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Sample records for samples long-term memory

  1. Andra long term memory project - 59277

    Document available in abstract form only. Full text of publication follows: Long term memory of repositories is required by safety, reversibility and social expectations. Thus Andra has implemented since 2010 a long-term memory project to reinforce and diversify its current arrangements in this field, as well as to explore opportunities to extend memory keeping over thousands years. The project includes opportunity studies of dedicated facilities. The 'Ecotheque' and 'Geotheque' projects contribute to memory respectively through environmental and geological samples preservation. The options of creating (i) an archive centre for Andra's interim and permanent archives, (ii) an artist center to study the contribution of arts to memory preservation, (iii) a museum of radioactive waste disposal history and technology (radium industry..., sea disposal, current solutions...) are considered. Other studies provided by the project examine our heritage. This includes the continuity of languages and symbolic systems, the continuity of writing and engraving methods, the archaeology of landscapes (memory of the earths evolution, multi-century memory of industrial and agricultural landscapes), the archaeology practices (how might a future archaeologist be interested in our current activity?), the preservation of historical sites and industrial memory, the continuity of institutional organizations, the memory and history of science evolution as well as broad history

  2. A cost of long-term memory in Drosophila

    Mery, Frederic; Kawecki, Tadeusz J

    2005-01-01

    Two distinct forms of consolidated associative memory are known in Drosophila: long-term memory and so-called anesthesia-resistant memory. Long-term memory is more stable, but unlike anesthesia-resistant memory, its formation requires protein synthesis. We show that flies induced to form long-term memory become more susceptible to extreme stress (such as desiccation). In contrast, induction of anesthesia-resistant memory had no detectable effect on desiccation resistance. This finding may hel...

  3. Long Term Immunological Memory to Vaccinia Virus

    Halla Halldórsdóttir 1987

    2012-01-01

    The smallpox vaccine is a vaccine of considerable importance. It made the eradication of smallpox possible and has been shown to elicit humoral and cellular immunity that can last for over half a century. Due to concerns about smallpox being used as a biological weapon, the immune response to the vaccine is of considerable interest. In this study, long term B- and T-cell responses were investigated in individuals with extreme responses to the smallpox vaccine when they were immunised over thr...

  4. Children's Long-Term Memory for Autobiographical Events.

    Peterson, Carole

    2002-01-01

    Traces the origins of children's autobiographical memories, discussing research on infantile amnesia and young children's memory skills. Focuses on studies of children's long-term memory for autobiographical events that investigate delays of 1-2 years and delays of 4 years or more. Reports that a few studies have documented remarkably robust…

  5. Long-term memory impairment in patients with focal epilepsy.

    Hoppe, Christian; Elger, Christian E; Helmstaedter, Christoph

    2007-01-01

    In temporal lobe epilepsy, long-term memory disturbance starts early in life mainly affecting declarative memory. Primary impairment of episodic memory often results in reduced semantic and autobiographic memory. Neuropsychological performance predicts academic achievement and everyday life functioning while subjective memory complaints are highly correlated with depression. Memory impairment is also influenced by initial brain damage, developmental retardation and dynamic factors (e.g., seizure frequency, medication). Damage of functional tissue, low mental reserve capacity, and poor seizure outcome increase the risk for postsurgical memory impairment whereas functional release due to seizure freedom counteracts negative impact. Preliminary findings indicate that postsurgical training improves memory deficits and encourage further research. PMID:18047597

  6. Consolidation of Long-Term Memory: Evidence and Alternatives

    Meeter, Martijn; Murre, Jaap M. J.

    2004-01-01

    Memory loss in retrograde amnesia has long been held to be larger for recent periods than for remote periods, a pattern usually referred to as the Ribot gradient. One explanation for this gradient is consolidation of long-term memories. Several computational models of such a process have shown how consolidation can explain characteristics of…

  7. Long-term memory of individual identity in ant queens

    Dreier, Stéphanie Agnès Jeanine; Van Zweden, Jelle Stijn; D'Ettorre, Patrizia

    2007-01-01

    of familiar or unfamiliar queens over time. We show that unrelated founding queens of P. villosa and Pachycondyla inversa store information on the individual identity of other queens and can retrieve it from memory after 24h of separation. Thus, we have documented for the first time that long......-term memory of individual identity is present and functional in ants. This novel finding represents an advance in our understanding of the mechanism determining the evolution of cooperation among unrelated individuals....

  8. 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

    2013-01-01

    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 eviden...

  9. Merging of long-term memories in an insect.

    Hunt, Kathryn L; Chittka, Lars

    2015-03-16

    Research on comparative cognition has largely focused on successes and failures of animals to solve certain cognitive tasks, but in humans, memory errors can be more complex than simple failures to retrieve information [1, 2]. The existence of various types of "false memories," in which individuals remember events that they have never actually encountered, are now well established in humans [3, 4]. We hypothesize that such systematic memory errors may be widespread in animals whose natural lifestyle involves the processing and recollection of memories for multiple stimuli [5]. We predict that memory traces for various stimuli may "merge," such that features acquired in distinct bouts of training are combined in an animal's mind, so that stimuli that have never been viewed before, but are a combination of the features presented in training, may be chosen during recall. We tested this using bumblebees, Bombus terrestris. When individuals were first trained to a solid single-colored stimulus followed by a black and white (b/w)-patterned stimulus, a subsequent preference for the last entrained stimulus was found in both short-term- and long-term-memory tests. However, when bees were first trained to b/w-patterned stimuli followed by solid single-colored stimuli and were tested in long-term-memory tests 1 or 3 days later, they only initially preferred the most recently rewarded stimulus, and then switched their preference to stimuli that combined features from the previous color and pattern stimuli. The observed merging of long-term memories is thus similar to the memory conjunction error found in humans [6]. PMID:25728692

  10. 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.

  11. Long-term memory in electricity prices: Czech market evidence

    Krištoufek, Ladislav; Luňáčková, P.

    2013-01-01

    Roč. 63, č. 5 (2013), s. 407-424. ISSN 0015-1920 R&D Projects: GA ČR GA402/09/0965 Grant ostatní: GA ČR(CZ) GAP402/11/0948 Institutional support: RVO:67985556 Keywords : electricity * long-term memory Subject RIV: AH - Economics Impact factor: 0.358, year: 2013 http://library.utia.cas.cz/separaty/2014/E/kristoufek-0427660.pdf

  12. 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.

  13. Long-term memory and extremes in historical temperature reconstructions

    Ludescher, J.; Bunde, A.

    2012-12-01

    We analyze the long-term memory in temperature reconstructions for Central Europe which are based on tree-ring widths [1] and chronological records [2] and compare the results with multiproxy temperature reconstructions of the extra tropical region of the Northern Hemisphere [3], instrumental data for Central Europe of the last century and recent millennium simulations (last version, as of 2012, of the MPI-ESM-P model based on ECHAM6). We use the standard methods for detecting long-term memory, (i) detrended fluctuation analysis (DFA2) and (ii) wavelet techniques (WT2), and analyze also (iii) conditional averages and (iv) the distribution of the persistence lengths. In addition, we study (v) the distribution of the return intervals for various return periods. Our results provide coherent evidence that all temperature reconstructions cannot be described by an AR1 process, but are long-term correlated. For both the tree ring based and multi proxy reconstructions, the Hurst exponent H is close to 1, while for the instrumental and model data as well as for the reconstruction based on chronological records H is between 0.6 and 0.7. The inconsistency between the different reconstructions and the output of the millennium runs is severe and raises concern on the usefulness of tree-ring widths to reconstruct the temperature of the past.

  14. 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.

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

    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 to 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

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

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

    2012-01-01

    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 (f0), a vocal measure of encoded emotional arousal, was measured during pre-treatme...

  17. Long-term memory of heterospecific vocalizations by African lions

    Grinnell, Jon; van Dyk, Gus; Slotow, Rob

    2005-09-01

    Animals that use and evaluate long-distance signals have the potential to glean valuable information about others in their environment via eavesdropping. In those areas where they coexist, African lions (Panthera leo) are a significant eavesdropper on spotted hyenas (Crocuta crocuta), often using hyena vocalizations to locate and scavenge from hyena kills. This relationship was used to test African lions' long-term memory of the vocalizations of spotted hyenas via playback experiments. Hyena whoops and a control sound (Canis lupus howls) were played to three populations of lions in South Africa: (1) lions with past experience of spotted hyenas; (2) lions with current experience; and (3) lions with no experience. The results strongly suggest that lions have the cognitive ability to remember the vocalizations of spotted hyenas even after 10 years with no contact of any kind with them. Such long-term memory of heterospecific vocalizations may be widespread in species that gain fitness benefits from eavesdropping on others, but where such species are sympatric and often interact it may pass unrecognized as short-term memory instead.

  18. 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

    2013-01-01

    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 conceptualization of OGM are discussed. PMID:23439226

  19. Modified climate with long term memory in tree ring proxies

    Zhang, Huan; Yuan, Naiming; Esper, Jan; Werner, Johannes P.; Xoplaki, Elena; Büntgen, Ulf; Treydte, Kerstin; Luterbacher, Jürg

    2015-08-01

    Long term memory (LTM) scaling behavior in worldwide tree-ring proxies and subsequent climate reconstructions is analyzed for and compared with the memory structure inherent to instrumental temperature and precipitation data. Detrended fluctuation analysis is employed to detect LTM, and its scaling exponent α is used to evaluate LTM. The results show that temperature and precipitation reconstructions based on ring width measurements (mean α =0.8) contain more memory than records based on maximum latewood density (mean α =0.7). Both exceed the memory inherent to regional instrumental data (α =0.6 for temperature, α =0.5 for precipitation) in the time scales ranging from 1 year up to 50 years. We compare memory-free (α =0.5) pseudo-instrumental precipitation data with pseudo-reconstructed precipitation data with LTM (α \\gt 0.5), and demonstrate the biasing influences of LTM on climate reconstructions. We call for attention to statistical analysis with regard to the variability of proxy-based chronologies or reconstructions, particularly with respect to the contained (i) trends, (ii) past warm/cold period and wet/dry periods; and (iii) extreme events.

  20. 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. PMID:23439226

  1. 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…

  2. Massive Memory Revisited: Limitations on Storage Capacity for Object Details in Visual Long-Term Memory

    Cunningham, Corbin A.; Yassa, Michael A.; Egeth, Howard E.

    2015-01-01

    Previous work suggests that visual long-term memory (VLTM) is highly detailed and has a massive capacity. However, memory performance is subject to the effects of the type of testing procedure used. The current study examines detail memory performance by probing the same memories within the same subjects, but using divergent probing methods. The…

  3. 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…

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

    VIANNA MÔNICA R.M.; IZQUIERDO LUCIANA A.; BARROS DANIELA M.; WALZ ROGER; MEDINA JORGE H.; IZQUIERDO IVÁN

    2000-01-01

    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 th...

  5. Fragile Associations Coexist with Robust Memories for Precise Details in Long-Term Memory

    Lew, Timothy F.; Pashler, Harold E.; Vul, Edward

    2016-01-01

    What happens to memories as we forget? They might gradually lose fidelity, lose their associations (and thus be retrieved in response to the incorrect cues), or be completely lost. Typical long-term memory studies assess memory as a binary outcome (correct/incorrect), and cannot distinguish these different kinds of forgetting. Here we assess…

  6. Long-term memory of individual identity in ant queens.

    Dreier, Stephanie; van Zweden, Jelle S; D'Ettorre, Patrizia

    2007-10-22

    Remembering individual identities is part of our own everyday social life. Surprisingly, this ability has recently been shown in two social insects. While paper wasps recognize each other individually through their facial markings, the ant, Pachycondyla villosa, uses chemical cues. In both species, individual recognition is adaptive since it facilitates the maintenance of stable dominance hierarchies among individuals, and thus reduces the cost of conflict within these small societies. Here, we investigated individual recognition in Pachycondyla ants by quantifying the level of aggression between pairs of familiar or unfamiliar queens over time. We show that unrelated founding queens of P. villosa and Pachycondyla inversa store information on the individual identity of other queens and can retrieve it from memory after 24h of separation. Thus, we have documented for the first time that long-term memory of individual identity is present and functional in ants. This novel finding represents an advance in our understanding of the mechanism determining the evolution of cooperation among unrelated individuals. PMID:17594958

  7. 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. PMID:26323831

  8. 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.

  9. Exploring the interaction between working memory and long-term memory: Evidence for the workspace model

    van der Meulen, Marian

    2008-01-01

    There is a large range of models of working memory, each with different scopes and emphases. Current interest focuses strongly on the interaction of working memory with long-term memory, as it has become clear that models of working memory alone are incapable of capturing some of our complex cognitive abilities. Most models have contrasting views on how this interaction is implemented. In this thesis, three classes of models are defined, each proposing a different type of interaction. The fir...

  10. 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 in patients with MTL lesions on tasks with short retention intervals, or no retention interval, and neuroimaging findings with similar tasks have be...

  11. 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. PMID:22542535

  12. Visual Long-Term Memory Has the Same Limit on Fidelity as Visual Working Memory

    Alvarez, George Angelo; Brady, Timothy Francis; Konkle, Talia A; Gill, Jonathan; Oliva, Aude

    2013-01-01

    Visual long-term memory can store thousands of objects with surprising visual detail, but just how detailed are these representations, and how can one quantify this fidelity? Using the property of color as a case study, we estimated the precision of visual information in long-term memory, and compared this with the precision of the same information in working memory. Observers were shown real-world objects in random colors and were asked to recall the colors after a delay. We quantified two p...

  13. Creating the Unforgettable: The Short Story of Mapping Long-Term Memory

    Wang, Samantha X.Y.

    2011-01-01

    Memory is a binary process relying on a short-term form lasting minutes to forge and communicate with a long-term form lasting years. Yale’s Bicentennial Symposium opened with a lecture elucidating the obscure process of long-term memory formation. From his decades of research, Nobel Laureate Eric Kandel offered insight into the molecular framework that is long term-memory.

  14. Creating the unforgettable: the short story of mapping long-term memory. Bicentennial Symposium.

    Wang, Samantha X Y

    2011-06-01

    Memory is a binary process relying on a short-term form lasting minutes to forge and communicate with a long-term form lasting years. Yale's Bicentennial Symposium opened with a lecture elucidating the obscure process of long-term memory formation. From his decades of research, Nobel Laureate Eric Kandel offered insight into the molecular framework that is long term-memory. PMID:21698048

  15. Analysis of long term samples in Tore Supra

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

    1995-04-01

    Long term samples have been installed on the inner wall in Tore Supra to monitor the surface modification of the graphite tiles. Surface analyses have shown a very low metallic impurity concentration (˜ 10 16 at/cm 2) dominated by stainless steel compounds. The high deuterium concentration (> 10 18 at/cm 2) is due to a codeposition with carbon atoms. Carbon layers of about 1 μm have been measured from which we deduced a carbon recycling coefficient RC = 0.99.

  16. Analysis of long term samples in Tore Supra

    Gauthier, E. [Association Euratom-CEA sur la Fusion Controlee, Centre d`Etudes de Cadarache, Saint-Paul-lez-Durance (France); Grosman, A. [Association Euratom-CEA sur la Fusion Controlee, Centre d`Etudes de Cadarache, Saint-Paul-lez-Durance (France); Valter, J. [Association Euratom-CEA sur la Fusion Controlee, Centre d`Etudes de Cadarache, Saint-Paul-lez-Durance (France)

    1995-04-01

    Long term samples have been installed on the inner wall in Tore Supra to monitor the surface modification of the graphite tiles. Surface analyses have shown a very low metallic impurity concentration ( similar 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. ((orig.)).

  17. 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.

  18. 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.

  19. Interacting Memory Systems—Does EEG Alpha Activity Respond to Semantic Long-Term Memory Access in a Working Memory Task?

    Barbara Berger; Serif Omer; Tamas Minarik; Annette Sterr; Paul Sauseng

    2014-01-01

    Memory consists of various individual processes which form a dynamic system co-ordinated by central (executive) functions. The episodic buffer as direct interface between episodic long-term memory (LTM) and working memory (WM) is fairly well studied but such direct interaction is less clear in semantic LTM. Here, we designed a verbal delayed-match-to-sample task specifically to differentiate between pure information maintenance and mental manipulation of memory traces with and without involv...

  20. Memory Functioning in Children with Reading Disabilities and/or Attention-Deficit/Hyperactivity Disorder: A Clinical Investigation of Their Working Memory and Long-term Memory Functioning

    Kibby, Michelle Y.; Morris J. Cohen

    2008-01-01

    We examined memory functioning in children with reading disabilities (RD), ADHD, and RD/ADHD using a clinic sample with a clinical instrument: the Children’s Memory Scale, enhancing its generalizability. Participants included 23 children with RD, 30 with ADHD, 30 with RD/ADHD, and 30 controls. Children with RD presented with reduced verbal short-term memory (STM) but intact visual STM, central executive (CE) and long-term memory (LTM) functioning. Their deficit in STM appeared specific to tas...

  1. They Saw a Movie: Long-Term Memory for an Extended Audiovisual Narrative

    Furman, Orit; Dorfman, Nimrod; Hasson, Uri; Davachi, Lila; Dudai, Yadin

    2007-01-01

    We measured long-term memory for a narrative film. During the study session, participants watched a 27-min movie episode, without instructions to remember it. During the test session, administered at a delay ranging from 3 h to 9 mo after the study session, long-term memory for the movie was probed using a computerized questionnaire that assessed…

  2. Media multitasking and memory: Differences in working memory and long-term memory.

    Uncapher, Melina R; K Thieu, Monica; Wagner, Anthony D

    2016-04-01

    Increasing access to media in the 21st century has led to a rapid rise in the prevalence of media multitasking (simultaneous use of multiple media streams). Such behavior is associated with various cognitive differences, such as difficulty filtering distracting information and increased trait impulsivity. Given the rise in media multitasking by children, adolescents, and adults, a full understanding of the cognitive profile of media multitaskers is imperative. Here we investigated the relationship between chronic media multitasking and working memory (WM) and long-term memory (LTM) performance. Four key findings are reported (1) heavy media multitaskers (HMMs) exhibited lower WM performance, regardless of whether external distraction was present or absent; (2) lower performance on multiple WM tasks predicted lower LTM performance; (3) media multitasking-related differences in memory reflected differences in discriminability rather than decision bias; and (4) attentional impulsivity correlated with media multitasking behavior and reduced WM performance. These findings suggest that chronic media multitasking is associated with a wider attentional scope/higher attentional impulsivity, which may allow goal-irrelevant information to compete with goal-relevant information. As a consequence, heavy media multitaskers are able to hold fewer or less precise goal-relevant representations in WM. HMMs' wider attentional scope, combined with their diminished WM performance, propagates forward to yield lower LTM performance. As such, chronic media multitasking is associated with a reduced ability to draw on the past-be it very recent or more remote-to inform present behavior. PMID:26223469

  3. Long-term memory stabilized by noise-induced rehearsal.

    Wei, Yi; Koulakov, Alexei A

    2014-11-19

    Cortical networks can maintain memories for decades despite the short lifetime of synaptic strengths. Can a neural network store long-lasting memories in unstable synapses? Here, we study the effects of ongoing spike-timing-dependent plasticity (STDP) on the stability of memory patterns stored in synapses of an attractor neural network. We show that certain classes of STDP rules can stabilize all stored memory patterns despite a short lifetime of synapses. In our model, unstructured neural noise, after passing through the recurrent network connections, carries the imprint of all memory patterns in temporal correlations. STDP, combined with these correlations, leads to reinforcement of all stored patterns, even those that are never explicitly visited. Our findings may provide the functional reason for irregular spiking displayed by cortical neurons and justify models of system memory consolidation. Therefore, we propose that irregular neural activity is the feature that helps cortical networks maintain stable connections. PMID:25411507

  4. Merging of Long-Term Memories in an Insect

    Kathryn Louise Hunt

    2012-01-01

    The way in which we process sensory input and our ability to store it in memory and subsequently recall it to enable modification of our behaviour appropriate to the current situation, has long been of interest. The degree to which memories for multiple inputs within the same sensory domain affect the recall of one another has been widely studied in humans, with interference theory and the use of the misinformation effect to produce false memories now widely accepted. However aside from some ...

  5. Intrahippocampal Wortmannin Infusion Enhances Long-Term Spatial and Contextual Memories

    Dash, Pramod K; Mach, Sara A.; Blum, Sonja; Moore, Anthony N.

    2002-01-01

    The transition from short- to long-term memory involves several biochemical cascades, some of which act in an antagonistic manner. Post-training intrahippocampal administration of wortmannin, a pharmacological inhibitor of phosphatidylinositol 3-kinase, had no effect on memory tested 3 h later, but improved long-term memory tested 48 h following the completion of training. This effect was seen in two hippocampus-dependent tasks: the Morris water maze, using both massed and distributed trainin...

  6. 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

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

    Micol Tomaiuolo

    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.

  8. 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...

  9. Anomalous Fluctuations in Autoregressive Models with Long-Term Memory

    Sakaguchi, Hidetsugu

    2015-01-01

    An autoregressive model with a power-law type memory kernel is studied as a stochastic process that exhibits a self-affine-fractal-like behavior for a small time scale. We find numerically that the root-mean-square displacement for the time interval increases with a power law for small time but saturates at sufficiently large time. The exponent changes with the power exponent of the memory kernel.

  10. 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.

  11. Merging of Long-Term Memories in an Insect

    Kathryn Louise Hunt

    2012-04-01

    Full Text Available The way in which we process sensory input and our ability to store it in memory and subsequently recall it to enable modification of our behaviour appropriate to the current situation, has long been of interest. The degree to which memories for multiple inputs within the same sensory domain affect the recall of one another has been widely studied in humans, with interference theory and the use of the misinformation effect to produce false memories now widely accepted. However aside from some evidence for the effect of interference on memory, it is still largely unknown to what extent memories for multiple stimuli may affect recall of one another and in what way this may occur in non-human animals. We hypothesise that the memory traces for multiple stimuli may ‘merge’, such that features acquired in distinct bouts of training are combined in an animals mind, so that stimuli that have actually never been viewed before, but are a combination of the features presented in training may be chosen during memory recall. We tested this using the bumblebee Bombus terrestris as a model due to its excellent memory for colours and patterns, such as those of flowers and their capacity to learn multiple stimuli. A reversal learning paradigm was used to train bees to a b/w- patterned stimulus followed by a solid single-colour stimulus. Bees were then tested at one of three time intervals post-learning using both of the original stimuli and a ‘merged’ stimulus, combining elements of both the training stimuli without being identical to either one. Twenty-four hours after training, bees initially selected the last rewarded stimulus and the ’merged’ stimulus with the highest frequency. Our analysis showed that over the course of the test, preference switched from initially being for the last rewarded stimulus, to the ‘merged’ stimulus. This was the result of a genuine confusion or ‘merging’ of the information from the memory traces of both training stimuli and not just due to a generalisation to the training colour. When a different, non-relevant pattern was used in training but the same ‘merged’ stimulus was displayed in the test, bees selected only the last rewarded stimulus: colour with the highest frequency, with no stimulus switching over the course of the test. This is the first example of memory ’merging’ in a non-human animal.

  12. 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…

  13. 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…

  14. Recollection-based memory in frontotemporal dementia: implications for theories of long-term memory.

    Simons, Jon S; Verfaellie, Mieke; Galton, Clare J; Miller, Bruce L; Hodges, John R; Graham, Kim S

    2002-11-01

    It has been convincingly demonstrated that patients with semantic dementia (the temporal variant of frontotemporal dementia) can show intact recognition memory for pictorial stimuli. As yet, the contribution made by recollective processes to this ability and the status of associated neural regions have not been investigated in the disease. Here, we used both a source monitoring paradigm and an associative memory test to evaluate the ability of patients with semantic dementia to use recollection-based memory processes, and a volumetric MRI technique to assess the extent of atrophy in the hippocampus. Although some patients showed impaired source and associative memory, many performed as well as control participants. Importantly, status of semantic knowledge, as measured by tests of comprehension and production, did not predict recollection-based memory ability. There was no significant positive correlation between recollection and volume of the hippocampus; instead, both source discrimination and associative memory correlated highly with performance on a battery of frontal lobe tests. Consistent with the view that damage to the prefrontal cortex might influence recollection performance, patients with the frontal variant of frontotemporal dementia, with atrophy largely confined to the frontal lobes, all performed at floor level on source discrimination. These results provide further compelling evidence in favour of the multiple input model of long-term memory and highlight the role of frontal lobe systems in recollection-based memory. PMID:12390977

  15. Cognitive control during selective long-term-memory retrieval

    Kizilirmak, Jasmin

    2013-01-01

    In every waking moment of our life, we are focusing our conscious processing of information on certain perceptions, ideas, feelings, and memories. In other words, we are filtering information, or selectively attending to specific occurrences in our environment (external perceptions) and to thoughts (internal perceptions) all the time. For example, imagine you want to bake a marble cake: How much flour, butter, and sugar do you nee...

  16. 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…

  17. 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…

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

    Colomb, J.; Kaiser, Laetitia; Chabaud, M.-A.; Preat, T.

    2009-01-01

    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...

  19. 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…

  20. 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…

  1. 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

    2010-01-01

    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 has focused either on short- (or “working memory”) or on long-term memory. Using an auditory–verbal continuous recognition paradigm designed for fMRI,...

  2. 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…

  3. 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…

  4. 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…

  5. A Survey of Current Literature on Sampling, Sample Handling, and Long Term Storage for Environmental Materials.

    Maienthal, E. J.; Becker, D. A.

    This report presents the results of an extensive literature survey undertaken to establish optimum sampling, sample handling and long-term storage techniques for a wide variety of environmental samples to retain sample integrity. The components of interest are trace elements, organics, pesticides, radionuclides and microbiologicals. A bibliography…

  6. What are the differences between long-term, short-term, and working memory?

    Cowan, Nelson

    2008-01-01

    In the recent literature there has been considerable confusion about the three types of memory: long-term, short-term, and working memory. This chapter strives to reduce that confusion and makes up-to-date assessments of these types of memory. Long- and short-term memory could differ in two fundamental ways, with only short-term memory demonstrating (1) temporal decay and (2) chunk capacity limits. Both properties of short-term memory are still controversial but the current literature is rath...

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

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

    2016-02-01

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

  8. 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. PMID:26821291

  9. Modality-specific alpha modulations facilitate long-term memory encoding in the presence of distracters.

    Jiang, Haiteng; van Gerven, Marcel A J; Jensen, Ole

    2015-03-01

    It has been proposed that long-term memory encoding is not only dependent on engaging task-relevant regions but also on disengaging task-irrelevant regions. In particular, oscillatory alpha activity has been shown to be involved in shaping the functional architecture of the working brain because it reflects the functional disengagement of specific regions in attention and memory tasks. We here ask if such allocation of resources by alpha oscillations generalizes to long-term memory encoding in a cross-modal setting in which we acquired the ongoing brain activity using magnetoencephalography. Participants were asked to encode pictures while ignoring simultaneously presented words and vice versa. We quantified the brain activity during rehearsal reflecting subsequent memory in the different attention conditions. The key finding was that successful long-term memory encoding is reflected by alpha power decreases in the sensory region of the to-be-attended modality and increases in the sensory region of the to-be-ignored modality to suppress distraction during rehearsal period. Our results corroborate related findings from attention studies by demonstrating that alpha activity is also important for the allocation of resources during long-term memory encoding in the presence of distracters. PMID:25244116

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

    Amnon Yacoby

    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 effects of neonatal single or multiple isoflurane exposures on spatial memory in rats

    MarkGBaxter

    2013-07-01

    Full Text Available General anesthetics are neurotoxic to neonatal rodents and nonhuman primates. Neonatal exposure to general anesthetics has been associated with long-term cognitive deficits in animal models. Some data from humans are consistent with long-term deleterious effects of anesthetic exposure early in life on cognitive development, with multiple exposures to general anesthetics being particularly damaging. We sought to determine whether repeated exposure of neonatal rats to anesthesia was associated with long-term cognitive impairments and whether the magnitude of impairments was greater than that resulting from a single exposure. Male or female Long-Evans rat pups were exposed to 1.8% isoflurane for 2 hours on postnatal day (P 7, or for 2 hours each on P7, P10, and P13. Testing in a spatial working memory task began on P91. Rats that were repeatedly exposed to isoflurane were impaired relative to controls in the spatial working memory task. Male rats that received a single exposure to isoflurane showed an unexpected facilitation in spatial memory performance. These results support the hypothesis that multiple neonatal exposures to general anesthesia are associated with greater long-term cognitive impairment than a single exposure. The findings are congruent with human epidemiological studies reporting long-term cognitive impairments following multiple but not single general anesthetics early in life.

  12. SNAP-25 in hippocampal CA3 region is required for long-term memory formation

    SNAP-25 is a synaptosomal protein of 25 kDa, a key component of synaptic vesicle-docking/fusion machinery, and plays a critical role in exocytosis and neurotransmitter release. We previously reported that SNAP-25 in the hippocampal CA1 region is involved in consolidation of contextual fear memory and water-maze spatial memory (Hou et al. European J Neuroscience, 20: 1593-1603, 2004). SNAP-25 is expressed not only in the CA1 region, but also in the CA3 region, and the SNAP-25 mRNA level in the CA3 region is higher than in the CA1 region. Here, we provide evidence that SNAP-25 in the CA3 region is also involved in learning/memory. Intra-CA3 infusion of SNAP-25 antisense oligonucleotide impaired both long-term contextual fear memory and water-maze spatial memory, with short-term memory intact. Furthermore, the SNAP-25 antisense oligonucleotide suppressed the long-term potentiation (LTP) of field excitatory post-synaptic potential (fEPSP) in the mossy-fiber pathway (DG-CA3 pathway), with no effect on paired-pulse facilitation of the fEPSP. These results are consistent with the notion that SNAP-25 in the hippocampal CA3 region is required for long-term memory formation

  13. 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 by different stimulation paradigms.

  14. Long-term working memory: A computational implementation for chess expertise

    Gobet, F.

    2000-01-01

    Long-term working memory (Ericsson and Kintsch, 1995) is a theory covering empirical data from several domains, including expert behaviour. One difficulty in applying and evaluating this theory, however, is that it is framed in rather general terms, and that several mechanisms and parameters are left unspecified. This paper proposes a computer implementation of the theory for a domain that Ericsson and Kintsch cover in depth, namely chess memory. Simulations of Saariluoma’s (1989) experiment ...

  15. Late protein synthesis-dependent phases in CTA long-term memory: BDNF requirement

    Martha L Escobar

    2011-09-01

    Full Text Available It has been proposed that long-term memory 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 long-term memory 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 hours 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.

  16. Guidance of Attention to Objects and Locations by Long-Term Memory of Natural Scenes

    Becker, Mark W.; Rasmussen, Ian P.

    2008-01-01

    Four flicker change-detection experiments demonstrate that scene-specific long-term memory guides attention to both behaviorally relevant locations and objects within a familiar scene. Participants performed an initial block of change-detection trials, detecting the addition of an object to a natural scene. After a 30-min delay, participants…

  17. 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). PMID:23376769

  18. Behavioral Specifications of Reward-Associated Long-Term Memory Enhancement in Humans

    Wittmann, Bianca C.; Dolan, Raymond J.; Duzel, Emrah

    2011-01-01

    Recent functional imaging studies link reward-related activation of the midbrain substantia nigra-ventral tegmental area (SN/VTA), the site of origin of ascending dopaminergic projections, with improved long-term episodic memory. Here, we investigated in two behavioral experiments how (1) the contingency between item properties and reward, (2) the…

  19. Protein Phosphatase 1-Dependent Transcriptional Programs for Long-Term Memory and Plasticity

    Graff, Johannes; Koshibu, Kyoko; Jouvenceau, Anne; Dutar, Patrick; Mansuy, Isabelle M.

    2010-01-01

    Gene transcription is essential for the establishment and the maintenance of long-term memory (LTM) and for long-lasting forms of synaptic plasticity. The molecular mechanisms that control gene transcription in neuronal cells are complex and recruit multiple signaling pathways in the cytoplasm and the nucleus. Protein kinases (PKs) and…

  20. 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…

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

    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. Intrahippocampal Glutamine Administration Inhibits mTORC1 Signaling and Impairs Long-Term Memory

    Rozas, Natalia S.; Redell, John B.; Pita-Almenar, Juan D.; McKenna, James, III.; Moore, Anthony N.; Gambello, Michael J.; Dash, Pramod K.

    2015-01-01

    The mechanistic Target of Rapamycin Complex 1 (mTORC1), a key regulator of protein synthesis and cellular growth, is also required for long-term memory formation. Stimulation of mTORC1 signaling is known to be dependent on the availability of energy and growth factors, as well as the presence of amino acids. In vitro studies using serum- and amino…

  3. Behavioral Specifications of Reward-Associated Long-Term Memory Enhancement in Humans

    Wittmann, Bianca C.; Dolan, Raymond J.; Duzel, Emrah

    2011-01-01

    Recent functional imaging studies link reward-related activation of the midbrain substantia nigra-ventral tegmental area (SN/VTA), the site of origin of ascending dopaminergic projections, with improved long-term episodic memory. Here, we investigated in two behavioral experiments how (1) the contingency between item properties and reward, (2) the…

  4. Transgenic Mice Expressing an Inhibitory Truncated Form of p300 Exhibit Long-Term Memory Deficits

    Oliveira, Ana M. M.; Wood, Marcelo A.; McDonough, Conor B.; Abel, Ted

    2007-01-01

    The formation of many forms of long-term memory requires several molecular mechanisms including regulation of gene expression. The mechanisms directing transcription require not only activation of individual transcription factors but also recruitment of transcriptional coactivators. CBP and p300 are transcriptional coactivators that interact with…

  5. HDAC inhibition modulates hippocampus-dependent long-term memory for object location in a CBP-dependent manner

    Haettig, Jakob; Stefanko, Daniel P.; Multani, Monica L.; Figueroa, Dario X.; McQuown, Susan C.; Wood, Marcelo A.

    2011-01-01

    Transcription of genes required for long-term memory not only involves transcription factors, but also enzymatic protein complexes that modify chromatin structure. Chromatin-modifying enzymes, such as the histone acetyltransferase (HAT) CREB (cyclic-AMP response element binding) binding protein (CBP), are pivotal for the transcriptional regulation required for long-term memory. Several studies have shown that CBP and histone acetylation are necessary for hippocampus-dependent long-term memory...

  6. 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. PMID:26754811

  7. Measuring Adult Memory: The Development and Validation of a New Instrument To Measure Long-term Memory in Adults.

    Schenck, Jeb

    2001-01-01

    An instrument measuring visual memory span in long-term memory was tested on 239 adults using pictures of common objects. Correlations were found between the number of images recalled and age, level of education, level of income, intelligence, sex, and social activity. (Contains 21 references.) (Author/JOW)

  8. Erosion of long-term wall samples in JET

    The erosion of carbon and the deposition of carbon and impurities have been determined for graphite samples exposed at the wall of JET during the six months of operation in 1985. Graphite erosion was determined using SIMS analysis of the depth change of implanted 13C marker layers in the samples. Impurity deposition was measured using SIMS and Rutherford backscattering. The samples showed high erosion ranging from 0.2 to 0.6 ?m at various locations, with significant poloidal variation in both erosion and deposition. The deposition of substantial quantities of metal impurities and carbon was related to a probe accident and a deliberate heavy carbonization procedure during the operation period. The highest observed erosion exceeds the expected sputter erosion due to charge exchange neutrals by more than an order of magnitude, unless neutral fluxes are enhanced at the inner wall due to ions arriving along open field lines during current ramp-down. (orig.)

  9. Deuterium-depleted water has stimulating effects on long-term memory in rats.

    Mladin, Cristian; Ciobica, Alin; Lefter, Radu; Popescu, Alexandru; Bild, Walther

    2014-11-01

    Deuterium-depleted water (DDW) is a water which has a 6-7-fold less concentration of the naturally occurring deuterium (20-25ppm vs. 150ppm). While administrated for a longer period, it may reduce the concentration of deuterium throughout the body, thus activating cellular mechanisms which are depending on protons (channels, pumps, enzyme proteins). The aim of the present work was to study, for the first time in our knowledge, the possible influence of deuterium-depleted water (DDW) chronic administration in normal Wistar rats, as compared to a control group which received distilled water, on spatial working memory and the locomotor activity (as studied through Y-maze) or both short-term and long-term spatial memory (assed in radial 8 arms-maze task). Our results presented here showed no significant modifications in terms of spatial working memory (assessed through spontaneous alternation percentage) and locomotor activity (expressed through the number of arm entries) in Y-maze, as a result of DDW ingestion. Also, no significant differences between the DDW and control group were found in terms of the number of working memory errors in the eight-arm radial maze, as a parameter of short-term memory. Still, we observed a significant decrease for the number of reference memory errors in the DDW rats. In this way, we could speculate that the administration of DDW may generate an improvement of the reference memory, as an index of long-term memory. Thus, we can reach the conclusion that the change between the deuterium/hydrogen balance may have important consequences for the mechanisms that govern long-term memory, as showed here especially in the behavioral parameters from the eight-arm radial maze task. PMID:25263786

  10. Rapamycin-sensitive signalling in long-term consolidation of auditory cortex-dependent memory.

    Tischmeyer, Wolfgang; Schicknick, Horst; Kraus, Michaela; Seidenbecher, Constanze I; Staak, Sabine; Scheich, Henning; Gundelfinger, Eckart D

    2003-08-01

    New memories initially persist in a labile state and require protein synthesis-dependent processes of consolidation for long-term manifestation. Using differential conditioning to linearly frequency-modulated tones (FMs) we have recently shown that post-training injections of protein synthesis inhibitors into the auditory cortex of Mongolian gerbils interfere with long-term memory for a number of days. Here, we have used rapamycin as a pharmacological tool to elucidate signalling pathways that control the synthesis of proteins required for persistent memory storage. In mammalian cells, inhibition of target of rapamycin (TOR)-mediated pathways was shown to block the translation of distinct classes of mRNAs. Bilateral infusions of rapamycin into the gerbil auditory cortex shortly after FM discrimination training did not impair the maintenance of the newly acquired memory trace for 24 h, but caused profound retention deficits at 48 h after injection. Control experiments showed that the amnesic action is rapamycin-dependent, confined to the context of memory formation, and suppressed by the antagonist FK506. These data indicate that, in the mammalian brain, activation of rapamycin-sensitive signalling pathways contributes to long-term consolidation of a cerebral cortex-dependent form of memory. Moreover, the finding that rapamycin-induced amnesia parallels only late effects of conventional protein synthesis inhibitors on FM discrimination memory implies that at least two different protein synthesis-dependent processes control memory formation. Both are activated during or shortly after learning. Whereas one process is required for the initial maintenance of memory for about one day the second one is involved in the regulation of its long-lasting persistence in conditioning to FMs. PMID:12925020

  11. Acute pentobarbital treatment impairs spatial learning and memory and hippocampal long-term potentiation in rats.

    Wang, Wei; Tan, Tao; Tu, Man; He, Wenting; Dong, Zhifang; Han, Huili

    2015-10-01

    Reports of the effects of pentobarbital on learning and memory are contradictory. Some studies have not shown any interference with learning and memory, whereas others have shown that pentobarbital impairs memory and that these impairments can last for long periods. However, it is unclear whether acute local microinjections of pentobarbital affect learning and memory, and if so, the potential mechanisms are also unclear. Here, we reported that the intra-hippocampal infusion of pentobarbital (8.0mM, 1?l per side) significantly impaired hippocampus-dependent spatial learning and memory retrieval. Moreover, in vitro electrophysiological recordings revealed that these behavioral changes were accompanied by impaired hippocampal CA1 long-term potentiation (LTP) and suppressed neuronal excitability as reflected by a decrease in the number of action potentials (APs). These results suggest that acute pentobarbital application causes spatial learning and memory deficits that might be attributable to the suppression of synaptic plasticity and neuronal excitability. PMID:26056078

  12. Effects of long term childhood mild swimming on the adulthood learning and memory in the rat

    Siamak Shahidi

    2008-12-01

    Full Text Available Introduction: The positive effects of exercise on many physiological systems, including the central nervous system, are well-established. Exercise decrease the age related impairment of learning and memory. There is no clear report concerning the effects of childhood exercise on the cognitive function during adulthood. The aim of present study was to investigate the effects of long term mild swimming exercise during childhood on the inhibitory avoidance and spatial learning and memory in the adulthood rats. Methods: Four weeks old male Wistar rats were divided randomly into the swimmer and sedentary (control groups. The swimming procedure was continued for 6 weeks. One week after the end of swimming period, inhibitory avoidance learning and memory of rats were tested. Two weeks later, spatial learning and memory test of rats were begun by using radial maze. The training procedure was done during 15 days. Then, 6 days later, spatial memory test was assessed. Results: The results of inhibitory avoidance test showed that the number of trials to acquisition in the control rats was significantly more than swimmer rats group. The results of retention test revealed that there were no significant differences in the STL and TDC between swimmer and control groups. In the radial maze task, two experimental groups showed the same learning ability in the finding the baited food arms on the 15th days. The results of retrieval test indicated that the number of total memory errors, reference memory errors and working memory errors in the swimmer group of rat were significantly less than the non-swimmer group of rat. Conclusion: It can be concluded that long term mild exercise in the childhood period can improve the acquisition but it had no significant effects on the retrieval of inhibitory avoidance learning and memory task during the adulthood. Also, long term swimming improves the long term and short term memory in the complex maze task even after cessation of swimming. This result may due to the effects of swimming on the synaptic activity in the neural structure which are involve in the learning and memory processing.

