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Sample records for behavioural memory test

  1. [Evaluation of memory in acquired brain injury: a comparison between the Wechsler Memory Scale and the Rivermead Behaviour Memory Test].

    Science.gov (United States)

    Guinea-Hidalgo, A; Luna-Lario, P; Tirapu-Ustárroz, J

    Learning processes and memory are frequently compromised in acquired brain injury (ABI), while at the same time such involvement is often heterogeneous and a source of deficits in other cognitive capacities and significant functional limitations. A good neuropsychological evaluation of memory is designed to study not only the type, intensity and nature of the problems, but also the way they manifest in daily life. This study examines the correlation between a traditional memory test, the Wechsler Memory Scale-III (WMS-III), and a memory test that is considered to be functional, the Rivermead Behavioural Memory Test (RBMT), in a sample of 60 patients with ABI. All the correlations that were observed were moderate. Greater correlations were found among the verbal memory subtests than among the visual memory tests. An important number of subjects with below-normal scalar scores on the WMS-III correctly performed (either fully or partially) the corresponding test in the RBMT. The joint use of the WMS-III and RBMT in evaluation can provide a more comprehensive analysis of the memory deficits and their rehabilitation. The lower scores obtained in the WMS-III compared to those of the RBMT indicate greater sensitivity of the former. Nevertheless, further testing needs to be carried out in the future to compare the performance in the tests after the patients and those around them have subjectively assessed their functional limitations. This would make it possible to determine which of the two tests offers the best balance between sensitivity and specificity, as well as a higher predictive value.

  2. Detection of memory impairment among community-dwelling elderly by using the Rivermead Behavioural Memory Test

    International Nuclear Information System (INIS)

    Shinagawa, Shunichiro; Toyota, Yasutaka; Matsumoto, Teruhisa; Sonobe, Naomi; Adachi, Hiroyoshi; Mori, Takaaki; Ishikawa, Tomohisa; Fukuhara, Ryuji; Ikeda, Manabu

    2010-01-01

    The aim of this study was to use the Rivermead Behavioural Memory Test (RBMT) to evaluate everyday memory impairment among community-dwelling elderly who had normal cognitive function and performed daily activities normally but displayed memory impairments, and to diagnose the condition as either mild cognitive impairment or dementia. Among the 1,290 community-dwelling elderly persons who participated in the study, 72 subjects scored higher than 24 on the Mini-Mental State Examination (MMSE): these subjects performed daily activities normally, but their family members reported that they showed memory impairments. Fifty-two subjects completed RBMT, Clinical Dementia Rating, and brain computed tomography, and a final diagnosis was established. The mean standard profile score was 15.1±5.0 and mean screening score was 6.4±3.0. RBMT score was correlated with the MMSE score. Nine of the subjects were diagnosed with dementia and 26 of them were found to be normal. RBMT achieved 100% sensitivity and specificity with regard to the differentiation of subjects with Alzheimer's disease. However, some subjects were diagnosed with dementia even though their RBMT score was higher than the cut-off score. RBMT was useful in detecting memory impairments of Alzheimer's disease (AD) subjects in community-based surveys. However, some subjects were diagnosed with dementia because of the existence of other cognitive impairments among community-dwelling elderly. (author)

  3. Ecological assessment of mild cognitive impairment and Alzheimer disease using the Rivermead Behavioural Memory Test.

    Science.gov (United States)

    Bolló-Gasol, S; Piñol-Ripoll, G; Cejudo-Bolivar, J C; Llorente-Vizcaino, A; Peraita-Adrados, H

    2014-01-01

    The Rivermead Behavioural Memory Test (RBMT) is a short, ecologically-valid memory test battery that can provide data about a subject's memory function in daily life. We used RBMT to examine daily memory function in patients with mild cognitive impairment (MCI), Alzheimer disease (AD), and in healthy controls. We also evaluated differences between the memory profiles of subjects whose MCI remained stable after 1 year and those with conversion to AD. Sample of 91 subjects older than 60 years: 30 controls, 27 MCI subjects and 34 AD patients. Subjects were assessed using MMSE and RBMT. The 40 men and 51 women in the sample had a mean age of 74.29±6.71 and 5.87±2.93 years of education. For the total profile and screening RBMT scores (Pde Neurología. Published by Elsevier Espana. All rights reserved.

  4. Applicability of the Rivermead Behavioural Memory Test - Third Edition (RBMT-3) in Korsakoff's syndrome and chronic alcoholics

    NARCIS (Netherlands)

    Wester, A.J.; Herten, J.C. van; Egger, J.I.M.; Kessels, R.P.C.

    2013-01-01

    Purpose: To examine the applicability of the newly developed Rivermead Behavioural Memory Test – Third Edition (RBMT-3) as an ecologically-valid memory test in patients with alcohol-related cognitive disorders. Patients and methods: An authorized Dutch translation of the RBMT-3 was developed,

  5. Applicability of the Rivermead Behavioural Memory Test - Third Edition (RBMT-3) in Korsakoff's syndrome and chronic alcoholics

    NARCIS (Netherlands)

    Wester, A.J.; Herten, J.C. van; Egger, J.I.; Kessels, R.P.C.

    2013-01-01

    PURPOSE: To examine the applicability of the newly developed Rivermead Behavioural Memory Test - Third Edition (RBMT-3) as an ecologically-valid memory test in patients with alcohol-related cognitive disorders. PATIENTS AND METHODS: An authorized Dutch translation of the RBMT-3 was developed,

  6. Advances in the behavioural testing and network imaging of rodent recognition memory

    Science.gov (United States)

    Kinnavane, Lisa; Albasser, Mathieu M.; Aggleton, John P.

    2015-01-01

    Research into object recognition memory has been galvanised by the introduction of spontaneous preference tests for rodents. The standard task, however, contains a number of inherent shortcomings that reduce its power. Particular issues include the problem that individual trials are time consuming, so limiting the total number of trials in any condition. In addition, the spontaneous nature of the behaviour and the variability between test objects add unwanted noise. To combat these issues, the ‘bow-tie maze’ was introduced. Although still based on the spontaneous preference of novel over familiar stimuli, the ability to give multiple trials within a session without handling the rodents, as well as using the same objects as both novel and familiar samples on different trials, overcomes key limitations in the standard task. Giving multiple trials within a single session also creates new opportunities for functional imaging of object recognition memory. A series of studies are described that examine the expression of the immediate-early gene, c-fos. Object recognition memory is associated with increases in perirhinal cortex and area Te2 c-fos activity. When rats explore novel objects the pathway from the perirhinal cortex to lateral entorhinal cortex, and then to the dentate gyrus and CA3, is engaged. In contrast, when familiar objects are explored the pathway from the perirhinal cortex to lateral entorhinal cortex, and then to CA1, takes precedence. The switch to the perforant pathway (novel stimuli) from the temporoammonic pathway (familiar stimuli) may assist the enhanced associative learning promoted by novel stimuli. PMID:25106740

  7. Advances in the behavioural testing and network imaging of rodent recognition memory.

    Science.gov (United States)

    Kinnavane, Lisa; Albasser, Mathieu M; Aggleton, John P

    2015-05-15

    Research into object recognition memory has been galvanised by the introduction of spontaneous preference tests for rodents. The standard task, however, contains a number of inherent shortcomings that reduce its power. Particular issues include the problem that individual trials are time consuming, so limiting the total number of trials in any condition. In addition, the spontaneous nature of the behaviour and the variability between test objects add unwanted noise. To combat these issues, the 'bow-tie maze' was introduced. Although still based on the spontaneous preference of novel over familiar stimuli, the ability to give multiple trials within a session without handling the rodents, as well as using the same objects as both novel and familiar samples on different trials, overcomes key limitations in the standard task. Giving multiple trials within a single session also creates new opportunities for functional imaging of object recognition memory. A series of studies are described that examine the expression of the immediate-early gene, c-fos. Object recognition memory is associated with increases in perirhinal cortex and area Te2 c-fos activity. When rats explore novel objects the pathway from the perirhinal cortex to lateral entorhinal cortex, and then to the dentate gyrus and CA3, is engaged. In contrast, when familiar objects are explored the pathway from the perirhinal cortex to lateral entorhinal cortex, and then to CA1, takes precedence. The switch to the perforant pathway (novel stimuli) from the temporoammonic pathway (familiar stimuli) may assist the enhanced associative learning promoted by novel stimuli. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Magnetic shape memory behaviour

    International Nuclear Information System (INIS)

    Brown, P.J.; Gandy, A.P.; Ishida, K.; Kainuma, R.; Kanomata, T.; Matsumoto, M.; Morito, H.; Neumann, K.-U.; Oikawa, K.; Ouladdiaf, B.; Ziebeck, K.R.A.

    2007-01-01

    Materials that can be transformed at one temperature T F , then cooled to a lower temperature T M and plastically deformed and on heating to T F regain their original shape are currently receiving considerable attention. In recovering their shape the alloys can produce a displacement or a force, or a combination of the two. Such behaviour is known as the shape memory effect and usually takes place by change of temperature or applied stress. For many applications the transformation is not sufficiently rapid or a change in temperature/pressure not appropriate. As a result, considerable effort is being made to find a ferromagnetic system in which the effect can be controlled by an applied magnetic field. The results of recent experiments on ferromagnetic shape memory compounds aimed at understanding the underlying mechanism will be reviewed

  9. Applicability of the Rivermead Behavioural Memory Test – Third Edition (RBMT-3) in Korsakoff’s syndrome and chronic alcoholics

    Science.gov (United States)

    Wester, Arie J; van Herten, Judith C; Egger, Jos IM; Kessels, Roy PC

    2013-01-01

    Purpose To examine the applicability of the newly developed Rivermead Behavioural Memory Test – Third Edition (RBMT-3) as an ecologically-valid memory test in patients with alcohol-related cognitive disorders. Patients and methods An authorized Dutch translation of the RBMT-3 was developed, equivalent to the UK version, and administered to a total of 151 participants – 49 patients with amnesia due to alcoholic Korsakoff’s syndrome, 49 patients with cognitive impairment and a history of chronic alcoholism, not fulfilling the Korsakoff criteria, and 53 healthy controls. Between-group comparisons were made at subtest level, and the test’s diagnostic accuracy was determined. Results Korsakoff patients performed worse than controls on all RBMT-3 subtests (all P-values Korsakoff patients and the controls after delayed testing. The RBMT-3 had good sensitivity and adequate specificity. Conclusion The RBMT-3 is a valid test battery to demonstrate everyday memory deficits in Korsakoff patients and non-Korsakoff patients with alcohol abuse disorder. Korsakoff patients showed an impaired performance on subtests relying on orientation, contextual memory and delayed testing. Our findings provide valuable information for treatment planning and adjustment in patients with alcohol-related cognitive impairments. PMID:23818787

  10. Assessment of Alcohol-related Memory Deficits: A Comparison between the Rivermead Behavioural Memory Test and the California Verbal Learning Test

    NARCIS (Netherlands)

    Wester, A.J.; Roelofs, R.L.; Egger, J.I.M.; Kessels, R.P.C.

    2014-01-01

    Objectives: Neuropsychological assessment of memory disorders is an important prerequisite in the treatment of patients with alcohol-related cognitive disorders. Although many memory tests are available in clinical practice, a question remains regarding which test is most appropriate for this

  11. Applicability of the Rivermead Behavioural Memory Test – Third Edition (RBMT-3 in Korsakoff's syndrome and chronic alcoholics

    Directory of Open Access Journals (Sweden)

    Wester AJ

    2013-06-01

    Full Text Available Arie J Wester,1 Judith C van Herten,2 Jos IM Egger,2–4 Roy PC Kessels1,2,5 1Korsakoff Clinic, Vincent van Gogh Institute for Psychiatry, Venray, The Netherlands; 2Donders Institute for Brain, Cognition and Behavior, Radboud University Nijmegen, Nijmegen, The Netherlands; 3Centre of Excellence for Neuropsychiatry, Vincent van Gogh Institute for Psychiatry, Venray, The Netherlands; 4Behavioral Science Institute, Radboud University Nijmegen, Nijmegen, The Netherlands; 5Department of Medical Psychology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands Purpose: To examine the applicability of the newly developed Rivermead Behavioural Memory Test – Third Edition (RBMT-3 as an ecologically-valid memory test in patients with alcohol-related cognitive disorders. Patients and methods: An authorized Dutch translation of the RBMT-3 was developed, equivalent to the UK version, and administered to a total of 151 participants – 49 patients with amnesia due to alcoholic Korsakoff's syndrome, 49 patients with cognitive impairment and a history of chronic alcoholism, not fulfilling the Korsakoff criteria, and 53 healthy controls. Between-group comparisons were made at subtest level, and the test's diagnostic accuracy was determined. Results: Korsakoff patients performed worse than controls on all RBMT-3 subtests (all P-values < 0.0005. The alcoholism group performed worse than controls on most (all P-values < 0.02, but not all RBMT-3 subtests. Largest effects were found between the Korsakoff patients and the controls after delayed testing. The RBMT-3 had good sensitivity and adequate specificity. Conclusion: The RBMT-3 is a valid test battery to demonstrate everyday memory deficits in Korsakoff patients and non-Korsakoff patients with alcohol abuse disorder. Korsakoff patients showed an impaired performance on subtests relying on orientation, contextual memory and delayed testing. Our findings provide valuable information for treatment

  12. Behavioural memory reconsolidation of food and fear memories.

    Science.gov (United States)

    Flavell, Charlotte R; Barber, David J; Lee, Jonathan L C

    2011-10-18

    The reactivation of a memory through retrieval can render it subject to disruption or modification through the process of memory reconsolidation. In both humans and rodents, briefly reactivating a fear memory results in effective erasure by subsequent extinction training. Here we show that a similar strategy is equally effective in the disruption of appetitive pavlovian cue-food memories. However, systemic administration of the NMDA receptor partial agonist D-cycloserine, under the same behavioural conditions, did not potentiate appetitive memory extinction, suggesting that reactivation does not enhance subsequent extinction learning. To confirm that reactivation followed by extinction reflects a behavioural analogue of memory reconsolidation, we show that prevention of contextual fear memory reactivation by the L-type voltage-gated calcium channel blocker nimodipine interferes with the amnestic outcome. Therefore, the reconsolidation process can be manipulated behaviourally to disrupt both aversive and appetitive memories. © 2011 Macmillan Publishers Limited. All rights reserved.

  13. Attentional and Executive Function Behaviours in Children with Poor Working Memory

    Science.gov (United States)

    Gathercole, Susan E.; Alloway, Tracy P.; Kirkwood, Hannah J.; Elliott, Julian G.; Holmes, Joni; Hilton, Kerry A.

    2008-01-01

    The purpose of this study was to explore the profiles of classroom behaviour relating to attention and executive functions in children with very poor working memory, and to test the hypothesis that inattentive behaviour and working memory problems co-occur. Teachers rated problem behaviours of 52 children with low working memory scores aged 5/6…

  14. [Memory Checking Tests].

    Science.gov (United States)

    Hart, Joseph T.

    Two basic tests for checking memory skills are included in these appendices. The first, the General Information Test, uses the same 150 items for each of its two versions. One version is a completion-type test which measures recall by requiring the examinee to supply a specific response. The other version supplements each of the 150 items with…

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

    Science.gov (United States)

    Biondolillo, Mathew J; Pillemer, David B

    2015-01-01

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

  16. Testing Mechanisms for Philanthropic Behaviour

    NARCIS (Netherlands)

    Bekkers, R.H.F.P.; Wiepking, P.

    2011-01-01

    This special issue of the International Journal of Nonprofit and Voluntary Sector Marketing presents a collection of nine papers testing mechanisms that drive philanthropic behaviour. By testing one or more specific mechanisms that were derived from the philanthropic literature, the authors of the

  17. Teachers' Perceptions of Classroom Behaviour and Working Memory

    Science.gov (United States)

    Alloway, Tracy Packiam

    2012-01-01

    Working memory, ability to remember and manipulate information, is crucial to academic attainment. The aim of the present study was to understand teachers' perception of working memory and how it impacts classroom behaviour. A semi-structured interview was used to explore teachers' ability to define working memory, identify these difficulties in…

  18. Self-Testing Computer Memory

    Science.gov (United States)

    Chau, Savio, N.; Rennels, David A.

    1988-01-01

    Memory system for computer repeatedly tests itself during brief, regular interruptions of normal processing of data. Detects and corrects transient faults as single-event upsets (changes in bits due to ionizing radiation) within milliseconds after occuring. Self-testing concept surpasses conventional by actively flushing latent defects out of memory and attempting to correct before accumulating beyond capacity for self-correction or detection. Cost of improvement modest increase in complexity of circuitry and operating time.

  19. Working Memory, Cognitive Style, and Behavioural Predictors of GCSE Exam Success

    Science.gov (United States)

    Grimley, Michael; Banner, Gloria

    2008-01-01

    This study investigates the interplay of working memory, cognitive style, and behaviour. Year 8 (aged 13 years) students (n = 205) at a UK urban secondary school were tested to ascertain predictors of General Certificate of School Education (GCSE) achievement. Assessment included Riding's cognitive style dimensions, working memory capacity, and a…

  20. Dynamical behaviour of neuronal networks iterated with memory

    International Nuclear Information System (INIS)

    Melatagia, P.M.; Ndoundam, R.; Tchuente, M.

    2005-11-01

    We study memory iteration where the updating consider a longer history of each site and the set of interaction matrices is palindromic. We analyze two different ways of updating the networks: parallel iteration with memory and sequential iteration with memory that we introduce in this paper. For parallel iteration, we define Lyapunov functional which permits us to characterize the periods behaviour and explicitly bounds the transient lengths of neural networks iterated with memory. For sequential iteration, we use an algebraic invariant to characterize the periods behaviour of the studied model of neural computation. (author)

  1. Memory behaviour in a radiation environment

    International Nuclear Information System (INIS)

    Brucker, G.J.; Thurlow, L.

    1979-01-01

    Memory devices are often required for storage of data which must not be altered during a nuclear burst. If the properties of non-alterability and low power consumption during a standby mode of operation are combined, then the choice is narrowed down to static C-MOS bulk or silicon-on-sapphire (SOS) memories. Previous investigations have indicated that the SOS devices will achieve the maximum non-scrambling dose rate. However, it is interesting to determine the limitations of bulk as well as SOS devices for those programs where circumvention and refreshing of the memory is allowed. This article will present the results of an investigation of the characteristics of these memory types in a transient environment. (author)

  2. Memory Tests with Ambient Odours "Make Scents"

    OpenAIRE

    Nord, Marie

    2015-01-01

    An ambient odour of anise was used in a context-dependent memory study with three different memory tasks targeting both declarative and non-declarative memory functions. Declarative memory was assessed by means of two episodic memory tests; recall of a prose text and a complex figure. Priming was used to assess the non-declarative memory with word fragment completion. Memory was tested immediately and after 48 hours. The results showed a significant main effect of context (odour or not) for a...

  3. A revised limbic system model for memory, emotion and behaviour.

    Science.gov (United States)

    Catani, Marco; Dell'acqua, Flavio; Thiebaut de Schotten, Michel

    2013-09-01

    Emotion, memories and behaviour emerge from the coordinated activities of regions connected by the limbic system. Here, we propose an update of the limbic model based on the seminal work of Papez, Yakovlev and MacLean. In the revised model we identify three distinct but partially overlapping networks: (i) the Hippocampal-diencephalic and parahippocampal-retrosplenial network dedicated to memory and spatial orientation; (ii) The temporo-amygdala-orbitofrontal network for the integration of visceral sensation and emotion with semantic memory and behaviour; (iii) the default-mode network involved in autobiographical memories and introspective self-directed thinking. The three networks share cortical nodes that are emerging as principal hubs in connectomic analysis. This revised network model of the limbic system reconciles recent functional imaging findings with anatomical accounts of clinical disorders commonly associated with limbic pathology. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Behavioural Models of Motor Control and Short-Term Memory

    OpenAIRE

    Imanaka, Kuniyasu; Funase, Kozo; Yamauchi, Masaki

    1995-01-01

    We examined in this review article the behavioural and conceptual models of motor control and short-term memory which have intensively been investigated since the 1970s. First, we reviewed both the dual-storage model of short-term memory in which movement information is stored and a typical model of motor control which emphasizes the importance of efferent factors. We then examined two models of preselection effects: a cognitive model and a cognitive/ efferent model. Following this we reviewe...

  5. Accelerated behavioural development changes fine-scale search behaviour and spatial memory in honey bees (Apis mellifera L.).

    Science.gov (United States)

    Ushitani, Tomokazu; Perry, Clint J; Cheng, Ken; Barron, Andrew B

    2016-02-01

    Normally, worker honey bees (Apis mellifera) begin foraging when more than 2 weeks old as adults, but if individual bees or the colony is stressed, bees often begin foraging precociously. Here, we examined whether bees that accelerated their behavioural development to begin foraging precociously differed from normal-aged foragers in cognitive performance. We used a social manipulation to generate precocious foragers from small experimental colonies and tested their performance in a free-flight visual reversal learning task, and a test of spatial memory. To assess spatial memory, bees were trained to learn the location of a small sucrose feeder within an array of three landmarks. In tests, the feeder and one landmark were removed and the search behaviour of the bees was recorded. Performance of precocious and normal-aged foragers did not differ in a visual reversal learning task, but the two groups showed a clear difference in spatial memory. Flight behaviour suggested normal-aged foragers were better able to infer the position of the removed landmark and feeder relative to the remaining landmarks than precocious foragers. Previous studies have documented the cognitive decline of old foragers, but this is the first suggestion of a cognitive deficit in young foragers. These data imply that worker honey bees continue their cognitive development during the adult stage. These findings may also help to explain why precocious foragers perform quite poorly as foragers and have a higher than normal loss rate. © 2016. Published by The Company of Biologists Ltd.

  6. Testing of modern semiconductor memory structures

    NARCIS (Netherlands)

    Gaydadjiev, G.N.

    2007-01-01

    In this thesis, we study the problem of faults in modern semiconductor memory structures and their tests. According to the 2005 ITRS, the systems on chip (SoCs) are moving from logic and memory balanced chips to more memory dominated devices in order to cope with the increasing application

  7. [A new assessment for episodic memory. Episodic memory test and caregiver's episodic memory test].

    Science.gov (United States)

    Ojea Ortega, T; González Álvarez de Sotomayor, M M; Pérez González, O; Fernández Fernández, O

    2013-10-01

    The purpose of the episodic memory test and the caregiver's episodic memory test is to evaluate episodic memory according to its definition in a way that is feasible for families and achieves high degrees of sensitivity and specificity. We administered a test consisting of 10 questions about episodic events to 332 subjects, of whom 65 had Alzheimer's disease (AD), 115 had amnestic MCI (aMCI) and 152 showed no cognitive impairment according to Reisberg's global deterioration scale (GDS). We calculated the test's sensitivity and specificity to distinguish AD from episodic aMCI and from normal ageing. The area under the ROC curve for the diagnosis of aMCI was 0.94 and the best cut-off value was 20; for that value, sensitivity was 89% and specificity was 82%. For a diagnosis of AD, the area under the ROC curve was 0.99 and the best cut-off point was 17, with a sensitivity of 98% and a specificity of 91%. A subsequent study using similar methodology yielded similar results when the test was administered directly by the caregiver. The episodic memory test and the caregiver's episodic memory test are useful as brief screening tools for identifying patients with early-stage AD. It is suitable for use by primary care medical staff and in the home, since it can be administered by a caregiver. The test's limitations are that it must be administered by a reliable caregiver and the fact that it measures episodic memory only. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  8. Thermodynamic modelling of shape memory behaviour: some examples

    International Nuclear Information System (INIS)

    Stalmans, R.; Humbeeck, J. van; Delaey, L.

    1995-01-01

    This paper gives a general view of a recently developed thermodynamic model of the thermoelastic martensitic transformation. Unlike existing empirical, mathematical or thermodynamic models, this generalised thermodynamic model can be used to understand and describe quantitatively the overall thermomechanical behaviour of polycrystalline shape memory alloys. Important points of difference between this and previous thermodynamic models are that the contributions of the stored elastic energy and of the crystal defects are also included. In addition, the mathematical approach and the assumptions in this model are selected in such a way that the calculations yield close approximations of the real behaviour and that the final mathematical equations are relatively simple. Several illustrations indicate that this model, in contrast to other models, can be used to understand the shape memory behaviour of complex cases. As an example of quantitative calculations, it is shown that this modelling can be an effective tool in the ''design'' of multifunctional materials consisting of shape memory elements embedded in matrix materials. (orig.)

  9. Corrosion behaviour of Fe-Mn-Si based shape memory steels trained by cold rolling

    International Nuclear Information System (INIS)

    Soederberg, O.; Liu, X.W.; Ullakko, K.; Lindroos, V.K.

    1999-01-01

    Fe-Mn-Si based high nitrogen steels have been studied in recent years for potential industrial applications. These steels show good shape memory properties, high strength and excellent ductility. In the present study, the effects of training history on the corrosion properties of Fe-Mn-Si-Cr-Ni based high nitrogen steels were investigated. The corrosion behaviour of shape memory alloys was analyzed by implementing anodic polarisation measurements and immersion tests. The shape memory steels in annealed, deformed and recovered conditions were studied to examine the training effect on their corrosion behaviour. The features of the anodic polarisation curves indicated a general corrosion type of these steels. The experimental results showed that Cr and Mn had a marked influence on the corrosion behaviour of the steels, followed by Ni, N and V. It was also apparent that the deformation during the shape memory training by cold rolling decreased the corrosion stability, and the recovery heating reduced further their corrosion resistance. However, further studies are needed in order to better understand the corrosion behaviour of the investigated alloys. (orig.)

  10. Built-In Test Engine For Memory Test

    OpenAIRE

    McEvoy, Paul; Farrell, Ronan

    2004-01-01

    In this paper we will present an on-chip method for testing high performance memory devices, that occupies minimal area and retains full flexibility. This is achieved through microcode test instructions and the associated on-chip state machine. In addition, the proposed methodology will enable at-speed testing of memory devices. The relevancy of this work is placed in context with an introduction to memory testing and the techniques and algorithms generally used today.

  11. Recollection of episodic memory within the medial temporal lobe: behavioural dissociations from other types of memory.

    Science.gov (United States)

    Easton, Alexander; Eacott, Madeline J

    2010-12-31

    In recent years there has been significant debate about whether there is a single medial temporal lobe memory system or dissociable systems for episodic and other types of declarative memory. In addition there has been a similar debate over the dissociability of recollection and familiarity based processes in recognition memory. Here we present evidence from recent work using episodic memory tasks in animals that allows us to explore these issues in more depth. We review studies that demonstrate triple dissociations within the medial temporal lobe, with only the hippocampal system being necessary for episodic memory. Similarly we review behavioural evidence for a dissociation in a task of episodic memory in rats where animals with lesions of the fornix are only impaired at recollection of the episodic memory, not recognition within the same trial. This work, then, supports recent models of dissociable neural systems within the medial temporal lobe but also raises questions for future investigation about the interactions of these medial temporal lobe memory systems with other structures. Copyright © 2009 Elsevier B.V. All rights reserved.

  12. Testing Memories of Personally Experienced Events: The Testing Effect Seems Not to Persist in Autobiographical Memory

    Science.gov (United States)

    Emmerdinger, Kathrin J.; Kuhbandner, Christof

    2018-01-01

    Numerous studies have shown that retrieving contents from memory in a test improves long-term retention for those contents, even when compared to restudying (i.e., the “testing effect”). The beneficial effect of retrieval practice has been demonstrated for many different types of memory representations; however, one particularly important memory system has not been addressed in previous testing effect research: autobiographical memory. The aim of the present study was to examine the effect of retrieving memories for personally experienced events on long-term memory for those events. In an initial elicitation session, participants described memories for personally experienced events in response to a variety of cue words. In a retrieval practice/restudy session the following day, they repeatedly practiced retrieval for half of their memories by recalling and writing down the previously described events; the other half of memories was restudied by rereading and copying the event descriptions. Long-term retention of all previously collected memories was assessed at two different retention intervals (2 weeks and 13 weeks). In the retrieval practice session, a hypermnesic effect emerged, with memory performance increasing across the practice cycles. Long-term memory performance significantly dropped from the 2-weeks to the 13-weeks retention interval, but no significant difference in memory performance was observed between previously repeatedly retrieved and previously repeatedly restudied memories. Thus, in autobiographical memory, retrieval practice seems to be no more beneficial for long-term retention than repeated re-exposure. PMID:29881365

  13. Behavioural and neural evidence for the impact of fluency context on conscious memory.

    Science.gov (United States)

    Gomes, Carlos Alexandre; Mecklinger, Axel; Zimmer, Hubert

    2017-07-01

    It has been recently suggested that fluency may impact recognition memory performance when the fluency context varies from trial-to-trial. Surprisingly, such an effect has proved difficult to detect in the masked priming paradigm, one of the most popular means to increase fluency-based memory judgements. We conducted a functional magnetic resonance imaging (fMRI) experiment in which participants encoded words at study and, at test, performed a recognition memory task within a masked priming procedure. In order to optimise the chances of finding priming effects on recognition memory performance, we used low-frequency words, which have been shown to increase hits relative to false alarms and enhance masked priming effects. Fluency context was manipulated by either mixing primed and unprimed trials [Random context (RC) experiment] or blocking primed and unprimed trials [Blocked context (BC) experiment]. Behaviourally, priming affected high-confidence memory performance only in the RC experiment. This behavioural effect correlated positively with neural priming in several recognition memory regions. Moreover, we observed a functional coupling between the left middle temporal gyrus and the left parietal and posterior cingulate cortices that was greater for primed relative to unprimed words. In contrast, in the BC experiment, despite similar activity in recognition-memory-related regions, we did not find any significant correlations between neural and behavioural priming. Finally, we observed striking differences in the neural correlates of masked priming between the RC and BC experiments not only in location but also in direction of the neural response. Possible implications of these findings are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Non Volatile Flash Memory Radiation Tests

    Science.gov (United States)

    Irom, Farokh; Nguyen, Duc N.; Allen, Greg

    2012-01-01

    Commercial flash memory industry has experienced a fast growth in the recent years, because of their wide spread usage in cell phones, mp3 players and digital cameras. On the other hand, there has been increased interest in the use of high density commercial nonvolatile flash memories in space because of ever increasing data requirements and strict power requirements. Because of flash memories complex structure; they cannot be treated as just simple memories in regards to testing and analysis. It becomes quite challenging to determine how they will respond in radiation environments.

  15. Fracture behaviour of Cu-Al-Ni shape memory alloys obtained by powder metallurgy

    International Nuclear Information System (INIS)

    Rodriguez, P. P.; Perez-Saez, R. B.; Recarte, V.; San Juan, J.M.; Ruano, O. A.; No, M. L.

    2001-01-01

    Polycrystalline Cu-Al-Ni shape memory alloys have been scarcely employed for technological applications due to their high brittleness. The development of a new elaboration technique based on powder metallurgy has recently overcome this problem, through the improvement of the ductility of the produced alloys without affecting its shape memory properties. The fracture behaviour of an alloy obtained using the elaboration technique has been studied by means of Scanning Electron Microscopy and mechanical testing. The results show a ductile fracture with a maximum strain close to 13%, which is the best fracture behaviour obtained for Cu-Al-Ni polycrystals. The microstructure of such alloys ha been studied by means of Transmission Electron Microscopy, showing a poligonyzed structure in which martensite plated passing through the subboundaries easily. (Author) 19 refs

  16. Testing the Fracture Behaviour of Chocolate

    Science.gov (United States)

    Parsons, L. B.; Goodall, R.

    2011-01-01

    In teaching the materials science aspects of physics, mechanical behaviour is important due to its relevance to many practical applications. This article presents a method for experimentally examining the toughness of chocolate, including a design for a simple test rig, and a number of experiments that can be performed in the classroom. Typical…

  17. Influence of cilazapril on memory functions and sleep behaviour in comparison with metoprolol and placebo in healthy subjects.

    Science.gov (United States)

    Dietrich, B; Herrmann, W M

    1989-01-01

    1. In a controlled, randomized, double-blind study the influence of cilazapril and metoprolol on learning and memory functions and on sleep behaviour was investigated in healthy young volunteers under steady-state conditions. Twenty-three subjects were given either 2.5 mg cilazapril, 200 mg metoprolol, or placebo for 14 days in a latin square design separated by washout periods of 7 days. 2. To test memory functions different modalities--verbal, visual, numerical associative and two dimensional spatial memory were tested for recent anterograde recall, both short-term (less than 10 s) and middle-term (up to 15 min) were selected. The test had a content similar to that used in daily life situations. The sleep behaviour was tested both by objective (all night sleep EEG) and subjective measures. 3. Neither antihypertensive drug had an observable influence on memory performance at the dosages used under steady-state conditions. However, sleep was disturbed during metoprolol, while cilazapril could not be differentiated from placebo. The effects of metoprolol on sleep behaviour were observed in the objective and subjective measures. There was more frequent awakening during the night with the subjective complaint of difficulties in sleeping through. 4. From this study it is concluded that cilazapril has no major effect on memory functions and sleep behaviour. This is only true for the dosages given and under steady-state conditions.

  18. Test data generation for LRU cache-memory testing

    OpenAIRE

    Evgeni, Kornikhin

    2009-01-01

    System functional testing of microprocessors deals with many assembly programs of given behavior. The paper proposes new constraint-based algorithm of initial cache-memory contents generation for given behavior of assembly program (with cache misses and hits). Although algorithm works for any types of cache-memory, the paper describes algorithm in detail for basis types of cache-memory only: fully associative cache and direct mapped cache.

  19. Test-Retest Reliability of Computerized, Everyday Memory Measures and Traditional Memory Tests.

    Science.gov (United States)

    Youngjohn, James R.; And Others

    Test-retest reliabilities and practice effect magnitudes were considered for nine computer-simulated tasks of everyday cognition and five traditional neuropsychological tests. The nine simulated everyday memory tests were from the Memory Assessment Clinic battery as follows: (1) simple reaction time while driving; (2) divided attention (driving…

  20. Strategic value-directed learning and memory in Alzheimer's disease and behavioural-variant frontotemporal dementia.

    Science.gov (United States)

    Wong, Stephanie; Irish, Muireann; Savage, Greg; Hodges, John R; Piguet, Olivier; Hornberger, Michael

    2018-02-12

    In healthy adults, the ability to prioritize learning of highly valued information is supported by executive functions and enhances subsequent memory retrieval for this information. In Alzheimer's disease (AD) and behavioural-variant frontotemporal dementia (bvFTD), marked deficits are evident in learning and memory, presenting in the context of executive dysfunction. It is unclear whether these patients show a typical memory bias for higher valued stimuli. We administered a value-directed word-list learning task to AD (n = 10) and bvFTD (n = 21) patients and age-matched healthy controls (n = 22). Each word was assigned a low, medium or high point value, and participants were instructed to maximize the number of points earned across three learning trials. Participants' memory for the words was assessed on a delayed recall trial, followed by a recognition test for the words and corresponding point values. Relative to controls, both patient groups showed poorer overall learning, delayed recall and recognition. Despite these impairments, patients with AD preferentially recalled high-value words on learning trials and showed significant value-directed enhancement of recognition memory for the words and points. Conversely, bvFTD patients did not prioritize recall of high-value words during learning trials, and this reduced selectivity was related to inhibitory dysfunction. Nonetheless, bvFTD patients showed value-directed enhancement of recognition memory for the point values, suggesting a mismatch between memory of high-value information and the ability to apply this in a motivationally salient context. Our findings demonstrate that value-directed enhancement of memory may persist to some degree in patients with dementia, despite pronounced deficits in learning and memory. © 2018 The British Psychological Society.

  1. Modeling the behaviour of shape memory materials under large deformations

    Science.gov (United States)

    Rogovoy, A. A.; Stolbova, O. S.

    2017-06-01

    In this study, the models describing the behavior of shape memory alloys, ferromagnetic materials and polymers have been constructed, using a formalized approach to develop the constitutive equations for complex media under large deformations. The kinematic and constitutive equations, satisfying the principles of thermodynamics and objectivity, have been derived. The application of the Galerkin procedure to the systems of equations of solid mechanics allowed us to obtain the Lagrange variational equation and variational formulation of the magnetostatics problems. These relations have been tested in the context of the problems of finite deformation in shape memory alloys and ferromagnetic materials during forward and reverse martensitic transformations and in shape memory polymers during forward and reverse relaxation transitions from a highly elastic to a glassy state.

  2. The Unintentional Memory Load in Tests for Young Children.

    Science.gov (United States)

    Jones, Margaret Hubbard

    The validity of certain standardized tests may be affected by the short-term memory load therein and its relation to a child's short-term memory capacity. Factors of testing which increase a test's memory load and consequently interfere with comprehension are discussed. It is hypothesized that a test which strains the short-term memory capacity of…

  3. Can Testing Immunize Memories against Interference?

    Science.gov (United States)

    Potts, Rosalind; Shanks, David R.

    2012-01-01

    Testing typically enhances subsequent recall of tested material. In contrast, it has been proposed that consolidated memories can be destabilized when reactivated and then need to be reconsolidated in order to persist. Learning new material immediately after reactivation may disrupt reconsolidation. We investigated whether the well-known benefits…

  4. Test Expectancy and Memory for Important Information

    Science.gov (United States)

    Middlebrooks, Catherine D.; Murayama, Kou; Castel, Alan D.

    2017-01-01

    Prior research suggests that learners study and remember information differently depending upon the type of test they expect to later receive. The current experiments investigate how testing expectations impact the study of and memory for valuable information. Participants studied lists of words ranging in value from 1 to 10 points with the goal…

  5. Hysteresis behaviour of thermoelastic alloys: some shape memory alloys models

    International Nuclear Information System (INIS)

    Lexcellent, C.; Torra, V.; Raniecki, B.

    1993-01-01

    The hysteretic behaviour of shape memory alloys (SMA) needs a more and more thin analysis because of its importance for technological applications. The comparison between different approaches allows to explicite the specifity of every model (macroscopic approach, micro-macro level, local description, phenomenological approach) and their points of convergence. On one hand, a thermodynamic treatment with a free energy expression as a mixing rule of each phase (parent or austenite phase and martensite) by adding a coupling term: the configurational energy, allowes modelling of material hysteresis loops. On the other hand, a phenomenological treatment based on a local investigation of two single crystals with a visualisation of microscopic parameters allows to perceive the phase transition mechanisms (nucleation, growth). All the obtained results show the importance of entropy production (or of the definition of the configurational energy term) for the correct description of hysteresis loops (subloops or external). (orig.)

  6. Working Memory and Behavioural Problems in Relation to Malay Writing of Primary School Children

    Science.gov (United States)

    Ling, Teo-Sieak; Jiar, Yeo-Kee

    2017-01-01

    Deficit in working memory is common among young children across multiple abilities. Teachers have pointed to poor memory as one contributing factor to inattentiveness and short attention spans as well as some behavioural problems among students. This study aimed to explore the relationship among working memory, externalizing and internalizing…

  7. Test and Behaviour Driven Development with Python

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    Experience has taught us that bugs are impossible to avoid when programming. Specially on continuous delivery processes where there are new versions that refactor or incorporate new modules to the project. Although, there are different tools which help us to ensure code quality by enabling developers to catch bugs while still in the development stage. In this talk, I will talk about Test-driven development(TDD) and Behaviour-Driven development (BDD) methodologies focused on web development. Also, I will present an overview of unit testing tools as Selenium or Behave, which help us to produce working software, with fewer bugs, quickly and consistently.

  8. Assessment of Behavioural Markers of Autonoetic Consciousness during Episodic Autobiographical Memory Retrieval: A Preliminary Analysis

    Directory of Open Access Journals (Sweden)

    M. Irish

    2008-01-01

    Full Text Available There is ongoing theoretical debate regarding episodic memory and how it can be accurately measured, in particular if the focus should be content-based recall of episodic details or something more experiential involving the subjective capacity to mentally travel back in time and “re-live” aspects of the original event. The autonoetic subscale of the Episodic Autobiographical Memory Interview (EAMI is presented here as a new test instrument that attempts to redress theoretical and methodological shortcomings in autobiographical memory assessment. The EAMI merges a phenomenological detail-based approach with an assessment of autonoetic consciousness, departing considerably from traditional Remember/Know paradigms used within this field. We present findings from an initial pilot study investigating the potential markers of autonoetic consciousness that may accompany episodic retrieval. Key behavioural indices of autonoetic consciousness, notably those of viewer perspective, visual imagery, and emotional re-experiencing, emerged as being inextricably bound with the level of phenomenological detail recalled and the overall re-living judgment. The autonoetic subscale of the EAMI permits conceptually refined assessment of episodic personal memories and the accompanying subjective experience of mental re-living, characteristic of episodic memory.

  9. Modification of Fear Memory by Pharmacological and Behavioural Interventions during Reconsolidation.

    Science.gov (United States)

    Thome, Janine; Koppe, Georgia; Hauschild, Sophie; Liebke, Lisa; Schmahl, Christian; Lis, Stefanie; Bohus, Martin

    2016-01-01

    Dysfunctional fear responses play a central role in many mental disorders. New insights in learning and memory suggest that pharmacological and behavioural interventions during the reconsolidation of reactivated fear memories may increase the efficacy of therapeutic interventions. It has been proposed that interventions applied during reconsolidation may modify the original fear memory, and thus prevent the spontaneous recovery and reinstatement of the fear response. We investigated whether pharmacological (propranolol) and behavioural (reappraisal, multisensory stimulation) interventions reduce fear memory, and prevent reinstatement of fear in comparison to a placebo control group. Eighty healthy female subjects underwent a differential fear conditioning procedure with three stimuli (CS). Two of these (CS+) were paired with an electric shock on day 1. On day 2, 20 subjects were pseudo-randomly assigned to either the propranolol or placebo condition, or underwent one of the two behavioural interventions after one of the two CS+ was reactivated. On day 3, all subjects underwent an extinction phase, followed by a reinstatement test. Dependent variables were US expectancy ratings, fear-potentiated startle, and skin conductance response. Differential fear responses to the reactivated and non-reactivated CS+ were observed only in the propranolol condition. Here, the non-reactivated CS+ evoked stronger fear-potentiated startle-responses compared to the placebo group. None of the interventions prevented the return of the extinguished fear response after re-exposure to the unconditioned stimulus. Our data are in line with an increasing body of research stating that the occurrence of reconsolidation may be constrained by boundary conditions such as subtle differences in experimental manipulations and instructions. In conclusion, our findings do not support a beneficial effect in using reconsolidation processes to enhance effects of psychotherapeutic interventions. This

  10. Modification of Fear Memory by Pharmacological and Behavioural Interventions during Reconsolidation

    Science.gov (United States)

    Thome, Janine; Koppe, Georgia; Hauschild, Sophie; Liebke, Lisa; Schmahl, Christian; Lis, Stefanie; Bohus, Martin

    2016-01-01

    Background Dysfunctional fear responses play a central role in many mental disorders. New insights in learning and memory suggest that pharmacological and behavioural interventions during the reconsolidation of reactivated fear memories may increase the efficacy of therapeutic interventions. It has been proposed that interventions applied during reconsolidation may modify the original fear memory, and thus prevent the spontaneous recovery and reinstatement of the fear response. Methods We investigated whether pharmacological (propranolol) and behavioural (reappraisal, multisensory stimulation) interventions reduce fear memory, and prevent reinstatement of fear in comparison to a placebo control group. Eighty healthy female subjects underwent a differential fear conditioning procedure with three stimuli (CS). Two of these (CS+) were paired with an electric shock on day 1. On day 2, 20 subjects were pseudo-randomly assigned to either the propranolol or placebo condition, or underwent one of the two behavioural interventions after one of the two CS+ was reactivated. On day 3, all subjects underwent an extinction phase, followed by a reinstatement test. Dependent variables were US expectancy ratings, fear-potentiated startle, and skin conductance response. Results Differential fear responses to the reactivated and non-reactivated CS+ were observed only in the propranolol condition. Here, the non-reactivated CS+ evoked stronger fear-potentiated startle-responses compared to the placebo group. None of the interventions prevented the return of the extinguished fear response after re-exposure to the unconditioned stimulus. Conclusions Our data are in line with an increasing body of research stating that the occurrence of reconsolidation may be constrained by boundary conditions such as subtle differences in experimental manipulations and instructions. In conclusion, our findings do not support a beneficial effect in using reconsolidation processes to enhance effects of

  11. On the power of autobiographical memories: from threat and challenge appraisals to actual behaviour.

    Science.gov (United States)

    Selimbegović, Leila; Régner, Isabelle; Huguet, Pascal; Chatard, Armand

    2016-11-01

    Autobiographical memories are a major feature of mental life in humans. However, research on the influence of autobiographical recall on actual behaviour is scarce. We predicted and found that general memories of failure and specific memories of success resulted in worse performance than general memories of success and specific memories of failure. This performance pattern was mediated by task appraisal, suggesting that autobiographical memories (of failure and success) impact performance by shaping the perception of the upcoming task. Combined with the fact that these effects occurred even when the content of autobiographical memories was unrelated to the upcoming task, the present research represents an important step forward in understanding how autobiographical recall influences actual behaviour.

  12. Working memory load affects repetitive behaviour but not cognitive flexibility in adolescent autism spectrum disorder.

    Science.gov (United States)

    Wolff, Nicole; Chmielewski, Witold X; Beste, Christian; Roessner, Veit

    2017-03-16

    Autism spectrum disorder (ASD) is associated with repetitive and stereotyped behaviour, suggesting that cognitive flexibility may be deficient in ASD. A central, yet not examined aspect to understand possible deficits in flexible behaviour in ASD relates (i) to the role of working memory and (ii) to neurophysiological mechanisms underlying behavioural modulations. We analysed behavioural and neurophysiological (EEG) correlates of cognitive flexibility using a task-switching paradigm with and without working memory load in adolescents with ASD and typically developing controls (TD). Adolescents with ASD versus TD show similar performance in task switching with no memory load, indicating that 'pure' cognitive flexibility is not in deficit in adolescent ASD. However performance during task repetition decreases with increasing memory load. Neurophysiological data reflect the pattern of behavioural effects, showing modulations in P2 and P3 event-related potentials. Working memory demands affect repetitive behaviour while processes of cognitive flexibility are unaffected. Effects emerge due to deficits in preparatory attentional processes and deficits in task rule activation, organisation and implementation of task sets when repetitive behaviour is concerned. It may be speculated that the habitual response mode in ASD (i.e. repetitive behaviour) is particularly vulnerable to additional demands on executive control processes.

  13. Influence of chewing behaviour on memory and spatial learning in albino BALB/c mice.

    Science.gov (United States)

    Aguirre Siancas, E E

    2017-05-01

    Since the relationship between chewing and cognitive functions has not been fully elucidated, this study aimed to determine the impact of chewing behaviour on spatial learning and memory in albino male BALB/c mice. Twenty mice aged 8 weeks were divided into 2 equal groups. The regular chewing group was fed with uncrushed grains (the same diet given to all 20 mice since they were weaned) and the limited chewing group was fed with crushed grains. At 16 weeks of age, the mice were evaluated over 5 days, including a 4-day acquisition phase prior to a probe test of spatial learning and memory in the Morris water maze on the fifth day. A comparison of the regular chewing group and the limited chewing group found no significant differences in either the acquisition phase or the probe test. However, there were significant differences in the acquisition phase for just the regular chewing group when comparing results from the first day to those from the other 3 days. The results suggest that regular chewing affects spatial learning and memory since mice in the regular chewing group decreased their times to find the hidden platform during the acquisition phase. Copyright © 2015 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Examining the Link between Working Memory Behaviour and Academic Attainment in Children with ADHD

    Science.gov (United States)

    Alloway, Tracy Packiam; Gathercole, Susan E.; Elliott, Julian

    2010-01-01

    Aim: The aim of the present study was to investigate whether behaviours typical of working memory problems are associated with poor academic attainment in those with attention-deficit-hyperactivity disorder (ADHD), as well as a non-clinical group identified on the basis of working memory difficulties. Method: Children clinically diagnosed with…

  15. [Psychometric validation of the telephone memory test].

    Science.gov (United States)

    Ortiz, T; Fernández, A; Martínez-Castillo, E; Maestú, F; Martínez-Arias, R; López-Ibor, J J

    1999-01-01

    Several pathologies (i.e. Alzheimer's disease) that courses with memory alterations, appears in a context of impaired cognitive status and mobility. In recent years, several investigations were carried out in order to design short batteries that detect those subjects under risk of dementia. Some of this batteries were also design to be administrated over the telephone, trying to overcome the accessibility limitations of this patients. In this paper we present a battery (called Autotest de Memoria) essentially composed by episodic and semantic memory tests, administered both over the telephone and face to face. This battery was employed in the cognitive assessment of healthy controls and subjects diagnosed as probable Alzheimer's disease patients. Results show the capability of this battery in order to discriminate patients and healthy controls, a great sensibility and specificity, and a nearly absolute parallelism of telephone and face to face administrations. These data led us to claim the usefulness and practicality of our so called Memoria>.

  16. Visual short-term memory deficits in REM sleep behaviour disorder mirror those in Parkinson's disease.

    Science.gov (United States)

    Rolinski, Michal; Zokaei, Nahid; Baig, Fahd; Giehl, Kathrin; Quinnell, Timothy; Zaiwalla, Zenobia; Mackay, Clare E; Husain, Masud; Hu, Michele T M

    2016-01-01

    Individuals with REM sleep behaviour disorder are at significantly higher risk of developing Parkinson's disease. Here we examined visual short-term memory deficits--long associated with Parkinson's disease--in patients with REM sleep behaviour disorder without Parkinson's disease using a novel task that measures recall precision. Visual short-term memory for sequentially presented coloured bars of different orientation was assessed in 21 patients with polysomnography-proven idiopathic REM sleep behaviour disorder, 26 cases with early Parkinson's disease and 26 healthy controls. Three tasks using the same stimuli controlled for attentional filtering ability, sensorimotor and temporal decay factors. Both patients with REM sleep behaviour disorder and Parkinson's disease demonstrated a deficit in visual short-term memory, with recall precision significantly worse than in healthy controls with no deficit observed in any of the control tasks. Importantly, the pattern of memory deficit in both patient groups was specifically explained by an increase in random responses. These results demonstrate that it is possible to detect the signature of memory impairment associated with Parkinson's disease in individuals with REM sleep behaviour disorder, a condition associated with a high risk of developing Parkinson's disease. The pattern of visual short-term memory deficit potentially provides a cognitive marker of 'prodromal' Parkinson's disease that might be useful in tracking disease progression and for disease-modifying intervention trials. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain.

  17. Olfactory memory established during trophallaxis affects food search behaviour in ants.

    Science.gov (United States)

    Provecho, Yael; Josens, Roxana

    2009-10-01

    Camponotus mus ants can associate sucrose and odour at the source during successive foraging cycles and use this memory to locate the nectar in the absence of other cues. These ants perform conspicuous trophallactic behaviour during recruitment while foraging for nectar. In this work, we studied whether Camponotus mus ants are able to establish this odour-sucrose association in the social context of trophallaxis and we evaluated this memory in another context previously experienced by the ant, as a nectar source. After a single trophallaxis of a scented solution, the receiver ant was tested in a Y-maze without any reward, where two scents were presented: in one arm, the solution scent and in the other, a new scent. Ants consistently chose the arm with the solution scent and stayed longer therein. Trophallaxis duration had no effect on the arm choice or with the time spent in each arm. Workers are able to associate an odour (conditioned stimulus) with the sucrose (unconditioned stimulus) they receive through a social interaction and use this memory as choice criteria during food searching.

  18. The effects of free recall testing on subsequent source memory.

    Science.gov (United States)

    Brewer, Gene A; Marsh, Richard L; Meeks, Joseph T; Clark-Foos, Arlo; Hicks, Jason L

    2010-05-01

    The testing effect is the finding that prior retrieval of information from memory will result in better subsequent memory for that material. One explanation for these effects is that initial free recall testing increases the recollective details for tested information, which then becomes more available during a subsequent test phase. In three experiments we explored this hypothesis using a source-monitoring test phase after the initial free recall tests. We discovered that memory is differentially enhanced for certain recollective details depending on the nature of the free recall task. Thus further research needs to be conducted to specify how different kinds of memorial details are enhanced by free recall testing.

  19. Self-Testing Static Random-Access Memory

    Science.gov (United States)

    Chau, Savio; Rennels, David

    1991-01-01

    Proposed static random-access memory for computer features improved error-detecting and -correcting capabilities. New self-testing scheme provides for detection and correction of errors at any time during normal operation - even while data being written into memory. Faults in equipment causing errors in output data detected by repeatedly testing every memory cell to determine whether it can still store both "one" and "zero", without destroying data stored in memory.

  20. Testing for structural change in the presence of long memory

    OpenAIRE

    Krämer, Walter; Sibbertsen, Philipp

    2000-01-01

    We derive the limiting null distributions of the standard and OLS-based CUSUM-tests for structural change of the coefficients of a linear regression model in the context of long memory disturbances. We show that both tests behave fundamentally different in a long memory environment, as compared to short memory, and that long memory is easily mistaken for structural change when standard critical values are employed.

  1. Evaluation of behaviour testing for human directed aggression in dogs

    NARCIS (Netherlands)

    Borg, van der J.A.M.; Beerda, B.; Ooms, M.; Silveira de Souza, A.; Hagen, M.; Kemp, B.

    2010-01-01

    Behaviour test batteries are used to identify aggressive dogs. The Dutch Socially Acceptable Behaviour (SAB)-test has been used since 2001 to select against unwanted aggression and fear in specific dog breeds, though much is unknown yet regarding its reliability, validity and feasibility. In this

  2. Computational modelling of memory retention from synapse to behaviour

    Science.gov (United States)

    van Rossum, Mark C. W.; Shippi, Maria

    2013-03-01

    One of our most intriguing mental abilities is the capacity to store information and recall it from memory. Computational neuroscience has been influential in developing models and concepts of learning and memory. In this tutorial review we focus on the interplay between learning and forgetting. We discuss recent advances in the computational description of the learning and forgetting processes on synaptic, neuronal, and systems levels, as well as recent data that open up new challenges for statistical physicists.

  3. Computational modelling of memory retention from synapse to behaviour

    International Nuclear Information System (INIS)

    Van Rossum, Mark C W; Shippi, Maria

    2013-01-01

    One of our most intriguing mental abilities is the capacity to store information and recall it from memory. Computational neuroscience has been influential in developing models and concepts of learning and memory. In this tutorial review we focus on the interplay between learning and forgetting. We discuss recent advances in the computational description of the learning and forgetting processes on synaptic, neuronal, and systems levels, as well as recent data that open up new challenges for statistical physicists. (paper)

  4. Mangifera indica extract (Vimang) impairs aversive memory without affecting open field behaviour or habituation in rats.

    Science.gov (United States)

    Preissler, Thales; Martins, Márcio Rodrigo; Pardo-Andreu, Gilberto L; Henriques, João Antônio Pêgas; Quevedo, João; Delgado, Rene; Roesler, Rafael

    2009-06-01

    Vimang is an aqueous extract of Mangifera indica L, used in Cuba for the treatment of immunopathological disorders. Increasing evidence from preclinical studies indicates that Vimang displays antioxidant, antiallergic, analgesic and antiinflammatory actions. The present study investigated the effects of systemic administration of Vimang on behavioural outcomes of neurological function in rats. A single oral administration of Vimang produced an impairment of short- and long-term retention of memory for aversive training when given either 1 h pretraining or immediately posttraining, but not 8 h posttraining. Vimang did not affect open field behaviour or habituation. The results indicate that Vimang might induce deficits of emotionally motivated memory without affecting nonassociative memory, locomotion, exploratory behaviour or anxiety. (c) 2008 John Wiley & Sons, Ltd.

  5. Olfactory memory established during trophallaxis affects food search behaviour in ants

    OpenAIRE

    Provecho, Y.; Josens, R.

    2009-01-01

    Camponotus mus ants can associate sucrose and odour at the source during successive foraging cycles and use this memory to locate the nectar in the absence of other cues. These ants perform conspicuous trophallactic behaviour during recruitment while foraging for nectar. In this work, we studied whether Camponotus mus ants are able to establish this odour-sucrose association in the social context of trophallaxis and we evaluated this memory in another context previously experienced by the ant...

  6. Executive Functions and Working Memory Behaviours in Children with a Poor Working Memory

    Science.gov (United States)

    St. Clair-Thompson, Helen L.

    2011-01-01

    Previous research has suggested that working memory difficulties play an integral role in children's underachievement at school. However, working memory is just one of several executive functions. The extent to which problems in working memory extend to other executive functions is not well understood. In the current study 38 children with a poor…

  7. Factors influencing shape memory effect and phase transformation behaviour of Fe-Mn-Si based shape memory alloys

    International Nuclear Information System (INIS)

    Li, H.; Dunne, D.; Kennon, N.

    1999-01-01

    The objective of this research work was to investigate the factors influencing the shape memory effect and phase transformation behaviour of three Fe-Mn-Si based shape memory alloys: Fe-28Mn-6Si, Fe-13Mn-5Si-10Cr-6Ni and Fe-20Mn-6Si-7Cr-1Cu. The research results show that the shape memory capacity of Fe-Mn-Si based shape memory alloys varies with annealing temperature, and this effect can be explained in terms of the effect of annealing on γ ε transformation. The nature and concentration of defects in austenite are strongly affected by annealing conditions. A high annealing temperature results in a low density of stacking faults, leading to a low nucleation rate during stress induced γ→ε transformation. The growth of ε martensite plates is favoured rather than the formation of new ε martensite plates. Coarse martensite plates produce high local transformation strains which can be accommodated by local slip deformation, leading to a reduction in the reversibility of the martensitic transformation and to a degradation of the shape memory effect. Annealing at low temperatures (≤673 K) for reasonable times does not eliminate complex defects (dislocation jogs, kinks and vacancy clusters) created by hot and cold working strains. These defects can retard the movement and rearrangement of Shockley partial dislocations, i.e. suppress γ→ε transformation, also leading to a degradation of shape memory effect. Annealing at about 873 K was found to be optimal to form the dislocation structures which are favourable for stress induced martensitic transformation, thus resulting in the best shape memory behaviour. (orig.)

  8. The influence of lotteries on employees' workplace HIV testing behaviour.

    Science.gov (United States)

    Weihs, Martin; Meyer-Weitz, Anna; Baasner-Weihs, Friederike

    2018-03-01

    The aim of the study was to understand how lottery incentives influenced the HIV counselling and testing (HCT) behaviour and behaviour intention of shop-floor workers who participated in a workplace HCT campaign initiative in two companies in the Nelson Mandela Bay municipality, South Africa. A post-test only quasi-experimental approach was used. The data were first collected, using a self-administered cross-sectional survey instrument, among the control group (n = 88) followed by the experimental group (n = 110) after the advent of HIV testing and lotteries was announced. HIV testing behaviour data were collected on the days of the HIV testing events. The theory of planned behaviour (TPB) was used as guiding theory. Principal component analysis (PCA), t- and chi-square tests, and logistic regression were conducted to analyse the data. A significant increase in the mean scores of the experimental as compared to the control condition for the subjective norm's construct (t = -3.55, p < 0.001) and HIV testing behaviour intention (χ 2 = 12.35, p < 0.001) was measured following the announcement of lottery incentives. The constructs of TPB explained 40% of the variance in HCT behaviour intention (R 2 = 0.40). The strongest predictor of behaviour intention was the subjective norm (B = 0.435 and p < 0.001), followed by the attitudinal component (B = 0.323 and p = 0.040). The announcement of lotteries made shop-floor workers develop a stronger intention to participate in workplace HIV testing through anticipation of stronger social support and encouragement. It was not possible to link behaviour intention to behaviour due to missing data. The findings point to the importance of providing workers with an opportunity to openly discuss HIV testing thus allowing mitigation of HIV stigma and discrimination and permitting HIV testing to become socially sanctioned and seen as part of a collective effort.

  9. Prioritizing Test Cases for Memory Leaks in Android Applications

    Institute of Scientific and Technical Information of China (English)

    Ju Qian; Di Zhou

    2016-01-01

    Mobile applications usually can only access limited amount of memory. Improper use of the memory can cause memory leaks, which may lead to performance slowdowns or even cause applications to be unexpectedly killed. Although a large body of research has been devoted into the memory leak diagnosing techniques after leaks have been discovered, it is still challenging to find out the memory leak phenomena at first. Testing is the most widely used technique for failure discovery. However, traditional testing techniques are not directed for the discovery of memory leaks. They may spend lots of time on testing unlikely leaking executions and therefore can be inefficient. To address the problem, we propose a novel approach to prioritize test cases according to their likelihood to cause memory leaks in a given test suite. It firstly builds a prediction model to determine whether each test can potentially lead to memory leaks based on machine learning on selected code features. Then, for each input test case, we partly run it to get its code features and predict its likelihood to cause leaks. The most suspicious test cases will be suggested to run at first in order to reveal memory leak faults as soon as possible. Experimental evaluation on several Android applications shows that our approach is effective.

  10. Behavioural testing based breeding policy reduces the prevalence of fear and aggression related behaviour in Rottweilers

    NARCIS (Netherlands)

    Borg, van der Joanne A.M.; Graat, Lisette; Beerda, Bonne

    2017-01-01

    Behavioural testing allows to exclude dogs that are fearful and aggressive from the breeding population, but relatively little is known about the effectiveness of such strategies in practice. From 2001 till 2009 parent purebred Dutch Rottweilers had to pass the Socially Acceptable Behaviour

  11. Relationships between the National Adult Reading Test and memory.

    Science.gov (United States)

    Frick, Andreas; Wahlin, Tarja-Brita Robins; Pachana, Nancy A; Byrne, Gerard J

    2011-05-01

    The aims of this study were to investigate the relationships between performance on the National Adult Reading Test (NART) and retrospective, concurrent, and prospective memory functioning, as well as between the NART and change in memory functioning over time. NART administered in 2005 was used as a predictor for memory functioning in 2001, 2005, and 2008, and change in memory functioning from 2001 to 2008. Outcome measures were Logical Memory II, Letter-Number Sequencing, and Spatial Span from the Wechsler Memory Scale. Participants were 319 healthy women aged 40-79 years at baseline (2001). Significant correlations were found between the number of errors on the NART and memory measures in 2001, 2005, and 2008; Logical Memory II (r = -.41, -.38, -.39, respectively), Letter-Number Sequencing (r = -.38, -.35, -.36, respectively) and Spatial Span (r = -.23, -.22, -.19, respectively; all p values memory, after controlling for age, level of education and socioeconomic status. NART also significantly added to predictions of change in Logical Memory II and Letter-Number Sequencing over a 7-year period. The results indicate that the NART is correlated with episodic and working memory, and that the NART added to predictions of change in verbal episodic and working memory. Although the relationships are only moderate at best, the NART may be used in conjunction with demographic information and clinical reasoning to estimate premorbid memory functioning.

  12. Deployable auxetic shape memory alloy cellular antenna demonstrator: design, manufacturing and modal testing

    International Nuclear Information System (INIS)

    Jacobs, S; Coconnier, C; DiMaio, D; Scarpa, F; Martinez, J; Toso, M

    2012-01-01

    This work describes the design, manufacturing and testing of a deployable antenna for deep-space missions based on a hybrid honeycomb truss made of shape memory alloy (SMA). The deployable characteristics are enhanced by the equivalent auxetic (negative Poisson’s ratio) behaviour of the cellular configuration. Specific emphasis is placed on the modal analysis techniques used to test the lightweight SMA structure. (paper)

  13. Heterogeneous Agent Model with Memory and Asset Price Behaviour

    Czech Academy of Sciences Publication Activity Database

    Vošvrda, Miloslav; Vácha, Lukáš

    2003-01-01

    Roč. 12, č. 2 (2003), s. 155-168 ISSN 1210-0455 R&D Projects: GA ČR GA402/00/0439; GA ČR GA402/01/0034 Institutional research plan: CEZ:AV0Z1075907 Keywords : efficient markets hypothesis * technical trading rules * heterogeneous agent model with memory and learning Subject RIV: AH - Economics

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

    Science.gov (United States)

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

    2017-08-01

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

  15. Towards improved behavioural testing in aquatic toxicology: Acclimation and observation times are important factors when designing behavioural tests with fish.

