. In contrast to the predictions of this theoretical account, altering participants' attentional resources at encoding by dividing attention did not affect emotion-induced memory narrowing. Attention was divided using three separate manipulations: a digit ordering task (Experiment 1), an arithmetic task (Experiment 2) and an auditory discrimination task (Experiment 3). Across all three experiments, divided attention decreased memory across the board but did not affect the degree of memory narrowing. These findings suggest that theories to explain memory narrowing must be expanded to include other potential mechanisms beyond the limitations of attentional resources.

  12. Highly Efficient Coherent Optical Memory Based on Electromagnetically Induced Transparency

    Science.gov (United States)

    Hsiao, Ya-Fen; Tsai, Pin-Ju; Chen, Hung-Shiue; Lin, Sheng-Xiang; Hung, Chih-Chiao; Lee, Chih-Hsi; Chen, Yi-Hsin; Chen, Yong-Fan; Yu, Ite A.; Chen, Ying-Cheng

    2018-05-01

    Quantum memory is an important component in the long-distance quantum communication based on the quantum repeater protocol. To outperform the direct transmission of photons with quantum repeaters, it is crucial to develop quantum memories with high fidelity, high efficiency and a long storage time. Here, we achieve a storage efficiency of 92.0 (1.5)% for a coherent optical memory based on the electromagnetically induced transparency scheme in optically dense cold atomic media. We also obtain a useful time-bandwidth product of 1200, considering only storage where the retrieval efficiency remains above 50%. Both are the best record to date in all kinds of schemes for the realization of optical memory. Our work significantly advances the pursuit of a high-performance optical memory and should have important applications in quantum information science.

  13. Flexible Retrieval: When True Inferences Produce False Memories

    Science.gov (United States)

    Carpenter, Alexis C.; Schacter, Daniel L.

    2017-01-01

    Episodic memory involves flexible retrieval processes that allow us to link together distinct episodes, make novel inferences across overlapping events, and recombine elements of past experiences when imagining future events. However, the same flexible retrieval and recombination processes that underpin these adaptive functions may also leave…

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

    Science.gov (United States)

    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.

  15. Pluto behaving badly: false beliefs and their consequences.

    Science.gov (United States)

    Berkowitz, Shari R; Laney, Cara; Morris, Erin K; Garry, Maryanne; Loftus, Elizabeth F

    2008-01-01

    We exposed college students to suggestive materials in order to lead them to believe that, as children, they had a negative experience at Disneyland involving the Pluto character. A sizable minority of subjects developed a false belief or memory that Pluto had uncomfortably licked their ear. Suggestions about a positive experience with Pluto led to even greater acceptance of a lovable ear-licking episode. False beliefs and memories had repercussions; those seduced by the bad suggestions were not willing to pay as much for a Pluto souvenir. These findings are among the first to demonstrate that false beliefs can have repercussions for people, meaning that they can influence their later thoughts, beliefs, and behaviors.

  16. Novelty exposure overcomes foot shock-induced spatial-memory impairment by processes of synaptic-tagging in rats.

    Science.gov (United States)

    Almaguer-Melian, William; Bergado-Rosado, Jorge; Pavón-Fuentes, Nancy; Alberti-Amador, Esteban; Mercerón-Martínez, Daymara; Frey, Julietta U

    2012-01-17

    Novelty processing can transform short-term into long-term memory. We propose that this memory-reinforcing effect of novelty could be explained by mechanisms outlined in the "synaptic tagging hypothesis." Initial short-term memory is sustained by a transient plasticity change at activated synapses and sets synaptic tags. These tags are later able to capture and process the plasticity-related proteins (PRPs), which are required to transform a short-term synaptic change into a long-term one. Novelty is involved in inducing the synthesis of PRPs [Moncada D, et al. (2011) Proc Natl Acad Sci USA 108:12937-12936], which are then captured by the tagged synapses, consolidating memory. In contrast to novelty, stress can impair learning, memory, and synaptic plasticity. Here, we address questions as to whether novelty-induced PRPs are able to prevent the loss of memory caused by stress and if the latter would not interact with the tag-setting process. We used water-maze (WM) training as a spatial learning paradigm to test our hypothesis. Stress was induced by a strong foot shock (FS; 5 × 1 mA, 2 s) applied 5 min after WM training. Our data show that FS reduced long-term but not short-term memory in the WM paradigm. This negative effect on memory consolidation was time- and training-dependent. Interestingly, novelty exposure prevented the stress-induced memory loss of the spatial task and increased BDNF and Arc expression. This rescuing effect was blocked by anisomycin, suggesting that WM-tagged synapses were not reset by FS and were thus able to capture the novelty-induced PRPs, re-establishing FS-impaired long-term memory.

  17. Amnesia induced by morphine in spatial memory retrieval inhibited in morphine-sensitized rats.

    Science.gov (United States)

    Farahmandfar, Maryam; Naghdi, Nasser; Karimian, Seyed Morteza; Kadivar, Mehdi; Zarrindast, Mohammad-Reza

    2012-05-15

    The present study investigated the effect of morphine sensitization on the impairment of spatial memory retrieval induced by acute morphine in adult male rats. Spatial memory was assessed by 2-day Morris water maze task which included training and test day. On the training day, rats were trained by a single training session of 8 trials. On the test day, a probe trial consisting of 60s free swim period without a platform and the visible test were administered. Morphine sensitization was induced by subcutaneous (s.c.) injection of morphine, once daily for 3 days followed by 5 days without drug treatment before training. The results indicated that acute administration of morphine (7.5mg/kg, s.c.) before testing impaired spatial memory on the test day. Pre-test morphine-induced amnesia decreased in morphine-sensitized (15 and 20mg/kg, s.c.) rats. Improvement in spatial memory retrieval in morphine-sensitized rats was inhibited by once daily administration of naloxone (1 and 2mg/kg, s.c.) 30 min prior to the injection of morphine for three days. The results suggest that morphine sensitization reverses the impairment of spatial memory retrieval induced by acute morphine and it is implied that mu-opioid receptors may play an important role in this effect. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Phosphodiesterase 10A inhibition attenuates sleep deprivation-induced deficits in long-term fear memory.

    Science.gov (United States)

    Guo, Lengqiu; Guo, Zhuangli; Luo, Xiaoqing; Liang, Rui; Yang, Shui; Ren, Haigang; Wang, Guanghui; Zhen, Xuechu

    2016-12-02

    Sleep, particularly rapid eye movement (REM) sleep, is implicated in the consolidation of emotional memories. In the present study, we investigated the protective effects of a phosphodiesterase 10A (PDE10A) inhibitor MP-10 on deficits in long-term fear memory induced by REM sleep deprivation (REM-SD). REM-SD caused deficits in long-term fear memory, however, MP-10 administration ameliorated the deleterious effects of REM-SD on long term fear memory. Brain-derived neurotropic factor (BDNF) and phosphorylated cAMP response element-binding protein (pCREB) were altered in specific brain regions associated with learning and memory in REM-SD rats. Accordingly, REM-SD caused a significant decrease of pCREB in hippocampus and striatum and a significant decrease of BDNF in the hippocampus, striatum and amygdala, however, MP-10 reversed the effects of REM-SD in a dose-dependent manner. Our findings suggest that REM-SD disrupts the consolidation of long-term fear memory and that administration of MP-10 protects the REM-SD-induced deficits in fear memory, which may be due to the MP-10-induced expression of BDNF in the hippocampus, striatum and amygdala, and phosphorylation of CREB in the hippocampus and striatum. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Children's False Memory for Emotional Events: A Developmental Perspective on Emotion s Impact on Backwards Causal-Inference Errors.

    OpenAIRE

    Vennerød, Frida Felicia

    2014-01-01

    The present study examines how emotion affects false memory formation using the Backwards Causal-Inference Paradigm, with a developmental perspective. One-hundred-and-thirty-two children participated in the study, with 56 children aged 6-8 years, 43 children aged 9-10 years and 33 children aged 11-12 years. The children were presented with one of six different PowerPoints, which all displayed the same scripts in photographs, but differed in emotional (positive vs. negative vs. neutral) outcom...

  20. An Experimental Analysis of Memory Processing

    OpenAIRE

    Wright, Anthony A

    2007-01-01

    Rhesus monkeys were trained and tested in visual and auditory list-memory tasks with sequences of four travel pictures or four natural/environmental sounds followed by single test items. Acquisitions of the visual list-memory task are presented. Visual recency (last item) memory diminished with retention delay, and primacy (first item) memory strengthened. Capuchin monkeys, pigeons, and humans showed similar visual-memory changes. Rhesus learned an auditory memory task and showed octave gener...

  1. Analysis of simultaneous multi-bit induced by a cosmic ray for onboard memory

    International Nuclear Information System (INIS)

    Ono, Takashi; Mori, Masato

    1987-01-01

    Accompanying the development of intelligent onboard equipment using high density memories, the soft-error phenomenon, which is the bit upset induced by a cosmic ray, must be investigated. Especially, the simultaneous multi-bit error (SME) induced by a cosmic ray negligible on earth becomes remarkable in space use. This paper entimates the SME occurrence rate of memory chip by computer simulations and describes the results of the SME experiments using a cyclotron. The computer simulation and experiment results confirm the SME occurrence and show that layout of memory cells is important for the probability of SME occurrence. (author)

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

    Science.gov (United States)

    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.

  3. False Memories Seconds Later: The Rapid and Compelling Onset of Illusory Recognition

    Science.gov (United States)

    Flegal, Kristin E.; Atkins, Alexandra S.; Reuter-Lorenz, Patricia A.

    2010-01-01

    Distortions of long-term memory (LTM) in the converging associates task are thought to arise from semantic associative processes and monitoring failures due to degraded verbatim and/or contextual memory. Sensory-based coding is traditionally considered more prevalent than meaning-based coding in short-term memory (STM), whereas the converse is…

  4. Inhibitory effect of Thymus vulgaris extract on memory impairment induced by scopolamine in rat简

    Institute of Scientific and Technical Information of China (English)

    Zahra; Rabiei; Shiva; Mokhtari; Samira; Asgharzade; Mostafa; Gholami; Samira; Rahnama; Mahmoud; Rafieian-kopaei

    2015-01-01

    Objective: To investigate the effect of Thymus vulgaris(T. vulgaris) on learning and memory functions in scopolamine-induced memory deficit in rats. Memory enhancing activity in scopolamine-induced amnesic rats was investigated by assessing the Morris water maze and passive avoidance paradigm.Methods: A total of 42 male Wistar rats were divided into 6 equal groups as follow:control group: received water, scopolamine treated group: received scopolamine 1 mg/kg for 15 days, two scopolamine + T. vulgaris treated groups: received scopolamine and T. vulgaris extract 50 and 100 mg/kg body weight per day for 15 days, two intact groups:received T. vulgaris extract 50 and 100 mg/kg body weight per day for 15 days.Results: Administration of T. vulgaris extract significantly restored memory and learning impairments induced by scopolamine in the passive avoidance test and Morris water maze test.Conclusions: T. vulgaris extract has repairing effects on memory and behavioral disorders produced by scopolamine and may have beneficial effects in the treatment of Alzheimer’s disease.

  5. The neural correlates of gist-based true and false recognition

    Science.gov (United States)

    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

  6. The Effect of Divided Attention on Emotion-Induced Memory Narrowing

    OpenAIRE

    Steinmetz, Katherine R. Mickley; Waring, Jill D.; Kensinger, Elizabeth A.

    2013-01-01

    Individuals are more likely to remember emotional than neutral information, but this benefit does not always extend to the surrounding background information. This memory narrowing is theorized to be linked to the availability of attentional resources at encoding. In contrast to the predictions of this theoretical account, altering participants’ attentional resources at encoding, by dividing attention, did not affect the emotion-induced memory narrowing. Attention was divided using three sepa...

