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Sample records for samples long-term memory

  1. Long-term expression of human contextual fear and extinction memories involves amygdala, hippocampus and ventromedial prefrontal cortex: a reinstatement study in two independent samples.

    Lonsdorf, Tina B; Haaker, Jan; Kalisch, Raffael

    2014-12-01

    Human context conditioning studies have focused on acquisition and extinction. Subsequent long-term changes in fear behaviors not only depend on associative learning processes during those phases but also on memory consolidation processes and the later ability to retrieve and express fear and extinction memories. Clinical theories explain relapse after successful exposure-based treatment with return of fear memories and remission with stable extinction memory expression. We probed contextual fear and extinction memories 1 week (Day8) after conditioning (Day1) and subsequent extinction (Day2) by presenting conditioned contexts before (Test1) and after (Test2) a reinstatement manipulation. We find consistent activation patterns in two independent samples: activation of a subgenual part of the ventromedial prefrontal cortex before reinstatement (Test1) and (albeit with different temporal profiles between samples) of the amygdala after reinstatement (Test2) as well as up-regulation of anterior hippocampus activity after reinstatement (Test2 > Test1). These areas have earlier been implicated in the expression of cued extinction and fear memories. The present results suggest a general role for these structures in defining the balance between fear and extinction memories, independent of the conditioning mode. The results are discussed in the light of hypotheses implicating the anterior hippocampus in the processing of situational ambiguity.

  2. Climate Predictability and Long Term Memory

    Zhu, X.; Blender, R.; Fraedrich, K.; Liu, Z.

    2010-09-01

    The benefit of climate Long Term Memory (LTM) for long term prediction is assessed using data from a millennium control simulation with the atmosphere ocean general circulation model ECHAM5/MPIOM. The forecast skills are evaluated for surface temperature time series at individual grid points. LTM is characterised by the Hurst exponent in the power-law scaling of the fluctuation function which is determined by detrended fluctuation analysis (DFA). LTM with a Hurst exponent close to 0.9 occurs mainly in high latitude oceans, which are also characterized by high potential predictability. Climate predictability is diagnosed in terms of potentially predictable variance fractions. Explicit prediction experiments for various time steps are conducted on a grid point basis using an auto-correlation (AR1) predictor: in regions with LTM, prediction skills are beyond that expected from red noise persistence; exceptions occur in some areas in the southern oceans and over the northern hemisphere continents. Extending the predictability analysis to the fully forced simulation shows large improvement in prediction skills.

  3. The properties and mechanism of long-term memory in nonparametric volatility

    Li, Handong; Cao, Shi-Nan; Wang, Yan

    2010-08-01

    Recent empirical literature documents the presence of long-term memory in return volatility. But the mechanism of the existence of long-term memory is still unclear. In this paper, we investigate the origin and properties of long-term memory with nonparametric volatility, using high-frequency time series data of the Chinese Shanghai Composite Stock Price Index. We perform Detrended Fluctuation Analysis (DFA) on three different nonparametric volatility estimators with different sampling frequencies. For the same volatility series, the Hurst exponents reduce as the sampling time interval increases, but they are still larger than 1/2, which means that no matter how the interval changes, it still cannot change the existence of long memory. RRV presents a relatively stable property on long-term memory and is less influenced by sampling frequency. RV and RBV have some evolutionary trends depending on time intervals, which indicating that the jump component has no significant impact on the long-term memory property. This suggests that the presence of long-term memory in nonparametric volatility can be contributed to the integrated variance component. Considering the impact of microstructure noise, RBV and RRV still present long-term memory under various time intervals. We can infer that the presence of long-term memory in realized volatility is not affected by market microstructure noise. Our findings imply that the long-term memory phenomenon is an inherent characteristic of the data generating process, not a result of microstructure noise or volatility clustering.

  4. The Effect of Modality on Long-Term Recognition Memory.

    Dean, Raymond S.; And Others

    1988-01-01

    The effects of visual and auditory modes of input on long-term memory were examined in two experiments, each with 40 and 80 undergraduates, respectively. In both experiments, visual stimulus attributes were a more salient dimension than were auditory features in the long-term encoding and retrieval process. (SLD)

  5. Effects of Acute Exercise on Long-Term Memory

    Labban, Jeffrey D.; Etnier, Jennifer L.

    2011-01-01

    In this study, we tested the effect of acute exercise on long-term memory, specifically the timing of exercise relative to the memory challenge. We assessed memory via paragraph recall, in which participants listened to two paragraphs (exposure) and recounted them following a 35-min delay. Participants (n = 48) were randomly assigned to one of…

  6. Long-term memory, sleep, and the spacing effect.

    Bell, Matthew C; Kawadri, Nader; Simone, Patricia M; Wiseheart, Melody

    2014-01-01

    Many studies have shown that memory is enhanced when study sessions are spaced apart rather than massed. This spacing effect has been shown to have a lasting benefit to long-term memory when the study phase session follows the encoding session by 24 hours. Using a spacing paradigm we examined the impact of sleep and spacing gaps on long-term declarative memory for Swahili-English word pairs by including four spacing delay gaps (massed, 12 hours same-day, 12 hours overnight, and 24 hours). Results showed that a 12-hour spacing gap that includes sleep promotes long-term memory retention similar to the 24-hour gap. The findings support the importance of sleep to the long-term benefit of the spacing effect.

  7. Incidental Biasing of Attention from Visual Long-Term Memory

    Fan, Judith E.; Turk-Browne, Nicholas B.

    2016-01-01

    Holding recently experienced information in mind can help us achieve our current goals. However, such immediate and direct forms of guidance from working memory are less helpful over extended delays or when other related information in long-term memory is useful for reaching these goals. Here we show that information that was encoded in the past…

  8. Marijuana effects on long-term memory assessment and retrieval.

    Darley, C F; Tinklenberg, J R; Roth, W T; Vernon, S; Kopell, B S

    1977-05-01

    The ability of 16 college-educated male subjects to recall from long-term memory a series of common facts was tested during intoxication with marijuana extract calibrated to 0.3 mg/kg delta-9-tetrahydrocannabinol and during placebo conditions. The subjects' ability to assess their memory capabilities was then determined by measuring how certain they were about the accuracy of their recall performance and by having them predict their performance on a subsequent recognition test involving the same recall items. Marijuana had no effect on recall or recognition performance. These results do not support the view that marijuana provides access to facts in long-term storage which are inaccessible during non-intoxication. During both marijuana and placebo conditions, subjects could accurately predict their recognition memory performance. Hence, marijuana did not alter the subjects' ability to accurately assess what information resides in long-term memory even though they did not have complete access to that information.

  9. A quantitative proteomic analysis of long-term memory

    Rosenegger David

    2010-03-01

    Full Text Available Abstract Background Memory is the ability to store, retain, and later retrieve learned information. Long-term memory (LTM formation requires: DNA transcription, RNA translation, and the trafficking of newly synthesized proteins. Several components of these processes have already been identified. However, due to the complexity of the memory formation process, there likely remain many yet to be identified proteins involved in memory formation and persistence. Results Here we use a quantitative proteomic method to identify novel memory-associated proteins in neural tissue taken from animals that were trained in vivo to form a long-term memory. We identified 8 proteins that were significantly up-regulated, and 13 that were significantly down-regulated in the LTM trained animals as compared to two different control groups. In addition we found 19 proteins unique to the trained animals, and 12 unique proteins found only in the control animals. Conclusions These results both confirm the involvement of previously identified memory proteins such as: protein kinase C (PKC, adenylate cyclase (AC, and proteins in the mitogen-activated protein kinase (MAPK pathway. In addition these results provide novel protein candidates (e.g. UHRF1 binding protein on which to base future studies.

  10. Infants long-term memory for complex music

    Ilari, Beatriz; Polka, Linda; Costa-Giomi, Eugenia

    2002-05-01

    In this study we examined infants' long-term memory for two complex pieces of music. A group of thirty 7.5 month-old infants was exposed daily to one short piano piece (i.e., either the Prelude or the Forlane by Maurice Ravel) for ten consecutive days. Following the 10-day exposure period there was a two-week retention period in which no exposure to the piece occurred. After the retention period, infants were tested on the Headturn Preference Procedure. At test, 8 different excerpts of the familiar piece were mixed with 8 different foil excerpts of the unfamiliar one. Infants showed a significant preference for the familiar piece of music. A control group of fifteen nonexposed infants was also tested and showed no preferences for either piece of music. These results suggest that infants in the exposure group retained the familiar music in their long-term memory. This was demonstrated by their ability to discriminate between the different excerpts of both the familiar and the unfamiliar pieces of music, and by their preference for the familiar piece. Confirming previous findings (Jusczyk and Hohne, 1993; Saffran et al., 2000), in this study we suggest that infants can retain complex pieces of music in their long-term memory for two weeks.

  11. Long-term visual object recognition memory in aged rats.

    Platano, Daniela; Fattoretti, Patrizia; Balietti, Marta; Bertoni-Freddari, Carlo; Aicardi, Giorgio

    2008-04-01

    Aging is associated with memory impairments, but the neural bases of this process need to be clarified. To this end, behavioral protocols for memory testing may be applied to aged animals to compare memory performances with functional and structural characteristics of specific brain regions. Visual object recognition memory can be investigated in the rat using a behavioral task based on its spontaneous preference for exploring novel rather than familiar objects. We found that a behavioral task able to elicit long-term visual object recognition memory in adult Long-Evans rats failed in aged (25-27 months old) Wistar rats. Since no tasks effective in aged rats are reported in the literature, we changed the experimental conditions to improve consolidation processes to assess whether this form of memory can still be maintained for long term at this age: the learning trials were performed in a smaller box, identical to the home cage, and the inter-trial delays were shortened. We observed a reduction in anxiety in this box (as indicated by the lower number of fecal boli produced during habituation), and we developed a learning protocol able to elicit a visual object recognition memory that was maintained after 24 h in these aged rats. When we applied the same protocol to adult rats, we obtained similar results. This experimental approach can be useful to study functional and structural changes associated with age-related memory impairments, and may help to identify new behavioral strategies and molecular targets that can be addressed to ameliorate memory performances during aging.

  12. Wnt Signaling Is Required for Long-Term Memory Formation

    Ying Tan

    2013-09-01

    Full Text Available Wnt signaling regulates synaptic plasticity and neurogenesis in the adult nervous system, suggesting a potential role in behavioral processes. Here, we probed the requirement for Wnt signaling during olfactory memory formation in Drosophila using an inducible RNAi approach. Interfering with β-catenin expression in adult mushroom body neurons specifically impaired long-term memory (LTM without altering short-term memory. The impairment was reversible, being rescued by expression of a wild-type β-catenin transgene, and correlated with disruption of a cellular LTM trace. Inhibition of wingless, a Wnt ligand, and arrow, a Wnt coreceptor, also impaired LTM. Wingless expression in wild-type flies was transiently elevated in the brain after LTM conditioning. Thus, inhibiting three key components of the Wnt signaling pathway in adult mushroom bodies impairs LTM, indicating that this pathway mechanistically underlies this specific form of memory.

  13. Long-Term Ecological Monitoring Field Sampling Plan for 2007

    T. Haney

    2007-07-31

    This field sampling plan describes the field investigations planned for the Long-Term Ecological Monitoring Project at the Idaho National Laboratory Site in 2007. This plan and the Quality Assurance Project Plan for Waste Area Groups 1, 2, 3, 4, 5, 6, 7, 10, and Removal Actions constitute the sampling and analysis plan supporting long-term ecological monitoring sampling in 2007. The data collected under this plan will become part of the long-term ecological monitoring data set that is being collected annually. The data will be used t determine the requirements for the subsequent long-term ecological monitoring. This plan guides the 2007 investigations, including sampling, quality assurance, quality control, analytical procedures, and data management. As such, this plan will help to ensure that the resulting monitoring data will be scientifically valid, defensible, and of known and acceptable quality.

  14. Notch is required for long-term memory in Drosophila.

    Presente, Asaf; Boyles, Randy S; Serway, Christine N; de Belle, J Steven; Andres, Andrew J

    2004-02-10

    A role for Notch in the elaboration of existing neural processes is emerging that is distinct from the increasingly well understood function of this gene in binary cell-fate decisions. Several research groups, by using a variety of organisms, have shown that Notch is important in the development of neural ultrastructure. Simultaneously, Presenilin (Psn) was identified both as a key mediator of Notch signaling and as a site of genetic lesions that cause early-onset Alzheimer's disease. Here we demonstrate that Notch loss of function produces memory deficits in Drosophila melanogaster. The effects are specific to long-term memory, which is thought to depend on ultrastructural remodeling. We propose that Notch plays an important role in the neural plasticity underlying consolidated memory.

  15. Possibility of "superfast" consolidation of long-term memory.

    Podolski IYa

    1998-01-01

    Two new behavioural tests in rats are described which demonstrate the fast consolidation of the long-term memory (LTM) in a dangerous natural situation (water escape). It is shown that after one-trial learning of the motor skill (jumping out of the water), long-term memory traces are retained without forgetting and are resistant to the blockade of M-cholinoreceptors by scopolamine (2 mg/kg) and of D1/D2 dopamine receptors by haloperidol (10 mg/kg) as well as electroconvulsive shock applied tank wall, learning of necessary motor skills, automatization and minimization of the skilled movements in 1.5-3.0 min, after 5 to 7 trials at two-second intervals (superfast learning) is demonstrated. It is suggested that the superfast consolidation of LTM (several minutes) is possible in life-threatening situations, the necessary time being 1-2 orders of magnitude less than it is generally accepted in the modern theories of memory. The proposed behavioural models may be helpful in investigation of some fundamental physiological and molecular mechanisms of stable neuronal interactions, as a basis for LTM consolidation.

  16. Long-term working memory in text production.

    Kellogg, R T

    2001-01-01

    In reading and other high-level cognitive tasks, Ericsson and Kintsch (1995) proposed that the limited capacity of short-term working memory (STWM) is supplemented by long- term working memory (LTWM) for individuals with a high degree of domain-specific knowledge. In Experiment 1, college students (N = 80) wrote persuasive and narrative texts concerning baseball; domain-specific knowledge about baseball and verbal ability was assessed. The results showed that verbal ability and domain-specific knowledge independently affected writing skill, supporting the view that literacy depends on both knowledge sources and refuting one argument raised in support of the LTWM hypothesis. Experiment 2 (N = 42) replicated this outcome and tested the prediction that a high degree of domain-specific knowledge would lessen interference on a secondary task. The data supported the interference prediction, offering evidence that LTWM plays a role in the production of text.

  17. Examining the long-term stability of overgeneral autobiographical memory.

    Sumner, Jennifer A; Mineka, Susan; Zinbarg, Richard E; Craske, Michelle G; Vrshek-Schallhorn, Suzanne; Epstein, Alyssa

    2014-01-01

    Overgeneral autobiographical memory (OGM) is a proposed trait-marker for vulnerability to depression, but relatively little work has examined its long-term stability. This study investigated the stability of OGM over several years in 271 late adolescents and young adults participating in a larger longitudinal study of risk for emotional disorders. The Autobiographical Memory Test (AMT) was administered twice, with test-retest intervals ranging from approximately 3 to 6 years. There was evidence of significant but modest stability in OGM over several years. Specifically, Spearman rank correlations (ρs) between the proportions of specific and categoric memories generated on the two AMTs were .31 and .32, respectively. We did not find evidence that the stability of OGM was moderated by the length of the test-retest interval. Furthermore, the stability coefficients for OGM for individuals with and without a lifetime history of major depressive disorder (MDD) were relatively similar in magnitude and not significantly different from one another (ρs=.34 and .42 for the proportions of specific and categoric memories for those with a history of MDD; ρs=.31 for both the proportions of specific and categoric memories for those without a history of MDD). Implications for the conceptualisation of OGM are discussed.

  18. Working Memory, Long-Term Memory, and Medial Temporal Lobe Function

    Jeneson, Annette; Squire, Larry R.

    2012-01-01

    Early studies of memory-impaired patients with medial temporal lobe (MTL) damage led to the view that the hippocampus and related MTL structures are involved in the formation of long-term memory and that immediate memory and working memory are independent of these structures. This traditional idea has recently been revisited. Impaired performance…

  19. Early and late stages of working-memory maintenance contribute differentially to long-term memory formation

    Bergmann, H.C.; Kiemeneij, A.; Fernandez, G.S.E.; Kessels, R.P.C.

    2013-01-01

    The present paper investigated the role of early and late stages of working-memory maintenance, which have been suggested to differentially contribute to long-term memory formation. In experiment 1, we administered a delayed-match-to-sample task, requiring participants to remember line drawings of n

  20. Modulation of working memory updating: Does long-term memory lexical association matter?

    Artuso, Caterina; Palladino, Paola

    2016-02-01

    The aim of the present study was to investigate how working memory updating for verbal material is modulated by enduring properties of long-term memory. Two coexisting perspectives that account for the relation between long-term representation and short-term performance were addressed. First, evidence suggests that performance is more closely linked to lexical properties, that is, co-occurrences within the language. Conversely, other evidence suggests that performance is linked more to long-term representations which do not entail lexical/linguistic representations. Our aim was to investigate how these two kinds of long-term memory associations (i.e., lexical or nonlexical) modulate ongoing working memory activity. Therefore, we manipulated (between participants) the strength of the association in letters based on either frequency of co-occurrences (lexical) or contiguity along the sequence of the alphabet (nonlexical). Results showed a cost in working memory updating for strongly lexically associated stimuli only. Our findings advance knowledge of how lexical long-term memory associations between consonants affect working memory updating and, in turn, contribute to the study of factors which impact the updating process across memory systems.

  1. Observation of long term potentiation in papain-based memory devices

    Bag, A.

    2014-06-01

    Biological synaptic behavior in terms of long term potentiation has been observed in papain-based (plant protein) memory devices (memristors) for the first time. Improvement in long term potentiation depends on pulse amplitude and width (duration). Continuous/repetitive dc voltage sweep leads to an increase in memristor conductivity leading to a long term memory in the \\'learning\\' processes.

  2. Greater emotional arousal predicts poorer long-term memory of communication skills in couples.

    Baucom, Brian R; Weusthoff, Sarah; Atkins, David C; Hahlweg, Kurt

    2012-06-01

    Many studies have examined the importance of learning skills in behaviorally based couple interventions but none have examined predictors of long-term memory for skills. Associations between emotional arousal and long-term recall of communication skills delivered to couples during a behaviorally based relationship distress prevention program were examined in a sample of 49 German couples. Fundamental frequency (f(0)), a vocal measure of encoded emotional arousal, was measured during pre-treatment couple conflict. Higher levels of f(0) were linked to fewer skills remembered 11 years after completing the program, and women remembered more skills than men. Implications of results for behaviorally based couple interventions are discussed.

  3. Accessing forgotten memory traces from long-term memory via visual movements

    Estela eCamara

    2014-11-01

    Full Text Available Because memory retrieval often requires overt responses, it is difficult to determine to what extend forgetting occurs as a problem in explicit accessing of long-term memory traces. In this study, we used eye-tracking measures in combination with a behavioural task that favoured high forgetting rates to investigate the existence of memory traces from long-term memory in spite of failure in accessing them consciously. In 2 experiments, participants were encouraged to encode a large set of sound-picture-location associations. In a later test, sounds were presented and participants were instructed to visually scan, before a verbal memory report, for the correct location of the associated pictures in an empty screen. We found the reactivation of associated memories by sound cues at test biased oculomotor behaviour towards locations congruent with memory representations, even when participants failed to consciously provide a memory report of it. These findings reveal the emergence of a memory-guided behaviour that can be used to map internal representations of forgotten memories from long-term memory.

  4. Musical and Verbal Memory in Alzheimer's Disease: A Study of Long-Term and Short-Term Memory

    Menard, Marie-Claude; Belleville, Sylvie

    2009-01-01

    Musical memory was tested in Alzheimer patients and in healthy older adults using long-term and short-term memory tasks. Long-term memory (LTM) was tested with a recognition procedure using unfamiliar melodies. Short-term memory (STM) was evaluated with same/different judgment tasks on short series of notes. Musical memory was compared to verbal…

  5. Analysis of long term samples in Tore Supra

    Gauthier, E.; Grosman, A.; Valter, J.

    1994-12-31

    Long Term Samples have been installed on the inner call in Tore Supra to monitor the surface modification of the graphite tiles. Surfaces analysis have shown a very low metallic impurity concentration ({approx}10{sup 16} at /cm{sup 2}) dominated by stainless steel compounds. the high deuterium concentration (> 10{sup 18} at/cm{sup 2}) is due to a codeposition with carbon atoms. Carbon layers of about 1 {mu}m have been measured from which we deduced a carbon recycling coefficient R{sub c} = 0.99. (authors). 20 refs., 6 figs.

  6. Short- and long-term memory: differential involvement of neurotransmitter systems and signal transduction cascades

    MÔNICA R.M. VIANNA

    2000-09-01

    Full Text Available Since William James (1890 first distinguished primary from secondary memory, equivalent to short- and long-term memory, respectively, it has been assumed that short-term memory processes are in charge of cognition while long-term memory is being consolidated. From those days a major question has been whether short-term memory is merely a initial phase of long-term memory, or a separate phenomena. Recent experiments have shown that many treatments with specific molecular actions given into the hippocampus and related brain areas after one-trial avoidance learning can effectively cancel short-term memory without affecting long-term memory formation. This shows that short-term memory and long-term memory involve separate mechanisms and are independently processed. Other treatments, however, influence both memory types similarly, suggesting links between both at the receptor and at the post-receptor level, which should not be surprising as they both deal with nearly the same sensorimotor representations. This review examines recent advances in short- and long-term memory mechanisms based on the effect of intra-hippocampal infusion of drugs acting upon neurotransmitter and signal transduction systems on both memory types.

  7. A Long-Term Memory Competitive Process Model of a Common Procedural Error. Part II: Working Memory Load and Capacity

    2013-07-01

    A Long-Term Memory Competitive Process Model of a Common Procedural Error, Part II: Working Memory Load and Capacity Franklin P. Tamborello, II...00-00-2013 4. TITLE AND SUBTITLE A Long-Term Memory Competitive Process Model of a Common Procedural Error, Part II: Working Memory Load and...07370024.2011.601692 Tamborello, F. P., & Trafton, J. G. (2013). A long-term competitive process model of a common procedural error. In Proceedings of the 35th

  8. Spatio-temporal memories for machine learning: a long-term memory organization.

    Starzyk, Janusz A; He, Haibo

    2009-05-01

    Design of artificial neural structures capable of reliable and flexible long-term spatio-temporal memory is of paramount importance in machine intelligence. To this end, we propose a novel, biologically inspired, long-term memory (LTM) architecture. We intend to use it as a building block of a neuron-level architecture that is able to mimic natural intelligence through learning, anticipation, and goal-driven behavior. A mutual input enhancement and blocking structure is proposed, and its operation is discussed in detail. The paper focuses on a hierarchical memory organization, storage, recognition, and recall mechanisms. Simulation results of the proposed memory show its effectiveness, adaptability, and robustness. Accuracy of the proposed method is compared to other methods including Levenshtein distance method and a Markov chain.

  9. Molecular bases of long-term memories: a question of persistence.

    Dudai, Yadin

    2002-04-01

    The most distinctive attribute of long-term memory is persistence over time. New studies have uncovered many aspects of the molecular and cellular biology of synaptic plasticity, and the acquisition and consolidation of memory, which are thought to depend on synaptic plasticity. Much less, however, is known about the molecular and cellular biology of long-term memory persistence. Recent findings in the field are construed within the conceptual framework that proposes that consolidation and persistence of long-term memories require modulation of gene expression, which can culminate in synaptic remodeling. Whether modulation of gene expression, and particularly the ensuing morphological plasticity of the synapse, is permissive, causal or sufficient for the materialization and persistence of the long-term trace is, as yet, undetermined. How persistent is persistence? Renewed interest is focused on the possibility that some long-term memories consolidate anew with retrieval, and could, under certain conditions, become transiently shaky in this period of reconsolidation.

  10. Long-term outcomes of memory retrieval under stress

    Tollenaar, M.S.; Elzinga, B.M.; Spinhoven, P.; Everaerd, W.T.A.M.

    2008-01-01

    Previous studies have found impairing effects of stress hormones on memory retrieval. So far, it is unknown whether these impairments are temporary, persistent throughout time, or whether the strength of the memory trace changes after retrieval because of the effects of stress hormones on memory pro

  11. The role of the hippocampus in long-term memory: is it memory store or comparator?

    Kryukov, V I

    2008-03-01

    Several attempts have been made to reconcile a number of rival theories on the role of the hippocampus in long-term memory. Those attempts fail to explain the basic effects of the theories from the same point of view. We are reviewing the four major theories, and shall demonstrate, with the use of mathematical models of attention and memory, that only one theory is capable of reconciling all of them by explaining the basic effects of each theory in a unified fashion, without altogether sacrificing their individual contributions. The key issue here is whether or not a memory trace is ever stored in the hippocampus itself, and there is no reconciliation unless the answer to that question is that there is not. As a result of the reconciliation that we are proposing, there is a simple solution to several outstanding problems concerning the neurobiology of memory such as: consolidation and reconsolidation, persistency of long term memory, novelty detection, habituation, long-term potentiation, and the multifrequency oscillatory self-organization of the brain.

  12. The Role of Long-Term Memory in a Test of Visual Working Memory: Proactive Facilitation but No Proactive Interference

    Oberauer, Klaus; Awh, Edward; Sutterer, David W.

    2017-01-01

    We report 4 experiments examining whether associations in visual working memory are subject to proactive interference from long-term memory (LTM). Following a long-term learning phase in which participants learned the colors of 120 unique objects, a working memory (WM) test was administered in which participants recalled the precise colors of 3…

  13. Distinct dopamine neurons mediate reward signals for short- and long-term memories.

    Yamagata, Nobuhiro; Ichinose, Toshiharu; Aso, Yoshinori; Plaçais, Pierre-Yves; Friedrich, Anja B; Sima, Richard J; Preat, Thomas; Rubin, Gerald M; Tanimoto, Hiromu

    2015-01-13

    Drosophila melanogaster can acquire a stable appetitive olfactory memory when the presentation of a sugar reward and an odor are paired. However, the neuronal mechanisms by which a single training induces long-term memory are poorly understood. Here we show that two distinct subsets of dopamine neurons in the fly brain signal reward for short-term (STM) and long-term memories (LTM). One subset induces memory that decays within several hours, whereas the other induces memory that gradually develops after training. They convey reward signals to spatially segregated synaptic domains of the mushroom body (MB), a potential site for convergence. Furthermore, we identified a single type of dopamine neuron that conveys the reward signal to restricted subdomains of the mushroom body lobes and induces long-term memory. Constant appetitive memory retention after a single training session thus comprises two memory components triggered by distinct dopamine neurons.

  14. Word Length Effects in Long-Term Memory

    Tehan, Gerald; Tolan, Georgina Anne

    2007-01-01

    The word length effect has been a central feature of theorising about immediate memory. The notion that short-term memory traces rapidly decay unless refreshed by rehearsal is based primarily upon the finding that serial recall for short words is better than that for long words. The decay account of the word length effect has come under pressure…

  15. Lateral Habenula determines long-term storage of aversive memories

    Tomaiuolo, Micol; Gonzalez, Carolina; Medina, Jorge H.; Piriz, Joaquin

    2014-01-01

    The Lateral Habenula (LHb) is a small brain structure that codifies negative motivational value and has been related to major depression. It has been shown recently that LHb activation is sufficient to induce aversive associative learning; however the key question about whether LHb activation is required for an aversive memory to be formed has not been addressed. In this article we studied the function of the LHb in memory formation using the Inhibitory Avoidance task (IA). We found that LHb inactivation during IA training does not disrupt memory when assessed 24 h after, but abolishes it 7 days later, indicating that LHb activity during memory acquisition is not necessary for memory formation, but regulates its temporal stability. These effects suggest that LHb inactivation modifies subjective perception of the training experience. PMID:24860453

  16. Lateral Habenula determines long-term storage of aversive memories.

    Micol eTomaiuolo

    2014-05-01

    Full Text Available The Lateral Habenula (LHb is a small brain structure that codifies negative motivational value and has been related to major depression. It has been shown recently that LHb activation is sufficient to induce aversive associative learning; however the key question about whether LHb activation is required for an aversive memory to be formed has not been addressed. In this article we studied the function of the LHb in memory formation using the Inhibitory Avoidance task (IA. We found that LHb inactivation during IA training does not disrupt memory when assessed 24 hours after, but abolishes it 7 days later, indicating that LHb activity during memory acquisition is not necessary for memory formation, but regulates its temporal stability. These effects suggest that LHb inactivation modifies subjective perception of the training experience.

  17. Narrative organisation at encoding facilitated children's long-term episodic memory.

    Wang, Qi; Bui, Van-Kim; Song, Qingfang

    2015-01-01

    This study examined the effect of narrative organisation at encoding on long-term episodic memory in a sample of five- to seven-year-old children (N = 113). At an initial interview, children were asked to narrate a story from a picture book. Six months later, they were interviewed again and asked to recall the story and answer a series of direct questions about the story. Children who initially encoded more information in narrative and produced more complete, complex, cohesive and coherent narratives remembered the story in greater detail and accuracy following the six-month interval, independent of age and verbal skills. The relation between narrative organisation and memory was consistent across culture and gender. These findings provide new insight into the critical role of narrative in episodic memory.

  18. Early and late stages of working-memory maintenance contribute differentially to long-term memory formation.

    Bergmann, Heiko C; Kiemeneij, Anne; Fernández, Guillén; Kessels, Roy P C

    2013-06-01

    The present paper investigated the role of early and late stages of working-memory maintenance, which have been suggested to differentially contribute to long-term memory formation. In experiment 1, we administered a delayed-match-to-sample task, requiring participants to remember line drawings of non-sense three-dimensional stimuli. In the delay phase, participants were either presented with a fixation cross (for 2 or 9s) or with one of two different interference tasks, varying in visual overlap with the target. The interference task was presented 1.5, 4.5 or 7.5s after target offset. Early interfering and early probing disproportionately affected performance on an unexpected subsequent recognition-memory task compared to later interference or probing. This was not modulated by the type of interference task. In Experiment 2, we examined whether the formation of a holistic internal code of the target may be a gradual process. An analogous delayed-match-to-sample task was administered, with interference after 0.5, 2.5 or 4.5s after target offset. The early and middle interference condition similarly disproportionately affected performance compared to later interference. Hence, the present results support the view of a functional dissociation between early and late stages of working-memory maintenance and that early working-memory processes contribute particularly to long-term memory formation.

  19. Long-term Memory and Volatility Clustering in Daily and High-frequency Price Changes

    Oh, G J; Um, C J; Kim, Seunghwann; Oh, GabJin; Um, Cheol-Jun

    2006-01-01

    We study the long-term memory in diverse stock market indices and foreign exchange rates using the Detrended Fluctuation Analysis(DFA). For all daily and high-frequency market data studied, no significant long-term memory property is detected in the return series, while a strong long-term memory property is found in the volatility time series. The possible causes of the long-term memory property are investigated using the return data filtered by the AR(1) model, reflecting the short-term memory property, and the GARCH(1,1) model, reflecting the volatility clustering property, respectively. Notably, we found that the memory effect in the AR(1) filtered return and volatility time series remains unchanged, while the long-term memory property either disappeared or diminished significantly in the volatility series of the GARCH(1,1) filtered data. We also found that in the high-frequency data the long-term memory property may be generated by the volatility clustering as well as higher autocorrelation. Our results i...

  20. Early calcium increase triggers the formation of olfactory long-term memory in honeybees

    Matsumoto Yukihisa

    2009-06-01

    Full Text Available Abstract Background Synaptic plasticity associated with an important wave of gene transcription and protein synthesis underlies long-term memory processes. Calcium (Ca2+ plays an important role in a variety of neuronal functions and indirect evidence suggests that it may be involved in synaptic plasticity and in the regulation of gene expression correlated to long-term memory formation. The aim of this study was to determine whether Ca2+ is necessary and sufficient for inducing long-term memory formation. A suitable model to address this question is the Pavlovian appetitive conditioning of the proboscis extension reflex in the honeybee Apis mellifera, in which animals learn to associate an odor with a sucrose reward. Results By modulating the intracellular Ca2+ concentration ([Ca2+]i in the brain, we show that: (i blocking [Ca2+]i increase during multiple-trial conditioning selectively impairs long-term memory performance; (ii conversely, increasing [Ca2+]i during single-trial conditioning triggers long-term memory formation; and finally, (iii as was the case for long-term memory produced by multiple-trial conditioning, enhancement of long-term memory performance induced by a [Ca2+]i increase depends on de novo protein synthesis. Conclusion Altogether our data suggest that during olfactory conditioning Ca2+ is both a necessary and a sufficient signal for the formation of protein-dependent long-term memory. Ca2+ therefore appears to act as a switch between short- and long-term storage of learned information.

  1. DNA methylation mediates the discriminatory power of associative long-term memory in honeybees.

    Stephanie D Biergans

    Full Text Available Memory is created by several interlinked processes in the brain, some of which require long-term gene regulation. Epigenetic mechanisms are likely candidates for regulating memory-related genes. Among these, DNA methylation is known to be a long lasting genomic mark and may be involved in the establishment of long-term memory. Here we demonstrate that DNA methyltransferases, which induce and maintain DNA methylation, are involved in a particular aspect of associative long-term memory formation in honeybees, but are not required for short-term memory formation. While long-term memory strength itself was not affected by blocking DNA methyltransferases, odor specificity of the memory (memory discriminatory power was. Conversely, perceptual discriminatory power was normal. These results suggest that different genetic pathways are involved in mediating the strength and discriminatory power of associative odor memories and provide, to our knowledge, the first indication that DNA methyltransferases are involved in stimulus-specific associative long-term memory formation.

  2. Debra, a protein mediating lysosomal degradation, is required for long-term memory in Drosophila.

    Kottler, Benjamin; Lampin-Saint-Amaux, Aurélie; Comas, Daniel; Preat, Thomas; Goguel, Valérie

    2011-01-01

    A central goal of neuroscience is to understand how neural circuits encode memory and guide behavior changes. Many of the molecular mechanisms underlying memory are conserved from flies to mammals, and Drosophila has been used extensively to study memory processes. To identify new genes involved in long-term memory, we screened Drosophila enhancer-trap P(Gal4) lines showing Gal4 expression in the mushroom bodies, a specialized brain structure involved in olfactory memory. This screening led to the isolation of a memory mutant that carries a P-element insertion in the debra locus. debra encodes a protein involved in the Hedgehog signaling pathway as a mediator of protein degradation by the lysosome. To study debra's role in memory, we achieved debra overexpression, as well as debra silencing mediated by RNA interference. Experiments conducted with a conditional driver that allowed us to specifically restrict transgene expression in the adult mushroom bodies led to a long-term memory defect. Several conclusions can be drawn from these results: i) debra levels must be precisely regulated to support normal long-term memory, ii) the role of debra in this process is physiological rather than developmental, and iii) debra is specifically required for long-term memory, as it is dispensable for earlier memory phases. Drosophila long-term memory is the only long-lasting memory phase whose formation requires de novo protein synthesis, a process underlying synaptic plasticity. It has been shown in several organisms that regulation of proteins at synapses occurs not only at translation level of but also via protein degradation, acting in remodeling synapses. Our work gives further support to a role of protein degradation in long-term memory, and suggests that the lysosome plays a role in this process.

  3. Effects of age on long term memory for degraded speech

    Christiane Thiel

    2016-09-01

    Full Text Available Prior research suggests that acoustical degradation impacts encoding of items into memory, especially in elderly subjects. We here aimed to investigate whether acoustically degraded items, that are initially encoded into memory, are more prone to forgetting as a function of age. Young and old participants were tested with a vocoded and unvocoded serial list learning task involving immediate and delayed free recall. We found that degraded auditory input increased forgetting of previously encoded items, especially in older participants. We further found that working memory capacity predicted forgetting of degraded information in young participants. In old participants, verbal IQ was the most important predictor for forgetting acoustically degraded information. Our data provide evidence that acoustically degraded information, even if encoded, is especially vulnerable to forgetting in old age.

  4. GABA-Mediated Presynaptic Inhibition Is Required for Precision of Long-Term Memory

    Cullen, Patrick K.; Dulka, Brooke N.; Ortiz, Samantha; Riccio, David C.; Jasnow, Aaron M.

    2014-01-01

    Though much attention has been given to the neural structures that underlie the long-term consolidation of contextual memories, little is known about the mechanisms responsible for the maintenance of memory precision. Here, we demonstrate a rapid time-dependent decline in memory precision in GABA [subscript B(1a)] receptor knockout mice. First, we…

  5. The Neural Substrates of Recognition Memory for Verbal Information: Spanning the Divide between Short- and Long-Term Memory

    Buchsbaum, Bradley R.; Padmanabhan, Aarthi; Berman, Karen Faith

    2011-01-01

    One of the classic categorical divisions in the history of memory research is that between short-term and long-term memory. Indeed, because memory for the immediate past (a few seconds) and memory for the relatively more remote past (several seconds and beyond) are assumed to rely on distinct neural systems, more often than not, memory research…

  6. Long-term olfactory memories are stabilised via protein synthesis in Camponotus fellah ants

    Guerrieri, Fernando Javier; D'Ettorre, Patrizia; Deveaud, J-M.;

    2011-01-01

    of molecular bases of learning and memory. An open question is whether the memories formed upon olfactory learning that are retrievable several days after training are indeed based on de novo protein synthesis. Here, we addressed this question in the ant Camponotus fellah using a conditioning protocol in which......-chain hydrocarbons, one paired with sucrose and the other with quinine solution. Differential conditioning leads to the formation of a long-term memory retrievable at least 72¿h after training. Long-term memory consolidation was impaired by the ingestion of cycloheximide, a protein synthesis blocker, prior...... synthesis, long-term memories are stabilised via protein synthesis. Our behavioural protocol opens interesting research avenues to explore the cellular and molecular bases of olfactory learning and memory in ants....

  7. BDNF Variants May Modulate Long-Term Visual Memory Performance in a Healthy Cohort

    Nesli Avgan

    2017-03-01

    Full Text Available Brain-derived neurotrophic factor (BDNF is involved in numerous cognitive functions including learning and memory. BDNF plays an important role in synaptic plasticity in humans and rats with BDNF shown to be essential for the formation of long-term memories. We previously identified a significant association between the BDNF Val66Met polymorphism (rs6265 and long-term visual memory (p-value = 0.003 in a small cohort (n = 181 comprised of healthy individuals who had been phenotyped for various aspects of memory function. In this study, we have extended the cohort to 597 individuals and examined multiple genetic variants across both the BDNF and BDNF-AS genes for association with visual memory performance as assessed by the Wechsler Memory Scale—Fourth Edition subtests Visual Reproduction I and II (VR I and II. VR I assesses immediate visual memory, whereas VR II assesses long-term visual memory. Genetic association analyses were performed for 34 single nucleotide polymorphisms genotyped on Illumina OmniExpress BeadChip arrays with the immediate and long-term visual memory phenotypes. While none of the BDNF and BDNF-AS variants were shown to be significant for immediate visual memory, we found 10 variants (including the Val66Met polymorphism (p-value = 0.006 that were nominally associated, and three variants (two variants in BDNF and one variant in the BDNF-AS locus that were significantly associated with long-term visual memory. Our data therefore suggests a potential role for BDNF, and its anti-sense transcript BDNF-AS, in long-term visual memory performance.

  8. BDNF Variants May Modulate Long-Term Visual Memory Performance in a Healthy Cohort

    Avgan, Nesli; Sutherland, Heidi G.; Spriggens, Lauren K.; Yu, Chieh; Ibrahim, Omar; Bellis, Claire; Haupt, Larisa M.; Shum, David H. K.; Griffiths, Lyn R.

    2017-01-01

    Brain-derived neurotrophic factor (BDNF) is involved in numerous cognitive functions including learning and memory. BDNF plays an important role in synaptic plasticity in humans and rats with BDNF shown to be essential for the formation of long-term memories. We previously identified a significant association between the BDNF Val66Met polymorphism (rs6265) and long-term visual memory (p-value = 0.003) in a small cohort (n = 181) comprised of healthy individuals who had been phenotyped for various aspects of memory function. In this study, we have extended the cohort to 597 individuals and examined multiple genetic variants across both the BDNF and BDNF-AS genes for association with visual memory performance as assessed by the Wechsler Memory Scale—Fourth Edition subtests Visual Reproduction I and II (VR I and II). VR I assesses immediate visual memory, whereas VR II assesses long-term visual memory. Genetic association analyses were performed for 34 single nucleotide polymorphisms genotyped on Illumina OmniExpress BeadChip arrays with the immediate and long-term visual memory phenotypes. While none of the BDNF and BDNF-AS variants were shown to be significant for immediate visual memory, we found 10 variants (including the Val66Met polymorphism (p-value = 0.006)) that were nominally associated, and three variants (two variants in BDNF and one variant in the BDNF-AS locus) that were significantly associated with long-term visual memory. Our data therefore suggests a potential role for BDNF, and its anti-sense transcript BDNF-AS, in long-term visual memory performance. PMID:28304362

  9. Attention and available long-term memory in an activation-based model

    2010-01-01

    The influence of attention on memorizing related items and on available long-term memory (ALTM) was explored,showing that N400 of no-memory items was more negative than that of the memory item.The results of the category comparison task indicated that information processing under attention-driven in WM determined the availability of related long-term memory,i.e.,specific content,which was formerly concerned or ignored,yielding different indirect semantic priming effects.These indicate that the orientation of conceptual attention leads the related representations of LTM to diverse activation patterns,supporting the activation-based model.

  10. Post-Training Intrahippocampal Inhibition of Class I Histone Deacetylases Enhances Long-Term Object-Location Memory

    Hawk, Joshua D.; Florian, Cedrick; Abel, Ted

    2011-01-01

    Long-term memory formation involves covalent modification of the histone proteins that package DNA. Reducing histone acetylation by mutating histone acetyltransferases impairs long-term memory, and enhancing histone acetylation by inhibiting histone deacetylases (HDACs) improves long-term memory. Previous studies using HDAC inhibitors to enhance…

  11. Synaptic scaling enables dynamically distinct short- and long-term memory formation.

    Christian Tetzlaff

    2013-10-01

    Full Text Available Memory storage in the brain relies on mechanisms acting on time scales from minutes, for long-term synaptic potentiation, to days, for memory consolidation. During such processes, neural circuits distinguish synapses relevant for forming a long-term storage, which are consolidated, from synapses of short-term storage, which fade. How time scale integration and synaptic differentiation is simultaneously achieved remains unclear. Here we show that synaptic scaling - a slow process usually associated with the maintenance of activity homeostasis - combined with synaptic plasticity may simultaneously achieve both, thereby providing a natural separation of short- from long-term storage. The interaction between plasticity and scaling provides also an explanation for an established paradox where memory consolidation critically depends on the exact order of learning and recall. These results indicate that scaling may be fundamental for stabilizing memories, providing a dynamic link between early and late memory formation processes.

  12. Subjective Memory Ability and Long-Term Forgetting in Patients Referred for Neuropsychological Assessment.

    van der Werf, Sieberen P; Geurts, Sofie; de Werd, Maartje M E

    2016-01-01

    It has been suggested that the memory complaints of patients who are not impaired on formal memory tests may reflect accelerated forgetting. We examined this hypothesis by comparing the 1-week delayed recall and recognition test performance of outpatients who were referred for neuropsychological assessment and who had normal memory performance during standard memory assessment with that of a non-patient control group. Both groups performed equally in verbal learning and delayed recall. However, after 1 week, the patients performed worse than controls on both recall and recognition tests. Although subjective memory ability predicted short-term memory function in patients, it did not predict long-term delayed forgetting rates in either the patients or controls. Thus, long-term delayed recall and recognition intervals provided no additional value to explain poor subjective memory ability in the absence of objective memory deficits.

  13. Long-Term Episodic Memory in Children with Attention-Deficit/Hyperactivity Disorder

    Skowronek, Jeffrey S.; Leichtman, Michelle D.; Pillemer, David B.

    2008-01-01

    Twenty-nine grade-matched 4th-8th-grade males, 12 with attention-deficit/hyperactivity disorder (ADHD) (age M = 12.2 years, SD = 1.48), and 17 without (age M = 11.5, SD = 1.59), completed two working memory tasks (digit span and the Simon game) and three long-term episodic memory tasks (a personal event memory task, story memory task, and picture…

  14. Conversion of short-term to long-term memory in the novel object recognition paradigm.

    Moore, Shannon J; Deshpande, Kaivalya; Stinnett, Gwen S; Seasholtz, Audrey F; Murphy, Geoffrey G

    2013-10-01

    It is well-known that stress can significantly impact learning; however, whether this effect facilitates or impairs the resultant memory depends on the characteristics of the stressor. Investigation of these dynamics can be confounded by the role of the stressor in motivating performance in a task. Positing a cohesive model of the effect of stress on learning and memory necessitates elucidating the consequences of stressful stimuli independently from task-specific functions. Therefore, the goal of this study was to examine the effect of manipulating a task-independent stressor (elevated light level) on short-term and long-term memory in the novel object recognition paradigm. Short-term memory was elicited in both low light and high light conditions, but long-term memory specifically required high light conditions during the acquisition phase (familiarization trial) and was independent of the light level during retrieval (test trial). Additionally, long-term memory appeared to be independent of stress-mediated glucocorticoid release, as both low and high light produced similar levels of plasma corticosterone, which further did not correlate with subsequent memory performance. Finally, both short-term and long-term memory showed no savings between repeated experiments suggesting that this novel object recognition paradigm may be useful for longitudinal studies, particularly when investigating treatments to stabilize or enhance weak memories in neurodegenerative diseases or during age-related cognitive decline.

  15. An Account of Performance in Accessing Information Stored in Long-Term Memory. A Fixed-Links Model Approach

    Altmeyer, Michael; Schweizer, Karl; Reiss, Siegbert; Ren, Xuezhu; Schreiner, Michael

    2013-01-01

    Performance in working memory and short-term memory tasks was employed for predicting performance in a long-term memory task in order to find out about the underlying processes. The types of memory were represented by versions of the Posner Task, the Backward Counting Task and the Sternberg Task serving as measures of long-term memory, working…

  16. Combining stressors that individually impede long-term memory blocks all memory processes.

    Sarah Dalesman

    Full Text Available The effects of stress on memory are typically assessed individually; however, in reality different stressors are often experienced simultaneously. Here we determined the effect that two environmentally relevant stressors, crowding and low calcium availability, have on memory and neural activity following operant conditioning of aerial respiration in the pond snail, Lymnaea stagnalis. We measured aerial breathing behaviour and activity of a neuron necessary for memory formation, right pedal dorsal 1 (RPeD1, in the central pattern generator (CPG that drives aerial respiration in untrained animals, and assessed how these traits changed following training. In naïve animals both crowding and combined stressors significantly depressed burst activity in RPeD1 which correlated with a depression in aerial breathing behaviour, whereas low calcium availability had no effect on RPeD1 activity. Following training, changes in burst activity in RPeD1 correlated with behavioural changes, decreasing relative to their naïve state at 3 h and 24 h in control conditions when both intermediate-term memory (ITM: 3 h and long-term memory (LTM: 24 h are formed, at 3 h but not 24 h when exposed to individual stressors when only ITM is formed, and did not change in combined stressors (i.e. when no memory is formed. Additionally, we also found that Lymnaea formed short-term memory (STM: 10 min in the presence of individual stressors or under control conditions, but failed to do so in the presence of combined stressors. Our data demonstrate that by combining stressors that individually block LTM only we can block all memory processes. Therefore the effects of two stressors with similar individual affects on memory phenotype may be additive when experienced in combination.

  17. Hormonal and Monoamine Signaling during Reinforcement of Hippocampal Long-Term Potentiation and Memory Retrieval

    Korz, Volker; Frey, Julietta U.

    2007-01-01

    Recently it was shown that holeboard training can reinforce, i.e., transform early-LTP into late-LTP in the dentate gyrus during the initial formation of a long-term spatial reference memory in rats. The consolidation of LTP as well as of the reference memory was dependent on protein synthesis. We have now investigated the transmitter systems…

  18. Two Waves of Transcription Are Required for Long-Term Memory in the Honeybee

    Lefer, Damien; Perisse, Emmanuel; Hourcade, Benoit; Sandoz, JeanChristophe; Devaud, Jean-Marc

    2013-01-01

    Storage of information into long-term memory (LTM) usually requires at least two waves of transcription in many species. However, there is no clear evidence of this phenomenon in insects, which are influential models for memory studies. We measured retention in honeybees after injecting a transcription inhibitor at different times before and after…

  19. Individual Differences in the Effects of Retrieval from Long-Term Memory

    Brewer, Gene A.; Unsworth, Nash

    2012-01-01

    The current study examined individual differences in the effects of retrieval from long-term memory (i.e., the testing effect). The effects of retrieving from memory make tested information more accessible for future retrieval attempts. Despite the broad applied ramifications of such a potent memorization technique there is a paucity of research…

  20. Endogenous BDNF Is Required for Long-Term Memory Formation in the Rat Parietal Cortex

    Alonso, Mariana; Bekinschtein, Pedro, Cammarota, Martin; Vianna, Monica R. M.; Izquierdo, Ivan; Medina, Jorge H.

    2005-01-01

    Information storage in the brain is a temporally graded process involving different memory phases as well as different structures in the mammalian brain. Cortical plasticity seems to be essential to store stable long-term memories, although little information is available at the moment regarding molecular and cellular events supporting memory…

  1. Using electrophysiology to demonstrate that cueing affects long-term memory storage over the short term.

    Maxcey, Ashleigh M; Fukuda, Keisuke; Song, Won S; Woodman, Geoffrey F

    2015-10-01

    As researchers who study working memory, we often assume that participants keep a representation of an object in working memory when we present a cue that indicates that the object will be tested in a couple of seconds. This intuitively accounts for how well people can remember a cued object, relative to their memory for that same object presented without a cue. However, it is possible that this superior memory does not purely reflect storage of the cued object in working memory. We tested the hypothesis that cues presented during a stream of objects, followed by a short retention interval and immediate memory test, can change how information is handled by long-term memory. We tested this hypothesis by using a family of frontal event-related potentials believed to reflect long-term memory storage. We found that these frontal indices of long-term memory were sensitive to the task relevance of objects signaled by auditory cues, even when the objects repeated frequently, such that proactive interference was high. Our findings indicate the problematic nature of assuming process purity in the study of working memory, and demonstrate that frequent stimulus repetitions fail to isolate the role of working memory mechanisms.

  2. Hunger and memory; CRTC coordinates long-term memory with the physiological state, hunger.

    Hirano, Yukinori; Saitoe, Minoru

    2013-09-01

    Animals form and store memory, which advantageously adjusts their behavior later on. Although the growing body of evidences suggests the basic mechanisms of memory, it is not clear whether and in which physiological state memory functions can be altered. Here we discuss our recent study that mild fasting facilitates long-term memory (LTM) formation in Drosophila.(1) Canonical LTM in flies is induced by multiple training with rest intervals, and is mediated by a transcription factor, CREB and its binding protein, CBP. However, fasting allows LTM formation (fLTM) only by single-cycle training, in a manner dependent on another CREB binding protein, CRTC. Although it has been controversial, we are convinced that gene expression in a specific neural structure, called mushroom body (MB), is required for LTMs. We also showed data suggesting that reduced insulin signaling during fasting activates CRTC, thereby inducing fLTM formation. These data provides the conceptual advance that flies adapt their mechanisms for LTM formation according to their internal condition, hunger state. Due to limited food resources in the wild, fLTM could be one of the major form of LTM in natural environment. Furthermore, our data also indicate a novel conception that improvement of memory deficit might be achieved by activation of CRTC.

  3. [The molecular scenarios of the consolidation of long-term memory].

    Anokhin, K V

    1997-01-01

    Long-term memory consolidation is a critical event in the transition of short-lasting experiences into durable modifications of behaviour. Present article focuses on the problem of molecular bases of this process. It starts with a brief review of biochemical and pharmacological data demonstrating a universal dependence of long-term memory on gene expression in the brain. Some of the experimental studies of immediate early gene expression in the brain during learning are described in the second part of the article. A hypothesis is discussed according to which consolidation of long-term memory employ the same biphasic molecular cascade of gene expression that is used for cell growth and differentiation during development.

  4. Learning, memory and long-term potentiation are altered in Nedd4 heterozygous mice.

    Camera, Daria; Coleman, Harold A; Parkington, Helena C; Jenkins, Trisha A; Pow, David V; Boase, Natasha; Kumar, Sharad; Poronnik, Philip

    2016-04-15

    The consolidation of short-term memory into long-term memory involves changing protein level and activity for the synaptic plasticity required for long-term potentiation (LTP). AMPA receptor trafficking is a key determinant of LTP and recently ubiquitination by Nedd4 has been shown to play an important role via direct action on the GluA1 subunit, although the physiological relevance of these findings are yet to be determined. We therefore investigated learning and memory in Nedd4(+/-) mice that have a 50% reduction in levels of Nedd4. These mice showed decreased long-term spatial memory as evidenced by significant increases in the time taken to learn the location of and subsequently find a platform in the Morris water maze. In contrast, there were no significant differences between Nedd4(+/+) and Nedd4(+/-) mice in terms of short-term spatial memory in a Y-maze test. Nedd4(+/-) mice also displayed a significant reduction in post-synaptic LTP measured in hippocampal brain slices. Immunofluorescence of Nedd4 in the hippocampus confirmed its expression in hippocampal neurons of the CA1 region. These findings indicate that reducing Nedd4 protein by 50% significantly impairs LTP and long-term memory thereby demonstrating an important role for Nedd4 in these processes.

  5. Post-learning REM sleep deprivation impairs long-term memory: reversal by acute nicotine treatment.

    Aleisa, A M; Alzoubi, K H; Alkadhi, K A

    2011-07-15

    Rapid eye movement sleep deprivation (REM-SD) is associated with spatial learning and memory impairment. During REM-SD, an increase in nicotine consumption among habitual smokers and initiation of tobacco use by non-smokers have been reported. We have shown recently that nicotine treatment prevented learning and memory impairments associated with REM-SD. We now report the interactive effects of post-learning REM-SD and/or nicotine. The animals were first trained on the radial arm water maze (RAWM) task, then they were REM-sleep deprived using the modified multiple platform paradigm for 24h. During REM-SD period, the rats were injected with saline or nicotine (1mg/kg s.c. every 12h: a total of 3 injections). The animals were tested for long-term memory in the RAWM at the end of the REM-SD period. The 24h post-learning REM-SD significantly impaired long-term memory. However, nicotine treatment reversed the post-learning REM-SD-induced impairment of long-term memory. On the other hand, post-learning treatment of normal rats with nicotine for 24h enhanced long-term memory. These results indicate that post-learning acute nicotine treatment prevented the deleterious effect of REM-SD on cognitive abilities.

  6. The prion gene is associated with human long-term memory.

    Papassotiropoulos, Andreas; Wollmer, M Axel; Aguzzi, Adriano; Hock, Christoph; Nitsch, Roger M; de Quervain, Dominique J-F

    2005-08-01

    Human cognitive processes are highly variable across individuals and are influenced by both genetic and environmental factors. Although genetic variations affect short-term memory in humans, it is unknown whether genetic variability has also an impact on long-term memory. Because prion-like conformational changes may be involved in the induction of long-lasting synaptic plasticity, we examined the impact of single-nucleotide polymorphisms (SNPs) of the prion protein gene (PRNP) on long-term memory in healthy young humans. SNPs in the genomic region of PRNP were associated with better long-term memory performance in two independent populations with different educational background. Among the examined PRNP SNPs, the common Met129Val polymorphism yielded the highest effect size. Twenty-four hours after a word list-learning task, carriers of either the 129MM or the 129MV genotype recalled 17% more information than 129VV carriers, but short-term memory was unaffected. These results suggest a role for the prion protein in the formation of long-term memory in humans.

  7. Increased NR2A:NR2B ratio compresses long-term depression range and constrains long-term memory.

    Cui, Zhenzhong; Feng, Ruiben; Jacobs, Stephanie; Duan, Yanhong; Wang, Huimin; Cao, Xiaohua; Tsien, Joe Z

    2013-01-01

    The NR2A:NR2B subunit ratio of the NMDA receptors is widely known to increase in the brain from postnatal development to sexual maturity and to aging, yet its impact on memory function remains speculative. We have generated forebrain-specific NR2A overexpression transgenic mice and show that these mice had normal basic behaviors and short-term memory, but exhibited broad long-term memory deficits as revealed by several behavioral paradigms. Surprisingly, increased NR2A expression did not affect 1-Hz-induced long-term depression (LTD) or 100 Hz-induced long-term potentiation (LTP) in the CA1 region of the hippocampus, but selectively abolished LTD responses in the 3-5 Hz frequency range. Our results demonstrate that the increased NR2A:NR2B ratio is a critical genetic factor in constraining long-term memory in the adult brain. We postulate that LTD-like process underlies post-learning information sculpting, a novel and essential consolidation step in transforming new information into long-term memory.

  8. Can we throw information out of visual working memory and does this leave informational residue in long-term memory?

    Ashleigh Monette Maxcey

    2014-04-01

    Full Text Available Can we entirely erase a temporary memory representation from mind? This question has been addressed in several recent studies that tested the specific hypothesis that a representation can be erased from visual working memory based on a cue that indicated that the representation was no longer necessary for the task. In addition to behavioral results that are consistent with the idea that we can throw information out of visual working memory, recent neurophysiological recordings support this proposal. However, given the infinite capacity of long-term memory, it is unclear whether throwing a representation out of visual working memory really removes its effects on memory entirely. In this paper we advocate for an approach that examines our ability to erase memory representations from working memory, as well as possible traces that those erased representations leave in long-term memory.

  9. The short- and long-term fates of memory items retained outside the focus of attention.

    LaRocque, Joshua J; Eichenbaum, Adam S; Starrett, Michael J; Rose, Nathan S; Emrich, Stephen M; Postle, Bradley R

    2015-04-01

    When a test of working memory (WM) requires the retention of multiple items, a subset of them can be prioritized. Recent studies have shown that, although prioritized (i.e., attended) items are associated with active neural representations, unprioritized (i.e., unattended) memory items can be retained in WM despite the absence of such active representations, and with no decrement in their recognition if they are cued later in the trial. These findings raise two intriguing questions about the nature of the short-term retention of information outside the focus of attention. First, when the focus of attention shifts from items in WM, is there a loss of fidelity for those unattended memory items? Second, could the retention of unattended memory items be accomplished by long-term memory mechanisms? We addressed the first question by comparing the precision of recall of attended versus unattended memory items, and found a significant decrease in precision for unattended memory items, reflecting a degradation in the quality of those representations. We addressed the second question by asking subjects to perform a WM task, followed by a surprise memory test for the items that they had seen in the WM task. Long-term memory for unattended memory items from the WM task was not better than memory for items that had remained selected by the focus of attention in the WM task. These results show that unattended WM representations are degraded in quality and are not preferentially represented in long-term memory, as compared to attended memory items.

  10. Metamemory ratings predict long-term changes in reactivated episodic memories

    Amnon eYacoby

    2015-02-01

    Full Text Available Reactivation of long-term memory can render the memory item temporarily labile, offering an opportunity to modify it via behavioral or pharmacological intervention. Declarative memory reactivation is accompanied by a metamemory ability to subjectively assess the knowledge available concerning the target item (Feeling of knowing, FOK. We set out to examine whether FOK can predict the extent of change of long-term episodic memories by post-retrieval manipulations. To this end, participants watched a short movie and immediately thereafter tested on their memory for it. A day later, they were reminded of that movie, and either immediately or one day later, were presented with a second movie. The reminder phase consisted of memory cues to which participants were asked to judge their FOK regarding the original movie. The memory performance of participants to whom new information was presented immediately after reactivating the original episode corresponded to the degree of FOK ratings upon reactivation such that the lower their FOK, the less their memory declined. In contrast, no relation was found between FOK and memory strength for those who learned new information one day after the reminder phase. Our findings suggest that the subjective accessibility of reactivated memories may determine the extent to which new information might modify those memories.

  11. Long-term olfactory memories are stabilised via protein synthesis in Camponotus fellah ants

    Guerrieri, Fernando Javier; D'Ettorre, Patrizia; Deveaud, J-M.

    2011-01-01

    of molecular bases of learning and memory. An open question is whether the memories formed upon olfactory learning that are retrievable several days after training are indeed based on de novo protein synthesis. Here, we addressed this question in the ant Camponotus fellah using a conditioning protocol in which...... to conditioning. Cycloheximide did not impair acquisition of either short-term memory (10¿min) or early and late mid-term memories (1 or 12¿h). These results show that, upon olfactory learning, ants form different memories with variable molecular bases. While short- and mid-term memories do not require protein...... synthesis, long-term memories are stabilised via protein synthesis. Our behavioural protocol opens interesting research avenues to explore the cellular and molecular bases of olfactory learning and memory in ants....

  12. Mind the gap: delayed manifestation of long-term object memory improvement by phosphodiesterase inhibitors.

    Akkerman, S; Blokland, A; Prickaerts, J

    2014-03-01

    We examined the temporal profile of pharmacologically enhanced episodic memory, using the object recognition task. Male Wistar rats were tested at different retention intervals ranging from 1 h to 24 h. The object discrimination performance of all groups (untreated, placebo, drug treatment) gradually decreased up to an interval (8 h). Interestingly, only after this 8 h interval the memory improving effects of vardenafil and rolipram started to emerge. This time-dependent memory performance shows similarities with the Kamin effect. The delayed manifestation of drug-enhanced memory suggests that two separate memory mechanisms are at play, a quick transient form of memory and a more stable memory form that requires several hours to develop. It is important to take this into account when testing treatments intended for long-term memory enhancement.

  13. Deficits in long-term recognition memory reveal dissociated subtypes in congenital prosopagnosia.

    Stollhoff, Rainer; Jost, Jürgen; Elze, Tobias; Kennerknecht, Ingo

    2011-01-25

    The study investigates long-term recognition memory in congenital prosopagnosia (CP), a lifelong impairment in face identification that is present from birth. Previous investigations of processing deficits in CP have mostly relied on short-term recognition tests to estimate the scope and severity of individual deficits. We firstly report on a controlled test of long-term (one year) recognition memory for faces and objects conducted with a large group of participants with CP. Long-term recognition memory is significantly impaired in eight CP participants (CPs). In all but one case, this deficit was selective to faces and didn't extend to intra-class recognition of object stimuli. In a test of famous face recognition, long-term recognition deficits were less pronounced, even after accounting for differences in media consumption between controls and CPs. Secondly, we combined test results on long-term and short-term recognition of faces and objects, and found a large heterogeneity in severity and scope of individual deficits. Analysis of the observed heterogeneity revealed a dissociation of CP into subtypes with a homogeneous phenotypical profile. Thirdly, we found that among CPs self-assessment of real-life difficulties, based on a standardized questionnaire, and experimentally assessed face recognition deficits are strongly correlated. Our results demonstrate that controlled tests of long-term recognition memory are needed to fully assess face recognition deficits in CP. Based on controlled and comprehensive experimental testing, CP can be dissociated into subtypes with a homogeneous phenotypical profile. The CP subtypes identified align with those found in prosopagnosia caused by cortical lesions; they can be interpreted with respect to a hierarchical neural system for face perception.

  14. Deficits in long-term recognition memory reveal dissociated subtypes in congenital prosopagnosia.

    Rainer Stollhoff

    Full Text Available The study investigates long-term recognition memory in congenital prosopagnosia (CP, a lifelong impairment in face identification that is present from birth. Previous investigations of processing deficits in CP have mostly relied on short-term recognition tests to estimate the scope and severity of individual deficits. We firstly report on a controlled test of long-term (one year recognition memory for faces and objects conducted with a large group of participants with CP. Long-term recognition memory is significantly impaired in eight CP participants (CPs. In all but one case, this deficit was selective to faces and didn't extend to intra-class recognition of object stimuli. In a test of famous face recognition, long-term recognition deficits were less pronounced, even after accounting for differences in media consumption between controls and CPs. Secondly, we combined test results on long-term and short-term recognition of faces and objects, and found a large heterogeneity in severity and scope of individual deficits. Analysis of the observed heterogeneity revealed a dissociation of CP into subtypes with a homogeneous phenotypical profile. Thirdly, we found that among CPs self-assessment of real-life difficulties, based on a standardized questionnaire, and experimentally assessed face recognition deficits are strongly correlated. Our results demonstrate that controlled tests of long-term recognition memory are needed to fully assess face recognition deficits in CP. Based on controlled and comprehensive experimental testing, CP can be dissociated into subtypes with a homogeneous phenotypical profile. The CP subtypes identified align with those found in prosopagnosia caused by cortical lesions; they can be interpreted with respect to a hierarchical neural system for face perception.

  15. Transcriptional regulation of long-term memory in the marine snail Aplysia

    Lee Yong-Seok

    2008-06-01

    Full Text Available Abstract Whereas the induction of short-term memory involves only covalent modifications of constitutively expressed preexisting proteins, the formation of long-term memory requires gene expression, new RNA, and new protein synthesis. On the cellular level, transcriptional regulation is thought to be the starting point for a series of molecular steps necessary for both the initiation and maintenance of long-term synaptic facilitation (LTF. The core molecular features of transcriptional regulation involved in the long-term process are evolutionally conserved in Aplysia, Drosophila, and mouse, and indicate that gene regulation by the cyclic AMP response element binding protein (CREB acting in conjunction with different combinations of transcriptional factors is critical for the expression of many forms of long-term memory. In the marine snail Aplysia, the molecular mechanisms that underlie the storage of long-term memory have been extensively studied in the monosynaptic connections between identified sensory neuron and motor neurons of the gill-withdrawal reflex. One tail shock or one pulse of serotonin (5-HT, a modulatory transmitter released by tail shocks, produces a transient facilitation mediated by the cAMP-dependent protein kinase leading to covalent modifications in the sensory neurons that results in an enhancement of transmitter release and a strengthening of synaptic connections lasting minutes. By contrast, repeated pulses of 5-hydroxytryptamine (5-HT induce a transcription- and translation-dependent long-term facilitation (LTF lasting more than 24 h and trigger the activation of a family of transcription factors in the presynaptic sensory neurons including ApCREB1, ApCREB2 and ApC/EBP. In addition, we have recently identified novel transcription factors that modulate the expression of ApC/EBP and also are critically involved in LTF. In this review, we examine the roles of these transcription factors during consolidation of LTF induced

  16. Interteaching and Lecture: A Comparison of Long-Term Recognition Memory

    Saville, Bryan K.; Bureau, Alex; Eckenrode, Claire; Fullerton, Alison; Herbert, Reanna; Maley, Michelle; Porter, Allen; Zombakis, Julie

    2014-01-01

    Although a number of studies suggest that interteaching is an effective alternative to traditional teaching methods, no studies have systematically examined whether interteaching improves long-term memory. In this study, we assigned students to different teaching conditions--interteaching, lecture, or control--and then gave them a multiple-choice…

  17. Nicotine uses neuron-glia communication to enhance hippocampal synaptic transmission and long-term memory.

    Mónica López-Hidalgo

    Full Text Available Nicotine enhances synaptic transmission and facilitates long-term memory. Now it is known that bi-directional glia-neuron interactions play important roles in the physiology of the brain. However, the involvement of glial cells in the effects of nicotine has not been considered until now. In particular, the gliotransmitter D-serine, an endogenous co-agonist of NMDA receptors, enables different types of synaptic plasticity and memory in the hippocampus. Here, we report that hippocampal long-term synaptic plasticity induced by nicotine was annulled by an enzyme that degrades endogenous D-serine, or by an NMDA receptor antagonist that acts at the D-serine binding site. Accordingly, both effects of nicotine: the enhancement of synaptic transmission and facilitation of long-term memory were eliminated by impairing glial cells with fluoroacetate, and were restored with exogenous D-serine. Together, these results show that glial D-serine is essential for the long-term effects of nicotine on synaptic plasticity and memory, and they highlight the roles of glial cells as key participants in brain functions.