  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. 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. PMID:21419628

  15. 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.

  16. Delayed Dopamine Signaling of Energy Level Builds Appetitive Long-Term Memory in Drosophila

    Pierre-Yves Musso

    2015-02-01

    Full Text Available Sensory cues relevant to a food source, such as odors, can be associated with post-ingestion signals related either to food energetic value or toxicity. Despite numerous behavioral studies, a global understanding of the mechanisms underlying these long delay associations remains out of reach. Here, we demonstrate in Drosophila that the long-term association between an odor and a nutritious sugar depends on delayed post-ingestion signaling of energy level. We show at the neural circuit level that the activity of two pairs of dopaminergic neurons is necessary and sufficient to signal energy level to the olfactory memory center. Accordingly, we have identified in these dopaminergic neurons a delayed calcium trace that correlates with appetitive long-term memory formation. Altogether, these findings demonstrate that the Drosophila brain remembers food quality through a two-step mechanism that consists of the integration of olfactory and gustatory sensory information and then post-ingestion energetic value.

  17. Do as I … Did! Long-term memory of imitative actions in dogs (Canis familiaris).

    Fugazza, Claudia; Pogány, Ákos; Miklósi, Ádám

    2016-03-01

    This study demonstrates long-term declarative memory of imitative actions in a non-human animal species. We tested 12 pet dogs for their ability to imitate human actions after retention intervals ranging from 1 to 24 h. For comparison, another 12 dogs were tested for the same actions without delay between demonstration and recall. Our test consisted of a modified version of the Do as I Do paradigm, combined with the two-action procedure to control for non-imitative processes. Imitative performance of dogs remained consistently high independent of increasing retention intervals, supporting the idea that dogs are able to retain mental representations of human actions for an extended period of time. The ability to imitate after such delays supports the use of long-term declarative memory. PMID:26498155

  18. 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 and long-term memory encoding/recall) instead of applying isolated tasks to map temporoparietal regions, (b) analyzing NE data based on performances recorded during REC, (c) double-mapping networks involved in naming and in long-term memory encoding and retrieval, (d) focusing on remembering with hippocampal activation and familiarity judgment with lateral temporal cortices activation, and (e) short duration of examination and feasibility. These aspects are of particular interest in patients with TLE, who frequently show impairment of these cognitive functions. Here, we show that the novel protocol is suited for this clinical evaluation. PMID:26575255

  19. 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. PMID:26869978

  20. Operant Conditioning in Lymnaea: Evidence for Intermediate- and Long-term Memory

    Lukowiak, Ken; Adatia, Nimet; Krygier, Darin; Syed, Naweed

    2000-01-01

    Aerial respiration of the pond snail, Lymnaea stagnalis, can be operantly conditioned; however, the parameters necessary to produce long-term (LTM) or intermediate term memory (ITM) have not previously been investigated. We conducted training using procedures that varied in the duration of the training session, the number of training sessions per day or the amount of time between subsequent training sessions (SI). We found that by varying the duration and frequency of the training session lea...

  1. 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. PMID:26869978

  2. 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 ...

  3. 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...

  4. 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

  5. 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

  6. A requirement for the immediate early gene Zif268 in the expression of late LTP and long-term memories.

    Jones, M W; Errington, M L; French, P J; Fine, A; Bliss, T V; Garel, S; Charnay, P; Bozon, B; Laroche, S; Davis, S

    2001-03-01

    The induction of long-term potentiation (LTP) in the dentate gyrus of the hippocampus is associated with a rapid and robust transcription of the immediate early gene Zif268. We used a mutant mouse with a targeted disruption of Zif268 to ask whether this gene, which encodes a zinc finger transcription factor, is required for the maintenance of late LTP and for the expression of long-term memory. We show that whereas mutant mice exhibit early LTP in the dentate gyrus, late LTP is absent when measured 24 and 48 hours after tetanus in the freely moving animal. In both spatial and non-spatial learning tasks, short-term memory remained intact, whereas performance was impaired in tests requiring long-term memory. Thus, Zif268 is essential for the transition from short- to long-term synaptic plasticity and for the expression of long-term memories. PMID:11224546

  7. Verapamil enhances the impairing effects of stress on retrieval of long-term memory in rats

    A. Rashidy-Pour

    2006-11-01

    Full Text Available Introduction: This study investigated an interaction between acute restraint stress and verapamil, as a blocker of L-type voltage sensitive channels on retrieval of long-term memory. Materials and Methods: Young adult male rats were trained in one trial inhibitory avoidance task (1mA, 1.5s footshock. On retention test given 48 hr after training, the latency to re-enter dark compartment and time spent in light chamber of the apparatus were recorded. Thirty min before retention test, the rats were exposed to a 10 min of restraint stress in a Plexiglass with or without prior treatment of verapamil (5, 10, 20 mg/kg. Results: The results showed verapamil pretreatment enhanced the impairing effect of stress on memory retrieval. The applied stress increased circulating corticosterone levels as assessed immediately after the retention test, indicating that stress–induced impairment of memory retrieval is mediated, in part, by increased plasma levels of glucocorticoids. Verapamil did not affect on this response. Conclusion: These findings indicate that acute restraint stress impair retrieval of long-term memory, and provide evidence for the existence of an interaction between stress and L-type voltage calcium channels on this process.

  8. Long-term memory in speech perception: Some new findings on talker variability, speaking rate and perceptual learning *

    Pisoni, David B.

    1993-01-01

    This paper summarizes results from recent studies on the role of long-term memory in speech perception and spoken word recognition. Experiments on talker variability, speaking rate and perceptual learning provide strong evidence for implicit memory for very fine perceptual details of speech. Listeners apparently encode specific attributes of the talker’s voice and speaking rate into long-term memory. Acoustic–phonetic variability does not appear to be “lost” as a result of phonetic analysis. ...

  9. 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.

  10. Sleep Improves Memory: The Effect of Sleep on Long Term Memory in Early Adolescence

    Potkin, Katya Trudeau; Bunney, William E

    2012-01-01

    Sleep plays an important role in the consolidation of memory. This has been most clearly shown in adults for procedural memory (i.e. skills and procedures) and declarative memory (e.g. recall of facts). The effects of sleep and memory are relatively unstudied in adolescents. Declarative memory is important in school performance and consequent social functioning in adolescents. This is the first study to specifically examine the effects of normal sleep on auditory declarative memory in an earl...

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

    Veronique Ginsburg

    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.

  12. Dopaminergic neurotransmission dysfunction induced by amyloid-β transforms cortical long-term potentiation into long-term depression and produces memory impairment.

    Moreno-Castilla, Perla; Rodriguez-Duran, Luis F; Guzman-Ramos, Kioko; Barcenas-Femat, Alejandro; Escobar, Martha L; Bermudez-Rattoni, Federico

    2016-05-01

    Alzheimer's disease (AD) is a neurodegenerative condition manifested by synaptic dysfunction and memory loss, but the mechanisms underlying synaptic failure are not entirely understood. Although dopamine is a key modulator of synaptic plasticity, dopaminergic neurotransmission dysfunction in AD has mostly been associated to noncognitive symptoms. Thus, we aimed to study the relationship between dopaminergic neurotransmission and synaptic plasticity in AD models. We used a transgenic model of AD (triple-transgenic mouse model of AD) and the administration of exogenous amyloid-β (Aβ) oligomers into wild type mice. We found that Aβ decreased cortical dopamine levels and converted in vivo long-term potentiation (LTP) into long-term depression (LTD) after high-frequency stimulation delivered at basolateral amygdaloid nucleus-insular cortex projection, which led to impaired recognition memory. Remarkably, increasing cortical dopamine and norepinephrine levels rescued both high-frequency stimulation -induced LTP and memory, whereas depletion of catecholaminergic levels mimicked the Aβ-induced shift from LTP to LTD. Our results suggest that Aβ-induced dopamine depletion is a core mechanism underlying the early synaptopathy and memory alterations observed in AD models and acts by modifying the threshold for the induction of cortical LTP and/or LTD. PMID:27103531

  13. Binding neutral information to emotional contexts: Brain dynamics of long-term recognition memory.

    Ventura-Bort, Carlos; Löw, Andreas; Wendt, Julia; Moltó, Javier; Poy, Rosario; Dolcos, Florin; Hamm, Alfons O; Weymar, Mathias

    2016-04-01

    There is abundant evidence in memory research that emotional stimuli are better remembered than neutral stimuli. However, effects of an emotionally charged context on memory for associated neutral elements is also important, particularly in trauma and stress-related disorders, where strong memories are often activated by neutral cues due to their emotional associations. In the present study, we used event-related potentials (ERPs) to investigate long-term recognition memory (1-week delay) for neutral objects that had been paired with emotionally arousing or neutral scenes during encoding. Context effects were clearly evident in the ERPs: An early frontal ERP old/new difference (300-500 ms) was enhanced for objects encoded in unpleasant compared to pleasant and neutral contexts; and a late central-parietal old/new difference (400-700 ms) was observed for objects paired with both pleasant and unpleasant contexts but not for items paired with neutral backgrounds. Interestingly, objects encoded in emotional contexts (and novel objects) also prompted an enhanced frontal early (180-220 ms) positivity compared to objects paired with neutral scenes indicating early perceptual significance. The present data suggest that emotional-particularly unpleasant-backgrounds strengthen memory for items encountered within these contexts and engage automatic and explicit recognition processes. These results could help in understanding binding mechanisms involved in the activation of trauma-related memories by neutral cues. PMID:26530244

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

    Krištoufek, Ladislav; Vošvrda, Miloslav

    Jihlava : College of Polytechnics Jihlava, 2013 - (Vojáčková, H.), s. 470-475 ISBN 978-80-87035-76-4. [International Conference on Mathematical Methods in Economics 2013 /31./. Jihlava (CZ), 11.09.2013-13.09.2013] R&D Projects: GA ČR GA402/09/0965 Grant ostatní: MŠk(CZ) SVV265504 Institutional support: RVO:67985556 Keywords : capital market efficiency * long-range dependence * fractal dimension * approximate entropy Subject RIV: AH - Economics http://library.utia.cas.cz/separaty/2013/E/kristoufek-measuring capital market efficienci long-term memory fractal dimension and approximate entropy.pdf

  15. Measuring capital market efficiency: long-term memory, fractal dimension and approximate entropy

    Kristoufek, Ladislav; Vosvrda, Miloslav

    2014-07-01

    We utilize long-term memory, fractal dimension and approximate entropy as input variables for the Efficiency Index [L. Kristoufek, M. Vosvrda, Physica A 392, 184 (2013)]. 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 America (Venezuela and Chile).

  16. 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…

  17. 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…

  18. Roles of NO signaling in long-term memory formation in visual learning in an insect.

    Matsumoto, Yukihisa; Hirashima, Daisuke; Terao, Kanta; Mizunami, Makoto

    2013-01-01

    Many insects exhibit excellent capability of visual learning, but the molecular and neural mechanisms are poorly understood. This is in contrast to accumulation of information on molecular and neural mechanisms of olfactory learning in insects. In olfactory learning in insects, it has been shown that cyclic AMP (cAMP) signaling critically participates in the formation of protein synthesis-dependent long-term memory (LTM) and, in some insects, nitric oxide (NO)-cyclic GMP (cGMP) signaling also plays roles in LTM formation. In this study, we examined the possible contribution of NO-cGMP signaling and cAMP signaling to LTM formation in visual pattern learning in crickets. Crickets that had been subjected to 8-trial conditioning to associate a visual pattern with water reward exhibited memory retention 1 day after conditioning, whereas those subjected to 4-trial conditioning exhibited 30-min memory retention but not 1-day retention. Injection of cycloheximide, a protein synthesis inhibitor, into the hemolymph prior to 8-trial conditioning blocked formation of 1-day memory, whereas it had no effect on 30-min memory formation, indicating that 1-day memory can be characterized as protein synthesis-dependent long-term memory (LTM). Injection of an inhibitor of the enzyme producing an NO or cAMP prior to 8-trial visual conditioning blocked LTM formation, whereas it had no effect on 30-min memory formation. Moreover, injection of an NO donor, cGMP analogue or cAMP analogue prior to 4-trial conditioning induced LTM. Induction of LTM by an NO donor was blocked by DDA, an inhibitor of adenylyl cyclase, an enzyme producing cAMP, but LTM induction by a cAMP analogue was not impaired by L-NAME, an inhibitor of NO synthase. The results indicate that cAMP signaling is downstream of NO signaling for visual LTM formation. We conclude that visual learning and olfactory learning share common biochemical cascades for LTM formation. PMID:23894314

  19. 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.

  20. 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...

  1. 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.

    2011-01-01

    In humans, training in which good performance is rewarded or bad performance punished results in transient behavioral improvements [1–3]. Their relative effects on consolidation and long-term retention, critical behavioral stages for successful learning [4, 5], 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 con...

  2. 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.

  3. 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.

  4. 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.

  5. Providing misleading and reinstatement information a year after it happened: effects on long-term memory.

    Peterson, Carole; Parsons, Tina; Dean, Myra

    2004-01-01

    The question addressed here is whether misleading suggestions made to children a year after target events had occurred will alter long-term recall. One group (3-13 years old when injured and treated in a hospital Emergency Room) were given both misleading and accurate reinstating information a year later, and recall of target events assessed both 1 week and another year later (i.e., 2 years post-injury). A control group had recall assessed both 1 and 2 years post-injury. Misleading had little effect on children's recall 1 week later, although a few misled details were reported. However, a year later virtually none of the misleading information was incorporated into long-term recall. Rather, children were more, not less, accurate when recalling details about which they had been misled. Results were attributed to target events having been highly memorable and well rehearsed via previous recalls, and detection of discrepancies between memory and misleading information focusing attention on targeted details. PMID:15098617

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

    Chen, Ling, E-mail: 2006chenling2006@163.com [College of Computer Science, Chongqing University, Chongqing 400044 (China); Li, Chuandong, E-mail: licd@cqu.edu.cn [College of Computer Science, Chongqing University, Chongqing 400044 (China); Huang, Tingwen [Texas A and M University at Qatar, Doha, B.O. Box 23874 (Qatar); Ahmad, Hafiz Gulfam [College of Computer Science, Chongqing University, Chongqing 400044 (China); Chen, Yiran [Electrical and Computer Engineering, University of Pittsburgh, PA 15261 (United States)

    2014-08-14

    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. - Highlights: • We take the Fick diffusion and the Soret diffusion into account in the ion drift theory. • We develop a new model based on the old HP model. • The new model can describe the forgetting effect and the spike-rate-dependent property of memristor. • The new model can solve the boundary effect of all window functions discussed in [13]. • A new Hopfield neural network with the forgetting ability is built by the new memristor model.

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

    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. - Highlights: • We take the Fick diffusion and the Soret diffusion into account in the ion drift theory. • We develop a new model based on the old HP model. • The new model can describe the forgetting effect and the spike-rate-dependent property of memristor. • The new model can solve the boundary effect of all window functions discussed in [13]. • A new Hopfield neural network with the forgetting ability is built by the new memristor model

  8. 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 conclusion, these brain transcriptomes provide candidate genes that may be involved in the observed natural variation in LTM in closely related Cotesia parasitic wasp species.

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

    van Vugt, Joke J F A; Hoedjes, Katja M; van de Geest, Henri C; Schijlen, Elio W G M; Vet, Louise E M; Smid, Hans M

    2015-01-01

    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 (US) in a classical conditioning paradigm, where plant odors become associated with 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 conclusion, these brain transcriptomes provide candidate genes that may be involved in the observed natural variation in LTM in closely related Cotesia parasitic wasp species. PMID:26557061

  10. 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. PMID:26835842

  11. Short-term and long-term memory in early temporal lobe dysfunction.

    Hershey, T; Craft, S; Glauser, T A; Hale, S

    1998-01-01

    Following medial temporal damage, mature humans are impaired in retaining new information over long delays but not short delays. The question of whether a similar dissociation occurs in children was addressed by testing children (ages 7-16) with unilateral temporal lobe epilepsy (TLE) and controls on short- and long-term memory tasks, including a spatial delayed response task (SDR). Early-onset TLE did not affect performance on short delays on SDR, but it did impair performance at the longest delay (60 s), similar to adults with unilateral medial temporal damage. In addition, early-onset TLE affected performance on pattern recall, spatial span, and verbal span with rehearsal interference. No differences were found on story recall or on a response inhibition task. PMID:9460735

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

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

    2014-01-01

    Ca(2+)/calmodulin (CaM)-dependent protein kinase II (CaMKII) is a key molecule in many systems of learning and memory in vertebrates, but roles of CaMKII in invertebrates have not been characterized in detail. We have suggested that serial activation of NO/cGMP signaling, cyclic nucleotide-gated channel, Ca(2+)/CaM and cAMP signaling participates in long-term memory (LTM) formation in olfactory conditioning in crickets, and here we show participation of CaMKII in LTM formation and propose its site of action in the biochemical cascades. Crickets subjected to 3-trial conditioning to associate an odor with reward exhibited memory that lasts for a few days, which is characterized as protein synthesis-dependent LTM. In contrast, animals subjected to 1-trial conditioning exhibited memory that lasts for only several hours (mid-term memory, MTM). Injection of a CaMKII inhibitor prior to 3-trial conditioning impaired 1-day memory retention but not 1-hour memory retention, suggesting that CaMKII participates in LTM formation but not in MTM formation. Animals injected with a cGMP analogue, calcium ionophore or cAMP analogue prior to 1-trial conditioning exhibited 1-day retention, and co-injection of a CaMKII inhibitor impaired induction of LTM by the cGMP analogue or that by the calcium ionophore but not that by the cAMP analogue, suggesting that CaMKII is downstream of cGMP production and Ca(2+) influx and upstream of cAMP production in biochemical cascades for LTM formation. Animals injected with an adenylyl cyclase (AC) activator prior to 1-trial conditioning exhibited 1-day retention. Interestingly, a CaMKII inhibitor impaired LTM induction by the AC activator, although AC is expected to be a downstream target of CaMKII. The results suggest that CaMKII interacts with AC to facilitate cAMP production for LTM formation. We propose that CaMKII serves as a key molecule for interplay between Ca(2+) signaling and cAMP signaling for LTM formation, a new role of CaMKII in learning and memory. PMID:25215889

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

    Li, Yong; Kim, Jimok

    2016-01-01

    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. PMID:26819779

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

    Li, Yong; Kim, Jimok

    2016-01-01

    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. PMID:26819779

  16. A Diffusion Model Analysis of Adult Age Differences in Episodic and Semantic Long-Term Memory Retrieval

    Spaniol, Julia; Madden, David J.; Voss, Andreas

    2006-01-01

    Two experiments investigated adult age differences in episodic and semantic long-term memory tasks, as a test of the hypothesis of specific age-related decline in context memory. Older adults were slower and exhibited lower episodic accuracy than younger adults. Fits of the diffusion model (R. Ratcliff, 1978) revealed age-related increases in…

  17. A role for high frequency hydrochemical sampling in long term ecosystem studies

    Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Kendall, C.

    2007-12-01

    Monitoring of surface waters for major chemical constituents is needed to assess long-term trends and responses to ecological disturbance. However, the typical fixed-interval (weekly, monthly, or quarterly) sampling schemes of most long-term ecosystem studies may not capture the full range of stream chemical variation and do not always provide enough information to discern the landscape processes that control surface water chemistry and solute loadings. To expand upon traditional hydrochemical monitoring, we collected high frequency event-based surface water samples at an upland, forested basin of the Sleepers River Research Watershed (Vermont, USA), one of five intensively studied sites in the Water, Energy, and Biogeochemical Budgets (WEBB) program of the US Geological Survey. We present several examples that highlight the importance of linking long-term weekly data with intensive, high frequency sampling. We used end-member mixing analysis and isotopic approaches to trace sources of stream nutrients (e.g. nitrate, dissolved organic carbon) and quantified how atmospheric pollutants (e.g. nitrogen, sulfate, and mercury) affect stream chemistry. High frequency sampling generates large numbers of samples and is both labor and resource intensive but yields insights into ecosystem functions that are not readily discerned from less-frequent sampling. As the ecological community contemplates the scope and foci of environmental observatories as benchmarks for deciphering the effects of natural and anthropogenic change, incorporating high frequency hydrochemical sampling will further our understanding of ecosystem functions across a range of ecosystem types and disturbance effects.

  18. Four-hour delayed memory recall for stories: Theoretical and clinical implications of measuring accelerated long-term forgetting.

    Ladowsky-Brooks, Ricki L

    2016-01-01

    It has been noted that clinical neuropsychological assessment is "blind" to certain abnormalities of consolidation that occur beyond standard 30-min delay intervals. For example, normal forgetting at 30-min delays has been followed by enhanced forgetting at longer delays in temporal-lobe epilepsy, termed accelerated long-term forgetting (ALF). To evaluate whether ALF could be identified in the neuropsychological assessment of a small sample of examinees with head injuries or other neurological diagnoses (n = 42), a 4-hr delayed recall condition was added to the Logical Memory subtest of the Wechsler Memory Scale-Third Edition. A small percentage of examinees (5/42 or 11%), despite exhibiting unimpaired story recall immediately and after 30-min delays, showed increased forgetting when compared with the average retention of stories (M = 0.83, SD = 0.17) after a 4-hr delay. Three of these 5 examinees also had impaired scores on 20-min delayed recall of the California Verbal Learning Test-Second Edition (CVLT-II) and would have been identified as having memory impairment without an extended, 4-hr delayed recall. In fact, the highest correlation among memory indexes was between 4-hr delayed recall of stories and delayed recall of the CVLT-II word list (r = .59, p < .0001), suggesting different consolidation rates for relational and nonrelational material. PMID:26502999

  19. Stress and glucocorticoid receptor-dependent mechanisms in long-term memory: from adaptive responses to psychopathologies

    Finsterwald, Charles; Cristina M Alberini

    2013-01-01

    A proper response against stressors is critical for survival. In mammals, the stress response is primarily mediated by secretion of glucocorticoids via the hypothalamic-pituitaryadrenocortical (HPA) axis and release of catecholamines through adrenergic neurotransmission. Activation of these pathways results in a quick physical response to the stress and, in adaptive conditions, mediates long-term changes in the brain that lead to the formation of long-term memories of the experience. These lo...

  20. Word-frequency effects in long-term semantic priming and false memory.

    Sherman, Susan M; Jordan, Timothy R

    2011-08-01

    Several studies have used the lexical decision task (LDT) with the Deese-Roediger-McDermott (DRM) false-memory paradigm to investigate whether long-term semantic priming (LTSP) occurs following presentation of lists of items (e.g., bed, dream, snore) for related non-presented lure words (e.g., sleep). However, results have been mixed, with some studies observing priming, whilst others have not. The present study had four goals: (i) to investigate the existence of LTSP in the LDT; (ii) to investigate effects of LTSP on standard effects of word frequency on LDT performance; (iii) to investigate the effect, if any, of word frequency on true and false recall; and (iv) to compare LDT performance with performance on a subsequent free-recall task. The findings showed (i) a significant effect of LTSP on LDT performance; (ii) no effect of LTSP on standard effects of word frequency on LDT performance; (iii) no effect of word frequency on either true or false free recall; and (iv) a significant relationship between LDT and free-recall performance. Implications of these findings for understanding LTSP and false memories are discussed. PMID:21752006

  1. Semantic congruency but not temporal synchrony enhances long-term memory performance for audio-visual scenes.

    Meyerhoff, Hauke S; Huff, Markus

    2016-04-01

    Human long-term memory for visual objects and scenes is tremendous. Here, we test how auditory information contributes to long-term memory performance for realistic scenes. In a total of six experiments, we manipulated the presentation modality (auditory, visual, audio-visual) as well as semantic congruency and temporal synchrony between auditory and visual information of brief filmic clips. Our results show that audio-visual clips generally elicit more accurate memory performance than unimodal clips. This advantage even increases with congruent visual and auditory information. However, violations of audio-visual synchrony hardly have any influence on memory performance. Memory performance remained intact even with a sequential presentation of auditory and visual information, but finally declined when the matching tracks of one scene were presented separately with intervening tracks during learning. With respect to memory performance, our results therefore show that audio-visual integration is sensitive to semantic congruency but remarkably robust against asymmetries between different modalities. PMID:26620810

  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...... 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....

  3. 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

    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...

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

    Wittmann, B. C.; Tan, G. C.; Lisman, J. E.; Dolan, R J; Düzel, E.

    2013-01-01

    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...

  5. A Role for the Insular Cortex in Long-Term Memory for Context-Evoked Drug Craving in Rats

    Contreras, Marco; Billeke, Pablo; Vicencio, Sergio; Madrid, Carlos; Perdomo, Guetón; González, Marcela; Torrealba, Fernando

    2012-01-01

    Drug craving critically depends on the function of the interoceptive insular cortex, and may be triggered by contextual cues. However, the role of the insula in the long-term memory linking context with drug craving remains unknown. Such a memory trace probably resides in some neocortical region, much like other declarative memories. Studies in humans and rats suggest that the insula may include such a region. Rats chronically implanted with bilateral injection cannulae into the high-order ro...

  6. Test of a motor theory of long-term auditory memory.

    Schulze, Katrin; Vargha-Khadem, Faraneh; Mishkin, Mortimer

    2012-05-01

    Monkeys can easily form lasting central representations of visual and tactile stimuli, yet they seem unable to do the same with sounds. Humans, by contrast, are highly proficient in auditory long-term memory (LTM). These mnemonic differences within and between species raise the question of whether the human ability is supported in some way by speech and language, e.g., through subvocal reproduction of speech sounds and by covert verbal labeling of environmental stimuli. If so, the explanation could be that storing rapidly fluctuating acoustic signals requires assistance from the motor system, which is uniquely organized to chain-link rapid sequences. To test this hypothesis, we compared the ability of normal participants to recognize lists of stimuli that can be easily reproduced, labeled, or both (pseudowords, nonverbal sounds, and words, respectively) versus their ability to recognize a list of stimuli that can be reproduced or labeled only with great difficulty (reversed words, i.e., words played backward). Recognition scores after 5-min delays filled with articulatory-suppression tasks were relatively high (75-80% correct) for all sound types except reversed words; the latter yielded scores that were not far above chance (58% correct), even though these stimuli were discriminated nearly perfectly when presented as reversed-word pairs at short intrapair intervals. The combined results provide preliminary support for the hypothesis that participation of the oromotor system may be essential for laying down the memory of speech sounds and, indeed, that speech and auditory memory may be so critically dependent on each other that they had to coevolve. PMID:22511719

  7. 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.

  8. Chronic stress exacerbates impairment of spatial long-term memory in LPA1-null mice

    Luis Javier-Santin

    2009-06-01

    Full Text Available Lysophosphatidic acid (LPA has emerged as a new regulatory molecule in the brain. Recently, some studies have demonstrated a role for this molecule and its LPA1 receptor in the regulation of plasticity and neurogenesis in the adult brain. However, no systematic studies have been conducted to investigate whether the LPA1 receptor is involved in behavior. We studied the effects of the absence of lysophosphatidic acid receptor LPA1, alone or in combination with chronic stress (immobilization in plexiglass tubes for 21 days (3 h/day using male LPA1 receptor knockout (KO and wild type (WT mice. We hypothesized that chronic stress affects diferently the hippocampal function in both genotypes. In order to study this hypothesis the mice were trained in a hole board test to assess both spatial long-term (LTM and working memory (WM. Our data indicate that the absence of LPA1 receptor impairs spatial LTM. In addition, KO mice showed an impairment in the WM task only during the first and second training days, likely associated with the acquisition of the WM rule. Hippocampal BDNF mRNA levels were increased in both WT and KO mice, but WT mice showed greater enhancement than KO mice. After immobilization WT mice showed an impairment mainly in the LTM task. Interestingly, the strongest spatial LTM impairment was observed when KO mice were training in the hole board after immobilization. In addition, immobilization did not potentiate the spatial WM deficits previously observed in KO mice. Our results suggest that LPA1 receptors play an important role in the formation of spatial LTM. In addition, the interaction between the absence of LPA1 receptor and chronic stress impairs the hippocampal-dependent memory. This work was supported by SEJ2007-61187, FIS exp.07/0629, CTS433, CTS065 and AP-2006-02582.

  9. 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…

  10. Zif268/Egr1 gain of function facilitates hippocampal synaptic plasticity and long-term spatial recognition memory

    Penke, Zsuzsa; Morice, Elise; Veyrac, Alexandra; Gros, Alexandra; Chagneau, Carine; LeBlanc, Pascale; Samson, Nathalie; Baumgärtel, Karsten; Mansuy, Isabelle M.; Davis, Sabrina; Laroche, Serge

    2014-01-01

    It is well established that Zif268/Egr1, a member of the Egr family of transcription factors, is critical for the consolidation of several forms of memory; however, it is as yet uncertain whether increasing expression of Zif268 in neurons can facilitate memory formation. Here, we used an inducible transgenic mouse model to specifically induce Zif268 overexpression in forebrain neurons and examined the effect on recognition memory and hippocampal synaptic transmission and plasticity. We found that Zif268 overexpression during the establishment of memory for objects did not change the ability to form a long-term memory of objects, but enhanced the capacity to form a long-term memory of the spatial location of objects. This enhancement was paralleled by increased long-term potentiation in the dentate gyrus of the hippocampus and by increased activity-dependent expression of Zif268 and selected Zif268 target genes. These results provide novel evidence that transcriptional mechanisms engaging Zif268 contribute to determining the strength of newly encoded memories. PMID:24298160

  11. Aluminium chloride impairs long-term memory and downregulates cAMP-PKA-CREB signalling in rats

    Epidemiological investigations have indicated that aluminium (Al) is an important environmental neurotoxicant that may be involved in the aetiology of the cognitive dysfunction associated with neurodegenerative diseases. Additionally, exposure to Al is known to cause neurobehavioural abnormalities in animals. Previous studies demonstrated that Al impaired early-phase long-term potentiation (E-LTP) in vivo and in vitro. Our previous research revealed that Al could impair long-term memory via the impairment of late-phase long-term potentiation (L-LTP) in vivo. However, the exact mechanism by which Al impairs long-term memory has been poorly studied thus far. This study was designed not only to observe the effects of subchronic Al treatment on long-term memory and hippocampal ultrastructure but also to explore a possible underlying mechanism (involving the cAMP-PKA-CREB signalling pathway) in the hippocampus of rats.. Pregnant Wistar rats were assigned to four groups. Neonatal rats were exposed to Al by parental lactation for 3 weeks and then fed with distilled water containing 0, 0.2%, 0.4% or 0.6% Al chloride (AlCl3) for 3 postnatal months. The levels of Al in the blood and hippocampus were quantified by atomic absorption spectrophotometry. The shuttle–box test was performed to detect long-term memory. The hippocampus was collected for ultrastructure observation, and the level of cAMP-PKA-CREB signalling was examined. The results showed that the Al concentrations in the blood and hippocampus of Al-treated rats were higher than those of the control rats. Al may impair the long-term memory of rats. Hippocampal cAMP, cPKA, pCREB, BDNF and c-jun expression decreased significantly, and the neuronal and synaptic ultrastructure exhibited pathological changes after Al treatment. These results indicated that Al may induce long-term memory damage in rats by inhibiting cAMP-PKA-CREB signalling and altering the synaptic and neuronal ultrastructure in the hippocampus

  12. The effect of intrahippocampal microinjection of Naloxone on short –term and long-term memory in adult male rats

    Hoda Parsa

    2012-07-01

    Full Text Available Introduction:The hippocampus is one for the major centers of learning and memory. Role of the opioid system has been investigated and on the other hand receptors related to this system such as mu-opioid receptors (MOR are extended in the hippocampus. In this study the effect of Naloxone administration as a mu opioid receptor antagonist on passive avoidance memory in adult male rats was investigated by using shuttle box instrument. Methods:Methods: In this study 45 male adult Wistar rats at range of 200± 20 were used. They were cannulated after anesthesia and Naloxone 0.5, 1, 1.5 and 2 µg/rat has been injected intrahippocampally after recovery and post training by shuttle box .Then after 90 minute short –term memory and after 24 hours long- term memory were measured posttrainingly. Results:results showed that naloxone0.5, 1, 1.5 and 2µg/rat didn’t affected short – term memory on the other hand according to results of long-term memory showed that Naloxone 0.5 µg/rat didn’t affected memory and Naloxone 1 and 1.5 µg/rat improved memory and Naloxone 2 µg/rat impaired memory. Conclusion:Considering to obtained results it seems that Naloxone affected learning and memory in a dose dependent manner.

  13. A Diffusion Model Analysis of Adult Age Differences in Episodic and Semantic Long-Term Memory Retrieval

    Spaniol, Julia; Madden, David J.; Voss, Andreas

    2006-01-01

    Two experiments investigated adult age differences in episodic and semantic long-term memory tasks, as a test of the hypothesis of specific age-related decline in context memory. Older adults were slower and exhibited lower episodic accuracy than younger adults. Fits of the diffusion model (R. Ratcliff, 1978) revealed age-related increases in nondecisional reaction time for both episodic and semantic retrieval. In Experiment 2, an age difference in boundary separation also indicated an age-re...

  14. The GABAB receptor antagonist CGP 36,742 and the nootropic oxiracetam facilitate the formation of long-term memory.

    Mondadori, C; Möbius, H J; Borkowski, J

    1996-05-01

    The memory-enhancing effects of a single treatment with the GABAB antagonist CGP 36,742 (10 mg/kg) or the nootropic agent oxiracetam (100 mg/kg) given immediately after a learning experience ('post-trial') remain detectable for at least 4 months thereafter. This indicates that in all probability these substances facilitate the formation of the long-term memory trace. PMID:8762175

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

    Krištoufek, Ladislav

    2015-01-01

    Roč. 421, č. 1 (2015), s. 218-222. ISSN 0378-4371 R&D Projects: GA ČR(CZ) GP14-11402P Institutional support: RVO:67985556 Keywords : Power-law cross-correlations * Long term memory * Short term memory Subject RIV: AH - Economics Impact factor: 1.732, year: 2014 http://library.utia.cas.cz/separaty/2015/E/kristoufek-0452316.pdf

  16. 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

    2010-01-01

    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 supplem...

  17. 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. PMID:26807952

  18. 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…

  19. 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…

  20. HDAC Inhibition Modulates Hippocampus-Dependent Long-Term Memory for Object Location in a CBP-Dependent Manner

    Haettig, Jakob; Stefanko, Daniel P.; Multani, Monica L.; Figueroa, Dario X.; McQuown, Susan C.; Wood, Marcelo A.

    2011-01-01

    Transcription of genes required for long-term memory not only involves transcription factors, but also enzymatic protein complexes that modify chromatin structure. Chromatin-modifying enzymes, such as the histone acetyltransferase (HAT) CREB (cyclic-AMP response element binding) binding protein (CBP), are pivotal for the transcriptional regulation…

  1. 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…

  2. 2010 Survey on long-term preservation of information and memory for geological disposal of radioactive waste

    Preservation of information and memory across generations is a cross-cutting theme of increasing importance for radioactive waste management. Because of the experience accumulated by the advanced national programmes that the RWMC represents, and the breadth of its related high-level initiatives, the Committee is uniquely placed internationally to combine resources and help develop state-of-the-art guidance on the long-term preservation of information and memory. In the context of fostering knowledge consolidation and transfer (KCT), the RWMC has already identified - in its reference document on KCT - the area of inter-generational transfer of knowledge as one of two areas needing development. In 2009, the RWMC decided to implement its programme of work in the area of information preservation and long-term memory as a series of projects or lines of actions opened by the RWMC and supervised by its Bureau. In order to better define its first series of projects the RWMC preformed a survey of its organisations needs and available materials and experience. At its meeting in 2010 the RWMC determined that the survey materials provided by organisations from 12 NEA countries constitute a good contribution to the literature in this field, and certainly to the upcoming projects. They provide as well a good baseline of information against which to measure progress a few years hence. This document reports the answers provided by organisations from 12 countries (Belgium, Canada, Finland, France, Hungary, Japan, Korea, Spain, Sweden, Switzerland, United Kingdom, and the USA,) to five questions related to long-term preservation of information and memory in the field of geological disposal. The questions are as follows: o What specific priority areas for long-term memory development have been identified in your agencies/countries? Which are the time scales of largest interest? o Do these priority proceed from good practice or/and from specific laws, regulations, policies exist in your country that set out requirements for long-term memory in long-term waste management? o How far advanced are you regarding establishing an action plan for long-term information and memory preservation in the field of geological disposal? Are you addressing the following RWMC questions: What information should be preserved? Why? Where? How should it be preserved? Which target groups? Which time horizons? What suggestions do you have for possible areas of focus for RWMC? (e.g. an international project that may assist Members?) What are the untapped areas that deserve more attention? Would you have studies, reports, policies that you might share with RWMC members? (author)

  3. 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. PMID:26868479

  4. Calcium/Calmodulin-dependent Protein Kinase II is a Ubiquitous Molecule in Human Long-term Memory Synaptic Plasticity: A Systematic Review

    Ataei, Negar; Sabzghabaee, Ali Mohammad; Movahedian, Ahmad

    2015-01-01

    Background: Long-term memory is based on synaptic plasticity, a series of biochemical mechanisms include changes in structure and proteins of brain's neurons. In this article, we systematically reviewed the studies that indicate calcium/calmodulin kinase II (CaMKII) is a ubiquitous molecule among different enzymes involved in human long-term memory and the main downstream signaling pathway of long-term memory. Methods: All of the observational, case–control and review studies were considered ...

  5. 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 learning and memory impairment in Lymnaea and buttress the hypothesis that lipid peroxidation-dependent depression of intrinsic excitability is a hallmark of normal neuronal aging. The data implicate both lipid peroxidation-dependent non-synaptic as well as apparently lipid peroxidation-independent synaptic mechanisms in the age-dependent decline in behavioural plasticity in this model system.

  6. The transcription factor MEF2 negatively regulates long-term memory formation and spine density in mice

    Christy J Cole

    2009-12-01

    Full Text Available The transcription factor myocyte enhancer factor-2 (MEF2 was originally identified and characterized in muscles. MEF2 is also highly expressed in the brain, but the function of neural MEF2 is virtually unexplored. Recent findings suggest that MEF2 negatively regulates dendritic spine formation and spine density. As the growth and restructuring of spines and synapses are thought to underlie memory formation, we examined the effects of manipulating MEF2 function on memory formation in mice. We assessed two type of memory that critically depend on different brain regions. Spatial memory involves the hippocampus, including the dentate gyrus whereas auditory fear conditioning involves the lateral amygdala. To increase MEF2 function in a region- and temporally-specific manner, we overexpressed a constitutively active form of MEF2 using a viral-mediated in vivo expression system. Increasing MEF2 function in dentate gyrus region before training in the Morris water maze disrupted spatial memory formation. This deficit was accompanied by a reduction in dendritic spine density. Conversely, expressing a dominant negative MEF2 repressor in the dentate gyrus increased spatial memory formation. The effects of MEF2 manipulation also generalized to the lateral amygdale where increasing MEF2 similarly disrupted the formation of long-term memory for auditory and contextual fear conditioning. Our findings suggest that MEF2 is important for the formation of two distinct forms of long-term memory perhaps by repressing new spine formation.

  7. 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. PMID:24009680

  8. 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), in particular declarative memory and aspects of procedural memory. Studies included in the review were identified following a systematic search of the literature and findings combined using meta-analysis. This review showed individuals with SLI are poorer than age matched controls in the learning and retrieval of verbal information from the declarative memory. However, there is evidence to sugge...

  9. Long-Term Effects of Neonatal Single or Multiple Isoflurane Exposures on Spatial Memory in Rats

    Murphy, Kathy L.; Baxter, Mark G

    2013-01-01

    General anesthetics are neurotoxic to neonatal rodents and non-human primates. Neonatal exposure to general anesthetics has been associated with long-term cognitive deficits in animal models. Some data from humans are consistent with long-term deleterious effects of anesthetic exposure early in life on cognitive development, with multiple exposures to general anesthetics being particularly damaging. We sought to determine whether repeated exposure of neonatal rats to anesthesia was associated...

