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Sample records for groton maze learning

  1. Expanding Learning through Mazes and Visual Imagery.

    Science.gov (United States)

    Currant, Nanda

    1982-01-01

    The author speculates on the mythic symbolism of the maze and describes her work with learning disabled students who responded favorably to mazes, especially to visualization tasks involving mazes. (CL)

  2. Clustering for Improved Learning in Maze Traversal Problem

    CERN Document Server

    White, Eddie

    2009-01-01

    The maze traversal problem (finding the shortest distance to the goal from any position in a maze) has been an interesting challenge in computational intelligence. Recent work has shown that the cellular simultaneous recurrent neural network (CSRN) can solve this problem for simple mazes. This thesis focuses on exploiting relevant information about the maze to improve learning and decrease the training time for the CSRN to solve mazes. Appropriate variables are identified to create useful clusters using relevant information. The CSRN was next modified to allow for an additional external input. With this additional input, several methods were tested and results show that clustering the mazes improves the overall learning of the traversal problem for the CSRN.

  3. Convergent validity and sex differences in healthy elderly adults for performance on 3D virtual reality navigation learning and 2D hidden maze tasks.

    Science.gov (United States)

    Tippett, William J; Lee, Jang-Han; Mraz, Richard; Zakzanis, Konstantine K; Snyder, Peter J; Black, Sandra E; Graham, Simon J

    2009-04-01

    This study assessed the convergent validity of a virtual environment (VE) navigation learning task, the Groton Maze Learning Test (GMLT), and selected traditional neuropsychological tests performed in a group of healthy elderly adults (n = 24). The cohort was divided equally between males and females to explore performance variability due to sex differences, which were subsequently characterized and reported as part of the analysis. To facilitate performance comparisons, specific "efficiency" scores were created for both the VE navigation task and the GMLT. Men reached peak performance more rapidly than women during VE navigation and on the GMLT and significantly outperformed women on the first learning trial in the VE. Results suggest reasonable convergent validity across the VE task, GMLT, and selected neuropsychological tests for assessment of spatial memory.

  4. Improved maze learning through early music exposure in rats.

    Science.gov (United States)

    Rauscher, F H; Robinson, K D; Jens, J J

    1998-07-01

    Rats were exposed in utero plus 60 days post-partum to either complex music (Mozart Sonata (k. 448)), minimalist music (a Philip Glass composition), white noise or silence, and were then tested for five days, three trials per day, in a multiple T-maze. By Day 3, the rats exposed to the Mozart work completed the maze more rapidly and with fewer errors than the rats assigned to the other groups. The difference increased in magnitude through Day 5. This suggests that repeated exposure to complex music induces improved spatial-temporal learning in rats, resembling results found in humans. Taken together with studies of enrichment-induced neural plasticity, these results suggest a similar neurophysiological mechanism for the effects of music on spatial learning in rats and humans.

  5. Maze learning by a hybrid brain-computer system

    Science.gov (United States)

    Wu, Zhaohui; Zheng, Nenggan; Zhang, Shaowu; Zheng, Xiaoxiang; Gao, Liqiang; Su, Lijuan

    2016-09-01

    The combination of biological and artificial intelligence is particularly driven by two major strands of research: one involves the control of mechanical, usually prosthetic, devices by conscious biological subjects, whereas the other involves the control of animal behaviour by stimulating nervous systems electrically or optically. However, to our knowledge, no study has demonstrated that spatial learning in a computer-based system can affect the learning and decision making behaviour of the biological component, namely a rat, when these two types of intelligence are wired together to form a new intelligent entity. Here, we show how rule operations conducted by computing components contribute to a novel hybrid brain-computer system, i.e., ratbots, exhibit superior learning abilities in a maze learning task, even when their vision and whisker sensation were blocked. We anticipate that our study will encourage other researchers to investigate combinations of various rule operations and other artificial intelligence algorithms with the learning and memory processes of organic brains to develop more powerful cyborg intelligence systems. Our results potentially have profound implications for a variety of applications in intelligent systems and neural rehabilitation.

  6. Water maze learning and hippocampal synaptic plasticity in streptozotocin diabetic rats: effects of insulin treatment

    NARCIS (Netherlands)

    Gispen, W.H.; Biessels, G.J.; Kamal, A.; Urban, I.J.A.; Spruijt, B.M.; Erkelens, D.W.