  7. The role of state anxiety in children's memories for pain.

    Science.gov (United States)

    Noel, Melanie; Chambers, Christine T; McGrath, Patrick J; Klein, Raymond M; Stewart, Sherry H

    2012-06-01

    To investigate the impact of experimentally manipulated state anxiety and the influence of anxiety-related variables on children's memories for pain. A total of 110 children (60 boys) between the ages of 8 and 12 years were randomly assigned to complete a state anxiety induction task or a control task. Following experimental manipulation, children completed a laboratory pain task, pain ratings, and questionnaire measures of anxiety-related variables. 2 weeks later, children provided pain ratings based on their memories of the pain task. The experimental manipulation effectively induced state anxiety; however, pain memories did not differ between groups. Irrespective of group assignment, children with higher state anxiety had more negative pain memories. State anxiety uniquely predicted children's pain memories over and above other well established factors. Anxiety sensitivity and trait anxiety were significant predictors of recalled pain-related fear. These data highlight the importance of anxiety in the development of children's memories for pain.

  8. Experimental Model of Cerebral Hypoperfusion Produced Memory-learning Deficits, and Modifications in Gene Expression

    Directory of Open Access Journals (Sweden)

    Rilda LEÓN

    2015-01-01

    Full Text Available Cerebral ischemia is a major cause of death, for this reason animal models of cerebral ischemia are widely used to study both the pathophysiology of ischemic phenomenon and the evaluation of possible therapeutic agents with protective or regenerative properties. The objectives of this study were to examine the presence of neuronal damage in different brain areas following the ischemic event, and assess consequences of such activities on the processes of memory and learning. The study group included an experimental group ischemic animals (30 rats with permanent bilateral occlusion of the carotids, and a control group. Was evaluated gene expression and inflammatory ischemic by qPCR techniques 24h post injury, brain tissue morphology in areas of cortex, striatum and hippocampus seven days post injury and processes of memory and learning, 12 days post injury. The morphological studies showed that the procedure induces death of cell populations in cortex, striatum and hippocampus, ischemia modified gfap gene expression and ho, il-6, il-17 and ifn-γ, which can be used as a marker of early ischemic process. Additionally, the ischemic injury caused spatial memory decline. This characterization gives us an experimental model to develop future studies on the pathophysiology of ischemic events and assessing therapeutic strategies. MODELO EXPERIMENTAL DE HIPOPERFUSIÓN CEREBRAL PRODUCE DÉFICIT DE LA MEMORIA Y APRENDIZAJE Y MODIFICACIONES EN LA EXPRESIÓN DE GENES. A escala mundial, la isquemia cerebral constituye una de las principales causas de muerte, por lo que los modelos animales de isquemia cerebral son extensamente usados tanto en el estudio de la pato-fisiología del fenómeno isquémico; como en la evaluación de agentes terapéuticos con posible efecto protector o regenerador.  Los objetivos de este estudio fueron examinar la presencia de daño neuronal en diferentes áreas cerebrales como consecuencia del evento isquémico; así como evaluar

  9. Experimental study on reactor neutron induced effect of deep sub-micron CMOS static random access memory

    International Nuclear Information System (INIS)

    Yang Shanchao; Guo Xiaoqiang; Lin Dongsheng; Chen Wei; Li Ruibin; Bai Xiaoyan; Wang Guizhen

    2010-01-01

    This paper investigates neutron irradiation effects of two kinds of commercial CMOS SRAM (static random access memory), of which one is 4M memory with the feature size of 0.25 μm and the other is 16M memory with the feature size of 0.13 μm. We designed a memory testing system of irradiation effects and performed the neutron irradiation experiment using the Xi'an Pulse Reactor. The upset of two kinds of memory cells did not present a threshold versus the increase of neutron fluence. The results showed that deep sub-micron SRAM behaved single-event upset (SEU) effect in neutron irradiation environment. The SEU effect of SRAM with smaller size and higher integrated level tends to upset is considered to be related to the reduction of the device feature size, and fewer charges for upsets of the memory cell also lead to the SEU effect. (authors)

  10. Oligonol improves memory and cognition under an amyloid β(25-35)-induced Alzheimer's mouse model.

    Science.gov (United States)

    Choi, Yoon Young; Maeda, Takahiro; Fujii, Hajime; Yokozawa, Takako; Kim, Hyun Young; Cho, Eun Ju; Shibamoto, Takayuki

    2014-07-01

    Alzheimer's disease is an age-dependent progressive neurodegenerative disorder that results in impairments of memory and cognitive function. It is hypothesized that oligonol has ameliorative effects on memory impairment and reduced cognitive functions in mice with Alzheimer's disease induced by amyloid β(25-35) (Aβ(25-35)) injection. The protective effect of an oligonol against Aβ(25-35)-induced memory impairment was investigated in an in vivo Alzheimer's mouse model. The aggregation of Aβ25-35 was induced by incubation at 37°C for 3 days before injection into mice brains (5 nmol/mouse), and then oligonol was orally administered at 100 and 200 mg/kg of body weight for 2 weeks. Memory and cognition were observed in T-maze, object recognition, and Morris water maze tests. The group injected with Aβ(25-35) showed impairments in both recognition and memory. However, novel object recognition and new route awareness abilities were dose dependently improved by the oral administration of oligonol. In addition, the results of the Morris water maze test indicated that oligonol exerted protective activity against cognitive impairment induced by Aβ(25-35). Furthermore, nitric oxide formation and lipid peroxidation were significantly elevated by Aβ(25-35), whereas oligonol treatment significantly decreased nitric oxide formation and lipid peroxidation in the brain, liver, and kidneys. The present results suggest that oligonol improves Aβ(25-35)-induced memory deficit and cognition impairment. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Learning induces the translin/trax RNase complex to express activin receptors for persistent memory

    NARCIS (Netherlands)

    Park, Alan Jung; Havekes, Robbert; Fu, Xiuping; Hansen, Rolf; Tudor, Jennifer C; Peixoto, Lucia; Li, Zhi; Wu, Yen-Ching; Poplawski, Shane G; Baraban, Jay M; Abel, Ted

    2017-01-01

    Long-lasting forms of synaptic plasticity and memory require de novo protein synthesis. Yet, how learning triggers this process to form memory is unclear. Translin/trax is a candidate to drive this learning-induced memory mechanism by suppressing microRNA-mediated translational silencing at

  12. Novelty-induced emotional arousal modulates cannabinoid effects on recognition memory and adrenocortical activity.

    Science.gov (United States)

    Campolongo, Patrizia; Morena, Maria; Scaccianoce, Sergio; Trezza, Viviana; Chiarotti, Flavia; Schelling, Gustav; Cuomo, Vincenzo; Roozendaal, Benno

    2013-06-01

    Although it is well established that cannabinoid drugs can influence cognitive performance, the findings-describing both enhancing and impairing effects-have been ambiguous. Here, we investigated the effects of posttraining systemic administration of the synthetic cannabinoid agonist WIN55,212-2 (0.1, 0.3, or 1.0 mg/kg) on short- and long-term retention of object recognition memory under two conditions that differed in their training-associated arousal level. In male Sprague-Dawley rats that were not previously habituated to the experimental context, WIN55,212-2 administered immediately after a 3-min training trial, biphasically impaired retention performance at a 1-h interval. In contrast, WIN55,212-2 enhanced 1-h retention of rats that had received extensive prior habituation to the experimental context. Interestingly, immediate posttraining administration of WIN55,212-2 to non-habituated rats, in doses that impaired 1-h retention, enhanced object recognition performance at a 24-h interval. Posttraining WIN55,212-2 administration to habituated rats did not significantly affect 24-h retention. In light of intimate interactions between cannabinoids and the hypothalamic-pituitary-adrenal axis, we further investigated whether cannabinoid administration might differently influence training-induced glucocorticoid activity in rats in these two habituation conditions. WIN55,212-2 administered after object recognition training elevated plasma corticosterone levels in non-habituated rats whereas it decreased corticosterone levels in habituated rats. Most importantly, following pretreatment with the corticosterone-synthesis inhibitor metyrapone, WIN55,212-2 effects on 1- and 24-h retention of non-habituated rats became similar to those seen in the low-aroused habituated animals, indicating that cannabinoid-induced regulation of adrenocortical activity contributes to the environmentally sensitive effects of systemically administered cannabinoids on short- and long

  13. Memantine prevents memory consolidation failure induced by soluble beta amyloid in rats

    Directory of Open Access Journals (Sweden)

    Paolo eTucci

    2014-09-01

    Full Text Available It has been well documented that β-amyloid peptide accumulation and aggregation in the brain plays a crucial role in the pathophysiology of Alzheimer’s disease (AD. However, a new orientation of the amyloid cascade hypothesis has evidenced that soluble forms of the peptide (sAβ are involved in Aβ-induced cognitive impairment and cause rapid disruption of the synaptic mechanisms underlying memory. The primary aim of this study was to elucidate the effects of sAβ, acutely injected intracerebrally (i.c.v., 4 µM, on the short term and long term memory of young adult male rats, by using the novel object recognition task. Glutamatergic receptors have been proposed as mediating the effect of Aβ on synaptic plasticity and memory. Thus, we also investigated the effects of sAβ on prefrontal cortex (PFC glutamate release and the specific contribution of N-methyl-D-aspartate (NMDA receptor modulation to the effects of sAβ administration on the cognitive parameters evaluated. We found that a single i.c.v. injection of sAβ 2h before testing did not alter the ability of rats to differentiate between a familiar and a novel object, in a short term memory test, while it was able to negatively affect consolidation/retrieval of long term memory. Moreover, a significant increase of glutamate levels was found in PFC of rats treated with the peptide 2 h earlier. Interestingly, memory deficit induced by sAβ was reversed by a NMDA-receptor antagonist, memantine (5 mg/kg i.p, administered immediately after the familiarization trial (T1. On the contrary, memantine administered 30 min before T1 trial, was not able to rescue long term memory impairment. Taken together, our results suggest that an acute i.c.v. injection of sAβ peptide interferes with the consolidation/retrieval of long term memory. Moreover, such sAβ-induced effect indicates the involvement of glutamatergic system, proposing that NMDA receptor inhibition might prevent or lead to the recovery of

  14. Activating the critical lure during study is unnecessary for false recognition.

    Science.gov (United States)

    Zeelenberg, René; Boot, Inge; Pecher, Diane

    2005-06-01

    Participants studied lists of nonwords (e.g., froost, floost, stoost, etc.) that were orthographic-phonologically similar to a nonpresented critical lure, which was also a nonword (e.g., ploost). Experiment 1 showed a high level of false recognition for the critical lure. Experiment 2 showed that the false recognition effect was also present for forewarned participants who were informed about the nature of the false recognition effect and told to avoid making false recognition judgments. The present results show that false recognition effects can be obtained even when the critical lure itself is not stored during study. This finding is problematic for accounts that attribute false memories to implicit associative responses or spreading activation but is easily explained by global familiarity models of recognition memory.

  15. Photo-induced optical activity in phase-change memory materials.

    Science.gov (United States)

    Borisenko, Konstantin B; Shanmugam, Janaki; Williams, Benjamin A O; Ewart, Paul; Gholipour, Behrad; Hewak, Daniel W; Hussain, Rohanah; Jávorfi, Tamás; Siligardi, Giuliano; Kirkland, Angus I

    2015-03-05

    We demonstrate that optical activity in amorphous isotropic thin films of pure Ge2Sb2Te5 and N-doped Ge2Sb2Te5N phase-change memory materials can be induced using rapid photo crystallisation with circularly polarised laser light. The new anisotropic phase transition has been confirmed by circular dichroism measurements. This opens up the possibility of controlled induction of optical activity at the nanosecond time scale for exploitation in a new generation of high-density optical memory, fast chiroptical switches and chiral metamaterials.

  16. Portulaca oleracea L. prevents lipopolysaccharide-induced passive avoidance learning and memory and TNF-α impairments in hippocampus of rat.