  10. Long-term effects of neonatal single or multiple isoflurane exposures on spatial memory in rats

    MarkGBaxter; KathyLMurphy

    2013-01-01

    General anesthetics are neurotoxic to neonatal rodents and nonhuman primates. Neonatal exposure to general anesthetics has been associated with long-term cognitive deficits in animal models. Some data from humans are consistent with long-term deleterious effects of anesthetic exposure early in life on cognitive development, with multiple exposures to general anesthetics being particularly damaging. We sought to determine whether repeated exposure of neonatal rats to anesthesia was associated...

  11. Long-Term Effects of Neonatal Single or Multiple Isoflurane Exposures on Spatial Memory in Rats

    MarkGBaxter; KathyLMurphy

    2013-01-01

    General anesthetics are neurotoxic to neonatal rodents and nonhuman primates. Neonatal exposure to general anesthetics has been associated with long-term cognitive deficits in animal models. Some data from humans are consistent with long-term deleterious effects of anesthetic exposure early in life on cognitive development, with multiple exposures to general anesthetics being particularly damaging. We sought to determine whether repeated exposure of neonatal rats to anesthesia was associated...

  12. Differences in long-term memory stability and AmCREB level between forward and backward conditioned honeybees (Apis mellifera

    Dorothea Eisenhardt

    2015-04-01

    Full Text Available In classical conditioning a predictive relationship between a neutral stimulus (conditioned stimulus; CS and a meaningful stimulus (unconditioned stimulus; US is learned when the CS precedes the US. In backward conditioning the sequence of the stimuli is reversed. In this situation animals might learn that the CS signals the end or the absence of the US. In honeybees 30 min and 24 h following backward conditioning a memory for the excitatory and inhibitory properties of the CS could be retrieved, but it remains unclear whether a late long-term memory is formed that can be retrieved 72 h following backward conditioning. Here we examine this question by studying late long-term memory formation in forward and backward conditioning of the proboscis extension response (PER. We report a difference in the stability of memory formed upon forward and backward conditioning with the same number of conditioning trials. We demonstrate a transcription-dependent memory 72 h after forward conditioning but do not observe a 72 h memory after backward conditioning. Moreover we find that protein degradation is differentially involved in memory formation following these two conditioning protocols. We report differences in the level of a transcription factor, the cAMP response element binding protein (CREB known to induce transcription underlying long-term memory formation, following forward and backward conditioning. Our results suggest that these alterations in CREB levels might be regulated by the proteasome. We propose that the differences observed are due to the sequence of stimulus presentation between forward and backward conditioning and not to differences in the strength of the association of both stimuli.

  13. Differences in long-term memory stability and AmCREB level between forward and backward conditioned honeybees (Apis mellifera).

    Felsenberg, Johannes; Dyck, Yan; Feige, Janina; Ludwig, Jenny; Plath, Jenny Aino; Froese, Anja; Karrenbrock, Melanie; Nölle, Anna; Heufelder, Karin; Eisenhardt, Dorothea

    2015-01-01

    In classical conditioning a predictive relationship between a neutral stimulus (conditioned stimulus; CS) and a meaningful stimulus (unconditioned stimulus; US) is learned when the CS precedes the US. In backward conditioning the sequence of the stimuli is reversed. In this situation animals might learn that the CS signals the end or the absence of the US. In honeybees 30 min and 24 h following backward conditioning a memory for the excitatory and inhibitory properties of the CS could be retrieved, but it remains unclear whether a late long-term memory is formed that can be retrieved 72 h following backward conditioning. Here we examine this question by studying late long-term memory formation in forward and backward conditioning of the proboscis extension response (PER). We report a difference in the stability of memory formed upon forward and backward conditioning with the same number of conditioning trials. We demonstrate a transcription-dependent memory 72 h after forward conditioning but do not observe a 72 h memory after backward conditioning. Moreover we find that protein degradation is differentially involved in memory formation following these two conditioning protocols. We report differences in the level of a transcription factor, the cAMP response element binding protein (CREB) known to induce transcription underlying long-term memory formation, following forward and backward conditioning. Our results suggest that these alterations in CREB levels might be regulated by the proteasome. We propose that the differences observed are due to the sequence of stimulus presentation between forward and backward conditioning and not to differences in the strength of the association of both stimuli. PMID:25964749

  14. Chronic treatment with ginsenoside Rg1 promotes memory and hippocampal long-term potentiation in middle-aged mice.

    Zhu, G; Wang, Y; Li, J; Wang, J

    2015-04-30

    Ginseng serves as a potential candidate for the treatment of aging-related memory decline or memory loss. However, the related mechanism is not fully understood. In this study, we applied an intraperitoneal injection of ginsenoside Rg1, an active compound from ginseng in middle-aged mice and detected memory improvement and the underlying mechanisms. Our results showed that a period of 30-day administration of ginsenoside Rg1 enhanced long-term memory in the middle-aged animals. Consistent with the memory improvement, ginsenoside Rg1 administration facilitated weak theta-burst stimulation (TBS)-induced long-term potentiation (LTP) in acute hippocampal slices from middle-aged animals. Ginsenoside Rg1 administration increased the dendritic apical spine numbers and area in the CA1 region. In addition, ginsenoside Rg1 administration up-regulated the expression of hippocampal p-AKT, brain-derived neurotrophic factor (BDNF), proBDNF and glutamate receptor 1 (GluR1), but not p-ERK. Interestingly, the phosphatase and tensin homolog deleted on chromosome ten (PTEN) inhibitor (bpV) mimicked the ginsenoside Rg1 effects, including increasing p-AKT expression, promoting hippocampal basal synaptic transmission, LTP and memory. Taken together, our data suggest that ginsenoside Rg1 treatment improves memory in middle-aged mice possibly through regulating the PI3K/AKT pathway, altering apical spines and facilitating hippocampal LTP. PMID:25724866

  15. Long-term sampling of airborne bacteria and fungi into a non-evaporating liquid

    Lin, Xuejun; Reponen, Tiina A.; Willeke, Klaus; Grinshpun, Sergey A.; Foarde, Karin K.; Ensor, David S.

    Conventional sampling of bioaerosols into liquid impingers can only be performed with water or another low-viscosity liquid as the collection medium. Since these liquids evaporate quickly, sampling is generally limited to short-time periods of 15-30 min. In this study, our recently developed "BioSampler", has been used with a non-evaporating, higher viscosity liquid that does not kill nor grow microorganisms, and thus has been used to sample airborne bacteria and fungi for several hours. In side-by-side comparisons with the conventional AGI-30 impinger, sampling indoor air environments over short-time periods, the BioSampler yielded equivalent or higher culturable counts for bacteria and fungi than the AGI-30 when both samplers were operated for 30 min with 20 ml of phosphate buffer as the collection medium. The bio-efficiency of the AGI-30 decreased rapidly with sampling time until the liquid had evaporated after about 1 1/2 h. When the BioSampler was operated for 4 h with non-evaporating heavy white mineral oil, the collection efficiency decreased only moderately due to minimal reaerosolization of collected particles and gentle collection of the viable microorganisms. Samples obtained through long-term sampling with the BioSampler may detect culturable bacteria and fungi at lower ambient concentration levels than is possible through conventional liquid impingement sampling over short-time periods.

  16. Identification of gene expression changes associated with long-term memory of courtship rejection in Drosophila males.

    Winbush, Ari; Reed, Danielle; Chang, Peter L; Nuzhdin, Sergey V; Lyons, Lisa C; Arbeitman, Michelle N

    2012-11-01

    Long-term memory formation in Drosophila melanogaster is an important neuronal function shaping the insect's behavioral repertoire by allowing an individual to modify behaviors on the basis of previous experiences. In conditioned courtship or courtship suppression, male flies that have been repeatedly rejected by mated females during courtship advances are less likely than naïve males to subsequently court another mated female. This long-term courtship suppression can last for several days after the initial rejection period. Although genes with known functions in many associative learning paradigms, including those that function in cyclic AMP signaling and RNA translocation, have been identified as playing critical roles in long-term conditioned courtship, it is clear that additional mechanisms also contribute. We have used RNA sequencing to identify differentially expressed genes and transcript isoforms between naïve males and males subjected to courtship-conditioning regimens that are sufficient for inducing long-term courtship suppression. Transcriptome analyses 24 hours after the training regimens revealed differentially expressed genes and transcript isoforms with predicted and known functions in nervous system development, chromatin biology, translation, cytoskeletal dynamics, and transcriptional regulation. A much larger number of differentially expressed transcript isoforms were identified, including genes previously implicated in associative memory and neuronal development, including fruitless, that may play functional roles in learning during courtship conditioning. Our results shed light on the complexity of the genetics that underlies this behavioral plasticity and reveal several new potential areas of inquiry for future studies. PMID:23173095

  17. Robust on-line sampling and analysis during long-term perfusion cultivation of mammalian cells.

    Chong, LeeWey; Saghafi, Mehdi; Knappe, Christoph; Steigmiller, Stefan; Matanguihan, Cary; Goudar, Chetan T

    2013-05-20

    In an attempt to support robust automated sampling and analysis of mammalian cell bioreactors, an integrated platform, BaychroMA®, was developed which includes an innovative sterile sampling device, automated sample transport, a sample preparation module, online analyzers, and communication interfaces to process automation systems. The robustness of this platform was verified by applying it to a laboratory-scale perfusion bioreactor that was operated for over 100 days. Both manual and automated samples were collected over the course of the run and a comparison was made for cell density, viability, glucose, and lactate concentrations. The highest variability (14.4%) was seen for cell density estimates while those for viability, glucose, and lactate were 0.7, 12.9, and 8.2%, respectively. In addition, cell density set-point changes were made towards the end of the perfusion culture and the high frequency automated samples provided a higher resolution description of the dynamics of cell density change compared to less frequent manual sampling. Overall, our results indicate stable and robust operation of the BaychroMAT® platform in a long-term perfusion culture. This success should readily translate to shorter duration fed-batch cultures thereby enabling feed-back control based on real-time nutrient measurements. PMID:23545503

  18. Overexpression of SIRT6 in the hippocampal CA1 impairs the formation of long-term contextual fear memory.

    Yin, Xi; Gao, Yuan; Shi, Hai-Shui; Song, Li; Wang, Jie-Chao; Shao, Juan; Geng, Xu-Hong; Xue, Gai; Li, Jian-Li; Hou, Yan-Ning

    2016-01-01

    Histone modifications have been implicated in learning and memory. Our previous transcriptome data showed that expression of sirtuins 6 (SIRT6), a member of Histone deacetylases (HDACs) family in the hippocampal cornu ammonis 1 (CA1) was decreased after contextual fear conditioning. However, the role of SIRT6 in the formation of memory is still elusive. In the present study, we found that contextual fear conditioning inhibited translational expression of SIRT6 in the CA1. Microinfusion of lentiviral vector-expressing SIRT6 into theCA1 region selectively enhanced the expression of SIRT6 and impaired the formation of long-term contextual fear memory without affecting short-term fear memory. The overexpression of SIRT6 in the CA1 had no effect on anxiety-like behaviors or locomotor activity. Also, we also found that SIRT6 overexpression significantly inhibited the expression of insulin-like factor 2 (IGF2) and amounts of proteins and/or phosphoproteins (e.g. Akt, pAkt, mTOR and p-mTOR) related to the IGF2 signal pathway in the CA1. These results demonstrate that the overexpression of SIRT6 in the CA1 impaired the formation of long-term fear memory, and SIRT6 in the CA1 may negatively modulate the formation of contextual fear memory via inhibiting the IGF signaling pathway. PMID:26732053

  19. Overexpression of SIRT6 in the hippocampal CA1 impairs the formation of long-term contextual fear memory

    Yin, Xi; Gao, Yuan; Shi, Hai-Shui; Song, Li; Wang, Jie-Chao; Shao, Juan; Geng, Xu-Hong; Xue, Gai; Li, Jian-Li; Hou, Yan-Ning

    2016-01-01

    Histone modifications have been implicated in learning and memory. Our previous transcriptome data showed that expression of sirtuins 6 (SIRT6), a member of Histone deacetylases (HDACs) family in the hippocampal cornu ammonis 1 (CA1) was decreased after contextual fear conditioning. However, the role of SIRT6 in the formation of memory is still elusive. In the present study, we found that contextual fear conditioning inhibited translational expression of SIRT6 in the CA1. Microinfusion of lentiviral vector-expressing SIRT6 into theCA1 region selectively enhanced the expression of SIRT6 and impaired the formation of long-term contextual fear memory without affecting short-term fear memory. The overexpression of SIRT6 in the CA1 had no effect on anxiety-like behaviors or locomotor activity. Also, we also found that SIRT6 overexpression significantly inhibited the expression of insulin-like factor 2 (IGF2) and amounts of proteins and/or phosphoproteins (e.g. Akt, pAkt, mTOR and p-mTOR) related to the IGF2 signal pathway in the CA1. These results demonstrate that the overexpression of SIRT6 in the CA1 impaired the formation of long-term fear memory, and SIRT6 in the CA1 may negatively modulate the formation of contextual fear memory via inhibiting the IGF signaling pathway. PMID:26732053

  20. A long-term validation of the modernised DC-ARC-OES solid-sample method

    Florian, K. [Dept. of Chemistry, Technical University of Kosice (Slovakia); Hassler, J.; Foerster, O. [Elektroschmelzwerk GmbH, Kempten (Germany)

    2001-12-01

    The validation procedure based on ISO 17 025 standard has been used to study and illustrate both the long-term stability of the calibration process of the DC-ARC solid sample spectrometric method and the main validation criteria of the method. In the calculation of the validation characteristics depending on the linearity(calibration), also the fulfilment of predetermining criteria such as normality and homoscedasticity was checked. In order to decide whether there are any trends in the time-variation of the analytical signal or not, also the Neumann test of trend was applied and evaluated. Finally, a comparison with similar validation data of the ETV-ICP-OES method was carried out. (orig.)

  1. 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…

  2. Effects of Joint Attention on Long-Term Memory in 9-Month-Old Infants: An Event-Related Potentials Study

    Kopp, Franziska; Lindenberger, Ulman

    2011-01-01

    Joint attention develops during the first year of life but little is known about its effects on long-term memory. We investigated whether joint attention modulates long-term memory in 9-month-old infants. Infants were familiarized with visually presented objects in either of two conditions that differed in the degree of joint attention (high…

  3. Learning to never forget—time scales and specificity of long-term memory of a motor skill

    Se-Woong Park; Tjeerd Dijkstra; Dagmar Sternad

    2013-01-01

    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 ret...

  4. 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.

  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. Following the crowd: Brain Substrates of Long-Term Memory Conformity

    Edelson, Micah; Sharot, Tali; Dolan, Raymond J; Dudai, Yadin

    2011-01-01

    Human memory is strikingly susceptible to social influences, yet we know little about the underlying mechanisms. We examined how socially induced memory errors are generated in the brain by studying the memory of individuals exposed to recollections of others. Participants exhibited a strong tendency to conform to erroneous recollections of the group, producing both long-lasting and temporary errors, even when their initial memory was strong and accurate. Functional brain imaging revealed tha...

  7. Homologue of Protein Kinase M? 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 PKM?. Using antibodies to mammalian PKM?, 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 PKM? was confirmed with transcriptomics. We have demonstrated in behavioral experiments that contextual fear memory disappeared under a blockade of PKM? with a selective peptide blocker of PKM? (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 PKM? 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 PKM? molecules in somata of these identified neurons, as evidenced by immunochemistry. Obtained results suggest that the Helix homologue of PKM? might be involved in post-induction maintenance of long-term changes in the snail.

  8. 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 ...

  9. 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 ...

  10. 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.

  11. 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.

  12. 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…

  13. 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.

  14. 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.

  15. 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. (PsycINFO Database Record PMID:26709589

  16. The Representational Consequences of Intentional Forgetting: Impairments to Both the Probability and Fidelity of Long-Term Memory

    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. PMID:26709589

  17. Long-term memory-based control of attention in multi-step tasks requires working memory: Evidence from domain-specific interference

    RebeccaMartinaFoerster

    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 in...

  18. 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 in...

  19. Long-term phonological knowledge supports serial ordering in working memory.

    Nakayama, Masataka; Tanida, Yuki; Saito, Satoru

    2015-09-01

    Serial ordering mechanisms have been investigated extensively in psychology and psycholinguistics. It has also been demonstrated repeatedly that long-term phonological knowledge contributes to serial ordering. However, the mechanisms that contribute to serial ordering have yet to be fully understood. To understand these mechanisms, we demonstrate 2 effects using triples of Japanese nonwords in immediate serial recall. One, a type of bielement frequency effect, is a retrograde compatibility effect. Bielement frequency effects are well-established phenomena whereby a 2-element sequence (e.g., "ka-re") that frequently appears in a language instantiates better recall of any sequence that includes this element (e.g., "ka-re-su-mo"). We demonstrate that bielement frequency affected both the first (e.g., "ka" for "ka-re"; retrograde compatibility effect) and second part of a sequence, indicating the existence of minicontext representations of 2-element sequences. The other effects are the position-element(s) frequency effects, whereby an element (e.g., the mora "ka") that more frequently appears in 1 position of a sequence (e.g., in the first mora of a word) than in other positions facilitates better recall of that element (i.e., the first mora). The effects demonstrated in this article indicate the long-term associations of position representations and elements. These effects are discussed in terms of the extensive learning hypothesis, which assumes that phonological structures are learned gradually. Implications for computational models are also discussed. PMID:25730304

  20. Hypertension impairs hippocampus-related adult neurogenesis, CA1 neuron dendritic arborization and long-term memory.

    Shih, Y-H; Tsai, S-F; Huang, S-H; Chiang, Y-T; Hughes, M W; Wu, S-Y; Lee, C-W; Yang, T-T; Kuo, Y-M

    2016-05-13

    Hypertension is associated with neurodegenerative diseases and cognitive impairment. Several studies using spontaneous hypertensive rats to study the effect of hypertension on memory performance and adult hippocampal neurogenesis have reached inconsistent conclusions. The contradictory findings may be related to the genetic variability of spontaneous hypertensive rats due to the conventional breeding practices. The objective of this study is to examine the effect of hypertension on hippocampal structure and function in isogenic mice. Hypertension was induced by the '2 kidneys, 1 clip' method (2K1C) which constricted one of the two renal arteries. The blood pressures of 2K1C mice were higher than the sham group on post-operation day 7 and remained high up to day 28. Mice with 2K1C-induced hypertension had impaired long-term, but not short-term, memory. Dendritic complexity of CA1 neurons and hippocampal neurogenesis were reduced by 2K1C-induced hypertension on post-operation day 28. Furthermore, 2K1C decreased the levels of hippocampal brain-derived neurotrophic factor, while blood vessel density and activation status of astrocytes and microglia were not affected. In conclusion, hypertension impairs hippocampus-associated long-term memory, dendritic arborization and neurogenesis, which may be caused by down-regulation of brain-derived neurotrophic factor signaling pathways. PMID:26921651

  1. Electrical stunning and hibernation: suggestion of new terms for short- and long-term cardiac memory.

    Zoghi, Mehdi; Nalbantgil, Sanem

    2004-09-01

    Persistent T wave changes following resumption of sinus rhythm induced by pacing or arrhythmias that cause altering of ventricular activation sequence are named "cardiac memory". After this initial definition there has been a discussion whether such T wave changes are primary, secondary or pseudoprimary. In addition according to the results of pathophysiological studies investigating the mechanism and nature of this repolarization abnormality some authors have preferred to use the term "electrical remodelling" instead of cardiac memory. But these two terms are still not well defined. In this article, the previous terms are discussed and a new term instead of cardiac memory is introduced. PMID:15294266

  2. Memory and learning sequelae in long-term survivors of acute lymphoblastic leukemia: Association with attention deficits

    A systematic study of verbal and nonverbal memory and learning was undertaken in long-term survivors of acute lymphoblastic leukemia to assess the incidence and pattern of impairments and to determine the relationship between these deficits and computed tomography (CT) brain scan abnormalities. Twenty-three children who had received cranial irradiation (2,400 cGy) and intrathecal chemotherapy as central nervous system (CNS) preventive therapy and who were off all therapy for at least 4 years were evaluated. On the basis of their CT brain scan findings, patients were divided into three groups: those with intracerebral calcifications (n = 5), those with cortical atrophy (n = 8), and those with normal CT findings (n = 10). Significant deficits in verbal memory (p less than 0.025) and verbal learning (p less than 0.05) were observed that were associated with the presence and type of CT brain scan abnormalities; the greatest impairments were observed in patients with calcifications. No significant differences between CT scan groups were found for nonverbal memory and learning. Previous evaluation of attentional processing in these patients using reaction time tests had revealed the presence of deficits primarily in the ability to sustain attention. Combining those data with findings from the present study showed that memory impairments, particularly those in short-term memory, were primarily attributable to an underlying attentional defect that affect the encoding stage of memory processing

  3. ?1-and ?2-adrenoceptors in hippocampal CA3 region are required for long-term memory consolidation in rats.

    Zheng, Jian; Luo, Fei; Guo, Nan-Nan; Cheng, Zong-Yue; Li, Bao-Ming

    2015-11-19

    The existence of ?-adrenoceptors (ARs) in the hippocampus and the importance of ?-ARs in regulating synaptic plasticity and learning/memory function are well documented. As known, ?-ARs in area cornu ammonis 1 (CA1) are involved in regulating memory consolidation. However, little is known about the functional roles of the ?-ARs subtypes, ?1- and ?2-ARs, in the hippocampal cornu ammonis 3 (CA3) region. To address this question, we firstly locally infused the ?1- or ?2-ARs antagonist into the CA3 region and observed that blockage of either ?1-AR or ?2-AR impaired long-term contextual fear memory and water-maze spatial memory. We also found that, following the contextual fear conditioning, the expression of ?1-AR in the CA3 region significantly increased, whereas ?2-AR was unchanged. Then intra-CA3 infusion of recombinant lentiviral RNAi vectors for ?1 or ?2-ARs also produced deficit in contextual memory consolidation. Taken together, the results suggested that the ?1- and ?2-ARs in the CA3 region were involved in hippocampus dependent memory consolidation. PMID:26343545

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

    Zeelenberg, René; Pecher, Diane

    2002-01-01

    Semantic priming effects are usually obtained only if the prime is presented shortly before the target stimulus. Recent evidence obtained with the so-called false memory paradigm suggests, however, that in both explicit and implicit memory tasks semantic relations between words can result in long-lasting effects when multiple 'primes' are presented. The aim of the present study was to investigate whether these effects would generalize to lexical decision. In four experiments we showed that ev...

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

    Altenmüller Eckart O; Münte Thomas F; Eschrich Susann

    2008-01-01

    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 investiga...

  6. Does stress remove the HDAC brakes for the formation and persistence of long-term memory?

    White, André O.; Wood, Marcelo A.

    2013-01-01

    It has been known for numerous decades that gene expression is required for long-lasting forms of memory. In the past decade, the study of epigenetic mechanisms in memory processes has revealed yet another layer of complexity in the regulation of gene expression. Epigenetic mechanisms do not only provide complexity in the protein regulatory complexes that control coordinate transcription for specific cell function, but the epigenome encodes critical information that integrates experience and ...

  7. Effects of long term administration of testosterone and estradiol on spatial memory in rats

    Mohammadi-Farani, Ahmad; Haghighi, Arash; Ghazvineh, Milad

    2015-01-01

    There are many discrepancies around the effect of sex hormones on spatial learning and memory in rodents. The aim of the present study was to investigate the effects of chronic administration of estradiol (ES) and testosterone (TES) on spatial memory in adult castrated male rats. Cholinesterase activity of the hippocampus in treated animals was also measured to seek if hormonal treatment can change the acetylcholinesterase (AChE) activity in this region. Six groups of castrated male rats rece...

  8. Stress administered prior to encoding impairs neutral but enhances emotional long-term episodic memories

    Payne, Jessica D.; Jackson, Eric D.; Hoscheidt, Siobhan; Ryan, Lee; Jacobs, W. Jake; Nadel, Lynn

    2007-01-01

    Stressful events frequently comprise both neutral and emotionally arousing information, yet the impact of stress on emotional and neutral events is still not fully understood. The hippocampus and frontal cortex have dense concentrations of receptors for stress hormones, such as cortisol, which at high levels can impair performance on hippocampally dependent memory tasks. Yet, the same stress hormones can facilitate memory for emotional information, which involves interactions between the hipp...

  9. Autobiographical memory in long-term survivors of severe traumatic brain injury.

    Knight, Robert G; O'Hagan, Kimberley

    2009-07-01

    The aim of this study was to examine the ability of persons who had sustained a severe traumatic brain injury (TBI) at least 6 years previously to recall memories associated with famous names. Each of 19 persons with TBI was matched with a healthy control of the same age, gender, and occupational-educational background. A list of 115 names of famous people was compiled, 25 of whom came to prominence in each decade from 1960 to 1999, and 15 in the period 2000 to 2005. Participants were first asked whether they recognized each name as being of a famous person and to state the reason for the individual's fame. For those names they correctly identified, they were asked to recall a memory associated with the person; each memory produced was categorized as a context-specific memory or a general memory. The ability to recognize and identify famous names was well preserved in the TBI group; however, they showed a consistent impairment in the ability to recall specific episodic memories acquired before and after the date of the TBI. This inability to generate personal and specific information is likely to have an impact on the ability of the person with TBI to participate in interpersonal interactions and problem solve in complex social situations. PMID:18972310

  10. The effects of long-term stress on neural dynamics of working memory processing: An investigation using ERP.

    Yuan, Yiran; Leung, Ada W S; Duan, Hongxia; Zhang, Liang; Zhang, Kan; Wu, Jianhui; Qin, Shaozheng

    2016-01-01

    This study examined the neural dynamics of working memory (WM) processing under long-term stress. Forty participants who had been exposed to a long period of major exam preparation (six months) and twenty-one control participants performed a numerical n-back task (n = 1, 2) while electroencephalograms were recorded. Psychological and endocrinal measurements confirmed significantly higher levels of long-term stress for participants in the exam group. The exam group showed significantly increased P2 amplitude in the frontal-central sites in the 1-back and 2-back conditions, whereas other ERP components, including the P1, N1 and P3 and behavioral performance, were unchanged. Notably, the P2 effect was most pronounced in participants in the exam group who reported perceiving high levels of stress. The perceived stress scores positively correlated with the P2 amplitude in the 1-back and 2-back conditions. These results suggest that long-term stress has an impact on attention and the initiation of the updating process in WM. PMID:27000528

  11. The effects of long-term stress on neural dynamics of working memory processing: An investigation using ERP

    Yuan, Yiran; Leung, Ada W. S.; Duan, Hongxia; Zhang, Liang; Zhang, Kan; Wu, Jianhui; Qin, Shaozheng

    2016-01-01

    This study examined the neural dynamics of working memory (WM) processing under long-term stress. Forty participants who had been exposed to a long period of major exam preparation (six months) and twenty-one control participants performed a numerical n-back task (n = 1, 2) while electroencephalograms were recorded. Psychological and endocrinal measurements confirmed significantly higher levels of long-term stress for participants in the exam group. The exam group showed significantly increased P2 amplitude in the frontal-central sites in the 1-back and 2-back conditions, whereas other ERP components, including the P1, N1 and P3 and behavioral performance, were unchanged. Notably, the P2 effect was most pronounced in participants in the exam group who reported perceiving high levels of stress. The perceived stress scores positively correlated with the P2 amplitude in the 1-back and 2-back conditions. These results suggest that long-term stress has an impact on attention and the initiation of the updating process in WM.

  12. Contextual consistency facilitates long-term memory of perceptual detail in barely seen images.

    Gronau, Nurit; Shachar, Meytal

    2015-08-01

    It is long known that contextual information affects memory for an object's identity (e.g., its basic level category), yet it is unclear whether schematic knowledge additionally enhances memory for the precise visual appearance of an item. Here we investigated memory for visual detail of merely glimpsed objects. Participants viewed pairs of contextually related and unrelated stimuli, presented for an extremely brief duration (24 ms, masked). They then performed a forced-choice memory-recognition test for the precise perceptual appearance of 1 of 2 objects within each pair (i.e., the "memory-target" item). In 3 experiments, we show that memory-target stimuli originally appearing within contextually related pairs are remembered better than targets appearing within unrelated pairs. These effects are obtained whether the target is presented at test with its counterpart pair object (i.e., when reiterating the original context at encoding) or whether the target is presented alone, implying that the contextual consistency effects are mediated predominantly by processes occurring during stimulus encoding, rather than during stimulus retrieval. Furthermore, visual detail encoding is improved whether object relations involve implied action or not, suggesting that, contrary to some prior suggestions, action is not a necessary component for object-to-object associative "grouping" processes. Our findings suggest that during a brief glimpse, but not under long viewing conditions, contextual associations may play a critical role in reducing stimulus competition for attention selection and in facilitating rapid encoding of sensory details. Theoretical implications with respect to classic frame theories are discussed. (PsycINFO Database Record PMID:26010591

  13. 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…

  14. 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…

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

    Vindeløv, L L; Christensen, I J; Keiding, N; Spang-Thomsen, M; Nissen, N I

    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...

  16. 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

  17. 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.

  18. Sleep-dependent memory consolidation and neurofeedback in insomnia - A long-term study

    Manuel Schabus

    2015-02-01

    Current results indicate that healthy as well as insomnia patients do show associations of (overnight memory performance and (fast sleep spindle activity and interestingly are even able to increase these spindles by means of instrumental 12-15Hz EEG conditioning. Research was supported by FWF research grants (P-21154-B18; I-934 from the Austrian Science Foundation.

  19. Lead (Pb+2) impairs long-term memory and blocks learning-induced increases in hippocampal protein kinase C activity

    The long-term storage of information in the brain known as long-term memory (LTM) depends on a variety of intracellular signaling cascades utilizing calcium (Ca2+) and cyclic adenosine monophosphate as second messengers. In particular, Ca+2/phospholipid-dependent protein kinase C (PKC) activity has been proposed to be necessary for the transition from short-term memory to LTM. Because the neurobehavioral toxicity of lead (Pb+2) has been associated to its interference with normal Ca+2 signaling in neurons, we studied its effects on spatial learning and memory using a hippocampal-dependent discrimination task. Adult rats received microinfusions of either Na+ or Pb+2 acetate in the CA1 hippocampal subregion before each one of four training sessions. A retention test was given 7 days later to examine LTM. Results suggest that intrahippocampal Pb+2 did not affect learning of the task, but significantly impaired retention. The effects of Pb+2 selectively impaired reference memory measured in the retention test, but had no effect on the general performance because it did not affect the latency to complete the task during the test. Finally, we examined the effects of Pb+2 on the induction of hippocampal Ca+2/phospholipid-dependent PKC activity during acquisition training. The results showed that Pb+2 interfered with the learning-induced activation of Ca+2/phospholipid-dependent PKC on day 3 of acquisition. Overall, our results indicate that Pb+2 causes cognitive impairments in adult rats and that such effects might be subserved by interference with Ca+2-related signaling mechanisms required for normal LTM

  20. Using the context preexposure facilitation effect to study long-term context memory in preweanling, juvenile, adolescent, and adult rats.

    Robinson-Drummer, Patrese A; Stanton, Mark E

    2015-09-01

    The present study used the context preexposure facilitation effect (CPFE) to examine long-term retention of incidental context learning in periweanling, adolescent and adult rats. The CPFE is a variant of contextual fear conditioning in which encoding the context representation, associating this representation with shock, and expressing the context-shock association each occur on separate occasions. Experiment 1 manipulated the retention interval-1d, 8d, 15d, or 22d-between context preexposure and training with immediate shock to determine how long the encoded context could be remembered (testing always occurred 24h following training). The other factors were age-postnatal day (PND) 24 vs 31-and training group-Preexposed to the training context (Pre) vs. an alternate context (Alt-Pre). At both ages, significantly more freezing was evident in the Pre vs. Alt Pre Groups at the 24h, 8d and 15d retention intervals but not at the 22d interval, indicating that juvenile-adolescent rats remember the context for up to 15d. In contrast, context memory persists for 22days in adult rats (Experiment 2); and is not evident after 24h, 8d, or 15d retention intervals in PND 17 rats (Experiment 3). The present study illustrates the value of the CPFE paradigm for investigations of long-term context memory in developing rats. Implications for the neurobiology of infantile amnesia are discussed. PMID:25542890

  1. An optical model for implementing Parrondo’s game and designing stochastic game with long-term memory

    Highlights: ? Using a photon propagating through a designed array of beam splitters to simulate Parrondo’s game paradox. ? Design the optical flowchart for implementing Parrondo history-dependent game paradox. ? Design new game with long-term memory on a designed tree lattice and loop lattice. - Abstract: An optical model for a photon propagating through a designed array of beam splitters is developed to give a physical implementation of Parrondo’s game and Parrondo’s history-dependent game. The winner in this optical model is a photon passed the beam splitter. The loser is a photon being reflected by the beam splitter. The optical beam splitter is the coin-tosser. We designed new games with long-term memory by using this optical diagram method. The optical output of the combined game of two losing games could be a win, or a loss, or an oscillation between win and loss. The modern technology to implement this optical model is well developed. A circularly polarized photon is a possible candidate for this physical implementation in laboratory.

  2. Ginsenoside Rg1 ameliorates hippocampal long-term potentiation and memory in an Alzheimer's disease model.

    Li, Fengling; Wu, Xiqing; Li, Jing; Niu, Qingliang

    2016-06-01

    The complex etiopathogenesis of Alzheimer's disease (AD) has limited progression in the identification of effective therapeutic agents. Amyloid precursor protein (APP) and presenilin‑1 (PS1) are always overexpressed in AD, and are considered to be the initiators of the formation of β‑amyloid plaques and the symptoms of AD. In the present study, a transgenic AD model, constructed via the overexpression of APP and PS1, was used to verify the protective effects of ginsenoside Rg1 on memory performance and synaptic plasticity. AD mice (6‑month‑old) were treated via intraperitoneal injection of 0.1‑10 mg/kg ginsenoside Rg1. Long‑term memory, synaptic plasticity, and the levels of AD‑associated and synaptic plasticity‑associated proteins were measured following treatment. Memory was measured using a fear conditioning task and protein expression levels were investigated using western blotting. All the data was analyzed by one-way analysis of variance or t‑test. Following 30 days of consecutive treatment, memory in the AD mouse model was ameliorated in the 10 mg/kg ginsenoside Rg1 treatment group. As demonstrated by biochemical experiments, ginsenoside Rg1 treatment reduced the accumulations of β‑amyloid 1‑42 and phosphorylated (p)‑Tau in the AD model. Additionally, brain-derived neurotrophic factor (BDNF) and p‑TrkB synaptic plasticity‑associated proteins were upregulated following ginsenoside Rg1 application. Correspondingly, long‑term potentiation (LTP) was restored following ginsenoside Rg1 application in the AD mice model. Taken together, ginsenoside Rg1 repaired hippocampal LTP and memory, likely through facilitating the clearance of AD‑associated proteins and through activation of the BDNF‑TrkB pathway. Therefore, ginsenoside Rg1 may be a candidate drug for the treatment of AD. PMID:27082952

  3. Postischemic PKC activation rescues retrograde and anterograde long-term memory

    Sun, Miao-Kun; Hongpaisan, Jarin; Alkon, Daniel L.

    2009-01-01

    Therapeutics for cerebral ischemia/hypoxia, which often results in ischemic stroke in humans, are a global unmet medical need. Here, we report that bryostatin-1, a highly potent protein kinase C (PKC) activator, interrupts pathophysiological molecular cascades and apoptosis triggered by cerebral ischemia/hypoxia, enhances neurotrophic activity, and induces synaptogenesis in rats. This postischemic therapeutic approach is further shown to preserve learning and memory capacity even 4 months lat...

  4. A requirement for memory retrieval during and after long-term extinction learning

    Ouyang, Ming; Thomas, Steven A.

    2005-01-01

    Current learning theories are based on the idea that learning is driven by the difference between expectations and experience (the delta rule). In extinction, one learns that certain expectations no longer apply. Here, we test the potential validity of the delta rule by manipulating memory retrieval (and thus expectations) during extinction learning. Adrenergic signaling is critical for the time-limited retrieval (but not acquisition or consolidation) of contextual fear. Using genetic and pha...

  5. 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 Workin...

  6. PKMzeta Maintains Spatial, Instrumental, and Classically Conditioned Long-Term Memories

    Serrano, P.; Friedman, E.L.; Kenney, Jana; Taubenfeld, S.M.; Zimmerman, J.M.; Hanna, J.; Alberini, C.; Kelley, A.E.; Maren, S.; Rudy, J.W.; Yin, J.C.P.; Sacktor, T.C.; Fenton, A.A.

    2008-01-01

    Roč. 6, č. 12 (2008), s. 2698-2706. ISSN 1544-9173 R&D Projects: GA MŠk(CZ) 1M0517; GA MŠk(CZ) LC554; GA ČR(CZ) GA309/06/1231 Institutional research plan: CEZ:AV0Z50110509 Keywords : PKMzeta * memory * LTP Subject RIV: FH - Neurology Impact factor: 12.683, year: 2008

  7. Chronic administration of sulbutiamine improves long term memory formation in mice: possible cholinergic mediation.

    Micheau, J; Durkin, T P; Destrade, C; Rolland, Y; Jaffard, R

    1985-08-01

    Thiamine deficiency in both man and animals is known to produce memory dysfunction and cognitive disorders which have been related to an impairment of cholinergic activity. The present experiment was aimed at testing whether, inversely, chronic administration of large doses of sulbutiamine would have a facilitative effect on memory and would induce changes in central cholinergic activity. Accordingly mice received 300 mg/kg of sulbutiamine daily for 10 days. They were then submitted to an appetitive operant level press conditioning test. When compared to control subjects, sulbutiamine treated mice learned the task at the same rate in a single session but showed greatly improved performance when tested 24 hr after partial acquisition of the same task. Parallel neurochemical investigations showed that the treatment induced a slight (+ 10%) but significant increase in hippocampal sodium-dependent high affinity choline uptake. The present findings and previous results suggest that sulbutiamine improves memory formation and that this behavioral effect could be mediated by an increase in hippocampal cholinergic activity. PMID:4059305

  8. NMR-based metabonomics of bovine blood: an investigation into the effects of long term storage on plasma samples

    Trabi, M.; Keller, M.D.; JONSSON, N

    2013-01-01

    Freezers in research institutions often contain a plethora of samples left over from studies performed years or even decades ago. Along with samples stored in biobanks, these could prove to be treasure troves for metabonomic research. Although the influence of sample handling and short to medium term storage on conventionally determined blood parameters has been reported, little is known about the effects of long term storage (years to decades) on plasma samples. The aim of this study was to ...

  9. 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. PMID:26802564

  10. Early shifts of brain metabolism by caloric restriction preserve white matter integrity and long-term memory in aging mice

    Ai-Ling Lin

    2015-11-01

    Full Text Available Preservation of brain integrity with age is highly associated with lifespan determination. Caloric restriction (CR has been shown to increase longevity and healthspan in various species; however, its effects on preserving living brain functions in aging remain largely unexplored. In the study, we used multimodal, non-invasive neuroimaging (PET/MRI/MRS to determine in vivo brain glucose metabolism, energy metabolites, and white matter structural integrity in young and old mice fed with either control or 40% CR diet. In addition, we determined the animals’ memory and learning ability with behavioral assessments. Blood glucose, blood ketone bodies, and body weight were also measured. We found distinct patterns between normal aging and CR aging on brain functions - normal aging showed reductions in brain glucose metabolism, white matter integrity, and long-term memory, resembling human brain aging. CR aging, in contrast, displayed an early shift from glucose to ketone bodies metabolism, which was associated with preservations of brain energy production, white matter integrity, and long-term memory in aging mice. Among all the mice, we found a positive correlation between blood glucose level and body weight, but an inverse association between blood glucose level and lifespan. Our findings suggest that CR could slow down brain aging, in part due to the early shift of energy metabolism caused by lower caloric intake, and we were able to identify the age-dependent effects of CR non-invasively using neuroimaging. These results provide a rationale for CR-induced sustenance of brain health with extended longevity.

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

    Agustina Falibene

    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.

  12. The development of the abilities to acquire novel detailed orthographic representations and maintain them in long-term memory.