    1998-01-01

    Streptozotocin-diabetic rats express deficits in water maze learning and hippocampal synaptic plasticity. The present study examined whether these deficits could be prevented and/or reversed with insulin treatment. In addition, the water maze learning deficit in diabetic rats was further characteriz

  7. Comparing Exploration Strategies for Q-learning in Random Stochastic Mazes

    NARCIS (Netherlands)

    Tijsma, Arryon; Drugan, Madalina; Wiering, Marco

    2016-01-01

    Balancing the ratio between exploration and exploitation is an important problem in reinforcement learning. This paper evaluates four different exploration strategies combined with Q-learning using random stochastic mazes to investigate their performances. We will compare: UCB-1, softmax,

  8. A maze learning comparison of Elman, long short-term memory, and Mona neural networks.

    Science.gov (United States)

    Portegys, Thomas E

    2010-03-01

    This study compares the maze learning performance of three artificial neural network architectures: an Elman recurrent neural network, a long short-term memory (LSTM) network, and Mona, a goal-seeking neural network. The mazes are networks of distinctly marked rooms randomly interconnected by doors that open probabilistically. The mazes are used to examine two important problems related to artificial neural networks: (1) the retention of long-term state information and (2) the modular use of learned information. For the former, mazes impose a context learning demand: at the beginning of the maze, an initial door choice forms a context that must be remembered until the end of the maze, where the same numbered door must be chosen again in order to reach the goal. For the latter, the effect of modular and non-modular training is examined. In modular training, the door associations are trained in separate trials from the intervening maze paths, and only presented together in testing trials. All networks performed well on mazes without the context learning requirement. The Mona and LSTM networks performed well on context learning with non-modular training; the Elman performance degraded as the task length increased. Mona also performed well for modular training; both the LSTM and Elman networks performed poorly with modular training.

  9. Second Language Learning with the Story Maze Task: Examining the Training Effect of Weaving through Stories

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    Enkin, Elizabeth

    2016-01-01

    The maze task is a psycholinguistic experimental procedure that measures real-time incremental sentence processing. The task has recently been tested as a language learning tool with promising results. Therefore, the present study examines the merits of a contextualized version of this task: the story maze. The findings are consistent with…

  10. Using the Morris water maze to assess spatial learning and memory in weanling mice.

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    Barnhart, Christopher D; Yang, Dongren; Lein, Pamela J

    2015-01-01

    Mouse models have been indispensable for elucidating normal and pathological processes that influence learning and memory. A widely used method for assessing these cognitive processes in mice is the Morris water maze, a classic test for examining spatial learning and memory. However, Morris water maze studies with mice have principally been performed using adult animals, which preclude studies of critical neurodevelopmental periods when the cellular and molecular substrates of learning and memory are formed. While weanling rats have been successfully trained in the Morris water maze, there have been few attempts to test weanling mice in this behavioral paradigm even though mice offer significant experimental advantages because of the availability of many genetically modified strains. Here, we present experimental evidence that weanling mice can be trained in the Morris water maze beginning on postnatal day 24. Maze-trained weanling mice exhibit significant improvements in spatial learning over the training period and results of the probe trial indicate the development of spatial memory. There were no sex differences in the animals' performance in these tasks. In addition, molecular biomarkers of synaptic plasticity are upregulated in maze-trained mice at the transcript level. These findings demonstrate that the Morris water maze can be used to assess spatial learning and memory in weanling mice, providing a potentially powerful experimental approach for examining the influence of genes, environmental factors and their interactions on the development of learning and memory.

  11. Using the Morris water maze to assess spatial learning and memory in weanling mice.

    Directory of Open Access Journals (Sweden)

    Christopher D Barnhart

    Full Text Available Mouse models have been indispensable for elucidating normal and pathological processes that influence learning and memory. A widely used method for assessing these cognitive processes in mice is the Morris water maze, a classic test for examining spatial learning and memory. However, Morris water maze studies with mice have principally been performed using adult animals, which preclude studies of critical neurodevelopmental periods when the cellular and molecular substrates of learning and memory are formed. While weanling rats have been successfully trained in the Morris water maze, there have been few attempts to test weanling mice in this behavioral paradigm even though mice offer significant experimental advantages because of the availability of many genetically modified strains. Here, we present experimental evidence that weanling mice can be trained in the Morris water maze beginning on postnatal day 24. Maze-trained weanling mice exhibit significant improvements in spatial learning over the training period and results of the probe trial indicate the development of spatial memory. There were no sex differences in the animals' performance in these tasks. In addition, molecular biomarkers of synaptic plasticity are upregulated in maze-trained mice at the transcript level. These findings demonstrate that the Morris water maze can be used to assess spatial learning and memory in weanling mice, providing a potentially powerful experimental approach for examining the influence of genes, environmental factors and their interactions on the development of learning and memory.