  18. The long-term memory analysis of industrial indices of the Chinese stock market

    Yong, L.

    2008-02-01

    The main work of this paper is to apply the fractional market theory and time series analysis for analyzing various industrial indices of the Chinese stock market by rescaling range analysis. Hurst index and the long-term memory of price change in Chinese stock market are studied.

  19. Role of Proteasome-Dependent Protein Degradation in Long-Term Operant Memory in "Aplysia"

    Lyons, Lisa C.; Gardner, Jacob S.; Gandour, Catherine E.; Krishnan, Harini C.

    2017-01-01

    We investigated the in vivo role of protein degradation during intermediate (ITM) and long-term memory (LTM) in "Aplysia" using an operant learning paradigm. The proteasome inhibitor MG-132 inhibited the induction and molecular consolidation of LTM with no effect on ITM. Remarkably, maintenance of steady-state protein levels through…

  20. Long-Term Memory for Music: Infants Remember Tempo and Timbre

    Trainor, Laurel J.; Wu, Luann; Tsang, Christine D.

    2004-01-01

    We show that infants' long-term memory representations for melodies are not just reduced to the structural features of relative pitches and durations, but contain surface or performance tempo- and timbre-specific information. Using a head turn preference procedure, we found that after a one week exposure to an old English folk song, infants…

  1. The long-term memory analysis of industrial indices of the Chinese stock market

    Yong, L [Renmin University of China, Information School (China); Department of Mathematics, Beijing 100872 (China)], E-mail: linyong01@ruc.edu.cn

    2008-02-15

    The main work of this paper is to apply the fractional market theory and time series analysis for analyzing various industrial indices of the Chinese stock market by rescaling range analysis. Hurst index and the long-term memory of price change in Chinese stock market are studied.

  2. Nicotine uses neuron-glia communication to enhance hippocampal synaptic transmission and long-term memory.

    López-Hidalgo, Mónica; Salgado-Puga, Karla; Alvarado-Martínez, Reynaldo; Medina, Andrea Cristina; Prado-Alcalá, Roberto A; García-Colunga, Jesús

    2012-01-01

    Nicotine enhances synaptic transmission and facilitates long-term memory. Now it is known that bi-directional glia-neuron interactions play important roles in the physiology of the brain. However, the involvement of glial cells in the effects of nicotine has not been considered until now. In particular, the gliotransmitter D-serine, an endogenous co-agonist of NMDA receptors, enables different types of synaptic plasticity and memory in the hippocampus. Here, we report that hippocampal long-term synaptic plasticity induced by nicotine was annulled by an enzyme that degrades endogenous D-serine, or by an NMDA receptor antagonist that acts at the D-serine binding site. Accordingly, both effects of nicotine: the enhancement of synaptic transmission and facilitation of long-term memory were eliminated by impairing glial cells with fluoroacetate, and were restored with exogenous D-serine. Together, these results show that glial D-serine is essential for the long-term effects of nicotine on synaptic plasticity and memory, and they highlight the roles of glial cells as key participants in brain functions.

  3. How long-term memory and accentuation interact during spoken language comprehension.

    Li, Xiaoqing; Yang, Yufang

    2013-04-01

    Spoken language comprehension requires immediate integration of different information types, such as semantics, syntax, and prosody. Meanwhile, both the information derived from speech signals and the information retrieved from long-term memory exert their influence on language comprehension immediately. Using EEG (electroencephalogram), the present study investigated how the information retrieved from long-term memory interacts with accentuation during spoken language comprehension. Mini Chinese discourses were used as stimuli, with an interrogative or assertive context sentence preceding the target sentence. The target sentence included one critical word conveying new information. The critical word was either highly expected or lowly expected given the information retrieved from long-term memory. Moreover, the critical word was either consistently accented or inconsistently de-accented. The results revealed that for lowly expected new information, inconsistently de-accented words elicited a larger N400 and larger theta power increases (4-6 Hz) than consistently accented words. In contrast, for the highly expected new information, consistently accented words elicited a larger N400 and larger alpha power decreases (8-14 Hz) than inconsistently de-accented words. The results suggest that, during spoken language comprehension, the effect of accentuation interacted with the information retrieved from long-term memory immediately. Moreover, our results also have important consequences for our understanding of the processing nature of the N400. The N400 amplitude is not only enhanced for incorrect information (new and de-accented word) but also enhanced for correct information (new and accented words).

  4. Demonstration of long-term memory in the parasitic wasp Nasonia vitripennis

    Schurmann, D.; Sommer, C.; Schinko, A.P.B.; Greschista, M.; Smid, H.M.; Steidle, J.L.M.

    2012-01-01

    We studied the formation of protein synthesis-dependent long-term memory (LTM) in the parasitic wasp Nasonia vitripennis Walker (Hymenoptera: Pteromalidae), a parasitoid of fly pupae. Female wasps were trained in one of five different training procedures in the presence of hosts and the odour cinnam

  5. Long-term memory of hierarchical relationships in free-living greylag geese

    Weiss, Brigitte M.; Scheiber, Isabella B. R.

    2013-01-01

    Animals may memorise spatial and social information for many months and even years. Here, we investigated long-term memory of hierarchically ordered relationships, where the position of a reward depended on the relationship of a stimulus relative to other stimuli in the hierarchy. Seventeen greylag

  6. Long-Term Behaviors of Stochastic Interest Rate Models with Jumps and Memory

    Bao, Jianhai

    2011-01-01

    In this paper we show the convergence of the long-term return $t^{-\\mu}\\int_0^tX(s)\\d s$ for some $\\mu\\geq1$, where $X$ is the short-term interest rate which follows an extension of Cox-Ingersoll-Ross type model with jumps and memory, and, as an application, we also investigate the corresponding behavior of two-factor Cox-Ingersoll-Ross model with jumps and memory

  7. Long-term olfactory memories are stabilised via protein synthesis in Camponotus fellah ants.

    Guerrieri, Fernando J; d'Ettorre, Patrizia; Devaud, Jean-Marc; Giurfa, Martin

    2011-10-01

    Ants exhibit impressive olfactory learning abilities. Operant protocols in which ants freely choose between rewarded and non-rewarded odours have been used to characterise associative olfactory learning and memory. Yet, this approach precludes the use of invasive methods allowing the dissection of molecular bases of learning and memory. An open question is whether the memories formed upon olfactory learning that are retrievable several days after training are indeed based on de novo protein synthesis. Here, we addressed this question in the ant Camponotus fellah using a conditioning protocol in which individually harnessed ants learn an association between odour and reward. When the antennae of an ant are stimulated with sucrose solution, the insect extends its maxilla-labium to absorb the solution (maxilla-labium extension response). We differentially conditioned ants to discriminate between two long-chain hydrocarbons, one paired with sucrose and the other with quinine solution. Differential conditioning leads to the formation of a long-term memory retrievable at least 72 h after training. Long-term memory consolidation was impaired by the ingestion of cycloheximide, a protein synthesis blocker, prior to conditioning. Cycloheximide did not impair acquisition of either short-term memory (10 min) or early and late mid-term memories (1 or 12 h). These results show that, upon olfactory learning, ants form different memories with variable molecular bases. While short- and mid-term memories do not require protein synthesis, long-term memories are stabilised via protein synthesis. Our behavioural protocol opens interesting research avenues to explore the cellular and molecular bases of olfactory learning and memory in ants.

  8. Memory signals from the thalamus: early thalamocortical phase synchronization entrains gamma oscillations during long-term memory retrieval.

    Staudigl, Tobias; Zaehle, Tino; Voges, Jürgen; Hanslmayr, Simon; Esslinger, Christine; Hinrichs, Hermann; Schmitt, Friedhelm C; Heinze, Hans-Jochen; Richardson-Klavehn, Alan

    2012-12-01

    The thalamus is believed to be a key node in human memory networks, however, very little is known about its real-time functional role. Here we examined the dynamics of thalamocortical communication during long-term episodic memory retrieval in two experiments. In experiment 1, intrathalamic and surface EEG was recorded in an epileptic patient implanted with depth electrodes for brain stimulation therapy. In a recognition memory test, early (300-500 ms) stimulus-linked oscillatory synchrony between mediodorsal thalamic and frontal surface electrodes at beta frequency (20 Hz) was enhanced for correctly remembered old compared to correctly rejected new items. Directionality measures (Granger causality) indicated that the thalamus was the sender, and the neocortex the receiver, of this beta signal, which also modulated the power of neocortical gamma (55-80 Hz) oscillations (cross-frequency coupling). Experiment 2 validated the cross-frequency coupling effects in a healthy participant sample. Confirming the findings from experiment 1, significantly increased cross-frequency coupling was found over frontal scalp electrodes during successful recognition. Extending anatomical knowledge on thalamic connectivity with frontal neocortex, these results suggest that the thalamus sends an early memory signal to frontal regions, triggering further memory search processes.

  9. Implicit short- and long-term memory direct our gaze in visual search.

    Kruijne, Wouter; Meeter, Martijn

    2016-04-01

    Visual attention is strongly affected by the past: both by recent experience and by long-term regularities in the environment that are encoded in and retrieved from memory. In visual search, intertrial repetition of targets causes speeded response times (short-term priming). Similarly, targets that are presented more often than others may facilitate search, even long after it is no longer present (long-term priming). In this study, we investigate whether such short-term priming and long-term priming depend on dissociable mechanisms. By recording eye movements while participants searched for one of two conjunction targets, we explored at what stages of visual search different forms of priming manifest. We found both long- and short- term priming effects. Long-term priming persisted long after the bias was present, and was again found even in participants who were unaware of a color bias. Short- and long-term priming affected the same stage of the task; both biased eye movements towards targets with the primed color, already starting with the first eye movement. Neither form of priming affected the response phase of a trial, but response repetition did. The results strongly suggest that both long- and short-term memory can implicitly modulate feedforward visual processing.

  10. Distinct neural correlates of associative working memory and long-term memory encoding in the medial temporal lobe

    Bergmann, H.C.; Rijpkema, M.J.P.; Fernandez, G.S.E.; Kessels, R.P.C.

    2012-01-01

    Increasing evidence suggests a role for the hippocampus not only in long-term memory (LTM) but also in relational working memory (WM) processes, challenging the view of the hippocampus as being solely involved in episodic LTM. However, hippocampal involvement reported in some neuroimaging studies us

  11. Making memories: the development of long-term visual knowledge in children with visual agnosia.

    Metitieri, Tiziana; Barba, Carmen; Pellacani, Simona; Viggiano, Maria Pia; Guerrini, Renzo

    2013-01-01

    There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2  years and 3.7  years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment.

  12. Making Memories: The Development of Long-Term Visual Knowledge in Children with Visual Agnosia

    Tiziana Metitieri

    2013-01-01

    Full Text Available There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2 years and 3.7 years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment.

  13. Cues, context, and long-term memory: the role of the retrosplenial cortex in spatial cognition

    Adam M P Miller

    2014-08-01

    Full Text Available Spatial navigation requires representations of landmarks and other navigation cues. The retrosplenial cortex (RSC is anatomically positioned between limbic areas important for memory formation, such as the hippocampus and the anterior thalamus, and cortical regions along the dorsal stream known to contribute importantly to long-term spatial representation, such as the posterior parietal cortex. Damage to the RSC severely impairs allocentric representations of the environment, including the ability to derive navigational information from landmarks. The specific deficits seen in tests of human and rodent navigation suggest that the RSC supports allocentric representation by processing the stable features of the environment and the spatial relationships among them. In addition to spatial cognition, the RSC plays a key role in contextual and episodic memory. The RSC also contributes importantly to the acquisition and consolidation of long-term spatial and contextual memory through its interactions with the hippocampus. Within this framework, the RSC plays a dual role as part of the feedforward network providing sensory and mnemonic input to the hippocampus and as a target of the hippocampal-dependent systems consolidation of long-term memory.

  14. Long-term memory of hierarchical relationships in free-living greylag geese.

    Weiss, Brigitte M; Scheiber, Isabella B R

    2013-01-01

    Animals may memorise spatial and social information for many months and even years. Here, we investigated long-term memory of hierarchically ordered relationships, where the position of a reward depended on the relationship of a stimulus relative to other stimuli in the hierarchy. Seventeen greylag geese (Anser anser) had been trained on discriminations between successive pairs of five or seven implicitly ordered colours, where the higher ranking colour in each pair was rewarded. Geese were re-tested on the task 2, 6 and 12 months after learning the dyadic colour relationships. They chose the correct colour above chance at all three points in time, whereby performance was better in colour pairs at the beginning or end of the colour series. Nonetheless, they also performed above chance on internal colour pairs, which is indicative of long-term memory for quantitative differences in associative strength and/or for relational information. There were no indications for a decline in performance over time, indicating that geese may remember dyadic relationships for at least 6 months and probably well over 1 year. Furthermore, performance in the memory task was unrelated to the individuals' sex and their performance while initially learning the dyadic colour relationships. We discuss possible functions of this long-term memory in the social domain.

  15. Reward improves long-term retention of a motor memory through induction of offline memory gains.

    Abe, Mitsunari; Schambra, Heidi; Wassermann, Eric M; Luckenbaugh, Dave; Schweighofer, Nicolas; Cohen, Leonardo G

    2011-04-12

    In humans, training in which good performance is rewarded or bad performance punished results in transient behavioral improvements. The relative effects of reward and punishment on consolidation and long-term retention, critical behavioral stages for successful learning, are not known. Here, we investigated the effects of reward and punishment on these different stages of human motor skill learning. We studied healthy subjects who trained on a motor task under rewarded, punished, or neutral control conditions. Performance was tested before and immediately, 6 hr, 24 hr, and 30 days after training in the absence of reward or punishment. Performance improvements immediately after training were comparable in the three groups. At 6 hr, the rewarded group maintained performance gains, whereas the other two groups experienced significant forgetting. At 24 hr, the reward group showed significant offline (posttraining) improvements, whereas the other two groups did not. At 30 days, the rewarded group retained the gains identified at 24 hr, whereas the other two groups experienced significant forgetting. We conclude that training under rewarded conditions is more effective than training under punished or neutral conditions in eliciting lasting motor learning, an advantage driven by offline memory gains that persist over time.

  16. Late Protein Synthesis-Dependent Phases in CTA Long-Term Memory: BDNF Requirement

    Martínez-Moreno, Araceli; Rodríguez-Durán, Luis F.; Escobar, Martha L.

    2011-01-01

    It has been proposed that long-term memory (LTM) persistence requires a late protein synthesis-dependent phase, even many hours after memory acquisition. Brain-derived neurotrophic factor (BDNF) is an essential protein synthesis product that has emerged as one of the most potent molecular mediators for long-term synaptic plasticity. Studies in the rat hippocampus have been shown that BDNF is capable to rescue the late-phase of long-term potentiation as well as the hippocampus-related LTM when protein synthesis was inhibited. Our previous studies on the insular cortex (IC), a region of the temporal cortex implicated in the acquisition and storage of conditioned taste aversion (CTA), have demonstrated that intracortical delivery of BDNF reverses the deficit in CTA memory caused by the inhibition of IC protein synthesis due to anisomycin administration during early acquisition. In this work, we first analyze whether CTA memory storage is protein synthesis-dependent in different time windows. We observed that CTA memory become sensible to protein synthesis inhibition 5 and 7 h after acquisition. Then, we explore the effect of BDNF delivery (2 μg/2 μl per side) in the IC during those late protein synthesis-dependent phases. Our results show that BDNF reverses the CTA memory deficit produced by protein synthesis inhibition in both phases. These findings support the notion that recurrent rounds of consolidation-like events take place in the neocortex for maintenance of CTA memory trace and that BDNF is an essential component of these processes. PMID:21960964

  17. Making synapses strong: metaplasticity prolongs associativity of long-term memory by switching synaptic tag mechanisms.

    Li, Qin; Rothkegel, Martin; Xiao, Zhi Cheng; Abraham, Wickliffe C; Korte, Martin; Sajikumar, Sreedharan

    2014-02-01

    One conceptual mechanism for the induction of associative long-term memory is that a synaptic tag, set by a weak event, can capture plasticity-related proteins from a nearby strong input, thus enabling associativity between the 2 (synaptic tagging and capture, STC). So far, STC has been observed for only a limited time of 60 min. Nevertheless, association of weak memory forms can occur beyond this period and its mechanism is not well understood. Here we report that metaplasticity induced by ryanodine receptor activation or synaptic activation of metabotropic glutamate receptors prolongs the durability of the synaptic tag, thus extending the time window for associative interactions mediating storage of long-term memory. We provide evidence that such metaplasticity alters the mechanisms of STC from a CaMKII-mediated (in non-primed STC) to a protein kinase Mzeta (PKMζ)-mediated process (in primed STC). Thus the association of weak synapses with strong synapses in the "late" stage of associative memory formation occurs only through metaplasticity. The results also reveal that the short-lived, CaMKII-mediated tag may contribute to a mechanism for a fragile form of memory while metaplasticity enables a PKMζ-mediated synaptic tag capable of prolonged interactions that induce a more stable form of memory that is resistant to reversal.

  18. Cholestasis progression effects on long-term memory in bile duct ligation rats

    Nasrin Hosseini

    2014-01-01

    Full Text Available Background : There is evidence that cognitive functions are affected by some liver diseases such as cholestasis. Bile duct ligation induces cholestasis as a result of impaired liver function and cognition. This research investigates the effect of cholestasis progression on memory function in bile duct ligation rats. Materials and Methods: Male Wistar rats were randomly divided into five groups, which include: control group for BDL-7, control group for BDL-21, sham group (underwent laparotomy without bile duct ligation, BDL-7 group (7 days after bile duct ligation, and BDL-21 group (21 days after bile duct ligation. Step-through passive avoidance test was employed to examine memory function. In all groups, short-term (7 days after foot shock and long-term memories (21 days after foot shock were assessed. Results: Our results showed that liver function significantly decreased with cholestasis progression (P < 0.01. Also our findings indicated BDL-21 significantly impaired acquisition time (P < 0.05. Memory retrieval impaired 7 (P < 0.05 and 21 days (P < 0.001 after foot shock in BDL-7 and BDL-21 groups, respectively. Conclusion: Based on these findings, liver function altered in cholestasis and memory (short-term and long-term memory impaired with cholestasis progression in bile duct ligation rats. Further studies are needed to better insight the nature of progression of brain damage in cholestatic disease.

  19. NEREC, an effective brain mapping protocol for combined language and long-term memory functions.

    Perrone-Bertolotti, Marcela; Girard, Cléa; Cousin, Emilie; Vidal, Juan Ricardo; Pichat, Cédric; Kahane, Philippe; Baciu, Monica

    2015-12-01

    Temporal lobe epilepsy can induce functional plasticity in temporoparietal networks involved in language and long-term memory processing. Previous studies in healthy subjects have revealed the relative difficulty for this network to respond effectively across different experimental designs, as compared to more reactive regions such as frontal lobes. For a protocol to be optimal for clinical use, it has to first show robust effects in a healthy cohort. In this study, we developed a novel experimental paradigm entitled NEREC, which is able to reveal the robust participation of temporoparietal networks in a uniquely combined language and memory task, validated in an fMRI study with healthy subjects. Concretely, NEREC is composed of two runs: (a) an intermixed language-memory task (confrontation naming associated with encoding in nonverbal items, NE) to map language (i.e., word retrieval and lexico-semantic processes) combined with simultaneous long-term verbal memory encoding (NE items named but also explicitly memorized) and (b) a memory retrieval task of items encoded during NE (word recognition, REC) intermixed with new items. Word recognition is based on both perceptual-semantic familiarity (feeling of 'know') and accessing stored memory representations (remembering). In order to maximize the remembering and recruitment of medial temporal lobe structures, we increased REC difficulty by changing the modality of stimulus presentation (from nonverbal during NE to verbal during REC). We report that (a) temporoparietal activation during NE was attributable to both lexico-semantic (language) and memory (episodic encoding and semantic retrieval) processes; that (b) encoding activated the left hippocampus, bilateral fusiform, and bilateral inferior temporal gyri; and that (c) task recognition (recollection) activated the right hippocampus and bilateral but predominant left fusiform gyrus. The novelty of this protocol consists of (a) combining two tasks in one (language

  20. CNTRICS Imaging Biomarkers Final Task Selection: Long-Term Memory and Reinforcement Learning

    Ragland, John D.; Neal J Cohen; Cools, Roshan; Frank, Michael J.; Deborah E Hannula; Ranganath, Charan

    2011-01-01

    Functional imaging paradigms hold great promise as biomarkers for schizophrenia research as they can detect altered neural activity associated with the cognitive and emotional processing deficits that are so disabling to this patient population. In an attempt to identify the most promising functional imaging biomarkers for research on long-term memory (LTM), the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) initiative selected “item encoding and ret...

  1. Making Memories: The Development of Long-Term Visual Knowledge in Children with Visual Agnosia

    Tiziana Metitieri; Carmen Barba; Simona Pellacani; Maria Pia Viggiano; Renzo Guerrini

    2013-01-01

    There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the developme...

  2. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition

    Christof eKuhbandner

    2016-02-01

    Full Text Available Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one third of the words were tested and one third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After one week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

  3. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition.

    Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

    2016-01-01

    Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

  4. Measuring capital market efficiency: Long-term memory, fractal dimension and approximate entropy

    Kristoufek, Ladislav; Vosvrda, Miloslav

    2014-01-01

    We utilize long-term memory, fractal dimension and approximate entropy as input variables for the Efficiency Index [Kristoufek & Vosvrda (2013), Physica A 392]. This way, we are able to comment on stock market efficiency after controlling for different types of inefficiencies. Applying the methodology on 38 stock market indices across the world, we find that the most efficient markets are situated in the Eurozone (the Netherlands, France and Germany) and the least efficient ones in the Latin ...

  5. Statistical traces of long-term memories stored in strengths and patterns of synaptic connections

    2011-01-01

    Learning and long-term memory rely on plasticity of neural circuits. In adult cerebral cortex plasticity can result from potentiation and depression of synaptic strengths and structural reorganization of circuits through growth and retraction of dendritic spines. By analyzing 166 distributions of spine head volumes and spine lengths from mouse, rat, monkey, and human brains, we determine the “generalized cost” of dendritic spines. This cost universally depends on spine shape, i.e. the depende...

  6. PKMzeta maintains spatial, instrumental, and classically conditioned long-term memories.

    Peter Serrano

    2008-12-01

    Full Text Available How long-term memories are stored is a fundamental question in neuroscience. The first molecular mechanism for long-term memory storage in the brain was recently identified as the persistent action of protein kinase Mzeta (PKMzeta, an autonomously active atypical protein kinase C (PKC isoform critical for the maintenance of long-term potentiation (LTP. PKMzeta maintains aversively conditioned associations, but what general form of information the kinase encodes in the brain is unknown. We first confirmed the specificity of the action of zeta inhibitory peptide (ZIP by disrupting long-term memory for active place avoidance with chelerythrine, a second inhibitor of PKMzeta activity. We then examined, using ZIP, the effect of PKMzeta inhibition in dorsal hippocampus (DH and basolateral amygdala (BLA on retention of 1-d-old information acquired in the radial arm maze, water maze, inhibitory avoidance, and contextual and cued fear conditioning paradigms. In the DH, PKMzeta inhibition selectively disrupted retention of information for spatial reference, but not spatial working memory in the radial arm maze, and precise, but not coarse spatial information in the water maze. Thus retention of accurate spatial, but not procedural and contextual information required PKMzeta activity. Similarly, PKMzeta inhibition in the hippocampus did not affect contextual information after fear conditioning. In contrast, PKMzeta inhibition in the BLA impaired retention of classical conditioned stimulus-unconditioned stimulus (CS-US associations for both contextual and auditory fear, as well as instrumentally conditioned inhibitory avoidance. PKMzeta inhibition had no effect on postshock freezing, indicating fear expression mediated by the BLA remained intact. Thus, persistent PKMzeta activity is a general mechanism for both appetitively and aversively motivated retention of specific, accurate learned information, but is not required for processing contextual, imprecise

  7. Comment on "Tequila, a neurotrypsin ortholog, regulates long-term memory formation in Drosophila".

    Sonderegger, Peter; Patthy, Laszlo

    2007-06-22

    Didelot et al. (Reports, 11 August 2006, p. 851) claimed that Drosophila Tequila (Teq) and human neurotrypsin are orthologs and concluded that deficient long-term memory after Teq inactivation indicates that neurotrypsin plays its essential role for human cognitive functions through a similar mechanism. Our analyses suggest that Teq and neurotrypsin are not orthologous, leading us to question their equivalent roles in higher brain function.

  8. mTORC2 controls actin polymerization required for consolidation of long-term memory.

    Huang, Wei; Zhu, Ping Jun; Zhang, Shixing; Zhou, Hongyi; Stoica, Loredana; Galiano, Mauricio; Krnjević, Krešimir; Roman, Gregg; Costa-Mattioli, Mauro

    2013-04-01

    A major goal of biomedical research is the identification of molecular and cellular mechanisms that underlie memory storage. Here we report a previously unknown signaling pathway that is necessary for the conversion from short- to long-term memory. The mammalian target of rapamycin (mTOR) complex 2 (mTORC2), which contains the regulatory protein Rictor (rapamycin-insensitive companion of mTOR), was discovered only recently and little is known about its function. We found that conditional deletion of Rictor in the postnatal murine forebrain greatly reduced mTORC2 activity and selectively impaired both long-term memory (LTM) and the late phase of hippocampal long-term potentiation (L-LTP). We also found a comparable impairment of LTM in dTORC2-deficient flies, highlighting the evolutionary conservation of this pathway. Actin polymerization was reduced in the hippocampus of mTORC2-deficient mice and its restoration rescued both L-LTP and LTM. Moreover, a compound that promoted mTORC2 activity converted early LTP into late LTP and enhanced LTM. Thus, mTORC2 could be a therapeutic target for the treatment of cognitive dysfunction.

  9. Tequila, a neurotrypsin ortholog, regulates long-term memory formation in Drosophila.

    Didelot, Gérard; Molinari, Florence; Tchénio, Paul; Comas, Daniel; Milhiet, Elodie; Munnich, Arnold; Colleaux, Laurence; Preat, Thomas

    2006-08-11

    Mutations in the human neurotrypsin gene are associated with autosomal recessive mental retardation. To further understand the pathophysiological consequences of the lack of this serine protease, we studied Tequila (Teq), the Drosophila neurotrypsin ortholog, using associative memory as a behavioral readout. We found that teq inactivation resulted in a long-term memory (LTM)-specific defect. After LTM conditioning of wild-type flies, teq expression transiently increased in the mushroom bodies. Moreover, specific inhibition of teq expression in adult mushroom bodies resulted in a reversible LTM defect. Hence, the Teq pathway is essential for information processing in Drosophila.

  10. Loganin enhances long-term potentiation and recovers scopolamine-induced learning and memory impairments.

    Hwang, Eun-Sang; Kim, Hyun-Bum; Lee, Seok; Kim, Min-Ji; Lee, Sung-Ok; Han, Seung-Moo; Maeng, Sungho; Park, Ji-Ho

    2017-03-15

    Although the incidence rate of dementia is rapidly growing in the aged population, therapeutic and preventive reagents are still suboptimal. Various model systems are used for the development of such reagents in which scopolamine is one of the favorable pharmacological tools widely applied. Loganin is a major iridoid glycoside obtained from Corni fructus (Cornusofficinalis et Zucc) and demonstrated to have anti-inflammatory, anti-tumor and osteoporosis prevention effects. It has also been found to attenuate Aβ-induced inflammatory reactions and ameliorate memory deficits induced by scopolamine. However, there has been limited information available on how loganin affects learning and memory both electrophysiologically and behaviorally. To assess its effect on learning and memory, we investigated the influence of acute loganin administration on long-term potentiation (LTP) using organotypic cultured hippocampal tissues. In addition, we measured the effects of loganin on the behavior performance related to avoidance memory, short-term spatial navigation memory and long-term spatial learning and memory in the passive avoidance, Y-maze, and Morris water maze learning paradigms, respectively. Loganin dose-dependently increased the total activity of fEPSP after high frequency stimulation and attenuated scopolamine-induced blockade of fEPSP in the hippocampal CA1 area. In accordance with these findings, loganin behaviorally attenuated scopolamine-induced shortening of step-through latency in the passive avoidance test, reduced the percent alternation in the Y-maze, and increased memory retention in the Morris water maze test. These results indicate that loganin can effectively block cholinergic muscarinic receptor blockade -induced deterioration of LTP and memory related behavioral performance. Based on these findings, loganin may aid in the prevention and treatment of Alzheimer's disease and learning and memory-deficit disorders in the future.

  11. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats.

    Vanessa Manchim Favaro

    Full Text Available Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show better performance in neuropsychological tests when tested in off-drug condition. This study evaluated the effects of long-term administration of ayahuasca on Morris water maze (MWM, fear conditioning and elevated plus maze (EPM performance in rats. Behavior tests started 48h after the end of treatment. Freeze-dried ayahuasca doses of 120, 240 and 480 mg/kg were used, with water as the control. Long-term administration consisted of a daily oral dose for 30 days by gavage. The behavioral data indicated that long-term ayahuasca administration did not affect the performance of animals in MWM and EPM tasks. However the dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning. The tone conditioned response was not affected after long-term administration. In addition, the increase in the contextual fear response was maintained during the repeated sessions several weeks after training. Taken together, these data showed that long-term ayahuasca administration in rats can interfere with the contextual association of emotional events, which is in agreement with the fact that the beverage activates brain areas related to these processes.

  12. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats

    Favaro, Vanessa Manchim; Yonamine, Maurício; Soares, Juliana Carlota Kramer; Oliveira, Maria Gabriela Menezes

    2015-01-01

    Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT) from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs) induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show better performance in neuropsychological tests when tested in off-drug condition. This study evaluated the effects of long-term administration of ayahuasca on Morris water maze (MWM), fear conditioning and elevated plus maze (EPM) performance in rats. Behavior tests started 48h after the end of treatment. Freeze-dried ayahuasca doses of 120, 240 and 480 mg/kg were used, with water as the control. Long-term administration consisted of a daily oral dose for 30 days by gavage. The behavioral data indicated that long-term ayahuasca administration did not affect the performance of animals in MWM and EPM tasks. However the dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning. The tone conditioned response was not affected after long-term administration. In addition, the increase in the contextual fear response was maintained during the repeated sessions several weeks after training. Taken together, these data showed that long-term ayahuasca administration in rats can interfere with the contextual association of emotional events, which is in agreement with the fact that the beverage activates brain areas related to these processes. PMID:26716991

  13. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats.

    Favaro, Vanessa Manchim; Yonamine, Maurício; Soares, Juliana Carlota Kramer; Oliveira, Maria Gabriela Menezes

    2015-01-01

    Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT) from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs) induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show better performance in neuropsychological tests when tested in off-drug condition. This study evaluated the effects of long-term administration of ayahuasca on Morris water maze (MWM), fear conditioning and elevated plus maze (EPM) performance in rats. Behavior tests started 48h after the end of treatment. Freeze-dried ayahuasca doses of 120, 240 and 480 mg/kg were used, with water as the control. Long-term administration consisted of a daily oral dose for 30 days by gavage. The behavioral data indicated that long-term ayahuasca administration did not affect the performance of animals in MWM and EPM tasks. However the dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning. The tone conditioned response was not affected after long-term administration. In addition, the increase in the contextual fear response was maintained during the repeated sessions several weeks after training. Taken together, these data showed that long-term ayahuasca administration in rats can interfere with the contextual association of emotional events, which is in agreement with the fact that the beverage activates brain areas related to these processes.

  14. Depletion of Serotonin Selectively Impairs Short-Term Memory without Affecting Long-Term Memory in Odor Learning in the Terrestrial Slug "Limax Valentianus"

    Santa, Tomofumi; Kirino, Yutaka; Watanabe, Satoshi; Shirahata, Takaaki; Tsunoda, Makoto

    2006-01-01

    The terrestrial slug "Limax" is able to acquire short-term and long-term memories during aversive odor-taste associative learning. We investigated the effect of the selective serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) on memory. Behavioral studies indicated that 5,7-DHT impaired short-term memory but not long-term memory. HPLC…

  15. Neuronal correlate of visual associative long-term memory in the primate temporal cortex

    Miyashita, Yasushi

    1988-10-01

    In human long-term memory, ideas and concepts become associated in the learning process1. No neuronal correlate for this cognitive function has so far been described, except that memory traces are thought to be localized in the cerebral cortex; the temporal lobe has been assigned as the site for visual experience because electric stimulation of this area results in imagery recall,2 and lesions produce deficits in visual recognition of objects3-9. We previously reported that in the anterior ventral temporal cortex of monkeys, individual neurons have a sustained activity that is highly selective for a few of the 100 coloured fractal patterns used in a visual working-memory task10. Here I report the development of this selectivity through repeated trials involving the working memory. The few patterns for which a neuron was conjointly selective were frequently related to each other through stimulus-stimulus association imposed during training. The results indicate that the selectivity acquired by these cells represents a neuronal correlate of the associative long-term memory of pictures.

  16. Neurotrophins play differential roles in short and long-term recognition memory.

    Callaghan, Charlotte K; Kelly, Aine M

    2013-09-01

    The neurotrophin family of proteins are believed to mediate various forms of synaptic plasticity in the adult brain. Here we have assessed the roles of these proteins in object recognition memory in the rat, using icv infusions of function-blocking antibodies or the tyrosine kinase antagonist, tyrphostin AG879, to block Trk receptors. We report that tyrphostin AG879 impairs both short-term and long-term recognition memory, indicating a requirement for Trk receptor activation in both processes. The effect of inhibition of each of the neurotrophins with activity-blocking neutralising antibodies was also tested. Treatment with anti-BDNF, anti-NGF or anti-NT4 had no effect on short-term memory, but blocked long-term recognition memory. Treatment with anti-NT3 had no effect on either process. We also assessed changes in expression of neurotrophins and their respective receptors in the hippocampus, dentate gyrus and perirhinal cortex over a 24 h period following training in the object recognition task. We observed time-dependent changes in expression of the Trk receptors and their ligands in the dentate gyrus and perirhinal cortex. The data are consistent with a pivotal role for neurotrophic factors in the expression of recognition memory.

  17. Long term memory for noise: evidence of robust encoding of very short temporal acoustic patterns.

    Jayalakshmi Viswanathan

    2016-11-01

    Full Text Available Recent research has demonstrated that humans are able to implicitly encode and retain repeating patterns in meaningless auditory noise. Our study aimed at testing the robustness of long-term implicit recognition memory for these learned patterns. Participants performed a cyclic/non-cyclic discrimination task, during which they were presented with either 1-s cyclic noises (CNs (the two halves of the noise were identical or 1-s plain random noises (Ns. Among CNs and Ns presented once, target CNs were implicitly presented multiple times within a block, and implicit recognition of these target CNs was tested 4 weeks later using a similar cyclic/non-cyclic discrimination task. Furthermore, robustness of implicit recognition memory was tested by presenting participants with looped (shifting the origin and scrambled (chopping sounds into 10- and 20-ms bits before shuffling versions of the target CNs. We found that participants had robust implicit recognition memory for learned noise patterns after 4 weeks, right from the first presentation. Additionally, this memory was remarkably resistant to acoustic transformations, such as looping and scrambling of the sounds. Finally, implicit recognition of sounds was dependent on participant’s discrimination performance during learning. Our findings suggest that meaningless temporal features as short as 10 ms can be implicitly stored in long-term auditory memory. Moreover, successful encoding and storage of such fine features may vary between participants, possibly depending on individual attention and auditory discrimination abilities.

  18. Fatty-acid binding proteins modulate sleep and enhance long-term memory consolidation in Drosophila.

    Jason R Gerstner

    Full Text Available Sleep is thought to be important for memory consolidation, since sleep deprivation has been shown to interfere with memory processing. However, the effects of augmenting sleep on memory formation are not well known, and testing the role of sleep in memory enhancement has been limited to pharmacological and behavioral approaches. Here we test the effect of overexpressing the brain-type fatty acid binding protein (Fabp7 on sleep and long-term memory (LTM formation in Drosophila melanogaster. Transgenic flies carrying the murine Fabp7 or the Drosophila homologue dFabp had reduced baseline sleep but normal LTM, while Fabp induction produced increases in both net sleep and LTM. We also define a post-training consolidation "window" that is sufficient for the observed Fabp-mediated memory enhancement. Since Fabp overexpression increases consolidated daytime sleep bouts, these data support a role for longer naps in improving memory and provide a novel role for lipid-binding proteins in regulating memory consolidation concurrently with changes in behavioral state.

  19. Extreme event return times in long-term memory processes near 1/f

    Blender, R.; Fraedrich, K.; Sienz, F.

    2008-07-01

    The distribution of extreme event return times and their correlations are analyzed in observed and simulated long-term memory (LTM) time series with 1/f power spectra. The analysis is based on tropical temperature and mixing ratio (specific humidity) time series from TOGA COARE with 1 min resolution and an approximate 1/f power spectrum. Extreme events are determined by Peak-Over-Threshold (POT) crossing. The Weibull distribution represents a reasonable fit to the return time distributions while the power-law predicted by the stretched exponential for 1/f deviates considerably. For a comparison and an analysis of the return time predictability, a very long simulated time series with an approximate 1/f spectrum is produced by a fractionally differenced (FD) process. This simulated data confirms the Weibull distribution (a power law can be excluded). The return time sequences show distinctly weaker long-term correlations than the original time series (correlation exponent γ≍0.56).

  20. A phenomenological memristor model for short-term/long-term memory

    Chen, Ling; Li, Chuandong; Huang, Tingwen; Ahmad, Hafiz Gulfam; Chen, Yiran

    2014-08-01

    Memristor is considered to be a natural electrical synapse because of its distinct memory property and nanoscale. In recent years, more and more similar behaviors are observed between memristors and biological synapse, e.g., short-term memory (STM) and long-term memory (LTM). The traditional mathematical models are unable to capture the new emerging behaviors. In this article, an updated phenomenological model based on the model of the Hewlett-Packard (HP) Labs has been proposed to capture such new behaviors. The new dynamical memristor model with an improved ion diffusion term can emulate the synapse behavior with forgetting effect, and exhibit the transformation between the STM and the LTM. Further, this model can be used in building new type of neural networks with forgetting ability like biological systems, and it is verified by our experiment with Hopfield neural network.

  1. Stress within a restricted time window selectively affects the persistence of long-term memory.

    Chang Yang

    Full Text Available The effects of stress on emotional memory are distinct and depend on the stages of memory. Memory undergoes consolidation and reconsolidation after acquisition and retrieval, respectively. Stress facilitates the consolidation but disrupts the reconsolidation of emotional memory. Previous research on the effects of stress on memory have focused on long-term memory (LTM formation (tested 24 h later, but the effects of stress on the persistence of LTM (tested at least 1 week later are unclear. Recent findings indicated that the persistence of LTM requires late-phase protein synthesis in the dorsal hippocampus. The present study investigated the effect of stress (i.e., cold water stress during the late phase after the acquisition and retrieval of contextual fear memory in rats. We found that stress and corticosterone administration during the late phase (12 h after acquisition, referred to as late consolidation, selectively enhanced the persistence of LTM, whereas stress during the late phase (12 h after retrieval, referred to as late reconsolidation, selectively disrupted the restabilized persistence of LTM. Moreover, the effects of stress on the persistence of LTM were blocked by the corticosterone synthesis inhibitor metyrapone, which was administered before stress, suggesting that the glucocorticoid system is involved in the effects of stress on the persistence of LTM. We conclude that stress within a restricted time window after acquisition or retrieval selectively affects the persistence of LTM and depends on the glucocorticoid system.

  2. Prediction analysis of long-term memory effect for calamity gray series

    CHEN; Zhaonan(CHEN; Chaonan); LI; Zongyang(LEE; Tzongye

    2004-01-01

    It is adequate to use the gray theory for modeling and forecasting short-term calamity series. The forecast of calamity gray series is equivalent to predicting an extraordinary event in nature. In order to look for the regularity, the calamity date series, created from the threshold for a fixed time-interval series, are studied. In this paper, the Hurst exponent is applied to defining the long-term memory effect of the simulated calamity series, and is tested for the feasibility of using it as pre-requisite information before the gray modeling and forecasting. Based on the fractional Brownian motion (fBm) model, the time series with a definite length or quantity of data are derived assuming that various kinds of memory effect exist. Different threshold values are defined to yield or to analogize the calamity date series that are required in the prediction of the gray calamity events. After case study, both of the simulated and real seismic data show that the Hurst exponents are greater than 0.5 and, therefore, indicate that the long-term memory effect exists. The correlation between the Hurst exponent and the gray modeling parameter, a, provides criteria for the classification of the forecast.

  3. Spatial coding of ordinal information in short- and long-term memory

    Veronique eGinsburg

    2015-01-01

    Full Text Available The processing of numerical information induces a spatial response bias: Faster responses to small numbers with the left hand and faster responses to large numbers with the right hand. Most theories agree that long-term representations underlie this so called SNARC effect (Spatial Numerical Association of Response Codes; Dehaene, Bossini, & Giraux, 1993. However, a spatial response bias was also observed with the activation of temporary position-space associations in working memory (ordinal position effect; van Dijck & Fias, 2011. Items belonging to the beginning of a memorized sequence are responded to faster with the left hand side while items at the end of the sequence are responded to faster with the right hand side. The theoretical possibility was put forward that the SNARC effect is an instance of the ordinal position effect, with the empirical consequence that the SNARC effect and the ordinal position effect cannot be observed simultaneously. In two experiments we falsify this claim by demonstrating that the SNARC effect and the ordinal position effect are not mutually exclusive. Consequently, this suggests that the SNARC effect and the ordinal position effect result from the activation of different representations. We conclude that spatial response biases can result from the activation of both pre-existing positions in long-term memory and from temporary space associations in working memory at the same time.

  4. Spatial coding of ordinal information in short- and long-term memory.

    Ginsburg, Véronique; Gevers, Wim

    2015-01-01

    The processing of numerical information induces a spatial response bias: Faster responses to small numbers with the left hand and faster responses to large numbers with the right hand. Most theories agree that long-term representations underlie this so called SNARC effect (Spatial Numerical Association of Response Codes; Dehaene et al., 1993). However, a spatial response bias was also observed with the activation of temporary position-space associations in working memory (ordinal position effect; van Dijck and Fias, 2011). Items belonging to the beginning of a memorized sequence are responded to faster with the left hand side while items at the end of the sequence are responded to faster with the right hand side. The theoretical possibility was put forward that the SNARC effect is an instance of the ordinal position effect, with the empirical consequence that the SNARC effect and the ordinal position effect cannot be observed simultaneously. In two experiments we falsify this claim by demonstrating that the SNARC effect and the ordinal position effect are not mutually exclusive. Consequently, this suggests that the SNARC effect and the ordinal position effect result from the activation of different representations. We conclude that spatial response biases can result from the activation of both pre-existing positions in long-term memory and from temporary space associations in working memory at the same time.

  5. Strategic search from long-term memory: an examination of semantic and autobiographical recall.

    Unsworth, Nash; Brewer, Gene A; Spillers, Gregory J

    2014-01-01

    Searching long-term memory is theoretically driven by both directed (search strategies) and random components. In the current study we conducted four experiments evaluating strategic search in semantic and autobiographical memory. Participants were required to generate either exemplars from the category of animals or the names of their friends for several minutes. Self-reported strategies suggested that participants typically relied on visualization strategies for both tasks and were less likely to rely on ordered strategies (e.g., alphabetic search). When participants were instructed to use particular strategies, the visualization strategy resulted in the highest levels of performance and the most efficient search, whereas ordered strategies resulted in the lowest levels of performance and fairly inefficient search. These results are consistent with the notion that retrieval from long-term memory is driven, in part, by search strategies employed by the individual, and that one particularly efficient strategy is to visualize various situational contexts that one has experienced in the past in order to constrain the search and generate the desired information.

  6. Chronic sleep deprivation differentially affects short and long-term operant memory in Aplysia.

    Krishnan, Harini C; Noakes, Eric J; Lyons, Lisa C

    2016-10-01

    The induction, formation and maintenance of memory represent dynamic processes modulated by multiple factors including the circadian clock and sleep. Chronic sleep restriction has become common in modern society due to occupational and social demands. Given the impact of cognitive impairments associated with sleep deprivation, there is a vital need for a simple animal model in which to study the interactions between chronic sleep deprivation and memory. We used the marine mollusk Aplysia californica, with its simple nervous system, nocturnal sleep pattern and well-characterized learning paradigms, to assess the effects of two chronic sleep restriction paradigms on short-term (STM) and long-term (LTM) associative memory. The effects of sleep deprivation on memory were evaluated using the operant learning paradigm, learning that food is inedible, in which the animal associates a specific netted seaweed with failed swallowing attempts. We found that two nights of 6h sleep deprivation occurring during the first or last half of the night inhibited both STM and LTM. Moreover, the impairment in STM persisted for more than 24h. A milder, prolonged sleep deprivation paradigm consisting of 3 consecutive nights of 4h sleep deprivation also blocked STM, but had no effect on LTM. These experiments highlight differences in the sensitivity of STM and LTM to chronic sleep deprivation. Moreover, these results establish Aplysia as a valid model for studying the interactions between chronic sleep deprivation and associative memory paving the way for future studies delineating the mechanisms through which sleep restriction affects memory formation.

  7. Acute stress does not impair long-term memory retrieval in older people.

    Pulopulos, Matias M; Almela, Mercedes; Hidalgo, Vanesa; Villada, Carolina; Puig-Perez, Sara; Salvador, Alicia

    2013-09-01

    Previous studies have shown that stress-induced cortisol increases impair memory retrieval in young people. This effect has not been studied in older people; however, some findings suggest that age-related changes in the brain can affect the relationships between acute stress, cortisol and memory in older people. Our aim was to investigate the effects of acute stress on long-term memory retrieval in healthy older people. To this end, 76 participants from 56 to 76 years old (38 men and 38 women) were exposed to an acute psychosocial stressor or a control task. After the stress/control task, the recall of pictures, words and stories learned the previous day was assessed. There were no differences in memory retrieval between the stress and control groups on any of the memory tasks. In addition, stress-induced cortisol response was not associated with memory retrieval. An age-related decrease in cortisol receptors and functional changes in the amygdala and hippocampus could underlie the differences observed between the results from this study and those found in studies performed with young people.

  8. Spatial, contextual and working memory are not affected by the absence of mossy fiber long-term potentiation and depression

    Hensbroek, R.A.; Kamal, A.; Baars, A.M.; Verhage, M.; Spruijt, B.M.

    2003-01-01

    The mossy fibers of the hippocampus display NMDA-receptor independent long-term plasticity. A number of studies addressed the role of mossy fiber long-term plasticity in memory, but have provided contrasting results. Here, we have exploited a genetic model, the rab3A null-mutant, which is characteri

  9. Boosting long-term memory via wakeful rest: intentional rehearsal is not necessary, consolidation is sufficient.

    Dewar, Michaela; Alber, Jessica; Cowan, Nelson; Della Sala, Sergio

    2014-01-01

    People perform better on tests of delayed free recall if learning is followed immediately by a short wakeful rest than by a short period of sensory stimulation. Animal and human work suggests that wakeful resting provides optimal conditions for the consolidation of recently acquired memories. However, an alternative account cannot be ruled out, namely that wakeful resting provides optimal conditions for intentional rehearsal of recently acquired memories, thus driving superior memory. Here we utilised non-recallable words to examine whether wakeful rest boosts long-term memory, even when new memories could not be rehearsed intentionally during the wakeful rest delay. The probing of non-recallable words requires a recognition paradigm. Therefore, we first established, via Experiment 1, that the rest-induced boost in memory observed via free recall can be replicated in a recognition paradigm, using concrete nouns. In Experiment 2, participants heard 30 non-recallable non-words, presented as 'foreign names in a bridge club abroad' and then either rested wakefully or played a visual spot-the-difference game for 10 minutes. Retention was probed via recognition at two time points, 15 minutes and 7 days after presentation. As in Experiment 1, wakeful rest boosted recognition significantly, and this boost was maintained for at least 7 days. Our results indicate that the enhancement of memory via wakeful rest is not dependent upon intentional rehearsal of learned material during the rest period. We thus conclude that consolidation is sufficient for this rest-induced memory boost to emerge. We propose that wakeful resting allows for superior memory consolidation, resulting in stronger and/or more veridical representations of experienced events which can be detected via tests of free recall and recognition.

  10. Boosting long-term memory via wakeful rest: intentional rehearsal is not necessary, consolidation is sufficient.

    Michaela Dewar

    Full Text Available People perform better on tests of delayed free recall if learning is followed immediately by a short wakeful rest than by a short period of sensory stimulation. Animal and human work suggests that wakeful resting provides optimal conditions for the consolidation of recently acquired memories. However, an alternative account cannot be ruled out, namely that wakeful resting provides optimal conditions for intentional rehearsal of recently acquired memories, thus driving superior memory. Here we utilised non-recallable words to examine whether wakeful rest boosts long-term memory, even when new memories could not be rehearsed intentionally during the wakeful rest delay. The probing of non-recallable words requires a recognition paradigm. Therefore, we first established, via Experiment 1, that the rest-induced boost in memory observed via free recall can be replicated in a recognition paradigm, using concrete nouns. In Experiment 2, participants heard 30 non-recallable non-words, presented as 'foreign names in a bridge club abroad' and then either rested wakefully or played a visual spot-the-difference game for 10 minutes. Retention was probed via recognition at two time points, 15 minutes and 7 days after presentation. As in Experiment 1, wakeful rest boosted recognition significantly, and this boost was maintained for at least 7 days. Our results indicate that the enhancement of memory via wakeful rest is not dependent upon intentional rehearsal of learned material during the rest period. We thus conclude that consolidation is sufficient for this rest-induced memory boost to emerge. We propose that wakeful resting allows for superior memory consolidation, resulting in stronger and/or more veridical representations of experienced events which can be detected via tests of free recall and recognition.

  11. Attention, Working Memory, and Long-Term Memory in Multimedia Learning: An Integrated Perspective Based on Process Models of Working Memory

    Schweppe, Judith; Rummer, Ralf

    2014-01-01

    Cognitive models of multimedia learning such as the Cognitive Theory of Multimedia Learning (Mayer 2009) or the Cognitive Load Theory (Sweller 1999) are based on different cognitive models of working memory (e.g., Baddeley 1986) and long-term memory. The current paper describes a working memory model that has recently gained popularity in basic…

  12. Bound feature combinations in visual short-term memory are fragile but influence long-term learning

    R.H. Logie; J.R. Brockmole; A.R.E. Vandenbroucke

    2009-01-01

    We explored whether individual features and bindings between those features in VSTM tasks are completely lost from trial to trial or whether residual memory traces for these features and bindings are retained in long-term memory. Memory for arrays of coloured shapes was assessed using change detecti

  13. Fornix deep brain stimulation induced long-term spatial memory independent of hippocampal neurogenesis.

    Hescham, Sarah; Temel, Yasin; Schipper, Sandra; Lagiere, Mélanie; Schönfeld, Lisa-Maria; Blokland, Arjan; Jahanshahi, Ali

    2017-03-01

    Deep brain stimulation (DBS) is an established symptomatic treatment modality for movement disorders and constitutes an emerging therapeutic approach for the treatment of memory impairment. In line with this, fornix DBS has shown to ameliorate cognitive decline associated with dementia. Nonetheless, mechanisms mediating clinical effects in demented patients or patients with other neurological disorders are largely unknown. There is evidence that DBS is able to modulate neurophysiological activity in targeted brain regions. We therefore hypothesized that DBS might be able to influence cognitive function via activity-dependent regulation of hippocampal neurogenesis. Using stimulation parameters, which were validated to restore memory loss in a previous behavioral study, we here assessed long-term effects of fornix DBS. To do so, we injected the thymidine analog, 5-bromo-2'-deoxyuridine (BrdU), after DBS and perfused the animals 6.5 weeks later. A week prior to perfusion, memory performance was assessed in the water maze. We found that acute stimulation of the fornix improved spatial memory performance in the water maze when the probe trial was performed 1 h after the last training session. However, no evidence for stimulation-induced neurogenesis was found in fornix DBS rats when compared to sham. Our results suggest that fornix DBS improves memory functions independent of hippocampal neurogenesis, possibly through other mechanisms such as synaptic plasticity and acute neurotransmitter release.

  14. Astrocytic β2-adrenergic receptors mediate hippocampal long-term memory consolidation

    Gao, Virginia

    2016-07-12

    Emotionally relevant experiences form strong and long-lasting memories by critically engaging the stress hormone/neurotransmitter noradrenaline, which mediates and modulates the consolidation of these memories. Noradrenaline acts through adrenergic receptors (ARs), of which β2- Adrenergic receptors (βARs) are of particular importance. The differential anatomical and cellular distribution of βAR subtypes in the brain suggests that they play distinct roles in memory processing, although much about their specific contributions and mechanisms of action remains to be understood. Here we show that astrocytic rather than neuronal β2ARs in the hippocampus play a key role in the consolidation of a fear-based contextual memory. These hippocampal β2ARs, but not β1ARs, are coupled to the training-dependent release of lactate from astrocytes, which is necessary for long- Term memory formation and for underlying molecular changes. This key metabolic role of astrocytic β2ARs may represent a novel target mechanism for stress-related psychopathologies and neurodegeneration.

  15. Requirement for nuclear calcium signaling in Drosophila long-term memory.

    Weislogel, Jan-Marek; Bengtson, C Peter; Müller, Michaela K; Hörtzsch, Jan N; Bujard, Martina; Schuster, Christoph M; Bading, Hilmar

    2013-05-07

    Calcium is used throughout evolution as an intracellular signal transducer. In the mammalian central nervous system, calcium mediates the dialogue between the synapse and the nucleus that is required for transcription-dependent persistent neuronal adaptations. A role for nuclear calcium signaling in similar processes in the invertebrate brain has yet to be investigated. Here, we show by in vivo calcium imaging of adult brain neurons of the fruit fly Drosophila melanogaster, that electrical foot shocks used in olfactory avoidance conditioning evoked transient increases in cytosolic and nuclear calcium concentrations in neurons. These calcium signals were detected in Kenyon cells of the flies' mushroom bodies, which are sites of learning and memory related to smell. Acute blockade of nuclear calcium signaling during conditioning selectively and reversibly abolished the formation of long-term olfactory avoidance memory, whereas short-term, middle-term, or anesthesia-resistant olfactory memory remained unaffected. Thus, nuclear calcium signaling is required in flies for the progression of memories from labile to transcription-dependent long-lasting forms. These results identify nuclear calcium as an evolutionarily conserved signal needed in both invertebrate and vertebrate brains for transcription-dependent memory consolidation.

  16. Parametric and genetic analysis of Drosophila appetitive long-term memory and sugar motivation.

    Colomb, J; Kaiser, L; Chabaud, M-A; Preat, T

    2009-06-01

    Distinct forms of memory can be highlighted using different training protocols. In Drosophila olfactory aversive learning, one conditioning session triggers memory formation independently of protein synthesis, while five spaced conditioning sessions lead to the formation of long-term memory (LTM), a long-lasting memory dependent on de novo protein synthesis. In contrast, one session of odour-sugar association appeared sufficient for the fly to form LTM. We designed and tuned an apparatus that facilitates repeated discriminative conditioning by alternate presentations of two odours, one being associated with sugar, as well as a new paradigm to test sugar responsiveness (SR). Our results show that both SR and short-term memory (STM) scores increase with starvation length before conditioning. The protein dependency of appetitive LTM is independent of the repetition and the spacing of training sessions, on the starvation duration and on the strength of the unconditioned stimulus. In contrast to a recent report, our test measures an abnormal SR of radish mutant flies, which might initiate their STM and LTM phenotypes. In addition, our work shows that crammer and tequila mutants, which are deficient for aversive LTM, present both an SR and an appetitive STM defect. Using the MB247-P[switch] system, we further show that tequila is required in the adult mushroom bodies for normal sugar motivation.

  17. Long-term memory in the Irish market (ISEQ): evidence from wavelet analysis

    Sharkasi, A; Crane, M; Sharkasi, Adel; Ruskin, Heather J.; Crane, Martin

    2006-01-01

    Researchers have used many different methods to detect the possibility of long-term dependence (long memory) in stock market returns, but evidence is in general mixed. In this paper, three different tests, (namely Rescaled Range (R/S), its modified form, and the semi-parametric method (GPH)), in addition to a new approach using the discrete wavelet transform, (DWT), have been applied to the daily returns of five Irish Stock Exchange (ISEQ) indices. These methods have also been applied to the volatility measures (namely absolute and squared returns). The aim is to investigate the existence of long-term memory properties. The indices are Overall, Financial, General, Small Cap and ITEQ and the results of these approaches show that there is no evidence of long-range dependence in the returns themselves, while there is strong evidence for such dependence in the squared and absolute returns. Moreover, the discrete wavelet transform (DWT) provides additional insight on the series breakdown. In particular, in compari...

  18. Helping students succeed by helping them improve their long-term memory

    Zettili, Nouredine; Boukahil, A.

    2005-04-01

    In this work, we focus on one of the most useful techniques of efficient study habits: How to improve long-term memory. We show that if a student carries a number of recalling sessions of the material studied and if he/she carries them at specific times, the student will be able to retain this material for a long time and hence be prepared for the exams. We argue that a student who conscientiously uses the proper techniques of efficient study habits will be able to achieve higher results than the student who does not. Moreover, a student equipped with the proper study skills will spend much less time to learn a subject than a student who has no effective study habits. After providing a summary of the most essential personal skills needed to be a successful student--concentration skills, how to take notes in class, how to prepare for and take exams---we give an extensive presentation on the techniques of improving long-term memory.

  19. Correlating learning and memory improvements to long-term potentiation in patients with brain injury

    Xingfu Peng; Qian Yu

    2008-01-01

    BACKGROUND:Brain injury patients often exhibit learning and memory functional deficits.Long-term potentiation(LTP)is a representative index for studying learning and memory cellular models; the LTP index correlates to neural plasticity. OBJECTIVE:This study was designed to investigate correlations of learning and memory functions to LTP in brain injury patients,and to summarize the research advancements in mechanisms underlying brain functional improvements after rehabilitation intervention. RETRIEVAL STRATEGY:Using the terms "brain injuries,rehabilitation,learning and memory,long-term potentiation",manuscripts that were published from 2000-2007 were retrieved from the PubMed database.At the same time,manuscripts published from 2000-2007 were also retrieved from the Database of Chinese Scientific and Technical Periodicals with the same terms in the Chinese language.A total of 64 manuscripts were obtained and primarily screened.Inclusion criteria:studies on learning and memory,as well as LTP in brain injury patients,and studies focused on the effects of rehabilitation intervention on the two indices; studies that were recently published or in high-impact journals.Exclusion criteria:repetitive studies.LITERATURE EVALUATION:The included manuscripts primarily focused on correlations between learning and memory and LTP,the effects of brain injury on learning and memory,as well as LTP,and the effects of rehabilitation intervention on learning and memory after brain injury.The included 39 manuscripts were clinical,basic experimental,or review studies. DATA SYNTHESIS:Learning and memory closely correlates to LTP.The neurobiological basis of learning and memory is central nervous system plasticity,which involves neural networks,neural circuits,and synaptic connections,in particular,synaptic plasticity.LTP is considered to be an ideal model for studying synaptic plasticity,and it is also a classic model for studying neural plasticity of learning and memory.Brain injury

  20. Animal model of methylphenidate's long-term memory-enhancing effects.

    Carmack, Stephanie A; Howell, Kristin K; Rasaei, Kleou; Reas, Emilie T; Anagnostaras, Stephan G

    2014-01-16

    Methylphenidate (MPH), introduced more than 60 years ago, accounts for two-thirds of current prescriptions for attention deficit hyperactivity disorder (ADHD). Although many studies have modeled MPH's effect on executive function, almost none have directly modeled its effect on long-term memory (LTM), even though improvement in LTM is a critical target of therapeutic intervention in ADHD. We examined the effects of a wide range of doses of MPH (0.01-10 mg/kg, i.p.) on Pavlovian fear learning, a leading model of memory. MPH's effects were then compared to those of atomoxetine (0.1-10 mg/kg, i.p.), bupropion (0.5-20 mg/kg, i.p.), and citalopram (0.01-10 mg/kg, i.p.). At low, clinically relevant doses, MPH enhanced fear memory; at high doses it impaired memory. MPH's memory-enhancing effects were not confounded by its effects on locomotion or anxiety. Further, MPH-induced memory enhancement seemed to require both dopamine and norepinephrine transporter inhibition. Finally, the addictive potential of MPH (1 mg/kg and 10 mg/kg) was compared to those of two other psychostimulants, amphetamine (0.005 mg/kg and 1.5 mg/kg) and cocaine (0.15 mg/kg and 15 mg/kg), using a conditioned place preference and behavioral sensitization paradigm. We found that memory-enhancing effects of psychostimulants observed at low doses are readily dissociable from their reinforcing and locomotor activating effects at high doses. Together, our data suggest that fear conditioning will be an especially fruitful platform for modeling the effects of psychostimulants on LTM in drug development.

  1. Evaluation of the measurement uncertainty in automated long-term sampling of PCDD/PCDFs.

    Vicaretti, M; D'Emilia, G; Mosca, S; Guerriero, E; Rotatori, M

    2013-12-01

    Since the publication of the first version of European standard EN-1948 in 1996, long-term sampling equipment has been improved to a high standard for the sampling and analysis of polychlorodibenzo-p-dioxin (PCDD)/polychlorodibenzofuran (PCDF) emissions from industrial sources. The current automated PCDD/PCDF sampling systems enable to extend the measurement time from 6-8 h to 15-30 days in order to have data values better representative of the real pollutant emission of the plant in the long period. EN-1948:2006 is still the European technical reference standard for the determination of PCDD/PCDF from stationary source emissions. In this paper, a methodology to estimate the measurement uncertainty of long-term automated sampling is presented. The methodology has been tested on a set of high concentration sampling data resulting from a specific experience; it is proposed with the intent that it is to be applied on further similar studies and generalized. A comparison between short-term sampling data resulting from manual and automated parallel measurements has been considered also in order to verify the feasibility and usefulness of automated systems and to establish correlations between results of the two methods to use a manual method for calibration of automatic long-term one. The uncertainty components of the manual method are analyzed, following the requirements of EN-1948-3:2006, allowing to have a preliminary evaluation of the corresponding uncertainty components of the automated system. Then, a comparison between experimental data coming from parallel sampling campaigns carried out in short- and long-term sampling periods is realized. Long-term sampling is more reliable to monitor PCDD/PCDF emissions than occasional short-term sampling. Automated sampling systems can assure very useful emission data both in short and long sampling periods. Despite this, due to the different application of the long-term sampling systems, the automated results could not be

  2. The limitations of our knowledge about social influences on memories of sexual abuse over the long-term

    Koppel, Jonathan Mark; Berntsen, Dorthe

    2015-01-01

    Fagin, Cyr, and Hirst provide an informed and insightful application of the social memory literature to the important question of how memories of sexual abuse may be re-shaped, both over the short term and long term, by communication with others, as well as with oneself. In the following commentary......, we outline several respects in which we believe that the application of this literature to memories of sexual abuse, particularly over the long term, is still open to debate. In particular, we focus on induced forgetting and social contagion for such memories, as well as the application of the social...

  3. Unforgettable film music: The role of emotion in episodic long-term memory for music

    Altenmüller Eckart O

    2008-05-01

    Full Text Available Abstract Background Specific pieces of music can elicit strong emotions in listeners and, possibly in connection with these emotions, can be remembered even years later. However, episodic memory for emotional music compared with less emotional music has not yet been examined. We investigated whether emotional music is remembered better than less emotional music. Also, we examined the influence of musical structure on memory performance. Results Recognition of 40 musical excerpts was investigated as a function of arousal, valence, and emotional intensity ratings of the music. In the first session the participants judged valence and arousal of the musical pieces. One week later, participants listened to the 40 old and 40 new musical excerpts randomly interspersed and were asked to make an old/new decision as well as to indicate arousal and valence of the pieces. Musical pieces that were rated as very positive were recognized significantly better. Conclusion Musical excerpts rated as very positive are remembered better. Valence seems to be an important modulator of episodic long-term memory for music. Evidently, strong emotions related to the musical experience facilitate memory formation and retrieval.

  4. ADRA2B deletion variant influences time-dependent effects of pre-learning stress on long-term memory.

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

    2017-02-22

    Extensive work over the past few decades has shown that certain genetic variations interact with life events to confer increased susceptibility for the development of psychological disorders. The deletion variant of the ADRA2B gene, which has been associated with enhanced emotional memory and heightened amygdala responses to emotional stimuli, might confer increased susceptibility for the development of post-traumatic stress disorder (PTSD) or related phenotypes by increasing the likelihood of traumatic memory formation. Thus, we examined whether this genetic variant would predict stress effects on learning and memory in a non-clinical sample. Two hundred and thirty-five individuals were exposed to the socially evaluated cold pressor test or a control condition immediately or 30min prior to learning a list of words that varied in emotional valence and arousal level. Participants' memory for the words was tested immediately (recall) and 24h after learning (recall and recognition), and saliva samples were collected to genotype participants for the ADRA2B deletion variant. Results showed that stress administered immediately before learning selectively enhanced long-term recall in deletion carriers. Stress administered 30min before learning impaired recognition memory in male deletion carriers, while enhancing recognition memory in female deletion carriers. These findings provide additional evidence to support the idea that ADRA2B deletion variant carriers retain a sensitized stress response system, which results in amplified effects of stress on learning and memory. The accumulating evidence regarding this genetic variant implicates it as a susceptibility factor for traumatic memory formation and PTSD-related phenotypes.

  5. Differential role of entorhinal and hippocampal nerve growth factor in short- and long-term memory modulation.

    Walz, R; Roesler, R; Reinke, A; Martins, M R; Quevedo, J; Izquierdo, I

    2005-01-01

    We studied the effects of infusion of nerve growth factor (NGF) into the hippocampus and entorhinal cortex of male Wistar rats (250-300 g, N = 11-13 per group) on inhibitory avoidance retention. In order to evaluate the modulation of entorhinal and hippocampal NGF in short- and long-term memory, animals were implanted with cannulae in the CA1 area of the dorsal hippocampus or entorhinal cortex and trained in one-trial step-down inhibitory avoidance (foot shock, 0.4 mA). Retention tests were carried out 1.5 h or 24 h after training to measure short- and long-term memory, respectively. Immediately after training, rats received 5 microl NGF (0.05, 0.5 or 5.0 ng) or saline per side into the CA1 area and entorhinal cortex. The correct position of the cannulae was confirmed by histological analysis. The highest dose of NGF (5.0 ng) into the hippocampus blocked short-term memory (P long-term memory. NGF administration into the entorhinal cortex improved long-term memory at the dose of 5.0 ng (P short-term memory. Taken as a whole, our results suggest a differential modulation by entorhinal and hippocampal NGF of short- and long-term memory.

  6. Protein degradation and protein synthesis in long-term memory formation

    Timothy J Jarome

    2014-06-01

    Full Text Available Long-term memory (LTM formation requires transient changes in the activity of intracellular signaling cascades that are thought to regulate new gene transcription and de novo protein synthesis in the brain. Consistent with this, protein synthesis inhibitors impair LTM for a variety of behavioral tasks when infused into the brain around the time of training or following memory retrieval, suggesting that protein synthesis is a critical step in LTM storage in the brain. However, evidence suggests that protein degradation mediated by the ubiquitin-proteasome system may also be a critical regulator of LTM formation and stability following retrieval. This requirement for increased protein degradation has been shown in the same brain regions in which protein synthesis is required for LTM storage. Additionally, increases in the phosphorylation of proteins involved in translational control parallel increases in protein polyubiquitination and the increased demand for protein degradation is regulated by intracellular signaling molecules thought to regulate protein synthesis during LTM formation. In some cases inhibiting proteasome activity can rescue memory impairments that result from pharmacological blockade of protein synthesis, suggesting that protein degradation may control the requirement for protein synthesis during the memory storage process. Results such as these suggest that protein degradation and synthesis are both critical for LTM formation and may interact to properly consolidate and store memories in the brain. Here, we review the evidence implicating protein synthesis and degradation in LTM storage and highlight the areas of overlap between these two opposing processes. We also discuss evidence suggesting these two processes may interact to properly form and store memories. LTM storage likely requires a coordinated regulation between protein degradation and synthesis at multiple sites in the mammalian brain.