    Science.gov (United States)

    Noorbakhshnia, Maryam; Karimi-Zandi, Leila

    2017-02-01

    There is a growing body of evidence that neuroinflammation can impair memory. It has been indicated that Portulaca oleracea Linn. (POL), possess anti-inflammatory activity and might improve memory disruption caused by inflammation. In this study the effect of pre-treatment with the hydro-alcoholic extract of POL on memory retrieval investigated in lipopolysaccharide (LPS) treated rats. Male Wistar rats (200-220g) received either a control diet or a diet containing of POL (400mg/kg, p.o.) for 14days. Then, they received injections of either saline or LPS (1mg/kg, i.p.). In all the experimental groups, 4h following the last injection, passive avoidance learning (PAL) and memory test was performed. The retention test was done 24h after the training and then the animals were sacrificed. Hippocampal TNF-α levels measured using ELISA as one criteria of LPS-induced neuroinflammation. The results indicated that LPS significantly impaired PAL and memory and increased TNF-α levels in hippocampus tissue. Pre-treatment with POL improved memory in control rats and prevented memory and TNF-α deterioration in LPS treated rats. Taken together, the results of this study suggest that the hydro-alcoholic extract of POL may improve memory deficits in LPS treated rats, possibly via inhibition of TNF-α and anti-inflammatory activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Indoleamine 2,3-dioxygenase-dependent neurotoxic kynurenine metabolism mediates inflammation-induced deficit in recognition memory.

    Science.gov (United States)

    Heisler, Jillian M; O'Connor, Jason C

    2015-11-01

    Cognitive dysfunction in depression is a prevalent and debilitating symptom that is poorly treated by the currently available pharmacotherapies. Research over the past decade has provided evidence for proinflammatory involvement in the neurobiology of depressive disorders and symptoms associated with these disorders, including aspects of memory dysfunction. Recent clinical studies implicate inflammation-related changes in kynurenine metabolism as a potential pathogenic factor in the development of a range of depressive symptoms, including deficits in cognition and memory. Additionally, preclinical work has demonstrated a number of mood-related depressive-like behaviors to be dependent on indoleamine 2,3-dioxygenase-1 (IDO1), the inflammation-induced rate-limiting enzyme of the kynurenine pathway. Here, we demonstrate in a mouse model, that peripheral administration of endotoxin induced a deficit in recognition memory. Mice deficient in IDO were protected from cognitive impairment. Furthermore, endotoxin-induced inflammation increased kynurenine metabolism within the perirhinal/entorhinal cortices, brain regions which have been implicated in recognition memory. A single peripheral injection of kynurenine, the metabolic product of IDO1, was sufficient to induce a deficit in recognition memory in both control and IDO null mice. Finally, kynurenine monooxygenase (KMO) deficient mice were also protected from inflammation-induced deficits on novel object recognition. These data implicate IDO-dependent neurotoxic kynurenine metabolism as a pathogenic factor for cognitive dysfunction in inflammation-induced depressive disorders and a potential novel target for the treatment of these disorders. Published by Elsevier Inc.

  18. Indoleamine 2,3-dioxygenase-dependent neurotoxic kynurenine metabolism mediates inflammation-induced deficit in recognition memory

    Science.gov (United States)

    Heisler, Jillian M.; O’Connor, Jason C.

    2015-01-01

    Cognitive dysfunction in depression is a prevalent and debilitating symptom that is poorly treated by the currently available pharmacotherapies. Research over the past decade has provided evidence for proinflammatory involvement in the neurobiology of depressive disorders and symptoms associated with these disorders, including aspects of memory dysfunction. Recent clinical studies implicate inflammation-related changes in kynurenine metabolism as a potential pathogenic factor in the development of a range of depressive symptoms, including deficits in cognition and memory. Additionally, preclinical work has demonstrated a number of mood-related depressive-like behaviors to be dependent on indoleamine 2,3-dioxygenase-1 (IDO1), the inflammation-induced rate-limiting enzyme of the kynurenine pathway. Here, we demonstrate in a mouse model, that peripheral administration of endotoxin induced a deficit in recognition memory. Mice deficient in IDO were protected from cognitive impairment. Furthermore, endotoxin-induced inflammation increased kynurenine metabolism within the perirhinal/entorhinal cortices, brain regions which have been implicated in recognition memory. A single peripheral injection of kynurenine, the metabolic product of IDO1, was sufficient to induce a deficit in recognition memory in both control and IDO null mice. Finally, kynurenine monooxygenase (KMO) deficient mice were also protected from inflammation-induced deficits on novel object recognition. These data implicate IDO-dependent neurotoxic kynurenine metabolism as a pathogenic factor for cognitive dysfunction in inflammation-induced depressive disorders and a potential novel target for the treatment of these disorders. PMID:26130057

  19. Neuroprotective effect of curcumin on okadaic acid induced memory impairment in mice.

    Science.gov (United States)

    Rajasekar, N; Dwivedi, Subhash; Tota, Santosh Kumar; Kamat, Pradeep Kumar; Hanif, Kashif; Nath, Chandishwar; Shukla, Rakesh

    2013-09-05

    Okadaic acid (OKA) has been observed to cause memory impairment in human subjects having seafood contaminated with dinoflagellate (Helicondria okadai). OKA induces tau hyperphosphorylation and oxidative stress leading to memory impairment as our previous study has shown. Curcumin a natural antioxidant has demonstrated neuroprotection in various models of neurodegeneration. However, the effect of curcumin has not been explored in OKA induced memory impairment. Therefore, present study evaluated the effect of curcumin on OKA (100ng, intracerebrally) induced memory impairment in male Swiss albino mice as evaluated in Morris water maze (MWM) and passive avoidance tests (PAT). OKA administration resulted in memory impairment with a decreased cerebral blood flow (CBF) (measured by laser doppler flowmetry), ATP level and increased mitochondrial (Ca(2+))i, neuroinflammation (increased TNF-α, IL-1β, COX-2 and GFAP), oxidative-nitrosative stress, increased Caspase-9 and cholinergic dysfunction (decreased AChE activity/expression and α7 nicotinic acetylcholine receptor expression) in cerebral cortex and hippocampus of mice brain. Oral administration of curcumin (50mg/kg) for 13 days significantly improved memory function in both MWM and PAT along with brain energy metabolism, CBF and cholinergic function. It decreased mitochondrial (Ca(2+))i, and ameliorated neuroinflammation and oxidative-nitrostative stress in different brain regions of OKA treated mice. Curcumin also inhibited astrocyte activation as evidenced by decreased GFAP expression. This neuroprotective effect of curcumin is due to its potent anti-oxidant action thus confirming previous studies. Therefore, use of curcumin should be encouraged in people consuming sea food (contaminated with dinoflagellates) to prevent cognitive impairment. © 2013 Elsevier B.V. All rights reserved.

  20. β1-Adrenoceptor in the Central Amygdala Is Required for Unconditioned Stimulus-Induced Drug Memory Reconsolidation

    Science.gov (United States)

    Zhu, Huiwen; Zhou, Yiming; Liu, Zhiyuan; Chen, Xi; Li, Yanqing; Liu, Xing; Ma, Lan

    2018-01-01

    Abstract Background Drug memories become labile and reconsolidated after retrieval by presentation of environmental cues (conditioned stimulus) or drugs (unconditioned stimulus). Whether conditioned stimulus and unconditioned stimulus retrieval trigger different memory reconsolidation processes is not clear. Methods Protein synthesis inhibitor or β-adrenergic receptor (β-AR) antagonist was systemically administrated or intra-central amygdala infused immediately after cocaine reexposure in cocaine-conditioned place preference or self-administration mice models. β-ARs were selectively knocked out in the central amygdala to further confirm the role of β-adrenergic receptor in cocaine reexposure-induced memory reconsolidation of cocaine-conditioned place preference. Results Cocaine reexposure triggered de novo protein synthesis dependent memory reconsolidation of cocaine-conditioned place preference. Cocaine-priming-induced reinstatement was also impaired with post cocaine retrieval manipulation, in contrast to the relapse behavior with post context retrieval manipulation. Cocaine retrieval, but not context retrieval, induced central amygdala activation. Protein synthesis inhibitor or β1-adrenergic receptor antagonist infused in the central amygdala after cocaine retrieval, but not context retrieval, inhibited memory reconsolidation and reinstatement. β1-adrenergic receptor knockout in the central amygdala suppressed cocaine retrieval-triggered memory reconsolidation and reinstatement of cocaine conditioned place preference. β1-adrenergic receptor antagonism after cocaine retrieval also impaired reconsolidation and reinstatement of cocaine self-administration. Conclusions Cocaine reward memory triggered by unconditioned stimulus retrieval is distinct from conditioned stimulus retrieval. Unconditioned stimulus retrieval induced reconsolidation of cocaine reward memory depends on β1-adrenergic signaling in the central amygdala. Post unconditioned stimulus

  1. Aqueous Extract of Black Maca (Lepidium meyenii) on Memory Impairment Induced by Ovariectomy in Mice.

    Science.gov (United States)

    Rubio, Julio; Qiong, Wang; Liu, Xinmin; Jiang, Zhen; Dang, Haixia; Chen, Shi-Lin; Gonzales, Gustavo F

    2011-01-01

    The present study aims to test two different doses of aqueous extract of black maca on learning and memory in ovariectomized (OVX) mice and their relation with malonalehyde (MDA), acetylcholinesterase (Ache) and monoamine oxidase (MAO) brain levels. Female mice were divided into five groups: (i) naive (control), (ii) sham, (iii) OVX mice and OVX mice treated with (iv) 0.50 g kg(-1) and (v) 2.00 g kg(-1) black maca. Mice were orally treated with distilled water or black maca during 35 days starting 7 days after surgery. Memory and learning were assessed using the water Morris maze (from day 23-27) and the step-down avoidance test (days 34 and 35). At the end of each treatment, mice were sacrificed by decapitation and brains were dissected out for MDA, Ache and MAO determinations. Black maca (0.5 and 2.0 g/kg) increased step-down latency when compared to OVX control mice. Black maca decreased MDA and Ache levels in OVX mice; whereas, no differences were observed in MAO levels. Finally, black maca improved experimental memory impairment induced by ovariectomy, due in part, by its antioxidant and Ache inhibitory activities.

  2. Rapid allergen-induced interleukin-17 and interferon-γ secretion by skin-resident memory CD8(+) T cells

    DEFF Research Database (Denmark)

    Schmidt, Jonas D; Ahlström, Malin G; Johansen, Jeanne D

    2017-01-01

    , the mechanisms whereby TRM cells induce rapid recall responses need further investigation. OBJECTIVES: To study whether contact allergens induce local and/or global memory, and to determine the mechanisms involved in memory responses in the skin. METHODS: To address these questions, we analysed responses......BACKGROUND: Skin-resident memory T (TRM ) cells are associated with immunological memory in the skin. Whether immunological memory responses to allergens in the skin are solely localized to previously allergen-exposed sites or are present globally in the skin is not clear. Furthermore......, long-lasting local memory and a weaker, temporary global immunological memory response to the allergen that is mediated by IL-17A-producing and IFN-γ-producing CD8(+) TRM cells....