    Binamé, Florence; Poncelet, Martine

    2016-03-01

    Previous studies have clearly demonstrated that the development of orthographic representations relies on phonological recoding. However, substantial questions persist about the remaining unexplained variance in the acquisition of word-specific orthographic knowledge that is still underspecified. The main aim of this study was to explore whether two cognitive factors-sensitivity to orthographic regularities and short-term memory (STM) for serial order-make independent contributions to the acquisition of novel orthographic representations beyond that of the phonological core component and the level of preexisting word-specific orthographic knowledge. To this end, we had children from second to sixth grades learn novel written word forms using a repeated spelling practice paradigm. The speed at which children learned the word forms and their long-term retention (1week and 1month later) were assessed. Hierarchical regression analyses revealed that phonological recoding, preexisting word-specific orthographic knowledge, and order STM explained a portion of the variance in orthographic learning speed, whereas phonological recoding, preexisting word-specific orthographic knowledge, and orthographic sensitivity each explained a portion of variance in the long-term retention of the newly created orthographic representations. A secondary aim of the study was to determine the developmental trajectory of the abilities to acquire novel orthographic word forms over the course of primary schooling. As expected, results showed an effect of age on both learning speed and long-term retention. The specific roles of orthographic sensitivity and order STM as independent factors involved in different steps of orthographic learning are discussed. PMID:26600080

  13. 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. PMID:26617545

  14. 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 visuospatial memory indicated by lower BVMT-R scores.Conclusion: Infant exposure to earthquake-related stress impairs visuospatial memory in adulthood. Fetuses in the middle and late stages of development are more vulnerable to stress-induced damage that consequently results in impaired visuospatial memory. Education and early-life trauma can also influence the performance of working memory in adulthood. Keywords: Tangshan earthquake, early life stress, working memory, chronic effect

  15. Stress hormone action: corticosterone determines the strength of long-term fear memory dependent on the mouse genotype

    Anastasia Diamantopoulou

    2009-06-01

    Full Text Available Post-traumatic stress disorder (PTSD is characterized by strong, uncontrolled memories of the negative event, not prone to extinction. Corticosterone, the glucocorticoid secreted in response to stress in rodents, either strengthened or weakened emotional memory processing during 4 days, depending on (i the genetic background of the mice (C57BL/6J; BALB/c and (ii the spatio-temporal context of its action (Brinks et al. ExpNeurol.2009. (BALB/c: increased corticosterone-stress response and emotionality compared to C57BL/6J. Using the Pavlovian fear conditioning paradigm of alternating cue/context exposures, we assessed the persistence of fear memories (expressed as freezing. BALB/c mice exhibited enhanced fear memory compared to the C57BL/6J, which decays over time. Re-exposure to the fear-related environment on days 15 and 16 after acquisition, favored extinction of fear memory in C57BL/6J mice on days 52 and 53, which was not the case for the BALB/c. Corticosterone (250 ìg/kg, i.p. 5 minutes before acquisition in C57BL/6J specifically facilitated memory for context related fear, opposing the extinction-favoring effects of prior re-exposure sessions. However, BALB/c mice treated with corticosterone, directly after acquisition exhibited reduced freezing during cue and context episodes on days 52 and 53, enhanced time-dependent cue fear memory decay and abolished the context-cue distinction ability. We conclude that corticosterone prior to stress in C57BL/6J mice strengthened consolidation of contextual stress-associated signals, resulting in sustained long-term fear memory: relevant for preventing the development of stress related disorders such as PTSD. Corticosterone in BALB/c mice destabilized consolidation and predominantly strongly decreased cue-related fear memories: this will allow studying therapeutic treatments. Supported by KNAW-Dobberke Stichting 2007-07(VB, IRTG NWO-DN95-420(MSO, Brain Foundation Netherlands 2008(1-38(MSO,AD, NENS(AD.

  16. 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.

  17. A Dynamical Model for Information Retrieval and Emergence of Scale-Free Clusters in a Long Term Memory Network

    Licata, Ignazio

    2010-01-01

    The classical forms of knowledge representation fail when a strong dynamical interconnection between system and environment comes into play. We propose here a model of information retrieval derived from the Kintsch-Ericsson scheme, based upon a long term memory (LTM) associative net whose structure changes in time according to the textual content of the analyzed documents. Both the theoretical analysis carried out by using simple statistical tools and the tests show the appearing of typical power-laws and the net configuration as a scale-free graph. The information retrieval from LTM shows that the entire system can be considered to be an information amplifier which leads to the emergence of new cognitive structures. It has to be underlined that the expanding of the semantic domain regards the user-network as a whole system.

  18. 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; Dabelsteen, Torben

    Most domestic dogs are subjected to some kind of obedience training, often on a frequent basis, but the question of how often and for how long a dog should be trained has not been fully investigated. Optimizing the training as much as possible is not only an advantage in the training of working...... 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...... operant conditioning and shaping to perform a traditional obedience task, each dog having a total of 18 training sessions. The training schedules of the 4 groups differentiated in frequency (1–2 times per week vs. daily) and duration (1 training session vs. 3 training sessions in a row). Acquisition was...

  19. 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; Dabelsteen, Torben

    operant conditioning and shaping to perform a traditional obedience task, each dog having a total of 18 training sessions. The training schedules of the 4 groups differentiated in frequency (1–2 times per week vs. daily) and duration (1 training session vs. 3 training sessions in a row). Acquisition was...... 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...... measured as achieved training level at a certain time. The dogs’ retention of the task was tested four weeks post-acquisition. Results demonstrated that dogs trained 1–2 times per week had significantly better acquisition than daily trained dogs, and that dogs trained only 1 session a day had significantly...

  20. Ipsilateral hippocampal atrophy is associated with long-term memory dysfunction after ischemic stroke in young adults.

    Schaapsmeerders, Pauline; van Uden, Inge W M; Tuladhar, Anil M; Maaijwee, Noortje A M; van Dijk, Ewoud J; Rutten-Jacobs, Loes C A; Arntz, Renate M; Schoonderwaldt, Hennie C; Dorresteijn, Lucille D A; de Leeuw, Frank-Erik; Kessels, Roy P C

    2015-07-01

    Memory impairment after stroke in young adults is poorly understood. In elderly stroke survivors memory impairments and the concomitant loss of hippocampal volume are usually explained by coexisting neurodegenerative disease (e.g., amyloid pathology) in interaction with stroke. However, neurodegenerative disease, such as amyloid pathology, is generally absent at young age. Accumulating evidence suggests that infarction itself may cause secondary neurodegeneration in remote areas. Therefore, we investigated the relation between long-term memory performance and hippocampal volume in young patients with first-ever ischemic stroke. We studied all consecutive first-ever ischemic stroke patients, aged 18-50 years, admitted to our academic hospital center between 1980 and 2010. Episodic memory of 173 patients was assessed using the Rey Auditory Verbal Learning Test and the Rey Complex Figure and compared with 87 stroke-free controls. Hippocampal volume was determined using FSL-FIRST, with manual correction. On average 10 years after stroke, patients had smaller ipsilateral hippocampal volumes compared with controls after left-hemispheric stroke (5.4%) and right-hemispheric stroke (7.7%), with most apparent memory dysfunctioning after left-hemispheric stroke. A larger hemispheric stroke was associated with a smaller ipsilateral hippocampal volume (b=-0.003, P<0.0001). Longer follow-up duration was associated with smaller ipsilateral hippocampal volume after left-hemispheric stroke (b=-0.028 ml, P=0.002) and right-hemispheric stroke (b=-0.015 ml, P=0.03). Our results suggest that infarction is associated with remote injury to the hippocampus, which may lower or expedite the threshold for cognitive impairment or even dementia later in life. PMID:25757914

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

    Karabanov, Anke Ninija; Paine, Rainer; Chao, Chi Chao; Schulze, Katrin; Scott, Brian; Hallett, Mark; Mishkin, Mortimer

    2015-01-01

    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. PMID:25815813

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

    AshleighMonetteMaxcey; GeoffreyF.Woodman

    2014-01-01

    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 pr...

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

    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

  4. 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.

  5. 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, this hypothesis would provide a mechanism through which the skeleton could be pharmacologically primed to enhance or retrieve the normal osteogenic response to exercise. This would form a basis through which novel therapies could be developed to target osteoporosis and other prevalent bone disorders associated with low bone mass.

  6. Episodic Long-Term Memory of Spoken Discourse Masked by Speech: What Is the Role for Working Memory Capacity?

    Sorqvist, Patrik; Ronnberg, Jerker

    2012-01-01

    Purpose: To investigate whether working memory capacity (WMC) modulates the effects of to-be-ignored speech on the memory of materials conveyed by to-be-attended speech. Method: Two tasks (reading span, Daneman & Carpenter, 1980; Ronnberg et al., 2008; and size-comparison span, Sorqvist, Ljungberg, & Ljung, 2010) were used to measure individual…

  7. 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…

  8. 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…

  9. 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…

  10. Groundwater sampling from borehole KR6 during long-term pumping test at olkiluoto, Eurajoki in 2002

    A long-term pumping test from borehole KR6 at Olkiluoto was initiated in 2001. Both flow and in situ EC measurements as well as groundwater samplings from specific sections are being performed. The aim is to get information on the potential connections via fractures both to the sea and to the deep saline groundwater during long term pumping of the borehole. In 2002 and at the beginning of 2003 six groundwater samples were collected from borehole KR6 at three different sampling depths (98,5-100,5 m, 125-130 m and 135-137 m). Groundwater samples were taken from the packed-off sections by a membrane pump. Salinities of two groundwater samples from depths 98,5-100,5 m and 135-137 m were increasing due to the long term pumping of the borehole KR6. Whereas the salinity of the groundwater samples taken from section 125-130 m was decreasing between two groundwater samplings done in 2002. All taken groundwater samples represent water type Na-Ca-Cl and they are brackish (1 000 mg/l < TDS< 10 000 mg/l). Electrical conductivity, which was measured during the groundwater sampling, was compared to the in situ electrical conductivity measurements. The results achieved with different methods agreed well except for one sample. Based on EC results it can be concluded that groundwater samples taken from borehole KR6 represent good groundwater from a single fracture or narrow fracture zone. This study presents sampling methods and the results of analyses of groundwater samples from the deep borehole KR6. Beside these the report presents operating principles of the in situ EC measurements and also comparison of the results to the EC results measured during groundwater sampling. This report also contains a short comparison of the groundwater sampling results achieved in 2002 and 2003. (orig.)

  11. Impairment in material-specific long-term memory following unilateral mediodorsal thalamic damage and presumed partial disconnection of the mammillo-thalamic tract.

    Edelstyn, Nicola M J; Mayes, Andrew R; Denby, Christine; Ellis, Simon J

    2012-03-01

    Neuropsychological findings suggest material-specific lateralization of the medial temporal lobe's role in long-term memory, with greater left-sided involvement in verbal memory, and greater right-sided involvement in visual memory. Whether material-specific lateralization of long-term memory also extends to the anteromedial thalamus remains uncertain. We report two patients with unilateral right (OG) and left (SM) mediodorsal thalamic pathology plus probable correspondingly lateralized damage of the mammillo-thalamic tract. The lesions were mapped using high-resolution structural magnetic resonance imaging and schematically reconstructed. Mean absolute volume estimates for the mammillary bodies, hippocampus, perirhinal cortex, and ventricles are also presented. Estimates of visual and verbal recall and item recognition memory were obtained using the Doors and People, the Rey Complex Figure Test, and the Logical Memory subtests of the Wechsler Memory Scales. Each patient's performance was compared to a group of healthy volunteers matched for demographic characteristics, premorbid IQ, and current levels of functioning. A striking double dissociation was evident in material-specific long-term memory, with OG showing significant impairments in visual memory but not verbal memory, and SM showing the opposite profile of preserved visual memory and significantly impaired verbal memory. These impairments affected both recall and item recognition. The reported double dissociation provides the strongest evidence yet that material-specific lateralization of long-term memory also extends to the anteromedial thalamus. The findings are also discussed in relation to proposals that distinct anatomical regions within the medial temporal lobe, anteromedial thalamus, and associated tracts make qualitatively different contributions to recall and item recognition. PMID:22257705

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

    Se-Woong Park

    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.

  13. Monosynaptic connections made by the sensory neurons of the gill- and siphon-withdrawal reflex in Aplysia participate in the storage of long-term memory for sensitization

    Frost, William N.; Castellucci, Vincent F.; Hawkins, Robert D.; Kandel, Eric R.

    1985-01-01

    We have found that in the gill- and siphon- withdrawal reflex of Aplysia, the memory for short-term sensitization grades smoothly into long-term memory with increased amounts of sensitization training. One cellular locus for the storage of the memory underlying short-term sensitization is the set of monosynaptic connections between the siphon sensory cells and the gill and siphon motor neurons. We have now also found that these same monosynaptic connections participate in the storage of the m...

  14. 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)

  15. 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.

  16. Groundwater sampling in Olkiluoto, Eurajoki from drillhole OL-KR6 during a long-term pumping test in 2007

    A long-term pumping test in drillhole OL-KR6 in Olkiluoto was initiated in 2001. Flow and in situ EC measurements as well as groundwater sampling from specific sampling sections have since then been performed yearly. The aim of the study was to obtain information on potential connections via fractures both to the sea and to deep saline groundwater during long-term pumping of the open drillhole. In 2007, four groundwater samples were collected at four different sampling depths (98.5-100.5 m, 125-130 m, 135-137 m and 422-425 m). The groundwater samples were taken in stages using PAVE equipment. The water types found in the groundwater samples from OL-KR6 were Na-Ca-Cl (for samples taken at depths of 98.5-100.5 m and 125-130 m) and Na-Cl (for samples taken at depths of 135-137 m and 422-425 m). The sample taken at depth 422-425 m was saline (TDS> 10000 mg/l), while the other samples were brackish (1000 mg 2O after the air correction had been made. The dominant gas in the groundwater samples was nitrogen. Carbon dioxide was the second dominant gas, except in sample OL-KR6/422-425 m, in which methane, instead, was the second dominant gas. All the samples also contained helium, ethane and argon. Small amounts of ethene, acetylene and propane were found in some samples. No hydrogen or propene was detected in the samples. The dissolved gas concentrations were higher in the OL-KR6 samples in 2006 than in the two previous years. In 2007, the dissolved gas concentration was again lower. One conclusion from this and the previous studies is that changes in the three upper sampling points were most remarkable in 2001-2002 just after pumping started. Otherwise, water compositions were invariable. (orig.)

  17. Understanding the neurobiological mechanisms of learning and memory: Memory systems of the brain, long term potentiation and synaptic...

    Philippe Leff

    2002-01-01

    Full Text Available El fenómeno de LTP es una forma de plasticidad sináptica ampliamente aceptado como un modelo de estabilización de sinapsis en procesos neurobiológicos como el desarrollo del SNC y el fenómeno de aprendizaje y memoria. Desde su descubrimiento por Bliss y Lomo (1973, el fenómeno de potenciación a largo plazo (PLP o LTP (Long-Term Potentiation, por sus siglas en inglés ha sido definido convencionalmente como la estimulación aferente de alta frecuencia que es capaz de despolarizar la célula postsináptica, a través de la activación de receptores glutamaérgicos, con la resultante entrada de calcio a la neurona postsináptica. Este evento neurobiológico produce un incremento intracelular en la concentración de calcio [(Cai] que induce la activación de diferentes sistemas moleculares de señalamiento intracelular (AMPc, proteínas cinasas, fosforilación de proteínas intracelulares que conlleva a una alteración de la actividad postsináptica y/o presináptica, dando por resultado un persistente incremento de respuesta sináptica específica dependiente de la activación del receptor glutamaérgico NMDA...

  18. Long-term effectiveness of CBT for anxiety disorders in an adult outpatient clinic sample: a follow-up study.

    DiMauro, Jennifer; Domingues, Janine; Fernandez, Geraldine; Tolin, David F

    2013-02-01

    The short-term efficacy and effectiveness of Cognitive-Behavioral Therapy (CBT) for treating anxiety disorders in adults has been well established by a multitude of clinical studies and well-controlled randomized trials. However, though the long-term efficacy of CBT as a treatment modality is fairly well established, the degree of its long-term effectiveness has yet to be fully evaluated. Thus, the present study sought to assess both the immediate and long-term effectiveness of individually-administered CBT for the treatment of anxiety disorders in an outpatient psychological clinic. Individuals with a primary diagnosis of Panic Disorder, Social Phobia, Posttraumatic Stress Disorder, Generalized Anxiety Disorder, or Obsessive-Compulsive Disorder who had received 3 or more sessions of CBT were assessed for symptom severity and improvement prior to initiating treatment, at posttreatment, and at one-year follow-up. Symptom severity and improvement ratings were used to categorize patients as "responders" or "remitters" at posttreatment, and "maintained responders" or "maintained remitters" at follow-up. Findings demonstrated that posttreatment success as responder and remitter was significantly maintained at one-year follow-up. Additionally, pre- and posttreatment severity and posttreatment improvement scores were also predictive of maintenance. Furthermore, effect sizes were used to compare the effectiveness of CBT in the present clinical sample to research treatment outcomes demonstrated by previous efficacy studies. PMID:23262115

  19. 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.

  20. Long-term storage of salivary cortisol samples at room temperature

    Chen, Yu-Ming; Cintron, Nitza M.; Whitson, Peggy A.

    1992-01-01

    Collection of saliva samples for the measurement of cortisol during space flights provides a simple technique for studying changes in adrenal function due microgravity. In the present work, several methods for preserving saliva cortisol at room temperature were investigated using radioimmunoassays for determining cortisol in saliva samples collected on a saliva-collection device called Salivettes. It was found that a pretreatment of Salivettes with citric acid resulted in preserving more than 85 percent of the salivary cortisol for as long as six weeks. The results correlated well with those for a sample stored in a freezer on an untreated Salivette.

  1. 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 the cerebral ventricles, but final size critically determines whether lasting locomotor, learning, and memory impairments occur. PMID:24594360

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

    Ellmore, Timothy M.; Feng, Anna; Ng, Kenneth; Dewan, Luthfunnahar; Root, James C.

    2016-01-01

    There is accumulating evidence that sleep as well as awake offline processing is important for the transformation of new experiences into long-term memory (LTM). 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 LTM consolidation. After presentation of multiple naturalistic scenes within a working memory paradigm, recognition was assessed 30 min and 24 h 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 min after exposure to the scenes. Another group of subjects remained in the testing room during the 30 min after scene exposure and engaged in no goal- or task-directed activities. A third group of subjects left the testing room and returned 30 min later. A signal detection analysis revealed no significant differences among the three groups in hits, false alarms, or sensitivity on the 30-min recognition task. At the 24-h recognition test, the group that performed the R-ANT made significantly fewer hits compared to the group that left the testing room and did not perform the attention ask. The group that performed the R-ANT and the group that remained in the testing room during the 30-min post-exposure interval made significantly fewer false alarms on the 24-h 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 best ability to distinguish old from novel visual stimuli after 24 h. These findings suggest that changes in attentional demands and context during an immediate post-exposure offline processing interval modulate visual memory consolidation in a subtle but significant manner. PMID:26779056

  3. 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…

  4. Evidence for large long-term memory capacities in baboons and pigeons and its implications for learning and the evolution of cognition

    Fagot, Joël; Cook, Robert G.

    2006-01-01

    Previous research has shown that birds and primates have a rich repertoire of behavioral and cognitive skills, but the mechanisms underlying these abilities are not well understood. A common hypothesis is that these adaptations are mediated by an efficient long-term memory, allowing animals to remember specific external events and associate appropriate behaviors to these events. Because earlier studies have not sufficiently challenged memory capacity in animals, our comparative research exami...

  5. 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…

  6. 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…

  7. Naringin Enhances CaMKII Activity and Improves Long-Term Memory in a Mouse Model of Alzheimer’s Disease

    Lian-Feng Zhang

    2013-03-01

    Full Text Available The Amyloid-? (A?-induced impairment of hippocampal synaptic plasticity is an underlying mechanism of memory loss in the early stages of Alzheimer's disease (AD in human and mouse models. The inhibition of the calcium/calmodulin-dependent protein kinase II (CaMKII autophosphorylation plays an important role in long-term memory. In this study, we isolated naringin from Pomelo peel (a Citrus species and studied its effect on long-term memory in the APPswe/PS1dE9 transgenic mouse model of AD. Three-month-old APPswe/PS1dE9 transgenic mice were randomly assigned to a vehicle group, two naringin (either 50 or 100 mg/kg body weight/day groups, or an Aricept (2 mg/kg body weight/day group. After 16 weeks of treatment, we observed that treatment with naringin (100 mg/kg body weight/day enhanced the autophosphorylation of CaMKII, increased the phosphorylation of the ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA receptor at a CaMKII-dependent site and improved long-term learning and memory ability. These findings suggest that the increase in CaMKII activity may be one of the mechanisms by which naringin improves long-term cognitive function in the APPswe/PS1dE9 transgenic mouse model of AD.

  8. 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…

  9. Analyses of metallic first mirror samples after long term plasma exposure in Tore Supra

    Lipa, M. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint-Paul-Lez-Durance (France)]. E-mail: manfred.lipa@cea.fr; Schunke, B. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint-Paul-Lez-Durance (France); Gil, Ch. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint-Paul-Lez-Durance (France); Bucalossi, J. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint-Paul-Lez-Durance (France); Voitsenya, V.S. [Institute of Plasma Physics, NSC KIPT, Akademichna St. 1, 61108 Kharkov (Ukraine); Konovalov, V. [Institute of Plasma Physics, NSC KIPT, Akademichna St. 1, 61108 Kharkov (Ukraine); Vukolov, K. [NFI RRC Kurchatov Institute, Moscow (Russian Federation); Balden, M. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany); De Temmerman, G. [Institut fuer Physik, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Oelhafen, P. [Institut fuer Physik, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Litnovsky, A. [Institut fuer Plasmaphysik, Forschungszentrum Juelich, D-42425 Juelich (Germany); Wienhold, P. [Institut fuer Plasmaphysik, Forschungszentrum Juelich, D-42425 Juelich (Germany)

    2006-02-15

    Metallic mirrors are foreseen in ITER diagnostic systems as optical elements directly viewing the plasma radiation. In the frame of an EFDA contract, metallic mirror samples have been exposed for long pulse plasma discharges in Tore Supra (TS) in order to investigate surface modifications caused by erosion and re-deposition processes. Three different materials have been selected: mono-crystalline molybdenum (mc-Mo), polycrystalline stainless steel (SS) and copper (Cu). The mc-Mo samples showed after TS exposure almost no surface roughness modifications and the lowest net-erosion. A slight reflectivity reduction, most pronounced in the near UV, is attributed to light absorption in a thin carbon deposit. Cu mirrors showed by far the highest surface roughness, erosion and diffusive reflectivity. Comparative laboratory glow discharge experiments with virgin reference samples and numerical simulations of erosion/deposition confirm the dominant contribution of conditioning procedures to erosion of mirrors exposed (without shutter protection) in Tore Supra.

  10. Analyses of metallic first mirror samples after long term plasma exposure in Tore Supra

    Lipa, M.; Schunke, B.; Gil, Ch.; Bucalossi, J. [Association Euratom-CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Voitsenya, V.S.; Konovalov, V. [Institut of Plasma Physics, NSC KIPT (Ukraine); Vukolov, K. [Kurchatov Institute, NFI RRC, Moscow (Russian Federation); Balden, M. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Temmerman, G. de; Oelhafen, P. [Basel Univ. (Switzerland). Inst. fuer Physik; Litnovsky, A.; Wienhold, P. [Institut fuer Plasmaphysik, Forschungszentrum Julich (Germany)

    2005-07-01

    Metallic mirrors are foreseen in ITER diagnostic systems as optical elements directly viewing the plasma radiation. In the frame of an EFDA contract, metallic mirror samples have been exposed for long pulse plasma discharges in Tore Supra (TS) in order to investigate surface modifications caused by erosion and re-deposition processes. Three different materials have been selected: mono-crystalline molybdenum (mc-Mo), polycrystalline stainless steel (SS) and copper (Cu). The mc-Mo samples showed after TS exposure almost no surface roughness modifications and the lowest net-erosion. A slight reflectivity reduction, most pronounced in the near UV, is attributed to light absorption in a thin carbon deposit. Cu mirrors showed by far the highest surface roughness, erosion and diffusive reflectivity. Comparative laboratory glow discharge experiments with virgin reference samples and numerical simulations of erosion/deposition confirm the dominant contribution of conditioning procedures to erosion of mirrors exposed (without shutter protection) in Tore Supra. (authors)

  11. Analyses of metallic first mirror samples after long term plasma exposure in Tore Supra

    Metallic mirrors are foreseen in ITER diagnostic systems as optical elements directly viewing the plasma radiation. In the frame of an EFDA contract, metallic mirror samples have been exposed for long pulse plasma discharges in Tore Supra (TS) in order to investigate surface modifications caused by erosion and re-deposition processes. Three different materials have been selected: mono-crystalline molybdenum (mc-Mo), polycrystalline stainless steel (SS) and copper (Cu). The mc-Mo samples showed after TS exposure almost no surface roughness modifications and the lowest net-erosion. A slight reflectivity reduction, most pronounced in the near UV, is attributed to light absorption in a thin carbon deposit. Cu mirrors showed by far the highest surface roughness, erosion and diffusive reflectivity. Comparative laboratory glow discharge experiments with virgin reference samples and numerical simulations of erosion/deposition confirm the dominant contribution of conditioning procedures to erosion of mirrors exposed (without shutter protection) in Tore Supra. (authors)

  12. Long-Term Hydrologic Monitoring Program Sampling and Analysis Results for 2011

    None

    2011-12-21

    The U.S. Department of Energy (DOE) Office of Legacy Management conducted annual sampling at the Rio Blanco site for the LTHMP on May 16 and 17, 2011. The samples were shipped to the U.S. Environmental Protection Agency (EPA) Radiation&Indoor Environments National Laboratory in Las Vegas, Nevada, for analysis. All requested analyses were successfully completed, with the exception of the determination of tritium concentration by the enrichment method, because the laboratory no longer provides that service. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry and tritium using the conventional method. Starting in 2012, DOE will retain a different laboratory that provides the enriched tritium analysis service.

  13. An evaluation of long-term preservation methods for brown bear (Ursus arctos) faecal DNA samples

    Murphy, M.A.; Waits, L.P.; Kendall, K.C.; Wasser, S.K.; Higbee, J.A.; Bogden, R.

    2002-01-01

    Relatively few large-scale faecal DNA studies have been initiated due to difficulties in amplifying low quality and quantity DNA template. To improve brown bear faecal DNA PCR amplification success rates and to determine post collection sample longevity, five preservation methods were evaluated: 90% ethanol, DETs buffer, silica-dried, oven-dried stored at room temperature, and oven-dried stored at -20??C. Preservation effectiveness was evaluated for 50 faecal samples by PCR amplification of a mitochondrial DNA (mtDNA) locus (???146 bp) and a nuclear DNA (nDNA) locus (???200 bp) at time points of one week, one month, three months and six months. Preservation method and storage time significantly impacted mtDNA and nDNA amplification success rates. For mtDNA, all preservation methods had ??? 75% success at one week, but storage time had a significant impact on the effectiveness of the silica preservation method. Ethanol preserved samples had the highest success rates for both mtDNA (86.5%) and nDNA (84%). Nuclear DNA amplification success rates ranged from 26-88%, and storage time had a significant impact on all methods but ethanol. Preservation method and storage time should be important considerations for researchers planning projects utilizing faecal DNA. We recommend preservation of faecal samples in 90% ethanol when feasible, although when collecting in remote field conditions or for both DNA and hormone assays a dry collection method may be advantageous.

  14. 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.

  15. A long-term sampling study of copepods across a tropical creek in Mombasa, Kenya.

    OKemwa, E.N.

    1992-01-01

    Surface copepod samples were taken across Port Kilindini (Likoni Ferry), Mombasa (Kenya), during April, June, August, October, December 1985 and February 1986, including six 24-h series, and analysed for relative abundance. Changes were observed among abundant species of copepods, namely Corycaeus, Acrocalanus, Oithona, Acartia, Oncaea, Centropages, and Temora spp., and Macrosetella gracilis. A regular, predictable cycle caused by the springneap tidal and high-low tidal cycle was revealed. Th...

  16. Accessing SAFOD data products: Downhole measurements, physical samples and long-term monitoring

    Weiland, C.; Zoback, M.; Hickman, S. H.; Ellsworth, W. L.

    2005-12-01

    Many different types of data were collected during SAFOD Phases 1 and 2 (2004-2005) as part of the National Science Foundation's EarthScope program as well as from the SAFOD Pilot Hole, drilled in 2002 and funded by the International Continental Drilling Program (ICDP). Both SAFOD and the SAFOD Pilot Hole are being conducted as a close collaboration between NSF, the U.S. Geological Survey and the ICDP. SAFOD data products include cuttings, core and fluid samples; borehole geophysical measurements; and strain, tilt, and seismic recordings from the multilevel SAFOD borehole monitoring instruments. As with all elements of EarthScope, these data (and samples) are openly available to members of the scientific and educational communities. This paper presents the acquisition, storage and distribution plan for SAFOD data products. Washed and unwashed drill cuttings and mud samples were collected during Phases 1 and 2, along with three spot cores at depths of 1.5, 2.5, and 3.1 km. A total of 52 side-wall cores were also collected in the open-hole interval between 2.5 and 3.1 km depth. The primary coring effort will occur during Phase 3 (2007), when we will continuously core up to four, 250-m-long multilaterals directly within and adjacent to the San Andreas Fault Zone. Drill cuttings, core, and fluid samples from all three Phases of SAFOD drilling are being curated under carefully controlled conditions at the Integrated Ocean Drilling Program (IODP) Gulf Coast Repository in College Station, Texas. Photos of all physical samples and a downloadable sample request form are available on the ICDP website (http://www.icdp-online.de/sites/sanandreas/index/index.html). A suite of downhole geophysical measurements was conducted during the first two Phases of SAFOD drilling, as well as during drilling of the SAFOD Pilot Hole. These data include density, resistivity, porosity, seismic and borehole image logs and are also available via the ICDP website. The SAFOD monitoring program includes fiber-optic strain, tilt, seismic and fluid-pressure recording instruments. Seismic data from the Pilot Hole array are now available in SEED format from the Northern California Earthquake Data Center (http://quake.geo.berkeley.edu/safod/). The strain and tilt instruments are still undergoing testing and quality assurance, and these data will be available through the same web site as soon as possible. Lastly, two terabytes of unprocessed (SEG-2 format) data from a two-week deployment of an 80-level seismic array during April/May 2005 by Paulsson Geophysical Services, Inc. are now available via the IRIS data center (http://www.iris.edu/data/data.htm). Drilling parameters include real-time descriptions of drill cuttings mineralogy, drilling mud properties, and mechanical data related to the drilling process and are available via the ICDP web site. Current status reports on SAFOD drilling, borehole measurements, sampling, and monitoring instrumentation will continue to be available from the EarthScope web site (http://www.earthscope.org).

  17. Long-term memory-based control of attention in multi-step tasks requires working memory: Evidence from domain-specific interference

    RebeccaMartinaFoerster

    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.

  18. 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…

  19. 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…

  20. Long-term environmental trends: Selection of sampling locations in a reactor-aquatic cooling system

    The study objective was to determine whether environmental radionuclide accumulations were occurring in an aquatic system with a 13-y history of supplying a power plant with reactor-cooling water as well as receiving plant discharge. The aquatic system consisted of the following: (1) a reactor-cooling lake; (2) a secondary lake approximately 8 km downstream; and (3) a small stream that interfaced with the two lakes. Gamma-emitting radionuclides were identified and quantified in samples of benthic sediments obtained from representative areas of the aquatic system. This study demonstrated that in a reactor-aquatic cooling system, the component of the aquatic system most likely to experience radionuclide accumulation will not necessarily be the reactor-cooling lake, but will be that component of the aquatic system whose benthic sediments contain the highest concentrations of organic matter. Further, it was shown that the quantity of oxidizable organic matter present in a sediment is a good predictor or marker for potential sites of radionuclide accumulation (i.e., 60Co and 137Cs)

  1. Differentiating the roles of the hippocampus and perirhinal cortex in processes beyond long-term declarative memory: a double dissociation in dementia.

    Lee, Andy C H; Buckley, Mark J; Gaffan, David; Emery, Tina; Hodges, John R; Graham, Kim S

    2006-05-10

    There is increasing evidence to suggest that the hippocampus and perirhinal cortex may mediate processes beyond long-term declarative memory. We assessed patients with Alzheimer's disease (AD) or semantic dementia (SD) on a visual oddity judgment task that did not place an explicit demand on long-term memory and is known to be sensitive to hippocampal and perirhinal cortex lesions. Importantly, within the medial temporal lobe, AD is associated with predominant hippocampal atrophy, whereas SD patients have greater perirhinal cortex damage. The AD group was selectively impaired in oddity judgment for scenes, whereas the SD patients demonstrated a deficit in face oddity judgment only. This compelling double dissociation supports the idea that the hippocampus and perirhinal cortex may be critical for the processing of scenes and objects, respectively, in the domain of perception or very short-term working memory. PMID:16687511

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

    Kyte, Jon Amund; Trachsel, Sissel; Risberg, Bente; thor Straten, Per; Lislerud, Kari; Gaudernack, Gustav

    2009-01-01

    display unconventional cytotoxicity and specifically kill tumor cells expressing mutated TGFbeta receptor II. Cytokine profiling on the long-term survivors demonstrates high IFN gamma/IL10-ratios, favoring immunity over tolerance, and secretion of multiple chemokines likely to mobilize the innate and......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 in...... long-term survivors after peptide vaccination. There were three main study aims: (1) to characterize the immune response in patients with a possible clinical benefit. (2) To analyze the long-term development of responses and effects of booster vaccination. (3) To investigate whether the Th1/Th2...

  3. 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 ascorbic acid administration to rats for 30 days from onset of diabetes alleviated the negative influence of diabetes on learning and memory. Comparing with other nootropic drugs, vitamins have fewer side effects. Therefore, this regimen may provide a new potential alternative for prevention of the impaired cognitive functions associated with diabetes after confirming by clinical trials.

  4. Forgetting of long-term memory requires activation of NMDA receptors, L-type voltage-dependent Ca2+ channels, and calcineurin

    Sachser, Ricardo Marcelo; Santana, Fabiana; Crestani, Ana Paula; Lunardi, Paula; Pedraza, Lizeth Katherine; Quillfeldt, Jorge Alberto; Hardt, Oliver; de Oliveira Alvares, Lucas

    2016-01-01

    In the past decades, the cellular and molecular mechanisms underlying memory consolidation, reconsolidation, and extinction have been well characterized. However, the neurobiological underpinnings of forgetting processes remain to be elucidated. Here we used behavioral, pharmacological and electrophysiological approaches to explore mechanisms controlling forgetting. We found that post-acquisition chronic inhibition of the N-methyl-D-aspartate receptor (NMDAR), L-type voltage-dependent Ca2+ channel (LVDCC), and protein phosphatase calcineurin (CaN), maintains long-term object location memory that otherwise would have been forgotten. We further show that NMDAR activation is necessary to induce forgetting of object recognition memory. Studying the role of NMDAR activation in the decay of the early phase of long-term potentiation (E-LTP) in the hippocampus, we found that ifenprodil infused 30 min after LTP induction in vivo blocks the decay of CA1-evoked postsynaptic plasticity, suggesting that GluN2B-containing NMDARs activation are critical to promote LTP decay. Taken together, these findings indicate that a well-regulated forgetting process, initiated by Ca2+ influx through LVDCCs and GluN2B-NMDARs followed by CaN activation, controls the maintenance of hippocampal LTP and long-term memories over time. PMID:26947131

  5. Pre-frontal executive committee for perception, working memory, attention, long-term memory, motor control, and thinking: a tutorial review.

    Faw, Bill

    2003-03-01

    As an explicit organizing metaphor, memory aid, and conceptual framework, the prefrontal cortex may be viewed as a five-member 'Executive Committee,' as the prefrontal-control extensions of five sub-and-posterior-cortical systems: (1) the 'Perceiver' (dominant-right-hemisphere ventral-lateral prefrontal cortex--VL/PERC-PFC) is the frontal extension of the ventral perceptual stream (the VL/PERC system) which represents the world and self in object coordinates; (2) the 'Verbalizer' (dominant-left-hemisphere ventral-lateral prefrontal cortex system--VL/VERB-PFC) is the frontal extension of the language stream (the VL/VERB system) which represents the world and self in language coordinates; (3) the 'Motivator' (ventral/medial-orbital pre-frontal cortex--VMO-PFC) is the frontal cortical extension of a subcortical extended-amygdala stream (the VMO system) which represents the world and self in motivational/emotional coordinates; (4) the 'Attender' (dorsal-medial/anterior cingulate--DM/AC-PFC) is the frontal cortical extension of a subcortical extended-hippocampal stream (the DM/AC system) which represents the world and self in spatiotemporal coordinates and directs attention to internal and external events; and (5) the 'Coordinator' (the dorsolateral prefrontal cortex--DL-PFC) is the frontal extension of the dorsal perceptual stream (the DL system) which represents the world and self in body- and eye-coordinates and controls willed action and working memory. This tutorial review examines the interacting roles of these five systems in perception, working memory, attention, long-term memory, motor control, and thinking. PMID:12617864

  6. The influence of Brain-Derived Neurotrophic Factor val66met Polymorphism on the degree of long-term potentiation of human visual evoked potentials predicts memory performance.

    Ian J Kirk

    2012-10-01

    Full Text Available A single nucleotide polymorphism of the human BDNF (Val66Met gene may account for much of the variation in human memory performance. BDNF may influence memory via either a modulation of acute plasticity (i.e. long-term potentiation (LTP, or a chronic influence on developing neural systems. Until recently, the link between BDNF and LTP has been difficult to assess in humans. Here we employ our recently developed human LTP paradigm to assess the effects of BDNF polymorphism on LTP and memory. We show that subjects carrying the Met allele had significantly lower levels of LTP than those homozygous for the Val allele, and performed significantly less well in a test of visual memory. Further, the degree of LTP was significantly correlated with the index of visual memory. Thus, polymorphism in the BDNF gene is associated with differences in the degree of acute neural plasticity (LTP, which predicts differences in human mnemonic ability.

  7. 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…

  8. Inhibition of the interactions between eukaryotic initiation factors 4E and 4G impairs long-term associative memory consolidation but not reconsolidation

    Hoeffer, Charles A; Cowansage, Kiriana K.; Arnold, Elizabeth C.; Banko, Jessica L.; Moerke, Nathan J; Rodriguez, Ricard; Schmidt, Enrico K.; Klosi, Edvin; Chorev, Michael; Richard E. Lloyd; Pierre, Philippe; Wagner, Gerhard; Joseph E. LeDoux; Klann, Eric

    2011-01-01

    Considerable evidence indicates that the general blockade of protein synthesis prevents both the initial consolidation and the postretrieval reconsolidation of long-term memories. These findings come largely from studies of drugs that block ribosomal function, so as to globally interfere with both cap-dependent and -independent forms of translation. Here we show that intra-amygdala microinfusions of 4EGI-1, a small molecule inhibitor of cap-dependent translation that selectively disrupts the ...

  9. Who escapes detection? Quantifying the causes and consequences of sampling biases in a long-term field study.

    Kidd, Lindall R; Sheldon, Ben C; Simmonds, Emily G; Cole, Ella F

    2015-11-01

    Inferences drawn from long-term field studies are vulnerable to biases in observability of different classes of individuals, which may lead to biases in the estimates of selection, or fitness. Population surveys that monitor breeding individuals can introduce such biases by not identifying individuals that fail early in their reproductive attempts. Here, we quantify how the standard protocol for detecting breeding females introduces bias in a long-term population study of the great tit, Parus major. We do so by identifying females whose breeding attempts fail before they would normally be censused and explore whether this early failure can be predicted by a number of intrinsic and extrinsic factors. We investigate the effect of these biases on estimates of reproductive performance and selection. We show that females that go undetected by standard censusing because they fail early in their breeding attempt were less likely to have been previously trapped within our study site and were more likely to breed in poor-quality habitats. Furthermore, we demonstrate that this bias sampling had lead previous studies on this population to overestimate the reproductive performance of unringed females, which are likely to be immigrants to the population. Finally, we show that these biases in detectability influence estimates of selection on a key life-history trait. While these conclusions are specific to this study, we suggest that such effects are likely to be widespread and that more attention should be given to whether or not methods for surveying natural populations introduce systematic bias that will influence conclusions about ecological and evolutionary processes. PMID:26081262

  10. Relevance of synaptic tagging and capture to the persistence of long-term potentiation and everyday spatial memory

    Wang, Szu-Han; Redondo, Roger L.; Morris, Richard G. M.

    2010-01-01

    Memory for inconsequential events fades, unless these happen before or after other novel or surprising events. However, our understanding of the neurobiological mechanisms of novelty-enhanced memory persistence is mainly restricted to aversive or fear-associated memories. We now outline an “everyday appetitive” behavioral model to examine whether and how unrelated novelty facilitates the persistence of spatial memory coupled to parallel electrophysiological studies of the persistence of long-...

  11. 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....

  12. The Less Things Change, the More They Are Different: Contributions of Long-Term Synaptic Plasticity and Homeostasis to Memory

    Schacher, Samuel; Hu, Jiang-Yuan

    2014-01-01

    An important cellular mechanism contributing to the strength and duration of memories is activity-dependent alterations in the strength of synaptic connections within the neural circuit encoding the memory. Reversal of the memory is typically correlated with a reversal of the cellular changes to levels expressed prior to the stimulation. Thus, for…

  13. Maternal Diabetes in Pregnancy: Early and Long-Term Outcomes on the Offspring and the Concept of “Metabolic Memory”

    Kabirou Moutairou; Akadiri Yessoufou

    2011-01-01

    The adverse outcomes on the offspring from maternal diabetes in pregnancy are substantially documented. In this paper, we report main knowledge on impacts of maternal diabetes on early and long-term health of the offspring, with specific comments on maternal obesity. The main adverse outcome on progenies from pregnancy complicated with maternal diabetes appears to be macrosomia, as it is commonly known that intrauterine exposure to hyperglycemia increases the risk and programs the offspring t...