  7. Errors in nonword repetition: bridging short- and long-term memory

    F.H. Santos

    2006-03-01

    Full Text Available According to the working memory model, the phonological loop is the component of working memory specialized in processing and manipulating limited amounts of speech-based information. The Children's Test of Nonword Repetition (CNRep is a suitable measure of phonological short-term memory for English-speaking children, which was validated by the Brazilian Children's Test of Pseudoword Repetition (BCPR as a Portuguese-language version. The objectives of the present study were: i to investigate developmental aspects of the phonological memory processing by error analysis in the nonword repetition task, and ii to examine phoneme (substitution, omission and addition and order (migration errors made in the BCPR by 180 normal Brazilian children of both sexes aged 4-10, from preschool to 4th grade. The dominant error was substitution [F(3,525 = 180.47; P < 0.0001]. The performance was age-related [F(4,175 = 14.53; P < 0.0001]. The length effect, i.e., more errors in long than in short items, was observed [F(3,519 = 108.36; P < 0.0001]. In 5-syllable pseudowords, errors occurred mainly in the middle of the stimuli, before the syllabic stress [F(4,16 = 6.03; P = 0.003]; substitutions appeared more at the end of the stimuli, after the stress [F(12,48 = 2.27; P = 0.02]. In conclusion, the BCPR error analysis supports the idea that phonological loop capacity is relatively constant during development, although school learning increases the efficiency of this system. Moreover, there are indications that long-term memory contributes to holding memory trace. The findings were discussed in terms of distinctiveness, clustering and redintegration hypotheses.

  8. Genetic enhancement of memory and long-term potentiation but not CA1 long-term depression in NR2B transgenic rats.

    Deheng Wang

    Full Text Available One major theory in learning and memory posits that the NR2B gene is a universal genetic factor that acts as rate-limiting molecule in controlling the optimal NMDA receptor's coincidence-detection property and subsequent learning and memory function across multiple animal species. If so, can memory function be enhanced via transgenic overexpression of NR2B in another species other than the previously reported mouse species? To examine these crucial issues, we generated transgenic rats in which NR2B is overexpressed in the cortex and hippocampus and investigated the role of NR2B gene in NMDA receptor-mediated synaptic plasticity and memory functions by combining electrophysiological technique with behavioral measurements. We found that overexpression of the NR2B subunit had no effect on CA1-LTD, but rather resulted in enhanced CA1-LTP and improved memory performances in novel object recognition test, spatial water maze, and delayed-to-nonmatch working memory test. Our slices recordings using NR2A- and NR2B-selective antagonists further demonstrate that the larger LTP in transgenic hippocampal slices was due to contribution from the increased NR2B-containing NMDARs. Therefore, our genetic experiments suggest that NR2B at CA1 synapses is not designated as a rate-limiting factor for the induction of long-term synaptic depression, but rather plays a crucial role in initiating the synaptic potentiation. Moreover, our studies provide strong evidence that the NR2B subunit represents a universal rate-limiting molecule for gating NMDA receptor's optimal coincidence-detection property and for enhancing memory function in adulthood across multiple mammalian species.

  9. Delayed emergence of effects of memory-enhancing drugs: implications for the dynamics of long-term memory.

    Mondadori, C; Hengerer, B; Ducret, T; Borkowski, J

    1994-01-01

    Many theories of memory postulate that processing of information outlasts the learning situation and involves several different physiological substrates. If such physiologically distinct mechanisms or stages of memory do in fact exist, they should be differentially affected by particular experimental manipulations. Accordingly, a selective improvement of the processes underlying short-term memory should be detectable only while the information is encoded in the short-term mode, and a selective influence on long-term memory should be detectable only from the moment when memory is based on the long-term trace. Our comparative study of the time course of the effects of the cholinergic agonist arecoline, the gamma-aminobutyric acid type B receptor antagonist CGP 36742, the angiotensin-converting enzyme inhibitor captopril, and the nootropic oxiracetam, four substances with completely different primary sites of action, show that the memory-enhancing effects consistently come into evidence no sooner than 16-24 h after the learning trial. On the one hand, this finding suggests that all these substances act by way of the same type of mechanism; on the other hand, it demonstrates that the substrate modulated by the compounds forms the basis of memory only after 16-24 h. From the observation that animals also show clear signs of retention during the first 16 h--i.e., before the effects of the substances are measurable--it can be inferred that retention during this time is mediated by other mechanisms that are not influenced by any of the substances. Images PMID:8134347

  10. Reward signal in a recurrent circuit drives appetitive long-term memory formation.

    Ichinose, Toshiharu; Aso, Yoshinori; Yamagata, Nobuhiro; Abe, Ayako; Rubin, Gerald M; Tanimoto, Hiromu

    2015-11-17

    Dopamine signals reward in animal brains. A single presentation of a sugar reward to Drosophila activates distinct subsets of dopamine neurons that independently induce short- and long-term olfactory memories (STM and LTM, respectively). In this study, we show that a recurrent reward circuit underlies the formation and consolidation of LTM. This feedback circuit is composed of a single class of reward-signaling dopamine neurons (PAM-α1) projecting to a restricted region of the mushroom body (MB), and a specific MB output cell type, MBON-α1, whose dendrites arborize that same MB compartment. Both MBON-α1 and PAM-α1 neurons are required during the acquisition and consolidation of appetitive LTM. MBON-α1 additionally mediates the retrieval of LTM, which is dependent on the dopamine receptor signaling in the MB α/β neurons. Our results suggest that a reward signal transforms a nascent memory trace into a stable LTM using a feedback circuit at the cost of memory specificity.

  11. Fasting launches CRTC to facilitate long-term memory formation in Drosophila.

    Hirano, Yukinori; Masuda, Tomoko; Naganos, Shintaro; Matsuno, Motomi; Ueno, Kohei; Miyashita, Tomoyuki; Horiuchi, Junjiro; Saitoe, Minoru

    2013-01-25

    Canonical aversive long-term memory (LTM) formation in Drosophila requires multiple spaced trainings, whereas appetitive LTM can be formed after a single training. Appetitive LTM requires fasting prior to training, which increases motivation for food intake. However, we found that fasting facilitated LTM formation in general; aversive LTM formation also occurred after single-cycle training when mild fasting was applied before training. Both fasting-dependent LTM (fLTM) and spaced training-dependent LTM (spLTM) required protein synthesis and cyclic adenosine monophosphate response element-binding protein (CREB) activity. However, spLTM required CREB activity in two neural populations--mushroom body and DAL neurons--whereas fLTM required CREB activity only in mushroom body neurons. fLTM uses the CREB coactivator CRTC, whereas spLTM uses the coactivator CBP. Thus, flies use distinct LTM machinery depending on their hunger state.

  12. Interdisciplinary Approach to the Mental Lexicon: Neural Network and Text Extraction From Long-term Memory

    Vardan G. Arutyunyan

    2013-01-01

    Full Text Available The paper touches upon the principles of mental lexicon organization in the light of recent research in psycho- and neurolinguistics. As a focal point of discussion two main approaches to mental lexicon functioning are considered: modular or dual-system approach, developed within generativism and opposite single-system approach, representatives of which are the connectionists and supporters of network models. The paper is an endeavor towards advocating the viewpoint that mental lexicon is complex psychological organization based upon specific composition of neural network. In this regard, the paper further elaborates on the matter of storing text in human mental space and introduces a model of text extraction from long-term memory. Based upon data available, the author develops a methodology of modeling structures of knowledge representation in the systems of artificial intelligence.

  13. Long-term memory in experiments and numerical simulations of hydrodynamic and magnetohydrodynamic turbulence.

    Mininni, P; Dmitruk, P; Odier, P; Pinton, J-F; Plihon, N; Verhille, G; Volk, R; Bourgoin, M

    2014-05-01

    We analyze time series stemming from experiments and direct numerical simulations of hydrodynamic and magnetohydrodynamic turbulence. Simulations are done in periodic boxes, but with a volumetric forcing chosen to mimic the geometry of the flow in the experiments, the von Kármán swirling flow between two counterrotating impellers. Parameters in the simulations are chosen to (within computational limitations) allow comparisons between the experiments and the numerical results. Conducting fluids are considered in all cases. Two different configurations are considered: a case with a weak externally imposed magnetic field and a case with self-sustained magnetic fields. Evidence of long-term memory and 1/f noise is observed in experiments and simulations, in the case with weak magnetic field associated with the hydrodynamic behavior of the shear layer in the von Kármán flow, and in the dynamo case associated with slow magnetohydrodynamic behavior of the large-scale magnetic field.

  14. The involvement of long-term serial-order memory in reading development: A longitudinal study.

    Bogaerts, Louisa; Szmalec, Arnaud; De Maeyer, Marjolijn; Page, Mike P A; Duyck, Wouter

    2016-05-01

    Recent findings suggest that Hebb repetition learning-a paradigmatic example of long-term serial-order learning-is impaired in adults with dyslexia. The current study further investigated the link between serial-order learning and reading using a longitudinal developmental design. With this aim, verbal and visual Hebb repetition learning performance and reading skills were assessed in 96 Dutch-speaking children who we followed from first through second grade of primary school. We observed a positive association between order learning capacities and reading ability as well as weaker Hebb learning performance in early readers with poor reading skills even at the onset of reading instruction. Hebb learning further predicted individual differences in later (nonword) reading skills. Finally, Hebb learning was shown to explain a significant part of the variance in reading performance above and beyond phonological awareness. These findings highlight the role of serial-order memory in reading ability.

  15. Differentially expressed genes linked to natural variation in long-term memory formation in Cotesia parasitic wasps

    Joke J. F. A. Van Vugt

    2015-09-01

    Full Text Available Even though learning and memory are universal traits in the Animal Kingdom, closely related species reveal substantial variation in learning rate and memory dynamics. To determine the genetic background of this natural variation, we studied two congeneric parasitic wasp species, Cotesia glomerata and C. rubecula, which lay their eggs in caterpillars of the large and small cabbage white butterfly. A successful egg laying event serves as an unconditioned stimulus in a classical conditioning paradigm, where plant odors become associated to the encounter of a suitable host caterpillar. Depending on the host species, the number of conditioning trials and the parasitic wasp species, three different types of transcription-dependent long-term memory (LTM and one type of transcription-independent, anesthesia-resistant memory (ARM can be distinguished. To identify transcripts underlying these differences in memory formation, we isolated mRNA from parasitic wasp heads at three different time points between induction and consolidation of each of the four memory types, and for each sample three biological replicates, where after strand-specific paired-end 100 bp deep sequencing. Transcriptomes were assembled de novo and differential expression was determined for each memory type and time point after conditioning, compared to unconditioned wasps. Most differentially expressed (DE genes and antisense transcripts were only DE in one of the LTM types. Among the DE genes that were DE in two or more LTM types, were many protein kinases and phosphatases, small GTPases, receptors and ion channels. Some genes were DE in opposing directions between any of the LTM memory types and ARM, suggesting that ARM in Cotesia requires the transcription of genes inhibiting LTM or vice versa. We discuss our findings in the context of neuronal functioning, including RNA splicing and transport, epigenetic regulation, neurotransmitter/peptide synthesis and antisense transcription. In

  16. Four-month-old infants' long-term memory for a stressful social event.

    Montirosso, Rosario; Tronick, Ed; Morandi, Francesco; Ciceri, Francesca; Borgatti, Renato

    2013-01-01

    Infants clearly show an early capacity for memory for inanimate emotionally neutral events. However, their memory for social stress events has received far less attention. The aim of the study was to investigate infants' memory for a stressful social event (i.e., maternal unresponsiveness during the Still-Face paradigm) after a 15-day recall interval using changes in behavioral responses and salivary post-stress cortisol reactivity as measures of memory. Thirty-seven infants were exposed to social stress two times (experimental condition); the first time when they were 4 months of age and second exposure after a 2 week interval. Infants in the control condition (N = 37) were exposed to social stress just one time, at the age corresponding to the second exposure for infants in the experimental condition (4 months plus 2 weeks). Given individual differences in infants' reactivity to social stress events, we categorized infants as increasers or decreasers based on their cortisol reactivity after their initial exposure to the stress of the maternal still-face. Infants in the experimental condition, both increasers and decreasers, showed a significant change in cortisol response after the second exposure to the maternal still-face, though change was different for each reactivity group. In contrast, age-matched infants with no prior exposure to the maternal still-face showed similar post-stress cortisol reactivity to the reactivity of the experimental infants at their first exposure. There were no behavioral differences between increasers and decreasers during the Still-Face paradigm and exposures to the social stress. Thus differences between the experimental and control groups' post-stress cortisol reactivity was associated with the experimental group having previous experience with the social stress. These findings indicate long-term memory for social stress in infants as young as 4 months of age.

  17. Four-month-old infants' long-term memory for a stressful social event.

    Rosario Montirosso

    Full Text Available Infants clearly show an early capacity for memory for inanimate emotionally neutral events. However, their memory for social stress events has received far less attention. The aim of the study was to investigate infants' memory for a stressful social event (i.e., maternal unresponsiveness during the Still-Face paradigm after a 15-day recall interval using changes in behavioral responses and salivary post-stress cortisol reactivity as measures of memory. Thirty-seven infants were exposed to social stress two times (experimental condition; the first time when they were 4 months of age and second exposure after a 2 week interval. Infants in the control condition (N = 37 were exposed to social stress just one time, at the age corresponding to the second exposure for infants in the experimental condition (4 months plus 2 weeks. Given individual differences in infants' reactivity to social stress events, we categorized infants as increasers or decreasers based on their cortisol reactivity after their initial exposure to the stress of the maternal still-face. Infants in the experimental condition, both increasers and decreasers, showed a significant change in cortisol response after the second exposure to the maternal still-face, though change was different for each reactivity group. In contrast, age-matched infants with no prior exposure to the maternal still-face showed similar post-stress cortisol reactivity to the reactivity of the experimental infants at their first exposure. There were no behavioral differences between increasers and decreasers during the Still-Face paradigm and exposures to the social stress. Thus differences between the experimental and control groups' post-stress cortisol reactivity was associated with the experimental group having previous experience with the social stress. These findings indicate long-term memory for social stress in infants as young as 4 months of age.

  18. A novel whole-cell mechanism for long-term memory enhancement.

    Iris Reuveni

    Full Text Available Olfactory-discrimination learning was shown to induce a profound long-lasting enhancement in the strength of excitatory and inhibitory synapses of pyramidal neurons in the piriform cortex. Notably, such enhancement was mostly pronounced in a sub-group of neurons, entailing about a quarter of the cell population. Here we first show that the prominent enhancement in the subset of cells is due to a process in which all excitatory synapses doubled their strength and that this increase was mediated by a single process in which the AMPA channel conductance was doubled. Moreover, using a neuronal-network model, we show how such a multiplicative whole-cell synaptic strengthening in a sub-group of cells that form a memory pattern, sub-serves a profound selective enhancement of this memory. Network modeling further predicts that synaptic inhibition should be modified by complex learning in a manner that much resembles synaptic excitation. Indeed, in a subset of neurons all GABAA-receptors mediated inhibitory synapses also doubled their strength after learning. Like synaptic excitation, Synaptic inhibition is also enhanced by two-fold increase of the single channel conductance. These findings suggest that crucial learning induces a multiplicative increase in strength of all excitatory and inhibitory synapses in a subset of cells, and that such an increase can serve as a long-term whole-cell mechanism to profoundly enhance an existing Hebbian-type memory. This mechanism does not act as synaptic plasticity mechanism that underlies memory formation but rather enhances the response of already existing memory. This mechanism is cell-specific rather than synapse-specific; it modifies the channel conductance rather than the number of channels and thus has the potential to be readily induced and un-induced by whole-cell transduction mechanisms.

  19. Consolidation of visual associative long-term memory in the temporal cortex of primates.

    Miyashita, Y; Kameyama, M; Hasegawa, I; Fukushima, T

    1998-01-01

    Neuropsychological theories have proposed a critical role for the interaction between the medial temporal lobe and the neocortex in the formation of long-term memory for facts and events, which has often been tested by learning of a series of paired words or figures in humans. We have examined neural mechanisms underlying the memory "consolidation" process by single-unit recording and molecular biological methods in an animal model of a visual pair-association task in monkeys. In our previous studies, we found that long-term associative representations of visual objects are acquired through learning in the neural network of the anterior inferior temporal (IT) cortex. In this article, we propose the hypothesis that limbic neurons undergo rapid modification of synaptic connectivity and provide backward signals that guide the reorganization of neocortical neural circuits. Two experiments tested this hypothesis: (1) we examined the role of the backward connections from the medial temporal lobe to the IT cortex by injecting ibotenic acid into the entorhinal and perirhinal cortices, which provided massive backward projections ipsilaterally to the IT cortex. We found that the limbic lesion disrupted the associative code of the IT neurons between the paired associates, without impairing the visual response to each stimulus. (2) We then tested the first half of this hypothesis by detecting the expression of immediate-early genes in the monkey temporal cortex. We found specific expression of zif268 during the learning of a new set of paired associates in the pair-association task, most intensively in area 36 of the perirhinal cortex. All these results with the visual pair-association task support our hypothesis and demonstrate that the consolidation process, which was first proposed on the basis of clinico-psychological evidence, can now be examined in primates using neurophysiolocical and molecular biological approaches.

  20. Membrane-Associated Glucocorticoid Activity Is Necessary for Modulation of Long-Term Memory via Chromatin Modification

    Roozendaal, Benno; Hernandez, Angelina; Cabrera, Sara M.; Hagewoud, Roelina; Malvaez, Melissa; Stefanko, Daniel P.; Haettig, Jakob; Wood, Marcelo A.

    2010-01-01

    Glucocorticoid hormones enhance the consolidation of long-term memory of emotionally arousing training experiences. This memory enhancement requires activation of the cAMP-dependent kinase pathway and the subsequent phosphorylation of cAMP response-element binding (CREB) protein. Here, we demonstrat

  1. Different Phases of Long-Term Memory Require Distinct Temporal Patterns of PKA Activity after Single-Trial Classical Conditioning

    Michel, Maximilian; Kemenes, Ildiko; Muller, Uli; Kemenes, Gyorgy

    2008-01-01

    The cAMP-dependent protein kinase (PKA) is known to play a critical role in both transcription-independent short-term or intermediate-term memory and transcription-dependent long-term memory (LTM). Although distinct phases of LTM already have been demonstrated in some systems, it is not known whether these phases require distinct temporal patterns…

  2. The compensatory effect of regular exercise on long-term memory impairment in sleep deprived female rats.

    Salari, Maryam; Sheibani, Vahid; Saadati, Hakimeh; Pourrahimi, Alimohammad; khaksarihadad, Mohammad; Esmaeelpour, Khadijeh; Khodamoradi, Mehdi

    2015-10-01

    Previous studies have been shown that exercise can improve short-term spatial learning, memory and synaptic plasticity impairments in sleep deprived female rats. The aim of the present study was to investigate the effects of treadmill exercise on sleep deprivation (SD) induced impairment in hippocampal dependent long-term memory in female rats. Intact and ovariectomized female rats were used in the current study. Exercise protocol was 4 weeks treadmill running. Twenty four hour SD was induced by using multiple platform apparatus after learning phase. Spatial learning and long-term memory was examined by using the Morris Water Maze (MWM) test. Our results indicated that sleep deprivation impaired long term memory in the intact and ovariectomized female rats, regardless of reproductive status (pexercise compensated this impairment (peffect of SD on cognitive functions and regular exercise seems to protect rats from these factors, however more investigations need to be done.

  3. CB2 Cannabinoid Receptor Knockout in Mice Impairs Contextual Long-Term Memory and Enhances Spatial Working Memory

    Yong Li

    2016-01-01

    Full Text Available Neurocognitive effects of cannabinoids have been extensively studied with a focus on CB1 cannabinoid receptors because CB1 receptors have been considered the major cannabinoid receptor in the nervous system. However, recent discoveries of CB2 cannabinoid receptors in the brain demand accurate determination of whether and how CB2 receptors are involved in the cognitive effects of cannabinoids. CB2 cannabinoid receptors are primarily involved in immune functions, but also implicated in psychiatric disorders such as schizophrenia and depression. Here, we examined the effects of CB2 receptor knockout in mice on memory to determine the roles of CB2 receptors in modulating cognitive function. Behavioral assays revealed that hippocampus-dependent, long-term contextual fear memory was impaired whereas hippocampus-independent, cued fear memory was normal in CB2 receptor knockout mice. These mice also displayed enhanced spatial working memory when tested in a Y-maze. Motor activity and anxiety of CB2 receptor knockout mice were intact when assessed in an open field arena and an elevated zero maze. In contrast to the knockout of CB2 receptors, acute blockade of CB2 receptors by AM603 in C57BL/6J mice had no effect on memory, motor activity, or anxiety. Our results suggest that CB2 cannabinoid receptors play diverse roles in regulating memory depending on memory types and/or brain areas.

  4. Enhanced hippocampal long-term potentiation and fear memory in Btbd9 mutant mice.

    Mark P DeAndrade

    Full Text Available Polymorphisms in BTBD9 have recently been associated with higher risk of restless legs syndrome (RLS, a neurological disorder characterized by uncomfortable sensations in the legs at rest that are relieved by movement. The BTBD9 protein contains a BTB/POZ domain and a BACK domain, but its function is unknown. To elucidate its function and potential role in the pathophysiology of RLS, we generated a line of mutant Btbd9 mice derived from a commercial gene-trap embryonic stem cell clone. Btbd9 is the mouse homolog of the human BTBD9. Proteins that contain a BTB/POZ domain have been reported to be associated with synaptic transmission and plasticity. We found that Btbd9 is naturally expressed in the hippocampus of our mutant mice, a region critical for learning and memory. As electrophysiological characteristics of CA3-CA1 synapses of the hippocampus are well characterized, we performed electrophysiological recordings in this region. The mutant mice showed normal input-output relationship, a significant impairment in pre-synaptic activity, and an enhanced long-term potentiation. We further performed an analysis of fear memory and found the mutant mice had an enhanced cued and contextual fear memory. To elucidate a possible molecular basis for these enhancements, we analyzed proteins that have been associated with synaptic plasticity. We found an elevated level of dynamin 1, an enzyme associated with endocytosis, in the mutant mice. These results suggest the first identified function of Btbd9 as being involved in regulating synaptic plasticity and memory. Recent studies have suggested that enhanced synaptic plasticity, analogous to what we have observed, in other regions of the brain could enhance sensory perception similar to what is seen in RLS patients. Further analyses of the mutant mice will help shine light on the function of BTBD9 and its role in RLS.

  5. Post-learning stress enhances long-term memory and differentially influences memory in females depending on menstrual stage.

    Zoladz, Phillip R; Peters, David M; Cadle, Chelsea E; Kalchik, Andrea E; Aufdenkampe, Rachael L; Dailey, Alison M; Brown, Callie M; Scharf, Amanda R; Earley, McKenna B; Knippen, Courtney L; Rorabaugh, Boyd R

    2015-09-01

    Most work has shown that post-learning stress enhances long-term memory; however, there have been recent inconsistencies in this literature. The purpose of the present study was to examine further the effects of post-learning stress on long-term memory and to explore any sex differences that may exist. Male and female participants learned a list of 42 words that varied in emotional valence and arousal level. Following encoding, participants completed a free recall assessment and then submerged their hand into a bath of ice cold (stress) or lukewarm (no stress) water for 3 min. The next day, participants were given free recall and recognition tests. Stressed participants recalled more words than non-stressed participants 24h after learning. Stress also enhanced female participants' recall of arousing words when they were in the follicular, but not luteal, phase. These findings replicate previous work examining post-learning stress effects on memory and implicate the involvement of sex-related hormones in such effects.

  6. The limitations of our knowledge about social influences on memories of sexual abuse over the long-term

    Koppel, Jonathan Mark; Berntsen, Dorthe

    2015-01-01

    Fagin, Cyr, and Hirst provide an informed and insightful application of the social memory literature to the important question of how memories of sexual abuse may be re-shaped, both over the short term and long term, by communication with others, as well as with oneself. In the following commentary......, we outline several respects in which we believe that the application of this literature to memories of sexual abuse, particularly over the long term, is still open to debate. In particular, we focus on induced forgetting and social contagion for such memories, as well as the application of the social...... memory literature to intrusive involuntary memories of trauma. Where applicable, we offer suggestions for future research that may contribute towards addressing the limitations of the existing literature....

  7. Just in time for late-LTP: A mechanism for the role of PKMzeta in long-term memory.

    Vlachos, Andreas; Maggio, Nicola; Jedlicka, Peter

    2008-01-01

    It is a fundamental question in neuroscience how long-term memory formation is regulated at the molecular level. Although widely considered a highly complex process requiring numerous molecular players, it also has been speculated that a single protein could play a pivotal role. This "astonishing hypothesis" has made a significant impact on memory research and has led to a reevaluation of concepts regarding memory formation.1,2.

  8. [Short-and long-term effects of cannabinoids on memory, cognition and mental illness].

    Sagie, Shira; Eliasi, Yehuda; Livneh, Ido; Bart, Yosi; Monovich, Einat

    2013-12-01

    Marijuana is considered the most commonly used drug in the world, with estimated millions of users. There is dissent in the medical world about the positive and negative effects of marijuana, and recently, a large research effort has been directed to that domain. The main influencing drug ingredient is THC, which acts on the cannabinoid system and binds to the CB1 receptor. The discovery of the receptor led to the finding of an endogenous ligand, anandamide, and another receptor-CB2. The researchers also discovered that cannabinoids have extensive biological activity, and its short and long-term effects may cause cognitive and emotional deficiencies. Findings show that the short-term effects, such as shortterm memory and verbal Learning, are reversible. However, despite the accumulation of evidence about long-term cognitive damage due to cannabis use, it is difficult to find unequivocal results, arising from the existence of many variables such as large differences between cannabis users, frequency of use, dosage and endogenous brain compensation. Apart from cognitive damage, current studies investigate how marijuana affects mental illness: a high correlation between cannabis use and schizophrenia was found and a high risk to undergo a psychotic attack. Furthermore, patients with schizophrenia who used cannabis showed a selective neuro-psychological disruption, and similar cognitive deficiencies and brain morphological changes were found among healthy cannabis users and schizophrenia patients. In contrast to the negative effects of marijuana including addiction, there are the medical uses: reducing pain, anxiety and nausea, increasing appetite and an anti-inflammatory activity. Medicalization of marijuana encourages frequent use, which may elevate depression.

  9. Expertise in cognitive psychology: testing the hypothesis of long-term working memory in a study of soccer players.

    Postal, Virginie

    2004-10-01

    This experiment compared several theories of expertise and exceptional performances in cognitive psychology. One current conception assumes that experts in a specific domain have developed a long-term working memory, which accounts for the difference in memory performance between experts and novices. The principal characteristics of this memory are the speed with which processes of storage and retrieval function and the existence of retrieval structures that allow a temporary activation of the knowledge store in long-term memory. Other authors such as Vicente and Wang argue this notion does not account for memory performance that is not intrinsic to the domain of expertise. We attempt to clarify the two viewpoints and to focus on this debate by testing the hypothesis of long-term working memory using soccer as the domain of expertise and by comparing the cognitive performance of participants who have different expertise (novices, supporters, players, and coaches). 35 male participants were administered a new version of the Reading Span test to assess their long-term working memory according to two conditions. In the first condition (structured condition), the last word of each sentence was related to the soccer domain, and these words were related to each other in such a manner that they represented a part of the game. In the second condition (unstructured condition), the last word of each sentence was related to soccer but these words did not represent part of the game. Analysis showed that the sentence span increased as a function of expertise for the structured condition but not for the unstructured condition. The results were interpreted in the framework of the constraint attunement hypothesis proposed by Vicente in 1992 and the long-term working memory hypothesis proposed by Ericsson and Kintsch in 1995.

  10. Rapamycin restores BDNF-LTP and the persistence of long-term memory in a model of Down's syndrome.

    Andrade-Talavera, Yuniesky; Benito, Itziar; Casañas, Juan José; Rodríguez-Moreno, Antonio; Montesinos, María Luz

    2015-10-01

    Down's syndrome (DS) is the most prevalent genetic intellectual disability. Memory deficits significantly contribute to the cognitive dysfunction in DS. Previously, we discovered that mTOR-dependent local translation, a pivotal process for some forms of synaptic plasticity, is deregulated in a DS mouse model. Here, we report that these mice exhibit deficits in both synaptic plasticity (i.e., BDNF-long term potentiation) and the persistence of spatial long-term memory. Interestingly, these deficits were fully reversible using rapamycin, a Food and Drug Administration-approved specific mTOR inhibitor; therefore, rapamycin may be a novel pharmacotherapy to improve cognition in DS.

  11. Long-term heavy ketamine use is associated with spatial memory impairment and altered hippocampal activation

    Celia J A Morgan

    2014-12-01

    Full Text Available Ketamine, a non-competitive N-methyl-D-aspartate receptor antagonist, is rising in popularity as a drug of abuse. Preliminary evidence suggests that chronic, heavy ketamine use may have profound effects on spatial memory but the mechanism of these deficits is as yet unclear. This study aimed to examine the neural mechanism by which heavy ketamine use impairs spatial memory processing. In a sample of 11 frequent ketamine users and 15 polydrug controls, matched for IQ, age and years in education. We used fMRI utilising an ROI approach to examine the neural activity of three regions known to support successful navigation; the hippocampus, parahippocampal gyrus and the caudate nucleus during a virtual reality task of spatial memory. Frequent ketamine users displayed spatial memory deficits, accompanied by and related to, reduced activation in both the right hippocampus and left parahippocampal gyrus during navigation from memory, and in the left caudate during memory updating, compared to controls. Ketamine users also exhibited schizotypal and dissociative symptoms that were related to hippocampal activation. Impairments in spatial memory observed in ketamine users are related to changes in medial temporal lobe activation. Disrupted medial temporal lobe function may be a consequence of chronic ketamine abuse and may relate to schizophrenia-like symptomatology observed in ketamine users.

  12. What does the brain do while playing scrabble?: ERPs associated with a short-long-term memory task.

    Cansino, S; Ruiz, A; López-Alonso, V

    1999-03-01

    Event-related brain potentials (ERPs) were recorded while subjects performed the scrabble paradigm, a cued recall task that demands retrieving semantic memory information from long-term memory since subjects are not exposed to a previous study phase. The task combines short- and long-term memory processes and consists of forming words from a set of letters presented in random order. Short-term memory was manipulated by varying the number of letters (three, four and five) presented to the subject, while semantic memory was examined by comparing correct trials with no response trials. Behavioral results reveal that the subjects performed the task serially, as denoted by a linear reaction time increment as the number of random letters in the set increased. Short-term memory procedures were reflected by an amplitude increase of the N200 and by an amplitude decrease of the P300 increasing the number of letters. Successfully retrieving semantic information from long-term memory was indexed by a negative slow wave recorded at left frontal and left central sites, and by a positive slow wave predominant over right hemisphere sites. These findings provide evidence that semantic retrieval memory involves activity from both left and right hemispheres.

  13. Divergent short- and long-term effects of acute stress in object recognition memory are mediated by endogenous opioid system activation.

    Nava-Mesa, Mauricio O; Lamprea, Marisol R; Múnera, Alejandro

    2013-11-01

    Acute stress induces short-term object recognition memory impairment and elicits endogenous opioid system activation. The aim of this study was thus to evaluate whether opiate system activation mediates the acute stress-induced object recognition memory changes. Adult male Wistar rats were trained in an object recognition task designed to test both short- and long-term memory. Subjects were randomly assigned to receive an intraperitoneal injection of saline, 1 mg/kg naltrexone or 3 mg/kg naltrexone, four and a half hours before the sample trial. Five minutes after the injection, half the subjects were submitted to movement restraint during four hours while the other half remained in their home cages. Non-stressed subjects receiving saline (control) performed adequately during the short-term memory test, while stressed subjects receiving saline displayed impaired performance. Naltrexone prevented such deleterious effect, in spite of the fact that it had no intrinsic effect on short-term object recognition memory. Stressed subjects receiving saline and non-stressed subjects receiving naltrexone performed adequately during the long-term memory test; however, control subjects as well as stressed subjects receiving a high dose of naltrexone performed poorly. Control subjects' dissociated performance during both memory tests suggests that the short-term memory test induced a retroactive interference effect mediated through light opioid system activation; such effect was prevented either by low dose naltrexone administration or by strongly activating the opioid system through acute stress. Both short-term memory retrieval impairment and long-term memory improvement observed in stressed subjects may have been mediated through strong opioid system activation, since they were prevented by high dose naltrexone administration. Therefore, the activation of the opioid system plays a dual modulating role in object recognition memory.

  14. Differential role of entorhinal and hippocampal nerve growth factor in short- and long-term memory modulation

    Walz R.

    2005-01-01

    Full Text Available We studied the effects of infusion of nerve growth factor (NGF into the hippocampus and entorhinal cortex of male Wistar rats (250-300 g, N = 11-13 per group on inhibitory avoidance retention. In order to evaluate the modulation of entorhinal and hippocampal NGF in short- and long-term memory, animals were implanted with cannulae in the CA1 area of the dorsal hippocampus or entorhinal cortex and trained in one-trial step-down inhibitory avoidance (foot shock, 0.4 mA. Retention tests were carried out 1.5 h or 24 h after training to measure short- and long-term memory, respectively. Immediately after training, rats received 5 µl NGF (0.05, 0.5 or 5.0 ng or saline per side into the CA1 area and entorhinal cortex. The correct position of the cannulae was confirmed by histological analysis. The highest dose of NGF (5.0 ng into the hippocampus blocked short-term memory (P < 0.05, whereas the doses of 0.5 (P < 0.05 and 5.0 ng (P < 0.01 NGF enhanced long-term memory. NGF administration into the entorhinal cortex improved long-term memory at the dose of 5.0 ng (P < 0.05 and did not alter short-term memory. Taken as a whole, our results suggest a differential modulation by entorhinal and hippocampal NGF of short- and long-term memory.

  15. CNTRICS imaging biomarkers final task selection: Long-term memory and reinforcement learning.

    Ragland, John D; Cohen, Neal J; Cools, Roshan; Frank, Michael J; Hannula, Deborah E; Ranganath, Charan

    2012-01-01

    Functional imaging paradigms hold great promise as biomarkers for schizophrenia research as they can detect altered neural activity associated with the cognitive and emotional processing deficits that are so disabling to this patient population. In an attempt to identify the most promising functional imaging biomarkers for research on long-term memory (LTM), the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) initiative selected "item encoding and retrieval," "relational encoding and retrieval," and "reinforcement learning" as key LTM constructs to guide the nomination process. This manuscript reports on the outcome of the third CNTRICS biomarkers meeting in which nominated paradigms in each of these domains were discussed by a review panel to arrive at a consensus on which of the nominated paradigms could be recommended for immediate translational development. After briefly describing this decision process, information is presented from the nominating authors describing the 4 functional imaging paradigms that were selected for immediate development. In addition to describing the tasks, information is provided on cognitive and neural construct validity, sensitivity to behavioral or pharmacological manipulations, availability of animal models, psychometric characteristics, effects of schizophrenia, and avenues for future development.

  16. Neural mechanisms underlying the impact of visual distraction on retrieval of long-term memory.

    Wais, Peter E; Rubens, Michael T; Boccanfuso, Jacqueline; Gazzaley, Adam

    2010-06-23

    Filtering information on the basis of what is relevant to accomplish our goals is a critical process supporting optimal cognitive performance. However, it is not known whether exposure to irrelevant environmental stimuli impairs our ability to accurately retrieve long-term memories. We hypothesized that visual processing of irrelevant visual information would interfere with mental visualization engaged during recall of the details of a prior experience, despite goals to direct full attention to the retrieval task. In the current study, we compared performance on a cued-recall test of previously studied visual items when participants' eyes were closed to performance when their eyes were open and irrelevant visual stimuli were presented. A behavioral experiment revealed that recollection of episodic details was diminished in the presence of the irrelevant information. A functional magnetic resonance imaging experiment using the same paradigm replicated the behavioral results and found that diminished recollection was associated with the disruption of functional connectivity in a network involving the left inferior frontal gyrus, hippocampus and visual association cortex. Network connectivity supported recollection of contextual details based on visual imagery when eyes were closed, but declined in the presence of irrelevant visual information. We conclude that bottom-up influences from irrelevant visual information interfere with top-down selection of episodic details mediated by a capacity-limited frontal control region, resulting in impaired recollection.

  17. Multiple interpretations of long-term working memory theory: Reply to Delaney and Ericsson (2016).

    Foroughi, Cyrus K; Werner, Nicole E; Barragán, Daniela; Boehm-Davis, Deborah A

    2016-10-01

    This reply is in response to Delaney and Ericsson (2016), who argue that the results of our recent research (Foroughi, Werner, Barragán, & Boehm-Davis, 2015) can be explained by Ericsson and Kintsch's (1995) long-term working memory (LTWM) theory. Our original work was designed to test the prediction made by LTWM theory that interruptions of up to 30 s in duration would not disrupt reading performance. We conducted the work following the method and outcome measures recommended by Ericsson and Kintsch (1995). Our data were clear: interruptions disrupted reading comprehension. We believe that these data do not support predictions made by LTWM theory. Although we appreciate Delaney and Ericsson's (2016) comments, we are unsure how best to move forward because it appears that some of their comments are not consistent with the published work on LTWM theory. Because of the inconsistent and contradictory claims surrounding LTWM theory, the theory does not appear to be falsifiable, or is in danger of becoming unfalsifiable. Creating and testing theory is vital for the advancement of psychological science, but it appears that testing predictions made by LTWM would be very difficult, if not impossible, given the fluid state of the theory. (PsycINFO Database Record

  18. Effects of long-term electromagnetic field exposure on spatial learning and memory in rats.

    Hao, Dongmei; Yang, Lei; Chen, Su; Tong, Jun; Tian, Yonghao; Su, Benhang; Wu, Shuicai; Zeng, Yanjun

    2013-02-01

    With the development of communications industry, mobile phone plays an important role in daily life. Whether or not the electromagnetic radiation emitted by mobile phone causes any adverse effects on brain function has become of a great concern. This paper investigated the effect of electromagnetic field on spatial learning and memory in rats. 32 trained Wistar rats were divided into two groups: exposure group and control group. The exposure group was exposed to 916 MHz, 10w/m2 mobile phone electromagnetic field (EMF) 6 h a day, 5 days a week, 10 weeks. The completion time, number of total errors and the neuron discharge signals were recorded while the rats were searching for food in an eight-arm radial maze at every weekend. The neuron signals of one exposed rat and one control rat in the maze were obtained by the implanted microelectrode arrays in their hippocampal regions. It can be seen that during the weeks 4-5 of the experiment, the average completion time and error rate of the exposure group were longer and larger than that of control group (p exposure, and the rats can adapt to long-term EMF exposure.

  19. Genome-wide functional analysis of CREB/long-term memory-dependent transcription reveals distinct basal and memory gene expression programs.

    Lakhina, Vanisha; Arey, Rachel N; Kaletsky, Rachel; Kauffman, Amanda; Stein, Geneva; Keyes, William; Xu, Daniel; Murphy, Coleen T

    2015-01-21

    Induced CREB activity is a hallmark of long-term memory, but the full repertoire of CREB transcriptional targets required specifically for memory is not known in any system. To obtain a more complete picture of the mechanisms involved in memory, we combined memory training with genome-wide transcriptional analysis of C. elegans CREB mutants. This approach identified 757 significant CREB/memory-induced targets and confirmed the involvement of known memory genes from other organisms, but also suggested new mechanisms and novel components that may be conserved through mammals. CREB mediates distinct basal and memory transcriptional programs at least partially through spatial restriction of CREB activity: basal targets are regulated primarily in nonneuronal tissues, while memory targets are enriched for neuronal expression, emanating from CREB activity in AIM neurons. This suite of novel memory-associated genes will provide a platform for the discovery of orthologous mammalian long-term memory components.

  20. Long-Term Memory: A Review and Meta-Analysis of Studies of Declarative and Procedural Memory in Specific Language Impairment

    Lum, Jarrad A. G.; Conti-Ramsden, Gina

    2013-01-01

    This review examined the status of long-term memory systems in specific language impairment (SLI)--declarative memory and aspects of procedural memory in particular. Studies included in the review were identified following a systematic search of the literature and findings combined using meta-analysis. This review showed that individuals with SLI…

  1. On the simple random-walk models of ion-channel gate dynamics reflecting long-term memory.

    Wawrzkiewicz, Agata; Pawelek, Krzysztof; Borys, Przemyslaw; Dworakowska, Beata; Grzywna, Zbigniew J

    2012-06-01

    Several approaches to ion-channel gating modelling have been proposed. Although many models describe the dwell-time distributions correctly, they are incapable of predicting and explaining the long-term correlations between the lengths of adjacent openings and closings of a channel. In this paper we propose two simple random-walk models of the gating dynamics of voltage and Ca(2+)-activated potassium channels which qualitatively reproduce the dwell-time distributions, and describe the experimentally observed long-term memory quite well. Biological interpretation of both models is presented. In particular, the origin of the correlations is associated with fluctuations of channel mass density. The long-term memory effect, as measured by Hurst R/S analysis of experimental single-channel patch-clamp recordings, is close to the behaviour predicted by our models. The flexibility of the models enables their use as templates for other types of ion channel.

  2. When music and long-term memory interact: effects of musical expertise on functional and structural plasticity in the hippocampus.

    Groussard, Mathilde; La Joie, Renaud; Rauchs, Géraldine; Landeau, Brigitte; Chételat, Gaël; Viader, Fausto; Desgranges, Béatrice; Eustache, Francis; Platel, Hervé

    2010-10-05

    The development of musical skills by musicians results in specific structural and functional modifications in the brain. Surprisingly, no functional magnetic resonance imaging (fMRI) study has investigated the impact of musical training on brain function during long-term memory retrieval, a faculty particularly important in music. Thus, using fMRI, we examined for the first time this process during a musical familiarity task (i.e., semantic memory for music). Musical expertise induced supplementary activations in the hippocampus, medial frontal gyrus, and superior temporal areas on both sides, suggesting a constant interaction between episodic and semantic memory during this task in musicians. In addition, a voxel-based morphometry (VBM) investigation was performed within these areas and revealed that gray matter density of the hippocampus was higher in musicians than in nonmusicians. Our data indicate that musical expertise critically modifies long-term memory processes and induces structural and functional plasticity in the hippocampus.

  3. When music and long-term memory interact: effects of musical expertise on functional and structural plasticity in the hippocampus.

    Mathilde Groussard

    Full Text Available The development of musical skills by musicians results in specific structural and functional modifications in the brain. Surprisingly, no functional magnetic resonance imaging (fMRI study has investigated the impact of musical training on brain function during long-term memory retrieval, a faculty particularly important in music. Thus, using fMRI, we examined for the first time this process during a musical familiarity task (i.e., semantic memory for music. Musical expertise induced supplementary activations in the hippocampus, medial frontal gyrus, and superior temporal areas on both sides, suggesting a constant interaction between episodic and semantic memory during this task in musicians. In addition, a voxel-based morphometry (VBM investigation was performed within these areas and revealed that gray matter density of the hippocampus was higher in musicians than in nonmusicians. Our data indicate that musical expertise critically modifies long-term memory processes and induces structural and functional plasticity in the hippocampus.

  4. Long-Term Memory for the Terrorist Attack of September 11: Flashbulb Memories, Event Memories, and the Factors that Influence Their Retention

    Hirst, William; Phelps, Elizabeth A.; Buckner, Randy L.; Budson, Andrew E.; Cuc, Alexandru; Gabrieli, John D. E.; Johnson, Marcia K.; Lustig, Cindy; Lyle, Keith B.; Mather, Mara; Meksin, Robert; Mitchell, Karen J.; Ochsner, Kevin N.; Schacter, Daniel L.; Simons, Jon S.; Vaidya, Chandan J.

    2009-01-01

    More than 3,000 individuals from 7 U.S. cities reported on their memories of learning of the terrorist attacks of September 11, as well as details about the attack, 1 week, 11 months, and/or 35 months after the assault. Some studies of flashbulb memories examining long-term retention show slowing in the rate of forgetting after a year, whereas…

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

    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…

  6. Fan-Shaped Body Neurons Are Involved in "Period"-Dependent Regulation of Long-Term Courtship Memory in "Drosophila"

    Sakai, Takaomi; Inami, Show; Sato, Shoma; Kitamoto, Toshihiro

    2012-01-01

    In addition to its established function in the regulation of circadian rhythms, the "Drosophila" gene "period" ("per") also plays an important role in processing long-term memory (LTM). Here, we used courtship conditioning as a learning paradigm and revealed that (1) overexpression and knocking down of "per" in subsets of brain neurons enhance and…

  7. Transitions between Short-Term and Long-Term Memory in Learning Meaningful Unrelated Paired Associates Using Computer Based Drills.

    Goldenberg, Tzvika Y.; Turnure, James E.

    1989-01-01

    Discussion of short-term and long-term memory in learning paired associates focuses on two microcomputer-based instructional design experiments with eleventh and twelfth graders that were modeled after traditional drill and practice routines. Research questions are presented, treatment conditions are explained, and additional research is…

  8. PV plasticity sustained through D1/5 dopamine signaling required for long-term memory consolidation.

    Karunakaran, Smitha; Chowdhury, Ananya; Donato, Flavio; Quairiaux, Charles; Michel, Christoph M; Caroni, Pico

    2016-03-01

    Long-term consolidation of memories depends on processes occurring many hours after acquisition. Whether this involves plasticity that is specifically required for long-term consolidation remains unclear. We found that learning-induced plasticity of local parvalbumin (PV) basket cells was specifically required for long-term, but not short/intermediate-term, memory consolidation in mice. PV plasticity, which involves changes in PV and GAD67 expression and connectivity onto PV neurons, was regulated by cAMP signaling in PV neurons. Following induction, PV plasticity depended on local D1/5 dopamine receptor signaling at 0-5 h to regulate its magnitude, and at 12-14 h for its continuance, ensuring memory consolidation. D1/5 dopamine receptor activation selectively induced DARPP-32 and ERK phosphorylation in PV neurons. At 12-14 h, PV plasticity was required for enhanced sharp-wave ripple densities and c-Fos expression in pyramidal neurons. Our results reveal general network mechanisms of long-term memory consolidation that requires plasticity of PV basket cells induced after acquisition and sustained subsequently through D1/5 receptor signaling.

  9. PKA and PKC Are Required for Long-Term but Not Short-Term in Vivo Operant Memory in "Aplysia"

    Michel, Maximilian; Green, Charity L.; Lyons, Lisa C.

    2011-01-01

    We investigated the involvement of PKA and PKC signaling in a negatively reinforced operant learning paradigm in "Aplysia", learning that food is inedible (LFI). In vivo injection of PKA or PKC inhibitors blocked long-term LFI memory formation. Moreover, a persistent phase of PKA activity, although not PKC activity, was necessary for long-term…

  10. The effects of cortisol increase on long-term memory retrieval during and after acute psychosocial stress

    Tollenaar, M.S.; Elzinga, B.M.; Spinhoven, P.; Everaerd, W.A.M.

    2008-01-01

    In this study the effects of stress-induced cortisol increases on long-term memory retrieval during and after acute psychosocial stress were examined. Seventy male students were exposed to either a psychosocial stress task or to a non-stressful control task. During and after this task, retrieval was

  11. Long-term effects of frequent cannabis use on working memory and attention : an fMRI study

    Jager, G; Kahn, RS; Van den Brink, W; Van Ree, JM; Ramsey, NF

    2006-01-01

    Rationale: Excessive use of cannabis may have long-term effects on cognitive abilities. Mild impairments have been found in several cognitive domains, particularly in memory and attention. It is not clear, however, whether these effects also occur with moderate, recreational use of cannabis. Further

  12. The Calmodulin-Binding Transcription Activator CAMTA1 Is Required for Long-Term Memory Formation in Mice

    Bas-Orth, Carlos; Tan, Yan-Wei; Oliveira, Ana M. M.; Bengtson, C. Peter; Bading, Hilmar

    2016-01-01

    The formation of long-term memory requires signaling from the synapse to the nucleus to mediate neuronal activity-dependent gene transcription. Synapse-to-nucleus communication is initiated by influx of calcium ions through synaptic NMDA receptors and/or L-type voltage-gated calcium channels and involves the activation of transcription factors by…

  13. Spacing Effect: SHP2 Phosphatase Regulates Resting Intervals Between Learning Trials in Long-Term Memory Induction

    Pagani, Mario R.; Oishi, Kimihiko; Gelb, Bruce D.; Zhong, Yi

    2009-01-01

    A common property of long-term memory (LTM) induction is the requirement for repeated training sessions spaced over time. The phenomena of better memory being formed with resting intervals between training sessions is called the spacing effect, for which the underlying molecular and neural bases are largely unknown. Our study reveals that the duration of resting intervals required for inducing LTM can be regulated by activity levels of the protein tyrosine phosphatase corkscrew (CSW) in Droso...

  14. On the interplay between short and long term memory in the power-law cross-correlations setting

    Kristoufek, Ladislav

    2014-01-01

    We focus on emergence of the power-law cross-correlations from processes with both short and long term memory properties. In the case of correlated error-terms, the power-law decay of the cross-correlation function comes automatically with the characteristics of the separate processes. The bivariate Hurst exponent is then equal to an average of the separate Hurst exponents of the analysed processes. Strength of the short term memory has no effect on these asymptotic properties.

  15. Hippocampal CA1 Kindling but Not Long-Term Potentiation Disrupts Spatial Memory Performance

    Leung, L. Stan; Shen, Bixia

    2006-01-01

    Long-term synaptic enhancement in the hippocampus has been suggested to cause deficits in spatial performance. Synaptic enhancement has been reported after hippocampal kindling that induced repeated electrographic seizures or afterdischarges (ADs) and after long-term potentiation (LTP) defined as synaptic enhancement without ADs. We studied…

  16. Long-term storage of samples for flow cytometric DNA analysis

    Vindeløv, L L; Christensen, I J; Keiding, N

    1983-01-01

    A simple procedure for long-term storage of cells for flow cytometric DNA analysis was developed and tested. The cells were stored as single cells or fine-needle aspirates suspended in a citrate buffer with dimethylsulfoxide (DMSO), or as small blocks of tissue from solid tumors. The cells were...... stored for up to one year by freezing at -80 degrees C. Statistical analysis of the results showed no change in the fractions of cells in the cell cycle phases as determined by deconvolution of the DNA-histograms. It was found that in addition to the intrinsic sample variation from the parameter...... of the analysis. The storage method makes sample collection independent of immediate subsequent analysis. This has enabled us to perform large internally controlled experiments, involving more samples than can be analyzed in one day, to examine tumor samples from different hospitals and to utilize fully...

  17. Long-term memory for the terrorist attack of September 11: Flashbulb memories, event memories, and the factors that influence their retention

    Hirst, William; Phelps, Elizabeth A.; Buckner, Randy L.; Budson, Andrew E.; Cuc, Alexandru; Gabrieli, John D. E.; Johnson, Marcia K.; Lyle, Keith B.; Lustig, Cindy; Mather, Mara; Meksin, Robert; Mitchell, Karen J.; Ochsner, Kevin N.; Schacter, Daniel L.; Simons, Jon S.; Vaidya, Chandan J.

    2010-01-01

    More than 3,000 individuals from seven US cities reported on their memories of learning of the terrorist attacks of September 11, as well as details about the attack, one week, 11 months, and/or 35 months after the assault. Some studies of flashbulb memories examining long-term retention show slowing in the rate of forgetting after a year, whereas others demonstrate accelerated forgetting. The present paper indicates that (1) the rate of forgetting for flashbulb memories and event memory (memory for details about the event itself) slows after a year, (2) the strong emotional reactions elicited by flashbulb events are remembered poorly, worse than non-emotional features such as where and from whom one learned of the attack, and (3) the content of flashbulb and event memories stabilizes after a year. The results are discussed in terms of community memory practices. PMID:19397377

  18. Tc1 mouse model of trisomy-21 dissociates properties of short- and long-term recognition memory.

    Hall, Jessica H; Wiseman, Frances K; Fisher, Elizabeth M C; Tybulewicz, Victor L J; Harwood, John L; Good, Mark A

    2016-04-01

    The present study examined memory function in Tc1 mice, a transchromosomic model of Down syndrome (DS). Tc1 mice demonstrated an unusual delay-dependent deficit in recognition memory. More specifically, Tc1 mice showed intact immediate (30sec), impaired short-term (10-min) and intact long-term (24-h) memory for objects. A similar pattern was observed for olfactory stimuli, confirming the generality of the pattern across sensory modalities. The specificity of the behavioural deficits in Tc1 mice was confirmed using APP overexpressing mice that showed the opposite pattern of object memory deficits. In contrast to object memory, Tc1 mice showed no deficit in either immediate or long-term memory for object-in-place information. Similarly, Tc1 mice showed no deficit in short-term memory for object-location information. The latter result indicates that Tc1 mice were able to detect and react to spatial novelty at the same delay interval that was sensitive to an object novelty recognition impairment. These results demonstrate (1) that novelty detection per se and (2) the encoding of visuo-spatial information was not disrupted in adult Tc1 mice. The authors conclude that the task specific nature of the short-term recognition memory deficit suggests that the trisomy of genes on human chromosome 21 in Tc1 mice impacts on (perirhinal) cortical systems supporting short-term object and olfactory recognition memory.

  19. Two Pairs of Mushroom Body Efferent Neurons Are Required for Appetitive Long-Term Memory Retrieval in Drosophila

    Pierre-Yves Plaçais

    2013-11-01

    Full Text Available One of the challenges facing memory research is to combine network- and cellular-level descriptions of memory encoding. In this context, Drosophila offers the opportunity to decipher, down to single-cell resolution, memory-relevant circuits in connection with the mushroom bodies (MBs, prominent structures for olfactory learning and memory. Although the MB-afferent circuits involved in appetitive learning were recently described, the circuits underlying appetitive memory retrieval remain unknown. We identified two pairs of cholinergic neurons efferent from the MB α vertical lobes, named MB-V3, that are necessary for the retrieval of appetitive long-term memory (LTM. Furthermore, LTM retrieval was correlated to an enhanced response to the rewarded odor in these neurons. Strikingly, though, silencing the MB-V3 neurons did not affect short-term memory (STM retrieval. This finding supports a scheme of parallel appetitive STM and LTM processing.

  20. Do serotonin(1-7) receptors modulate short and long-term memory?

    Meneses, A

    2007-05-01

    Evidence from invertebrates to human studies indicates that serotonin (5-hydroxytryptamine; 5-HT) system modulates short- (STM) and long-term memory (LTM). This work is primarily focused on analyzing the contribution of 5-HT, cholinergic and glutamatergic receptors as well as protein synthesis to STM and LTM of an autoshaping learning task. It was observed that the inhibition of hippocampal protein synthesis or new mRNA did not produce a significant effect on autoshaping STM performance but it did impair LTM. Both non-contingent protein inhibition and 5-HT depletion showed no effects. It was basically the non-selective 5-HT receptor antagonist cyproheptadine, which facilitated STM. However, the blockade of glutamatergic and cholinergic transmission impaired STM. In contrast, the selective 5-HT(1B) receptor antagonist SB-224289 facilitated both STM and LTM. Selective receptor antagonists for the 5-HT(1A) (WAY100635), 5-HT(1D) (GR127935), 5-HT(2A) (MDL100907), 5-HT(2C/2B) (SB-200646), 5-HT(3) (ondansetron) or 5-HT(4) (GR125487), 5-HT(6) (Ro 04-6790, SB-399885 and SB-35713) or 5-HT(7) (SB-269970) did not impact STM. Nevertheless, WAY100635, MDL100907, SB-200646, GR125487, Ro 04-6790, SB-399885 or SB-357134 facilitated LTM. Notably, some of these changes shown to be independent of food-intake. Concomitantly, these data indicate that '5-HT tone via 5-HT(1B) receptors' might function in a serial manner from STM to LTM, whereas working in parallel using 5-HT(1A), 5-HT(2A), 5-HT(2B/2C), 5-HT(4), or 5-HT(6) receptors.

  1. Failure of delayed nonsynaptic neuronal plasticity underlies age-associated long-term associative memory impairment

    Watson Shawn N

    2012-08-01

    Full Text Available Abstract Background Cognitive impairment associated with subtle changes in neuron and neuronal network function rather than widespread neuron death is a feature of the normal aging process in humans and animals. Despite its broad evolutionary conservation, the etiology of this aging process is not well understood. However, recent evidence suggests the existence of a link between oxidative stress in the form of progressive membrane lipid peroxidation, declining neuronal electrical excitability and functional decline of the normal aging brain. The current study applies a combination of behavioural and electrophysiological techniques and pharmacological interventions to explore this hypothesis in a gastropod model (Lymnaea stagnalis feeding system that allows pinpointing the molecular and neurobiological foundations of age-associated long-term memory (LTM failure at the level of individual identified neurons and synapses. Results Classical appetitive reward-conditioning induced robust LTM in mature animals in the first quartile of their lifespan but failed to do so in animals in the last quartile of their lifespan. LTM failure correlated with reduced electrical excitability of two identified serotonergic modulatory interneurons (CGCs critical in chemosensory integration by the neural network controlling feeding behaviour. Moreover, while behavioural conditioning induced delayed-onset persistent depolarization of the CGCs known to underlie appetitive LTM formation in this model in the younger animals, it failed to do so in LTM-deficient senescent animals. Dietary supplementation of the lipophilic anti-oxidant α-tocopherol reversed the effect of age on CGCs electrophysiological characteristics but failed to restore appetitive LTM function. Treatment with the SSRI fluoxetine reversed both the neurophysiological and behavioural effects of age in senior animals. Conclusions The results identify the CGCs as cellular loci of age-associated appetitive

  2. Differences in the verbal fluency, working memory and executive functions in alcoholics: Short-term vs. long-term abstainers.

    Nowakowska-Domagała, Katarzyna; Jabłkowska-Górecka, Karolina; Mokros, Łukasz; Koprowicz, Jacek; Pietras, Tadeusz

    2017-03-01

    The aim of the study was to assess differences in verbal fluency, working memory and executive functions in two subgroups of alcohol-dependent patients, those undergoing short-term abstinence (STA) and those undergoing long-term abstinence (LTA), and to compare the level of cognitive functions in patients after long-term abstinence with healthy subjects. The study group consisted of 106 alcohol-dependent patients (53 immediately after drinking at least 3 days and 53 after at least one-year abstinence). The control group comprised 53 subjects, whose age, sex and education levels matched those of the patients in the experimental group. The dependence intensity was assessed using SADD and MAST scales. The neuropsychological assessment was based on the FAS Test, Stroop Test and TMT A&B Test. The results obtained for alcohol-dependent patients revealed significant disturbances of cognitive functions. Such results indicate the presence of severe frontal cerebral cortex dysfunctions. Frontal cortex dysfunctions affecting the verbal fluency and working memory subsystems and the executive functions also persisted during long-term abstinence periods. No significant correlations between the duration of dependence, quantity of alcohol consumed and efficiency of the working memory and executive functions were observed in alcohol-dependent subjects after short-term or long-term abstinence.

  3. The roles of long-term phonotactic and lexical prosodic knowledge in phonological short-term memory.

    Tanida, Yuki; Ueno, Taiji; Lambon Ralph, Matthew A; Saito, Satoru

    2015-04-01

    Many previous studies have explored and confirmed the influence of long-term phonological representations on phonological short-term memory. In most investigations, phonological effects have been explored with respect to phonotactic constraints or frequency. If interaction between long-term memory and phonological short-term memory is a generalized principle, then other phonological characteristics-that is, suprasegmental aspects of phonology-should also exert similar effects on phonological short-term memory. We explored this hypothesis through three immediate serial-recall experiments that manipulated Japanese nonwords with respect to lexical prosody (pitch-accent type, reflecting suprasegmental characteristics) as well as phonotactic frequency (reflecting segmental characteristics). The results showed that phonotactic frequency affected the retention not only of the phonemic sequences, but also of pitch-accent patterns, when participants were instructed to recall both the phoneme sequence and accent pattern of nonwords. In addition, accent pattern typicality influenced the retention of the accent pattern: Typical accent patterns were recalled more accurately than atypical ones. These results indicate that both long-term phonotactic and lexical prosodic knowledge contribute to phonological short-term memory performance.

  4. Hyperfunction of muscarinic receptor maintains long-term memory in 5-HT4 receptor knock-out mice.

    Luis Segu

    Full Text Available Patients suffering from dementia of Alzheimer's type express less serotonin 4 receptors (5-HTR(4, but whether an absence of these receptors modifies learning and memory is unexplored. In the spatial version of the Morris water maze, we show that 5-HTR(4 knock-out (KO and wild-type (WT mice performed similarly for spatial learning, short- and long-term retention. Since 5-HTR(4 control mnesic abilities, we tested whether cholinergic system had circumvented the absence of 5-HTR(4. Inactivating muscarinic receptor with scopolamine, at an ineffective dose (0.8 mg/kg to alter memory in WT mice, decreased long-term but not short-term memory of 5-HTR(4 KO mice. Other changes included decreases in the activity of choline acetyltransferase (ChAT, the required enzyme for acetylcholine synthesis, in the septum and the dorsal hippocampus in 5-HTR(4 KO under baseline conditions. Training- and scopolamine-induced increase and decrease, respectively in ChAT activity in the septum in WT mice were not detected in the 5-HTR(4 KO animals. Findings suggest that adaptive changes in cholinergic systems may circumvent the absence of 5-HTR(4 to maintain long-term memory under baseline conditions. In contrast, despite adaptive mechanisms, the absence of 5-HTR(4 aggravates scopolamine-induced memory impairments. The mechanisms whereby 5-HTR(4 mediate a tonic influence on ChAT activity and muscarinic receptors remain to be determined.

  5. Docosahexaenoic Acid Rescues Synaptogenesis Impairment and Long-Term Memory Deficits Caused by Postnatal Multiple Sevoflurane Exposures

    Guorong Tao

    2016-01-01

    Full Text Available Sevoflurane exposures were demonstrated to induce neurotoxicity in the developing brain in both human and animal studies. However, there is no effective approach to reverse it. The present study aimed to evaluate the feasibility of utilizing docosahexaenoic acid (DHA to prevent sevoflurane-induced neurotoxicity. P6 (postnatal 6 days mice were administrated DHA after exposure to 3% sevoflurane for two hours daily in three consecutive days. Molecular expressions of synaptic makers (PSD95, synaptophysin and synaptic morphological changes were investigated by Western blot analysis and transmission electron microscopy, respectively. Meanwhile, Morris water maze test was used to assess spatial memory of mice at P31 (postnatal 31 days. DHA restored sevoflurane-induced decreased level of PSD95 and synaptophysin expressions and increased PSD areas and also improved long-term spatial memory. These results suggest that DHA could rescue synaptogenesis impairment and long-term memory deficits in postnatal caused by multiple sevoflurane exposures.

  6. Nicotine blocks stress-induced impairment of spatial memory and long-term potentiation of the hippocampal CA1 region.

    Aleisa, Abdulaziz M; Alzoubi, Karem H; Gerges, Nashaat Z; Alkadhi, Karim A

    2006-08-01

    The effect of chronic nicotine treatment on chronic psychosocial stress-induced impairment of short-term memory and long-term potentiation (LTP) was determined. An "intruder" stress model was used to induce psychosocial stress for 4-6 wk, during which rats were injected with saline or nicotine (1 mg/kg s.c.) twice a day. The radial arm water maze memory task was used to test hippocampus-dependent spatial memory. Chronic psychosocial stress impaired short-term memory without affecting the learning phase or long-term memory. Concurrent chronic nicotine treatment prevented stress-induced short-term memory impairment. In normal rats chronic nicotine treatment had no effect on learning and memory. Extracellular recordings from the CA1 region of anaesthetized rats showed severe reduction of LTP magnitude in stressed rats, which was normalized in nicotine-treated stressed rats. Nicotine had no effect on LTP in control animals. These results showed that chronic nicotine treatment improved hippocampus-dependent spatial memory and LTP only when impaired by stress.

  7. NF-κB p50 subunit knockout impairs late LTP and alters long term memory in the mouse hippocampus

    Oikawa Kensuke

    2012-07-01

    Full Text Available Abstract Background Nuclear factor kappa B (NF-κB is a transcription factor typically expressed with two specific subunits (p50, p65. Investigators have reported that NF-κB is activated during the induction of in vitro long term potentiation (LTP, a paradigm of synaptic plasticity and correlate of memory, suggesting that NF-κB may be necessary for some aspects of memory encoding. Furthermore, NF-κB has been implicated as a potential requirement in behavioral tests of memory. Unfortunately, very little work has been done to explore the effects of deleting specific NF-κB subunits on memory. Studies have shown that NF-κB p50 subunit deletion (p50−/− leads to memory deficits, however some recent studies suggest the contrary where p50−/− mice show enhanced memory in the Morris water maze (MWM. To more critically explore the role of the NF-κB p50 subunit in synaptic plasticity and memory, we assessed long term spatial memory in vivo using the MWM, and synaptic plasticity in vitro utilizing high frequency stimuli capable of eliciting LTP in slices from the hippocampus of NF-κB p50−/− versus their controls (p50+/+. Results We found that the lack of the NF-κB p50 subunit led to significant decreases in late LTP and in selective but significant alterations in MWM tests (i.e., some improvements during acquisition, but deficits during retention. Conclusions These results support the hypothesis that the NF-κ p50 subunit is required in long term spatial memory in the hippocampus.

  8. Spatial memory and long-term object recognition are impaired by circadian arrhythmia and restored by the GABAAAntagonist pentylenetetrazole.

    Ruby, Norman F; Fernandez, Fabian; Garrett, Alex; Klima, Jessy; Zhang, Pei; Sapolsky, Robert; Heller, H Craig

    2013-01-01

    Performance on many memory tests varies across the day and is severely impaired by disruptions in circadian timing. We developed a noninvasive method to permanently eliminate circadian rhythms in Siberian hamsters (Phodopus sungorus) [corrected] so that we could investigate the contribution of the circadian system to learning and memory in animals that are neurologically and genetically intact. Male and female adult hamsters were rendered arrhythmic by a disruptive phase shift protocol that eliminates cycling of clock genes within the suprachiasmatic nucleus (SCN), but preserves sleep architecture. These arrhythmic animals have deficits in spatial working memory and in long-term object recognition memory. In a T-maze, rhythmic control hamsters exhibited spontaneous alternation behavior late in the day and at night, but made random arm choices early in the day. By contrast, arrhythmic animals made only random arm choices at all time points. Control animals readily discriminated novel objects from familiar ones, whereas arrhythmic hamsters could not. Since the SCN is primarily a GABAergic nucleus, we hypothesized that an arrhythmic SCN could interfere with memory by increasing inhibition in hippocampal circuits. To evaluate this possibility, we administered the GABAA antagonist pentylenetetrazole (PTZ; 0.3 or 1.0 mg/kg/day) to arrhythmic hamsters for 10 days, which is a regimen previously shown to produce long-term improvements in hippocampal physiology and behavior in Ts65Dn (Down syndrome) mice. PTZ restored long-term object recognition and spatial working memory for at least 30 days after drug treatment without restoring circadian rhythms. PTZ did not augment memory in control (entrained) animals, but did increase their activity during the memory tests. Our findings support the hypothesis that circadian arrhythmia impairs declarative memory by increasing the relative influence of GABAergic inhibition in the hippocampus.