  3. Involvement of nitrergic system of CA1in harmane induced learning and memory deficits.

    Science.gov (United States)

    Nasehi, Mohammad; Piri, Morteza; Abdollahian, Mojgan; Zarrindast, Mohammad Reza

    2013-01-17

    Harmane (HA) is a β-carboline alkaloid derived from the Peganum harmala plant which induces memory impairment. On the other hand some of the investigations showed that β-carboline alkaloids inhibit NO production. Thus, the aim of the present study was to investigate the role of nitrergic system of the dorsal hippocampus (CA1) in HA-induced amnesia in male adult mice. One-trial step-down passive avoidance and hole-board apparatuses were used for the assessment of memory retrieval and exploratory behaviors respectively. The data indicated that pre-training intraperitoneal (i.p.) administration of HA (12 and 16 mg/kg) decreased memory acquisition. Sole pre-training or pre-testing administration of L-NAME, a nitric oxide synthesis inhibitor (5, 10 and 15 μg/mice, intra-CA1) did not alter memory retrieval. On the other hand, pre-training (10 and 15 μg/mice, intra-CA1) and pre-testing (5, 10 μg/mice, intra-CA1) injections of L-NAME restored HA-induced amnesia (16 mg/kg, i.p.). Furthermore, neither sole pre-training nor pre-testing administration of l-arginine, a NO precursor (3, 6 and 9 μg/mice, intra-CA1), altered memory retrieval. In addition, pre-testing (6 and 9 μg/mice, intra-CA1), but not pre-training, injection of l-arginine increased HA-induced amnesia (16 mg/kg, i.p.). These results suggest that the nitrergic system of CA1 is involved in HA-induced amnesia. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. High energy hadron-induced errors in memory chips

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, R.J. [University of Colorado, Boulder, CO (United States)

    2001-09-01

    We have measured probabilities for proton, neutron and pion beams from accelerators to induce temporary or soft errors in a wide range of modern 16 Mb and 64 Mb dRAM memory chips, typical of those used in aircraft electronics. Relations among the cross sections for these particles are deduced, and failure rates for aircraft avionics due to cosmic rays are evaluated. Measurement of alpha pha particle yields from pions on aluminum, as a surrogate for silicon, indicate that these reaction products are the proximate cause of the charge deposition resulting in errors. Heavy ions can cause damage to solar panels and other components in satellites above the atmosphere, by the heavy ionization trails they leave. However, at the earth's surface or at aircraft altitude it is known that cosmic rays, other than heavy ions, can cause soft errors in memory circuit components. Soft errors are those confusions between ones and zeroes that cause wrong contents to be stored in the memory, but without causing permanent damage to the circuit. As modern aircraft rely increasingly upon computerized and automated systems, these soft errors are important threats to safety. Protons, neutrons and pions resulting from high energy cosmic ray bombardment of the atmosphere pervade our environment. These particles do not induce damage directly by their ionization loss, but rather by reactions in the materials of the microcircuits. We have measured many cross sections for soft error upsets (SEU) in a broad range of commercial 16 Mb and 64 Mb dRAMs with accelerator beams. Here we define {sigma} SEU = induced errors/number of sample bits x particles/cm{sup 2}. We compare {sigma} SEU to find relations among results for these beams, and relations to reaction cross sections in order to systematize effects. We have modelled cosmic ray effects upon the components we have studied. (Author)

  5. High energy hadron-induced errors in memory chips

    International Nuclear Information System (INIS)

    Peterson, R.J.

    2001-01-01

    We have measured probabilities for proton, neutron and pion beams from accelerators to induce temporary or soft errors in a wide range of modern 16 Mb and 64 Mb dRAM memory chips, typical of those used in aircraft electronics. Relations among the cross sections for these particles are deduced, and failure rates for aircraft avionics due to cosmic rays are evaluated. Measurement of alpha pha particle yields from pions on aluminum, as a surrogate for silicon, indicate that these reaction products are the proximate cause of the charge deposition resulting in errors. Heavy ions can cause damage to solar panels and other components in satellites above the atmosphere, by the heavy ionization trails they leave. However, at the earth's surface or at aircraft altitude it is known that cosmic rays, other than heavy ions, can cause soft errors in memory circuit components. Soft errors are those confusions between ones and zeroes that cause wrong contents to be stored in the memory, but without causing permanent damage to the circuit. As modern aircraft rely increasingly upon computerized and automated systems, these soft errors are important threats to safety. Protons, neutrons and pions resulting from high energy cosmic ray bombardment of the atmosphere pervade our environment. These particles do not induce damage directly by their ionization loss, but rather by reactions in the materials of the microcircuits. We have measured many cross sections for soft error upsets (SEU) in a broad range of commercial 16 Mb and 64 Mb dRAMs with accelerator beams. Here we define σ SEU = induced errors/number of sample bits x particles/cm 2 . We compare σ SEU to find relations among results for these beams, and relations to reaction cross sections in order to systematize effects. We have modelled cosmic ray effects upon the components we have studied. (Author)

  6. Postretrieval new learning does not reliably induce human memory updating via reconsolidation.

    Science.gov (United States)

    Hardwicke, Tom E; Taqi, Mahdi; Shanks, David R

    2016-05-10

    Reconsolidation theory proposes that retrieval can destabilize an existing memory trace, opening a time-dependent window during which that trace is amenable to modification. Support for the theory is largely drawn from nonhuman animal studies that use invasive pharmacological or electroconvulsive interventions to disrupt a putative postretrieval restabilization ("reconsolidation") process. In human reconsolidation studies, however, it is often claimed that postretrieval new learning can be used as a means of "updating" or "rewriting" existing memory traces. This proposal warrants close scrutiny because the ability to modify information stored in the memory system has profound theoretical, clinical, and ethical implications. The present study aimed to replicate and extend a prominent 3-day motor-sequence learning study [Walker MP, Brakefield T, Hobson JA, Stickgold R (2003) Nature 425(6958):616-620] that is widely cited as a convincing demonstration of human reconsolidation. However, in four direct replication attempts (n = 64), we did not observe the critical impairment effect that has previously been taken to indicate disruption of an existing motor memory trace. In three additional conceptual replications (n = 48), we explored the broader validity of reconsolidation-updating theory by using a declarative recall task and sequences similar to phone numbers or computer passwords. Rather than inducing vulnerability to interference, memory retrieval appeared to aid the preservation of existing sequence knowledge relative to a no-retrieval control group. These findings suggest that memory retrieval followed by new learning does not reliably induce human memory updating via reconsolidation.

  7. Disrupting the memory of places induced by drugs of abuse weakens motivational withdrawal in a context-dependent manner.

    Science.gov (United States)

    Taubenfeld, Stephen M; Muravieva, Elizaveta V; Garcia-Osta, Ana; Alberini, Cristina M

    2010-07-06

    Addicts repeatedly relapse to drug seeking even after years of abstinence, and this behavior is frequently induced by the recall of memories of the rewarding effects of the drug. Established memories, including those induced by drugs of abuse, can become transiently fragile if reactivated, and during this labile phase, known as reconsolidation, can be persistently disrupted. Here we show that, in rats, a morphine-induced place preference (mCPP) memory is linked to context-dependent withdrawal as disrupting the reconsolidation of the memory leads to a significant reduction of withdrawal evoked in the same context. Moreover, the hippocampus plays a critical role in linking the place preference memory with the context-conditioned withdrawal, as disrupting hippocampal protein synthesis and cAMP-dependent-protein kinase A after the reactivation of mCPP significantly weakens the withdrawal. Hence, targeting memories induced by drugs may represent an important strategy for attenuating context-conditioned withdrawal and therefore subsequent relapse in opiate addicts.

  8. Peripheral and central CB1 cannabinoid receptors control stress-induced impairment of memory consolidation.

    Science.gov (United States)

    Busquets-Garcia, Arnau; Gomis-González, Maria; Srivastava, Raj Kamal; Cutando, Laura; Ortega-Alvaro, Antonio; Ruehle, Sabine; Remmers, Floortje; Bindila, Laura; Bellocchio, Luigi; Marsicano, Giovanni; Lutz, Beat; Maldonado, Rafael; Ozaita, Andrés

    2016-08-30

    Stressful events can generate emotional memories linked to the traumatic incident, but they also can impair the formation of nonemotional memories. Although the impact of stress on emotional memories is well studied, much less is known about the influence of the emotional state on the formation of nonemotional memories. We used the novel object-recognition task as a model of nonemotional memory in mice to investigate the underlying mechanism of the deleterious effect of stress on memory consolidation. Systemic, hippocampal, and peripheral blockade of cannabinoid type-1 (CB1) receptors abolished the stress-induced memory impairment. Genetic deletion and rescue of CB1 receptors in specific cell types revealed that the CB1 receptor population specifically in dopamine β-hydroxylase (DBH)-expressing cells is both necessary and sufficient for stress-induced impairment of memory consolidation, but CB1 receptors present in other neuronal populations are not involved. Strikingly, pharmacological manipulations in mice expressing CB1 receptors exclusively in DBH(+) cells revealed that both hippocampal and peripheral receptors mediate the impact of stress on memory consolidation. Thus, CB1 receptors on adrenergic and noradrenergic cells provide previously unrecognized cross-talk between central and peripheral mechanisms in the stress-dependent regulation of nonemotional memory consolidation, suggesting new potential avenues for the treatment of cognitive aspects on stress-related disorders.

  9. Blurring of emotional and non-emotional memories by taxing working memory during recall.

    Science.gov (United States)

    van den Hout, Marcel A; Eidhof, Marloes B; Verboom, Jesse; Littel, Marianne; Engelhard, Iris M

    2014-01-01

    Memories that are recalled while working memory (WM) is taxed, e.g., by making eye movements (EM), become blurred during the recall + EM and later recall, without EM. This may help to explain the effects of Eye Movement and Desensitisation and Reprocessing (EMDR) in the treatment of post-traumatic stress disorder (PTSD) in which patients make EM during trauma recall. Earlier experimental studies on recall + EM have focused on emotional memories. WM theory suggests that recall + EM is superior to recall only but is silent about effects of memory emotionality. Based on the emotion and memory literature, we examined whether recall + EM has superior effects in blurring emotional memories relative to neutral memories. Healthy volunteers recalled negative or neutral memories, matched for vividness, while visually tracking a dot that moved horizontally ("recall + EM") or remained stationary ("recall only"). Compared to a pre-test, a post-test (without concentrating on the dot) replicated earlier findings: negative memories are rated as less vivid after "recall + EM" but not after "recall only". This was not found for neutral memories. Emotional memories are more taxing than neutral memories, which may explain the findings. Alternatively, transient arousal induced by recall of aversive memories may promote reconsolidation of the blurred memory image that is provoked by EM.

  10. Orientation dependence of stress-induced martensite formation during nanoindentation in NiTi shape memory alloys

    International Nuclear Information System (INIS)

    Laplanche, G.; Pfetzing-Micklich, J.; Eggeler, G.

    2014-01-01

    In the present work we used nanoindentation with a spherical indenter tip to study the formation of stress-induced martensite in NiTi shape memory alloys. Prior to nanoindentation, orientation imaging was performed to select austenite grains with specific crystallographic orientations, including the principal crystallographic directions [0 0 1], [1 0 1] and [1 1 1]. We studied a material where stress-induced martensite is stable at room temperature and found surface patterns with four-, two- and threefold symmetries for the [0 0 1], [1 0 1] and [1 1 1] crystallographic indentation directions, respectively. Atomic force microscopy investigations of the topography showed that the surface patterns were associated with sink-ins. The crystallographic sink-in patterns disappeared during heating, which proved their martensitic origin. Our results provide clear experimental evidence which shows that the crystallographic anisotropy of nanoindentation is governed by the crystallographic anisotropy of the stress-induced formation of martensite

  11. Glucocorticoid effects on object recognition memory require training-associated emotional arousal.

    Science.gov (United States)

    Okuda, Shoki; Roozendaal, Benno; McGaugh, James L

    2004-01-20

    Considerable evidence implicates glucocorticoid hormones in the regulation of memory consolidation and memory retrieval. The present experiments investigated whether the influence of these hormones on memory depends on the level of emotional arousal induced by the training experience. We investigated this issue in male Sprague-Dawley rats by examining the effects of immediate posttraining systemic injections of the glucocorticoid corticosterone on object recognition memory under two conditions that differed in their training-associated emotional arousal. In rats that were not previously habituated to the experimental context, corticosterone (0.3, 1.0, or 3.0 mg/kg, s.c.) administered immediately after a 3-min training trial enhanced 24-hr retention performance in an inverted-U shaped dose-response relationship. In contrast, corticosterone did not affect 24-hr retention of rats that received extensive prior habituation to the experimental context and, thus, had decreased novelty-induced emotional arousal during training. Additionally, immediate posttraining administration of corticosterone to nonhabituated rats, in doses that enhanced 24-hr retention, impaired object recognition performance at a 1-hr retention interval whereas corticosterone administered after training to well-habituated rats did not impair 1-hr retention. Thus, the present findings suggest that training-induced emotional arousal may be essential for glucocorticoid effects on object recognition memory.