    Science.gov (United States)

    Melvin, Steven D; Petit, Marie A; Duvignacq, Marion C; Sumpter, John P

    2017-08-01

    The quality and reproducibility of science has recently come under scrutiny, with criticisms spanning disciplines. In aquatic toxicology, behavioural tests are currently an area of controversy since inconsistent findings have been highlighted and attributed to poor quality science. The problem likely relates to limitations to our understanding of basic behavioural patterns, which can influence our ability to design statistically robust experiments yielding ecologically relevant data. The present study takes a first step towards understanding baseline behaviours in fish, including how basic choices in experimental design might influence behavioural outcomes and interpretations in aquatic toxicology. Specifically, we explored how fish acclimate to behavioural arenas and how different lengths of observation time impact estimates of basic swimming parameters (i.e., average, maximum and angular velocity). We performed a semi-quantitative literature review to place our findings in the context of the published literature describing behavioural tests with fish. Our results demonstrate that fish fundamentally change their swimming behaviour over time, and that acclimation and observational timeframes may therefore have implications for influencing both the ecological relevance and statistical robustness of behavioural toxicity tests. Our review identified 165 studies describing behavioural responses in fish exposed to various stressors, and revealed that the majority of publications documenting fish behavioural responses report extremely brief acclimation times and observational durations, which helps explain inconsistencies identified across studies. We recommend that researchers applying behavioural tests with fish, and other species, apply a similar framework to better understand baseline behaviours and the implications of design choices for influencing study outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Natural variation in memory formation among Nasonia parasitic wasps : from genes to behaviour

    NARCIS (Netherlands)

    Hoedjes, K.M.

    2014-01-01

    The ability to learn and form memory has been demonstrated in various animal species, ranging from relatively simple invertebrates, such as snails and insects, to more complex vertebrate species, including birds and mammals. The opportunity to acquire new skills or to adapt behaviour

  17. Guppies Show Behavioural but Not Cognitive Sex Differences in a Novel Object Recognition Test.

    Directory of Open Access Journals (Sweden)

    Tyrone Lucon-Xiccato

    Full Text Available The novel object recognition (NOR test is a widely-used paradigm to study learning and memory in rodents. NOR performance is typically measured as the preference to interact with a novel object over a familiar object based on spontaneous exploratory behaviour. In rats and mice, females usually have greater NOR ability than males. The NOR test is now available for a large number of species, including fish, but sex differences have not been properly tested outside of rodents. We compared male and female guppies (Poecilia reticulata in a NOR test to study whether sex differences exist also for fish. We focused on sex differences in both performance and behaviour of guppies during the test. In our experiment, adult guppies expressed a preference for the novel object as most rodents and other species do. When we looked at sex differences, we found the two sexes showed a similar preference for the novel object over the familiar object, suggesting that male and female guppies have similar NOR performances. Analysis of behaviour revealed that males were more inclined to swim in the proximity of the two objects than females. Further, males explored the novel object at the beginning of the experiment while females did so afterwards. These two behavioural differences are possibly due to sex differences in exploration. Even though NOR performance is not different between male and female guppies, the behavioural sex differences we found could affect the results of the experiments and should be carefully considered when assessing fish memory with the NOR test.

  18. Stress recovery behaviour of an Fe–Mn–Si–Cr–Ni–VC shape memory alloy used for prestressing

    International Nuclear Information System (INIS)

    Lee, W J; Weber, B; Feltrin, G; Czaderski, C; Motavalli, M; Leinenbach, C

    2013-01-01

    This paper describes the stress recovery behaviour of an Fe–17Mn–5Si–10Cr–4Ni–1(V, C) (mass%) shape memory alloy used for prestressing of civil structures. The prestressing due to the shape memory effect was simulated by a series of tests with pre-straining of the material followed by heating and cooling back at constant strain. Different pre-strain and heating conditions were examined. Moreover, the response due to additional mechanical and thermal cyclic loading has been investigated. These results were used to predict the partial prestress loss in a structure due to variable loading during operation. Finally, a heating test at constant strain was performed after the cyclic loading to check the possibility of reactivating the prestress lost during an exceptionally high load. (paper)

  19. Generalization of the memory integer model for the analysis of the quasi-static behaviour of polyurethane foams

    International Nuclear Information System (INIS)

    Jmal, Hamdi; Ju, Ming Lei; Dupuis, Raphael; Aubry, Evelyne

    2014-01-01

    Polyurethane foam is a cellular material characterized by an interesting mechanical spectrum of properties: low density, capacity to absorb the deformation energy and low stiffness. This spectrum of properties makes polyurethane foam commonly used in many thermal, acoustic and comfort applications. Several models, such as memory, hyper-elastic and pseudo-elastic models have been developed in the literature to describe the mechanical response of polyurethane foam under quasi-static and dynamic test conditions. The main disadvantage of these models is the dependence of their parameters against the test conditions (strain rate, maximum compression level, etc). This affects the general character of their representativeness to the quasi-static and dynamic behaviours of polyurethane foam. The main goal of this article is to implement reliable mechanical model which is able to provide the quasi-static response of the polyurethane foam under different strain rates and large compressive deformation. The dimensional parameters of our model can be expressed by the product of two independent parts; the first contain only the test conditions and the second define the dimensionless and invariant parameters that characterize the foam material. The developed model has been proposed after several experimental studies allowing the apprehension of the quasi-static behaviour (through unidirectional compression tests). The polyurethane foam, under large deformations, exhibits a nonlinear elastic behaviour and viscoelastic behaviour. To assess the ability of our model to be a general representation, three industrial polyurethane foams have been considered.

  20. In-store buying behaviour : memories of forgotten needs

    OpenAIRE

    Kanabar, Amrita Dilipkumar Ranchhod

    2012-01-01

    This study aims to better illustrate in-store buying behaviour, in terms of how different stimuli activate parts of shoppers’ brains to remember items that were not part of their shopping plans. The aim is to shed some light on shopper’s attitudes and reactions towards national brands or private labels, the impact of loyalty cards on cardholders’ shopping decisions, how shoppers with company behave differently than solo shoppers, and on the role of consumers’ hedonic and utilit...

  1. What Do We Really Know about Cognitive Inhibition? Task Demands and Inhibitory Effects across a Range of Memory and Behavioural Tasks.

    Directory of Open Access Journals (Sweden)

    Saima Noreen

    Full Text Available Our study explores inhibitory control across a range of widely recognised memory and behavioural tasks. Eighty-seven never-depressed participants completed a series of tasks designed to measure inhibitory control in memory and behaviour. Specifically, a variant of the selective retrieval-practice and the Think/No-Think tasks were employed as measures of memory inhibition. The Stroop-Colour Naming and the Go/No-Go tasks were used as measures of behavioural inhibition. Participants completed all 4 tasks. Task presentation order was counterbalanced across 3 separate testing sessions for each participant. Standard inhibitory forgetting effects emerged on both memory tasks but the extent of forgetting across these tasks was not correlated. Furthermore, there was no relationship between memory inhibition tasks and either of the main behavioural inhibition measures. At a time when cognitive inhibition continues to gain acceptance as an explanatory mechanism, our study raises fundamental questions about what we actually know about inhibition and how it is affected by the processing demands of particular inhibitory tasks.

  2. Attention and Emotion-Enhanced Memory: A Systematic Review and Meta-Analysis of Behavioural and Neuroimaging Evidence

    OpenAIRE

    Kohler, Mark; Cross, Zachariah; Santamaria, Amanda

    2018-01-01

    The interaction between attention and emotion is posited to influence long-term memory consolidation. We systematically reviewed experiments investigating the influence of attention on emotional memory to determine: (i) the reported effect of attention on memory for emotional stimuli, and (ii) whether there is homogeneity between behavioural and neuroimaging based effects. Over half of the 47 included experiments found a moderate-to-large effect of attention on emotional memory as measured be...

  3. Avoidance behaviour testing of Eisenia andrei in biodegradable plastic environment

    Directory of Open Access Journals (Sweden)

    Zuzana Tichá

    2013-01-01

    Full Text Available Avoidance behaviour test with the earthworms (ISO 17512-1:2008 is a rapid screening test for the evaluation of soil and the influence of pollutants and chemicals on the behaviour of earthworms. The purpose of the testing is to determine the avoidance behaviour of earthworm (in this case Eisenia andrei was used which can be used as an organism for the composting and occur naturally in soil environment. The methodology was modified according to the needs of the avoidance behaviour testing of earthworms in biodegradable plastic environment. It is a biodegradable thermoplastic material Mater-Bi, which is produced from corn starch. Californian earthworm (Eisenia andrei was chosen as a test organism. The two-chamber test was used in testing. 10 earthworms were used, which were exposed to a number of concentrations of the test substance, which was mixed into the compost environment. It was recorded both a positive result, avoidance reaction, as well as a negative result, non-avoidance reaction and also there was a case, where individuals prefer both substrates equally. Organisms showed no escape reaction and were fairly evenly distributed in both halves of the test vessel, it can be assessed that organisms prefer both substrates equally. In testing, the mortality was zero, none of the individuals died, at the conclusion of the test there were not found any dead individuals. Avoidance higher than 80 % didn’t occur; it cannot be said that the substrate is toxic or degraded.

  4. Unique and shared validity of the "Wechsler logical memory test", the "California verbal learning test", and the "verbal learning and memory test" in patients with epilepsy.

    Science.gov (United States)

    Helmstaedter, Christoph; Wietzke, Jennifer; Lutz, Martin T

    2009-12-01

    This study was set-up to evaluate the construct validity of three verbal memory tests in epilepsy patients. Sixty-one consecutively evaluated patients with temporal lobe epilepsy (TLE) or extra-temporal epilepsy (E-TLE) underwent testing with the verbal learning and memory test (VLMT, the German equivalent of the Rey auditory verbal learning test, RAVLT); the California verbal learning test (CVLT); the logical memory and digit span subtests of the Wechsler memory scale, revised (WMS-R); and testing of intelligence, attention, speech and executive functions. Factor analysis of the memory tests resulted in test-specific rather than test over-spanning factors. Parameters of the CVLT and WMS-R, and to a much lesser degree of the VLMT, were highly correlated with attention, language function and vocabulary. Delayed recall measures of logical memory and the VLMT differentiated TLE from E-TLE. Learning and memory scores off all three tests differentiated mesial temporal sclerosis from other pathologies. A lateralization of the epilepsy was possible only for a subsample of 15 patients with mesial TLE. Although the three tests provide overlapping indicators for a temporal lobe epilepsy or a mesial pathology, they can hardly be taken in exchange. The tests have different demands on semantic processing and memory organization, and they appear differentially sensitive to performance in non-memory domains. The tests capability to lateralize appears to be poor. The findings encourage the further discussion of the dependency of memory outcomes on test selection.

  5. Testing quantum behaviour at the macroscopic level

    International Nuclear Information System (INIS)

    Ghirardi, G.C.

    1994-07-01

    We reconsider recent proposals to test macro realism versus quantum mechanics in experiments involving noninvasive measurement processes on a Squid. In spite of the fact that we are able to prove that the proposed experiments do not represent a test of macro realism but simply of macroscopic quantum coherence we call attention to their extreme conceptual relevance. We also discuss some recent criticisms which have been raised against the considered proposal and we show that they are not relevant. (author). 12 refs

  6. Working memory and inattentive behaviour in a community sample of children

    Directory of Open Access Journals (Sweden)

    Lui Mariko

    2007-02-01

    Full Text Available Abstract Background Existing literature to date suggests a relationship between cognitive attention and working memory (WM, but the relationship between overt inattentive behaviour and WM is less clear. This study examined the relationship between WM and parent-rated inattentive behaviour in a community sample of 140 children aged 7–12 years. Methods Children completed 2 clinical (laboratory-based measures of WM (auditory-verbal and visual-spatial and a measure of real-life WM, designed specifically for this study, while their parents completed questionnaires about their child's inattentive behaviour and other areas of functioning. Results Findings indicated that poorer performance on WM tasks predicted inattentive behaviour. Conclusion These results are consistent with previous research linking WM deficits and poor attention in ADHD and normal populations. The present findings support a controlled attention model of WM.

  7. Testing for Short Memory in a VARMA Process

    OpenAIRE

    Oke, Timothy; Öller, Lars-Erik

    1997-01-01

    We generalize the short term memory test of an ARMA model, presented in Öller (1985), to the multivariate VARMA cases. In a study on Swedish exports and OECD demand we demonstrate how the multivariate setting extends the short memory.

  8. Testing for long memory in potentially nonstationary perturbed fractional processes

    DEFF Research Database (Denmark)

    Nielsen, Frank; Frederiksen, Per S.

    ¤er simulation results that show good size properties of the tests, with power against spurious long memory. An empirical study of daily log-squared returns series of exchange rates and DJIA30 stocks shows that indeed there is long memory in exchange rate volatility and stock return volatility....

  9. Computerized scoring algorithms for the Autobiographical Memory Test.

    Science.gov (United States)

    Takano, Keisuke; Gutenbrunner, Charlotte; Martens, Kris; Salmon, Karen; Raes, Filip

    2018-02-01

    Reduced specificity of autobiographical memories is a hallmark of depressive cognition. Autobiographical memory (AM) specificity is typically measured by the Autobiographical Memory Test (AMT), in which respondents are asked to describe personal memories in response to emotional cue words. Due to this free descriptive responding format, the AMT relies on experts' hand scoring for subsequent statistical analyses. This manual coding potentially impedes research activities in big data analytics such as large epidemiological studies. Here, we propose computerized algorithms to automatically score AM specificity for the Dutch (adult participants) and English (youth participants) versions of the AMT by using natural language processing and machine learning techniques. The algorithms showed reliable performances in discriminating specific and nonspecific (e.g., overgeneralized) autobiographical memories in independent testing data sets (area under the receiver operating characteristic curve > .90). Furthermore, outcome values of the algorithms (i.e., decision values of support vector machines) showed a gradient across similar (e.g., specific and extended memories) and different (e.g., specific memory and semantic associates) categories of AMT responses, suggesting that, for both adults and youth, the algorithms well capture the extent to which a memory has features of specific memories. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  10. Field testing for cosmic ray soft errors in semiconductor memories

    International Nuclear Information System (INIS)

    O'Gorman, T.J.; Ross, J.M.; Taber, A.H.; Ziegler, J.F.; Muhlfeld, H.P.; Montrose, C.J.; Curtis, H.W.; Walsh, J.L.

    1996-01-01

    This paper presents a review of experiments performed by IBM to investigate the causes of soft errors in semiconductor memory chips under field test conditions. The effects of alpha-particles and cosmic rays are separated by comparing multiple measurements of the soft-error rate (SER) of samples of memory chips deep underground and at various altitudes above the earth. The results of case studies on four different memory chips show that cosmic rays are an important source of the ionizing radiation that causes soft errors. The results of field testing are used to confirm the accuracy of the modeling and the accelerated testing of chips

  11. Miniature wireless recording and stimulation system for rodent behavioural testing

    Science.gov (United States)

    Pinnell, R. C.; Dempster, J.; Pratt, J.

    2015-12-01

    Objective. Elucidation of neural activity underpinning rodent behaviour has traditionally been hampered by the use of tethered systems and human involvement. Furthermore the combination of deep-brain stimulation (DBS) and various neural recording modalities can lead to complex and time-consuming laboratory setups. For studies of this type, novel tools are required to drive forward this research. Approach. A miniature wireless system weighing 8.5 g (including battery) was developed for rodent use that combined multichannel DBS and local-field potential (LFP) recordings. Its performance was verified in a working memory task that involved 4-channel fronto-hippocampal LFP recording and bilateral constant-current fimbria-fornix DBS. The system was synchronised with video-tracking for extraction of LFP at discrete task phases, and DBS was activated intermittently at discrete phases of the task. Main results. In addition to having a fast set-up time, the system could reliably transmit continuous LFP at over 8 hours across 3-5 m distances. During the working memory task, LFP pertaining to discrete task phases was extracted and compared with well-known neural correlates of active exploratory behaviour in rodents. DBS could be wirelessly activated/deactivated at any part of the experiment during EEG recording and transmission, allowing for a seamless integration of this modality. Significance. The wireless system combines a small size with a level of robustness and versatility that can greatly simplify rodent behavioural experiments involving EEG recording and DBS. Designed for versatility and simplicity, the small size and low-cost of the system and its receiver allow for enhanced portability, fast experimental setup times, and pave the way for integration with more complex behaviour.

  12. Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

    Directory of Open Access Journals (Sweden)

    Zahra Shahidipour

    2014-01-01

    Conclusion: Based on the obtained results, significant reduction in auditory memory was seen in aged group and the Persian version of dichotic auditory-verbal memory test, like many other auditory verbal memory tests, showed the aging effects on auditory verbal memory performance.

  13. Effects of repeated treatment with MDMA on working memory and behavioural flexibility in mice.

    Science.gov (United States)

    Viñals, Xavier; Maldonado, Rafael; Robledo, Patricia

    2013-03-01

    Repeated administration of 3,4-methylenedioxymethamphetamine (MDMA) produces dopaminergic neurotoxicity in mice. However, it is still not clear whether this exposure induces deficits in cognitive processing related to specific subsets of executive functioning. We evaluated the effects of neurotoxic and non-neurotoxic doses of MDMA (0, 3 and 30 mg/kg, twice daily for 4 days) on working memory and attentional set-shifting in mice, and changes in extracellular levels of dopamine (DA) in the striatum. Treatment with MDMA (30 mg/kg) disrupted performance of acquired operant alternation, and this impairment was still apparent 5 days after the last drug administration. Decreased alternation was not related to anhedonia because no differences were observed between groups in the saccharin preference test under similar experimental conditions. Correct responding on delayed alternation was increased 1 day after repeated treatment with MDMA (30 mg/kg), probably because of general behavioural quiescence. Notably, the high dose regimen of MDMA impaired attentional set-shifting related to an increase in total perseveration errors. Finally, basal extracellular levels of DA in the striatum were not modified in mice repeatedly treated with MDMA with respect to controls. However, an acute challenge with MDMA (10 mg/kg) failed to increase DA outflow in mice receiving the highest MDMA dose (30 mg/kg), corroborating a decrease in the functionality of DA transporters. Seven days after this treatment, the effects of MDMA on DA outflow were recovered. These results suggest that repeated neurotoxic doses of MDMA produce lasting impairments in recall of alternation behaviour and reduce cognitive flexibility in mice. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

  14. Testing the exclusivity effect in location memory.

    Science.gov (United States)

    Clark, Daniel P A; Dunn, Andrew K; Baguley, Thom

    2013-01-01

    There is growing literature exploring the possibility of parallel retrieval of location memories, although this literature focuses primarily on the speed of retrieval with little attention to the accuracy of location memory recall. Baguley, Lansdale, Lines, and Parkin (2006) found that when a person has two or more memories for an object's location, their recall accuracy suggests that only one representation can be retrieved at a time (exclusivity). This finding is counterintuitive given evidence of non-exclusive recall in the wider memory literature. The current experiment explored the exclusivity effect further and aimed to promote an alternative outcome (i.e., independence or superadditivity) by encouraging the participants to combine multiple representations of space at encoding or retrieval. This was encouraged by using anchor (points of reference) labels that could be combined to form a single strongly associated combination. It was hypothesised that the ability to combine the anchor labels would allow the two representations to be retrieved concurrently, generating higher levels of recall accuracy. The results demonstrate further support for the exclusivity hypothesis, showing no significant improvement in recall accuracy when there are multiple representations of a target object's location as compared to a single representation.

  15. Musical Ability and the Drake Music Memory Test

    Science.gov (United States)

    Griffin, Lawrence R.; Eisenman, Russell

    1972-01-01

    Results show that the Drake Music Memory Test should be able to discriminate between the poorest and strongest prospects for success in profiting from musical instruction, although it may not be particularly useful in individual counseling. (Authors)

  16. Memory Test Performance on Analogous Verbal and Nonverbal Memory Tests in Patients with Frontotemporal Dementia and Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Deanna Baldock

    2016-01-01

    Full Text Available Background: Patients with frontotemporal dementia (FTD typically have initial deficits in language or changes in personality, while the defining characteristic of Alzheimer's disease (AD is memory impairment. Neuropsychological findings in the two diseases tend to differ, but can be confounded by verbal impairment in FTD impacting performance on memory tests in these patients. Methods: Twenty-seven patients with FTD and 102 patients with AD underwent a neuropsychological assessment before diagnosis. By utilizing analogous versions of a verbal and nonverbal memory test, we demonstrated differences in these two modalities between AD and FTD. Discussion: Better differentiation between AD and FTD is found in a nonverbal memory test, possibly because it eliminates the confounding variable of language deficits found in patients with FTD. These results highlight the importance of nonverbal learning tests with multiple learning trials in diagnostic testing.

  17. Memory Test Performance on Analogous Verbal and Nonverbal Memory Tests in Patients with Frontotemporal Dementia and Alzheimer's Disease.

    Science.gov (United States)

    Baldock, Deanna; Miller, Justin B; Leger, Gabriel C; Banks, Sarah Jane

    2016-01-01

    Patients with frontotemporal dementia (FTD) typically have initial deficits in language or changes in personality, while the defining characteristic of Alzheimer's disease (AD) is memory impairment. Neuropsychological findings in the two diseases tend to differ, but can be confounded by verbal impairment in FTD impacting performance on memory tests in these patients. Twenty-seven patients with FTD and 102 patients with AD underwent a neuropsychological assessment before diagnosis. By utilizing analogous versions of a verbal and nonverbal memory test, we demonstrated differences in these two modalities between AD and FTD. Better differentiation between AD and FTD is found in a nonverbal memory test, possibly because it eliminates the confounding variable of language deficits found in patients with FTD. These results highlight the importance of nonverbal learning tests with multiple learning trials in diagnostic testing.

  18. The effect of taurine and enriched environment on behaviour, memory and hippocampus of diabetic rats.

    Science.gov (United States)

    Rahmeier, Francine Luciano; Zavalhia, Lisiane Silveira; Tortorelli, Lucas Silva; Huf, Fernanda; Géa, Luiza Paul; Meurer, Rosalva Thereza; Machado, Aryadne Cardoso; Gomez, Rosane; Fernandes, Marilda da Cruz

    2016-09-06

    Diabetes mellitus (DM) has been studied recently as a major cause of cognitive deficits, memory and neurodegenerative damage. Taurine and enriched environment have stood out for presenting neuroprotective and stimulating effects that deserve further study. In this paper, we examined the effects of taurine and enriched environment in the context of diabetes, evaluating effects on behaviour, memory, death and cellular activity. Eighty-eight Wistar rats were divided into 2 groups (E=enriched environment; C=standard housing). Some animals (24/group) underwent induction of diabetes, and within each group, some animals (half of diabetics (D) and half of non-diabetics (ND)/group) were treated for 30days with taurine (T). Untreated animals received saline (S). In total, there were eight subgroups: DTC, DSC, NDTC, NDSC, DTE, DSE, NDTE and NDSE. During the experiment, short-term memory was evaluated. After 30th day of experiment, the animals were euthanized and was made removal of brains used to immunohistochemistry procedures for GFAP and cleaved caspase-3. As a result, we observed that animals treated with taurine showed better performance in behavioural and memory tasks, and the enriched environment had positive effects, especially in non-diabetic animals. Furthermore, taurine and enriched environment seemed to be able to interfere with neuronal apoptosis and loss of glial cells, and in some instances, these two factors seemed to have synergistic effects. From these data, taurine and enriched environment may have important neurostimulant and neuroprotective effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Amsterdam Short-Term Memory test: a new procedure for the detection of feigned memory deficits

    NARCIS (Netherlands)

    Schagen, S.; Schmand, B.; de Sterke, S.; Lindeboom, J.

    1997-01-01

    The validity of two malingering tests, the newly developed Amsterdam Short-Term Memory (ASTM) test and the Distraction test (Baker, Hanley, Jackson, Kimmance, & Slade, 1993) was examined in a group of patients with closed-head injury (CHI), a normal control group, and a control group with

  20. HIV testing behaviour among heterosexual migrants in Amsterdam

    NARCIS (Netherlands)

    Stolte, I. G.; Gras, M.; van Benthem, B. H.; Coutinho, R. A.; van den Hoek, J. A. R.

    2003-01-01

    This cross-sectional study among heterosexual migrant groups in south-eastern Amsterdam, the city area where the largest migrant groups live, provides an insight into HIV testing behaviour in this particular group. Participants were recruited at street locations (May 1997-July 1998) and interviewed

  1. Memory testing in dementia: how much is enough?

    Science.gov (United States)

    Derrer, D S; Howieson, D B; Mueller, E A; Camicioli, R M; Sexton, G; Kaye, J A

    2001-01-01

    Analyses of eight widely used memory measures (Word List Acquisition and Recall used in the Alzheimer's Disease Assessment Scale and the Consortium to Establish a Registry for Alzheimer's Disease neuropsychology battery, Wechsler Memory Scale-Revised [WMS-R] Logical Memory I and II, WMS-R Visual Reproduction I and II, the memory scores from the Neurobehavioral Cognitive Status Examination [NCSE], memory scores from the Mini-Mental State Examination [MMSE]), and the MMSE total score showed each to have moderate predictive power in differentiating between patients with mild dementia and healthy normal controls. When these instruments were combined in a logistic regression analysis, three of them had substantial predictive power. Together, the Word List Acquisition, WMS-R Logical Memory II, and WMS-R Visual Reproduction II were 97.26% accurate (100% sensitive and 94.59% specific) in distinguishing these two groups. The Word List Acquisition is a brief test that alone had high accuracy (92%). These memory tests are highly useful in the diagnosis of mild dementia.

  2. Order information coding in working memory: Review of behavioural studies and cognitive mechanisms

    Directory of Open Access Journals (Sweden)

    Barbara Dolenc

    2014-06-01

    Full Text Available Executive processes, such as coding for sequential order, are of extreme importance for higher-order cognitive tasks. One of the significant questions is, how order information is coded in working memory and what cognitive mechanisms and processes mediate it. The aim of this review paper is to summarize results of studies that explore whether order and item memory are two separable processes. Furthermore, we reviewed evidence for each of the proposed cognitive mechanism that might mediate order processing. Previous behavioural and neuroimaging data suggest different representation and processing of item and order information in working memory. Both information are maintained and recalled separately and this separation seems to hold for recognition as well as for recall. To explain the result of studies of order coding, numerous cognitive mechanisms were proposed. We focused on four different mechanisms by which order information might be coded and retrieved, namely inter-item associations, direct coding, hierarchical coding and magnitude coding. Each of the mechanisms can explain some of the aspect of order information coding, however none of them is able to explain all of the empirical findings. Due to its complex nature it is not surprising that a single mechanism has difficulties accounting for all the behavioral data and order memory may be more accurately characterized as the result of a set of mechanisms rather than a single one. Moreover, the findings beget a question of whether different types of memory for order information might exist.

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

    Science.gov (United States)

    Zaitsu, Wataru

    2012-10-01

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

  4. A test of the survival processing advantage in implicit and explicit memory tests.

    Science.gov (United States)

    McBride, Dawn M; Thomas, Brandon J; Zimmerman, Corinne

    2013-08-01

    The present study was designed to investigate the survival processing effect (Nairne, Thompson, & Pandeirada, Journal of Experimental Psychology: Learning, Memory, and Cognition, 33, 263-273, 2007) in cued implicit and explicit memory tests. The survival effect has been well established in explicit free recall and recognition tests, but has not been evident in implicit memory tests or in cued explicit tests. In Experiment 1 of the present study, we tested implicit and explicit memory for words studied in survival, moving, or pleasantness contexts in stem completion tests. In Experiment 2, we further tested these effects in implicit and explicit category production tests. Across the two experiments, with four separate memory tasks that included a total of 525 subjects, no survival processing advantage was found, replicating the results from implicit tests reported by Tse and Altarriba (Memory & Cognition, 38, 1110-1121, 2010). Thus, although the survival effect appears to be quite robust in free recall and recognition tests, it has not been replicated in cued implicit and explicit memory tests. The similar results found for the implicit and explicit tests in the present study do not support encoding elaboration explanations of the survival processing effect.

  5. Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

    OpenAIRE

    Zahra Shahidipour; Ahmad Geshani; Zahra Jafari; Shohreh Jalaie; Elham Khosravifard

    2014-01-01

    Background and Aim: Memory is one of the aspects of cognitive function which is widely affected among aged people. Since aging has different effects on different memorial systems and little studies have investigated auditory-verbal memory function in older adults using dichotic listening techniques, the purpose of this study was to evaluate the auditory-verbal memory function among old people using Persian version of dichotic auditory-verbal memory test. Methods: The Persian version of dic...

  6. Roles for the subiculum in spatial information processing, memory, motivation and the temporal control of behaviour.

    Science.gov (United States)

    O'Mara, Shane M; Sanchez-Vives, Maria V; Brotons-Mas, Jorge R; O'Hare, Eugene

    2009-08-01

    The subiculum is in a pivotal position governing the output of the hippocampal formation. Despite this, it is a rather under-explored and sometimes ignored structure. Here, we discuss recent data indicating that the subiculum participates in a wide range of neurocognitive functions and processes. Some of the functions of subiculum are relatively well-known-these include providing a relatively coarse representation of space and participating in, and supporting certain aspects of, memory (particularly in the dynamic bridging of temporal intervals). The subiculum also participates in a wide variety of other neurocognitive functions too, however. Much less well-known are roles for the subiculum, and particularly the ventral subiculum, in the response to fear, stress and anxiety, and in the generation of motivated behaviour (particularly the behaviour that underlies drug addiction and the response to reward). There is an emerging suggestion that the subiculum participates in the temporal control of behaviour. It is notable that these latter findings have emerged from a consideration of instrumental behaviour using operant techniques; it may well be the case that the use of the watermaze or similar spatial tasks to assess subicular function (on the presumption that its functions are very similar to the hippocampus proper) has obscured rather than revealed neurocognitive functions of subiculum. The anatomy of subiculum suggests it participates in a rather subtle fashion in a very broad range of functions, rather than in a relatively more isolated fashion in a narrower range of functions, as might be the case for "earlier" components of hippocampal circuitry, such as the CA1 and CA3 subfields. Overall, there appears to a strong dorso-ventral segregation of function within subiculum, with the dorsal subiculum relatively more concerned with space and memory, and the ventral hippocampus concerned with stress, anxiety and reward. Finally, it may be the case that the whole

  7. Behaviour of tail-docked lambs tested in isolation

    Directory of Open Access Journals (Sweden)

    Marchewka Joanna

    2016-12-01

    Full Text Available The aims of the current study were to detect behavioural indicators of pain of tail-docked sheep tested in isolation and to determine the relationship between behaviour and the pain levels to which they were exposed. Twenty-four female lambs, randomly assigned to four pens, had their tail docked with a rubber ring (TD; n = 6 without pain control procedures, TD with anaesthesia (TDA; n = 6 or TD with anaesthesia and analgesia (TDAA; n = 6. Additionally, six lambs handled but without tail docking or application of pain relief measures were used as the control (C. On the day prior (Day –1 to the TD and on days 1, 3 and 5 post-procedure, each lamb was individually removed from its group and underwent a 2.5 min open field test in a separate pen. Frequencies of behaviours such as rest, running, standing, walking and exploring were directly observed. Frequencies of exploratory climbs (ECs and abrupt climbs (ACs over the testing pen’s walls were video-recorded. Data were analysed using generalised linear mixed models with repeated measurements, including treatment and day as fixed effects and behaviour on Day –1 as a linear covariate. Control and TDAA lambs stood more frequently than TD lambs. TD lambs performed significantly more ACs compared to all other treatment groups. No other treatment effects were detected. A day effect was detected for all behaviours, while the EC frequency was highest for all tail-docked lambs on Day 5. Findings suggest that standing, ACs and ECs could be used as potential indicators of pain in isolated tail-docked lambs. However, differences in ECs between treatments only appeared 3 d after tail docking.

  8. Assessment of Prospective Memory – a Validity Study of Memory for Intentions Screening Test

    NARCIS (Netherlands)

    Bezdicek, O.; Raskin, S.A.; Altgassen, A.M.; Ruzicka, E.

    2014-01-01

    Aim: The goal of the present study was to validate the Czech version of the Memory for Intentions (Screening) Test (MIST, 2010). We included standardized testing material, translation of administration and scoring, and assessment of normative data for the MIST in the Czech population. Introduction:

  9. Memory detection 2.0: the first web-based memory detection test.

    Science.gov (United States)

    Kleinberg, Bennett; Verschuere, Bruno

    2015-01-01

    There is accumulating evidence that reaction times (RTs) can be used to detect recognition of critical (e.g., crime) information. A limitation of this research base is its reliance upon small samples (average n = 24), and indications of publication bias. To advance RT-based memory detection, we report upon the development of the first web-based memory detection test. Participants in this research (Study1: n = 255; Study2: n = 262) tried to hide 2 high salient (birthday, country of origin) and 2 low salient (favourite colour, favourite animal) autobiographical details. RTs allowed to detect concealed autobiographical information, and this, as predicted, more successfully so than error rates, and for high salient than for low salient items. While much remains to be learned, memory detection 2.0 seems to offer an interesting new platform to efficiently and validly conduct RT-based memory detection research.

  10. Memory detection 2.0: the first web-based memory detection test.

    Directory of Open Access Journals (Sweden)

    Bennett Kleinberg

    Full Text Available There is accumulating evidence that reaction times (RTs can be used to detect recognition of critical (e.g., crime information. A limitation of this research base is its reliance upon small samples (average n = 24, and indications of publication bias. To advance RT-based memory detection, we report upon the development of the first web-based memory detection test. Participants in this research (Study1: n = 255; Study2: n = 262 tried to hide 2 high salient (birthday, country of origin and 2 low salient (favourite colour, favourite animal autobiographical details. RTs allowed to detect concealed autobiographical information, and this, as predicted, more successfully so than error rates, and for high salient than for low salient items. While much remains to be learned, memory detection 2.0 seems to offer an interesting new platform to efficiently and validly conduct RT-based memory detection research.

  11. Free recall behaviour in children with and without spelling impairment: the impact of working memory subcapacities.

    Science.gov (United States)

    Malstädt, Nadine; Hasselhorn, Marcus; Lehmann, Martin

    2012-11-01

    This study examined supraspan free recall in children with and without spelling impairment. A repeated free recall task involving overt rehearsal and three computer-based adaptive working memory tasks were administered to 54 eight-year-old children. Children without spelling impairments tended to recall more items than did those children with spelling deficits. Video analyses revealed that recall behaviour was similar in impaired and unimpaired children, indicating that both groups applied similar learning activities. Group differences in number of recalled items were attributed to differences in working memory subcapacities between children with and without spelling impairment, especially with regard to central executive and phonological loop functioning. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Neonatal exposure to polybrominated diphenyl ether (PBDE 153) disrupts spontaneous behaviour, impairs learning and memory, and decreases hippocampal cholinergic receptors in adult mice

    International Nuclear Information System (INIS)

    Viberg, Henrik; Fredriksson, Anders; Eriksson, Per

    2003-01-01

    Neonatal exposure to polybrominated diphenyl ether (PBDE 153) disrupts spontaneous behaviour, impairs learning and memory, and decreases hippocampal cholinergic receptors in adult mice. Flame retardants are used to suppress or inhibit combustion processes in an effort to reduce the risk of fire. One class of flame retardants, polybrominated diphenyl ethers (PBDEs), are present and increasing in the environment and in human milk. The present study shows that neonatal exposure to 2,2',4,4',5,5'-hexaBDE (PBDE 153), a PBDE persistent both in environment and in human milk, can induce developmental neurotoxic effects, such as changes in spontaneous behaviour (hyperactivity), impairments in learning and memory, and reduced amounts of nicotinic receptors, effects that get worse with age. Neonatal NMRI male mice were orally exposed on day 10 to 0.45, 0.9, or 9.0 mg of PBDE 153/kg of body weight. Spontaneous behaviour (locomotion, rearing, and total activity) was observed in 2-, 4-, and 6-month-old mice, Morris water maze at an age of 6 months. The behaviour tests showed that the effects were dose-response and time-response related. Animals showing defects in learning and memory also showed significantly reduced amounts of nicotinic receptors in hippocampus, using α-bungarotoxin binding assay. The observed developmental neurotoxic effects seen for PBDE 153 are similar to those seen for PBDE 99 and for certain PCBs. Furthermore, PBDEs appear to as potent as the PCBs

  13. Going beyond audit and feedback: towards behaviour-based interventions to change physician laboratory test ordering behaviour.

    Science.gov (United States)

    Meidani, Z; Mousavi, G A; Kheirkhah, D; Benar, N; Maleki, M R; Sharifi, M; Farrokhian, A

    2017-12-01

    Studies indicate there are a variety of contributing factors affecting physician test ordering behaviour. Identifying these behaviours allows development of behaviour-based interventions. Methods Through a pilot study, the list of contributing factors in laboratory tests ordering, and the most ordered tests, were identified, and given to 50 medical students, interns, residents and paediatricians in questionnaire form. The results showed routine tests and peer or supervisor pressure as the most influential factors affecting physician ordering behaviour. An audit and feedback mechanism was selected as an appropriate intervention to improve physician ordering behaviour. The intervention was carried out at two intervals over a three-month period. Findings There was a large reduction in the number of laboratory tests ordered; from 908 before intervention to 389 and 361 after first and second intervention, respectively. There was a significant relationship between audit and feedback and the meaningful reduction of 7 out of 15 laboratory tests including complete blood count (p = 0.002), erythrocyte sedimentation rate (p = 0.01), C-reactive protein (p = 0.01), venous blood gas (p = 0.016), urine analysis (p = 0.005), blood culture (p = 0.045) and stool examination (p = 0.001). Conclusion The audit and feedback intervention, even in short duration, affects physician ordering behaviour. It should be designed in terms of behaviour-based intervention and diagnosis of the contributing factors in physicians' behaviour. Further studies are required to substantiate the effectiveness of such behaviour-based intervention strategies in changing physician behaviour.

  14. Pigeons exhibit higher accuracy for chosen memory tests than for forced memory tests in duration matching-to-sample.

    Science.gov (United States)

    Adams, Allison; Santi, Angelo

    2011-03-01

    Following training to match 2- and 8-sec durations of feederlight to red and green comparisons with a 0-sec baseline delay, pigeons were allowed to choose to take a memory test or to escape the memory test. The effects of sample omission, increases in retention interval, and variation in trial spacing on selection of the escape option and accuracy were studied. During initial testing, escaping the test did not increase as the task became more difficult, and there was no difference in accuracy between chosen and forced memory tests. However, with extended training, accuracy for chosen tests was significantly greater than for forced tests. In addition, two pigeons exhibited higher accuracy on chosen tests than on forced tests at the short retention interval and greater escape rates at the long retention interval. These results have not been obtained in previous studies with pigeons when the choice to take the test or to escape the test is given before test stimuli are presented. It appears that task-specific methodological factors may determine whether a particular species will exhibit the two behavioral effects that were initially proposed as potentially indicative of metacognition.

  15. Development and psychometric validation of the verbal affective memory test

    DEFF Research Database (Denmark)

    Jensen, Christian Gaden; Hjordt, Liv V; Stenbæk, Dea S

    2015-01-01

    . Furthermore, larger seasonal decreases in positive recall significantly predicted larger increases in depressive symptoms. Retest reliability was satisfactory, rs ≥ .77. In conclusion, VAMT-24 is more thoroughly developed and validated than existing verbal affective memory tests and showed satisfactory...... psychometric properties. VAMT-24 seems especially sensitive to measuring positive verbal recall bias, perhaps due to the application of common, non-taboo words. Based on the psychometric and clinical results, we recommend VAMT-24 for international translations and studies of affective memory.......We here present the development and validation of the Verbal Affective Memory Test-24 (VAMT-24). First, we ensured face validity by selecting 24 words reliably perceived as positive, negative or neutral, respectively, according to healthy Danish adults' valence ratings of 210 common and non...

  16. Test-retest reliability and validity of the Sniffin' TOM odor memory test.

    Science.gov (United States)

    Croy, Ilona; Zehner, Cora; Larsson, Maria; Zucco, Gesualdo M; Hummel, Thomas

    2015-03-01

    Few attempts have been made to develop an olfactory test that captures episodic retention of olfactory information. Assessment of episodic odor memory is of particular interest in aging and in the cognitively impaired as both episodic memory deficits and olfactory loss have been targeted as reliable hallmarks of cognitive decline and impending dementia. Here, 96 healthy participants (18-92 years) and an additional 19 older people with mild cognitive impairment were tested (73-82 years). Participants were presented with 8 common odors with intentional encoding instructions that were followed by a yes-no recognition test. After recognition completion, participants were asked to identify all odors by means of free or cued identification. A retest of the odor memory test (Sniffin' TOM = test of odor memory) took place 17 days later. The results revealed satisfactory test-retest reliability (0.70) of odor recognition memory. Both recognition and identification performance were negatively affected by age and more pronounced among the cognitively impaired. In conclusion, the present work presents a reliable, valid, and simple test of episodic odor recognition memory that may be used in clinical groups where both episodic memory deficits and olfactory loss are prevalent preclinically such as Alzheimer's disease. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Memory and metamemory performance in Alzheimer's disease and healthy elderly: the Contextual Memory Test (CMT).

    Science.gov (United States)

    Gil, N; Josman, N

    2001-08-01

    The purpose of the present study was to examine the ability of the Contextual Memory Test (CMT) to differentiate between elderly people suffering from Alzheimer's disease (AD) in comparison to healthy elderly people. Specifically, the objectives were to compare for differences between and within the groups on components of memory, including immediate and delayed recall as well as recognition. In addition, parameters of metamemory skills, such as general awareness, self-prediction of memory capacity, self-estimation, strategy use and use of contextual information, as well as the correlation between self-awareness and actual performance in both groups, were investigated. The sample consisted of 60 elderly participants, including 30 people diagnosed with AD who were assigned to the research group and 30 people matched for age, gender and educational level who were assigned to the control group. The results provide support for the hypothesis positing differences in memory performance between healthy elderly participants and those suffering from AD, particularly in immediate and delayed recall as well as in recognition. Moreover, findings indicate an improvement in memory performance under the cued condition (contextual), whereas improvement in the AD group proved to be significant only for immediate recall. The findings point to a distinct overestimation of memory ability predicted by both the AD and control groups. Following the memory task, however, the participants accurately estimated the number of items they remembered. In addition, significant correlations between the use of contextual and association strategies and the number of items remembered by both groups were obtained, in immediate as well as in delayed recall. Therefore, these findings support the CMT as a valuable memory and metamemory assessment tool for use with the AD population.

  18. Shattered illusions: the effect of explicit memory mediation on an indirect memory test.

    Science.gov (United States)

    Gooding, P A; Mayes, A R; Meudell, P R

    1999-05-01

    Four experiments were conducted to explore the possible involvement of explicit memory in an indirect memory test in which white noise accompanying old sentences was judged to be quieter than white noise accompanying new sentences (Jacoby, Allan, Collins & Larwill, 1988). Experiment 1 established that this effect lasted up to 1 week. Experiment 2 found that a group of amnesic patients showed a noise effect that was marginally above chance and not significantly less that that of their matched controls after a delay of one day. Effect of time pressure at test (Experiment 3) and divided attention at study (Experiment 4) suggested that the memory processes mediating the noise effect were not automatic, although the possibility that the processes involve enhanced fluency is also discussed.

  19. Ethnicity and HIV risk behaviour, testing and knowledge in Guatemala.

    Science.gov (United States)

    Taylor, Tory M; Hembling, John; Bertrand, Jane T

    2015-01-01

    To describe levels of risky sexual behaviour, HIV testing and HIV knowledge among men and women in Guatemala by ethnic group and to identify adjusted associations between ethnicity and these outcomes. Data on 16,205 women aged 15-49 and 6822 men aged 15-59 from the 2008-2009 Encuesta Nacional de Salud Materno Infantil were used to describe ethnic group differences in sexual behaviour, HIV knowledge and testing. We then controlled for age, education, wealth and other socio-demographic factors in a multivariate logistic regression model to examine the effects of ethnicity on outcomes related to age at sexual debut, number of lifetime sex partners, comprehensive HIV knowledge, HIV testing and lifetime sex worker patronage (men only). The data show low levels of risky sexual behaviour and low levels of HIV knowledge among indigenous women and men, compared to other respondents. Controlling for demographic factors, indigenous women were more likely than other women never to have been tested for HIV and to lack comprehensive HIV knowledge. They were less likely to report early sexual debut and three or more lifetime sexual partners. Indigenous men were more likely than other men to lack comprehensive HIV knowledge and demonstrated lower odds of early sexual debut, 10 or more lifetime sexual partners and sex worker patronage. The Mayan indigenous population in Guatemala, while broadly socially vulnerable, does not appear to be at elevated risk for HIV based on this analysis of selected risk factors. Nonetheless, low rates of HIV knowledge and testing may be cause for concern. Programmes working in indigenous communities should focus on HIV education and reducing barriers to testing. Further research into the factors that underlie ethnic self-identity and perceived ethnicity could help clarify the relative significance of these measures for HIV risk and other health outcomes.

  20. Pressure test behaviour of embalse nuclear power plant containment structure

    International Nuclear Information System (INIS)

    Bruschi, S.; Marinelli, C.

    1984-01-01

    It's described the structural behaviour of the containment structure during the pressure test of the Embalse plant (CANDU type, 600MW), made of prestressed concrete with an epoxi liner. Displacement, strain, temperature, and pressure measurements of the containment structure of the Embalse Nuclear Power Plant are presented. The instrumentation set up and measurement specifications are described for all variables of interest before, during and after the pressure test. The analytical models to simulate the heat transfer due to sun heating and air convenction and to predict the associated thermal strains and displacements are presented. (E.G.) [pt

  1. Predicting entrepreneurial behaviour: A test of the theory of planned behaviour

    NARCIS (Netherlands)

    Kautonen, T.; van Gelderen, M.W.; Fink, M.

    2013-01-01

    This article contributes to the occupational choice literature pertaining to entrepreneurship by applying the Theory of Planned Behaviour (TPB) to predict entrepreneurial behaviour. Originating from social psychology, the TPB posits that intention, a function of behavioural beliefs, is a significant

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

    Science.gov (United States)

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

    2017-01-01

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

  3. Group Differences in Test-Taking Behaviour: An Example from a High-Stakes Testing Program

    Science.gov (United States)

    Stenlund, Tova; Eklöf, Hanna; Lyrén, Per-Erik

    2017-01-01

    This study investigated whether different groups of test-takers vary in their reported test-taking behaviour in a high-stakes test situation. A between-group design (N = 1129) was used to examine whether high and low achievers, as well as females and males, differ in their use of test-taking strategies, and in level of reported test anxiety and…

  4. Episodic, generalized, and semantic memory tests: switching and strength effects.

    Science.gov (United States)

    Humphreys, Michael S; Murray, Krista L

    2011-09-01

    We continue the process of investigating the probabilistic paired associate paradigm in an effort to understand the memory access control processes involved and to determine whether the memory structure produced is in transition between episodic and semantic memory. In this paradigm two targets are probabilistically paired with a cue across a large number of short lists. Participants can recall the target paired with the cue in the most recent list (list specific test), produce the first of the two targets that have been paired with that cue to come to mind (generalised test), and produce a free association response (semantic test). Switching between a generalised test and a list specific test did not produce a switching cost indicating a general similarity in the control processes involved. In addition, there was evidence for a dissociation between two different strength manipulations (amount of study time and number of cue-target pairings) such that number of pairings influenced the list specific, generalised and the semantic test but amount of study time only influenced the list specific and generalised test. © 2011 Canadian Psychological Association

  5. Tests and calculation of the seismic behaviour of concrete structures

    International Nuclear Information System (INIS)

    Gauvain, J.; Hoffman, A.; Jeandidier, C.; Livolant, M.

    1979-01-01

    This paper deals with the frame type buildings, which are generally the most sensible to earthquakes. Its objectives are to describe the main phenomena governing the behaviour of such structures, when the earthquake level increases up to the structure collapse, to point out what type of calculation model shall be used to obtain good results and to give an estimation of the safety factors corresponding to the usual design practice. Extended experimental research on the behaviour of reinforced concrete beams and frames submitted to monotonic or cyclic loading has been done. These tests are very useful to build constitutive laws models, but as they do not reproduce the earthquake loads, they do not simulate directly what happens to the structure during an earthquake. For that reason, since 1966, dynamics tests were performed using vibration generators or shaking-tables. As an example of that type of test and of the corresponding results, we describe here with more details the tests made at the Saclay Center, on a shaking-table called VESUVE, on simple beams and frames

  6. Reduced Capacity in a Dichotic Memory Test for Adult Patients with ADHD

    Science.gov (United States)

    Dige, Niels; Maahr, Eija; Backenroth-Ohsako, Gunnel

    2010-01-01

    Objective: To evaluate whether a dichotic memory test would reveal deficits in short-term working-memory recall and long-term memory recall in a group of adult patients with ADHD. Methods: A dichotic memory test with ipsilateral backward speech distraction in an adult ADHD group (n = 69) and a control group (n = 66) is used to compare performance…

  7. Children's memories of removal: a test of attachment theory.

    Science.gov (United States)

    Melinder, Annika; Baugerud, Gunn Astrid; Ovenstad, Kristianne Stigsdatter; Goodman, Gail S

    2013-02-01

    We report a study of parents' attachment orientations and children's autobiographical memory for an experience that according to Bowlby's (1982) attachment theory should be particularly threatening-children's forced separation from their parents. It was hypothesized that individual differences in parents' attachment orientations would be associated with children's distress and memory for this highly traumatic event. Children (n = 28) were observed during forced removal from home or school by Child Protective Services due to allegations of child maltreatment. Children's memory for the removal was tested 1 week later, and biological parents (n = 28) completed an adult attachment measure. Parental attachment anxiety significantly predicted children's distress during less stressful phases of the removal, R(2) = .25, and parents' attachment-related avoidance predicted fewer correct memory reports from the children (i.e., fewer hits to open-ended questions, R(2) = .16, and fewer hits to direct questions, R(2) = .27). The findings indicate that attachment theory provides important guidance for understanding children's autobiographical memory for traumatic events. Copyright © 2013 International Society for Traumatic Stress Studies.

  8. Robust memory of where from way back when: evidence from behaviour and visual attention.

    Science.gov (United States)

    Bauer, Patricia J; Stewart, Rebekah; Sirkin, Ruth E; Larkina, Marina

    2017-09-01

    Retention of events typically exhibits a sharp initial decrease followed by levelling off of forgetting. In an apparent exception to this general rule, college students have robust memory for their own locations in obscured versions of photographs of their entering classes taken during orientation-related activities, whether tested 2 months or 42 months after the event. Experiment 1 of the present research was a test for conceptual replication of this finding in photographs depicting more than twice the number of students (and thus potential distracters). There was no difference in memory accuracy for personal spatial location across retention intervals of 6-30 months. Experiment 2 featured 40-h and 2-month retention intervals, thereby providing a more fine-grained test of the forgetting function. The findings replicated Experiment 1. In Experiment 3, eye-tracking measures of visual attention revealed that participants rapidly fixated their own spatial locations within the photographs, even in the absence of explicit awareness. In all three experiments, memory for temporal features of the orientation activities (e.g., day and time the photograph was taken) followed the typical forgetting function. The findings suggest differential preservation of episodic memory for where relative to other aspects of events and experiences, such as when.

  9. The nitric oxide donor sodium nitroprusside attenuates recognition memory deficits and social withdrawal produced by the NMDA receptor antagonist ketamine and induces anxiolytic-like behaviour in rats.

    Science.gov (United States)

    Trevlopoulou, Aikaterini; Touzlatzi, Ntilara; Pitsikas, Nikolaos

    2016-03-01

    Experimental evidence indicates that the non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist ketamine impairs cognition and can mimic certain aspects of positive and negative symptoms of schizophrenia in rodents. Nitric oxide (NO) is considered as an intracellular messenger in the brain, and its abnormalities have been linked to schizophrenia. The present study was designed to investigate the ability of the NO donor sodium nitroprusside (SNP) to counteract schizophrenia-like behavioural deficits produced by ketamine in rats. The ability of SNP to reverse ketamine-induced memory deficits and social withdrawal were assessed using the novel object recognition task (NORT) and the social interaction test, respectively. Furthermore, since anxiety disorders are noted to occur commonly in schizophrenics, the effects of SNP on anxiety-like behaviour were examined using the light/dark test. Locomotor activity was also assessed as an independent measure of the potential motoric effects of this NO donor. SNP (0.3 and 1 mg/kg) reversed ketamine (3 mg/kg)-induced short-term recognition memory deficits. SNP (1 mg/kg) counteracted the ketamine (8 mg/kg)-induced social isolation in the social interaction test. The anxiolytic-like effects in the light/dark test of SNP (1 mg/kg) cannot be attributed to changes in locomotor activity. Our findings illustrate a functional interaction between the nitrergic and glutamatergic system that may be of relevance for schizophrenia-like behavioural deficits. The data also suggest a role of NO in anxiety.

  10. Influence of Silver nanoparticles addition on the phase transformation, mechanical properties and corrosion behaviour of Cu–Al–Ni shape memory alloys

    Energy Technology Data Exchange (ETDEWEB)

    Saud, Safaa N.; Hamzah, E., E-mail: esah@fkm.utm.my; Abubakar, T.; Bakhsheshi-Rad, H.R.; Farahany, S.; Abdolahi, A.; Taheri, M.M.

    2014-11-05

    Highlights: • Thermal analysis showed four different phase β, α, NiAl and γ2 during solidification. • The martensite appeared in the microstructure as a plate and needle like shape. • Shape recovery ratio of 80% was obtained after Ag nanoparticles addition. • Effect of Ag nanoparticles on the corrosion behaviour of Cu–Al–Ni SMA was investigated. - Abstract: Incorporation of silver nanoparticles into Cu-based shape memory alloys is recommended to enhance their phase transformation behaviour. However, this incorporation can affect their transformation temperatures, mechanical, microstructural and corrosion characteristics. Four different phase reactions β, α, NiAl and γ{sub 2} were detected on a derivative curve during the solidification by-computer-aided cooling curve thermal analysis. The highest fraction solid (82%) was calculated for the parent phase (β) based on the Newtonian baseline method. The microstructural changes and mechanical properties were investigated using field emission scanning electron microscopy, X-ray diffraction tensile test and shape memory effect test. It was found that the addition of Ag can control the phase morphology and orientations along with the formation of the Ag-rich precipitates, and thus the tensile strength, elongation, fracture stress–strain, yield strength and shape memory effect are improved. Remarkably, the shape recovery ratio reached approximately 80% of the original shape. The corrosion behaviour of the Cu–Al–Ni shape memory alloy were investigated using electrochemical tests in NaCl solution and their results showed that the corrosion potential (E{sub corr}) of Cu–Al–Ni SMA is shifted towards the nobler direction from −307.4 to −277.1 m V{sub SCE} with the addition of 0.25 wt.% Ag.

  11. Sucrose or sucrose and caffeine differentially impact memory and anxiety-like behaviours, and alter hippocampal parvalbumin and doublecortin.

    Science.gov (United States)

    Xu, Tanya J; Reichelt, Amy C

    2018-04-11

    Caffeinated sugar-sweetened "energy" drinks are a subset of soft drinks that are popular among young people worldwide. High sucrose diets impair cognition and alter aspects of emotional behaviour in rats, however, little is known about sucrose combined with caffeine. Rats were allocated to 2 h/day 10% sucrose (Suc), 10% sucrose plus 0.04% caffeine (CafSuc) or control (water) conditions. The addition of caffeine to sucrose appeared to increase the rewarding aspect of sucrose, as the CafSuc group consumed more solution than the Suc group. After 14 days of intermittent Suc or CafSuc access, anxiety was assessed in the elevated plus maze (EPM) prior to their daily solution access, whereby CafSuc and Suc rats spent more time in the closed arms, indicative of increased anxiety. Following daily solution access, CafSuc, but not Suc, rats showed reduced anxiety-like behaviour in the open-field. Control and CafSuc rats displayed intact place and long-term object memory, while Suc showed impaired memory performance. Sucrose reduced parvalbumin immunoreactivity in the hippocampus, but no differences were observed between Control and CafSuc conditions. Parvalbumin reactivity in the basolateral amygdala did not differ between conditions. Reduced doublecortin immunoreactivity in the dentate gyrus relative to controls was seen in the CafSuc, but not Suc, treatment conditions. These findings indicate that the addition of caffeine to sucrose attenuated cognitive deficits. However, the addition of caffeine to sucrose evoked anxiety-like responses under certain testing conditions, suggesting that frequent consumption of caffeinated energy drinks may promote emotional alterations and brain changes compared to standard soft drinks. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. WORKING MEMORY CAPACITY TEST REVEALS SUBJECTS DIFFICULTIES MANAGING LIMITED CAPACITY

    Directory of Open Access Journals (Sweden)

    R V Ershova

    2016-12-01

    Full Text Available Free recall consists of two separate stages: the emptying of working memory and reactivation [5]. The Tarnow Unchunkable Test (TUT, [7] uses double integer items to separate out only the first stage by making it difficult to reactivate items due to the lack of intra-item relationships.193 Russian college students were tested via the internet version of the TUT. The average number of items remembered in the 3 item test was 2.54 items. In the 4 item test, the average number of items decreased to 2.38. This, and a number of other qualitative distribution differences between the 3 and 4 item tests, indicate that the average capacity limit of working memory has been reached at 3 items. This provides the first direct measurement of the unchunkable capacity limit of number items.Difficulties in managing working memory occurred as most subjects remembered less as the number of items increased beyond capacity and failed to remember a single item in at least one out of three 4 item trials. The Pearson correlation between the total recall of 3 and 4 items was a small 38%.

  13. Aging and memory: corrections for age, sex and education for three widely used memory tests.

    Science.gov (United States)

    Zappalà, G; Measso, G; Cavarzeran, F; Grigoletto, F; Lebowitz, B; Pirozzolo, F; Amaducci, L; Massari, D; Crook, T

    1995-04-01

    The associate learning subtest from the Wechsler Memory Scale; Benton's Visual Retention test and a Controlled Word Association Task (FAS) were administered to a random sample of normal, healthy individuals whose age ranged from 20 to 79 years, recruited within the Italian peninsula. The neuropsychological examination took place on a mobile unit and the tests were given by the same team of neuropsychologists to reduce variability among examiners. The Research Project was known as Progetto Memoria. Corrections to the scores of these tests were calculated for age, sex, and education. These corrected values will allow clinicians to screen for memory impairment with greater precision among normally aging individuals, thus improving differential diagnosis between physiologic and pathologic deterioration of cognitive functions.

  14. Memory for emotional events: The role of time of testing and type of test

    Directory of Open Access Journals (Sweden)

    Priscila Goergen Brust

    2012-03-01

    Full Text Available The impact of emotion on memory performance is widely debated in the scientific literature. In the present paper, the relation between emotion and memory was addressed in three experiments using the Slideshow Procedure. In the first experiment, 128 participants’ memory was tested for one of two versions of the Procedure (arousal or neutral through free recall. In the second experiment, 75 participants were asked to recall the information of the arousal version immediately after or one week after watching it. In the third experiment, 75 participants watched the arousal version and answered either a free recall or a recognition test one week after. The results suggested that memory for arousal events is better when tested immediately after the stimuli using free recall.

  15. HIV testing behaviour among heterosexual migrants in Amsterdam.

    Science.gov (United States)

    Stolte, I G; Gras, M; Van Benthem, B H; Coutinho, R A; van den Hoek, J A

    2003-08-01

    This cross-sectional study among heterosexual migrant groups in south-eastern Amsterdam, the city area where the largest migrant groups live, provides an insight into HIV testing behaviour in this particular group. Participants were recruited at street locations (May 1997-July 1998) and interviewed using structured questionnaires. They also donated saliva for HIV testing. In total, 705 males and 769 females were included in this study (Afro-Surinamese (45%), Dutch-Antilleans (15%) and West Africans (40%)). Prior HIV testing was reported by 38% of all migrants (556/1479), of which only a minority (28%) had actively requested HIV testing. Multivariate logistic regression showed that not actively requesting HIV testing was more likely among younger (migrants, especially women (ORwomen: 4.79, p risk should be facilitated by promoting HIV testing and by improving accurate self-assessment of risk for HIV infection, especially among the groups that do not actively request HIV testing. This would increase HIV awareness and provide the opportunity of better medical care earlier in HIV infection.

  16. LEARNING AND MEMORY TESTS IN DEVELOPMENTAL NEUROTOXICITY TESTING: A CROSS-LABORATORY COMPARISON OF CONTROL DATA.

    Science.gov (United States)

    The US EPA Developmental Neurotoxicity (DNT) Study Test Guideline (OPPTS 870.6300) calls for functional tests to assess the impact of chemicals on cognitive function in offspring following maternal exposure. A test of associative learning and memory is to be conducted around th...

  17. Coverage of the Test of Memory Malingering, Victoria Symptom Validity Test, and Word Memory Test on the Internet: is test security threatened?

    Science.gov (United States)

    Bauer, Lyndsey; McCaffrey, Robert J

    2006-01-01

    In forensic neuropsychological settings, maintaining test security has become critically important, especially in regard to symptom validity tests (SVTs). Coaching, which can entail providing patients or litigants with information about the cognitive sequelae of head injury, or teaching them test-taking strategies to avoid detection of symptom dissimulation has been examined experimentally in many research studies. Emerging evidence supports that coaching strategies affect psychological and neuropsychological test performance to differing degrees depending on the coaching paradigm and the tests administered. The present study sought to examine Internet coverage of SVTs because it is potentially another source of coaching, or information that is readily available. Google searches were performed on the Test of Memory Malingering, the Victoria Symptom Validity Test, and the Word Memory Test. Results indicated that there is a variable amount of information available about each test that could threaten test security and validity should inappropriately interested parties find it. Steps that could be taken to improve this situation and limitations to this exploration are discussed.

  18. Atomistic study on shock behaviour of NiTi shape memory alloy

    Science.gov (United States)

    Yin, Qiuyun; Wu, Xianqian; Huang, Chenguang

    2017-06-01

    The shock behaviour of NiTi shape memory alloy is investigated by using molecular dynamics simulation. The nano-pillar samples of the alloy are subjected to the impact of a piston with a velocity of 350 m/s at initial environment temperatures of 325 and 500 K. At 325 K, we observe two different pathways of the formation of BCO phase, the gradient twins, and the detwinning phenomena, strongly depending on the local stress and the deformation state. As the initial temperature increases to 500 K, the plasticity is dominated by the dislocation movements rather than the twinning at 325 K. The phase transformation and plasticity result in stress attenuation when the stress wave propagates through the nano-pillar. Furthermore, it is interesting to note that multiple stress peaks occur due to the formation of local complex atomic structures with various wave speeds, leading to the catch up and overlap of the stress waves.

  19. Cue-induced alcohol-seeking behaviour is reduced by disrupting the reconsolidation of alcohol-related memories.

    Science.gov (United States)

    von der Goltz, Christoph; Vengeliene, Valentina; Bilbao, Ainhoa; Perreau-Lenz, Stephanie; Pawlak, Cornelius R; Kiefer, Falk; Spanagel, Rainer

    2009-08-01

    In humans, the retrieval of memories associated with an alcohol-related experience frequently evokes alcohol-seeking behaviour. The reconsolidation hypothesis states that a consolidated memory could again become labile and susceptible to disruption after memory retrieval. The aim of our study was to examine whether retrieval of alcohol-related memories undergoes a reconsolidation process. For this purpose, male Wistar rats were trained to self-administer ethanol in the presence of specific conditioned stimuli. Thereafter, animals were left undisturbed in their home cages for the following 21 days. Memory retrieval was performed in a single 5-min exposure to all alcohol-associated stimuli. The protein synthesis inhibitor anisomycin, the non-competitive N-methyl-D: -aspartate (NMDA) receptor antagonist MK-801 and acamprosate, a clinically used drug known to reduce a hyper-glutamatergic state, were given immediately after retrieval of alcohol-related memories. The impact of drug treatment on cue-induced alcohol-seeking behaviour was measured on the following day and 7 days later. Administration of both anisomycin and MK-801 reduced cue-induced alcohol-seeking behaviour, showing that memory reconsolidation was disrupted by these compounds. However, acamprosate had no effect on the reconsolidation process, suggesting that this process is not dependent on a hyper-glutamatergic state but is more related to protein synthesis and NMDA receptor activity. Pharmacological disruption of reconsolidation of alcohol-associated memories can be achieved by the use of NMDA antagonists and protein synthesis inhibitors and may thus provide a potential new therapeutic strategy for the prevention of relapse in alcohol addiction.

  20. Working memory, attentional regulation and the Star Counting Test.

    OpenAIRE

    Das-Smaal, E.A.; Jong, de, P.F.; Koopmans, J.R.

    1993-01-01

    The Star Counting Test (SCT) has been developed to measure the regulatory function of attention. In a previous study it was shown that the SCT is suited for assessment of this attentional aspect with children. The present study concerns a more difficult version aimed at young adults. In the literature, the regulatory function of attention is increasingly stressed and it has been linked to working memory functioning. In order to further determine the validity of the SCT, performance was checke...

  1. Superconductivity of the atomic nucleus and mechanism of memory and behaviour of the man

    International Nuclear Information System (INIS)

    Shermatov, E.N.; Nurmatov, L.A.