  9. Accelerated forgetting? An evaluation on the use of long-term forgetting rates in patients with memory problems

    Sofie eGeurts

    2015-06-01

    Full Text Available The main focus of this review was to evaluate whether long-term forgetting rates (delayed tests days to weeks after initial learning are a more sensitive measure to detect memory problems in various patient groups than standard delayed recall measures. It has been suggested that accelerated forgetting might be characteristic for epilepsy patients, but little research has been performed within other populations. Here, we identified ten studies in a wide range of brain injured patient groups, whose long-term forgetting patterns were compared to that of healthy controls. Signs of accelerated forgetting were found within two studies. The results of seven studies showed normal forgetting over time for the patient groups. However, most of the studies used only a recognition procedure, after optimizing initial learning. Based on the results, we discuss recommendations for assessing long-term forgetting and the need for future research to truly evaluate the usefulness for clinical practice.

  10. A novel role for extracellular signal-regulated kinase in maintaining long-term memory-relevant excitability changes.

    Cohen-Matsliah, Sivan Ida; Brosh, Inbar; Rosenblum, Kobi; Barkai, Edi

    2007-11-14

    Pyramidal neurons in the piriform cortex from olfactory-discrimination-trained rats show enhanced intrinsic neuronal excitability that lasts for several days after learning. Such enhanced intrinsic excitability is mediated by long-term reduction in the postburst afterhyperpolarization (AHP), which is generated by repetitive spike firing. AHP reduction is attributable to decreased conductance of a calcium-dependent potassium current, the sI(AHP). We have previously shown that such learning-induced AHP reduction is maintained by PKC activation. However, the molecular machinery underlying such long-lasting modulation of intrinsic excitability is yet to be fully described. Here we examine whether the extracellular signal-regulated kinase I/II (ERKI/II) pathway, which is known to be crucial in learning, memory, and synaptic plasticity processes, is instrumental for the long-term maintenance of learning-induced AHP reduction. PD98059 or UO126, which selectively block MEK, the upstream kinase of ERK, increased the AHP in neurons from trained rats but not in neurons from naive and pseudo-trained rats. Consequently, the differences in AHP amplitude and neuronal adaptation between neurons from trained rats and controls were abolished. This effect was not mediated by modulation of basic membrane properties. In accordance with its effect on neuronal excitability, the level of activated ERK in the membranal fraction was significantly higher in piriform cortex samples taken from trained rats. In addition, the PKC activator OAG (1-oleoyl-20acety-sn-glycerol), which was shown to reduce the AHP in neurons from control rats, had no effect on these neurons in the presence of PD98059. Our data show that ERK has a key role in maintaining long-lasting learning-induced enhancement of neuronal excitability.

  11. Forebrain NR2B overexpression facilitating the prefrontal cortex long-term potentiation and enhancing working memory function in mice.

    Yihui Cui

    Full Text Available Prefrontal cortex plays an important role in working memory, attention regulation and behavioral inhibition. Its functions are associated with NMDA receptors. However, there is little information regarding the roles of NMDA receptor NR2B subunit in prefrontal cortical synaptic plasticity and prefrontal cortex-related working memory. Whether the up-regulation of NR2B subunit influences prefrontal cortical synaptic plasticity and working memory is not yet clear. In the present study, we measured prefrontal cortical synaptic plasticity and working memory function in NR2B overexpressing transgenic mice. In vitro electrophysiological data showed that overexpression of NR2B specifically in the forebrain region resulted in enhancement of prefrontal cortical long-term potentiation (LTP but did not alter long-term depression (LTD. The enhanced LTP was completely abolished by a NR2B subunit selective antagonist, Ro25-6981, indicating that overexpression of NR2B subunit is responsible for enhanced LTP. In addition, NR2B transgenic mice exhibited better performance in a set of working memory paradigms including delay no-match-to-place T-maze, working memory version of water maze and odor span task. Our study provides evidence that NR2B subunit of NMDA receptor in prefrontal cortex is critical for prefrontal cortex LTP and prefrontal cortex-related working memory.

  12. Pre-learning stress that is temporally removed from acquisition exerts sex-specific effects on long-term memory.

    Zoladz, Phillip R; Warnecke, Ashlee J; Woelke, Sarah A; Burke, Hanna M; Frigo, Rachael M; Pisansky, Julia M; Lyle, Sarah M; Talbot, Jeffery N

    2013-02-01

    We have examined the influence of sex and the perceived emotional nature of learned information on pre-learning stress-induced alterations of long-term memory. Participants submerged their dominant hand in ice cold (stress) or warm (no stress) water for 3 min. Thirty minutes later, they studied 30 words, rated the words for their levels of emotional valence and arousal and were then given an immediate free recall test. Twenty-four hours later, participants' memory for the word list was assessed via delayed free recall and recognition assessments. The resulting memory data were analyzed after categorizing the studied words (i.e., distributing them to "positive-arousing", "positive-non-arousing", "negative-arousing", etc. categories) according to participants' valence and arousal ratings of the words. The results revealed that participants exhibiting a robust cortisol response to stress exhibited significantly impaired recognition memory for neutral words. More interestingly, however, males displaying a robust cortisol response to stress demonstrated significantly impaired recall, overall, and a marginally significant impairment of overall recognition memory, while females exhibiting a blunted cortisol response to stress demonstrated a marginally significant impairment of overall recognition memory. These findings support the notion that a brief stressor that is temporally separated from learning can exert deleterious effects on long-term memory. However, they also suggest that such effects depend on the sex of the organism, the emotional salience of the learned information and the degree to which stress increases corticosteroid levels.

  13. 2015 Long-Term Hydrologic Monitoring Program Sampling and Analysis Results at Rio Blanco, Colorado

    Findlay, Rick [Nararro Research and Engineering, Oak Ridge, TN (United States); Kautsky, Mark [US Department of Energy, Washington, DC (United States). Office of Legacy Management

    2015-12-01

    The U.S. Department of Energy (DOE) Office of Legacy Management conducted annual sampling at the Rio Blanco, Colorado, Site for the Long-Term Hydrologic Monitoring Program (LTHMP) on May 20–21, 2015. This report documents the analytical results of the Rio Blanco annual monitoring event, the trip report, and the data validation package. The groundwater and surface water monitoring samples were shipped to the GEL Group Inc. laboratories for conventional analysis of tritium and analysis of gamma-emitting radionuclides by high-resolution gamma spectrometry. A subset of water samples collected from wells near the Rio Blanco site was also sent to GEL Group Inc. for enriched tritium analysis. All requested analyses were successfully completed. Samples were collected from a total of four onsite wells, including two that are privately owned. Samples were also collected from two additional private wells at nearby locations and from nine surface water locations. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry, and they were analyzed for tritium using the conventional method with a detection limit on the order of 400 picocuries per liter (pCi/L). Four locations (one well and three surface locations) were analyzed using the enriched tritium method, which has a detection limit on the order of 3 pCi/L. The enriched locations included the well at the Brennan Windmill and surface locations at CER-1, CER-4, and Fawn Creek 500 feet upstream.

  14. Long-term memory consolidation: The role of RNA-binding proteins with prion-like domains.

    Sudhakaran, Indulekha P; Ramaswami, Mani

    2016-10-11

    Long-term and short-term memories differ primarily in the duration of their retention. At a molecular level, long-term memory (LTM) is distinguished from short-term memory (STM) by its requirement for new gene expression. In addition to transcription (nuclear gene expression) the translation of stored mRNAs is necessary for LTM formation. The mechanisms and functions for temporal and spatial regulation of mRNAs required for LTM is a major contemporary problem, of interest from molecular, cell biological, neurobiological and clinical perspectives. This review discusses primary evidence in support for translational regulatory events involved in LTM and a model in which different phases of translation underlie distinct phases of consolidation of memories. However, it focuses largely on mechanisms of memory persistence and the role of prion-like domains in this defining aspect of long-term memory. We consider primary evidence for the concept that Cytoplasmic Polyadenylation Element Binding (CPEB) protein enables the persistence of formed memories by transforming in prion-like manner from a soluble monomeric state to a self-perpetuating and persistent polymeric translationally active state required for maintaining persistent synaptic plasticity. We further discuss prion-like domains prevalent on several other RNA-binding proteins involved in neuronal translational control underlying LTM. Growing evidence indicates that such RNA regulatory proteins are components of mRNP (RiboNucleoProtein) granules. In these proteins, prion-like domains, being intrinsically disordered, could mediate weak transient interactions that allow the assembly of RNP granules, a source of silenced mRNAs whose translation is necessary for LTM. We consider the structural bases for RNA granules formation as well as functions of disordered domains and discuss how these complicate the interpretation of existing experimental data relevant to general mechanisms by which prion-domain containing RBPs

  15. A Transcription Factor-Binding Domain of the Coactivator CBP Is Essential for Long-Term Memory and the Expression of Specific Target Genes

    Oliveira, Ana M. M.; Brindle, Paul K.; Abel, Ted; Wood, Marcelo A.; Attner, Michelle A.

    2006-01-01

    Transcriptional activation is a key process required for long-term memory formation. Recently, the transcriptional coactivator CREB-binding protein (CBP) was shown to be critical for hippocampus-dependent long-term memory and hippocampal synaptic plasticity. As a coactivator with intrinsic histone acetyltransferase activity, CBP interacts with…

  16. Effects of Sleep Deprivation and Aging on Long-Term and Remote Memory in Mice

    Vecsey, Christopher G.; Park, Alan J.; Khatib, Nora; Abel, Ted

    2015-01-01

    Sleep deprivation (SD) following hippocampus-dependent learning in young mice impairs memory when tested the following day. Here, we examined the effects of SD on remote memory in both young and aged mice. In young mice, we found that memory is still impaired 1 mo after training. SD also impaired memory in aged mice 1 d after training, but, by a…

  17. 2015 Long-Term Hydrologic Monitoring Program Sampling and Analysis Results Report for Project Rulison, Co

    Findlay, Rick [Navarro Research and Engineering, Oak Ridge, TN (United States); Kautsky, Mark [US Department of Energy, Washington, DC (United States). Office of Legacy Management

    2015-12-01

    The U.S. Department of Energy (DOE) Office of Legacy Management conducted annual sampling at the Rulison, Colorado, Site for the Long-Term Hydrologic Monitoring Program (LTHMP) on May 20–22 and 27, 2015. Several of the land owners were not available to allow access to their respective properties, which created the need for several sample collection trips. This report documents the analytical results of the Rulison monitoring event and includes the trip report and the data validation package (Appendix A). The groundwater and surface water monitoring were shipped to the GEL Group Inc. laboratories for analysis. All requested analyses were successfully completed. Samples were analyzed for gamma-emitting radionuclides by high- resolution gamma spectrometry. Tritium was analyzed using two methods, the conventional tritium method, which has a detection limit on the order of 400 picocuries per liter (pCi/L), and the enriched method (for selected samples), which has a detection limit on the order of 3 pCi/L.

  18. Long-term effects of an acute and systemic administration of LPS on adult neurogenesis and spatial memory

    Jorge eValero

    2014-04-01

    Full Text Available The cognitive reserve is the capacity of the brain to maintain normal performance while exposed to insults or ageing. Increasing evidences point to a role for the interaction between inflammatory conditions and cognitive reserve status during Alzheimer's disease (AD progression. The production of new neurons along adult life can be considered as one of the components of the cognitive reserve. Interestingly, adult neurogenesis is decreased in mouse models of AD and following inflammatory processes. The aim of this work is to reveal the long-term impact of a systemic inflammatory event on memory and adult neurogenesis in wild type (WT and triple transgenic mouse model of AD (3xTg-AD.4 month-old mice were intraperitoneally injected once with saline or lipopolysaccharide (LPS and their performance on spatial memory analyzed with the Morris water maze (MWM test 7 weeks later. Our data showed that a single intraperitoneal injection with LPS has a long-term impact in the production of hippocampal neurons. Consistently, LPS-treated WT mice showed less doublecortin-positive neurons, less synaptic contacts in newborn neurons, and decreased dendritic volume and complexity. These surprising observations were accompanied with memory deficits. 3xTg-AD mice showed a decrease in new neurons in the dentate gyrus compatible with, although exacerbated, the pattern observed in WT LPS-treated mice. In 3xTg-AD mice, LPS injection did not significantly affected the production of new neurons but reduced their number of synaptic puncta and impaired memory performance, when compared to the observations made in saline-treated 3xTg-AD mice. These data indicate that LPS treatment induces a long-term impairment on hippocampal neurogenesis and memory. Our results show that acute neuroinflammatory events influence the production of new hippocampal neurons, affecting the cognitive reserve and leading to the development of memory deficits associated to Alzheimer's disease

  19. On the interplay between short and long term memory in the power-law cross-correlations setting

    Kristoufek, Ladislav

    2015-03-01

    We focus on emergence of the power-law cross-correlations from processes with both short and long term memory properties. In the case of correlated error-terms, the power-law decay of the cross-correlation function comes automatically with the characteristics of separate processes. Bivariate Hurst exponent is then equal to an average of separate Hurst exponents of the analyzed processes. Strength of short term memory has no effect on these asymptotic properties. Implications of these findings for the power-law cross-correlations concept are further discussed.

  20. Translational control by eIF2α kinases in long-lasting synaptic plasticity and long-term memory.

    Trinh, Mimi A; Klann, Eric

    2013-10-01

    Although the requirement for new protein synthesis in synaptic plasticity and memory has been well established, recent genetic, molecular, electrophysiological, and pharmacological studies have broadened our understanding of the translational control mechanisms that are involved in these processes. One of the critical translational control points mediating general and gene-specific translation depends on the phosphorylation of eukaryotic initiation factor 2 alpha (eIF2α) by four regulatory kinases. Here, we review the literature highlighting the important role for proper translational control via regulation of eIF2α phosphorylation by its kinases in long-lasting synaptic plasticity and long-term memory.

  1. The Comparison between Contextual Guessing Strategies vs. Memorizing a List of Isolated Words in Vocabulary Learning Regarding Long Term Memory

    Leyla Vakili S AMIYAN

    2014-03-01

    Full Text Available Guessing the meaning of unknown vocabularies within a text is a way of learning new words which is named textual vocabulary acquisition. The main purpose of this study is to investigate the effectiveness of a textual guessing strategy on vocabulary learning at the intermediate le vel. Textual guessing strategy is to guess the meaning of vocabularies with the help of surrounding words or sentences in the co - text without any translation. This paper reports the findings of two quantitative studies conducted on English language learner s with the Intermediate 2 level of proficiency in Kavosh foreign language institute, Mashhad, Iran. Twenty male and female attendants were selected and assigned to ’context’ and ‘non - context’ groups. The context group received an instruction to infer the m eaning of new words while the non - context participants were treated as learning new vocabularies individually (autonomously. The result of the independent sample t - test at the post - test stage revealed that the probability value of t - test with an equality of variances assumption is lower than 0.05 (0.04700. So this result represented that there is a meaningful difference between the experimental group and the control group considering their amount of learning. The results indicated that textual guessing s trategy had more effect on their long term memory. It was also revealed that the words learned through context are used more frequently than those learned in isolation in the speaking repertoire of the participants.

  2. Long-term persistence of T cell memory to HBsAg after hepatitis B vaccination

    Ru-Xiang Wang; Greet J. Boland; Jan van Hattum; Gijsbert C. de Gast

    2004-01-01

    AIM: To determine if the T cell memory to HBsAg can persist for a long time after hepatitis B (HB) vaccination.METHODS: Thirty one vaccine recipients who were healthcare workers (18 females and 13 males aged 34-58 years) from Utrecht University Hospital, Netherlands, and had previously Received a standard course of vaccination for hepatitis B were investigated and another 9 unvaccinated healthy volunteers from the same hospital were used as the control. Blood samples were taken just before the experiment to test serum anti-HBs levels and the subjects were classified into different groups according to their serum titers of anti-HBs and vaccination history. Their peripheral blood mononuclear cells (pBrvMc) were isolated from freshly heparinized venous blood and the proliferative response of Tlymphocytes to the recombinant hepatitis B surface antigen(HBsAg) was investigated.RESULTS: Positive serum anti-HBs was found in 61.3%(19/31) vaccine recipients and a significant in vitro lymphocyte proliferative response to recombinant HBsAg was observed in all the vaccinees with positive anti-HBs. Serum anti-HBs level ≤10 IU/L was found in 38.7% (12/31)subjects. In this study, we specially focused on lymphocyte proliferative response to recombinant HBsAg in those vaccine recipients with serum anti-HBsAg less than 10 IU/L.Most of them had Received a standard course of vaccination about 10 years before. T lymphocyte proliferative response was found positive in 7 of the 12 vaccine recipients. These results confirmed that HBsAg-specific memory T cells remained detectable in the circulation for a long time after vaccination, even when serum anti-HBs level had been undetectable.CONCLUSION: The T cell memory to HBsAg can persist for at least 10 years after HB vaccination. Further booster injection is not necessary in healthy responders to HB vaccine.

  3. Effects of pre-encoding stress on brain correlates associated with the long-term memory for emotional scenes.

    Janine Wirkner

    Full Text Available Recent animal and human research indicates that stress around the time of encoding enhances long-term memory for emotionally arousing events but neural evidence remains unclear. In the present study we used the ERP old/new effect to investigate brain dynamics underlying the long-term effects of acute pre-encoding stress on memory for emotional and neutral scenes. Participants were exposed either to the Socially Evaluated Cold Pressure Test (SECPT or a warm water control procedure before viewing 30 unpleasant, 30 neutral and 30 pleasant pictures. Two weeks after encoding, recognition memory was tested using 90 old and 90 new pictures. Emotional pictures were better recognized than neutral pictures in both groups and related to an enhanced centro-parietal ERP old/new difference (400-800 ms during recognition, which suggests better recollection. Most interestingly, pre-encoding stress exposure specifically increased the ERP old/new-effect for emotional (unpleasant pictures, but not for neutral pictures. These enhanced ERP/old new differences for emotional (unpleasant scenes were particularly pronounced for those participants who reported high levels of stress during the SECPT. The results suggest that acute pre-encoding stress specifically strengthens brain signals of emotional memories, substantiating a facilitating role of stress on memory for emotional scenes.

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

    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.

  5. The role of reconsolidation and the dynamic process of long-term memory formation and storage

    Cristina M Alberini

    2011-03-01

    Full Text Available It is becoming increasingly clear that the processes of memory formation and storage are exquisitely dynamic. Elucidating the nature and temporal evolution of the biological changes that accompany encoding, storage and retrieval is key to understand memory formation. For explicit or medial temporal lobe-dependent memories that form after a discrete event and are stored for a long time, the physical changes underlying the encoding and processing of the information (memory trace or engram remain in a fragile state for some time. However, over time, the new memory becomes increasingly resistant to disruption until it is consolidated. Retrieval or reactivation of an apparently consolidated memory can render the memory labile again, and reconsolidation is the process that occurs to mediate its restabilization. Reconsolidation also evolves with the age of the memory: Young memories are sensitive to postreactivation disruption, but older memories are more resistant. Why does a memory become labile again if it is retrieved or reactivated? Here I suggest that the main function of reconsolidation is to contribute to the lingering consolidation process and mediate memory strengthening. I also discuss the literature and results regarding the influence of the passage of time on the reconsolidation of memory. These points have important implications for the use of reconsolidation in therapeutic settings.

  6. Intermediate and long-term memories of associative learning are differentially affected by transcription versus translation blockers in Lymnaea.

    Sangha, Susan; Scheibenstock, Andi; McComb, Chloe; Lukowiak, Ken

    2003-05-01

    Aerial respiratory behaviour in the pond snail, Lymnaea stagnalis, can be operantly conditioned. This associative learning then undergoes consolidation into a long-lasting memory which, depending on the training procedure used, causes intermediate-term memory (ITM; lasting 3 h) or long-term memory (LTM; lasting >6 h) to be formed. We determined the differential susceptibility of these two forms of memory to translation and transcription blockers. The injection of a translation blocker, Anisomycin, 2.5 h before training prevents the establishment of both ITM and LTM. On the other hand, injection of the transcription blocker Actinomycin D, 2.5 h before training, did not prevent the establishment of ITM, but did, however, prevent LTM formation. Thus in Lymnaea, following associative learning, both ITM and LTM are dependent on new protein synthesis. ITM appears to be dependent on protein synthesis from preexisting transcription factors, whilst LTM is dependent on protein synthesis from new transcription messages.

  7. Homologue of Protein Kinase Mζ Maintains Context Aversive Memory and Underlying Long-Term Facilitation in Terrestrial Snail Helix.

    Pavel M. Balaban

    2015-06-01

    Full Text Available It has been shown that a variety of long-term memories in different regions of the brain and in different species are quickly erased by local inhibition of PKMζ. Using antibodies to mammalian PKMζ, we describe in the present study the localization of immunoreactive molecules in the nervous system of the terrestrial snail Helix lucorum. Presence of a homologue of PKMζ was confirmed with transcriptomics. We have demonstrated in behavioral experiments that contextual fear memory disappeared under a blockade of PKMζ with a selective peptide blocker of PKMζ (ZIP, but not with scrambled ZIP. If ZIP was combined with a reminder (20 min in noxious context, no impairment of the long-term contextual memory was observed. In electrophysiological experiments we investigated whether PKMζ takes part in the maintenance of long-term facilitation (LTF in the neural circuit mediating tentacle withdrawal. LTF of excitatory synaptic inputs to premotor interneurons was induced by high-frequency nerve stimulation combined with serotonin bath applications and lasted at least four hours. We found that bath application of 2x10-6 M ZIP at the 90th min after the tetanization reduced the EPSP amplitude to the non-tetanized EPSP values. Applications of the scrambled ZIP peptide at a similar time and concentration didn't affect the EPSP amplitudes. In order to test whether effects of ZIP are specific to the synapses, we performed experiments with LTF of somatic membrane responses to local glutamate applications. It was shown earlier that serotonin application in such an artificial synapse condition elicits LTF of responses to glutamate. It was found that ZIP had no effect on LTF in these conditions, which may be explained by the very low concentration of PKMζ molecules in somata of these identified neurons, as evidenced by immunochemistry. Obtained results suggest that the Helix homologue of PKMζ might be involved in post-induction maintenance of long-term changes in

  8. Uncertainties in Air Exchange using Continuous-Injection, Long-Term Sampling Tracer-Gas Methods

    Sherman, Max H.; Walker, Iain S.; Lunden, Melissa M.

    2013-12-01

    The PerFluorocarbon Tracer (PFT) method is a low-cost approach commonly used for measuring air exchange in buildings using tracer gases. It is a specific application of the more general Continuous-Injection, Long-Term Sampling (CILTS) method. The technique is widely used but there has been little work on understanding the uncertainties (both precision and bias) associated with its use, particularly given that it is typically deployed by untrained or lightly trained people to minimize experimental costs. In this article we will conduct a first-principles error analysis to estimate the uncertainties and then compare that analysis to CILTS measurements that were over-sampled, through the use of multiple tracers and emitter and sampler distribution patterns, in three houses. We find that the CILTS method can have an overall uncertainty of 10-15percent in ideal circumstances, but that even in highly controlled field experiments done by trained experimenters expected uncertainties are about 20percent. In addition, there are many field conditions (such as open windows) where CILTS is not likely to provide any quantitative data. Even avoiding the worst situations of assumption violations CILTS should be considered as having a something like a ?factor of two? uncertainty for the broad field trials that it is typically used in. We provide guidance on how to deploy CILTS and design the experiment to minimize uncertainties.

  9. Mind racing: The influence of exercise on long-term memory consolidation.

    McNerney, M Windy; Radvansky, Gabriel A

    2015-01-01

    Over time, regular exercise can lower the risk for age-related decline in cognition. However, the immediate effects of exercise on memory consolidation in younger adults have not been fully investigated. In two experiments, the effects of exercise were assessed on three different memory tasks. These included paired-associate learning, procedural learning and text memory. Results indicate that performance on procedural learning and situation model memory was increased with exercise, regardless of if participants exercised before or after encoding. No benefit of exercise was found for paired-associate learning. These findings suggest that intense exercise may benefit certain types of memory consolidation.

  10. The Sleep Elaboration-Awake Pruning (SEAP) theory of memory: long term memories grow in complexity during sleep and undergo selection while awake. Clinical, psychopharmacological and creative implications.

    Charlton, Bruce G; Andras, Peter

    2009-07-01

    Long term memory (LTM) systems need to be adaptive such that they enhance an organism's reproductive fitness and self-reproducing in order to maintain their complexity of communications over time in the face of entropic loss of information. Traditional 'representation-consolidation' accounts conceptualize memory adaptiveness as due to memories being 'representations' of the environment, and the longevity of memories as due to 'consolidation' processes. The assumption is that memory representations are formed while an animal is awake and interacting with the environment, and these memories are consolidated mainly while the animal is asleep. So the traditional view of memory is 'instructionist' and assumes that information is transferred from the environment into the brain. By contrast, we see memories as arising endogenously within the brain's LTM system mainly during sleep, to create complex but probably maladaptive memories which are then simplified ('pruned') and selected during the awake period. When awake the LTM system is brought into a more intense interaction with past and present experience. Ours is therefore a 'selectionist' account of memory, and could be termed the Sleep Elaboration-Awake Pruning (or SEAP) theory. The SEAP theory explains the longevity of memories in the face of entropy by the tendency for memories to grow in complexity during sleep; and explains the adaptiveness of memory by selection for consistency with perceptions and previous memories during the awake state. Sleep is therefore that behavioural state during which most of the internal processing of the system of LTM occurs; and the reason sleep remains poorly understood is that its primary activity is the expansion of long term memories. By re-conceptualizing the relationship between memory, sleep and the environment; SEAP provides a radically new framework for memory research, with implications for the measurement of memory and the design of empirical investigations in clinical

  11. Long-term memory: a natural mechanism for the clustering of extreme events and anomalous residual times in climate records.

    Bunde, Armin; Eichner, Jan F; Kantelhardt, Jan W; Havlin, Shlomo

    2005-02-04

    We study the statistics of the return intervals between extreme events above a certain threshold in long-term persistent records. We find that the long-term memory leads (i) to a stretched exponential distribution of the return intervals, (ii) to a pronounced clustering of extreme events, and (iii) to an anomalous behavior of the mean residual time to the next event that depends on the history and increases with the elapsed time in a counterintuitive way. We present an analytical scaling approach and demonstrate that all these features can be seen in long climate records. The phenomena should also occur in heartbeat records, Internet traffic, and stock market volatility and have to be taken into account for an efficient risk evaluation.

  12. Accelerated forgetting? An evaluation on the use of long-term forgetting rates in patients with memory problems

    Geurts, Sofie; van der Werf, Sieberen P.; Kessels, Roy P. C.

    2015-01-01

    The main focus of this review was to evaluate whether long-term forgetting rates (delayed tests, days, to weeks, after initial learning) are more sensitive measures than standard delayed recall measures to detect memory problems in various patient groups. It has been suggested that accelerated forgetting might be characteristic for epilepsy patients, but little research has been performed in other populations. Here, we identified eleven studies in a wide range of brain injured patient groups, whose long-term forgetting patterns were compared to those of healthy controls. Signs of accelerated forgetting were found in three studies. The results of eight studies showed normal forgetting over time for the patient groups. However, most of the studies used only a recognition procedure, after optimizing initial learning. Based on these results, we recommend the use of a combined recall and recognition procedure to examine accelerated forgetting and we discuss the relevance of standard and optimized learning procedures in clinical practice. PMID:26106343

  13. Physical exercise prevents short and long-term deficits on aversive and recognition memory and attenuates brain oxidative damage induced by maternal deprivation.

    Neves, Ben-Hur; Menezes, Jefferson; Souza, Mauren Assis; Mello-Carpes, Pâmela B

    2015-12-01

    It is known from previous research that physical exercise prevents long-term memory deficits induced by maternal deprivation in rats. But we could not assume similar effects of physical exercise on short-term memory, as short- and long-term memories are known to result from some different memory consolidation processes. Here we demonstrated that, in addition to long-term memory deficit, the short-term memory deficit resultant from maternal deprivation in object recognition and aversive memory tasks is also prevented by physical exercise. Additionally, one of the mechanisms by which the physical exercise influences the memory processes involves its effects attenuating the oxidative damage in the maternal deprived rats' hippocampus and prefrontal cortex.

  14. Olfaction, Emtion & the Amygdala: arousal-dependent modulation of long-term autobiographical memory and its association with olfaction

    Mark Hughes

    2004-01-01

    Full Text Available The sense of smell is set apart from other sensory modalities. Odours possess the capacity to trigger immediately strong emotional memories. Moreover, odorous stimuli provide a higher degree of memory retention than other sensory stimuli. Odour perception, even in its most elemental form - olfaction - already involves limbic structures. This early involvement is not paralleled in other sensory modalities. Bearing in mind the considerable connectivity with limbic structures, and the fact that an activation of the amygdala is capable of instantaneously evoking emotions and facilitating the encoding of memories, it is unsurprising that the sense of smell has its characteristic nature. The aim of this review is to analyse current understanding of higher olfactory information processing as it relates to the ability of odours to spontaneously cue highly vivid, affectively toned, and often very old autobiographical memories (episodes known anecdotally as Proust phenomena. Particular emphasis is placed on the diversity of functions attributed to the amygdala. Its role in modulating the encoding and retrieval of long-term memory is investigated with reference to lesion, electrophysiological, immediate early gene, and functional imaging studies in both rodents and humans. Additionally, the influence of hormonal modulation and the adrenergic system on emotional memory storage is outlined. I finish by proposing a schematic of some of the critical neural pathways that underlie the odour-associated encoding and retrieval of emotionally toned autobiographical memories.

  15. Adaptation of postural control to perturbations--a process that initiates long-term motor memory.

    Tjernström, F; Fransson, P-A; Hafström, A; Magnusson, M

    2002-02-01

    The objective was to investigate postural control adaptation during daily repeated posturography with vibratory calf stimulation. The posturography was performed with eyes open and closed daily for 5 days and after 90 days on 12 healthy subjects. The postural control adaptation could be described as two separate processes, a rapid adaptation during the test progress and a long-term habituation between consecutive test days. The adaptive improvements gained during the 5 days consecutive testing, largely remained 90 days later but seemed restricted to the same test situation. The findings suggest that balance rehabilitation should include a variety of repeated exercises, which are sufficiently long to induce habituation.

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

    R. Zeelenberg (René); D. Pecher (Diane)

    2002-01-01

    textabstractSemantic 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 resul

  17. Subjective memory ability and long-term forgetting in patients referred for neuropsychological assessment

    Werf, S.P. van der; Geurts, S.; Werd, M.M.E. de

    2016-01-01

    It has been suggested that the memory complaints of patients who are not impaired on formal memory tests may reflect accelerated forgetting. We examined this hypothesis by comparing the 1-week delayed recall and recognition test performance of outpatients who were referred for neuropsychological ass

  18. Long-Term Memory Shapes the Primary Olfactory Center of an Insect Brain

    Hourcade, Benoit; Perisse, Emmanuel; Devaud, Jean-Marc; Sandoz, Jean-Christophe

    2009-01-01

    The storage of stable memories is generally considered to rely on changes in the functional properties and/or the synaptic connectivity of neural networks. However, these changes are not easily tractable given the complexity of the learning procedures and brain circuits studied. Such a search can be narrowed down by studying memories of specific…

  19. The representational consequences of intentional forgetting: Impairments to both the probability and fidelity of long-term memory.

    Fawcett, Jonathan M; Lawrence, Michael A; Taylor, Tracy L

    2016-01-01

    We investigated whether intentional forgetting impacts only the likelihood of later retrieval from long-term memory or whether it also impacts the fidelity of those representations that are successfully retrieved. We accomplished this by combining an item-method directed forgetting task with a testing procedure and modeling approach inspired by the delayed-estimation paradigm used in the study of visual short-term memory (STM). Abstract or concrete colored images were each followed by a remember (R) or forget (F) instruction and sometimes by a visual probe requiring a speeded detection response (E1-E3). Memory was tested using an old-new (E1-E2) or remember-know-no (E3) recognition task followed by a continuous color judgment task (E2-E3); a final experiment included only the color judgment task (E4). Replicating the existing literature, more "old" or "remember" responses were made to R than F items and RTs to postinstruction visual probes were longer following F than R instructions. Color judgments were more accurate for successfully recognized or recollected R than F items (E2-E3); a mixture model confirmed a decrease to both the probability of retrieving the F items as well as the fidelity of the representation of those F items that were retrieved (E4). We conclude that intentional forgetting is an effortful process that not only reduces the likelihood of successfully encoding an item for later retrieval, but also produces an impoverished memory trace even when those items are retrieved; these findings draw a parallel between the control of memory representations within working and long-term memory.

  20. Technical Note: Long-term memory effect in the atmospheric CO2 concentration at Mauna Loa

    C. Varotsos

    2007-01-01

    Full Text Available The monthly mean values of the atmospheric carbon dioxide concentration derived from in-situ air samples collected at Mauna Loa Observatory, Hawaii, USA during 1958–2004 (the longest continuous record available in the world are analyzed by employing the detrended fluctuation analysis to detect scaling behavior in this time series. The main result is that the fluctuations of carbon dioxide concentrations exhibit long-range power-law correlations (long memory with lag times ranging from four months to eleven years, which correspond to 1/f noise. This result indicates that random perturbations in the carbon dioxide concentrations give rise to noise, characterized by a frequency spectrum following a power-law with exponent that approaches to one; the latter shows that the correlation times grow strongly. This feature is pointing out that a correctly rescaled subset of the original time series of the carbon dioxide concentrations resembles the original time series. Finally, the power-law relationship derived from the real measurements of the carbon dioxide concentrations could also serve as a tool to improve the confidence of the atmospheric chemistry-transport and global climate models.

  1. Technical Note: Long-term memory effect in the atmospheric CO2 concentration at Mauna Loa

    M. Efstathiou

    2006-11-01

    Full Text Available The monthly mean values of the atmospheric carbon dioxide concentration derived from in-situ air samples collected at Mauna Loa Observatory, Hawaii, during 1958–2004 (the longest continuous record available in the world are analyzed by employing the detrended fluctuation analysis to detect scaling behavior in this time series. The main result is that the fluctuations of carbon dioxide concentrations exhibit long-range power-law correlations (long memory with lag times ranging from four months to eleven years, which correspond to 1/f noise. This result indicates that random perturbations in the carbon dioxide concentrations give rise to noise, characterized by a frequency spectrum following a power-law with exponent that approaches to one; the latter shows that the correlation times grow strongly. This feature is pointing out that a correctly rescaled subset of the original time series of the carbon dioxide concentrations resembles the original time series. Finally, the power-law relationship derived from the real measurements of the carbon dioxide concentrations could also serve as a tool to improve the confidence of the atmospheric chemistry-transport and global climate models.

  2. Attention Problems, Phonological Short-Term Memory, and Visuospatial Short-Term Memory: Differential Effects on Near- and Long-Term Scholastic Achievement

    Sarver, Dustin E.; Rapport, Mark D.; Kofler, Michael J.; Scanlan, Sean W.; Raiker, Joseph S.; Altro, Thomas A.; Bolden, Jennifer

    2012-01-01

    The current study examined individual differences in children's phonological and visuospatial short-term memory as potential mediators of the relationship among attention problems and near- and long-term scholastic achievement. Nested structural equation models revealed that teacher-reported attention problems were associated negatively with…

  3. [Musical long-term memory throughout the progression of Alzheimer disease].

    Groussard, Mathilde; Mauger, Caroline; Platel, Hervé

    2013-03-01

    In Alzheimer patients with a solid musical background, isolated case-reports have reported the maintenance of remarkable musical abilities despite clear difficulties in their verbal memory and linguistic functions. These reports have encouraged a number of scientists to undertake more systematic studies which would allow a rigorous approach to the analysis of musical memory in Alzheimer patients with no formal musical background. Although restricted in number, the latest data are controversial regarding preserved musical capacities in Alzheimer patients. Our current review of the literature addresses this topic and advances the hypothesis that the processes of musical memory are function of illness progression. In the earlier stages, the majority of evaluations concerned musical episodic memory and suggested a dysfunction of this memory whereas in the moderate and severe stages, musical semantic memory and implicit learning are the majority of investigations and seemed more resistant to Alzheimer disease. In summary, our current review bring to understand the memory circuits involved and highlight the necessity to adapted the investigational tools employed to conform with the severity of the signs and symptoms of progressive Alzheimer disease in order to demonstrate the preserved musical capacities.

  4. The effect of frequency and duration of training sessions on acquisition and long-term memory in dogs

    Demant, Helle; Ladewig, Jan; Balsby, Thorsten Johannes Skovbjerg

    2011-01-01

    dogs such as guide dogs and police dogs, also the training of family dogs can benefit from this knowledge. We studied the effect of frequency and duration of training sessions on acquisition and on long-term memory. Forty-four laboratory Beagles were divided into 4 groups and trained by means...... of the learned task; all groups had a high level of retention after 4 weeks. The results of the study can be used to optimize training in dogs, which is important since the number of training sessions often is a limiting factor in practical dog training. The results also suggest that, once a task is learned...

  5. Long-term effect of early-life stress from earthquake exposure on working memory in adulthood

    Li, Na; Wang, Yumei; Zhao, Xiaochuan; Gao, Yuanyuan; Song, Mei; Yu, Lulu; Wang, Lan; Li, Ning; Chen, Qianqian; Li, Yunpeng; Cai,Jiajia; Wang, Xueyi

    2015-01-01

    Objective The present study aimed to investigate the long-term effect of 1976 Tangshan earthquake exposure in early life on performance of working memory in adulthood. Methods A total of 907 study subjects born and raised in Tangshan were enrolled in this study. They were divided into three groups according to the dates of birth: infant exposure (3–12 months, n=274), prenatal exposure (n=269), and no exposure (born at least 1 year after the earthquake, n=364). The prenatal group was further d...

  6. Questioning short-term memory and its measurement: Why digit span measures long-term associative learning.

    Jones, Gary; Macken, Bill

    2015-11-01

    Traditional accounts of verbal short-term memory explain differences in performance for different types of verbal material by reference to inherent characteristics of the verbal items making up memory sequences. The role of previous experience with sequences of different types is ostensibly controlled for either by deliberate exclusion or by presenting multiple trials constructed from different random permutations. We cast doubt on this general approach in a detailed analysis of the basis for the robust finding that short-term memory for digit sequences is superior to that for other sequences of verbal material. Specifically, we show across four experiments that this advantage is not due to inherent characteristics of digits as verbal items, nor are individual digits within sequences better remembered than other types of individual verbal items. Rather, the advantage for digit sequences stems from the increased frequency, compared to other verbal material, with which digits appear in random sequences in natural language, and furthermore, relatively frequent digit sequences support better short-term serial recall than less frequent ones. We also provide corpus-based computational support for the argument that performance in a short-term memory setting is a function of basic associative learning processes operating on the linguistic experience of the rememberer. The experimental and computational results raise questions not only about the role played by measurement of digit span in cognition generally, but also about the way in which long-term memory processes impact on short-term memory functioning.

  7. Odor-enriched environment rescues long-term social memory, but does not improve olfaction in social isolated adult mice.

    Gusmão, Isabela D; Monteiro, Brisa M M; Cornélio, Guilherme O S; Fonseca, Cristina S; Moraes, Márcio F D; Pereira, Grace S

    2012-03-17

    Prolonged permanence of animals under social isolation (SI) arouses a variety of psychological symptoms like aggression, stress, anxiety and depression. However, short-term SI is commonly used to evaluate social memory. Interestingly, the social memory cannot be accessed with delays higher than 30min in SI mice. Our hypothesis is that SI with intermediate duration, like one week (1w), impairs the long-term storage of new social information (S-LTM), without affecting anxiety or other types of memories, because the SI compromises the olfactory function of the animal. Our results demonstrated that SI impaired S-LTM, without affecting other kinds of memory or anxiety. In addition, the SI increased the latency in the buried-food finding task, but did not affect the habituation or the discrimination of odors. Next, we postulated that if continuous input to the olfactory system is fundamental for the maintenance of the olfactory function and social memory persistence, isolated mice under odor-enriched environment (OEE) should behave like group-housed (GH) animals. In fact, the OEE prevented the S-LTM deficit imposed by the SI. However, OEE did not restore the SI mice olfaction to the GH mice level. Our results suggest that SI modulates olfaction and social memory persistence, probably, by independent mechanisms. We also showed for the first time that OEE rescued S-LTM in SI mice through a mechanism not necessarily involved with olfaction.

  8. Consolidation power of extrinsic rewards: reward cues enhance long-term memory for irrelevant past events.

    Murayama, Kou; Kitagami, Shinji

    2014-02-01

    Recent research suggests that extrinsic rewards promote memory consolidation through dopaminergic modulation processes. However, no conclusive behavioral evidence exists given that the influence of extrinsic reward on attention and motivation during encoding and consolidation processes are inherently confounded. The present study provides behavioral evidence that extrinsic rewards (i.e., monetary incentives) enhance human memory consolidation independently of attention and motivation. Participants saw neutral pictures, followed by a reward or control cue in an unrelated context. Our results (and a direct replication study) demonstrated that the reward cue predicted a retrograde enhancement of memory for the preceding neutral pictures. This retrograde effect was observed only after a delay, not immediately upon testing. An additional experiment showed that emotional arousal or unconscious resource mobilization cannot explain the retrograde enhancement effect. These results provide support for the notion that the dopaminergic memory consolidation effect can result from extrinsic reward.

  9. Anisomycin Injection in Area CA3 of the Hippocampus Impairs Both Short-Term and Long-Term Memories of Contextual Fear

    Remaud, Jessica; Ceccom, Johnatan; Carponcy, Julien; Dugué, Laura; Menchon, Gregory; Pech, Stéphane; Halley, Helene; Francés, Bernard; Dahan, Lionel

    2014-01-01

    Protein synthesis is involved in the consolidation of short-term memory into long-term memory. Previous electrophysiological data concerning LTP in CA3 suggest that protein synthesis in that region might also be necessary for short-term memory. We tested this hypothesis by locally injecting the protein synthesis inhibitor anisomycin in hippocampal…

  10. Food restriction increases long- term memory persistence in adult or aged mice

    Talhati, Fernanda [UNIFESP; Patti, Camila de Lima [UNIFESP; Zanin, Karina Agustini [UNIFESP; Lopes-Silva, Leonardo Brito [UNIFESP; Ceccon, Liliane Minglini Barbosa [UNIFESP; Hollais, André Willian [UNIFESP; Bizerra, Carolina Souza [UNIFESP; Santos, Renan [UNIFESP; Tufik, Sergio; Frussa-Filho, Roberto

    2014-01-01

    Food restriction (FR) seems to be the unique experimental manipulation that leads to a remarkable increase in lifespan in rodents. Evidences have suggested that FR can enhance memory in distinct animal models mainly during aging. However, only few studies systemically evaluated the effects FR on memory formation in both adult (3-month-old) and aged (18-24-month-old) mice. Thus, the aim of the present study was to investigate the effects of acute (12 h) or repeated (12 h/day for 2 days) FR pro...

  11. Long-term memory for pavlovian fear conditioning requires dopamine in the nucleus accumbens and basolateral amygdala.

    Jonathan P Fadok

    Full Text Available The neurotransmitter dopamine (DA is essential for learning in a pavlovian fear conditioning paradigm known as fear-potentiated startle (FPS. Mice lacking the ability to synthesize DA fail to learn the association between the conditioned stimulus and the fear-inducing footshock. Previously, we demonstrated that restoration of DA synthesis to neurons of the ventral tegmental area (VTA was sufficient to restore FPS. Here, we used a target-selective viral restoration approach to determine which mesocorticolimbic brain regions receiving DA signaling from the VTA require DA for FPS. We demonstrate that restoration of DA synthesis to both the basolateral amygdala (BLA and nucleus accumbens (NAc is required for long-term memory of FPS. These data provide crucial insight into the dopamine-dependent circuitry involved in the formation of fear-related memory.

  12. Long-term habituation (LTH in the crab Chasmagnathus: a model for behavioral and mechanistic studies of memory

    H. Maldonado

    1997-07-01

    Full Text Available A decade of studies on long-term habituation (LTH in the crab Chasmagnathus is reviewed. Upon sudden presentation of a passing object overhead, the crab reacts with an escape response that habituates promptly and for at least five days. LTH proved to be an instance of associative memory and showed context, stimulus frequency and circadian phase specificity. A strong training protocol (STP (³15 trials, intertrial interval (ITI of 171 s invariably yielded LTH, while a weak training protocol (WTP (£10 trials, ITI = 171 s invariably failed. STP was used with a presumably amnestic agent and WTP with a presumably hypermnestic agent. Remarkably, systemic administration of low doses was effective, which is likely to be due to the lack of an endothelial blood-brain barrier. LTH was blocked by inhibitors of protein and RNA synthesis, enhanced by protein kinase A (PKA activators and reduced by PKA inhibitors, facilitated by angiotensin II and IV and disrupted by saralasin. The presence of angiotensins and related compounds in the crab brain was demonstrated. Diverse results suggest that LTH includes two components: an initial memory produced by spaced training and mainly expressed at an initial phase of testing, and a retraining memory produced by massed training and expressed at a later phase of testing (retraining. The initial memory would be associative, context specific and sensitive to cycloheximide, while the retraining memory would be nonassociative, context independent and insensitive to cycloheximide

  13. Social Isolation During Adolescence Strengthens Retention of Fear Memories and Facilitates Induction of Late-Phase Long-Term Potentiation.

    Liu, Ji-Hong; You, Qiang-Long; Wei, Mei-Dan; Wang, Qian; Luo, Zheng-Yi; Lin, Song; Huang, Lang; Li, Shu-Ji; Li, Xiao-Wen; Gao, Tian-Ming

    2015-12-01

    Social isolation during the vulnerable period of adolescence produces emotional dysregulation that often manifests as abnormal behavior in adulthood. The enduring consequence of isolation might be caused by a weakened ability to forget unpleasant memories. However, it remains unclear whether isolation affects unpleasant memories. To address this, we used a model of associative learning to induce the fear memories and evaluated the influence of isolation mice during adolescence on the subsequent retention of fear memories and its underlying cellular mechanisms. Following adolescent social isolation, we found that mice decreased their social interaction time and had an increase in anxiety-related behavior. Interestingly, when we assessed memory retention, we found that isolated mice were unable to forget aversive memories when tested 4 weeks after the original event. Consistent with this, we observed that a single train of high-frequency stimulation (HFS) enabled a late-phase long-term potentiation (L-LTP) in the hippocampal CA1 region of isolated mice, whereas only an early-phase LTP was observed with the same stimulation in the control mice. Social isolation during adolescence also increased brain-derived neurotrophic factor (BDNF) expression in the hippocampus, and application of a tropomyosin-related kinase B (TrkB) receptor inhibitor ameliorated the facilitated L-LTP seen after isolation. Together, our results suggest that adolescent isolation may result in mental disorders during adulthood and that this may stem from an inability to forget the unpleasant memories via BDNF-mediated synaptic plasticity. These findings may give us a new strategy to prevent mental disorders caused by persistent unpleasant memories.

  14. On the scaling ranges of detrended fluctuation analysis for long-term memory correlated short series of data

    Grech, Dariusz; Mazur, Zygmunt

    2013-05-01

    We examine the scaling regime for the detrended fluctuation analysis (DFA)-the most popular method used to detect the presence of long-term memory in data and the fractal structure of time series. First, the scaling range for DFA is studied for uncorrelated data as a function of time series length L and the correlation coefficient of the linear regression R2 at various confidence levels. Next, a similar analysis for artificial short series of data with long-term memory is performed. In both cases the scaling range λ is found to change linearly-both with L and R2. We show how this dependence can be generalized to a simple unified model describing the relation λ=λ(L,R2,H) where H (1/2≤H≤1) stands for the Hurst exponent of the long range autocorrelated signal. Our findings should be useful in all applications of DFA technique, particularly for instantaneous (local) DFA where a huge number of short time series has to be analyzed at the same time, without possibility of checking the scaling range in each of them separately.

  15. Short- and long-term effects of cannabinoids on the extinction of contextual fear memory in rats.

    Pamplona, Fabrício A; Bitencourt, Rafael M; Takahashi, Reinaldo N

    2008-07-01

    Facilitation of memory extinction by manipulation of the endocannabinoid (eCB) system has been recently studied in several paradigms. Our previous results pointed to facilitation of contextual fear memory extinction by a low dose of a cannabinoid agonist, with a suggestion of short-term effects. The aim of the present study was to further investigate the effects of cannabinoid drugs in the short- and long-term extinction of conditioned fear using an extended extinction protocol. Male Wistar rats were placed in a conditioning chamber and after 3min received a footshock (1.5mA, 1s). On the next day, they received i.p. drug treatment (WIN55212-2 0.25mg/kg, AM404 10mg/kg, SR141716A 1mg/kg) and were re-exposed to the conditioning chamber for 30min (extinction training). No-Extinction groups received the same drug treatment, but were exposed for 3min to the conditioning chamber. A drug-free test of contextual memory (3min) was performed 7 days later. The cannabinoid agonist WI55212-2 and the inhibitor of eCB metabolism/uptake AM404 facilitated short-term extinction. In addition, long-term effects induced by treatments with WIN55212 and AM404 were completely divergent to those of SR141716A treatment. The present results confirm and extend previous findings showing that the eCB system modulates short-term fear memory extinction with long-lasting consequences.

  16. ROLE OF NEUROTRANSMITTERS AND PROTEIN SYNTHESIS IN SHORT- AND LONG-TERM MEMORY

    Bennett, E.L.; Rosenzweig, M.R.; Flood, J.F.

    1978-10-01

    Anisomycin is an effective inhibitor of cerebral protein synthesis in mice and is also an effective amnestic agent for both passive and active behavioral tasks. From use of anisomycin in combination with a variety of stimulant and depressant drugs, we conclude that the level of arousal following acquisition plays an important role in determining the duration and the rate of the biosynthetic phase of memory formation. While we have interpreted the experiments with anisomycin as evidence for an essential role of protein in memory storage, others have suggested that side effects of inhibitors of protein synthesis on catecholamine metabolism are the main cause of amnesia. Several experiments were therefore done to compare the effects of anisemycin and catecholamine inhibitors on memory. We conclude that anisomycin's principal amnestic mechanism does not involve inhibition of the catecholamine system. The results strengthen our conclusion that protein synthesis is an essential component for longterm memory trace formation. Also, it is suggested that proteins synthesized in the neuronal cell body are used, in conjunction with other molecules, to produce permanent and semi-permanent anatomical changes.

  17. CREB binding protein is required for both short-term and long-term memory formation

    Chen, G.; Zou, X.; Watanabe, H.; Deursen, J.M.A. van; Shen, J.

    2010-01-01

    CREB binding protein (CBP) is a transcriptional coactivator with histone acetyltransferase activity. Our prior study suggested that CBP might be a key target of presenilins in the regulation of memory formation and neuronal survival. To elucidate the role of CBP in the adult brain, we generated cond

  18. Reconsolidation of a Context Long-Term Memory in the Terrestrial Snail Requires Protein Synthesis

    Gainutdinova, Tatiana H.; Tagirova, Rosa R.; Ismailova, Asja I.; Muranova, Lyudmila N.; Samarova, Elena I.; Gainutdinov, Khalil L.; Balaban, Pavel M.

    2005-01-01

    We investigated the influence of the protein synthesis blocker anisomycin on contextual memory in the terrestrial snail "Helix." Prior to the training session, the behavioral responses in two contexts were similar. Two days after a session of electric shocks (5 d) in one context only, the context conditioning was observed as the significant…

  19. A Long-Term Memory Competitive Process Model of a Common Procedural Error

    2013-08-01

    A novel computational cognitive model explains human procedural error in terms of declarative memory processes. This is an early version of a process ... model intended to predict and explain multiple classes of procedural error a priori. We begin with postcompletion error (PCE) a type of systematic

  20. Aversive Olfactory Learning and Associative Long-Term Memory in "Caenorhabditis elegans"

    Amano, Hisayuki; Maruyama, Ichiro N.

    2011-01-01

    The nematode "Caenorhabditis elegans" ("C. elegans") adult hermaphrodite has 302 invariant neurons and is suited for cellular and molecular studies on complex behaviors including learning and memory. Here, we have developed protocols for classical conditioning of worms with 1-propanol, as a conditioned stimulus (CS), and hydrochloride (HCl) (pH…

  1. Food restriction increases long-term memory persistence in adult or aged mice.

    Talhati, F; Patti, C L; Zanin, K A; Lopes-Silva, L B; Ceccon, L M B; Hollais, A W; Bizerra, C S; Santos, R; Tufik, S; Frussa-Filho, R

    2014-04-03

    Food restriction (FR) seems to be the unique experimental manipulation that leads to a remarkable increase in lifespan in rodents. Evidences have suggested that FR can enhance memory in distinct animal models mainly during aging. However, only few studies systemically evaluated the effects FR on memory formation in both adult (3-month-old) and aged (18-24-month-old) mice. Thus, the aim of the present study was to investigate the effects of acute (12h) or repeated (12h/day for 2days) FR protocols on learning and memory of adult and aged mice evaluated in the plus-maze discriminative avoidance task (PM-DAT), an animal model that concurrently (but independently) evaluates learning and memory, anxiety and locomotion. We also investigated the possible role of FR-induced stress by the corticosterone concentration in adult mice. Male mice were kept at home cage with food ad libitum (CTRL-control condition) or subjected to FR during the dark phase of the cycle for 12h/day or 12h/2days. The FR protocols were applied before training, immediately after it or before testing. Our results demonstrated that only FR for 2days enhanced memory persistence when applied before training in adults and before testing in aged mice. Conversely, FR for 2days impaired consolidation and exerted no effects on retrieval irrespective of age. These effects do not seem to be related to corticosterone concentration. Collectively, these results indicate that FR for 2days can promote promnestic effects not only in aged mice but also in adults.

  2. An Adaptive Memory Model for Long-Term Navigation of Autonomous Mobile Robots

    M. Hentschel

    2011-01-01

    Full Text Available This paper introduces an environmental representation for autonomous mobile robots that continuously adapts over time. The presented approach is inspired by human memory information processing and stores the current as well as past knowledge of the environment. In this paper, the memory model is applied to time-variant information about obstacles and driveable routes in the workspace of the autonomous robot and used for solving the navigation cycle of the robot. This includes localization and path planning as well as vehicle control. The presented approach is evaluated in a real-world experiment within changing indoor environment. The results show that the environmental representation is stable, improves its quality over time, and adapts to changes.

  3. DAT genotype modulates striatal processing and long-term memory for items associated with reward and punishment.

    Wittmann, Bianca C; Tan, Geoffrey C; Lisman, John E; Dolan, Raymond J; Düzel, Emrah

    2013-09-01

    Previous studies have shown that appetitive motivation enhances episodic memory formation via a network including the substantia nigra/ventral tegmental area (SN/VTA), striatum and hippocampus. This functional magnetic resonance imaging (fMRI) study now contrasted the impact of aversive and appetitive motivation on episodic long-term memory. Cue pictures predicted monetary reward or punishment in alternating experimental blocks. One day later, episodic memory for the cue pictures was tested. We also investigated how the neural processing of appetitive and aversive motivation and episodic memory were modulated by dopaminergic mechanisms. To that end, participants were selected on the basis of their genotype for a variable number of tandem repeat polymorphism of the dopamine transporter (DAT) gene. The resulting groups were carefully matched for the 5-HTTLPR polymorphism of the serotonin transporter gene. Recognition memory for cues from both motivational categories was enhanced in participants homozygous for the 10-repeat allele of the DAT, the functional effects of which are not known yet, but not in heterozygous subjects. In comparison with heterozygous participants, 10-repeat homozygous participants also showed increased striatal activity for anticipation of motivational outcomes compared to neutral outcomes. In a subsequent memory analysis, encoding activity in striatum and hippocampus was found to be higher for later recognized items in 10-repeat homozygotes compared to 9/10-repeat heterozygotes. These findings suggest that processing of appetitive and aversive motivation in the human striatum involve the dopaminergic system and that dopamine plays a role in memory for both types of motivational information. In accordance with animal studies, these data support the idea that encoding of motivational events depends on dopaminergic processes in the hippocampus.

  4. Reprint of: DAT genotype modulates striatal processing and long-term memory for items associated with reward and punishment.

    Wittmann, Bianca C; Tan, Geoffrey C; Lisman, John E; Dolan, Raymond J; Düzel, Emrah

    2013-10-01

    Previous studies have shown that appetitive motivation enhances episodic memory formation via a network including the substantia nigra/ventral tegmental area (SN/VTA), striatum and hippocampus. This functional magnetic resonance imaging (fMRI) study now contrasted the impact of aversive and appetitive motivation on episodic long-term memory. Cue pictures predicted monetary reward or punishment in alternating experimental blocks. One day later, episodic memory for the cue pictures was tested. We also investigated how the neural processing of appetitive and aversive motivation and episodic memory were modulated by dopaminergic mechanisms. To that end, participants were selected on the basis of their genotype for a variable number of tandem repeat polymorphism of the dopamine transporter (DAT) gene. The resulting groups were carefully matched for the 5-HTTLPR polymorphism of the serotonin transporter gene. Recognition memory for cues from both motivational categories was enhanced in participants homozygous for the 10-repeat allele of the DAT, the functional effects of which are not known yet, but not in heterozygous subjects. In comparison with heterozygous participants, 10-repeat homozygous participants also showed increased striatal activity for anticipation of motivational outcomes compared to neutral outcomes. In a subsequent memory analysis, encoding activity in striatum and hippocampus was found to be higher for later recognized items in 10-repeat homozygotes compared to 9/10-repeat heterozygotes. These findings suggest that processing of appetitive and aversive motivation in the human striatum involve the dopaminergic system and that dopamine plays a role in memory for both types of motivational information. In accordance with animal studies, these data support the idea that encoding of motivational events depends on dopaminergic processes in the hippocampus.

  5. Working memory training is associated with long term attainments in math and reading comprehension

    Stina eSöderqvist; Sissela eBergman Nutley

    2015-01-01

    Training working memory (WM) using computerized programs has been shown to improve functions directly linked to WM such as following instructions and attention. These functions influence academic performance, which leads to the question of whether WM training can transfer to improved academic performance. We followed the academic performance of two age-matched groups during two years. As part of the curriculum in grade 4 (age 9-10), all students in one classroom (n = 20) completed Cogmed Work...

  6. Curcuma comosa improves learning and memory function on ovariectomized rats in a long-term Morris water maze test

    Su, Jian; Sripanidkulchai, Kittisak; Wyss, J. Michael; Sripanidkulchai, Bungorn

    2010-01-01

    Aim of the study Curcuma comosa extract and some purified compounds from this plant have been reported to have estrogenic-like effects, and estrogen improves learning in some animals and potentially in postmenopausal women; therefore, this study tested the hypothesis that Curcuma comosa and estrogen have similar beneficial effects on spatial learning and memory. Materials and methods Curcuma comosa hexane extract, containing 0.165 mg of (4E,6E)-1,7-diphenylhepta-4,6-dien-3-one per mg of the crude extract, was orally administered to ovariectomized Wistar rats at the doses of 250 or 500 mg/kg body weight. 17β-estradiol (10 μg/kg body weight, subcutaneously) was used as a positive control. Thirty days after the initiation of treatment, animals were tested in a Morris water maze for spatial learning and memory. They were re-tested every 30 days and a final probe trial was run on day 119. Results Compared to control rats, OVX rats displayed significant memory impairment for locating the platform in the water maze from day 67 after the surgery, onward. In contrast, OVX rats treated with either Curcuma comosa or estrogen were significantly protected from this decline in cognitive function. Further, the protection of cognitive effects by Curcuma comosa was larger at higher dose. Conclusions These results suggest that long-term treatment with Curcuma comosa has beneficial effects on learning and memory function in rats. PMID:20420894

  7. Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera).

    Burden, Christina M; Elmore, Christopher; Hladun, Kristen R; Trumble, John T; Smith, Brian H

    2016-05-01

    A plethora of toxic compounds - including pesticides, heavy metals, and metalloids - have been detected in honey bees (Apis mellifera) and their colonies. One such compound is selenium, which bees are exposed to by consuming nectar and pollen from flowers grown in contaminated areas. Though selenium is lethal at high concentrations, sublethal exposure may also impair honey bees' ability to function normally. Examining the effect of selenium exposure on learning and memory provides a sensitive assay with which to identify sublethal effects on honey bee health and behavior. To determine whether sublethal selenium exposure causes learning and memory deficits, we used proboscis extension reflex conditioning coupled with recall tests 30min and 24h post-conditioning. We exposed forager honey bees to a single sublethal dose of selenium, and 3h later we used an olfactory conditioning assay to train the bees to discriminate between one odor associated with sucrose-reinforcement and a second unreinforced odor. Following conditioning we tested short- and long-term recall of the task. Acute exposure to as little as 1.8ng of an inorganic form of selenium (sodium selenate) before conditioning caused a reduction in behavioral performance during conditioning. And, exposure to 18ng of either an inorganic form (sodium selenate) or an organic form (methylseleno-l-cysteine) of selenium caused a reduction in the bees' performance during the long-term recall test. These concentrations of selenium are lower than those found in the nectar of plants grown in selenium-contaminated soil, indicating that even low-grade selenium toxicity produces significant learning and memory impairments. This may reduce foragers' ability to effectively gather resources for the colony or nurse bees' ability to care for and maintain a healthy colony.

  8. Delayed wave of c-Fos expression in the dorsal hippocampus involved specifically in persistence of long-term memory storage.

    Katche, Cynthia; Bekinschtein, Pedro; Slipczuk, Leandro; Goldin, Andrea; Izquierdo, Ivan A; Cammarota, Martin; Medina, Jorge H

    2010-01-05

    Memory formation is a temporally graded process during which transcription and translation steps are required in the first hours after acquisition. Although persistence is a key characteristic of memory storage, its mechanisms are scarcely characterized. Here, we show that long-lasting but not short-lived inhibitory avoidance long-term memory is associated with a delayed expression of c-Fos in the hippocampus. Importantly, this late wave of c-Fos is necessary for maintenance of inhibitory avoidance long-term storage. Moreover, inhibition of transcription in the dorsal hippocampus 24 h after training hinders persistence but not formation of long-term storage. These findings indicate that a delayed phase of transcription is essential for maintenance of a hippocampus-dependent memory trace. Our results support the hypothesis that recurrent rounds of consolidation-like events take place late after learning in the dorsal hippocampus to maintain memories.

  9. Long-term avoidance memory formation is associated with a transient increase in mushroom body synaptic complexes in leaf-cutting ants

    Agustina eFalibene

    2015-04-01

    Full Text Available Long-term behavioral changes related to learning and experience have been shown to be associated with structural remodeling in the brain. Leaf-cutting ants learn to avoid previously preferred plants after they have proved harmful for their symbiotic fungus, a process that involves long-term olfactory memory. We studied the dynamics of brain microarchitectural changes after long-term olfactory memory formation following avoidance learning in Acromyrmex ambiguus. After performing experiments to control for possible neuronal changes related to age and body size, we quantified synaptic complexes (microglomeruli, MG in olfactory regions of the mushroom bodies (MB at different times after learning. Long-term avoidance memory formation was associated with a transient change in MG densities. Two days after learning, MG density was higher than before learning. At days 4 and 15 after learning — when ants still showed plant avoidance — MG densities had decreased to the initial state. The structural reorganization of MG triggered by long-term avoidance memory formation clearly differed from changes promoted by pure exposure to and collection of novel plants with distinct odors. Sensory exposure by the simultaneous collection of several, instead of one, non-harmful plant species resulted in a decrease in MG densities in the olfactory lip. We hypothesize that while sensory exposure leads to MG pruning in the MB olfactory lip, the formation of long-term avoidance memory involves an initial growth of new MG followed by subsequent pruning.

  10. Effect of general anesthesia in infancy on long-term recognition memory in humans and rats.

    Stratmann, Greg; Lee, Joshua; Sall, Jeffrey W; Lee, Bradley H; Alvi, Rehan S; Shih, Jennifer; Rowe, Allison M; Ramage, Tatiana M; Chang, Flora L; Alexander, Terri G; Lempert, David K; Lin, Nan; Siu, Kasey H; Elphick, Sophie A; Wong, Alice; Schnair, Caitlin I; Vu, Alexander F; Chan, John T; Zai, Huizhen; Wong, Michelle K; Anthony, Amanda M; Barbour, Kyle C; Ben-Tzur, Dana; Kazarian, Natalie E; Lee, Joyce Y Y; Shen, Jay R; Liu, Eric; Behniwal, Gurbir S; Lammers, Cathy R; Quinones, Zoel; Aggarwal, Anuj; Cedars, Elizabeth; Yonelinas, Andrew P; Ghetti, Simona

    2014-09-01

    Anesthesia in infancy impairs performance in recognition memory tasks in mammalian animals, but it is unknown if this occurs in humans. Successful recognition can be based on stimulus familiarity or recollection of event details. Several brain structures involved in recollection are affected by anesthesia-induced neurodegeneration in animals. Therefore, we hypothesized that anesthesia in infancy impairs recollection later in life in humans and rats. Twenty eight children ages 6-11 who had undergone a procedure requiring general anesthesia before age 1 were compared with 28 age- and gender-matched children who had not undergone anesthesia. Recollection and familiarity were assessed in an object recognition memory test using receiver operator characteristic analysis. In addition, IQ and Child Behavior Checklist scores were assessed. In parallel, thirty three 7-day-old rats were randomized to receive anesthesia or sham anesthesia. Over 10 months, recollection and familiarity were assessed using an odor recognition test. We found that anesthetized children had significantly lower recollection scores and were impaired at recollecting associative information compared with controls. Familiarity, IQ, and Child Behavior Checklist scores were not different between groups. In rats, anesthetized subjects had significantly lower recollection scores than controls while familiarity was unaffected. Rats that had undergone tissue injury during anesthesia had similar recollection indices as rats that had been anesthetized without tissue injury. These findings suggest that general anesthesia in infancy impairs recollection later in life in humans and rats. In rats, this effect is independent of underlying disease or tissue injury.

  11. Interaction between mode of learning and subjective experience: translation effects in long-term memory.

    Rackie, James M; Brandt, Karen R; Eysenck, Michael W

    2015-01-01

    It has been suggested that writing auditorily presented words at encoding involves distinctive translation processes between visual and auditory domains, leading to the formation of distinctive memory traces at retrieval. This translation effect leads to higher levels of recognition than the writing of visually presented words, a non-translation effect. The present research investigated whether writing and the other translation effect of vocalisation (vocalising visually presented words) would be present in tests of recall, recognition memory and whether these effects are based on the subjective experience of remembering or knowing. Experiment 1 found a translation effect in the auditory domain in recall, as the translation effect of writing yielded higher recall than both non-translation effects of vocalisation and silently hearing. Experiment 2 found a translation effect in the visual domain in recognition, as the translation effect of vocalisation yielded higher recognition than both non-translation effects of writing and silently reading. This translation effect was attributable to the subjective experience of remembering rather than knowing. The present research therefore demonstrates the beneficial effect of translation in both recall and recognition, with the effect of vocalisation in recognition being based on rich episodic remembering.

  12. Anodal tDCS over the Primary Motor Cortex Facilitates Long-Term Memory Formation Reflecting Use-Dependent Plasticity.

    Orjon Rroji

    Full Text Available Previous research suggests that anodal transcranial direct current stimulation (tDCS over the primary motor cortex (M1 modulates NMDA receptor dependent processes that mediate synaptic plasticity. Here we test this proposal by applying anodal versus sham tDCS while subjects practiced to flex the thumb as fast as possible (ballistic movements. Repetitive practice of this task has been shown to result in performance improvements that reflect use-dependent plasticity resulting from NMDA receptor mediated, long-term potentiation (LTP-like processes. Using a double-blind within-subject cross-over design, subjects (n=14 participated either in an anodal or a sham tDCS session which were at least 3 months apart. Sham or anodal tDCS (1 mA was applied for 20 min during motor practice and retention was tested 30 min, 24 hours and one week later. All subjects improved performance during each of the two sessions (p < 0.001 and learning gains were similar. Our main result is that long term retention performance (i.e. 1 week after practice was significantly better when practice was performed with anodal tDCS than with sham tDCS (p < 0.001. This effect was large (Cohen's d=1.01 and all but one subject followed the group trend. Our data strongly suggest that anodal tDCS facilitates long-term memory formation reflecting use-dependent plasticity. Our results support the notion that anodal tDCS facilitates synaptic plasticity mediated by an LTP-like mechanism, which is in accordance with previous research.