  12. The Role of Hippocampal 5HT3 Receptors in Harmaline-Induced Memory Deficit

    Directory of Open Access Journals (Sweden)

    Mohammad Nasehi

    2015-07-01

    Full Text Available Introduction: The plethora of studies indicated that there is a cross talk relationship between harmaline and serotonergic (5-HT system on cognitive and non-cognitive behaviors. Thus, the purpose of this study is to assess the effects of hippocampal 5-HT4 receptor on memory acquisition deficit induced by harmaline.  Methods: Harmaline was injected peritoneally, while 5-HT4 receptor agonist (RS67333 and antagonist (RS23597-190 were injected intra-hippocampal. A single-trial step-down passive avoidance, open field and tail flick tasks were used for measurement of memory, locomotor activity and pain responses, respectively.  Results: The data revealed that pre-training injection of higher dose of harmaline (1 mg/kg, RS67333 (0.5 ng/mouse and RS23597-190 (0.5 ng/mouse decreased memory acquisition process in the adult mice. Moreover, concurrent pre-training administration of subthreshold dose of RS67333 (0.005 ng/mouse or RS23597-190 (0.005 ng/mouse with subthreshold dose of harmaline (0.5 mg/kg, i.p. intensify impairment of memory acquisition. All above interventions did not change locomotion and tail flick behaviors.  Discussion: The results demonstrated that the synergistic effect between both hippocampal 5-HT4 receptor agonist and antagonist with impairment of memory acquisition induced by harmaline, indicating a modulatory effect for hippocampal 5HT4 receptor on Harmaline induced amnesia.

  13. Virtual peer-delivered memory intervention: a single-case experimental design in an adolescent with chronic memory impairment.

    Science.gov (United States)

    Cooper, Janine M; Lockett, Stephen; McIlroy, Alissandra; Gonzalez, Linda

    2018-01-01

    Children and adolescents with chronic memory impairment may develop coping strategies that enable functioning, yet these often remain undetectable using traditional psychometric measures. Personalized intervention studies that promote the use of such strategies designed specifically for use by this young cohort are scarce. To investigate the effect of a novel virtual reality peer-delivered memory intervention on the everyday functioning and well-being of SE, a 17-year-old female with a history of chronic verbal memory issues, impaired autobiographical event recall and elevated mood symptoms. A single-case ABA experimental design study was used to assess change. Following initial baseline assessment using objective neuropsychological and subjective functional questionnaires and intervention training, case SE used the intervention daily for 3 weeks before repeating key outcome measures. Using non-overlap of all pairs and qualitative feedback analysis, the results revealed a significant increase in event recall and self-reported positive changes to levels of everyday functioning. Supporting autobiographical event recall and prospective memory via a virtual peer-delivered intervention may lead to reduction in cognitive load, and benefit overall well-being and everyday functioning.

  14. Effects of alcohol-induced working memory decline on alcohol consumption and adverse consequences of use.

    Science.gov (United States)

    Lechner, William V; Day, Anne M; Metrik, Jane; Leventhal, Adam M; Kahler, Christopher W

    2016-01-01

    Alcohol use appears to decrease executive function acutely in a dose-dependent manner, and lower baseline executive function appears to contribute to problematic alcohol use. However, no studies, to our knowledge, have examined the relationship between individual differences in working memory (a subcomponent of executive function) after alcohol consumption and drinking behaviors and consequences. The current study assessed the relationship between drinking behavior, alcohol-related consequences, and alcohol-induced changes in working memory (as assessed by Trail Making Test-B). Participants recruited from the community (n = 41), 57.3 % male, mean age 39.2, took part in a three-session, within-subjects, repeated-measures design. Participants were administered a placebo, 0.4 g/kg, or 0.8 g/kg dose of alcohol. Working memory, past 30-day alcohol consumption, and consequences of alcohol use were measured at baseline; working memory was measured again after each beverage administration. Poorer working memory after alcohol administration (controlling for baseline working memory) was significantly associated with a greater number of drinks consumed per drinking day. Additionally, we observed a significant indirect relationship between the degree of alcohol-induced working memory decline and adverse consequences of alcohol use, which was mediated through greater average drinks per drinking day. It is possible that greater individual susceptibility to alcohol-induced working memory decline may limit one's ability to moderate alcohol consumption as evidenced by greater drinks per drinking day and that this results in more adverse consequences of alcohol use.

  15. Filing false vice reports: Distinguishing true from false allegations of rape

    NARCIS (Netherlands)

    de Zutter, A.; Horselenberg, R.; van Koppen, P.J.

    2017-01-01

    False allegations constitute a problem since they may cause harm. To study the difference between true and false allegations we used a quasi-experimental approach. In the control condition likely true allegations were retrieved from criminal files. The victims, all female, were between the ages of

  16. A silicon-nanowire memory driven by optical gradient force induced bistability

    Energy Technology Data Exchange (ETDEWEB)

    Dong, B. [School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research), Singapore 117685 (Singapore); Cai, H., E-mail: caih@ime.a-star.edu.sg; Gu, Y. D.; Kwong, D. L. [Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research), Singapore 117685 (Singapore); Chin, L. K.; Ng, G. I.; Ser, W. [School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Huang, J. G. [School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research), Singapore 117685 (Singapore); School of Mechanical Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Yang, Z. C. [School of Electronics Engineering and Computer Science, Peking University, Beijing 100871 (China); Liu, A. Q., E-mail: eaqliu@ntu.edu.sg [School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore); School of Electronics Engineering and Computer Science, Peking University, Beijing 100871 (China)

    2015-12-28

    In this paper, a bistable optical-driven silicon-nanowire memory is demonstrated, which employs ring resonator to generate optical gradient force over a doubly clamped silicon-nanowire. Two stable deformation positions of a doubly clamped silicon-nanowire represent two memory states (“0” and “1”) and can be set/reset by modulating the light intensity (<3 mW) based on the optical force induced bistability. The time response of the optical-driven memory is less than 250 ns. It has applications in the fields of all optical communication, quantum computing, and optomechanical circuits.

  17. Tokishakuyakusan ameliorates spatial memory deficits induced by ovariectomy combined with β-amyloid in rats

    Directory of Open Access Journals (Sweden)

    Nobuaki Egashira

    2018-03-01

    Full Text Available Previously, we reported that ovariectomy (OVX combined with β-amyloid peptide (Aβ impaired spatial memory by decreasing extracellular acetylcholine (ACh levels in the dorsal hippocampus. Here, we investigated the effect of tokishakuyakusan (TSS, a Kampo medicine, on the impairment of spatial memory induced by OVX combined with Aβ in rats. Repeated administration of TSS (300 mg/kg, p.o. significantly decreased the number of errors in the eight-arm radial maze test. Though TSS had no effect on extracellular ACh levels at baseline, TSS significantly increased extracellular ACh levels in the dorsal hippocampus. These results suggest that TSS improves the impairment of spatial memory induced by OVX combined with Aβ by (at least in part increasing extracellular ACh levels in the dorsal hippocampus. Keywords: Tokishakuyakusan, Ovariectomy, β-Amyloid, Memory, Acetylcholine

  18. To forget or not to forget: mnemonic “renunciation” effect and the subjective evaluation of the truth of autobiographical memories

    Directory of Open Access Journals (Sweden)

    Nourkova V. V.

    2015-08-01

    Full Text Available Identifying patterns of influence deliberate lie on deferred confidence of reliability of autobiographical memories is current problem for legal psychology. We reviewed the variability of autobiographical memories in the context of legal practice. In addition, we conducted the experimental field study of the dynamics of subjective assessments of the reliability of memories. It was found that truthful confirmation and false refutation of reliable last episodes, as well as after a truthful refutation and false confirmation of unreliable last episodes lead to regular changes in the subjective assessment of the reliability. The mnemonic "renunciation effect" is that a false refutation of a reliable episode leads to its forgetting and a truthful refutation of an unreliable episode leads to its erroneous inclusion in autobiographical memory.

  19. Nuclear data relevant to single event upsets in semiconductor memories induced by cosmic-ray neutrons and protons

    International Nuclear Information System (INIS)

    Watanabe, Yukinobu

    2008-01-01

    The role of nuclear data is examined in the study of single event upset (SEU) phenomena in semiconductor memories caused by cosmic-ray neutrons and protons. Neutron and proton SEU cross sections are calculated with a simplified semi-empirical model using experimental heavy-ion SEU cross-sections and a dedicated database of neutron and proton induced reactions on 28 Si. Some impacts of the nuclear reaction data on SEU simulation are analyzed by investigating relative contribution of secondary ions and neutron elastic scattering to SEU and influence of simultaneous multiple ions emission on SEU. (author)

  20. Preventive and therapeutic effect of treadmill running on chronic stress-induced memory deficit in rats.

    Science.gov (United States)

    Radahmadi, Maryam; Alaei, Hojjatallah; Sharifi, Mohammad Reza; Hosseini, Nasrin

    2015-04-01

    Previous results indicated that stress impairs learning and memory. In this research, the effects of preventive, therapeutic and regular continually running activity on chronic stress-induced memory deficit in rats were investigated. 70 male rats were randomly divided into seven groups as follows: Control, Sham, Stress-Rest, Rest-Stress, Stress-Exercise, Exercise-Stress and Exercise-Stress & Exercise groups. Chronic restraint stress was applied 6 h/day for 21days and treadmill running 1 h/day. Memory function was evaluated by the passive avoidance test. The results revealed that running activities had therapeutic effect on mid and long-term memory deficit and preventive effects on short and mid-term memory deficit in stressed rats. Regular continually running activity improved mid and long-term memory compared to Exercise-Stress group. The beneficial effects of exercise were time-dependent in stress conditions. Finally, data corresponded to the possibility that treadmill running had a more important role on treatment rather than on prevention on memory impairment induced by stress. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. The Effects of Loranthus parasiticus on Scopolamine-Induced Memory Impairment in Mice

    Directory of Open Access Journals (Sweden)

    Jin Bae Weon

    2014-01-01

    Full Text Available This study is undertaken to evaluate cognitive enhancing effect and neuroprotective effect of Loranthus parasiticus. Cognitive enhancing effect of Loranthus parasiticus was investigated on scopolamine-induced amnesia model in Morris water maze test and passive avoidance test. We also examined the neuroprotective effect on glutamate-induced cell death in HT22 cells by MTT assay. These results of Morris water maze test and passive avoidance test indicated that 10 and 50 mg/kg of Loranthus parasiticus reversed scopolamine-induced memory deficits. Loranthus parasiticus also protected against glutamate-induced cytotoxicity in HT22 cells. As a result of in vitro test for elucidating possible mechanism, Loranthus parasiticus inhibited AChE activity, ROS production, and Ca2+ accumulation. Loranthus parasiticus showed memory enhancing effect and neuroprotective effect and these effects may be related to inhibition of AChE activity, ROS level, and Ca2+ influx.

  2. Effects of scallop shell extract on scopolamine-induced memory impairment and MK801-induced locomotor activity

    OpenAIRE

    HASEGAWA, Yasushi; INOUE, Tatsuro; KAWAMINAMI, Satoshi; FUJITA, Miho

    2016-01-01

    ObjectiveTo evaluate the neuroprotective effects of the organic components of scallop shells (scallop shell extract) on memory impairment and locomotor activity induced by scopolamine or 5-methyl-10,11-dihydro-5H-dibenzo (a,d) cyclohepten-5,10-imine (MK801).MethodsEffect of the scallop shell extract on memory impairment and locomotor activity was investigated using the Y-maze test, the Morris water maze test, and the open field test.ResultsScallop shell extract significantly reduced scopolami...