    2005-01-01

    Full text: The mechanism of memory is a key problem in understanding of behaviour of alive entities, including Man. It is considered, that the long term memory is bound to an associative bark. To the important properties of memory is the ability to retin a sequence of happening events and arbitrary to extract it. The population of information in memory determines behaviour of the Man depending on interior needs and exterior actions. The clearing up motivation moments in the behaviour of the Man is bound to a problem of origin of life and mechanism of memory. Origin of life and solution of the mechanism of memory connect to singularities of the line-ups of DNA and ferment protein. However intrinsic to alive plants of property does not imply immediately from physico-chemistry of each of these molecules. The line-ups of DNA and ferment protein cannot be channels of a long-term memory, thought they will execute the important role as a gear link of the information in a brain. Making of methods 'the image of alive brain': a positron emissive tomography, functional magnetic resonance both multichannel progress in understanding of the mechanism of memory. hey have allowed to construct the common plan of handling and transmission of information in motivation centers in a brain. According to existing representations process scheme of information processing in a brain is shown. This plan yields common representations about ring driving of excitation with its recovery to places of tentative projections after after-treatment in other structures of a brain. In outcome the significance of a signal and its ration to this or that need of organism is determined. Then the impulses of excitation came in motivation centers of an intermediate brain. Besides information synthesis, recovery of excitation on diffuse projections ensures also integration of separate indications of stimulus in a fashion. On an example of the man it is possible to note, that the brain of the nan has an

  2. An experimental test of state–behaviour feedbacks: gizzard mass and foraging behaviour in red knots

    NARCIS (Netherlands)

    Mathot, K.J.; Dekinga, A.; Piersma, T.

    2017-01-01

    1. Animals frequently exhibit consistent among-individual differences in behavioural and physiologicaltraits that are inherently flexible. Why should individuals differ consistently in theirexpression of labile traits? Recently, positive feedbacks between state and behaviour have beenproposed as a

  3. An experimental test of state–behaviour feedbacks : Gizzard mass and foraging behaviour in red knots

    NARCIS (Netherlands)

    Mathot, Kimberley J.; Dekinga, Anne; Piersma, Theunis

    2017-01-01

    Animals frequently exhibit consistent among-individual differences in behavioural and physiological traits that are inherently flexible. Why should individuals differ consistently in their expression of labile traits? Recently, positive feedbacks between state and behaviour have been proposed as a

  4. Behaviour of smart reinforced concrete beam with super elastic shape memory alloy subjected to monotonic loading

    Science.gov (United States)

    Hamid, Nubailah Abd; Ibrahim, Azmi; Adnan, Azlan; Ismail, Muhammad Hussain

    2018-05-01

    This paper discusses the superelastic behavior of shape memory alloy, NiTi when used as reinforcement in concrete beams. The ability of NiTi to recover and reduce permanent deformations of concrete beams was investigated. Small-scale concrete beams, with NiTi reinforcement were experimentally investigated under monotonic loads. The behaviour of simply supported reinforced concrete (RC) beams hybrid with NiTi rebars and the control beam subject to monotonic loads were experimentally investigated. This paper is to highlight the ability of the SMA bars to recover and reduce permanent deformations of concrete flexural members. The size of the control beam is 125 mm × 270 mm × 1000 mm with 3 numbers of 12 mm diameter bars as main reinforcement for compression and 3 numbers of 12 mm bars as tension or hanger bars while 6 mm diameter at 100 mm c/c used as shear reinforcement bars for control beam respectively. While, the minimal provision of 200mm using the 12.7mm of superelastic Shape Memory Alloys were employed to replace the steel rebar at the critical region of the beam. In conclusion, the contribution of the SMA bar in combination with high-strength steel to the conventional reinforcement showed that the SMA beam has exhibited an improve performance in term of better crack recovery and deformation. Therefore the usage of hybrid NiTi with the steel can substantially diminish the risk of the earthquake and also can reduce the associated cost aftermath.

  5. Test Reviews: Reynolds, C., & Voress, J. K. (2007). "Test of Memory and Learning: Second Edition." Austin, TX: PRO-ED

    Science.gov (United States)

    Schmitt, Ara J.; Decker, Scott L.

    2009-01-01

    This article reviews the Test of Memory and Learning: Second Edition (TOMAL-2), published by PRO-ED, which constitutes a recent revision of the Test of Memory and Learning (TOMAL; Reynolds & Bigler, 1994). Advertised as the "single most comprehensive memory battery available for the entire age range of 5 years through 59 years of age", the TOMAL-2…

  6. The Metamemory Approach to Confidence: A Test Using Semantic Memory

    Science.gov (United States)

    Brewer, William F.; Sampaio, Cristina

    2012-01-01

    The metamemory approach to memory confidence was extended and elaborated to deal with semantic memory tasks. The metamemory approach assumes that memory confidence is based on the products and processes of a completed memory task, as well as metamemory beliefs that individuals have about how their memory products and processes relate to memory…

  7. The Cambridge Car Memory Test: a task matched in format to the Cambridge Face Memory Test, with norms, reliability, sex differences, dissociations from face memory, and expertise effects.

    Science.gov (United States)

    Dennett, Hugh W; McKone, Elinor; Tavashmi, Raka; Hall, Ashleigh; Pidcock, Madeleine; Edwards, Mark; Duchaine, Bradley

    2012-06-01

    Many research questions require a within-class object recognition task matched for general cognitive requirements with a face recognition task. If the object task also has high internal reliability, it can improve accuracy and power in group analyses (e.g., mean inversion effects for faces vs. objects), individual-difference studies (e.g., correlations between certain perceptual abilities and face/object recognition), and case studies in neuropsychology (e.g., whether a prosopagnosic shows a face-specific or object-general deficit). Here, we present such a task. Our Cambridge Car Memory Test (CCMT) was matched in format to the established Cambridge Face Memory Test, requiring recognition of exemplars across view and lighting change. We tested 153 young adults (93 female). Results showed high reliability (Cronbach's alpha = .84) and a range of scores suitable both for normal-range individual-difference studies and, potentially, for diagnosis of impairment. The mean for males was much higher than the mean for females. We demonstrate independence between face memory and car memory (dissociation based on sex, plus a modest correlation between the two), including where participants have high relative expertise with cars. We also show that expertise with real car makes and models of the era used in the test significantly predicts CCMT performance. Surprisingly, however, regression analyses imply that there is an effect of sex per se on the CCMT that is not attributable to a stereotypical male advantage in car expertise.

  8. Frontal and temporal lobe contributions to emotional enhancement of memory in behavioural-variant frontotemporal dementia and Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Fiona eKumfor

    2014-06-01

    Full Text Available Emotional events gain special priority in how they are remembered, with emotionally arousing events typically recalled more vividly and with greater confidence than non-emotional events. In dementia, memory and emotion processing are affected to varying degrees, however, whether emotional enhancement of memory for complex ecologically valid events is differentially affected across dementia syndromes remains unclear, with previous studies examining effects of emotion on simple visual recognition only. Here, we examined memory for an emotionally arousing short story and a closely matched, emotionally neutral story in behavioural-variant frontotemporal dementia (bvFTD (n = 13 and Alzheimer’s disease (AD (n = 14, and contrasted their performance with healthy controls (n = 12. Multiple-choice recognition memory for specific details of the story was assessed after a 1-hour delay. While AD and control groups showed enhanced memory for the emotional story, the bvFTD group recalled a similar number of details from the emotional and neutral stories. Voxel-based morphometry analyses revealed emotional enhancement of memory correlated with distinct brain regions in each patient group. In AD, emotional enhancement was associated with integrity of the bilateral hippocampus, parahippocampal gyri, temporal fusiform gyrus and frontal pole, regions implicated in memory processes. In contrast in bvFTD, integrity of emotion processing regions, including the orbitofrontal cortex, right amygdala and right insula, correlated with the extent emotion enhanced memory. Our results reveal that integrity of frontal and temporal regions determine the quality and nature of emotional memories. While emotional enhancement of memory is present in mild AD, in bvFTD emotion does not facilitate memory retrieval for complex realistic events. This attenuation of emotional enhancement is due to degradation of emotion processing regions, which may be important for modulating levels

  9. MWCNTs-reinforced epoxidized linseed oil plasticized polylactic acid nanocomposite and its electroactive shape memory behaviour.

    Science.gov (United States)

    Alam, Javed; Alam, Manawwer; Raja, Mohan; Abduljaleel, Zainularifeen; Dass, Lawrence Arockiasamy

    2014-10-31

    A novel electroactive shape memory polymer nanocomposite of epoxidized linseed oil plasticized polylactic acid and multi-walled carbon nanotubes (MWCNTs) was prepared by a combination of solution blending, solvent cast technique, and hydraulic hot press moulding. In this study, polylactic acid (PLA) was first plasticized by epoxidized linseed oil (ELO) in order to overcome the major limitations of PLA, such as high brittleness, low toughness, and low tensile elongation. Then, MWCNTs were incorporated into the ELO plasticized PLA matrix at three different loadings (2, 3 and 5 wt. %), with the aim of making the resulting nanocomposites electrically conductive. The addition of ELO decreased glass transition temperature, and increased the elongation and thermal degradability of PLA, as shown in the results of differential scanning calorimetry (DSC), tensile test, and thermo gravimetric analysis (TGA). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to observe surface morphology, topography, and the dispersion of MWCNTs in the nanocomposite. Finally, the electroactive-shape memory effect (electroactive-SME) in the resulting nanocomposite was investigated by a fold-deploy "U"-shape bending test. As per the results, the addition of both ELO and MWCNTs to PLA matrix seemed to enhance its overall properties with a great deal of potential in improved shape memory. The 3 wt. % MWCNTs-reinforced nanocomposite system, which showed 95% shape recovery within 45 s at 40 DC voltage, is expected to be used as a preferential polymeric nanocomposite material in various actuators, sensors and deployable devices.

  10. MWCNTs-Reinforced Epoxidized Linseed Oil Plasticized Polylactic Acid Nanocomposite and Its Electroactive Shape Memory Behaviour

    Directory of Open Access Journals (Sweden)

    Javed Alam

    2014-10-01

    Full Text Available A novel electroactive shape memory polymer nanocomposite of epoxidized linseed oil plasticized polylactic acid and multi-walled carbon nanotubes (MWCNTs was prepared by a combination of solution blending, solvent cast technique, and hydraulic hot press moulding. In this study, polylactic acid (PLA was first plasticized by epoxidized linseed oil (ELO in order to overcome the major limitations of PLA, such as high brittleness, low toughness, and low tensile elongation. Then, MWCNTs were incorporated into the ELO plasticized PLA matrix at three different loadings (2, 3 and 5 wt. %, with the aim of making the resulting nanocomposites electrically conductive. The addition of ELO decreased glass transition temperature, and increased the elongation and thermal degradability of PLA, as shown in the results of differential scanning calorimetry (DSC, tensile test, and thermo gravimetric analysis (TGA. Scanning electron microscopy (SEM and atomic force microscopy (AFM were used to observe surface morphology, topography, and the dispersion of MWCNTs in the nanocomposite. Finally, the electroactive-shape memory effect (electroactive-SME in the resulting nanocomposite was investigated by a fold-deploy “U”-shape bending test. As per the results, the addition of both ELO and MWCNTs to PLA matrix seemed to enhance its overall properties with a great deal of potential in improved shape memory. The 3 wt. % MWCNTs-reinforced nanocomposite system, which showed 95% shape recovery within 45 s at 40 DC voltage, is expected to be used as a preferential polymeric nanocomposite material in various actuators, sensors and deployable devices.

  11. Wada test for evaluation of language and memory function in medically intractable epilepsy

    International Nuclear Information System (INIS)

    Hong, Yong Kook; Chung, Tae Sub; Suh, Jung Ho; Kim, Dong Ik; Kim, Eun Kyung; Lee, Byung In; Huh, Kyun

    1992-01-01

    The Wada test was performed for lateralization of language and memory function, using intracarotid injection of Sodium Amytal. But the internal carotid artery (ICA) Wada test has some limitations for testing memory function. The posterior cerebral artery (PCA) Wada test has been designed to modify the ICA Wada test for testing memory function selectively. In our study, 10 patients out of 12 patients with intractable seizure underwent only the ICA Wada test and the other 2 patients underwent both the ICA and the selective PCA Wada test. In all 12 patients undergoing the ICA Wada test, we successfully localized speech and language dominance. Four of 12 patients who underwent the ICA Wada test for evaluation of memory function displayed superior memory functions in one hemisphere, but the other hemisphere also significantly contributed to memory. The selective PCA Wada test, performed in 2 patients, showed successful results of memory function test in both patients. Four of 12 patients underwent temporal lobectomy and there was no major post-operative language or memory deficits. We concluded that the ICA and PCA Wada tests are useful for preoperative evaluation of medically intractable epilepsy, and the PCA Wada test is valuable in memory evaluation in some patients who have high risk of postoperative global amnesia after temporal lobectomy following equivocal results of memory function by the ICA Wada test

  12. Wada test for evaluation of language and memory function in medically intractable epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Yong Kook; Chung, Tae Sub; Suh, Jung Ho; Kim, Dong Ik; Kim, Eun Kyung; Lee, Byung In; Huh, Kyun [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

    1992-05-15

    The Wada test was performed for lateralization of language and memory function, using intracarotid injection of Sodium Amytal. But the internal carotid artery (ICA) Wada test has some limitations for testing memory function. The posterior cerebral artery (PCA) Wada test has been designed to modify the ICA Wada test for testing memory function selectively. In our study, 10 patients out of 12 patients with intractable seizure underwent only the ICA Wada test and the other 2 patients underwent both the ICA and the selective PCA Wada test. In all 12 patients undergoing the ICA Wada test, we successfully localized speech and language dominance. Four of 12 patients who underwent the ICA Wada test for evaluation of memory function displayed superior memory functions in one hemisphere, but the other hemisphere also significantly contributed to memory. The selective PCA Wada test, performed in 2 patients, showed successful results of memory function test in both patients. Four of 12 patients underwent temporal lobectomy and there was no major post-operative language or memory deficits. We concluded that the ICA and PCA Wada tests are useful for preoperative evaluation of medically intractable epilepsy, and the PCA Wada test is valuable in memory evaluation in some patients who have high risk of postoperative global amnesia after temporal lobectomy following equivocal results of memory function by the ICA Wada test.

  13. Individual Differences in Behavioural Despair Predict Brain GSK-3beta Expression in Mice: The Power of a Modified Swim Test.

    Science.gov (United States)

    Strekalova, Tatyana; Markova, Nataliia; Shevtsova, Elena; Zubareva, Olga; Bakhmet, Anastassia; Steinbusch, Harry M; Bachurin, Sergey; Lesch, Klaus-Peter

    2016-01-01

    While deficient brain plasticity is a well-established pathophysiologic feature of depression, little is known about disorder-associated enhanced cognitive processing. Here, we studied a novel mouse paradigm that potentially models augmented learning of adverse memories during development of a depressive-like state. We used a modification of the classic two-day protocol of a mouse Porsolt test with an additional session occurring on Day 5 following the initial exposure. Unexpectedly, floating behaviour and brain glycogen synthase kinase-3 beta (GSK-3beta) mRNA levels, a factor of synaptic plasticity as well as a marker of distress and depression, were increased during the additional swimming session that was prevented by imipramine. Observed increases of GSK-3beta mRNA in prefrontal cortex during delayed testing session correlated with individual parameters of behavioural despair that was not found in the classic Porsolt test. Repeated swim exposure was accompanied by a lower pGSK-3beta/GSK-3beta ratio. A replacement of the second or the final swim sessions with exposure to the context of testing resulted in increased GSK-3beta mRNA level similar to the effects of swimming, while exclusion of the second testing prevented these changes. Together, our findings implicate the activation of brain GSK-3beta expression in enhanced contextual conditioning of adverse memories, which is associated with an individual susceptibility to a depressive syndrome.

  14. Individual Differences in Behavioural Despair Predict Brain GSK-3beta Expression in Mice: The Power of a Modified Swim Test

    Directory of Open Access Journals (Sweden)

    Tatyana Strekalova

    2016-01-01

    Full Text Available While deficient brain plasticity is a well-established pathophysiologic feature of depression, little is known about disorder-associated enhanced cognitive processing. Here, we studied a novel mouse paradigm that potentially models augmented learning of adverse memories during development of a depressive-like state. We used a modification of the classic two-day protocol of a mouse Porsolt test with an additional session occurring on Day 5 following the initial exposure. Unexpectedly, floating behaviour and brain glycogen synthase kinase-3 beta (GSK-3beta mRNA levels, a factor of synaptic plasticity as well as a marker of distress and depression, were increased during the additional swimming session that was prevented by imipramine. Observed increases of GSK-3beta mRNA in prefrontal cortex during delayed testing session correlated with individual parameters of behavioural despair that was not found in the classic Porsolt test. Repeated swim exposure was accompanied by a lower pGSK-3beta/GSK-3beta ratio. A replacement of the second or the final swim sessions with exposure to the context of testing resulted in increased GSK-3beta mRNA level similar to the effects of swimming, while exclusion of the second testing prevented these changes. Together, our findings implicate the activation of brain GSK-3beta expression in enhanced contextual conditioning of adverse memories, which is associated with an individual susceptibility to a depressive syndrome.

  15. Controlled encoding strategies in memory tests in lithium patients.

    Science.gov (United States)

    Opgenoorth, E; Karlick-Bolten, E

    1986-03-01

    The "levels of processing" theory (Craik and Lockhart) and "dual coding" theory (Paivio) provide new aspects for clinical memory research work. Therefore, an incidental learning paradigm on the basis of these two theoretical approaches was chosen to test aspects of memory performances with lithium therapy. Results of two experiments, with controlled non-semantic processing (rating experiment "comparison of size") and additive semantic processing (rating "living--non-living") indicate a slight reduction in recall (Fig. 1) and recognition performance (Fig. 2) in lithium patients. Effects on encoding strategies are of equal quality in patients and healthy subjects (Tab. 1, 2) but performance differs between both groups: poorer systematic benefit from within code repetitions ("word-word" items, "picture-picture" items) and dual coding (repeated variable item presentation "picture-word") is obtained. The less efficient encoding strategies in the speeded task are discussed with respect to cognitive rigidity and slowing of performance by emotional states. This investigation of so-called "memory deficits" with lithium is an attempt to explore impairments at an early stage of processing; the characterization of the perceptual cognitive analysis seems useful for further clinical research work on this topic.

  16. A dual memory theory of the testing effect.

    Science.gov (United States)

    Rickard, Timothy C; Pan, Steven C

    2017-06-05

    A new theoretical framework for the testing effect-the finding that retrieval practice is usually more effective for learning than are other strategies-is proposed, the empirically supported tenet of which is that separate memories form as a consequence of study and test events. A simplest case quantitative model is derived from that framework for the case of cued recall. With no free parameters, that model predicts both proportion correct in the test condition and the magnitude of the testing effect across 10 experiments conducted in our laboratory, experiments that varied with respect to material type, retention interval, and performance in the restudy condition. The model also provides the first quantitative accounts of (a) the testing effect as a function of performance in the restudy condition, (b) the upper bound magnitude of the testing effect, (c) the effect of correct answer feedback, (d) the testing effect as a function of retention interval for the cases of feedback and no feedback, and (e) the effect of prior learning method on subsequent learning through testing. Candidate accounts of several other core phenomena in the literature, including test-potentiated learning, recognition versus cued recall training effects, cued versus free recall final test effects, and other select transfer effects, are also proposed. Future prospects and relations to other theories are discussed.

  17. Assessment of Nondeclarative Learning in Severe Alzheimer Dementia The Implicit Memory Test (IMT)

    NARCIS (Netherlands)

    Kessels, R.P.C.; Remmerswaal, M.; Wilson, B.A.

    2011-01-01

    Although patients with Alzheimer dementia (AD) have impaired explicit memory, more automatic, implicit aspects of learning and memory may be relatively preserved. However, neuropsychological tests for the assessment of implicit memory are lacking. This study examines a newly developed test, the

  18. Assessment of nondeclarative learning in severe Alzheimer dementia: the Implicit Memory Test (IMT)

    NARCIS (Netherlands)

    Kessels, R.P.C.; Remmerswaal, M.; Wilson, B.A.

    2011-01-01

    Although patients with Alzheimer dementia (AD) have impaired explicit memory, more automatic, implicit aspects of learning and memory may be relatively preserved. However, neuropsychological tests for the assessment of implicit memory are lacking. This study examines a newly developed test, the

  19. Biomechanical behaviour - Anisotropy of eye cornea through experimental strip tests

    Science.gov (United States)

    Arsalan Khan, Mohammad; Elsheikh, Ahmed; Khan, Iqtedar Ahmad

    2018-02-01

    With the advent of research it was identified that material properties are responsible for errors in tonometry pressure (referred to as Goldmann IOP or IOPG) with the stiffening of a composite structure of corneal tissue in particular. Strip tensile tests are conducted to determine their stress-strain relationship for the purpose to study the behaviour of material properties of cornea. Specimens are taken from the superior-inferior (vertical) and temporal- nasal (horizontal) directions. Testing is performed on an Instron machine, under different rate of loading conditions. First set of experiment, with single strain rate, is executed on eyes having random population. While the second set of experiment is executed on eyes of the same animal in both directions, and different strain rates are applied each specimen. Relatively, the first set of experiment is found to be slightly different and less accurate. In general, it is found that the vertical specimen is 34% on an average stiffer than the horizontal specimen compared to Kampmeier et al. of 20% (studied in 2000) and Defu Wang of 15% (studied in 2007). Curve fitting coefficients are also evaluated for 4-degree polynomial. The anisotropy is evident by plotting the ratio of E-tangent value of vertical Ev and horizontal Eh against stresses with individual strain rates. The value of Ev/Eh increases with slightly slow rate with stresses as compared to achieved through slow strain rates.

  20. Behaviour of Ti-doped CFCs under thermal fatigue tests

    Energy Technology Data Exchange (ETDEWEB)

    Centeno, A. [Instituto Nacional del Carbon (CSIC), Apdo. 73, 33080 Oviedo (Spain); Pintsuk, G.; Linke, J. [Forschungszentrum Juelich GmbH, EURATOM Association, 52425 Juelich (Germany); Gualco, C. [Ansaldo Energia, I-16152 Genoa (Italy); Blanco, C., E-mail: clara@incar.csic.es [Instituto Nacional del Carbon (CSIC), Apdo. 73, 33080 Oviedo (Spain); Santamaria, R.; Granda, M.; Menendez, R. [Instituto Nacional del Carbon (CSIC), Apdo. 73, 33080 Oviedo (Spain)

    2011-01-15

    In spite of the remarkable progress in the design of in-vessel components for the divertor of the first International Thermonuclear Experimental Reactor (ITER), a great effort is still put into the development of manufacturing technologies for carbon armour with improved properties. Newly developed 3D titanium-doped carbon fibre reinforced composites and their corresponding undoped counterparts were brazed to a CuCrZr heat sink to produce actively cooled flat tile mock-ups. By exposing the mock-ups to thermal fatigue tests in an electron beam test facility, the material behaviour and the brazing between the individual constituents in the mock-up was qualified. The mock-ups with titanium-doped CFCs exhibited a significantly improved thermal fatigue resistance compared with those undoped materials. The comparison of these mock-ups with those produced using pristine NB31, one of the reference materials as plasma facing material for ITER, showed almost identical results, indicating the high potential of Ti-doped CFCs due to their improved thermal shock resistance.

  1. Orexin signaling during social defeat stress influences subsequent social interaction behaviour and recognition memory.

    Science.gov (United States)

    Eacret, Darrell; Grafe, Laura A; Dobkin, Jane; Gotter, Anthony L; Rengerb, John J; Winrow, Christopher J; Bhatnagar, Seema

    2018-06-11

    Orexins are neuropeptides synthesized in the lateral hypothalamus that influence arousal, feeding, reward pathways, and the response to stress. However, the role of orexins in repeated stress is not fully characterized. Here, we examined how orexins and their receptors contribute to the coping response during repeated social defeat and subsequent anxiety-like and memory-related behaviors. Specifically, we used Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) to stimulate orexins prior to each of five consecutive days of social defeat stress in adult male rats. Additionally, we determined the role of the orexin 2 receptor in these behaviors by using a selective orexin 2 receptor antagonist (MK-1064) administered prior to each social defeat. Following the 5 day social defeat conditioning period, rats were evaluated in social interaction and novel object recognition paradigms to assess anxiety-like behavior and recognition memory, respectively. Activation of orexin neurons by DREADDs prior to each social defeat decreased the average latency to become defeated across 5 days, indicative of a passive coping strategy that we have previously linked to a stress vulnerable phenotype. Moreover, stimulation of orexin signaling during defeat conditioning decreased subsequent social interaction and performance in the novel object recognition test indicating increased subsequent anxiety-like behavior and reduced working memory. Blocking the orexin 2 receptor during repeated defeat did not alter these effects. Together, our results suggest that orexin neuron activation produces a passive coping phenotype during social defeat leading to subsequent anxiety-like behaviors and memory deficits. Copyright © 2018. Published by Elsevier B.V.

  2. Not All Order Memory Is Equal: Test Demands Reveal Dissociations in Memory for Sequence Information

    Science.gov (United States)

    Jonker, Tanya R.; MacLeod, Colin M.

    2017-01-01

    Remembering the order of a sequence of events is a fundamental feature of episodic memory. Indeed, a number of formal models represent temporal context as part of the memory system, and memory for order has been researched extensively. Yet, the nature of the code(s) underlying sequence memory is still relatively unknown. Across 4 experiments that…

  3. Correlation between two parameters of mice behaviour in the open field test

    OpenAIRE

    Stojanović, Nikola M.; Ranđelović, Pavle J.; Radulović, Niko S.

    2017-01-01

    The open field test is being used extensively for the determination of different aspects of animal behaviour for over seventy years. The correlation between different behavioural parameters obtained in this test, although previously studied, is still debatable. Thus, we aimed to analyze and correlate behaviour scores to estimate the importance of individual parameters in this type of experiment. The open field test was performed on male BALB/c mice treated with either saline (10 ml/kg) or dia...

  4. Memory Binding Test Predicts Incident Amnestic Mild Cognitive Impairment.

    Science.gov (United States)

    Mowrey, Wenzhu B; Lipton, Richard B; Katz, Mindy J; Ramratan, Wendy S; Loewenstein, David A; Zimmerman, Molly E; Buschke, Herman

    2016-07-14

    The Memory Binding Test (MBT), previously known as Memory Capacity Test, has demonstrated discriminative validity for distinguishing persons with amnestic mild cognitive impairment (aMCI) and dementia from cognitively normal elderly. We aimed to assess the predictive validity of the MBT for incident aMCI. In a longitudinal, community-based study of adults aged 70+, we administered the MBT to 246 cognitively normal elderly adults at baseline and followed them annually. Based on previous work, a subtle reduction in memory binding at baseline was defined by a Total Items in the Paired (TIP) condition score of ≤22 on the MBT. Cox proportional hazards models were used to assess the predictive validity of the MBT for incident aMCI accounting for the effects of covariates. The hazard ratio of incident aMCI was also assessed for different prediction time windows ranging from 4 to 7 years of follow-up, separately. Among 246 controls who were cognitively normal at baseline, 48 developed incident aMCI during follow-up. A baseline MBT reduction was associated with an increased risk for developing incident aMCI (hazard ratio (HR) = 2.44, 95% confidence interval: 1.30-4.56, p = 0.005). When varying the prediction window from 4-7 years, the MBT reduction remained significant for predicting incident aMCI (HR range: 2.33-3.12, p: 0.0007-0.04). Persons with poor performance on the MBT are at significantly greater risk for developing incident aMCI. High hazard ratios up to seven years of follow-up suggest that the MBT is sensitive to early disease.

  5. Fault Localization Method by Partitioning Memory Using Memory Map and the Stack for Automotive ECU Software Testing

    Directory of Open Access Journals (Sweden)

    Kwanhyo Kim

    2016-09-01

    Full Text Available Recently, the usage of the automotive Electronic Control Unit (ECU and its software in cars is increasing. Therefore, as the functional complexity of such software increases, so does the likelihood of software-related faults. Therefore, it is important to ensure the reliability of ECU software in order to ensure automobile safety. For this reason, systematic testing methods are required that can guarantee software quality. However, it is difficult to locate a fault during testing with the current ECU development system because a tester performs the black-box testing using a Hardware-in-the-Loop (HiL simulator. Consequently, developers consume a large amount of money and time for debugging because they perform debugging without any information about the location of the fault. In this paper, we propose a method for localizing the fault utilizing memory information during black-box testing. This is likely to be of use to developers who debug automotive software. In order to observe whether symbols stored in the memory have been updated, the memory is partitioned by a memory map and the stack, thus the fault candidate region is reduced. A memory map method has the advantage of being able to finely partition the memory, and the stack method can partition the memory without a memory map. We validated these methods by applying these to HiL testing of the ECU for a body control system. The preliminary results indicate that a memory map and the stack reduce the possible fault locations to 22% and 19% of the updated memory, respectively.

  6. Memory functions in chronic pain: examining contributions of attention and age to test performance.

    Science.gov (United States)

    Oosterman, Joukje M; Derksen, Laura C; van Wijck, Albert J M; Veldhuijzen, Dieuwke S; Kessels, Roy P C

    2011-01-01

    Previous studies have revealed that memory performance is diminished in chronic pain patients. Few studies, however, have assessed multiple components of memory in a single sample. It is currently also unknown whether attentional problems, which are commonly observed in chronic pain, mediate the decline in memory. Finally, previous studies have focused on middle-aged adults, and a possible detrimental effect of aging on memory performance in chronic pain patients has been commonly disregarded. This study, therefore, aimed at describing the pattern of semantic, working, and visual and verbal episodic memory performance in participants with chronic pain, while testing for possible contributions of attention and age to task performance. Thirty-four participants with chronic pain and 32 pain-free participants completed tests of episodic, semantic, and working memory to assess memory performance and a test of attention. Participants with chronic pain performed worse on tests of working memory and verbal episodic memory. A decline in attention explained some, but not all, group differences in memory performance. Finally, no additional effect of age on the diminished task performance in participants with chronic pain was observed. Taken together, the results indicate that chronic pain significantly affects memory performance. Part of this effect may be caused by underlying attentional dysfunction, although this could not fully explain the observed memory decline. An increase in age in combination with the presence of chronic pain did not additionally affect memory performance.

  7. A Systematic Review of the Reliability and Validity of Behavioural Tests Used to Assess Behavioural Characteristics Important in Working Dogs.

    Science.gov (United States)

    Brady, Karen; Cracknell, Nina; Zulch, Helen; Mills, Daniel Simon

    2018-01-01

    Working dogs are selected based on predictions from tests that they will be able to perform specific tasks in often challenging environments. However, withdrawal from service in working dogs is still a big problem, bringing into question the reliability of the selection tests used to make these predictions. A systematic review was undertaken aimed at bringing together available information on the reliability and predictive validity of the assessment of behavioural characteristics used with working dogs to establish the quality of selection tests currently available for use to predict success in working dogs. The search procedures resulted in 16 papers meeting the criteria for inclusion. A large range of behaviour tests and parameters were used in the identified papers, and so behaviour tests and their underpinning constructs were grouped on the basis of their relationship with positive core affect (willingness to work, human-directed social behaviour, object-directed play tendencies) and negative core affect (human-directed aggression, approach withdrawal tendencies, sensitivity to aversives). We then examined the papers for reports of inter-rater reliability, within-session intra-rater reliability, test-retest validity and predictive validity. The review revealed a widespread lack of information relating to the reliability and validity of measures to assess behaviour and inconsistencies in terminologies, study parameters and indices of success. There is a need to standardise the reporting of these aspects of behavioural tests in order to improve the knowledge base of what characteristics are predictive of optimal performance in working dog roles, improving selection processes and reducing working dog redundancy. We suggest the use of a framework based on explaining the direct or indirect relationship of the test with core affect.

  8. Symptom validity testing in memory clinics: Hippocampal-memory associations and relevance for diagnosing mild cognitive impairment.

    Science.gov (United States)

    Rienstra, Anne; Groot, Paul F C; Spaan, Pauline E J; Majoie, Charles B L M; Nederveen, Aart J; Walstra, Gerard J M; de Jonghe, Jos F M; van Gool, Willem A; Olabarriaga, Silvia D; Korkhov, Vladimir V; Schmand, Ben

    2013-01-01

    Patients with mild cognitive impairment (MCI) do not always convert to dementia. In such cases, abnormal neuropsychological test results may not validly reflect cognitive symptoms due to brain disease, and the usual brain-behavior relationships may be absent. This study examined symptom validity in a memory clinic sample and its effect on the associations between hippocampal volume and memory performance. Eleven of 170 consecutive patients (6.5%; 13% of patients younger than 65 years) referred to memory clinics showed noncredible performance on symptom validity tests (SVTs, viz. Word Memory Test and Test of Memory Malingering). They were compared to a demographically matched group (n = 57) selected from the remaining patients. Hippocampal volume, measured by an automated volumetric method (Freesurfer), was correlated with scores on six verbal memory tests. The median correlation was r = .49 in the matched group. However, the relation was absent (median r = -.11) in patients who failed SVTs. Memory clinic samples may include patients who show noncredible performance, which invalidates their MCI diagnosis. This underscores the importance of applying SVTs in evaluating patients with cognitive complaints that may signify a predementia stage, especially when these patients are relatively young.

  9. In search of memory tests equivalent for experiments on animals and humans.

    Science.gov (United States)

    Brodziak, Andrzej; Kołat, Estera; Różyk-Myrta, Alicja

    2014-12-19

    Older people often exhibit memory impairments. Contemporary demographic trends cause aging of the society. In this situation, it is important to conduct clinical trials of drugs and use training methods to improve memory capacity. Development of new memory tests requires experiments on animals and then clinical trials in humans. Therefore, we decided to review the assessment methods and search for tests that evaluate analogous cognitive processes in animals and humans. This review has enabled us to propose 2 pairs of tests of the efficiency of working memory capacity in animals and humans. We propose a basic set of methods for complex clinical trials of drugs and training methods to improve memory, consisting of 2 pairs of tests: 1) the Novel Object Recognition Test - Sternberg Item Recognition Test and 2) the Object-Location Test - Visuospatial Memory Test. We postulate that further investigations of methods that are equivalent in animals experiments and observations performed on humans are necessary.

  10. Effects of transient global ischaemia on freezing behaviour and activity in a context-dependent fear conditioning task--implications for memory investigations.

    Science.gov (United States)

    Henrich-Noack, Petra; Krautwald, Karla; Reymann, Klaus G; Wetzel, Wolfram

    2011-07-15

    Transient global ischaemia induces cell death in the CA1 layer of the hippocampus. To evaluate the functional consequences, we performed context-dependent fear conditioning. Ischaemia was induced by 2-vessel-occlusion (2VO) in gerbils. On day 6 post ischaemia or sham procedures (in control group) gerbils were placed in a test chamber and after 3 min adaption time exposed to foot-shocks (training session). On the next day the animals were placed in the same test chamber without foot-shocks (test session). As a parameter for memory performance we used the standard method of measuring the total freezing time via a cumulative time-sampling procedure during the test session. We found a significant longer total freezing time in control animals than in ischaemic animals. In addition, however, we applied a more detailed analysis of (i) quantifying the number of freezing bouts, (ii) the average duration of single freezing bouts, (iii) the activity pattern during the training and test situation and (iv) we differentially evaluated all the single time segments of the experiment. These analyses revealed that although maintenance of freezing (duration of freezing bout) was significantly lower in ischaemic animals compared to controls, the initiation of freezing (number of freezing bouts) was not significantly different between the two groups during the test session. The activity scores of ischaemic and non-ischaemic gerbils were similar during the adaption time of the training session. The foot-shock, however, induced a significantly different pattern of behaviour in the ischaemic animals, which was selectively reproduced during the test session. In conclusion, ischaemic gerbils reacted to a fearsome thread with a behavioural pattern different from unlesioned animals and they revealed this specific foot-shock induced behaviour again during the test session. This indicated that CA1 hippocampal death did not interrupt memory performance but changed expression of fear. Therefore

  11. Heads for learning, tails for memory: Reward, reinforcement and a role of dopamine in determining behavioural relevance across multiple timescales

    Directory of Open Access Journals (Sweden)

    Mathieu eBaudonnat

    2013-10-01

    Full Text Available Dopamine has long been tightly associated with aspects of reinforcement learning and motivation in simple situations where there are a limited number of stimuli to guide behaviour and constrained range of outcomes. In naturalistic situations, however, there are many potential cues and foraging strategies that could be adopted, and it is critical that animals determine what might be behaviourally relevant in such complex environments. This requires not only detecting discrepancies with what they have recently experienced, but also identifying similarities with past experiences stored in memory. Here, we review what role dopamine might play in determining how and when to learn about the world, and how to develop choice policies appropriate to the situation faced. We discuss evidence that dopamine is shaped by motivation and memory and in turn shapes reward-based memory formation. In particular, we suggest that hippocampal-striatal-dopamine networks may interact to determine how surprising the world is and to either inhibit or promote actions at time of behavioural uncertainty.

  12. Suppressing Unwanted Autobiographical Memories Reduces Their Automatic Influences: Evidence From Electrophysiology and an Implicit Autobiographical Memory Test.

    Science.gov (United States)

    Hu, Xiaoqing; Bergström, Zara M; Bodenhausen, Galen V; Rosenfeld, J Peter

    2015-07-01

    The present study investigated the extent to which people can suppress unwanted autobiographical memories in a memory-detection context involving a mock crime. Participants encoded sensorimotor-rich memories by enacting a lab-based crime (stealing a ring) and received instructions to suppress memory of the crime in order to evade guilt detection in a brain-wave-based concealed-information test. Aftereffects of suppression on automatic memory processes were measured in an autobiographical Implicit Association Test. Results showed that suppression attenuated brain-wave activity (the P300) associated with crime-relevant memory retrieval, which rendered waveforms from innocent and guilty participants indistinguishable. However, the two groups could nevertheless be discriminated via the late-posterior-negative slow wave, which may reflect the need to monitor response conflict arising between voluntary suppression and automatic recognition processes. Finally, extending recent findings that suppression can impair implicit memory processes, we provide novel evidence that suppression reduces automatic cognitive biases often associated with actual autobiographical memories. © The Author(s) 2015.

  13. Implementation of a finite element analysis procedure for structural analysis of shape memory behaviour of fibre reinforced shape memory polymer composites

    Science.gov (United States)

    Azzawi, Wessam Al; Epaarachchi, J. A.; Islam, Mainul; Leng, Jinsong

    2017-12-01

    Shape memory polymers (SMPs) offer a unique ability to undergo a substantial shape deformation and subsequently recover the original shape when exposed to a particular external stimulus. Comparatively low mechanical properties being the major drawback for extended use of SMPs in engineering applications. However the inclusion of reinforcing fibres in to SMPs improves mechanical properties significantly while retaining intrinsic shape memory effects. The implementation of shape memory polymer composites (SMPCs) in any engineering application is a unique task which requires profound materials and design optimization. However currently available analytical tools have critical limitations to undertake accurate analysis/simulations of SMPC structures and slower derestrict transformation of breakthrough research outcomes to real-life applications. Many finite element (FE) models have been presented. But majority of them require a complicated user-subroutines to integrate with standard FE software packages. Furthermore, those subroutines are problem specific and difficult to use for a wider range of SMPC materials and related structures. This paper presents a FE simulation technique to model the thermomechanical behaviour of the SMPCs using commercial FE software ABAQUS. Proposed technique incorporates material time-dependent viscoelastic behaviour. The ability of the proposed technique to predict the shape fixity and shape recovery was evaluated by experimental data acquired by a bending of a SMPC cantilever beam. The excellent correlation between the experimental and FE simulation results has confirmed the robustness of the proposed technique.

  14. Tests of a Structural Theory of the Memory Trace.

    Science.gov (United States)

    Jones, Gregory V.

    1978-01-01

    Jones (1976) has shown that the memory trace resulting from the viewing of a picture corresponds to a "fragment" of that picture. This research shows that the fragmentation hypothesis also correctly represents the recall of memories derived from sentences, i.e., the functional unit of memory, the mnemonic trace, is a fragment of the original item.…

  15. Effects of laboratory housing on exploratory behaviour, novelty discrimination and spatial reference memory in a subterranean, solitary rodent, the Cape mole-rat (Georychus capensis).

    Science.gov (United States)

    Oosthuizen, Maria Kathleen; Scheibler, Anne-Gita; Bennett, Nigel Charles; Amrein, Irmgard

    2013-01-01

    A large number of laboratory and field based studies are being carried out on mole-rats, both in our research group and others. Several studies have highlighted the development of adverse behaviours in laboratory animals and have emphasised the importance of enrichment for captive animals. Hence we were interested in evaluating how laboratory housing would affect behavioural performance in mole-rats. We investigated exploratory behaviour, the ability to discriminate between novel and familiar environments and reference memory in the solitary Cape mole-rat (Georychus capensis). Our data showed that both wild and captive animals readily explore open spaces and tunnels. Wild animals were however more active than their captive counterparts. In the Y maze two trial discrimination task, wild animals failed to discriminate between novel and familiar environments, while laboratory housed mole-rats showed preferential spatial discrimination in terms of the length of time spent in the novel arm. The performance of the laboratory and wild animals were similar when tested for reference memory in the Y maze, both groups showed a significant improvement compared to the first day, from the 3rd day onwards. Wild animals made more mistakes whereas laboratory animals were slower in completing the task. The difference in performance between wild and laboratory animals in the Y-maze may be as a result of the lower activity of the laboratory animals. Laboratory maintained Cape mole-rats show classic behaviours resulting from a lack of stimulation such as reduced activity and increased aggression. However, they do display an improved novelty discrimination compared to the wild animals. Slower locomotion rate of the laboratory animals may increase the integration time of stimuli, hence result in a more thorough inspection of the surroundings. Unlike the captive animals, wild animals show flexibility in their responses to unpredictable events, which is an important requirement under

  16. In vitro corrosion behaviour of Ti-Nb-Sn shape memory alloys in Ringer's physiological solution.

    Science.gov (United States)

    Rosalbino, F; Macciò, D; Scavino, G; Saccone, A

    2012-04-01

    The nearly equiatomic Ni-Ti alloy (Nitinol) has been widely employed in the medical and dental fields owing to its shape memory or superelastic properties. The main concern about the use of this alloy derives form the fact that it contains a large amount of nickel (55% by mass), which is suspected responsible for allergic, toxic and carcinogenic reactions. In this work, the in vitro corrosion behavior of two Ti-Nb-Sn shape memory alloys, Ti-16Nb-5Sn and Ti-18Nb-4Sn (mass%) has been investigated and compared with that of Nitinol. The in vitro corrosion resistance was assessed in naturally aerated Ringer's physiological solution at 37°C by corrosion potential and electrochemical impedance spectroscopy (EIS) measurements as a function of exposure time, and potentiodynamic polarization curves. Corrosion potential values indicated that both Ni-Ti and Ti-Nb-Sn alloys undergo spontaneous passivation due to spontaneously formed oxide film passivating the metallic surface, in the aggressive environment. It also indicated that the tendency for the formation of a spontaneous oxide is greater for the Ti-18Nb-5Sn alloy. Significantly low anodic current density values were obtained from the polarization curves, indicating a typical passive behaviour for all investigated alloys, but Nitinol exhibited breakdown of passivity at potentials above approximately 450 mV(SCE), suggesting lower corrosion protection characteristics of its oxide film compared to the Ti-Nb-Sn alloys. EIS studies showed high impedance values for all samples, increasing with exposure time, indicating an improvement in corrosion resistance of the spontaneous oxide film. The obtained EIS spectra were analyzed using an equivalent electrical circuit representing a duplex structure oxide film, composed by an outer and porous layer (low resistance), and an inner barrier layer (high resistance) mainly responsible for the alloys corrosion resistance. The resistance of passive film present on the metals' surface

  17. Schizophrenia patients demonstrate a dissociation on declarative and non-declarative memory tests.

    Science.gov (United States)

    Perry, W; Light, G A; Davis, H; Braff, D L

    2000-12-15

    Declarative memory refers to the recall and recognition of factual information. In contrast, non-declarative memory entails a facilitation of memory based on prior exposure and is typically assessed with priming and perceptual-motor sequencing tasks. In this study, schizophrenia patients were compared to normal comparison subjects on two computerized memory tasks: the Word-stem Priming Test (n=30) and the Pattern Sequence Learning Test (n=20). Word-stem Priming includes recall, recognition (declarative) and priming (non-declarative) components of memory. The schizophrenia patients demonstrated an impaired performance on recall of words with relative improvement during the recognition portion of the test. Furthermore, they performed normally on the priming portion of the test. Thus, on tests of declarative memory, the patients had retrieval deficits with intact performance on the non-declarative memory component. The Pattern Sequence Learning Test utilizes a serial reaction time paradigm to assess non-declarative memory. The schizophrenia patients' serial reaction time was significantly slower than that of comparison subjects. However, the patients' rate of acquisition was not different from the normal comparison group. The data suggest that patients with schizophrenia process more slowly than normal, but have an intact non-declarative memory. The schizophrenia patients' dissociation on declarative vs. non-declarative memory tests is discussed in terms of possible underlying structural impairment.

  18. Specificity in autobiographical memory narratives correlates with performance on the Autobiographical Memory Test and prospectively predicts depressive symptoms

    Science.gov (United States)

    Sumner, Jennifer A.; Mineka, Susan; McAdams, Dan P.

    2012-01-01

    Reduced autobiographical memory specificity (AMS) is an important cognitive marker in depression that is typically measured with the Autobiographical Memory Test (AMT; Williams & Broadbent, 1986). The AMT is widely used, but the overreliance on a single methodology for assessing AMS is a limitation in the field. The current study investigated memory narratives as an alternative measure of AMS in an undergraduate student sample selected for being high or low on a measure of depressive symptoms (N = 55). We employed a multi-method design to compare narrative- and AMT-based measures of AMS. Participants generated personally significant self-defining memory narratives, and also completed two versions of the AMT (with and without instructions to retrieve specific memories). Greater AMS in self-defining memory narratives correlated with greater AMS in performance on both versions of the AMT in the full sample, and the patterns of relationships between the different AMS measures were generally similar in low and high dysphoric participants. Furthermore, AMS in self-defining memory narratives was prospectively associated with depressive symptom levels. Specifically, greater AMS in self-defining memory narratives predicted fewer depressive symptoms at a 10-week follow-up over and above baseline symptom levels. Implications for future research and clinical applications are discussed. PMID:23240988

  19. Memory

    Science.gov (United States)

    ... it has to decide what is worth remembering. Memory is the process of storing and then remembering this information. There are different types of memory. Short-term memory stores information for a few ...

  20. A behavioural investigation of human visual short term memory for colour.

    Science.gov (United States)

    Nemes, V A; Parry, N R A; McKeefry, D J

    2010-09-01

    We examined visual short term memory (VSTM) for colour using a delayed-match-to-sample paradigm. In these experiments we measured the effects of increasing inter-stimulus interval (ISI), varying between 0 and 10 s, on the ability of five colour normal human observers to make colour matches between a reference and subsequently presented test stimuli. The coloured stimuli used were defined by different chromatic axes on the isoluminant plane of DKL colour space. In preliminary experiments we used a hue scaling procedure to identify a total of 12 colour stimuli which served as reference hues in the colour memory experiments: four stimuli were exemplars of red, green, blue and yellow colour appearance categories, four were located between these categories and a further four were located on the cardinal axes that isolated the activity of the cone-opponent mechanisms. Our results demonstrate that there is a reduction in the ability of observers to make accurate colour matches with increasing ISIs and that this reduced performance was similar for all colour stimuli. However, the shifts in hue that were measured between the reference and matched test stimuli were significantly greater for the cardinal stimuli compared to those measured for the stimuli defined by the hue scaling procedure. This deterioration in the retention of hue in VSTM for stimuli that isolate cone-opponent mechanisms may be a reflection of the reorganisation of colour processing that occurs in the cortex where colour appearance mechanisms become more prominent. © 2010 The Authors, Ophthalmic and Physiological Optics © 2010 The College of Optometrists.

  1. Programs for Testing Processor-in-Memory Computing Systems

    Science.gov (United States)

    Katz, Daniel S.

    2006-01-01

    The Multithreaded Microbenchmarks for Processor-In-Memory (PIM) Compilers, Simulators, and Hardware are computer programs arranged in a series for use in testing the performances of PIM computing systems, including compilers, simulators, and hardware. The programs at the beginning of the series test basic functionality; the programs at subsequent positions in the series test increasingly complex functionality. The programs are intended to be used while designing a PIM system, and can be used to verify that compilers, simulators, and hardware work correctly. The programs can also be used to enable designers of these system components to examine tradeoffs in implementation. Finally, these programs can be run on non-PIM hardware (either single-threaded or multithreaded) using the POSIX pthreads standard to verify that the benchmarks themselves operate correctly. [POSIX (Portable Operating System Interface for UNIX) is a set of standards that define how programs and operating systems interact with each other. pthreads is a library of pre-emptive thread routines that comply with one of the POSIX standards.

  2. Initial Results from On-Orbit Testing of the Fram Memory Test Experiment on the Fastsat Micro-Satellite

    Science.gov (United States)

    MacLeond, Todd C.; Sims, W. Herb; Varnavas,Kosta A.; Ho, Fat D.

    2011-01-01

    The Memory Test Experiment is a space test of a ferroelectric memory device on a low Earth orbit satellite that launched in November 2010. The memory device being tested is a commercial Ramtron Inc. 512K memory device. The circuit was designed into the satellite avionics and is not used to control the satellite. The test consists of writing and reading data with the ferroelectric based memory device. Any errors are detected and are stored on board the satellite. The data is sent to the ground through telemetry once a day. Analysis of the data can determine the kind of error that was found and will lead to a better understanding of the effects of space radiation on memory systems. The test is one of the first flight demonstrations of ferroelectric memory in a near polar orbit which allows testing in a varied radiation environment. The initial data from the test is presented. This paper details the goals and purpose of this experiment as well as the development process. The process for analyzing the data to gain the maximum understanding of the performance of the ferroelectric memory device is detailed.

  3. Development of Next Generation Memory Test Experiment for Deployment on a Small Satellite

    Science.gov (United States)

    MacLeod, Todd; Ho, Fat D.

    2012-01-01

    The original Memory Test Experiment successfully flew on the FASTSAT satellite launched in November 2010. It contained a single Ramtron 512K ferroelectric memory. The memory device went through many thousands of read/write cycles and recorded any errors that were encountered. The original mission length was schedule to last 6 months but was extended to 18 months. New opportunities exist to launch a similar satellite and considerations for a new memory test experiment should be examined. The original experiment had to be designed and integrated in less than two months, so the experiment was a simple design using readily available parts. The follow-on experiment needs to be more sophisticated and encompass more technologies. This paper lays out the considerations for the design and development of this follow-on flight memory experiment. It also details the results from the original Memory Test Experiment that flew on board FASTSAT. Some of the design considerations for the new experiment include the number and type of memory devices to be used, the kinds of tests that will be performed, other data needed to analyze the results, and best use of limited resources on a small satellite. The memory technologies that are considered are FRAM, FLASH, SONOS, Resistive Memory, Phase Change Memory, Nano-wire Memory, Magneto-resistive Memory, Standard DRAM, and Standard SRAM. The kinds of tests that could be performed are read/write operations, non-volatile memory retention, write cycle endurance, power measurements, and testing Error Detection and Correction schemes. Other data that may help analyze the results are GPS location of recorded errors, time stamp of all data recorded, radiation measurements, temperature, and other activities being perform by the satellite. The resources of power, volume, mass, temperature, processing power, and telemetry bandwidth are extremely limited on a small satellite. Design considerations must be made to allow the experiment to not interfere

  4. Summary report - development of laboratory tests and the stress- strain behaviour of Olkiluoto mica gneiss

    Energy Technology Data Exchange (ETDEWEB)

    Hakala, M.; Heikkilae, E. [Helsinki Univ. of Technology, Espoo (Finland). Lab. of Rock Engineering

    1997-05-01

    This work summarizes the project aimed at developing and qualifying a suitable combination of laboratory tests to establish a statistically reliable stress-strain behaviour of the main rock types at Posiva Oy`s detailed investigation sites for disposal of spent nuclear fuel. The work includes literature study of stress-strain behaviour of brittle rock, development and qualification of laboratory tests, suggested test procedures and interpretation methods and finally testing of Olkiluoto mica gneiss. The Olkiluoto study includes over 130 loading tests. Besides the commonly used laboratory tests, direct tensile tests, damage controlled tests and acoustic emission measurements were also carried out. (orig.) (54 refs.).

  5. Summary report - development of laboratory tests and the stress- strain behaviour of Olkiluoto mica gneiss

    International Nuclear Information System (INIS)

    Hakala, M.; Heikkilae, E.

    1997-05-01

    This work summarizes the project aimed at developing and qualifying a suitable combination of laboratory tests to establish a statistically reliable stress-strain behaviour of the main rock types at Posiva Oy's detailed investigation sites for disposal of spent nuclear fuel. The work includes literature study of stress-strain behaviour of brittle rock, development and qualification of laboratory tests, suggested test procedures and interpretation methods and finally testing of Olkiluoto mica gneiss. The Olkiluoto study includes over 130 loading tests. Besides the commonly used laboratory tests, direct tensile tests, damage controlled tests and acoustic emission measurements were also carried out. (orig.) (54 refs.)

  6. Memory evaluation in mild cognitive impairment using recall and recognition tests

    OpenAIRE

    Bennett, IJ; Golob, EJ; Parker, ES; Starr, A

    2006-01-01

    Amnestic mild cognitive impairment (MCI) is a selective episodic memory deficit that often indicates early Alzheimer's disease. Episodic memory function in MCI is typically defined by deficits in free recall, but can also be tested using recognition procedures. To assess both recall and recognition in MCI, MCI (n = 21) and older comparison (n = 30) groups completed the USC-Repeatable Episodic Memory Test. Subjects memorized two verbally presented 15-item lists. One list was used for three fre...

  7. The recall of information from working memory : insights from behavioural and chronometric perspectives.

    OpenAIRE

    Towse, John N.; Cowan, Nelson; Hitch, Graham J.; Horton, Neil

    2008-01-01

    We describe and evaluate a recall reconstruction hypothesis for working memory (WM), according to which items can be recovered from multiple memory representations. Across four experiments, participants recalled memoranda that were either integrated with or independent of the sentence content. We found consistently longer pauses accompanying the correct recall of integrated compared with independent words, supporting the argument that sentence memory could scaffold the access of target items....

  8. Testing the effectiveness of group-based memory rehabilitation in chronic stroke patients.

    Science.gov (United States)

    Miller, Laurie A; Radford, Kylie

    2014-01-01

    Memory complaints are common after stroke, yet there have been very few studies of the outcome of memory rehabilitation in these patients. The present study evaluated the effectiveness of a new manualised, group-based memory training programme. Forty outpatients with a single-stroke history and ongoing memory complaints were enrolled. The six-week course involved education and strategy training and was evaluated using a wait-list crossover design, with three assessments conducted 12 weeks apart. Outcome measures included: tests of anterograde memory (Rey Auditory Verbal Learning Test: RAVLT; Complex Figure Test) and prospective memory (Royal Prince Alfred Prospective Memory Test); the Comprehensive Assessment of Prospective Memory (CAPM) questionnaire and self-report of number of strategies used. Significant training-related gains were found on RAVLT learning and delayed recall and on CAPM informant report. Lower baseline scores predicted greater gains for several outcome measures. Patients with higher IQ or level of education showed more gains in number of strategies used. Shorter time since onset was related to gains in prospective memory, but no other stroke-related variables influenced outcome. Our study provides evidence that a relatively brief, group-based training intervention can improve memory functioning in chronic stroke patients and clarified some of the baseline factors that influence outcome.

  9. Sexual-risk behaviour and HIV testing among Canadian snowbirds who winter in Florida.

    Science.gov (United States)

    Mairs, Katie; Bullock, Sandra L

    2013-06-01

    Rates of HIV (human immunodeficiency virus) and sexual-risk behaviour for those aged 50 and over in the United States are highest and increasing in Florida, where many Canadian "snowbirds" winter. This pilot study examined the sexual-risk behaviour and predictors of HIV testing in a convenience sample of Canadian snowbirds who winter in Florida (n = 265). Multivariate logistic regression analyses revealed that the odds of testing were increased for the unmarried, those aged 50-64, those who had talked to a doctor about sexual-risk behaviour since age 50, and those who agreed that sex was important in their lives. Dating males were more likely to test than non-dating males. Dating females were not more likely to test than non-dating females; and males who dated were 13.6 times more likely to test than females who dated. Further research will improve understanding of Canadian snowbirds' sexual interactions and HIV-testing behaviour.

  10. Processes of conscious and unconscious memory: evidence from current research on dissociation of memories within a test.

    Science.gov (United States)

    Cheng, Chao-Ming; Huang, Chin-Lan

    2011-01-01

    The processes of conscious memory (CM) and unconscious memory (UM) are explored, based on the results of the current and previous studies in which the 2 forms of memory within a test were separated by either the process dissociation or metacognition-based dissociation procedure. The results assessing influences of shallow and deep processing, association, and self-generation on CM in explicit and implicit tests are taken as evidence that CM in a test is driven not only conceptually but also by the driving nature of the test, and CM benefits from an encoding condition to the extent that information processing for CM recapitulates that engaged in the encoding condition.Those influences on UM in explicit and implicit tests are taken to support the view that UM in a test is driven by the nature of the test itself, and UM benefits from an encoding condition to the extent that the cognitive environments at test and at study match to activate the same type of information (e.g., visual, lexical, or semantic) about memory items or the same content of a preexisting association or categorical structure.

  11. Relationship Between the Wada Test and Preoperative/Postoperative Memory in Mesial Temporal Lobe Epilepsy Patients

    Directory of Open Access Journals (Sweden)

    Burcu POLAT

    2013-01-01

    Full Text Available Objectives: To study the correlation between Wada memory test and neuropsychometric tests which were applied preoperatively to mesialtemporal lobe epilepsy patients associated with hippocampal sclerosis (MTLE-HS who had undergone selective amygdalohippocampectomyand find out the effects of early onset epileptic seizures on atypical memory dominance.Methods: Drug-resistant 27 patients (16 left, 11 right MTLE-HS had video EEG, cranial MRI and Wada test preoperatively. Weschler visualsubtest and verbal memory processing tests were applied to all patients before surgery and the first year after the operation.Results: The number of left hemisphere memory dominant patients was 6 (22.2% and the number of atypical memory dominant patientswas 21 (77.8% according to the Wada test. There was a significant difference between the two groups when compared for epileptic seizureonset age; (p=0.042, and also a significant diffference when compared for HS (right/left side (p=0.002. When we analyzed the correlationbetween preoperative and postoperative verbal and nonverbal tests and left memory Wada dominance; in verbal memory processing tests‘delayed recall’ scores between groups were significant (p=0.042, on the other hand in patients with atypical memory dominance ‘total learning’ scores between groups were significant (p<0.001.Conclusion: As a result, we found that the earlier the onset of seizures, the more atypical the memory dominance (right or bilateral. The Wada test was effective for assessing verbal memory; on the other hand, it was inadequate for assessing visual memory dominance. If the scores of ‘delayed recall’ in verbal memory were high in the patients with typical verbal dominance and ‘total learning’ scores in the patients with atypical verbal dominance, the scores also tended to rise after the operation.

  12. Testing aggressive behaviour in a feeding context: Importance of ethologically relevant stimuli.

    Science.gov (United States)

    González, Daniel; Szenczi, Péter; Bánszegi, Oxána; Hudson, Robyn

    2018-05-01

    The choice of stimuli used in tests of animal behaviour can have a critical effect on the outcome. Here we report two experiments showing how different foods influenced aggressive behaviour in competition tests at weaning among littermates of the domestic cat. Whereas in Experiment 1 canned food elicited almost no overt competition, a piece of raw beef rib elicited clearly aggressive behaviour among littermates. In Experiment 2 the food stimuli were chosen to differ from raw beef rib in various combinations of taste/smell, texture and monopolizability. Kittens showed different levels of aggression in response to the five stimuli tested, which suggests that the strong effect of beef rib in eliciting aggressive behaviour was due to a complex combination of features. We suggest that using stimuli approximating the evolved, functional significance to the species concerned is more likely to result in robust, biologically relevant behaviours than more artificial stimuli. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. When unfamiliarity matters: Changing environmental context between study and test affects recognition memory for unfamiliar stimuli

    NARCIS (Netherlands)

    Russo, R.; Ward, G.; Geurts, H.M.; Scheres, A.P.J.

    1999-01-01

    Performance in recognition memory has been shown to be relatively insensitive to the effect of environmental context changes between study and test. Recent evidence (P. Dalton, 1993) showed that environmental context changes between study and test affected recognition memory discrimination for

  14. Why Is Test-Restudy Practice Beneficial for Memory? An Evaluation of the Mediator Shift Hypothesis

    Science.gov (United States)

    Pyc, Mary A.; Rawson, Katherine A.

    2012-01-01

    Although the memorial benefits of testing are well established empirically, the mechanisms underlying this benefit are not well understood. The authors evaluated the mediator shift hypothesis, which states that test-restudy practice is beneficial for memory because retrieval failures during practice allow individuals to evaluate the effectiveness…

  15. Behavioural and magnetoencephalographic evidence for the interaction between semantic and episodic memory in healthy elderly subjects.

    Science.gov (United States)

    La Corte, Valentina; Dalla Barba, Gianfranco; Lemaréchal, Jean-Didier; Garnero, Line; George, Nathalie

    2012-10-01

    The relationship between episodic and semantic memory systems has long been debated. Some authors argue that episodic memory is contingent on semantic memory (Tulving 1984), while others postulate that both systems are independent since they can be selectively damaged (Squire 1987). The interaction between these memory systems is particularly important in the elderly, since the dissociation of episodic and semantic memory defects characterize different aging-related pathologies. Here, we investigated the interaction between semantic knowledge and episodic memory processes associated with faces in elderly subjects using an experimental paradigm where the semantic encoding of famous and unknown faces was compared to their episodic recognition. Results showed that the level of semantic awareness of items affected the recognition of those items in the episodic memory task. Event-related magnetic fields confirmed this interaction between episodic and semantic memory: ERFs related to the old/new effect during the episodic task were markedly different for famous and unknown faces. The old/new effect for famous faces involved sustained activities maximal over right temporal sensors, showing a spatio-temporal pattern partly similar to that found for famous versus unknown faces during the semantic task. By contrast, an old/new effect for unknown faces was observed on left parieto-occipital sensors. These findings suggest that the episodic memory for famous faces activated the retrieval of stored semantic information, whereas it was based on items' perceptual features for unknown faces. Overall, our results show that semantic information interfered markedly with episodic memory processes and suggested that the neural substrates of these two memory systems overlap.

  16. A Pilot Study of a Test for Visual Recognition Memory in Adults with Moderate to Severe Intellectual Disability

    Science.gov (United States)

    Pyo, Geunyeong; Ala, Tom; Kyrouac, Gregory A.; Verhulst, Steven J.

    2010-01-01

    Objective assessment of memory functioning is an important part of evaluation for Dementia of Alzheimer Type (DAT). The revised Picture Recognition Memory Test (r-PRMT) is a test for visual recognition memory to assess memory functioning of persons with intellectual disabilities (ID), specifically targeting moderate to severe ID. A pilot study was…

  17. Overgeneral autobiographical memory and age of onset of childhood sexual abuse in patients with recurrent suicidal behaviour.

    Science.gov (United States)

    Crane, Catherine; Duggan, Danielle S

    2009-03-01

    To explore the association between age of onset of childhood sexual abuse (CSA) and overgeneral memory (OGM) in a clinical sample. Presence and age of onset of CSA and levels of OGM were assessed in 49 patients attending hospital following a recurrence of suicidal behaviour. Twenty six participants reported CSA. Earlier age of onset of CSA was associated with greater OGM, indexed by fewer specific and more categoric memories. The association was not accounted for either by elevated levels of depression in those reporting earlier abuse, nor by levels of general verbal fluency. The findings are consistent with previous work and support the hypothesis that abuse occurring earlier in development results in more pronounced OGM.

  18. Individual behavioural differences in pigs: intra- and inter-test consistency

    NARCIS (Netherlands)

    Spoolder, H.A.M.; Burbidge, J.A.; Lawrence, A.B.; Simmins, P.H.

    1996-01-01

    Two studies have been carried out in pigs to determine the relation between escape behaviour and production parameters and between escape behaviour and other factors. In the first, 823 piglets were tested with the backtest at 10 and 17 days of age. Production parameters, such as average daily weight

  19. NIH Toolbox Cognition Battery (NIHTB-CB): list sorting test to measure working memory.

    Science.gov (United States)

    Tulsky, David S; Carlozzi, Noelle; Chiaravalloti, Nancy D; Beaumont, Jennifer L; Kisala, Pamela A; Mungas, Dan; Conway, Kevin; Gershon, Richard

    2014-07-01

    The List Sorting Working Memory Test was designed to assess working memory (WM) as part of the NIH Toolbox Cognition Battery. List Sorting is a sequencing task requiring children and adults to sort and sequence stimuli that are presented visually and auditorily. Validation data are presented for 268 participants ages 20 to 85 years. A subset of participants (N=89) was retested 7 to 21 days later. As expected, the List Sorting Test had moderately high correlations with other measures of working memory and executive functioning (convergent validity) but a low correlation with a test of receptive vocabulary (discriminant validity). Furthermore, List Sorting demonstrates expected changes over the age span and has excellent test-retest reliability. Collectively, these results provide initial support for the construct validity of the List Sorting Working Memory Measure as a measure of working memory. However, the relationship between the List Sorting Test and general executive function has yet to be determined.