  13. Historical review of long-term soil sampling for environmental surveillance at the Hanford Site and vicinity

    Price, K.R.; Rickard, W.H.

    1997-08-01

    Soil samples have been collected routinely from the environs of the Hanford Site and analyzed since 1971. Correct interpretation of results depends on samples being collected from the same locations, the locations remaining relatively undisturbed, and collection and analytical procedures remaining the same or being equivalent. Historical files, documents, and annual environmental reports were reviewed to evaluate these factors. It was determined that 20 soil sampling locations, 11 onsite and 9 offsite, were established between 1971 and 1977 and represent long-term sampling locations. Sample collection and analytical procedures have remained essentially the same since 1971. The physical ecological attributes of each long-term soil sampling location were evaluated. During the review of historical records, a few results for 1970, 1971, and 1972 were noted as previously unreported in annual or special reports. These results are included in Appendix A. To complete the record, results previously reported in annual environmental reports are given in Appendix B. Global Positioning System (GPS) reading for 20 long-term soil sampling locations are provided in Appendix C.

  14. Combined Liposuction and Excision of Lipomas: Long-Term Evaluation of a Large Sample of Patients

    Libby R. Copeland-Halperin

    2015-01-01

    Full Text Available Background. Lipomas are benign tumors of mature fat cells. They can be removed by liposuction, yet this technique is seldom employed because of concerns that removal may be incomplete and recurrence may be more frequent than after conventional excision. Objectives. We assessed the short- and long-term clinical outcomes and recurrence of combined liposuction and limited surgical excision of subcutaneous lipomas. Methods. From 2003 to 2012, 25 patients with 48 lipomas were treated with liposuction followed by direct excision through the same incision to remove residual lipomatous tissue. Initial postoperative follow-up ranged from 1 week to 3 months, and long-term outcomes, complications, and recurrence were surveyed 1 to 10 years postoperatively. Results. Lipomas on the head, neck, trunk, and extremities ranged from 1 to 15 cm in diameter. Early postoperative hematoma and seromas were managed by aspiration. Among 23 survey respondents (92%, patients were uniformly pleased with the cosmetic results; none reported recurrent lipoma. Conclusions. The combination of liposuction and excision is a safe alternative for lipoma removal; malignancy and recurrence are uncommon. Liposuction performed through a small incision provides satisfactory aesthetic results in most cases. Once reduced in size, residual lipomatous and capsular tissue can be removed without expanding the incision. These favorable outcomes support wider application of this technique in appropriate cases.

  15. Working memory training is associated with long term attainments in math and reading comprehension

    Stina eSöderqvist

    2015-11-01

    Full Text Available Training working memory (WM using computerized programs has been shown to improve functions directly linked to WM such as following instructions and attention. These functions influence academic performance, which leads to the question of whether WM training can transfer to improved academic performance. We followed the academic performance of two age-matched groups during two years. As part of the curriculum in grade 4 (age 9-10, all students in one classroom (n = 20 completed Cogmed Working Memory Training (CWMT whereas children in the other classroom (n = 22 received education as usual. Performance on nationally standardized tests in math and reading comprehension was used as outcome measures at baseline and two years later. At baseline both classes were normal/high performing according to national standards. At grade 6, reading comprehension had improved to a significantly greater extent for the training group compared to the control group (medium effect size, Cohen’s d = 0.66, p = 0.045. For math performance the same pattern was observed with a medium effect size (Cohen’s d = 0.58 reaching statistical trend levels (p = 0.091. Moreover, the academic attainments were found to correlate with the degree of improvements during training (p-values 1 year effects of WM training on academic performance. We found performance on both reading and math to be positively impacted after completion of CWMT. Since there were no baseline differences between the groups, the results may reflect an influence on learning capacity, with improved WM leading to a boost in students’ capacity to learn. This study is also the first to investigate the effects of CWMT on academic performance in typical or high achieving students. The results suggest that WM training can help optimize the academic potential of high performers.

  16. Working Memory Training is Associated with Long Term Attainments in Math and Reading.

    Söderqvist, Stina; Bergman Nutley, Sissela

    2015-01-01

    Training working memory (WM) using computerized programs has been shown to improve functions directly linked to WM such as following instructions and attention. These functions influence academic performance, which leads to the question of whether WM training can transfer to improved academic performance. We followed the academic performance of two age-matched groups during 2 years. As part of the curriculum in grade 4 (age 9-10), all students in one classroom (n = 20) completed Cogmed Working Memory Training (CWMT) whereas children in the other classroom (n = 22) received education as usual. Performance on nationally standardized tests in math and reading was used as outcome measures at baseline and two years later. At baseline both classes were normal/high performing according to national standards. At grade 6, reading had improved to a significantly greater extent for the training group compared to the control group (medium effect size, Cohen's d = 0.66, p = 0.045). For math performance the same pattern was observed with a medium effect size (Cohen's d = 0.58) reaching statistical trend levels (p = 0.091). Moreover, the academic attainments were found to correlate with the degree of improvements during training (p 1 year) effects of WM training on academic performance. We found performance on both reading and math to be positively impacted after completion of CWMT. Since there were no baseline differences between the groups, the results may reflect an influence on learning capacity, with improved WM leading to a boost in students' capacity to learn. This study is also the first to investigate the effects of CWMT on academic performance in typical or high achieving students. The results suggest that WM training can help optimize the academic potential of high performers.

  17. Activation of the basolateral amygdala induces long-term enhancement of specific memory representations in the cerebral cortex.

    Chavez, Candice M; McGaugh, James L; Weinberger, Norman M

    2013-03-01

    The basolateral amygdala (BLA) modulates memory, particularly for arousing or emotional events, during post-training periods of consolidation. It strengthens memories whose substrates in part or whole are stored remotely, in structures such as the hippocampus, striatum and cerebral cortex. However, the mechanisms by which the BLA influences distant memory traces are unknown, largely because of the need for identifiable target mnemonic representations. Associative tuning plasticity in the primary auditory cortex (A1) constitutes a well-characterized candidate specific memory substrate that is ubiquitous across species, tasks and motivational states. When tone predicts reinforcement, the tuning of cells in A1 shifts toward or to the signal frequency within its tonotopic map, producing an over-representation of behaviorally important sounds. Tuning shifts have the cardinal attributes of forms of memory, including associativity, specificity, rapid induction, consolidation and long-term retention and are therefore likely memory representations. We hypothesized that the BLA strengthens memories by increasing their cortical representations. We recorded multiple unit activity from A1 of rats that received a single discrimination training session in which two tones (2.0 s) separated by 1.25 octaves were either paired with brief electrical stimulation (400 ms) of the BLA (CS+) or not (CS-). Frequency response areas generated by presenting a matrix of test tones (0.5-53.82 kHz, 0-70 dB) were obtained before training and daily for 3 weeks post-training. Tuning both at threshold and above threshold shifted predominantly toward the CS+ beginning on day 1. Tuning shifts were maintained for the entire 3 weeks. Absolute threshold and bandwidth decreased, producing less enduring increases in sensitivity and selectivity. BLA-induced tuning shifts were associative, highly specific and long-lasting. We propose that the BLA strengthens memory for important experiences by increasing the

  18. Long-term effect of early-life stress from earthquake exposure on working memory in adulthood

    Li N

    2015-11-01

    Full Text Available Na Li,1-3* Yumei Wang,1-3* Xiaochuan Zhao,1-3 Yuanyuan Gao,1-3 Mei Song,1-3 Lulu Yu,1-3 Lan Wang,1-3 Ning Li,1-3 Qianqian Chen,1-3 Yunpeng Li,1-3 Jiajia Cai,1-3 Xueyi Wang1-31Department of Psychiatry, The First Hospital of Hebei Medical University, 2Mental Health Institute of Hebei Medical University, 3Brain Ageing and Cognitive Neuroscience Laboratory, Hebei, People’s Republic of China *These authors contributed equally to this work Objective: The present study aimed to investigate the long-term effect of 1976 Tangshan earthquake exposure in early life on performance of working memory in adulthood.Methods: A total of 907 study subjects born and raised in Tangshan were enrolled in this study. They were divided into three groups according to the dates of birth: infant exposure (3–12 months, n=274, prenatal exposure (n=269, and no exposure (born at least 1 year after the earthquake, n=364. The prenatal group was further divided into first, second, and third trimester subgroups based on the timing of exposure during pregnancy. Hopkins Verbal Learning Test-Revised and Brief Visuospatial Memory Test-Revised (BVMT-R were used to measure the performance of working memory. Unconditional logistic regression analysis was used to analyze the influential factors for impaired working memory.Results: The Hopkins Verbal Learning Test-Revised scores did not show significant difference across the three groups. Compared with no exposure group, the BVMT-R scores were slightly lower in the prenatal exposure group and markedly decreased in the infant exposure group. When the BVMT-R scores were analyzed in three subgroups, the results showed that the subjects whose mothers were exposed to earthquake in the second and third trimesters of pregnancy had significantly lower BVMT-R scores compared with those in the first trimester. Education level and early-life earthquake exposure were identified as independent risk factors for reduced performance of

  19. Impaired long-term memory retention and working memory in sdy mutant mice with a deletion in Dtnbp1, a susceptibility gene for schizophrenia

    Takao Keizo

    2008-10-01

    Full Text Available Abstract Background Schizophrenia is a complex genetic disorder caused by multiple genetic and environmental factors. The dystrobrevin-binding protein 1 (DTNBP1: dysbindin-1 gene is a major susceptibility gene for schizophrenia. Genetic variations in DTNBP1 are associated with cognitive functions, general cognitive ability and memory function, and clinical features of patients with schizophrenia including negative symptoms and cognitive decline. Since reduced expression of dysbindin-1 has been observed in postmortem brains of patients with schizophrenia, the sandy (sdy mouse, which has a deletion in the Dtnbp1 gene and expresses no dysbindin-1 protein, could be an animal model of schizophrenia. To address this issue, we have carried out a comprehensive behavioral analysis of the sdy mouse in this study. Results In a rotarod test, sdy mice did not exhibit motor learning whilst the wild type mice did. In a Barnes circular maze test both sdy mice and wild type mice learned to selectively locate the escape hole during the course of the training period and in the probe trial conducted 24 hours after last training. However, sdy mice did not locate the correct hole in the retention probe tests 7 days after the last training trial, whereas wild type mice did, indicating impaired long-term memory retention. A T-maze forced alternation task, a task of working memory, revealed no effect of training in sdy mice despite the obvious effect of training in wild type mice, suggesting a working memory deficit. Conclusion Sdy mouse showed impaired long-term memory retention and working memory. Since genetic variation in DTNBP1 is associated with both schizophrenia and memory function, and memory function is compromised in patients with schizophrenia, the sdy mouse may represent a useful animal model to investigate the mechanisms of memory dysfunction in the disorder.

  20. Comparison the Effect of Zinc Oxide and Magnesium Oxide Nano Particles on Long Term Memory in Adult Male Mice

    Mahnaz Kesmati

    2016-08-01

    Full Text Available Background Magnesium (Mg and zinc (Zn are two essential elemnts for normal performance of central nervous system. So that the learning and memory are influenced by these ions that antagonized NMDA (N methyl-D-aspartate receptor. Objectives This study was conducted to evaluate the effect of nanoparticles of zinc oxide (ZnO and magnesium oxide (MgO on passive avoidance memory in mice. Methods In this experimental study adult male NMRI mice weighing 25 ± 3g were used. ZnO and MgO nano particles (1, 2.5 and 5 mg/kg, intrapretoneally (i.p. were injected pre-training in model of passive avoidance learning. Memory was evaluated at 1, 3 and 7 days after training. Delay time in coming down from the safe platform in step down apparatus was evaluated as an index of memory. Open field test was used for evaluation the locomotor activity. Results Nano MgO 2.5 and 5 mg/kg increased delay time in coming down from plateform at one day after training (P < 0.05 in dose dependent manner. Nano ZnO 2.5 and 5 mg/kg reduced delay time in coming down from the platform 1, 3 and 7 day after training (P < 0.05 and just 3 days after training (P < 0.05 respectivley. Locomotor activity did not change in presence of MgO and/or ZnO nano particles. Conclusions It seems that various effects of nano ZnO and MgO on long term memeory is related to the different effects of Zn and Mg ions on receptors (such as NMDA involved in memory process. Toxicity and/ or preservation of nanoparticle in body are another possible reasons.

  1. Participation of the classical speech areas in auditory long-term memory.

    Anke Ninija Karabanov

    Full Text Available Accumulating evidence suggests that storing speech sounds requires transposing rapidly fluctuating sound waves into more easily encoded oromotor sequences. If so, then the classical speech areas in the caudalmost portion of the temporal gyrus (pSTG and in the inferior frontal gyrus (IFG may be critical for performing this acoustic-oromotor transposition. We tested this proposal by applying repetitive transcranial magnetic stimulation (rTMS to each of these left-hemisphere loci, as well as to a nonspeech locus, while participants listened to pseudowords. After 5 minutes these stimuli were re-presented together with new ones in a recognition test. Compared to control-site stimulation, pSTG stimulation produced a highly significant increase in recognition error rate, without affecting reaction time. By contrast, IFG stimulation led only to a weak, non-significant, trend toward recognition memory impairment. Importantly, the impairment after pSTG stimulation was not due to interference with perception, since the same stimulation failed to affect pseudoword discrimination examined with short interstimulus intervals. Our findings suggest that pSTG is essential for transforming speech sounds into stored motor plans for reproducing the sound. Whether or not the IFG also plays a role in speech-sound recognition could not be determined from the present results.

  2. Long-term potentiation in bone – a role for glutamate in strain-induced cellular memory?

    Genever Paul G

    2003-07-01

    Full Text Available Abstract Background The adaptive response of bone cells to mechanical strain is a primary determinant of skeletal architecture and bone mass. In vivo mechanical loading induces new bone formation and increases bone mineral density whereas disuse, immobilisation and weightlessness induce bone loss. The potency of mechanical strain is such that a single brief period of loading at physiological strain magnitude is able to induce a long-lasting osteogenic response that lasts for days. Although the process of mechanotransduction in bone is incompletely understood, observations that responses to mechanical strain outlast the duration of stimulation necessitate the existence of a form of cellular memory through which transient strain episodes are recorded, interpreted and remembered by bone cells. Recent evidence supports the existence of a complex multicellular glutamate-signalling network in bone that shares functional similarities to glutamatergic neurotransmission in the central nervous system. In neurones, these signalling molecules coordinate synaptic communication required to support learning and memory formation, through a complex process of long-term potentiation. Presentation of the hypothesis We hypothesise that osteoblasts use a cellular mechanism similar or identical to neuronal long-term potentiation in the central nervous system to mediate long-lasting changes in osteogenesis following brief periods of mechanical strain. Testing the hypothesis N-methyl-D-aspartate (NMDA receptor antagonism should inhibit the saturating response of mechanical strain and reduce the enhanced osteogenicity of segregated loading to that of an equivalent period of uninterrupted loading. Changes in α-amino-3-hydroxy-5-methyl-isoxazole propionate (AMPA receptor expression, localisation and electrophysiological responses should be induced by mechanical strain and inhibited by modulators of neuronal long-term potentiation. Implications of the hypothesis If true

  3. How Chunks, Long-Term Working Memory and Templates Offer a Cognitive Explanation for Neuroimaging Data on Expertise Acquisition: A Two-Stage Framework

    Guida, Alessandro; Gobet, Fernand; Tardieu, Hubert; Nicolas, Serge

    2012-01-01

    Our review of research on PET and fMRI neuroimaging of experts and expertise acquisition reveals two apparently discordant patterns in working-memory-related tasks. When experts are involved, studies show activations in brain regions typically activated during long-term memory tasks that are not observed with novices, a result that is compatible…

  4. The Effects of Changing Attention and Context in an Awake Offline Processing Period on Visual Long-Term Memory

    Timothy Michael Ellmore

    2016-01-01

    Full Text Available There is accumulating evidence that sleep as well as awake offline processing is important for the transformation of new experiences into long-term memory. Yet much remains to be understood about how various cognitive factors influence the efficiency of awake offline processing. In the present study we investigated how changes in attention and context in the immediate period after exposure to new visual information influences long-term memory consolidation. After presentation of multiple naturalistic scenes within a working memory paradigm, recognition was assessed 30 minutes and 24 hours later in three groups of subjects. One group of subjects engaged in a focused attention task (the Revised Attentional Network Task (R-ANT in the 30 minutes after exposure to the scenes. Another group of subjects remained in the testing room during the 30 minutes after scene exposure and engaged in no goal- or task-directed activities. A third group of subjects left the testing room and returned 30 minutes later. A signal detection analysis revealed no significant differences among the three groups in hits, false alarms, or sensitivity on the 30-minute recognition task. At the 24-hour recognition test, the group that performed the R-ANT made significantly fewer hits compared to the group that left the testing room and didn’t perform the attention ask. The group that performed the R-ANT and the group that remained in the testing room during the 30-minute post-exposure interval made significantly fewer false alarms on the 24-hour recognition test compared to the group that left the testing room. The group that stayed in the testing room and engaged in no goal- or task-directed activities exhibited significantly higher sensitivity (d’ compared to the group that left the testing room and the group that performed the R-ANT task. Staying in the same context after exposure to new information and resting quietly with minimal engagement of attention results in the

  5. Hearing Loss Is Negatively Related to Episodic and Semantic Long-Term Memory but Not to Short-Term Memory

    Ronnberg, Jerker; Danielsson, Henrik; Rudner, Mary; Arlinger, Stig; Sternang, Ola; Wahlin, Ake; Nilsson, Lars-Goran

    2011-01-01

    Purpose: To test the relationship between degree of hearing loss and different memory systems in hearing aid users. Method: Structural equation modeling (SEM) was used to study the relationship between auditory and visual acuity and different cognitive and memory functions in an age-hetereogenous subsample of 160 hearing aid users without…

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

    Eisenhardt, Dorothea

    2014-01-01

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

  7. Unconventional cytokine profiles and development of T cell memory in long-term survivors after cancer vaccination

    Kyte, Jon Amund; Trachsel, Sissel; Risberg, Bente

    2009-01-01

    Cancer vaccine trials frequently report on immunological responses, without any clinical benefit. This paradox may reflect the challenge of discriminating between effective and pointless immune responses and sparse knowledge on their long-term development. Here, we have analyzed T cell responses......-delineation applies to cancer vaccine responses. T cell clones were generated from all nine patients studied. We find that surviving patients harbor durable tumor-specific responses against vaccine antigens from telomerase, RAS or TGFbeta receptor II. Analyses of consecutive samples suggest that booster...

  8. D-cycloserine prevents relational memory deficits and suppression of long-term potentiation induced by scopolamine in the hippocampus.

    Portero-Tresserra, Marta; Del Olmo, Nuria; Martí-Nicolovius, Margarita; Guillazo-Blanch, Gemma; Vale-Martínez, Anna

    2014-11-01

    Previous research has demonstrated that systemic D-cycloserine (DCS), a partial agonist of the N-methyl-D-aspartate receptor (NMDAR), enhances memory processes in different learning paradigms and attenuates mnemonic deficits produced by diverse pharmacological manipulations. In the present study two experiments were conducted in rats to investigate whether DCS administered in the hippocampus may rescue relational memory deficits and improve deficient synaptic plasticity, both induced by an intracerebral injection of the muscarinic receptor antagonist scopolamine (SCOP). In experiment 1, we assessed whether DCS would prevent SCOP-induced amnesia in an olfactory learning paradigm requiring the integrity of the cholinergic system, the social transmission of food preference (STFP). The results showed that DCS (10 μg/site) injected into the ventral hippocampus (vHPC) before STFP acquisition compensated the 24-h retention deficit elicited by post-training intra-vHPC SCOP (40 μg/site), although it did not affect memory expression in non-SCOP treated rats. In experiment 2, we evaluated whether the perfusion of DCS in hippocampal slices may potentiate synaptic plasticity in CA1 synapses and thus recover SCOP-induced deficits in long-term potentiation (LTP). We found that DCS (50 µM and 100 µM) was able to rescue SCOP (100 µM)-induced LTP maintenance impairment, in agreement with the behavioral findings. Additionally, DCS alone (50 µM and 100 µM) enhanced field excitatory postsynaptic potentials prior to high frequency stimulation, although it did not significantly potentiate LTP. Our results suggest that positive modulation of the NMDAR, by activation of the glycine-binding site, may compensate relational memory impairments due to hippocampal muscarinic neurotransmission dysfunction possibly through enhancements in LTP maintenance.

  9. Intensification of long-term memory deficit by chronic stress and prevention by nicotine in a rat model of Alzheimer's disease.

    Alkadhi, Karim A; Srivareerat, Marisa; Tran, Trinh T

    2010-11-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cholinergic dysfunction and deposition of beta-amyloid (Aβ) in regions of the brain associated with learning and memory. The sporadic nature and late onset of most AD cases suggests that aside from biological determinants, environmental factors such as stress may also play a role in the progression of the disease. Behavioral and molecular studies were utilized to evaluate the effects of chronic nicotine treatment in the prevention of impairment of long-term memory. The rat model of AD was induced by i.c.v. osmotic pump infusion of Aβ peptides. Chronic psychosocial stress and chronic nicotine treatment were instituted for 6weeks. Spatial memory testing in the Radial Arm Water Maze revealed that, although stress, by itself, did not affect long-term memory, the combination of chronic stress and Aβ infusion impaired long-term memory significantly more than Aβ peptides infusion alone. Chronic nicotine treatment completely prevented Aβ- and stress/Aβ combination-induced memory impairment. Furthermore, molecular findings in hippocampal CA1 region of stress/Aβ rats indicated marked reduction in the protein levels of phosphorylated cAMP response element binding (p-CREB) and calcium-calmodulin-dependent protein kinase IV (CaMKIV), with significant increases in the levels of brain-derived neurotrophic factor (BDNF). These disturbances in signaling pathways, which may be the underlying mechanisms of impairment of long-term memory in these rats, were totally prevented by chronic nicotine treatment.

  10. Memory of childhood trauma before and after long-term psychological treatment of borderline personality disorder.

    Kremers, I P; Van Giezen, A E; Van der Does, A J W; Van Dyck, R; Spinhoven, Ph

    2007-03-01

    The present study investigated the consistency of self-reports of childhood traumatic events in a sample of 50 patients with a borderline personality disorder (BPD) before and after 27 months of intensive treatment with schema focused therapy or transference focused psychotherapy. The mean number of reported sexual, physical and emotional traumatic events did not change following treatment. Test-retest correlations of the trauma-interview also indicated high stability of the total number of sexual, physical and emotional events reported. The majority of the patients, however, did no longer report at least one of the 33 listed events after psychotherapy, and the majority reported at least one event that they had not mentioned before the start of treatment. These findings were not related to type of treatment or changes in suppression, intrusions, avoidance of intrusions, dissociative symptoms, depressive symptoms, and borderline symptoms.

  11. Effects of long-term voluntary exercise on learning and memory processes: dependency of the task and level of exercise.

    García-Capdevila, Sílvia; Portell-Cortés, Isabel; Torras-Garcia, Meritxell; Coll-Andreu, Margalida; Costa-Miserachs, David

    2009-09-14

    The effect of long-term voluntary exercise (running wheel) on anxiety-like behaviour (plus maze and open field) and learning and memory processes (object recognition and two-way active avoidance) was examined on Wistar rats. Because major individual differences in running wheel behaviour were observed, the data were analysed considering the exercising animals both as a whole and grouped according to the time spent in the running wheel (low, high, and very-high running). Although some variables related to anxiety-like behaviour seem to reflect an anxiogenic compatible effect, the view of the complete set of variables could be interpreted as an enhancement of defensive and risk assessment behaviours in exercised animals, without major differences depending on the exercise level. Effects on learning and memory processes were dependent on task and level of exercise. Two-way avoidance was not affected either in the acquisition or in the retention session, while the retention of object recognition task was affected. In this latter task, an enhancement in low running subjects and impairment in high and very-high running animals were observed.

  12. Working Memory Training for Healthy Older Adults: The Role of Individual Characteristics in Explaining Short- and Long-Term Gains

    Borella, Erika; Carbone, Elena; Pastore, Massimiliano; De Beni, Rossana; Carretti, Barbara

    2017-01-01

    Objective: The aim of the present study was to explore whether individual characteristics such as age, education, vocabulary, and baseline performance in a working memory (WM) task—similar to the one used in the training (criterion task)—predict the short- and long-term specific gains and transfer effects of a verbal WM training for older adults. Method: Four studies that adopted the Borella et al. (2010) verbal WM training procedure were found eligible for our analysis as they included: healthy older adults who attended either the training sessions (WM training group), or alternative activities (active control group); the same measures for assessing specific gains (on the criterion WM task), and transfer effects (nearest on a visuo-spatial WM task, near on short-term memory tasks and far on a measure of fluid intelligence, a measure of processing speed and two inhibitory measures); and a follow-up session. Results: Linear mixed models confirmed the overall efficacy of the training, in the short-term at least, and some maintenance effects. In the trained group, the individual characteristics considered were found to contribute (albeit only modestly in some cases) to explaining the effects of the training. Conclusions: Overall, our findings suggest the importance of taking individual characteristics and individual differences into account when examining WM training gains in older adults.

  13. The effects of cortisol increase on long-term memory retrieval during and after acute psychosocial stress.

    Tollenaar, Marieke S; Elzinga, Bernet M; Spinhoven, Philip; Everaerd, Walter A M

    2008-03-01

    In this study the effects of stress-induced cortisol increases on long-term memory retrieval during and after acute psychosocial stress were examined. Seventy male students were exposed to either a psychosocial stress task or to a non-stressful control task. During and after this task, retrieval was tested for idiosyncratic emotionally negative and neutral word pair associations that were learned 1 day or 5 weeks earlier. Within the stress condition, retrieval of negative words, 5 weeks after learning, was impaired both during and after the stress task compared to the control group. Further, during the stress task, when sympathetic activity was enhanced, impaired retrieval of both neutral and emotional words was significantly related to enhanced cortisol response. In contrast, after the stress task, when cortisol levels were still increased but sympathetic activity was low again, no association was found between cortisol increase and retrieval of either neutral or emotional material. These results are in line with the previous animal research showing that when arousal is high, cortisol increase can impair memory retrieval.

  14. Long-term spatial memory and morphological changes in hippocampus of Wistar rats exposed to smoke from Carica papaya leaves

    Aboyeji Lukuman Oyewole; Bamidele Victor Owoyele

    2014-01-01

    Objective:To investigate the effects of smoking of dried leaves of Carica papaya (pawpaw) based on ethnopharmacological information which indicated that smoking of papaya leaves could influence motor performance and learning. Methods:Twenty-four rats were used for the study, and were grouped into four groups. Groups 1 served as the control (not exposed to papaya leaves smoke), while Groups 2, 3 and 4 were exposed to smoke from 6.25 g, 12.50 g and 18.75 g of dry pawpaw leaves respectively in a smoking chamber twice daily for 21 d with each exposure lasting for 3 min. Lastly, hippocampus was harvested in each group for histological study. Results: The results showed that there were significant (P Conclusions: In conclusion, the findings from this study has demonstrated that smoking of papaya leaves has the ability to maintain an intact long-term spatial memory at all doses but retrieving such memory is faster with the low and medium dosages.

  15. Learning to never forget – Time scales and specificity of long-term memory of a motor skill

    Se-Woong ePark

    2013-09-01

    Full Text Available Despite anecdotal reports that humans retain acquired motor skills for many years, if not a lifetime, long-term memory of motor skills has received little attention. While numerous neuroimaging studies showed practice-induced cortical plasticity, the behavioral correlates, what is retained and also what is forgotten, are little understood. This longitudinal case study on four subjects presents detailed kinematic analyses of humans practicing a bimanual polyrhythmic task over 2 months with retention tests after 6 months and, for two subjects, after 8 years. Results showed that individuals not only retained the task, but also reproduced their individual style of performance, even after 8 years. During practice, variables such as the two hands’ frequency ratio and relative phase changed at different rates, indicative of multiple time-scales of neural processes. Frequency leakage across hands, reflecting inter manual crosstalk, attenuated at a significantly slower rate and was the only variable not maintained after 8 years. Complementing recent findings on neuroplasticity in grey and white matter, our study presents new behavioral evidence that highlights the multi-scale process of practice-induced changes and its remarkable persistence. Results suggest that motor memory may comprise not only higher-level task achievement but also individual kinematic signatures.

  16. Integration of Metagenomic and Biogeochemical Data from Soils Sampled from a Long-Term Reciprocal Transplant

    Bailey, V. L.; Hess, N. J.; McCue, L. A.

    2014-12-01

    The long-term impacts of climate conditions on soil ecosystems are difficult to discern with sufficient resolution to underpin a predictive understanding of ecosystem response to global climate change. The structure and function of the microbial community is intimately linked to soil organic carbon (SOC) by both the deposition of new carbon, and metabolism and respiration of existing SOC. We are studying the resilience of the microbial community, and the vulnerability of the soil carbon reservoirs, to changing climate conditions using a reciprocal soil transplant experiment initiated in 1994 in eastern Washington. Soil cores were reciprocally transplanted between two elevations (310 m and 844 m); the lower site is warmer and drier with 0.8% soil carbon, and the upper site is cooler and wetter with 1.8% soil carbon. We resampled these cores in 2012-13 to analyze the structure of the microbial community, biochemical activities of carbohydrate-active enzymes, and the soil carbon and nitrogen content. We hypothesized that microbial and biochemical dynamics developed under cool, moist conditions would destabilize under hot, dry conditions, such that carbon and nitrogen losses would be faster in warmer climate soils than the accruals in cooler climate soils. Metagenomics data analyses show that the microbial communities below 5 cm depth in the transplanted soils are most similar to those in the native and control soils from their original (pre-1994) location, whereas the surface microbial community has been influenced by their new (post-1994) location. Enzyme activities are highest in soils from the cooler, moister location, and the activities of the reciprocally transplanted soils are shifting toward the activities typical of their new location. Integration of these results with high-resolution mass spectrometry data of the soil carbon moieties will contribute to our fundamental understanding of climate change effects on the terrestrial ecosystem carbon cycle.

  17. Contrasting contributions of phonological short-term memory and long-term knowledge to vocabulary learning in a foreign language.

    Masoura, Elvira V; Gathercole, Susan E

    2005-01-01

    The contributions of phonological short-term memory and existing foreign vocabulary knowledge to the learning of new words in a second language were compared in a sample of 40 Greek children studying English at school. The children's speed of learning new English words in a paired-associate learning task was strongly influenced by their current English vocabulary, but was independent of phonological memory skill, indexed by nonword repetition ability. However, phonological memory performance was closely linked to English vocabulary scores. The findings suggest that in learners with considerable familiarity with a second language, foreign vocabulary acquisition is mediated largely by use of existing knowledge representations.

  18. Ganzfeld stimulation or sleep enhance long term motor memory consolidation compared to normal viewing in saccadic adaptation paradigm.

    Caroline Voges

    Full Text Available Adaptation of saccade amplitude in response to intra-saccadic target displacement is a type of implicit motor learning which is required to compensate for physiological changes in saccade performance. Once established trials without intra-saccadic target displacement lead to de-adaptation or extinction, which has been attributed either to extra-retinal mechanisms of spatial constancy or to the influence of the stable visual surroundings. Therefore we investigated whether visual deprivation ("Ganzfeld"-stimulation or sleep can partially maintain this motor learning compared to free viewing of the natural surroundings. Thirty-five healthy volunteers performed two adaptation blocks of 100 inward adaptation trials - interspersed by an extinction block - which were followed by a two-hour break with or without visual deprivation (VD. Using additional adaptation and extinction blocks short and long (4 weeks term memory of this implicit motor learning were tested. In the short term, motor memory tested immediately after free viewing was superior to adaptation performance after VD. In the long run, however, effects were opposite: motor memory and relearning of adaptation was superior in the VD conditions. This could imply independent mechanisms that underlie the short-term ability of retrieving learned saccadic gain and its long term consolidation. We suggest that subjects mainly rely on visual cues (i.e., retinal error in the free viewing condition which makes them prone to changes of the visual stimulus in the extinction block. This indicates the role of a stable visual array for resetting adapted saccade amplitudes. In contrast, visual deprivation (GS and sleep, might train subjects to rely on extra-retinal cues, e.g., efference copy or prediction to remap their internal representations of saccade targets, thus leading to better consolidation of saccadic adaptation.

  19. Facilitative Effects of Forgetting from Short-Term Memory on Growth of Long-Term Memory in Retardates

    Sperber, Richard D.

    1976-01-01

    Competing explanations of the beneficial effect of spacing in retardate discrimination learning were tested. Results are inconsistent with consolidation and rehearsal theories but support the prediction of the Geber, Greenfield, and House spacing model that forgetting from short-term memory facilities retardate learning. (Author/SB)

  20. Long-term potentiation and memory processes in the psychological works of Sigmund Freud and in the formation of neuropsychiatric symptoms.

    Centonze, D; Siracusano, A; Calabresi, P; Bernardi, G

    2005-01-01

    Far from disproving the model of mind functioning proposed by psychoanalysis, the recent advances in neuropsychiatrical research confirmed the crucial ideas of Sigmund Freud. The hypothesis that the origin of mental illnesses lies in the impossibility for a subject to erase the long-term effects of a remote adverse event is in tune with the view that several psychiatric disturbances reflect the activation of aberrant unconscious memory processes. Freud's insights did not stop here, but went on to describe in an extremely precise manner the neural mechanisms of memory formation almost a century before the description of long-term synaptic potentiation.

  1. X11beta rescues memory and long-term potentiation deficits in Alzheimer's disease APPswe Tg2576 mice.

    Mitchell, Jacqueline C

    2009-12-01

    Increased production and deposition of amyloid beta-protein (Abeta) are believed to be key pathogenic events in Alzheimer\\'s disease. As such, routes for lowering cerebral Abeta levels represent potential therapeutic targets for Alzheimer\\'s disease. X11beta is a neuronal adaptor protein that binds to the intracellular domain of the amyloid precursor protein (APP). Overexpression of X11beta inhibits Abeta production in a number of experimental systems. However, whether these changes to APP processing and Abeta production induced by X11beta overexpression also induce beneficial effects to memory and synaptic plasticity are not known. We report here that X11beta-mediated reduction in cerebral Abeta is associated with normalization of both cognition and in vivo long-term potentiation in aged APPswe Tg2576 transgenic mice that model the amyloid pathology of Alzheimer\\'s disease. Overexpression of X11beta itself has no detectable adverse effects upon mouse behaviour. These findings support the notion that modulation of X11beta function represents a therapeutic target for Abeta-mediated neuronal dysfunction in Alzheimer\\'s disease.

  2. Role of protein synthesis and DNA methylation in the consolidation and maintenance of long-term memory in Aplysia

    Pearce, Kaycey; Cai, Diancai; Roberts, Adam C; Glanzman, David L

    2017-01-01

    Previously, we reported that long-term memory (LTM) in Aplysia can be reinstated by truncated (partial) training following its disruption by reconsolidation blockade and inhibition of PKM (Chen et al., 2014). Here, we report that LTM can be induced by partial training after disruption of original consolidation by protein synthesis inhibition (PSI) begun shortly after training. But when PSI occurs during training, partial training cannot subsequently establish LTM. Furthermore, we find that inhibition of DNA methyltransferase (DNMT), whether during training or shortly afterwards, blocks consolidation of LTM and prevents its subsequent induction by truncated training; moreover, later inhibition of DNMT eliminates consolidated LTM. Thus, the consolidation of LTM depends on two functionally distinct phases of protein synthesis: an early phase that appears to prime LTM; and a later phase whose successful completion is necessary for the normal expression of LTM. Both the consolidation and maintenance of LTM depend on DNA methylation. DOI: http://dx.doi.org/10.7554/eLife.18299.001 PMID:28067617

  3. Very long-term memories may be stored in the pattern of holes in the perineuronal net.

    Tsien, Roger Y

    2013-07-23

    A hypothesis and the experiments to test it propose that very long-term memories, such as fear conditioning, are stored as the pattern of holes in the perineuronal net (PNN), a specialized ECM that envelops mature neurons and restricts synapse formation. The 3D intertwining of PNN and synapses would be imaged by serial-section EM. Lifetimes of PNN vs. intrasynaptic components would be compared with pulse-chase (15)N labeling in mice and (14)C content in human cadaver brains. Genetically encoded indicators and antineoepitope antibodies should improve spatial and temporal resolution of the in vivo activity of proteases that locally erode PNN. Further techniques suggested include genetic KOs, better pharmacological inhibitors, and a genetically encoded snapshot reporter, which will capture the pattern of activity throughout a large ensemble of neurons at a time precisely defined by the triggering illumination, drive expression of effector genes to mark those cells, and allow selective excitation, inhibition, or ablation to test their functional importance. The snapshot reporter should enable more precise inhibition or potentiation of PNN erosion to compare with behavioral consequences. Finally, biosynthesis of PNN components and proteases would be imaged.

  4. Effects of varying presentation time on long-term recognition memory for scenes: Verbatim and gist representations.

    Ahmad, Fahad N; Moscovitch, Morris; Hockley, William E

    2016-11-17

    Konkle, Brady, Alvarez and Oliva (Psychological Science, 21, 1551-1556, 2010) showed that participants have an exceptional long-term memory (LTM) for photographs of scenes. We examined to what extent participants' exceptional LTM for scenes is determined by presentation time during encoding. In addition, at retrieval, we varied the nature of the lures in a forced-choice recognition task so that they resembled the target in gist (i.e., global or categorical) information, but were distinct in verbatim information (e.g., an "old" beach scene and a similar "new" beach scene; exemplar condition) or vice versa (e.g., a beach scene and a new scene from a novel category; novel condition). In Experiment 1, half of the list of scenes was presented for 1 s, whereas the other half was presented for 4 s. We found lower performance for shorter study presentation time in the exemplar test condition and similar performance for both study presentation times in the novel test condition. In Experiment 2, participants showed similar performance in an exemplar test for which the lure was of a different category but a category that was used at study. In Experiment 3, when presentation time was lowered to 500 ms, recognition accuracy was reduced in both novel and exemplar test conditions. A less detailed memorial representation of the studied scene containing more gist (i.e., meaning) than verbatim (i.e., surface or perceptual details) information is retrieved from LTM after a short compared to a long study presentation time. We conclude that our findings support fuzzy-trace theory.

  5. A VLSI recurrent network of integrate-and-fire neurons connected by plastic synapses with long-term memory.

    Chicca, E; Badoni, D; Dante, V; D'Andreagiovanni, M; Salina, G; Carota, L; Fusi, S; Del Giudice, P

    2003-01-01

    Electronic neuromorphic devices with on-chip, on-line learning should be able to modify quickly the synaptic couplings to acquire information about new patterns to be stored (synaptic plasticity) and, at the same time, preserve this information on very long time scales (synaptic stability). Here, we illustrate the electronic implementation of a simple solution to this stability-plasticity problem, recently proposed and studied in various contexts. It is based on the observation that reducing the analog depth of the synapses to the extreme (bistable synapses) does not necessarily disrupt the performance of the device as an associative memory, provided that 1) the number of neurons is large enough; 2) the transitions between stable synaptic states are stochastic; and 3) learning is slow. The drastic reduction of the analog depth of the synaptic variable also makes this solution appealing from the point of view of electronic implementation and offers a simple methodological alternative to the technological solution based on floating gates. We describe the full custom analog very large-scale integration (VLSI) realization of a small network of integrate-and-fire neurons connected by bistable deterministic plastic synapses which can implement the idea of stochastic learning. In the absence of stimuli, the memory is preserved indefinitely. During the stimulation the synapse undergoes quick temporary changes through the activities of the pre- and postsynaptic neurons; those changes stochastically result in a long-term modification of the synaptic efficacy. The intentionally disordered pattern of connectivity allows the system to generate a randomness suited to drive the stochastic selection mechanism. We check by a suitable stimulation protocol that the stochastic synaptic plasticity produces the expected pattern of potentiation and depression in the electronic network.

  6. The effects of prolonged administration of norepinephrine reuptake inhibitors on long-term potentiation in dentate gyrus, and on tests of spatial and object recognition memory in rats.

    Walling, Susan G; Milway, J Stephen; Ingram, Matthew; Lau, Catherine; Morrison, Gillian; Martin, Gerard M

    2016-02-01

    Phasic norepinephrine (NE) release events are involved in arousal, novelty detection and in plasticity processes underlying learning and memory in mammalian systems. Although the effects of phasic NE release events on plasticity and memory are prevalently documented, it is less understood what effects chronic NE reuptake inhibition and sustained increases in noradrenergic tone, might have on plasticity and cognitive processes in rodent models of learning and memory. This study investigates the effects of chronic NE reuptake inhibition on hippocampal plasticity and memory in rats. Rats were administered NE reuptake inhibitors (NRIs) desipramine (DMI; 0, 3, or 7.5mg/kg/day) or nortriptyline (NTP; 0, 10 or 20mg/kg/day) in drinking water. Long-term potentiation (LTP; 200 Hz) of the perforant path-dentate gyrus evoked potential was examined in urethane anesthetized rats after 30-32 days of DMI treatment. Short- (4-h) and long-term (24-h) spatial memory was tested in separate rats administered 0 or 7.5mg/kg/day DMI (25-30 days) using a two-trial spatial memory test. Additionally, the effects of chronically administered DMI and NTP were tested in rats using a two-trial, Object Recognition Test (ORT) at 2- and 24-h after 45 and 60 days of drug administration. Rats administered 3 or 7.5mg/kg/day DMI had attenuated LTP of the EPSP slope but not the population spike at the perforant path-dentate gyrus synapse. Short- and long-term memory for objects is differentially disrupted in rats after prolonged administration of DMI and NTP. Rats that were administered 7.5mg/kg/day DMI showed decreased memory for a two-trial spatial task when tested at 4-h. In the novel ORT, rats receiving 0 or 7.5mg/kg/day DMI showed a preference for the arm containing a Novel object when tested at both 2- and 24-h demonstrating both short- and long-term memory retention of the Familiar object. Rats that received either dose of NTP or 3mg/kg/day DMI showed impaired memory at 2-h, however this

  7. Sampling design for long-term regional trends in marine rocky intertidal communities

    Irvine, Gail V.; Shelley, Alice

    2013-01-01

    Probability-based designs reduce bias and allow inference of results to the pool of sites from which they were chosen. We developed and tested probability-based designs for monitoring marine rocky intertidal assemblages at Glacier Bay National Park and Preserve (GLBA), Alaska. A multilevel design was used that varied in scale and inference. The levels included aerial surveys, extensive sampling of 25 sites, and more intensive sampling of 6 sites. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope ≤30° was rare. This unexpected finding illustrated one value of probability-based surveys and led to a shift in the target habitat type to include steeper, more mixed rocky habitat. Subsequently, we evaluated the statistical power of different sampling methods and sampling strategies to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles Balanomorpha, the mussel Mytilus trossulus, and the rockweed Fucus distichus subsp. evanescens. There was greatest power to detect trends in Mytilus and lesser power for barnacles and Fucus. Because of its greater power, the extensive, coarse-grained sampling scheme was adopted in subsequent years over the intensive, fine-grained scheme. The sampling attributes that had the largest effects on power included sampling of “vertical” line transects (vs. horizontal line transects or quadrats) and increasing the number of sites. We also evaluated the power of several management-set parameters. Given equal sampling effort, sampling more sites fewer times had greater power. The information gained through intertidal monitoring is likely to be useful in assessing changes due to climate, including ocean acidification; invasive species; trampling effects; and oil spills.

  8. Effects of Long-Term Storage Time and Original Sampling Month on Biobank Plasma Protein Concentrations.

    Enroth, Stefan; Hallmans, Göran; Grankvist, Kjell; Gyllensten, Ulf

    2016-10-01

    The quality of clinical biobank samples is crucial to their value for life sciences research. A number of factors related to the collection and storage of samples may affect the biomolecular composition. We have studied the effect of long-time freezer storage, chronological age at sampling, season and month of the year and on the abundance levels of 108 proteins in 380 plasma samples collected from 106 Swedish women. Storage time affected 18 proteins and explained 4.8-34.9% of the observed variance. Chronological age at sample collection after adjustment for storage-time affected 70 proteins and explained 1.1-33.5% of the variance. Seasonal variation had an effect on 15 proteins and month (number of sun hours) affected 36 proteins and explained up to 4.5% of the variance after adjustment for storage-time and age. The results show that freezer storage time and collection date (month and season) exerted similar effect sizes as age on the protein abundance levels. This implies that information on the sample handling history, in particular storage time, should be regarded as equally prominent covariates as age or gender and need to be included in epidemiological studies involving protein levels.

  9. Kaolin-induced ventriculomegaly at weaning produces long-term learning, memory, and motor deficits in rats.

    Williams, Michael T; Braun, Amanda A; Amos-Kroohs, Robyn M; McAllister, James P; Lindquist, Diana M; Mangano, Francesco T; Vorhees, Charles V; Yuan, Weihong

    2014-06-01

    Ventriculomegaly occurs when there is imbalance between creation and absorption of cerebrospinal fluid (CSF); even when treated, long-term behavioral changes occur. Kaolin injection in the cisterna magna of rats produces an obstruction of CSF outflow and models one type of hydrocephalus. Previous research with this model shows that neonatal onset has mixed effects on Morris water maze (MWM) and motoric performance; we hypothesized that this might be because the severity of ventricular enlargement was not taken into consideration. In the present experiment, rats were injected with kaolin or saline on postnatal day (P)21 and analyzed in subgroups based on Evan's ratios (ERs) of the severity of ventricular enlargement at the end of testing to create 4 subgroups from least to most severe: ER0.4-0.5, ER0.51-0.6, ER0.61-0.7, and ER0.71-0.82, respectively. Locomotor activity (dry land and swimming), acoustic startle with prepulse inhibition (PPI), and MWM performance were tested starting on P28 (122cm maze) and again on P42 (244cm maze). Kaolin-treated animals weighed significantly less than controls at all times. Differences in locomotor activity were seen at P42 but not P28. On P28 there was an increase in PPI for all but the least severe kaolin-treated group, but no difference at P42 compared with controls. In the MWM at P28, all kaolin-treated groups had longer path lengths than controls, but comparable swim speeds. With the exception of the least severe group, probe trial performance was worse in the kaolin-treated animals. On P42, only the most severely affected kaolin-treated group showed deficits compared with control animals. This group showed no MWM learning and no memory for the platform position during probe trial testing. Swim speed was unaffected, indicating motor deficits were not responsible for impaired learning and memory. These findings indicate that kaolin-induced ventriculomegaly in rats interferes with cognition regardless of the final enlargement of

  10. Long-term room temperature preservation of corpse soft tissue: an approach for tissue sample storage

    Caputo Mariela

    2011-08-01

    Full Text Available Abstract Background Disaster victim identification (DVI represents one of the most difficult challenges in forensic sciences, and subsequent DNA typing is essential. Collected samples for DNA-based human identification are usually stored at low temperature to halt the degradation processes of human remains. We have developed a simple and reliable procedure for soft tissue storage and preservation for DNA extraction. It ensures high quality DNA suitable for PCR-based DNA typing after at least 1 year of room temperature storage. Methods Fragments of human psoas muscle were exposed to three different environmental conditions for diverse time periods at room temperature. Storage conditions included: (a a preserving medium consisting of solid sodium chloride (salt, (b no additional substances and (c garden soil. DNA was extracted with proteinase K/SDS followed by organic solvent treatment and concentration by centrifugal filter devices. Quantification was carried out by real-time PCR using commercial kits. Short tandem repeat (STR typing profiles were analysed with 'expert software'. Results DNA quantities recovered from samples stored in salt were similar up to the complete storage time and underscored the effectiveness of the preservation method. It was possible to reliably and accurately type different genetic systems including autosomal STRs and mitochondrial and Y-chromosome haplogroups. Autosomal STR typing quality was evaluated by expert software, denoting high quality profiles from DNA samples obtained from corpse tissue stored in salt for up to 365 days. Conclusions The procedure proposed herein is a cost efficient alternative for storage of human remains in challenging environmental areas, such as mass disaster locations, mass graves and exhumations. This technique should be considered as an additional method for sample storage when preservation of DNA integrity is required for PCR-based DNA typing.

  11. Satellite tagging and biopsy sampling of killer whales at subantarctic Marion Island: effectiveness, immediate reactions and long-term responses.

    Ryan R Reisinger

    Full Text Available Remote tissue biopsy sampling and satellite tagging are becoming widely used in large marine vertebrate studies because they allow the collection of a diverse suite of otherwise difficult-to-obtain data which are critical in understanding the ecology of these species and to their conservation and management. Researchers must carefully consider their methods not only from an animal welfare perspective, but also to ensure the scientific rigour and validity of their results. We report methods for shore-based, remote biopsy sampling and satellite tagging of killer whales Orcinus orca at Subantarctic Marion Island. The performance of these methods is critically assessed using 1 the attachment duration of low-impact minimally percutaneous satellite tags; 2 the immediate behavioural reactions of animals to biopsy sampling and satellite tagging; 3 the effect of researcher experience on biopsy sampling and satellite tagging; and 4 the mid- (1 month and long- (24 month term behavioural consequences. To study mid- and long-term behavioural changes we used multievent capture-recapture models that accommodate imperfect detection and individual heterogeneity. We made 72 biopsy sampling attempts (resulting in 32 tissue samples and 37 satellite tagging attempts (deploying 19 tags. Biopsy sampling success rates were low (43%, but tagging rates were high with improved tag designs (86%. The improved tags remained attached for 26±14 days (mean ± SD. Individuals most often showed no reaction when attempts missed (66% and a slight reaction-defined as a slight flinch, slight shake, short acceleration, or immediate dive-when hit (54%. Severe immediate reactions were never observed. Hit or miss and age-sex class were important predictors of the reaction, but the method (tag or biopsy was unimportant. Multievent trap-dependence modelling revealed considerable variation in individual sighting patterns; however, there were no significant mid- or long-term changes

  12. Obesogenic memory can confer long-term increases in adipose tissue but not liver inflammation and insulin resistance after weight loss

    J. Schmitz

    2016-05-01

    Conclusions: These results demonstrate that although sustained weight loss improves systemic glucose homeostasis, primarily through improved inflammation and insulin action in liver, a remarkable obesogenic memory can confer long-term increases in adipose tissue inflammation and insulin resistance in mice as well as in a significant subpopulation of obese patients.

  13. Long-Term Memory for Place Learning Is Facilitated by Expression of cAMP Response Element-Binding Protein in the Dorsal Hippocampus

    Brightwell, Jennifer J.; Smith, Clayton A.; Neve, Rachael L.; Colombo, Paul J.

    2007-01-01

    Extensive research has shown that the hippocampus is necessary for consolidation of long-term spatial memory in rodents. We reported previously that rats using a place strategy to solve a cross maze task showed sustained phosphorylation of hippocampus cyclic AMP response element-binding protein (CREB), a transcription factor implicated in…

  14. Hippocampal Overexpression of Mutant CREB Blocks Long-Term, but Not Short-Term Memory for a Socially Transmitted Food Preference

    Brightwell, Jennifer J.; Countryman, Renee A.; Neve, Rachael L.; Colombo, Paul J.; Smith, Clayton A.

    2005-01-01

    Phosphorylation of the transcription factor CREB on Ser133 is implicated in the establishment of long-term memory for hippocampus-dependent tasks, including spatial learning and contextual fear conditioning. We reported previously that training on a hippocampus-dependent social transmission of food preference (STFP) task increases CREB…

  15. An Exemplar-Familiarity Model Predicts Short-Term and Long-Term Probe Recognition across Diverse Forms of Memory Search

    Nosofsky, Robert M.; Cox, Gregory E.; Cao, Rui; Shiffrin, Richard M.

    2014-01-01

    Experiments were conducted to test a modern exemplar-familiarity model on its ability to account for both short-term and long-term probe recognition within the same memory-search paradigm. Also, making connections to the literature on attention and visual search, the model was used to interpret differences in probe-recognition performance across…

  16. Protein Synthesis-Dependent Long-Term Memory Induced by One Single Associative Training Trial in the Parasitic Wasp Lariophagus distinguendus

    Steidle, Johannes L. M.; Collatz, Jana; Muller, Caroline

    2006-01-01

    Protein synthesis-dependent long-term memory in Apis mellifera and Drosophila melanogaster is formed after multiple trainings that are spaced in time. The parasitic wasp Lariophagus distinguendus remarkably differs from these species. It significantly responds to the artificial odor furfurylheptanoate (FFH) in olfactometer experiments, when this…

  17. The E3 Ligase APC/C-Cdh1 Is Required for Associative Fear Memory and Long-Term Potentiation in the Amygdala of Adult Mice

    Pick, Joseph E.; Malumbres, Marcos; Klann, Eric

    2013-01-01

    The anaphase promoting complex/cyclosome (APC/C) is an E3 ligase regulated by Cdh1. Beyond its role in controlling cell cycle progression, APC/C-Cdh1 has been detected in neurons and plays a role in long-lasting synaptic plasticity and long-term memory. Herein, we further examined the role of Cdh1 in synaptic plasticity and memory by generating…

  18. The Peg-Word Mnemonic Facilitates Immediate but Not Long-Term Memory in Fifth-Grade Children.

    Krinsky, Richard; Krinsky, Suzanne G.

    1994-01-01

    Two experiments examined immediate and long-term serial list learning effects for common nouns for 42 fifth graders. Results provide additional evidence that long-term forgetting may be greater for learners who receive mnemonic instruction than for untrained controls, in spite of some immediate enhanced recall. (SLD)

  19. The Effect of Zinc Supplementation of Lactating Rats on Short-Term and Long-Term Memory of Their Male Offspring

    Mohammad Karami

    2013-12-01

    Full Text Available Background: In this study the effect of zinc chloride (ZnCl2 administration on the short-term and long-term memory of rats were assessed. Methods: We enrolled six groups of adult female and control group of eight Wistar rats in each group. One group was control group with free access to food and water, and five groups drunk zinc chloride in different doses (20, 30, 50, 70 and 100 mg/kg/day in drinking water for two weeks during lactation .One month after birth, a shuttle box used to short- term and long-term memory and the latency in entering the dark chamber as well. Results: This experiment showed that maternal 70 mg/kg dietary zinc during lactation influenced the working memory of rats’ offspring in all groups. Rats received 100 mg/kg/day zinc during lactation so they had significant impairment in working memory (short-term of their offspring (P<0.05. There was no significant difference in reference (long-term memory of all groups. Conclusion: Drug consumption below70 mg/kg/day zinc chloride during lactation had no effect. While enhanced 100 mg/ kg/ day zinc in lactating rats could cause short-term memory impairment.

  20. Differential roles for Nr4a1 and Nr4a2 in object location vs. object recognition long-term memory.

    McNulty, Susan E; Barrett, Ruth M; Vogel-Ciernia, Annie; Malvaez, Melissa; Hernandez, Nicole; Davatolhagh, M Felicia; Matheos, Dina P; Schiffman, Aaron; Wood, Marcelo A

    2012-11-16

    Nr4a1 and Nr4a2 are transcription factors and immediate early genes belonging to the nuclear receptor Nr4a family. In this study, we examine their role in long-term memory formation for object location and object recognition. Using siRNA to block expression of either Nr4a1 or Nr4a2, we found that Nr4a2 is necessary for both long-term memory for object location and object recognition. In contrast, Nr4a1 appears to be necessary only for object location. Indeed, their roles in these different types of long-term memory may be dependent on their expression in the brain, as NR4A2 was found to be expressed in hippocampal neurons (associated with object location memory) as well as in the insular and perirhinal cortex (associated with object recognition memory), whereas NR4A1 showed minimal neuronal expression in these cortical areas. These results begin to elucidate how NR4A1 and NR4A2 differentially contribute to object location versus object recognition memory.

  1. Long-term memory-based control of attention in multi-step tasks requires working memory: evidence from domain-specific interference.

    Foerster, Rebecca M; Carbone, Elena; Schneider, Werner X

    2014-01-01

    Evidence for long-term memory (LTM)-based control of attention has been found during the execution of highly practiced multi-step tasks. However, does LTM directly control for attention or are working memory (WM) processes involved? In the present study, this question was investigated with a dual-task paradigm. Participants executed either a highly practiced visuospatial sensorimotor task (speed stacking) or a verbal task (high-speed poem reciting), while maintaining visuospatial or verbal information in WM. Results revealed unidirectional and domain-specific interference. Neither speed stacking nor high-speed poem reciting was influenced by WM retention. Stacking disrupted the retention of visuospatial locations, but did not modify memory performance of verbal material (letters). Reciting reduced the retention of verbal material substantially whereas it affected the memory performance of visuospatial locations to a smaller degree. We suggest that the selection of task-relevant information from LTM for the execution of overlearned multi-step tasks recruits domain-specific WM.

  2. Long-term memory-based control of attention in multi-step tasks requires working memory: Evidence from domain-specific interference

    Rebecca Martina Foerster

    2014-05-01

    Full Text Available Evidence for long-term memory (LTM-based control of attention has been found during the execution of highly practiced multi-step tasks. However, does LTM directly control for attention or are working memory (WM processes involved? In the present study, this question was investigated with a dual-task paradigm. Participants executed either a highly practiced visuospatial sensorimotor task (speed stacking or a verbal task (high-speed poem reciting, while maintaining visuospatial or verbal information in WM. Results revealed unidirectional and domain-specific interference. Neither speed stacking nor high-speed poem reciting was influenced by WM retention. Stacking disrupted the retention of visuospatial locations, but did not modify memory performance of verbal material (letters. Reciting reduced the retention of verbal material substantially whereas it affected the memory performance of visuospatial locations to a smaller degree. We suggest that the selection of task-relevant information from LTM for the execution of overlearned multi-step tasks recruits domain-specific WM.

  3. Long-term course of ADHD symptoms from childhood to early adulthood in a community sample.

    Döpfner, Manfred; Hautmann, Christopher; Görtz-Dorten, Anja; Klasen, Fionna; Ravens-Sieberer, Ulrike

    2015-06-01

    Comparatively little information is available from population-based studies on subgroup trajectories of attention-deficit/hyperactivity disorder (ADHD) core symptoms of inattention and hyperactivity-impulsivity (particularly as defined by DSM-IV and ICD-10). Recent report of a subgroup with high and increasing inattention symptoms across development requires replication. To identify the different trajectory subgroups for inattention, hyperactivity-impulsivity and total symptoms of ADHD in children and adolescents aged 7-19 years. Eleven birth cohorts from 2,593 families with children and adolescents who had parent ratings for the outcome measures of inattention, hyperactivity-impulsivity or total symptoms were considered. Data were analysed using an accelerated longitudinal design and growth mixture modelling was applied to detect subgroups. For all three outcome measures, three trajectories with low (78.3-83.3 %), moderate (13.4-18.8 %) and high (2.8-3.2 %) symptom levels were detected. Course within these subgroups was largely comparable across outcome domains. In general, a decrease in symptoms with age was observed in all severity subgroups, although the developmental course was stable for the high subgroups of inattention and total symptoms. About 3 % of children in a community-based sample follow a course with a high level of ADHD symptoms. In this high trajectory group, hyperactivity-impulsivity symptoms decrease with age from 7 to 19 years, whilst inattention and total symptoms are stable. There was no evidence for an increase in symptoms across childhood/adolescence in any of the severity groups.

  4. PKA Increases in the Olfactory Bulb Act as Unconditioned Stimuli and Provide Evidence for Parallel Memory Systems: Pairing Odor with Increased PKA Creates Intermediate- and Long-Term, but Not Short-Term, Memories

    Grimes, Matthew T.; Harley, Carolyn W.; Darby-King, Andrea; McLean, John H.

    2012-01-01

    Neonatal odor-preference memory in rat pups is a well-defined associative mammalian memory model dependent on cAMP. Previous work from this laboratory demonstrates three phases of neonatal odor-preference memory: short-term (translation-independent), intermediate-term (translation-dependent), and long-term (transcription- and…

  5. Response of Long-Term Memory to Molecular Changes of BDNF in Hippocampus in Various Intensities of Physical Activity

    Leonardo Lubis

    2016-09-01

    Full Text Available Objective: To analyze the physiological response of long-term memory (LTM to the molecular changes of brain-derived neurotrophic factor (BDNF in the hippocampus by the treatment of various intensities of physical activity. Methods: Subjects were 7–8 week old male Wistar rats weighed between 201–250 grams. This study was an experimental study with pre-(day-1 and post-(day-14 design. Molecular changes reflected by the changes in the expression of mRNA and protein of BDNF in the hippocampus. Treatment of physical activity on the subjects was running on the Animal Treadmill by grouping of the physical activity: light intensity at a speed of 10 m/min, moderate intensity at a speed of 20 m/min and heavy intensity at a speed of 30 m/min. The treatment’s duration was 30 minutes.Then, analysis of data on pre (day-1 and post (day-14 which were: LTM response based on travel time swimming test, the expression of mRNA (Ct and protein (% of BDNF in hippocampus based on RT-PCR and immunohistochemistry. Results: The results showed that moderate intensity group caused the better physiological and molecular responses than the other groups, as follows: travel time (0.6260 vs 0.7270 vs 0.9400 vs. 1.4000 seconds (p<0.05, mRNA BDNF expression (17.2320 vs 18.8800 vs 19.7540 vs 20.7750 Ct (p<0.05, and hippocampal BDNF protein expression. Conclusions: The study conclude that the moderate intensity is the best physical activity to improve LTM as showed by the BDNF mRNA expression as well as BDNF protein in hippocampus.

  6. Dietary Cholesterol Concentration and Duration Degrade Long-Term Memory of Classical Conditioning of the Rabbit’s Nictitating Membrane Response

    Bernard G. Schreurs

    2012-01-01

    Full Text Available A rabbit model of Alzheimer’s disease based on feeding a cholesterol diet for eight weeks shows sixteen hallmarks of the disease, including learning and memory changes. Although we have shown 2% cholesterol and copper in water can retard learning, other studies show feeding dietary cholesterol before learning can improve acquisition whereas feeding cholesterol after learning can degrade long-term memory. We explored this issue by manipulating cholesterol concentration and duration following classical trace conditioning of the rabbit’s nictitating membrane response and assessed conditioned responding after eight weeks on cholesterol. First, rabbits given trace classical conditioning followed by 0.5%, 1%, or 2% cholesterol for eight weeks showed body weight and serum cholesterol levels that were a function of dietary cholesterol. Although all concentrations of cholesterol showed some sign of retarding long-term memory, the level of memory retardation was correlated with serum cholesterol levels. Second, rabbits given trace conditioning followed by different durations of a 2% cholesterol diet combined with different durations of a 0% control diet for 8 weeks showed duration and timing of a 2% cholesterol diet were important in affecting recall. The data support the idea that dietary cholesterol may retard long-term memory.

  7. NMDA receptors in mouse anterior piriform cortex initialize early odor preference learning and L-type calcium channels engage for long-term memory.

    Mukherjee, Bandhan; Yuan, Qi

    2016-10-14

    The interactions of L-type calcium channels (LTCCs) and NMDA receptors (NMDARs) in memories are poorly understood. Here we investigated the specific roles of anterior piriform cortex (aPC) LTCCs and NMDARs in early odor preference memory in mice. Using calcium imaging in aPC slices, LTCC activation was shown to be dependent on NMDAR activation. Either D-APV (NMDAR antagonist) or nifedipine (LTCC antagonist) reduced somatic calcium transients in pyramidal cells evoked by lateral olfactory tract stimulation. However, nifedipine did not further reduce calcium in the presence of D-APV. In mice that underwent early odor preference training, blocking NMDARs in the aPC prevented short-term (3 hr) and long-term (24 hr) odor preference memory, and both memories were rescued when BayK-8644 (LTCC agonist) was co-infused. However, activating LTCCs in the absence of NMDARs resulted in loss of discrimination between the conditioned odor and a similar odor mixture at 3 hr. Elevated synaptic AMPAR expression at 3 hr was prevented by D-APV infusion but restored when LTCCs were directly activated, mirroring the behavioral outcomes. Blocking LTCCs prevented 24 hr memory and spared 3 hr memory. These results suggest that NMDARs mediate stimulus-specific encoding of odor memory while LTCCs mediate intracellular signaling leading to long-term memory.

  8. An Optimal Sampling Design for Observing and Validating Long-Term Leaf Area Index with Temporal Variations in Spatial Heterogeneities

    Yelu Zeng

    2015-01-01

    Full Text Available A sampling strategy to define elementary sampling units (ESUs for an entire site at the kilometer scale is an important step in the validation process for moderate-resolution leaf area index (LAI products. Current LAI-sampling strategies are unable to consider the vegetation seasonal changes and are better suited for single-day LAI product validation, whereas the increasingly used wireless sensor network for LAI measurement (LAINet requires an optimal sampling strategy across both spatial and temporal scales. In this study, we developed an efficient and robust LAI Sampling strategy based on Multi-temporal Prior knowledge (SMP for long-term, fixed-position LAI observations. The SMP approach employed multi-temporal vegetation index (VI maps and the vegetation classification map as a priori knowledge. The SMP approach minimized the multi-temporal bias of the VI frequency histogram between the ESUs and the entire site and maximized the nearest-neighbor index to ensure that ESUs were dispersed in the geographical space. The SMP approach was compared with four sampling strategies including random sampling, systematic sampling, sampling based on the land-cover map and a sampling strategy based on vegetation index prior knowledge using the PROSAIL model-based simulation analysis in the Heihe River basin. The results indicate that the ESUs selected using the SMP method spread more evenly in both the multi-temporal feature space and geographical space over the vegetation cycle. By considering the temporal changes in heterogeneity, the average root-mean-square error (RMSE of the LAI reference maps can be reduced from 0.12 to 0.05, and the relative error can be reduced from 6.1% to 2.2%. The SMP technique was applied to assign the LAINet ESU locations at the Huailai Remote Sensing Experimental Station in Beijing, China, from 4 July to 28 August 2013, to validate three MODIS C5 LAI products. The results suggest that the average R2, RMSE, bias and relative

  9. BAF53b, a Neuron-Specific Nucleosome Remodeling Factor, Is Induced after Learning and Facilitates Long-Term Memory Consolidation.

    Yoo, Miran; Choi, Kwang-Yeon; Kim, Jieun; Kim, Mujun; Shim, Jaehoon; Choi, Jun-Hyeok; Cho, Hye-Yeon; Oh, Jung-Pyo; Kim, Hyung-Su; Kaang, Bong-Kiun; Han, Jin-Hee

    2017-03-29

    Although epigenetic mechanisms of gene expression regulation have recently been implicated in memory consolidation and persistence, the role of nucleosome-remodeling is largely unexplored. Recent studies show that the functional loss of BAF53b, a postmitotic neuron-specific subunit of the BAF nucleosome-remodeling complex, results in the deficit of consolidation of hippocampus-dependent memory and cocaine-associated memory in the rodent brain. However, it is unclear whether BAF53b expression is regulated during memory formation and how BAF53b regulates fear memory in the amygdala, a key brain site for fear memory encoding and storage. To address these questions, we used viral vector approaches to either decrease or increase BAF53b function specifically in the lateral amygdala of adult mice in auditory fear conditioning paradigm. Knockdown of Baf53b before training disrupted long-term memory formation with no effect on short-term memory, basal synaptic transmission, and spine structures. We observed in our qPCR analysis that BAF53b was induced in the lateral amygdala neurons at the late consolidation phase after fear conditioning. Moreover, transient BAF53b overexpression led to persistently enhanced memory formation, which was accompanied by increase in thin-type spine density. Together, our results provide the evidence that BAF53b is induced after learning, and show that such increase of BAF53b level facilitates memory consolidation likely by regulating learning-related spine structural plasticity.SIGNIFICANCE STATEMENT Recent works in the rodent brain begin to link nucleosome remodeling-dependent epigenetic mechanism to memory consolidation. Here we show that BAF53b, an epigenetic factor involved in nucleosome remodeling, is induced in the lateral amygdala neurons at the late phase of consolidation after fear conditioning. Using specific gene knockdown or overexpression approaches, we identify the critical role of BAF53b in the lateral amygdala neurons for memory

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

    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

  11. Long-term stellar activity variations of stars from the HARPS M-dwarf sample: Comparison between activity indices

    da Silva, J Gomes; Bonfils, X

    2010-01-01

    We used four known chromospheric activity indicators to measure long-term activity variations in a sample of 23 M-dwarf stars from the HARPS planet search program. We compared the indices using weighted Pearson correlation coefficients and found that in general (i) the correlation between $S_{CaII}$ and \\ion{Na}{i} is very strong and does not depend on the activity level of the stars, (ii) the correlation between our $S_{CaII}$ and H$\\alpha$ seems to depend on the activity level of the stars, and (iii) there is no strong correlation between $S_{CaII}$ and \\ion{He}{i} for these type of stars.