  3. Cognitive load and task condition in event- and time-based prospective memory: an experimental investigation.

    Science.gov (United States)

    Khan, Azizuddin; Sharma, Narendra K; Dixit, Shikha

    2008-09-01

    Prospective memory is memory for the realization of delayed intention. Researchers distinguish 2 kinds of prospective memory: event- and time-based (G. O. Einstein & M. A. McDaniel, 1990). Taking that distinction into account, the present authors explored participants' comparative performance under event- and time-based tasks. In an experimental study of 80 participants, the authors investigated the roles of cognitive load and task condition in prospective memory. Cognitive load (low vs. high) and task condition (event- vs. time-based task) were the independent variables. Accuracy in prospective memory was the dependent variable. Results showed significant differential effects under event- and time-based tasks. However, the effect of cognitive load was more detrimental in time-based prospective memory. Results also revealed that time monitoring is critical in successful performance of time estimation and so in time-based prospective memory. Similarly, participants' better performance on the event-based prospective memory task showed that they acted on the basis of environment cues. Event-based prospective memory was environmentally cued; time-based prospective memory required self-initiation.

  4. Conceptual fluency at test shifts recognition response bias in Alzheimer's disease: implications for increased false recognition.

    Science.gov (United States)

    Gold, Carl A; Marchant, Natalie L; Koutstaal, Wilma; Schacter, Daniel L; Budson, Andrew E

    2007-09-20

    The presence or absence of conceptual information in pictorial stimuli may explain the mixed findings of previous studies of false recognition in patients with mild Alzheimer's disease (AD). To test this hypothesis, 48 patients with AD were compared to 48 healthy older adults on a recognition task first described by Koutstaal et al. [Koutstaal, W., Reddy, C., Jackson, E. M., Prince, S., Cendan, D. L., & Schacter D. L. (2003). False recognition of abstract versus common objects in older and younger adults: Testing the semantic categorization account. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29, 499-510]. Participants studied and were tested on their memory for categorized ambiguous pictures of common objects. The presence of conceptual information at study and/or test was manipulated by providing or withholding disambiguating semantic labels. Analyses focused on testing two competing theories. The semantic encoding hypothesis, which posits that the inter-item perceptual details are not encoded by AD patients when conceptual information is present in the stimuli, was not supported by the findings. In contrast, the conceptual fluency hypothesis was supported. Enhanced conceptual fluency at test dramatically shifted AD patients to a more liberal response bias, raising their false recognition. These results suggest that patients with AD rely on the fluency of test items in making recognition memory decisions. We speculate that AD patients' over reliance upon fluency may be attributable to (1) dysfunction of the hippocampus, disrupting recollection, and/or (2) dysfunction of prefrontal cortex, disrupting post-retrieval processes.

  5. Fuzzy-trace theory: dual processes in memory, reasoning, and cognitive neuroscience.

    Science.gov (United States)

    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

  6. Ameliorating Effects of Ethanol Extract of Fructus mume on Scopolamine-Induced Memory Impairment in Mice

    Directory of Open Access Journals (Sweden)

    Min-Soo Kim

    2015-01-01

    Full Text Available We previously reported that Fructus mume (F. mume extract shows protective effects on memory impairments and anti-inflammatory effects induced by chronic cerebral hypoperfusion. Neurodegeneration of basal cholinergic neurons is also observed in the brain with chronic cerebral hypoperfusion. Therefore, the present study was conducted to examine whether F. mume extracts enhance cognitive function via the action of cholinergic neuron using a scopolamine-induced animal model of memory impairments. F. mume (50, 100, or 200 mg/kg was administered to C57BL/6 mice for 14 days (days 1–14 and memory impairment was induced by scopolamine (1 mg/kg, a muscarinic receptor antagonist for 7 days (days 8–14. Spatial memory was assessed using Morris water maze and hippocampal level of acetylcholinesterase (AChE and choline acetyltransferase (ChAT was examined by ELISA and immunoblotting. Mice that received scopolamine alone showed impairments in acquisition and retention in Morris water maze task and increased activity of AChE in the hippocampus. Mice that received F. mume and scopolamine showed no scopolamine-induced memory impairment and increased activity of AChE. In addition, treatments of F. mume increased ChAT expression in the hippocampus. These results indicated that F. mume might enhance cognitive function via action of cholinergic neurons.

  7. Pridopidine Reverses Phencyclidine-Induced Memory Impairment.

    Science.gov (United States)

    Sahlholm, Kristoffer; Valle-León, Marta; Fernández-Dueñas, Víctor; Ciruela, Francisco

    2018-01-01

    Pridopidine is in clinical trials for Huntington's disease treatment. Originally developed as a dopamine D 2 receptor (D 2 R) ligand, pridopidine displays about 100-fold higher affinity for the sigma-1 receptor (sigma-1R). Interestingly, pridopidine slows disease progression and improves motor function in Huntington's disease model mice and, in preliminarily reports, Huntington's disease patients. The present study examined the anti-amnesic potential of pridopidine. Thus, memory impairment was produced in mice by administration of phencyclidine (PCP, 10 mg/kg/day) for 10 days, followed by 14 days' treatment with pridopidine (6 mg/kg/day), or saline. Finally, novel object recognition performance was assessed in the animals. Mice receiving PCP and saline exhibited deficits in novel object recognition, as expected, while pridopidine treatment counteracted PCP-induced memory impairment. The effect of pridopidine was attenuated by co-administration of the sigma receptor antagonist, NE-100 (10 mg/kg). Our results suggest that pridopidine exerts anti-amnesic and potentially neuroprotective actions. These data provide new insights into the therapeutic potential of pridopidine as a pro-cognitive drug.

  8. Experimental and modelling studies of the shape memory properties of amorphous polymer network composites

    International Nuclear Information System (INIS)

    Arrieta, J S; Diani, J; Gilormini, P

    2014-01-01

    Shape memory polymer composites (SMPCs) have become an important way to leverage improvements in the development of applications featuring shape memory polymers (SMPs). In this study, an amorphous SMP matrix has been filled with different types of reinforcements. An experimental set of results is presented and then compared to three-dimensional (3D) finite-element simulations. Thermomechanical shape memory cycles were performed in uniaxial tension. The fillers effect was studied in stress-free and constrained-strain recoveries. Experimental observations indicate complete shape recovery and put in evidence the increased sensitivity of constrained length stress recoveries to the heating ramp on the tested composites. The simulations reproduced a simplified periodic reinforced composite and used a model for the matrix material that has been previously tested on regular SMPs. The latter combines viscoelasticity at finite strain and time-temperature superposition. The simulations easily allow representation of the recovery properties of a reinforced SMP. (paper)

  9. Cognitive-Enhancing Effect of Dianthus superbus var. Longicalycinus on Scopolamine-Induced Memory Impairment in Mice.

    Science.gov (United States)

    Weon, Jin Bae; Jung, Youn Sik; Ma, Choong Je

    2016-05-01

    Dianthus superbus (D. superbus) is a traditional crude drug used for the treatment of urethritis, carbuncles and carcinomas. The objective of this study was to confirm the cognitive enhancing effect of D. superbus in memory impairment induced mice and to elucidate the possible potential mechanism. Effect of D. superbus on scopolamine induced memory impairment on mice was evaluated using the Morris water maze and passive avoidance tests. We also investigated acetylcholinesterase (AChE) activity and brain-derived neurotropic factor (BDNF) expression in scopolamine-induced mice. HPLC-DAD analysis was performed to identify active compounds in D. superbus. The results revealed that D. superbus attenuated the learning and memory impairment induced by scopolamine. D. superbus also inhibited AChE levels in the hippocampi of the scopolamine-injected mice. Moreover, D. superbus increased BDNF expression in the hippocampus. Eight compounds were identified using HPLC-DAD analysis. The content of 4-hydroxyphenyl acetic acid was higher than contents of other compounds. These results indicated that D. superbus improved memory functioning accompanied by inhibition of AChE and upregulation of BDNF, suggesting that D. superbus may be a useful therapeutic agent for the prevention or treatment of Alzheimer's disease.

  10. Correcting false information in memory: manipulating the strength of misinformation encoding and its retraction.

    Science.gov (United States)

    Ecker, Ullrich K H; Lewandowsky, Stephan; Swire, Briony; Chang, Darren

    2011-06-01

    Information that is presumed to be true at encoding but later on turns out to be false (i.e., misinformation) often continues to influence memory and reasoning. In the present study, we investigated how the strength of encoding and the strength of a later retraction of the misinformation affect this continued influence effect. Participants read an event report containing misinformation and a subsequent correction. Encoding strength of the misinformation and correction were orthogonally manipulated either via repetition (Experiment 1) or by imposing a cognitive load during reading (Experiment 2). Results suggest that stronger retractions are effective in reducing the continued influence effects associated with strong misinformation encoding, but that even strong retractions fail to eliminate continued influence effects associated with relatively weak encoding. We present a simple computational model based on random sampling that captures this effect pattern, and conclude that the continued influence effect seems to defy most attempts to eliminate it.

  11. Dissociating the two faces of selective memory retrieval.

    Science.gov (United States)

    Dobler, Ina M; Bäuml, Karl-Heinz T

    2012-07-01

    Research in the past four decades has repeatedly shown that selective retrieval of some (non-target) memories can impair subsequent retrieval of other (target) information, a finding known as retrieval-induced forgetting. More recently, however, there is evidence that selective retrieval can both impair and enhance recall of related memories (K-H. T. Bäuml & Samenieh, 2010). To identify possible experimental dissociations between the detrimental and the beneficial effects of memory retrieval, we examined retrieval dynamics in listwise directed forgetting, varying the delay between preceding non-target and subsequent target recall. When target recall immediately followed non-target recall, we replicated the prior work and found detrimental effects of memory retrieval on to-be-remembered items but beneficial effects on to-be-forgotten items. In contrast, when a delay was introduced between non-target and target recall, the detrimental effects were present but the beneficial effects were absent. The results demonstrate a first experimental dissociation between the two effects of memory retrieval. They are consistent with a recent two-factor account of the two faces of selective memory retrieval.

  12. An Experimental Analysis of Memory Processing

    Science.gov (United States)

    Wright, Anthony A.

    2007-01-01

    Rhesus monkeys were trained and tested in visual and auditory list-memory tasks with sequences of four travel pictures or four natural/environmental sounds followed by single test items. Acquisitions of the visual list-memory task are presented. Visual recency (last item) memory diminished with retention delay, and primacy (first item) memory…

  13. Aqueous Extract of Black Maca (Lepidium meyenii on Memory Impairment Induced by Ovariectomy in Mice

    Directory of Open Access Journals (Sweden)

    Julio Rubio

    2011-01-01

    Full Text Available The present study aims to test two different doses of aqueous extract of black maca on learning and memory in ovariectomized (OVX mice and their relation with malonalehyde (MDA, acetylcholinesterase (Ache and monoamine oxidase (MAO brain levels. Female mice were divided into five groups: (i naive (control, (ii sham, (iii OVX mice and OVX mice treated with (iv 0.50 g kg−1 and (v 2.00 g kg−1 black maca. Mice were orally treated with distilled water or black maca during 35 days starting 7 days after surgery. Memory and learning were assessed using the water Morris maze (from day 23–27 and the step-down avoidance test (days 34 and 35. At the end of each treatment, mice were sacrificed by decapitation and brains were dissected out for MDA, Ache and MAO determinations. Black maca (0.5 and 2.0 g/kg increased step-down latency when compared to OVX control mice. Black maca decreased MDA and Ache levels in OVX mice; whereas, no differences were observed in MAO levels. Finally, black maca improved experimental memory impairment induced by ovariectomy, due in part, by its antioxidant and Ache inhibitory activities.

  14. Alcohol-Induced Memory Blackouts as an Indicator of Injury Risk among College Drinkers

    Science.gov (United States)

    Mundt, Marlon P.; Zakletskaia, Larissa I.; Brown, David D.; Fleming, Michael F.