  14. Spatial cognition and memory: a reversible lesion with lidocaine into the anteromedial/posterior parietal cortex (AM/PPC affects differently working and long-term memory on two foraging tasks

    PABLO ESPINA-MARCHANT

    2006-01-01

    Full Text Available Place memory is relevant for exploration and forage behaviour. When food supply is dispersed, a win-shift has advantage over a win-stay strategy. In the Olton Octagonal Maze, the rat follows a win-shift strategy using working memory. However, in the Olton 4x4 version, the rat follows a win-stay strategy, using both working and long-term memories. It has been suggested that the neocortex is required for the resolution of tasks demanding long-term, but not for that demanding working memory alone. The role of anteromedial/posterior parietal cortex (AM/PPC was investigated here, using a reversible lesion induced by intracerebral lidocaine infusion. Long-Evans rats were implanted with guide cannulae into the AM/PPC and trained in an Olton 4x4 maze, counting working and long-term memory errors after a delay. Then, the animals were infused with lidocaine or saline during the delay phase and tested for three days. Another series of animals, treated as before, was tested in an Olton Octagonal Maze and subjected to the same injection schedule. In the Olton 4x4 Maze, lidocaine produced a significant increase in working and long-term memory errors, compared to saline and post-lidocaine conditions. In contrast, in the Olton Octagonal Maze, lidocaine did not induce any effect on working memory errors. Thus, AM/PPC is required when both working with previous information and long-term memories are needed, but not when only working memory is required, as it happens under ethological conditions. Whenever food supply is dispersed, a win-shift strategy is preferable

  15. 2D Thermoluminescence imaging of dielectric surface long term charge memory of plasma surface interaction in DBD discharges

    Ambrico, Paolo F.; Ambrico, Marianna; Schiavulli, Luigi; De Benedictis, Santolo

    2014-07-01

    The charge trapping effect due to the exposure of alumina surfaces to plasma has been studied in a volume dielectric barrier discharge (DBD) in Ar and He noble gases. The long lasting charge trapping of alumina dielectric plates, used as barriers in DBDs, is evidenced by an ex situ thermoluminescence (TL) experiment performed with a standard and a custom two-dimensional (2D)-TL apparatus. The spatial density of trapped surface charges is found to be strongly correlated to the plasma morphology, and the surface spatial memory lasted for several minutes to hours after plasma exposure. In the case of Ar, the plasma channel impact signature on the surface shows a higher equivalent radiation dose with respect to the surface plasma wave and the post-discharge species signature. As a consequence, for the development of discharges, inside the dielectric surface the availability of lower energy trapped electrons is larger in the first region of plasma impact. The reported spatial memory increases the likelihood of the occurrence of plasma filaments in the same position in different runs. In He plasmas, the dielectric barrier shows an almost uniform distribution of trapped charges, meaning that there is no preferred region for the development of the discharge. In all cases a slight asymmetry was shown in the direction of the gas flow. This can be interpreted as being due to the long-living species moving in the direction of the gas flow, corresponding with the TL side experiment on the sample exposed to the plasma afterglow. The maximum values and the integral of the 2D-TL images showed a linear relation with the total charge per ac cycle, corresponding with findings for the TL glow curve. In conclusion, 2D-TL images allow the retrieval of information regarding the plasma surface interaction such as the plasma morphology, trap sites and their activation temperature.

  16. Sustained Dorsal Hippocampal Activity is Not Obligatory for Either the Maintenance or Retrieval of Long-Term Spatial Memory

    Nicola J. Broadbent; Squire, Larry R; Clark, Robert E

    2010-01-01

    Memories are initially stored in a labile state and are subject to modification by a variety of treatments, including disruption of hippocampal function. We infused a sodium channel blocker (or CNQX) to inactivate the rat dorsal hippocampus reversibly for 1 week following training on a task of spatial memory (the water maze). Previous work with conventional lesions has established that the dorsal hippocampus is essential for both the acquisition and expression of memory in this task. The ques...

  17. Zif268/Egr1 gain of function facilitates hippocampal synaptic plasticity and long-term spatial recognition memory

    Penke, Zsuzsa; Morice, Elise; Veyrac, Alexandra; Gros, Alexandra; Chagneau , Carine; LeBlanc, Pascale; Samson, Nathalie; Baumgärtel, Karsten; Mansuy, Isabelle M.; Davis, Sabrina; Laroche, Serge

    2014-01-01

    It is well established that Zif268/Egr1, a member of the Egr family of transcription factors, is critical for the consolidation of several forms of memory; however, it is as yet uncertain whether increasing expression of Zif268 in neurons can facilitate memory formation. Here, we used an inducible transgenic mouse model to specifically induce Zif268 overexpression in forebrain neurons and examined the effect on recognition memory and hippocampal synaptic transmission and plasticity. We found ...

  18. 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.

  19. 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

  20. 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 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. PMID:26681831

  1. Long-term safety of radioactive waste disposal. Radioactive analysis of samples from spent fuel leaching experiments

    In order to assess the long-term performance of spent fuel during direct disposal, high burnup fuel (50 MWd/kg U) has been exposed to non-buffered brine solutions and to deionized water under static anaerobic conditions at 25 C. The leaching behaviour of several radionuclides has been observed over periods of approximately 500 d. Currently used radiometric methods (?-, ?-, ?-spectrometry) were applied to the analysis of sample solutions. Due to its low specific activity, uranium was determined using ICP-mass-spectrometry (ICP-MS) or laser induced fluorescence spectrometry (LFS). In order to determine radionuclide concentrations without interferences a preceeding radiochemical separation by ion-exchange, solvent-extraction or extraction chromatography was necessary in most cases. The Sc-isotopes 134/137, which are present in a high excess over other ?-emitting nuclides, were separated using the inorganic ion exchanger ammonium molybdato phosphate (AMP). This step allowed the subsequent ?-spectrometric determination of Am-241, Ag-110m, Ru-106, Sb-125 and Eu-154/155. Activity concentrations of pure ?-emitters like Sr-90, Tc-99, I-129 and Pu-241 were determined by liquid scintillation counting (LSC) after selective separation using extraction chromatography or solvent extraction. The actinides Am-241, Cm-242/244, Pu-238/239/240 and Np-237 were analysed by ?-spectrometry again after selective separation. The direct analysis of uranium by LFS or ICP-MS was hampered by high salt concentrations. Therefore a separation by extraction chromatography turned out to be necessary, too. The analytical procedures used throughout this work are described in detail. (orig.)

  2. The Effect of Synchronized Forced Running with Chronic Stress on Short, Mid and Long- term Memory in Rats

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

    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), Exe...

  3. Long-term treadmill exercise improves spatial memory of male APPswe/PS1dE9 mice by regulation of BDNF expression and microglia activation

    Xiong, JY; Li, SC; Sun, YX; Zhang, XS; Dong, ZZ; Zhong, P; Sun, XR

    2015-01-01

    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...

  4. 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. PMID:26358745

  5. Long-term alteration of Rousse rock samples for CO2 storage: an experimental and numerical study

    Bachaud, P.; Sissmann, O.; Parra, T.

    2013-12-01

    CO2 injection into the Rousse depleted gas reservoir, located in the south-west of France, started in January 2010 and 50,000 tons of this greenhouse effect gas were ultimately injected until March 2013 (Prinet et al. 2013). CO2 fate in the reservoir represents a problem of primary importance, that have been studied by several complementary research works led in collaboration by Total and IFPEN (e.g. Girard et al. 2013, Chiquet et al. 2013). One of the aspects covered by these studies concerned geochemical reactions between the injected fluid, reservoir water and rock minerals. A long-term CO2-exposure experiment was conducted in pressure vessels, and allowed the ageing of reservoir mini-plugs at in situ temperature and pressure conditions (150°C and 80 bar) during almost 24 months. Solid characterization was led every 2 to 3 months using an X-ray microprobe. Elementary maps were then acquired and converted into mineralogical maps using a statistical analysis based on pixels composition. This method allowed the identification of main minerals and of their evolution with alteration. Solution elementary composition was analyzed every week using an ICP-MS. These compositions were used for speciation calculations using the IFPEN's geochemical code Arxim. Initial reservoir mineralogy is mainly constituted of two types of dolomites. One of which forms the rock matrix, the other fills the main reservoir fractures. Quartz, pyrite and calcite traces, as well as two types of phyllosilicates (a potassic illite and a magnesian mixture of chlorite and mica) were also evidenced thanks to our analytical method. After some months of alteration, mineralogical evolutions were observed at the sample edge. Magnesian carbonates (dolomite and magnesite) seemed to precipitate, while an increase of iron, sodium and sulphur (probably due to anhydrite formation) was detected. The combination of these experimental observations to numeric speciation and minerals Saturation Index (SI) calculations allowed us to propose a reactive pathway. A first phase would consist in a slight dissolution of dolomite, potentially accompanied by ordered-dolomite precipitation. A second phase would lead to formation of magnesite and ordered-dolomite, consuming calcium released by calcite dissolution, magnesium released by dissolution of dolomite and of the chlorite/mica mixture, and CO2, thus demonstrating the mineralization potential of the Rousse reservoir. References Chiquet, P., Thibeau, S., Lescanne, M., and Prinet, C. [2013] Geochemical assessment of the injection of CO2 into Rousse depleted gas reservoir. Part II: geochemical impact of the CO2 injection. Energy Procedia, 1-12. Girard, J., Chiquet, P., Thibeau, S., Lescanne, M., and Prinet, C. [2013] Geochemical assessment of the injection of CO2 into Rousse depleted gas reservoir. Part I: Initial mineralogical and geochemical conditions in the Mano reservoir. Energy Procedia, 1-7. Prinet, C., Monne, J., and Thibeau, S. [2013] Lacq pilot injection test: The history of selecting the reservoir, injecting 50 kt of CO2 with monitoring-modeling verification and on-going long term stability demonstration, publication to the EAGE SES Conference, Pau, France, September 30th to October 4th 2013.

  6. Long-Term Effects of 56Fe Irradiation on Spatial Memory of Mice: Role of Sex and Apolipoprotein E Isoform

    Purpose: To assess whether the effects of cranial 56Fe irradiation on the spatial memory of mice in the water maze are sex and apolipoprotein E (apoE) isoform dependent and whether radiation-induced changes in spatial memory are associated with changes in the dendritic marker microtubule-associated protein 2 (MAP-2) and the presynaptic marker synaptophysin. Methods and Materials: Two-month-old male and female mice expressing human apoE3 or apoE4 received either a 3-Gy dose of cranial 56Fe irradiation (600 MeV/amu) or sham irradiation. Mice were tested in a water maze task 13 months later to assess effects of irradiation on spatial memory retention. After behavioral testing, the brain tissues of these mice were analyzed for synaptophysin and MAP-2 immunoreactivity. Results: After irradiation, spatial memory retention of apoE3 female, but not male, mice was impaired. A general genotype deficit in spatial memory was observed in sham-irradiated apoE4 mice. Strikingly, irradiation prevented this genotype deficit in apoE4 male mice. A similar but nonsignificant trend was observed in apoE4 female mice. Although there was no change in MAP-2 immunoreactivity after irradiation, synaptophysin immunoreactivity was increased in irradiated female mice, independent of genotype. Conclusions: The effects of 56Fe irradiation on the spatial memory retention of mice are critically influenced by sex, and the direction of these effects is influenced by apoE isoform. Although in female mice synaptophysin immunoreactivity provides a sensitive marker for effects of irradiation, it cannot explain the apoE genotype-dependent effects of irradiation on the spatial memory retention of the mice.

  7. 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. PMID:23644160

  8. Long-term disorders of memory in the persons survived acute radiation sickness due to Chernobyl accident

    The study involved two groups of the patients: main group - 52 men survived ARS aged 35-55, controls - 23 healthy men aged 36-55. Auditory and visual memory was studied. The obtained results suggest that the changes in the structure of the anterior portions of the brain which are responsible for obtaining, processing and reproduction of verbal information, namely the cortex of the left temporal and frontal regions with their cortical-subcortical associations, play the leading role in the memory disorders in persons survived ARS

  9. Long term exposure to combination paradigm of environmental enrichment, physical exercise and diet reverses the spatial memory deficits and restores hippocampal neurogenesis in ventral subicular lesioned rats.

    Kapgal, Vijayakumar; Prem, Neethi; Hegde, Preethi; Laxmi, T R; Kutty, Bindu M

    2016-04-01

    Subiculum is an important structure of the hippocampal formation and plays an imperative role in spatial learning and memory functions. We have demonstrated earlier the cognitive impairment following bilateral ventral subicular lesion (VSL) in rats. We found that short term exposure to enriched environment (EE) did not help to reverse the spatial memory deficits in water maze task suggesting the need for an appropriate enriched paradigm towards the recovery of spatial memory. In the present study, the efficacy of long term exposure of VSL rats to combination paradigm of environmental enrichment (EE), physical exercise and 18 C.W. diet (Combination Therapy - CT) in reversing the spatial memory deficits in Morris water maze task has been studied. Ibotenate lesioning of ventral subiculum produced significant impairment of performance in the Morris water maze and reduced the hippocampal neurogenesis in rats. Post lesion exposure to C.T. restored the hippocampal neurogenesis and improved the spatial memory functions in VSL rats. Our study supports the hypothesis that the combination paradigm is critical towards the development of an enhanced behavioral and cognitive experience especially in conditions of CNS insults and the associated cognitive dysfunctions. PMID:26851129

  10. 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…

  11. Activin Plays a Key Role in the Maintenance of Long-Term Memory and Late-LTP

    Ageta, Hiroshi; Ikegami, Shiro; Miura, Masami; Masuda, Masao; Migishima, Rika; Hino, Toshiaki; Takashima, Noriko; Murayama, Akiko; Sugino, Hiromu; Setou, Mitsutoshi; Kida, Satoshi; Yokoyama, Minesuke; Hasegawa, Yoshihisa; Tsuchida, Kunihiro; Aosaki, Toshihiko; Inokuchi, Kaoru

    2010-01-01

    A recent study has revealed that fear memory may be vulnerable following retrieval, and is then reconsolidated in a protein synthesis-dependent manner. However, little is known about the molecular mechanisms of these processes. Activin [beta]A, a member of the TGF-[beta] superfamily, is increased in activated neuronal circuits and regulates…

  12. 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.

    Pereira-Carvalho, Regina; Mendes-Aguiar, Carolina O; Oliveira-Neto, Manoel P; Covas, Cláudia J F; Bertho, Alvaro L; Da-Cruz, Alda M; Gomes-Silva, Adriano

    2013-01-01

    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. PMID:24303052

  13. 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

    Pereira-Carvalho, Regina; Mendes-Aguiar, Carolina O.; Oliveira-Neto, Manoel P.; Covas, Cláudia J. F.; Bertho, Álvaro L.; Da-Cruz, Alda M.; Gomes-Silva, Adriano

    2013-01-01

    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. PMID:24303052

  14. Memories of GAMES: Exploring the Long-Term Impacts of After-School Museum Programming on Girls' Attitudes Towards Science

    Snow, Sarah Elizabeth

    The purpose of this study is to investigate any lasting impacts of the University of Colorado Museum of Natural History's Girls at the Museum Exploring Science (GAMES) Program. Using assessment document analysis, student focus groups, and adult interviews, this study examined whether students' positive associations with science continue after completion of the program and whether the program affects the academic and career choices of past participants. Results from the analysis suggest that GAMES has a generally positive impact on participant attitudes towards science in both the short- and long-term. These results also support existing research in identifying key factors in the success of the program including hands-on activities, exposure to diverse careers and female role models, and the incorporation of authentic objects and experiences. These factors of success can contribute to the evidence base about the role of informal education programs in increasing science participation among women, as well as ways in which schools and universities can collaborate to effectively serve populations that are traditionally underrepresented in the sciences.

  15. 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.

  16. Effects of fresh, aged and cooked garlic extracts on short- and long-term memory in diabetic rats

    Alireza Sarkaki; Saeed Valipour Chehardacheric; Yaghoub Farbood; Seyed Mohammad Taghi Mansouri; Bahareh Naghizadeh; Effat Basirian

    2013-01-01

    Objective: The present study was hypothesized to investigate the beneficial effects of fresh, aged, and cooked garlic extracts on blood glucose and memory of diabetic rats induced by streptozocine (STZ). Material and Methods: Diabetes was induced by an intraperitoneal injection of STZ (60 mg/kg body weight). An oral dose of 1000 mg/kg of each garlic extract was given daily for 4 weeks after diabetes induction. Five days after STZ injection, five groups were formed: Control (intact) rats (C...

  17. Differences in long-term memory stability and AmCREB level between forward and backward conditioned honeybees (Apis mellifera)

    Dorothea Eisenhardt

    2015-01-01

    In classical conditioning a predictive relationship between a neutral stimulus (conditioned stimulus; CS) and a meaningful stimulus (unconditioned stimulus; US) is learned when the CS precedes the US. In backward conditioning the sequence of the stimuli is reversed. In this situation animals might learn that the CS signals the end or the absence of the US. In honeybees 30 min and 24 h following backward conditioning a memory for the excitatory and inhibitory properties of the CS could be retr...

  18. 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.

  19. Long-term cannabidiol treatment prevents the development of social recognition memory deficits in Alzheimer's disease transgenic mice.

    Cheng, David; Spiro, Adena S; Jenner, Andrew M; Garner, Brett; Karl, Tim

    2014-01-01

    Impairments in cognitive ability and widespread pathophysiological changes caused by neurotoxicity, neuroinflammation, oxidative damage, and altered cholesterol homeostasis are associated with Alzheimer's disease (AD). Cannabidiol (CBD) has been shown to reverse cognitive deficits of AD transgenic mice and to exert neuroprotective, anti-oxidative, and anti-inflammatory properties in vitro and in vivo. Here we evaluate the preventative properties of long-term CBD treatment in male A?PPSwe/PS1?E9 (A?PP × PS1) mice, a transgenic model of AD. Control and AD transgenic mice were treated orally from 2.5 months of age with CBD (20 mg/kg) daily for 8 months. Mice were then assessed in the social preference test, elevated plus maze, and fear conditioning paradigms, before cortical and hippocampal tissues were analyzed for amyloid load, oxidative damage, cholesterol, phytosterols, and inflammation. We found that A?PP × PS1 mice developed a social recognition deficit, which was prevented by CBD treatment. CBD had no impact on anxiety or associative learning. The prevention of the social recognition deficit was not associated with any changes in amyloid load or oxidative damage. However, the study revealed a subtle impact of CBD on neuroinflammation, cholesterol, and dietary phytosterol retention, which deserves further investigation. This study is the first to demonstrate CBD's ability to prevent the development of a social recognition deficit in AD transgenic mice. Our findings provide the first evidence that CBD may have potential as a preventative treatment for AD with a particular relevance for symptoms of social withdrawal and facial recognition. PMID:25024347

  20. A reversal of the temporal gradient for famous person knowledge in semantic dementia: implications for the neural organisation of long-term memory.

    Hodges, J R; Graham, K S

    1998-08-01

    On tests of autobiographical memory, patients with semantic dementia demonstrate significantly better retrieval of episodic events from the recent past compared with the distant past. This reversal of the Ribot effect has been attributed to the relative sparing of the hippocampal complex in the disorder. Current computational models of long-term memory predict a similar time-dependent pattern of impairment on tests of remote semantic memory. Five patients with semantic dementia were tested on recognition (familiarity) and identification (knowledge) of famous names selected from four different time-periods: 1950's, 1980's, 1990-1993 (early 1990's) and 19941996 (current). As expected, it was found that one patient DM (who had focal left temporal lobe atrophy) showed no significant impairment on recognition of famous names, but was significantly better at producing information about people who were currently famous compared to people famous in the other three time-periods. The other four patients (who had bilateral temporal lobe damage) showed better recognition of famous names from the current time-period (and to a lesser extent the 1950's), yet were profoundly impaired on the identification component, producing very little information across all four time-periods. The results are discussed with respect to current views of the neural organisation of person-specific and general semantic memory. PMID:9751444

  1. Long-term superelastic cycling at nano-scale in Cu-Al-Ni shape memory alloy micropillars

    San Juan, J., E-mail: jose.sanjuan@ehu.es; Gómez-Cortés, J. F. [Dpto. Física Materia Condensada, Facultad de Ciencia y Tecnología, Univ. del País Vasco UPV/EHU, Apdo. 644, 48080 Bilbao (Spain); López, G. A.; Nó, M. L. [Dpto. Física Aplicada II, Facultad de Ciencia y Tecnología, Univ. del País Vasco UPV/EHU, Apdo. 644, 48080 Bilbao (Spain); Jiao, C. [FEI, Achtseweg Noord 5, 5651 GG Eindhoven (Netherlands)

    2014-01-06

    Superelastic behavior at nano-scale has been studied along cycling in Cu-Al-Ni shape memory alloy micropillars. Arrays of square micropillars were produced by focused ion beam milling, on slides of [001] oriented Cu-Al-Ni single crystals. Superelastic behavior of micropillars, due to the stress-induced martensitic transformation, has been studied by nano-compression tests during thousand cycles, and its evolution has been followed along cycling. Each pillar has undergone more than thousand cycles without any detrimental evolution. Moreover, we demonstrate that after thousand cycles they exhibit a perfectly reproducible and completely recoverable superelastic behavior.

  2. A structural basis for enhancement of long-term associative memory in single dendritic spines regulated by PKC

    Hongpaisan, Jarin; Alkon, Daniel L.

    2007-01-01

    Using both scanning confocal and electron microscopic morphometric measurements, we analyzed single dendritic spines of CA1 pyramidal cells in the hippocampi of water maze-trained rats vs. controls. Two days after completion of all training, we observed a memory-specific increase in the number of mushroom spines—all of which make synaptic contacts—but not in the numbers of filopodia or stubby or thin spines, as quantified with double-blind protocols in both scanning confocal and electron micr...

  3. Enhancement of long-term memory retention and short-term synaptic plasticity in cbl-b null mice

    Tan, Dong Ping; Liu, Qi-Ying; Koshiya, Naohiro; Gu, Hua; Alkon, Daniel

    2006-01-01

    The cbl-b gene is a member of the cbl protooncogene family. It encodes a protein with multiple domains, which can interact with other proteins in a variety of signaling pathways. The functions of cbl family genes in the brain are unknown. In this report, we used genetic, immunohistochemical, behavioral, and electrophysiological approaches to study the role of cbl-b in learning and memory. Cbl-b null mice developed normally and had no abnormalities in their locomotor performance. In spatial le...

  4. Long-term continuous allopregnanolone elevation causes memory decline and hippocampus shrinkage, in female wild-type B6 mice.

    Bengtsson, Sara K S; Johansson, Maja; Bäckström, Torbjörn

    2016-02-01

    Chronic stress in various forms increases the risk for cognitive dysfunction, dementia and Alzheimer's disease. While the pathogenesis behind these findings is unknown, growing evidence suggests that chronic increase in neurosteroid levels, such as allopregnanolone, is part of the mechanism. We treated wild-type C57BL/6J mice with allopregnanolone for 5months, using osmotic pumps. This treatment led to moderately increased levels of allopregnanolone, equivalent to that of mild chronic stress. After an interval of no treatment for 1month, female mice showed impaired learning and memory function in the Morris water maze (MWM) in combination with diminished hippocampus weight and increased cerebellum weight, both correlating to MWM performance. Male mice showed a minor reduction in memory function and no differences in brain structure. We conclude that chronic allopregnanolone elevation can lead to cognitive dysfunction and negative brain alterations. We suggest that allopregnanolone could play a key role in the pathogenesis of stress-induced cognitive disturbances and perhaps dementia. PMID:26497250

  5. Influence of long-term storage in cold hibernation on strain recovery and recovery stress of polyurethane shape memory polymer foam

    Tey, S. J.; Huang, W. M.; Sokolowski, W. M.

    2001-04-01

    In this paper, the effects of long-term storage in compressed cold hibernated elastic memory (CHEM) polyurethane foam, a kind of shape memory polymer, are investigated experimentally. The foams were pre-strained at a high temperature, which was above the glass transition temperature, to 80% and 93.4%, respectively, and then cooled back to room temperature. After various periods of cold hibernation (up to two months), they were heated up at fixed length or against different constant loads. It is found that: (1) the maximum stress that the foam could exert at fixed length depends heavily on the amount of pre-strain; (2) expansion rates of 380 and 1273% from the hibernated size against a 1 N load (pre-strained by 80 and 93.4%, respectively) are achievable. However, upon further increases in load, the expansion is reduced dramatically. It appears that the tested CHEM polyurethane foam retains its shape memory properties even after being stored in a compacted state for a long period. Complete strain recovery is attainable for a hibernation period of up to two months.

  6. 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.

  7. 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.

  8. Dilution as a Model of Long-Term Forgetting

    Lansdale, Mark; Baguley, Thom

    2008-01-01

    This article presents a model of long term forgetting based on 3 ideas: (a) Memory for a stimulus can be described by a population of accessible traces; (b) probability of retrieval after a delay is predicted by the proportion of traces in this population that will be defined as correct if sampled; and (c) this population is diluted over time by…

  9. A New Framework for Adaptive Sampling and Analysis During Long-Term Monitoring and Remedial Action Management

    The Argonne team has gathered available data on monitoring wells and measured hydraulic heads from the Argonne 317/319 site and sent it to UIUC. Xiaodong Li, a research assistant supported by the project, has reviewed the data and has fit initial spatiotemporal statistical models to it. Another research assistant, Yonas Demissie, has completed generation of the artificial data that will be used for model development and testing. In order to generate the artificial data a detailed groundwater flow and contaminant transport model was developed based upon characteristics of the 317/319 site. The model covers a multi-year time horizon that includes both before and after planting of the trees. As described in the proposal, the artificial data is created by adding ''measurement'' error to the ''true'' value from the numerical model. To date, only simple white noise error models have been considered. He is now reviewing the literature and beginning to develop a hierarchical modeling approach for the artificial data. Abhishek Singh, a third research assistant supported by the project, is implementing learning models for learning users preferences in an interactive genetic algorithm for solving the inverse problem. Meghna Babbar, the fourth research assistant supported by the project, has been improving the user interface for the interactive genetic algorithm and preparing a long-term monitoring design problem for testing the approach. Gayathri Gopalakrishnan, the last research assistant who is partially supported by the project, has collected substantial data from the 317/319 phytoremediation site at Argonne and has begun learning approaches for modeling these data

  10. Short-term retention of a single word relies on retrieval from long-term memory when both rehearsal and refreshing are disrupted.

    Rose, Nathan S; Buchsbaum, Bradley R; Craik, Fergus I M

    2014-07-01

    Many working memory (WM) models propose that the focus of attention (or primary memory) has a capacity limit of one to four items, and therefore, that performance on WM tasks involves retrieving some items from long-term (or secondary) memory (LTM). In the present study, we present evidence suggesting that recall of even one item on a WM task can involve retrieving it from LTM. The WM task required participants to make a deep (living/nonliving) or shallow ("e"/no "e") level-of-processing (LOP) judgment on one word and to recall the word after a 10-s delay on each trial. During the delay, participants either rehearsed the word or performed an easy or a hard math task. When the to-be-remembered item could be rehearsed, recall was fast and accurate. When it was followed by a math task, recall was slower, error-prone, and benefited from a deeper LOP at encoding, especially for the hard math condition. The authors suggest that a covert-retrieval mechanism may have refreshed the item during easy math, and that the hard math condition shows that even a single item cannot be reliably held in WM during a sufficiently distracting task--therefore, recalling the item involved retrieving it from LTM. Additionally, performance on a final free recall (LTM) test was better for items recalled following math than following rehearsal, suggesting that initial recall following math involved elaborative retrieval from LTM, whereas rehearsal did not. The authors suggest that the extent to which performance on WM tasks involves retrieval from LTM depends on the amounts of disruption to both rehearsal and covert-retrieval/refreshing maintenance mechanisms. PMID:24500778

  11. An Optimal Sampling Design for Observing and Validating Long-Term Leaf Area Index with Temporal Variations in Spatial Heterogeneities

    Yelu Zeng; Jing Li; Qinhuo Liu; Yonghua Qu; Huete, Alfredo R.; Baodong Xu; Geofei Yin; Jing Zhao

    2015-01-01

    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 ...

  12. Long term effects of murine postnatal exposure to decabromodiphenyl ether (BDE-209) on learning and memory are dependent upon APOE polymorphism and age

    Reverte, Ingrid; Klein, Anders Bue; Domingo, José L; Colomina, Maria Teresa

    2014-01-01

    associated with varied vulnerability for the development of neurodegenerative diseases. On postnatal day 10, transgenic mice of both sexes carrying apoE2, apoE3 and apoE4 were orally exposed to 0, 10 or 30mg/kg of BDE-209. Spatial reference memory was assessed in a Morris Water Maze (MWM) task at 4 and 12......months of age. The levels of the brain-derived neurotrophic factor (BDNF) were determined in hippocampus and frontal cortex of mice at 5months of age. Mice carrying different apoE polymorphisms showed differences in the acquisition and retention of the spatial navigation task both at 4 and 12months of...... age. Postnatal exposure to BDE-209 induced long term effects in spatial learning, which were dependent upon age, sex and apoE genotype; these effects were more evident in apoE3 mice. BDNF levels were lower in the frontal cortex of apoE4 mice and higher in the hippocampus of exposed mice, independent...

  13. Identification and Characterization of the V(D)J Recombination Activating Gene 1 in Long-Term Memory of Context Fear Conditioning

    Castro-Pérez, Edgardo; Soto-Soto, Emilio; Pérez-Carambot, Marizabeth; Dionisio-Santos, Dawling; Saied-Santiago, Kristian; Ortiz-Zuazaga, Humberto G.; Peña de Ortiz, Sandra

    2016-01-01

    An increasing body of evidence suggests that mechanisms related to the introduction and repair of DNA double strand breaks (DSBs) may be associated with long-term memory (LTM) processes. Previous studies from our group suggested that factors known to function in DNA recombination/repair machineries, such as DNA ligases, polymerases, and DNA endonucleases, play a role in LTM. Here we report data using C57BL/6 mice showing that the V(D)J recombination-activating gene 1 (RAG1), which encodes a factor that introduces DSBs in immunoglobulin and T-cell receptor genes, is induced in the amygdala, but not in the hippocampus, after context fear conditioning. Amygdalar induction of RAG1 mRNA, measured by real-time PCR, was not observed in context-only or shock-only controls, suggesting that the context fear conditioning response is related to associative learning processes. Furthermore, double immunofluorescence studies demonstrated the neuronal localization of RAG1 protein in amygdalar sections prepared after perfusion and fixation. In functional studies, intra-amygdalar injections of RAG1 gapmer antisense oligonucleotides, given 1?h prior to conditioning, resulted in amygdalar knockdown of RAG1 mRNA and a significant impairment in LTM, tested 24?h after training. Overall, these findings suggest that the V(D)J recombination-activating gene 1, RAG1, may play a role in LTM consolidation. PMID:26843989

  14. Influence of the Melissa officinalis Leaf Extract on Long-Term Memory in Scopolamine Animal Model with Assessment of Mechanism of Action

    Ozarowski, Marcin; Mikolajczak, Przemyslaw L.; Piasecka, Anna; Kachlicki, Piotr; Kujawski, Radoslaw; Bogacz, Anna; Bartkowiak-Wieczorek, Joanna; Szulc, Michal; Kaminska, Ewa; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Gryszczynska, Agnieszka; Opala, Bogna; Lowicki, Zdzislaw; Seremak-Mrozikiewicz, Agnieszka; Czerny, Boguslaw

    2016-01-01

    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.

  15. 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.

  16. A New Framework for Adaptive Sampling and Analysis During Long-Term Monitoring and Remedial Action Management

    Minsker, Barbara; Albert Valocchi; Barbara Bailey

    2008-01-27

    DOE and other Federal agencies are making a significant investment in the development of field analytical techniques, nonintrusive technologies, and sensor technologies that will have a profound impact on the way environmental monitoring is conducted. Monitoring and performance evaluation networks will likely be base on suites of in situ sensors, with physical sampling playing a much more limited role. Designing and using these types of networks effectively will require development of a new paradigm for sampling and analysis of remedial actions, which is the overall goal of this project.

  17. 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) are formed upon multiple-trial conditioning: an early phase (e-LTM) which depends on translation from already available mRNA, and a late phase (l-LTM) which requ...

  18. Long-Term Record of Sampled Disturbances in Northern Eurasian Boreal Forest from Pre-2000 Landsat Data

    Dong Chen

    2014-06-01

    Full Text Available Stand age distribution is an important descriptor of boreal forest structure, which is directly linked to many ecosystem processes including the carbon cycle, the land–atmosphere interaction and ecosystem services, among others. Almost half of the global boreal biome is located in Russia. The vast extent, remote location, and limited accessibility of Russian boreal forests make remote sensing the only feasible approach to characterize these forests to their full extent. A wide variety of satellite observations are currently available to monitor forest change and infer its structure; however, the period of observations is mostly limited to the 2000s era. Reconstruction of wall-to-wall maps of stand age distribution requires merging longer-term site observations of forest cover change available at the Landsat scale at a subset of locations in Russia with the wall-to-wall coverage available from coarse resolution satellites since 2000. This paper presents a dataset consisting of a suite of multi-year forest disturbance samples and samples of undisturbed forests across Russia derived from Landsat Thematic Mapper and Enhanced Thematic Mapper Plus images from 1985 to 2000. These samples provide crucial information regarding disturbance history in selected regions across the Russian boreal forest and are designed to serve as a training and/or validation dataset for coarse resolution data products. The overall accuracy and Kappa coefficient for the entire sample collection was found to be 83.98% and 0.83%, respectively. It is hoped that the presented dataset will benefit subsequent studies on a variety of aspects of the Russian boreal forest, especially in relation to the carbon budget and climate.

  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; Toyama Keiko; Nakanishi Kazuo; Hattori Satoko; Takamura Hironori; Takeda Masatoshi; Miyakawa Tsuyoshi; Hashimoto Ryota

    2008-01-01

    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 be...

  20. Skill-memory consolidation in the striatum: Critical for late but not early long-term memory and stabilized by cocaine

    Willuhn, Ingo; Steiner, Heinz

    2008-01-01

    The sensorimotor striatum is important for procedural learning, including skill learning. Our previous findings indicate that this part of the striatum mediates the acquisition of a motor skill in a running-wheel task and that this skill learning is dependent on striatal D1 dopamine receptors. Here, we investigated whether the sensorimotor striatum is also involved in the consolidation of this skill memory and whether this consolidation is modified by the indirect dopamine receptor agonist co...

  1. 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...

  2. 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.

    2016-04-01

    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 (Γ) 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 (ṁEdd), Γ is anticorrelated with ṁEdd, i.e. `harder-when-brighter' behaviour is observed. The 3 higher-ṁEdd-rate objects show a positive correlation between Γ and ṁEdd. This transition from harder-when-brighter at low ṁEdd~to softer-when-brighter at high ṁEdd~can be explained by a change in the dominant source of seed-photons for X-ray emission from cyclo-synchrotron emission from the Comptonising 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 LINERs 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.

  3. Mid- and long-term effects of family constellation seminars in a general population sample: 8- and 12-month follow-up.

    Hunger, Christina; Weinhold, Jan; Bornhäuser, Annette; Link, Leoni; Schweitzer, Jochen

    2015-06-01

    In a previous randomized controlled trial (RCT), short-term efficacy of family constellation seminars (FCSs) in a general population sample was demonstrated. In this article, we examined mid- and long-term stability of these effects. Participants were 104 adults (M = 47 years; SD = 9; 84% female) who were part of the intervention group in the original RCT (3-day FCS; 64 active participants and 40 observing participants). FCSs were carried out according to manuals. It was predicted that FCSs would improve psychological functioning (Outcome Questionnaire OQ-45.2) at 8- and 12-month follow-up. Additionally, we assessed the effects of FCSs on psychological distress, motivational incongruence, individuals' experience in their personal social systems, and overall goal attainment. Participants yielded significant improvement in psychological functioning (d = 0.41 at 8-month follow-up, p = .000; d = 0.40 at 12-month follow-up, p = .000). Results were confirmed for psychological distress, motivational incongruence, the participants' experience in their personal social systems, and overall goal attainment. No adverse events were reported. This study provides first evidence for the mid- and long-term efficacy of FCSs in a nonclinical population. The implications of the findings are discussed. PMID:25264190

  4. 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; Schønheyder, Henrik Carl; Thomsen, Trine Rolighed

    morphology comparable to the isolates obtained by culturing at the time of sampling. The detection limit for both FISH and PNA-FISH® were >10^3 bacteria/mL. With the eSwab™ system we were able to detect a broad range of bacteria including Staphylococcus spp., Streptococcus spp., Enterococcus spp., and...... Corynebacterium 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...

  5. 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.

  6. Exploration of the short-term and long-term effects of parental illness on children's educational and behavioral functioning using a large Taiwanese sample.

    Chen, Yung-Chi

    2014-05-01

    This study used data from Waves I and II of the Taiwan Educational Panel Survey (TEPS) to explore the potential short-term and long-term effects of parental illness and health condition on children's behavioral and educational functioning. A sample of 11,018 junior high school students and their parents and teachers in Taiwan were included in this present study. The results supported previous work that parental illness may place children at slight risk for poor psychosocial adjustment and behavioral problems. Parental illness was associated with lower adaptive skills and more behavioral problems in children. Children of ill parents showed resilience in their educational functioning in the event of parental illness as children's academic achievement and learning skills were not related to parental illness/health condition. PMID:24203409

  7. 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.

  8. Evaluation of the Quality of Life in Adult Cancer Survivors (QLACS) scale for long-term cancer survivors in a sample of breast cancer survivors

    Avis, Nancy E; Ip, Edward; Foley, Kristie Long

    2006-01-01

    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. PMID:17140438

  9. Long-Term Recency in Anterograde Amnesia

    Talmi, Deborah; Caplan, Jeremy B.; Richards, Brian; Moscovitch, Morris

    2015-01-01

    Amnesia is usually described as an impairment of a long-term memory (LTM) despite an intact short-term memory (STM). The intact recency effect in amnesia had supported this view. Although dual-store models of memory have been challenged by single-store models based on interference theory, this had relatively little influence on our understanding and treatment of amnesia, perhaps because the debate has centred on experiments in the neurologically intact population. Here we tested a key predict...

  10. Long Term Persistence

    Luigi Guiso; Paola Sapienza; Luigi Zingales

    2008-01-01

    Is social capital long lasting? Does it affect long term economic performance? To answer these questions we test Putnam’s conjecture that today marked differences in social capital between the North and South of Italy are due to the culture of independence fostered by the free city states experience in the North of Italy at the turn of the first millennium. We show that the medieval experience of independence has an impact on social capital within the North, even when we instrument for the pr...

  11. Long term morphological modelling

    Kristensen, Sten Esbjørn; Deigaard, Rolf; Taaning, Martin; Fredsøe, Jørgen; Drønen, Nils; Hjelmager Jensen, Jacob

    2010-01-01

    A morphological modelling concept for long term nearshore morphology is proposed and examples of its application are presented and discussed. The model concept combines parameterised representations of the cross-shore morphology, with a 2DH area model for waves, currents and sediment transport in...... the surf zone. Two parameterization schemes are tested for two different morphological phenomena: 1) Shoreline changes due to the presence of coastal structures and 2) alongshore migration of a nearshore nourishment and a bar by-passing a harbour. In the case of the shoreline evolution calculations, a...

  12. Age-related defects in spatial memory are correlated with defects in the late phase of hippocampal long-term potentiation in vitro and are attenuated by drugs that enhance the cAMP signaling pathway

    Bach, Mary Elizabeth; Barad, Mark; Son, Hyeon; Zhuo, Min; Lu, Yun-Fei; Shih, Robert; Mansuy, Isabelle; Hawkins, Robert D.; Kandel, Eric R.

    1999-01-01

    To study the physiological and molecular mechanisms of age-related memory loss, we assessed spatial memory in C57BL/B6 mice from different age cohorts and then measured in vitro the late phase of hippocampal long-term potentiation (L-LTP). Most young mice acquired the spatial task, whereas only a minority of aged mice did. Aged mice not only made significantly more errors but also exhibited greater individual differences. Slices from the hippocampus of aged mice exhibited significantly reduce...

  13. 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...

  14. 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; Metzdorff, Stine Broeng

    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 in...