  12. Long-term far-transfer effects of working memory training in children with ADHD: a randomized controlled trial.

    Bigorra, Aitana; Garolera, Maite; Guijarro, Silvina; Hervás, Amaia

    2016-08-01

    ADHD affects working memory (WM) and other executive functions (EFs) and thereby negatively impacts school performance, clinical symptoms and functional impairment. The main aim of this study was to analyse the efficacy of computerized WM training (CWMT) on EF rating scales. A secondary objective was to assess its efficacy on performance-based measures of EF (PBMEF), learning, clinical symptoms and functional impairment. 66 children with combined-type ADHD between 7 and 12 years of age from the Child and Adolescent Psychiatric Unit (Spain) were included in this randomized, double-blind, placebo-controlled, parallel-group clinical trial. The participants were randomized (1:1) to an experimental group (EG) (CWMT) (n = 36) or a control group (CG) (placebo training). Assessments were conducted at baseline (T0), 1-2 weeks (T1), and 6 months post-intervention (T2) with the administration of EF rating scales, PBMEF, measures of academic achievement, and questionnaires regarding clinical symptoms and functional impairment. Participants, parents, teachers and professionals who performed the cognitive assessments were blinded. Adjusted multiple linear regression analysis showed significant improvements in EF scales-parent version, from T1 to T2, on the metacognition index [p = 0.03, d' = -0.78 (95 % CI -1.28 to -0.27)] and on WM (also significant at T2-T0) and plan/organize subscales. Significant improvements were also noted in EF scales-teacher version, from T0 to T1 and T2, on the metacognitive index [p = 0.05, d' = -0.37 (95 % CI -0.86 to 0.12) T1-T0, p = 0.02, d' = -0.81 (95 % CI -1.31 to -0.30) T2-T0] and on the initiate, WM, monitor and shift subscales. There were also significant improvements in PBMEF, ADHD symptoms, and functional impairment. CWMT had a significant impact on ADHD deficits by achieving long-term far-transfer effects.

  13. Lidocaine injections targeting CA3 hippocampus impair long-term spatial memory and prevent learning-induced mossy fiber remodeling.

    Holahan, Matthew R; Routtenberg, Aryeh

    2011-05-01

    Learning a spatial location induces remodeling of the mossy fiber terminal field (MFTF) in the CA3 subfield of the dorsal hippocampus (Ramirez-Amaya et al. (2001) J Neurosci 21:7340-7348; Holahan et al. (2006) Hippocampus 16:560-570; Rekart et al. (2007a) Learn Mem 14:416-421). These fibers appear to grow from the stratum lucidum into distal stratum oriens. Is this axonal growth dependent on “repeated and persistent” neural activity in the CA3 region during training? To address this issue, we targeted local inactivation of the MFTF region in a post-training, consolidation paradigm. Male Wistar rats, bilaterally implanted with chronic indwelling cannulae aimed at the MFTF CA3 region, were trained on a hidden platform water maze task (10 trials per day for 5 days). Immediately after the 10th trial on each training day, rats were injected with lidocaine (4% w/v; 171 mM; n=7) or phosphate-buffered saline (PBS; n=7). Behavioral measures of latency, path length, and thigmotaxis were recorded, as was directional heading. A retention test (probe trial) was given 7 days after the last training day, and brains were subsequently processed for MFTF distribution (Timm's stain) and cannula location. Lidocaine treatment was found to block the learning-associated structural remodeling of the MFTF that was reported previously and observed in the PBS-injected controls. During training, the lidocaine group showed elevated latencies and a misdirected heading to locate the platform on the first trial of each training day. On the 7-day retention probe trial, the lidocaine-injected group showed poor retention indicated by the absence of a search bias in the area where the platform had been located during training. These data suggest that the reduction of neuronal activity in the CA3 region impairs long-term storage of spatial information. As this was associated with reduced MFTF structural remodeling, it provides initial anatomical and behavioral evidence for an activity

  14. A unique role of the cholera toxin A1-DD adjuvant for long-term plasma and memory B cell development.

    Bemark, Mats; Bergqvist, Peter; Stensson, Anneli; Holmberg, Anna; Mattsson, Johan; Lycke, Nils Y

    2011-02-01

    Adjuvants have traditionally been appreciated for their immunoenhancing effects, whereas their impact on immunological memory has largely been neglected. In this paper, we have compared three mechanistically distinct adjuvants: aluminum salts (Alum), Ribi (monophosphoryl lipid A), and the cholera toxin A1 fusion protein CTA1-DD. Their influence on long-term memory development was dramatically different. Whereas a single immunization i.p. with 4-hydroxy-3-nitrophenyl acetyl (NP)-chicken γ-globulin and adjuvant stimulated serum anti-NP IgG titers that were comparable at 5 wk, CTA1-DD-adjuvanted responses were maintained for >16 mo with a half-life of anti-NP IgG ∼36 wk, but DD dose-dependent increase in germinal center (GC) size and numbers was found, with >60% of splenic B cell follicles hosting GC at an optimal CTA1-DD dose. Roughly 7% of these GC were NP specific. This GC-promoting effect correlated well with the persistence of long-term plasma cells in the bone marrow and memory B cells in the spleen. CTA1-DD also facilitated increased somatic hypermutation and affinity maturation of NP-specific IgG Abs in a dose-dependent fashion, hence arguing that large GC not only promotes higher Ab titers but also high-quality Ab production. Adoptive transfer of splenic CD80(+), but not CD80(-), B cells, at 1 y after immunization demonstrated functional long-term anti-NP IgG and IgM memory cells. To our knowledge, this is the first report to specifically compare and document that adjuvants can differ considerably in their support of long-term immune responses. Differential effects on the GC reaction appear to be the basis for these differences.

  15. Differential Roles for "Nr4a1" and "Nr4a2" in Object Location vs. Object Recognition Long-Term Memory

    McNulty, Susan E.; Barrett, Ruth M.; Vogel-Ciernia, Annie; Malvaez, Melissa; Hernandez, Nicole; Davatolhagh, M. Felicia; Matheos, Dina P.; Schiffman, Aaron; Wood, Marcelo A.

    2012-01-01

    "Nr4a1" and "Nr4a2" are transcription factors and immediate early genes belonging to the nuclear receptor Nr4a family. In this study, we examine their role in long-term memory formation for object location and object recognition. Using siRNA to block expression of either "Nr4a1" or "Nr4a2", we found that "Nr4a2" is necessary for both long-term…

  16. Modulation of Long-Term Potentiation of Cortico-Amygdala Synaptic Responses and Auditory Fear Memory by Dietary Polyunsaturated Fatty Acid

    Yamada, Daisuke; Wada, Keiji; Sekiguchi, Masayuki

    2016-01-01

    Converging evidence suggests that an imbalance of ω3 to ω6 polyunsaturated fatty acid (PUFA) in the brain is involved in mental illnesses such as anxiety disorders. However, the underlying mechanism is unknown. We previously reported that the dietary ratio of ω3 to ω6 PUFA alters this ratio in the brain, and influences contextual fear memory. In addition to behavioral change, enhancement of cannabinoid CB1 receptor-mediated short-term synaptic plasticity and facilitation of the agonist sensitivity of CB1 receptors have been observed in excitatory synaptic responses in the basolateral nucleus of the amygdala (BLA). However, it is not known whether long-term synaptic plasticity in the amygdala is influenced by the dietary ratio of ω3 to ω6 PUFA. In the present study, we examined long-term potentiation (LTP) of optogenetically-evoked excitatory synaptic responses in synapses between the terminal of the projection from the auditory cortex (ACx) and the pyramidal cells in the lateral nucleus of the amygdala. We found that LTP in this pathway was attenuated in mice fed with a high ω3 to ω6 PUFA ratio diet (0.97), compared with mice fed with a low ω3 to ω6 PUFA ratio diet (0.14). Furthermore, mice in the former condition showed reduced fear responses in an auditory fear conditioning test, compared with mice in the latter condition. In both electrophysiological and behavioral experiments, the effect of a diet with a high ω3 to ω6 PUFA diet ratio was completely blocked by treatment with a CB1 receptor antagonist. Furthermore, a significant reduction was observed in cholesterol content, but not in the level of an endogenous CB1 receptor agonist, 2-arachidonoylglycerol (2-AG), in brain samples containing the amygdala. These results suggest that the balance of ω3 to ω6 PUFA has an impact on fear memory and cortico-amygdala synaptic plasticity, both in a CB1 receptor–dependent manner. PMID:27601985

  17. Immediate recall influences the effects of pre-encoding stress on emotional episodic long-term memory consolidation in healthy young men.

    Wolf, Oliver T

    2012-05-01

    The stress-associated activation of the hypothalamus-pituitary-adrenal axis influences memory. Several studies have supported the notion that post-learning stress enhances memory consolidation, while pre-retrieval stress impairs retrieval. Findings regarding the effects of pre-encoding stress, in contrast, have been rather inconsistent. In the current two studies, the impact of an immediate retrieval task on these effects was explored. In the first study, 24 healthy young male participants were exposed to a psychosocial laboratory stressor (Trier Social Stress Test) or a control condition before viewing positive, negative, and neutral photographs, which were accompanied by a brief narrative. Immediate as well as delayed (24 h later) free recall was assessed. Stress was expected to enhance emotional long-term memory without affecting immediate recall performance. Stress caused a significant increase in salivary cortisol concentrations but had no significant effects on immediate or delayed retrieval performance, even though a trend toward poorer memory of the stress group was apparent. Based on these findings, the second experiment tested the hypothesis that the beneficial effects of stress on emotional long-term memory performance might be abolished by an immediate recall test. In the second study (n = 32), the same design was used, except for the omission of the immediate retrieval test. This time stressed participants recalled significantly more negative photographs compared to the control group. The present study indicates that an immediate retrieval attempt of material studied after stress exposure can prevent or even reverse the beneficial effects of pre-encoding stress on emotional long-term memory consolidation.

  18. Impaired recruitment of seizure-generated neurons into functional memory networks of the adult dentate gyrus following long-term amygdala kindling.

    Fournier, Neil M; Botterill, Justin J; Marks, Wendie N; Guskjolen, Axel J; Kalynchuk, Lisa E

    2013-06-01

    Epileptic seizures increase the birth of new neurons in the adult hippocampus. Although the consequences of aberrant neurogenesis on behavior are not fully understood, one hypothesis is that seizure-generated neurons might form faulty circuits that disrupt hippocampal functions, such as learning and memory. In the present study, we employed long-term amygdala kindling (i.e., rats receive 99-electrical stimulations) to examine the effect of repeated seizures on hippocampal neurogenesis and behavior. We labeled seizure-generated cells with the proliferation marker BrdU after 30-stimulations and continued kindling for an additional 4weeks to allow newborn neurons to mature under conditions of repeated seizures. After kindling was complete, rats were tested in a trace fear conditioning task and sacrificed 2h later to examine if 4-week old newborn cells were recruited into circuits involved in the retrieval of emotional memory. Compared to non-kindled controls, long-term kindled rats showed significant impairments in fear memory reflected in a decrease in conditioned freezing to both tone and contextual cues during testing. Moreover, long-term kindling also prevented the activation of 4-week old newborn cells in response to fear memory retrieval. These results indicate that the presence of seizure activity during cell maturation impedes the ability of new neurons to integrate properly into circuits important in memory formation. Together, our findings suggest that aberrant seizure-induced neurogenesis might contribute to the development of learning impairments in chronic epilepsy and raise the possibility that targeting the reduced activation of adult born neurons could represent a beneficial strategy to reverse cognitive deficits in some epileptic patients.

  19. Memory deficits in long-term survivors of childhood brain tumors may primarily reflect general cognitive dysfunctions

    Reimers, Tonny Solveig; Mortensen, Erik Lykke; Schmiegelow, Kjeld

    2007-01-01

    To analyze the impact of potential predictors on memory performance in survivors of childhood brain tumors and to examine whether deficits in memory after radiotherapy (RT) should be considered part of a more global mental dysfunction.......To analyze the impact of potential predictors on memory performance in survivors of childhood brain tumors and to examine whether deficits in memory after radiotherapy (RT) should be considered part of a more global mental dysfunction....

  20. Cyclic Nucleotide-Gated Channels, Calmodulin, Adenylyl Cyclase, and Calcium/Calmodulin-Dependent Protein Kinase II Are Required for Late, but Not Early, Long-Term Memory Formation in the Honeybee

    Matsumoto, Yukihisa; Sandoz, Jean-Christophe; Devaud, Jean-Marc; Lormant, Flore; Mizunami, Makoto; Giurfa, Martin

    2014-01-01

    Memory is a dynamic process that allows encoding, storage, and retrieval of information acquired through individual experience. In the honeybee "Apis mellifera," olfactory conditioning of the proboscis extension response (PER) has shown that besides short-term memory (STM) and mid-term memory (MTM), two phases of long-term memory (LTM)…

  1. Long-term memory was impaired in one-trial passive avoidance task of day-old chicks hatching from hypo-magnetic field space

    WANG Xuebin; XU Muling; LI Bing; LI Dongfeng; JIANG Jinchang

    2003-01-01

    The retained curve in one-trial passive avoidance task (OTPAT) of day-old chicks hatching from natural geomagnetic field (control groups) is consistent with the acknowledged three-phase model. The two dips are at the 20th min and the 60 min, and the avoidance rates (AR) to the red bead in short- and intermediate-term memory are 68.4% on average, while that in the long-term momory was 74.8%. The OTPAT retained curve of day-old chicks hatching from hypomagnetic field space (experimental groups) presents the marked timing effect. The two dips were at the 25th min and the 50th min, the avoidance rates to the red bead (ARR) in the short- and intermediate-term memory was 74.1% on an average, which was resembled to that in control group; however, the long-term memory appeared an obvious fluctuation. Compared with that in control groups, ARR and the deviation coefficient in experimental groups were decreased by 25.3% and increased by 1.3 times, respectively. That is to say, both the memory ability and stability in the experimental chicks declined. The result shows that the hypomagnetic field space has a negative effect on the development of chick brain function, and that cannot be negligible.

  2. Long-term sampling of dioxin-like substances from a clinker kiln stack using alternative fuels.

    Rivera-Austrui, J; Martinez, K; Marco-Almagro, L; Abalos, M; Abad, E

    2014-07-01

    The aim of this work is to characterize atmospheric emissions of polychlorinated dibenzo-p-dioxins (PCDDs)/polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) from a cement production plant where the existing clinker production line was completely replaced by a new state-of-the-art installation. The project started in April 2008 with the installation of a long-term sampling system in the stack of the clinker kiln that used petroleum coke as fuel; PCDD/PCDF and dl-PCB emissions were then evaluated for a two year period. To carry out the second part of the study, in 2010 the sampling system was moved to the new installation in which, apart from conventional fuel, recovered derived fuel (RDF) and WWTP sludge were used as alternative fuels. For both the old and new clinker kilns, PCDD/PCDF emission values were well below the limit established by the European Waste Incineration Directive 2000/76/CE (EWID) of 100 pg I-TEQ/Nm(3); values ranged from 0.43 to 2.02 and from 0.07 to 3.31 pg I-TEQ/Nm(3), respectively. dl-PCBs accounted for approximately 25% of the WHO-TEQ toxicity. These results prove that the installation is capable of reducing PCDD/PCDF and dl-PCB emissions when alternative fuels are integrated into the process. In the case of PCDDs/PCDFs, the major contributions to total TEQ were usually from 2,3,7,8-TCDD (owing to its relative abundance) and 2,3,4,7,8-PeCDF (due to its high I-TEF of 0.5); while for dl-PCBs, the major contribution was from PCB-126. The slight shift in the congener profile between the old and new installations was characterized and a regression model was proposed for dl-PCB emissions depending on the RDF flow rate in the clinker.

  3. Preservation of vaccine-induced long-term B cell memory and the effects of immunosuppressive treatment

    Ingelman-Sundberg, Hanna M.

    2015-01-01

    Immune memory after vaccination is largely dependent on the combination of antibody production from long-lived plasma cells, and a supporting pool of antigen-primed memory B cells. It has been observed that individuals with certain immunosuppressive conditions or treatments have a weakened B cell memory, but the mechanisms behind remain elusive. The aim of this thesis was to evaluate B cell immunity in healthy children, and how HIV-1 infection, antineoplastic therapy, and rheum...

  4. Long-term olfactory memories are stabilised via protein synthesis in Camponotus fellah ants

    Guerrieri, Fernando Javier; D'Ettorre, Patrizia; Deveaud, J-M.; Giurfa, M.

    2011-01-01

    Ants exhibit impressive olfactory learning abilities. Operant protocols in which ants freely choose between rewarded and nonrewarded odours have been used to characterise associative olfactory learning and memory. Yet, this approach precludes the use of invasive methods allowing the dissection of molecular bases of learning and memory. An open question is whether the memories formed upon olfactory learning that are retrievable several days after training are indeed based on de novo protein sy...

  5. Role of 5-HT1-7 receptors in short- and long-term memory for an autoshaping task: intrahippocampal manipulations.

    Liy-Salmeron, Gustavo; Meneses, Alfredo

    2007-05-25

    It was previously reported that brain areas containing serotonin (5-hydroxytryptamine, 5-HT) receptors mediate memory consolidation as well as short (STM)- and long-term memory (LTM). Here the effects of systemic and intrahippocampal administration of 5-HT agonists and antagonists on an autoshaping learning task were explored, which requires hippocampal translation and transduction as well as 5-HT receptors expression. As previously reported ketamine (glutamatergic antagonist) and two well-known amnesic drugs, scopolamine (cholinergic antagonist) and dizocilpine (NMDA antagonist) impaired STM but not LTM; dizocilpine even improved the latter. Since ketamine produces hallucinations and impairs memory in humans, we address the question if well-known antipsychotic haloperidol and clozapine might affect STM deficit. Indeed, systemic administration of clozapinememory deficits related to hippocampus and schizophrenia.

  6. Improvement in Memory and Brain Long-term Potentiation Deficits Due to Permanent Hypoperfusion/Ischemia by Grape Seed Extract in Rats

    Alireza Sarkaki

    2013-09-01

    Full Text Available   Objective(s: Cerebral hypoperfusion/ischemia (CHI is a neurological disease where impaired hippocampus electrical activity and cognition caused by a serial pathophysiological events. This study aimed to evaluate the effects of chronic oral administration of grape seed extract (GSE on passive avoidance memory and long-term potentiation (LTP after permanent bilateral common carotid arteries occlusion (2CCAO in male adult rats.   Materials and Methods: Thirty-two adult male Wistar rats were randomly divided into: 1 Sham+Veh, 2 Isch+Veh, 3 Sham+GSE, 4 Isch+GSE. In order to make 2CCAO as an animal model of CHI, carotid arteries were ligatured and then cut bilaterally. To evaluation of passive avoidance memory, step-down latency (STL was measured and LTP was recorded from hippocampal dentate gyrus (DG after high frequency stimulation (HFS in all rats. Results: We found that memory was significantly impaired in rats after CHI (P

  7. Olfaction, Emotion, and the Amygdala: arousal-dependent modulation of long-term autobiographical memory and its association with olfaction: beginning to unravel the Proust phenomenon?

    Mark Hughes

    2004-06-01

    Full Text Available The sense of smell is set apart from other sensory modalities. Odours possess the capacity to trigger immediately strong emotional memories. Moreover, odorous stimuli provide a higher degree of memory retention than other sensory stimuli. Odour perception, even in its most elemental form - olfaction - already involves limbic structures. This early involvement is not paralleled in other sensory modalities. Bearing in mind the considerable connectivity with limbic structures, and the fact that an activation of the amygdala is capable of instantaneously evoking emotions and facilitating the encoding of memories, it is unsurprising that the sense of smell has its characteristic nature. The aim of this review is to analyse current understanding of higher olfactory information processing as it relates to the ability of odours to spontaneously cue highly vivid, affectively toned, and often very old autobiographical memories (episodes known anecdotally as Proust phenomena. Particular emphasis is placed on the diversity of functions attributed to the amygdala. Its role in modulating the encoding and retrieval of long-term memory is investigated with reference to lesion, electrophysiological, immediate early gene, and functional imaging studies in both rodents and humans. Additionally, the influence of hormonal modulation and the adrenergic system on emotional memory storage is outlined. I finish by proposing a schematic of some of the critical neural pathways that underlie the odour-associated encoding and retrieval of emotionally toned autobiographical memories.

  8. 果蝇长时程记忆缺陷型突变体的鉴定%Identifying Furrowed Mutant in Drosophila with Long-term Memory Deficience

    王世清; 孙侃; 帅祎春; 王连章; 钟毅

    2012-01-01

    长时程记忆作为依赖蛋白合成的记忆组分,对于了解高等认知活动的分子机制有着重要意义.与此同时,细胞粘连分子作为影响突触可塑性的重要因子在学习与记忆研究领域也日益得到重视.为探索作用于长时程记忆的细胞粘连分子,利用P因子在果蝇基因组随机插入制造突变体,并通过大规模行为筛选得到了一个可能的长时程记忆突变体RUO.测序结果表明,突变体RUO的P因子位于果蝇中selectin超家族对应的furrowed同源基因功能片段和未知功能的CG1806基因编码片段之间,且更靠近furrowed片段.RT-PCR结果和互补遗传学实验均表明,突变体RUO主要影响furrowed基因的表达.为了进一步确认furrowed基因与长时程记忆的相关性,引入已知的furrowed基因突变体fw1.结果表明,fw1同样具有长时程记忆缺陷,同时具备正常的学习能力.荧光共聚焦扫描成像显示,该基因特异性的表达在果蝇大脑两个对称的未知神经元中.此项工作不仅证明了furrowed基因在果蝇长时程记忆中的重要作用,而且在解剖学上揭示了果蝇神经系统中可能参与长时程记忆形成的新的神经元.%Long-term memory related protein synthesis is a significant aspect for understanding of advanced cognitive behavior. Exploration of the relationship between long-term memory and adhesion molecules helped to link synaptic plasticity change with behavior modification. To discover novel adhesion molecules participating memory formation, we screened for defective long-term memory mutants in Drosophila of P-element inserted stocks, and obtained one defective mutant RUO. DNA sequencing and RT-PCR showed that the P-element in RUO mutant only disrupted the expression of the protein furrowed, an adhesion molecule of selectin superfamily. Both RUO mutant and an existed furrow mutant fw1 were observed defective for long-term memory in behavior experiments, but with normal aversive

  9. FXR1P Limits Long-Term Memory, Long-Lasting Synaptic Potentiation, and De Novo GluA2 Translation

    Denise Cook

    2014-11-01

    Full Text Available Translational control of mRNAs allows for rapid and selective changes in synaptic protein expression that are required for long-lasting plasticity and memory formation in the brain. Fragile X Related Protein 1 (FXR1P is an RNA-binding protein that controls mRNA translation in nonneuronal cells and colocalizes with translational machinery in neurons. However, its neuronal mRNA targets and role in the brain are unknown. Here, we demonstrate that removal of FXR1P from the forebrain of postnatal mice selectively enhances long-term storage of spatial memories, hippocampal late-phase long-term potentiation (L-LTP, and de novo GluA2 synthesis. Furthermore, FXR1P binds specifically to the 5′ UTR of GluA2 mRNA to repress translation and limit the amount of GluA2 that is incorporated at potentiated synapses. This study uncovers a mechanism for regulating long-lasting synaptic plasticity and spatial memory formation and reveals an unexpected divergent role of FXR1P among Fragile X proteins in brain plasticity.

  10. Chelation of hippocampal zinc enhances long-term potentiation and synaptic tagging/capture in CA1 pyramidal neurons of aged rats: implications to aging and memory.

    Shetty, Mahesh Shivarama; Sharma, Mahima; Sajikumar, Sreedharan

    2017-02-01

    Aging is associated with decline in cognitive functions, prominently in the memory consolidation and association capabilities. Hippocampus plays a crucial role in the formation and maintenance of long-term associative memories, and a significant body of evidence shows that impairments in hippocampal function correlate with aging-related memory loss. A number of studies have implicated alterations in hippocampal synaptic plasticity, such as long-term potentiation (LTP), in age-related cognitive decline although exact mechanisms underlying are not completely clear. Zinc deficiency and the resultant adverse effects on cognition have been well studied. However, the role of excess of zinc in synaptic plasticity, especially in aging, is not addressed well. Here, we have investigated the hippocampal zinc levels and the impairments in synaptic plasticity, such as LTP and synaptic tagging and capture (STC), in the CA1 region of acute hippocampal slices from 82- to 84-week-old male Wistar rats. We report increased zinc levels in the hippocampus of aged rats and also deficits in the tetani-induced and dopaminergic agonist-induced late-LTP and STC. The observed deficits in synaptic plasticity were restored upon chelation of zinc using a cell-permeable chelator. These data suggest that functional plasticity and associativity can be successfully established in aged neural networks by chelating zinc with cell-permeable chelating agents.

  11. Differential requirements of hippocampal de novo protein and mRNA synthesis in two long-term spatial memory tests: Spontaneous place recognition and delay-interposed radial maze performance in rats.

    Ozawa, Takaaki; Yamada, Kazuo; Ichitani, Yukio

    2017-01-01

    Hippocampal de novo mRNA and protein synthesis has been suggested to be critical for long-term spatial memory. However, its requirement in each memory process (i.e. encoding, consolidation and retrieval) and the differences in the roles of de novo mRNA and protein synthesis in different situations where spatial memory is tested have not been thoroughly investigated. To address these questions, we examined the effects of hippocampal administration of the protein synthesis inhibitors, anisomycin (ANI) and emetine (EME), as well as that of an mRNA synthesis inhibitor, 5,6-dichlorobenzimidazole 1-β-D-ribofuranoside (DRB), on rat performance in two long-term spatial memory tests. In a spontaneous place recognition test with a 6 h delay, ANI, administered either before or immediately after the sample phase, but not before the test phase, eliminated the exploratory preference for the object in a novel place. This amnesic effect was replicated by both EME and DRB. In a 6 h delay-interposed radial maze task, however, administering ANI before the first-half and before the second-half, but not immediately or 2 h after the first-half, impaired performance in the second-half. This disruptive effect of ANI was successfully replicated by EME. However, DRB administered before the first-half performance did not impair the second-half performance, while it did impair it if injected before the second-half. None of these drugs caused amnesic effects during the short (5 min)/non-delayed conditions in either tests. These results suggest that 1) hippocampal protein synthesis is required for the consolidation of spatial memory, while mRNA synthesis is not necessarily required, and 2) hippocampal mRNA and protein synthesis requirement for spatial memory retrieval depends on the types of memory tested, probably because their demands are different.

  12. Differential requirements of hippocampal de novo protein and mRNA synthesis in two long-term spatial memory tests: Spontaneous place recognition and delay-interposed radial maze performance in rats

    Ozawa, Takaaki; Yamada, Kazuo; Ichitani, Yukio

    2017-01-01

    Hippocampal de novo mRNA and protein synthesis has been suggested to be critical for long-term spatial memory. However, its requirement in each memory process (i.e. encoding, consolidation and retrieval) and the differences in the roles of de novo mRNA and protein synthesis in different situations where spatial memory is tested have not been thoroughly investigated. To address these questions, we examined the effects of hippocampal administration of the protein synthesis inhibitors, anisomycin (ANI) and emetine (EME), as well as that of an mRNA synthesis inhibitor, 5,6-dichlorobenzimidazole 1-β-D-ribofuranoside (DRB), on rat performance in two long-term spatial memory tests. In a spontaneous place recognition test with a 6 h delay, ANI, administered either before or immediately after the sample phase, but not before the test phase, eliminated the exploratory preference for the object in a novel place. This amnesic effect was replicated by both EME and DRB. In a 6 h delay-interposed radial maze task, however, administering ANI before the first-half and before the second-half, but not immediately or 2 h after the first-half, impaired performance in the second-half. This disruptive effect of ANI was successfully replicated by EME. However, DRB administered before the first-half performance did not impair the second-half performance, while it did impair it if injected before the second-half. None of these drugs caused amnesic effects during the short (5 min)/non-delayed conditions in either tests. These results suggest that 1) hippocampal protein synthesis is required for the consolidation of spatial memory, while mRNA synthesis is not necessarily required, and 2) hippocampal mRNA and protein synthesis requirement for spatial memory retrieval depends on the types of memory tested, probably because their demands are different. PMID:28178292

  13. Microstructure and diffraction pattern changes resulted from long-term aging of martensite CuZnAlMnNi shape memory alloy

    2002-01-01

    Microstructures of a CuZnAlMnNi shape memory alloy in the as-quenched and long-term aged conditions were investigated by transmission electron microscopy. Aged for one year in martensite phase, an equilibrium (-phase with fcc structure was observed in the M18R martensite matrix, accompanied by the appearance of a novel diffraction pattern. By analysis, it was suggested that the novel pattern results from the (-phase and the martensite matrix remaining in seven fine plates which produce intense secondary diffraction effect when the diffraction beams enter from one phase into another.

  14. The Effect of Synchronized Forced Running with Chronic Stress on Short, Mid and Long- term Memory in Rats

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

    2012-01-01

    Purpose Impairment of learning and memory processes has been demonstrated by many studies using different stressors. Other reports suggested that exercise has a powerful behavioral intervention to improve cognitive function and brain health. In this research, we investigated protective effects of treadmill running on chronic stress–induced memory deficit in rats. Methods Fifty male Wistar rats were randomly divided into five groups (n=10) as follows: Control (Co), Sham (Sh), Stress (St), Exer...

  15. An exemplar-familiarity model predicts short-term and long-term probe recognition across diverse forms of memory search.

    Nosofsky, Robert M; Cox, Gregory E; Cao, Rui; Shiffrin, Richard M

    2014-11-01

    Experiments were conducted to test a modern exemplar-familiarity model on its ability to account for both short-term and long-term probe recognition within the same memory-search paradigm. Also, making connections to the literature on attention and visual search, the model was used to interpret differences in probe-recognition performance across diverse conditions that manipulated relations between targets and foils across trials. Subjects saw lists of from 1 to 16 items followed by a single item recognition probe. In a varied-mapping condition, targets and foils could switch roles across trials; in a consistent-mapping condition, targets and foils never switched roles; and in an all-new condition, on each trial a completely new set of items formed the memory set. In the varied-mapping and all-new conditions, mean correct response times (RTs) and error proportions were curvilinear increasing functions of memory set size, with the RT results closely resembling ones from hybrid visual-memory search experiments reported by Wolfe (2012). In the consistent-mapping condition, new-probe RTs were invariant with set size, whereas old-probe RTs increased slightly with increasing study-test lag. With appropriate choice of psychologically interpretable free parameters, the model accounted well for the complete set of results. The work provides support for the hypothesis that a common set of processes involving exemplar-based familiarity may govern long-term and short-term probe recognition across wide varieties of memory- search conditions.

  16. Relative Ease in Creating Detailed Orthographic Representations Contrasted with Severe Difficulties to Maintain Them in Long-term Memory Among Dyslexic Children.

    Binamé, Florence; Danzio, Sophie; Poncelet, Martine

    2015-11-01

    Most research into orthographic learning abilities has been conducted in English with typically developing children using reading-based tasks. In the present study, we examined the abilities of French-speaking children with dyslexia to create novel orthographic representations for subsequent use in spelling and to maintain them in long-term memory. Their performance was compared with that of chronological age (CA)-matched and reading age (RA)-matched control children. We used an experimental task designed to provide optimal learning conditions (i.e. 10 spelling practice trials) ensuring the short-term acquisition of the spelling of the target orthographic word forms. After a 1-week delay, the long-term retention of the targets was assessed by a spelling post-test. Analysis of the results revealed that, in the short term, children with dyslexia learned the novel orthographic word forms well, only differing from both CA and RA controls on the initial decoding of the targets and from CA controls on the first two practice trials. In contrast, a dramatic drop was observed in their long-term retention relative to CA and RA controls. These results support the suggestion of the self-teaching hypothesis (Share, 1995) that initial errors in the decoding and spelling of unfamiliar words may hinder the establishment of fully specified novel orthographic representations.

  17. A model of long-term memory storage in the cerebellar cortex: a possible role for plasticity at parallel fiber synapses onto stellate/basket interneurons.

    Kenyon, G T

    1997-12-09

    By evoking changes in climbing fiber activity, movement errors are thought to modify synapses from parallel fibers onto Purkinje cells (pf*Pkj) so as to improve subsequent motor performance. Theoretical arguments suggest there is an intrinsic tradeoff, however, between motor adaptation and long-term storage. Assuming a baseline rate of motor errors is always present, then repeated performance of any learned movement will generate a series of climbing fiber-mediated corrections. By reshuffling the synaptic weights responsible for any given movement, such corrections will degrade the memories for other learned movements stored in overlapping sets of synapses. The present paper shows that long-term storage can be accomplished by a second site of plasticity at synapses from parallel fibers onto stellate/basket interneurons (pf*St/Bk). Plasticity at pf*St/Bk synapses can be insulated from ongoing fluctuations in climbing fiber activity by assuming that changes in pf*St/Bk synapses occur only after changes in pf*Pkj synapses have built up to a threshold level. Although climbing fiber-dependent plasticity at pf*Pkj synapses allows for the exploration of novel motor strategies in response to changing environmental conditions, plasticity at pf*St/Bk synapses transfers successful strategies to stable long-term storage. To quantify this hypothesis, both sites of plasticity are incorporated into a dynamical model of the cerebellar cortex and its interactions with the inferior olive. When used to simulate idealized motor conditioning trials, the model predicts that plasticity develops first at pf*Pkj synapses, but with additional training is transferred to pf*St/Bk synapses for long-term storage.

  18. Differential effects of spaced vs. massed training in long-term object-identity and object-location recognition memory.

    Bello-Medina, Paola C; Sánchez-Carrasco, Livia; González-Ornelas, Nadia R; Jeffery, Kathryn J; Ramírez-Amaya, Víctor

    2013-08-01

    Here we tested whether the well-known superiority of spaced training over massed training is equally evident in both object identity and object location recognition memory. We trained animals with objects placed in a variable or in a fixed location to produce a location-independent object identity memory or a location-dependent object representation. The training consisted of 5 trials that occurred either on one day (Massed) or over the course of 5 consecutive days (Spaced). The memory test was done in independent groups of animals either 24h or 7 days after the last training trial. In each test the animals were exposed to either a novel object, when trained with the objects in variable locations, or to a familiar object in a novel location, when trained with objects in fixed locations. The difference in time spent exploring the changed versus the familiar objects was used as a measure of recognition memory. For the object-identity-trained animals, spaced training produced clear evidence of recognition memory after both 24h and 7 days, but massed-training animals showed it only after 24h. In contrast, for the object-location-trained animals, recognition memory was evident after both retention intervals and with both training procedures. When objects were placed in variable locations for the two types of training and the test was done with a brand-new location, only the spaced-training animals showed recognition at 24h, but surprisingly, after 7 days, animals trained using both procedures were able to recognize the change, suggesting a post-training consolidation process. We suggest that the two training procedures trigger different neural mechanisms that may differ in the two segregated streams that process object information and that may consolidate differently.

  19. Post-training Activation of Rac1 in the Basolateral Amygdala Is Required for the Formation of both Short-term and Long-term Auditory Fear Memory

    Qinqin eGao

    2015-11-01

    Full Text Available Rac1, a member of the Rho family of small GTPases, is crucial for morphological changes of the mature neuronal synapse including spine formation and activity-dependent spine enlargement, while its role in the formation of associated memories, such as conditioned fear memory, is not clear. Here we report that selective deletion of Rac1 in excitatory neurons, but not in parvalbumin inhibitory neurons, impaired short- and long-term memories (STM and LTM of fear conditioning. Conditional knockout of Rac1 before associative fear training in the basolateral amygdala (BLA, a key area for fear memory acquisition and storage, impaired fear memory. The expression of dominant-negative mutant of Rac1, or infusion of Rac1 inhibitor NSC23766 into BLA blocked both STM and LTM of fear conditioning. Furthermore, selective inhibition of Rac1 activation in BLA immediately following fear conditioning impaired STM, demonstrating that fear conditioning-induced Rac1 activation in BLA plays a critical role in the formation of both STM and LTM of conditioned fear.

  20. Changes in heart rate variability are associated with expression of short-term and long-term contextual and cued fear memories.

    Jun Liu

    Full Text Available Heart physiology is a highly useful indicator for measuring not only physical states, but also emotional changes in animals. Yet changes of heart rate variability during fear conditioning have not been systematically studied in mice. Here, we investigated changes in heart rate and heart rate variability in both short-term and long-term contextual and cued fear conditioning. We found that while fear conditioning could increase heart rate, the most significant change was the reduction in heart rate variability which could be further divided into two distinct stages: a highly rhythmic phase (stage-I and a more variable phase (stage-II. We showed that the time duration of the stage-I rhythmic phase were sensitive enough to reflect the transition from short-term to long-term fear memories. Moreover, it could also detect fear extinction effect during the repeated tone recall. These results suggest that heart rate variability is a valuable physiological indicator for sensitively measuring the consolidation and expression of fear memories in mice.

  1. Changes in heart rate variability are associated with expression of short-term and long-term contextual and cued fear memories.

    Liu, Jun; Wei, Wei; Kuang, Hui; Zhao, Fang; Tsien, Joe Z

    2013-01-01

    Heart physiology is a highly useful indicator for measuring not only physical states, but also emotional changes in animals. Yet changes of heart rate variability during fear conditioning have not been systematically studied in mice. Here, we investigated changes in heart rate and heart rate variability in both short-term and long-term contextual and cued fear conditioning. We found that while fear conditioning could increase heart rate, the most significant change was the reduction in heart rate variability which could be further divided into two distinct stages: a highly rhythmic phase (stage-I) and a more variable phase (stage-II). We showed that the time duration of the stage-I rhythmic phase were sensitive enough to reflect the transition from short-term to long-term fear memories. Moreover, it could also detect fear extinction effect during the repeated tone recall. These results suggest that heart rate variability is a valuable physiological indicator for sensitively measuring the consolidation and expression of fear memories in mice.

  2. Improvement in Long-Term Memory following Chronic Administration of Eryngium planum Root Extract in Scopolamine Model: Behavioral and Molecular Study

    Marcin Ozarowski

    2015-01-01

    Full Text Available Eryngium planum L. (EP is as a rare medicinal plant with a lot of potentials as pharmaceutical crops. The aim of our study was to assess the effect of subchronic (28-fold administration of a 70% ethanol extract of EP roots (200 mg/kg, p.o. on behavioral and cognitive responses in Wistar rats linked with acetylcholinesterase (AChE, butyrylcholinesterase (BuChE, and beta-secretase (BACE-1 mRNA levels and AChE and BuChE activities in the hippocampus and frontal cortex. On the last day of experiment, 30 min after the last dose of EP or Huperzine A (HU, scopolamine (SC was given at a dose of 0.5 mg/kg b.w. intraperitoneally. The results of a passive avoidance test showed an improvement in long-term memory produced by the EP extract in both scopolamine-induced rats and control group. EP caused an insignificant inhibition of AChE and BuChE activities in the frontal cortex and the hippocampus. EP decreased mRNA AChE, BuChE, and BACE-1 levels, especially in the cortex. Our results suggest that the EP extract led to the improvement of the long-term memory in rats coupled with total saponin content. The mechanism of EP action is probably complicated, since HPLC-MS analysis showed 64 chemical compounds (phenolics, saponins in the extract of EP roots.

  3. Long-term treadmill exercise improves spatial memory of male APPswe/PS1dE9 mice by regulation of BDNF expression and microglia activation.

    Xiong, J Y; Li, S C; Sun, Y X; Zhang, X S; Dong, Z Z; Zhong, P; Sun, X R

    2015-11-01

    Increasing evidence suggests that physical activity could delay or attenuate the symptoms of Alzheimer's disease (AD). But the underlying mechanisms are still not fully understood. To investigate the effect of long-term treadmill exercise on the spatial memory of AD mice and the possible role of β-amyloid, brain-derived neurotrophic factor (BDNF) and microglia in the effect, male APPswe/PS1dE9 AD mice aged 4 months were subjected to treadmill exercise for 5 months with 6 sessions per week and gradually increased load. A Morris water maze was used to evaluate the spatial memory. Expression levels of β-amyloid, BDNF and Iba-1 (a microglia marker) in brain tissue were detected by immunohistochemistry. Sedentary AD mice and wildtype C57BL/6J mice served as controls. The results showed that 5-month treadmill exercise significantly decreased the escape latencies (P memory of the AD mice in the water maze test. Meanwhile, treadmill exercise significantly increased the number of BDNF-positive cells and decreased the ratios of activated microglia in both the cerebral cortex and the hippocampus. However, treadmill exercise did not significantly alleviate the accumulation of β-amyloid in either the cerebral cortex or the hippocampus of the AD mice (P > 0.05). The study suggested that long-term treadmill exercise could improve the spatial memory of the male APPswe/PS1dE9 AD mice. The increase in BDNF-positive cells and decrease in activated microglia might underpin the beneficial effect.

  4. Pre-learning stress differentially affects long-term memory for emotional words, depending on temporal proximity to the learning experience.

    Zoladz, Phillip R; Clark, Brianne; Warnecke, Ashlee; Smith, Lindsay; Tabar, Jennifer; Talbot, Jeffery N

    2011-07-06

    Stress exerts a profound, yet complex, influence on learning and memory and can enhance, impair or have no effect on these processes. Here, we have examined how the administration of stress at different times before learning affects long-term (24-hr) memory for neutral and emotional information. Participants submerged their dominant hand into a bath of ice cold water (Stress) or into a bath of warm water (No stress) for 3 min. Either immediately (Exp. 1) or 30 min (Exp. 2) after the water bath manipulation, participants were presented with a list of 30 words varying in emotional valence. The next day, participants' memory for the word list was assessed via free recall and recognition tests. In both experiments, stressed participants exhibited greater blood pressure, salivary cortisol levels, and subjective pain and stress ratings than non-stressed participants in response to the water bath manipulation. Stress applied immediately prior to learning (Exp. 1) enhanced the recognition of positive words, while stress applied 30 min prior to learning (Exp. 2) impaired free recall of negative words. Participants' recognition of positive words in Experiment 1 was positively associated with their heart rate responses to the water bath manipulation, while participants' free recall of negative words in Experiment 2 was negatively associated with their blood pressure and cortisol responses to the water bath manipulation. These findings indicate that the differential effects of pre-learning stress on long-term memory may depend on the temporal proximity of the stressor to the learning experience and the emotional nature of the to-be-learned information.

  5. Leishmania braziliensis-reactive T cells are down-regulated in long-term cured cutaneous Leishmaniasis, but the renewal capacity of T effector memory compartments is preserved.

    Regina Pereira-Carvalho

    Full Text Available Leishmania (Viannia braziliensis control and tissue damage relate to the effector immune response, which in turn affects clinical outcome. Leishmania reactive CD4(+ and CD8(+ T cells are expanded in long-term healed cutaneous leishmaniasis (hCL patients but their functional characteristics remain to be determined. This study investigates antigen-specific recall in long-term healed CL caused by L. braziliensis infection. Healed CL subjects were grouped according to the time elapsed since the end of therapy: less than two years and two to five years. Activation phenotype (CD69(+ or CD25(+ and subpopulations of memory T cell phenotypes [central memory (Tcm: CD45RO(+ CCR7(+ or effector memory (Tem: CD45RO(+ CCR7(-] were quantified in ex vivo blood mononuclear cells and after Leishmania antigens stimuli. A reduction in the percentage of activated Leishmania-responder CD4(+ and CD8(+ T cells in hCL was associated with the time elapsed since clinical cure. Percentage of CD69(+ in TCD4(+ and TCD8(+ cells were negatively correlated with IL-10 levels. Ex vivo analyses showed contracted Tem CD4(+ and Tem CD8(+ compartments from hCL with long time elapsed since clinical cure, although renewal of these compartments was observed following in vitro exposure to leishmanial stimuli. Our results show that healed L. braziliensis infected patients exhibit a recall response to Leishmania antigens with evident expansion of effector memory T cells. Regulated leishmanial-specific response seems to emerge only about two years after initial contact with the parasite antigens.

  6. The Ubiquitin-Specific Protease 14 (USP14) Is a Critical Regulator of Long-Term Memory Formation

    Jarome, Timothy J.; Kwapis, Janine L.; Hallengren, Jada J.; Wilson, Scott M.; Helmstetter, Fred J.

    2014-01-01

    Numerous studies have suggested a role for ubiquitin-proteasome-mediated protein degradation in learning-dependent synaptic plasticity; however, very little is known about how protein degradation is regulated at the level of the proteasome during memory formation. The ubiquitin-specific protease 14 (USP14) is a proteasomal deubiquitinating enzyme…

  7. LONG-TERM EFFICACY AND IMMUNOLOGICAL MEMORY OF PLASMA-DERIVED HEPATITIS B VACCINE 11 YEARS AFTER INITIAL INOCULATION

    2000-01-01

    Objective To assess the efficacy and the immunological memory of plasma-derived hepatitis B vac- cine 11 years after the initial inoculation. Methods A randomized, double-blind and placebo-controlled trial design was used. Results The immunogenicity and protection rate of the vaccine were good 1 1 years after vaccination, how- ever, from 9 to 11 years after vaccination, the perscn year HBV infection rate showed no noticeable difference be- tween the vaccine group and placebo-controls. Furthermore, the immunological memory remained 11 years after in- oculation, but was significantly lower than that observed in the past 10 years. Conclusion Vaccine protection wanes over the years. More information is needed to define the appropriate time for vaccine booster doses.

  8. Long-term memory traces for familiar spoken words in tonal languages as revealed by the Mismatch Negativity

    Naiphinich Kotchabhakdi

    2004-11-01

    Full Text Available Mismatch negativity (MMN, a primary response to an acoustic change and an index of sensory memory, was used to investigate the processing of the discrimination between familiar and unfamiliar Consonant-Vowel (CV speech contrasts. The MMN was elicited by rare familiar words presented among repetitive unfamiliar words. Phonetic and phonological contrasts were identical in all conditions. MMN elicited by the familiar word deviant was larger than that elicited by the unfamiliar word deviant. The presence of syllable contrast did significantly alter the word-elicited MMN in amplitude and scalp voltage field distribution. Thus, our results indicate the existence of word-related MMN enhancement largely independent of the word status of the standard stimulus. This enhancement may reflect the presence of a longterm memory trace for familiar spoken words in tonal languages.

  9. Disruption of long-term alcohol-related memory reconsolidation: Role of β-adrenoceptors and NMDA receptors

    Jelte A Wouda

    2010-11-01

    Full Text Available Disrupting reconsolidation of drug-related memories may be effective in reducing the incidence of relapse. In the current study we examine whether alcohol- related memories are prone to disruption by the β -adrenergicreceptor antagonist propranolol (10 mg/kg and the NMDA receptor antagonist MK801 (0.1 mg/kg following their reactivation. In operant chambers, male Wistar rats were trained to self-administer a 12% alcohol solution. After 3 weeks of abstinence, the animals were placed in the self-administration cages and were reexposed to the alcohol-associated cues for a 20-min retrieval period, immediately followed by a systemic injection of either propranolol, MK801 or saline. Rats were tested for cue-induced alcohol seeking on the following day. Retrieval session, injection and test were repeated on 2 further occasions at weekly intervals. Both propranolol and MK801 administration upon reactivation did not reduce alcohol seeking after the first reactivation test. However, a significant reduction of alcohol seeking was observed over three post-training tests in propranolol treated animals, and MK801 treated animals showed a strong tendency towards reduced alcohol seeking (p=0.06. Our data indicate that reconsolidation of alcohol-related memories can be disrupted after a long post-training interval and that particularly β-adrenergic receptors may represent novel targets for pharmacotherapy of alcoholism, in combination with cue-exposure therapies.

  10. Caffeine suppresses exercise-enhanced long-term and location memory in middle-aged rats: Involvement of hippocampal Akt and CREB signaling.

    Cechella, José L; Leite, Marlon R; da Rocha, Juliana T; Dobrachinski, Fernando; Gai, Bibiana M; Soares, Félix A A; Bresciani, Guilherme; Royes, Luiz F F; Zeni, Gilson

    2014-11-05

    The cognitive function decline is closely related with brain changes generated by age. The ability of caffeine and exercise to prevent memory impairment has been reported in animal models and humans. The purpose of the present study was to investigate whether swimming exercise and caffeine administration enhance memory in middle-aged Wistar rats. Male Wistar rats (18months) received caffeine at a dose of 30mg/kg, 5days per week by a period of 4weeks. Animals were subjected to swimming training with a workload (3% of body weight, 20min per day for 4weeks). After 4weeks, the object recognition test (ORT) and the object location test (OLT) were performed. The results of this study demonstrated that caffeine suppressed exercise-enhanced long-term (ORT) and spatial (OLT) memory in middle-aged and this effect may be related to a decrease in hippocampal p-CREB signaling. This study also provided evidence that the effects of this protocol on memory were not accompanied by alterations in the levels of activated Akt. The [(3)H] glutamate uptake was reduced in hippocampus of rats administered with caffeine and submitted to swimming protocol.

  11. Mice deficient for striatal Vesicular Acetylcholine Transporter (VAChT) display impaired short-term but normal long-term object recognition memory.

    Palmer, Daniel; Creighton, Samantha; Prado, Vania F; Prado, Marco A M; Choleris, Elena; Winters, Boyer D

    2016-09-15

    Substantial evidence implicates Acetylcholine (ACh) in the acquisition of object memories. While most research has focused on the role of the cholinergic basal forebrain and its cortical targets, there are additional cholinergic networks that may contribute to object recognition. The striatum contains an independent cholinergic network comprised of interneurons. In the current study, we investigated the role of this cholinergic signalling in object recognition using mice deficient for Vesicular Acetylcholine Transporter (VAChT) within interneurons of the striatum. We tested whether these striatal VAChT(D2-Cre-flox/flox) mice would display normal short-term (5 or 15min retention delay) and long-term (3h retention delay) object recognition memory. In a home cage object recognition task, male and female VAChT(D2-Cre-flox/flox) mice were impaired selectively with a 15min retention delay. When tested on an object location task, VAChT(D2-Cre-flox/flox) mice displayed intact spatial memory. Finally, when object recognition was tested in a Y-shaped apparatus, designed to minimize the influence of spatial and contextual cues, only females displayed impaired recognition with a 5min retention delay, but when males were challenged with a 15min retention delay, they were also impaired; neither males nor females were impaired with the 3h delay. The pattern of results suggests that striatal cholinergic transmission plays a role in the short-term memory for object features, but not spatial location.

  12. The Screening of Genes Sensitive to Long-Term, Low-Level Microwave Exposure and Bioinformatic Analysis of Potential Correlations to Learning and Memory

    ZHAO Ya Li; LI Ying Xian; MA Hong Bo; LI Dong; LI Hai Liang; JIANG Rui; KAN Guang Han; YANG Zhen Zhong; HUANG Zeng Xin

    2015-01-01

    Objective To gain a better understanding of gene expression changes in the brain following microwave exposure in mice. This study hopes to reveal mechanisms contributing to microwave-induced learning and memory dysfunction. Methods Mice were exposed to whole body 2100 MHz microwaves with specific absorption rates (SARs) of 0.45 W/kg, 1.8 W/kg, and 3.6 W/kg for 1 hour daily for 8 weeks. Differentially expressing genes in the brains were screened using high-density oligonucleotide arrays, with genes showing more significant differences further confirmed by RT-PCR. Results The gene chip results demonstrated that 41 genes (0.45 W/kg group), 29 genes (1.8 W/kg group), and 219 genes (3.6 W/kg group) were differentially expressed. GO analysis revealed that these differentially expressed genes were primarily involved in metabolic processes, cellular metabolic processes, regulation of biological processes, macromolecular metabolic processes, biosynthetic processes, cellular protein metabolic processes, transport, developmental processes, cellular component organization, etc. KEGG pathway analysis showed that these genes are mainly involved in pathways related to ribosome, Alzheimer's disease, Parkinson's disease, long-term potentiation, Huntington's disease, and Neurotrophin signaling. Construction of a protein interaction network identified several important regulatory genes including synbindin (sbdn), Crystallin (CryaB), PPP1CA, Ywhaq, Psap, Psmb1, Pcbp2, etc., which play important roles in the processes of learning and memory. Conclusion Long-term, low-level microwave exposure may inhibit learning and memory by affecting protein and energy metabolic processes and signaling pathways relating to neurological functions or diseases.

  13. Long-term anti-HBs antibody persistence and immune memory in children and adolescents who received routine childhood hepatitis B vaccination.

    Behre, Ulrich; Bleckmann, Gerhard; Crasta, Priya Diana; Leyssen, Maarten; Messier, Marc; Jacquet, Jeanne-Marie; Hardt, Karin

    2012-06-01

    This paper presents data from two studies that evaluated 5-y and 10-y persistence of antibodies against hepatitis B (HBV) surface antigen (anti-HBs) and immune response to an HBV vaccine challenge in children and adolescents who had received three doses of a HBV vaccine in infancy as part of routine clinical practice [NCT00519649/NCT00984139]. Anti-HBs antibody concentrations ≥ 10 mIU/ml persisted in 83.3% (95% confidence interval [CI]: 78.5–87.5) and 78.3% (95% CI: 73.1–83.0) of subjects aged 7–8 y and 12–13 y, respectively 5–10 y after infant vaccination. One month postchallenge dose, 98.2% (95% CI: 95.9–99.4) and 93.7% (95% CI: 90.2–96.2) of subjects in the two age groups, respectively had anti-HBs antibody concentrations ≥ 100 mIU/ml. Overall, 99.6% (95% CI: 98–100) and 97.2% (95% CI: 94.5–98.8) of subjects aged 7–8 y and 12–13 y mounted an anamnestic response to the HBV challenge dose, which was well-tolerated. Healthy children aged 7–8 y and adolescents aged 12–13 y received three doses of a monovalent pediatric HBV vaccine (10 μg of HBsAg) before 18 mo of age. Serum samples collected before and one month post-HBV vaccine challenge dose were tested for anti-HBs antibody concentrations. Safety assessments were made for the HBV vaccine challenge dose. A three-dose childhood HBV immunization regimen induced persistence of antibodies against HBV infection for 10 y, up to adolescence. This vaccination regimen also conferred long-term immune memory against HBV as evidenced by the strong anamnestic response to the HBV vaccine challenge, despite waning anti-HBs antibody levels.

  14. Long-term resource variation and group size: A large-sample field test of the Resource Dispersion Hypothesis

    Morecroft Michael D

    2001-07-01

    Full Text Available Abstract Background The Resource Dispersion Hypothesis (RDH proposes a mechanism for the passive formation of social groups where resources are dispersed, even in the absence of any benefits of group living per se. Despite supportive modelling, it lacks empirical testing. The RDH predicts that, rather than Territory Size (TS increasing monotonically with Group Size (GS to account for increasing metabolic needs, TS is constrained by the dispersion of resource patches, whereas GS is independently limited by their richness. We conducted multiple-year tests of these predictions using data from the long-term study of badgers Meles meles in Wytham Woods, England. The study has long failed to identify direct benefits from group living and, consequently, alternative explanations for their large group sizes have been sought. Results TS was not consistently related to resource dispersion, nor was GS consistently related to resource richness. Results differed according to data groupings and whether territories were mapped using minimum convex polygons or traditional methods. Habitats differed significantly in resource availability, but there was also evidence that food resources may be spatially aggregated within habitat types as well as between them. Conclusions This is, we believe, the largest ever test of the RDH and builds on the long-term project that initiated part of the thinking behind the hypothesis. Support for predictions were mixed and depended on year and the method used to map territory borders. We suggest that within-habitat patchiness, as well as model assumptions, should be further investigated for improved tests of the RDH in the future.

  15. Single fluoxetine treatment before but not after stress prevents stress-induced hippocampal long-term depression and spatial memory retrieval impairment in rats.

    Han, Huili; Dai, Chunfang; Dong, Zhifang

    2015-07-28

    A growing body of evidence has shown that chronic treatment with fluoxetine, a widely prescribed medication for treatment of depression, can affect synaptic plasticity in the adult central nervous system. However, it is not well understood whether acute fluoxetine influences synaptic plasticity, especially on hippocampal CA1 long-term depression (LTD), and if so, whether it subsequently impacts hippocampal-dependent spatial memory. Here, we reported that LTD facilitated by elevated-platform stress in hippocampal slices was completely prevented by fluoxetine administration (10 mg/kg, i.p.) 30 min before stress. The LTD was not, however, significantly inhibited by fluoxetine administration immediately after stress. Similarly, fluoxetine incubation (10 μM) during electrophysiological recordings also displayed no influence on the stress-facilitated LTD. In addition, behavioral results showed that a single fluoxetine treatment 30 min before but not after acute stress fully reversed the impairment of spatial memory retrieval in the Morris water maze paradigm. Taken together, these results suggest that acute fluoxetine treatment only before, but not after stress, can prevent hippocampal CA1 LTD and spatial memory retrieval impairment caused by behavioral stress in adult animals.

  16. The n-butanolic extract of Opuntia ficus-indica var. saboten enhances long-term memory in the passive avoidance task in mice.

    Kim, Jong Min; Kim, Dong Hyun; Park, Se Jin; Park, Dong Hyun; Jung, Seo Yun; Kim, Hyoung Ja; Lee, Yong Sup; Jin, Changbae; Ryu, Jong Hoon

    2010-08-16

    Opuntia ficus-indica var. saboten Makino (Cactaceae) is used to treat burns, edema, dyspepsia, and asthma in traditional medicine. The present study investigated the beneficial effects of the n-butanolic extract of O. ficus-indica var. saboten (BOF) on memory performance in mice and attempts to uncover the mechanisms underlying its action. Memory performance was assessed with the passive avoidance task, and western blotting and immunohistochemistry were used to measure changes in protein expression and cell survival. After the oral administration of BOF for 7 days, the latency time in the passive avoidance task was significantly increased relative to vehicle-treated controls (P<0.05). Western blotting revealed that the expression levels of brain-derived neurotrophic factor (BDNF), phosphorylated cAMP response element binding-protein (pCREB), and phosphorylated extracellular signal-regulated kinase (pERK) 1/2 were significantly increased in hippocampal tissue after 7 days of BOF administration (P<0.05). Doublecortin and 5-bromo-2-deoxyuridine immunostaining also revealed that BOF significantly enhanced the survival of immature neurons, but did not affect neuronal cell proliferation in the subgranular zone of the hippocampal dentate gyrus. These results suggest that the subchronic administration of BOF enhances long-term memory, and that this effect is partially mediated by ERK-CREB-BDNF signaling and the survival of immature neurons.

  17. A 72% error reduction scheme based on temperature acceleration for long-term data storage applications: Cold flash and millennium memories

    Yamazaki, Senju; Iwasaki, Tomoko Ogura; Hachiya, Shogo; Takahashi, Tomonori; Takeuchi, Ken

    2016-07-01

    A solid-state drive (SSD) with 1Xnm triple-level cell (TLC) NAND flash is proposed for low cost data storage applications with long-term data-retention requirements. Specifically, cold data storage requires 20 years data-retention with 100 write/erase (W/E) cycles, whereas digital archive storage requires 1000 years retention time with 1 W/E cycle. To achieve these requirements, a flexible-nLC scheme is proposed to improve the reliability of 1Xnm TLC NAND flash (Yamazaki et al., 2015). The proposed scheme combines two schemes, n-out-of-8 level cell (nLC) (Tanakamaru et al., 2014) and asymmetric coding (AC) (Tanakamaru et al., 2012) with the addition of a vertical flag. By measuring 1Xnm TLC NAND flash memory, the proposed scheme reduces errors by 72% and 69% for digital archive and cold flash respectively, compared to the conventional nLC scheme.

  18. Long-Term Electrophysiological and Behavioral Analysis on the Improvement of Visual Working Memory Load, Training Gains, and Transfer Benefits.

    Kuo, Ching-Chang; Zhang, Cheng; Rissman, Robert A; Chiu, Alan W L

    2014-05-01

    Recent evidence demonstrates that with training, one can enhance visual working memory (VWM) capacity and attention over time in the near transfer tasks. Not only do these studies reveal the characteristics of VWM load and the influences of training, they may also provide insights into developing effective rehabilitation for patients with VWM deficiencies. However, few studies have investigated VWM over extended periods of time and evaluated transfer benefits on non-trained tasks. Here, we combined behavioral and electroencephalographical approaches to investigate VWM load, training gains, and transfer benefits. Our results reveal that VWM capacity is directly correlated to the difference of event-related potential waveforms. In particular, the "magic number 4" can be observed through the contralateral delay amplitude and the average capacity is 3.25-item over 15 participants. Furthermore, our findings indicate that VWM capacity can be improved through training; and after training exercises, participants from the training group are able to dramatically improve their performance. Likewise, the training effects on non-trained tasks can also be observed at the 12th week after training. Therefore, we conclude that participants can benefit from training gains, and augmented VWM capacity sustained over long periods of time on specific variety of tasks.

  19. Learning-Induced Gene Expression in the Hippocampus Reveals a Role of Neuron -Astrocyte Metabolic Coupling in Long Term Memory

    Tadi, Monika

    2015-10-29

    We examined the expression of genes related to brain energy metabolism and particularly those encoding glia (astrocyte)-specific functions in the dorsal hippocampus subsequent to learning. Context-dependent avoidance behavior was tested in mice using the step-through Inhibitory Avoidance (IA) paradigm. Animals were sacrificed 3, 9, 24, or 72 hours after training or 3 hours after retention testing. The quantitative determination of mRNA levels revealed learning-induced changes in the expression of genes thought to be involved in astrocyte-neuron metabolic coupling in a time dependent manner. Twenty four hours following IA training, an enhanced gene expression was seen, particularly for genes encoding monocarboxylate transporters 1 and 4 (MCT1, MCT4), alpha2 subunit of the Na/K-ATPase and glucose transporter type 1. To assess the functional role for one of these genes in learning, we studied MCT1 deficient mice and found that they exhibit impaired memory in the inhibitory avoidance task. Together, these observations indicate that neuron-glia metabolic coupling undergoes metabolic adaptations following learning as indicated by the change in expression of key metabolic genes.

  20. The role of long-term familiarity and attentional maintenance in short-term memory for timbre.

    Siedenburg, Kai; McAdams, Stephen

    2017-04-01

    We study short-term recognition of timbre using familiar recorded tones from acoustic instruments and unfamiliar transformed tones that do not readily evoke sound-source categories. Participants indicated whether the timbre of a probe sound matched with one of three previously presented sounds (item recognition). In Exp. 1, musicians better recognised familiar acoustic compared to unfamiliar synthetic sounds, and this advantage was particularly large in the medial serial position. There was a strong correlation between correct rejection rate and the mean perceptual dissimilarity of the probe to the tones from the sequence. Exp. 2 compared musicians' and non-musicians' performance with concurrent articulatory suppression, visual interference, and with a silent control condition. Both suppression tasks disrupted performance by a similar margin, regardless of musical training of participants or type of sounds. Our results suggest that familiarity with sound source categories and attention play important roles in short-term memory for timbre, which rules out accounts solely based on sensory persistence.

  1. Learning-Induced Gene Expression in the Hippocampus Reveals a Role of Neuron -Astrocyte Metabolic Coupling in Long Term Memory.

    Monika Tadi

    Full Text Available We examined the expression of genes related to brain energy metabolism and particularly those encoding glia (astrocyte-specific functions in the dorsal hippocampus subsequent to learning. Context-dependent avoidance behavior was tested in mice using the step-through Inhibitory Avoidance (IA paradigm. Animals were sacrificed 3, 9, 24, or 72 hours after training or 3 hours after retention testing. The quantitative determination of mRNA levels revealed learning-induced changes in the expression of genes thought to be involved in astrocyte-neuron metabolic coupling in a time dependent manner. Twenty four hours following IA training, an enhanced gene expression was seen, particularly for genes encoding monocarboxylate transporters 1 and 4 (MCT1, MCT4, alpha2 subunit of the Na/K-ATPase and glucose transporter type 1. To assess the functional role for one of these genes in learning, we studied MCT1 deficient mice and found that they exhibit impaired memory in the inhibitory avoidance task. Together, these observations indicate that neuron-glia metabolic coupling undergoes metabolic adaptations following learning as indicated by the change in expression of key metabolic genes.

  2. Development of More Cost-Effective Methods for Long-Term Monitoring of Soil Vapor Intrusion to Indoor Air Using Quantitative Passive Diffusive-Adsorptive Sampling Techniques

    2015-05-01

    provide motivation for VI investigations. For sites where there is unacceptable VI, a long-term monitoring program may be required to demonstrate...samplers) because steel reinforcing bars were repeatedly encountered and eventually broke the teeth on the concrete hole- saw. The ATD, WMS, and Radiello...www.itrcweb.org/Documents/VI-1.pdf) ISO Indoor Ambient and Workplace Air – Sampling and Analysis of Volatile Compounds by Sorbent Tube/Thermal

  3. Significant long-term, but not short-term, hippocampal-dependent memory impairment in adult rats exposed to alcohol in early postnatal life.

    Goodfellow, Molly J; Lindquist, Derick H

    2014-09-01

    In rodents, ethanol exposure in early postnatal life is known to induce structural and functional impairments throughout the brain, including the hippocampus. Herein, rat pups were administered one of three ethanol doses over postnatal days (PD) 4-9, a period of brain development comparable to the third trimester of human pregnancy. As adults, control and ethanol rats were trained and tested in a variant of hippocampal-dependent one-trial context fear conditioning. In Experiment 1, subjects were placed into a novel context and presented with an immediate footshock (i.e., within ∼8 sec). When re-exposed to the same context 24 hr later low levels of conditioned freezing were observed. Context pre-exposure 24 hr prior to the immediate shock reversed the deficit in sham-intubated and unintubated control rats, enhancing freezing behavior during the context retention test. Even with context pre-exposure, however, significant dose-dependent reductions in contextual freezing were seen in ethanol rats. In Experiment 2, the interval between context pre-exposure and the immediate shock was shortened to 2 hr, in addition to the standard 24 hr. Ethanol rats trained with the 2 hr, but not 24 hr, interval displayed retention test freezing levels roughly equal to controls. Results suggest the ethanol rats can encode a short-term context memory and associate it with the aversive footshock 2 hr later. In the 24 hr ethanol rats the short-term context memory is poorly transferred or consolidated into long-term memory, we propose, impeding the memory's subsequent retrieval and association with shock.

  4. Armodafinil improves wakefulness and long-term episodic memory in nCPAP-adherent patients with excessive sleepiness associated with obstructive sleep apnea.

    Roth, Thomas; Rippon, Gregory A; Arora, Sanjay

    2008-03-01

    Residual excessive sleepiness (ES) and impaired cognition can occur despite effective and regular nasal continuous positive airway pressure (nCPAP) therapy in some patients with obstructive sleep apnea (OSA). A pooled analysis of two 12-week, randomized, double-blind studies in nCPAP-adherent patients with ES associated with OSA evaluated the effect of armodafinil on wakefulness and cognition. Three hundred and ninety-one patients received armodafinil (150 or 250 mg) and 260 patients received placebo once daily for 12 weeks. Efficacy assessments included the Maintenance of Wakefulness Test (MWT), Cognitive Drug Research cognitive performance battery, Epworth Sleepiness Scale, and Brief Fatigue Inventory. Adverse events were monitored. Armodafinil increased mean MWT sleep latency from baseline to final visit by 2.0 min vs a decrease of 1.5 min with placebo (P armodafinil significantly improved quality of episodic secondary memory (P Armodafinil did not adversely affect desired nighttime sleep, and nCPAP use remained high (approximately 7 h/night). Adjunct treatment with armodafinil significantly improved wakefulness, long-term memory, and patients' ability to engage in activities of daily living in nCPAP-adherent individuals with ES associated with OSA. Armodafinil also reduced patient-reported fatigue and was well tolerated.