  20. When we test, do we stress? Impact of the testing environment on cortisol secretion and memory performance in older adults.

    Science.gov (United States)

    Sindi, Shireen; Fiocco, Alexandra J; Juster, Robert-Paul; Pruessner, Jens; Lupien, Sonia J

    2013-08-01

    The majority of studies find that older adults have worse memory performance than young adults. However, contextual features in the testing environment may be perceived as stressful by older adults, increasing their stress hormone levels. Given the evidence that older adults are highly sensitive to the effects of stress hormones (cortisol) on memory performance, it is postulated that a stressful testing environment in older adults can lead to an acute stress response and to memory impairments. The current study compared salivary cortisol levels and memory performance in young and older adults tested in environments manipulated to be stressful (unfavourable condition) or not stressful (favourable condition) for each age group. 28 young adults and 32 older adults were tested in two testing conditions: (1) a condition favouring young adults (constructed to be less stressful for young adults), and (2) a condition favouring older adults (constructed to be less stressful for older adults). The main outcome measure was salivary cortisol levels. Additionally, immediate and delayed memory performances were assessed during each condition. In older adults only, we found significantly high cortisol levels and low memory performance in the condition favouring young adults. In contrast, cortisol levels were lower and memory performance was better when older adults were tested in conditions favouring them. There was no effect of testing condition in young adults. The results demonstrate that older adults' memory performance is highly sensitive to the testing environment. These findings have important implications for both research and clinical settings in which older adults are tested for memory performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Low dose prenatal alcohol exposure does not impair spatial learning and memory in two tests in adult and aged rats.

    Directory of Open Access Journals (Sweden)

    Carlie L Cullen

    Full Text Available Consumption of alcohol during pregnancy can have detrimental impacts on the developing hippocampus, which can lead to deficits in learning and memory function. Although high levels of alcohol exposure can lead to severe deficits, there is a lack of research examining the effects of low levels of exposure. This study used a rat model to determine if prenatal exposure to chronic low dose ethanol would result in deficits in learning and memory performance and if this was associated with morphological changes within the hippocampus. Sprague Dawley rats were fed a liquid diet containing 6% (vol/vol ethanol (EtOH or an isocaloric control diet throughout gestation. Male and Female offspring underwent behavioural testing at 8 (Adult or 15 months (Aged of age. Brains from these animals were collected for stereological analysis of pyramidal neuron number and dendritic morphology within the CA1 and CA3 regions of the dorsal hippocampus. Prenatal ethanol exposed animals did not differ in spatial learning or memory performance in the Morris water maze or Y maze tasks compared to Control offspring. There was no effect of prenatal ethanol exposure on pyramidal cell number or density within the dorsal hippocampus. Overall, this study indicates that chronic low dose prenatal ethanol exposure in this model does not have long term detrimental effects on pyramidal cells within the dorsal hippocampus or impair spatial learning and memory performance.

  2. Brief description of out-of-pile test facilities for study in corrosion and fission product behaviour in flowing sodium

    International Nuclear Information System (INIS)

    Iizawa, K.; Sekiguchi, N.; Atsumo, H.

    1976-01-01

    The experimental methods to perform tests for study in corrosion and fission products behaviour in flowing sodium are outlined. Flow diagrams for the activated materials and fission products behaviour test loop are given

  3. Computerised working memory based cognitive remediation therapy does not affect Reading the Mind in the Eyes test performance or neural activity during a Facial Emotion Recognition test in psychosis.

    Science.gov (United States)

    Mothersill, David; Dillon, Rachael; Hargreaves, April; Castorina, Marco; Furey, Emilia; Fagan, Andrew J; Meaney, James F; Fitzmaurice, Brian; Hallahan, Brian; McDonald, Colm; Wykes, Til; Corvin, Aiden; Robertson, Ian H; Donohoe, Gary

    2018-05-27

    Working memory based cognitive remediation therapy (CT) for psychosis has recently been associated with broad improvements in performance on untrained tasks measuring working memory, episodic memory and IQ, and changes in associated brain regions. However, it is unclear if these improvements transfer to the domain of social cognition and neural activity related to performance on social cognitive tasks. We examined performance on the Reading the Mind in the Eyes test (Eyes test) in a large sample of participants with psychosis who underwent working memory based CT (N = 43) compared to a Control Group of participants with psychosis (N = 35). In a subset of this sample, we used functional magnetic resonance imaging (fMRI) to examine changes in neural activity during a facial emotion recognition task in participants who underwent CT (N = 15) compared to a Control Group (N = 15). No significant effects of CT were observed on Eyes test performance or on neural activity during facial emotion recognition, either at pworking memory based CT does not significantly impact an aspect of social cognition which was measured behaviourally and neurally. It provides further evidence that deficits in the ability to decode mental state from facial expressions are dissociable from working memory deficits, and suggests that future CT programs should target social cognition in addition to working memory for the purposes of further enhancing social function. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  4. NI Based System for Seu Testing of Memory Chips for Avionics

    Directory of Open Access Journals (Sweden)

    Boruzdina Anna

    2016-01-01

    Full Text Available This paper presents the results of implementation of National Instrument based system for Single Event Upset testing of memory chips into neutron generator experimental facility, which used for SEU tests for avionics purposes. Basic SEU testing algorithm with error correction and constant errors detection is presented. The issues of radiation shielding of NI based system are discussed and solved. The examples of experimental results show the applicability of the presented system for SEU memory testing under neutrons influence.

  5. Influence of memory, attention, IQ and age on auditory temporal processing tests: preliminary study

    OpenAIRE

    Murphy, Cristina Ferraz Borges; Zachi, Elaine Cristina; Roque, Daniela Tsubota; Ventura, Dora Selma Fix; Schochat, Eliane

    2014-01-01

    PURPOSE: To investigate the existence of correlations between the performance of children in auditory temporal tests (Frequency Pattern and Gaps in Noise - GIN) and IQ, attention, memory and age measurements. METHOD: Fifteen typically developing individuals between the ages of 7 to 12 years and normal hearing participated in the study. Auditory temporal processing tests (GIN and Frequency Pattern), as well as a Memory test (Digit Span), Attention tests (auditory and visual modality) and ...

  6. Memory outcome following left anterior temporal lobectomy in patients with a failed Wada test.

    Science.gov (United States)

    Rathore, Chaturbhuj; Alexander, Aley; Sarma, P Sankara; Radhakrishnan, Kurupath

    2015-03-01

    This study aimed to compare the memory outcome following left anterior temporal lobectomy (ATL) between patients with a failed Wada test and patients who passed the Wada test. From 1996 to 2002, we performed the Wada test on all patients with unilateral left mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) and concordant electroclinical data before ATL. We used a 12-item recognition paradigm for memory testing and awarded a score of +1 for each correct response and -0.5 for each incorrect response. No patient was denied surgery on the basis of Wada scores. We assessed cognitive and memory functions using the Wechsler Adult Intelligence Scale and the Wechsler Memory Scale preoperatively and at one year after ATL. We compared the number of patients who showed decline in memory scores, as per the published reliable change indices, between the patients with a failed Wada test and the patients who passed the Wada test. Out of the 116 eligible patients with left MTLE-HS, 88 underwent bilateral Wada test, while 28 underwent ipsilateral Wada test. None of them developed postoperative amnesia. Approximately, one-third of patients with a failed Wada memory test when the failure was defined as a contralateral score of 8, and as an asymmetry score of failed Wada memory test and the group who passed the Wada memory test. The results remained the same when analyses were repeated at various other cutoff points. The patients with left MTLE-HS with concordant electroclinical, MRI, and neuropsychological data should not be denied ATL solely on the basis of Wada memory test results. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Testing declarative memory in laboratory rats and mice using the nonconditioned social discrimination procedure.

    Science.gov (United States)

    Engelmann, Mario; Hädicke, Jana; Noack, Julia

    2011-07-14

    Testing declarative memory in laboratory rodents can provide insights into the fundamental mechanisms underlying this type of learning and memory processing, and these insights are likely to be applicable to humans. Here we provide a detailed description of the social discrimination procedure used to investigate recognition memory in rats and mice, as established during the last 20 years in our laboratory. The test is based on the use of olfactory signals for social communication in rodents; this involves a direct encounter between conspecifics, during which the investigatory behavior of the experimental subject serves as an index for learning and memory performance. The procedure is inexpensive, fast and very reliable, but it requires well-trained human observers. We include recent modifications to the procedure that allow memory extinction to be investigated by retroactive and proactive interference, and that enable the dissociated analysis of the central nervous processing of the volatile fraction of an individual's olfactory signature. Depending on the memory retention interval under study (short-term memory, intermediate-term memory, long-term memory or long-lasting memory), the protocol takes ~10 min or up to several days to complete.

  8. Comparison of accelerated pavement test results with long term pavement behaviour and performance

    CSIR Research Space (South Africa)

    Jooste, FJ

    1997-08-01

    Full Text Available The aim of this study was to investigate the following:how accelerated pavement testing predictions compare with actual road behaviour and performance the relative influences of load and environmental factors on pavement deterioration and how well...

  9. Behaviour of (Th, U)O2 microspheres under compression tests and pelletization

    International Nuclear Information System (INIS)

    Ferreira, R.A.N.

    1982-12-01

    The interrelation between the behaviour of isolated microspheres in compression tests and the microstructure of sintered pellets obtained with these microspheres, was investigated. Various batches of (Th, 5 w/o U)O 2 microspheres were produced applying the so-called gel process. The production parameters were diversified both as to the composition and to the heat treatments. The resulting products underwent compression tests in an universal tension and compression machine as single microspheres and, as bulk material, were compacted and sintered. The results of the compression tests revealed the existence of two distinct classes of fragmentation behaviour. Each of these classes causes a distinct behaviour during the pelletization, too, resulting in fuel pellets with quite different microstructures. It was evidenced that there is a relationship between these differences in the microstructure and the behaviour of the single microspheres in the compression test. (Author) [pt

  10. Study of creep behaviour in P-doped copper with slow strain rate tensile tests

    International Nuclear Information System (INIS)

    Xuexing Yao; Sandstroem, Rolf

    2000-08-01

    Pure copper with addition of phosphorous is planned to be used to construct the canisters for spent nuclear fuel. The copper canisters can be exposed to a creep deformation up to 2-4% at temperatures in services. The ordinary creep strain tests with dead weight loading are generally employed to study the creep behaviour; however, it is reported that an initial plastic deformation of 5-15% takes place when loading the creep specimens at lower temperatures. The slow strain rate tensile test is an alternative to study creep deformation behaviour of materials. Ordinary creep test and slow strain rate tensile test can give the same information in the secondary creep stage. The advantage of the tensile test is that the starting phase is much more controlled than in a creep test. In a tensile test the initial deformation behaviour can be determined and the initial strain of less than 5% can be modelled. In this study slow strain rate tensile tests at strain rate of 10 -4 , 10 -5 , 10 -6 , and 10 -7 /s at 75, 125 and 175 degrees C have been performed on P-doped pure Cu to supplement creep data from conventional creep tests. The deformation behaviour has successfully been modelled. It is shown that the slow strain rate tensile tests can be implemented to study the creep deformation behaviours of pure Cu

  11. Habitat stability, predation risk and ‘memory syndromes’

    OpenAIRE

    S. Dalesman; A. Rendle; S.R.X. Dall

    2015-01-01

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonst...

  12. Concept of scaled test facility for simulating the PWR thermalhydraulic behaviour

    International Nuclear Information System (INIS)

    Silva Filho, E.

    1990-01-01

    This work deals with the design of a scaled test facility of a typical pressurized water reactor plant, to simulation of small break Loss-of-Coolant Accident. The computer code RELAP 5/ MOD1 has been utilized to simulate the accident and to compare the test facility behaviour with the reactor plant one. The results demonstrate similar thermal-hydraulic behaviours of the two sistema. (author)

  13. A Working Memory Test Battery: Java-Based Collection of Seven Working Memory Tasks

    Directory of Open Access Journals (Sweden)

    James M Stone

    2015-06-01

    Full Text Available Working memory is a key construct within cognitive science. It is an important theory in its own right, but the influence of working memory is enriched due to the widespread evidence that measures of its capacity are linked to a variety of functions in wider cognition. To facilitate the active research environment into this topic, we describe seven computer-based tasks that provide estimates of short-term and working memory incorporating both visuospatial and verbal material. The memory span tasks provided are; digit span, matrix span, arrow span, reading span, operation span, rotation span, and symmetry span. These tasks are built to be simple to use, flexible to adapt to the specific needs of the research design, and are open source. All files can be downloaded from the project website http://www.cognitivetools.uk and the source code is available via Github.

  14. Computerized visuo-spatial memory test as a supplementary screening test for dementia.

    Science.gov (United States)

    Maki, Yohko; Yoshida, Hiroshi; Yamaguchi, Haruyasu

    2010-06-01

    To prepare for a super-aging society, effective dementia screening tests are required. The most salient deficit appearing from the early stages of dementia/Alzheimer's disease (AD) is a deterioration in memory. The Hasegawa Dementia Scale-revised (HDS-R) and the Mini-Mental State Examination (MMSE) are widely used in Japan to screen for dementia. Both place an emphasis on memory function, but neither examines visuo-spatial memory (VSM) function, even though VSM deficits are a sensitive marker for the detection of conversion to dementia. Furthermore, brief tests of VSM that are appropriate for screening have not been standardized. Thus, in the present study, we devised a brief, computer-aided short-term VSM test. Sixty-six aged people were evaluated. Using the Clinical Dementia Rating (CDR), it was found that 29 could be considered normal controls (NC; CDR 0), 10 had mild cognitive impairment (MCI; CDR 0.5), 15 had mild dementia (CDR 1), and 12 had moderate to severe dementia (CDR 2-3). The VSM test estimated how many locations each subject could memorize. Several numbered circles were shown on a monitor and subjects were required to memorize the location of these circles sequentially. After the numbers on the circles on the screen had disappeared, the subjects were required to indicate the circles in ascending order. A touch panel screen was used for this test to make it easier. The HDS-R was applied to subjects with MCI and dementia. The mean (+/-SD) VSM score in subjects with MCI (5.70 +/- 0.96) was significantly lower than that in NC subjects (6.69 +/- 0.82), but significantly higher than that in subjects classified as CDR 1 (4.67 +/- 0.87). There was no significant difference in VSM scores between subjects classified as CDR 1 and CDR 2-3 (3.80 +/- 0.80). There was a moderate significant correlation between VSM and HDS-R scores. In the present study, the VSM test detected differences in VSM function among NC subjects and subjects with MCI and mild dementia. The

  15. Retest effects in working memory capacity tests: A meta-analysis.

    Science.gov (United States)

    Scharfen, Jana; Jansen, Katrin; Holling, Heinz

    2018-06-15

    The repeated administration of working memory capacity tests is common in clinical and research settings. For cognitive ability tests and different neuropsychological tests, meta-analyses have shown that they are prone to retest effects, which have to be accounted for when interpreting retest scores. Using a multilevel approach, this meta-analysis aims at showing the reproducibility of retest effects in working memory capacity tests for up to seven test administrations, and examines the impact of the length of the test-retest interval, test modality, equivalence of test forms and participant age on the size of retest effects. Furthermore, it is assessed whether the size of retest effects depends on the test paradigm. An extensive literature search revealed 234 effect sizes from 95 samples and 68 studies, in which healthy participants between 12 and 70 years repeatedly performed a working memory capacity test. Results yield a weighted average of g = 0.28 for retest effects from the first to the second test administration, and a significant increase in effect sizes was observed up to the fourth test administration. The length of the test-retest interval and publication year were found to moderate the size of retest effects. Retest effects differed between the paradigms of working memory capacity tests. These findings call for the development and use of appropriate experimental or statistical methods to address retest effects in working memory capacity tests.

  16. Visual Working Memory and Number Sense: Testing the Double Deficit Hypothesis in Mathematics

    Science.gov (United States)

    Toll, Sylke W. M.; Kroesbergen, Evelyn H.; Van Luit, Johannes E. H.

    2016-01-01

    Background: Evidence exists that there are two main underlying cognitive factors in mathematical difficulties: working memory and number sense. It is suggested that real math difficulties appear when both working memory and number sense are weak, here referred to as the double deficit (DD) hypothesis. Aims: The aim of this study was to test the DD…

  17. Increased Task Demand during Spatial Memory Testing Recruits the Anterior Cingulate Cortex

    Science.gov (United States)

    Carr, Joshua K.; Fournier, Neil M.; Lehmann, Hugo

    2016-01-01

    We examined whether increasing retrieval difficulty in a spatial memory task would promote the recruitment of the anterior cingulate cortex (ACC) similar to what is typically observed during remote memory retrieval. Rats were trained on the hidden platform version of the Morris Water Task and tested three or 30 d later. Retrieval difficulty was…

  18. Intrusions and provoked and spontaneous confabulations on memory tests in Korsakoff's syndrome

    NARCIS (Netherlands)

    Rensen, Y.C.M.; Oosterman, J.M.; Walvoort, S.J.W.; Eling, P.A.T.M.; Kessels, R.P.C.

    2017-01-01

    Introduction: Intrusions on verbal memory tests have been used as an index for clinical confabulation. Severe memory impairments in combination with executive dysfunction have been suggested to be the underlying mechanism of confabulation, but to date, this relation is unclear. The aim of this study

  19. A match-mismatch test of a stage model of behaviour change in tobacco smoking

    NARCIS (Netherlands)

    Dijkstra, A; Conijn, B; De Vries, H

    Aims An innovation offered by stage models of behaviour change is that of stage-matched interventions. Match-mismatch studies are the primary test of this idea but also the primary test of the validity of stage models. This study aimed at conducting such a test among tobacco smokers using the Social

  20. Collaboration can improve individual recognition memory: evidence from immediate and delayed tests.

    Science.gov (United States)

    Rajaram, Suparna; Pereira-Pasarin, Luciane P

    2007-02-01

    In two experiments, we tested the effects of collaboration on individual recognition memory. In Experiment 1, participants studied pictures and words either for meaning or for surface properties and made recognition memory judgments individually either following group discussion among 3 members (collaborative condition) or in the absence of discussion (noncollaborative condition). Levels of processing and picture superiority effects were replicated, and collaboration significantly increased individual recognition memory. Experiment 2 replicated this positive effect and showed that even though memory sensitivity declined at longer delays (48 h and 1 week), collaboration continued to exert a positive influence. These findings show that (1) consensus is not necessary for producing benefits of collaboration on individual recognition, (2) collaborative facilitation on individual memory is robust, and (3) collaboration enhances individual memory further if conditions predispose individual accuracy in the absence of collaboration.

  1. Effects of temperature changes and stress loading on the mechanical and shape memory properties of thermoplastic materials with different glass transition behaviours and crystal structures.

    Science.gov (United States)

    Iijima, Masahiro; Kohda, Naohisa; Kawaguchi, Kyotaro; Muguruma, Takeshi; Ohta, Mitsuru; Naganishi, Atsuko; Murakami, Takashi; Mizoguchi, Itaru

    2015-12-01

    To investigate the effects of temperature changes and stress loading on the mechanical and shape memory properties of thermoplastic materials with different glass transition behaviours and crystal structures. Five thermoplastic materials, polyethylene terephthalate glycol (Duran®, Scheu Dental), polypropylene (Hardcast®, Scheu Dental), and polyurethane (SMP MM®, SMP Technologies) with three different glass transition temperatures (T g) were selected. The T g and crystal structure were assessed using differential scanning calorimetry and X-ray diffraction. The deterioration of mechanical properties by thermal cycling and the orthodontic forces during stepwise temperature changes were investigated using nanoindentation testing and custom-made force-measuring system. The mechanical properties were also evaluated by three-point bending tests; shape recovery with heating was then investigated. The mechanical properties for each material were decreased significantly by 2500 cycles and great decrease was observed for Hardcast (crystal plastic) with higher T g (155.5°C) and PU 1 (crystalline or semi-crystalline plastic) with lower T g (29.6°C). The Duran, PU 2, and PU 3 with intermediate T g (75.3°C for Duran, 56.5°C for PU 2, and 80.7°C for PU 3) showed relatively stable mechanical properties with thermal cycling. The polyurethane polymers showed perfect shape memory effect within the range of intraoral temperature changes. The orthodontic force produced by thermoplastic appliances decreased with the stepwise temperature change for all materials. Orthodontic forces delivered by thermoplastic appliances may influence by the T g of the materials, but not the crystal structure. Polyurethane is attractive thermoplastic materials due to their unique shape memory phenomenon, but stress relaxation with temperature changes is expected. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For

  2. Preliminary Validation of a New Measure of Negative Response Bias: The Temporal Memory Sequence Test.

    Science.gov (United States)

    Hegedish, Omer; Kivilis, Naama; Hoofien, Dan

    2015-01-01

    The Temporal Memory Sequence Test (TMST) is a new measure of negative response bias (NRB) that was developed to enrich the forced-choice paradigm. The TMST does not resemble the common structure of forced-choice tests and is presented as a temporal recall memory test. The validation sample consisted of 81 participants: 21 healthy control participants, 20 coached simulators, and 40 patients with acquired brain injury (ABI). The TMST had high reliability and significantly high positive correlations with the Test of Memory Malingering and Word Memory Test effort scales. Moreover, the TMST effort scales exhibited high negative correlations with the Glasgow Coma Scale, thus validating the previously reported association between probable malingering and mild traumatic brain injury. A suggested cutoff score yielded acceptable classification rates in the ABI group as well as in the simulator and control groups. The TMST appears to be a promising measure of NRB detection, with respectable rates of reliability and construct and criterion validity.

  3. Fatigue crack behaviour: comparing three-point bend test and wedge splitting test data on vibrated concrete using Paris' law

    Czech Academy of Sciences Publication Activity Database

    Seitl, Stanislav; Thienpont, T.; De Corte, W.

    2017-01-01

    Roč. 11, č. 39 (2017), s. 110-117 ISSN 1971-8993 R&D Projects: GA MŠk LM2015069 Institutional support: RVO:68081723 Keywords : Fatigue crack behaviour * Tree-point bending test * Wedge splitting test * Self-compacting concrete Subject RIV: JL - Materials Fatigue, Friction Mechanics OBOR OECD: Audio engineering, reliability analysis

  4. The (Spatial) Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition.

    Science.gov (United States)

    Gudde, Harmen B; Griffiths, Debra; Coventry, Kenny R

    2018-02-19

    The memory game paradigm is a behavioral procedure to explore the relationship between language, spatial memory, and object knowledge. Using two different versions of the paradigm, spatial language use and memory for object location are tested under different, experimentally manipulated conditions. This allows us to tease apart proposed models explaining the influence of object knowledge on spatial language (e.g., spatial demonstratives), and spatial memory, as well as understanding the parameters that affect demonstrative choice and spatial memory more broadly. Key to the development of the method was the need to collect data on language use (e.g., spatial demonstratives: "this/that") and spatial memory data under strictly controlled conditions, while retaining a degree of ecological validity. The language version (section 3.1) of the memory game tests how conditions affect language use. Participants refer verbally to objects placed at different locations (e.g., using spatial demonstratives: "this/that red circle"). Different parameters can be experimentally manipulated: the distance from the participant, the position of a conspecific, and for example whether the participant owns, knows, or sees the object while referring to it. The same parameters can be manipulated in the memory version of the memory game (section 3.2). This version tests the effects of the different conditions on object-location memory. Following object placement, participants get 10 seconds to memorize the object's location. After the object and location cues are removed, participants verbally direct the experimenter to move a stick to indicate where the object was. The difference between the memorized and the actual location shows the direction and strength of the memory error, allowing comparisons between the influences of the respective parameters.

  5. The recall of information from working memory. Insights from behavioural and chronometric perspectives.

    Science.gov (United States)

    Towse, John N; Cowan, Nelson; Hitch, Graham J; Horton, Neil J

    2008-01-01

    We describe and evaluate a recall reconstruction hypothesis for working memory (WM), according to which items can be recovered from multiple memory representations. Across four experiments, participants recalled memoranda that were either integrated with or independent of the sentence content. We found consistently longer pauses accompanying the correct recall of integrated compared with independent words, supporting the argument that sentence memory could scaffold the access of target items. Integrated words were also more likely to be recalled correctly, dependent on the details of the task. Experiment 1 investigated the chronometry of spoken recall for word span and reading span, with participants completing an unfinished sentence in the latter case. Experiments 2 and 3 confirm recall time differences without using word generation requirements, while Experiment 4 used an item and order response choice paradigm with nonspoken responses. Data emphasise the value of recall timing in constraining theories of WM functioning.

  6. Construct validity of the Free and Cued Selective Reminding Test in older adults with memory complaints.

    Science.gov (United States)

    Clerici, Francesca; Ghiretti, Roberta; Di Pucchio, Alessandra; Pomati, Simone; Cucumo, Valentina; Marcone, Alessandra; Vanacore, Nicola; Mariani, Claudio; Cappa, Stefano Francesco

    2017-06-01

    The Free and Cued Selective Reminding Test (FCSRT) is the memory test recommended by the International Working Group on Alzheimer's disease (AD) for the detection of amnestic syndrome of the medial temporal type in prodromal AD. Assessing the construct validity and internal consistency of the Italian version of the FCSRT is thus crucial. The FCSRT was administered to 338 community-dwelling participants with memory complaints (57% females, age 74.5 ± 7.7 years), including 34 with AD, 203 with Mild Cognitive Impairment, and 101 with Subjective Memory Impairment. Internal Consistency was estimated using Cronbach's alpha coefficient. To assess convergent validity, five FCSRT scores (Immediate Free Recall, Immediate Total Recall, Delayed Free Recall, Delayed Total Recall, and Index of Sensitivity of Cueing) were correlated with three well-validated memory tests: Story Recall, Rey Auditory Verbal Learning test, and Rey Complex Figure (RCF) recall (partial correlation analysis). To assess divergent validity, a principal component analysis (an exploratory factor analysis) was performed including, in addition to the above-mentioned memory tasks, the following tests: Word Fluencies, RCF copy, Clock Drawing Test, Trail Making Test, Frontal Assessment Battery, Raven Coloured Progressive Matrices, and Stroop Colour-Word Test. Cronbach's alpha coefficients for immediate recalls (IFR and ITR) and delayed recalls (DFR and DTR) were, respectively, .84 and .81. All FCSRT scores were highly correlated with those of the three well-validated memory tests. The factor analysis showed that the FCSRT does not load on the factors saturated by non-memory tests. These findings indicate that the FCSRT has a good internal consistency and has an excellent construct validity as an episodic memory measure. © 2015 The British Psychological Society.

  7. Bridging naturalistic and laboratory assessment of memory: the Baycrest mask fit test.

    Science.gov (United States)

    Armson, Michael J; Abdi, Hervé; Levine, Brian

    2017-09-01

    Autobiographical memory tests provide a naturalistic counterpoint to the artificiality of laboratory research methods, yet autobiographical events are uncontrolled and, in most cases, unverifiable. In this study, we capitalised on a scripted, complex naturalistic event - the mask fit test (MFT), a standardised procedure required of hospital employees - to bridge the gap between naturalistic and laboratory memory assessment. We created a test of recognition memory for the MFT and administered it to 135 hospital employees who had undertaken the MFT at various points over the past five years. Multivariate analysis revealed two dimensions defined by accuracy and response bias. Accuracy scores showed the expected relationship to encoding-test delay, supporting the validity of this measure. Relative to younger adults, older adults' memory for this naturalistic event was better than would be predicted from the cognitive ageing literature, a result consistent with the notion that older adults' memory performance is enhanced when stimuli are naturalistic and personally relevant. These results demonstrate that testing recognition memory for a scripted event is a viable method of studying autobiographical memory.

  8. An empirical test of the Theory of Planned Behaviour applied to contraceptive use in rural Uganda.

    Science.gov (United States)

    Kiene, Susan M; Hopwood, Sarah; Lule, Haruna; Wanyenze, Rhoda K

    2014-12-01

    There is a high unmet need for contraceptives in developing countries such as Uganda, with high population growth, where efforts are needed to promote family planning and contraceptive use. Despite this high need, little research has investigated applications of health-behaviour-change theories to contraceptive use among this population. This study tested the Theory of Planned Behaviour's ability to predict contraceptive-use-related behaviours among post-partum women in rural Uganda. Results gave modest support to the theory's application and suggest an urgent need for improved theory-based interventions to promote contraceptive use in the populations of developing countries. © The Author(s) 2013.

  9. Semantic Memory Redux: An Experimental Test of Hierarchical Category Representation

    Science.gov (United States)

    Murphy, Gregory L.; Hampton, James A.; Milovanovic, Goran S.

    2012-01-01

    Four experiments investigated the classic issue in semantic memory of whether people organize categorical information in hierarchies and use inference to retrieve information from them, as proposed by Collins and Quillian (1969). Past evidence has focused on RT to confirm sentences such as "All birds are animals" or "Canaries breathe." However,…

  10. Can Survival Processing Enhance Story Memory? Testing the Generalizability of the Adaptive Memory Framework

    Science.gov (United States)

    Seamon, John G.; Bohn, Justin M.; Coddington, Inslee E.; Ebling, Maritza C.; Grund, Ethan M.; Haring, Catherine T.; Jang, Sue-Jung; Kim, Daniel; Liong, Christopher; Paley, Frances M.; Pang, Luke K.; Siddique, Ashik H.

    2012-01-01

    Research from the adaptive memory framework shows that thinking about words in terms of their survival value in an incidental learning task enhances their free recall relative to other semantic encoding strategies and intentional learning (Nairne, Pandeirada, & Thompson, 2008). We found similar results. When participants used incidental…

  11. On the Relationship between Memory and Perception: Sequential Dependencies in Recognition Memory Testing

    Science.gov (United States)

    Malmberg, Kenneth J.; Annis, Jeffrey

    2012-01-01

    Many models of recognition are derived from models originally applied to perception tasks, which assume that decisions from trial to trial are independent. While the independence assumption is violated for many perception tasks, we present the results of several experiments intended to relate memory and perception by exploring sequential…

  12. Memory detection 2.0: The first web-based memory detection test

    NARCIS (Netherlands)

    Kleinberg, B.; Verschuere, B.

    2015-01-01

    There is accumulating evidence that reaction times (RTs) can be used to detect recognition of critical (e.g., crime) information. A limitation of this research base is its reliance upon small samples (average n = 24), and indications of publication bias. To advance RT-based memory detection, we

  13. Testing a novel account of the dissociation between self-reported memory problems and memory performance in chemotherapy-treated breast cancer survivors.

    Science.gov (United States)

    Paquet, Lise; Verma, Shailendra; Collins, Barbara; Chinneck, Anne; Bedard, Marc; Song, Xinni

    2018-01-01

    A puzzling observation pertaining to the impact of breast cancer on memory is the frequently reported dissociation between breast cancer survivors' self-reported memory problems and memory performance. We evaluated the hypothesis that the dissociation is related to the fact that the objective memory measures previously used assessed retrospective memory (RM) and did not tap prospective memory (PM), a domain about which survivors are complaining. In a case-healthy-control (N = 80) cross-sectional study, the Memory for Intention Screening Test was used to assess PM and the Wechsler Logical Memory Test was used to evaluate RM. Self-reported problems were assessed with the Prospective and Retrospective Memory Questionnaire. Measures of depression (Center for Epidemiologic Studies Depression Scale) and fatigue (Functional Assessment of Cancer Therapy: Fatigue) were also administered. Both groups reported more PM than RM problems (P memory problems than controls (all P memory problems. Although unrelated to performance, memory complaints should not be dismissed, as they are closely associated with depression and fatigue and reveal an important facet of the cancer experience. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Transfer of training from one working memory task to another: Behavioural and neural evidence

    Directory of Open Access Journals (Sweden)

    Erin L. Beatty

    2015-06-01

    Full Text Available N-back working memory (WM tasks necessitate the maintenance and updating of dynamic rehearsal sets during performance. The delayed matching-to-sample (dMTS task is another WM task, which in turn involves the encoding, maintenance, and retrieval of stimulus representations in sequential order. Because both n-back and dMTS engage WM function, we hypothesized that compared to a control task not taxing WM, training on the n-back task would be associated with better performance on dMTS by virtue of training a shared mental capacity. We tested this hypothesis by randomly assigning subjects (N = 43 to train on either the n-back (including 2-back and 3-back levels or an active control task. Following training, dMTS was administered in the fMRI scanner. The n-back group performed marginally better than the active control group on dMTS. In addition, although the n-back group improved more on the less difficult 2-back level than the more difficult 3-back level across training sessions, it was improvement on the 3-back level that accounted for 21% of the variance in dMTS performance. For the control group, improvement in training across sessions was unrelated to dMTS performance. At the neural level, greater activation in the left inferior frontal gyrus, right posterior parietal cortex and the cerebellum distinguished the n-back group from the control group in the maintenance phase of dMTS. Degree of improvement on the 3-back level across training sessions was correlated with activation in right lateral prefrontal and motor cortices in the maintenance phase of dMTS. Our results suggest that although n-back training is more likely to improve performance in easier blocks, it is improvement in more difficult blocks that is predictive of performance on a target task drawing on WM. In addition, the extent to which training on a task can transfer to another task is likely due to the engagement of shared cognitive capacities and underlying neural substrates

  15. Free Recall Behaviour in Children with and without Spelling Impairment: The Impact of Working Memory Subcapacities

    Science.gov (United States)

    Malstadt, Nadine; Hasselhorn, Marcus; Lehmann, Martin

    2012-01-01

    This study examined supraspan free recall in children with and without spelling impairment. A repeated free recall task involving overt rehearsal and three computer-based adaptive working memory tasks were administered to 54 eight-year-old children. Children without spelling impairments tended to recall more items than did those children with…

  16. Long memory and changing persistence

    DEFF Research Database (Denmark)

    Kruse, Robinson; Sibbertsen, Philipp

    We study the empirical behaviour of semi-parametric log-periodogram estimation for long memory models when the true process exhibits a change in persistence. Simulation results confirm theoretical arguments which suggest that evidence for long memory is likely to be found. A recently proposed test...... by Sibbertsen and Kruse (2009) is shown to exhibit noticeable power to discriminate between long memory and a structural change in autoregressive parameters....

  17. The Third Dryout Fuel Behaviour Test Series in IFA-613

    International Nuclear Information System (INIS)

    Ianiri, Raffaella

    1998-02-01

    The objective of the dryout experiment with the instrumented fuel assembly IFA-613 is to provide information on the consequences induced on fuel by short terms dry outs having characteristics similar to those anticipated to occur from pump trips in a Boiling Water Reactor (BWR). For the third experiment it was planned to test one fresh and two pre-irradiated segments. Unfortunately one of the channels, Channel A developed a leakage and was not suitable for testing anymore. The rig was loaded with only two rods: one fresh PWR rod with a design similar to the fresh rod in IFA-613.1 and one pre-irradiated PWR segment (N1310 with a burn-up of 29 MWd/kgU). Both rods were equipped with a clad extensometer and two clad surface thermocouples (upper and lower position). The rig was loaded during the December 1997 shutdown and the dryout tests were performed on 16th January 1998. Both rods experienced temperature excursions with a target peak clad temperature (PCT) of 650 o C. According to the measured cladding temperatures, the time above the target temperature was about 4-5 s for both rods. The lower thermocouple did not indicate dryout at any occasion. The rig was unloaded immediately after the testing. (author)

  18. Method matters: systematic effects of testing procedure on visual working memory sensitivity.

    Science.gov (United States)

    Makovski, Tal; Watson, Leah M; Koutstaal, Wilma; Jiang, Yuhong V

    2010-11-01

    Visual working memory (WM) is traditionally considered a robust form of visual representation that survives changes in object motion, observer's position, and other visual transients. This article presents data that are inconsistent with the traditional view. We show that memory sensitivity is dramatically influenced by small variations in the testing procedure, supporting the idea that representations in visual WM are susceptible to interference from testing. In the study, participants were shown an array of colors to remember. After a short retention interval, memory for one of the items was tested with either a same-different task or a 2-alternative-forced-choice (2AFC) task. Memory sensitivity was much lower in the 2AFC task than in the same-different task. This difference was found regardless of encoding similarity or of whether visual WM required a fine or coarse memory resolution. The 2AFC disadvantage was reduced when participants were informed shortly before testing which item would be probed. The 2AFC disadvantage diminished in perceptual tasks and was not found in tasks probing visual long-term memory. These results support memory models that acknowledge the labile nature of visual WM and have implications for the format of visual WM and its assessment. (c) 2010 APA, all rights reserved

  19. The paced auditory serial addition test for working memory assessment: Psychometric properties

    Science.gov (United States)

    Nikravesh, Maryam; Jafari, Zahra; Mehrpour, Masoud; Kazemi, Roozbeh; Amiri Shavaki, Younes; Hossienifar, Shamim; Azizi, Mohamad Parsa

    2017-01-01

    Background: The paced auditory serial addition test (PASAT) was primarily developed to assess the effects of traumatic brain injury on cognitive functioning. Working memory (WM) is one of the most important aspects of cognitive function, and WM impairment is one of the clinically remarkable signs of aphasia. To develop the Persian version of PASAT, an initial version was used in individuals with aphasia (IWA). Methods: In this study, 25 individuals with aphasia (29-60 years) and 85 controls (18-60 years) were included. PASAT was presented in the form of recorded 61 single-digit numbers (1 to 9). The participants repeatedly added the 2 recent digits. The psychometric properties of PASAT including convergent validity (using the digit memory span tasks), divergent validity (using results in the control group and IWA group), and face validity were investigated. Test-retest reliability was considered as well. Results: The relationship between the PASAT and digit memory span tests was moderate to strong in the control group (forward digit memory span test: r= 0.52, p< 0.0001; backward digit memory span test: r = 0.48, p< 0.0001). A strong relationship was found in IWA (forward digit memory span test: r= 0.72, p< 0.0001; backward digit memory span test: r= 0.53, p= 0.006). Also, strong testretest reliability (intraclass correlation= 0.95, p< 0.0001) was observed. Conclusion: According to our results, the PASAT is a valid and reliable test to assess working memory, particularly in IWA. It could be used as a feasible tool for clinical and research applications. PMID:29445690

  20. Dissociation between learning and memory impairment and other sickness behaviours during simulated Mycoplasma infection in rats.

    Science.gov (United States)

    Swanepoel, Tanya; Harvey, Brian H; Harden, Lois M; Laburn, Helen P; Mitchell, Duncan

    2011-11-01

    To investigate potential consequences for learning and memory, we have simulated the effects of Mycoplasma infection, in rats, by administering fibroblast-stimulating lipopepide-1 (FSL-1), a pyrogenic moiety of Mycoplasma salivarium. We measured the effects on body temperature, cage activity, food intake, and on spatial learning and memory in a Morris Water Maze. Male Sprague-Dawley rats had radio transponders implanted to measure abdominal temperature and cage activity. After recovery, rats were assigned randomly to receive intraperitoneal (I.P.) injections of FSL-1 (500 or 1000 μg kg(-1) in 1 ml kg(-1) phosphate-buffered saline; PBS) or vehicle (PBS, 1 ml kg(-1)). Body mass and food intake were measured daily. Training in the Maze commenced 18 h after injections and continued daily for four days. Spatial memory was assessed on the fifth day. In other rats, we measured concentrations of brain pro-inflammatory cytokines, interleukin (IL)-1β and IL-6, at 3 and 18 h after injections. FSL-1 administration induced a dose-dependent fever (∼1°C) for two days, lethargy (∼78%) for four days, anorexia (∼65%) for three days and body mass stunting (∼6%) for at least four days. Eighteen hours after FSL-1 administration, when concentrations of IL-1β, but not that of IL-6, were elevated in both the hypothalamus and the hippocampus, and when rats were febrile, lethargic and anorexic, learning in the Maze was unaffected. There also was no memory impairment. Our results support emerging evidence that impaired learning and memory is not inevitable during simulated infection. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Visual behaviour of ADHD children during an attention test : An almost forgotten variable

    NARCIS (Netherlands)

    Börger, Norbert; van der Meere, Jaap

    The goal of this study was to examine whether looking away behaviour of ADHD children interferes with their test performance. ADHD and normal children carried out two continuous performance tests (CPTs): one with a regular interstimulus interval (ISI), and the other with an irregular ISI. Children

  2. Electromagnetic radiation and behavioural response of ticks: an experimental test.

    Science.gov (United States)

    Vargová, Blažena; Majláth, Igor; Kurimský, Juraj; Cimbala, Roman; Kosterec, Michal; Tryjanowski, Piotr; Jankowiak, Łukasz; Raši, Tomáš; Majláthová, Viktória

    2018-05-01

    Factors associated with the increased usage of electronic devices, wireless technologies and mobile phones nowadays are present in increasing amounts in our environment. All living organisms are constantly affected by electromagnetic radiation which causes serious environmental pollution. The distribution and density of ticks in natural habitats is influenced by a complex of abiotic and biotic factors. Exposure to radio-frequency electromagnetic field (RF-EMF) constitutes a potential cause altering the presence and distribution of ticks in the environment. Our main objective was to determine the affinity of Dermacentor reticulatus ticks towards RF-EMF exposure. Originally designed and constructed radiation-shielded tube (RST) test was used to test the affinity of ticks under controlled laboratory conditions. All test were performed in an electromagnetic compatibility laboratory in an anechoic chamber. Ticks were irradiated using a Double-Ridged Waveguide Horn Antenna to RF-EMF at 900 and 5000 MHz, 0 MHz was used as control. The RF-EMF exposure to 900 MHz induced a higher concentration of ticks on irradiated arm of RST as opposed to the RF-EMF at 5000 MHz, which caused an escape of ticks to the shielded arm. This study represents the first experimental evidence of RF-EMF preference in D. reticulatus. The projection of obtained results to the natural environment could help assess the risk of tick borne diseases and could be a tool of preventive medicine.

  3. Spatial recognition test: A novel cognition task for assessing topographical memory in mice.

    Science.gov (United States)

    Havolli, Enes; Hill, Mark Dw; Godley, Annie; Goetghebeur, Pascal Jd

    2017-06-01

    Dysfunction in topographical memory is a core feature of several neurological disorders. There is a large unmet medical need to address learning and memory deficits as a whole in central nervous system disease. There are considerable efforts to identify pro-cognitive compounds but current methods are either lengthy or labour intensive. Our test used a two chamber apparatus and is based on the preference of rodents to explore novel environments. It was used firstly to assess topographical memory in mice at different retention intervals (RI) and secondly to investigate the effect of three drugs reported to be beneficial for cognitive decline associated with Alzheimer's disease, namely: donepezil, memantine and levetiracetam. Animals show good memory performance at all RIs tested under four hours. At the four-hour RI, animals show a significantly poorer memory performance which can be rescued using donepezil, memantine and levetiracetam. Using this test we established and validated a spatial recognition paradigm to address topographical memory in mice by showing a decremental time-induced forgetting response and reversing this decrease in performance using pharmacological tools. The spatial recognition test differs from more commonly used visuospatial laboratory tests in both throughput capability and potentially neuroanatomical substrate. This test has the potential to be used to assess cognitive performance in transgenic animals, disease models and to screen putative cognitive enhancers or depressors.

  4. Effects of chewing gum on mood, learning, memory and performance of an intelligence test.

    Science.gov (United States)

    Smith, Andrew

    2009-04-01

    Recent research suggests that chewing gum may increase alertness and lead to changes in cognitive performance. The present study examined effects of chewing gum on these functions within the context of a single study. This study had four main aims. The first was to examine whether chewing gum improved learning and memory of information in a story. The second aim was to determine whether chewing gum improved test performance on a validated intellectual task (the Alice Heim task). A third aim was to determine whether chewing gum improved performance on short memory tasks (immediate and delayed recall of a list of words, delayed recognition memory, retrieval from semantic memory, and a working memory task). The final aim was to determine whether chewing gum improved mood (alertness, calm and hedonic tone). A cross-over design was used with gum and no-gum sessions being on consecutive weeks. In each week, volunteers attended for two sessions, two days apart. The first session assessed mood, immediate recall of information from a story and performance on short memory tasks. The second session assessed mood, delayed recall of information from a story and performance of an intelligence test (the Alice Heim test). There were no significant effects of chewing gum on any aspect of recall of the story. Chewing gum improved the accuracy of performing the Alice Heim test which confirms the benefits of gum on test performance seen in an earlier study. Chewing gum had no significant effect on the short memory tasks. Chewing gum increased alertness at the end of the test session in both parts of the study. This effect was in the region of a 10% increase and was highly significant (P increases alertness. In contrast, no significant effects of chewing gum were observed in the memory tasks. Intellectual performance was improved in the gum condition. Overall, the results suggest further research on the alerting effects of chewing gum and possible improved test performance in these

  5. Adult age differences in perceptually based, but not conceptually based implicit tests of memory.

    Science.gov (United States)

    Small, B J; Hultsch, D F; Masson, M E

    1995-05-01

    Implicit tests of memory assess the influence of recent experience without requiring awareness of remembering. Evidence concerning age differences on implicit tests of memory suggests small age differences in favor of younger adults. However, the majority of research examining this issue has relied upon perceptually based implicit tests. Recently, a second type of implicit test, one that relies upon conceptually based processes, has been identified. The pattern of age differences on this second type of implicit test is less clear. In the present study, we examined the pattern of age differences on one conceptually based (fact completion) and one perceptually based (stem completion) implicit test of memory, as well as two explicit tests of memory (fact and word recall). Tasks were administered to 403 adults from three age groups (19-34 years, 58-73 years, 74-89 years). Significant age differences in favor of the young were found on stem completion but not fact completion. Age differences were present for both word and fast recall. Correlational analyses examining the relationship of memory performance to other cognitive variables indicated that the implicit tests were supported by different components than the explicit tests, as well as being different from each other.

  6. Enrichment in the Sucker and Weaner Phase Altered the Performance of Pigs in Three Behavioural Tests.

    Science.gov (United States)

    Ralph, Cameron; Hebart, Michelle; Cronin, Greg M

    2018-05-14

    We tested the hypothesis that provision of enrichment in the form of enrichment blocks during the sucker and weaner phases would affect the behaviour of pigs. We measured the performance of pigs in an open field/novel object test, a maze test, an executive function test and the cortisol response of the pigs after exposure to an open field test. The provision of enrichment blocks altered the behaviour of the pigs in all three tests and these changes suggest an increased willingness to explore and possibly an increased ability to learn. The behavioural tests highlighted that young pigs have the capacity to learn complex tasks. Our findings support the notion that the benefits of enrichment cannot be evaluated by measuring the interactions the animal has with the enrichments in the home pen and it may simply be beneficial to live in a more complex environment. We have highlighted that the early rearing environment is important and that the management and husbandry at an early age can have long-term implications for pigs. The enrichment we used in this study was very simple, an enrichment block, and we provide evidence suggesting the provision of enrichment effected pig behavioural responses. Even the simplest of enrichments may have benefits for the welfare and development of young pigs and there is merit in developing enrichment devices that are suitable for use in pig production.

  7. Behavioural analysis of four mouse strains in an anxiety test battery.

    Science.gov (United States)

    van Gaalen, M M; Steckler, T

    2000-10-01

    Differences in locomotor activity, exploratory activity and anxiety-like behaviour of C57BL/6ChR,C57BL/6J, Swiss Webster/J and A/J strain were investigated in an anxiety battery. The battery consisted of paradigms studying spontaneous behaviour after a mild stressor, tasks of innate anxiety (light-dark box, elevated plus maze, novel object exploration), response to a conflict situation (Vogel conflict), conditioned fear and response to inescapable swim stress. Locomotor activity was studied in an open field and compared with locomotion in the other tests. Exploratory behaviour was studied in a 16-hole board task. The data confirm previous studies suggesting that A/J mice are a relatively anxious strain. Also, the data indicated that locomotor activity was independent of the paradigm employed, while the rank order of strain-dependent effects on anxiety-related behaviour changed as a function of the task under study. Our data provide further support for the notion that choice of strain is essential in studies of anxiety-related behaviour. Influence of strain should be considered in pharmacological and lesion studies, as well as in studies with mutant mice. In addition, the data indicate that different anxiety paradigms tax different aspects of anxiety, suggesting that a battery of different tests should be used in studies of anxiety-related behaviour.

  8. Tests to determine water uptake behaviour of tunnel backfill

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, David (Atomic Energy of Canada Limited (AECL) (Canada)); Anttila, S.; Viitanen, M. (Poeyry InfRa Oy (Finland)); Keto, Paula (Saanio and Riekkola Oy, Helsinki (Finland))

    2008-12-15

    A series of 27 large-scale tests have been completed at the 420 level of SKB's Aespoe Hard Rock Laboratory. These tests have examined the influence of natural Aespoe fracture zone water on the movement of water into and through assemblies of Friedland clay blocks and bentonite pellets/ granules. These tests have established the manner in which groundwater may influence backfill and backfilling operations at the repository-scale. Tests have established that it is critical to provide a clay block backfilling system with lateral support and confinement as quickly as possible following block installation. Exposure of the blocks to even low rates of water ingress can result in rapid loss of block cohesion and subsequent slumping of the block materials into the spaces between the blocks and the tunnel walls. Installation of granular or pelletized bentonite clay between the blocks and the walls resulted in a system that was generally stable and not prone to unacceptable short-term strains as water entered. Inflow of water into a backfilled volume does not result in uniform wetting of the pellet/granule filled volume and as a result there is the potential for rapid movement of water from the point(s) of ingress to the downstream face of the backfill. Depending on the inflow rate and flow path(s) developed this flow can be via discrete flow channels that are essentially non-erosive or else they can develop highly erosive flow paths through the clay block materials. Erosion generally tends to be highest in the period immediately following first water exit from the backfill and then decreases as preferential flow paths develop to channel the water directly through the backfill, bypassing large volumes of unsaturated backfill. At the scale examined in this study inflow rates of 0.1 l/min or less do not tend to be immediately problematic when the source is 0.6 m distant from the downstream face of the backfill. At larger scales or longer distances from the working face, it

  9. Tests to determine water uptake behaviour of tunnel backfill

    International Nuclear Information System (INIS)

    Dixon, David; Anttila, S.; Viitanen, M.; Keto, Paula

    2008-12-01

    A series of 27 large-scale tests have been completed at the 420 level of SKB's Aespoe Hard Rock Laboratory. These tests have examined the influence of natural Aespoe fracture zone water on the movement of water into and through assemblies of Friedland clay blocks and bentonite pellets/ granules. These tests have established the manner in which groundwater may influence backfill and backfilling operations at the repository-scale. Tests have established that it is critical to provide a clay block backfilling system with lateral support and confinement as quickly as possible following block installation. Exposure of the blocks to even low rates of water ingress can result in rapid loss of block cohesion and subsequent slumping of the block materials into the spaces between the blocks and the tunnel walls. Installation of granular or pelletized bentonite clay between the blocks and the walls resulted in a system that was generally stable and not prone to unacceptable short-term strains as water entered. Inflow of water into a backfilled volume does not result in uniform wetting of the pellet/granule filled volume and as a result there is the potential for rapid movement of water from the point(s) of ingress to the downstream face of the backfill. Depending on the inflow rate and flow path(s) developed this flow can be via discrete flow channels that are essentially non-erosive or else they can develop highly erosive flow paths through the clay block materials. Erosion generally tends to be highest in the period immediately following first water exit from the backfill and then decreases as preferential flow paths develop to channel the water directly through the backfill, bypassing large volumes of unsaturated backfill. At the scale examined in this study inflow rates of 0.1 l/min or less do not tend to be immediately problematic when the source is 0.6 m distant from the downstream face of the backfill. At larger scales or longer distances from the working face, it is

  10. The 5-HT(4) receptor levels in hippocampus correlates inversely with memory test performance in humans

    DEFF Research Database (Denmark)

    Haahr, Mette Ewers; Fisher, Patrick; Holst, Klaus Kähler

    2013-01-01

    The cerebral serotonin (5-HT) system is involved in cognitive functions such as memory and learning and animal studies have repeatedly shown that stimulation of the 5-HT type 4 receptor (5-HT(4) R) facilitates memory and learning and further that the 5-HT(4) R modulates cellular memory processes...... in hippocampus. However, any associations between memory functions and the expression of the 5-HT(4) R in the human hippocampus have not been investigated. Using positron emission tomography with the tracer [(11) C]SB207145 and Reys Auditory Verbal Learning Test we aimed to examine the individual variation...... of the 5-HT4R binding in hippocampus in relation to memory acquisition and consolidation in healthy young volunteers. We found significant, negative associations between the immediate recall scores and left and right hippocampal BP(ND) , (p = 0.009 and p = 0.010 respectively) and between the right...

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

    OpenAIRE

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

    2007-01-01

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

  12. Exploratory behaviour in the open field test adapted for larval zebrafish: impact of environmental complexity.

    Science.gov (United States)

    Ahmad, Farooq; Richardson, Michael K

    2013-01-01

    This study aimed to develop and characterize a novel (standard) open field test adapted for larval zebrafish. We also developed and characterized a variant of the same assay consisting of a colour-enriched open field; this was used to assess the impact of environmental complexity on patterns of exploratory behaviours as well to determine natural colour preference/avoidance. We report the following main findings: (1) zebrafish larvae display characteristic patterns of exploratory behaviours in the standard open field, such as thigmotaxis/centre avoidance; (2) environmental complexity (i.e. presence of colours) differentially affects patterns of exploratory behaviours and greatly attenuates natural zone preference; (3) larvae displayed the ability to discriminate colours. As reported previously in adult zebrafish, larvae showed avoidance towards blue and black; however, in contrast to the reported adult behaviour, larvae displayed avoidance towards red. Avoidance towards yellow and preference for green and orange are shown for the first time, (4) compared to standard open field tests, exposure to the colour-enriched open field resulted in an enhanced expression of anxiety-like behaviours. To conclude, we not only developed and adapted a traditional rodent behavioural assay that serves as a gold standard in preclinical drug screening, but we also provide a version of the same test that affords the possibility to investigate the impact of environmental stress on behaviour in larval zebrafish while representing the first test for assessment of natural colour preference/avoidance in larval zebrafish. In the future, these assays will improve preclinical drug screening methodologies towards the goal to uncover novel drugs. This article is part of a Special Issue entitled: insert SI title. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. MWCNTs-Reinforced Epoxidized Linseed Oil Plasticized Polylactic Acid Nanocomposite and Its Electroactive Shape Memory Behaviour

    OpenAIRE

    Alam, Javed; Alam, Manawwer; Raja, Mohan; Abduljaleel, Zainularifeen; Dass, Lawrence

    2014-01-01

    A novel electroactive shape memory polymer nanocomposite of epoxidized linseed oil plasticized polylactic acid and multi-walled carbon nanotubes (MWCNTs) was prepared by a combination of solution blending, solvent cast technique, and hydraulic hot press moulding. In this study, polylactic acid (PLA) was first plasticized by epoxidized linseed oil (ELO) in order to overcome the major limitations of PLA, such as high brittleness, low toughness, and low tensile elongation. Then, MWCNTs were inc...

  14. Do Different Tests of Episodic Memory Produce Consistent Results in Human Adults?

    Science.gov (United States)

    Cheke, Lucy G.; Clayton, Nicola S.

    2013-01-01

    A number of different philosophical, theoretical, and empirical perspectives on episodic memory have led to the development of very different tests with which to assess it. Although these tests putatively assess the same psychological capacity, they have rarely been directly compared. Here, a sample of undergraduates was tested on three different…

  15. Test-Enhanced Learning of Natural Concepts: Effects on Recognition Memory, Classification, and Metacognition

    Science.gov (United States)

    Jacoby, Larry L.; Wahlheim, Christopher N.; Coane, Jennifer H.

    2010-01-01

    Three experiments examined testing effects on learning of natural concepts and metacognitive assessments of such learning. Results revealed that testing enhanced recognition memory and classification accuracy for studied and novel exemplars of bird families on immediate and delayed tests. These effects depended on the balance of study and test…

  16. Stress recovery and cyclic behaviour of an Fe-Mn-Si shape memory alloy after multiple thermal activation

    Science.gov (United States)

    Hosseini, E.; Ghafoori, E.; Leinenbach, C.; Motavalli, M.; Holdsworth, S. R.

    2018-02-01

    The stress recovery and cyclic deformation behaviour of Fe-17Mn-5Si-10Cr-4Ni-1(V,C) shape memory alloy (Fe-SMA) strips, which are often used for pre-stressed strengthening of structural members, were studied. The evolution of recovery stress under different constraint conditions was studied. The results showed that the magnitude of the tensile stress in the Fe-SMA member during thermal activation can have a signification effect on the final recovery stress. The higher the tensile load in the Fe-SMA (e.g., caused by dead load or thermal expansion of parent structure during heating phase), the lower the final recovery stress. Furthermore, this study investigated the cyclic behaviour of the activated SMA followed by a second thermal activation. Although the magnitude of the recovery stress decreased during the cyclic loading, the second thermal activation could retrieve a significant part of the relaxed recovery stress. This observation suggests that the relaxation of recovery stress during cyclic loading is due to a reversible phase transformation-induced deformation (i.e., forward austenite-to-martensite transformation) rather than an irreversible dislocation-induced plasticity. Retrieval of the relaxed recovery stress by the reactivation process has important practical implications as the prestressing loss in pre-stressed civil structures can be simply recovered by reheating of the Fe-SMA elements.

  17. Effects of repeated asenapine in a battery of tests for anxiety-like behaviours in mice.

    Science.gov (United States)

    Ene, Hila M; Kara, Nirit Z; Barak, Noa; Reshef Ben-Mordechai, Tal; Einat, Haim

    2016-04-01

    A number of atypical antipsychotic drugs were demonstrated to have anxiolytic effects in patients and in animal models. These effects were mostly suggested to be the consequence of the drugs' affinity to the serotonin system and its receptors. Asenapine is a relatively new atypical antipsychotic that is prescribed for schizophrenia and for bipolar mania. Asenapine has a broad pharmacological profile with significant effects on serotonergic receptors, hence it is reasonable to expect that asenapine may have some anxiolytic effects. The present study was therefore designed to examine possible effects of asenapine on anxiety-like behaviour of mice. Male ICR mice were repeatedly treated with 0.1 or 0.3 mg/kg injections of asenapine and then tested in a battery of behavioural tests related to anxiety including the open-field test, elevated plus-maze (EPM), defensive marble burying and hyponeophagia tests. In an adjunct experiment, we tested the effects of acute diazepam in the same test battery. The results show that diazepam reduced anxiety-like behaviour in the EPM, the defensive marble burying test and the hyponeophagia test but not in the open field. Asenapine has anxiolytic-like effects in the EPM and the defensive marble burying tests but had no effects in the open-field or the hyponeophagia tests. Asenapine had no effects on locomotor activity. The results suggest that asenapine may have anxiolytic-like properties and recommends that clinical trials examining such effects should be performed.

  18. Testing the Limits of Skill Transfer for Scrabble Experts in Behaviour and Brain

    Directory of Open Access Journals (Sweden)

    Sophia Van Hees

    2016-11-01

    Full Text Available We investigated transfer of the skills developed by competitive Scrabble players. Previous studies reported superior performance for Scrabble experts on the lexical decision task (LDT, suggesting near transfer of Scrabble skills. Here we investigated the potential for far transfer to a symbol decision task (SDT; in particular, transfer of enhanced long-term working memory for vertically presented stimuli. Our behavioural results showed no evidence for far transfer. Despite years of intensive practice, Scrabble experts were no faster and no more accurate than controls in the SDT. However, our fMRI and EEG data from the SDT suggest that the neural repertoire that Scrabble experts develop supports task performance even outside of the practised domain, in a non-linguistic context. The regions engaged during the SDT were different across groups: controls engaged temporal-frontal regions, whereas Scrabble experts engaged posterior visual and temporal-parietal regions. In Scrabble experts, activity related to Scrabble skill (anagramming scores included regions associated with visual-spatial processing and long-term working memory, and overlapped with regions previously shown to be associated with Scrabble expertise in the near transfer task (LDT. Analysis of source waveforms within these regions showed that participants with higher anagramming scores had larger P300 amplitudes, potentially reflecting greater working memory capacity, or less variability in the participants who perform the task more efficiently. Thus, the neuroimaging results provide evidence of brain transfer in the absence of behavioural transfer, providing new clues about the consequences of long-term training associated with competitive Scrabble expertise.

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

    Science.gov (United States)

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

    2016-11-01

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

  20. Modeling learning and memory using verbal learning tests: results from ACTIVE.

    Science.gov (United States)

    Gross, Alden L; Rebok, George W; Brandt, Jason; Tommet, Doug; Marsiske, Michael; Jones, Richard N

    2013-03-01

    To investigate the influence of memory training on initial recall and learning. The Advanced Cognitive Training for Independent and Vital Elderly study of community-dwelling adults older than age 65 (n = 1,401). We decomposed trial-level recall in the Auditory Verbal Learning Test (AVLT) and Hopkins Verbal Learning Test (HVLT) into initial recall and learning across trials using latent growth models. Trial-level increases in words recalled in the AVLT and HVLT at each follow-up visit followed an approximately logarithmic shape. Over the 5-year study period, memory training was associated with slower decline in Trial 1 AVLT recall (Cohen's d = 0.35, p = .03) and steep pre- and posttraining acceleration in learning (d = 1.56, p learning, d = 3.10, p memory-trained group had a higher level of recall than the control group through the end of the 5-year study period despite faster decline in learning. This study contributes to the understanding of the mechanisms by which training benefits memory and expands current knowledge by reporting long-term changes in initial recall and learning, as measured from growth models and by characterization of the impact of memory training on these components. Results reveal that memory training delays the worsening of memory span and boosts learning.

  1. Behaviour Test with the Leaching of a Waste package

    International Nuclear Information System (INIS)

    Fischer, G.R

    1999-01-01

    The radioactive wastes are classified, in low, intermediate and high level wastes, according to the characteristics of the radionuclides in, its specific activity and half-life.Those are the three parameters that indicate how long the radioactive waste will be keep confined, in safe conditions before its contaminants go into the environment or before the institutional controls on the final disposal installations are removed.The confinement time can be estimated in ten half-lives, because since that moment its activity has decayed at one thousandth from the original .In low level wastes the confinement periods are nearly fifty years while in intermediate level, the periods can be until three hundreds years.These times are normally controlled by government institutions that are in charge of looking after people about the no-liberation of toxic elements at the environment.Therefore the wastes can be confined in a motionless matrix so that they can be placed in shallow land burials.On the other hand, the high level wastes which confinement times are estimated in ten or so thousand years, must be disposed in deep underground geological repositories.Obviously, there are no state controls for them.There are several matrices or different ways of stabilizing a waste, that will be introduced in this essay.It is also important to take account into the factors that degrade those matrices and speed up the released time of the radionuclides into the environment.There have been analyzed too, the radionuclides transport process that go through the matrix and the factors that affect the aforesaid process.Moreover, the diffusion was studied in a such detailed way, assuming that it is the most important mass transport process, in agreement with other studies made before.The leach rates and the diffusion coefficients have been calculated and determinated by means of measurements in a full scale leaching test.Those coefficients were compared with small-scale laboratory and

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

    Science.gov (United States)

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

    2004-05-01

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

  3. Attitudes and exercise adherence: test of the Theories of Reasoned Action and Planned Behaviour.

    Science.gov (United States)

    Smith, R A; Biddle, S J

    1999-04-01

    Three studies of exercise adherence and attitudes are reported that tested the Theory of Reasoned Action and the Theory of Planned Behaviour. In a prospective study of adherence to a private fitness club, structural equation modelling path analysis showed that attitudinal and social normative components of the Theory of Reasoned Action accounted for 13.1% of the variance in adherence 4 months later, although only social norm significantly predicted intention. In a second study, the Theory of Planned Behaviour was used to predict both physical activity and sedentary behaviour. Path analyses showed that attitude and perceived control, but not social norm, predicted total physical activity. Physical activity was predicted from intentions and control over sedentary behaviour. Finally, an intervention study with previously sedentary adults showed that intentions to be active measured at the start and end of a 10-week intervention were associated with the planned behaviour variables. A multivariate analysis of variance revealed no significant multivariate effects for time on the planned behaviour variables measured before and after intervention. Qualitative data provided evidence that participants had a positive experience on the intervention programme and supported the role of social normative factors in the adherence process.