  15. Long term morphological modelling

    Kristensen, Sten Esbjørn; Deigaard, Rolf; Taaning, Martin; Fredsøe, Jørgen; Drønen, Nils; Hjelmager Jensen, Jacob

    2010-01-01

    concept often used in one-line modelling of cross-shore shifting of an otherwise constant shape cross-shore profile is applied for the case of a groyne and a detached breakwater. In the case of alongshore bar/nourishment migration an alternative parameterization is adopted. All examples are presented......A morphological modelling concept for long term nearshore morphology is proposed and examples of its application are presented and discussed. The model concept combines parameterised representations of the cross-shore morphology, with a 2DH area model for waves, currents and sediment transport in...... the surf zone. Two parameterization schemes are tested for two different morphological phenomena: 1) Shoreline changes due to the presence of coastal structures and 2) alongshore migration of a nearshore nourishment and a bar by-passing a harbour. In the case of the shoreline evolution calculations, a...

  16. Surface analysis of the central and top part of a 1984 JET graphite limiter and of 1984 JET long term samples

    The JET graphite limiter (top and central part) from octant IV as well as long term samples (LTS) and a bellow protection plate all exposed to plasma discharges during the 1984 experimental period have been investigated by means of surface layer analyses techniques. The limiter tiles show characteristic differences in the deposition of metals compared to the 1983 limiter reflecting the higher power loads from the plasma achieved in 1984. Analysis of the LTS reveals a close correlation between erosion sources at the vessel walls of JET and the redeposition areas. This indicates that a major part of the metals eroded at the limiter surface or the wall during normal discharges may not enter the central plasma, but is immediately redeposited close to the area of erosion. Deuterium was found on the sides of the graphite limiter with concentrations exceeding the amount, which could be deposited by simple implantation by at least an order of magnitude. This incidates a codeposition of carbon and deuterium at those areas. (orig.)

  17. Exploitation of FTA cartridges for the sampling, long-term storage, and DNA-based analyses of plant-parasitic nematodes.

    Marek, Martin; Zouhar, Miloslav; Douda, Ondřej; Maňasová, Marie; Ryšánek, Pavel

    2014-03-01

    The use of DNA-based analyses in molecular plant nematology research has dramatically increased over recent decades. Therefore, the development and adaptation of simple, robust, and cost-effective DNA purification procedures are required to address these contemporary challenges. The solid-phase-based approach developed by Flinders Technology Associates (FTA) has been shown to be a powerful technology for the preparation of DNA from different biological materials, including blood, saliva, plant tissues, and various human and plant microbial pathogens. In this work, we demonstrate, for the first time, that this FTA-based technology is a valuable, low-cost, and time-saving approach for the sampling, long-term archiving, and molecular analysis of plant-parasitic nematodes. Despite the complex structure and anatomical organization of the multicellular bodies of nematodes, we report the successful and reliable DNA-based analysis of nematode high-copy and low-copy genes using the FTA technology. This was achieved by applying nematodes to the FTA cards either in the form of a suspension of individuals, as intact or pestle-crushed nematodes, or by the direct mechanical printing of nematode-infested plant tissues. We further demonstrate that the FTA method is also suitable for the so-called "one-nematode-assay", in which the target DNA is typically analyzed from a single individual nematode. More surprisingly, a time-course experiment showed that nematode DNA can be detected specifically in the FTA-captured samples many years after initial sampling occurs. Collectively, our data clearly demonstrate the applicability and the robustness of this FTA-based approach for molecular research and diagnostics concerning phytonematodes; this research includes economically important species such as the stem nematode (Ditylenchus dipsaci), the sugar beet nematode (Heterodera schachtii), and the Northern root-knot nematode (Meloidogyne hapla). PMID:24093923

  18. 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.

  19. Introduction: Long term prediction

    Making a decision upon the right choice of a material appropriate to a given application should be based on taking into account several parameters as follows: cost, standards, regulations, safety, recycling, chemical properties, supplying, transformation, forming, assembly, mechanical and physical properties as well as the behaviour in practical conditions. Data taken from a private communication (J.H.Davidson) are reproduced presenting the life time range of materials from a couple of minutes to half a million hours corresponding to applications from missile technology up to high-temperature nuclear reactors or steam turbines. In the case of deep storage of nuclear waste the time required is completely different from these values since we have to ensure the integrity of the storage system for several thousand years. The vitrified nuclear wastes should be stored in metallic canisters made of iron and carbon steels, stainless steels, copper and copper alloys, nickel alloys or titanium alloys. Some of these materials are passivating metals, i.e. they develop a thin protective film, 2 or 3 nm thick - the so-called passive films. These films prevent general corrosion of the metal in a large range of chemical condition of the environment. In some specific condition, localized corrosion such as the phenomenon of pitting, occurs. Consequently, it is absolutely necessary to determine these chemical condition and their stability in time to understand the behavior of a given material. In other words the corrosion system is constituted by the complex material/surface/medium. For high level nuclear wastes the main features for resolving problem are concerned with: geological disposal; deep storage in clay; waste metallic canister; backfill mixture (clay-gypsum) or concrete; long term behavior; data needed for modelling and for predicting; choice of appropriate solution among several metallic candidates. The analysis of the complex material/surface/medium is of great importance not only in the case of the topics of this workshop but also in other cases because the corrosion resistance of a given material is not an intrinsic property. In case of long term disposal it is essential to have very accurate data for modelling and predicting the behavior of materials engaged for the deep storage of high level nuclear wastes. It is the purpose of this workshop to bring together articles which have a significant contribution to make, and which take into account all the parameters of importance so that appropriate decision can be taken

  20. An essential role for UBE2A/HR6A in learning and memory and mGLUR-dependent long-term depression.

    Bruinsma, Caroline F; Savelberg, Sanne M C; Kool, Martijn J; Jolfaei, Mehrnoush Aghadavoud; Van Woerden, Geeske M; Baarends, Willy M; Elgersma, Ype

    2016-01-01

    UBE2A deficiency syndrome (also known as X-linked intellectual disability type Nascimento) is an intellectual disability syndrome characterized by prominent dysmorphic features, impaired speech and often epilepsy. The syndrome is caused by Xq24 deletions encompassing the UBE2A (HR6A) gene or by intragenic UBE2A mutations. UBE2A encodes an E2 ubiquitin-conjugating enzyme involved in DNA repair and female fertility. A recent study in Drosophila showed that dUBE2A binds to the E3 ligase Parkin, which is required for mitochondrial function and responsible for juvenile Parkinson's disease. In addition, these studies showed impairments in synaptic transmission in dUBE2A mutant flies. However, a causal role of UBE2A in of cognitive deficits has not yet been established. Here, we show that Ube2a knockout mice have a major deficit in spatial learning tasks, whereas other tested phenotypes, including epilepsy and motor coordination, were normal. Results from electrophysiological measurements in the hippocampus showed no deficits in synaptic transmission nor in the ability to induce long-term synaptic potentiation. However, a small but significant deficit was observed in mGLUR-dependent long-term depression, a pathway previously implied in several other mouse models for neurodevelopmental disorders. Our results indicate a causal role of UBE2A in learning and mGLUR-dependent long-term depression, and further indicate that the Ube2a knockout mouse is a good model to study the molecular mechanisms underlying UBE2A deficiency syndrome. PMID:26476408

  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. Mice Overexpressing Type 1 Adenylyl Cyclase Show Enhanced Spatial Memory Flexibility in the Absence of Intact Synaptic Long-Term Depression

    Zhang, Ming; Wang, Hongbing

    2013-01-01

    There is significant interest in understanding the contribution of intracellular signaling and synaptic substrates to memory flexibility, which involves new learning and suppression of obsolete memory. Here, we report that enhancement of Ca[superscript 2+]-stimulated cAMP signaling by overexpressing type 1 adenylyl cyclase (AC1) facilitated…

  3. Petrophysical characterization of first ever drilled core samples from an active CO2 storage site, the German Ketzin Pilot Site - Comparison with long term experiments

    Zemke, Kornelia; Liebscher, Axel

    2014-05-01

    Petrophysical properties like porosity and permeability are key parameters for a safe long-term storage of CO2 but also for the injection operation itself. These parameters may change during and/or after the CO2 injection due to geochemical reactions in the reservoir system that are triggered by the injected CO2. Here we present petrophysical data of first ever drilled cores from a newly drilled well at the active CO2 storage site - the Ketzin pilot site in the Federal State of Brandenburg, Germany. By comparison with pre-injection baseline data from core samples recovered prior to injection, the new samples provide the unique opportunity to evaluate the impact of CO2 on pore size related properties of reservoir and cap rocks at a real injection site under in-situ reservoir conditions. After injection of 61 000 tons CO2, an additional well was drilled and new rock cores were recovered. In total 100 core samples from the reservoir and the overlaying caprock were investigated by NMR relaxation. Permeability of 20 core samples was estimated by nitrogen and porosity by helium pycnometry. The determined data are comparable between pre-injection and post-injection core samples. The lower part of the reservoir sandstone is unaffected by the injected CO2. The upper part of the reservoir sandstone shows consistently slightly lower NMR porosity and permeability values in the post-injection samples when compared to the pre-injection data. This upper sandstone part is above the fluid level and CO2 present as a free gas phase and a possible residual gas saturation of the cores distorted the NMR results. The potash-containing drilling fluid can also influence these results: NMR investigation of twin samples from inner and outer parts of the cores show a reduced fraction of larger pores for the outer core samples together with lower porosities and T2 times. The drill mud penetration depth can be controlled by the added fluorescent tracer. Due to the heterogeneous character of the Stuttgart Formation it is difficult to estimate definite CO2 induced changes from petrophysical measurements. The observed changes are only minor. Several batch experiments on Ketzin samples drilled prior injection confirm the results from investigation of the in-situ rock cores. Core samples of the pre-injection wells were exposed to CO2 and brine in autoclaves over various time periods. Samples were characterized prior to and after the experiments by NMR and Mercury Injection Porosimetry (MIP). The results are consistent with the logging data and show only minor change. Unfortunately, also in these experiments observed mineralogical and petrophysical changes were within the natural heterogeneity of the Ketzin reservoir and precluded unequivocal conclusions. However, given the only minor differences between post-injection well and pre-injection well, it is reasonable to assume that the potential dissolution-precipitation processes appear to have no severe consequences on reservoir and cap rock integrity or on the injection behaviour. This is also in line with the continuously recorded injection operation parameter. These do not point to any changes in reservoir injectivity.|

  4. Methamphetamine-induced short-term increase and long-term decrease in spatial working memory affects Protein Kinase M zeta (PKMζ, dopamine, and glutamate receptors

    Ingrid K Tulloch

    2014-12-01

    Full Text Available Methamphetamine (MA is a toxic, addictive drug shown to modulate learning and memory, yet the neural mechanisms are not fully understood. We investigated the effects of 2 weekly injections of MA (30 mg/kg on working memory using the radial 8-arm maze (RAM across 5 weeks in adolescent-age mice. MA-treated mice show a significant improvement in working memory performance 1 week following the first MA injection compared to saline-injected controls. Following 5 weeks of MA abstinence mice were re-trained on a reference and working memory version of the RAM to assess cognitive flexibility. MA-treated mice show significantly more working memory errors without effects on reference memory performance. The hippocampus and dorsal striatum were assessed for expression of glutamate receptors subunits, GluA2 and GluN2B; dopamine markers, dopamine 1 receptor (D1, dopamine transporter (DAT and tyrosine hydroxylase (TH; and memory markers, protein kinase M zeta (PKMζ and protein kinase C zeta (PKCζ. Within the hippocampus, PKMζ and GluA2 are both significantly reduced after MA supporting the poor memory performance. Additionally, a significant increase in GluN2B and decrease in D1 identifies dysregulated synaptic function. In the striatum, MA treatment increased cytosolic DAT and TH levels associated with dopamine hyperfunction. MA treatment significantly reduced GluN2B while increasing both PKMζ and PKCζ within the striatum. We discuss the potential role of PKMζ/PKCζ in modulating dopamine and glutamate receptors after MA treatment. These results identify potential underlying mechanisms for working memory deficits induced by MA.

  5. Long-term testing

    Ferber, M.; Graves, G. A., Jr.

    Land-based gas turbines are significantly different from automotive gas turbines in that they are designed to operate for 50,000 h or greater (compared to 5,000-10,000 h). The primary goal of this research is to determine the long-term survivability of ceramic materials for industrial gas turbine applications. Research activities in this program focus on the evaluation of the static tensile creep and stress rupture (SR) behavior of three commercially available structural ceramics which have been identified by the gas turbine manufacturers as leading candidates for use in industrial gas turbines. For each material investigated, a minimum of three temperatures and four stresses will be used to establish the stress and temperature sensitivities of the creep and SR behavior. Because existing data for many candidate structural ceramics are limited to testing times less than 2,000 h, this program will focus on extending these data to times on the order of 10,000 h, which represents the lower limit of operating time anticipated for ceramic blades and vanes in gas turbine engines. A secondary goal of the program will be to investigate the possibility of enhancing life prediction estimates by combining interrupted tensile SR tests and tensile dynamic fatigue tests in which tensile strength is measured as a function of stressing rate. The third goal of this program will be to investigate the effects of water vapor upon the SR behavior of the three structural ceramics chosen for the static tensile studies by measuring the flexural strength as a function of stressing rate at three temperatures.

  6. Exercise and Sodium Butyrate Transform a Subthreshold Learning Event into Long-Term Memory via a Brain-Derived Neurotrophic factor-Dependent Mechanism

    Intlekofer, Karlie A; Berchtold, Nicole C.; Malvaez, Melissa; Carlos, Anthony J.; McQuown, Susan C; Cunningham, Michael J; Wood, Marcelo A.; Cotman, Carl W.

    2013-01-01

    We demonstrate that exercise enables hippocampal-dependent learning in conditions that are normally subthreshold for encoding and memory formation, and depends on hippocampal induction of brain-derived neurotrophic factor (BDNF) as a key mechanism. Using a weak training paradigm in an object location memory (OLM) task, we show that sedentary mice are unable to discriminate 24 h later between familiar and novel object locations. In contrast, 3 weeks of prior voluntary exercise e...

  7. Long-term exposure to low frequency electro-magnetic fields of 50- and 217-Hz leads to learning and memory deficits in mice

    Soheila Khodakarim; Mostafa Rezaei-Tavirani; Elaheh Nooshinfar

    2012-01-01

    Electromagnetic field (EMF) radiation affects cellular and brain chemistry and function, resulting in deleterious effects such as free radicals formation, impaired DNA repair, reduced melatonin and blood brain barrier protection, and defects on learning and memory and other higher brain functions. In this paper the effects of low frequency EMF of 50- and 217 Hz, ranges often associated with common electronic devices such as televisions and cell phones were examined on learning and memory in a...

  8. 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.

  9. Development of a Long-term Sampling Network to Monitor Restoration Success in the Southwest Coastal Everglades: Vegetation, Hydrology, and Sediments

    Smith, Thomas J., III

    2004-01-01

    Introduction and History Hurricane Andrew, a Category 5 storm, crossed the southern Florida peninsula on the morning of August 24, 1992 (Fig. 1). Following the storm, the National Park Service conducted an environmental damage assessment to gauge the storm's impacts on the natural resources of south Florida Park Service holdings (Pimm et al., 1994). Although hurricanes have impacted Park Service lands such as the Everglades in the past (Houston and Powell, 2003), no systematic, permanent sampling scheme has been established to monitor long-term recovery (or lack thereof) following disturbance. In October 1992, vegetation monitoring plots were established in heavily damaged areas of mangrove forest on the southwest coast of the Everlgades, along the Lostmans and Broad Rivers (Smith et al., 1994, see Fig. 2). As the permanent plot network was being established, funding was awarded for the South Florida Global Climate Change project (SOFL-GCC). This led to the establishment of a network of hydrological monitoring stations (Anderson and Smith, 2004). Finally, sediment elevation tables (SETs) were installed at many locations. SETs provide the means to measure very small changes (2 mm) in the sediment surface elevation accurately over time (Cahoon et al., 2002). We also set up marker horizons to measure accretion of sediment at each site (Smith and Cahoon, 2003). Sampling sites were located along three transects extending from upstream freshwater wetlands to downstream saltwater wetlands along the Shark, Lostmans and Chatham Rivers in Everglades National Park (Fig. 2). While we were developing our sampling network for basic scientific research needs, concern mounted over the health of the Greater Everglades Ecosystem and in particular over the influence of decreased freshwater flows (Smith et al., 1989). Ecosystem restoration planning was begun, resulting in the multi-agency, $8 billion Comprehensive Everglades Restoration Plan (CERP). Our co-located sampling networks Fig. 3) allow us to track the interaction of hydrology, sediment, and vegetation over time, and will provide the opportunity to monitor the progress of the Everglades restoration and to gauge its success. Our earlier research questions have been modified over time to place a major emphasis on CERP needs, while still recognizing the importance of other processes, including disturbance and sea-level rise. Our research addresses processes relevant to the following restoration and related questions: * How will increasing freshwater flow affect wetland primary production? * Will increasing freshwater inflow alter nutrient availability? * Does recovery following disturbance in mangroves depend on freshwater inflow? * Will the position of vegetation ecotones change in response to upstream water management? * What will be the influence of global climate change, such as sea-level rise, on the Everglades restoration? * Will processes of wetlands soil formation be altered by sea-level rise and changed freshwater inflow?

  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. MHC Class I Immune Proteins Are Critical for Hippocampus-Dependent Memory and Gate NMDAR-Dependent Hippocampal Long-Term Depression

    Nelson, P. Austin; Sage, Jennifer R.; Wood, Suzanne C.; Davenport, Christopher M.; Anagnostaras, Stephan G.; Boulanger, Lisa M.

    2013-01-01

    Memory impairment is a common feature of conditions that involve changes in inflammatory signaling in the brain, including traumatic brain injury, infection, neurodegenerative disorders, and normal aging. However, the causal importance of inflammatory mediators in cognitive impairments in these conditions remains unclear. Here we show that…

  12. 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…

  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. 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…

  15. MHC Class I Immune Proteins Are Critical for Hippocampus-Dependent Memory and Gate NMDAR-Dependent Hippocampal Long-Term Depression

    Nelson, P. Austin; Sage, Jennifer R.; Wood, Suzanne C.; Davenport, Christopher M.; Anagnostaras, Stephan G.; Boulanger, Lisa M.

    2013-01-01

    Memory impairment is a common feature of conditions that involve changes in inflammatory signaling in the brain, including traumatic brain injury, infection, neurodegenerative disorders, and normal aging. However, the causal importance of inflammatory mediators in cognitive impairments in these conditions remains unclear. Here we show that…

  16. The elevated T-maze task as an animal model to simultaneously investigate the effects of drugs on long-term memory and anxiety in mice.

    Asth, Laila; Lobão-Soares, Bruno; André, Eunice; Soares, Vanessa de Paula; Gavioli, Elaine Cristina

    2012-04-10

    The elevated T-maze (ETM) is an apparatus derived from the elevated plus-maze test, which is used to evaluate anxiety. Because anxiety is a biasing factor in models of memory, this study proposed the ETM as a task for the simultaneous assessment of memory and anxiety in mice. The ETM consists of one enclosed and two open arms. The procedure is based on the avoidance of open spaces learned during training session, in which mice were exposed to the enclosed arm as many times as needed to stay 300s. In the test session, memory is assessed by re-exposing the mouse to the enclosed arm and the latency to enter an open arm was recorded. The anxiolytic diazepam (DZP; 1 or 2mg/kg) and the amnestic biperiden (BPR; 0.5, 1 or 3mg/kg) were injected at three distinct times: pre-training, post-training, and pre-test. Pre-training administration of BPR 1 and DZP 2 increased the number of trials needed to reach the avoidance criterion, suggesting a passive avoidance learning impairment. However, BPR induced hyperlocomotion, which could bias the interpretation of any BPR-induced effects during the training session. Pre-training injection of BPR did not affect the spontaneous increase in the latency to enter an open arm between trials, while DZP reduced latencies in the first three trials suggesting anxiolysis. In the test session, pre-training injection of BPR 1 and DZP 2 reduced latencies to enter an open arm, indicating memory impairment. Post-training and pre-test injection of DZP or BPR did not affect memory. In conclusion, the proposed ETM task is practical for the detection of the anxiolytic and amnesic effects of drugs. PMID:22394406

  17. 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 becomes a predictor for the US eliciting a conditioned response (CR). Here we study the role of US duration in classical conditioning by examining honeybees conditio...

  18. Multimodal Assessment of Long-Term Memory Recall and Reinstatement in a Combined Cue and Context Fear Conditioning and Extinction Paradigm in Humans

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

    2013-01-01

    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...

  19. 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.

  20. Accessibility Long Term Perspectives

    Kay Axhausen

    2008-11-01

    Full Text Available Improved accessibility and its correlate lower generalized cost of contact, travel and transport have been sought by dynamic human societies for their economic and social benefits through- out recorded history. The paper will reflect about this process at a number of different spatial and temporal scales based on a conceptual model. Looking back at European history, it will trace the interaction between Christaller's logic of local market areas and the idea of (low contact cost network cities. Focusing on Switzerland since 1950 it will show how network investment changed the relative distribution of population and employment and how this interacted with changes in the preferences of the travelers. Using a recent snapshot of how a substantial sample of Swiss maintain their social networks over often very large areas, it will try to answer the question of what will happen in the future, if the current trend of ever lower costs of contact will persist.

  1. Long-Term Recency in Anterograde Amnesia.

    Talmi, Deborah; Caplan, Jeremy B; Richards, Brian; Moscovitch, Morris

    2015-01-01

    Amnesia is usually described as an impairment of a long-term memory (LTM) despite an intact short-term memory (STM). The intact recency effect in amnesia had supported this view. Although dual-store models of memory have been challenged by single-store models based on interference theory, this had relatively little influence on our understanding and treatment of amnesia, perhaps because the debate has centred on experiments in the neurologically intact population. Here we tested a key prediction of single-store models for free recall in amnesia: that people with amnesia will exhibit a memory advantage for the most recent items even when all items are stored in and retrieved from LTM, an effect called long-term recency. People with amnesia and matched controls studied, and then free-recalled, word lists with a distractor task following each word, including the last (continual distractor task, CDFR). This condition was compared to an Immediate Free Recall (IFR, no distractors) and a Delayed Free Recall (DFR, end-of-list distractor only) condition. People with amnesia demonstrated the full long-term recency pattern: the recency effect was attenuated in DFR and returned in CDFR. The advantage of recency over midlist items in CDFR was comparable to that of controls, confirming a key prediction of single-store models. Memory deficits appeared only after the first word recalled in each list, suggesting the impairment in amnesia may emerge only as the participant's recall sequence develops, perhaps due to increased susceptibility to output interference. Our findings suggest that interference mechanisms are preserved in amnesia despite the overall impairment to LTM, and challenge strict dual-store models of memory and their dominance in explaining amnesia. We discuss the implication of our findings for rehabilitation. PMID:26046770

  2. Medial prefrontal cortex ablation results in impaired spatial memory and hippocampal long-term potentiation with increased functional connectivity in vivo

    Amira Latif-Hernandez

    2015-04-01

    Full Text Available Hippocampus (HC and prefrontal cortex (PFC are two brain regions that are essential for cognitive flexibility, ability to adapt to new situational demands (Hampshire, Chaudhry, Owen, & Roberts, 2012. PFC/HC projections are activated during attention and dissociable types of flexible behavior (Hok V, Lenck-Santini PP, Roux S, Save E, Muller RU, 2007. Furthermore, impaired PFC/HC communications might contribute to the cognitive rigidity observed in a variety of neurodegenerative disorders such as Alzheimer’s and frontotemporal dementia (Ittner & Götz, 2011. In the present study, we investigated the functional role of the PFC/HC network in cognitive flexibility by combining behavioral, electrophysiological, molecular readouts and brain imaging “in vivo” with excitotoxic inactivation (quinolinic acid, 30 mM. C57/BL6J mice were trained in the Morris water maze for ten consecutive days, a hippocampus-dependent spatial learning task. Immediately after acquisition learning, excitotoxic lesions were applied to the PFC (comprising infralimbic -IL/prelimbic –PrL-cortices and cognitive flexibility was assessed during spatial reversal trials for five days. PFC lesions impaired reversal learning and affected search strategies to locate the hidden platform. Lesioned animals used a significantly higher percentage of non-spatial search strategies during reversal learning whereas control mice benefitted significantly more from spatial search strategies. Furthermore, the lesions in the IL/PrL area altered long-term potentiation (LTP in the hippocampal CA1-region of slices prepared ex-vivo immediately after reversal learning. PFC-lesioned mice showed reduced hippocampal LTP and decreased amplitude in the Input/Output curve, as a measure of basal synaptic transmission. We also examined whether the reduced LTP was a consequence of the missing PFC input or rather an acute effect of the excitotoxic hyperactivation of NMDA receptors in the PFC caused by quinolinic acid. Importantly, twenty-four hours after the excitotoxic injection, hippocampal LTP was similar to controls. Moreover, the analysis of synaptic proteins revealed that PSD95, AMPA receptors and the NR2A subunit of the NMDA receptors were not affected in the hippocampi tissue from the lesioned mice compared with sham treated. In addition, resting state magnetic resonance imaging (rsfMRI on day seven after the QA injection into PFC revealed stronger functional connectivity of the CA1 region of the HC with the rest brain areas, which might indicate an hippocampal hyperactivation caused by compensatory mechanisms to counteract the prefrontal impairment. In conclusion, mPFC lesions impair behavioral flexibility that is needed to adjust behavior to new environmental demands and hippocampal synaptic plasticity.

  3. Long-Term Effects of Physical Exercise on Verbal Learning and Memory in Middle-Aged Adults: Results of a One-Year Follow-Up Study

    Brigitte Röder

    2012-08-01

    Full Text Available A few months of physical exercise have been shown to increase cognition and to modulate brain functions in previously sedentary, mainly older adults. However, whether the preservation of newly gained cognitive capacities requires an active maintenance of the achieved fitness level during the intervention is not yet known. The aim of the present study was to test whether cardiovascular fitness one year after an exercise intervention was linked to cognitive variables. Twenty-five healthy participants (42–57 years of age took part in a follow-up assessment one year after the end of a supervised exercise intervention. Measurements included a cardiovascular fitness test, psychometric tests of verbal learning and memory and selective attention as well as questionnaires assessing physical activity and self-efficacy beliefs. Recognition scores of participants with higher cardiovascular fitness at follow-up did not change significantly during the follow-up period; however, the scores of participants with lower cardiovascular fitness decreased. One year after the end of the physical training intervention, previously sedentary participants spent more hours exercising than prior to the intervention. The time participants spent exercising correlated with their self-efficacy beliefs. These results demonstrate a direct link between verbal learning and cardiovascular fitness and show that positive effects of physical interventions on learning and memory do need an active maintenance of cardiovascular fitness.

  4. Long-term effects of physical exercise on verbal learning and memory in middle-aged adults: results of a one-year follow-up study.

    Hötting, Kirsten; Schauenburg, Gesche; Röder, Brigitte

    2012-01-01

    A few months of physical exercise have been shown to increase cognition and to modulate brain functions in previously sedentary, mainly older adults. However, whether the preservation of newly gained cognitive capacities requires an active maintenance of the achieved fitness level during the intervention is not yet known. The aim of the present study was to test whether cardiovascular fitness one year after an exercise intervention was linked to cognitive variables. Twenty-five healthy participants (42-57 years of age) took part in a follow-up assessment one year after the end of a supervised exercise intervention. Measurements included a cardiovascular fitness test, psychometric tests of verbal learning and memory and selective attention as well as questionnaires assessing physical activity and self-efficacy beliefs. Recognition scores of participants with higher cardiovascular fitness at follow-up did not change significantly during the follow-up period; however, the scores of participants with lower cardiovascular fitness decreased. One year after the end of the physical training intervention, previously sedentary participants spent more hours exercising than prior to the intervention. The time participants spent exercising correlated with their self-efficacy beliefs. These results demonstrate a direct link between verbal learning and cardiovascular fitness and show that positive effects of physical interventions on learning and memory do need an active maintenance of cardiovascular fitness. PMID:24961197

  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. Brevican-deficient mice display impaired hippocampal CA1 long-term potentiation but show no obvious deficits in learning and memory

    Brakebusch, Cord; Seidenbecher, Constanze I; Asztely, Fredrik; Rauch, Uwe; Matthies, Henry; Meyer, Hannelore; Krug, Manfred; Böckers, Tobias M; Zhou, Xiaohong; Kreutz, Michael R; Montag, Dirk; Gundelfinger, Eckart D; Fässler, Reinhard

    2002-01-01

    Brevican is a brain-specific proteoglycan which is found in specialized extracellular matrix structures called perineuronal nets. Brevican increases the invasiveness of glioma cells in vivo and has been suggested to play a role in central nervous system fiber tract development. To study the role ....... Detailed behavioral analysis revealed no statistically significant deficits in learning and memory. These data indicate that brevican is not crucial for brain development but has restricted structural and functional roles.......Brevican is a brain-specific proteoglycan which is found in specialized extracellular matrix structures called perineuronal nets. Brevican increases the invasiveness of glioma cells in vivo and has been suggested to play a role in central nervous system fiber tract development. To study the role of...... brevican in the development and function of the brain, we generated mice lacking a functional brevican gene. These mice are viable and fertile and have a normal life span. Brain anatomy was normal, although alterations in the expression of neurocan were detected. Perineuronal nets formed but appeared to be...

  7. Long Term Survivors of Glioblastoma

    Nezih OKTAR

    2009-12-01

    Full Text Available There is no generally accepted definition of long-term GBM survivors (LTGBMS. Usually most authors define long-term GBM survivor as a patient who survives at least 3 years after the histological diagnosis of glioblastoma. LTGBMS are uncommon and are reported to occur in 0.5%-16% of cases. In our ENOK (Ege Neuro-Oncology Council cases we have 12 out of 372 GBM patients who survived more than 3 years (3.2%. The clinical and molecular factors that contribute to long-term survival are still unknown. Authors underline the association of glioblastoma long-term survival with prognostically favorable clinical factors, in particular young age and good initial performance score (KPS as well as MGMT promotor hypermethylation.

  8. Memória de longo prazo modulada pela memória de curto prazo / Long term memory modulated by short term memory / Memoria a largo plazo modulada por la memoria a corto plazo

    Viviane, Moreira-Aguiar; Allan Pablo, Lameira; Erick Quintas, Conde; Antônio, Pereira Júnior; Carlo Arrigo, Umiltà; Luiz de Gonzaga, Gawryszewski.

    Full Text Available Quando um estímulo ocorre aleatoriamente à esquerda ou à direita, a resposta é mais rápida quando estímulo e resposta estão no mesmo lado (condição compatível) do que em lados opostos (condição incompatível). Na tarefa de Simon, embora a resposta seja selecionada pela forma (ou cor) do estímulo, a p [...] osição deste influencia o Tempo de Reação Manual (TRM). O efeito Simon corresponde à diferença entre as médias dos TRMs nas duas condições (incompatível e compatível). Neste trabalho, estudamos como uma tarefa prévia de compatibilidade realizada com um dedo indicador modula o efeito Simon. Vinte e oito voluntários realizaram uma tarefa de compatibilidade seguida pela tarefa de Simon. No grupo compatível (14 voluntários), encontramos um efeito Simon de 24 ms. No incompatível (14 voluntários), ocorreu um efeito Simon inverso de -16 ms. Estes resultados mostram uma modulação da memória de longo prazo por uma tarefa envolvendo a memória de curto prazo. Abstract in spanish Cuando un estimulo ocurre aleatoriamente a la izquierda o a la derecha, la respuesta es más rápida cuando el estimulo y la respuesta están del mismo lado (condición compatible), de que cuando están en lados opuestos (condición incompatible). En la prueba de Simon, el color o la forma del estímulo de [...] termina la respuesta, pero éste es más rápido cuando hay una correlación espacial entre el estímulo y la respuesta. En este trabajo, estudiamos la modulación del efecto Simon por la tarea de la compatibilidad espacial en la cual uno dedo índice respondió. Veintiocho voluntarios realizaron la prueba de compatibilidad (14 la compatible y 14 la incompatible). Después el voluntario realizó la prueba de Simon. En el grupo compatible, encontramos efecto de Simon de 21 ms. Sin embargo, en el grupo incompatibles, ocurrió un efecto de Simon inverso de -16 ms. Estos resultados demuestran una modulación de la memoria a largo plazo por la memoria a corto plazo. Abstract in english When a stimulus randomly occurs at left or right, the response is faster when stimulus and response are on the same side (compatible condition) than on opposite sides (incompatible condition). In the Simon task, color or shape determines the correct response but it is faster when there is correspond [...] ence between stimulus and response key positions. In this research, we studied the Simon effect modulation through a previous spatial compatibility task in which just one index finger presses the keys. Twenty-eight volunteers run compatibility tasks (14 compatible and 14 incompatible). Then, they performed a Simon task in which the correct response was selected by shape. A Simon effect of 24 ms was found in the compatible group. An inverse Simon effect of -16 ms occurred in the incompatible group. These results show long-term memory modulation by task involving short-term memory.

  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 of TregCM was inversely correlated with the viral load (r=−0.51; p=0.016. Conclusions: In our aviremic long-term cART-treated and viremic untreated patients, the total Treg cell population seems to be unaffected by HIV infection. However, our results showed that the analysis of the naïve and memory-like Treg subsets may provide a better understanding of the real contribution of Tregs in HIV disease and therapy.

  10. 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

  11. Long-term interim storage

    Spent fuel and high and intermediate level nuclear waste produced and being produced, are currently stored in facilities whose design lifetime is in the order of fifty years. Life extension through storage facility upgrades is one possible way of achieving long-term interim storage. One alternative consists in the implementation of storage solutions, purposely designed and built to meet long term goals: packages are safely secured and preserved, loading and retrieval of packages can be achieved under safe and economically viable conditions over the long time scale envisaged (100 to 300 years). Research carried out to address the third R and D requirement put in the December 1991 law specifically deals with the latter option. Two arrangements (above and near-surface configurations) of the long-term storage facilities were studied for each package type (long-lived intermediate level waste and high level waste). The use of design specifications stricter than those usually selected for the construction of conventional structures, combined with a maintenance program, make it possible to design facilities with a life time of a few centuries. At the same time, container demonstrators were made for the different categories of long-lived intermediate level waste and for thermal packages, high level waste and spent fuel. Considering all these elements, it appears that long-term interim storage is a waste management solution, technically feasible, that can be decided upon and implemented, but cannot last for ever. (authors)

  12. Long-term animal studies on the effect of incorporated radioactive and nonradioactive particles and their synergism - radiochemical preparation of tissue samples and alphaspectroscopy

    It was the objective of this study to develop methods for the radiochemical preparation of samples along with physical measuring and evaluating techniques for calculating tissue doses on the basis of results from Th-230 and Th-232 (with daughter products) in tissue samples of animals after administration of normal and enriched thorotrast. (orig./HP)

  13. Optimizing nucleic acid extraction from thyroid fine-needle aspiration cells in stained slides, formalin-fixed/paraffin-embedded tissues, and long-term stored blood samples

    Marina M. L. Kizys

    2012-12-01

    Full Text Available OBJECTIVE: Adequate isolation of nucleic acids from peripheral blood, fine-needle aspiration cells in stained slides, and fresh and formalin-fixed/paraffin-embedded tissues is crucial to ensure the success of molecular endocrinology techniques, especially when samples are stored for long periods, or when no other samples can be collected from patients who are lost to follow-up. Here, we evaluate several procedures to improve current methodologies for DNA (salting-out and RNA isolation. MATERIALS AND METHODS: We used proteinase K treatment, heat shock, and other adaptations to increase the amount and quality of the material retrieved from the samples. RESULTS: We successfully isolated DNA and RNA from the samples described above, and this material was suitable for PCR, methylation profiling, real-time PCR and DNA sequencing. CONCLUSION: The techniques herein applied to isolate nucleic acids allowed further reliable molecular analyses. Arq Bras Endocrinol Metab. 2012;56(9:618-26

  14. 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...

  15. Rate of Recovery of Mycobacterium tuberculosis from Frozen Acid-Fast-Bacillus Smear-Positive Sputum Samples Subjected to Long-Term Storage in Northwest Ethiopia ▿

    Tessema, Belay; Beer, Joerg; Emmrich, Frank; Sack, Ulrich; Rodloff, Arne C

    2011-01-01

    Tuberculosis is a major public health problem in Ethiopia. The diagnosis and treatment of drug-resistant tuberculosis remain a challenge in the country. This study aimed to assess whether single morning sputum samples could be stored at −20°C for extended periods of time at remote settings and then transported and successfully cultured for Mycobacterium tuberculosis. Single morning sputum samples were collected from all smear-positive tuberculosis patients diagnosed at Gondar Hospital, Gondar...

  16. Nuclear Energy, Long Term Requirements

    There are serious warnings about depletion of oil and gas and even more serious warnings about dangers of climate change caused by emission of carbon dioxide. Should developed countries be called to replace CO2 emitting energy sources as soon as possible, and the time available may not be longer then few decades, can nuclear energy answer the call and what are the requirements? Assuming optimistic contribution of renewable energy sources, can nuclear energy expand to several times present level in order to replace large part of fossil fuels use? Paper considers intermediate and long-term requirements. Future of nuclear power depends on satisfactory answers on several questions. First group of questions are those important for near and intermediate future. They deal with economics and safety of nuclear power stations in the first place. On the same time scale a generally accepted concept for radioactive waste disposal is also required. All these issues are in the focus of present research and development. Safer and more economical reactors are targets of international efforts in Generation IV and INPRO projects, but aiming further ahead these innovative projects are also addressing issues such as waste reduction and proliferation resistance. However, even assuming successful technical development of these projects, and there is no reason to doubt it, long term and large-scale nuclear power use is thereby not yet secured. If nuclear power is to play an essential role in the long-term future energy production and in reduction of CO2 emission, than several additional questions must be replied. These questions will deal with long-term nuclear fuel sufficiency, with necessary contribution of nuclear power in sectors of transport and industrial processes and with nuclear proliferation safety. This last issue is more political then technical, thus sometimes neglected by nuclear engineers, yet it will have essential role for the long-term prospects of nuclear power. The status of the intermediate and long-term issues will be discussed, with special attention to the nuclear proliferation issue in view of unfavourable recent development, such as failure of 2005 NPT renewal conference and the Iran and North Korea cases. It will be argued that nuclear proliferation threat is the only really serious obstacle to the large-scale use of nuclear energy. In positive political environment solution of this problem could be possible on the lines of the very early US proposal (so called Baruch plan, UN 1946). Present political developments appear to demand renewed attempt to internationalize proliferation sensitive fuel cycle installations. Reasons will be discussed for a conviction that prospects for this may be better than in 1946. (author)

  17. 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. PMID:23986109

  18. 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

    admixture proportions showed a small genetic contribution from domesticated trout (approximately 6%), and individual admixture analysis demonstrated a majority of nonadmixed individuals. The expected genetic contribution by domesticated trout was 64%, assessed from the number of stocked trout and assuming...... 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...

  19. 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; Astrup, Thomas Fruergaard

    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...

  20. Long-term Video-EEG Monitoring for Paroxysmal Events

    Ying-Ying Lee; Mei-Ying Lee; Yu-Tai Tsai; Chung-Yang Sung; Hsiang-Yao Hsieh; Siew-Na Lim; Peter Wu Hung; Tony Wu; I-an Chen

    2009-01-01

    Background: Long term video-electroencephalography monitoring (VEM) has been widelyused for the diagnosis, classification, and management of seizures. Fewstudies have systemically examined its safety issues and clinical utility. Thisprospective study investigates the general clinical application of long termVEM in the management of paroxysmal events.Methods: This study cohort consisted of patients admitted to the inpatient VEM unit atChang Gung Memorial Hospital (Lin-Kou). Standard 19 channel...

  1. Long term radioactive waste management

    In France, waste management, a sensitive issue in term of public opinion, is developing quickly, and due to twenty years of experience, is now reaching maturity. With the launching of the French nuclear programme, the use of radioactive sources in radiotherapy and industry, waste management has become an industrial activity. Waste management is an integrated system dealing with the wastes from their production to the long term disposal, including their identification, sortage, treatment, packaging, collection and transport. This system aims at guaranteing the protection of present and future populations with an available technology. In regard to their long term management, and the design of disposals, radioactive wastes are divided in three categories. This classification takes into account the different radioisotopes contained, their half life and their total activity. Presently short-lived wastes are stored in the shallowland disposal of the ''Centre de la Manche''. Set up within the French Atomic Energy Commission (CEA), the National Agency for waste management (ANDRA) is responsible within the framework of legislative and regulatory provisions for long term waste management in France

  2. Performance in Omics Analyses of Blood Samples in Long-Term Storage: Opportunities for the Exploitation of Existing Biobanks in Environmental Health Research

    Hebels, Dennie G.A.J.; Georgiadis, Panagiotis; Keun, Hector C.; Athersuch, Toby J.; Vineis, Paolo; Vermeulen, Roel; Portengen, Lutzen; Bergdahl, Ingvar A.; Hallmans, Göran; Palli, Domenico; Bendinelli, Benedetta; Krogh, Vittorio; Tumino, Rosario; Sacerdote, Carlotta; Panico, Salvatore

    2013-01-01

    Background: The suitability for omic analysis of biosamples collected in previous decades and currently stored in biobanks is unknown. Objectives: We evaluated the influence of handling and storage conditions of blood-derived biosamples on transcriptomic, epigenomic (CpG methylation), plasma metabolomic [UPLC-ToFMS (ultra performance liquid chromatography–time-of-flight mass spectrometry)], and wide-target proteomic profiles. Methods: We collected fresh blood samples without RNA preservative ...