    2011-01-01

    Objective An alcohol-induced memory blackout represents an amnesia to recall events but does not involve a loss of consciousness. Memory blackouts are a common occurrence among college drinkers, but it is not clear if a history of memory blackouts is predictive of future alcohol-related injury above and beyond the risk associated with heavy drinking episodes. This analysis sought to determine if baseline memory blackouts can prospectively identify college students with alcohol-related injury in the next 24 months after controlling for heavy drinking days. Methods Data were analyzed from the College Health Intervention Project Study (CHIPS), a randomized controlled trial of screening and brief physician intervention for problem alcohol use among 796 undergraduate and 158 graduate students at four university sites in the US and one in Canada, conducted from 2004 to 2009. Multivariate analyses used generalized estimating equations (GEE) with the logit link. Results The overall 24-month alcohol-related injury rate was 25.6%, with no significant difference between males and females (p=.51). Alcohol-induced memory blackouts at baseline exhibited a significant dose-response on odds of alcohol-related injury during follow-up, increasing from 1.57 (95% CI: 1.13–2.19) for subjects reporting 1–2 memory blackouts at baseline to 2.64 (95% CI: 1.65–4.21) for students acknowledging 6+ memory blackouts at baseline. The link between memory blackouts and injury was mediated by younger age, prior alcohol-related injury, heavy drinking, and sensation-seeking disposition. Conclusions Memory blackouts are a significant predictor of future alcohol-related injury among college drinkers after adjusting for heavy drinking episodes. PMID:21708813

  15. Hypothalamic-pituitary-adrenal axis reactivity to psychological stress and memory in middle-aged women: high responders exhibit enhanced declarative memory performance.

    Science.gov (United States)

    Domes, G; Heinrichs, M; Reichwald, U; Hautzinger, M

    2002-10-01

    According to recent studies, elevated cortisol levels are associated with impaired declarative memory performance. This specific effect of cortisol has been shown in several studies using pharmacological doses of cortisol. The present study was designed to determine the effects of endogenously stimulated cortisol secretion on memory performance in healthy middle-aged women. For psychological stress challenging, we employed the Trier Social Stress Test (TSST). Subjects were assigned to either the TSST or a non-stressful control condition. Declarative and non-declarative memory performance was measured by a combined priming-free-recall-task. No significant group differences were found for memory performance. Post hoc analyses of variance indicated that regardless of experimental condition the subjects with remarkably high cortisol increase in response to the experimental procedure (high responders) showed increased memory performance in the declarative task compared to subjects with low cortisol response (low responders). The results suggest that stress-induced cortisol failed to impair memory performance. The results are discussed with respect to gender-specific effects and modulatory effects of the sympathetic nervous system and psychological variables. Copyright 2002 Elsevier Science Ltd.

  16. Isoflurane-induced spatial memory impairment in mice is prevented by the acetylcholinesterase inhibitor donepezil.

    Directory of Open Access Journals (Sweden)

    Diansan Su

    Full Text Available Although many studies have shown that isoflurane exposure impairs spatial memory in aged animals, there are no clinical treatments available to prevent this memory deficit. The anticholinergic properties of volatile anesthetics are a biologically plausible cause of cognitive dysfunction in elderly subjects. We hypothesized that pretreatment with the acetylcholinesterase inhibitor donepezil, which has been approved by the Food and Drug Administration (FDA for the treatment of Alzheimer's disease, prevents isoflurane-induced spatial memory impairment in aged mice. In present study, eighteen-month-old mice were administered donepezil (5 mg/kg or an equal volume of saline by oral gavage with a feeding needle for four weeks. Then the mice were exposed to isoflurane (1.2% for six hours. Two weeks later, mice were subjected to the Morris water maze to examine the impairment of spatial memory after exposure to isoflurane. After the behavioral test, the mice were sacrificed, and the protein expression level of acetylcholinesterase (AChE, choline acetylase (ChAT and α7 nicotinic receptor (α7-nAChR were measured in the brain. Each group consisted of 12 mice. We found that isoflurane exposure for six hours impaired the spatial memory of the mice. Compared with the control group, isoflurane exposure dramatically decreased the protein level of ChAT, but not AChE or α7-nAChR. Donepezil prevented isoflurane-induced spatial memory impairments and increased ChAT levels, which were downregulated by isoflurane. In conclusions, pretreatment with the AChE inhibitor donepezil prevented isoflurane-induced spatial memory impairment in aged mice. The mechanism was associated with the upregulation of ChAT, which was decreased by isoflurane.

  17. Glucose-induced metabolic memory in Schwann cells: prevention by PPAR agonists.

    Science.gov (United States)

    Kim, Esther S; Isoda, Fumiko; Kurland, Irwin; Mobbs, Charles V

    2013-09-01

    A major barrier in reversing diabetic complications is that molecular and pathologic effects of elevated glucose persist despite normalization of glucose, a phenomenon referred to as metabolic memory. In the present studies we have investigated the effects of elevated glucose on Schwann cells, which are implicated in diabetic neuropathy. Using quantitative PCR arrays for glucose and fatty acid metabolism, we have found that chronic (>8 wk) 25 mM high glucose induces a persistent increase in genes that promote glycolysis, while inhibiting those that oppose glycolysis and alternate metabolic pathways such as fatty acid metabolism, the pentose phosphate pathway, and trichloroacetic acid cycle. These sustained effects were associated with decreased peroxisome proliferator-activated receptor (PPAR)γ binding and persistently increased reactive oxygen species, cellular NADH, and altered DNA methylation. Agonists of PPARγ and PPARα prevented select effects of glucose-induced gene expression. These observations suggest that Schwann cells exhibit features of metabolic memory that may be regulated at the transcriptional level. Furthermore, targeting PPAR may prevent metabolic memory and the development of diabetic complications.

  18. Novel Programmable Shape Memory Polystyrene Film: A Thermally Induced Beam-power Splitter.

    Science.gov (United States)

    Li, Peng; Han, Yu; Wang, Wenxin; Liu, Yanju; Jin, Peng; Leng, Jinsong

    2017-03-09

    Micro/nanophotonic structures that are capable of optical wave-front shaping are implemented in optical waveguides and passive optical devices to alter the phase of the light propagating through them. The beam division directions and beam power distribution depend on the design of the micro/nanostructures. The ultimate potential of advanced micro/nanophotonic structures is limited by their structurally rigid, functional singleness and not tunable against external impact. Here, we propose a thermally induced optical beam-power splitter concept based on a shape memory polystyrene film with programmable micropatterns. The smooth film exhibits excellent transparency with a transmittance of 95% in the visible spectrum and optical stability during a continuous heating process up to 90 °C. By patterning double sided shape memory polystyrene film into erasable and switchable micro-groove gratings, the transmission light switches from one designed light divided directions and beam-power distribution to another because of the optical diffraction effect of the shape changing micro gratings during the whole thermal activated recovery process. The experimental and theoretical results demonstrate a proof-of-principle of the beam-power splitter. Our results can be adapted to further extend the applications of micro/nanophotonic devices and implement new features in the nanophotonics.

  19. Effects of metformin on inflammation and short-term memory in streptozotocin-induced diabetic mice.

    Science.gov (United States)

    Oliveira, Wilma Helena; Nunes, Ana Karolina; França, Maria Eduarda Rocha; Santos, Laise Aline; Lós, Deniele Bezerra; Rocha, Sura Wanessa; Barbosa, Karla Patrícia; Rodrigues, Gabriel Barros; Peixoto, Christina Alves

    2016-08-01

    The aim of the present study was to analyze the action of metformin on short-term memory, glial cell activation and neuroinflammation caused by experimental diabetic encephalopathy in C57BL/6 mice. Diabetes was induced by the intraperitoneal injection of a dose of 90mg/kg of streptozotocin on two successive days. Mice with blood glucose levels ≥200dl/ml were considered diabetic and were given metformin hydrochloride at doses of 100mg/kg and 200mg/kg (by gavage, twice daily) for 21 days. On the final day of treatment, the mice underwent a T-maze test. On the 22nd day of treatment all the animals were anesthetized and euthanized. Diabetic animals treated with metformin had a higher spatial memory score. The hippocampus of the diabetic animals presented reactive gliosis, neuronal loss, NF-kB signaling activation, and high levels of IL-1 and VEGF. In addition, the T-maze test scores of these animals were low. Treatment with metformin reduced the expression of GFAP, Iba-1 (astrocyte and microglial markers) and the inflammation markers (p-IKB, IL-1 and VEGF), while enhancing p-AMPK and eNOS levels and increasing neuronal survival (Fox-1 and NeuN). Treatment with metformin also improved the spatial memory scores of diabetic animals. In conclusion, the present study showed that metformin can significantly reduce neuroinflammation and can decrease the loss of neurons in the hippocampus of diabetic animals, which can subsequently promote improvements in spatial memory. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Perceptual, not memorial, disruption underlies emotion-induced blindness.

    Science.gov (United States)

    Kennedy, Briana L; Most, Steven B

    2012-04-01

    Emotion-induced blindness refers to impaired awareness of stimuli appearing in the temporal wake of an emotionally arousing stimulus (S. B. Most, Chun, Widders, & Zald, 2005). In previous emotion-induced blindness experiments, participants withheld target responses until the end of a rapid stream of stimuli, even though each target appeared in the middle of the stream. The resulting interval between the targets' offset and participants' initiation of a response leaves open the possibility that emotion-induced blindness reflects a failure to encode or maintain target information in memory rather than a failure of perception. In the present study, participants engaged in a typical emotion-induced blindness task but initiated a response immediately upon seeing each target. Emotion-induced blindness was nevertheless robust. This suggests that emotion-induced blindness is not attributable to the delay between awareness of a target and the initiation of a response, but rather reflects the disruptive impact of emotional distractors on mechanisms driving conscious perception. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

  1. Protective effects of cultured and fermented ginseng extracts against scopolamine-induced memory loss in a mouse model.

    Science.gov (United States)

    Han, Song-Hee; Kim, Sung-June; Yun, Young Won; Nam, Sang Yoon; Lee, Hu-Jang; Lee, Beom-Jun

    2018-03-01

    This study was performed to investigate the effect of a concentrate of fermented wild ginseng root culture (HLJG0701) on memory improvement in the scopolamine (SPL)-induced memory-deficient mouse model. Eight-week-old male ICR mice were used to evaluate the protective effect of HLJG0701 against the SPL-induced memory loss animal model. The Morris water maze test, which measures hippocampus-dependent learning ability, and the Y-maze test, a short-term memory assessment test, were performed and related markers were analyzed. HLJG0701-treated groups displayed significantly reduced acetylcholinesterase activity and increased acetylcholine level compared with the SPL-administered group (SPL-G) ( P memory loss by inhibiting acetylcholinesterase activity and preventing acetylcholine deficiency.

  2. Involvement of nitric oxide in granisetron improving effect on scopolamine-induced memory impairment in mice.

    Science.gov (United States)

    Javadi-Paydar, Mehrak; Zakeri, Marjan; Norouzi, Abbas; Rastegar, Hossein; Mirazi, Naser; Dehpour, Ahmad Reza

    2012-01-06

    Granisetron, a serotonin 5-HT(3) receptor antagonist, widely used as an antiemetic drug following chemotherapy, has been found to improve learning and memory. In this study, effects of granisetron on spatial recognition memory and fear memory and the involvement of nitric oxide (NO) have been determined in a Y-maze and passive avoidance test. Granisetron (3, 10mg/kg, intraperitoneally) was administered to scopolamine-induced memory-impaired mice prior to acquisition, consolidation and retrieval phases, either in the presence or in the absence of a non-specific NO synthase inhibitor, l-NAME (3, 10mg/kg, intraperitoneally); a specific inducible NO synthase (iNOS) inhibitor, aminoguanidine (100mg/kg); and a NO precursor, l-arginine (750 mg/kg). It is demonstrated that granisetron improved memory acquisition in a dose-dependent manner, but it was ineffective on consolidation and retrieval phases of memory. The beneficial effect of granisetron (10mg/kg) on memory acquisition was significantly reversed by l-NAME (10mg/kg) and aminoguanidine (100mg/kg); however, l-arginine (750 mg/kg) did not potentiate the effect of sub-effective dose of granisetron (3mg/kg) in memory acquisition phase. It is concluded that nitric oxide is probably involved in improvement of memory acquisition by granisetron in both spatial recognition memory and fear memory. This article is part of a Special Issue entitled The Cognitive Neuroscience. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Glucose administration attenuates spatial memory deficits induced by chronic low-power-density microwave exposure.