  4. Free recall test experience potentiates strategy-driven effects of value on memory.

    Science.gov (United States)

    Cohen, Michael S; Rissman, Jesse; Hovhannisyan, Mariam; Castel, Alan D; Knowlton, Barbara J

    2017-10-01

    People tend to show better memory for information that is deemed valuable or important. By one mechanism, individuals selectively engage deeper, semantic encoding strategies for high value items (Cohen, Rissman, Suthana, Castel, & Knowlton, 2014). By another mechanism, information paired with value or reward is automatically strengthened in memory via dopaminergic projections from midbrain to hippocampus (Shohamy & Adcock, 2010). We hypothesized that the latter mechanism would primarily enhance recollection-based memory, while the former mechanism would strengthen both recollection and familiarity. We also hypothesized that providing interspersed tests during study is a key to encouraging selective engagement of strategies. To test these hypotheses, we presented participants with sets of words, and each word was associated with a high or low point value. In some experiments, free recall tests were given after each list. In all experiments, a recognition test was administered 5 minutes after the final word list. Process dissociation was accomplished via remember/know judgments at recognition, a recall test probing both item memory and memory for a contextual detail (word plurality), and a task dissociation combining a recognition test for plurality (intended to probe recollection) with a speeded item recognition test (to probe familiarity). When recall tests were administered after study lists, high value strengthened both recollection and familiarity. When memory was not tested after each study list, but rather only at the end, value increased recollection but not familiarity. These dual process dissociations suggest that interspersed recall tests guide learners' use of metacognitive control to selectively apply effective encoding strategies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Memory

    OpenAIRE

    Wager, Nadia

    2017-01-01

    This chapter will explore a response to traumatic victimisation which has divided the opinions of psychologists at an exponential rate. We will be examining amnesia for memories of childhood sexual abuse and the potential to recover these memories in adulthood. Whilst this phenomenon is generally accepted in clinical circles, it is seen as highly contentious amongst research psychologists, particularly experimental cognitive psychologists. The chapter will begin with a real case study of a wo...

  6. The design and testing of a memory metal actuated boom release mechanism

    Science.gov (United States)

    Powley, D. G.; Brook, G. B.

    1979-01-01

    A boom latch and release mechanism was designed, manufactured and tested, based on a specification for the ISEE-B satellite mechanism. From experimental results obtained, it is possible to calculate the energy available and the operating torques which can be achieved from a torsional shape memory element in terms of the reversible strain induced by prior working. Some guidelines to be followed when designing mechanisms actuated by shape memory elements are included.

  7. Dual long memory of inflation and test of the relationship between inflation and inflation uncertainty

    OpenAIRE

    LIU Jinquan; ZHENG Tingguo; SUI Jianli

    2008-01-01

    This paper uses the ARFIMA-FIGARCH model to investigate the China¡¯s monthly inflation rate from January 1983 to October 2005. It is found that both first moment and second moment of inflation have remarkable long memory, indicating the existence of long memory properties in both inflation level and inflation uncertainty. By the Granger-causality test on inflation rate and inflation uncertainty, it is shown that the inflation level affects the inflation uncertainty and so supports Friedman hy...

  8. The Object Context-place-location Paradigm for Testing Spatial Memory in Mice.

    Science.gov (United States)

    Lesburguères, Edith; Tsokas, Panayiotis; Sacktor, Todd Charlton; Fenton, André Antonio

    2017-04-20

    This protocol was originally designed to examine long-term spatial memory in PKMζ knockout ( i.e ., PKMζ-null) mice (Tsokas et al ., 2016). Our main goal was to test whether the ability of these animals to maintain previously acquired spatial information was sensitive to the type and complexity of the spatial information that needs to be remembered. Accordingly, we modified and combined into a single protocol, three novelty-preference tests, specifically the object-in-context, object-in-place and object-in-location tests, adapted from previous studies in rodents (Mumby et al ., 2002; Langston and Wood, 2010; Barker and Warburton, 2011). During the training (learning) phase of the procedure, mice are repeatedly exposed to three different environments in which they learn the spatial arrangement of an environment-specific set of non-identical objects. After this learning phase is completed, each mouse receives three different memory tests configured as environment mismatches, in which the previously learned objects-in-space configurations have been modified from the original training situation. The mismatch tests differ in their cognitive demands due to the type of spatial association that is manipulated, specifically evaluating memory for object-context and object-place associations. During each memory test, the time differential spent exploring the novel (misplaced) and familiar objects is computed as an index of novelty discrimination. This index is the behavioral measure of memory recall of the previously acquired spatial associations.

  9. Dichotic assessment of verbal memory function: development and validation of the Persian version of Dichotic Verbal Memory Test.

    Science.gov (United States)

    Aghamollaei, Maryam; Jafari, Zahra; Tahaei, Aliakbar; Toufan, Reyhane; Keyhani, Mohammadreza; Rahimzade, Shadi; Esmaeili, Mahdieh

    2013-09-01

    The Dichotic Verbal Memory Test (DVMT) is useful in detecting verbal memory deficits and differences in memory function between the brain hemispheres. The purpose of this study was to prepare the Persian version of DVMT, to obtain its results in 18- to 25-yr-old Iranian individuals, and to examine the ear, gender, and serial position effect. The Persian version of DVMT consisted of 18 10-word lists. After preparing the 18 lists, content validity was assessed by a panel of eight experts and the equivalency of the lists was evaluated. Then the words were recorded on CD in a dichotic mode such that 10 words were presented to one ear, with the same words reversed simultaneously presented to the other ear. Thereafter, it was performed on a sample of young, normal, Iranian individuals. Thirty normal individuals (no history of neurological, ontological, or psychological diseases) with ages ranging from 18 to 25 yr were examined for evaluating the equivalency of the lists, and 110 subjects within the same age range participated in the final stage of the study to obtain the normative data on the developed test. There was no significant difference between the mean scores of the 18 developed lists (p > 0.05). The mean content validity index (CVI) score was .96. A significant difference was found between the mean score of the two ears (p < 0.05) and between female and male participants (p < 0.05). The Persian version of DVMT has good content validity and can be used for verbal memory assessment in Iranian young adults. American Academy of Audiology.

  10. The role of novelty detection in food memory

    NARCIS (Netherlands)

    Morin-Audebrand, L.; Mojet, J.; Chabanet, C.; Issanchou, S.; Moeller, P.; Koester, E.; Sulmont-Rossé, C.

    2012-01-01

    Memory plays a central role in food choice. Recent studies focusing on food memory in everyday eating and drinking behaviour used a paradigm based on incidental learning of target foods and unexpected memory testing, demanding recognition of the target among distractors, which deviate slightly from

  11. Influence of memory, attention, IQ and age on auditory temporal processing tests: preliminary study.

    Science.gov (United States)

    Murphy, Cristina Ferraz Borges; Zachi, Elaine Cristina; Roque, Daniela Tsubota; Ventura, Dora Selma Fix; Schochat, Eliane

    2014-01-01

    To investigate the existence of correlations between the performance of children in auditory temporal tests (Frequency Pattern and Gaps in Noise--GIN) and IQ, attention, memory and age measurements. Fifteen typically developing individuals between the ages of 7 to 12 years and normal hearing participated in the study. Auditory temporal processing tests (GIN and Frequency Pattern), as well as a Memory test (Digit Span), Attention tests (auditory and visual modality) and intelligence tests (RAVEN test of Progressive Matrices) were applied. Significant and positive correlation between the Frequency Pattern test and age variable were found, which was considered good (p<0.01, 75.6%). There were no significant correlations between the GIN test and the variables tested. Auditory temporal skills seem to be influenced by different factors: while the performance in temporal ordering skill seems to be influenced by maturational processes, the performance in temporal resolution was not influenced by any of the aspects investigated.

  12. Polypropylene-rubber blends b 3: the effect of test speed on the fracture behaviour

    NARCIS (Netherlands)

    van der Wal, A.; Wal, A.; Gaymans, R.J.

    1999-01-01

    Polypropylene–EPDM blends were prepared on a twin screw extruder with a rubber content 0–40 vol%. On these materials the yield strength and the notched tensile behaviour was studied as function of test speed (10−4–10 m/s). With an infrared temperature camera the heat development in the notched

  13. .i.Aspergillus viridinutans./i. complex: polyphasic taxonomy, mating behaviour and antifungal susceptibility testing

    Czech Academy of Sciences Publication Activity Database

    Dudová, Z.; Hubka, V.; Svobodová, L.; Hamal, P.; Nováková, Alena; Matsuzawa, T.; Yaguchi, T.; Kubátová, A.; Kolařík, Miroslav

    2013-01-01

    Roč. 56, Suppl. 3 (2013), s. 162-163 ISSN 0933-7407. [Trends in Medical Mycology /6./. 11.10.2013-14.10.2013, Copenhagen] Institutional support: RVO:60077344 ; RVO:61388971 Keywords : Aspergillus viridinutans * polyphasic taxonomy * mating behaviour * antifungal susceptibility testing Subject RIV: EE - Microbiology, Virology

  14. Social and Behavioural Correlates of HIV Testing Among Australian Gay and Bisexual Men in Regular Relationships

    NARCIS (Netherlands)

    Lee, Evelyn; Murphy, Dean; Mao, Limin; de Wit, John; Prestage, Garrett; Zablotska, Iryna; Holt, Martin

    In this study we sought to identify the social and behavioural characteristics of Australian gay and bisexual men who had and had not tested for HIV during their current relationship. The results were based on 2012 and 2013 data collected from ongoing cross-sectional and community-based surveys held

  15. Experimental test of host specificity in a behaviour-modifying trematode

    DEFF Research Database (Denmark)

    Hernandez, R.N.; Fredensborg, Brian Lund

    2015-01-01

    Host behavioural modification by parasites is a common and well-documented phenomenon. However, knowledge on the complexity and specificity of the underlying mechanisms is limited, and host specificity among manipulating parasites has rarely been experimentally verified. We tested the hypothesis...

  16. Wedge Splitting Test on Fracture Behaviour of Fiber Reinforced and Regular High Performance Concretes

    DEFF Research Database (Denmark)

    Hodicky, Kamil; Hulin, Thomas; Schmidt, Jacob Wittrup

    2013-01-01

    The fracture behaviour of three fiber reinforced and regular High Performance Concretes (HPC) is presented in this paper. Two mixes are based on optimization of HPC whereas the third mix was a commercial mix developed by CONTEC ApS (Denmark). The wedge splitting test setup with 48 cubical specimens...

  17. Effects of caffeine on learning and memory in rats tested in the Morris water maze

    Directory of Open Access Journals (Sweden)

    Angelucci M.E.M.

    2002-01-01

    Full Text Available We studied some of the characteristics of the improving effect of the non-specific adenosine receptor antagonist, caffeine, using an animal model of learning and memory. Groups of 12 adult male Wistar rats receiving caffeine (0.3-30 mg/kg, ip, in 0.1 ml/100 g body weight administered 30 min before training, immediately after training, or 30 min before the test session were tested in the spatial version of the Morris water maze task. Post-training administration of caffeine improved memory retention at the doses of 0.3-10 mg/kg (the rats swam up to 600 cm less to find the platform in the test session, P<=0.05 but not at the dose of 30 mg/kg. Pre-test caffeine administration also caused a small increase in memory retrieval (the escape path of the rats was up to 500 cm shorter, P<=0.05. In contrast, pre-training caffeine administration did not alter the performance of the animals either in the training or in the test session. These data provide evidence that caffeine improves memory retention but not memory acquisition, explaining some discrepancies among reports in the literature.

  18. The effects of emotion regulation on explicit memory depend on strategy and testing method.

    Science.gov (United States)

    Knight, Marisa; Ponzio, Allison

    2013-12-01

    Although previous work has shown that emotion regulation strategies can influence memory, the mechanisms through which different strategies produce different memory outcomes are not well understood. We examined how two cognitive reappraisal strategies with similar elaboration demands but diverging effects on visual attention and emotional arousal influenced explicit memory for emotional stimuli and for the strategies used to evaluate the stimuli. At encoding, participants used reappraisal to increase and decrease the personal relevance of neutral and emotional pictures. In two experiments, recall accuracy was highest for emotional pictures featured on increase trials, intermediate for emotional pictures featured on look (respond naturally) trials, and lowest for emotional pictures featured on decrease trials. This recall pattern emerged after a short delay (15 min) and persisted over a longer delay (48 hr). Memory accuracy for the strategies used to evaluate the pictures showed a different pattern: Strategy memory was better for emotional pictures featured on decrease and increase trials than for pictures featured on look trials. Our findings show that the effects of emotion regulation on memory depend both on the particular strategy engaged and the particular aspect of memory being tested.

  19. Testing for long memory in volatility in the Indian Forex market

    Directory of Open Access Journals (Sweden)

    Kumar Anoop S.

    2014-01-01

    Full Text Available This article attempts to verify the presence of long memory in volatility in the Indian foreign exchange market using daily bilateral returns of the Indian Rupee against the US dollar from 17/02/1994 to 08/11/2013. In the first part of the analysis the presence of long-term dependence is confirmed in the return series as well as in two measures of unconditional volatility (absolute returns and squared returns by employing three measures of long memory. Next, the presence of long memory in conditional volatility is tested using ARMA-FIGARCH and ARMA-FIAPARCH models under various distributional assumptions. The results confirm the presence of long memory in conditional variance for two models. In the last part, the presence of long memory in conditional mean and conditional variance is verified using ARFIMA-FIGARCH and ARFIMA-FIAPARCH models. It is also found that long-memory models fare well compared to short-memory models in sample forecast performance.

  20. A fully automated Drosophila olfactory classical conditioning and testing system for behavioral learning and memory assessment.

    Science.gov (United States)

    Jiang, Hui; Hanna, Eriny; Gatto, Cheryl L; Page, Terry L; Bhuva, Bharat; Broadie, Kendal

    2016-03-01

    Aversive olfactory classical conditioning has been the standard method to assess Drosophila learning and memory behavior for decades, yet training and testing are conducted manually under exceedingly labor-intensive conditions. To overcome this severe limitation, a fully automated, inexpensive system has been developed, which allows accurate and efficient Pavlovian associative learning/memory analyses for high-throughput pharmacological and genetic studies. The automated system employs a linear actuator coupled to an odorant T-maze with airflow-mediated transfer of animals between training and testing stages. Odorant, airflow and electrical shock delivery are automatically administered and monitored during training trials. Control software allows operator-input variables to define parameters of Drosophila learning, short-term memory and long-term memory assays. The approach allows accurate learning/memory determinations with operational fail-safes. Automated learning indices (immediately post-training) and memory indices (after 24h) are comparable to traditional manual experiments, while minimizing experimenter involvement. The automated system provides vast improvements over labor-intensive manual approaches with no experimenter involvement required during either training or testing phases. It provides quality control tracking of airflow rates, odorant delivery and electrical shock treatments, and an expanded platform for high-throughput studies of combinational drug tests and genetic screens. The design uses inexpensive hardware and software for a total cost of ∼$500US, making it affordable to a wide range of investigators. This study demonstrates the design, construction and testing of a fully automated Drosophila olfactory classical association apparatus to provide low-labor, high-fidelity, quality-monitored, high-throughput and inexpensive learning and memory behavioral assays. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Space Qualification Testing of a Shape Memory Alloy Deployable CubeSat Antenna

    Science.gov (United States)

    2016-09-15

    from a specific input vibration . This excitation vibration can be applied acoustically through a speaker or physically by an impact hammer. NASA...Shape Memory Alloy (SMA) L-band deployable QHA. In this research, a testing approach is developed to conduct random vibration , thermal vacuum...92 4.4 Vibration Test Results

  2. Reduced Interference from Memory Testing: A Postretrieval Monitoring Account

    Science.gov (United States)

    Pierce, Benton H.; Gallo, David A.; McCain, Jason L.

    2017-01-01

    Initial learning can interfere with subsequent learning (proactive interference [PI]), but recent work indicates initial testing can reduce PI. Here, we tested 2 alternative hypotheses of this effect: Does testing reduce PI by constraining retrieval to the target list, or by facilitating a postretrieval monitoring process? Participants first…

  3. Shape memory behaviour of radiation-crosslinked PCL/PMVS blends

    International Nuclear Information System (INIS)

    Zhu Guangming; Xu Shuogui; Wang Jinhua; Zhang Longbin

    2006-01-01

    The performance and radiation crosslinking of polycaprolactone (PCL) and polymethylvinylsiloxane (PMVS) blends has been investigated. Radiation crosslinking of PCL/PMVS blends followed the Charlesby-Pinner equation, and PMVS promoted the radiation crosslinking of the blends. As the concentration of PMVS increased, the gelation dose and the ratio of degradation to crosslinking (p 0 /q 0 ) decreased and the efficiency of radiation crosslinking increased. The elastic modulus below the melting point of PCL of radiation-crosslinked PCL/PMVS blends decreased with the increase of PMVS, and increased above the melting point. The crosslinked PCL/PMVS blends exhibited excellent shape memory effects, and the ratios of deformation to recovery were more than 95%

  4. Investigation of the ramp testing behaviour of fuel pins with different diameters

    International Nuclear Information System (INIS)

    Pott, G.; Herren, M.; Wigger, B.

    1979-09-01

    The aim of these experiments was the investigation of the influence of different fuel pin diameter on the ramp testing behaviour. Fuel elements with diameter between 10,75 and 15,6 mm and different cladding thickness had been ramptested in the HBWR (Halden Boiling Water Reactor) after preirradiated in the same facility. Fuel pins with the smallest diameter of 10,75 mm failed. This was indicated by fission gas release measurement. Metallographic examination showed these failure were caused by hydride blisters. A systematic influence of fuel pin diameter and cladding thickness on the ramptesting behaviour was not observed. (orig.) [de

  5. Measurement of overgeneral autobiographical memory: Psychometric properties of the autobiographical memory test in young and older populations.

    Science.gov (United States)

    Ros, Laura; Romero, Dulce; Ricarte, Jorge J; Serrano, Juan P; Nieto, Marta; Latorre, Jose M

    2018-01-01

    The Autobiographical Memory Test (AMT) is the most widely used measure of overgeneral autobiographical memory (OGM). The AMT appears to have good psychometric properties, but more research is needed on the influence and applicability of individual cue words in different languages and populations. To date, no studies have evaluated its usefulness as a measure of OMG in Spanish or older populations. This work aims to analyze the applicability of the AMT in young and older Spanish samples. We administered a Spanish version of the AMT to samples of young (N = 520) and older adults (N = 155). We conducted confirmatory factor analysis (CFA), item response theory-based analysis (IRT) and differential item functioning (DIF). Results confirm the one-factor structure for the AMT. IRT analysis suggests that both groups find the AMT easy given that they generally perform well, and that it is more precise in individuals who score low on memory specificity. DIF analysis finds three items differ in their functioning depending on age group. This differential functioning of these items affects the overall AMT scores and, thus, they should be excluded from the AMT in studies comparing young and older samples. We discuss the possible implications of the samples and cue words used.

  6. Modulating influences of memory strength and sensitivity of the retrieval test on the detectability of the sleep consolidation effect.

    Science.gov (United States)

    Schoch, Sarah F; Cordi, Maren J; Rasch, Björn

    2017-11-01

    Emotionality can increase recall probability of memories as emotional information is highly relevant for future adaptive behavior. It has been proposed that memory processes acting during sleep selectively promote the consolidation of emotional memories, so that neutral memories no longer profit from sleep consolidation after learning. This appears as a selective effect of sleep for emotional memories. However, other factors contribute to the appearance of a consolidation benefit and influence this interpretation. Here we show that the strength of the memory trace before sleep and the sensitivity of the retrieval test after sleep are critical factors contributing to the detection of the benefit of sleep on memory for emotional and neutral stimuli. 228 subjects learned emotional and neutral pictures and completed a free recall after a 12-h retention interval of either sleep or wakefulness. We manipulated memory strength by including an immediate retrieval test before the retention interval in half of the participants. In addition, we varied the sensitivity of the retrieval test by including an interference learning task before retrieval testing in half of the participants. We show that a "selective" benefit of sleep for emotional memories only occurs in the condition with high memory strength. Furthermore, this "selective" benefit disappeared when we controlled for the memory strength before the retention interval and used a highly sensitive retrieval test. Our results indicate that although sleep benefits are more robust for emotional memories, neutral memories similarly profit from sleep after learning when more sensitive indicators are used. We conclude that whether sleep benefits on memory appear depends on several factors, including emotion, memory strength and sensitivity of the retrieval test. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Decreased prefrontal functional brain response during memory testing in women with Cushing's syndrome in remission.

    Science.gov (United States)

    Ragnarsson, Oskar; Stomby, Andreas; Dahlqvist, Per; Evang, Johan A; Ryberg, Mats; Olsson, Tommy; Bollerslev, Jens; Nyberg, Lars; Johannsson, Gudmundur

    2017-08-01

    Neurocognitive dysfunction is an important feature of Cushing's syndrome (CS). Our hypothesis was that patients with CS in remission have decreased functional brain responses in the prefrontal cortex and hippocampus during memory testing. In this cross-sectional study we included 19 women previously treated for CS and 19 controls matched for age, gender, and education. The median remission time was 7 (IQR 6-10) years. Brain activity was studied with functional magnetic resonance imaging during episodic- and working-memory tasks. The primary regions of interest were the prefrontal cortex and the hippocampus. A voxel-wise comparison of functional brain responses in patients and controls was performed. During episodic-memory encoding, patients displayed lower functional brain responses in the left and right prefrontal gyrus (pright inferior occipital gyrus (pbrain responses in the left posterior hippocampus in patients (p=0.05). During episodic-memory retrieval, the patients displayed lower functional brain responses in several brain areas with the most predominant difference in the right prefrontal cortex (pbrain response during a more complex working memory task compared with a simpler one. In conclusion, women with CS in long-term remission have reduced functional brain responses during episodic and working memory testing. This observation extends previous findings showing long-term adverse effects of severe hypercortisolaemia on brain function. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Design, fabrication, testing and delivery of a feasibility model laminated ferrite memory

    Science.gov (United States)

    Heckler, H. C.

    1973-01-01

    The effect of using multiword addressing with laminated ferrite arrays was made. Both a reduction in the number of components, and a reduction in power consumption was obtained for memory capacities between one million bits and one million words. An investigation into the effect of variations in the processing steps resulted in a number of process modifications that improved the quality of the arrays. A feasibility model laminated ferrite memory system was constructed by modifying a commercial plated wire memory system to operate with laminated ferrite arrays. To provide flexibility for the testing of the laminated ferrite memory, an exerciser has been constructed to automatically control the loading and recirculation of arbitrary size checkerboard patterns of one's and zero's and to display the patterns of stored information on a CRT screen.

  9. A dedicated system for topographical working memory: evidence from domain-specific interference tests.

    Science.gov (United States)

    Piccardi, L; Nori, R; Boccia, M; Barbetti, S; Verde, P; Guariglia, C; Ferlazzo, F

    2015-08-01

    In the present study, we used single- and dual-task conditions to investigate the nature of topographical working memory to better understand what type of task can hamper performance during navigation. During dual-task conditions, we considered four different sources of interference: motor (M), spatial motor (SM), verbal (i.e. articulatory suppression AS) and spatial environmental (SE). In order to assess the nature of topographical working memory, we used the Walking Corsi Test, asking the participants to perform two tasks simultaneously (M, SM, AS and SE). Our results showed that only spatial-environmental interference hampers the execution of a topographical working memory task, suggesting a task-domain-specific effect. We also found general gender differences in the topographical working memory capabilities: men were more proficient than women, regardless of the type of interferences. However, like men, women performed worse when a spatial-environmental interference was present.

  10. Terrestrial avoidance behaviour tests as screening tool to assess soil contamination

    International Nuclear Information System (INIS)

    Loureiro, Susana; Soares, Amadeu M.V.M.; Nogueira, Antonio J.A.

    2005-01-01

    To assess soil quality and risk assessment, bioassays can be useful tools to gauge the potential toxicity of contaminants focusing on their bioavailable fraction. A rapid and sublethal avoidance behaviour test was used as a screening tool with the earthworm Eisenia andrei and the isopod Porcellionides pruinosus, where organisms were exposed during 48 h to several chemicals (lindane, dimethoate and copper sulphate, for isopods and carbendazim, benomyl, dimethoate and copper sulphate for earthworms). Both species were also exposed to soils from an abandoned mine. For all bioassays a statistical approach was used to derive EC 50 values. Isopods and earthworms were able to perceive the presence of toxic compounds and escaping from contaminated to clean soil. Furthermore the behaviour parameter was equally or more sensitive then other sublethal parameters (e.g. reproduction or growth), expressing the advantages of Avoidance Behaviour Tests as screening tools in ERA. - Avoidance Behaviour Tests with earthworms and isopods can be used as screening tools in the evaluation of soil contamination

  11. Topographical memory analyzed in mice using the Hamlet test, a novel complex maze.

    Science.gov (United States)

    Crouzier, Lucie; Gilabert, Damien; Rossel, Mireille; Trousse, Françoise; Maurice, Tangui

    2018-03-01

    The Hamlet test is an innovative device providing a complex environment for testing topographic memory in mice. Animals were trained in groups for weeks in a small village with a central agora, streets expanding from it towards five functionalized houses, where they can drink, eat, hide, run, interact with a stranger mouse. Memory was tested by depriving mice from water or food and analyzing their ability to locate the Drink/Eat house. Exploration and memory were analyzed in different strains, gender, and after different training periods and delays. After 2 weeks training, differences in exploration patterns were observed between strains, but not gender. Neuroanatomical structures activated by training, identified using FosB/ΔFosB immunolabelling, showed an involvement of the hippocampus-subiculum-parahippocampal gyrus axis and dopaminergic structures. Training increased hippocampal neurogenesis (cell proliferation and neuronal maturation) and modified the amnesic efficacy of muscarinic or nicotinic cholinergic antagonists. Moreover, topographical disorientation in Alzheimer's disease was addressed using intracerebroventricular injection of amyloid β 25-35 peptide in trained mice. When retested after 7 days, Aβ 25-35 -treated mice showed memory impairment. The Hamlet test specifically allows analysis of topographical memory in mice, based on complex environment. It offers an innovative tool for various ethological or pharmacological research needs. For instance, it allowed to examine topographical disorientation, a warning sign in Alzheimer's disease. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Evaluating the contributions of task expectancy in the testing and guessing benefits on recognition memory.

    Science.gov (United States)

    Huff, Mark J; Yates, Tyler J; Balota, David A

    2018-05-03

    Recently, we have shown that two types of initial testing (recall of a list or guessing of critical items repeated over 12 study/test cycles) improved final recognition of related and unrelated word lists relative to restudy. These benefits were eliminated, however, when test instructions were manipulated within subjects and presented after study of each list, procedures designed to minimise expectancy of a specific type of upcoming test [Huff, Balota, & Hutchison, 2016. The costs and benefits of testing and guessing on recognition memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 42, 1559-1572. doi: 10.1037/xlm0000269 ], suggesting that testing and guessing effects may be influenced by encoding strategies specific for the type of upcoming task. We follow-up these experiments by examining test-expectancy processes in guessing and testing. Testing and guessing benefits over restudy were not found when test instructions were presented either after (Experiment 1) or before (Experiment 2) a single study/task cycle was completed, nor were benefits found when instructions were presented before study/task cycles and the task was repeated three times (Experiment 3). Testing and guessing benefits emerged only when instructions were presented before a study/task cycle and the task was repeated six times (Experiments 4A and 4B). These experiments demonstrate that initial testing and guessing can produce memory benefits in recognition, but only following substantial task repetitions which likely promote task-expectancy processes.

  13. The Test Your Memory for Mild Cognitive Impairment (TYM-MCI).

    Science.gov (United States)

    Brown, Jeremy M; Lansdall, Claire J; Wiggins, Julie; Dawson, Kate E; Hunter, Kristina; Rowe, James B; Parker, Richard A

    2017-12-01

    To validate a short cognitive test: the Test Your Memory for Mild Cognitive Impairment (TYM-MCI) in the diagnosis of patients with amnestic mild cognitive impairment or mild Alzheimer's disease (aMCI/AD). Two hundred and two patients with mild memory problems were recruited. All had 'passed' the Mini-Mental State Examination (MMSE). Patients completed the TYM-MCI, the Test Your Memory test (TYM), MMSE and revised Addenbrooke's Cognitive Examination (ACE-R), had a neurological examination, clinical diagnostics and multidisciplinary team review. As a single test, the TYM-MCI performed as well as the ACE-R in the distinction of patients with aMCI/AD from patients with subjective memory impairment with a sensitivity of 0.79 and specificity of 0.91. Used in combination with the ACE-R, it provided additional value and identified almost all cases of aMCI/AD. The TYM-MCI correctly classified most patients who had equivocal ACE-R scores. Integrated discriminant improvement analysis showed that the TYM-MCI added value to the conventional memory assessment. Patients initially diagnosed as unknown or with subjective memory impairment who were later rediagnosed with aMCI/AD scored poorly on their original TYM-MCI. The TYM-MCI is a powerful short cognitive test that examines verbal and visual recall and is a valuable addition to the assessment of patients with aMCI/AD. It is simple and cheap to administer and requires minimal staff time and training. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. The Category Cued Recall test in very mild Alzheimer's disease: discriminative validity and correlation with semantic memory functions.

    Science.gov (United States)

    Vogel, A; Mortensen, E L; Gade, A; Waldemar, G

    2007-01-01

    Episodic memory tests that measure cued recall may be particularly effective in the diagnosis of early Alzheimer's disease (AD) because they examine both episodic and semantic memory functions. The Category Cued Recall (CCR) test provides superordinate semantic cues at encoding and retrieval, and high discriminative validity has been claimed for this test. The aim of this study was to investigate the discriminative validity for this test when compared with the 10-word memory list from Alzheimer's Disease Assessment Scale (ADAS-cog) that measures free recall. The clinical diagnosis of AD was taken as the standard. It was also investigated whether the two episodic memory tests correlated with measures of semantic memory. The tests were administered to 35 patients with very mild AD (Mini Mental State Examination score >22) and 28 control subjects. Both tests had high sensitivity (>88%) with high specificity (>89%). One out of the five semantic memory tests was significantly correlated to performances on CCR, whereas delayed recall on the ADAS-cog memory test was significantly correlated to two semantic tests. In conclusion, the discriminative validity of the CCR test and the ADAS-cog memory test was equivalent in very mild AD. This may be because CCR did not tap more semantic processes, which are impaired in the earliest phases of AD, than a test of free recall.

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

    Directory of Open Access Journals (Sweden)

    Christof eKuhbandner

    2016-02-01

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

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

    Science.gov (United States)

    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.

  17. [Sexual behaviour and human immunodeficiency virus testing in university students from Cuzco (Peru)].

    Science.gov (United States)

    Bermúdez, M Paz; Ramiro, M Teresa; Teva, Inmaculada; Ramiro-Sánchez, Tamara; Buela-Casal, Gualberto

    To analyse sexual behaviour, HIV testing, HIV testing intentions and reasons for not testing for HIV in university students from Cuzco (Peru). The sample comprised 1,377 university students from several institutions from Cuzco (Peru). The size of the sample was set according to a maximum 3% error estimation and a 97% confidence interval. Ages ranged from 16 to 30 years old. The data were collected through a self-administered, anonymous and voluntary questionnaire regarding sexual behaviour and HIV testing. The data were collected in classrooms during teaching hours. A higher percentage of males than females reported having had vaginal, anal and oral sex, a higher number of sexual partners and an earlier age at first vaginal and oral sex. A higher percentage of females than males did not use condoms when they first had anal sex and had a higher anal sex-risk index. Most of the participants had never been HIV tested. The main reason was that they were sure that they were not HIV infected. It seems that there was a low HIV risk perception in these participants despite the fact that they had been involved in sexual risk behaviours. Prevention campaigns focused on the general population as well as the at-risk populations and young people are needed. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Memories.

    Science.gov (United States)

    Brand, Judith, Ed.

    1998-01-01

    This theme issue of the journal "Exploring" covers the topic of "memories" and describes an exhibition at San Francisco's Exploratorium that ran from May 22, 1998 through January 1999 and that contained over 40 hands-on exhibits, demonstrations, artworks, images, sounds, smells, and tastes that demonstrated and depicted the biological,…

  19. Shape memory alloy resistance behaviour at high altitude for feedback control

    Science.gov (United States)

    Ng, W. T.; Sedan, M. F.; Abdullah, E. J.; Azrad, S.; Harithuddin, A. S. M.

    2017-12-01

    Many recent aerospace technologies are using smart actuators to reduce the system's complexity and increase its reliability. One such actuator is shape memory alloy (SMA) actuator, which is lightweight, produces high force and large deflection. However, some disadvantages in using SMA actuators have been identified and they include nonlinear response of the strain to input current, hysteresis characteristic that results in inaccurate control and less than optimum system performance, high operating temperatures, slow response and also high requirement of electrical power to obtain the desired actuation forces. It is still unknown if the SMA actuators can perform effectively at high altitude with low surrounding temperature. The work presented here covers the preliminary process of verifying the feasibility of using resistance as feedback control at high altitude for aerospace applications. Temperature and resistance of SMA actuator at high altitude is investigated by conducting an experiment onboard a high altitude balloon. The results from the high altitude experiment indicate that the resistance or voltage drop of the SMA wire is not significantly affected by the low surrounding temperature at high altitude as compared to the temperature of SMA. Resistance feedback control for SMA actuators may be suitable for aerospace applications.

  20. Cerebral networks of sustained attention and working memory: a functional magnetic resonance imaging study based on the Continuous Performance Test.

    Science.gov (United States)

    Bartés-Serrallonga, M; Adan, A; Solé-Casals, J; Caldú, X; Falcón, C; Pérez-Pàmies, M; Bargalló, N; Serra-Grabulosa, J M

    2014-04-01

    One of the most used paradigms in the study of attention is the Continuous Performance Test (CPT). The identical pairs version (CPT-IP) has been widely used to evaluate attention deficits in developmental, neurological and psychiatric disorders. However, the specific locations and the relative distribution of brain activation in networks identified with functional imaging, varies significantly with differences in task design. To design a task to evaluate sustained attention using functional magnetic resonance imaging (fMRI), and thus to provide data for research concerned with the role of these functions. Forty right-handed, healthy students (50% women; age range: 18-25 years) were recruited. A CPT-IP implemented as a block design was used to assess sustained attention during the fMRI session. The behavioural results from the CPT-IP task showed a good performance in all subjects, higher than 80% of hits. fMRI results showed that the used CPT-IP task activates a network of frontal, parietal and occipital areas, and that these are related to executive and attentional functions. In relation to the use of the CPT to study of attention and working memory, this task provides normative data in healthy adults, and it could be useful to evaluate disorders which have attentional and working memory deficits.

  1. Lesser Neural Pattern Similarity across Repeated Tests Is Associated with Better Long-Term Memory Retention.

    Science.gov (United States)

    Karlsson Wirebring, Linnea; Wiklund-Hörnqvist, Carola; Eriksson, Johan; Andersson, Micael; Jonsson, Bert; Nyberg, Lars

    2015-07-01

    Encoding and retrieval processes enhance long-term memory performance. The efficiency of encoding processes has recently been linked to representational consistency: the reactivation of a representation that gets more specific each time an item is further studied. Here we examined the complementary hypothesis of whether the efficiency of retrieval processes also is linked to representational consistency. Alternatively, recurrent retrieval might foster representational variability--the altering or adding of underlying memory representations. Human participants studied 60 Swahili-Swedish word pairs before being scanned with fMRI the same day and 1 week later. On Day 1, participants were tested three times on each word pair, and on Day 7 each pair was tested once. A BOLD signal change in right superior parietal cortex was associated with subsequent memory on Day 1 and with successful long-term retention on Day 7. A representational similarity analysis in this parietal region revealed that beneficial recurrent retrieval was associated with representational variability, such that the pattern similarity on Day 1 was lower for retrieved words subsequently remembered compared with those subsequently forgotten. This was mirrored by a monotonically decreased BOLD signal change in dorsolateral prefrontal cortex on Day 1 as a function of repeated successful retrieval for words subsequently remembered, but not for words subsequently forgotten. This reduction in prefrontal response could reflect reduced demands on cognitive control. Collectively, the results offer novel insights into why memory retention benefits from repeated retrieval, and they suggest fundamental differences between repeated study and repeated testing. Repeated testing is known to produce superior long-term retention of the to-be-learned material compared with repeated encoding and other learning techniques, much because it fosters repeated memory retrieval. This study demonstrates that repeated memory

  2. Psychophysiology of prospective memory.

    Science.gov (United States)

    Rothen, Nicolas; Meier, Beat

    2014-01-01

    Prospective memory involves the self-initiated retrieval of an intention upon an appropriate retrieval cue. Cue identification can be considered as an orienting reaction and may thus trigger a psychophysiological response. Here we present two experiments in which skin conductance responses (SCRs) elicited by prospective memory cues were compared to SCRs elicited by aversive stimuli to test whether a single prospective memory cue triggers a similar SCR as an aversive stimulus. In Experiment 2 we also assessed whether cue specificity had a differential influence on prospective memory performance and on SCRs. We found that detecting a single prospective memory cue is as likely to elicit a SCR as an aversive stimulus. Missed prospective memory cues also elicited SCRs. On a behavioural level, specific intentions led to better prospective memory performance. However, on a psychophysiological level specificity had no influence. More generally, the results indicate reliable SCRs for prospective memory cues and point to psychophysiological measures as valuable approach, which offers a new way to study one-off prospective memory tasks. Moreover, the findings are consistent with a theory that posits multiple prospective memory retrieval stages.

  3. 'I feel better when…': An analysis of the memory-experience gap for peoples' estimates of the relationship between health behaviours and experiences.

    Science.gov (United States)

    Gloster, Andrew T; Meyer, Andrea H; Witthauer, Cornelia; Lieb, Roselind; Mata, Jutta

    2017-09-01

    People often overestimate how strongly behaviours and experiences are related. This memory-experience gap might have important implications for health care settings, which often require people to estimate associations, such as "my mood is better when I exercise". This study examines how subjective correlation estimates between health behaviours and experiences relate to calculated correlations from online reports and whether subjective estimates are associated with engagement in actual health behaviour. Seven-month online study on physical activity, sleep, affect and stress, with 61 online assessments. University students (N = 168) retrospectively estimated correlations between physical activity, sleep, positive affect and stress over the seven-month study period. Correlations between experiences and behaviours (online data) were small (r = -.12-.14), estimated correlations moderate (r = -.35-.24). Correspondence between calculated and estimated correlations was low. Importantly, estimated correlations of physical activity with stress, positive affect and sleep were associated with actual engagement in physical activity. Estimation accuracy of relations between health behaviours and experiences is low. However, association estimates could be an important predictor of actual health behaviours. This study identifies and quantifies estimation inaccuracies in health behaviours and points towards potential systematic biases in health settings, which might seriously impair intervention efficacy.

  4. Coupling method of magnetic memory and eddy current nondestructive testing for retired crankshafts

    Energy Technology Data Exchange (ETDEWEB)

    Ni, Chen; Hua, Lin; Wang, Xiaokai; Wang, Zhou; Qin, Xunpeng; Fang, Zhou [Wuhan University of Technology, Wuhan (Korea, Republic of)

    2016-07-15

    To verify the validity of the Coupling method of magnetic memory and eddy current (CMMEC) testing for crankshafts, we use this technique to test a 12-cylinder V-design diesel crankshaft. First, the stress distribution in the crankshaft was obtained under 12 working conditions using a Finite element (FE) model that complied with the commercial FE code ABAQUS. Second, Magnetic memory testing (MMT) and Eddy current testing (ECT) were adopted to detect the regions of stress concentration in the crankshaft and the specific location of cracks based on simulation results. Lastly, magnetic particle testing was conducted to detect and display the corresponding crack to verify the CMMEC testing results. The MMT and ECT results can provide basis and guidance for the remanufacture and life evaluation of retired crankshafts.

  5. Coupling method of magnetic memory and eddy current nondestructive testing for retired crankshafts

    International Nuclear Information System (INIS)

    Ni, Chen; Hua, Lin; Wang, Xiaokai; Wang, Zhou; Qin, Xunpeng; Fang, Zhou

    2016-01-01

    To verify the validity of the Coupling method of magnetic memory and eddy current (CMMEC) testing for crankshafts, we use this technique to test a 12-cylinder V-design diesel crankshaft. First, the stress distribution in the crankshaft was obtained under 12 working conditions using a Finite element (FE) model that complied with the commercial FE code ABAQUS. Second, Magnetic memory testing (MMT) and Eddy current testing (ECT) were adopted to detect the regions of stress concentration in the crankshaft and the specific location of cracks based on simulation results. Lastly, magnetic particle testing was conducted to detect and display the corresponding crack to verify the CMMEC testing results. The MMT and ECT results can provide basis and guidance for the remanufacture and life evaluation of retired crankshafts.

  6. Results from On-Orbit Testing of the Fram Memory Test Experiment on the Fastsat Micro-Satellite

    Science.gov (United States)

    MacLeod, Todd C.; Sims, W. Herb; Varnavas, Kosta A.; Ho, Fat D.

    2011-01-01

    NASA is planning on going beyond Low Earth orbit with manned exploration missions. The radiation environment for most Low Earth orbit missions is harsher than at the Earth's surface but much less harsh than deep space. Development of new electronics is needed to meet the requirements of high performance, radiation tolerance, and reliability. The need for both Volatile and Non-volatile memory has been identified. Emerging Non-volatile memory technologies (FRAM, C-RAM,M-RAM, R-RAM, Radiation Tolerant FLASH, SONOS, etc.) need to be investigated for use in Space missions. An opportunity arose to fly a small memory experiment on a high inclination satellite (FASTSAT). An off-the-shelf 512K Ramtron FRAM was chosen to be tested in the experiment.

  7. Study on influence of radiation on learning and memory behaviours in prenatally-irradiated rats and its possible mechanism

    International Nuclear Information System (INIS)

    Guo Yuefeng; Yang Zhiyuan; Liu Jingwen; Wang Mingming

    1995-01-01

    Pregnent Wistar rats were exposed on day 11 of gestation to 137 Cs γ-rays, the doses absorbed by their offsprings were estimated to be 0.015, 0.15, 0.41, 0.91 or 2.2 Gy. The influence of radiation on their postnatal learning and memory behaviours, and number of pyramidal cells and content of free hydroxyproline in the hippocampus of brain was observed. The results show that for offsprings with doses of 0.15-2.2 Gy, the average daily frequency of conditional drinking response which can meet the assigned criteria was significantly lower than that for controls and the degree of reduction increased with doses, and that for these offsprings, there was a significant decrease in number of pyramidal cells, with a marked increase in content of free hydroxyproline which is in proportion to doses. The relationship of change in either number of pyramidal cells or content of free hydroxypreline in hippocampus with doses can be expressed as equation of Y A + BlgD

  8. Application of complex programmable logic devices in memory radiation effects test system

    International Nuclear Information System (INIS)

    Li Yonghong; He Chaohui; Yang Hailiang; He Baoping

    2005-01-01

    The application of the complex programmable logic device (CPLD) in electronics is emphatically discussed. The method of using software MAX + plus II and CPLD are introduced. A new test system for memory radiation effects is established by using CPLD devices-EPM7128C84-15. The old test system's function are realized and, moreover, a number of small scale integrated circuits are reduced and the test system's reliability is improved. (authors)

  9. Aged Tg2576 mice are impaired on social memory and open field habituation tests.

    Science.gov (United States)

    Deacon, R M J; Koros, E; Bornemann, K D; Rawlins, J N P

    2009-02-11

    In a previous publication [Deacon RMJ, Cholerton LL, Talbot K, Nair-Roberts RG, Sanderson DJ, Romberg C, et al. Age-dependent and -independent behavioral deficits in Tg2576 mice. Behav Brain Res 2008;189:126-38] we found that very few cognitive tests were suitable for demonstrating deficits in Tg2576 mice, an amyloid over-expression model of Alzheimer's disease, even at 23 months of age. However, in a retrospective analysis of a separate project on these mice, tests of social memory and open field habituation revealed large cognitive impairments. Controls showed good open field habituation, but Tg2576 mice were hyperactive and failed to habituate. In the test of social memory for a juvenile mouse, controls showed considerably less social investigation on the second meeting, indicating memory of the juvenile, whereas Tg2576 mice did not show this decrement.As a control for olfactory sensitivity, on which social memory relies, the ability to find a food pellet hidden under wood chip bedding was assessed. Tg2576 mice found the pellet as quickly as controls. As this test requires digging ability, this was independently assessed in tests of burrowing and directly observed digging. In line with previous results and the hippocampal dysfunction characteristic of aged Tg2576 mice, they both burrowed and dug less than controls.

  10. On the behaviour of dissolved fission gases prior to transient testing of fuel pins

    International Nuclear Information System (INIS)

    Wood, M.H.; Matthews, J.R.

    1978-10-01

    The TREAT and CABRI series of reactor safety experiments on irradiated fuel require the transfer of fuel pins from the reactor in which the fuel has achieved some burn-up to the test facility. Subsequently, the fuel is restored to power in the test facility for some time before transient heating is initiated. Such pre-test manoeuvres, where the fuel is subjected to changes in the fission rate and temperature, may have important consequences for the fission gas behaviour during the transient experiment. The results of rate theory calculations are used to assess these effects. (author)

  11. Temporal lobe volume predicts Wada memory test performance in patients with mesial temporal sclerosis.

    Science.gov (United States)

    Ding, Kan; Gong, Yunhua; Modur, Pradeep N; Diaz-Arrastia, Ramon; Agostini, Mark; Gupta, Puneet; McColl, Roderick; Hays, Ryan; Van Ness, Paul

    2016-02-01

    The Wada test is widely used in the presurgical evaluation of potential temporal lobectomy patients to predict postoperative memory function. Expected asymmetry (EA), defined as Wada memory lateralized to the nonsurgical hemisphere, or a higher score after injection of the surgical hemisphere would be considered favorable in terms of postoperative memory outcome. However, in some cases, nonlateralized memory (NM) results, with no appreciable asymmetry, may occur because of impaired scores after both injections, often leading to denial of surgery. The reason for such nonlateralized Wada memory in patients with intractable temporal lobe epilepsy (TLE) remains unclear. Given that quantitative morphometric magnetic resonance imaging studies in TLE patients have shown bilateral regional atrophy in temporal and extratemporal structures, we hypothesized that the volume loss in contralateral temporal structures could contribute to nonlateralized Wada memory performance. To investigate this, we examined the relationship between the volume changes of temporal structures and Wada memory scores in patients with intractable TLE with mesial temporal sclerosis (MTS) using an age- and gender-matched control group. Memory was considered nonlateralized if the absolute difference in the total correct recall scores between ipsilateral and contralateral injections was memory was lateralized in 15 and nonlateralized in 6 patients, with all the nonlateralized scores being observed in left TLE. The recall scores after ipsilateral injection were significantly lower in patients with an NM profile than an EA profile (23 ± 14% vs. 59 ± 18% correct recall, p ≤ 0.001). However, the recall scores after contralateral injection were low but similar between the two groups (25 ± 17% vs. 25 ± 15% correct recall, p=0.97). Compared to controls, all the patients showed greater volume loss in the temporal regions. However, patients with a NM profile showed significantly more volume loss than those

  12. Relational Memory Is Evident in Eye Movement Behavior despite the Use of Subliminal Testing Methods.

    Directory of Open Access Journals (Sweden)

    Allison E Nickel

    Full Text Available While it is generally agreed that perception can occur without awareness, there continues to be debate about the type of representational content that is accessible when awareness is minimized or eliminated. Most investigations that have addressed this issue evaluate access to well-learned representations. Far fewer studies have evaluated whether or not associations encountered just once prior to testing might also be accessed and influence behavior. Here, eye movements were used to examine whether or not memory for studied relationships is evident following the presentation of subliminal cues. Participants assigned to experimental or control groups studied scene-face pairs and test trials evaluated implicit and explicit memory for these pairs. Each test trial began with a subliminal scene cue, followed by three visible studied faces. For experimental group participants, one face was the studied associate of the scene (implicit test; for controls none were a match. Subsequently, the display containing a match was presented to both groups, but now it was preceded by a visible scene cue (explicit test. Eye movements were recorded and recognition memory responses were made. Participants in the experimental group looked disproportionately at matching faces on implicit test trials and participants from both groups looked disproportionately at matching faces on explicit test trials, even when that face had not been successfully identified as the associate. Critically, implicit memory-based viewing effects seemed not to depend on residual awareness of subliminal scene cues, as subjective and objective measures indicated that scenes were successfully masked from view. The reported outcomes indicate that memory for studied relationships can be expressed in eye movement behavior without awareness.

  13. Relational Memory Is Evident in Eye Movement Behavior despite the Use of Subliminal Testing Methods

    Science.gov (United States)

    Nickel, Allison E.; Henke, Katharina; Hannula, Deborah E.

    2015-01-01

    While it is generally agreed that perception can occur without awareness, there continues to be debate about the type of representational content that is accessible when awareness is minimized or eliminated. Most investigations that have addressed this issue evaluate access to well-learned representations. Far fewer studies have evaluated whether or not associations encountered just once prior to testing might also be accessed and influence behavior. Here, eye movements were used to examine whether or not memory for studied relationships is evident following the presentation of subliminal cues. Participants assigned to experimental or control groups studied scene-face pairs and test trials evaluated implicit and explicit memory for these pairs. Each test trial began with a subliminal scene cue, followed by three visible studied faces. For experimental group participants, one face was the studied associate of the scene (implicit test); for controls none were a match. Subsequently, the display containing a match was presented to both groups, but now it was preceded by a visible scene cue (explicit test). Eye movements were recorded and recognition memory responses were made. Participants in the experimental group looked disproportionately at matching faces on implicit test trials and participants from both groups looked disproportionately at matching faces on explicit test trials, even when that face had not been successfully identified as the associate. Critically, implicit memory-based viewing effects seemed not to depend on residual awareness of subliminal scene cues, as subjective and objective measures indicated that scenes were successfully masked from view. The reported outcomes indicate that memory for studied relationships can be expressed in eye movement behavior without awareness. PMID:26512726

  14. Relational Memory Is Evident in Eye Movement Behavior despite the Use of Subliminal Testing Methods.

    Science.gov (United States)

    Nickel, Allison E; Henke, Katharina; Hannula, Deborah E

    2015-01-01

    While it is generally agreed that perception can occur without awareness, there continues to be debate about the type of representational content that is accessible when awareness is minimized or eliminated. Most investigations that have addressed this issue evaluate access to well-learned representations. Far fewer studies have evaluated whether or not associations encountered just once prior to testing might also be accessed and influence behavior. Here, eye movements were used to examine whether or not memory for studied relationships is evident following the presentation of subliminal cues. Participants assigned to experimental or control groups studied scene-face pairs and test trials evaluated implicit and explicit memory for these pairs. Each test trial began with a subliminal scene cue, followed by three visible studied faces. For experimental group participants, one face was the studied associate of the scene (implicit test); for controls none were a match. Subsequently, the display containing a match was presented to both groups, but now it was preceded by a visible scene cue (explicit test). Eye movements were recorded and recognition memory responses were made. Participants in the experimental group looked disproportionately at matching faces on implicit test trials and participants from both groups looked disproportionately at matching faces on explicit test trials, even when that face had not been successfully identified as the associate. Critically, implicit memory-based viewing effects seemed not to depend on residual awareness of subliminal scene cues, as subjective and objective measures indicated that scenes were successfully masked from view. The reported outcomes indicate that memory for studied relationships can be expressed in eye movement behavior without awareness.

  15. The Doors and People Test: The effect of frontal lobe lesions on recall and recognition memory performance.

    Science.gov (United States)

    MacPherson, Sarah E; Turner, Martha S; Bozzali, Marco; Cipolotti, Lisa; Shallice, Tim

    2016-03-01

    Memory deficits in patients with frontal lobe lesions are most apparent on free recall tasks that require the selection, initiation, and implementation of retrieval strategies. The effect of frontal lesions on recognition memory performance is less clear with some studies reporting recognition memory impairments but others not. The majority of these studies do not directly compare recall and recognition within the same group of frontal patients, assessing only recall or recognition memory performance. Other studies that do compare recall and recognition in the same frontal group do not consider recall or recognition tests that are comparable for difficulty. Recognition memory impairments may not be reported because recognition memory tasks are less demanding. This study aimed to investigate recall and recognition impairments in the same group of 47 frontal patients and 78 healthy controls. The Doors and People Test was administered as a neuropsychological test of memory as it assesses both verbal and visual recall and recognition using subtests that are matched for difficulty. Significant verbal and visual recall and recognition impairments were found in the frontal patients. These results demonstrate that when frontal patients are assessed on recall and recognition memory tests of comparable difficulty, memory impairments are found on both types of episodic memory test. (c) 2016 APA, all rights reserved).

  16. Results of tests under normal and abnormal operating conditions concerning LMFBR fuel element behaviour

    International Nuclear Information System (INIS)

    Languille, A.; Bergeonneau, P.; Essig, C.; Guerin, Y.

    1985-04-01

    The objective of this paper is to improve the knowledge on LMFBR fuel element behaviour during protected and unprotected transients in RAPSODIE and PHENIX reactors in order to evaluate its reliability. The range of the tests performed in these reactors is sufficiently large to cover normal and also extreme off normal conditions such as fuel melting. Results of such tests allow to better establish transient design limits for reactor structural components in particular for fuel pin cladding which play a lead role in controlling the accident sequence. Three main topics are emphasized in this paper: fuel melting during slow over-power excursions; influence of the fuel element geometrical evolution on reactivity feedback effects and reactor dynamic behaviour; clad damage evaluation during a transient (essentially very severe loss of flow)

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

    Directory of Open Access Journals (Sweden)

    VALERIA eCOLAVITO

    2013-12-01

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

  18. Working memory, attentional regulation and the Star Counting Test.

    NARCIS (Netherlands)

    Das-Smaal, E.A.; Jong, de P.F.; Koopmans, J.R.

    1993-01-01

    The Star Counting Test (SCT) has been developed to measure the regulatory function of attention. In a previous study it was shown that the SCT is suited for assessment of this attentional aspect with children. The present study concerns a more difficult version aimed at young adults. In the

  19. Simultaneous Versus Sequential Presentation in Testing Recognition Memory for Faces.

    Science.gov (United States)

    Finley, Jason R; Roediger, Henry L; Hughes, Andrea D; Wahlheim, Christopher N; Jacoby, Larry L

    2015-01-01

    Three experiments examined the issue of whether faces could be better recognized in a simul- taneous test format (2-alternative forced choice [2AFC]) or a sequential test format (yes-no). All experiments showed that when target faces were present in the test, the simultaneous procedure led to superior performance (area under the ROC curve), whether lures were high or low in similarity to the targets. However, when a target-absent condition was used in which no lures resembled the targets but the lures were similar to each other, the simultaneous procedure yielded higher false alarm rates (Experiments 2 and 3) and worse overall performance (Experi- ment 3). This pattern persisted even when we excluded responses that participants opted to withhold rather than volunteer. We conclude that for the basic recognition procedures used in these experiments, simultaneous presentation of alternatives (2AFC) generally leads to better discriminability than does sequential presentation (yes-no) when a target is among the alterna- tives. However, our results also show that the opposite can occur when there is no target among the alternatives. An important future step is to see whether these patterns extend to more realistic eyewitness lineup procedures. The pictures used in the experiment are available online at http://www.press.uillinois.edu/journals/ajp/media/testing_recognition/.

  20. Household Intertemporal Behaviour: A Collective Characterization and a Test of Commitment

    OpenAIRE

    Maurizio Mazzocco

    2007-01-01

    In this paper, a formal test of intra-household commitment is derived and performed. To that end, two models of household intertemporal behaviour are developed. In both models, household members are characterized by individual preferences. In the first formulation, household decisions are always on the ex ante Pareto frontier. In the second model, the assumption of intra-household commitment required by ex ante efficiency is relaxed. It is shown that the full-efficiency household Euler equati...

  1. Verbal memory improved by D-amphetamine: influence of the testing effect.

    Science.gov (United States)

    Zeeuws, Inge; Deroost, Natacha; Soetens, Eric

    2010-07-01

    The improvement of long-term retention of verbal memory after an acute administration of D-amphetamine in recall and recognition tasks has been ascribed to an influence of the drug on memory consolidation. Because recent research has demonstrated that intermediate testing is of overriding importance for retention, we investigated whether D-amphetamine modulates the repeated testing effect in verbal long-term recognition. Forty men participated in two double blind placebo controlled studies. In Experiment 1, we manipulated the number of recognition tests and in Experiment 2, we compared repeated with nonrepeated testing of the same items. Drug effects were observed on delayed tests only, leaving immediate recognition unaffected. Number of intermediate recognition tests and repeated testing of the same items were not affected by D-amphetamine. We conclude that the D-amphetamine memory enhancement is not related to the testing effect. This result supports that D-amphetamine modulates other aspects of the consolidation process, probably related to context effects. (c) 2010 John Wiley & Sons, Ltd.

  2. TESTING THE EFFECTS OF THE IMIDAZOPYRIDINE ZOLPIDEM ON MEMORY : AN ECOLOGICALLY VALID APPROACH

    NARCIS (Netherlands)

    Jackson, JL; Louwerens, JW; Cnossen, F; de Jong, HTP

    1992-01-01

    The present study explores whether memory impairments are found on the morning following intake of the hypnotic zolpidem which is a member of a new pharmaceutical class, the imidazopyridines. The procedure used is novel: it involves testing subjects in their own homes via the telephone. A previous

  3. Sensitivity and specificity of the 3-item memory test in the assessment of post traumatic amnesia.

    NARCIS (Netherlands)

    Andriessen, T.M.J.C.; Jong, B. de; Jacobs, B.; Werf, S.P. van der; Vos, P.E.

    2009-01-01

    PRIMARY OBJECTIVE: To investigate how the type of stimulus (pictures or words) and the method of reproduction (free recall or recognition after a short or a long delay) affect the sensitivity and specificity of a 3-item memory test in the assessment of post traumatic amnesia (PTA). METHODS: Daily

  4. Developmental Differences in Recall and Recognition: The Relationship between Rehearsal and Memory as Test Expectation Changes

    Science.gov (United States)

    Naus, Mary J.; And Others

    1977-01-01

    An overt rehearsal procedure was used to study the relationship between 48 third- and 48 sixth-grade children's rehearsal strategies and their memory performance under difficult conditions of test expectation. This study addressed the question of why active rehearsal content results in superior recall performances. (MS)

  5. Testing complex animal cognition: Concept learning, proactive interference, and list memory.

    Science.gov (United States)

    Wright, Anthony A

    2018-01-01

    This article describes an approach for assessing and comparing complex cognition in rhesus monkeys and pigeons by training them in a sequence of synergistic tasks, each yielding a whole function for enhanced comparisons. These species were trained in similar same/different tasks with expanding training sets (8, 16, 32, 64, 128 … 1024 pictures) followed by novel-stimulus transfer eventually resulting in full abstract-concept learning. Concept-learning functions revealed better rhesus transfer throughout and full concept learning at the 128 set, versus pigeons at the 256 set. They were then tested in delayed same/different tasks for proactive interference by inserting occasional tests within trial-unique sessions where the test stimulus matched a previous sample stimulus (1, 2, 4, 8, 16 trials prior). Proactive-interference functions revealed time-based interference for pigeons (1, 10 s delays), but event-based interference for rhesus (no effect of 1, 10, 20 s delays). They were then tested in list-memory tasks by expanding the sample to four samples in trial-unique sessions (minimizing proactive interference). The four-item, list-memory functions revealed strong recency memory at short delays, gradually changing to strong primacy memory at long delays over 30 s for rhesus, and 10 s for pigeons. Other species comparisons and future directions are discussed. © 2018 Society for the Experimental Analysis of Behavior.

  6. How Memory Is Tested Influences What Is Measured: Reply to Wyble and Chen (2017)

    Science.gov (United States)

    Swallow, Khena M.; Jiang, Yuhong V.; Tan, Deborah H.

    2017-01-01

    In this response to Wyble and Chen's (2017) commentary on attribute amnesia, we hope to achieve several goals. First, we clarify how our view diverges from that described by Wyble and Chen. We argue that because the surprise memory test is disruptive, it is an insensitive tool for measuring the persistence of recently attended target attributes in…

  7. TESTING THE EFFECTS OF HYPNOTICS ON MEMORY VIA THE TELEPHONE : FACT OR FICTION

    NARCIS (Netherlands)

    Jackson, JL; Louwerens, JW; Cnossen, F; de Jong, HTP

    The two benzodiazapines used in this experiment, namely midazolam and flunitrazepam, have both been shown to have effects on memory processing in laboratory studies. In spite of the potential hazards involved in real life testing, it should be possible to replicate such findings in everyday

  8. Dynamic Testing, Working Memory, and Reading Comprehension Growth in Children with Reading Disabilities

    Science.gov (United States)

    Swanson, H. Lee

    2011-01-01

    This longitudinal study assessed (a) whether performance changes in working memory (WM) as a function of dynamic testing were related to growth in reading comprehension and (b) whether WM performance among subgroups of children with reading disabilities (RD; children with RD only, children with both reading and arithmetic deficits, and low verbal…

  9. Steps Leading to an Ethnographic Analysis of Mothers Preparing Children for a Memory Test.

    Science.gov (United States)

    Rogoff, Barbara; Gardner, William P.

    In this study four research strategies used in previous studies of the socialization of cognitive skills were first contrasted and then assessed in terms of five criteria. (The data base for this study was 32 videotapes of mothers preparing their 7- or 9-year-old children to take a memory test.) The four strategies (frequency coding, fine-grained…

  10. An online study combining the constructs from the theory of planned behaviour and protection motivation theory in predicting intention to test for chlamydia in two testing contexts.

    Science.gov (United States)

    Powell, Rachael; Pattison, Helen M; Francis, Jill J

    2016-01-01

    Chlamydia is a common sexually transmitted infection that has potentially serious consequences unless detected and treated early. The health service in the UK offers clinic-based testing for chlamydia but uptake is low. Identifying the predictors of testing behaviours may inform interventions to increase uptake. Self-tests for chlamydia may facilitate testing and treatment in people who avoid clinic-based testing. Self-testing and being tested by a health care professional (HCP) involve two contrasting contexts that may influence testing behaviour. However, little is known about how predictors of behaviour differ as a function of context. In this study, theoretical models of behaviour were used to assess factors that may predict intention to test in two different contexts: self-testing and being tested by a HCP. Individuals searching for or reading about chlamydia testing online were recruited using Google Adwords. Participants completed an online questionnaire that addressed previous testing behaviour and measured constructs of the Theory of Planned Behaviour and Protection Motivation Theory, which propose a total of eight possible predictors of intention. The questionnaire was completed by 310 participants. Sufficient data for multiple regression were provided by 102 and 118 respondents for self-testing and testing by a HCP respectively. Intention to self-test was predicted by vulnerability and self-efficacy, with a trend-level effect for response efficacy. Intention to be tested by a HCP was predicted by vulnerability, attitude and subjective norm. Thus, intentions to carry out two testing behaviours with very similar goals can have different predictors depending on test context. We conclude that interventions to increase self-testing should be based on evidence specifically related to test context.

  11. Habitat stability, predation risk and 'memory syndromes'.

    Science.gov (United States)

    Dalesman, S; Rendle, A; Dall, S R X

    2015-05-27

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonstrates consistency among memory traits ('memory syndrome') related to threat avoidance and foraging. We used eight populations originating from three different habitat types: i) laboratory populations (stable habitat, predator-free); ii) river populations (fairly stable habitat, fish predation); and iii) ditch populations (unstable habitat, invertebrate predation). At a population level, there was a negative relationship between memories related to threat avoidance and food selectivity, but no consistency within habitat type. At an individual level, covariance between memory traits was dependent on habitat. Laboratory populations showed no covariance among memory traits, whereas river populations showed a positive correlation between food memories, and ditch populations demonstrated a negative relationship between threat memory and food memories. Therefore, selection pressures among habitats appear to act independently on memory trait covariation at an individual level and the average response within a population.

  12. Exact and conceptual repetition dissociate conceptual memory tests: problems for transfer appropriate processing theory.

    Science.gov (United States)

    McDermott, K B; Roediger, H L

    1996-03-01

    Three experiments examined whether a conceptual implicit memory test (specifically, category instance generation) would exhibit repetition effects similar to those found in free recall. The transfer appropriate processing account of dissociations among memory tests led us to predict that the tests would show parallel effects; this prediction was based upon the theory's assumption that conceptual tests will behave similarly as a function of various independent variables. In Experiment 1, conceptual repetition (i.e., following a target word [e.g., puzzles] with an associate [e.g., jigsaw]) did not enhance priming on the instance generation test relative to the condition of simply presenting the target word once, although this manipulation did affect free recall. In Experiment 2, conceptual repetition was achieved by following a picture with its corresponding word (or vice versa). In this case, there was an effect of conceptual repetition on free recall but no reliable effect on category instance generation or category cued recall. In addition, we obtained a picture superiority effect in free recall but not in category instance generation. In the third experiment, when the same study sequence was used as in Experiment 1, but with instructions that encouraged relational processing, priming on the category instance generation task was enhanced by conceptual repetition. Results demonstrate that conceptual memory tests can be dissociated and present problems for Roediger's (1990) transfer appropriate processing account of dissociations between explicit and implicit tests.