  3. Rate of recovery of Mycobacterium tuberculosis from frozen acid-fast-bacillus smear-positive sputum samples subjected to long-term storage in Northwest Ethiopia.

    Tessema, Belay; Beer, Joerg; Emmrich, Frank; Sack, Ulrich; Rodloff, Arne C

    2011-07-01

    Tuberculosis is a major public health problem in Ethiopia. The diagnosis and treatment of drug-resistant tuberculosis remain a challenge in the country. This study aimed to assess whether single morning sputum samples could be stored at -20 °C for extended periods of time at remote settings and then transported and successfully cultured for Mycobacterium tuberculosis. Single morning sputum samples were collected from all smear-positive tuberculosis patients diagnosed at Gondar Hospital, Gondar Health Center, Metemma Hospital, Bahir Dar Hospital, and Debre Markos Hospital in Northwest Ethiopia between March and July 2009. Specimens were stored at the study sites and sent to the mycobacteriology laboratory at the University Hospital, Leipzig, Germany, where specimens were processed and inoculated into the BacT/Alert 3D system and Lowenstein-Jensen and Gottsacker media. Ice packs were added in the package of the specimens during transport. A total of 319 patients were enrolled in this study. The median specimen storage time was 132 days (range, 16 to 180 days). Of all specimens, 283 (88.7%) were culture positive by any of the three culturing systems. M. tuberculosis isolates from four contaminated specimens in all culturing systems were successfully isolated on Middlebrook 7H10 agar; thereby, the recovery rate increased to 287 (90.0%). The length of time of sputum storage had no significant effect on the rate of recovery of M. tuberculosis in all culturing systems. In conclusion, single morning sputum specimens collected at remote settings stored at -20 °C for long periods of time without the addition of preservatives can yield a high recovery rate. These findings suggest a simple and cost-effective alternative method of sputum storage for epidemiological and drug resistance studies in low-resource countries. PMID:21562105

  4. 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.

  5. Capture of a protein synthesis-dependent component of long-term depression

    Kauderer, Beth S.; Kandel, Eric R.

    2000-01-01

    Hippocampal-based behavioral memories and hippocampal-based forms of synaptic plasticity, such as long-term potentiation, are divisible into short- and long-term phases, with the long-term phase requiring the synthesis of new proteins and mRNA for its persistence. By contrast, it is less clear whether long-term depression (LTD) can be divisible into phases. We here describe that in stable hippocampal organotypic cultures, LTD also is not a unitary event but a multiphas...

  6. Long-term neuropsychological outcomes following mild traumatic brain injury.

    Vanderploeg, Rodney D; Curtiss, Glenn; Belanger, Heather G

    2005-05-01

    Mild traumatic brain injury (MTBI) is common, yet few studies have examined neuropsychological outcomes more than 1 year postinjury. Studies of nonreferred individuals with MTBI or studies with appropriate control groups are lacking, but necessary to draw conclusions regarding natural recovery from MTBI. We examined the long-term neuropsychological outcomes of a self-reported MTBI an average of 8 years postinjury in a nonreferred community-dwelling sample of male veterans. This was a cross-sectional cohort study derived from the Vietnam Experience Study. Three groups matched on premorbid cognitive ability were examined, those who (1) had not been injured in a MVA nor had a head injury (Normal Control; n = 3214), (2) had been injured in a motor vehicle accident (MVA) but did not have a head injury (MVA Control; n = 539), and (3) had a head injury with altered consciousness (MTBI; n = 254). A MANOVA found no group differences on a standard neuropsychological test battery of 15 measures. Across 15 measures, the average neuropsychological effect size of MTBI compared with either control group was -.03. Subtle aspects of attention and working memory also were examined by comparing groups on Paced Auditory Serial Addition Test (PASAT) continuation rate and California Verbal Learning Test (CVLT) proactive interference (PI). Compared with normal controls, the MTBI group evidenced attention problems in their lower rate of continuation to completion on the PASAT (odds ratio = 1.32, CI = 1.0-1.73) and in excessive PI (odds ratio = 1.66, CI = 1.11-2.47). Unique to the MTBI group, PASAT continuation problems were associated with left-sided visual imperceptions and excessive PI was associated with impaired tandem gait. These results show that MTBI can have adverse long-term neuropsychological outcomes on subtle aspects of complex attention and working memory. PMID:15892899

  7. 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

    half of the children were tested by one, the other half by the other experimenter. At the follow-up, run by a naïve experimenter, the children were shown two videos from the original experiment in a visual paired comparison task: One with the specific experimenter testing them at the original visit...... (the Target) and one of the other experimenter (the Foil), with whom they had no experience. When explicitly asked, the children’s responses did not differ from chance. However, eye-tracking data revealed a late-manifesting novelty preference for the “Foil” person indicating memory for the “Target...

  8. What Does Long-Term Care Include?

    Full Text Available Video: "What Does Long-Term Care Include?" Long-term care involves a variety of services designed to meet a person's health or personal care needs during a short or long period of ...

  9. Long-term corrosion studies

    The scope of this activity is to assess the long-term corrosion properties of metallic materials under consideration for fabricating waste package containers. Three classes of metals are to be assessed: corrosion resistant, intermediate corrosion resistant, and corrosion allowance. Corrosion properties to be evaluated are general, pitting and crevice corrosion, stress-corrosion cracking, and galvanic corrosion. The performance of these materials will be investigated under conditions that are considered relevant to the potential emplacement site. Testing in four aqueous solutions, and vapor phases above them, and at two temperatures are planned for this activity. (The environmental conditions, test metals, and matrix are described in detail in Section 3.0.) The purpose and objective of this activity is to obtain the kinetic and mechanistic information on degradation of metallic alloys currently being considered for waste package containers. This information will be used to provide assistance to (1) waste package design (metal barrier selection) (E-20-90 to E-20-92), (2) waste package performance assessment activities (SIP-PA-2), (3) model development (E-20-75 to E-20-89). and (4) repository license application

  10. Long-term biosignals visualization and processing

    Gomes, Ricardo Rafael Baptista

    2011-01-01

    Long-term biosignals acquisitions are an important source of information about the patients’state and its evolution. However, long-term biosignals monitoring involves managing extremely large datasets, which makes signal visualization and processing a complex task. To overcome these problems, a new data structure to manage long-term biosignals was developed. Based on this new data structure, dedicated tools for long-term biosignals visualization and processing were implemented. A mul...

  11. Epilepsy-related long-term amnesia: anatomical perspectives.

    Butler, Chris; Kapur, Narinder; Zeman, Adam; Weller, Roy; Connelly, Alan

    2012-11-01

    There are few clues as to the neural basis of selective long-term amnesia. We report group and single-case data to shed light on this issue. In a group study of patients with transient epileptic amnesia, there were no significant correlations between volumetric measures of the hippocampus and indices of accelerated long-term forgetting or longer-term autobiographical memory loss. Post-mortem investigations in a patient with temporal lobe epilepsy who showed accelerated long-term forgetting, together with a degree of autobiographical memory loss, yielded evidence of neuronal loss and gliosis in regions of both the right and the left hippocampus. Neuronal loss and gliosis were more evident in anterior than posterior hippocampus. These results indicate that the unusual forms of long-term forgetting seen in some patients with temporal lobe epilepsy have no gross anatomical correlate. The findings leave open the possibilities that subtle structural damage or subtle functional disturbance, perhaps in the form of subclinical epileptiform activity, underly epilepsy-related long-term amnesia. PMID:22841993

  12. Differential Long-Term Effects of Haloperidol and Risperidone on the Acquisition and Performance of Tasks of Spatial Working and Short-Term Memory and Sustained Attention in Rats

    Hutchings, Elizabeth J.; Waller, Jennifer L.; Terry, Alvin V.

    2013-01-01

    A common feature of the neuropsychiatric disorders for which antipsychotic drugs are prescribed is cognitive dysfunction, yet the effects of long-term antipsychotic treatment on cognition are largely unknown. In the current study, we evaluated the effects of long-term oral treatment with the first-generation antipsychotic haloperidol (1.0 and 2.0 mg/kg daily) and the second-generation antipsychotic risperidone (1.25 and 2.5 mg/kg daily) on the acquisition and performance of two radial-arm maz...

  13. [Long-term use of benzodiazepines].

    Gorgels, W J; Oude Voshaar, R C; Mol, A J; Breteler, M H; van de Lisdonk, E H; Zitman, F G

    2001-07-14

    Benzodiazepines are the most prescribed drugs in the Netherlands. There is scarcely an indication for long-term benzodiazepine use. Long-term use may lead to dependency and is associated with an increased risk of accidents/falls and cognitive function impairment. Therefore national and international guidelines advocate a conservative prescription policy, especially with respect to long-term prescription. It appears that these guidelines are not followed in practice. A standard sized general practice in the Netherlands contains, on average, 75 long-term benzodiazepine users. There appear to be both patient and GP related factors which influence the maintenance of this long-term use of benzodiazepines. PMID:11484430

  14. 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 which short-term memories are permanently stored, and b) a strong foundation for continued growth of an excellent undergraduate neuroscience program.

  15. Evaluation of the effects of long-term storage of bovine ear notch samples on the ability of 2 diagnostic assays to identify calves persistently infected with bovine viral diarrhoea virus

    F, Khan; J H, Vorster; M, van Vuuren; P, Mapham.

    Full Text Available Research aimed at optimising diagnostic laboratory procedures is central to the development of effective bovine viral diarrhoea virus (BVDV) control programmes. BVDV is a singlestranded RNA virus that crosses the placenta to infect foetuses, resulting in reproductive losses due to foetal death or pe [...] rsistently infected calves that die early in life. Persistently infected animals are widely accepted to be the primary reservoir of BVDV and the largest source of infection. This poses important challenges to overall animal/herd health and can cause major losses to the cattle industry. Long-term storage of bovine ear notch samples from calves persistently infected with BVDV may adversely affect the ability of diagnostic assays to detect the virus efficiently. In order to test this hypothesis, ear notch samples from 7 animals were divided into 2 groups. One set was subjected to prompt formalin fixation and the other set stored either as fresh samples without preservatives at -2 ºC, or soaked overnight in phosphate buffered saline followed by freezing of the supernatant fluid at -2 ºC. Frozen ear notches and ear notch supernatant yielded positive results with an antigen-capture, enzyme linked immunosorbent assay (AC-ELISA) for the duration of the study (6 months) and optical density (OD) values remained significantly within range. There was no significant difference between storing fresh ear notch samples or PBS at -2 ºC. However, positive immunohistochemistry (IHC) staining on formalin fixed ear notches started to fade between Day 17 and Day 29 when stored at room temperature. It was concluded that fresh ear notches could safely be stored at -2 ºC for a period of 6 months prior to testing for BVD viral antigens

  16. Rasch analysis of the Mini-Mental Adjustment to Cancer Scale (mini-MAC among a heterogeneous sample of long-term cancer survivors: A cross-sectional study

    Zucca Alison

    2012-05-01

    Full Text Available Abstract Background The mini-Mental Adjustment to Cancer Scale (mini-MAC is a well-recognised, popular measure of coping in psycho-oncology and assesses five cancer-specific coping strategies. It has been suggested that these five subscales could be grouped to form the over-arching adaptive and maladptive coping subscales to facilitate the interpretation and clinical application of the scale. Despite the popularity of the mini-MAC, few studies have examined its psychometric properties among long-term cancer survivors, and further validation of the mini-MAC is needed to substantiate its use with the growing population of survivors. Therefore, this study examined the psychometric properties and dimensionality of the mini-MAC in a sample of long-term cancer survivors using Rasch analysis. Methods RUMM 2030 was used to analyse the mini-MAC data (n=851. Separate Rasch analyses were conducted for each of the original mini-MAC subscales as well as the over-arching adaptive and maladaptive coping subscales to examine summary and individual model fit statistics, person separation index (PSI, response format, local dependency, targeting, item bias (or differential item functioning -DIF, and dimensionality. Results For the fighting spirit, fatalism, and helplessness-hopelessness subscales, a revised three-point response format seemed more optimal than the original four-point response. To achieve model fit, items were deleted from four of the five subscales – Anxious Preoccupation items 7, 25, and 29; Cognitive Avoidance items 11 and 17; Fighting Spirit item 18; and Helplessness-Hopelessness items 16 and 20. For those subscales with sufficient items, analyses supported unidimensionality. Combining items to form the adaptive and maladaptive subscales was partially supported. Conclusions The original five subscales required item deletion and/or rescaling to improve goodness of fit to the Rasch model. While evidence was found for overarching subscales of adaptive and maladaptive coping, extensive modifications were necessary to achieve this result. Further exploration and validation of over-arching subscales assessing adaptive and maladaptive coping is necessary with cancer survivors.

  17. Toward a molecular definition of long-term memory storage

    Bailey, Craig H.; Bartsch, Dusan; Kandel, Eric R.

    1996-01-01

    The storage of long-term memory is associated with a cellular program of gene expression, altered protein synthesis, and the growth of new synaptic connections. Recent studies of a variety of memory processes, ranging in complexity from those produced by simple forms of implicit learning in invertebrates to those produced by more complex forms of explicit learning in mammals, suggest that part of the molecular switch required for consolidation of long-term memory is th...

  18. Long term sampling and measuring program. Joint report for 1987, 1988 and 1989. Within the project: Fallout studies in the Gideaa and Finnsjoe areas after the Chernobyl accident in 1986

    A redistribution and migration study of the Chernobyl fallout begun in 1986. It was realized in an early stage that the fallout from Chernobyl could be used as a large scale tracer study. After one early sampling and measurement it was concluded that at least five of the radioactive nuclides could be used in a long term perspective. The sorption and migration of these elements in geohydrological systems have been investigated during a period of three and a half years and a model of the redistribution is now prepared. The basis for successful modelling of the redistribution of fallout products within a small catchment area is dependent on accurate input. A repeated sampling of geological materials, and 'direct' measurement of gamma radiation in field, will then be needed. This report is a summary of the work that has been performed during 1987, 1988 and 1989 within sampling and measurement of radionuclide content in geological materials and surface vegetation. Migration studies and modelling work are other parts of the project that are not presented here. The collecting of field data is mainly done in a small catchment area (0.74 square km) c.30 km N-E of the city of Oernskoeldsvik county of Vaesternorrland. A minor field study is also done in an area east of Lake Finnsjoen, situated c.50 km north of the city of Uppsala. The conclusions that can be drawn from the Gideaa study site surface measurements are that the gamma radiation in general is decreasing with varying magnitude. But the picture is not all unambiguous. In the subsurface layers of studied soil profiles, an increase can be observed in the upper part of the enriched layer. The outflow of radionuclides with ground water seems to be fairly constant after the peak flow in 1986. Some indications of larger transport and outflow of radionuclides in connection with heavy rain or spring flood is also presented. (authors)

  19. Long-term criticality analyses process

    The process for evaluating long-term disposal criticality control in a potential repository is being developed to support long-term disposal as well as ensure the acceptance of the Multi-Purpose Canister (MPC). This paper outlines the current Waste Package Development process for performing long-term disposal criticality control evaluations. The process allows the entire time period of disposal criticality control to be evaluated with the issues for each time period addressed separately

  20. Financing long term liabilities (Germany)

    In Germany the basis for the management of radioactive residues is the polluter-pays principle. All steps of treatment of radioactive waste arising from operation, decommissioning and dismantling including conditioning, interim storage and disposal of radioactive waste have to be financed by the waste producers. The waste producers are responsible for the harmless recycling of the residues or for their orderly management as radioactive waste. The Federal Government is responsible for establishing disposal facilities. Accordingly the waste producers are constructing and operating facilities in which the radioactive residues can be treated and stored until their disposal. As far as the radioactive waste cannot be stored by the producer, waste originating from research, medicine and industry can be stored in surface storage facilities of the federal states. Spent fuel from German NPPs is partly reprocessed in France and UK. The rest has to be disposed off directly in deep geologic formations. Until a repository for spent fuel is available in Germany spent fuel will be stored in interim storage facilities on the sites of the NPPs. The storage will take place in casks in a dry way. In exceptional cases, if the storage at a NPP site is not possible, there are two central storages at Ahaus and Gorleben which are in operation and can be made available as reserve. Radioactive waste returning from the reprocessing of German spent fuel in France and UK is stored in the Gorleben central storage. The Federal Government is aiming to establish a repository in deep geological formations about the year 2030 which shall be available for all types and quantities of radioactive waste. The necessary expenses for the planning and construction of radioactive waste disposal facilities are initially carried by the Federal Government. The Government recovers the costs by contributions or advance payments from the waste producers. The use of storage and disposal facilities is financed by charges and fees levied from the waste producers. Altogether, financial resources for decommissioning are needed for the following steps: the post-operational phase in which the facility is prepared for dismantling after its final shut-down, dismantling of the radioactive part of the facility, management, storage and disposal of the radioactive waste, restoration of the site, licensing and regulatory supervision of all these steps. Additional means are necessary for the management, storage and disposal of the spent fuel. The way in which the availability of financial resources is secured differs between public owned installations and installations of the private power utilities. In Germany, past practices has resulted in singular contaminated sites of limited extent, mainly during the first half of the 20. century. Those contaminated sites have been or are being cleaned up and redeveloped. In large areas of Saxony and Thuringia, the geological formations permitted the surface and underground mining of Uranium ore. Facilities of the former Soviet-German WISMUT Ltd. where ore was mined and processed from 1946 until the early 1990's can be found at numerous sites. In the course of the re-unification of Germany, the soviet shares of the WISMUT were taken over by the Federal Republic of Germany and the closure of the WISMUT facilities was initiated. In that phase the extent of the damages to the environment and of the necessary remediation work became clear. All mining and milling sites are now closed and are under decommissioning. A comprehensive remediation concept covers all WISMUT sites. Heaps and mill-tailing ponds are transferred into a long-term stable condition. The area of the facilities to be remediated amounts to more than 30 km2. Heaps cover a total area of ca. 15,5 km2, tailing ponds in which the tailings resulting from the Uranium production are stored as sludges cover 6,3 km2). In total, the remediation issues are very complex and without precedent. The implementation of the measures will cover a period of 15 to 20 years depending on the site. The necess

  1. Long-term monitoring for closed sites

    A procedure is presented for planning and implementing a long-term environmental monitoring program for closed low-level radioactive waste disposal sites. The initial task in this procedure is to collect the available information on the legal/regulatory requirements, site and area characteristics, source term, pathway analysis, and prior monitoring results. This information is coupled with parameters such as half-life and retardation factors to develop a monitoring program. As examples, programs are presented for a site that has had little or no waste migration, and for sites where waste has been moved by suface water, by ground water, and by air. Sampling techniques and practices are discussed relative to how a current program would be structured and projections are made on techniques and practices expected to be available in the future. 8 refs., 2 figs

  2. Long-Term Care Ombudsman Program

    ... ACL Organization Authorizing Statutes Budget Mandatory Grant Allocations Strategic Plan Federal Initiatives Career Opportunities Contact Us Administration on Aging (AoA) Long-Term Care Ombudsman Program ( ...

  3. Defining a communication system for the long term

    Prof. Eleni Mitropoulou presented an ongoing study, undertaken on behalf of Andra, on long-term communication. The speaker highlighted that it is not so much the marking that needs to be sustainable, but above all what the marking communicates. She highlighted the importance of sustainable human action to produce memory and, thus, the need to reconcile the passive character of geological disposal and the active character of memory keeping. Focusing on semiotics, the interaction between the short, medium and long term was pointed out, highlighting the need to create a relay system. A multidimensional message was proposed, for the purposes of information ('storage site here'), interpellation (to warn, prevent or alert) and integration (with regard to the surrounding environment). This corresponds to the systemic approach of the RK and M initiative, which is based on a variety of RK and M transmission mechanisms that are integrated with and/or complement one another

  4. LONG TERM SYNAPTIC PLASTICITY IS IMPAIRED IN RATS WITH LESIONS OF THE VENTROLATERAL PREOPTIC NUCLEUS

    Arrigoni, Elda; Lu, Jun; Vetrivelan, Ramalingam; Saper, Clifford B

    2009-01-01

    Impairment of memory functions has been frequently reported in models of sleep deprivation. Similarly, hippocampal long-term synaptic plasticity has been shown to be sensitive to sleep loss due to acute sleep restriction. However, such approaches are limited by the stressful nature of sleep deprivation, and because it is difficult to study long term sleep restriction in animals. Here we report the effects of chronic sleep loss on hippocampal long-term potentiation (LTP) in a rodent model for ...

  5. Long Term Sorption Diffusion Experiment (LTDE-SD). Supporting laboratory program - Sorption diffusion experiments and rock material characterisation. With supplement of adsorption studies on intact rock samples from the Forsmark and Laxemar site investigations

    The LTDE-SD experiment, (Long Term Sorption Diffusion Experiment) aims at increasing the scientific knowledge of sorption and diffusion under in situ conditions and to provide data for performance and safety assessment calculations. In this report, performance and results of laboratory sorption and diffusion experiments and porosity investigations using site-specific crushed and intact rock materials are presented, including a geological and mineralogical characterization of the samples. A synthetic groundwater and a part of the radionuclide tracer cocktail that was used for the in situ experiment were used also in the laboratory experiments. 13 radionuclide tracers were analysed in the laboratory experiments. The method descriptions from SKB Site Investigations were applied in order to enable comparisons with Site Investigations data. The water saturation porosity of 10 unaltered matrix rock samples from KA3065A02 and A03 is 0.26 ± 0.08% and two fracture material samples show porosities of 2.4% and 5.2% respectively. 14C-methylmethacrylate impregnation (the PMMA-method) show that the unaltered rock matrix porosity is relatively homogeneous with grain boundary porosity, while the porosity of fracture samples is heterogeneous and have increased porosity up to more than 10% in some parts. Through-diffusion experiments using tritiated water (H3HO) give a matrix diffusivity in the range from 2.7·10-14 to 6.5·10-14 m2/s in four samples from KA3065A02 and A03. The results of the porosity and diffusion measurements are coherent in ranges with earlier LTDE-SD measurements and are also in line with the SKB Site Investigations results. In the batch sorption experiments using crushed rock material, two matrix rock samples of Aevroe granodiorite, one red-stained altered Aevroe granodiorite sample and two chlorite-calcite dominated fracture samples were analysed for three different size fractions as a function of time up to 186 days contact time. The strongest sorption was observed in the fracture material samples. The two matrix rock samples and the altered sample showed nearly the same sorption properties. Kd values in the range from 1·10-3 to 1 m3/kg could be detected with the method. The individual results for different tracers and species are interpreted in the report. Sorption-diffusion on intact rock samples showed concentration losses that were basically in line to what could be expected from the outcome of the batch sorption experiments within the LTDE-SD and the Site Investigation program. Modelling of the diffusion process showed that the product of the sorption coefficient and the formation factor, Kd·Ff, can only be resolved by analysis of the tracer concentration profiles in the rock

  6. Long Term Sorption Diffusion Experiment (LTDE-SD). Supporting laboratory program - Sorption diffusion experiments and rock material characterisation. With supplement of adsorption studies on intact rock samples from the Forsmark and Laxemar site investigations

    Widestrand, Henrik; Byegaard, Johan; Selnert, Eva; Skaalberg, Mats; Hoeglund, Susanne; Gustafsson, Erik (Geosigma AB, Uppsala (Sweden))

    2010-12-15

    The LTDE-SD experiment, (Long Term Sorption Diffusion Experiment) aims at increasing the scientific knowledge of sorption and diffusion under in situ conditions and to provide data for performance and safety assessment calculations. In this report, performance and results of laboratory sorption and diffusion experiments and porosity investigations using site-specific crushed and intact rock materials are presented, including a geological and mineralogical characterization of the samples. A synthetic groundwater and a part of the radionuclide tracer cocktail that was used for the in situ experiment were used also in the laboratory experiments. 13 radionuclide tracers were analysed in the laboratory experiments. The method descriptions from SKB Site Investigations were applied in order to enable comparisons with Site Investigations data. The water saturation porosity of 10 unaltered matrix rock samples from KA3065A02 and A03 is 0.26 +- 0.08% and two fracture material samples show porosities of 2.4% and 5.2% respectively. 14C-methylmethacrylate impregnation (the PMMA-method) show that the unaltered rock matrix porosity is relatively homogeneous with grain boundary porosity, while the porosity of fracture samples is heterogeneous and have increased porosity up to more than 10% in some parts. Through-diffusion experiments using tritiated water (H3HO) give a matrix diffusivity in the range from 2.7centre dot10-14 to 6.5centre dot10-14 m2/s in four samples from KA3065A02 and A03. The results of the porosity and diffusion measurements are coherent in ranges with earlier LTDE-SD measurements and are also in line with the SKB Site Investigations results. In the batch sorption experiments using crushed rock material, two matrix rock samples of Aevroe granodiorite, one red-stained altered Aevroe granodiorite sample and two chlorite-calcite dominated fracture samples were analysed for three different size fractions as a function of time up to 186 days contact time. The strongest sorption was observed in the fracture material samples. The two matrix rock samples and the altered sample showed nearly the same sorption properties. K{sub d} values in the range from 1centre dot10-3 to 1 m3/kg could be detected with the method. The individual results for different tracers and species are interpreted in the report. Sorption-diffusion on intact rock samples showed concentration losses that were basically in line to what could be expected from the outcome of the batch sorption experiments within the LTDE-SD and the Site Investigation program. Modelling of the diffusion process showed that the product of the sorption coefficient and the formation factor, K{sub d}centre dotF{sub f}, can only be resolved by analysis of the tracer concentration profiles in the rock

  7. Long-term preservation of Anammox bacteria

    Deposit of useful microorganisms in culture collections requires long-term preservation and successful reactivation techniques. The goal of this study was to develop a simple preservation protocol for the long-term storage and reactivation of the anammox biomass. To achieve this, anammox biomass w...

  8. Simulations Suggest Pharmacological Methods for Rescuing Long-Term Potentiation

    Smolen, Paul; Baxter, Douglas A; Byrne, John H.

    2014-01-01

    Congenital cognitive dysfunctions are frequently due to deficits in molecular pathways that underlie the induction or maintenance of synaptic plasticity. For example, Rubinstein-Taybi syndrome (RTS) is due to a mutation in cbp, encoding the histone acetyltransferase CREB-binding protein (CBP). CBP is a transcriptional co-activator for CREB, and induction of CREB-dependent transcription plays a key role in long-term memory (LTM). In animal models of RTS, mutations of cbp impair LTM and late-ph...

  9. Concept Formation Skills in Long-Term Cochlear Implant Users

    Castellanos, Irina; Kronenberger, William G.; de Beer, Jessica; Colson, Bethany G.; Henning, Shirley C.; Ditmars, Allison; PISONI, DAVID B.

    2014-01-01

    This study investigated if a period of auditory sensory deprivation followed by degraded auditory input and related language delays affects visual concept formation skills in long-term prelingually deaf cochlear implant (CI) users. We also examined if concept formation skills are mediated or moderated by other neurocognitive domains (i.e., language, working memory, and executive control). Relative to normally hearing (NH) peers, CI users displayed significantly poorer performance in several s...

  10. 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.

  11. Financing Purchase of long-term Property

    Pastyřík, Jaroslav

    2012-01-01

    Bachelor’s thesis is focused on issues of financing a purchase of long-term property in specific company. Particular variations of purchase and financing of fixed assets are described in the teoretical part of the thesis, presentation of the specific company and long-term property that is purchased and variations of financing are described in the practical part of the thesis. The aim of the thesis is to assess possible recources of financing purchase of long-term property in the specific comp...

  12. 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.

  13. Long-Term Low-Level Arsenic Exposure Is Associated with Poorer Neuropsychological Functioning: A Project FRONTIER Study

    Robert Barber

    2011-03-01

    Full Text Available Exposure to elements in groundwater (toxic or beneficial is commonplace yet, outside of lead and mercury, little research has examined the impact of many commonly occurring environmental exposures on mental abilities during the aging process. Inorganic arsenic is a known neurotoxin that has both neurodevelopmental and neurocognitive consequences. The aim of this study was to examine the potential association between current and long-term arsenic exposure and detailed neuropsychological functioning in a sample of rural-dwelling adults and elders. Data were analyzed from 434 participants (133 men and 301 women of Project FRONTIER, a community-based participatory research study of the epidemiology of health issues of rural-dwelling adults and elders. The results of the study showed that GIS-based groundwater arsenic exposure (current and long-term was significantly related to poorer scores in language, visuospatial skills, and executive functioning. Additionally, long-term low-level exposure to arsenic was significantly correlated to poorer scores in global cognition, processing speed and immediate memory. The finding of a correlation between arsenic and the domains of executive functioning and memory is of critical importance as these are cognitive domains that reflect the earliest manifestations of Alzheimer’s disease. Additional work is warranted given the population health implications associated with long-term low-level arsenic exposure.

  14. 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 linguistically diverse backgrounds (including Aboriginal and Torres Strait Islander origin. Diabetes MILES--Australia represents a major achievement in the study of diabetes in Australia, where for the first time, the focus is on psychosocial and behavioural aspects of this condition at a national level.

  15. 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...

  16. Long Term Effects of Food Poisoning

    ... meningitis, an inflammation of the membranes surrounding the brain. If a newborn infant is infected with Listeria , long-term consequences may include mental retardation, seizures, paralysis, blindness, or deafness. Guillain-Barré syndrome is a ...

  17. Long-term outcome after coronary stenting

    Hall Donald

    2000-08-01

    Full Text Available Abstract The present review assesses the data on long-term outcome after coronary stenting. Histological, angiographical and intravascular imaging data have shown that the insertion of stents constitutes only a transient stimulus to lumen renarrowing, that this process is almost complete at 6 months and that a certain degree of neointima regression is also possible after this time. Clinical data have confirmed the sustained benefit of stenting in the long term. Careful selection of optimal stent designs and application of the recent advances in adjunctive pharmacological therapy are currently effective strategies to improve both short-and long-term results with coronary stenting. However, further efforts are needed and are ongoing to combat restenosis, a process that counters the excellent short-term results of stenting in the long term.

  18. 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...

  19. Long term wet spent nuclear fuel storage

    The meeting showed that there is continuing confidence in the use of wet storage for spent nuclear fuel and that long-term wet storage of fuel clad in zirconium alloys can be readily achieved. The importance of maintaining good water chemistry has been identified. The long-term wet storage behaviour of sensitized stainless steel clad fuel involves, as yet, some uncertainties. However, great reliance will be placed on long-term wet storage of spent fuel into the future. The following topics were treated to some extent: Oxidation of the external surface of fuel clad, rod consolidation, radiation protection, optimum methods of treating spent fuel storage water, physical radiation effects, and the behaviour of spent fuel assemblies of long-term wet storage conditions. A number of papers on national experience are included

  20. Institutionalization and Organizational Long-term Success

    Denise L. Fleck

    2007-01-01

    Institutionalization processes have an ambivalent effect on organizational long-term success. Even though they foster organizational stability and permanence, they also bring about rigidity and resistance to change. As a result, successful organizations are likely to lose their competitive advantage over time. The paper addresses this issue through the investigation of the institutionalization processes of two long-lived companies: General Electric, a firm that has been a long-term success an...

  1. Manganese in long term paediatric parenteral nutrition.

    Reynolds, A. P.; Kiely, E; Meadows, N.

    1994-01-01

    The current practice of providing manganese supplementation to neonates on long term parenteral nutrition is leading to a high incidence of hypermanganesaemia. Magnetic resonance imaging (MRI) studies in adults on long term manganese parenteral nutrition have shown changes in TI weighted MRI images and similar findings in a neonate receiving trace element supplementation are reported here. Whole blood manganese concentration in the infant was 1740 nmol/l (or 8.3 times upper reference limit). ...

  2. 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 sensors housed in anti-fouling sensor chambers. The monitoring network is highly versatile and can be applied to a variety of subsurface sensing scenarios in different media. However, the current project focused on monitoring water quality parameters of pH, oxidation-reduction potential, conductivity, and temperature in groundwater.

  3. Robotics for Long-Term Monitoring

    While long-term monitoring and stewardship means many things to many people, DOE has defined it as The physical controls, institutions, information, and other mechanisms needed to ensure protection of people and the environment at sites where DOE has completed or plans to complete cleanup (e.g., landfill closures, remedial actions, and facility stabilization). Across the United States, there are thousands of contaminated sites with multiple contaminants released from multiple sources where contaminants have transported and commingled. The U.S. government and U.S. industry are responsible for most of the contamination and are landowners of many of these contaminated properties. These sites must be surveyed periodically for various criteria including structural deterioration, water intrusion, integrity of storage containers, atmospheric conditions, and hazardous substance release. The surveys, however, are intrusive, time-consuming, and expensive and expose survey personnel to radioactive contamination. In long-term monitoring, there's a need for an automated system that will gather and report data from sensors without costly human labor. In most cases, a SCADA (Supervisory Control and Data Acquisition) unit is used to collect and report data from a remote location. A SCADA unit consists of an embedded computer with data acquisition capabilities. The unit can be configured with various sensors placed in different areas of the site to be monitored. A system of this type is static, i.e., the sensors, once placed, cannot be moved to other locations within the site. For those applications where the number of sampling locations would require too many sensors, or where exact location of future problems is unknown, a mobile sensing platform is an ideal solution. In many facilities that undergo regular inspections, the number of video cameras and air monitors required to eliminate the need for human inspections is very large and far too costly. HCET's remote harsh-environment surveyor (RHES) is a robotic platform with SCADA capabilities equipped with a sonar-imaging scanner, a high-resolution color CCD camera, and various combinations of sensors. The RHES is controlled remotely via a PC. This paper will discuss the development and application of this system. (authors)

  4. Coincident Activity of Converging Pathways Enables Simultaneous Long-Term Potentiation and Long-Term Depression in Hippocampal CA1 Network In Vivo

    Dong, Zhifang; Han, Huili; Cao, Jun; Zhang, Xia; Lin XU

    2008-01-01

    Memory is believed to depend on activity-dependent changes in the strength of synapses, e.g. long-term potentiation (LTP) and long-term depression (LTD), which can be determined by the sequence of coincident pre- and postsynaptic activity, respectively. It remains unclear, however, whether and how coincident activity of converging efferent pathways can enable LTP and LTD in the pathways simultaneously. Here, we report that, in pentobarbital-anesthetized rats, stimulation (600 pulses, 5 Hz) to...

  5. Long-term costs of colorectal cancer treatment in Spain

    Corral, Julieta; Castells, Xavier; Molins, Eduard; Chiarello, Pietro; Borras, Josep Maria; Cots, Francesc

    2016-01-01

    Background Assessing the long-term cost of colorectal cancer (CRC) increases our understanding of the disease burden. The aim of this paper is to estimate the long-term costs of CRC care by stage at diagnosis and phase of care in the Spanish National Health Service. Methods Retrospective study on resource use and direct medical cost of a cohort of 699 patients diagnosed and treated for CRC in 2000–2006, with follow-up until 30 June 2011, at Hospital del Mar (Barcelona). The Kaplan-Meier sampl...

  6. Long-term stability scintillation tiles for LHCb detector

    Grinyov, B V; Khlapova, N P; Lebedev, V N; Melnychuk, S V; Senchyshyn, V G; 10.1016/j.radmeas.2004.02.018

    2004-01-01

    Accelerated thermal aging tests of materials-UPS-923A, UPS-96G, UPS-96GM and their analogues, SCSN-81 (Kuraray) and BC-408 (Bicron)- were made. A forecast of tile lifetime was made for normal conditions of usage (20% reduction of light output and 50% reduction of the bulk attenuation length (BAL) and technical attenuation length (TAL). Scintillator UPS-96GM has the most long-term stability of parameters- more than 11 yr. BC-408 samples have the minimum lifetime ~7 yr. The long-term stability, calculated by light yield reduction, of UPS-96G, UPS-923A and SCSN-81 is 10, 9 and 8 yr, respectively.

  7. [Health Promotion for Long-Term Unemployed Persons].

    Limm, H; Gündel, H; Heinmüller, M; Liel, K; Seeger, K; Angerer, P

    2015-09-01

    A controlled trial to improve perceived health in a sample of long-term unemployed persons was conducted. As primary endpoint the SF12-questionnaire was used. The intervention was tailored to the specific needs of the long-term unemployed combining individual sessions based on motivational interviewing and group sessions designed with the participation of the participants. 365 participants were enrolled in the study. 287 or, respectively, 148 unemployed persons participated at the 3-months/12-months follow-up assessments. A positive effect of the intervention in the setting of long-term unemployed persons has been shown for perceived health, mental health and changes towards more physical activity and healthier nutrition. PMID:23553185

  8. Collaboration of geldanamycin-activated P70S6K and Hsp70 against beta-amyloid-induced hippocampal apoptosis: an approach to long-term memory and learning.

    Zare, Nayereh; Motamedi, Fereshteh; Digaleh, Hadi; Khodagholi, Fariba; Maghsoudi, Nader

    2015-03-01

    One of the neuropathological hallmarks of Alzheimer's disease (AD) is the accumulation of beta-amyloid peptides (A?) in senile plaques. A?-induced oxidative stress is believed to be responsible for degeneration and apoptosis of neurons and consequent cognitive and memory deficits. Here, we investigated the possible neuroprotective effect of the heat shock protein 90 (Hsp90) inhibitor geldanamycin (GA) against amyloid pathogenesis in adult male Wistar rats. GA or vehicle was injected into the lateral cerebral ventricles of rats 24 h before injection of A? (1-42) in CA1 area of hippocampus. The learning and memory of the rats were assessed 7 days after injection of A? using passive avoidance (PA) task. As potential contributing factors in A?-induced memory decline, we evaluated apoptotic markers and also used terminal-transferase UTP nick end labeling (TUNEL) technique to detect apoptosis in the hippocampus of A?-injected rats. Our behavioral data suggest that GA pretreatment can significantly suppress memory deficits in A?-injected rats. There was also not only a marked increase in Hsp70 level but also upregulated 70 kDa ribosomal protein S6 kinase (p70S6K) in the hippocampus of GA-treated groups with a reduction in apoptotic factors including caspase-3, poly (ADP-ribose) polymerase, Bax/Bcl-2 ratio, and TUNEL-positive cells as well. Thus, we conclude that GA exerts its protective effects against A? (1-42) toxicity and memory deficits, at least in part, by upregulating of Hsp70 and P70S6K. PMID:25576151

  9. Long-term prisoner in prison isolation

    Karolina Grudzi?ska

    2013-06-01

    Full Text Available Long-term prisoner belongs to a particular category of people who are imprisoned in prisons. On the one hand in this group are often heavily demoralized people who committed the most serious crimes, on the other hand it is a group of prisoners, who should be well thought out and programmed the impact of rehabilitation. The situation of man trapped for years poses in a complicated situation not only the prisoners, but also the entire prison staff. They have to take care of the fact that the prison isolation did not cause the state in which convicts form itself in learned helplessness and lack of skills for self-planning and decision-making. In addition, planning the rehabilitation impact of long-term prisoners should not be forgotten that these prisoners in the short or the long term will return to the libertarian environment therefore, should prevent any negative effects of long-term imprisonment. This article presents the main issues related to the execution of imprisonment against long-term prisoners. It is an attempt to systematize the knowledge of this category of people living in prison isolation.

  10. Long-term alteration of cementitious materials

    Long-term alteration of cementitious materials in the geological condition has been discussed for the safety assessment of radioactive waste disposal. This paper describes the status of understanding long-term chemical alteration of cement, by reviewing some of our investigations on this issue in which we developed a thermodynamic incongruent C-S-H dissolution/precipitation model and a reactive transport calculation code. Alteration of C-S-H gel in a saline groundwater and the change of chemical barrier performance of cementitious materials due to the alteration are also discussed. Some key issues to be discussed further are given and suggested for the future studies on the long-term alteration of cementitious materials in the repository environment. (author)

  11. The long-term stability of new hippocampal place fields requires new protein synthesis

    Agnihotri, Naveen T.; Hawkins, Robert D.; Kandel, Eric R.; Kentros, Clifford

    2004-01-01

    The hippocampus is critical for formation of spatial memories. Hippocampal pyramidal neurons in freely behaving animals exhibit spatially selective firing patterns, which taken together form an internal representation of the environment. This representation is thought to contribute to the hippocampal spatial memory system. Behavioral long-term memories differ from short-term memories in requiring the synthesis of new proteins. Does the development of the internal hippocampal representation al...