    Science.gov (United States)

    Lu, Yonghui; Xu, Shangcheng; He, Mindi; Chen, Chunhai; Zhang, Lei; Liu, Chuan; Chu, Fang; Yu, Zhengping; Zhou, Zhou; Zhong, Min

    2012-07-16

    Extensive evidence indicates that glucose administration attenuates memory deficits in rodents and humans, and cognitive impairment has been associated with reduced glucose metabolism and uptake in certain brain regions including the hippocampus. In the present study, we investigated whether glucose treatment attenuated memory deficits caused by chronic low-power-density microwave (MW) exposure, and the effect of MW exposure on hippocampal glucose uptake. We exposed Wistar rats to 2.45 GHz pulsed MW irradiation at a power density of 1 mW/cm(2) for 3 h/day, for up to 30 days. MW exposure induced spatial learning and memory impairments in rats. Hippocampal glucose uptake was also reduced by MW exposure in the absence or presence of insulin, but the levels of blood glucose and insulin were not affected. However, these spatial memory deficits were reversed by systemic glucose treatment. Our results indicate that glucose administration attenuates the spatial memory deficits induced by chronic low-power-density MW exposure, and reduced hippocampal glucose uptake may be associated with cognitive impairment caused by MW exposure. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Specific inhibition of cytotoxic memory cells produced against uv-induced tumors in uv-irradiation mice

    International Nuclear Information System (INIS)

    Thorn, R.M.

    1978-01-01

    Cytotoxic responses of uv-irradiated mice against syngeneic uv-induced tumors were measured by using a 51 Cr-release assay to determine if uv treatment induced a specific reduction of cytotoxic activity. The in vivo and in vitro primary responses against syngeneic tumors and allogeneic cells were unaffected, as was the ''memory'' response (in vivo stimulation, in vitro restimulation) against alloantigens. In contrast, the memory response of uv-treated mice against syngeneic, uv-induced tumors was consistently and significantly depressed. The cytotoxicity generated by tumor cell stimulation in vivo or in vitro was tumor-specific and T cell-dependent. Since the primary response against syngeneic uv-induced tumors produces apparently normal amounts of tumor-specific cytotoxic activity, uv-treated mice may not reject transplanted syngeneic tumors because of too few T effector memory cells. These results imply that, at least in this system, tumor rejection depends mostly on the secondary responses against tumor antigens and that at least one carcinogen can, indirectly, specifically regulate immune responses

  5. Method of computer generation and projection recording of microholograms for holographic memory systems: mathematical modelling and experimental implementation

    International Nuclear Information System (INIS)

    Betin, A Yu; Bobrinev, V I; Evtikhiev, N N; Zherdev, A Yu; Zlokazov, E Yu; Lushnikov, D S; Markin, V V; Odinokov, S B; Starikov, S N; Starikov, R S

    2013-01-01

    A method of computer generation and projection recording of microholograms for holographic memory systems is presented; the results of mathematical modelling and experimental implementation of the method are demonstrated. (holographic memory)

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

    Science.gov (United States)

    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.

  7. Chronic caffeine exposure attenuates blast-induced memory deficit in mice.

    Science.gov (United States)

    Ning, Ya-Lei; Yang, Nan; Chen, Xing; Zhao, Zi-Ai; Zhang, Xiu-Zhu; Chen, Xing-Yun; Li, Ping; Zhao, Yan; Zhou, Yuan-Guo

    2015-01-01

    To investigate the effects of three different ways of chronic caffeine administration on blast- induced memory dysfunction and to explore the underlying mechanisms. Adult male C57BL/6 mice were used and randomly divided into five groups: control: without blast exposure, con-water: administrated with water continuously before and after blast-induced traumatic brain injury (bTBI), con-caffeine: administrated with caffeine continuously for 1 month before and after bTBI, pre-caffeine: chronically administrated with caffeine for 1 month before bTBI and withdrawal after bTBI, post-caffeine: chronically administrated with caffeine after bTBI. After being subjected to moderate intensity of blast injury, mice were recorded for learning and memory performance using Morris water maze (MWM) paradigms at 1, 4, and 8 weeks post-blast injury. Neurological deficit scoring, glutamate concentration, proinflammatory cytokines production, and neuropathological changes at 24 h, 1, 4, and 8 weeks post-bTBI were examined to evaluate the brain injury in early and prolonged stages. Adenosine A1 receptor expression was detected using qPCR. All of the three ways of chronic caffeine exposure ameliorated blast-induced memory deficit, which is correlated with the neuroprotective effects against excitotoxicity, inflammation, astrogliosis and neuronal loss at different stages of injury. Continuous caffeine treatment played positive roles in both early and prolonged stages of bTBI; pre-bTBI and post-bTBI treatment of caffeine tended to exert neuroprotective effects at early and prolonged stages of bTBI respectively. Up-regulation of adenosine A1 receptor expression might contribute to the favorable effects of chronic caffeine consumption. Since caffeinated beverages are widely consumed in both civilian and military personnel and are convenient to get, the results may provide a promising prophylactic strategy for blast-induced neurotrauma and the consequent cognitive impairment.

  8. Nimodipine-induced hypotension but not nitroglycerin-induced hypotension preserves long- and short-term memory in adult mice.

    Science.gov (United States)

    Haile, Michael; Galoyan, Samuel; Li, Yong-Sheng; Cohen, Barry H; Quartermain, David; Blanck, Thomas; Bekker, Alex

    2012-05-01

    Acute hypotension may be implicated in cognitive dysfunction. L-type calcium channel blockers in the setting of hypoxia are protective of learning and memory. We tested the hypothesis that hypotension induced by nimodipine (NIMO) and nicardipine (NICA) would be protective of long- and short-term memory compared to hypotension induced by nitroglycerin (NTG). Forty Swiss-Webster mice (30 to 35 g, 6 to 8 weeks) were randomized into 4 groups for i.p. injection immediately after passive avoidance (PA) learning on day 0: (1) NTG (30 mg/kg); (2) NICA (40 mg/kg); (3) NIMO (40 mg/kg); and (4) saline. PA training latencies (seconds) were recorded for entry from a suspended platform into a Plexiglas tube where a shock (0.3 mA; 2-second duration) was automatically delivered. On day 2 latencies were recorded during a testing trial during which no shock was delivered. Latencies >900 seconds were assigned this value. Lower testing latency is indicative of an impairment of long-term associative memory. Forty-nine additional mice were randomized into similar groups for object recognition testing (ORT) and given i.p. injections on day 0. ORT measures short-term memory by exploiting the tendency of mice to prefer novel objects where a familiar object is present. On day 5 during training, 2 identical objects were placed in a circular arena and mice explored both for 15 minutes. A testing trial was conducted 1 hour later for 3 minutes after a novel object replaced a familiar one. Mice with intact memory spend about 65% of the time exploring the novel object. Mice with impaired memory devote equal time to each object. Recognition index (RI) is defined as the ratio of time spent exploring the novel object to time spent exploring both objects was the measure of memory. Mean arterial blood pressure (MAP), cerebral bloodflow, and body and brain oxygenation (PO(2)) studies were done in separate groups of mice to determine the dosages for matched degrees of hypotension and the physiological

  9. Kinetics of the deformation induced memory effect in polyamide-6

    NARCIS (Netherlands)

    Drongelen, van M.; Stroeks, A.A.M.; Peters, G.W.M.

    2015-01-01

    Nascent polyamide-6 shows a peculiar and irreversible effect; the quiescent crystallization kinetics on cooling are accelerated upon deformation in the melt, even after full relaxation of the melt. This phenomenon, known as the orientation (or better, deformation) induced memory effect of polyamide

  10. Individual Differences in Working Memory Capacity Predict Retrieval-Induced Forgetting

    Science.gov (United States)

    Aslan, Alp; Bauml, Karl-Heinz T.

    2011-01-01

    Selectively retrieving a subset of previously studied information enhances memory for the retrieved information but causes forgetting of related, nonretrieved information. Such retrieval-induced forgetting (RIF) has often been attributed to inhibitory executive-control processes that supposedly suppress the nonretrieved items' memory…

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

    Science.gov (United States)

    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).

  12. 5-HT1A receptor blockade targeting the basolateral amygdala improved stress-induced impairment of memory consolidation and retrieval in rats.

    Science.gov (United States)

    Sardari, M; Rezayof, A; Zarrindast, M-R

    2015-08-06

    The aim of the present study was to investigate the possible role of basolateral amygdala (BLA) 5-HT1A receptors in memory formation under stress. We also examined whether the blockade of these receptors is involved in stress-induced state-dependent memory. Adult male Wistar rats received cannula implants that bilaterally targeted the BLA. Long-term memory was examined using the step-through type of passive avoidance task. Behavioral stress was evoked by exposure to an elevated platform (EP) for 10, 20 and 30min. Post-training exposure to acute stress (30min) impaired the memory consolidation. In addition, pre-test exposure to acute stress-(20 and 30min) induced the impairment of memory retrieval. Interestingly, the memory impairment induced by post-training exposure to stress was restored in the animals that received 20- or 30-min pre-test stress exposure, suggesting stress-induced state-dependent memory retrieval. Post-training BLA-targeted injection of a selective 5-HT1A receptor antagonist, (S)-WAY-100135 (2μg/rat), prevented the impairing effect of stress on memory consolidation. Pre-test injection of the same doses of (S)-WAY-100135 that was targeted to the BLA also reversed stress-induced memory retrieval impairment. It should be considered that post-training or pre-test BLA-targeted injection of (S)-WAY-100135 (0.5-2μg/rat) by itself had no effect on the memory formation. Moreover, pre-test injection of (S)-WAY-100135 (2μg/rat) that targeted the BLA inhibited the stress-induced state-dependent memory retrieval. Taken together, our findings suggest that post-training or pre-test exposure to acute stress induced the impairment of memory consolidation, retrieval and state-dependent learning. The BLA 5-HT1A receptors have a critical role in learning and memory under stress. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. The influence of suggestibility on memory.

    Science.gov (United States)

    Nicolas, Serge; Collins, Thérèse; Gounden, Yannick; Roediger, Henry L

    2011-06-01

    We provide a translation of Binet and Henri's pioneering 1894 paper on the influence of suggestibility on memory. Alfred Binet (1857-1911) is famous as the author who created the IQ test that bears his name, but he is almost unknown as the psychological investigator who generated numerous original experiments and fascinating results in the study of memory. His experiments published in 1894 manipulated suggestibility in several ways to determine effects on remembering. Three particular modes of suggestion were employed to induce false recognitions: (1) indirect suggestion by a preconceived idea; (2) direct suggestion; and (3) collective suggestion. In the commentary we suggest that Binet and Henri's (1894) paper written over 115 years ago is still highly relevant even today. In particular, Binet's legacy lives on in modern research on misinformation effects in memory, in studies of conformity, and in experiments on the social contagion of memory. Copyright © 2010 Elsevier Inc. All rights reserved.

  14. Experimental study of thermo-mechanical behavior of a thermosetting shape-memory polymer

    Science.gov (United States)

    Liu, Ruoxuan; Li, Yunxin; Liu, Zishun

    2018-01-01

    The thermo-mechanical behavior of shape-memory polymers (SMPs) serves for the engineering applications of SMPs. Therefore the understanding of thermo-mechanical behavior of SMPs is of great importance. This paper investigates the influence of loading rate and loading level on the thermo-mechanical behavior of a thermosetting shape-memory polymer through experimental study. A series of cyclic tension tests and shape recovery tests at different loading conditions are performed to study the strain level and strain rate effect. The results of tension tests show that the thermosetting shape-memory polymer will behave as rubber material at temperature lower than the glass transition temperature (Tg) and it can obtain a large shape fix ratio at cyclic loading condition. The shape recovery tests exhibit that loading rate and loading level have little effect on the beginning and ending of shape recovery process of the thermose