  13. Visual working memory and number sense: Testing the double deficit hypothesis in mathematics.

    Science.gov (United States)

    Toll, Sylke W M; Kroesbergen, Evelyn H; Van Luit, Johannes E H

    2016-09-01

    Evidence exists that there are two main underlying cognitive factors in mathematical difficulties: working memory and number sense. It is suggested that real math difficulties appear when both working memory and number sense are weak, here referred to as the double deficit (DD) hypothesis. The aim of this study was to test the DD hypothesis within a longitudinal time span of 2 years. A total of 670 children participated. The mean age was 4.96 years at the start of the study and 7.02 years at the end of the study. At the end of the first year of kindergarten, both visual-spatial working memory and number sense were measured by two different tasks. At the end of first grade, mathematical performance was measured with two tasks, one for math facts and one for math problems. Multiple regressions revealed that both visual working memory and symbolic number sense are predictors of mathematical performance in first grade. Symbolic number sense appears to be the strongest predictor for both math areas (math facts and math problems). Non-symbolic number sense only predicts performance in math problems. Multivariate analyses of variance showed that a combination of visual working memory and number sense deficits (NSDs) leads to the lowest performance on mathematics. Our DD hypothesis was confirmed. Both visual working memory and symbolic number sense in kindergarten are related to mathematical performance 2 years later, and a combination of visual working memory and NSDs leads to low performance in mathematical performance. © 2016 The British Psychological Society.

  14. Investigating the mixture and subdivision of perceptual and conceptual processing in Japanese memory tests.

    Science.gov (United States)

    Gabeza, R

    1995-03-01

    The dual nature of the Japanese writing system was used to investigate two assumptions of the processing view of memory transfer: (1) that both perceptual and conceptual processing can contribute to the same memory test (mixture assumption) and (2) that both can be broken into more specific processes (subdivision assumption). Supporting the mixture assumption, a word fragment completion test based on ideographic kanji characters (kanji fragment completion test) was affected by both perceptual (hiragana/kanji script shift) and conceptual (levels-of-processing) study manipulations kanji fragments, because it did not occur with the use of meaningless hiragana fragments. The mixture assumption is also supported by an effect of study script on an implicit conceptual test (sentence completion), and the subdivision assumption is supported by a crossover dissociation between hiragana and kanji fragment completion as a function of study script.

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

    Directory of Open Access Journals (Sweden)

    Estela eCamara

    2014-11-01

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

  16. Validation of a Spanish version of the Test Your Memory.

    Science.gov (United States)

    Ferrero-Arias, J; Turrión-Rojo, M Á

    2016-01-01

    To validate a Spanish version of the TYM, a self-administered cognitive screening test designed for the detection of Alzheimer's disease and mild cognitive defect. A cross-sectional study was conducted in a neurology outpatient clinic. The TYM was administered to individuals of 50 years o more who came to the clinic for whatever the symptom. Their cognitive state was evaluated regardless of the outcome of TYM. They were categorized into 3 groups: 1) Cognitively normal (739), 2) with mild cognitive impairment (183), 3) with dementia (127). An analysis of items was made and the psychometric properties of the TYM were defined. There was a cross-validation, and the predictive validity of the TYM score, adjusted to the demographic variables, was determined by evaluating their performance in ROC curves. The internal consistency, interobserver reliability, short term and long-term test-retest reliability were adequate. The TYM correlated with the MMSE (r=0.779, Pde Neurología. Published by Elsevier España, S.L.U. All rights reserved.

  17. Effect of direct-to-consumer genetic tests on health behaviour and anxiety: a survey of consumers and potential consumers.

    Science.gov (United States)

    Egglestone, Corin; Morris, Anne; O'Brien, Ann

    2013-10-01

    Direct-to-consumer (DTC) genetic tests can be purchased over the internet. Some companies claim to provide relative genetic risks for various diseases and thus encourage healthy behaviour. There are concerns that exposure to such information may actually discourage healthy behaviour or increase health anxiety. An online survey was conducted (n = 275). Respondents were composed of individuals who had purchased a DTC genetic test and received their results (consumers, n = 189), as well as individuals who were either awaiting test results or considering purchasing a test (potential consumers, n = 86). Consumers were asked if their health behaviour or health anxiety had changed after receiving their results. Respondents' current health behaviour and health anxiety were queried and compared. In total, 27.3 % of consumers claimed a change in health behaviour, all either positive or neutral, with no reported cessation of any existing health behaviour. A change in health anxiety was claimed by 24.6 % of consumers, 85.3 % of which were a reduction. Consumers had significantly better health behaviour scores than potential consumers (p = 0.02), with no significant difference in health anxiety. This study points towards an association between receipt of DTC genetic test results and increased adoption of healthy behaviours for a minority of consumers based on self-report, with more mixed results in relation to health anxiety.

  18. Working Memory Capacity: Attention Control, Secondary Memory, or Both? A Direct Test of the Dual-Component Model

    Science.gov (United States)

    Unsworth, Nash; Spillers, Gregory J.

    2010-01-01

    The current study examined the extent to which attention control abilities, secondary memory abilities, or both accounted for variation in working memory capacity (WMC) and its relation to fluid intelligence. Participants performed various attention control, secondary memory, WMC, and fluid intelligence measures. Confirmatory factor analyses…

  19. How does additional diagnostic testing influence the initial diagnosis in patients with cognitive complaints in a memory clinic setting?

    NARCIS (Netherlands)

    Meijs, A.P.; Claassen, J.A.H.R.; Olde Rikkert, M.G.M.; Schalk, B.W.M; Meulenbroek, O.V.; Kessels, R.P.C.; Melis, R.J.F.

    2015-01-01

    Background: patients suspected of dementia frequently undergo additional diagnostic testing (e.g. brain imaging or neuropsychological assessment) after standard clinical assessment at a memory clinic. This study investigates the use of additional testing in an academic outpatient memory clinic and

  20. How does additional diagnostic testing influence the initial diagnosis in patients with cognitive complaints in a memory clinic setting?

    NARCIS (Netherlands)

    Meijs, A.P.; Claassen, J.A.; Olde Rikkert, M.G.M.; Schalk, B.W.M; Meulenbroek, O.V.; Kessels, R.P.C.; Melis, R.J.F.

    2015-01-01

    BACKGROUND: patients suspected of dementia frequently undergo additional diagnostic testing (e.g. brain imaging or neuropsychological assessment) after standard clinical assessment at a memory clinic. This study investigates the use of additional testing in an academic outpatient memory clinic and

  1. [Sexual risk behaviours and PAP testing in university women vaccinated against human papillomavirus].

    Science.gov (United States)

    Fernández-Feito, Ana; Antón-Fernández, Raquel; Paz-Zulueta, María

    2018-05-01

    To estimate the association between the human papillomavirus (HPV) vaccine and sexual risk behaviour, as well as the participation in the Cervical Cancer Screening Program (CCSP). Cross-sectional study. School of Medicine and Health Sciences, School of Law, and School of Economics and Business (University of Oviedo). Female university students. Information was collected about contraceptive methods, sexual behaviours, HPV knowledge, and participation in the CCSP. Furthermore, proportions and odds ratio (OR) were estimated with their corresponding 95% confidence intervals (95%CI). Approximately two-thirds (67.7%) of the sample was vaccinated against HPV, and 216 women (65.3%) were sexually active. Barrier contraceptive methods were used by 67.6% during their current intimate relationships, being less frequent in non-vaccinated women (54.9% vs. 75.4% in vaccinated female students) (P=.002). The risk of having at least one sexual risk behaviour was higher in non-vaccinated women: OR2.29 (95%CI: 1.29-4.07). In addition, the probability of having a PAP test within the CCSP was higher in non-vaccinated women: OR2.18 (95%CI: 1.07-4.47). The prevalence of sexual risk behaviours in non-vaccinated women is elevated, and it is related to the lack of use of barrier contraceptive methods. The vaccination against HPV could affect sexual behaviours and the participation in the CCSP. Therefore, the information received by young people about contraceptive methods, sexually transmitted diseases, and cancer prevention should be reinforced. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  2. Conceptual similarity effects on working memory in sentence contexts: testing a theory of anaphora.

    Science.gov (United States)

    Cowles, H Wind; Garnham, Alan; Simner, Julia

    2010-06-01

    The degree of semantic similarity between an anaphoric noun phrase (e.g., the bird) and its antecedent (e.g., a robin) is known to affect the anaphor resolution process, but the mechanisms that underlie this effect are not known. One proposal (Almor, 1999) is that semantic similarity triggers interference effects in working memory and makes two crucial assumptions: First, semantic similarity impairs working memory just as phonological similarity does (e.g., Baddeley, 1992), and, second, this impairment interferes with processes of sentence comprehension. We tested these assumptions in two experiments that compared recall accuracy between phonologically similar, semantically similar, and control words in sentence contexts. Our results do not provide support for Almor's claims: Phonological overlap decreased recall accuracy in sentence contexts, but semantic similarity did not. These results shed doubt on the idea that semantic interference in working memory is an underlying mechanism in anaphor resolution.

  3. Memory evaluation in mild cognitive impairment using recall and recognition tests.

    Science.gov (United States)

    Bennett, Ilana J; Golob, Edward J; Parker, Elizabeth S; Starr, Arnold

    2006-11-01

    Amnestic mild cognitive impairment (MCI) is a selective episodic memory deficit that often indicates early Alzheimer's disease. Episodic memory function in MCI is typically defined by deficits in free recall, but can also be tested using recognition procedures. To assess both recall and recognition in MCI, MCI (n = 21) and older comparison (n = 30) groups completed the USC-Repeatable Episodic Memory Test. Subjects memorized two verbally presented 15-item lists. One list was used for three free recall trials, immediately followed by yes/no recognition. The second list was used for three-alternative forced-choice recognition. Relative to the comparison group, MCI had significantly fewer hits and more false alarms in yes/no recognition, and were less accurate in forced-choice recognition. Signal detection analysis showed that group differences were not due to response bias. Discriminant function analysis showed that yes/no recognition was a better predictor of group membership than free recall or forced-choice measures. MCI subjects recalled fewer items than comparison subjects, with no group differences in repetitions, intrusions, serial position effects, or measures of recall strategy (subjective organization, recall consistency). Performance deficits on free recall and recognition in MCI suggest a combination of both tests may be useful for defining episodic memory impairment associated with MCI and early Alzheimer's disease.

  4. Memory accessibility shapes explanation: Testing key claims of the inherence heuristic account.

    Science.gov (United States)

    Hussak, Larisa J; Cimpian, Andrei

    2018-01-01

    People understand the world by constructing explanations for what they observe. It is thus important to identify the cognitive processes underlying these judgments. According to a recent proposal, everyday explanations are often constructed heuristically: Because people need to generate explanations on a moment-by-moment basis, they cannot perform an exhaustive search through the space of possible reasons, but may instead use the information that is most easily accessible in memory (Cimpian & Salomon 2014a, b). In the present research, we tested two key claims of this proposal that have so far not been investigated. First, we tested whether-as previously hypothesized-the information about an entity that is most accessible in memory tends to consist of inherent or intrinsic facts about that entity, rather than extrinsic (contextual, historical, etc.) facts about it (Studies 1 and 2). Second, we tested the implications of this difference in the memory accessibility of inherent versus extrinsic facts for the process of generating explanations: Does the fact that inherent facts are more accessible than relevant extrinsic facts give rise to an inherence bias in the content of the explanations generated (Studies 3 and 4)? The findings supported the proposal that everyday explanations are generated in part via a heuristic process that relies on easily accessible-and often inherent-information from memory.

  5. SELF-ASSESSMENT, QUESTIONNAIRES AND MEMORY TESTS IN A SIMULATED DRIVING TASK

    OpenAIRE

    Combe-Pangaud , Chantal; Jacquet-Andrieu , Armelle

    2009-01-01

    disponible sur : http://www.chalmers.se/safer/driverdistraction-en; International audience; This paper concerns the results of a memorizing test (visual recognition and hearing recall) during an experiment of simulated driving in a magneto-encephalographic environment. The memory tests (questionnaires) are adapted to the measurement of subjective self-assessment: "tiredness" and "facility" perceptions, corralled to simple (ST) and double task (ST/DT: hearing a radio broadcast). Each subject h...

  6. Analysis of the X-ray microbeam test result of the flash memories

    International Nuclear Information System (INIS)

    Yan Yihua; Ding Lili; Chen Wei; Guo Hongxia; Guo Xiaoqiang; Lin Dongsheng; Zhang Keying; Zhang Fengqi; Deng Yuliang; Fan Ruyu

    2013-01-01

    Background: The failure phenomenon is difficult to analyze for the flash memories when the whole chip is exposed to irradiation since both the memory array and the peripheral circuits might be degraded. Purpose: In order to detect the radiation susceptibility and corresponding phenomenon of the related circuits that included in the flash memories, the X-ray microbeam is used as the radiation source instead of 60 Co. Methods: The failure phenomenon is studied respectively when the memory array, decoder circuits, the charge pump circuits as well as the I/O circuits are exposed to radiation. The errors are mapped according to the logical address and the failure mechanism is analyzed based on the circuits. Results: Irradiated on the memory .array win lead to regularly distributed 0→1 bit flips, while only 1→0 are found when the row decoder is under exposure. Degradation of the charge pump circuits would lead to the erase/program functional failure. Conclusions: The results suggest that the X-ray microbeam radiation test is a good method for detecting the radiation susceptibility of the integrated circuits that contains lots of circuit modules. (authors)

  7. Memory assessment and depression: testing for factor structure and measurement invariance of the Wechsler Memory Scale-Fourth Edition across a clinical and matched control sample.

    Science.gov (United States)

    Pauls, Franz; Petermann, Franz; Lepach, Anja Christina

    2013-01-01

    Between-group comparisons are permissible and meaningfully interpretable only if diagnostic instruments are proved to measure the same latent dimensions across different groups. Addressing this issue, the present study was carried out to provide a rigorous test of measurement invariance. Confirmatory factor analyses were used to determine which model solution could best explain memory performance as measured by the Wechsler Memory Scale-Fourth Edition (WMS-IV) in a clinical depression sample and in healthy controls. Multigroup confirmatory factor analysis was conducted to evaluate the evidence for measurement invariance. A three-factor model solution including the dimensions of auditory memory, visual memory, and visual working memory was identified to best fit the data in both samples, and measurement invariance was partially satisfied. The results supported clinical utility of the WMS-IV--that is, auditory and visual memory performances of patients with depressive disorders are interpretable on the basis of the WMS-IV standardization data. However, possible differences in visual working memory functions between healthy and depressed individuals could restrict comparisons of the WMS-IV working memory index.

  8. Containment aerosol behaviour simulation studies in the BARC nuclear aerosol test facility

    International Nuclear Information System (INIS)

    Mayya, Y.S.; Sapra, B.K.; Khan, Arshad; Sunny, Faby; Nair, R.N.; Raghunath, Radha; Tripathi, R.M.; Markandeya, S.G.; Puranik, V.D.; Ghosh, A.K.; Kushwaha, H.S.; Shreekumar, K.P.; Padmanabhan, P.V.A.; Murthy, P.S.S.; Venlataramani, N.

    2005-02-01

    A Nuclear Aerosol Test Facility (NATF) has been built and commissioned at Bhabha Atomic Research Centre to carry out simulation studies on the behaviour of aerosols released into the reactor containment under accident conditions. This report also discusses some new experimental techniques for estimation of density of metallic aggregates. The experimental studies have shown that the dynamic densities of aerosol aggregates are far lower than their material densities as expected by the well-known fractal theory of aggregates. In the context of codes, this has significant bearing in providing a mechanistic basis for the input density parameter used in estimating the aerosol evolution characteristics. The data generated under the quiescent and turbulent conditions and the information on aggregate densities are now being subjected to the validation of the aerosol behaviour codes. (author)

  9. Testicular Self-Examination: A Test of the Health Belief Model and the Theory of Planned Behaviour

    Science.gov (United States)

    McClenahan, Carol; Shevlin, Mark; Adamson, Gary; Bennett, Cara; O'Neill, Brenda

    2007-01-01

    The aim of this study was to test the utility and efficiency of the theory of planned behaviour (TPB) and the health belief model (HBM) in predicting testicular self-examination (TSE) behaviour. A questionnaire was administered to an opportunistic sample of 195 undergraduates aged 18-39 years. Structural equation modelling indicated that, on the…

  10. EPS Mid-Career Award 2011. Are there multiple memory systems? Tests of models of implicit and explicit memory.

    Science.gov (United States)

    Shanks, David R; Berry, Christopher J

    2012-01-01

    This article reviews recent work aimed at developing a new framework, based on signal detection theory, for understanding the relationship between explicit (e.g., recognition) and implicit (e.g., priming) memory. Within this framework, different assumptions about sources of memorial evidence can be framed. Application to experimental results provides robust evidence for a single-system model in preference to multiple-systems models. This evidence comes from several sources including studies of the effects of amnesia and ageing on explicit and implicit memory. The framework allows a range of concepts in current memory research, such as familiarity, recollection, fluency, and source memory, to be linked to implicit memory. More generally, this work emphasizes the value of modern computational modelling techniques in the study of learning and memory.

  11. Quality of education and memory test performance in older men: the New York University Paragraph Recall Test normative data.

    Science.gov (United States)

    Mathews, Melissa; Abner, Erin; Caban-Holt, Allison; Dennis, Brandon C; Kryscio, Richard; Schmitt, Frederick

    2013-09-01

    Memory evaluation is a key component in the accurate diagnosis of cognitive disorders.One memory procedure that has shown promise in discriminating disease-related cognitive decline from normal cognitive aging is the New York University Paragraph Recall Test; however, the effects of education have been unexamined as they pertain to one's literacy level. The current study provides normative data stratified by estimated quality of education as indexed by irregular word reading skill. Conventional norms were derived from a sample (N = 385) of cognitively intact elderly men who were initially recruited for participation in the PREADViSE clinical trial. A series of multiple linear regression models were constructed to assess the influence of demographic variables on mean NYU Paragraph Immediate and Delayed Recall scores. Test version, assessment site, and estimated quality of education were significant predictors of performance on the NYU Paragraph Recall Test. Findings indicate that estimated quality of education is a better predictor of memory performance than ethnicity and years of total education. Normative data stratified according to estimated quality of education are presented. The current study provides evidence and support for normativedata stratified by quality of education as opposed to years of education.

  12. Comparison of the Morel Emotional Numbing Test for Posttraumatic Stress Disorder to the Word Memory Test in neuropsychological evaluations.

    Science.gov (United States)

    Morel, Kenneth R

    2008-03-01

    The most commonly feigned cognitive and psychiatric disorders for survivors of traumatic injury are memory dysfunction and posttraumatic stress disorder (PTSD). The position of the National Academy of Neuropsychology is that symptom validity tests (SVTs) should be part of any comprehensive neuropsychological evaluation. In this article the Morel Emotional Numbing Test for Posttraumatic Stress Disorder (MENT), a SVT for PTSD, was compared to a SVT for memory, the Word Memory Test (WMT). Available archival data on 216 consecutive referrals for neuropsychological evaluations at the Veterans Affairs Tennessee Valley Healthcare System were reviewed. Of the total records reviewed 37 patients had been administered both the MENT and the WMT. The clinically recommended cutoff on the WMT was used as the main criterion to classify patients into two groups: simulating impairment or credible. The results indicated that the simulating impairment group had significantly more errors on the MENT than the credible group did (p <.0001). The criterion-related characteristics of the MENT in assessing response bias in relation to the WMT were confirmed Clinical and research implications of the utilization of the MENT are discussed in this study.

  13. Working memory and inhibitory control across the life span: Intrusion errors in the Reading Span Test.

    Science.gov (United States)

    Robert, Christelle; Borella, Erika; Fagot, Delphine; Lecerf, Thierry; de Ribaupierre, Anik

    2009-04-01

    The aim of this study was to examine to what extent inhibitory control and working memory capacity are related across the life span. Intrusion errors committed by children and younger and older adults were investigated in two versions of the Reading Span Test. In Experiment 1, a mixed Reading Span Test with items of various list lengths was administered. Older adults and children recalled fewer correct words and produced more intrusions than did young adults. Also, age-related differences were found in the type of intrusions committed. In Experiment 2, an adaptive Reading Span Test was administered, in which the list length of items was adapted to each individual's working memory capacity. Age groups differed neither on correct recall nor on the rate of intrusions, but they differed on the type of intrusions. Altogether, these findings indicate that the availability of attentional resources influences the efficiency of inhibition across the life span.

  14. Sensitivity and specificity of the 3-item memory test in the assessment of post traumatic amnesia.

    Science.gov (United States)

    Andriessen, Teuntje M J C; de Jong, Ben; Jacobs, Bram; van der Werf, Sieberen P; Vos, Pieter E

    2009-04-01

    To investigate how the type of stimulus (pictures or words) and the method of reproduction (free recall or recognition after a short or a long delay) affect the sensitivity and specificity of a 3-item memory test in the assessment of post traumatic amnesia (PTA). Daily testing was performed in 64 consecutively admitted traumatic brain injured patients, 22 orthopedically injured patients and 26 healthy controls until criteria for resolution of PTA were reached. Subjects were randomly assigned to a test with visual or verbal stimuli. Short delay reproduction was tested after an interval of 3-5 minutes, long delay reproduction was tested after 24 hours. Sensitivity and specificity were calculated over the first 4 test days. The 3-word test showed higher sensitivity than the 3-picture test, while specificity of the two tests was equally high. Free recall was a more effortful task than recognition for both patients and controls. In patients, a longer delay between registration and recall resulted in a significant decrease in the number of items reproduced. Presence of PTA is best assessed with a memory test that incorporates the free recall of words after a long delay.

  15. Effect of Ta Additions on the Microstructure, Damping, and Shape Memory Behaviour of Prealloyed Cu-Al-Ni Shape Memory Alloys

    Directory of Open Access Journals (Sweden)

    Safaa N. Saud

    2017-01-01

    Full Text Available The influence of Ta additions on the microstructure and properties of Cu-Al-Ni shape memory alloys was investigated in this paper. The addition of Ta significantly affects the green and porosity densities; the minimum percentage of porosity was observed with the modified prealloyed Cu-Al-Ni-2.0 wt.% Ta. The phase transformation temperatures were shifted towards the highest values after Ta was added. Based on the damping capacity results, the alloy of Cu-Al-Ni-3.0 wt.% Ta has very high internal friction with the maximum equivalent internal friction value twice as high as that of the prealloyed Cu-Al-Ni SMA. Moreover, the prealloyed Cu-Al-Ni SMAs with the addition of 2.0 wt.% Ta exhibited the highest shape recovery ratio in the first cycle (i.e., 100% recovery, and when the number of cycles is increased, this ratio tends to decrease. On the other hand, the modified alloys with 1.0 and 3.0 wt.% Ta implied a linear increment in the shape recovery ratio with increasing number of cycles. Polarization tests in NaCl solution showed that the corrosion resistance of Cu-Al-Ni-Ta SMA improved with escalating Ta concentration as shown by lower corrosion current densities, higher corrosion potential, and formation of stable passive film.

  16. Effect of Ta Additions on the Microstructure, Damping, and Shape Memory Behaviour of Prealloyed Cu-Al-Ni Shape Memory Alloys.

    Science.gov (United States)

    Saud, Safaa N; Hamzah, E; Bakhsheshi-Rad, H R; Abubakar, T

    2017-01-01

    The influence of Ta additions on the microstructure and properties of Cu-Al-Ni shape memory alloys was investigated in this paper. The addition of Ta significantly affects the green and porosity densities; the minimum percentage of porosity was observed with the modified prealloyed Cu-Al-Ni-2.0 wt.% Ta. The phase transformation temperatures were shifted towards the highest values after Ta was added. Based on the damping capacity results, the alloy of Cu-Al-Ni-3.0 wt.% Ta has very high internal friction with the maximum equivalent internal friction value twice as high as that of the prealloyed Cu-Al-Ni SMA. Moreover, the prealloyed Cu-Al-Ni SMAs with the addition of 2.0 wt.% Ta exhibited the highest shape recovery ratio in the first cycle (i.e., 100% recovery), and when the number of cycles is increased, this ratio tends to decrease. On the other hand, the modified alloys with 1.0 and 3.0 wt.% Ta implied a linear increment in the shape recovery ratio with increasing number of cycles. Polarization tests in NaCl solution showed that the corrosion resistance of Cu-Al-Ni-Ta SMA improved with escalating Ta concentration as shown by lower corrosion current densities, higher corrosion potential, and formation of stable passive film.

  17. Understanding Student Teachers’ Behavioural Intention to Use Technology: Technology Acceptance Model (TAM Validation and Testing

    Directory of Open Access Journals (Sweden)

    Kung-Teck, Wong

    2013-01-01

    Full Text Available This study sets out to validate and test the Technology Acceptance Model (TAM in the context of Malaysian student teachers’ integration of their technology in teaching and learning. To establish factorial validity, data collected from 302 respondents were tested against the TAM using confirmatory factor analysis (CFA, and structural equation modelling (SEM was used for model comparison and hypotheses testing. The goodness-of-fit test of the analysis shows partial support of the applicability of the TAM in a Malaysian context. Overall, the TAM accounted for 37.3% of the variance in intention to use technology among student teachers and of the five hypotheses formulated, four are supported. Perceived usefulness is a significant influence on attitude towards computer use and behavioural intention. Perceived ease of use significantly influences perceived usefulness, and finally, behavioural intention is found to be influenced by attitude towards computer use. The findings of this research contribute to the literature by validating the TAM in the Malaysian context and provide several prominent implications for the research and practice of technology integration development.

  18. Donepezil impairs memory in healthy older subjects: behavioural, EEG and simultaneous EEG/fMRI biomarkers.

    Directory of Open Access Journals (Sweden)

    Joshua H Balsters

    Full Text Available Rising life expectancies coupled with an increasing awareness of age-related cognitive decline have led to the unwarranted use of psychopharmaceuticals, including acetylcholinesterase inhibitors (AChEIs, by significant numbers of healthy older individuals. This trend has developed despite very limited data regarding the effectiveness of such drugs on non-clinical groups and recent work indicates that AChEIs can have negative cognitive effects in healthy populations. For the first time, we use a combination of EEG and simultaneous EEG/fMRI to examine the effects of a commonly prescribed AChEI (donepezil on cognition in healthy older participants. The short- and long-term impact of donepezil was assessed using two double-blind, placebo-controlled trials. In both cases, we utilised cognitive (paired associates learning (CPAL and electrophysiological measures (resting EEG power that have demonstrated high-sensitivity to age-related cognitive decline. Experiment 1 tested the effects of 5 mg/per day dosage on cognitive and EEG markers at 6-hour, 2-week and 4-week follow-ups. In experiment 2, the same markers were further scrutinised using simultaneous EEG/fMRI after a single 5 mg dose. Experiment 1 found significant negative effects of donepezil on CPAL and resting Alpha and Beta band power. Experiment 2 replicated these results and found additional drug-related increases in the Delta band. EEG/fMRI analyses revealed that these oscillatory differences were associated with activity differences in the left hippocampus (Delta, right frontal-parietal network (Alpha, and default-mode network (Beta. We demonstrate the utility of simple cognitive and EEG measures in evaluating drug responses after acute and chronic donepezil administration. The presentation of previously established markers of age-related cognitive decline indicates that AChEIs can impair cognitive function in healthy older individuals. To our knowledge this is the first study to identify

  19. Utility of finger maze test for learning and memory abilities in infants of cynomolgus monkeys exposed to thiamazole.

    Science.gov (United States)

    Inoue, Ayumi; Arima, Akihiro; Kato, Hirohito; Ebihara, Shizufumi

    2014-11-01

    A new type of learning and memory test using a finger maze was conducted in infant cynomolgus monkeys that were exposed to thiamazole (2 and 3.5 mg/kg per day to pregnant animals orally) during the fetal period (gestational days 120 to 150). We modified Tsuchida's original finger maze test method by reducing the number of trials per day and simplifying the criteria for achievement of training, and we added a long-term memory test. In the memory test, thiamazole-exposed infants required greater time to complete the finger maze test than the control infants although no effect was noted in the training or learning test. The results suggest that an impaired long-term memory could be detected by our modified finger maze test. © 2014 Japanese Teratology Society.

  20. Can education alter attitudes, behaviour and knowledge about organ donation? A pretest–post-test study

    Science.gov (United States)

    McGlade, Donal; Pierscionek, Barbara

    2013-01-01

    Objective The emergence of evidence suggests that student nurses commonly exhibit concerns about their lack of knowledge of organ donation and transplantation. Formal training about organ donation has been shown to positively influence attitude, encourage communication and registration behaviours and improve knowledge about donor eligibility and brain death. The focus of this study was to determine the attitude and behaviour of student nurses and to assess their level of knowledge about organ donation after a programme of study. Design A quantitative questionnaire was completed before and after participation in a programme of study using a pretest–post-test design. Setting Participants were recruited from a University based in Northern Ireland during the period from February to April 2011. Participants 100 preregistration nurses (female : male=96 : 4) aged 18–50 years (mean (SD) 24.3 (6.0) years) were recruited. Results Participants’ knowledge improved over the programme of study with regard to the suitability of organs that can be donated after death, methods available to register organ donation intentions, organ donation laws, concept of brain death and the likelihood of recovery after brain death. Changes in attitude postintervention were also observed in relation to participants’ willingness to accept an informed system of consent and with regard to participants’ actual discussion behaviour. Conclusions The results provide support for the introduction of a programme that helps inform student nurses about important aspects of organ donation. PMID:24381257

  1. Memory, Cognition and the Endogenous Evoked Potentials of the Brain: the Estimation of the Disturbance of Cognitive Functions and Capacity of Working Memory Without the Psychological Testing.

    Science.gov (United States)

    Gnezditskiy, V V; Korepina, O S; Chatskaya, A V; Klochkova, O I

    2017-01-01

    Cognition, cognitive and memory impairments is widely discussed in the literature, especially in the psycho physiological and the neurologic. In essence, this literature is dedicated to the psycho physiological tests, different scales. However, instrument neurophysiologic methods not so widely are used for these purposes. This review is dedicated to the instrument methods of neurophysiology, in particular to the endogenous evoked potentials method Р 300 (by characteristic latency 300 ms), in the estimation of cognitive functions and memory, to their special features dependent on age and to special features to their changes with the pathology. Method cognitive EP - Р 300 is the response of the brain, recorded under the conditions of the identification of the significant distinguishing stimulus, it facilitates the inspection of cognitive functions and memory in the healthy persons and patients with different manifestation of cognitive impairments. In the review it is shown on the basis of literature and our own data, that working (operative) memory and the capacity of the working memory it can be evaluated with the aid of the indices Р 300 within the normal subject and with the pathology. Testing with the estimation of working memory according to latent period of the peak Р 300 can be carried out and when conducting psychological testing is not possible for any reasons. Together with these cognitive EP are used for evidence pharmacotherapy of many neurotropic drugs.

  2. The role of novelty detection in food memory.

    Science.gov (United States)

    Morin-Audebrand, Léri; Mojet, Jos; Chabanet, Claire; Issanchou, Sylvie; Møller, Per; Köster, Ep; Sulmont-Rossé, Claire

    2012-01-01

    Memory plays a central role in food choice. Recent studies focusing on food memory in everyday eating and drinking behaviour used a paradigm based on incidental learning of target foods and unexpected memory testing, demanding recognition of the target among distractors, which deviate slightly from the target. Results question the traditional view of memory as reactivation of previous experiences. Comparison of data from several experiments shows that in incidentally learned memory, distractors are rejected, while original targets are not recognised better than by chance guessing. Food memory is tuned at detecting novelty and change, rather than at recognising a previously encountered food. Copyright © 2011. Published by Elsevier B.V.

  3. Herd behaviour experimental testing in laboratory artificial stock market settings. Behavioural foundations of stylised facts of financial returns

    Science.gov (United States)

    Manahov, Viktor; Hudson, Robert

    2013-10-01

    Many scholars express concerns that herding behaviour causes excess volatility, destabilises financial markets, and increases the likelihood of systemic risk. We use a special form of the Strongly Typed Genetic Programming (STGP) technique to evolve a stock market divided into two groups-a small subset of artificial agents called ‘Best Agents’ and a main cohort of agents named ‘All Agents’. The ‘Best Agents’ perform best in term of the trailing return of a wealth moving average. We then investigate whether herding behaviour can arise when agents trade Dow Jones, General Electric, and IBM financial instruments in four different artificial stock markets. This paper uses real historical quotes of the three financial instruments to analyse the behavioural foundations of stylised facts such as leptokurtosis, non-IIDness, and volatility clustering. We found evidence of more herding in a group of stocks than in individual stocks, but the magnitude of herding does not contribute to the mispricing of assets in the long run. Our findings suggest that the price formation process caused by the collective behaviour of the entire market exhibit less herding and is more efficient than the segmented market populated by a small subset of agents. Hence, greater genetic diversity leads to greater consistency with fundamental values and market efficiency.

  4. Anisotropic modelling of Opalinus Clay behaviour: From triaxial tests to gallery excavation application

    Directory of Open Access Journals (Sweden)

    François Bertrand

    2017-06-01

    Full Text Available Deep repository in geological formations is the preferential solution considered in many countries to manage high-level nuclear wastes. In Switzerland, the Opalinus Clay is a candidate host rock. In this context, in situ and laboratory tests are conducted on Opalinus Clay to demonstrate the feasibility of deep disposal in this argillaceous formation. This paper presents a constitutive model able to fit the experimental data obtained from some triaxial tests conducted by Jahns (2013 on cores from borehole Schlattingen SLA-1. The elasto-plastic behaviour of Opalinus Clay is reproduced thanks to a Drucker-Prager model, taking into account the anisotropy behaviour of this sedimentary rock. The objective is to employ a single set of parameters representative of the material. In a second version of the model, the stress-dependence of the elastic properties and damage are taken into account. Finally, the parameters calibrated with experimental tests are used to simulate the excavation of a gallery with a second gradient approach.

  5. Mechanical behaviour of the reactor vessel support of a pressurized water reactor: tests and analysis

    International Nuclear Information System (INIS)

    Bolvin, M.; L'huby, Y.; Quillico, J.J.; Humbert, J.M.; Thomas, J.P.; Hugenschmitt, R.

    1985-08-01

    The PWR reactor vessel is supported by a steel ring laying on the reactor pit. This support has to ensure a good behaviour of the vessel in the event of accidental conditions (earthquake and pipe rupture). A new evolution of the evaluation methods of the applied forces has shown a significant increase in the design loads used until now. In order to take into account these new forces, we carried out a test on a representative mock-up of the vessel support (scale 1/6). This test was performed by CEA, EDF and FRAMATOME. Several static equivalent forces were applied on the experimental mock-up. Displacements and strains were simultaneously recorded. The results of the test have enabled to justify the design of the pit and the ring, to show up a wide safety margin until the collapse of the structures and to check our hypothesis about the transmission of the forces between the ring and the pit

  6. Long term leaching of silicate systems: testing procedure, actinides behaviour and mechanism

    International Nuclear Information System (INIS)

    Louwrier, K.; Matzke, H.; Ray, I.; Thiele, H.; Scheffler, K.; Riege, U.

    1977-06-01

    High-level waste borosilicate glasses and medium-level waste cement products have been leached with various aqueous solutions at ambient temperature. The leach rates of americium and plutonium are determined as well as the behaviour of the actinides in the boundary surface glass/leachant and in the leachant itself. Methods like light-scattering photometry and differential refractometry, molecular filtration, scanning electron microscopy and α-spectrometry of the energy-loss of α-particles in thin layers have been applied. From the experimental results a general model for the leaching mechanism has been established. A critical review of leach test procedures is accomplished aiming at the improvement of common tests with respect to the extrapolation of the obtained leach test data to final disposal safety considerations. (orig.) [de

  7. The behaviour of the charging system of the Vivitron for the first voltage tests

    International Nuclear Information System (INIS)

    Helleboid, J.M.

    1992-06-01

    The charging system used for the initial commissioning of the Vivitron generator is a simplified temporary version of the final one. As the belt runs in a largely open structure performances could be possibly limited compared with the final design. The observed behaviour for the first high voltage tests was quite satisfying apart from the excessive parasitic currents at the rollers. That led us to study and test many solutions up to the point that a humidity level much higher than thought was discovered as the most probable cause of the problem. The further tests brought the confirmation as the parasitic currents at the supporting rollers not exceeded tens of microA under dry conditions as it had first been expected from the experimental design studies

  8. Use of the laboratory tests of soil modulus in modelling pile behaviour

    Science.gov (United States)

    Dyka, Ireneusz

    2012-10-01

    This article deals with the question of theoretical description of behaviour of a single pile rested in a layered soil medium. Particular attention is paid to soil modulus which is used in calculation method for pile load-settlement curve. A brief analysis of the results obtained by laboratory tests to assess soil modulus and its nonlinear variability has been presented. The results of tests have been used in triaxial apparatus and resonant column/torsional shear device. There have also been presented the results of load-settlement calculation for a single pile under axial load with implementation of different models of soil modulus degradation. On this basis, possibilities of using particular kinds of laboratory tests in calculation procedure of foundation settlement have been presented as well as further developments of them.

  9. The touchscreen operant platform for testing learning and memory in rats and mice

    Science.gov (United States)

    Horner, Alexa E.; Heath, Christopher J.; Hvoslef-Eide, Martha; Kent, Brianne A.; Kim, Chi Hun; Nilsson, Simon R. O.; Alsiö, Johan; Oomen, Charlotte A.; Holmes, Andrew; Saksida, Lisa M.; Bussey, Timothy J.

    2014-01-01

    Summary An increasingly popular method of assessing cognitive functions in rodents is the automated touchscreen platform, on which a number of different cognitive tests can be run in a manner very similar to touchscreen methods currently used to test human subjects. This methodology is low stress (using appetitive, rather than aversive reinforcement), has high translational potential, and lends itself to a high degree of standardisation and throughput. Applications include the study of cognition in rodent models of psychiatric and neurodegenerative diseases (e.g., Alzheimer’s disease, schizophrenia, Huntington’s disease, frontotemporal dementia), and characterisation of the role of select brain regions, neurotransmitter systems and genes in rodents. This protocol describes how to perform four touchscreen assays of learning and memory: Visual Discrimination, Object-Location Paired-Associates Learning, Visuomotor Conditional Learning and Autoshaping. It is accompanied by two further protocols using the touchscreen platform to assess executive function, working memory and pattern separation. PMID:24051959

  10. The touchscreen operant platform for testing learning and memory in rats and mice.

    Science.gov (United States)

    Horner, Alexa E; Heath, Christopher J; Hvoslef-Eide, Martha; Kent, Brianne A; Kim, Chi Hun; Nilsson, Simon R O; Alsiö, Johan; Oomen, Charlotte A; Holmes, Andrew; Saksida, Lisa M; Bussey, Timothy J

    2013-10-01

    An increasingly popular method of assessing cognitive functions in rodents is the automated touchscreen platform, on which a number of different cognitive tests can be run in a manner very similar to touchscreen methods currently used to test human subjects. This methodology is low stress (using appetitive rather than aversive reinforcement), has high translational potential and lends itself to a high degree of standardization and throughput. Applications include the study of cognition in rodent models of psychiatric and neurodegenerative diseases (e.g., Alzheimer's disease, schizophrenia, Huntington's disease, frontotemporal dementia), as well as the characterization of the role of select brain regions, neurotransmitter systems and genes in rodents. This protocol describes how to perform four touchscreen assays of learning and memory: visual discrimination, object-location paired-associates learning, visuomotor conditional learning and autoshaping. It is accompanied by two further protocols (also published in this issue) that use the touchscreen platform to assess executive function, working memory and pattern separation.

  11. An online study combining the constructs from the theory of planned behaviour and protection motivation theory in predicting intention to test for chlamydia in two testing contexts

    OpenAIRE

    Powell, R. L.; Pattison, H. M.; Francis, J.

    2016-01-01

    Chlamydia is a common sexually-transmitted infection that has potentially serious consequences unless detected and treated early. The health service in the UK offers clinic-based testing for chlamydia but uptake is low. Identifying the predictors of testing behaviours may inform interventions to increase uptake. Self-tests for chlamydia may facilitate testing and treatment in people who avoid clinic-based testing. Self-testing and being tested by a health care professional (HCP) involve two c...

  12. Diminishing-cues retrieval practice: A memory-enhancing technique that works when regular testing doesn't.

    Science.gov (United States)

    Fiechter, Joshua L; Benjamin, Aaron S

    2017-08-28

    Retrieval practice has been shown to be a highly effective tool for enhancing memory, a fact that has led to major changes to educational practice and technology. However, when initial learning is poor, initial retrieval practice is unlikely to be successful and long-term benefits of retrieval practice are compromised or nonexistent. Here, we investigate the benefit of a scaffolded retrieval technique called diminishing-cues retrieval practice (Finley, Benjamin, Hays, Bjork, & Kornell, Journal of Memory and Language, 64, 289-298, 2011). Under learning conditions that favored a strong testing effect, diminishing cues and standard retrieval practice both enhanced memory performance relative to restudy. Critically, under learning conditions where standard retrieval practice was not helpful, diminishing cues enhanced memory performance substantially. These experiments demonstrate that diminishing-cues retrieval practice can widen the range of conditions under which testing can benefit memory, and so can serve as a model for the broader application of testing-based techniques for enhancing learning.

  13. Word Memory Test Performance Across Cognitive Domains, Psychiatric Presentations, and Mild Traumatic Brain Injury.

    Science.gov (United States)

    Rowland, Jared A; Miskey, Holly M; Brearly, Timothy W; Martindale, Sarah L; Shura, Robert D

    2017-05-01

    The current study addressed two aims: (i) determine how Word Memory Test (WMT) performance relates to test performance across numerous cognitive domains and (ii) evaluate how current psychiatric disorders or mild traumatic brain injury (mTBI) history affects performance on the WMT after excluding participants with poor symptom validity. Participants were 235 Iraq and Afghanistan-era veterans (Mage = 35.5) who completed a comprehensive neuropsychological battery. Participants were divided into two groups based on WMT performance (Pass = 193, Fail = 42). Tests were grouped into cognitive domains and an average z-score was calculated for each domain. Significant differences were found between those who passed and those who failed the WMT on the memory, attention, executive function, and motor output domain z-scores. WMT failure was associated with a larger performance decrement in the memory domain than the sensation or visuospatial-construction domains. Participants with a current psychiatric diagnosis or mTBI history were significantly more likely to fail the WMT, even after removing participants with poor symptom validity. Results suggest that the WMT is most appropriate for assessing validity in the domains of attention, executive function, motor output and memory, with little relationship to performance in domains of sensation or visuospatial-construction. Comprehensive cognitive batteries would benefit from inclusion of additional performance validity tests in these domains. Additionally, symptom validity did not explain higher rates of WMT failure in individuals with a current psychiatric diagnosis or mTBI history. Further research is needed to better understand how these conditions may affect WMT performance. Published by Oxford University Press 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  14. Deconstructing the symbol digit modalities test in multiple sclerosis: The role of memory.

    Science.gov (United States)

    Patel, Viral P; Walker, Lisa A S; Feinstein, Anthony

    2017-10-01

    The Symbol Digit Modalities Test (SDMT) is a sensitive measure of impaired cognition in people with MS. While the SDMT is primarily considered a test of information processing speed, other components such as visual scanning and oral-motor ability have also been linked to performance. The objective of this study was to determine the role of memory in the performance of the SDMT. Two version of a modified computerized SDMT (c-SDMT) were employed, a fixed and a variable. For each group 50 MS and 33 healthy control (HC) participants were recruited. In the fixed c-SDMT, the symbol-digit code is kept constant for the entire test whereas in the variable version, it changes eight times. Unlike the traditional SDMT which records the correct number of responses, the c-SDMT presented here measures the mean response time (in seconds) for the eight trials. MS participants were slower than HC on the fixed (p < 0.001) and variable (p = 0.005) c-SDMT. Trend analysis showed performance improvement on the fixed, but not on the variable c-SDMT in both MS and HC groups. Furthermore, immediate visual memory recall was associated with the fixed (β = -0.299, p = 0.017), but not variable (B = -0.057, p = 0.260) c-SDMT. Immediate verbal memory was not associated with either versions of the c-SDMT. Given that the fixed and variable c-SDMTs are identical in every way apart from the fixity of the code, the ability of participants to speed up responses over the course of the fixed version only points to the contribution of incidental visual memory in test performance. Copyright © 2017. Published by Elsevier B.V.

  15. Memory for performance feedback :a test of three self- motivation theories

    OpenAIRE

    Donlin, Joanne Mac

    1990-01-01

    The current study tests the adequacy of three self-motive theories to predict recall of performance feedback, memory sensitivity, and ratings of perceived accuracy. Self-enhancement (Jones, 1973) predicts individuals are motivated to maintain their self-esteem. Individuals will therefore recall positive relative to negative feedback and will rate positive feedback as more accurate. Self-consistency theory (Swann, 1985) predicts individuals are motivated to maintain their self-conceptions. The...

  16. The six blind men and the elephant: Are episodic memory tasks tests of different things or different tests of the same thing?

    Science.gov (United States)

    Cheke, Lucy G; Clayton, Nicola S

    2015-09-01

    The development of episodic memory in children has been of interest to researchers for more than a century. Current behavioral tests that have been developed to assess episodic memory differ substantially in their surface features. Therefore, it is possible that these tests are assessing different memory processes. In this study, 106 children aged 3 to 6 years were tested on four putative tests of episodic memory. Covariation in performance was investigated in order to address two conflicting hypotheses: (a) that the high level of difference between the tests will result in little covariation in performance despite their being designed to assess the same ability and (b) that the conceptual similarity of these tasks will lead to high levels of covariation despite surface differences. The results indicated a gradual improvement with age on all tests. Performances on many of the tests were related, but not after controlling for age. A principal component analysis found that a single principal component was able to satisfactorily fit the observed data. This principal component produced a marginally stronger correlation with age than any test alone. As such, it might be concluded that different tests of episodic memory are too different to be used in parallel. Nevertheless, if used together, these tests may offer a robust assessment of episodic memory as a complex multifaceted process. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  17. The Effect of Retention Interval Task Difficulty on Young Children's Prospective Memory: Testing the Intention Monitoring Hypothesis

    Science.gov (United States)

    Mahy, Caitlin E. V.; Moses, Louis J.

    2015-01-01

    The current study examined the impact of retention interval task difficulty on 4- and 5-year-olds' prospective memory (PM) to test the hypothesis that children periodically monitor their intentions during the retention interval and that disrupting this monitoring may result in poorer PM performance. In addition, relations among PM, working memory,…

  18. Memory-impairing effects of local anesthetics in an elevated plus-maze test in mice

    Directory of Open Access Journals (Sweden)

    S.L. Blatt

    1998-04-01

    Full Text Available Post-training intracerebroventricular administration of procaine (20 µg/µl and dimethocaine (10 or 20 µg/µl, local anesthetics of the ester class, prolonged the latency (s in the retention test of male and female 3-month-old Swiss albino mice (25-35 g body weight; N = 140 in the elevated plus-maze (mean ± SEM for 10 male mice: control = 41.2 ± 8.1; procaine = 78.5 ± 10.3; 10 µg/µl dimethocaine = 58.7 ± 12.3; 20 µg/µl dimethocaine = 109.6 ± 5.73; for 10 female mice: control = 34.8 ± 5.8; procaine = 55.3 ± 13.4; 10 µg/µl dimethocaine = 59.9 ± 12.3 and 20 µg/µl dimethocaine = 61.3 ± 11.1. However, lidocaine (10 or 20 µg/µl, an amide class type of local anesthetic, failed to influence this parameter. Local anesthetics at the dose range used did not affect the motor coordination of mice exposed to the rota-rod test. These results suggest that procaine and dimethocaine impair some memory process(es in the plus-maze test. These findings are interpreted in terms of non-anesthetic mechanisms of action of these drugs on memory impairment and also confirm the validity of the elevated plus-maze for the evaluation of drugs affecting learning and memory in mice

  19. Test-retest reliability and practice effects of the Wechsler Memory Scale-III.

    Science.gov (United States)

    Lo, Ada H Y; Humphreys, Michael; Byrne, Gerard J; Pachana, Nancy A

    2012-09-01

    Although serial administration of cognitive tests is increasingly common, there is a paucity of research on test-retest reliabilities and practice effects, both of which are important for evaluating changes in functioning. Reliability is generally conceptualized as involving short-lasting changes in performance. However, when repeated testing occurs over a period of years, there will be some longer lasting effects. The implications of these longer lasting effects and practice effects on reliability were examined in the context of repeated administrations of the Wechsler Memory Scale-III in 339 community-dwelling women aged 40-79 years over 2 to 7 years. The results showed that Logical Memory and Verbal Paired Associates subtests were consistently the most reliable subtests across the age cohorts. The magnitude of practice effects varied as a function of subtests and age. The largest practice effects were found in the youngest age cohort, especially on the Faces, Logical Memory, and Verbal Paired Associates subtests. ©2012 The British Psychological Society.

  20. Initial phase of adaptation of Memory Alteration Test (M@T) in a Portuguese sample.

    Science.gov (United States)

    Sousa, Mónica; Pereira, Anabela; Costa, Rui; Rami, Lorena

    2015-01-01

    The Memory Alteration Test is a screening test able to discriminate the amnestic mild cognitive impairment (A-MCI) and mild Alzheimer disease from subjective memory complain group (SMC-G). The aim of this study was to analyze the European Portuguese experimental version of the Memory Alteration Test (M@T-PT). Were described the successive stages of the translation and adaptation procedure used to develop the M@T-PT. The psychometric properties were explored using principal component analysis (PCA) with varimax rotation, internal consistence, convergent validity and receiver operating characteristics (ROC) curves. Chi-squared, ANOVAs and Pearson's correlation were also analyzed. A total of 330 people with an age greater or equal to 54 years old participated. According to their cognitive state they were classified as normal controls (n=28), SMC-G (n=81) or A-MCI (n=221). The PCA for the M@T-PT indicated that the total variance explained by three components was 48.07%. A high internal consistent was obtained (α=0.93). Convergent validity was verified using M@T-PT and Mini-Mental State Examination (r=0.83, psound instrument for use in older people in Portugal. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Absolute pitch memory: its prevalence among musicians and dependence on the testing context.

    Science.gov (United States)

    Wong, Yetta Kwailing; Wong, Alan C-N

    2014-04-01

    Absolute pitch (AP) is widely believed to be a rare ability possessed by only a small group of gifted and special individuals (AP possessors). While AP has fascinated psychologists, neuroscientists, and musicians for more than a century, no theory can satisfactorily explain why this ability is so rare and difficult to learn. Here, we show that AP ability appears rare because of the methodological issues of the standard pitch-naming test. Specifically, the standard test unnecessarily poses a high decisional demand on AP judgments and uses a testing context that is highly inconsistent with one's musical training. These extra cognitive challenges are not central to AP memory per se and have thus led to consistent underestimation of AP ability in the population. Using the standard test, we replicated the typical findings that the accuracy for general violinists was low (12.38 %; chance level = 0 %). With identical stimuli, scoring criteria, and participants, violinists attained 25 % accuracy in a pitch verification test in which the decisional demand of AP judgment was reduced. When the testing context was increasingly similar to their musical experience, verification accuracy improved further and reached 39 %, three times higher than that for the standard test. Results were replicated with a separate group of pianists. Our findings challenge current theories about AP and suggest that the prevalence of AP among musicians has been highly underestimated in prior work. A multimodal framework is proposed to better explain AP memory.

  2. Device Design and Test of Fatigue Behaviour of Expansion Anchor Subjected to Tensile Loads

    Directory of Open Access Journals (Sweden)

    Zhang Jinfeng

    2016-01-01

    Full Text Available In order to study on the fatigue behaviour of expansion anchor (M16, grade 8.8 for overhead contact system in electrification railways, a set of safe, practical loading device is designed and a fatigue test campaign was carried out at structural laboratory of China Academy of Building Research on expansion anchor embedded in concrete block. The mobile frame of the loading device was designed well by finite-element simulation. According to some fatigue performance test of expansion anchor with different size and form, the device have been assessed experimentally its dependability. The results were found that no fatigue damage phenomenon occurred in all specimens after 2×106 cycles tensile fatigue test in this specific series. It shows that in the condition of medium level or slightly lower maximum stress limit and nominal stress range, expansion bolt has good fatigue resistance. The biggest relative displacement and the residual relative displacement after test (Δδ = δ2-δ1 was also strongly lower than the symbol of the fatigue test failure index of this specific series (0.5mm in the high cycle fatigue regime. The ultimate tension failures mode after fatigue tests in all tested samples take place in the concrete anchorage zone. The reduction range of the ultimate tensile strength properties of the anchorage system was not obvious, and the concrete was seen to be the weakest link of the system.

  3. Comparison of the burning behaviour of electric cables with intumescent coating in different test methods

    International Nuclear Information System (INIS)

    Will, J.; Hosser, D.

    2000-01-01

    Cables used for electric power and control systems represent a significant potential hazard, particularly in buildings with highly complex wiring. To reduce the risk of ignition and of flame spread and to limit the fire effects, protective intumescent coatings or cables with fire retardant insulation materials have been implemented in safety related areas and locations, particularly of nuclear power plants. Since 1994, extensive experimental research has been performed by iBMB of the Branschweig University of Technology on the burning behaviour of unprotected as well as coated PVC cables. The main goal of this investigations was to develop a qualification method and licensing procedure for cable systems with protective coatings based on realistic fire conditions, which is accepted by the building authorities for application in buildings in general and, in particular, in nuclear power plants. For comparative results of tests with intumescent coatings in different scales - according to the standard IEC 332-3 (large scale), German standard DIN 4102-1 (intermediate scale) and ISO 5660 (small scale) - will be introduced. The setup of the different test procedures and the corresponding phases of natural fires will be discussed. It will be shown that cables with protective coatings are appropriate for fire scenarios up to a developed room fire while only resistance to a local ignition source could be guaranteed by testing according to international or national valid standard. The necessity of testing cables with insulation material, which should guarantee a fire retardant behaviour, by these different methods should be reasonable, because depending on the results of future tests, a more distinguished qualification and application of cables might be possible. (orig.) [de

  4. Anisotropic Behaviour of Opalinus Clay Through Consolidated and Drained Triaxial Testing in Saturated Conditions

    Science.gov (United States)

    Favero, Valentina; Ferrari, Alessio; Laloui, Lyesse

    2018-05-01

    This paper investigates the anisotropic hydro-mechanical behaviour of Opalinus Clay shale, the host material currently being considered for the construction of a nuclear waste repository in Switzerland. Consolidated and drained triaxial tests on Opalinus Clay from the Mont Terri URL have been conducted in order to derive information on its strength and stiffness properties. Opalinus Clay specimens were tested both parallel to bedding (P-specimens) and perpendicular to bedding (S-specimens). The considered effective confining stress range (from 2 to 12 MPa) has been selected in order to reproduce possible in situ stress conditions for the repository. In this work, particular attention has been paid to the experimental procedure in order to ensure consolidated conditions and avoid generation of unwanted excess pore water pressure during drained shearing. The Skempton B parameter has been determined for all the tested specimens in order to ensure saturation. Both single-stage and multistage triaxial testing procedures were adopted in the experimental campaign. The results of the triaxial tests highlight an anisotropic elastic response of Opalinus Clay: S-specimens present a more compliant behaviour than P-specimens. The values of the Young modulus are found to increase with the increase in mean effective stress. The analysis of the peak and ultimate shear strength results reveals that the material behaves in a similar manner regardless of the considered direction of loading (P and S directions) with respect to the bedding orientation. Peak and ultimate failure envelopes for Opalinus Clay were derived for the investigated stress range.

  5. MK-801 and memantine act differently on short-term memory tested with different time-intervals in the Morris water maze test.

    Science.gov (United States)

    Duda, Weronika; Wesierska, Malgorzata; Ostaszewski, Pawel; Vales, Karel; Nekovarova, Tereza; Stuchlik, Ales

    2016-09-15

    N-methyl-d-aspartate receptors (NMDARs) play a crucial role in spatial memory formation. In neuropharmacological studies their functioning strongly depends on testing conditions and the dosage of NMDAR antagonists. The aim of this study was to assess the immediate effects of NMDAR block by (+)MK-801 or memantine on short-term allothetic memory. Memory was tested in a working memory version of the Morris water maze test. In our version of the test, rats underwent one day of training with 8 trials, and then three experimental days when rats were injected intraperitoneally with low- 5 (MeL), high - 20 (MeH) mg/kg memantine, 0.1mg/kg MK-801 or 1ml/kg saline (SAL) 30min before testing, for three consecutive days. On each experimental day there was just one acquisition and one test trial, with an inter-trial interval of 5 or 15min. During training the hidden platform was relocated after each trial and during the experiment after each day. The follow-up effect was assessed on day 9. Intact rats improved their spatial memory across the one training day. With a 5min interval MeH rats had longer latency then all rats during retrieval. With a 15min interval the MeH rats presented worse working memory measured as retrieval minus acquisition trial for path than SAL and MeL and for latency than MeL rats. MK-801 rats had longer latency than SAL during retrieval. Thus, the high dose of memantine, contrary to low dose of MK-801 disrupts short-term memory independent on the time interval between acquisition and retrieval. This shows that short-term memory tested in a working memory version of water maze is sensitive to several parameters: i.e., NMDA receptor antagonist type, dosage and the time interval between learning and testing. Copyright © 2016. Published by Elsevier B.V.

  6. Using the Rosenzweig frustration picture test in the study of coping behaviour in thesituation of uncertainty

    Directory of Open Access Journals (Sweden)

    Elena N. L’vova

    2016-03-01

    Full Text Available The paper highlights the relation between the relevance of coping behaviour and increasing interest to phenomena of uncertainty. The reviewing of coping as complicated setting notion including several levels is offered. The relevance of studying conscious and unconscious levels of coping is validated. Using coping questionnaires’ deficit of prognosis validity and the relevancy of using projective methods that are effective and useful in diagnostics of coping’ unconscious components are discussed. Due to the changes in viewing difficult life situations’ range and focusing on subjective perception of difficulties, the frustration situations are reviewed as difficult daily life situations. The Rosenzweig Picture Frustration test could be used for diagnosing coping’ unconscious components that compose meaning set level and coping behaviour basis. The relations among personal characteristics (tolerance/intolerance to uncertainty, noetic orientations, personal anxiety, locus of control and three types and three directions of subjects’ responses in test’ situations were examined, generalized linear models were used. The subjects of the research are 199 teachers from secondary schools of Russian Federation, mean age is 40.6 years old. The results showed significant relations between particular personal characteristics and types and directions of the responses: ego-defense type and tolerance to uncertainty, obstacle-dominance type and personal anxiety, intropunitive direction and personal anxiety, obstacledominance type and noetic orientations. The common discussion of current results and results obtained in previous studies demonstrates potential existence of mediating relations between particular coping strategies and types and directions of subjects’ responses in The Rosenzweig Picture Frustration test.

  7. Texture development and anisotropic behaviour of a TI-44.2NI4.9CU (AT.%) shape memory alloy

    NARCIS (Netherlands)

    Zhao, L.

    1997-01-01

    The objective of this work was to determine the relationship between texture development and anisotropy of shape memory properties. A commercial Ti-45Ni-5Cu (at.%) shape memory alloy was selected. Textures were developed by controlling rolling parameters, such as rolling temperature, intermediate

  8. Partial and specific source memory for faces associated to other- and self-relevant negative contexts.

    Science.gov (United States)

    Bell, Raoul; Giang, Trang; Buchner, Axel

    2012-01-01

    Previous research has shown a source memory advantage for faces presented in negative contexts. As yet it remains unclear whether participants remember the specific type of context in which the faces were presented or whether they can only remember that the face was associated with negative valence. In the present study, participants saw faces together with descriptions of two different types of negative behaviour and neutral behaviour. In Experiment 1, we examined whether the participants were able to discriminate between two types of other-relevant negative context information (cheating and disgusting behaviour) in a source memory test. In Experiment 2, we assessed source memory for other-relevant negative (threatening) context information (other-aggressive behaviour) and self-relevant negative context information (self-aggressive behaviour). A multinomial source memory model was used to separately assess partial source memory for the negative valence of the behaviour and specific source memory for the particular type of negative context the face was associated with. In Experiment 1, source memory was specific for the particular type of negative context presented (i.e., cheating or disgusting behaviour). Experiment 2 showed that source memory for other-relevant negative information was more specific than source memory for self-relevant information. Thus, emotional source memory may vary in specificity depending on the degree to which the negative emotional context is perceived as threatening.

  9. Tourette's Syndrome: Performance on Tests of Behavioural Inhibition, Working Memory and Gambling

    Science.gov (United States)

    Crawford, Sarah; Channon, Shelley; Robertson, Mary M.

    2005-01-01

    Background: Tourette's syndrome (TS) is a neurodevelopmental disorder associated with fronto-striatal dysfunction. There is debate as to the extent to which TS is associated with cognitive impairment. Some authors argue that any impairments seen are attributable to comorbid psychiatric symptomatology, whilst others have suggested that…

  10. The behaviour of a vehicle’s suspension system on dynamic testing conditions

    Science.gov (United States)

    Mihon, L.; Lontiş, N.; Deac, S.

    2018-01-01

    The paper presents a car suspension’s behaviour on dynamic testing conditions through theoretical and mathematical simulation on specific model, on the single traction wheel, according to the real vehicle and by experiment on the test bench by reproducing the road’s geometry and vehicle’s speed and measuring the acceleration and damping response of the suspension system on that wheel. There are taking in consideration also the geometry and properties of the tyre-wheel model and physical wheel’s properties. The results are important due to the suspension’s model properties which allows to extend the theory and applications to the whole vehicle for improving the vehicle’s dynamics.

  11. Modelling the nonlinear behaviour of an underplatform damper test rig for turbine applications

    Science.gov (United States)

    Pesaresi, L.; Salles, L.; Jones, A.; Green, J. S.; Schwingshackl, C. W.

    2017-02-01

    Underplatform dampers (UPD) are commonly used in aircraft engines to mitigate the risk of high-cycle fatigue failure of turbine blades. The energy dissipated at the friction contact interface of the damper reduces the vibration amplitude significantly, and the couplings of the blades can also lead to significant shifts of the resonance frequencies of the bladed disk. The highly nonlinear behaviour of bladed discs constrained by UPDs requires an advanced modelling approach to ensure that the correct damper geometry is selected during the design of the turbine, and that no unexpected resonance frequencies and amplitudes will occur in operation. Approaches based on an explicit model of the damper in combination with multi-harmonic balance solvers have emerged as a promising way to predict the nonlinear behaviour of UPDs correctly, however rigorous experimental validations are required before approaches of this type can be used with confidence. In this study, a nonlinear analysis based on an updated explicit damper model having different levels of detail is performed, and the results are evaluated against a newly-developed UPD test rig. Detailed linear finite element models are used as input for the nonlinear analysis, allowing the inclusion of damper flexibility and inertia effects. The nonlinear friction interface between the blades and the damper is described with a dense grid of 3D friction contact elements which allow accurate capturing of the underlying nonlinear mechanism that drives the global nonlinear behaviour. The introduced explicit damper model showed a great dependence on the correct contact pressure distribution. The use of an accurate, measurement based, distribution, better matched the nonlinear dynamic behaviour of the test rig. Good agreement with the measured frequency response data could only be reached when the zero harmonic term (constant term) was included in the multi-harmonic expansion of the nonlinear problem, highlighting its importance

  12. Memory testing with Saturne synchrotron beams. Experiments with protons and deuterons

    International Nuclear Information System (INIS)

    Buisson, J.

    1989-01-01

    For simulate light ions of the cosmic rays CEA will use facilities used in fundamental physic research. SATURNE is a synchrotron especially designed to accelerate light particles, for example protons with energy up to 2.9 GeV. Two experiments are made on SATURNE to specify the beam characteristics (energy and intensity) and to adapt the beam for irradiation of electronic components. During these preliminary experimentation memories and microprocessors was tested. The results of the tests (cross-section) are given in this paper [fr

  13. The manufacture of system for testing static random access memory radiation effect

    International Nuclear Information System (INIS)

    Chen Rui; Yang Chen

    2008-01-01

    Space radiation effects will lead to single event upset, event latch up and other phenomena in SRAM devices. This paper introduces the hardware, software composition and related testing technology of SRAM radiation effect testing device. Through to the SRAM chip current detection and power protection, it has solved the SRAM chip damage question in the SRAM experiment. It has accessed to the expected experimental data by using the device in different source of radiation conducted on SRAM Experimental study of radiation effects. It provides important references in the assessment of operational life and reinforcement of the memory carried in the satellites. (authors)

  14. Word Memory Test Predicts Recovery in Claimants With Work-Related Head Injury.

    Science.gov (United States)

    Colangelo, Annette; Abada, Abigail; Haws, Calvin; Park, Joanne; Niemeläinen, Riikka; Gross, Douglas P

    2016-05-01

    To investigate the predictive validity of the Word Memory Test (WMT), a verbal memory neuropsychological test developed as a performance validity measure to assess memory, effort, and performance consistency. Cohort study with 1-year follow-up. Workers' compensation rehabilitation facility. Participants included workers' compensation claimants with work-related head injury (N=188; mean age, 44y; 161 men [85.6%]). Not applicable. Outcome measures for determining predictive validity included days to suspension of wage replacement benefits during the 1-year follow-up and work status at discharge in claimants undergoing rehabilitation. Analysis included multivariable Cox and logistic regression. Better WMT performance was significantly but weakly correlated with younger age (r=-.30), documented brain abnormality (r=.28), and loss of consciousness at the time of injury (r=.25). Claimants with documented brain abnormalities on diagnostic imaging scans performed better (∼9%) on the WMT than those without brain abnormalities. The WMT predicted days receiving benefits (adjusted hazard ratio, 1.13; 95% confidence interval, 1.04-1.24) and work status outcome at program discharge (adjusted odds ratio, 1.62; 95% confidence interval, 1.13-2.34). Our results provide evidence for the predictive validity of the WMT in workers' compensation claimants. Younger claimants and those with more severe brain injuries performed better on the WMT. It may be that financial incentives or other factors related to the compensation claim affected the performance. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  15. Effects of stress on memory in children and adolescents: testing causal connections.