  12. Long term planning for wind energy development

    In a planning system intended to be governed primarily by policies in statutory plans a reasonable horizon for long term planning is 10 years or longer. Because of statutory requirements, developers have no option but to pay due regard to, and take a full part in, long term planning. The paper examines the type of policies which have emerged in the last few years to cater for wind energy development. It canvasses the merits of different types of policies. Finally, it discusses the policy framework which may emerge to cater for development outside NFFO. (Author)

  13. Explaining Long Term Trends in Violent Crime

    Thome, Helmut

    2009-01-01

    Gurr and others have demonstrated that the long-term development of homicide rates in Europe follows a U-shaped curve : There is a fairly steady (though non-linear) decline since the 17th century (or even earlier, in some regions) till the middle of the 20th century, and a fairly steady increase since the 1960s. It is tentatively assumed in this article that the increase in the second half of the 20th century does not indicate a temporary deviation from the long-term trend but rather a trend ...

  14. Nonproliferation: a long-term strategy

    This long-term appraisal of the nonproliferation policy attempts to put into focus the key elements of the policy as they have emerged over the period since President Carter's election and to assess these elements in a long-term context. One of the major accomplishments of the policy is seen as raising the level of concern about proliferation both in the US and abroad. Certain beginnings of an international institutional response are cited. Evidence is given to indicate that a period of reexamination and redirection of nuclear technology is beginning

  15. Long-term consequences of foodborne infections.

    Batz, Michael B; Henke, Evan; Kowalcyk, Barbara

    2013-09-01

    Foodborne infections with Campylobacter, E. coli O157:H7, Listeria monocytogenes, Salmonella, Shigella, Toxoplasma gondii, and other pathogens can result in long-term sequelae to numerous organ systems. These include irritable bowel syndrome, inflammatory bowel disease, reactive arthritis, hemolytic uremic syndrome, chronic kidney disease, Guillain-Barré Syndrome, neurological disorders from acquired and congenital listeriosis and toxoplasmosis, and cognitive and developmental deficits due to diarrheal malnutrition or severe acute illness. A full understanding of the long-term sequelae of foodborne infection is important both for individual patient management by clinicians, as well as to inform food safety and public health decision making. PMID:24011832

  16. Hippocampal BDNF content in response to short- and long-term exercise.

    Sheikhzadeh, Farzam; Etemad, Asieh; Khoshghadam, Sahar; Asl, Naser Ahmadi; Zare, Peyman

    2015-07-01

    The hippocampus is a region in the brain that is crucial for learning and memory. Previous researches proved that brain-derived neurotrophic factor (BDNF) is a probable responsible protein in the learning and memory formation process. BDNF content is thought to be affected by environmental enrichment and physical activity. The purpose of this research was to identify the effect of short- and long-term forced exercise on hippocampal BDNF levels. A total of 30 Wistar rats were randomly divided into three groups (control, short-term exercise and long-term exercise) and treated by treadmill running based on their group. As the treadmill running period finished, the animals were anesthetized. The hippocampus was dissected out immediately and BDNF content of the samples was assessed by ELISA. None of the exercise paradigms did make any significant change on hippocampal BDNF levels. Although exercise was proposed to up-regulate BDNF levels, these results show that the intensity or the duration of running paradigm used in forced exercise protocols here was not enough to affect BDNF levels in the hippocampus significantly. PMID:25860428

  17. Long term charge retention dynamics of SONOS cells

    Arreghini, A.; Akil, N.; Driussi, F.; Esseni, D.; Selmi, L.; van Duuren, M. J.

    2008-09-01

    We present a model for charge retention dynamics in SONOS non volatile memory cells which accounts for the space and energy distributions of the trapped charge in the silicon nitride, self consistently with the potential. Long term retention measurements (beyond 106 s) versus temperature allowed us to decouple two charge loss mechanisms, to calibrate the model parameters and then to reproduce a large set of measurements on devices featuring different gate stacks, initial threshold voltages (including negative ones) and operation temperatures. A detailed analysis has been also carried out to compare the retention dynamics of cells featuring thin or thick tunnel oxide barriers.

  18. Long-Term Memory Deficits are Associated with Elevated Synaptic ERK1/2 Activation and Reversed by mGluR5 Antagonism in an Animal Model of Autism

    Seese, Ronald R; Maske, Anna R; Lynch, Gary; Gall, Christine M

    2014-01-01

    A significant proportion of patients with autism exhibit some degree of intellectual disability. The BTBR T+ Itpr3tf/J mouse strain exhibits behaviors that align with the major diagnostic criteria of autism. To further evaluate the BTBR strain's cognitive impairments, we quantified hippocampus-dependent object location memory (OLM) and found that one-third of the BTBR mice exhibited robust memory, whereas the remainder did not. Fluorescence deconvolution tomography was used to test whether synaptic levels of activated extracellular signal-regulated kinase 1/2 (ERK1/2), a protein that contributes importantly to plasticity, correlate with OLM scores in individual mice. In hippocampal field CA1, the BTBRs had fewer post-synaptic densities associated with high levels of phosphorylated (p-) ERK1/2 as compared with C57BL/6 mice. Although counts of p-ERK1/2 immunoreactive synapses did not correlate with OLM performance, the intensity of synaptic p-ERK1/2 immunolabeling was negatively correlated with OLM scores across BTBRs. Metabotropic glutamate receptor (mGluR) 5 signaling activates ERK1/2. Therefore, we tested whether treatment with the mGluR5 antagonist MPEP normalizes synaptic and learning measures in BTBR mice: MPEP facilitated OLM and decreased synaptic p-ERK1/2 immunolabeling intensity without affecting numbers of p-ERK1/2+ synapses. In contrast, semi-chronic ampakine treatment, which facilitates memory in other models of cognitive impairment, had no effect on OLM in BTBRs. These results suggest that intellectual disabilities associated with different neurodevelopmental disorders on the autism spectrum require distinct therapeutic strategies based on underlying synaptic pathology. PMID:24448645

  19. Long-term behavior of bituminized waste

    The long-term properties of bituminized ion exchange resins were studied in a repository environment with access of water equilibrated with concrete. In these circumstances the most important properties are related to the interactions of bituminized waste with the surrounding barriers. The most important phenomena are water uptake due to rehydration of the resins and subsequent swelling of the product

  20. NATIONAL LONG TERM CARE SURVEY (NLTCS)

    National Long Term Care Surveys (NLTCS) are surveys of the entire aged population with a particular emphasis on the functionally impaired. Longitudinal study of the health and well-being of elderly Americans. Information about the population of chronically disabled elderly person...

  1. Long-term risks of bisphosphonate therapy

    Nelson B. Watts

    2014-07-01

    Full Text Available The objective this study was to summarize long-term risks associated with bisphosphonate therapy. Search of relevant medical publications for data from clinical trials, trial extensions, observational studies and post-marketing reports. Trial extensions and modifications did not reveal significant long-term safety issues. Observational data suggest at least as many benefits as risks. Post-marketing reports of musculoskeletal pain, osteonecrosis of the jaw and atypical femur fractures have been widely circulated in the lay press. Most focus on long-terms risks has been on osteonecrosis of the jaw and atypical femur fractures which occur in patients who have not received bisphosphonate therapy but may be more frequent (though still uncommon in patients who have been on treatment for 5 years or longer. Lower-risk patients may be able to stop treatment after 3-5 years for a “drug holiday,” which mitigates these long-term risks; for higher risk patients, therapy through 6-10 years appears to be advisable and offers more benefits than risks.

  2. Long-term risks of bisphosphonate therapy.

    Watts, Nelson B

    2014-07-01

    The objective this study was to summarize long-term risks associated with bisphosphonate therapy. Search of relevant medical publications for data from clinical trials, trial extensions, observational studies and post-marketing reports. Trial extensions and modifications did not reveal significant long-term safety issues. Observational data suggest at least as many benefits as risks. Post-marketing reports of musculoskeletal pain, osteonecrosis of the jaw and atypical femur fractures have been widely circulated in the lay press. Most focus on long-terms risks has been on osteonecrosis of the jaw and atypical femur fractures which occur in patients who have not received bisphosphonate therapy but may be more frequent (though still uncommon) in patients who have been on treatment for 5 years or longer. Lower-risk patients may be able to stop treatment after 3-5 years for a "drug holiday," which mitigates these long-term risks; for higher risk patients, therapy through 6-10 years appears to be advisable and offers more benefits than risks. PMID:25166043

  3. Long-term future energy supply

    The paper exposes the long-term future energy supply within a demand side expectation which, though modest, is well in excess of the average 0.75% growth rate of the 1990s. Recent important changes on both the supply and demand sides have created the prospect for a highly sustainable energy future well into the second half of this century

  4. Timber joints under long-term loading

    Feldborg, T.; Johansen, M.

    This report describes tests and results from stiffness and strength testing of splice joints under long-term loading. During two years of loading the spicimens were exposed to cyclically changing relative humidity. After the loading period the specimens were short-term tested. The connectors were...

  5. Hot functional test chemistry - long term experience

    Vonkova, K.; Kysela, J., E-mail: von@ujv.cz [Nuclear Research Inst. Rez plc, Husinec-Rez (Czech Republic); Marcinsky, M. [ENEL-SE, NPP Mochovce, Mochovce (Slovakia); Martykan, M. [CEZ-ETE, NPP Temelin, Temelin (Czech Republic)

    2010-07-01

    Primary circuit materials undergo general corrosion in high temperature, deoxygenated, neutral or mildly alkaline solutions to form thin oxide films. These oxide layers (films) serve as protective film and mitigate the further corrosion of primary materials. Inner chromium-rich oxide layer has low cation diffusion coefficients and thus control iron and nickel transport from the metal surface to the outer layer and their dissolution into the coolant. Much less corrosion products are generated by the compact, integral and stable oxide (passivation) layer. For the latest Czech and Slovak stations commissioned (Temelin and Mochovce) a modified Hot Functional Test (HFT) chemistry was developed in the NRI Rez. Chromium rich surface layer formatted due to modified HTF chemistry ensures lower corrosion rates and radiation field formation and thus also mitigates crud formation during operation. This procedure was also designed to prepare the commissioned unit for the further proper water chemistry practise. Mochovce 1 (SK) was the first station commissioned using these recommendations in 1998. Mochovce 2 (1999) and Temelin 1 and 2 (CZ - 2000 and 2002) were subsequently commissioned using these guidelines too. The main principles of the controlled primary water chemistry applied during the hot functional tests are reviewed and importance of the water chemistry, technological and other relevant parameters is stressed regarding to the quality of the passive layer formed on the primary system surfaces. Samples from Mochovce indicated that duplex oxide layers up to 20 μm thick were produced, which were mainly magnetite substituted with nickel and chromium (e.g. 60-65% Fe, 18-28% Cr, 9-12% Ni, <1% Mn and 1-2% Si on a stainless steel primary circuit sample). Long term operation experience from both nuclear power plants are discussed in this paper. Radiation field, occupational radiation exposure and corrosion layers evolution during the first c. ten years of operation are compared and presented. The operation experience from all above mentioned units showed a low level of corrosion products in the primary system as well as low dose rates. Thus, there is no need for any larger decontamination works. The effect of the initial passivation performed during hot functional tests and the primary water chemistry on the radioactivity level and overall radiation situation of corrosion products is discussed. (author)

  6. Hot functional test chemistry - long term experience

    Primary circuit materials undergo general corrosion in high temperature, deoxygenated, neutral or mildly alkaline solutions to form thin oxide films. These oxide layers (films) serve as protective film and mitigate the further corrosion of primary materials. Inner chromium-rich oxide layer has low cation diffusion coefficients and thus control iron and nickel transport from the metal surface to the outer layer and their dissolution into the coolant. Much less corrosion products are generated by the compact, integral and stable oxide (passivation) layer. For the latest Czech and Slovak stations commissioned (Temelin and Mochovce) a modified Hot Functional Test (HFT) chemistry was developed in the NRI Rez. Chromium rich surface layer formatted due to modified HTF chemistry ensures lower corrosion rates and radiation field formation and thus also mitigates crud formation during operation. This procedure was also designed to prepare the commissioned unit for the further proper water chemistry practise. Mochovce 1 (SK) was the first station commissioned using these recommendations in 1998. Mochovce 2 (1999) and Temelin 1 and 2 (CZ - 2000 and 2002) were subsequently commissioned using these guidelines too. The main principles of the controlled primary water chemistry applied during the hot functional tests are reviewed and importance of the water chemistry, technological and other relevant parameters is stressed regarding to the quality of the passive layer formed on the primary system surfaces. Samples from Mochovce indicated that duplex oxide layers up to 20 μm thick were produced, which were mainly magnetite substituted with nickel and chromium (e.g. 60-65% Fe, 18-28% Cr, 9-12% Ni, <1% Mn and 1-2% Si on a stainless steel primary circuit sample). Long term operation experience from both nuclear power plants are discussed in this paper. Radiation field, occupational radiation exposure and corrosion layers evolution during the first c. ten years of operation are compared and presented. The operation experience from all above mentioned units showed a low level of corrosion products in the primary system as well as low dose rates. Thus, there is no need for any larger decontamination works. The effect of the initial passivation performed during hot functional tests and the primary water chemistry on the radioactivity level and overall radiation situation of corrosion products is discussed. (author)

  7. Synapse Specificity of Long-Term Potentiation Breaks Down with Aging

    Ris, Laurence; Godaux, Emile

    2007-01-01

    Memory shows age-related decline. According to the current prevailing theoretical model, encoding of memories relies on modifications in the strength of the synapses connecting the different cells within a neuronal network. The selective increases in synaptic weight are thought to be biologically implemented by long-term potentiation (LTP). Here,…

  8. Improving students' long-term knowledge retention through personalized review.

    Lindsey, Robert V; Shroyer, Jeffery D; Pashler, Harold; Mozer, Michael C

    2014-03-01

    Human memory is imperfect; thus, periodic review is required for the long-term preservation of knowledge and skills. However, students at every educational level are challenged by an ever-growing amount of material to review and an ongoing imperative to master new material. We developed a method for efficient, systematic, personalized review that combines statistical techniques for inferring individual differences with a psychological theory of memory. The method was integrated into a semester-long middle-school foreign-language course via retrieval-practice software. Using a cumulative exam administered after the semester's end, we compared time-matched review strategies and found that personalized review yielded a 16.5% boost in course retention over current educational practice (massed study) and a 10.0% improvement over a one-size-fits-all strategy for spaced study. PMID:24444515

  9. Electric field modulation of long-term plastic effects

    Belen Lafon

    2012-06-01

    Full Text Available Transcranial electrical stimulation in humans can lead to electric fields of at most 1V/m on the cortical surface. This may polarize cell membranes by a fraction of a milivolt. While these intensities seem very small, there are a number of in vitro experiments explaining the basic mechanisms by which such low-amplitude electric fields may nevertheless acutely alter neuronal activity, both at the single cell and at the network level . However, the long-term plastic effects which have been repeatedly observed clinically are less understood. Here we are particularly interested in the effects of slow-oscillating stimulation during sleep which were shown to boost the consolidation of hippocampus-dependent declarative memory. How synaptic connections are modified resulting in a memory improvement is still unknown. Currently, two main complementary hypotheses exist regarding consolidation of memory during sleep. The synaptic homeostasis hypothesis conjunctures that consolidation is in part a result of synaptic downscaling that improves the signal-to-noise ratio for all synapses that were potentiated during prior waking experiences. The active system consolidation hypothesis proposes an active consolidation process where learning-specific synaptic connections are strengthened by means of increased plasticity-related immediate early gene transcription and induction of LTP. Slow-oscillating stimulation might be improving memory consolidation by means of modulating synaptic downscaling and/or learning-specific synaptic connections. Current results of our group show that this low-amplitude fields induced an effect on the homeostatic downscaling of endogenous slow-waves during sleep. However, the modulation LTP processes related to the potentiation of learning related synapses has not yet been studied for such fields. Previous studies show that electrical stimulation coupled with ongoing activity in the brain induces plasticity, here we will focus on the modulation of LTP processes while applying acutely several low-amplitude field configurations. Thus linking the long-term behavioral effects with acute electrical stimulation.

  10. Chronic pain and other sequelae in long-term breast cancer survivors

    Peuckmann, Vera Irina; Ekholm, Ola; Rasmussen, N K; Groenvold, M; Christiansen, P; Møller, S; Eriksen, J; Sjøgren, P

    2009-01-01

    To investigate self-reported chronic pain and other sequelae in a nationally representative sample of long-term breast cancer survivors (BCS).......To investigate self-reported chronic pain and other sequelae in a nationally representative sample of long-term breast cancer survivors (BCS)....

  11. Quantifying Long-term Scientific Impact

    Wang, Dashun; Barabási, Albert-László

    2013-01-01

    An ability to accurately assess the long-term impact of a scientific discovery has implications from science policy to individual reward. Yet, the documented lack of predictability of citation based measures frequently used to gauge impact, from impact factors to short-term citations, raises a fundamental question: is there long-term predictability in citation patterns? Here we derive a mechanistic model for the citation dynamics of individual papers, allowing us to collapse the citation histories of papers from different journals and disciplines into a single curve, indicating that all papers follow the same universal temporal pattern. The observed patterns not only help us uncover the basic mechanisms that govern scientific impact, but also offer reliable measures of influence with potential policy implications.

  12. Analysis of long-term energy scenarios

    Lemming, J.; Morthorst, P.E.

    1998-09-01

    When addressing the role of fusion energy in the 21. century, the evaluation of possible future structures in the electricity market and the energy sector as a whole, can be a useful tool. Because fusion energy still needs demonstration, commercialized fusion energy is not likely to be a reality within the next few decades. Therefore long-term scenarios are needed describing the energy markets, which fusion energy eventually will be part of. This report performs an analysis of two of the most detailed existing long-term scenarios describing possible futures of the energy system. The aim is to clarify the frames in which the future development of the global energy demand, as well as the structure of the energy system can be expected to develop towards the year 2100. (au) 19 refs.

  13. Long-term selenium status in humans

    The association of sub-optimal selenium status with increased risk factors for some cancers has been reported in two recent epidemiological studies. In both studies the same threshold in selenium status was observed, below which, cancer incidence increased. To assess the use of nails as a biologic monitor to measure the long-term selenium status, an eight-year longitudinal study was undertaken with a group of 11 adult subjects, 5 women and 6 men. Selenium has been measured by instrumental neutron activation analysis. Differences between fingernails and toenails with be discussed. In addition, the results will be discussed in the context of the long-term stability of the nail monitor to measure selenium status during those periods when selenium determinants are static; and the changes that occur as a result of selenium supplementation. (author)

  14. Long-term depression of nociception and pain in healthy volunteers

    Rottmann, Silke

    2010-01-01

    Synaptic plasticity, including long-term potentiation (LTP) and long-term depression (LTD), represents a cellular model of learning and memory. LTP, a long-lasting increase of synaptic strength, can be induced by electrical stimulation with a high frequency. Low-frequency stimulation (LFS) leads to a decrease of synaptic transmission referred to as LTD. Synaptic plasticity was shown in the nociceptive system. LTP is suggested to be involved in central sensitization of pain, leading to a so-ca...

  15. Transcriptional analysis of a whole-body form of long-term habituation in Aplysia californica

    Holmes, Geraldine; Herdegen, Samantha; Schuon, Jonathan; Cyriac, Ashly; Lass, Jamie; Conte, Catherine; Calin-Jageman, Irina E.; Calin-Jageman, Robert J.

    2015-01-01

    Habituation is the simplest form of learning, but we know little about the transcriptional mechanisms that encode long-term habituation memory. A key obstacle is that habituation is relatively stimulus-specific and is thus encoded in small sets of neurons, providing poor signal/noise ratios for transcriptional analysis. To overcome this obstacle, we have developed a protocol for producing whole-body long-term habituation of the siphon-withdrawal reflex (SWR) of Aplysia californica. Specifical...

  16. Long-Term Care, Altruism and Socialization

    Ponthière, Grégory

    2011-01-01

    The public provision of long-term care (LTC) can replace family-provided LTC when adults are not sufficiently altruistic towards their elderly parents. But State intervention can also modify the transmission of values and reduce the long-run prevalence of family altruism in the population. That evolutionary effect questions the desirability of the LTC public provision. To characterize the optimal LTC policy, we develop a three-period OLG model where the population is divided into altruistic a...

  17. Change Management of Long Term Composed Services

    Liu, Xumin

    2009-01-01

    We propose a framework for managing changes in Long term Composed Services (LCSs). The key components of the proposed framework include a Web Service Change Management Language (SCML), change enactment, and change optimization. The SCML is a formal language to specify top-down changes. It is built upon a formal model which consists of a Web service ontology and a LCS schema. The Web service ontology gives a semantic description on the important features of a service, including functionality, ...

  18. Long-term Treatment in Multiple Sclerosis

    Derya ULUDÜZ

    2008-05-01

    Full Text Available Multiple sclerosis is a chronic neuro-inflammatory and neuro-degenerative disease of the CNS which may present and progress heterogeneously. It is rather a spectrum and currently there is some evidence that long term treatments may be effective for its relapsing forms. Such treatments have been shown to reduce the number of attacks and MRI-related disease burden with the probability to slow progression. These long term treatments are considered to have mostly an anti-inflammatory activity. Interferon beta group drugs and glatiramer acetate are likely to exert their therapeutic effects through a number of different mechanisms but probably the main one is anti-inflammatory being through such mechanisms, but their efficacy is limited. Immunosuppressive drugs such as Mitoxantrone and Cyclophosphamide are accepted to have a more potent anti-inflammatory effect with better efficacy, but with more serious adverse effects. Natalizumab is one of the new players in the field with a supposedly better efficacy than the interferon betas or glatiramer acetate, but yet carries an increased risk of being associated with progressive mulifocal leukoencepalopathy as a serious side effect. As not all patients with MS progress and end up with disability, long-term treatments may not be necessary for every individual, who receives the diagnosis of MS. It is the MS neurologist who should consider first whether the patient should be put on long term treatment and once such a decision is given, then which one. The agents to be selected should be determined according to the benefit-risk ratio for each patient individually. In this review these issues are discussed. (Archives of Neuropsychiatry 2008; 45 Supplement: 26-36

  19. Long term evolution 4G and beyond

    Yacoub, Michel; Figueiredo, Fabrício; Tronco, Tania

    2016-01-01

    This book focus on Long Term Evolution (LTE) and beyond. The chapters describe different aspects of research and development in LTE, LTE-Advanced (4G systems) and LTE-450 MHz such as telecommunications regulatory framework, voice over LTE, link adaptation, power control, interference mitigation mechanisms, performance evaluation for different types of antennas, cognitive mesh network, integration of LTE network and satellite, test environment, power amplifiers and so on. It is useful for researchers in the field of mobile communications.

  20. Energy: solutions for the long term

    'Power towers' operated by sunlight, vertical-axis, windmills capable of generating electricity, breeder reactors producing more uranium than they consume, and power plants fuelled by nuclear fusion - these are some of the exotic energy sources to be created as long term alternatives under the U.S. Government's plan for energy and research development. International co-operation, which has already begun, could permit other nations to share with America the fruits of this investment in the future

  1. Long-term reductions in tinnitus severity

    Folmer Robert L

    2002-01-01

    Abstract Background This study was undertaken to assess long-term changes in tinnitus severity exhibited by patients who completed a comprehensive tinnitus management program; to identify factors that contributed to changes in tinnitus severity within this population; to contribute to the development and refinement of effective assessment and management procedures for tinnitus. Methods Detailed questionnaires were mailed to 300 consecutive patients prior to their initial appointment at the Or...

  2. Long-Term Trends in World Politics

    George Modelski

    2015-08-01

    Full Text Available A revisit, and an extension, of the paper “From Leadership to Organization: The Evolution of Global Politics,” originally presented at the University of Zurich in 1993. Three long-term processes: the evolution of global politics (or political globalization; the rise and decline of world powers (the long cycle of global politics; and the emergence of the world system, have been reviewed and updated.

  3. Long term nuclear programme for Australia

    While it is difficult at this time to foreshadow a long term nuclear programme for Australia, the essential ingredients of the decision-making back-ground have been set out. The first involvement in the nuclear scene appears to be an entry as a uranium supplier in the late 1970s, though no indigenous use of uranium as a fuel is foreseen until after 1990. (J.R.)

  4. Long-term consequences of anorexia nervosa.

    Meczekalski, Blazej; Podfigurna-Stopa, Agnieszka; Katulski, Krzysztof

    2013-07-01

    Anorexia nervosa (AN) is a psychiatric disorder that occurs mainly in female adolescents and young women. The obsessive fear of weight gain, critically limited food intake and neuroendocrine aberrations characteristic of AN have both short- and long-term consequences for the reproductive, cardiovascular, gastrointestinal and skeletal systems. Neuroendocrine changes include impairment of gonadotropin releasing-hormone (GnRH) pulsatile secretion and changes in neuropeptide activity at the hypothalamic level, which cause profound hypoestrogenism. AN is related to a decrease in bone mass density, which can lead to osteopenia and osteoporosis and a significant increase in fracture risk in later life. Rates of birth complications and low birth weight may be higher in women with previous AN. The condition is associated with fertility problems, unplanned pregnancies and generally negative attitudes to pregnancy. During pregnancy, women with the condition have higher rates of hyperemesis gravidarum, anaemia and obstetric complications, as well as impaired weight gain and compromised intrauterine foetal growth. It is reported that 80% of AN patients are affected by a cardiac complications such as sinus bradycardia, a prolonged QT interval on electrocardiography, arrythmias, myocardial mass modification and hypotension. A decrease in bone mineral density (BMD) is one of the most important medical consequences of AN. Reduced BMD may subsequently lead to a three- to seven-fold increased risk of spontaneous fractures. Untreated AN is associated with a significant increase in the risk of death. Better detection and sophisticated therapy should prevent the long-term consequences of this disorder. The aims of treatment are not only recovery but also prophylaxis and relief of the long-term effects of this disorder. Further investigations of the long-term disease risk are needed. PMID:23706279

  5. Long-term course of opioid addiction.

    Hser, Yih-Ing; Evans, Elizabeth; Grella, Christine; Ling, Walter; Anglin, Douglas

    2015-01-01

    Opioid addiction is associated with excess mortality, morbidities, and other adverse conditions. Guided by a life-course framework, we review the literature on the long-term course of opioid addiction in terms of use trajectories, transitions, and turning points, as well as other factors that facilitate recovery from addiction. Most long-term follow-up studies are based on heroin addicts recruited from treatment settings (mostly methadone maintenance treatment), many of whom are referred by the criminal justice system. Cumulative evidence indicates that opioid addiction is a chronic disorder with frequent relapses. Longer treatment retention is associated with a greater likelihood of abstinence, whereas incarceration is negatively related to subsequent abstinence. Over the long term, the mortality rate of opioid addicts (overdose being the most common cause) is about 6 to 20 times greater than that of the general population; among those who remain alive, the prevalence of stable abstinence from opioid use is low (less than 30% after 10-30 years of observation), and many continue to use alcohol and other drugs after ceasing to use opioids. Histories of sexual or physical abuse and comorbid mental disorders are associated with the persistence of opioid use, whereas family and social support, as well as employment, facilitates recovery. Maintaining opioid abstinence for at least five years substantially increases the likelihood of future stable abstinence. Recent advances in pharmacological treatment options (buprenorphine and naltrexone) include depot formulations offering longer duration of medication; their impact on the long-term course of opioid addiction remains to be assessed. PMID:25747921

  6. Long Term Evolution of Plasma Wakefields

    Sahai, Aakash A.; Katsouleas, T. C.; Tsung, F. S.; Mori, W.B.

    2014-01-01

    We study the long-term evolution (LTE) of plasma wakefields over multiple plasma-electron periods and few plasma-ion periods, much less than a recombination time. The evolution and relaxation of such a wakefield-perturbed plasma over these timescales has important implications for the upper limits of repetition-rates in plasma colliders. Intense fields in relativistic lasers (or intense beams) create plasma wakefields (modes around {\\omega}pe) by transferring energy to the plasma electrons. C...

  7. Endogenous altruism, redistribution, and long term care

    Helmuth CREMER; Gahvari, Firouz; Pestieau, Pierre

    2013-01-01

    This paper studies public provision of long term care insurance in a world in which family assistance is (i) uncertain and (ii) endogenous depending on the time parents spend raising their children. Public benefits will be paid in case of disability but cannot be combined with self-insurance or family aid. The benefits are provided equally to all recipients and financed by a proportional payroll tax. The paper shows that tax distortions imply that full insurance is undesirable. It characteriz...

  8. Motivational readiness for physical activity and quality of life in long-term lung cancer survivors

    Clark, Matthew M.; Novotny, Paul J.; Patten, Christi A.; Rausch, Sarah M.; Garces, Yolanda I.; Jatoi, Aminah; Sloan, Jeff A; Yang, Ping

    2008-01-01

    Little is known about the relationship between motivational readiness for physical activity and quality of life (QOL) in long-term lung cancer survivors. Long-term survivors are considered those who are living 5 years or more following a cancer diagnosis. This project examined the relationship between a self-report measure of motivational readiness for physical activity and QOL in a sample of 272 long-term lung cancer survivors. Participants (54% male, average age 70 years old) completed the ...

  9. Long term culture and characterization of chicken primordial germ cells

    Tonus, Céline; Waroux, Olivier; Cloquette, Karine; Ectors, Fabien; Piret, Joëlle; Antoine, Nadine; Grobet, Luc

    2012-01-01

    Avian primordial germ cells (PGCs), can keep their germ cells properties and are foreseen as promising tools for developing avian transgenesis and preservation of genetic resources of endangered species. We have developed original methods that allow long term (20 month) expansion of primary cultures of undifferentiated PGCs and their efficient cryopreservation. Blood samples were collected from stage 13-18 embryos, pooled, deposited in cell culture inserts and co-cultivated in the presenc...

  10. Public vs private demand for covering long term care expenditures

    Brau, Rinaldo; Lippi Bruni, Matteo; Pinna, Anna Maria

    2009-01-01

    This paper studies the determinants of the willingness to pay (WTP) for long term care (LTC) coverage provided through either a public or a private insurance program. Two insurance services are considered, a first one compulsory and financed out through general taxes, another one purchased on a voluntary base and paid through an insurance premium. Data are taken from a survey on a sample of households of the Italian region Emilia Romagna, and WTP is elicited through open-ended contingent valu...

  11. An event history analysis on German long-term unemployment

    Linzert, Tobias

    2000-01-01

    This paper investigates the determinants of German long-term unemployment. In particular a microeconometric event history analysis will be carried out to examine what impact personal characteristics such as age, gender, education, etc. or factors such as receiving unemployment benefits have on the length of unemployment. The paper further discusses the advantages and disadvantages of a semi-parametric and a parametric estimate of the sample. The use of the Cox model on the one hand and a Weib...

  12. Data of long term atmospheric diffusion experiments (Winter, 1992)

    Hayashi, Takashi; Chino, Masamichi; Yamazawa, Hiromi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    1998-10-01

    The data were obtained in the long-term atmospheric diffusion experiments in the Tokai area, autumn, 1991 which were a part of the Evaluation Safety Demonstration Experiments of Environmental Radiation entrusted with the Science and Technology Agency. The experiments were conducted by JAERI in cooperation with the Japan Weather Association. The report includes tracer concentration data of surface sampling points and meteorological data. (author)

  13. Establishment of a cohort for the long-term clinical follow-up with dose reconstruction under the joint medical research project conducted by Sasakawa Memorial Health Foundation (Japan) and the Research Institute of Radiation Hygiene (Russia)

    The cohort of children in the western districts of the Bryansk Region of Russia exposed to radiation following the Chernobyl accident is described in this paper. The cohort was selected under the Joint Medical Research Project on Dosimetry Associated with the Chernobyl Accident conducted by Sasakawa Memorial Health Foundation (SMHF, Japan) and the Research Institute of Radiation Hygiene (RIRH, Russia). The subjects of the Research Project are those people residing in the most contaminated areas of Russia who was 0 to 10 years old at the time of exposure. At the moment the cohort comprises 1210 subjects, though this number may slightly decrease in course of a follow-up in view of migration of population. Most of cohort subjects were examined on their health status within the framework of the Chernobyl Sasakawa Health and Medical Cooperation Project (CSHMCP) from 1991-1996. In view of the main findings of studies in CSHMCP were thyroid abnormalities, selection of subjects was conducted on the basis of the credible estimates of thyroid dose. Preference for subjects to be included into the cohort was defined by the availability of health examination data from previous study (1991-1996) and individual dosimetry, environmental and social data that may prove useful for reconstruction of individual dose. The primary data analyzed for subjects selection are measurements of iodine-131 in the thyroid in May-June 1986, questionnaire data on individual food habits and early measurements of radiocesium in the body of subjects made by RIRH from May to September 1986. Plausible analytical models were applied to calculate thyroid dose from available data. Previously worked out methods of thyroid dose reconstruction using early measurement data of radiocesium content in the body and questionnaire data on individual consumption of locally produced milk were reevaluated. Basing on these analytical procedures, the individual thyroid dose was ascribed to each member of the cohort. The preliminary distribution of internal radiation doses to the thyroid among subjects of the cohort is presented in the paper. The summary characteristics of dose distribution for cohort subjects seems to be reasonably credible, whereas, the individual doses to particular subjects are evaluated with essential degree of uncertainty. The further stage of dose reconstruction for a cohort study, that is now in progress, consists of reduction of these uncertainties by using additional (newly derived) questionnaire information, as well as by taking into account contribution of external radiation to thyroid dose and updating analytical procedures to interpret primary data. Finally, the distribution of subjects into several thyroid dose ranges, from 2 Gy, would be an acceptable approximation for the purposes of radiation epidemiology in a trial to access the radiation risk of developing thyroid diseases. (author)

  14. Heterogeneity in long-term trajectories of depressive symptoms

    Musliner, Katherine L; Munk-Olsen, Trine; Eaton, William W; Zandi, Peter P

    2016-01-01

    BACKGROUND: Evidence suggests that long-term trajectories of depressive symptoms vary greatly throughout the population, with some individuals experiencing few or no symptoms, some experiencing transient symptoms and others experiencing chronic depression. The goal of this paper is to review...... studies that examined heterogeneity in long-term trajectories of depressive symptoms and summarize the current knowledge regarding (a) the number and patterns of trajectories and (b) antecedents and outcomes associated with different trajectory patterns. METHODS: We conducted a systematic review of...... literature in the Medline and PsychINFO databases. Articles were included if they (a) modeled trajectories of depressive symptoms, (b) used a group-based trajectory modeling approach, (c) followed participants for 5+ years and (d) had a sample size of at least 200. RESULTS: We identified 25 studies from 24...

  15. Long-term planetary integration with individual time steps

    Saha, P; Prasenjit Saha; Scott Tremaine

    1994-01-01

    We describe an algorithm for long-term planetary orbit integrations, including the dominant post-Newtonian effects, that employs individual timesteps for each planet. The algorithm is symplectic and exhibits short-term errors that are O(\\epsilon\\Omega^2\\tau^2) where \\tau is the timestep, \\Omega is a typical orbital frequency, and \\epsilon\\ll1 is a typical planetary mass in solar units. By a special starting procedure long-term errors over an integration interval T can be reduced to O(\\epsilon^2\\Omega^3\\tau^2T). A sample 0.8 Myr integration of the nine planets illustrates that Pluto can have a timestep more than 100 times Mercury's, without dominating the positional error. Our algorithm is applicable to other N-body systems.

  16. Health care utilisation among individuals reporting long-term pain

    Eriksen, Jørgen; Sjøgren, Per; Ekholm, Ola; Rasmussen, Niels K

    2004-01-01

    Individuals reporting long-term pain in the 1994 and 2000 Danish Health and Morbidity Surveys, which included random samples of 6000 and 16,684 persons respectively, were investigated concerning their use of the health care systems. A considerably higher use was observed in the pain population in...... the primary as well as the secondary health care sector, compared with a no pain control group. In 1994, individuals reporting long-term pain had on average 12.8 contacts per year to the primary health care sector compared with 7.3 for the control group. Use of secondary health care sector as...... estimated by hospital admission frequency and number of in-hospital days was not only significantly higher for the pain group but showed also an increasing tendency during the periods investigated (1991-1997). Women used the health care system significantly more than men, whereas age did not seem to...

  17. Long-term health benefits of appetite suppressants remain unproven

    Francisco José Roma Paumgartten

    2011-12-01

    Full Text Available Because of the increasing prevalence of obesity, prevention and treatment of overweight has become a major public health concern. In addition to diet and exercise, drugs are needed for patients who failed to lose weight with behavioral treatment. The current article aimed to summarize recent concerns on the safety and efficacy of appetite suppressants. Several appetite suppressants have been banned for safety reasons. In 2010, sibutramine was withdrawn from the market because a long-term study showed it increased the risks of cardiovascular events. So far no study with a sufficiently large sample size has demonstrated that appetite suppressants can reduce morbidity and mortality associated with overweight. The withdrawal of sibutramine highlights that guidelines for the evaluation of weight control drugs must be more stringent, and studies on their long-term health benefits are needed prior to their marketing.

  18. Long Term R&D for Safeguards

    Within the Office of Defense Nuclear Non-proliferation Research and Development (DNN R&D), the Nuclear Weapons and Material Security Team conducts research to develop advanced detection and source technologies for the purposes of detecting and characterizing special nuclear materials (SNM); international safeguards and radiological source replacement; nuclear arms control treaty monitoring and verification; and supporting interdiction and nuclear security efforts across NNSA. Our safeguards-specific goal is to develop and demonstrate new technologies and capabilities to cooperatively quantify and track SNM in the nuclear fuel cycle and detect any diversion of these materials for illicit purposes. Our goals and objectives align with a technology goal of the International Atomic Energy's Long Term Strategy for 2012-2023 ''to improve the Department's technical capabilities by making use of scientific and technological innovation, and to enhance its readiness to safeguard new nuclear technology and support new verification missions.'' Toward that end, we work closely with the US Department of Energy's Next Generation Safeguards Initiative and the US Support Programme to meet their specific long term needs. In this talk we will give a brief overview of current research efforts and specifically describe several helium-3 replacement technologies, advanced spent nuclear fuel characterization methods, and upcoming tags and seals technologies. We will present additional research into cross cutting enabling technologies such as advancements in detector materials, electronics, and sources, and basic physics measurements that support long term safeguards R&D. (author)

  19. Timber beams subjected to long - term loading

    Sógel, K.

    2010-09-01

    Wood is a significant structural material, which is often used for timber bearing structures. Elements of timber structures must especially satisfy safety requirements, which are expressed by the ultimate limit states in the established standards. The structure must also satisfy the serviceability limit states. Local and global deformations make it impossible for the structure to serve the purpose it was designed for. It is important to take the deflections and their possible increase into account in the design to provide a structure which can be used during the whole period of service. Based on earlier examinations, it is known that a timber element over the course of long-term loading shows creep behavior. The structure of wood is able to adapt to the conditions of the surrounding environment. The properties of wood are especially affected by the relative humidity of the air and then by the type, intensity and duration of the loading. The most important factors affecting the serviceability of timber structures are volume changes caused by humidity and additional deflections caused by the effects of long-term loading. These phenomena emphasize the importance of serviceability limit states for timber structures. The paper deals with a long-term experimental investigation of timber girders that are currently often used. The aim was to obtain the deflection curves and mark the time dependence and the final deflections. The paper will also define the approximations for simulating the time-dependent deflections and obtain the creep coefficients for calculating the final deflections of the girders investigated.

  20. Long-term governance for sustainability

    Meritxell Martell spoke of the long-term aspects of radioactive waste management. She pointed out that decision-making processes need to be framed within the context of sustainability, which means that a balance should be sought between scientific considerations, economic aspects and structural conditions. Focusing on structural aspects, Working Group 3 of COWAM-Spain came to the conclusion that the activity of the regulator is a key factor of long-term management. Another finding is that from a sustainability perspective multi-level governance is more effective for coping with the challenges of radioactive waste management than one tier of government-making decisions. The working group also felt that the current Local Information Committees need to evolve towards more institutionalized and legitimized mechanisms for long-term involvement. Ms. Martell introduced a study comparing the efficiency of economic instruments to advance sustainable development in nuclear communities vs. municipalities in mining areas. The study found that funds transferred to nuclear zones had become a means to facilitate local acceptance of nuclear facilities rather than a means to promote socio-economic development. Another finding is that economic instruments are not sufficient guarantees of sustainable development by themselves; additional preconditions include leadership, vision and entrepreneur-ship on the part of community leaders, private or public investments, among others. Finally, Ms. Martell summarised the challenges faced by the Spanish radioactive waste management programme, which include the need for strategic thinking, designing the future in a participatory fashion, and working with local and regional governments and citizens to devise mechanisms for social learning, economic development and environmental protection. (author)