  5. Gulf War agent exposure causes impairment of long-term memory formation and neuropathological changes in a mouse model of Gulf War Illness.

    Zuchra Zakirova

    Full Text Available Gulf War Illness (GWI is a chronic multisymptom illness with a central nervous system component such as memory deficits, neurological, and musculoskeletal problems. There are ample data that demonstrate that exposure to Gulf War (GW agents, such as pyridostigmine bromide (PB and pesticides such as permethrin (PER, were key contributors to the etiology of GWI post deployment to the Persian GW. In the current study, we examined the consequences of acute (10 days exposure to PB and PER in C57BL6 mice. Learning and memory tests were performed at 18 days and at 5 months post-exposure. We investigated the relationship between the cognitive phenotype and neuropathological changes at short and long-term time points post-exposure. No cognitive deficits were observed at the short-term time point, and only minor neuropathological changes were detected. However, cognitive deficits emerged at the later time point and were associated with increased astrogliosis and reduction of synaptophysin staining in the hippocampi and cerebral cortices of exposed mice, 5 months post exposure. In summary, our findings in this mouse model of GW agent exposure are consistent with some GWI symptom manifestations, including delayed onset of symptoms and CNS disturbances observed in GWI veterans.

  6. Students' Long-Term Memories from an Ecology Field Excursion: Retelling a Narrative as an Interplay between Implicit and Explicit Memories

    Stolpe, Karin; Bjorklund, Lars

    2013-01-01

    This study aims to investigate the science content remembered by biology students 6 and 12 months after an ecology excursion. The students' memories were tested during a stimulated recall interview. The authors identified three different types of memories: "recall," "recognition" and "narratives." The "dual…

  7. Fus1 KO mouse as a model of oxidative stress-mediated sporadic Alzheimer’s disease: circadian disruption and long-term spatial and olfactory memory impairments.

    Guillermo Coronas-Samano

    2016-11-01

    Full Text Available Insufficient advances in the development of effective therapeutic treatments of sporadic Alzheimer's Disease (sAD to date are largely due to the lack of sAD-relevant animal models. While the vast majority of models do recapitulate AD's hallmarks of plaques and tangles by virtue of tau and/or beta amyloid overexpression, these models do not reflect the fact that in sAD (unlike familial AD these genes are not risk factors per se and that other mechanisms like oxidative stress, metabolic dysregulation and inflammation play key roles in AD etiology. Here we characterize and propose the Fus1 KO mice that lack a mitochondrial protein Fus1/Tusc2 as a new sAD model. To establish sAD relevance, we assessed sAD related deficits in Fus1 KO and WT adult mice of 4-5 months old, the equivalent human age when the earliest cognitive and olfactory sAD symptoms arise. Fus1 KO mice showed oxidative stress (increased levels of ROS, decreased levels of PRDX1, disruption of metabolic homeostasis (decreased levels of ACC2, increased phosphorylation of AMPK, autophagy (decreased levels of LC3-II, PKC (decreased levels of RACK1 and calcium signaling (decreased levels of Calb2 in the olfactory bulb and/or hippocampus. Mice were behaviorally tested using objective and accurate video tracking (Noldus, in which Fus1 KO mice showed clear deficits in olfactory memory (decreased habituation/cross-habituation in the short and long term, olfactory guided navigation memory (inability to reduce their latency to find the hidden cookie, spatial memory (learning impairments on finding the platform in the Morris water maze and showed more sleep time during the diurnal cycle. Fus1 KO mice did not show clear deficits in olfactory perception (cross-habituation, association memory (passive avoidance or in species-typical behavior (nest building and no increased anxiety (open field, light-dark box or depression/anhedonia (sucrose preference at this relatively young age. These

  8. Effect of exposure conditions on the long-term dielectric properties of mortar samples containing ASR gel

    Hashemi, A.; Donnell, K. M.; Zoughi, R.; Rashidi, M.; Kurtis, K. E.

    2017-02-01

    Alkali-silica reaction (ASR) is a chemical reaction between alkalis present in portland cement and amorphous or otherwise disordered siliceous minerals in particular aggregates. Through this reaction, reactive silica binds with hydroxyl and alkali ions and forms a gel, known as ASR gel. Recently, microwave materials characterization techniques have shown great potential for detecting ASR in mortar. However, the comprehensive understanding of variables that affect the extent of ASR in mortar and their interaction with microwave signals, in particular the effect of environmental exposure conditions requires more investigations. Therefore, parameters related to these conditions must be considered when using microwave techniques for ASR detection and evaluation. In this paper, the effect of exposure conditions on ASR gel formation and microwave dielectric properties of mortar samples is investigated. To this end, extended measurements of the complex dielectric constants of three different sets of mortar samples are presented at S-band (2.6 - 3.95 GHz). The samples were cast with potentially reactive ASR-aggregates and subjected to different environmental conditions. The results show slightly different permittivities for the differently stored samples, potentially indicating different amount of ASR gel. This observation was corroborated through UV fluorescence microscopy, where different amounts of ASR gel were observed in the samples. Moreover, the results indicate that ASR gel evolution may be better tracked through loss factor measurements, while pre-existing-gel may be better detected through permittivity measurements.

  9. Effects of long-term environmental enrichment on anxiety, memory, hippocampal plasticity and overall brain gene expression in C57BL6 mice

    Melanie Hüttenrauch

    2016-08-01

    Full Text Available There is ample evidence that physical activity exerts positive effects on a variety of brain functions by facilitating neuroprotective processes and influencing neuroplasticity. Accordingly, numerous studies have shown that continuous exercise can successfully diminish or prevent the pathology of neurodegenerative diseases such as Alzheimer’s disease in transgenic mouse models. However, the long-term effect of physical activity on brain health of aging WT mice has not been studied in detail yet. Here, we show that prolonged physical and cognitive stimulation, mediated by an enriched environment (EE paradigm for a duration of eleven months, leads to reduced anxiety and improved spatial reference memory in C57BL6 wildtype (WT mice. While the number of CA1 pyramidal neurons remained unchanged between standard housed (SH and EE mice, the number of dentate gyrus (DG neurons, as well as the CA1 and DG volume were significantly increased in EE mice. A whole-brain deep sequencing transcriptome analysis, carried out to better understand the molecular mechanisms underlying the observed effects, revealed an up-regulation of a variety of genes upon EE, mainly associated with synaptic plasticity and transcription regulation. The present findings corroborate the impact of continuous physical activity as a potential prospective route in the prevention of age-related cognitive decline and neurodegenerative disorders.

  10. Prime-Boost Vaccination Using Chemokine-Fused gp120 DNA and HIV Envelope Peptides Activates Both Immediate and Long-Term Memory Cellular Responses in Rhesus Macaques

    Hong Qin

    2010-01-01

    Full Text Available HIV vaccine candidates with improved immunogenicity and induction of mucosal T-cell immunity are needed. A prime-boost strategy using a novel HIV glycoprotein 120 DNA vaccine was employed to immunize rhesus macaques. The DNA vaccine encoded a chimeric gp120 protein in fusion with monocyte chemoattractant protein-3, which was hypothesized to improve the ability of antigen-presenting cells to capture viral antigen through chemokine receptor-mediated endocytosis. DNA vaccination induced virus-reactive T cells in peripheral blood, detectable by T cell proliferation, INFγ ELISPOT and sustained IL-6 production, without humoral responses. With a peptide-cocktail vaccine containing a set of conserved polypeptides of HIV-1 envelope protein, given by nasogastric administration, primed T-cell immunity was significantly boosted. Surprisingly, long-term and peptide-specific mucosal memory T-cell immunity was detected in both vaccinated macaques after one year. Therefore, data from this investigation offer proof-of-principle for potential effectiveness of the prime-boost strategy with a chemokine-fused gp120 DNA and warrant further testing in the nonhuman primate models for developing as a potential HIV vaccine candidate in humans.

  11. Influence of the Melissa officinalis Leaf Extract on Long-Term Memory in Scopolamine Animal Model with Assessment of Mechanism of Action

    Marcin Ozarowski

    2016-01-01

    Full Text Available Melissa officinalis (MO, English: lemon balm, Lamiaceae, one of the oldest and still most popular aromatic medicinal plants, is used in phytomedicine for the prevention and treatment of nervous disturbances. The aim of our study was to assess the effect of subchronic (28-fold administration of a 50% ethanol extract of MO leaves (200 mg/kg, p.o. compared with rosmarinic acid (RA, 10 mg/kg, p.o. and huperzine A (HU, 0.5 mg/kg, p.o. on behavioral and cognitive responses in scopolamine-induced rats. The results were linked with acetylcholinesterase (AChE, butyrylcholinesterase (BuChE, and beta-secretase (BACE-1 mRNA levels and AChE and BuChE activities in the hippocampus and frontal cortex of rats. In our study, MO and HU, but not RA, showed an improvement in long-term memory. The results were in line with mRNA levels, since MO produced a decrease of AChE mRNA level by 52% in the cortex and caused a strong significant inhibition of BACE1 mRNA transcription (64% in the frontal cortex; 50% in the hippocampus. However, the extract produced only an insignificant inhibition of AChE activity in the frontal cortex. The mechanisms of MO action are probably more complicated, since its role as a modulator of beta-secretase activity should be taken into consideration.

  12. Effects of Long-Term Environmental Enrichment on Anxiety, Memory, Hippocampal Plasticity and Overall Brain Gene Expression in C57BL6 Mice

    Hüttenrauch, Melanie; Salinas, Gabriela; Wirths, Oliver

    2016-01-01

    There is ample evidence that physical activity exerts positive effects on a variety of brain functions by facilitating neuroprotective processes and influencing neuroplasticity. Accordingly, numerous studies have shown that continuous exercise can successfully diminish or prevent the pathology of neurodegenerative diseases such as Alzheimer’s disease in transgenic mouse models. However, the long-term effect of physical activity on brain health of aging wild-type (WT) mice has not yet been studied in detail. Here, we show that prolonged physical and cognitive stimulation, mediated by an enriched environment (EE) paradigm for a duration of 11 months, leads to reduced anxiety and improved spatial reference memory in C57BL6 WT mice. While the number of CA1 pyramidal neurons remained unchanged between standard housed (SH) and EE mice, the number of dentate gyrus (DG) neurons, as well as the CA1 and DG volume were significantly increased in EE mice. A whole-brain deep sequencing transcriptome analysis, carried out to better understand the molecular mechanisms underlying the observed effects, revealed an up-regulation of a variety of genes upon EE, mainly associated with synaptic plasticity and transcription regulation. The present findings corroborate the impact of continuous physical activity as a potential prospective route in the prevention of age-related cognitive decline and neurodegenerative disorders. PMID:27536216

  13. Temporary inactivation reveals that the CA1 region of the mouse dorsal hippocampus plays an equivalent role in the retrieval of long-term object memory and spatial memory.

    Stackman, Robert W; Cohen, Sarah J; Lora, Joan C; Rios, Lisa M

    2016-09-01

    Recognition of a previously experienced item or object depends upon the successful retrieval of memory for the object. The neural mechanisms that support object recognition memory in the mammalian brain are not well understood. The rodent hippocampus plays a well-established role in spatial memory, and we previously demonstrated that temporary inactivation of the mouse hippocampus impairs object memory, as assessed with a novel object preference (NOP) test. The present studies were designed to test some remaining issues regarding the contribution of the CA1 sub-region of the mouse dorsal hippocampus to long-term object memory. Specifically, we examined whether the retrieval of spatial memory (as assessed by the Morris water maze; MWM) and object recognition memory are differentially sensitive to inactivation of the CA1 region. The current study used pre-test local microinfusion of muscimol directly into the CA1 region of dorsal hippocampus to temporarily interrupt its function during the respective retrieval phases of both behavioral tasks, in order to compare the contribution of the CA1 to object memory and spatial memory. Histological analyses revealed that local intra-CA1 injection of muscimol diffused within, and not beyond, the CA1 region of dorsal hippocampus. The degree of memory retrieval impairment induced by muscimol was comparable in the two tasks, supporting the view that object memory and spatial memory depend similarly on the CA1 region of rodent hippocampus. Further, we confirmed that the muscimol-induced impairment of CA1 function is temporary. First, mice that exhibited impaired object memory retrieval immediately after intra-CA1 muscimol, subsequently exhibited unimpaired retrieval of object memory when tested 24h later. Secondly, a cohort of mice that exhibited impaired object memory retrieval after intra-CA1 muscimol later acquired spatial memory in the MWM comparable to that of control mice. Together, these results offer further support for the

  14. Long-term collections

    Collectes à long terme

    2007-01-01

    The Committee of the Long Term Collections (CLT) asks for your attention for the following message from a young Peruvian scientist, following the earthquake which devastated part of her country a month ago.

  15. Long-term X-Ray Spectral Variability in AGN from the Palomar sample observed by Swift

    Connolly, S D; Skipper, C J; Emmanoulopoulos, D

    2016-01-01

    We present X-ray spectral variability of 24 local active galactic nuclei (AGN) from the Palomar sample of nearby galaxies, as observed mainly by Swift. From hardness ratio measurements, we find that 18 AGN with low accretion rates show hardening with increasing count rate, converse to the softer-when-brighter behaviour normally observed in AGN with higher accretion rates. Two AGN show softening with increasing count rate, two show more complex behaviour, and two do not show any simple relationship. Sufficient data were available for the spectra of 13 AGN to be summed in flux-bins. In 9 of these sources, correlated luminosity-dependent changes in the photon index ($\\Gamma$) of a power-law component are found to be the main cause of hardness variability. For 6 objects, with a low accretion rate as a fraction of the Eddington rate (\\.m$\\mathrm{_{Edd}}$), $\\Gamma$ is anticorrelated with \\.m$\\mathrm{_{Edd}}$, i.e. `harder-when-brighter' behaviour is observed. The 3 higher-\\.m$\\mathrm{_{Edd}}$-rate objects show a p...

  16. Long-term X-ray spectral variability in AGN from the Palomar sample observed by Swift

    Connolly, S. D.; McHardy, I. M.; Skipper, C. J.; Emmanoulopoulos, D.

    2016-07-01

    We present X-ray spectral variability of 24 local active galactic nuclei (AGN) from the Palomar sample of nearby galaxies, as observed mainly by Swift. From hardness ratio measurements, we find that 18 AGN with low accretion rates show hardening with increasing count rate, converse to the softer-when-brighter behaviour normally observed in AGN with higher accretion rates. Two AGN show softening with increasing count rate, two show more complex behaviour, and two do not show any simple relationship. Sufficient data were available for the spectra of 13 AGN to be summed in flux-bins. In nine of these sources, correlated luminosity-dependent changes in the photon index (Γ) of a power-law component are found to be the main cause of hardness variability. For six objects, with a low accretion rate as a fraction of the Eddington rate (dot{m}_{Edd}), Γ is anticorrelated with dot{m}_{Edd}, i.e. `harder-when-brighter' behaviour is observed. The three higher dot{m}_{Edd}-rate objects show a positive correlation between Γ and dot{m}_{Edd}. This transition from harder-when-brighter at low dot{m}_{Edd}to softer-when-brighter at high dot{m}_{Edd} can be explained by a change in the dominant source of seed-photons for X-ray emission from cyclo-synchrotron emission from the Comptonizing corona itself to thermal seed-photons from the accretion disc. This transition is also seen in the `hard state' of black hole X-ray binaries (BHXRBs). The results support the idea that low-ionization nuclear emission-line regions are analogues of BHXRBs in the hard state and that Seyferts are analogues of BHXRBs in either the high-accretion rate end of the hard state or in the hard-intermediate state.

  17. Long-term storage of clinical samples in CyMol® medium for PNA- FISH® and culturing from the eSwab™ system

    Larsen, Lone Heimann; Xu, Yijuan; Pedersen, Malene Schibler;

    performed within 24 h after sampling. The corresponding specimens for culture-independent methods were stored at -80°C until analyzed in batchs. Specimens for fluorescence in situ hybridization (FISH) analysis were stored for app. one year at -80°C in CyMol® (Copan, Italy), an alcohol based media, before...... spp. by culture and 16S rRNA gene amplicon sequencing. Conclusion: It is possible to preserve samples for FISH and PNA-FISH® for long-term storage by using CyMol® with an effective detection limit in the order of >10^3 bacteria/mL. Both the morphology and intensity of staining with nucleic acid...

  18. Immunization of mice with the nef gene from Human Immunodeficiency Virus type 1: Study of immunological memory and long-term toxicology

    Engström Gunnel

    2007-07-01

    Full Text Available Abstract Background The human immunodeficiency virus type 1 (HIV-1 regulatory protein, Nef, is an attractive vaccine target because it is involved in viral pathogenesis, is expressed early in the viral life cycle and harbors many T and B cell epitopes. Several clinical trials include gene-based vaccines encoding this protein. However, Nef has been shown to transform certain cell types in vitro. Based on these findings we performed a long-term toxicity and immunogenicity study of Nef, encoded either by Modified Vaccinia virus Ankara or by plasmid DNA. BALB/c mice were primed twice with either DNA or MVA encoding Nef and received a homologous or heterologous boost ten months later. In the meantime, the Nef-specific immune responses were monitored and at the time of sacrifice an extensive toxicological evaluation was performed, where presence of tumors and other pathological changes were assessed. Results The toxicological evaluation showed that immunization with MVAnef is safe and does not cause cellular transformation or other toxicity in somatic organs. Both DNAnef and MVAnef immunized animals developed potent Nef-specific cellular responses that declined to undetectable levels over time, and could readily be boosted after almost one year. This is of particular interest since it shows that plasmid DNA vaccine can also be used as a potent late booster of primed immune responses. We observed qualitative differences between the T cell responses induced by the two different vectors: DNA-encoded nef induced long-lasting CD8+ T cell memory responses, whereas MVA-encoded nef induced CD4+ T cell memory responses. In terms of the humoral immune responses, we show that two injections of MVAnef induce significant anti-Nef titers, while repeated injections of DNAnef do not. A single boost with MVAnef could enhance the antibody response following DNAnef prime to the same level as that observed in animals immunized repeatedly with MVAnef. We also demonstrate

  19. Working memory training shows immediate and long-term effects on cognitive performance in children [v3; ref status: indexed, http://f1000r.es/4y9

    Fiona Pugin

    2015-01-01

    Full Text Available Working memory is important for mental reasoning and learning processes. Several studies in adults and school-age children have shown performance improvement in cognitive tests after working memory training. Our aim was to examine not only immediate but also long-term effects of intensive working memory training on cognitive performance tests in children. Fourteen healthy male subjects between 10 and 16 years trained a visuospatial n-back task over 3 weeks (30 min daily, while 15 individuals of the same age range served as a passive control group. Significant differences in immediate (after 3 weeks of training and long-term effects (after 2-6 months in an auditory n-back task were observed compared to controls (2.5 fold immediate and 4.7 fold long-term increase in the training group compared to the controls. The improvement was more pronounced in subjects who improved their performance during the training. Other cognitive functions (matrices test and Stroop task did not change when comparing the training group to the control group. We conclude that visuospatial working memory training in children boosts performance in similar memory tasks such as the auditory n-back task. The sustained performance improvement several months after the training supports the effectiveness of the training.

  20. Working memory training shows immediate and long-term effects on cognitive performance in children [v2; ref status: indexed, http://f1000r.es/4rj

    Fiona Pugin

    2014-11-01

    Full Text Available Working memory is important for mental reasoning and learning processes. Several studies in adults and school-age children have shown performance improvement in cognitive tests after working memory training. Our aim was to examine not only immediate but also long-term effects of intensive working memory training on cognitive performance tests in children. Fourteen healthy male subjects between 10 and 16 years trained a visuospatial n-back task over 3 weeks (30 min daily, while 15 individuals of the same age range served as a passive control group. Significant differences in immediate (after 3 weeks of training and long-term effects (after 2-6 months in an auditory n-back task were observed compared to controls (2.5 fold immediate and 4.7 fold long-term increase in the training group compared to the controls. The improvement was more pronounced in subjects who improved their performance during the training. Other cognitive functions (matrices test and Stroop task did not change when comparing the training group to the control group. We conclude that visuospatial working memory training in children boosts performance in similar memory tasks such as the auditory n-back task. The sustained performance improvement several months after the training supports the effectiveness of the training.

  1. Long-Term Collections

    Comité des collectes à long terme

    2011-01-01

    It is the time of the year when our fireman colleagues go around the laboratory for their traditional calendars sale. A part of the money of the sales will be donated in favour of the long-term collections. We hope that you will welcome them warmly.

  2. Social investigation and long-term recognition memory performance in 129S1/SvImJ and C57BL/6JOlaHsd mice and their hybrids.

    Jana Hädicke

    Full Text Available When tested for their behavioural performance, the mixed genetic background of transgenic mice is a critical, but often ignored, issue. Such issues can arise because of the significant differences in defined behavioural parameters between embryonic stem cell donor and recipient strains. In this context, the commonly used stem cell donor strain '129' shows 'deficits' in different paradigms for learning and long-term memory. We investigated the long-term social recognition memory performance and the investigative behaviour in commercially available 129S1/SvImJ and C57BL/6JOlaHsd mice and two F1-hybrids (129S1/SvImJ×C57BL/6JOlaHsd by using the social discrimination procedure and its modification, the volatile fraction cage (VFC. Our data revealed an unimpaired olfactory long-term recognition memory not only in female and male 129S1/SvImJ and C57BL/6JOlaHsd mice but also in the two hybrid lines (129S1/SvImJxC57BL/6JOlaHsd when the full 'olfactory signature' of the 'to-be-recognized' conspecific was presented. Under these conditions we also failed to detect differences in the long-term recognition memory between male and female mice of the tested strains and revealed that the oestrus cycle did not affect the performance in this memory task. The performance in the VFC, based only on the volatile components of the 'olfactory signature' of the 'to-be-recognized' conspecific, was similar to that observed under direct exposure except that females of one F1 hybrid group failed to show an intact long-term memory. Thus, the social discrimination procedure allowing direct access between the experimental subject and the stimulus animal(s is highly suitable to investigate the impact of genetic manipulations on long-term memory in male and female mice of the strain 129S1/SvImJ, C57BL/6JOlaHsd and 129S1/SvImJxC57BL/6JOlaHsd hybrids.

  3. Evaluation of the Quality of Life in Adult Cancer Survivors (QLACS scale for long-term cancer survivors in a sample of breast cancer survivors

    Foley Kristie

    2006-12-01

    Full Text Available Abstract Background This paper evaluates psychometric properties of a recently developed measure focusing on the health-related quality of life (HRQL of long-term cancer survivors, the Quality of Life in Adult Survivors scale (QLACS, in a sample of breast cancer survivors. This represents an important area of study, given the large number of breast cancer patients surviving many years post diagnosis. Methods Analyses are based on an 8-year follow-up of a sample of breast cancer survivors who participated in an earlier study conducted in 1995. Participants were re-contacted in 2003 and those who were reachable and agreed to participate (n = 94 were surveyed using a variety of measures including the QLACS. Additional follow-up surveys were conducted 2 weeks and one year later. Psychometric tests of the QLACS included test-retest reliability, concurrent and retrospective validity, and responsiveness. Results The QLACS domain and summary scores showed good test-retest reliability (all test-retest correlations were above .7 and high internal consistency. The Generic Summary Score showed convergent validity with other measures designed to assess generic HRQL. The Cancer-Specific Summary score exhibited divergent validity with generic HRQL measures, but not a cancer-related specific measure. The QLACS Cancer-Specific Summary Score demonstrated satisfactory predictive validity for factors that were previously shown to be correlated with HRQL. The QLACS generally demonstrated a high level of responsiveness to life changes. Conclusion The QLACS may serve as a useful measure for assessing HRQL among long-term breast cancer survivors that are not otherwise captured by generic measures or those specifically designed for newly diagnosed patients.

  4. Effects of standardized Ginkgo biloba extract on the acquisition, retrieval and extinction of conditioned suppression: Evidence that short-term memory and long-term memory are differentially modulated.

    Zamberlam, C R; Vendrasco, N C; Oliveira, D R; Gaiardo, R B; Cerutti, S M

    2016-10-15

    Studies in our laboratory have characterized the putative neuromodulatory effects of a standardized extract of the green leaves of Ginkgo biloba (EGb), which comprises a formulation of 24% ginkgo-flavoglycosides and 6% ginkgo-terpenoid lactones, on conditioned suppression. This model comprises a suitable animal model for investigating the behavioral changes and pharmacological mechanisms that underlie fear memory and anxiety. The characterization of the effects on distinct stages of fear memory or fear extinction will help illustrate both the beneficial and harmful effects. Three hundred adult male Wistar rats were randomly assigned to 30 groups according to the treatment as follows: i-ii) control groups (CS-US and CSno-US); iii) vehicle group (12% Tween®80); and iv-vi) EGb groups (250, 500 and 1000mgkg(-1)); or experimental procedures designed to assess the effects of EGb treatment prior to the acquisition (n=20 per group) and retrieval of conditioned fear (n=10 per group) or prior to the extinction training (n=10 per group) and extinction retention test (n=10 per group). Furthermore, to better understand the effects of acute EGb treatment on fear memory, we conducted two additional analyses: the acquisition of within- and between-session extinction of fear memory (short- and long-term memory, respectively). No difference was identified between the control and treatment groups during the retention test (P>0.05), with the exception of the CSno-US group in relation to all groups (Pmemory, which was verified by the suppression ration in the first trial of extinction training (SR=0.39) and the extinction retention test session (SR=0.53, Pmemory acquisition, which were evaluated during the retention test (SR=0.79). Moreover, EGb administered at 1000mgkg(-1) prior to conditioning did not enhance the long-term extinction memory, i.e., it did not prevent the return of extinguished fear memory in the extinction retention test, in which the spontaneous recovery of fear was

  5. A minimally invasive method of piscine tissue collection and an analysis of long-term field-storage conditions for samples

    Smalley John V

    2006-05-01

    Full Text Available Abstract Background The acquisition of high-quality DNA for use in phylogenetic and molecular population genetic studies is a primary concern for evolutionary and genetic researchers. Many non-destructive DNA sampling methods have been developed and are used with a variety of taxa in applications ranging from genetic stock assessment to molecular forensics. Results The authors have developed a field sampling method for obtaining high-quality DNA from sunfish (Lepomis and other freshwater fish that employs a variation on the buccal swab method and results in the collection of DNA suitable for PCR amplification and polymorphism analysis. Additionally, since the circumstances of storage are always a concern for field biologists, the authors have tested the potential storage conditions of swabbed samples and whether those conditions affect DNA extraction and PCR amplification. It was found that samples stored at room temperature in the dark for over 200 days could still yield DNA suitable for PCR amplification and polymorphism detection. Conclusion These findings suggest that valuable molecular genetic data may be obtained from tissues that have not been treated or stored under optimal field conditions. Furthermore, it is clear that the lack of adequately low temperatures during transport and long term storage should not be a barrier to anyone wishing to engage in field-based molecular genetic research.

  6. Influence of Pre-Training Predator Stress on the Expression of c-fos mRNA in the Hippocampus, Amygdala and Striatum Following Long-Term Spatial Memory Retrieval

    Michael B VanElzakker

    2011-06-01

    Full Text Available We have studied the influence of pre-training psychological stress on the expression of c-fos mRNA following long-term spatial memory retrieval. Rats were trained to learn the location of a hidden escape platform in the radial-arm water maze, and then their memory for the platform location was assessed 24 hr later. Rat brains were extracted 30 min after the 24 hr memory test trial for analysis of c-fos mRNA. Four groups were tested: 1 Rats given standard training (Standard; 2 Rats given cat exposure (Predator Stress 30 min prior to training (Pre-Training Stress; 3 Rats given water exposure only (Water Yoked; and 4 Rats given no water exposure (Home Cage. The Standard trained group exhibited excellent 24 hr memory which was accompanied by increased c-fos mRNA in the dorsal hippocampus and basolateral amygdala (BLA. The Water Yoked group exhibited no increase in c-fos mRNA in any brain region. Rats in the Pre-Training Stress group were classified into two subgroups: good and bad memory performers. Neither of the two Pre-Training Stress subgroups exhibited a significant change in c-fos mRNA expression in the dorsal hippocampus or BLA. Instead, stressed rats with good memory exhibited significantly greater c-fos mRNA expression in the dorsolateral striatum (DLS compared to stressed rats with bad memory. This finding suggests that stressed rats with good memory used their DLS to generate a non-spatial (cue-based strategy to learn and subsequently retrieve the memory of the platform location. Collectively, these findings provide evidence at a molecular level for the involvement of the hippocampus and BLA in the retrieval of spatial memory and contribute novel observations on the influence of pre-training stress in activating the DLS in response to long-term memory retrieval.

  7. Mini-CORK observatories using the MeBo seafloor drill rig - a new development for long-term data acquisition and sampling in shallow boreholes

    Kopf, A.; Freudenthal, T.; Ratmeyer, V.; Bergenthal, M.; Renken, J.; Zabel, M.; Wefer, G.

    2011-12-01

    State of the art technology for long-term monitoring of fluid migration within the sea floor is the sealing of a borehole with a Circulation Obviation Retrofit Kit (CORK) after sensor installation and/or fluid sampling devices within the drill string. However, the combined used of a drilling vessels and a remotely operated drilling (ROV) required for a CORK installation in the deep sea is a costly exercise that limits the number of monitoring stations installed. Robotic sea floor drill rigs are a cost effective alternative for shallow drillings down to 50-100 m below sea floor. Here we present a Mini-CORK system that is developed for installation with the sea floor drill rig MeBo. This rig was developed at MARUM Research Centre, University of Bremen in 2005 and can sample the sea floor in water depths up to 2000 m. The MeBo is deployed on the seabed and remotely controlled from the vessel. All required drill tools for wire-line core drilling down to 70 m below sea floor are stored on two rotating magazines and can be loaded below the top drive drill head for assembling the drill string. For one of the upcoming cruises with RV Sonne offshore Japan (Nankai Trough accretionary prism), MeBo will be used for the first time to place observatories. Two different designs have been developed. The first, relatively simple long-term device resembles a MeBo drill rod in its geometry, and contains a pressure and temperature transducer in the borehole plus an identical pair of transducers for seafloor reference. The device also contains a data logger, battery unit, and an acoustic modem so that data can be downloaded at any time from a ship of opportunity. The key element at the base of the observatory rod is a seal at the conical thread to separate the borehole hydraulically from the overlying water body. It is realized by an adapter, which also contains a hotstab hydraulic connection and an electrical connection. The second observatory device is a seafloor unit, which replaces

  8. Role of the Phosphoinositide 3-Kinase-Akt-Mammalian Target of the Rapamycin Signaling Pathway in Long-Term Potentiation and Trace Fear Conditioning Memory in Rat Medial Prefrontal Cortex

    Sui, Li; Wang, Jing; Li, Bao-Ming

    2008-01-01

    Phosphatidylinositol 3-kinase (PI3K) and its downstream targets, including Akt (also known as protein kinase B, PKB), mammalian target of rapamycin (mTOR), the 70-kDa ribosomal S6 kinase (p70S6k), and the eukaryotic initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1), may play important roles in long-term synaptic plasticity and memory in many…

  9. Long-term reliable physically unclonable function based on oxide tunnel barrier breakdown on two-transistors two-magnetic-tunnel-junctions cell-based embedded spin transfer torque magnetoresistive random access memory

    Takaya, Satoshi; Tanamoto, Tetsufumi; Noguchi, Hiroki; Ikegami, Kazutaka; Abe, Keiko; Fujita, Shinobu

    2017-04-01

    Among the diverse applications of spintronics, security for internet-of-things (IoT) devices is one of the most important. A physically unclonable function (PUF) with a spin device (spin transfer torque magnetoresistive random access memory, STT-MRAM) is presented. Oxide tunnel barrier breakdown is used to realize long-term stability for PUFs. A secure PUF has been confirmed by evaluating the Hamming distance of a 32-bit STT-MRAM-PUF fabricated using 65 nm CMOS technology.

  10. Evaluation of a low-cost procedure for sampling, long-term storage, and extraction of RNA from blood for qPCR analyses

    Mærkedahl, Rasmus Baadsgaard; Frøkiær, Hanne; Lauritzen, Lotte

    2015-01-01

    Abstract Background: In large clinical trials, where RNA cannot be extracted immediately after sampling, preserving RNA in whole blood is a crucial initial step in obtaining robust qPCR data. The current golden standard for RNA preservation is costly and designed for time-consuming column-based RNA......-extraction. We investigated the use of lysis buffer for long-term storage of blood samples for qPCR analysis. Methods: Blood was collected from 13 healthy adults and diluted in MagMAX lysis/binding solution or PAXgene Blood RNA tubes and stored at -20 °C for 0, 1, or 4 months before RNA extraction...... by the matching method. RNA integrity, yield and purity were evaluated and the methods were compared by subsequent analyses of the gene expression levels of 18S, ACTB, IL1B, IL1RN, IL1R2, and PGK1 using qPCR. Results: The MagMAX system extracted 2.3-2.8 times more RNA per mL blood, with better performance...

  11. Long-term Course of Alzheimer Disease in Patients Treated According to the Dutch Dementia Guideline at a Memory Clinic A "Real-Life" Study

    Droogsma, Erika; van Asselt, Dieneke; van Steijn, Jolanda; Diekhuis, Marjolein; Veeger, Nic; De Deyn, Peter P.

    2016-01-01

    Introduction:There is little knowledge of the long-term course of Alzheimer disease (AD) in light of current pharmacological and nonpharmacological interventions provided in a real-life setting.Methods:The Frisian Alzheimer's Disease Cohort study is a real-life study of the course of AD in patients

  12. Long-Term Collections

    Staff Association

    2016-01-01

    45 years helping in developing countries! CERN personnel have been helping the least fortunate people on the planet since 1971. How? With the Long-Term Collections! Dear Colleagues, The Staff Association’s Long-Term Collections (LTC) Committee is delighted to share this important milestone in the life of our Laboratory with you. Indeed, whilst the name of CERN is known worldwide for scientific discoveries, it also shines in the many humanitarian projects which have been supported by the LTC since 1971. Several schools and clinics, far and wide, carry its logo... Over the past 45 years, 74 projects have been supported (9 of which are still ongoing). This all came from a group of colleagues who wanted to share a little of what life offered them here at CERN, in this haven of mutual understanding, peace and security, with those who were less fortunate elsewhere. Thus, the LTC were born... Since then, we have worked as a team to maintain the dream of these visionaries, with the help of regular donat...

  13. Long-Term Collection

    Staff Association

    2016-01-01

    Dear Colleagues, As previously announced in Echo (No. 254), your delegates took action to draw attention to the projects of the Long-Term Collections (LTC), the humanitarian body of the CERN Staff Association. On Tuesday, 11 October, at noon, small Z-Cards were widely distributed at the entrances of CERN restaurants and we thank you all for your interest. We hope to have achieved an important part of our goal, which was to inform you, convince you and find new supporters among you. We will find out in the next few days! An exhibition of the LTC was also set up in the Main Building for the entire week. The Staff Association wants to celebrate the occasion of the Long-Term Collection’s 45th anniversary at CERN because, ever since 1971, CERN personnel have showed great support in helping the least fortunate people on the planet in a variety of ways according to their needs. On a regular basis, joint fundraising appeals are made with the Directorate to help the victims of natural disasters around th...

  14. Collectes à long terme

    Collectes à long terme

    2014-01-01

    En cette fin d’année 2014 qui approche à grands pas, le Comité des Collectes à Long Terme remercie chaleureusement ses fidèles donatrices et donateurs réguliers pour leurs contributions à nos actions en faveur des plus démunis de notre planète. C’est très important, pour notre Comité, de pouvoir compter sur l’appui assidu que vous nous apportez. Depuis plus de 40 ans maintenant, le modèle des CLT est basé principalement sur des actions à long terme (soit une aide pendant 4-5 ans par projet, mais plus parfois selon les circonstances), et sa planification demande une grande régularité de ses soutiens financiers. Grand MERCI à vous ! D’autres dons nous parviennent au cours de l’année, et ils sont aussi les bienvenus. En particulier, nous tenons à remercier...

  15. Implications of psychosocial stress on memory formation in a typical male versus female student sample.

    Cornelisse, Sandra; van Stegeren, Anda H; Joëls, Marian

    2011-05-01

    Stress is known to differentially modulate memory function. Memory can be impaired or strengthened by stress, depending on e.g. the memory type and phase under study, the emotional value of the learned information and the sex of the subjects. Here, we addressed the latter and investigated the impact of psychosocial stress on long-term memory for neutral and emotional pictures and working memory in typical samples of male versus female students. In total, 77 subjects (54 women of which 39 used oral contraceptives) were exposed to either the Trier Social Stress Test (TSST) or a control condition, and then engaged in a long-term memory task (emotionally arousing and neutral pictures; surprise recall after one week) and a working memory (n-back) task. During the experiment salivary cortisol and alpha-amylase levels as well as subjective affect state were assessed. As expected, stress hormone concentrations as well as subjective negative affect states increased significantly in response to the stress task. Men reacted more to the stressor in terms of cortisol responses than women, probably due to oral contraceptive use of the latter. Results show that, in male as well as in female students, memory for emotional arousing information was better than for neutral information, in both the stress and control condition. Stress enhanced recognition memory for emotional versus neutral pictures only in male subjects. Moreover, stress enhanced working memory, particularly in males, during the first block of a 2-back task. The lack of stress effects on memory in women might be explained by oral contraceptive use, leading to blunted HPA-axis responses and secondary to reduced stress effects on memory. The results emphasize that stress affects both long-term and working memory differentially in male versus female students.

  16. A model of the mechanism of cooperativity and associativity of long-term potentiation in the hippocampus: a fundamental mechanism of associative memory and learning.

    Kitajima, T; Hara, K

    1991-01-01

    Long-Term Potentiation (LTP) has three properties: (1) input specificity, (2) cooperativity and (3) associativity. In a previous paper, we proposed an integrated model of the mechanisms of the induction and maintenance of LTP with input specificity. In this paper, a model of the mechanism of cooperative and associative LTP is described. According to computer simulations of the model, its mechanism is based on the spread of synaptic potentials.

  17. A model of long-term memory storage in the cerebellar cortex: A possible role for plasticity at parallel fiber synapses onto stellate/basket interneurons

    Kenyon, Garrett T.

    1997-01-01

    By evoking changes in climbing fiber activity, movement errors are thought to modify synapses from parallel fibers onto Purkinje cells (pf*Pkj) so as to improve subsequent motor performance. Theoretical arguments suggest there is an intrinsic tradeoff, however, between motor adaptation and long-term storage. Assuming a baseline rate of motor errors is always present, then repeated performance of any learned movement will generate a series of climbing fiber-mediated corrections. By reshuffling...

  18. EUCROMIC (European Collaborative Research on Mosaicism in Chorionic Villus Sampling): New initiatives concerning uniparental disomy research and long-term clinical follow-up

    DeLozier-Blanchet, C.D.; Hahnemann, J.M.; Vejersley, L.O.

    1994-09-01

    Since 1986 the European collaborative study on mosaicism in chorionic villus sampling (CVS), based in Glostrup, Denmark. has been collecting cytogenetic and clinical data on pregnancies in which testing revealed mosaicism or fetal/extrafetal chromosomal discrepancies. From 1986-1992, data on 60,823 samples, including 751 mosaics and 241 nonmosaic discrepancies, was collected. This information has proven helpful in prenatal counseling, by indicating which chromosomes are most often involved in mosaicism, whether the latter is likely to be confirmed in the fetus and/or placenta, and the relationship of cytogenetic results obtained by different culture techniques to pregnancy outcome. Since December 1, 1993 the European collaborative study has been funded by the European Community and by the Swiss government as a concertation project, {open_quotes}EUCROMIC{close_quotes}, a step which has allowed enlargement of the database and broadening of the project goals. Forty-five genetics centers are currently involved in this effort to monitor not only CVS, but changing trends in prenatal diagnosis in Europe. Two ancillary projects, based in Geneva, were initiated in early 1993: long-term clinical follow-up of children born after CVS mosaicism, and a search for uniparental disomy (UPD) in these same children (as well as in abortuses). Clinical data is collected from the initial reporting centers via questionnaires; at the time of writing, clinical follow-up has been obtained for over 250 children liveborn after CVS mosaicism. UPD testing results are received from the individual centers; for those not having the possibility to do the parental origin analyses themselves, testing is offered in one of several EUCROMIC-UPD laboratories.

  19. A long-term study of AGN X-ray variability . Structure function analysis on a ROSAT-XMM quasar sample

    Middei, R.; Vagnetti, F.; Bianchi, S.; La Franca, F.; Paolillo, M.; Ursini, F.

    2017-03-01

    Context. Variability in the X-rays is a key ingredient in understanding and unveiling active galactic nuclei (AGN) properties. In this band, flux variations occur on short timescales (hours) as well as on larger timescales. While short timescale variability is often investigated in single source studies, only a few works are able to explore flux variation on very long timescales. Aims: This work aims to provide a statistical analysis of the AGN long term X-ray variability. We study variability on the largest time interval ever investigated for the 0.2-2 keV band, up to approximately 20 yr rest-frame for a sample of 220 sources. Moreover, we study variability for 2700 quasars up to approximatley eight years rest-frame in the same (soft) band. Methods: We built our source sample using the 3XMM serendipitous source catalogue data release 5, and data from ROSAT All Sky Survey Bright and Faint source catalogues. To ensure that we selected AGN only, we used the Sloan Digital Sky Survey quasar catalogues data releases 7 and 12. Combining ROSAT and XMM-Newton observations, we investigated variability using the structure function analysis which describes the amount of variability as a function of the lag between the observations. Results: Our work shows an increase of the structure function up to 20 yr. We find no evidence of a plateau in the structure function on these long timescales. Conclusions: The increase of the structure function at long time lags suggests that variability in the soft X-rays can be influenced by flux variations originated in the accretion disk or that they take place in a region large enough to justify variation on such long timescales.

  20. Influence of long-term mineral fertilization on metal contents and properties of soil samples taken from different locations in Hesse, Germany

    Czarnecki, S.; Düring, R.-A.

    2015-01-01

    Essential and non-essential metals occur in soils as a result of weathering, industrial processes, fertilization, and atmospheric deposition. Badly adapted cultivation of agricultural soils (declining pH value, application of unsuitable fertilizers) can enhance the mobility of metals and thereby increase their concentrations in agricultural products. As the enrichment of metals in soils occurs over long time periods, monitoring of the long-term impact of fertilization is necessary to assess metal accumulation in agricultural soils. The main objective of this study was to test the effects of different mineral fertilizer variations on soil properties (pH, Corg, and cation exchange capacity (CEC)) and pseudo-total and mobile metal contents of soils after 14 years of fertilizer application and to determine residual effects of the fertilization 8 years after cessation of fertilizer treatment. Soil samples were taken from a field experiment which was carried out at four different locations (210, 260, 360, and 620 m above sea level) in Hesse, Germany. During the study, a significant decrease in soil pH and an evident increase in soil carbon content and cation exchange capacity with fertilization were determined. The CEC of the soils was closely related to their organic C contents. Moreover, pseudo- and mobile metal (Cd, Cu, Mn, Pb, Zn) contents in the soils increased due to application of 14 years of mineral fertilizer treatments (N, P, NP, and NPK) when compared to control plots. Eight years after termination of the fertilization in the soil samples taken from soil profiles of the fertilized plots (NPK) for monitoring the residual effects of the fertilizer application, a decrease of 82.6, 54.2, 48.5, 74.4, and 56.9% in pseudo-total Cd, Cu, Mn, Pb, and Zn contents, respectively, was determined.

  1. LONG TERM COLLECTIONS

    STAFF ASSOCIATION

    2010-01-01

    ACKNOWLEDGMENTS The Long-Term Collections (CLT) committee would like to warmly thank its faithful donors who, year after year, support our actions all over the world. Without you, all this would not be possible. We would like to thank, in particular, the CERN Firemen’s Association who donated 5000 CHF in the spring thanks to the sale of their traditional calendar, and the generosity of the CERN community. A huge thank you to the firemen for their devotion to our cause. And thank you to all those who have opened their door, their heart, and their purses! Similarly, we warmly thank the CERN Yoga Club once again for its wonderful donation of 2000 CHF we recently received. We would also like to tell you that all our projects are running well. Just to remind you, we are currently supporting the activities of the «Réflexe-Partage» Association in Mali; the training centre of «Education et Développement» in Abomey, Benin; and the orphanage and ...

  2. Application of long-term cultured interferon-gamma enzyme-linked immunospot assay for assessing effector and memory T cell responses in cattle

    Effector and memory T cells are generated through developmental programing of naïve cells following antigen recognition. If the infection is controlled, up to 95% of the T cells generated during the expansion phase are eliminated (i.e., contraction phase) and memory T cells remain, sometimes for a l...

  3. Long-term immunogenicity and immune memory after two doses of the adult formulation of a combined hepatitis A and B vaccine in children 1 to 11 years of age.

    van Damme, Pierre; Kafeja, Froukje; Van Der Wielen, Marie; Leyssen, Maarten; Jacquet, Jeanne-Marie

    2011-08-01

    Long-term persistence of antibodies against hepatitis A and B (anti-HAV and anti-HBs) were evaluated in 1- to 11-year-old children following 2 doses (0, 6 months) of hepatitis A and B vaccine. Ten years postvaccination, all subjects were anti-HAV seropositive (≥15 mIU/mL), 81.7% had anti-HBs antibody concentrations ≥10 mIU/mL. All subjects with anti-HBs concentrations vaccine challenge dose indicating the presence of immunologic memory against hepatitis B.

  4. Long-term follow-up on affinity maturation and memory B-cell generation in patients with common variable immunodeficiency

    Ballegaard, Vibe Cecilie Diederich; Permin, H; Katzenstein, T L

    2013-01-01

    Common variable immunodeficiency (CVID) comprises a heterogeneous group of primary immunodeficiency disorders. Immunophenotyping of memory B cells at the time of diagnosis is increasingly used for the classification of patients into subgroups with different clinical prognoses. The EUROclass...

  5. LONG TERM COLLECTIONS

    2004-01-01

    The Committee would like to thank all those, from near and far, who kindly gave donations to the collection organized at the time of the sudden death of our friend and colleague Stephen O'NEALE The sum of 3,615 francs will be sent to the INEPE Association for the education of children in Quito, Ecuador. We are deeply grateful for this gesture from Steve's family and hope that they find comfort in knowing that Steve's memory will live on through the children whose daily lives will be improved by this gift.

  6. The timing of learning before night-time sleep differentially affects declarative and procedural long-term memory consolidation in adolescents.

    Johannes Holz

    Full Text Available Sleep after learning has been shown to foster the consolidation of new memories. However, fundamental questions on the best timing of learning before night-time sleep persist. We tested the hypothesis that learning directly prior to night-time sleep compared to 7.5 hrs prior to night-time sleep provides better conditions for the consolidation of declarative and procedural memories. Fifty healthy female adolescents (aged 16-17 years were trained on a declarative word-pair and a procedural finger-tapping task at 3 pm (afternoon group, n = 25 or at 9 pm (evening group, n = 25, followed by a sleep laboratory night. Retrieval was assessed 24 hours and 7 days after initial training. Subjects trained in the afternoon showed a significantly elevated retention rate of word-pairs compared to subjects trained in the evening after 24 hours, but not after 7 days. In contrast, off-line gains in finger-tapping performance were significantly higher in subjects trained in the evening compared to those trained in the afternoon after both retention intervals. The observed enhanced consolidation of procedural memories after training in the evening fits to current models of sleep-related memory consolidation. In contrast, the higher retention of declarative memories after encoding in the afternoon is surprising, appeared to be less robust and needs further investigation.

  7. The timing of learning before night-time sleep differentially affects declarative and procedural long-term memory consolidation in adolescents.

    Holz, Johannes; Piosczyk, Hannah; Landmann, Nina; Feige, Bernd; Spiegelhalder, Kai; Riemann, Dieter; Nissen, Christoph; Voderholzer, Ulrich

    2012-01-01

    Sleep after learning has been shown to foster the consolidation of new memories. However, fundamental questions on the best timing of learning before night-time sleep persist. We tested the hypothesis that learning directly prior to night-time sleep compared to 7.5 hrs prior to night-time sleep provides better conditions for the consolidation of declarative and procedural memories. Fifty healthy female adolescents (aged 16-17 years) were trained on a declarative word-pair and a procedural finger-tapping task at 3 pm (afternoon group, n = 25) or at 9 pm (evening group, n = 25), followed by a sleep laboratory night. Retrieval was assessed 24 hours and 7 days after initial training. Subjects trained in the afternoon showed a significantly elevated retention rate of word-pairs compared to subjects trained in the evening after 24 hours, but not after 7 days. In contrast, off-line gains in finger-tapping performance were significantly higher in subjects trained in the evening compared to those trained in the afternoon after both retention intervals. The observed enhanced consolidation of procedural memories after training in the evening fits to current models of sleep-related memory consolidation. In contrast, the higher retention of declarative memories after encoding in the afternoon is surprising, appeared to be less robust and needs further investigation.

  8. Long-term cilostazol administration ameliorates memory decline in senescence-accelerated mouse prone 8 (SAMP8) through a dual effect on cAMP and blood-brain barrier.

    Yanai, Shuichi; Toyohara, Jun; Ishiwata, Kiichi; Ito, Hideki; Endo, Shogo

    2016-12-12

    Phosphodiesterases (PDEs), which hydrolyze and inactivate 3', 5'-cyclic adenosine monophosphate (cAMP) and 3', 5'-cyclic guanosine monophosphate (cGMP), play an important role in synaptic plasticity that underlies memory. Recently, several PDE inhibitors were assessed for their possible therapeutic efficacy in treating cognitive disorders. Here, we examined how cilostazol, a selective PDE3 inhibitor, affects brain functions in senescence-accelerated mouse prone 8 (SAMP8), an animal model of age-related cognitive impairment. Long-term administration of cilostazol restored the impaired context-dependent conditioned fear memory of SAMP8 to match that in normal aging control substrain SAMR1. Cilostazol also increased the number of cells containing phosphorylated cAMP-responsive element binding protein (CREB), a downstream component of the cAMP pathway. Finally, cilostazol improves blood-brain barrier (BBB) integrity, demonstrated by reduced extravasation of 2-deoxy-2-(18)F-fluoro-d-glucose and Evans Blue dye in the brains of SAMP8. This improvement in BBB integrity was associated with an increased amount of zona occludens protein 1 (ZO-1) and occludin proteins, components of tight junctions integral to the BBB. The results suggest that long-term administration of cilostazol exerts its beneficial effects on age-related cognitive impairment through a dual mechanism: by enhancing the cAMP system in the brain and by maintaining or improving BBB integrity.

  9. 转录因子Egr-1参与长期性恐惧记忆和焦虑%Transcription factor Egr-1 is required for long-term fear memory and anxiety

    Shanelle; W.Ko; 敖虎山; Amelia; Gallitano-Mendel; 邱长申; 魏峰; Jeffrey; Milbrandt; 卓敏

    2005-01-01

    The zinc finger transcription factor Egr-1 is critical for coupling extracellular signals to changes in cellular gene expression.In the hippocampus and amygdala, two major central regions for memory formation and storage, Egr-1 is up-regulated by long-term potentiation (LTP) and learning paradigms. Using Egr-1 knockout mice, we showed that Egr-1 was selectively required for late auditory fear memory while short term, trace and contextual memory were not affected. Additionally, synaptic potentiation induced by theta burst stimulation in the amygdala and auditory cortex was significantly reduced or blocked in Egr-1 knockout mice. Our study suggests that the transcription factor Egr-1 plays a selective role in late auditory fear memory.%锌指转录因子Egr-1在将细胞外信号和胞内基因表达的变化相耦联过程中发挥重要的作用.海马和杏仁体是记忆形成和储存的两个主要的脑区.在海马和杏仁体中,Egr-1可被长时程增强(long-term potentiation,LTP)和学习过程上调.在Egr-1敲除小鼠上观察到晚时相声音恐惧记忆受损,而短时的痕迹和场景记忆却不受影响;另外,在Egr-1敲除小鼠上,用thetaburst刺激杏仁体和听觉皮层所引起的突触增强被明显减弱或完全阻断.因此,我们的研究表明,转录因子Egr-1选择性地在晚时相听觉恐惧记忆中发挥作用.

  10. Duration of the Unconditioned Stimulus in Appetitive Conditioning of Honeybees Differentially Impacts Learning, Long-Term Memory Strength, and the Underlying Protein Synthesis

    Marter, Kathrin; Grauel, M. Katharina; Lewa, Carmen; Morgenstern, Laura; Buckemüller, Christina; Heufelder, Karin; Ganz, Marion; Eisenhardt, Dorothea

    2014-01-01

    This study examines the role of stimulus duration in learning and memory formation of honeybees ("Apis mellifera"). In classical appetitive conditioning honeybees learn the association between an initially neutral, conditioned stimulus (CS) and the occurrence of a meaningful stimulus, the unconditioned stimulus (US). Thereby the CS…

  11. Dopamine D1 Receptors Regulate Protein Synthesis-Dependent Long-Term Recognition Memory via Extracellular Signal-Regulated Kinase 1/2 in the Prefrontal Cortex

    Nagai, Taku; Takuma, Kazuhiro; Kamei, Hiroyuki; Ito, Yukio; Nakamichi, Noritaka; Ibi, Daisuke; Nakanishi, Yutaka; Murai, Masaaki; Mizoguchi, Hiroyuki; Nabeshima, Toshitaka; Yamada, Kiyofumi

    2007-01-01

    Several lines of evidence suggest that extracellular signal-regulated kinase1/2 (ERK1/2) and dopaminergic system is involved in learning and memory. However, it remains to be determined if the dopaminergic system and ERK1/2 pathway contribute to cognitive function in the prefrontal cortex (PFC). The amount of phosphorylated ERK1/2 was increased in…

  12. Traumatic memories, post-traumatic stress disorder and serum cortisol levels in long-term survivors of the acute respiratory distress syndrome

    Hauer, Daniela; Weis, Florian; Krauseneck, Till; Vogeser, Michael; Schelling, Gustav; Roozendaal, Benno

    2009-01-01

    Survivors of the acute respiratory distress syndrome (ARDS) often report traumatic memories from the intensive care unit (ICU) and display a high incidence of post-traumatic stress disorder (PTSD). As it is known that subjects with PTSD often show sustained reductions in circulating cortisol concent

  13. The Effect of Insulin and Insulin-Like Growth Factors on Hippocampus- and Amygdala-Dependent Long-Term Memory Formation

    Stern, Sarah A.; Chen, Dillon Y.; Alberini, Cristina M.

    2014-01-01

    Recent work has reported that the insulin-like growth factor 2 (IGF2) promotes memory enhancement. Furthermore, impaired insulin or IGF1 functions have been suggested to play a role in the pathogenesis of neurodegeneration and cognitive impairments, hence implicating the insulin/IGF system as an important target for cognitive enhancement and/or…

  14. The group I metabotropic glutamate receptor mGluR5 is required for fear memory formation and long-term potentiation in the lateral amygdala.

    Rodrigues, Sarina M; Bauer, Elizabeth P; Farb, Claudia R; Schafe, Glenn E; LeDoux, Joseph E

    2002-06-15

    The group I metabotropic glutamate receptor subtype mGluR5 has been shown to play a key role in the modulation of synaptic plasticity. The present experiments examined the function of mGluR5 in the circuitry underlying Pavlovian fear conditioning using neuroanatomical, electrophysiological, and behavioral techniques. First, we show using immunocytochemical and tract-tracing methods that mGluR5 is localized to dendritic shafts and spines in the lateral nucleus of the amygdala (LA) and is postsynaptic to auditory thalamic inputs. In electrophysiological experiments, we show that long-term potentiation at thalamic input synapses to the LA is impaired by bath application of a specific mGluR5 antagonist, 2-methyl-6-(phenyle-thynyl)-pyridine (MPEP), in vitro. Finally, we show that intra-amygdala administration of MPEP dose-dependently impairs the acquisition, but not expression or consolidation, of auditory and contextual fear conditioning. Collectively, the results of this study indicate that mGluR5 in the LA plays a crucial role in fear conditioning and in plasticity at synapses involved in fear conditioning.

  15. Rapid Eye Movement Sleep deprivation produces long-term detrimental effects in spatial memory and modifies the cellular composition of the subgranular zone

    Sofia eSoto-Rodriguez

    2016-05-01

    Full Text Available Sleep deprivation (SD affects spatial memory and proliferation in the dentate gyrus. It is unknown whether these deleterious effects persist in the long run. The aim of this study was to evaluate the proliferation, differentiation and maturation of neural progenitors as well as spatial memory 21 days after suffering sleep deprivation. Sixty-day old male Balb/C mice were exposed to 72-h REM-SD. Spatial memory, cell fate, apoptosis and expression levels of insulin-like growth factor 1 receptor (IGF-1R were evaluated in the hippocampus at 0, 14 and 21 days after SD or control conditions. After 21-d recovery period, memory performance was assessed with the Barnes maze, we found a significant memory impairment in SD mice vs. control (94.0 ± 10.2s vs. 25.2 ± 4.5s; p < 0.001. The number of BrdU+ cells was significantly decreased in the SD groups at day 14 (controls = 1.6 ± 0.1 vs. SD mice = 1.2 ± 0.1 cells/field; p=0.001 and at day 21 (controls = 0.2 ± 0.03 vs. SD mice = 0.1 ± 0.02 cells/field; p < 0.001. A statistically significant decrease was observed in neuronal differentiation (1.4 ± 0.1 cells/field vs. 0.9 ± 0.1 cells/field, p = 0.003. Apoptosis was significantly increased at day 14 after SD (0.53 ± 0.06 TUNEL+ cells/field compared to controls (0.19 ± 0.03 TUNEL+ cells/field p<0.001 and at 21-d after SD (SD mice 0.53±0.15 TUNEL+ cells/field; p = 0.035. At day 0, IGF-1R expression showed a statistically significant reduction in SD animals (64.6 ± 12.2 units when compared to the control group (102.0 ± 9.8 units; p = 0.043. However, no statistically significant differences were found at day 14 and 21 after SD. In conclusion, a single exposition to SD for 72-h can induce deleterious effects that persist for at least three weeks. These changes are characterized by spatial memory impairment, reduction in the number of hippocampal BrdU+ cells and persistent apoptosis rate. In contrast, changes IGF-1R expression appears to be a transient

  16. 工作记忆和长时记忆共享信息表征的ERP证据%Common Representations between Working Memory and Long-term Memory: Evidence from Event-Related Potentials

    刘兆敏; 郭春彦

    2013-01-01

    Human memory can be characterized as an elaborate network of stored representations. Researchers propose that both working memory (WM) and long-term memory (LTM) utilize same representations, and the representations they activate are in diverse patterns. So the similarity and coherence between WM and LTM are emphasized in the activation-based model, and the priming effect of LTM on WM and vice versa should be both found. By simultaneously recording event-related potentials (ERPs), the present study aimed to investigate two long-term semantic priming effects to illustrate the common representations involved in WM and LTM. Fifteen college students (mean age=20.33±1.91; 7 male) participated in the experiment. The participants were all right-hand, had normal or corrected-to-normal vision and had no neurological or psychological disorders. Each participant signed a consent form prior to experiment and was paid after experiment. We combined a WM component (short-term verbal encoding) and a LTM component (category comparison) into one task, so that WM and LTM processing could be concurrently investigated. LTM priming on WM was manipulated by asking participants to learn before short-term verbal encoding, and the priming effect of WM on related LTM should be found in category comparison. Results revealed two long-term semantic priming effects in behavior data and ERPs. The first effect was found in short-term encoding phase, which was reflected as the priming of LTM on WM. Compared with new targets in WM, the reaction time of studied targets was shorter. They elicitedearlier N2 and P3, and they also decreased N2 amplitude. These may index the so-called neural priming (or repetition suppression) of scalp potentials. However, there was no difference between new and studied distractors in WM. Furthermore, the neural priming of WM on LTM also exhibited in category comparison. Specific contents, which were formerly concerned or ignored in short-term encoding phase, led

  17. Rapid Eye Movement Sleep Deprivation Produces Long-Term Detrimental Effects in Spatial Memory and Modifies the Cellular Composition of the Subgranular Zone

    Soto-Rodriguez, Sofia; Lopez-Armas, Gabriela; Luquin, Sonia; Ramos-Zuñiga, Rodrigo; Jauregui-Huerta, Fernando; Gonzalez-Perez, Oscar; Gonzalez-Castañeda, Rocio E.

    2016-01-01

    Sleep deprivation (SD) affects spatial memory and proliferation in the dentate gyrus. It is unknown whether these deleterious effects persist in the long run. The aim of this study was to evaluate the proliferation, differentiation and maturation of neural progenitors as well as spatial memory 21 days after suffering SD. Sixty-day old male Balb/C mice were exposed to 72-h REM-SD. Spatial memory, cell fate, apoptosis and expression levels of insulin-like growth factor 1 receptor (IGF-1R) were evaluated in the hippocampus at 0, 14, and 21 days after SD or control conditions. After 21-days recovery period, memory performance was assessed with the Barnes maze, we found a significant memory impairment in SD mice vs. control (94.0 ± 10.2 s vs. 25.2 ± 4.5 s; p < 0.001). The number of BrdU+ cells was significantly decreased in the SD groups at day 14 (controls = 1.6 ± 0.1 vs. SD mice = 1.2 ± 0.1 cells/field; p = 0.001) and at day 21 (controls = 0.2 ± 0.03 vs. SD mice = 0.1 ± 0.02 cells/field; p < 0.001). A statistically significant decrease was observed in neuronal differentiation (1.4 ± 0.1 cells/field vs. 0.9 ± 0.1 cells/field, p = 0.003). Apoptosis was significantly increased at day 14 after SD (0.53 ± 0.06 TUNEL+ cells/field) compared to controls (0.19 ± 0.03 TUNEL+ cells/field p < 0.001) and at 21-days after SD (SD mice 0.53 ± 0.15 TUNEL+ cells/field; p = 0.035). At day 0, IGF-1R expression showed a statistically significant reduction in SD animals (64.6 ± 12.2 units) when compared to the control group (102.0 ± 9.8 units; p = 0.043). However, no statistically significant differences were found at days 14 and 21 after SD. In conclusion, a single exposition to SD for 72-h can induce deleterious effects that persist for at least 3 weeks. These changes are characterized by spatial memory impairment, reduction in the number of hippocampal BrdU+ cells and persistent apoptosis rate. In contrast, changes IGF-1R expression appears to be a transient event

  18. Beneficial Effects of Tianeptine on Hippocampus-Dependent Long-Term Memory and Stress-Induced Alterations of Brain Structure and Function

    Carmen Muñoz

    2010-10-01

    Full Text Available Tianeptine is a well-described antidepressant which has been shown to prevent stress from producing deleterious effects on brain structure and function. Preclinical studies have shown that tianeptine blocks stress-induced alterations of neuronal morphology and synaptic plasticity. Moreover, tianeptine prevents stress from impairing learning and memory, and, importantly, demonstrates memory-enhancing properties in the absence of stress. Recent research has indicated that tianeptine works by normalizing glutamatergic neurotransmission, a mechanism of action that may underlie its effectiveness as an antidepressant. These findings emphasize the value in focusing on the mechanisms of action of tianeptine, and specifically, the glutamatergic system, in the development of novel pharmacotherapeutic strategies in the treatment of depression.

  19. Effects of d-amphetamine on short- and long-term memory in spontaneously hypertensive, Wistar-Kyoto and Sprague-Dawley rats.

    Meneses, A; Ponce-Lopez, T; Tellez, R; Gonzalez, R; Castillo, C; Gasbarri, A

    2011-01-01

    Diverse studies indicate that the attention deficit hyperactivity disorder (ADHD) is associated with alterations in encoding processes, including working or short-term memory. Some ADHD dysfunctional domains are reflected in the spontaneously hypertensive rat (SHR). Here SHR-saline group showed significantly poor STM and LTM relative to SD and WKY saline rats. SD and WKY rats treated with d-amphetamine displayed better STM and LTM, compared to SD-vehicle, WKY-vehicle or SHR-d-amphetamine groups.

  20. Long-Term Supplementation with Beta Serum Concentrate (BSC), a Complex of Milk Lipids, during Post-Natal Brain Development Improves Memory in Rats.

    Guan, Jian; MacGibbon, Alastair; Fong, Bertram; Zhang, Rong; Liu, Karen; Rowan, Angela; McJarrow, Paul

    2015-06-05

    We have previously reported that the supplementation of ganglioside-enriched complex-milk-lipids improves cognitive function and that a phospholipid-enriched complex-milk-lipid prevents age-related cognitive decline in rats. This current study evaluated the effects of post-natal supplementation of ganglioside- and phospholipid-enriched complex-milk-lipids beta serum concentrate (BSC) on cognitive function in young rats. The diet of male rats was supplemented with either gels formulated BSC (n = 16) or blank gels (n = 16) from post-natal day 10 to day 70. Memory and anxiety-like behaviors were evaluated using the Morris water maze, dark-light boxes, and elevated plus maze tests. Neuroplasticity and white matter were measured using immunohistochemical staining. The overall performance in seven-day acquisition trials was similar between the groups. Compared with the control group, BSC supplementation reduced the latency to the platform during day one of the acquisition tests. Supplementation improved memory by showing reduced latency and improved path efficiency to the platform quadrant, and smaller initial heading error from the platform zone. Supplemented rats showed an increase in striatal dopamine terminals and hippocampal glutamate receptors. Thus BSC supplementation during post-natal brain development improved learning and memory, independent from anxiety. The moderately enhanced neuroplasticity in dopamine and glutamate may be biological changes underlying the improved cognitive function.

  1. Long-Term Supplementation with Beta Serum Concentrate (BSC, a Complex of Milk Lipids, during Post-Natal Brain Development Improves Memory in Rats

    Jian Guan

    2015-06-01

    Full Text Available We have previously reported that the supplementation of ganglioside-enriched complex-milk-lipids improves cognitive function and that a phospholipid-enriched complex-milk-lipid prevents age-related cognitive decline in rats. This current study evaluated the effects of post-natal supplementation of ganglioside- and phospholipid-enriched complex-milk-lipids beta serum concentrate (BSC on cognitive function in young rats. The diet of male rats was supplemented with either gels formulated BSC (n = 16 or blank gels (n = 16 from post-natal day 10 to day 70. Memory and anxiety-like behaviors were evaluated using the Morris water maze, dark–light boxes, and elevated plus maze tests. Neuroplasticity and white matter were measured using immunohistochemical staining. The overall performance in seven-day acquisition trials was similar between the groups. Compared with the control group, BSC supplementation reduced the latency to the platform during day one of the acquisition tests. Supplementation improved memory by showing reduced latency and improved path efficiency to the platform quadrant, and smaller initial heading error from the platform zone. Supplemented rats showed an increase in striatal dopamine terminals and hippocampal glutamate receptors. Thus BSC supplementation during post-natal brain development improved learning and memory, independent from anxiety. The moderately enhanced neuroplasticity in dopamine and glutamate may be biological changes underlying the improved cognitive function.

  2. Long-term urethral catheterisation.

    Turner, Bruce; Dickens, Nicola

    This article discusses long-term urethral catheterisation, focusing on the relevant anatomy and physiology, indications for the procedure, catheter selection and catheter care. It is important that nurses have a good working knowledge of long-term catheterisation as the need for this intervention will increase with the rise in chronic health conditions and the ageing population.

  3. Multimodal assessment of long-term memory recall and reinstatement in a combined cue and context fear conditioning and extinction paradigm in humans.