    Science.gov (United States)

    Quas, Jodi A; Rush, Elizabeth B; Yim, Ilona S; Nikolayev, Mariya

    2014-01-01

    Although a sizeable body of research has examined children's memory for stressful prior experiences, relatively few studies have experimentally manipulated stress during a to-be-remembered event to draw causal inferences about the effects of stress, especially across wide age ranges. We exposed children and adolescents to a more or a less arousing version of the Trier Social Stress Test-Modified (TSST-M), a widely used laboratory stress task. Two weeks later, we tested their memory for what happened. Interviewers behaved in a supportive or non-supportive manner. In adolescents, those who completed the high-arousal TSST-M provided fewer correct responses to recognition questions and fewer incorrect responses to misleading questions for which any answer would have been incorrect, compared to those who completed the lower-arousal TSST-M. Thus, arousal seemed to have reduced the adolescents' willingness to answer questions rather than having influenced their memory per se. In children, across TSST-M conditions, greater physiological arousal during the TSST-M predicted enhanced recall. Finally, interviewer support reduced the amount of factual information provided in free recall but increased correct responses to misleading questions. Results highlight the complex ways in which event stress and interviewer demeanour shape recounting of prior experiences across development.

  16. A Systematic Review of Genetic Testing and Lifestyle Behaviour Change: Are We Using High-Quality Genetic Interventions and Considering Behaviour Change Theory?

    Science.gov (United States)

    Horne, Justine; Madill, Janet; O'Connor, Colleen; Shelley, Jacob; Gilliland, Jason

    2018-04-10

    Studying the impact of genetic testing interventions on lifestyle behaviour change has been a priority area of research in recent years. Substantial heterogeneity exists in the results and conclusions of this literature, which has yet to be explained using validated behaviour change theory and an assessment of the quality of genetic interventions. The theory of planned behaviour (TPB) helps to explain key contributors to behaviour change. It has been hypothesized that personalization could be added to this theory to help predict changes in health behaviours. This systematic review provides a detailed, comprehensive identification, assessment, and summary of primary research articles pertaining to lifestyle behaviour change (nutrition, physical activity, sleep, and smoking) resulting from genetic testing interventions. The present review further aims to provide in-depth analyses of studies conducted to date within the context of the TPB and the quality of genetic interventions provided to participants while aiming to determine whether or not genetic testing facilitates changes in lifestyle habits. This review is timely in light of a recently published "call-to-action" paper, highlighting the need to incorporate the TPB into personalized healthcare behaviour change research. Three bibliographic databases, one key website, and article reference lists were searched for relevant primary research articles. The PRISMA Flow Diagram and PRISMA Checklist were used to guide the search strategy and manuscript preparation. Out of 32,783 titles retrieved, 26 studies met the inclusion criteria. Three quality assessments were conducted and included: (1) risk of bias, (2) quality of genetic interventions, and (3) consideration of theoretical underpinnings - primarily the TPB. Risk of bias in studies was overall rated to be "fair." Consideration of the TPB was "poor," with no study making reference to this validated theory. While some studies (n = 11; 42%) made reference to other

  17. Almeria spatial memory recognition test (ASMRT): Gender differences emerged in a new passive spatial task.

    Science.gov (United States)

    Tascón, Laura; García-Moreno, Luis Miguel; Cimadevilla, Jose Manuel

    2017-06-09

    Many different human spatial memory tasks were developed in the last two decades. Virtual reality based tasks make possible developing different scenarios and situations to assess spatial orientation but sometimes these tasks are complex for specific populations like children and older-adults. A new spatial task with a very limited technological requirement was developed in this study. It demanded the use of spatial memory for an accurate solution. It also proved to be sensitive to gender differences, with men outperforming women under high specific difficulty levels. Thanks to its simplicity it could be applied as a screening test and is easy to combine with EEG and fMRI studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. The effects of repeat testing, malingering, and traumatic brain injury on visuospatial memory span

    Directory of Open Access Journals (Sweden)

    David L Woods

    2016-01-01

    Full Text Available Spatial span tests such as the Corsi Block Test (CBT and the spatial span test of the Wechsler Memory Scale are widely used to assess deficits in spatial working memory. We conducted three experiments to evaluate the test-retest reliability and clinical sensitivity of a new computerized spatial span test (C-SST that incorporates psychophysical methods to improve the precision of spatial span measurement. In Experiment 1, we analyzed C-SST test-retest reliability in 49 participants who underwent three test sessions at weekly intervals. Intraclass correlation coefficients (ICC were higher for a psychophysically derived mean span (MnS metric (0.83 than for the maximal span and total correct metrics used in traditional spatial-span tests. Response times (ReTs also showed high ICCs (0.93 that correlated negatively with MnS scores and correlated positively with response-time latencies from other tests of processing speed. Learning effects were insignificant. Experiment 2 examined the performance of Experiment 1 participants when instructed to feign symptoms of traumatic brain injury: 57% showed abnormal MnS z-scores. A MnS z-score cutoff of 3.0 correctly classified 36% of simulated malingerers and 91% of the subgroup of 11 control participants with abnormal spans. Malingerers also made more substitution errors than control participants with abnormal spans (sensitivity = 43%, specificity = 91%. In addition, malingerers showed no evidence of ReT slowing, in contrast to significant abnormalities seen on other malingered tests of processing speed. As a result, differences between ReT z-scores and z-scores on other processing speed tests showed very high sensitivity and specificity in distinguishing malingering and control participants with either normal or abnormal spans. Experiment 3 examined C-SST performance in a group of patients with predominantly mild traumatic brain injury (TBI: neither MnS nor ReT z-scores showed significant group

  19. Clinical utility of auditory memory testing in a heart failure population.

    Science.gov (United States)

    Hammers, Dustin B; Jung, Miyeon; Pressler, Susan J; Sullivan, Barbara-Jean; Koelling, Todd; Giordani, Bruno

    2013-01-01

    The self-care regimen necessary in heart failure (HF) is notably complex. A complication to integrating new knowledge and behaviors is that impaired cognition has been frequently reported in patients with HF, which significantly impacts patients' health, admission and mortality rates, and instrumental activities of daily living. The identification of reliable cognitive screening tools to assess potential difficulties in performing self-care for cardiac populations is essential. As such, the current purposes were to evaluate the validity and stability of the International Shopping List (ISL) auditory learning subtest from the computerized CogState battery as a screening tool in HF populations, determine the ISL's ability to predict functional declines, and evaluate the task's sensitivity in myocardial infarction. Forty patients with chronic HF were enrolled in a longitudinal study evaluating the impact of a cognitive training intervention. Baseline neuropsychological and behavioral measurements before treatment were used in the current study, including measures of auditory memory, orientation, verbal fluency, processing speed, and activities of daily living, and a subset of patients (n = 17) received repeat testing at 8 weeks on some tasks. Analyses also were performed with patients organized based on myocardial infarction status. The current study indicated that the ISL performed comparably with an established measure of auditory memory (Hopkins Verbal Learning Test-Revised; r = 0.70, P auditory memory subtest, the ISL, seems to be a beneficial tool in evaluating cognitive change in HF patients. Particularly given its cross-cultural sensitivity and ease of administration and scoring, this task may provide assistance to quickly and reliably monitor memory functioning in these vulnerable patients and gauge their potential for self-care behaviors.

  20. Caffeine reversal of ethanol effects on the multiple sleep latency test, memory, and psychomotor performance.

    Science.gov (United States)

    Drake, Christopher L; Roehrs, Timothy; Turner, Lauren; Scofield, Holly M; Roth, Thomas

    2003-02-01

    Caffeine has been shown to reverse some of the performance-impairing effects of ethanol. However, it is not known whether this antagonistic effect of caffeine is mediated by a reduction in sleepiness. The present study assessed physiological alertness/sleepiness, memory, and psychomotor performance following the administration of placebo, ethanol, and caffeine+ethanol combinations. A total of 13 healthy individuals (21-35 years old) underwent four conditions presented in a Latin Square Design: placebo-placebo, ethanol (0.5 g/kg)-placebo, ethanol (0.5 g/kg)-caffeine 150 mg, and ethanol (0.5 g/kg)-caffeine 300-mg. The Multiple Sleep Latency Test (MSLT), psychomotor performance battery, memory test, and mood/sleepiness questionnaires were administered following each condition. The peak breadth ethanol concentration (BrEC) was 0.043+/-0.0197% and did not differ among the three caffeine treatments. As expected, ethanol reduced mean latency on the MSLT. The lowest caffeine dose reversed this effect and the highest dose increased mean latency (greater alertness) significantly beyond placebo levels. Ethanol also impaired psychomotor performance and memory. The 300-mg caffeine dose restored performance and memory measures to placebo levels. Although visual analog ratings of dizziness were increased by ethanol, they were not diminished by either caffeine dose. In conclusion, Low-dose caffeine prevented the sleepiness and performance impairment associated with a moderate dose of ethanol. Thus, caffeine, similar to other stimulants, can reverse the physiologically sedating effects of ethanol, although other negative effects remain.

  1. Effects of Repeated Testing on Short- and Long-Term Memory Performance across Different Test Formats

    Science.gov (United States)

    Stenlund, Tova; Sundström, Anna; Jonsson, Bert

    2016-01-01

    This study examined whether practice testing with short-answer (SA) items benefits learning over time compared to practice testing with multiple-choice (MC) items, and rereading the material. More specifically, the aim was to test the hypotheses of "retrieval effort" and "transfer appropriate processing" by comparing retention…

  2. Additive and Multiplicative Effects of Working Memory and Test Anxiety on Mathematics Performance in Grade 3 Students

    Science.gov (United States)

    Korhonen, Johan; Nyroos, Mikaela; Jonsson, Bert; Eklöf, Hanna

    2018-01-01

    The aim of this study was to investigate the interplay between test anxiety and working memory (WM) on mathematics performance in younger children. A sample of 624 grade 3 students completed a test battery consisting of a test anxiety scale, WM tasks and the Swedish national examination in mathematics for grade 3. The main effects of test anxiety…

  3. Testing the mate-choice hypothesis of the female orgasm: disentangling traits and behaviours.

    Science.gov (United States)

    Sherlock, James M; Sidari, Morgan J; Harris, Emily Ann; Barlow, Fiona Kate; Zietsch, Brendan P

    2016-01-01

    The evolution of the female orgasm in humans and its role in romantic relationships is poorly understood. Whereas the male orgasm is inherently linked to reproduction, the female orgasm is not linked to obvious reproductive or survival benefits. It also occurs less consistently during penetrative sex than does the male orgasm. Mate-choice hypotheses posit that the wide variation in female orgasm frequency reflects a discriminatory mechanism designed to select high-quality mates. We aimed to determine (1) whether women report that their orgasm frequency varies between partners, (2) whether this variation reflects mates' personal characteristics, and (3) whether this variation reflects own and partner sexual behaviour during intercourse. We collected survey data from 103 women who rated (1) the extent to which their orgasm frequency varied between partners, (2) the characteristics of previous sexual partners who induced high-orgasm frequency and those who induced low-orgasm frequency, and (3) the specific behaviours during sex with those partners. This is the first study to test within-woman variation in orgasm and partner traits. Overall, women reported variation in their orgasm rates with different partners. Partners who induced high-orgasm rates were rated as more humorous, creative, warm, faithful, and better smelling than partners who induced low-orgasm rates, and also engaged in greater efforts to induce partner orgasm. Some assumptions and predictions of mate-choice hypotheses of female orgasm were supported, while other aspects of our findings provide reasons to remain sceptical.

  4. Behavioural changes, sharing behaviour and psychological responses after receiving direct-to-consumer genetic test results: a systematic review and meta-analysis.

    Science.gov (United States)

    Stewart, Kelly F J; Wesselius, Anke; Schreurs, Maartje A C; Schols, Annemie M W J; Zeegers, Maurice P

    2018-01-01

    It has been hypothesised that direct-to-consumer genetic tests (DTC-GTs) could stimulate health behaviour change. However, genetic testing may also lead to anxiety and distress or unnecessarily burden the health care system. The aim is to review and meta-analyse the effects of DTC-GT on (1) behaviour change, (2) psychological response and (3) medical consumption. A systematic literature search was performed in three databases, using "direct-to-consumer genetic testing" as a key search term. Random effects meta-analyses were performed when at least two comparable outcomes were available. After selection, 19 articles were included involving 11 unique studies. Seven studies involved actual consumers who paid the retail price, whereas four included participants who received free genetic testing as part of a research trial (non-actual consumers). In meta-analysis, 23% had a positive lifestyle change. More specifically, improved dietary and exercise practices were both reported by 12%, whereas 19% quit smoking. Seven percent of participants had subsequent preventive checks. Thirty-three percent shared their results with any health care professional and 50% with family and/or friends. Sub-analyses show that behaviour change was more prevalent among non-actual consumers, whereas sharing was more prevalent among actual consumers. Results on psychological responses showed that anxiety, distress and worry were low or absent and that the effect faded with time. DTC-GT has potential to be effective as a health intervention, but the right audience needs to be addressed with tailored follow-up. Research is needed to identify consumers who do and do not change behaviour or experience adverse psychological responses.

  5. Memory and other properties of multiple test procedures generated by entangled graphs.

    Science.gov (United States)

    Maurer, Willi; Bretz, Frank

    2013-05-10

    Methods for addressing multiplicity in clinical trials have attracted much attention during the past 20 years. They include the investigation of new classes of multiple test procedures, such as fixed sequence, fallback and gatekeeping procedures. More recently, sequentially rejective graphical test procedures have been introduced to construct and visualize complex multiple test strategies. These methods propagate the local significance level of a rejected null hypothesis to not-yet rejected hypotheses. In the graph defining the test procedure, hypotheses together with their local significance levels are represented by weighted vertices and the propagation rule by weighted directed edges. An algorithm provides the rules for updating the local significance levels and the transition weights after rejecting an individual hypothesis. These graphical procedures have no memory in the sense that the origin of the propagated significance level is ignored in subsequent iterations. However, in some clinical trial applications, memory is desirable to reflect the underlying dependence structure of the study objectives. In such cases, it would allow the further propagation of significance levels to be dependent on their origin and thus reflect the grouped parent-descendant structures of the hypotheses. We will give examples of such situations and show how to induce memory and other properties by convex combination of several individual graphs. The resulting entangled graphs provide an intuitive way to represent the underlying relative importance relationships between the hypotheses, are as easy to perform as the original individual graphs, remain sequentially rejective and control the familywise error rate in the strong sense. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Performance of four different rat strains in the autoshaping, two-object discrimination, and swim maze tests of learning and memory.

    Science.gov (United States)

    Andrews, J S; Jansen, J H; Linders, S; Princen, A; Broekkamp, C L

    1995-04-01

    The performance of four strains of rats commonly used in behavioural research was assessed in three different tests of learning and memory. The four strains included three outbred lines (Long-Evans, Sprague-Dawley, Wistar) and one inbred strain (S3). Learning and memory were tested using three different paradigms: autoshaping of a lever press, a two-object discrimination test, and performance in a two-island swim maze task. The pigmented strains showed better performance in the autoshaping procedure: the majority of the Long-Evans and the S3 rats acquired the response, and the majority of the Wistar and Sprague-Dawley failed to acquire the response in the set time. The albino strains were slightly better in the swim maze than the pigmented strains. There appeared to be a speed/accuracy trade-off in the strategy used to solve the task. This was also evident following treatment with the cholinergic-depleting agent hemicholinium-3. The performance of the Long-Evans rats was most affected by the treatment in terms of accuracy and the Wistar and Sprague-Dawleys in terms of speed. In the two-object discrimination test only the Long-Evans showed satisfactory performance and were able to discriminate a novel from a known object a short interval after initial exposure. These results show large task- and strain-dependent differences in performance in tests of learning and memory. Some of the performance variation may be due to emotional differences between the strains and may be alleviated by extra training. However, the response to pharmacological manipulation may require more careful evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Content addressable memories in scientific instruments

    International Nuclear Information System (INIS)

    Lotto, I. de; Golinelli, S.

    1975-01-01

    The content-addressable-memory feature of a new system designed in these laboratories for non-destructive testing of nuclear reactor pressure vessels based on acoustic emission analysis is presented. The content addressable memory is divided into two parts: the first selects the most frequent events among incoming ones (FES: Frequent Event Selection memory), the second stores the frequent events singled out (FEM: Frequent Event Memory). The statistical behaviour of FES is analyzed, and experimental results are compared with theoretical ones; the model presented proved to be a useful tool in dimensioning the instrument store capacity. (Auth.)

  8. Students Working Online for Group Projects: A Test of an Extended Theory of Planned Behaviour Model

    Science.gov (United States)

    Cheng, Eddie W. L.

    2017-01-01

    This study examined an extended theory of planned behaviour (TPB) model that specified factors affecting students' intentions to collaborate online for group work. Past behaviour, past experience and actual behavioural control were incorporated in the extended TPB model. The mediating roles of attitudes, subjective norms and perceived behavioural…

  9. Fission products and nuclear fuel behaviour under severe accident conditions part 1: Main lessons learnt from the first VERDON test

    Science.gov (United States)

    Pontillon, Y.; Geiger, E.; Le Gall, C.; Bernard, S.; Gallais-During, A.; Malgouyres, P. P.; Hanus, E.; Ducros, G.

    2017-11-01

    This paper describes the first VERDON test performed at the end of September 2011 with special emphasis on the behaviour of fission products (FP) and actinides during the accidental sequence itself. Two other papers discuss in detail the post-test examination results (SEM, EPMA and SIMS) of the VERDON-1 sample. The first VERDON test was devoted to studying UO2 fuel behaviour and fission product releases under reducing conditions at very high temperature (∼2883 K), which was able to confirm the very good performance of the VERDON loop. The fuel sample did not lose its integrity during this test. According to the FP behaviour measured by the online gamma station (fuel sight), the general classification of the FP in relation to their released fraction is very accurate, and the burn-up effect on the release rate is clearly highlighted.

  10. Maternal depression and co-occurring antisocial behaviour: testing maternal hostility and warmth as mediators of risk for offspring psychopathology.

    Science.gov (United States)

    Sellers, Ruth; Harold, Gordon T; Elam, Kit; Rhoades, Kimberly A; Potter, Robert; Mars, Becky; Craddock, Nick; Thapar, Anita; Collishaw, Stephan

    2014-01-01

    Disruption in the parent-child relationship is a commonly hypothesized risk factor through which maternal depression may increase risk for offspring psychopathology. However, maternal depression is commonly accompanied by other psychopathology, including antisocial behaviour. Few studies have examined the role of co-occurring psychopathology in depressed mothers. Using a longitudinal study of offspring of mothers with recurrent depression, we aimed to test whether maternal warmth/hostility mediated links between maternal depression severity and child outcomes, and how far direct and indirect pathways were robust to controls for co-occurring maternal antisocial behaviour. Mothers with a history of recurrent major depressive disorder and their adolescent offspring (9-17 years at baseline) were assessed three times between 2007 and 2010. Mothers completed questionnaires assessing their own depression severity and antisocial behaviour at Time 1 (T1). The parent-child relationship was assessed using parent-rated questionnaire and interviewer-rated 5-min speech sample at Time 2 (T2). Offspring symptoms of depression and disruptive behaviours were assessed using the Child and Adolescent Psychiatric Assessment at Time 3 (T3). Maternal hostility and warmth, respectively, mediated the association between maternal depression severity and risk for offspring psychopathology. However, the effects were attenuated when maternal antisocial behaviour was included in the analysis. In tests of the full theoretical model, maternal antisocial behaviour predicted both maternal hostility and low warmth, maternal hostility predicted offspring disruptive behaviour disorder symptoms, but not depression, and maternal warmth was not associated with either child outcome. Parenting interventions aimed at reducing hostility may be beneficial for preventing or reducing adolescent disruptive behaviours in offspring of depressed mothers, especially when depressed mothers report co

  11. An automatic sodium-loop for testing the lon-term behaviour of sintered bodies flowed through by gas

    International Nuclear Information System (INIS)

    Barkleit, G.; George, G.; Haase, I.; Kiessling, W.

    1980-08-01

    An automatic sodium loop NAKOS for testing the long-term behaviour of porous stainless steel bodies which are flowed through by gas is described. The loop using a special safety protection system is capable of working without control up to 1000 h. During a 500 h-experiment the safety system and the gas permeability measuring method for testing the porous bodies were tested. Both first results of the behaviour of sintered bodies in liquid sodium of high purity and temperatures of about 850 K and some details of the production of these bodies are given. (author)

  12. A test of the functional avoidance hypothesis in the development of overgeneral autobiographical memory.

    Science.gov (United States)

    Hallford, D J; Austin, D W; Raes, F; Takano, K

    2018-04-18

    Overgeneral memory (OGM) refers to the failure to recall memories of specific personally experienced events, which occurs in various psychiatric disorders. One pathway through which OGM is theorized to develop is the avoidance of thinking of negative experiences, whereby cumulative avoidance may maladaptively generalize to autobiographical memory (AM) more broadly. We tested this, predicting that negative experiences would interact with avoidance to predict AM specificity. In Study 1 (N = 281), negative life events (over six months) and daily hassles (over one month) were not related to AM specificity, nor was avoidance, and no interaction was found. In Study 2 (N = 318), we revised our measurements and used an increased timeframe of 12 months for both negative life events and daily hassles. The results showed no interaction effect for negative life events, but they did show an interaction for daily hassles, whereby increased hassles and higher avoidance of thinking about them were associated with reduced AM specificity, independent of general cognitive avoidance and depressive symptoms. No evidence was found that cognitive avoidance or AM specificity moderated the effect of negative experiences on depressive symptoms. Our findings suggest that life events over 6-12 months are not associated with AM specificity, but chronic daily hassles over 12 months predict reduced AM specificity when individuals avoid thinking about them. The findings provide evidence for the functional-avoidance hypothesis of OGM development and future directions for longitudinal studies.

  13. The touchscreen operant platform for testing working memory and pattern separation in rats and mice.

    Science.gov (United States)

    Oomen, Charlotte A; Hvoslef-Eide, Martha; Heath, Christopher J; Mar, Adam C; Horner, Alexa E; Bussey, Timothy J; Saksida, Lisa M

    2013-10-01

    The automated touchscreen operant chamber for rats and mice allows for the assessment of multiple cognitive domains within the same testing environment. This protocol presents the location discrimination (LD) task and the trial-unique delayed nonmatching-to-location (TUNL) task, which both assess memory for location. During these tasks, animals are trained to a predefined criterion during ∼20-40 daily sessions. In LD sessions, touching the same location on the screen is rewarded on consecutive trials, followed by a reversal of location-reward contingencies. TUNL, a working memory task, requires animals to 'nonmatch' to a sample location after a delay. In both the LD and TUNL tasks, spatial similarity can be varied, allowing assessment of pattern separation ability, a function that is thought to be performed by the dentate gyrus (DG). These tasks are therefore particularly useful in animal models of hippocampal, and specifically DG, function, but they additionally permit discernment of changes in pattern separation from those in working memory.

  14. Results from the First Two Flights of the Static Computer Memory Integrity Testing Experiment

    Science.gov (United States)

    Hancock, Thomas M., III

    1999-01-01

    This paper details the scientific objectives, experiment design, data collection method, and post flight analysis following the first two flights of the Static Computer Memory Integrity Testing (SCMIT) experiment. SCMIT is designed to detect soft-event upsets in passive magnetic memory. A soft-event upset is a change in the logic state of active or passive forms of magnetic memory, commonly referred to as a "Bitflip". In its mildest form a soft-event upset can cause software exceptions, unexpected events, start spacecraft safeing (ending data collection) or corrupted fault protection and error recovery capabilities. In it's most severe form loss of mission or spacecraft can occur. Analysis after the first flight (in 1991 during STS-40) identified possible soft-event upsets to 25% of the experiment detectors. Post flight analysis after the second flight (in 1997 on STS-87) failed to find any evidence of soft-event upsets. The SCMIT experiment is currently scheduled for a third flight in December 1999 on STS-101.

  15. Activity of human hippocampal formation and amygdala neurons during memory testing.

    Science.gov (United States)

    Halgren, E; Babb, T L; Crandall, P H

    1978-11-01

    Single and multiple unit recordings were made from fine wires stereotaxically implanted in the hippocampus (HC), hippocampal gyrus (HCG), and amygdala (Am) of psychomotor epileptics. During a series of memory and control tests presented on slides, 21 of 155 HCG units, 15 of 59 HC units, and 2 of 54 Am units showed what appeared to be simple phasic or tonic visual responses. Twenty-seven other units, found only in the HCG, changed firing only during slides requiring a choice ('choice units'). A given choice unit responded during choices indicated verbally or manually, and during tasks requiring recall of Recent Memory, various visual discriminations, and expressions of preference. Choice units were not affected by sensory stimulation or motor activity in contexts not requiring choice. Phasically inhibited choice units had higher firing rates and lower signal-to-noise ratios than tonically excited units. Whether an electrode recorded a choice unit was unrelated to if it recorded a response to hyperventilation, or was in an area of epileptic pathology. Recordings were also made during an interview lasting several hours and eliciting a wide range of behaviors. Five of the 131 HCG units fired in repeated extended bursts, at least 50 times background during recall of word pairs or of the patient's hospital room. The unit response did not occur during numerous control tasks possessing similar overt sensory, motor, and social concomitants, but not requiring Recent Memory.

  16. The Memory Failures of Everyday (MFE) test: normative data in adults.

    Science.gov (United States)

    Montejo Carrasco, Pedro; Montenegro Peña, Mercedes; Sueiro, Manuel J

    2012-11-01

    One approach to the study of everyday memory failures is to use multiple-item questionnaires. The Memory Failures of Everyday (MFE) test is one of the most frequently used in Spain. Our objective is to provide normative data from the MFE in a sample of healthy, Spanish, adult participants for use in clinical practice. The sample consists of 647 employees at a large company ranging in age from 19-64 years-old. Everyday memory failures were evaluated by means of the MFE with the following response format: 0-2 (0 = never or rarely; 1 = occasionally, sometimes; 2 = frequently, often). Mean MFE = 15.25 (SD = 7.50), range 0-40. Correlation with age: .133 (p = .001); and with years of education: - .059 (n.s.). A constant increase in MFE was not observed across age groups (F = 4, 59; p = .003, eta2 = .02), but differences were revealed between the 19-29 and 40-49 age groups; no differences were observed between the remaining age groups. Only slight differences between men and women occurred, the women's mean being slightly higher than the men's, but the confidence intervals overlapped (F = 5, 71; p = .017, eta2 = .01). These results indicate that age, years of education, and sex had no significant effects. In light of the above, the sample was viewed as a whole when computing the percentiles reported here.

  17. Electrochemical behaviour of aluminum alloy containing various stanum concentration tested in tropical seawater

    International Nuclear Information System (INIS)

    Siti Radiah Mohd Kamarudin; Muhamad Daud; Mohd Shariff Satar

    2004-01-01

    A study has been carried out to investigate the electrochemical behaviour of sacrificial anodes with different Sh concentration in tropical seawater environment. In this work, samples of Aluminum alloy with the addition of Sn in a range of 1. 0% - 1. 7% were tested in tropical seawater at room temperature. Tafel technique was used to produce a graph of the measured current versus potential for each different Sh concentration of aluminum alloy. The results show that the variation in alloy compositions affected the values of corrosion rate, corrosion current density and potential compared to alloy without Sn content. Furthermore, it was found that small addition of Sn successfully increased aluminum ion dissolution into seawater by producing a higher value of corrosion current density and corrosion rate. (Author)

  18. Constant strain rate test and SCC-behaviour of stainless steels

    International Nuclear Information System (INIS)

    Krauss, H.; Speckhardt, H.

    1979-01-01

    In the present work, the stress corrosion cracking behaviour in boiling aqueous 35% magnesium chloride solution under conditions of no external current was investigated as a function of the defined extension rates for the two austenitic steels X 2 CrNi 189 and X 2 CrNiSi 1815, as well as for both ferritic austenitic steels X 6 CrNiMoCu 217 and X 2 CrNiMoN 225. The endurance time found until cracking, the maximum tensile stress, the sample stretching up to cracking and the relative rupture energy were determined for the evaluation, as well as metallographic investigations to describe the crack picture, test surface appearance and attack picture carried out. (orig.) 891 RW/orig. 892 BRE [de

  19. The effectiveness of test-enhanced learning depends on trait test anxiety and working-memory capacity.

    Science.gov (United States)

    Tse, Chi-Shing; Pu, Xiaoping

    2012-09-01

    Despite being viewed as a better way to enhance learning than repeated study, it has not been clear whether repeated testing is equally effective for students with a wide range of cognitive abilities. The current study examined whether test-enhanced learning would be equally beneficial to participants with varied working-memory capacity (WMC) and trait test anxiety (TA). Chinese-English bilingual undergraduates in Hong Kong were recruited as participants. They acquired Swahili-English word pairs (half via repeated study and half via repeated testing) and performed a delayed cued-recall test for all pairs about one week after the acquisition phase. Their WMC and TA were estimated by Unsworth, Heitz, Schrock, and Engle's (2005) operation-span task and the Chinese version of Spielberger's (1980) Test Anxiety Inventory, respectively. We replicated the typical testing effect: Participants performed better for pairs in the repeated-testing condition than those in the repeated-study condition. Regression analyses showed that, (a) relative to other participants, those with lower WMC and higher TA made more intralist intrusion errors (i.e., recalling a wrong English translation to a Swahili word cue) during the acquisition phase, and (b) the testing effect was negatively correlated with TA for participants with lower WMC, but was not correlated with TA for participants with higher WMC. This demonstrates a boundary condition for the use of test-enhanced learning. Implications of these findings for theories of the testing effect (e.g., Pyc & Rawson's, 2010, mediator-effectiveness hypothesis) and their application in classroom settings are discussed.

  20. Analysis of memory deficits following chemotherapy in breast cancer survivors: evidence from the doors and people test.

    Science.gov (United States)

    Prokasheva, Svetlana; Faran, Yifat; Cwikel, Julie; Geffen, David B

    2011-01-01

    Studies of cognitive effects of chemotherapy among breast cancer patients show that not all women who are exposed to chemotherapy develop cognitive dysfunction and that the observed declines in cognitive functioning may be quite subtle. The use of measures that are sensitive to subtle cognitive decline are recommended yet rarely used among clinical populations. The purpose of this study is to specify the types of memory changes observed among breast cancer survivors treated with chemotherapy and tamoxifen, by using an analytic test of memory, the Doors and People test, which uses age-adjusted norms. The participants were 40 women who were survivors of breast cancer, 20 of whom had completed chemotherapy treatment and 20 women who were treated only with tamoxifen. There were no significant differences between the two groups in overall scores and in all four subtests: visual memory, verbal memory, recall, and recognition measured by age-adjusted scores. Forty percent of patients in both of the groups were classified as having mild impairment in episodic memory. No between-group differences were found in the frequency of subjective, cognitive complaints. Subjective complaints were reported by 69% of patients but were unrelated to objective performance. Memory deficits were observed in breast cancer patients who receive either chemotherapy or tamoxifen alone compared to age-adjusted norms. The Doors and People Test is a sensitive measure of memory deficits that is feasible for use with clinical populations of breast cancer patients in order to monitor changes in cognitive function.

  1. Test your memory-Turkish version (TYM-TR): reliability and validity study of a cognitive screening test.

    Science.gov (United States)

    Maviş, Ilknur; Özbabalik Adapinar, Belgin Demet; Yenilmez, Çinar; Aydin, Ayşe; Olgun, Engin; Bal, Cengiz

    2015-01-01

    The test your memory (TYM) is reported to be a sensitive cognitive function assessment scale for people with dementia. The aim of the present study was to investigate the reliability and validity of an adapted Turkish version of the TYM (TYM-TR) among Turkish dementia patients. The TYM-TR was given to 59 patients with dementia aged 60+ and 336 normal controls aged 23-75+. The diagnostic utility of the TYM-TR was compared with that of the mini-mental state examination (MMSE) to validate it. The internal consistency of the TYM-TR was a = 0.85. The test-retest reliability was 0.97 (P reliability and validity to distinguish dementia in the Turkish population.

  2. A novel approach to detect test-seeking behaviour in the blood donor population : making the invisible visible

    NARCIS (Netherlands)

    de Vos, A. S.; Lieshout-Krikke, R. W.; Slot, E.; Cator, E. A.; Janssen, M. P.

    2016-01-01

    Background and Objectives: Individuals may donate blood in order to determine their infection status after exposure to an increased infection risk. Such test-seeking behaviour decreases transfusion safety. Instances of test seeking are difficult to substantiate as donors are unlikely to admit to

  3. Environmental Knowledge and Behavioural Outcomes of Tourism Students in Australia: Towards Testing a Range of Mediation and Moderated Mediation Effects

    Science.gov (United States)

    Fatima, Johra Kayeser; Khan, Habib Zaman; Goh, Edmund

    2016-01-01

    Our study examines the environmental knowledge (EK) and behavioural outcomes of students studying ecotourism in Sydney, Australia. Three competing models were tested to examine the relationships between EK, participation intention (PI) in ecotourism programs, landscape likeability (LL) and social interactions (SI); and the study also tested the…

  4. A score based on screening tests to differentiate mild cognitive impairment from subjective memory complaints

    Directory of Open Access Journals (Sweden)

    Fábio Henrique de Gobbi Porto

    2013-09-01

    Full Text Available It is not easy to differentiate patients with mild cognitive impairment (MCI from subjective memory complainers (SMC. Assessments with screening cognitive tools are essential, particularly in primary care where most patients are seen. The objective of this study was to evaluate the diagnostic accuracy of screening cognitive tests and to propose a score derived from screening tests. Elderly subjects with memory complaints were evaluated using the Mini Mental State Examination (MMSE and the Brief Cognitive Battery (BCB. We added two delayed recalls in the MMSE (a delayed recall and a late-delayed recall, LDR, and also a phonemic fluency test of letter P fluency (LPF. A score was created based on these tests. The diagnoses were made on the basis of clinical consensus and neuropsychological testing. Receiver operating characteristic curve analyses were used to determine area under the curve (AUC, the sensitivity and specificity for each test separately and for the final proposed score. MMSE, LDR, LPF and delayed recall of BCB scores reach statistically significant differences between groups (P=0.000, 0.03, 0.001 and 0.01, respectively. Sensitivity, specificity and AUC were MMSE: 64%, 79% and 0.75 (cut off <29; LDR: 56%, 62% and 0.62 (cut off <3; LPF: 71%, 71% and 0.71 (cut off <14; delayed recall of BCB: 56%, 82% and 0.68 (cut off <9. The proposed score reached a sensitivity of 88% and 76% and specificity of 62% and 75% for cut off over 1 and over 2, respectively. AUC were 0.81. In conclusion, a score created from screening tests is capable of discriminating MCI from SMC with moderate to good accurancy.

  5. A computer vision-based automated Figure-8 maze for working memory test in rodents.

    Science.gov (United States)

    Pedigo, Samuel F; Song, Eun Young; Jung, Min Whan; Kim, Jeansok J

    2006-09-30

    The benchmark test for prefrontal cortex (PFC)-mediated working memory in rodents is a delayed alternation task utilizing variations of T-maze or Figure-8 maze, which requires the animals to make specific arm entry responses for reward. In this task, however, manual procedures involved in shaping target behavior, imposing delays between trials and delivering rewards can potentially influence the animal's performance on the maze. Here, we report an automated Figure-8 maze which does not necessitate experimenter-subject interaction during shaping, training or testing. This system incorporates a computer vision system for tracking, motorized gates to impose delays, and automated reward delivery. The maze is controlled by custom software that records the animal's location and activates the gates according to the animal's behavior and a control algorithm. The program performs calculations of task accuracy, tracks movement sequence through the maze, and provides other dependent variables (such as running speed, time spent in different maze locations, activity level during delay). Testing in rats indicates that the performance accuracy is inversely proportional to the delay interval, decreases with PFC lesions, and that animals anticipate timing during long delays. Thus, our automated Figure-8 maze is effective at assessing working memory and provides novel behavioral measures in rodents.

  6. Smell test predicts performance on delayed recall memory test in elderly with depression.

    Science.gov (United States)

    Scalco, Monica Z; Streiner, David L; Rewilak, Dmytro; Castel, Saulo; Van Reekum, Robert

    2009-04-01

    Elderly with depression are at increased risk for cognitive dysfunction and dementia. Smell tests are correlated with performance on cognitive tests in the elderly and therefore might serve as a screening test for cognitive impairment in depressed elderly. To assess the validity of the CC-SIT (Cross-Cultural Smell Identification Test) as a screening test for cognitive impairment in elderly with depression. Forty-one patients, aged 60 and over, were assessed with the CC-SIT and CVLT (California Verbal Learning Test) after 3 months treatment of a Major Depressive Episode (DSM-IV) at the Day Hospital for Depression, Baycrest. Patients already diagnosed with dementia, or other psychiatric and neurological disorders, were excluded. Receiver Operating Characteristics (ROC) analysis was applied to assess the CC-SIT's accuracy in identifying individuals with impairment (2 SD below the mean for age and education or less) on CVLT delayed recall trials. Forty-one patients (33 women and eight men) were assessed. Mean age was 76.8 (SD: 6.5), mean HRSD scores before treatment was 22.0 (SD: 5.1). Nine patients had impairment on CVLT delayed recall measures. The area under the ROC curve was 0.776 (95% CI = 0.617-0.936). Our results support the use of the CC-SIT as a screening tool for cognitive impairment among elderly with depression as an indicator for the need of a comprehensive neuropsychological evaluation. Replication with larger samples is necessary. (c) 2008 John Wiley & Sons, Ltd.

  7. Testing five social-cognitive models to explain predictors of personal oral health behaviours and intention to improve them.

    Science.gov (United States)

    Dumitrescu, Alexandrina L; Dogaru, Beatrice C; Duta, Carmen; Manolescu, Bogdan N

    2014-01-01

    To test the ability of several social-cognitive models to explain current behaviour and to predict intentions to engage in three different health behaviours (toothbrushing, flossing and mouthrinsing). Constructs from the health belief model (HBM), theory of reasoned action (TRA), theory of planned behaviour (TPB) and the motivational process of the health action process approach (HAPA) were measured simultaneously in an undergraduate student sample of 172 first-year medical students. Regarding toothbrushing, the TRA, TPB, HBM (without the inclusion of self-efficacy SE), HBM+SE and HAPA predictor models explained 7.4%, 22.7%, 10%, 10.2% and 10.1%, respectively, of the variance in behaviour and 7.5%, 25.6%, 12.1%, 17.5% and 17.2%, respectively, in intention. Regarding dental flossing, the TRA, TPB, HBM, HBM+SE and HAPA predictor models explained 39%, 50.6, 24.1%, 25.4% and 27.7%, respectively, of the variance in behaviour and 39.4%, 52.7%, 33.7%, 35.9% and 43.2%, respectively, in intention. Regarding mouthrinsing, the TRA, TPB, HBM, HBM+SE and HAPA predictor models explained 43.9%, 45.1%, 20%, 29% and 36%, respectively, of the variance in behaviour and 58%, 59.3%, 49.2%, 59.8% and 66.2%, respectively, in intention. The individual significant predictors for current behaviour were attitudes, barriers and outcome expectancy. Our findings revealed that the theory of planned behaviours and the health action process approach were the best predictor of intentions to engage in both behaviours.

  8. Dynamic behaviour of raft and pile foundations tests and computational models. Pt. 1

    International Nuclear Information System (INIS)

    Betbeder, J.; Garnier, J.C.; Gauvain, J.; Jeandidier, C.

    1981-01-01

    Pile foundations are commonly used for many types of buildings where the bearing capacity of soil is poor. For nuclear power plants buildings, however, there seems to be a fairly general reluctancy to accept design on piles, as it is considered difficult to demonstrate the safety of these foundations with respect to earthquakes, due to the relative lack of validation of the currently available aseismic design methods. Being conscious that pile foundations might be worth considering for future nuclear sites in France and that the reliability of design methods should be backed by experimental data, ELECTRICITE DE FRANCE decided in 1978 to undertake a series of tests, aimed at assessing the validity of computational models for seismic behaviour of pile foundations and trying to define better models if necessary. These tests on reduced scale structure, including various types of raft and pile foundations and different kinds of dynamic excitation (harmonic, earthquake simulation, impulsive release of a static force) have been made at the NICE airport site. The present paper deals with the general description of the tests and the first part of interpretation work, limited to in-structure harmonic excitation and earthquake simulation tests analyzed by simple spring -dashpot analytical models. The two following papers (K5-6 and K5-7) are devoted to specialized topics in relation with the interpretation of tests, i-e ground motions analysis for earthquake simulation and research work on a new computational model. Although preliminary conclusions can be drawn from the results obtained so far, further work will be necessary to reach a conclusive assessment on this difficult subject. (orig.)

  9. Phase characterisation and mechanical behaviour of Fe–B modified Cu–Zn–Al shape memory alloys

    Directory of Open Access Journals (Sweden)

    Kenneth Kanayo Alaneme

    2017-04-01

    Full Text Available The microstructures, phase characteristics and mechanical behaviour of Cu–Zn–Al alloys modified with Fe, B, and Fe–B mixed micro-alloying additions has been investigated. Cu–Zn–Al alloys were produced by casting with and without the addition of the microelements (Fe, B and Fe–B. The alloys were subjected to a homogenisation – cold rolling – annealing treatment schedule, before the alloys were machined to specifications for tensile test, fracture toughness, and hardness measurement. Optical, scanning electron microscopy and X-ray diffraction analysis were utilised for microstructural and phase characterisation of the alloys. A distinct difference in grain morphology was observed in the alloys produced – the unmodified alloy had predominantly needle-like lath martensite structure with sharp grain edges while significantly larger transverse grain size and curve edged/near elliptical grain shape was observed for the modified Cu–Zn–Al alloys. Cu–Zn with fcc structure was the predominant phase identified in the alloys while Cu–Al with bcc structure was the secondary phase observed. The hardness of the unmodified Cu–Zn–Al alloy was higher than that of the modified alloys with reductions in hardness ranging between 32.4 and 51.5%. However, the tensile strength was significantly lower than that of the modified alloy grades (28.37–52.74% increase in tensile strength was achieved with the addition of micro-alloying elements. Similarly, the percent elongation and fracture toughness (10–23% increase of the modified alloy was higher than that of the unmodified alloy grade. The modified alloy compositions mostly exhibited fracture features indicative of a fibrous micro-mechanism to crack initiation and propagation, characterised by the prevalence of dimpled rupture.

  10. Neural correlates of retrieval-based memory enhancement: an fMRI study of the testing effect.

    Science.gov (United States)

    Wing, Erik A; Marsh, Elizabeth J; Cabeza, Roberto

    2013-10-01

    Restudying material is a common method for learning new information, but not necessarily an effective one. Research on the testing effect shows that practice involving retrieval from memory can facilitate later memory in contrast to passive restudy. Despite extensive behavioral work, the brain processes that make retrieval an effective learning strategy remain unclear. In the present experiment, we explored how initially retrieving items affected memory a day later as compared to a condition involving traditional restudy. In contrast to restudy, initial testing that contributed to future memory success was associated with engagement of several regions including the anterior hippocampus, lateral temporal cortices, and medial prefrontal cortex (PFC). Additionally, testing enhanced hippocampal connectivity with ventrolateral PFC and midline regions. These findings indicate that the testing effect may be contingent on processes that are typically thought to support memory success at encoding (e.g. relational binding, selection and elaboration of semantically-related information) in addition to those more often associated with retrieval (e.g. memory search). © 2013 Elsevier Ltd. All rights reserved.

  11. Memory for objects and startle responsivity in the immediate aftermath of exposure to the Trier Social Stress Test.

    Science.gov (United States)

    Herten, Nadja; Pomrehn, Dennis; Wolf, Oliver T

    2017-05-30

    Previously, we observed enhanced long-term memory for objects used (central objects) by committee members in the Trier Social Stress Test (TSST) on the next day. In addition, startle responsivity was increased. However, response specificity to an odour involved in the stressful episode was lacking and recognition memory for the odour was poor. In the current experiments, immediate effects of the stressor on memory and startle responsivity were investigated. We hypothesised memory for central objects of the stressful episode and startle response specificity to an odour ambient during the TSST to be enhanced shortly after it, in contrast to the control condition (friendly TSST). Further, memory for this odour was also assumed to be increased in the stress group. We tested 70 male (35) and female participants using the TSST involving objects and an ambient odour. After stress induction, a startle paradigm including olfactory and visual stimuli was conducted. Indeed, memory for central objects was significantly enhanced in immediate aftermath of the stressor. Startle responsivity increased at a trend level, particularly with regard to the odour involved in the stressful episode. Moreover, the stress group descriptively tended towards a better recognition of the odour involved. The study shows that stress enhances memory for central aspects of a stressful situation before consolidation processes come into play. In addition, results preliminarily suggest that the impact of stress on startle responsivity increases in strength but decreases in specificity during the first 24h after stress exposure. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Habitat stability, predation risk and ‘memory syndromes’

    Science.gov (United States)

    Dalesman, S.; Rendle, A.; Dall, S.R.X.

    2015-01-01

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonstrates consistency among memory traits (‘memory syndrome’) related to threat avoidance and foraging. We used eight populations originating from three different habitat types: i) laboratory populations (stable habitat, predator-free); ii) river populations (fairly stable habitat, fish predation); and iii) ditch populations (unstable habitat, invertebrate predation). At a population level, there was a negative relationship between memories related to threat avoidance and food selectivity, but no consistency within habitat type. At an individual level, covariance between memory traits was dependent on habitat. Laboratory populations showed no covariance among memory traits, whereas river populations showed a positive correlation between food memories, and ditch populations demonstrated a negative relationship between threat memory and food memories. Therefore, selection pressures among habitats appear to act independently on memory trait covariation at an individual level and the average response within a population. PMID:26013966

  13. Testing the mate-choice hypothesis of the female orgasm: disentangling traits and behaviours

    Directory of Open Access Journals (Sweden)

    James M. Sherlock

    2016-10-01

    Full Text Available Background: The evolution of the female orgasm in humans and its role in romantic relationships is poorly understood. Whereas the male orgasm is inherently linked to reproduction, the female orgasm is not linked to obvious reproductive or survival benefits. It also occurs less consistently during penetrative sex than does the male orgasm. Mate-choice hypotheses posit that the wide variation in female orgasm frequency reflects a discriminatory mechanism designed to select high-quality mates. Objective: We aimed to determine (1 whether women report that their orgasm frequency varies between partners, (2 whether this variation reflects mates' personal characteristics, and (3 whether this variation reflects own and partner sexual behaviour during intercourse. Design: We collected survey data from 103 women who rated (1 the extent to which their orgasm frequency varied between partners, (2 the characteristics of previous sexual partners who induced high-orgasm frequency and those who induced low-orgasm frequency, and (3 the specific behaviours during sex with those partners. This is the first study to test within-woman variation in orgasm and partner traits. Results: Overall, women reported variation in their orgasm rates with different partners. Partners who induced high-orgasm rates were rated as more humorous, creative, warm, faithful, and better smelling than partners who induced low-orgasm rates, and also engaged in greater efforts to induce partner orgasm. Conclusions: Some assumptions and predictions of mate-choice hypotheses of female orgasm were supported, while other aspects of our findings provide reasons to remain sceptical.

  14. Heat Transfer Behaviour and Thermohydraulics Code Testing for Supercritical Water Cooled Reactors (SCWRs)

    International Nuclear Information System (INIS)

    2014-08-01

    The supercritical water cooled reactor (SCWR) is an innovative water cooled reactor concept which uses water pressurized above its thermodynamic critical pressure as the reactor coolant. This concept offers high thermal efficiencies and a simplified reactor system, and is hence expected to help to improve economic competitiveness. Various kinds of SCWR concepts have been developed, with varying combinations of reactor type (pressure vessel or pressure tube) and core spectrum (thermal, fast or mixed). There is great interest in both developing and developed countries in the research and development (R&D) and conceptual design of SCWRs. Considering the high interest shown in a number of Member States, the IAEA established in 2008 the Coordinated Research Project (CRP) on Heat Transfer Behaviour and Thermo-hydraulics Code Testing for SCWRs. The aim was to foster international collaboration in the R&D of SCWRs in support of Member States’ efforts and under the auspices of the IAEA Nuclear Energy Department’s Technical Working Groups on Advanced Technologies for Light Water Reactors (TWG-LWR) and Heavy Water Reactors (TWG-HWR). The two key objectives of the CRP were to establish accurate databases on the thermohydraulics of supercritical pressure fluids and to test analysis methods for SCWR thermohydraulic behaviour to identify code development needs. In total, 16 institutes from nine Member States and two international organizations were involved in the CRP. The thermohydraulics phenomena investigated in the CRP included heat transfer and pressure loss characteristics of supercritical pressure fluids, development of new heat transfer prediction methods, critical flow during depressurization from supercritical conditions, flow stability and natural circulation in supercritical pressure systems. Two code testing benchmark exercises were performed for steady state heat transfer and flow stability in a heated channel. The CRP was completed with the planned outputs in

  15. Heat Transfer Behaviour and Thermohydraulics Code Testing for Supercritical Water Cooled Reactors (SCWRs)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-08-15

    The supercritical water cooled reactor (SCWR) is an innovative water cooled reactor concept which uses water pressurized above its thermodynamic critical pressure as the reactor coolant. This concept offers high thermal efficiencies and a simplified reactor system, and is hence expected to help to improve economic competitiveness. Various kinds of SCWR concepts have been developed, with varying combinations of reactor type (pressure vessel or pressure tube) and core spectrum (thermal, fast or mixed). There is great interest in both developing and developed countries in the research and development (R&D) and conceptual design of SCWRs. Considering the high interest shown in a number of Member States, the IAEA established in 2008 the Coordinated Research Project (CRP) on Heat Transfer Behaviour and Thermo-hydraulics Code Testing for SCWRs. The aim was to foster international collaboration in the R&D of SCWRs in support of Member States’ efforts and under the auspices of the IAEA Nuclear Energy Department’s Technical Working Groups on Advanced Technologies for Light Water Reactors (TWG-LWR) and Heavy Water Reactors (TWG-HWR). The two key objectives of the CRP were to establish accurate databases on the thermohydraulics of supercritical pressure fluids and to test analysis methods for SCWR thermohydraulic behaviour to identify code development needs. In total, 16 institutes from nine Member States and two international organizations were involved in the CRP. The thermohydraulics phenomena investigated in the CRP included heat transfer and pressure loss characteristics of supercritical pressure fluids, development of new heat transfer prediction methods, critical flow during depressurization from supercritical conditions, flow stability and natural circulation in supercritical pressure systems. Two code testing benchmark exercises were performed for steady state heat transfer and flow stability in a heated channel. The CRP was completed with the planned outputs in

  16. Knowledge, attitudes and intended behaviours towards HIV testing and self-protection: a survey of Omani pregnant women.

    Science.gov (United States)

    Al-Jabri, A A; Youssef, R M; Hasson, S S; Balkhair, A A; Al-Belushi, M; Al-Saadoon, M; Mathew, M; Al-Mahroqi, S; Said, E; Koh, C Y; Idris, M A

    2014-10-20

    Routine HIV testing of all pregnant women in Oman has been introduced without prior knowledge of women's attitudes towards testing or their behaviour in the event of a positive test. This study recruited 1000 Omani pregnant women from antenatal clinics to explore their knowledge of HIV/AIDS, attitudes towards HIV testing and intended behaviours in the event of a positive test. Mother-to-child transmission was recognized by 86.6% of the women but only 21.0% knew that it was preventable and a few acknowledged the important role of antiviral drugs. Half of the women (51.9%) reported having been tested for HIV and 75.8% agreed about routine HIV testing for all pregnant women. A higher level of knowledge was significantly associated with a favourable intended behaviour related to voluntary testing, disclosure and seeking professional assistance in the event of a positive HIV test. The results are discussed in relation to opt-in and opt-out approaches to voluntary testing during pregnancy.

  17. A Comparison of Laboratory and Clinical Working Memory Tests and Their Prediction of Fluid Intelligence

    Science.gov (United States)

    Shelton, Jill T.; Elliott, Emily M.; Hill, B. D.; Calamia, Matthew R.; Gouvier, Wm. Drew

    2010-01-01

    The working memory (WM) construct is conceptualized similarly across domains of psychology, yet the methods used to measure WM function vary widely. The present study examined the relationship between WM measures used in the laboratory and those used in applied settings. A large sample of undergraduates completed three laboratory-based WM measures (operation span, listening span, and n-back), as well as the WM subtests from the Wechsler Adult Intelligence Scale-III and the Wechsler Memory Scale-III. Performance on all of the WM subtests of the clinical batteries shared positive correlations with the lab measures; however, the Arithmetic and Spatial Span subtests shared lower correlations than the other WM tests. Factor analyses revealed that a factor comprising scores from the three lab WM measures and the clinical subtest, Letter-Number Sequencing (LNS), provided the best measurement of WM. Additionally, a latent variable approach was taken using fluid intelligence as a criterion construct to further discriminate between the WM tests. The results revealed that the lab measures, along with the LNS task, were the best predictors of fluid abilities. PMID:20161647

  18. Comparison of Test Your Memory and Montreal Cognitive Assessment Measures in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Emily J. Henderson

    2016-01-01

    Full Text Available Background. MoCA is widely used in Parkinson’s disease (PD to assess cognition. The Test Your Memory (TYM test is a cognitive screening tool that is self-administered. Objectives. We sought to determine (a the optimal value of TYM to discriminate between PD patients with and without cognitive deficits on MoCA testing, (b equivalent MoCA and TYM scores, and (c interrater reliability in TYM testing. Methods. We assessed the discriminant ability of TYM and the equivalence between TYM and MoCA scores and measured the interrater reliability between three raters. Results. Of the 135 subjects that completed both tests, 55% had cognitive impairment according to MoCA. A MoCA score of 25 was equivalent to a TYM score of 43-44. The area under the receiver operator characteristic (ROC curve for TYM to differentiate between PD-normal and PD-cognitive impairment was 0.82 (95% CI 0.75 to 0.89. The optimal cutoff to distinguish PD-cognitive impairment from PD-normal was ≤45 (sensitivity 90.5%, specificity 59% thereby correctly classifying 76.3% of patients with PD-cognitive impairment. Interrater agreement was high (0.97 and TYM was completed in under 7 minutes (interquartile range 5.33 to 8.52 minutes. Conclusions. The TYM test is a useful and less resource intensive screening test for cognitive deficits in PD.

  19. The case for testing memory with both stories and word lists prior to dbs surgery for Parkinson's Disease.

    Science.gov (United States)

    Zahodne, Laura B; Bowers, Dawn; Price, Catherine C; Bauer, Russell M; Nisenzon, Anne; Foote, Kelly D; Okun, Michael S

    2011-04-01

    Patients seeking deep brain stimulation (DBS) surgery for Parkinson's disease (PD) typically undergo neuropsychological assessment to determine candidacy for surgery, with poor memory performance interpreted as a contraindication. Patients with PD may exhibit worse memory for word lists than for stories due to the lack of inherent organization in a list of unrelated words. Unfortunately, word list and story tasks are typically developed from different normative datasets, and the existence of a memory performance discrepancy in PD has been challenged. We compared recall of stories and word lists in 35 non-demented PD candidates for DBS. We administered commonly used neuropsychological measures of word list and story memory (Hopkins Verbal Learning Test, Logical Memory), along with a second word list task that was co-normed with the story task. Age-corrected scores were higher for the story task than for both word list tasks. Compared to story recall, word list recall correlated more consistently with motor severity and composite measures of processing speed, working memory, and executive functioning. These results support the classic view of fronto-subcortical contributions to memory in PD and suggest that executive deficits may influence word list recall more than story recall. We recommend a multi-componential memory battery in the neuropsychological assessment of DBS candidates to characterize both mesial temporal and frontal-executive memory processes. One should not rely solely on a word list task because patients exhibiting poor memory for word lists may perform better with stories and therefore deserve an interdisciplinary discussion for DBS surgery.

  20. The Wada Test: contributions to standardization of the stimulus for language and memory assessment

    Directory of Open Access Journals (Sweden)

    Mäder Maria Joana

    2004-01-01

    Full Text Available The Wada Test (WT is part of the presurgical evaluation for refractory epilepsy. The WT is not standardized and the protocols differ in important ways, including stimulus type of material presented for memory testing, timing of presentations and methods of assessment. The aim of this study was to contribute to establish parameters for a WT to Brazilian population investigating the performance of 100 normal subjects, without medication. Two parallel models were used based on Montreal Procedure adapted from Gail Risse's (MEG-MN,EUA protocol. The proportions of correct responses of normal subjects submitted to two parallel WT models were investigated and the two models were compared. The results showed that the two models are similar but significant differences among the stimulus type were observed. The results suggest that the stimulus type may influence the results of the WT and should be considered when constructing models and comparing different protocols.

  1. Application of Item Response Theory to Tests of Substance-related Associative Memory

    Science.gov (United States)

    Shono, Yusuke; Grenard, Jerry L.; Ames, Susan L.; Stacy, Alan W.

    2015-01-01

    A substance-related word association test (WAT) is one of the commonly used indirect tests of substance-related implicit associative memory and has been shown to predict substance use. This study applied an item response theory (IRT) modeling approach to evaluate psychometric properties of the alcohol- and marijuana-related WATs and their items among 775 ethnically diverse at-risk adolescents. After examining the IRT assumptions, item fit, and differential item functioning (DIF) across gender and age groups, the original 18 WAT items were reduced to 14- and 15-items in the alcohol- and marijuana-related WAT, respectively. Thereafter, unidimensional one- and two-parameter logistic models (1PL and 2PL models) were fitted to the revised WAT items. The results demonstrated that both alcohol- and marijuana-related WATs have good psychometric properties. These results were discussed in light of the framework of a unified concept of construct validity (Messick, 1975, 1989, 1995). PMID:25134051

  2. Testing the limits: cautions and concerns regarding the new Wechsler IQ and Memory scales.

    Science.gov (United States)

    Loring, David W; Bauer, Russell M

    2010-02-23

    The Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Memory Scale (WMS) are 2 of the most common psychological tests used in clinical care and research in neurology. Newly revised versions of both instruments (WAIS-IV and WMS-IV) have recently been published and are increasingly being adopted by the neuropsychology community. There have been significant changes in the structure and content of both scales, leading to the potential for inaccurate patient classification if algorithms developed using their predecessors are employed. There are presently insufficient clinical data in neurologic populations to insure their appropriate application to neuropsychological evaluations. We provide a perspective on these important new neuropsychological instruments, comment on the pressures to adopt these tests in the absence of an appropriate evidence base supporting their incremental validity, and describe the potential negative impact on both patient care and continuing research applications.

  3. Studies on laws of stress-magnetization based on magnetic memory testing technique

    Science.gov (United States)

    Ren, Shangkun; Ren, Xianzhi

    2018-03-01

    Metal magnetic memory (MMM) testing technique is a novel testing method which can early test stress concentration status of ferromagnetic components. Under the different maximum tensile stress, the relationship between the leakage magnetic field of at certain point of cold rolled steel specimen and the tensile stress was measured during the process of loading and unloading by repeated. It shows that when the maximum tensile stress is less than 610 MPa, the relationship between the magnetic induction intensity and the stress is linear; When the maximum tensile stress increase from 610 MPa to 653 MPa of yield point, the relationship between the magnetic induction intensity and the tensile becomes bending line. The location of the extreme point of the bending line will move rapidly from the position of smaller stress to the larger stress position, and the variation of magnetic induction intensity increases rapidly. When the maximum tensile stress is greater than the 653 MPa of yield point, the variation of the magnetic induction intensity remains large, and the position of the extreme point moves very little. In theoretical aspects, tensile stress is to be divided into ordered stress and disordered stress. In the stage of elastic stress, a microscopic model of the order stress magnetization is established, and the conclusions are in good agreement with the experimental data. In the plastic deformation stage, a microscopic model of disordered stress magnetization is established, and the conclusions are in good agreement with the experimental data, too. The research results can provide reference for the accurate quantitative detection and evaluation of metal magnetic memory testing technology.

  4. The role of retrieval mode and retrieval orientation in retrieval practice: insights from comparing recognition memory testing formats and restudying.

    Science.gov (United States)

    Gao, Chuanji; Rosburg, Timm; Hou, Mingzhu; Li, Bingbing; Xiao, Xin; Guo, Chunyan

    2016-12-01

    The effectiveness of retrieval practice for aiding long-term memory, referred to as the testing effect, has been widely demonstrated. However, the specific neurocognitive mechanisms underlying this phenomenon remain unclear. In the present study, we sought to explore the role of pre-retrieval processes at initial testing on later recognition performance by using event-related potentials (ERPs). Subjects studied two lists of words (Chinese characters) and then performed a recognition task or a source memory task, or restudied the word lists. At the end of the experiment, subjects received a final recognition test based on the remember-know paradigm. Behaviorally, initial testing (active retrieval) enhanced memory retention relative to restudying (passive retrieval). The retrieval mode at initial testing was indexed by more positive-going ERPs for unstudied items in the active-retrieval tasks than in passive retrieval from 300 to 900 ms. Follow-up analyses showed that the magnitude of the early ERP retrieval mode effect (300-500 ms) was predictive of the behavioral testing effect later on. In addition, the ERPs for correctly rejected new items during initial testing differed between the two active-retrieval tasks from 500 to 900 ms, and this ERP retrieval orientation effect predicted differential behavioral testing gains between the two active-retrieval conditions. Our findings confirm that initial testing promotes later retrieval relative to restudying, and they further suggest that adopting pre-retrieval processing in the forms of retrieval mode and retrieval orientation might contribute to these memory enhancements.

  5. Strength cues and blocking at test promote reliable within-list criterion shifts in recognition memory.

    Science.gov (United States)

    Hicks, Jason L; Starns, Jeffrey J

    2014-07-01

    In seven experiments, we explored the potential for strength-based, within-list criterion shifts in recognition memory. People studied a mix of target words, some presented four times (strong) and others studied once (weak). In Experiments 1, 2, 4A, and 4B, the test was organized into alternating blocks of 10, 20, or 40 trials. Each block contained lures intermixed with strong targets only or weak targets only. In strength-cued conditions, test probes appeared in a unique font color for strong and weak blocks. In the uncued conditions of Experiments 1 and 2, similar strength blocks were tested, but strength was not cued with font color. False alarms to lures were lower in blocks containing strong target words, as compared with lures in blocks containing weak targets, but only when strength was cued with font color. Providing test feedback in Experiment 2 did not alter these results. In Experiments 3A-3C, test items were presented in a random order (i.e., not blocked by strength). Of these three experiments, only one demonstrated a significant shift even though strength cues were provided. Overall, the criterion shift was larger and more reliable as block size increased, and the shift occurred only when strength was cued with font color. These results clarify the factors that affect participants' willingness to change their response criterion within a test list.

  6. Context-dependent effects of hippocampal damage on memory in the shock-probe test.

    Science.gov (United States)

    Lehmann, Hugo; Carfagnini, Adrienne; Yamin, Stephanie; Mumby, Dave G

    2005-01-01

    We assessed the role of the hippocampus in anterograde memory, using the shock-probe test. Rats with sham or neurotoxic lesions of the hippocampus were given a shock-probe acquisition session during which each time they contacted a probe they received a shock; 24 h later, the rats were given a second shock-probe session to test their retention, but in this instance the probe was not electrified. Rats were tested in either the same context as the one used during acquisition or in a different context. The hippocampal lesions impaired avoidance of the probe and burying on the retention test, suggesting that the lesions induced anterograde amnesia. However, the impairment was context dependent. The hippocampal lesions impaired avoidance only when the rats were tested in the context in which they received the conditioning. The results of the shock-probe test suggest that the anterograde amnesia following hippocampal lesions is due mainly to an inability to associate the context with the shock more than to an inability to associate the probe with shock. Copyright (c) 2004 Wiley-Liss, Inc.

  7. Thermo-magneto-elastoplastic coupling model of metal magnetic memory testing method for ferromagnetic materials

    Science.gov (United States)

    Shi, Pengpeng; Zhang, Pengcheng; Jin, Ke; Chen, Zhenmao; Zheng, Xiaojing

    2018-04-01

    Metal magnetic memory (MMM) testing (also known as micro-magnetic testing) is a new non-destructive electromagnetic testing method that can diagnose ferromagnetic materials at an early stage by measuring the MMM signal directly on the material surface. Previous experiments have shown that many factors affect MMM signals, in particular, the temperature, the elastoplastic state, and the complex environmental magnetic field. However, the fact that there have been only a few studies of either how these factors affect the signals or the physical coupling mechanisms among them seriously limits the industrial applications of MMM testing. In this paper, a nonlinear constitutive relation for a ferromagnetic material considering the influences of temperature and elastoplastic state is established under a weak magnetic field and is used to establish a nonlinear thermo-magneto-elastoplastic coupling model of MMM testing. Comparing with experimental data verifies that the proposed theoretical model can accurately describe the thermo-magneto-elastoplastic coupling influence on MMM signals. The proposed theoretical model can predict the MMM signals in a complex environment and so is expected to provide a theoretical basis for improving the degree of quantification in MMM testing.

  8. Effects of elevated CO2 on predator avoidance behaviour by reef fishes is not altered by experimental test water

    Directory of Open Access Journals (Sweden)

    Philip L. Munday

    2016-10-01

    Full Text Available Pioneering studies into the effects of elevated CO2 on the behaviour of reef fishes often tested high-CO2 reared fish using control water in the test arena. While subsequent studies using rearing treatment water (control or high CO2 in the test arena have confirmed the effects of high CO2 on a range of reef fish behaviours, a further investigation into the use of different test water in the experimental arena is warranted. Here, we used a fully factorial design to test the effect of rearing treatment water (control or high CO2 and experimental test water (control or high CO2 on antipredator responses of larval reef fishes. We tested antipredator behaviour in larval clownfish Amphiprion percula and ambon damselfish Pomacentrus amboinensis, two species that have been used in previous high CO2 experiments. Specifically, we tested if: (1 using control or high CO2 water in a two channel flume influenced the response of larval clownfish to predator odour; and (2 using control or high CO2 water in the test arena influenced the escape response of larval damselfish to a startle stimulus. Finally, (3 because the effects of high CO2 on fish behaviour appear to be caused by altered function of the GABA-A neurotransmitter we tested if antipredator behaviours were restored in clownfish treated with a GABA antagonist (gabazine in high CO2 water. Larval clownfish reared from hatching in control water (496 µatm strongly avoided predator cue whereas larval clownfish reared from hatching in high CO2 (1,022 µatm were attracted to the predator cue, as has been reported in previous studies. There was no effect on fish responses of using either control or high CO2 water in the flume. Larval damselfish reared for four days in high CO2 (1,051 µatm exhibited a slower response to a startle stimulus and slower escape speed compared with fish reared in control conditions (464 µatm. There was no effect of test water on escape responses. Treatment of high-CO2 reared

  9. Testing a Dynamic Field Account of Interactions between Spatial Attention and Spatial Working Memory

    Science.gov (United States)

    Johnson, Jeffrey S.; Spencer, John P.

    2016-01-01

    Studies examining the relationship between spatial attention and spatial working memory (SWM) have shown that discrimination responses are faster for targets appearing at locations that are being maintained in SWM, and that location memory is impaired when attention is withdrawn during the delay. These observations support the proposal that sustained attention is required for successful retention in SWM: if attention is withdrawn, memory representations are likely to fail, increasing errors. In the present study, this proposal is reexamined in light of a neural process model of SWM. On the basis of the model's functioning, we propose an alternative explanation for the observed decline in SWM performance when a secondary task is performed during retention: SWM representations drift systematically toward the location of targets appearing during the delay. To test this explanation, participants completed a color-discrimination task during the delay interval of a spatial recall task. In the critical shifting attention condition, the color stimulus could appear either toward or away from the memorized location relative to a midline reference axis. We hypothesized that if shifting attention during the delay leads to the failure of SWM representations, there should be an increase in the variance of recall errors but no change in directional error, regardless of the direction of the shift. Conversely, if shifting attention induces drift of SWM representations—as predicted by the model—there should be systematic changes in the pattern of spatial recall errors depending on the direction of the shift. Results were consistent with the latter possibility—recall errors were biased toward the location of discrimination targets appearing during the delay. PMID:26810574

  10. Testing a dynamic-field account of interactions between spatial attention and spatial working memory.

    Science.gov (United States)

    Johnson, Jeffrey S; Spencer, John P

    2016-05-01

    Studies examining the relationship between spatial attention and spatial working memory (SWM) have shown that discrimination responses are faster for targets appearing at locations that are being maintained in SWM, and that location memory is impaired when attention is withdrawn during the delay. These observations support the proposal that sustained attention is required for successful retention in SWM: If attention is withdrawn, memory representations are likely to fail, increasing errors. In the present study, this proposal was reexamined in light of a neural-process model of SWM. On the basis of the model's functioning, we propose an alternative explanation for the observed decline in SWM performance when a secondary task is performed during retention: SWM representations drift systematically toward the location of targets appearing during the delay. To test this explanation, participants completed a color discrimination task during the delay interval of a spatial-recall task. In the critical shifting-attention condition, the color stimulus could appear either toward or away from the midline reference axis, relative to the memorized location. We hypothesized that if shifting attention during the delay leads to the failure of SWM representations, there should be an increase in the variance of recall errors, but no change in directional errors, regardless of the direction of the shift. Conversely, if shifting attention induces drift of SWM representations-as predicted by the model-systematic changes in the patterns of spatial-recall errors should occur that would depend on the direction of the shift. The results were consistent with the latter possibility-recall errors were biased toward the locations of discrimination targets appearing during the delay.

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

    Science.gov (United States)

    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.

  12. Development and psychometric testing of a new instrument to measure the caring behaviour of nurses in Italian acute care settings.

    Science.gov (United States)

    Piredda, Michela; Ghezzi, Valerio; Fenizia, Elisa; Marchetti, Anna; Petitti, Tommasangelo; De Marinis, Maria Grazia; Sili, Alessandro

    2017-12-01

    To develop and psychometrically test the Italian-language Nurse Caring Behaviours Scale, a short measure of nurse caring behaviour as perceived by inpatients. Patient perceptions of nurses' caring behaviours are a predictor of care quality. Caring behaviours are culture-specific, but no measure of patient perceptions has previously been developed in Italy. Moreover, existing tools show unclear psychometric properties, are burdensome for respondents, or are not widely applicable. Instrument development and psychometric testing. Item generation included identifying and adapting items from existing measures of caring behaviours as perceived by patients. A pool of 28 items was evaluated for face validity. Content validity indexes were calculated for the resulting 15-item scale; acceptability and clarity were pilot tested with 50 patients. To assess construct validity, a sample of 2,001 consecutive adult patients admitted to a hospital in 2014 completed the scale and was split into two groups. Reliability was evaluated using nonlinear structural equation modelling coefficients. Measurement invariance was tested across subsamples. Item 15 loaded poorly in the exploratory factor analysis (n = 983) and was excluded from the final solution, positing a single latent variable with 14 indicators. This model fitted the data moderately. The confirmatory factor analysis (n = 1018) returned similar results. Internal consistency was excellent in both subsamples. Full scalar invariance was reached, and no significant latent mean differences were detected across subsamples. The new instrument shows reasonable psychometric properties and is a promising short and widely applicable measure of inpatient perceptions of nurse caring behaviours. © 2017 John Wiley & Sons Ltd.

  13. Effects of working memory capacity on metacognitive monitoring: A study of group differences using a listening span test

    Directory of Open Access Journals (Sweden)

    Mie eKomori

    2016-03-01

    Full Text Available Monitoring is an executive function of working memory that serves to update novel information, focusing attention on task-relevant targets, and eliminating task-irrelevant noise. The present research used a verbal working memory task to examine how working memory capacity limits affect monitoring. Participants performed a Japanese listening span test that included maintenance of target words and listening comprehension. On each trial, participants responded to the target word and then immediately estimated confidence in recall performance for that word (metacognitive judgment. The results confirmed significant differences in monitoring accuracy between high and low capacity groups in a multi-task situation. That is, confidence judgments were superior in high versus low capacity participants in terms of absolute accuracy and discrimination. The present research further investigated how memory load and interference affect underestimation of successful recall. The results indicated that the level of memory load that reduced word recall performance and led to an underconfidence bias varied according to participants’ memory capacity. In addition, irreverent information associated with incorrect true/ false decisions (secondary task and word recall within the current trial impaired monitoring accuracy in both participant groups. These findings suggest that inference from unsuccessful decisions only influences low, but not high, capacity participants. Therefore, monitoring accuracy, which requires high working memory capacity, improves metacognitive abilities by inhibiting task-irrelevant noise and focusing attention on detecting task-relevant targets or useful retrieval cues, which could improve actual cognitive performance.

  14. Effects of Working Memory Capacity on Metacognitive Monitoring: A Study of Group Differences Using a Listening Span Test.

    Science.gov (United States)

    Komori, Mie

    2016-01-01

    Monitoring is an executive function of working memory that serves to update novel information, focusing attention on task-relevant targets, and eliminating task-irrelevant noise. The present research used a verbal working memory task to examine how working memory capacity limits affect monitoring. Participants performed a Japanese listening span test that included maintenance of target words and listening comprehension. On each trial, participants responded to the target word and then immediately estimated confidence in recall performance for that word (metacognitive judgment). The results confirmed significant differences in monitoring accuracy between high and low capacity groups in a multi-task situation. That is, confidence judgments were superior in high vs. low capacity participants in terms of absolute accuracy and discrimination. The present research further investigated how memory load and interference affect underestimation of successful recall. The results indicated that the level of memory load that reduced word recall performance and led to an underconfidence bias varied according to participants' memory capacity. In addition, irrelevant information associated with incorrect true/ false decisions (secondary task) and word recall within the current trial impaired monitoring accuracy in both participant groups. These findings suggest that interference from unsuccessful decisions only influences low, but not high, capacity participants. Therefore, monitoring accuracy, which requires high working memory capacity, improves metacognitive abilities by inhibiting task-irrelevant noise and focusing attention on detecting task-relevant targets or useful retrieval cues, which could improve actual cognitive performance.

  15. Determination of strength behaviour of slope supported by vegetated crib walls using centrifuge model testing

    Science.gov (United States)

    Sudan Acharya, Madhu

    2010-05-01

    The crib retaining structures made of wooden/bamboo logs with live plants inside are called vegetative crib walls which are now becoming popular due to their advantages over conventional civil engineering walls. Conventionally, wooden crib walls were dimensioned based on past experiences. At present, there are several guidelines and design standards for machine finished wooden crib walls, but only few guidelines for the design and construction of vegetative log crib walls are available which are generally not sufficient for an economic engineering design of such walls. Analytical methods are generally used to determine the strength of vegetated crib retaining walls. The crib construction is analysed statically by satisfying the condition of static equilibrium with acceptable level of safety. The crib wall system is checked for internal and external stability using conventional monolithic and silo theories. Due to limitations of available theories, the exact calculation of the strength of vegetated wooden/bamboo crib wall cannot be made in static calculation. Therefore, experimental measurements are generally done to verify the static analysis. In this work, a model crib construction (1:20) made of bamboo elements is tested in the centrifuge machine to determine the strength behaviour of the slope supported by vegetated crib retaining wall. A geotechnical centrifuge is used to conduct model tests to study geotechnical problems such as the strength, stiffness and bearing capacity of different structures, settlement of embankments, stability of slopes, earth retaining structures etc. Centrifuge model testing is particularly well suited to modelling geotechnical events because the increase in gravitational force creates stresses in the model that are equivalent to the much larger prototype and hence ensures that the mechanisms of ground movements observed in the tests are realistic. Centrifuge model testing provides data to improve our understanding of basic mechanisms

  16. Early age mechanical behaviour of 3D printed concrete : Numerical modelling and experimental testing

    NARCIS (Netherlands)

    Wolfs, R.J.M.; Bos, F.P.; Salet, T.A.M.

    2018-01-01

    A numerical model was developed to analyse the mechanical behaviour of fresh, 3D printed concrete, in the range of 0 to 90 min after material deposition. The model was based on a time-dependent Mohr-Coulomb failure criterion and linear stress-strain behaviour up to failure. An experimental program,

  17. Interaction between morphine and noradrenergic system of basolateral amygdala on anxiety and memory in the elevated plus-maze test based on a test-retest paradigm.

    Science.gov (United States)

    Valizadegan, Farhad; Oryan, Shahrbanoo; Nasehi, Mohammad; Zarrindast, Mohammad Reza

    2013-05-01

    The amygdala is the key brain structure for anxiety and emotional memory storage. We examined the involvement of β-adrenoreceptors in the basolateral amygdala (BLA) and their interaction with morphine in modulating these behaviors. The elevated plus-maze has been employed for investigating anxiety and memory. Male Wistar rats were used for this test. We injected morphine (4, 5, and 6 mg/kg) intraperitoneally, while salbutamol (albuterol) (1, 2, and 4 μg/rat) and propranolol (1, 2, and 4 μg/rat) were injected into the BLA. Open- arms time percentage (%OAT), open- arms entry percentage (%OAE), and locomotor activity were determined by this behavioral test. Retention was tested 24 hours later. Intraperitoneal injection of morphine (6 mg/kg) had an anxiolytic-like effect and improvement of memory. The highest dose of salbutamol decreased the anxiety parameters in test session and improved the memory in retest session. Coadministration of salbutamol and ineffective dose of morphine presenting anxiolytic response. In this case, the memory was improved. Intra-BLA administration of propranolol (4 μg/rat) decreased %OAT in the test session, while had no effect on memory formation. Coadministration of propranolol and morphine (6 mg/kg) showed an increase in %OAT. There was not any significant change in the above- mentioned parameter in the retest session. Coadministration of morphine and propranolol with the effective dose of salbutamol showed that propranolol could reverse anxiolytic-like effect. We found that opioidergic and β-adrenergic systems have the same effects on anxiety and memory in the BLA; but these effects are independent of each other.

  18. Demographically corrected norms for African Americans and Caucasians on the Hopkins Verbal Learning Test-Revised, Brief Visuospatial Memory Test-Revised, Stroop Color and Word Test, and Wisconsin Card Sorting Test 64-Card Version.

    Science.gov (United States)

    Norman, Marc A; Moore, David J; Taylor, Michael; Franklin, Donald; Cysique, Lucette; Ake, Chris; Lazarretto, Deborah; Vaida, Florin; Heaton, Robert K

    2011-08-01

    Memory and executive functioning are two important components of clinical neuropsychological (NP) practice and research. Multiple demographic factors are known to affect performance differentially on most NP tests, but adequate normative corrections, inclusive of race/ethnicity, are not available for many widely used instruments. This study compared demographic contributions for widely used tests of verbal and visual learning and memory (Brief Visual Memory Test-Revised, Hopkins Verbal Memory Test-Revised) and executive functioning (Stroop Color and Word Test, Wisconsin Card Sorting Test-64) in groups of healthy Caucasians (n = 143) and African Americans (n = 103). Demographic factors of age, education, gender, and race/ethnicity were found to be significant factors on some indices of all four tests. The magnitude of demographic contributions (especially age) was greater for African Americans than for Caucasians on most measures. New, demographically corrected T-score formulas were calculated for each race/ethnicity. The rates of NP impairment using previously published normative standards significantly overestimated NP impairment in African Americans. Utilizing the new demographic corrections developed and presented herein, NP impairment rates were comparable between the two race/ethnicities and were unrelated to the other demographic characteristics (age, education, gender) in either race/ethnicity group. Findings support the need to consider extended demographic contributions to neuropsychological test performance in clinical and research settings.

  19. Visual Working Memory and Perception Speed of 3- to 6-Year-Old Children Tested with a Matrix Film Battery Test

    Science.gov (United States)

    Pittorf, Martin L.; Lehmann, Wolfgang; Huckauf, Anke

    2014-01-01

    In this study the visual working memory (VWM) and perception speed of 60 children between the ages of three and six years were tested with an age-based, easy-to-handle Matrix Film Battery Test (reliability R?=?0.71). It was thereby affirmed that the VWM is age dependent (correlation coefficient r?=?0.66***) as expected. Furthermore, a significant…

  20. The Study of Externalizing and Internalizing Behaviours in Greek, Russian, Indian, and Chinese Children Using the Fairy Tale Test

    Science.gov (United States)

    Savina, Elena; Coulacoglou, Carina; Sanyal, Nilanjana; Zhang, Jianxin

    2012-01-01

    The present study investigated externalizing and internalizing behaviours in Greek (n = 599), Russian (n = 596), Indian (n = 571), and Chinese (n = 376) 7- to 12-year-old children. The Fairy Tale Test was used to measure impulsive and motivated aggression, fear of aggression, anxiety, and depression. The results indicated culture-specific patterns…

  1. A longitudinal study of hepatitis C virus testing and infection status notification on behaviour change in people who inject drugs

    NARCIS (Netherlands)

    Spelman, T.; Morris, M. D.; Zang, G.; Rice, T.; Page, K.; Maher, L.; Lloyd, A.; Grebely, J.; Dore, G. J.; Kim, A. Y.; Shoukry, N. H.; Hellard, M.; Bruneau, J.; Cox, Andrea L.; Lauer, Georg; McGovern, Barbara H.; Prins, Maria; Hahn, Judy; Shiboski, Stephen; Mirzazadeh, Ali; Alavi, Maryam; Bouchard, Rachel; Evans, Jennifer; Grady, Bart; Aneja, Jasneet; Sacks-Davis, Rachel; Teutsch, Suzy; White, Bethany; Wells, Brittany; Applegate, Tanya; Matthews, Gail; Yeung, Barbara; Schinkel, Janke; Prince, Leslie Erin; Roy, Elise; Bates, Anna; Enriquez, Jarliene; Chow, Sammy; McCredie, Luke; Aitken, Campbell; Doyle, Joseph

    2015-01-01

    Background Hepatitis C virus (HCV) testing and counselling have the potential to impact individual behaviour and transmission dynamics at the population level. Evidence of the impact of an HCV-positive status notification on injection risk reduction is limited. The objective of our study was to (1)

  2. Sexual behaviours, perception of risk of HIV infection, and factors associated with attending HIV post-test counselling in Ethiopia

    NARCIS (Netherlands)

    Sahlu, T.; Kassa, E.; Agonafer, T.; Tsegaye, A.; Rinke de Wit, T.; Gebremariam, H.; Doorly, R.; Spijkerman, I.; Yeneneh, H.; Coutinho, R. A.; Fontanet, A. L.

    1999-01-01

    OBJECTIVES: To describe sexual behaviours, perception of risk of HIV infection, and factors associated with attending HIV post-test counselling (PTC) among Ethiopian adults. METHODS: Data on socio-demographic characteristics, knowledge of HIV infection, sexual history, medical examination, and HIV

  3. Wedge Splitting Test and Inverse Analysis on Fracture Behaviour of Fiber Reinforced and Regular High Performance Concretes

    DEFF Research Database (Denmark)

    Hodicky, Kamil; Hulin, Thomas; Schmidt, Jacob Wittrup

    2014-01-01

    The fracture behaviour of three fiber reinforced and regular HPC (high performance concretes) is presented in this paper. Two mixes are based on optimization of HPC whereas the third mix was a commercial mix developed by CONTEC ApS (Denmark). The wedge splitting test setup with 48 cubical specimens...

  4. Failure modes induced by natural radiation environments on DRAM memories: study, test methodology and mitigation technique

    International Nuclear Information System (INIS)

    Bougerol, A.

    2011-05-01

    DRAMs are frequently used in space and aeronautic systems. Their sensitivity to cosmic radiations have to be known in order to satisfy reliability requirements for critical applications. These evaluations are traditionally done with particle accelerators. However, devices become more complex with technology integration. Therefore new effects appear, inducing longer and more expensive tests. There is a complementary solution: the pulsed laser, which triggers similar effects as particles. Thanks to these two test tools, main DRAM radiation failure modes were studied: SEUs (Single Event Upset) in memory blocks, and SEFIs (Single Event Functional Interrupt) in peripheral circuits. This work demonstrates the influence of test patterns on SEU and SEFI sensitivities depending on technology used. In addition, this study identifies the origin of the most frequent type of SEFIs. Moreover, laser techniques were developed to quantify sensitive surfaces of the different effects. This work led to a new test methodology for industry, in order to optimize test cost and efficiency using both pulsed laser beams and particle accelerators. Finally, a new fault tolerant technique is proposed: based on DRAM cell radiation immunity when discharged, this technique allows to correct all bits of a logic word. (author)

  5. Individual and combined effects of enactment and testing on memory for action phrases.

    Science.gov (United States)

    Kubik, Veit; Söderlund, Hedvig; Nilsson, Lars-Göran; Jönsson, Fredrik U

    2014-01-01

    We investigated the individual and combined effects of enactment and testing on memory for action phrases to address whether both study techniques commonly promote item-specific processing. Participants (N = 112) were divided into four groups (n = 28). They either exclusively studied 36 action phrases (e.g., "lift the glass") or both studied and cued-recalled them in four trials. During study trials participants encoded the action phrases either by motorically performing them, or by reading them aloud, and they took final verb-cued recall tests over 18-min and 1-week retention intervals. A testing effect was demonstrated for action phrases, however, only when they were verbally encoded, and not when they were enacted. Similarly, enactive (relative to verbal) encoding reduced the rate of forgetting, but only when the action phrases were exclusively studied, and not when they were also tested. These less-than-additive effects of enactment and testing on the rate of forgetting, as well as on long-term retention, support the notion that both study techniques effectively promote item-specific processing that can only be marginally increased further by combining them.

  6. Behavioral testing of mice exposed to intermediate frequency magnetic fields indicates mild memory impairment.

    Directory of Open Access Journals (Sweden)

    Kajal Kumari

    Full Text Available Human exposure to intermediate frequency magnetic fields (MF is increasing due to applications like electronic article surveillance systems and induction heating cooking hobs. However, limited data is available on their possible health effects. The present study assessed behavioral and histopathological consequences of exposing mice to 7.5 kHz MF at 12 or 120 μT for 5 weeks. No effects were observed on body weight, spontaneous activity, motor coordination, level of anxiety or aggression. In the Morris swim task, mice in the 120 μT group showed less steep learning curve than the other groups, but did not differ from controls in their search bias in the probe test. The passive avoidance task indicated a clear impairment of memory over 48 h in the 120 μT group. No effects on astroglial activation or neurogenesis were observed in the hippocampus. The mRNA expression of brain-derived neurotrophic factor did not change but expression of the proinflammatory cytokine tumor necrosis factor alpha mRNA was significantly increased in the 120 μT group. These findings suggest that 7.5 kHz MF exposure may lead to mild learning and memory impairment, possibly through an inflammatory reaction in the hippocampus.

  7. Tests to characterize the behaviour of natural stone in contact with water

    Directory of Open Access Journals (Sweden)

    Vielba Cuerpo, C.

    2002-09-01

    Full Text Available This paper presents an experimental analysis of the stone behaviour in contact with water in the different construction uses. In any of these cases is analyse how the water penetrates into the material. As a result of the study the need of modification of the UNE test standards is concluded. It is proposed a procedure to determinate the material's properties and a method to compare and analyse the result obtained that keep into consideration the climate factors. The method have been applied to sandstone of Villamayor (Spain showing its utility in the analysis of the stone properties.

    Se expone la necesidad de revisión de las normas UNE de ensayo para la determinación del comportamiento frente al agua de las rocas porosas teniendo en cuenta las formas de exposición que suponen las distintas aplicaciones constructivas y los mecanismos de penetración del agua que en cada caso operan. Se propone para ello una sistemática de ensayos y un método comparado de análisis de resultados basado en la consideración de los factores climatológicos. La utilidad del método se ilustra con un ejemplo de aplicación al estudio de la Arenisca de Villamayor

  8. A dual-docking microfluidic cell migration assay (D2-Chip) for testing neutrophil chemotaxis and the memory effect.

    Science.gov (United States)

    Yang, Ke; Wu, Jiandong; Xu, Guoqing; Xie, Dongxue; Peretz-Soroka, Hagit; Santos, Susy; Alexander, Murray; Zhu, Ling; Zhang, Michael; Liu, Yong; Lin, Francis

    2017-04-18

    Chemotaxis is a classic mechanism for guiding cell migration and an important topic in both fundamental cell biology and health sciences. Neutrophils are a widely used model to study eukaryotic cell migration and neutrophil chemotaxis itself can lead to protective or harmful immune actions to the body. While much has been learnt from past research about how neutrophils effectively navigate through a chemoattractant gradient, many interesting questions remain unclear. For example, while it is tempting to model neutrophil chemotaxis using the well-established biased random walk theory, the experimental proof was challenged by the cell's highly persistent migrating nature. A special experimental design is required to test the key predictions from the random walk model. Another question that has interested the cell migration community for decades concerns the existence of chemotactic memory and its underlying mechanism. Although chemotactic memory has been suggested in various studies, a clear quantitative experimental demonstration will improve our understanding of the migratory memory effect. Motivated by these questions, we developed a microfluidic cell migration assay (so-called dual-docking chip or D 2 -Chip) that can test both the biased random walk model and the memory effect for neutrophil chemotaxis on a single chip enabled by multi-region gradient generation and dual-region cell alignment. Our results provide experimental support for the biased random walk model and chemotactic memory for neutrophil chemotaxis. Quantitative data analyses provide new insights into neutrophil chemotaxis and memory by making connections to entropic disorder, cell morphology and oscillating migratory response.

  9. Comparison of the neural correlates of retrieval success in tests of cued recall and recognition memory.

    Science.gov (United States)

    Okada, Kayoko; Vilberg, Kaia L; Rugg, Michael D

    2012-03-01

    The neural correlates of successful retrieval on tests of word stem recall and recognition memory were compared. In the recall test, subjects viewed word stems, half of which were associated with studied items and half with unstudied items, and for each stem attempted to recall a corresponding study word. In the recognition test, old/new judgments were made on old and new words. The neural correlates of successful retrieval were identified by contrasting activity elicited by correctly endorsed test items. Old > new effects common to the two tasks were found in medial and lateral parietal and right entorhinal cortex. Common new > old effects were identified in medial and left frontal cortex, and left anterior intra-parietal sulcus. Greater old > new effects were evident for cued recall in inferior parietal regions abutting those demonstrating common effects, whereas larger new > old effects were found for recall in left frontal cortex and the anterior cingulate. New > old effects were also found for the recall task in right lateral anterior prefrontal cortex, where they were accompanied by old > new effects during recognition. It is concluded that successful recall and recognition are associated with enhanced activity in a common set of recollection-sensitive parietal regions, and that the greater activation in these regions during recall reflects the greater dependence of that task on recollection. Larger new > old effects during recall are interpreted as reflections of the greater opportunity for iterative retrieval attempts when retrieval cues are partial rather than copy cues. Copyright © 2011 Wiley Periodicals, Inc.

  10. Effects of Saccade Induced Retrieval Enhancement on conceptual and perceptual tests of explicit & implicit memory.

    Science.gov (United States)

    Parker, Andrew; Powell, Daniel; Dagnall, Neil

    2018-03-01

    The effects of saccadic horizontal (bilateral) eye movements upon tests of both conceptual and perceptual forms of explicit and implicit memory were investigated. Participants studied a list of words and were then assigned to one of four test conditions: conceptual explicit, conceptual implicit, perceptual explicit, or perceptual implicit. Conceptual tests comprised category labels with either explicit instructions to recall corresponding examples from the study phase (category-cued recall), or implicit instructions to generate any corresponding examples that spontaneously came to mind (category-exemplar generation). Perceptual tests comprised of word-fragments with either explicit instructions to complete these with study items (word-fragment-cued recall), or implicit instructions to complete each fragment with the first word that simply 'popped to mind' (word-fragment completion). Just prior to retrieval, participants were required to engage in 30 s of bilateral vs. no eye movements. Results revealed that saccadic horizontal eye movements enhanced performance in only the conceptual explicit condition, indicating that Saccade-Induced Retrieval Enhancement is a joint function of conceptual and explicit retrieval mechanisms. Findings are discussed from both a cognitive and neuropsychological perspective, in terms of their potential functional and neural underpinnings. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Validation of the Danish Addenbrooke's Cognitive Examination as a screening test in a memory clinic.

    Science.gov (United States)

    Stokholm, Jette; Vogel, Asmus; Johannsen, Peter; Waldemar, Gunhild

    2009-01-01

    Addenbrooke's Cognitive Examination (ACE) is a cognitive screening test developed to detect dementia. It has been validated in several countries. Validation studies have predominantly included patients with various degrees of dementia and healthy controls. The aim of this study was to evaluate the Danish version of ACE as a screening test for early dementia in an outpatient memory clinic. Further, we wanted to investigate the ability of the ACE to discriminate patients with early Alzheimer's disease (AD) from patients with depression. 78 patients with mild AD (MMSE >or=20), 30 non-demented patients diagnosed with depression (originally referred for evaluation of cognitive symptoms), and 63 healthy volunteers, all between 60 and 85 years of age, were included. All patients were given the ACE as a supplement to the standard diagnostic work-up. The cut-off points for optimal trade-off between sensitivity and specificity for ACE were 85/86 (sensitivity 0.99, specificity 0.94). When these cut-off points were applied to the group of depressive patients, the specificity dropped to 0.64, indicating a great overlap in individual test scores for demented and depressed patients. The optimal cut-off points for ACE found in this Danish study were close to what is reported in most other European studies. The great overlap in ACE scores for demented and depressed patients emphasize that test scores must be interpreted with great caution when used in diagnostic work-up.

  12. Large scale testing of nitinol shape memory alloy devices for retrofitting of bridges

    International Nuclear Information System (INIS)

    Johnson, Rita; Emmanuel Maragakis, M; Saiid Saiidi, M; Padgett, Jamie E; DesRoches, Reginald

    2008-01-01

    A large scale testing program was conducted to determine the effects of shape memory alloy (SMA) restrainer cables on the seismic performance of in-span hinges of a representative multiple-frame concrete box girder bridge subjected to earthquake excitations. Another objective of the study was to compare the performance of SMA restrainers to that of traditional steel restrainers as restraining devices for reducing hinge displacement and the likelihood of collapse during earthquakes. The results of the tests show that SMA restrainers performed very well as restraining devices. The forces in the SMA and steel restrainers were comparable. However, the SMA restrainer cables had minimal residual strain after repeated loading and exhibited the ability to undergo many cycles with little strength and stiffness degradation. In addition, the hysteretic damping that was observed in the larger ground accelerations demonstrated the ability of the materials to dissipate energy. An analytical study was conducted to assess the anticipated seismic response of the test setup and evaluate the accuracy of the analytical model. The results of the analytical simulation illustrate that the analytical model was able to match the responses from the experimental tests, including peak stresses, strains, forces, and hinge openings

  13. Item Response Theory Analyses of the Cambridge Face Memory Test (CFMT)

    Science.gov (United States)

    Cho, Sun-Joo; Wilmer, Jeremy; Herzmann, Grit; McGugin, Rankin; Fiset, Daniel; Van Gulick, Ana E.; Ryan, Katie; Gauthier, Isabel

    2014-01-01

    We evaluated the psychometric properties of the Cambridge face memory test (CFMT; Duchaine & Nakayama, 2006). First, we assessed the dimensionality of the test with a bi-factor exploratory factor analysis (EFA). This EFA analysis revealed a general factor and three specific factors clustered by targets of CFMT. However, the three specific factors appeared to be minor factors that can be ignored. Second, we fit a unidimensional item response model. This item response model showed that the CFMT items could discriminate individuals at different ability levels and covered a wide range of the ability continuum. We found the CFMT to be particularly precise for a wide range of ability levels. Third, we implemented item response theory (IRT) differential item functioning (DIF) analyses for each gender group and two age groups (Age ≤ 20 versus Age > 21). This DIF analysis suggested little evidence of consequential differential functioning on the CFMT for these groups, supporting the use of the test to compare older to younger, or male to female, individuals. Fourth, we tested for a gender difference on the latent facial recognition ability with an explanatory item response model. We found a significant but small gender difference on the latent ability for face recognition, which was higher for women than men by 0.184, at age mean 23.2, controlling for linear and quadratic age effects. Finally, we discuss the practical considerations of the use of total scores versus IRT scale scores in applications of the CFMT. PMID:25642930

  14. Design and testing of shape memory alloy actuation mechanism for flapping wing micro unmanned aerial vehicles

    Science.gov (United States)

    Kamaruzaman, N. F.; Abdullah, E. J.

    2017-12-01

    Shape memory alloy (SMA) actuator offers great solution for aerospace applications with low weight being its most attractive feature. A SMA actuation mechanism for the flapping micro unmanned aerial vehicle (MAV) is proposed in this study, where SMA material is the primary system that provides the flapping motion to the wings. Based on several established design criteria, a design prototype has been fabricated to validate the design. As a proof of concept, an experiment is performed using an electrical circuit to power the SMA actuator to evaluate the flapping angle. During testing, several problems have been observed and their solutions for future development are proposed. Based on the experiment, the average recorded flapping wing angle is 14.33° for upward deflection and 12.12° for downward deflection. This meets the required design criteria and objective set forth for this design. The results prove the feasibility of employing SMA actuators in flapping wing MAV.

  15. Task relevance modulates successful retrieval effects during explicit and implicit memory tests.

    Science.gov (United States)

    Elman, Jeremy A; Shimamura, Arthur P

    2011-05-01

    The successful retrieval effect refers to greater activation for items identified as old compared to those identified as new. This effect is particularly apparent in the ventral posterior parietal cortex (vPPC), though its functional properties remain unclear. In two experiments, we assessed the activation for old and new items during explicit and implicit tests of memory. In Experiment 1, significant effects were observed during explicit recognition performance and during an implicit lexical decision task. In both tasks, determining mnemonic status provides relevant information to task goals. Experiment 2 included a second implicit task in which determining mnemonic status was not relevant (color discrimination task). In this case, vPPC activation did not distinguish between old and new items. These findings suggest that automatic or implicit processes can drive retrieval-related activation in the vPPC, though such processes are gated by stimulus relevancy and task goals. Copyright © 2011 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2017-07-01

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

  17. An extended continuum model considering optimal velocity change with memory and numerical tests

    Science.gov (United States)

    Qingtao, Zhai; Hongxia, Ge; Rongjun, Cheng

    2018-01-01

    In this paper, an extended continuum model of traffic flow is proposed with the consideration of optimal velocity changes with memory. The new model's stability condition and KdV-Burgers equation considering the optimal velocities change with memory are deduced through linear stability theory and nonlinear analysis, respectively. Numerical simulation is carried out to study the extended continuum model, which explores how optimal velocity changes with memory affected velocity, density and energy consumption. Numerical results show that when considering the effects of optimal velocity changes with memory, the traffic jams can be suppressed efficiently. Both the memory step and sensitivity parameters of optimal velocity changes with memory will enhance the stability of traffic flow efficiently. Furthermore, numerical results demonstrates that the effect of optimal velocity changes with memory can avoid the disadvantage of historical information, which increases the stability of traffic flow on road, and so it improve the traffic flow stability and minimize cars' energy consumptions.

  18. The late negative episodic memory effect: the effect of recapitulating study details at test.

    Science.gov (United States)

    Friedman, David; Cycowicz, Yael M; Bersick, Michael

    2005-05-01

    An hypothesis concerning mnemonic function suggests that perceptual details of previously experienced episodes are retrieved from the cortices that initially processed that information during the encoding phase. Cycowicz et al. [Cycowicz, Y.M., Friedman, D. and Snodgrass, J.G., Remembering the color of objects: an ERP investigation of source memory, Cereb Cortex, 11 (2001) 322-334.] have interpreted the presence of a late negative episodic memory (EM) effect, maximal over parieto-occipital scalp, as a brain signature of the search for and/or retrieval/evaluation of the specific perceptual source-specifying attributes (i.e., color) of pictures in the visual cortical regions that were recruited during the encoding of that information. The present study assessed the validity of this hypothesis. Twelve participants studied pictures outlined in red or green and were subsequently tested with inclusion (i.e., item; old or new regardless of color) and exclusion (i.e., source; same color, different color/new judgments) tasks. In both, old pictures were presented either in the same color as at study or in the alternate color. A late negative, parieto-occipital EM effect was of much larger amplitude in the source compared to the item task. It was of similar magnitude to correctly recognized pictures whose colors were identical at study and test relative to those whose colors changed, and was not modulated by the success or failure of the source retrieval. These data run counter to the initial hypothesis that the late negative EM effect reflects the search for and/or retrieval of specific perceptual attributes such as color. Rather, the late negative EM effect may reflect the search for and/or retrieval/evaluation of more general source-specifying information in the cortical regions that initially processed the stimuli.

  19. The quadratic relationship between difficulty of intelligence test items and their correlations with working memory

    Directory of Open Access Journals (Sweden)

    Tomasz eSmoleń

    2015-08-01

    Full Text Available Fluid intelligence (Gf is a crucial cognitive ability that involves abstract reasoning in order to solve novel problems. Recent research demonstrated that Gf strongly depends on the individual effectiveness of working memory (WM. We investigated a popular claim that if the storage capacity underlay the WM-Gf correlation, then such a correlation should increase with an increasing number of items or rules (load in a Gf test. As often no such link is observed, on that basis the storage-capacity account is rejected, and alternative accounts of Gf (e.g., related to executive control or processing speed are proposed. Using both analytical inference and numerical simulations, we demonstrated that the load-dependent change in correlation is primarily a function of the amount of floor/ceiling effect for particular items. Thus, the item-wise WM correlation of a Gf test depends on its overall difficulty, and the difficulty distribution across its items. When the early test items yield huge ceiling, but the late items do not approach floor, that correlation will increase throughout the test. If the early items locate themselves between ceiling and floor, but the late items approach floor, the respective correlation will decrease. For a hallmark Gf test, the Raven test, whose items span from ceiling to floor, the quadratic relationship is expected, and it was shown empirically using a large sample and two types of WMC tasks. In consequence, no changes in correlation due to varying WM/Gf load, or lack of them, can yield an argument for or against any theory of WM/Gf. Moreover, as the mathematical properties of the correlation formula make it relatively immune to ceiling/floor effects for overall moderate correlations, only minor changes (if any in the WM-Gf correlation should be expected for many psychological tests.

  20. The quadratic relationship between difficulty of intelligence test items and their correlations with working memory.

    Science.gov (United States)

    Smolen, Tomasz; Chuderski, Adam

    2015-01-01

    Fluid intelligence (Gf) is a crucial cognitive ability that involves abstract reasoning in order to solve novel problems. Recent research demonstrated that Gf strongly depends on the individual effectiveness of working memory (WM). We investigated a popular claim that if the storage capacity underlay the WM-Gf correlation, then such a correlation should increase with an increasing number of items or rules (load) in a Gf-test. As often no such link is observed, on that basis the storage-capacity account is rejected, and alternative accounts of Gf (e.g., related to executive control or processing speed) are proposed. Using both analytical inference and numerical simulations, we demonstrated that the load-dependent change in correlation is primarily a function of the amount of floor/ceiling effect for particular items. Thus, the item-wise WM correlation of a Gf-test depends on its overall difficulty, and the difficulty distribution across its items. When the early test items yield huge ceiling, but the late items do not approach floor, that correlation will increase throughout the test. If the early items locate themselves between ceiling and floor, but the late items approach floor, the respective correlation will decrease. For a hallmark Gf-test, the Raven-test, whose items span from ceiling to floor, the quadratic relationship is expected, and it was shown empirically using a large sample and two types of WMC tasks. In consequence, no changes in correlation due to varying WM/Gf load, or lack of them, can yield an argument for or against any theory of WM/Gf. Moreover, as the mathematical properties of the correlation formula make it relatively immune to ceiling/floor effects for overall moderate correlations, only minor changes (if any) in the WM-Gf correlation should be expected for many psychological tests.

  1. Lactobacillus helveticus-fermented milk improves learning and memory in mice.

    Science.gov (United States)

    Ohsawa, Kazuhito; Uchida, Naoto; Ohki, Kohji; Nakamura, Yasunori; Yokogoshi, Hidehiko

    2015-07-01

    To investigate the effects of Calpis sour milk whey, a Lactobacillus helveticus-fermented milk product, on learning and memory. We evaluated improvement in scopolamine-induced memory impairment using the spontaneous alternation behaviour test, a measure of short-term memory. We also evaluated learning and working memory in mice using the novel object recognition test, which does not involve primary reinforcement (food or electric shocks). A total of 195 male ddY mice were used in the spontaneous alternation behaviour test and 60 in the novel object recognition test. Forced orally administered Calpis sour milk whey powder (200 and 2000 mg/kg) significantly improved scopolamine-induced cognitive impairments (P memory (2000 mg/kg; P learning and memory in healthy human subjects; however, human clinical studies are necessary.

  2. Declarative memory.

    Science.gov (United States)

    Riedel, Wim J; Blokland, Arjan

    2015-01-01

    Declarative Memory consists of memory for events (episodic memory) and facts (semantic memory). Methods to test declarative memory are key in investigating effects of potential cognition-enhancing substances--medicinal drugs or nutrients. A number of cognitive performance tests assessing declarative episodic memory tapping verbal learning, logical memory, pattern recognition memory, and paired associates learning are described. These tests have been used as outcome variables in 34 studies in humans that have been described in the literature in the past 10 years. Also, the use of episodic tests in animal research is discussed also in relation to the drug effects in these tasks. The results show that nutritional supplementation of polyunsaturated fatty acids has been investigated most abundantly and, in a number of cases, but not all, show indications of positive effects on declarative memory, more so in elderly than in young subjects. Studies investigating effects of registered anti-Alzheimer drugs, cholinesterase inhibitors in mild cognitive impairment, show positive and negative effects on declarative memory. Studies mainly carried out in healthy volunteers investigating the effects of acute dopamine stimulation indicate enhanced memory consolidation as manifested specifically by better delayed recall, especially at time points long after learning and more so when drug is administered after learning and if word lists are longer. The animal studies reveal a different picture with respect to the effects of different drugs on memory performance. This suggests that at least for episodic memory tasks, the translational value is rather poor. For the human studies, detailed parameters of the compositions of word lists for declarative memory tests are discussed and it is concluded that tailored adaptations of tests to fit the hypothesis under study, rather than "off-the-shelf" use of existing tests, are recommended.

  3. The effects of a reminder of underwater trauma on behaviour and memory-related mechanisms in the rat dentate gyrus.

    Science.gov (United States)

    Ardi, Ziv; Ritov, Gilad; Lucas, Morgan; Richter-Levin, Gal

    2014-04-01

    Intrusive re-experiencing is a core symptom in post-traumatic stress disorder (PTSD), often triggered by contextual cues associated with the trauma. It is not yet clear if intrusive re-experiencing is only the result, or whether it may contribute to the establishment of PTSD following acute stress. This study aimed at examining the impact of an underwater trauma (UWT) reminder on anxiety-like behaviour and on neuronal activity and plasticity in the hippocampus and the amygdala. Sprague-Dawley rats were exposed to UWT and 24 h later were re-exposed to the context. The effects on behaviour, activation of the amygdala (BLA) and dentate gyrus (DG), and on long-term potentiation (LTP) and local circuit activity (frequency-dependent inhibition (FDI) and paired-pulse inhibition (PPI)) in the DG were assessed. The exposure to UWT by itself resulted in increased anxiety behaviour in the open field, together with increased PPI. Upon exposure to the UWT reminder, an additional increase in anxiety was also observed in the EPM and in FDI. Moreover, reminder exposure resulted in impaired DG LTP and a significant BLA extracellular-signal-regulated kinases (ERK) 2 activation. In conclusion, these observed effects of exposure to a trauma reminder, following the exposure to the initial trauma, might be associated with the progression of trauma-related pathologies and the development of related disorders.

  4. Attention, interpretation, and memory biases in subclinical depression: a proof-of-principle test of the combined cognitive biases hypothesis.

    Science.gov (United States)

    Everaert, Jonas; Duyck, Wouter; Koster, Ernst H W

    2014-04-01

    Emotional biases in attention, interpretation, and memory are viewed as important cognitive processes underlying symptoms of depression. To date, there is a limited understanding of the interplay among these processing biases. This study tested the dependence of memory on depression-related biases in attention and interpretation. Subclinically depressed and nondepressed participants completed a computerized version of the scrambled sentences test (measuring interpretation bias) while their eye movements were recorded (measuring attention bias). This task was followed by an incidental free recall test of previously constructed interpretations (measuring memory bias). Path analysis revealed a good fit for the model in which selective orienting of attention was associated with interpretation bias, which in turn was associated with a congruent bias in memory. Also, a good fit was observed for a path model in which biases in the maintenance of attention and interpretation were associated with memory bias. Both path models attained a superior fit compared with path models without the theorized functional relations among processing biases. These findings enhance understanding of how mechanisms of attention and interpretation regulate what is remembered. As such, they offer support for the combined cognitive biases hypothesis or the notion that emotionally biased cognitive processes are not isolated mechanisms but instead influence each other. Implications for theoretical models and emotion regulation across the spectrum of depressive symptoms are discussed.

  5. A simple spatial working memory and attention test on paired symbols shows developmental deficits in schizophrenia patients.

    Science.gov (United States)

    Song, Wei; Zhang, Kai; Sun, Jinhua; Ma, Lina; Jesse, Forrest Fabian; Teng, Xiaochun; Zhou, Ying; Bao, Hechen; Chen, Shiqing; Wang, Shuai; Yang, Beimeng; Chu, Xixia; Ding, Wenhua; Du, Yasong; Cheng, Zaohuo; Wu, Bin; Chen, Shanguang; He, Guang; He, Lin; Chen, Xiaoping; Li, Weidong

    2013-01-01

    People with neuropsychiatric disorders such as schizophrenia often display deficits in spatial working memory and attention. Evaluating working memory and attention in schizophrenia patients is usually based on traditional tasks and the interviewer's judgment. We developed a simple Spatial Working Memory and Attention Test on Paired Symbols (SWAPS). It takes only several minutes to complete, comprising 101 trials for each subject. In this study, we tested 72 schizophrenia patients and 188 healthy volunteers in China. In a healthy control group with ages ranging from 12 to 60, the efficiency score (accuracy divided by reaction time) reached a peak in the 20-27 age range and then declined with increasing age. Importantly, schizophrenia patients failed to display this developmental trend in the same age range and adults had significant deficits compared to the control group. Our data suggests that this simple Spatial Working Memory and Attention Test on Paired Symbols can be a useful tool for studies of spatial working memory and attention in neuropsychiatric disorders.

  6. A Simple Spatial Working Memory and Attention Test on Paired Symbols Shows Developmental Deficits in Schizophrenia Patients

    Directory of Open Access Journals (Sweden)

    Wei Song

    2013-01-01

    Full Text Available People with neuropsychiatric disorders such as schizophrenia often display deficits in spatial working memory and attention. Evaluating working memory and attention in schizophrenia patients is usually based on traditional tasks and the interviewer’s judgment. We developed a simple Spatial Working Memory and Attention Test on Paired Symbols (SWAPS. It takes only several minutes to complete, comprising 101 trials for each subject. In this study, we tested 72 schizophrenia patients and 188 healthy volunteers in China. In a healthy control group with ages ranging from 12 to 60, the efficiency score (accuracy divided by reaction time reached a peak in the 20–27 age range and then declined with increasing age. Importantly, schizophrenia patients failed to display this developmental trend in the same age range and adults had significant deficits compared to the control group. Our data suggests that this simple Spatial Working Memory and Attention Test on Paired Symbols can be a useful tool for studies of spatial working memory and attention in neuropsychiatric disorders.

  7. The Cambridge Face Memory Test for Children (CFMT-C): a new tool for measuring face recognition skills in childhood.

    Science.gov (United States)

    Croydon, Abigail; Pimperton, Hannah; Ewing, Louise; Duchaine, Brad C; Pellicano, Elizabeth

    2014-09-01

    Face recognition ability follows a lengthy developmental course, not reaching maturity until well into adulthood. Valid and reliable assessments of face recognition memory ability are necessary to examine patterns of ability and disability in face processing, yet there is a dearth of such assessments for children. We modified a well-known test of face memory in adults, the Cambridge Face Memory Test (Duchaine & Nakayama, 2006, Neuropsychologia, 44, 576-585), to make it developmentally appropriate for children. To establish its utility, we administered either the upright or inverted versions of the computerised Cambridge Face Memory Test - Children (CFMT-C) to 401 children aged between 5 and 12 years. Our results show that the CFMT-C is sufficiently sensitive to demonstrate age-related gains in the recognition of unfamiliar upright and inverted faces, does not suffer from ceiling or floor effects, generates robust inversion effects, and is capable of detecting difficulties in face memory in children diagnosed with autism. Together, these findings indicate that the CFMT-C constitutes a new valid assessment tool for children's face recognition skills. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Behavioural research on human working memory: mixing qualitative and quantitative methods (Investigación conductual sobre memoria de trabajo: Integrando métodos cualitativos y cuantitativos

    Directory of Open Access Journals (Sweden)

    María de los Angeles Bacigalupe

    2013-12-01

    Full Text Available ABSTRACT: The long lasting opposition between qualitative and quantitative methods for studying behaviour has been overridden by interdisciplinary work in which methods can be combined to approach animal and human behaviour, thus contributing to drawing rigorous and useful conclusions. We show an example of this by combining a quasi-experimental design and descriptive methods to study working memory for the resolution of a spatial problem task (the Tower of Hanoi in a neuropsychiatric hospital inpatient with amnesia and executive deficits. Results from the quasi-experiment showed that the patient acquired strategies to solve the task with a high level of efficiency (F3/35 = 7, 19, p < .01. Qualitatively speaking, the patient developed more than one strategy to solve the problem, which indicates the presence of learning based on working memory. In the light of these findings, we discuss issues of mixed methods research and suggest the importance of developing mixed methods to study behaviour. RESUMEN: La oposición duradera entre métodos cualitativos y cuantitativos para estudiar el comportamiento ha sido anulada por el trabajo interdisciplinario en que los métodos pueden combinarse para enfocar el comportamiento humano y animal, contribuyendo así a obtener conclusiones útiles y rigurosas. Se presenta una muestra, combinando métodos descriptivos y un diseño cuasiexperimental para estudiar la memoria de trabajo en la resolución de una tarea de problema espacial (la Torre de Hanoi, en un paciente internado en un hospital neuropsiquiátrico con amnesia y déficit ejecutivo. Resultados del cuasiexperimento demostraron que el paciente adquirió estrategias para resolver la tarea con un alto nivel de eficiencia (F3/35 = 7, 19, p < .01. Cualitativamente el paciente desarrolló más de una estrategia para resolver el problema, lo cual indica la presencia de aprendizaje basado en memoria de trabajo. A la luz de estos resultados, se discuten m

  9. The effect of age-at-testing on verbal memory among children following severe traumatic brain injury.

    Science.gov (United States)

    Silberg, Tamar; Ahonniska-Assa, Jaana; Levav, Miriam; Eliyahu, Roni; Peleg-Pilowsky, Tamar; Brezner, Amichai; Vakil, Eli

    2016-01-01

    Memory deficits are a common sequelae following childhood traumatic brain injury (TBI), which often have serious implications on age-related academic skills. The current study examined verbal memory performance using the Rey Auditory Verbal Learning Test (RAVLT) in a pediatric TBI sample. Verbal memory abilities as well as the effect of age at-testing on performance were examined. A sample of 67 children following severe TBI (age average = 12.3 ± 2.74) and 67 matched controls were evaluated using the RAVLT. Age effect at assessment was examined using two age groups: above and below 12 years of age during evaluation. Differences between groups were examined via the 9 RAVLT learning trials and the 7 composite scores conducted out of them. Children following TBI recalled significantly less words than controls on all RAVLT trials and had significantly lower scores on all composite scores. However, all of these scores fell within the low average range. Further analysis revealed significantly lower than average performance among the older children (above 12 years), while scores of the younger children following TBI fell within average limits. To conclude, verbal memory deficits among children following severe TBI demonstrate an age-at-testing effect with more prominent problems occurring above 12 years at the time of evaluation. Yet, age-appropriate performance among children below 12 years of age may not accurately describe memory abilities at younger ages following TBI. It is therefore recommended that clinicians address child's age at testing and avoid using a single test as an indicator of verbal memory functioning post TBI.

  10. How does additional diagnostic testing influence the initial diagnosis in patients with cognitive complaints in a memory clinic setting?

    Science.gov (United States)

    Meijs, Anouk P; Claassen, Jurgen A H R; Rikkert, Marcel G M Olde; Schalk, Bianca W M; Meulenbroek, Olga; Kessels, Roy P C; Melis, René J F

    2015-01-01

    patients suspected of dementia frequently undergo additional diagnostic testing (e.g. brain imaging or neuropsychological assessment) after standard clinical assessment at a memory clinic. This study investigates the use of additional testing in an academic outpatient memory clinic and how it influences the initial diagnosis. the initial diagnosis after standard clinical assessment (history, laboratory tests, cognitive screening and physical and neurological examination) and the final diagnosis after additional testing of 752 memory clinic patients were collected. We specifically registered if, and what type of, additional testing was requested. additional testing was performed in 518 patients (69%), 67% of whom underwent magnetic resonance imaging, 45% had neuropsychological assessment, 14% had cerebrospinal fluid analysis and 49% had (combinations of) other tests. This led to a modification of the initial diagnosis in 17% of the patients. The frequency of change was highest in patients with an initial non-Alzheimer's disease (AD) dementia diagnosis (54%, compared with 11 and 14% in patients with AD and 'no dementia'; P testing 44% was diagnosed with AD, 9% with non-AD dementia and 47% with 'no dementia'. additional testing should especially be considered in non-AD patients. In the large group of patients with an initial AD or 'no dementia' diagnosis, additional tests have little diagnostic impact and may perhaps be used with more restraint. © The Author 2014. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Effects of degraded sensory input on memory for speech: behavioral data and a test of biologically constrained computational models.

    Science.gov (United States)

    Piquado, Tepring; Cousins, Katheryn A Q; Wingfield, Arthur; Miller, Paul

    2010-12-13

    Poor hearing acuity reduces memory for spoken words, even when the words are presented with enough clarity for correct recognition. An "effortful hypothesis" suggests that the perceptual effort needed for recognition draws from resources that would otherwise be available for encoding the word in memory. To assess this hypothesis, we conducted a behavioral task requiring immediate free recall of word-lists, some of which contained an acoustically masked word that was just above perceptual threshold. Results show that masking a word reduces the recall of that word and words prior to it, as well as weakening the linking associations between the masked and prior words. In contrast, recall probabilities of words following the masked word are not affected. To account for this effect we conducted computational simulations testing two classes of models: Associative Linking Models and Short-Term Memory Buffer Models. Only a model that integrated both contextual linking and buffer components matched all of the effects of masking observed in our behavioral data. In this Linking-Buffer Model, the masked word disrupts a short-term memory buffer, causing associative links of words in the buffer to be weakened, affecting memory for the masked word and the word prior to it, while allowing links of words following the masked word to be spared. We suggest that these data account for the so-called "effortful hypothesis", where distorted input has a detrimental impact on prior information stored in short-term memory. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Effect of genetic homogeneity on behavioural variability in an object recognition test in cloned Göttingen minipigs

    DEFF Research Database (Denmark)

    Søndergaard, Lene Vammen; Herskin, Mette S.; Ladewig, Jan

    2012-01-01

    effects of genetic homogeneity on variability of cloned minipigs compared with non-cloned controls regarding behavioural variables in a cognitive test, namely the spontaneous object recognition test. Significant differences in the variability between the cloned and control pigs were found in five out...... was numerically greater for the control group compared to the cloned group, indicating that variation may be less in cloned animals, but not demonstrable with the small group size of the present study (n = 6 for each of the two groups tested). Overall, this study failed to show unambiguously that variability......The number of animals used in research should be limited as much as possible. Among cloned animals, genetic variation is minimal and to the extent that behaviour is genetically determined inter-individual variability is expected to be higher among naturally bred animals. However, the cloning...

  13. Comparison of sliding friction and wear behaviour of overhead conveyor steels tested under dry and lubrication conditions

    International Nuclear Information System (INIS)

    Castro-Regal, G.; Fernandez-Vicente, A.; Martinez, M. A.

    2005-01-01

    The sliding friction and wear behaviour of different steel qualities were investigated with and without lubrication conditions. Steel qualities tested are normally used in the overhead conveyor system of many industrial fields, like the automotive sector. Sliding wear tests have been conducted by means of a pin-on-disk machine. A 100Cr6 steel similar to that used within the overhead conveyor trolleys has been employed as a pin. Friction coefficient values obtained under lubrication conditions were three times smaller than those obtained without lubrication. The mechanism that controls wear behaviour under lubrication conditions is an abrasive one and the wear values obtained are almost worthless. On the other hand, mechanism controlling wear during non lubrication tests, was a combination of abrasion and adhesion. (Author) 20 refs

  14. Dietary choline supplementation in adult rats improves performance on a test of recognition memory.

    Science.gov (United States)

    Moreno, Hayarelis; Hall, Geoffrey; Gallo, Milagros; de Brugada, Isabel

    2018-04-22

    In two experiments adult rats (aged at least 6 months at the start of the procedure) received a diet enriched with added choline for a period of 10 weeks; control subjects were maintained on a standard diet during this time. All rats then underwent the spontaneous object recognition (SOR) procedure in which they were exposed to a pair of objects and then tested, after a retention interval, to a display with one object changed. Exploration of the changed object indicates retention and use of information acquired during the exposure phase. All subjects showed retention with a 24-h interval (Experiments 1 and 2) and when retested after a further 24 h (Experiment 1). But when tested for the first time after a 48-h interval (Experiment 2), control subjects showed no evidence of retention, exploring both objects equally, whereas those given the dietary supplement continued to show a preference for the changed object. This supports the conclusion that dietary choline supplementation can enhance performance on a task regarded as a test of declarative memory, and will do so even when the supplementations is given in adulthood. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Face recognition performance of individuals with Asperger syndrome on the Cambridge Face Memory Test.

    Science.gov (United States)

    Hedley, Darren; Brewer, Neil; Young, Robyn

    2011-12-01

    Although face recognition deficits in individuals with Autism Spectrum Disorder (ASD), including Asperger syndrome (AS), are widely acknowledged, the empirical evidence is mixed. This in part reflects the failure to use standardized and psychometrically sound tests. We contrasted standardized face recognition scores on the Cambridge Face Memory Test (CFMT) for 34 individuals with AS with those for 42, IQ-matched non-ASD individuals, and age-standardized scores from a large Australian cohort. We also examined the influence of IQ, autistic traits, and negative affect on face recognition performance. Overall, participants with AS performed significantly worse on the CFMT than the non-ASD participants and when evaluated against standardized test norms. However, while 24% of participants with AS presented with severe face recognition impairment (>2 SDs below the mean), many individuals performed at or above the typical level for their age: 53% scored within +/- 1 SD of the mean and 9% demonstrated superior performance (>1 SD above the mean). Regression analysis provided no evidence that IQ, autistic traits, or negative affect significantly influenced face recognition: diagnostic group membership was the only significant predictor of face recognition performance. In sum, face recognition performance in ASD is on a continuum, but with average levels significantly below non-ASD levels of performance. Copyright © 2011, International Society for Autism Research, Wiley-Liss, Inc.

  16. Fast neutron irradiation tests of flash memories used in space environment at the ISIS spallation neutron source

    Directory of Open Access Journals (Sweden)

    C. Andreani

    2018-02-01

    Full Text Available This paper presents a neutron accelerated study of soft errors in advanced electronic devices used in space missions, i.e. Flash memories performed at the ChipIr and VESUVIO beam lines at the ISIS spallation neutron source. The two neutron beam lines are set up to mimic the space environment spectra and allow neutron irradiation tests on Flash memories in the neutron energy range above 10 MeV and up to 800 MeV. The ISIS neutron energy spectrum is similar to the one occurring in the atmospheric as well as in space and planetary environments, with intensity enhancements varying in the range 108- 10 9 and 106- 10 7 respectively. Such conditions are suitable for the characterization of the atmospheric, space and planetary neutron radiation environments, and are directly applicable for accelerated tests of electronic components as demonstrated here in benchmark measurements performed on flash memories.

  17. Fast neutron irradiation tests of flash memories used in space environment at the ISIS spallation neutron source

    Science.gov (United States)

    Andreani, C.; Senesi, R.; Paccagnella, A.; Bagatin, M.; Gerardin, S.; Cazzaniga, C.; Frost, C. D.; Picozza, P.; Gorini, G.; Mancini, R.; Sarno, M.

    2018-02-01

    This paper presents a neutron accelerated study of soft errors in advanced electronic devices used in space missions, i.e. Flash memories performed at the ChipIr and VESUVIO beam lines at the ISIS spallation neutron source. The two neutron beam lines are set up to mimic the space environment spectra and allow neutron irradiation tests on Flash memories in the neutron energy range above 10 MeV and up to 800 MeV. The ISIS neutron energy spectrum is similar to the one occurring in the atmospheric as well as in space and planetary environments, with intensity enhancements varying in the range 108- 10 9 and 106- 10 7 respectively. Such conditions are suitable for the characterization of the atmospheric, space and planetary neutron radiation environments, and are directly applicable for accelerated tests of electronic components as demonstrated here in benchmark measurements performed on flash memories.

  18. [Effect of concreteness of target words on verbal working memory: an evaluation using Japanese version of reading span test].

    Science.gov (United States)

    Kondo, H; Osaka, N

    2000-04-01

    Effects of concreteness and representation mode (kanji/hiragana) of target words on working memory during reading was tested using Japanese version of reading span test (RST), developed by Osaka and Osaka (1994). Concreteness and familiarity of target words and difficulty of sentences were carefully controlled. The words with high concreteness resulted in significantly higher RST scores, which suggests the high efficiency of working memory in processing these words. The results suggest that high concrete noun-words associated with visual clues consume less working memory capacity during reading. The effect of representation mode is different between subjects with high-RST and low-RST scores. Characteristic of the high concrete words that may be responsible for the effectiveness of processing are discussed.

  19. Strengthened effective connectivity underlies transfer of working memory training to tests of short-term memory and attention.

    Science.gov (United States)

    Kundu, Bornali; Sutterer, David W; Emrich, Stephen M; Postle, Bradley R

    2013-05-15

    Although long considered a natively endowed and fixed trait, working memory (WM) ability has recently been shown to improve with intensive training. What remains controversial and poorly understood, however, are the neural bases of these training effects and the extent to which WM training gains transfer to other cognitive tasks. Here we present evidence from human electrophysiology (EEG) and simultaneous transcranial magnetic stimulation and EEG that the transfer of WM training to other cognitive tasks is supported by changes in task-related effective connectivity in frontoparietal and parieto-occipital networks that are engaged by both the trained and transfer tasks. One consequence of this effect is greater efficiency of stimulus processing, as evidenced by changes in EEG indices of individual differences in short-term memory capacity and in visual search performance. Transfer to search-related activity provides evidence that something more fundamental than task-specific strategy or stimulus-specific representations has been learned. Furthermore, these patterns of training and transfer highlight the role of common neural systems in determining individual differences in aspects of visuospatial cognition.

  20. Perceived parental rearing behaviours, responsibility attitudes and life events as predictors of obsessive compulsive symptomatology: test of a cognitive model.

    Science.gov (United States)

    Haciomeroglu, Bikem; Karanci, A Nuray

    2014-11-01

    It is important to investigate the role of cognitive, developmental and environmental factors in the development and maintenance of Obsessive Compulsive Symptomatology (OCS). The main objective of this study was to examine the vulnerability factors of OCS in a non-clinical sample. On the basis of Salkovskis' cognitive model of OCD, the study aimed to investigate the role of perceived parental rearing behaviours, responsibility attitudes, and life events in predicting OCS. Furthermore, the mediator role of responsibility attitudes in the relationship between perceived parental rearing behaviours and OCS was examined. Finally, the specificity of these variables to OCS was evaluated by examining the relationship of the same variables with depression and trait anxiety. A total of 300 university students (M = 19.55±1.79) were administered the Padua Inventory-Washington State University Revision, Responsibility Attitudes Scale, s-EMBU (My memories of upbringing), Life Events Inventory for University Students, Beck Depression Inventory, and State-Trait Anxiety Inventory-Trait Form. Regression analysis revealed that perceived mother overprotection, responsibility attitudes and life events significantly predicted OCS. Furthermore, responsibility attitudes mediated the relationship between perceived mother overprotection and OCS. The predictive role of perceived mother overprotection and the mediator role responsibility attitudes were OCS specific. The findings of the present study supported that perceived mother over-protection as a developmental vulnerability factor significantly contributed to the explanation of a cognitive vulnerability factor (namely responsibility attitudes), and perceived maternal overprotection had its predictive role for OCS through responsibility attitudes.