    Jan Haaker

    Full Text Available Learning to predict danger via associative learning processes is critical for adaptive behaviour. After successful extinction, persisting fear memories often emerge as returning fear. Investigation of return of fear phenomena, e.g. reinstatement, have only recently began and to date, many critical questions with respect to reinstatement in human populations remain unresolved. Few studies have separated experimental phases in time even though increasing evidence shows that allowing for passage of time (and consolidation between experimental phases has a major impact on the results. In addition, studies have relied on a single psychophysiological dimension only (SCRs/SCL or FPS which hampers comparability between different studies that showed both differential or generalized return of fear following a reinstatement manipulation. In 93 participants, we used a multimodal approach (fear-potentiated startle, skin conductance responses, fear ratings to asses fear conditioning (day 1, extinction (day 2 as well as delayed memory recall and reinstatement (day 8 in a paradigm that probed contextual and cued fear intra-individually. Our findings show persistence of conditioning and extinction memory over time and demonstrate that reinstated fear responses were qualitatively different between dependent variables (subjective fear ratings, FPS, SCRs as well as between cued and contextual CSs. While only the arousal-related measurement (SCRs showed increasing reactions following reinstatement to the cued CSs, no evidence of reinstatement was observed for the subjective ratings and fear-related measurement (FPS. In contrast, for contextual CSs, reinstatement was evident as differential and generalized reinstatement in fear ratings as well as generally elevated physiological fear (FPS and arousal (SCRs related measurements to all contextual CSs (generalized non-differential reinstatement. Returning fear after reinstatement likely depends on a variety of variables

  4. Effects of reversible pharmacological shutdown of cerebellar flocculus on the memory of long-term horizontal vestibulo-ocular reflex adaptation in monkeys.

    Anzai, Mari; Kitazawa, Hiromasa; Nagao, Soichi

    2010-11-01

    The adaptation of the horizontal vestibulo-ocular reflex (HVOR) provides an experimental model for motor learning. Two studies, using cats and mice, respectively, have recently suggested pharmacologically that the memory of adaptation is located multiply in the cerebellum and brainstem. Here, we examined the effects of acute cerebellar flocculus shutdown on the adaptation in four monkeys. Two hours of 0.11Hz-10° turntable oscillation while viewing a stationary checked-patterned screen through the left-right reversing prism decreased the HVOR gains by 0.16, and 3 days of prism wearing combined with 2h of daily turntable oscillation decreased the HVOR gains by 0.27. Injections of lidocaine into bilateral flocculi did not affect the nonadapted HVOR gains, but depressed the visual suppression of the HVOR. They recovered the HVOR gains decreased by 2h of training, but very little affected the HVOR gains decreased by previous 2 days of training. Injections of control Ringer's solution did not affect the gains adapted by 2h or 3 days of training. These results are consistent with the previous studies, and suggest that the memory trace of adaptation of the HVOR initially resides in the flocculus but later resides, presumably, in the vestibular nuclei in the monkey.

  5. Enhancement of declarative memory associated with emotional content in a Brazilian sample

    Frank J.E.

    2000-01-01

    Full Text Available Several studies have documented that emotional arousal may enhance long-term memory. This is an adaptation of a paradigm previously used in North American and European samples in investigations of the influence of emotion on long-term retention. A sample of 46 healthy adults of high and low educational levels watched a slide presentation of stories. A randomly assigned group watched a story with an arousing content and another group watched a neutral story. The stories were matched for structure and comprehensibility and the set and order of the 11 slides were the same in both conditions. Immediately after viewing the slide presentation, the participants were asked to rate the emotionality of the narrative. The arousing narrative was rated as being more emotional than the neutral narrative (t (44 = -3.6, P<0.001. Ten days later subjects were asked to remember the story and answer a multiple-choice questionnaire about it. The subjects who watched the arousing story had higher scores in the free recall measure (t (44 = -2.59, P<0.01. There were no differences between groups in the multiple-choice test of recognition memory (t (44 = 0.26. These findings confirm that an emotional arousing content enhances long-term declarative memory and indicate the possibility of applying this instrument to clinical samples of various cultural backgrounds.

  6. Effects of previous physical exercise to chronic stress on long-term aversive memory and oxidative stress in amygdala and hippocampus of rats.

    Dos Santos, Tiago Marcon; Kolling, Janaína; Siebert, Cassiana; Biasibetti, Helena; Bertó, Carolina Gessinger; Grun, Lucas Kich; Dalmaz, Carla; Barbé-Tuana, Florencia María; Wyse, Angela T S

    2017-02-01

    Since stressful situations are considered risk factors for the development of depression and there are few studies evaluating prevention therapies for this disease, in the present study we evaluated the effect of previous physical exercise in animals subjected to chronic variable stress (CVS), an animal model of depression, on behavior tasks. We also investigated some parameters of oxidative stress and Na(+), K(+)-ATPase activity, immunocontent and gene expression of alpha subunits in amygdala and hippocampus of rats. Young male rats were randomized into four study groups (control, exercised, stressed, exercised+stressed). The animals were subjected to controlled exercise treadmill for 20min,three times a week, for two months prior to submission to the CVS (40days). Results show that CVS impaired performance in inhibitory avoidance at 24h and 7days after training session. CVS induced oxidative stress, increasing reactive species, lipoperoxidation and protein damage, and decreasing the activity of antioxidant enzymes. The activity of Na(+), K(+)-ATPase was decreased, but the immunocontents and gene expression of catalytic subunits were not altered. The previous physical exercise was able to improve performance in inhibitory avoidance at 24h after training; additionally, exercise prevented oxidative damage, but was unable to reverse completely the changes observed on the enzymatic activities. Our findings suggest that physical exercise during the developmental period may protect against aversive memory impairment and brain oxidative damage caused by chronic stress exposure later in life.

  7. Persistence of immunologic memory in long-term hemodialysis patients and healthcare workers given hepatitis B vaccine: role of a booster dose on antibody response.

    Peces, R; Laurés, A S

    2001-10-01

    Hepatitis B (HB) vaccine is effective in producing protection against HB virus infection, but the persistence of immunity remains largely unknown. Seventy-six hemodialysis (HD) patients (60 after primary HB vaccination and 16 with natural immunity) and 46 healthcare workers (32 after primary HB vaccination and 14 with natural immunity) were followed up for 10 years to evaluate the persistence of immunity. Ten years after vaccination, the analysis showed a lower seroconversion rate (38 vs. 75%, p < 0.001) in HD patients as compared with healthcare workers. In the follow-up period, the protective immunity developed through HB virus infection also showed a lower seroconversion rate (44 vs. 86%, p < 0.025) in HD patients as compared with healthcare workers. To assess the status of immunologic memory, we administered a booster dose of HB vaccine 3-12 years (mean 6.7 +/- 0.6 years) after primary vaccination in a selected group of 37 HD patients who presented a decline of their antibodies or were nonresponders. In another group of 12 healthcare workers who had a decline of their antibodies, we also administered a booster dose of HB vaccine 5-8 years (mean 5.8 +/- 0.3 years) after primary vaccination. Nineteen of the 37 HD patients (51%) presented an anamnestic response to the booster dose, and 15 of these (40%) were high responders. All of the healthcare workers responded to the booster dose with a high antibody response. We conclude that patients undergoing HD not only have lower rates of immunization to HB than healthy adults, but also that these are frequently transient. Booster doses after a primary course of vaccine are effective in about the half of HD patients who presented a decline of their antibodies or were nonresponders but whether they are necessary is unclear. The majority of healthcare workers continue to have high levels of protective HBs antibody for at least 10 years and routine boosters are not required.

  8. Gratitude in Long Term Care

    Brooke Abrams Sunding

    2015-04-01

    Full Text Available An exploratory study was conducted to examine the effectiveness of a group gratitude intervention with 29 permanent residents at a long term care/skilled nursing facility in improving elder mood, behavior and well- being over a 3 week time period. The sample included individuals diagnosed with dementia, other cognitive impairment, major depressive disorder, insomnia and generalized anxiety disorder. The gratitude intervention consisted of asking elders to share what they are thankful for at the dinner table each day. Measures included the Elder Well Being Scale and The Dinner Rating Scale. On both measures, higher scores indicated better functioning. To test the hypothesis that post treatment elder well-being will be significantly higher than pretreatment elder well-being ratings, a one-way ANOVA was conducted. Post-hoc tests revealed a statistically significant increase in Elder Well Being Scale scores. An ANOVA of comparing Dinner Ratings demonstrated a nonsignificant increase over the 3 week experiment. Implications are discussed.

  9. Analysis of regulatory T-cells and of their naïve and memory-like subsets in long-term treated aviremic HIV+ patients and untreated viremic patients

    L Imberti

    2012-11-01

    Full Text Available Purpose of the study: Although HIV infection impacts the proportion and phenotype of regulatory T-cells (Tregs, discrepant results have been reported depending on the surface markers employed to characterize them and on the patient populations. In addition, the effects of a long-term combined antiretroviral therapy (cART on Treg cells have not been thoroughly documented. Our study investigated the frequency and number of Tregs and their phenotype in two different groups of HIV-infected patients: one aviremic undergoing long-term cART and one viremic naïve to cART showing a similar CD4+ cell count. Methods: Thirty-six HIV+ patients with sustained suppression of plasma viremia (<37 copies/mL on effective cART for more than 6 years and 22 HIV+patients naïve to cART and without clinical signs of opportunistic infections or tumors at the time of study (untreated group were included in the study. Healthy donors (HD were used as control. Flow cytometry on fresh whole blood was used to quantify total Tregs (defined as CD25+CD127low/-CD4+ cells and the following Treg subsets: naïve (CD45RA+CCR7+ Tregs, central-memory like Tregs (CD45RA-CCR7+, TregCM, effector-memory like Tregs (CD45RA-CCR7−, TregEM Statistical comparisons of the percentages and number of Tregs and Treg subpopulations were performed by ANOVA or Kruskal-Wallis test. Analysis of covariance was employed in order to adjust for the effect of the age. The Spearman's test was used to assess correlations. Summary of results: In viremic untreated and aviremic long-term cART-treated patients the percentage and number of the total Treg cells were not different from those of HD. However, the analysis of Treg phenotype showed a marked redistribution of the Treg subpopulations: in the untreated viremic patients, both the percentage and number of the TregCM subset decreased compared to HD and cART-treated patients, whereas only the percentage of naïve Tregs increased. In particular, the percentage

  10. The long-term effect of MECT on memory in patients with schizophrenia%无抽搐电休克治疗对精神分裂症患者记忆的远期影响

    杨楹

    2015-01-01

    Objective To explore the long-term impact of Modified Electric Convulsive Therapy ( MECT ) on memory in patientwithschizophrenia.Methods 40schizophrenicpatientswhohadbeentreatedwithMECTatleast6monthsago(MECT group), 40 schizoprenic patients never treated with MECT (non-MECT group) and 40 healthy controls (control group) were assessed with self-designed subjective memory questionnaire, Matrics Consensus Cognitive Battery ( MCCB) and Word Memory Test ( WMT) .Results Compared with control group, MECT group and non-MECT group showed significantly higher score of PANSS (P<0.05) and significantly lower score of GAF (P<0.05).Scores of digit sequence, spatial span, verbal memory, visual memory, instant recognition, delayed recognition, consistency, subjective memory assessment in MECT group and non-MECT group were significantly lower than those in control group (P<0.05).Scores of all above-mentioned tests except visual memory in MECT group were significantly lower than those in non-MECT group (P<0.05).Conclusion MECT may has long-term negative effect on the mnemonic function in patients with schizophrenia.%目的:探讨无抽搐电休克治疗( MECT)对精神分裂症患者记忆的远期影响。方法选取至少6个月前接受过MECT的精神分裂症患者40例为MECT组,从未接受过MECT的精神分裂症患者40例为非MECT组,健康人群40例为对照组,采用自编的主观记忆评估问卷、认知功能成套测验( MCCB)及词汇记忆测验视觉版( WMT)进行评估。结果MECT组和非MECT组PANSS评分高于对照组(P<0.05),GAF评分低于对照组(P<0.05);MECT组和非MECT组数字序列、空间广度、言语记忆、视觉记忆、即时再认、延迟再认、一致性、主观记忆评估评分均低于对照组(P<0.05),除视觉记忆得分外,MECT组上述各项评分低于非MECT组(P<0.05)。结论 MECT可能对精神分裂症患者的记忆功能有远期影响。

  11. Prophylactic Subacute Administration of Zinc Increases CCL2, CCR2, FGF2, and IGF-1 Expression and Prevents the Long-Term Memory Loss in a Rat Model of Cerebral Hypoxia-Ischemia

    Victor Manuel Blanco-Alvarez

    2015-01-01

    Full Text Available Prophylactic subacute administration of zinc decreases lipoperoxidation and cell death following a transient cerebral hypoxia-ischemia, thus suggesting neuroprotective and preconditioning effects. Chemokines and growth factors are also involved in the neuroprotective effect in hypoxia-ischemia. We explored whether zinc prevents the cerebral cortex-hippocampus injury through regulation of CCL2, CCR2, FGF2, and IGF-1 expression following a 10 min of common carotid artery occlusion (CCAO. Male rats were grouped as follows: (1 Zn96h, rats injected with ZnCl2 (one dose every 24 h during four days; (2 Zn96h + CCAO, rats treated with ZnCl2 before CCAO; (3 CCAO, rats with CCAO only; (4 Sham group, rats with mock CCAO; and (5 untreated rats. The cerebral cortex-hippocampus was dissected at different times before and after CCAO. CCL2/CCR2, FGF2, and IGF-1 expression was assessed by RT-PCR and ELISA. Learning in Morris Water Maze was achieved by daily training during 5 days. Long-term memory was evaluated on day 7 after learning. Subacute administration of zinc increased expression of CCL2, CCR2, FGF2, and IGF-1 in the early and late phases of postreperfusion and prevented the CCAO-induced memory loss in the rat. These results might be explained by the induction of neural plasticity because of the expression of CCL2 and growth factors.

  12. Prophylactic Subacute Administration of Zinc Increases CCL2, CCR2, FGF2, and IGF-1 Expression and Prevents the Long-Term Memory Loss in a Rat Model of Cerebral Hypoxia-Ischemia

    Blanco-Alvarez, Victor Manuel; Soto-Rodriguez, Guadalupe; Gonzalez-Barrios, Juan Antonio; Martinez-Fong, Daniel; Brambila, Eduardo; Torres-Soto, Maricela; Aguilar-Peralta, Ana Karina; Gonzalez-Vazquez, Alejandro; Tomás-Sanchez, Constantino; Limón, I. Daniel; Eguibar, Jose R.; Ugarte, Araceli; Hernandez-Castillo, Jeanett; Leon-Chavez, Bertha Alicia

    2015-01-01

    Prophylactic subacute administration of zinc decreases lipoperoxidation and cell death following a transient cerebral hypoxia-ischemia, thus suggesting neuroprotective and preconditioning effects. Chemokines and growth factors are also involved in the neuroprotective effect in hypoxia-ischemia. We explored whether zinc prevents the cerebral cortex-hippocampus injury through regulation of CCL2, CCR2, FGF2, and IGF-1 expression following a 10 min of common carotid artery occlusion (CCAO). Male rats were grouped as follows: (1) Zn96h, rats injected with ZnCl2 (one dose every 24 h during four days); (2) Zn96h + CCAO, rats treated with ZnCl2 before CCAO; (3) CCAO, rats with CCAO only; (4) Sham group, rats with mock CCAO; and (5) untreated rats. The cerebral cortex-hippocampus was dissected at different times before and after CCAO. CCL2/CCR2, FGF2, and IGF-1 expression was assessed by RT-PCR and ELISA. Learning in Morris Water Maze was achieved by daily training during 5 days. Long-term memory was evaluated on day 7 after learning. Subacute administration of zinc increased expression of CCL2, CCR2, FGF2, and IGF-1 in the early and late phases of postreperfusion and prevented the CCAO-induced memory loss in the rat. These results might be explained by the induction of neural plasticity because of the expression of CCL2 and growth factors. PMID:26355725

  13. 长期电磁辐射暴露对大鼠学习记忆能力的影响%Effects of Long-Term Electromagnetic Radiations on Learning and Memory Function of Rats

    田勇浩; 陈素; 郝冬梅; 刘向明; 吴水才

    2011-01-01

    Objective To study the effects of long-term electromagnetic radiations on learning and memory function of rats. Methods After successfully trained in the 8-Arm maze,all rats were randomly divided into control group and radiation group. Then the radiation group was administered with 10 mW/cm2 microwave exposure for eight consecutive weeks (six hours every day). Every week their learning and memory abilities were tested by 8-Arm maze. After eight weeks,chemical colorimetric assay was used to detect the acetylcholinesterase activity of all the rats according to kit instructions. Results From the 1st week to the 6th week, the normalized time, reference memory error and working memory error of the radiation group in the maze test increased compared to those of control group (P<0.05) , but from the 7th week to the 8th week they had no difference from the control group. After eight weeks,the brain acetylcholinesterase activity of control group and radiation group were (1.08± 0.13) and (1.01±0.15)U/mg Pro respectively. There had no differences between the two groups. Conclusion After 10 mW/cm2 electromagnetic radiation, the capability of learning, spatial reference memory and working memory could be attenuated in the short term. But the effect of long-term electromagnetic radiation may be limited.%目的 研究长期电磁辐射对大鼠学习记忆能力的影响.方法 将通过八臂迷宫训练的16只健康成年清洁级Wistar雄性大鼠随机分为辐射组和对照组,每组8只.辐射组进行功率密度为10 mW/cm2的电磁辐射,每天6h,每周6d,连续8周.每周采用八臂迷宫实验测定大鼠的学习记忆能力.8周后,测定大鼠脑组织乙酰胆碱酯酶活力.结果 辐射组大鼠每次迷宫实验耗时标准化数值、参考记忆错误次数以及工作记忆错误次数在第1~6周明显多于对照组大鼠(P<0.05),但第7、8周辐射组大鼠与对照组大鼠在迷宫实验耗时标准化数值、参考记忆错误次数以及

  14. The long term characteristics of greenschist

    Jang, Bo-An

    2016-04-01

    The greenschist in the Jinping II Hydropower Station in southwest China exhibits continuous creep behaviour because of the geological conditions in the region. This phenomenon illustrates the time-dependent deformation and progressive damage that occurs after excavation. In this study, the responses of greenschist to stress over time were determined in a series of laboratory tests on samples collected from the access tunnel walls at the construction site. The results showed that the greenschist presented time-dependent behaviour under long-term loading. The samples generally experienced two stages: transient creep and steady creep, but no accelerating creep. The periods of transient creep and steady creep increased with increasing stress levels. The long-term strength of the greenschist was identified based on the variation of creep strain and creep rate. The ratio of long-term strength to conventional strength was around 80% and did not vary much with confining pressures. A quantitative method for predicting the failure period of greenschist, based on analysis of the stress-strain curve, is presented and implemented. At a confining pressure of 40 MPa, greenschist was predicted to fail in 5000 days under a stress of 290 MPa and to fail in 85 days under the stress of 320 MPa, indicating that the long-term strength identified by the creep rate and creep strain is a reliable estimate.

  15. Nicotine shifts the temporal activation of hippocampal protein kinase A and extracellular signal-regulated kinase 1/2 to enhance long-term, but not short-term, hippocampus-dependent memory.

    Gould, Thomas J; Wilkinson, Derek S; Yildirim, Emre; Poole, Rachel L F; Leach, Prescott T; Simmons, Steven J

    2014-03-01

    Acute nicotine enhances hippocampus-dependent learning through nicotine binding to β2-containing nicotinic acetylcholine receptors (nAChRs), but it is unclear if nicotine is targeting processes involved in short-term memory (STM) leading to a strong long-term memory (LTM) or directly targeting LTM. In addition, the molecular mechanisms involved in the effects of nicotine on learning are unknown. Previous research indicates that protein kinase A (PKA), extracellular signal-regulated kinase 1/2 (ERK1/2), and protein synthesis are crucial for LTM. Therefore, the present study examined the effects of nicotine on STM and LTM and the involvement of PKA, ERK1/2, and protein synthesis in the nicotine-induced enhancement of hippocampus-dependent contextual learning in C57BL/6J mice. The protein synthesis inhibitor anisomycin impaired contextual conditioning assessed at 4 h but not 2 h post-training, delineating time points for STM (2 h) and LTM (4 h and beyond). Nicotine enhanced contextual conditioning at 4, 8, and 24 h but not 2 h post-training, indicating nicotine specifically enhances LTM but not STM. Furthermore, nicotine did not rescue deficits in contextual conditioning produced by anisomycin, suggesting that the nicotine enhancement of contextual conditioning occurs through a protein synthesis-dependent mechanism. In addition, inhibition of dorsal hippocampal PKA activity blocked the effect of acute nicotine on learning, and nicotine shifted the timing of learning-related PKA and ERK1/2 activity in the dorsal and ventral hippocampus. Thus, the present results suggest that nicotine specifically enhances LTM through altering the timing of PKA and ERK1/2 signaling in the hippocampus, and suggests that the timing of PKA and ERK1/2 activity could contribute to the strength of memories.

  16. Estimating the long-term effects of stocking domesticated trout into wild brown trout ( Salmo trutta ) populations : an approach using microsatellite DNA analysis of historical and contemporary samples

    Hansen, Michael Møller

    2002-01-01

    . The study was based on analysis of two historical samples (194556), represented by old scale collections, and seven contemporary samples (1986-2000). In one population historical and contemporary samples were remarkably genetically similar despite more than a decade of intense stocking. Estimation...... equal survival and reproductive performance of wild and domesticated trout. This demonstrates poor performance and low fitness of domesticated trout in the wild. In another population there was a strong genetic contribution from domesticated trout (between 57% and 88% in different samples), both...... in samples from a broodstock thought to represent the indigenous population and in a sample of wild spawners. Survival of domesticated trout and admixture with indigenous fish in the broodstock and subsequent stocking into the river, combined with a low population size of native trout relative to the number...

  17. The Effects of Activation Levels of Visual Long-Term Memory on Visual Short-Term Memory%视觉长时记忆激活度对促进视觉短时记忆的影响

    鲍旭辉; 姬鸣; 黄杰; 何立国; 游旭群

    2014-01-01

    It is a fundamental question that whether visual short-term memory (VSTM) and visual long-term memory (VLTM) are two separate stores or two different states of the same representation. Previous researches focused on whether VSTM could be facilitated by VLTM, however, existing studies on this topic yielded conflicting results. Most neurophysiological or behavioral studies adopted faces as stimuli, and have arrived at the conclusion that VLTM could facilitate VSTM. It ought to be noted that in studies that found no facilitation, the exposure of the experimental materials was not sufficiently to activate VLTM. Therefore, it was hypothesized that only a highly activated VLTM could facilitate VSTM. The purpose of the present study was to investigate the effect of activation level of VLTM on facilitating VSTM within the change-detection paradigm. In Experiment 1, participants were instructed to memorize a study image including 6 geometric figures (6 random shape-color bindings from a pool of eight shapes and eight colors), and then after a random inter-stimulus interval (1, 1.5, or 3 s), either the same image or an image with one shape or color changed was presented, and participants were asked to judge whether they detected a change. In Experiment 2, a total of 8 geometric figures with fixed combinations of color and shape were used to substitute all the random combinations of experiment 1. The experimental procedure and design was identical to experiment 1. One hour after the experiment, participants were asked to participate in a post-experiment to examine whether the study stimuli were stored in VLTM. In Experiment 3, participants were asked to visually study the 8 figures in experiment 2 for a week (at least 10 min a day). Then, they took part in a pre-experiment (the same as the post-experiment in experiment 2) to test whether a highly activated VLTM was obtained. At last, the experimental procedure as described in Experiment 2 was performed. The results showed

  18. Focal radiation therapy combined with 4-1BB activation and CTLA-4 blockade yields long-term survival and a protective antigen-specific memory response in a murine glioma model.

    Zineb Belcaid

    Full Text Available BACKGROUND: Glioblastoma (GBM is the most common malignant brain tumor in adults and is associated with a poor prognosis. Cytotoxic T lymphocyte antigen -4 (CTLA-4 blocking antibodies have demonstrated an ability to generate robust antitumor immune responses against a variety of solid tumors. 4-1BB (CD137 is expressed by activated T lymphocytes and served as a co-stimulatory signal, which promotes cytotoxic function. Here, we evaluate a combination immunotherapy regimen involving 4-1BB activation, CTLA-4 blockade, and focal radiation therapy in an immune-competent intracranial GBM model. METHODS: GL261-luciferace cells were stereotactically implanted in the striatum of C57BL/6 mice. Mice were treated with a triple therapy regimen consisted of 4-1BB agonist antibodies, CTLA-4 blocking antibodies, and focal radiation therapy using a small animal radiation research platform and mice were followed for survival. Numbers of brain-infiltrating lymphocytes were analyzed by FACS analysis. CD4 or CD8 depleting antibodies were administered to determine the relative contribution of T helper and cytotoxic T cells in this regimen. To evaluate the ability of this immunotherapy to generate an antigen-specific memory response, long-term survivors were re-challenged with GL261 glioma en B16 melanoma flank tumors. RESULTS: Mice treated with triple therapy had increased survival compared to mice treated with focal radiation therapy and immunotherapy with 4-1BB activation and CTLA-4 blockade. Animals treated with triple therapy exhibited at least 50% long-term tumor free survival. Treatment with triple therapy resulted in a higher density of CD4+ and CD8+ tumor infiltrating lymphocytes. Mechanistically, depletion of CD4+ T cells abrogated the antitumor efficacy of triple therapy, while depletion of CD8+ T cells had no effect on the treatment response. CONCLUSION: Combination therapy with 4-1BB activation and CTLA-4 blockade in the setting of focal radiation therapy

  19. Potential groundwater sampling sites for installation of a well network for long-term monitoring of agricultural chemicals in the High Plains Aquifer, Colorado

    U.S. Geological Survey, Department of the Interior — These data are in support of report DS 456 (Arnold and others, 2009). This dataset includes 90 potential groundwater sampling sites randomly generated using...

  20. Long-Term Dynamics of Autonomous Fractional Differential Equations

    Liu, Tao; Xu, Wei; Xu, Yong; Han, Qun

    This paper aims to investigate long-term dynamic behaviors of autonomous fractional differential equations with effective numerical method. The long-term dynamic behaviors predict where systems are heading after long-term evolution. We make some modification and transplant cell mapping methods to autonomous fractional differential equations. The mapping time duration of cell mapping is enlarged to deal with the long memory effect. Three illustrative examples, i.e. fractional Lotka-Volterra equation, fractional van der Pol oscillator and fractional Duffing equation, are studied with our revised generalized cell mapping method. We obtain long-term dynamics, such as attractors, basins of attraction, and saddles. Compared with some existing stability and numerical results, the validity of our method is verified. Furthermore, we find that the fractional order has its effect on the long-term dynamics of autonomous fractional differential equations.

  1. Long-term sampling of CO2 from waste-to-energy plants: 14C determination methodology, data variation and uncertainty

    Fuglsang, Karsten; Pedersen, Niels Hald; Larsen, Anna Warberg;

    2014-01-01

    emission of fossil CO2 from waste-to-energy plants can be monitored according to carbon trading schemes and renewable energy certificates. Weekly and monthly measurements were performed at five Danish waste incinerators. Significant variations between fractions of biogenic CO2 emitted were observed......, not only over time, but also between plants. From the results of monthly samples at one plant, the annual mean fraction of biogenic CO2 was found to be 69% of the total annual CO2 emissions. From weekly samples, taken every 3 months at the five plants, significant seasonal variations in biogenic CO2...

  2. Long-Term Physical and Mental Health Consequences of Childhood Physical Abuse: Results from a Large Population-Based Sample of Men and Women

    Springer, Kristen W.; Sheridan, Jennifer; Kuo, Daphne; Carnes, Molly

    2007-01-01

    Objective: Child maltreatment has been linked to negative adult health outcomes; however, much past research includes only clinical samples of women, focuses exclusively on sexual abuse and/or fails to control for family background and childhood characteristics, both potential confounders. Further research is needed to obtain accurate,…

  3. Stimulation of 5-HT1A, 5-HT1B, 5-HT2A/2C, 5-HT3 and 5-HT4 receptors or 5-HT uptake inhibition: short- and long-term memory.

    Meneses, Alfredo

    2007-11-22

    In order to determine whether short- (STM) and long-term memory (LTM) function in serial or parallel manner, serotonin (5-hydroxtryptamine, 5-HT) receptor agonists were tested in autoshaping task. Results show that control-vehicle animals were modestly but significantly mastering the autoshaping task as illustrated by memory scores between STM and LTM. Thus, post-training administration of 8-OHDPAT (agonist for 5-HT(1A/7) receptors) only at 0.250 and 0.500 mg/kg impaired both STM and LTM. CGS12066 (agonist for 5-HT(1B)) produced biphasic affects, at 5.0 mg/kg impaired STM but at 1.0 and 10.0 mg/kg, respectively, improved or impaired LTM. DOI (agonist for 5-HT(2A/2C) receptors) dose-dependently impaired STM and, at 10.0 mg/kg only impaired LTM. Both, STM and LTM were impaired by either mCPP (mainly agonist for 5-HT(2C) receptors) or mesulergine (mainly antagonist for 5-HT(2C) receptors) lower dose. The 5-HT(3) agonist mCPBG at 1.0 impaired STM and its higher dose impaired both STM and LTM. RS67333 (partial agonist for 5-HT(4) receptors), at 5.0 and 10.0 mg/kg facilitated both STM and LTM. The higher dose of fluoxetine (a 5-HT uptake inhibitor) improved both STM and LTM. Using as head-pokes during CS as an indirect measure of food-intake showed that of 30 memory changes, 21 of these were unrelated to the former. While some STM or LTM impairments can be attributed to decrements in food-intake, but not memory changes (either increase or decreases) produced by 8-OHDPAT, CGS12066, RS67333 or fluoxetine. Except for animals treated with DOI, mCPBG or fluoxetine, other groups treated with 5-HT agonists 6 h following autoshaping training showed similar LTM and unmodified CS-head-pokes scores.

  4. Sleep facilitates long-term face adaptation.

    Ditye, Thomas; Javadi, Amir Homayoun; Carbon, Claus-Christian; Walsh, Vincent

    2013-10-22

    Adaptation is an automatic neural mechanism supporting the optimization of visual processing on the basis of previous experiences. While the short-term effects of adaptation on behaviour and physiology have been studied extensively, perceptual long-term changes associated with adaptation are still poorly understood. Here, we show that the integration of adaptation-dependent long-term shifts in neural function is facilitated by sleep. Perceptual shifts induced by adaptation to a distorted image of a famous person were larger in a group of participants who had slept (experiment 1) or merely napped for 90 min (experiment 2) during the interval between adaptation and test compared with controls who stayed awake. Participants' individual rapid eye movement sleep duration predicted the size of post-sleep behavioural adaptation effects. Our data suggest that sleep prevented decay of adaptation in a way that is qualitatively different from the effects of reduced visual interference known as 'storage'. In the light of the well-established link between sleep and memory consolidation, our findings link the perceptual mechanisms of sensory adaptation--which are usually not considered to play a relevant role in mnemonic processes--with learning and memory, and at the same time reveal a new function of sleep in cognition.

  5. Enhanced Long-Term and Impaired Short-Term Spatial Memory in GluA1 AMPA Receptor Subunit Knockout Mice: Evidence for a Dual-Process Memory Model

    Sanderson, David J.; Good, Mark A.; Skelton, Kathryn; Sprengel, Rolf; Seeburg, Peter H.; Rawlins, J. Nicholas P.; Bannerman, David M.

    2009-01-01

    The GluA1 AMPA receptor subunit is a key mediator of hippocampal synaptic plasticity and is especially important for a rapidly-induced, short-lasting form of potentiation. GluA1 gene deletion impairs hippocampus-dependent, spatial working memory, but spares hippocampus-dependent spatial reference memory. These findings may reflect the necessity of…

  6. Comparison of microbial community compositions of injection and production well samples in a long-term water-flooded petroleum reservoir.

    Ren, Hong-Yan; Zhang, Xiao-Jun; Song, Zhi-yong; Rupert, Wieger; Gao, Guang-Jun; Guo, Sheng-xue; Zhao, Li-Ping

    2011-01-01

    Water flooding plays an important role in recovering oil from depleted petroleum reservoirs. Exactly how the microbial communities of production wells are affected by microorganisms introduced with injected water has previously not been adequately studied. Using denaturing gradient gel electrophoresis (DGGE) approach and 16S rRNA gene clone library analysis, the comparison of microbial communities is carried out between one injection water and two production waters collected from a working block of the water-flooded Gudao petroleum reservoir located in the Yellow River Delta. DGGE fingerprints showed that the similarities of the bacterial communities between the injection water and production waters were lower than between the two production waters. It was also observed that the archaeal composition among these three samples showed no significant difference. Analysis of the 16S rRNA gene clone libraries showed that the dominant groups within the injection water were Betaproteobacteria, Gammaproteobacteria and Methanomicrobia, while the dominant groups in the production waters were Gammaproteobacteria and Methanobacteria. Only 2 out of 54 bacterial operational taxonomic units (OTUs) and 5 out of 17 archaeal OTUs in the injection water were detected in the production waters, indicating that most of the microorganisms introduced by the injection water may not survive to be detected in the production waters. Additionally, there were 55.6% and 82.6% unique OTUs in the two production waters respectively, suggesting that each production well has its specific microbial composition, despite both wells being flooded with the same injection water.

  7. Long-term consequences of membership in trajectory groups of delinquent behavior in an urban sample: violence, drug use, interpersonal, and neighborhood attributes.

    Brook, Judith S; Lee, Jung Yeon; Finch, Stephen J; Brown, Elaine N; Brook, David W

    2013-01-01

    Research on stability and change in delinquent behavior over time has important implications for both the individual and the criminal justice system. The present research looks at this issue by examining the associations between the trajectories of delinquent behavior in adolescence and adult functioning. Data for the present study are from a four-wave longitudinal study of African American and Hispanic participants. Participants provided information at mean ages 14, 19, 24, and 29. We used growth mixture modeling to extract trajectory groups of delinquent behavior in adolescence and young adulthood. Regression analyses were conducted to examine whether memberships in the trajectory groups of delinquent behavior from mean age 14 to mean age 24 were associated with violence, substance abuse and dependence, partner discord, peer substance use, and residence in a high-crime neighborhood at mean age 29 when compared with the reference trajectory group of participants with low or no delinquent behavior. Four trajectory groups of delinquent behavior were identified: the no/low, the decreasing, the moderate, and the high persistent trajectory groups. Memberships in the trajectory groups were significantly correlated with variations in adult functioning. Memberships in some trajectory groups of delinquent behavior are significant predictors of later violent behavior, substance abuse and dependence, partner discord, peer substance use, and residence in a high-crime neighborhood. The findings reinforce the importance of investing in interventions to address different patterns of delinquent behavior. Findings are discussed in relation to previous investigations with non-Hispanic White samples.

  8. Long term stability of power systems

    Kundur, P.; Gao, B. [Powertech Labs. Inc., Surrey, BC (Canada)

    1994-12-31

    Power system long term stability is still a developing subject. In this paper we provide our perspectives and experiences related to long term stability. The paper begins with the description of the nature of the long term stability problem, followed by the discussion of issues related to the modeling and solution techniques of tools for long term stability analysis. Cases studies are presented to illustrate the voltage stability aspect and plant dynamics aspect of long term stability. (author) 20 refs., 11 figs.

  9. 热射病对大鼠空间学习记忆能力远期损害的研究%Long-term Impairment of Spatial Learning and Memory in Rats after Heat Stroke

    张云; 万明胜; 董会; 吴士文

    2016-01-01

    目的:比较热射病大鼠不同阶段的空间学习记忆能力,探讨其远期影响。方法 Sprague-Dawley大鼠42只,建立热射病大鼠模型,将造模成功后的大鼠随机分为热射病7 d组(HS7,n=21)和热射病21 d组(HS21,n=21);另取18只大鼠麻醉后行股动脉插管作为手术对照组(Sham,n=18)。3组分别于造模后7 d、21 d行Morris水迷宫实验5 d,记录逃避潜伏期,跨越平台的次数和目标象限停留时间。结果逃避潜伏期各个时间点HS7组均较Sham组延长(P0.05)。结论热射病大鼠空间学习记忆障碍在发病7d后最严重,并可遗留远期损害。%Objective To compare the spatial learning and memory function of heat stroke rats in different periods, to explore the long-term impairment. Methods 42 Sprague-Dawley rats were randomly divided into heat stroke 7 days group (HS7, n=21), heat stroke 21 days group (HS21, n=21), and another 18 rats were performed femoral artery intubation as surgery control group (sham, n=18). They were tested with Morris water maze 7 days and 21 days after modeling respectively for 5 days. The escaping latency, the frequency of crossing the platform area and the duration in the target quadrant were recorded. Results Compared with the sham group, the escaping latency prolonged in HS7 group in all the time (P0.05). Conclusion The impairment of spatial learning and memory is the most seriously 7 days after heat stroke in rats, and it may remain for long time.

  10. Three-year-olds’ memory for a person met only once at the age of 12 months: Very long-term memory revealed by a late-manifesting novelty preference

    Kingo, Osman Skjold; Staugaard, Søren Risløv; Krøjgaard, Peter

    2014-01-01

    This study examined three-year-olds’ verbal and non-verbal memory for a person met only once after a 28 month interval. Children in the Test group (N=50) had participated in an earlier experiment at our lab at the age of 12 months where they met one of two possible experimenters. At this past event...

  11. CYP2B6*6 and CYP2B6*18 Predict Long-Term Efavirenz Exposure Measured in Hair Samples in HIV-Positive South African Women.

    Röhrich, Carola R; Drögemöller, Britt I; Ikediobi, Ogechi; van der Merwe, Lize; Grobbelaar, Nelis; Wright, Galen E B; McGregor, Nathaniel; Warnich, Louise

    2016-06-01

    Long-term exposure to efavirenz (EFV) measured in hair samples may predict response to antiretroviral treatment (ART). Polymorphisms in CYP2B6 are known to alter EFV levels. The aim of this study was to assess the relationship between CYP2B6 genotype, EFV levels measured in hair, and virological outcomes on ART in a real-world setting. We measured EFV levels in hair from HIV-positive South African females who had been receiving EFV-based treatment for at least 3 months from the South African Black (SAB) (n = 81) and Cape Mixed Ancestry (CMA) (n = 53) populations. Common genetic variation in CYP2B6 was determined in 15 individuals from each population using bidirectional Sanger sequencing. Prioritized variants (n = 16) were subsequently genotyped in the entire patient cohort (n = 134). The predictive value of EFV levels in hair and selected variants in CYP2B6 on virological treatment outcomes was assessed. Previously described alleles (CYP2B6*2, CYP2B6*5, CYP2B6*6, CYP2B6*17, and CYP2B6*18), as well as two novel alleles (CYP2B6*31 and CYP2B6*32), were detected in this study. Compared to noncarriers, individuals homozygous for CYP2B6*6 had ∼109% increased EFV levels in hair (p = .016) and CYP2B6*18 heterozygotes demonstrated 82% higher EFV hair levels (p = .0006). This study confirmed that alleles affecting CYP2B6 metabolism and subsequent EFV exposure are present at significant frequencies in both the SAB and CMA populations. Furthermore, this study demonstrated that the use of hair samples for testing EFV concentrations may be a useful tool in determining long-term drug exposure in resource-limited countries.

  12. Asthma Medicines: Long-Term Control

    ... Size Email Print Share Asthma Medicines: Long-term Control Page Content Article Body Corticosteroids Synthetic versions of ... form, they are used exclusively for long-term control; they are not very effective for acute symptoms. ...

  13. Physiological, Molecular and Genetic Mechanisms of Long-Term Habituation

    Calin-Jageman, Robert J

    2009-09-12

    Work funded on this grant has explored the mechanisms of long-term habituation, a ubiquitous form of learning that plays a key role in basic cognitive functioning. Specifically, behavioral, physiological, and molecular mechanisms of habituation have been explored using a simple model system, the tail-elicited siphon-withdrawal reflex (T-SWR) in the marine mollusk Aplysia californica. Substantial progress has been made on the first and third aims, providing some fundamental insights into the mechanisms by which memories are stored. We have characterized the physiological correlates of short- and long-term habituation. We found that short-term habituation is accompanied by a robust sensory adaptation, whereas long-term habituation is accompanied by alterations in sensory and interneuron synaptic efficacy. Thus, our data indicates memories can be shifted between different sites in a neural network as they are consolidated from short to long term. At the molecular level, we have accomplished microarray analysis comparing gene expression in both habituated and control ganglia. We have identified a network of putatively regulated transcripts that seems particularly targeted towards synaptic changes (e.g. SNAP25, calmodulin) . We are now beginning additional work to confirm regulation of these transcripts and build a more detailed understanding of the cascade of molecular events leading to the permanent storage of long-term memories. On the third aim, we have fostered a nascent neuroscience program via a variety of successful initiatives. We have funded over 11 undergraduate neuroscience scholars, several of whom have been recognized at national and regional levels for their research. We have also conducted a pioneering summer research program for community college students which is helping enhance access of underrepresented groups to life science careers. Despite minimal progress on the second aim, this project has provided a) novel insight into the network mechanisms by

  14. HOME LONG-TERM CARE IN POLAND

    Ewa Kułagowska

    2011-06-01

    Full Text Available The considerable proportion of the elderly, the chronically ill and the disabled in community is an economic and organizational challenge for the state social policy. It requires a large, steadily increasing financing from the public funds and creating an optional care model to fulfill the needs of citizens and guarantee high quality services. Development of the long-term care is one of the problems to be solved. This paper presents: – a long-term care forms, organization and tasks; – a role of long-term care but particularly home longterm care to protect health in Poland; – problems related with home long-term care functioning.

  15. Dynamic Updating Process of Readers' Temporal Situation Model: From Short-term Working Memory to Long-term Working Memory%时间情景模型的动态更新:从短时工作记忆到长时工作记忆

    何先友; 杨惠兰; 张维; 赵雪汝; 谢毅

    2015-01-01

    The situation model is a hot topic in current narrative comprehension research. The Event-indexing model proposed by Zwaan, Langson, and Graesser (1995) suggests that readers establish a mental representation of events by tracking them through five dimensions: time, space, characters, causality, and protagonist/object. A large number of previous studies have shown that the temporal dimension plays an important role in constructing the situation model. The Scenario Account (Anderson, 1983) argues that scene provides clues for temporal shifts, but the Strong Iconicity Assumption (Zwaan, 1996) argues that readers update the situation model as soon as temporal shifts appear. In this study, we designed two experiments to resolve the disagreement between the Scenario Account and the Strong Iconicity Assumption. We assume that the Scenario Model and the Strong Iconicity Assumption do not contradict each other due to how the updating of a situation model has a variable processing mode in different stages of memory processing. We designed two experiments to test this hypothesis: Experiment 1 examined the effects of temporal shifts on the updating of the situation model in short-term working memory, and Experiment 2 examined this effect in long-term working memory.In this study, a moving-window technique was used to explore the extent to which temporal shifts (long/short) affect updating of readers' situation model. Experiment 1a and 1b examined whether long temporal shifts or short temporal shifts affected updating of readers' situation model in short-term working memory. A single factor within-subjects design (time shift of a moment after or a day later) was used. We predicted the long temporal shifts (Experiment 1a) would not result in the updating of readers' situation model due to the time limitation and difficulties of processing in short-term memory, but that short temporal shifts (Experiment 1b) would. Experiment 2 further examined the extent to which long temporal

  16. Long-term survival after perforated diverticulitis

    J. Vermeulen (Jan); M.P. Gosselink (Martijn Pieter); W.C.J. Hop (Wim); E. van der Harst (Erwin); B.E. Hansen (Bettina); G.H.H. Mannaerts (Guido); P-P. Coene (Peter Paul); W.F. Weidema (Wibo); J.F. Lange (Johan)

    2011-01-01

    textabstractAim: Short-term survival after emergency surgery for perforated diverticulitis is poor. Less is known about long-term survival. The aims of this study were to evaluate long-term survival after discharge from hospital and to identify factors associated with prognosis. Method: All patients

  17. Virtual Models of Long-Term Care

    Phenice, Lillian A.; Griffore, Robert J.

    2012-01-01

    Nursing homes, assisted living facilities and home-care organizations, use web sites to describe their services to potential consumers. This virtual ethnographic study developed models representing how potential consumers may understand this information using data from web sites of 69 long-term-care providers. The content of long-term-care web…

  18. Planning long-term vegetation studies at landscape scales

    Stohlgren, Thomas J.

    1995-01-01

    Long-term ecological research is receiving more attention now than ever before. Two recent books, Long-term Studies in Ecology: Approaches and Alternatives, edited by Gene Likens (1989), and Long-term Ecological Research: An International Perspective, edited by Paul Risser (1991), prompt the question, “Why are these books so thin?” Except for data from paleoecological, retrospective studies (see below), there are exceptionally few long-term data sets in terrestrial ecology (Strayer et al. 1986; Tilman 1989; this volume). In a sample of 749 papers published in Ecology, Tilman (1989) found that only 1.7% of the studies lasted at least five field seasons. Only one chapter in each of the review books dealt specifically with expanding both the temporal and the spatial scales of ecological research (Berkowitz et al. 1989; Magnuson et al. 1991). Judging by the growing number of landscape-scale long-term studies, however, such as the Long-Term Ecological Research (LTER) Program (Callahan 1991), the U.S. Environmental Protection Agency’s Environmental Monitoring and Assessment Program (EMAP; Palmer et al. 1991), the U.S. Army’s Land Condition-Trend Analysis (LCTA) Program (Diersing et al. 1992), and various agencies’ global change research programs (CEES 1993), there is a growing interest to expand ecological research both temporally and spatially.

  19. Preschool speech intelligibility and vocabulary skills predict long-term speech and language outcomes following cochlear implantation in early childhood.

    Castellanos, Irina; Kronenberger, William G; Beer, Jessica; Henning, Shirley C; Colson, Bethany G; Pisoni, David B

    2014-07-01

    Speech and language measures during grade school predict adolescent speech-language outcomes in children who receive cochlear implants (CIs), but no research has examined whether speech and language functioning at even younger ages is predictive of long-term outcomes in this population. The purpose of this study was to examine whether early preschool measures of speech and language performance predict speech-language functioning in long-term users of CIs. Early measures of speech intelligibility and receptive vocabulary (obtained during preschool ages of 3-6 years) in a sample of 35 prelingually deaf, early-implanted children predicted speech perception, language, and verbal working memory skills up to 18 years later. Age of onset of deafness and age at implantation added additional variance to preschool speech intelligibility in predicting some long-term outcome scores, but the relationship between preschool speech-language skills and later speech-language outcomes was not significantly attenuated by the addition of these hearing history variables. These findings suggest that speech and language development during the preschool years is predictive of long-term speech and language functioning in early-implanted, prelingually deaf children. As a result, measures of speech-language functioning at preschool ages can be used to identify and adjust interventions for very young CI users who may be at long-term risk for suboptimal speech and language outcomes.

  20. 短时工作记忆广度与长时工作记忆技能对态势了解的影响%Effects of Short-term Working Memory Capacity and Long-term Working Memory Skill on Situation Awareness

    傅亚强; 许百华

    2012-01-01

    目的 揭示操作者保持态势了解(态势感知)所依赖的记忆过程,并研究短时工作记忆和长时工作记忆与态势了解之间的关系.方法 在测量熟练受试者与新手受试者的言语与空间工作记忆广度、长时工作记忆技能和态势了解的基础上,建立态势了解对空间和言语工作记忆广度、长时工作记忆技能的分层回归模型.结果 熟练受试者的长时工作记忆技能、空间工作记忆广度以及二者的乘积都能有效地预测态势了解,空间工作记忆广度对态势了解的影响随着长时工作记忆技能的增加而减少.新手受试者的空间和言语工作记忆广度能有效地预测态势了解.结论 短时工作记忆和长时工作记忆在态势了解保持过程中发挥着重要作用,操作者的任务经验越丰富,保持态势了解对短时工作记忆的依赖程度就越弱,对长时工作记忆的依赖程度则越强.%Objective To reveal the memory process involved in the maintenance of situation awareness (SA) and study the relationship between memory (short-term working memory STWM and long-term working memory LTWM) and SA. Methods Verbal working memory capacity, spatial working memory capacity, LTWM skill and SA of skilled and novice subjects were measured. Hierarchical regression model were established to determine the relationship between memory ( spatial and verbal working memory capacities, as well as LTWM skill) and SA. Results Spatial working memory capacity, LTWM skill, and their products of skilled subjects could effectively predict SA. The effect of spatial working memory on SA of skilled subjects would be decreased as their LTWM skill increased. Verbal and spatial working memory capacity of novice subjects could effectively predict SA. Conclusion STWM and LTWM are involved together in the process of maintaining SA and their importance varies as a function of subject style.

  1. Short-Term Plasticity and Long-Term Potentiation in Magnetic Tunnel Junctions: Towards Volatile Synapses

    Sengupta, Abhronil; Roy, Kaushik

    2016-02-01

    Synaptic memory is considered to be the main element responsible for learning and cognition in humans. Although traditionally nonvolatile long-term plasticity changes are implemented in nanoelectronic synapses for neuromorphic applications, recent studies in neuroscience reveal that biological synapses undergo metastable volatile strengthening followed by a long-term strengthening provided that the frequency of the input stimulus is sufficiently high. Such "memory strengthening" and "memory decay" functionalities can potentially lead to adaptive neuromorphic architectures. In this paper, we demonstrate the close resemblance of the magnetization dynamics of a magnetic tunnel junction (MTJ) to short-term plasticity and long-term potentiation observed in biological synapses. We illustrate that, in addition to the magnitude and duration of the input stimulus, the frequency of the stimulus plays a critical role in determining long-term potentiation of the MTJ. Such MTJ synaptic memory arrays can be utilized to create compact, ultrafast, and low-power intelligent neural systems.

  2. Diabetes MILES--Australia (management and impact for long-term empowerment and success: methods and sample characteristics of a national survey of the psychological aspects of living with type 1 or type 2 diabetes in Australian adults

    Speight Jane

    2012-02-01

    Full Text Available Abstract Background Successful management of diabetes requires attention to the behavioural, psychological and social aspects of this progressive condition. The Diabetes MILES (Management and Impact for Long-term Empowerment and Success Study is an international collaborative. Diabetes MILES--Australia, the first Diabetes MILES initiative to be undertaken, was a national survey of adults living with type 1 or type 2 diabetes in Australia. The aim of this study was to gather data that will provide insights into how Australians manage their diabetes, the support they receive and the impact of diabetes on their lives, as well as to use the data to validate new diabetes outcome measures. Methods/design The survey was designed to include a core set of self-report measures, as well as modules specific to diabetes type or management regimens. Other measures or items were included in only half of the surveys. Cognitive debriefing interviews with 20 participants ensured the survey content was relevant and easily understood. In July 2011, the survey was posted to 15,000 adults (aged 18-70 years with type 1 or type 2 diabetes selected randomly from the National Diabetes Services Scheme (NDSS database. An online version of the survey was advertised nationally. A total of 3,338 eligible Australians took part; most (70.4% completed the postal survey. Respondents of both diabetes types and genders, and of all ages, were adequately represented in both the postal and online survey sub-samples. More people with type 2 diabetes than type 1 diabetes took part in Diabetes MILES--Australia (58.8% versus 41.2%. Most respondents spoke English as their main language, were married/in a de facto relationship, had at least a high school education, were occupied in paid work, had an annual household income > $AUS40,000, and lived in metropolitan areas. Discussion A potential limitation of the study is the under-representation of respondents from culturally and

  3. Age, memory type, and the phenomenology of autobiographical memory: findings from an Italian sample.

    Montebarocci, Ornella; Luchetti, Martina; Sutin, Angelina R

    2014-01-01

    The present research explored differences in phenomenology between two types of memories, a general self-defining memory and an earliest childhood memory. A sample of 76 Italian participants were selected and categorised into two age groups: 20-30 years and 31-40 years. The Memory Experiences Questionnaire (MEQ) was administered, taking note of latency and duration times of the narratives. Consistent with the literature, the self-defining memory differed significantly from the earliest childhood memory in terms of phenomenology, with the recency of the memory associated with more intense phenomenological experience. The self-defining memory took longer to retrieve and narrate than the earliest childhood memory. Meaningful differences also emerged between the two age groups: Participants in their 30s rated their self-defining memory as more vivid, coherent, and accessible than participants in their 20s. According to latency findings, these differences suggest an expanded period of identity consolidation for younger adults. Further applications of the MEQ should be carried out to replicate these results with other samples of young adults.

  4. Long-term outcome of meniscectomy

    Roos, Ewa M.; Ostenberg, A; Roos, H;

    2001-01-01

    To describe the long-term influence of meniscectomy on pain, functional limitations, and muscular performance. To assess the effects of radiographic osteoarthritis (OA), gender and age on these outcomes in patients with meniscectomy....

  5. Long Term Care Minimum Data Set (MDS)

    U.S. Department of Health & Human Services — The Long-Term Care Minimum Data Set (MDS) is a standardized, primary screening and assessment tool of health status that forms the foundation of the comprehensive...

  6. Long-Term Care Ombudsman Program

    ... Strategic Plan Federal Initiatives Career Opportunities Contact Us Administration on Aging (AoA) Long-Term Care Ombudsman Program ( ... Prevention HIV/AIDS Nutrition Services Oral Health Elder Justice & Adult Protective Services Elder Justice Coordinating Council Prevention ...

  7. Long-Term Ownership by Industrial Foundations

    Børsting, Christa Winther; Kuhn, Johan Moritz; Poulsen, Thomas

    2016-01-01

    Short-termism has become a serious concern for businesses and policy makers and this has inspired a search for governance arrangement to promote long term decision making. In this paper we study a particularly long-term ownership structure, which is fairly common in Northern Europe, particularly...... in Denmark. Industrial foundations are independent legal entities without owners or members typically with the dual objective of preserving the company and using excess profits for charity. We use a unique Danish data set to examine the governance of foundation-owned companies. We show that they are long-term...... in several respects. Foundations hold on to their shares for longer. Foundation-owned companies replace managers less frequently. They have more conservative capital structures with less leverage. Their companies survive longer. Their business decisions appear to be more long term. This paper supports...

  8. Pituitary diseases : long-term clinical consequences

    Klaauw, Agatha Apolonia van der

    2008-01-01

    This thesis describes various studies during the long-term follow-up of patients after treatment for pituitary diseases. The focus of this thesis is acromegaly, growth hormone deficiency, sleep and quality of life. Various aspects are described.

  9. Anticipating Long-Term Stock Market Volatility

    Conrad, Christian; Loch, Karin

    2012-01-01

    We investigate the relationship between long-term U.S. stock market risks and the macroeconomic environment using a two component GARCH-MIDAS model. Our results provide strong evidence in favor of counter-cyclical behavior of long-term stock market volatility. Among the various macro variables in our dataset the term spread, housing starts, corporate profits and the unemployment rate have the highest predictive ability for stock market volatility . While the term spread and housing starts are...

  10. Long-term outcomes after severe shock.

    Pratt, Cristina M; Hirshberg, Eliotte L; Jones, Jason P; Kuttler, Kathryn G; Lanspa, Michael J; Wilson, Emily L; Hopkins, Ramona O; Brown, Samuel M

    2015-02-01

    Severe shock is a life-threatening condition with very high short-term mortality. Whether the long-term outcomes among survivors of severe shock are similar to long-term outcomes of other critical illness survivors is unknown. We therefore sought to assess long-term survival and functional outcomes among 90-day survivors of severe shock and determine whether clinical predictors were associated with outcomes. Seventy-six patients who were alive 90 days after severe shock (received ≥1 μg/kg per minute of norepinephrine equivalent) were eligible for the study. We measured 3-year survival and long-term functional outcomes using the Medical Outcomes Study 36-Item Short-Form Health Survey, the EuroQOL 5-D-3L, the Hospital Anxiety and Depression Scale, the Impact of Event Scale-Revised, and an employment instrument. We also assessed the relationship between in-hospital predictors and long-term outcomes. The mean long-term survival was 5.1 years; 82% (62 of 76) of patients survived, of whom 49 were eligible for follow-up. Patients who died were older than patients who survived. Thirty-six patients completed a telephone interview a mean of 5 years after hospital admission. The patients' Physical Functioning scores were below U.S. population norms (P shock had a high 3-year survival rate. Patients' long-term physical and psychological outcomes were similar to those reported for cohorts of less severely ill intensive care unit survivors. Anxiety and depression were relatively common, but only a few patients had symptoms of posttraumatic stress disorder. This study supports the observation that acute illness severity does not determine long-term outcomes. Even extremely critically ill patients have similar outcomes to general intensive care unit survivor populations.

  11. A long-term, multitrophic level study to assess pulp and paper mill effluent effects on aquatic communities in four US receiving waters: characteristics of the study streams, sample sites, mills, and mill effluents.

    Hall, Timothy J; Ragsdale, Renee L; Arthurs, William J; Ikoma, Joan; Borton, Dennis L; Cook, Diana L

    2009-04-01

    Watershed characteristics, study streams, sample sites, mills, and mill effluents are provided for 4 streams included in a long-term study to assess potential effects of pulp and paper mill effluents on US receiving waters. The study streams are Codorus Creek (Pennsylvania, USA), Leaf River (Mississippi, USA) and McKenzie and Willamette rivers (Oregon, USA) and were chosen to represent a blend of mill process types, effluent concentrations, and coldwater/warmwater stream systems. The described effluent quality, water quality, and habitat data sets encompass the initial 7 to 8 y of a study anticipated to continue >10 y and provide a backdrop to a series of articles describing periphyton, macroinvertebrate, and fish community properties in these same streams. The mean in-stream waste concentration (IWC) for these 4 effluent discharges was 32.4%, 2.0%, 0.5%, and 0.2% v/v for Codorus Creek and Leaf, McKenzie, and Willamette rivers, respectively, as compared with a median of 0.4% for US mills. Effluent quality measurements included Selenastrum capricornutum, Ceriodaphnia dubia, and Pimephales promelas chronic bioassays as sanctioned by the US Environmental Protection Agency for estimating effluent effects on receiving-water aquatic communities. Based on mean bioassay inhibition concentration for a 25% effect and on mean IWC, a margin of safety against adverse biological effects of 2, 25, 137, and 150 times was indicated for Codorus Creek and Leaf, McKenzie, and Willamette rivers, respectively. Habitat and water quality assessment was carried out over a gradient of sample sites above and below the effluent discharge to determine nonmill-related conditions that might interfere with interpretation of effluent effects. Noneffluent related localized differences in conditions for some parameters, including current velocity (McKenzie River), and surface incident photosynthetically active radiation (Codorus Creek and Willamette River) occurred at the sample stations immediately

  12. LONG-TERM MONITORING SENSOR NETWORK

    Stephen P. Farrington; John W. Haas; Neal Van Wyck

    2003-10-16

    Long-term monitoring (LTM) associated with subsurface contamination sites is a key element of Long Term Stewardship and Legacy Management across the Department of Energy (DOE) complex. However, both within the DOE and elsewhere, LTM is an expensive endeavor, often exceeding the costs of the remediation phase of a clean-up project. The primary contributors to LTM costs are associated with labor. Sample collection, storage, preparation, analysis, and reporting can add a significant financial burden to project expense when extended over many years. Development of unattended, in situ monitoring networks capable of providing quantitative data satisfactory to regulatory concerns has the potential to significantly reduce LTM costs. But survival and dependable operation in a difficult environment is a common obstacle to widespread use across the DOE complex or elsewhere. Deploying almost any sensor in the subsurface for extended periods of time will expose it to chemical and microbial degradation. Over the time-scales required for in situ LTM, even the most advanced sensor systems may be rendered useless. Frequent replacement or servicing (cleaning) of sensors is expensive and labor intensive, offsetting most, if not all, of the cost savings realized with unattended, in situ sensors. To enable facile, remote monitoring of contaminants and other subsurface parameters over prolonged periods, Applied Research Associates, Inc has been working to develop an advanced LTM sensor network consisting of three key elements: (1) an anti-fouling sensor chamber that can accommodate a variety of chemical and physical measurement devices based on electrochemical, optical and other techniques; (2) two rapid, cost effective, and gentle means of emplacing sensor packages either at precise locations directly in the subsurface or in pre-existing monitoring wells; and (3) a web browser-based data acquisition and control system (WebDACS) utilizing field-networked microprocessor-controlled smart

  13. Long-term visual tracking based on correlation filters

    Wei, Quanlu; Lao, Songyang; Bai, Liang

    2017-03-01

    In order to accomplish the long term visual tracking task in complex scenes, solve problems of scale variation, appearance variation and tracking failure, a long term tracking algorithm is given based on the framework of collaborative correlation tracking. Firstly, we integrate several powerful features to boost the represent ability based on the kernel correlation filter, and extend the filter by embedding a scale factor into the kernelized matrix to handle the scale variation. Then, we use the Peak-Sidelobe Ratio to decide whether the object is tracked successfully, and a CUR filter for re-detection the object in case of tracking failure is learnt with random sampling. Corresponding experiment is performed on 17 challenging benchmark video sequences. Compared with the 8 existing state-of-the-art algorithms based on discriminative learning method, the results show that the proposed algorithm improves the tracking performance on several indexes, and is robust to complex scenes for long term visual tracking.

  14. Hormonal changes during long-term isolation.

    Custaud, M A; Belin de Chantemele, E; Larina, I M; Nichiporuk, I A; Grigoriev, A; Duvareille, M; Gharib, C; Gauquelin-Koch, G

    2004-05-01

    Confinement and inactivity induce considerable psychological and physiological modifications through social and sensory deprivation. The aim of the SFINCSS-99 experiment was to determine the cardiovascular and hormonal pattern of blood volume regulation during long-term isolation and confinement. Simulation experiments were performed in pressurized chambers similar in size to the volumes of modern space vehicles. Group I consisted of four Russian male volunteers, who spent 240 days in a 100-m(3 )chamber. Group II included four males (one German and three Russians) who spent 110 days in isolation (200-m(3) module). The blood samples, taken before, during and after the isolation period, were used to determine haematocrit (Ht), growth hormone (GH), active renin, aldosterone, and osmolality levels. From the urine samples, electrolytes, osmolality, nitrites, nitrates, cortisol, antidiuretic hormone (ADH), aldosterone, normetanephrine and metanephrine levels were determined. The increase in plasma volume (PV) that is associated with a tendency for a decrease in plasma active renin is likely to be due to decreased sympathetic activity, and concords with the changes in urinary catecholamine levels during confinement. Urinary catecholamine levels were significantly higher during the recovery period than during confinement. This suggests that the sympathoadrenal system was activated, and concords with the increase in heart rate. Vascular resistance is determined by not only the vasoconstrictor but also vasodilator systems. The ratio of nitrite/nitrate in urine, as an indicator of nitric oxide release, did not reveal any significant changes. Analysis of data suggests that the duration of the isolation was a main factor involved in the regulation of hormones.

  15. Long-term follow-up study and long-term care of childhood cancer survivors

    Hyeon Jin Park

    2010-04-01

    Full Text Available The number of long-term survivors is increasing in the western countries due to remarkable improvements in the treatment of childhood cancer. The long-term complications of childhood cancer survivors in these countries were brought to light by the childhood cancer survivor studies. In Korea, the 5-year survival rate of childhood cancer patients is approaching 70%; therefore, it is extremely important to undertake similar long-term follow-up studies and comprehensive long-term care for our population. On the basis of the experiences of childhood cancer survivorship care of the western countries and the current Korean status of childhood cancer survivors, long-term follow-up study and long-term care systems need to be established in Korea in the near future. This system might contribute to the improvement of the quality of life of childhood cancer survivors through effective intervention strategies.

  16. Long-term Multiwavelength Observations of Polars

    Santana, Joshua; Mason, Paul A.

    2016-06-01

    Polars are cataclysmic variables with the highest magnetic field strengths (10-250 MG). Matter is accreted after being funneled by the strong magnetic field of the white dwarf. We perform a meta-study of multi-wavelength data of polars. Many polars have been observed in surveys, such as SDSS, 2MASS, ROSAT, just to name a few. Some polars have now been detected by the JVLA, part of an expanding class of radio CVs. A large subset of polars have long-term optical light curves from CRTS and AAVSO. We suggest that the long term light curves of polars display a variety of signature behaviors and may be grouped accordingly. Additional characteristics such a binary period, magnetic field strengths, X-ray properties, and distance estimates are examined in context with long-term observations.

  17. Inflammatory markers in relation to long-term air pollution.

    Mostafavi, Nahid; Vlaanderen, Jelle; Chadeau-Hyam, Marc; Beelen, Rob; Modig, Lars; Palli, Domenico; Bergdahl, Ingvar A; Vineis, Paolo; Hoek, Gerard; Kyrtopoulos, Soterios Α; Vermeulen, Roel

    2015-08-01

    Long-term exposure to ambient air pollution can lead to chronic health effects such as cancer, cardiovascular and respiratory disease. Systemic inflammation has been hypothesized as a putative biological mechanism contributing to these adverse health effects. We evaluated the effect of long-term exposure to air pollution on blood markers of systemic inflammation. We measured a panel of 28 inflammatory markers in peripheral blood samples from 587 individuals that were biobanked as part of a prospective study. Participants were from Varese and Turin (Italy) and Umea (Sweden). Long-term air pollution estimates of nitrogen oxides (NOx) were available from the European Study of Cohorts for Air Pollution Effects (ESCAPE). Linear mixed models adjusted for potential confounders were applied to assess the association between NOx and the markers of inflammation. Long-term exposure to NOx was associated with decreased levels of interleukin (IL)-2, IL-8, IL-10 and tumor necrosis factor-α in Italy, but not in Sweden. NOx exposure levels were considerably lower in Sweden than in Italy (Sweden: median (5th, 95th percentiles) 6.65 μg/m(3) (4.8, 19.7); Italy: median (5th, 95th percentiles) 94.2 μg/m(3) (7.8, 124.5)). Combining data from Italy and Sweden we only observed a significant association between long-term exposure to NOx and decreased levels of circulating IL-8. We observed some indication for perturbations in the inflammatory markers due to long-term exposure to NOx. Effects were stronger in Italy than in Sweden, potentially reflecting the difference in air pollution levels between the two cohorts.

  18. Attenuated long-term Arc expression in the aged fascia dentata

    2010-01-01

    One prominent component of aging is a defect in memory stabilization. To understand how the formation of enduring memories is altered in the aged brain, long-term markers of the biological events that may mediate memory consolidation were used to examine the activity dynamics of hippocampal circuits over extended intervals. The immediate-early gene Arc, which is implicated in both durable memory and synaptic plasticity, is expressed in the fascia dentata (FD) for long periods following behavi...

  19. Keratoprosthesis: a long-term review.

    Barnham, J J; Roper-Hall, M J

    1983-07-01

    A keratoprosthesis (KP), is an artificial cornea which is inserted into an opacified cornea in an attempt to restore useful vision or, less commonly, to make the eye comfortable in painful keratopathy. Results o a retrospective study of 35 patients, with 55 KP insertions, are reviewed with regard to visual acuity, length of time vision is maintained, retention time, and complication. Overall there were a number of long-term real successes, eith retention of the KP and maintenance of improved vision in eyes not amenable to conventional treatment. Careful long-term follow-up was needed, with further surgical procedures often being necessary.

  20. [Fetal pain: immediate and long term consequences].

    Houfflin Debarge, Véronique; Dutriez, Isabelle; Pusniak, Benoit; Delarue, Eléonore; Storme, Laurent

    2010-06-01

    Several situations are potentially painful for fetuses, such as malformations and invasive procedures. Nociceptive pathways are known to be functional at 26 weeks. Even if it is not possible to evaluate the fetal experience of pain, it is essential to examine its immediate and long-term consequences. As early as the beginning of the second trimester, hemodynamic and hormonal responses are observed following fetal nociceptive stimulation, In experimental studies, long-term changes have been noted in the corticotrop axis, subsequent responses to pain, and behavior after perinatal nociceptive stimulation.