  12. Exhumed from thought: basal ganglia and response learning in the plus-maze.

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    Packard, Mark G

    2009-04-12

    The plus-maze apparatus figured prominently in the historical debate between cognitive and stimulus-response habit learning theorists concerned with the fundamental question of "what" animals learn. An important feature of this task is that variants of the training procedure can be arranged to allow for an assessment of the relative use of cognitive/place or habit/response learning mechanisms. This brief review describes findings from several neurobiological studies published primarily over the past decade that have re-introduced the plus-maze to investigate the role of the dorsal striatum in learning and memory. Converging evidence from research using brain lesion, pharmacological, and molecular/genetic approaches is described supporting the hypothesis that the dorsolateral striatum plays a selective role in response learning in the plus-maze. Within a multiple systems framework of memory organization, factors that can influence the relative use of place and response learning in the plus-maze are also considered, including the nature of the visual environment, reinforcement/training parameters, and emotional state of the organism. Response learning in the plus-maze may be considered an exemplar task useful for investigating the neurobiological bases of dorsal striatal involvement in habit learning and memory. This mnemonic function of the dorsal striatum generalizes across several sensory modalities and mammalian species, including humans.

  13. Comparing Exploration Strategies for Q-learning in Random Stochastic Mazes

    NARCIS (Netherlands)

    Tijsma, Arryon; Drugan, Madalina; Wiering, Marco

    2016-01-01

    Balancing the ratio between exploration and exploitation is an important problem in reinforcement learning. This paper evaluates four different exploration strategies combined with Q-learning using random stochastic mazes to investigate their performances. We will compare: UCB-1, softmax, epsilon-gr

  14. The scientific learning approach using multimedia-based maze game to improve learning outcomes

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    Setiawan, Wawan; Hafitriani, Sarah; Prabawa, Harsa Wara

    2016-02-01

    The objective of curriculum 2013 is to improve the quality of education in Indonesia, which leads to improving the quality of learning. The scientific approach and supported empowerment media is one approach as massaged of curriculum 2013. This research aims to design a labyrinth game based multimedia and apply in the scientific learning approach. This study was conducted in one of the Vocational School in Subjects of Computer Network on 2 (two) classes of experimental and control. The method used Mix Method Research (MMR) which combines qualitative in multimedia design, and quantitative in the study of learning impact. The results of a survey showed that the general of vocational students like of network topology material (68%), like multimedia (74%), and in particular, like interactive multimedia games and flash (84%). Multimediabased maze game developed good eligibility based on media and material aspects of each value 840% and 82%. Student learning outcomes as a result of using a scientific approach to learning with a multimediabased labyrinth game increase with an average of gain index about (58%) and higher than conventional multimedia with index average gain of 0.41 (41%). Based on these results the scientific approach to learning by using multimediabased labyrinth game can improve the quality of learning and increase understanding of students. Multimedia of learning based labyrinth game, which developed, got a positive response from the students with a good qualification level (75%).

  15. Place and Response Learning in the Open-field Tower Maze.

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    Lipatova, Olga; Campolattaro, Matthew M; Toufexis, Donna J; Mabry, Erin A

    2015-10-28

    This protocol describes how the Open-field Tower Maze (OFTM) paradigm is used to study spatial learning in rodents. This maze is especially useful for examining how rats learn to use a place- or response-learning to successfully navigate in an open-field arena. Additionally, this protocol describes how the OFTM differs from other behavioral maze paradigms that are commonly used to study spatial learning in rodents. The OFTM described in this article was adapted from the one previously described by Cole, Clipperton, and Walt (2007). Specifically, the OFTM was created to test spatial learning in rodents without the experimenter having to consider how "stress" might play a role as a confounding variable. Experiments have shown that stress-alone can significantly affect cognitive function(1). The representative results section contains data from an experiment that used the OFTM to examine the effects of estradiol treatment on place- and response-learning in adult female Sprague Dawley rats(2). Future studies will be designed to examine the role of the hippocampus and striatum in place- and response-learning in the OFTM.

  16. Fractal dimensions: A new paradigm to assess spatial memory and learning using Morris water maze.

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    Singh, Surjeet; Kaur, Harpreet; Sandhir, Rajat

    2016-02-15

    Morris water maze has been widely used for analysis of cognitive functions and relies on the time taken by animal to find the platform i.e. escape latency as a parameter to quantify spatial memory and learning. However, escape latency is confounded by swimming speed which is not necessarily a cognitive factor. Rather, path length may be a more appropriate and reliable parameter to assess spatial learning. This paper presents fractal dimension as a new paradigm to assess spatial memory and learning in animals. Male wistar rats were administrated with pentylenetetrazole and scopolamine to induce chronic epilepsy and dementia respectively. Fractal dimension of the random path followed by the animals on Morris water maze was analyzed and statistically compared among different experimental groups; the results suggest that fractal dimension is more reliable and accurate parameter to assess cognitive deficits compared to escape latency. Thus, the present study suggests that fractal dimensions could be used as an independent parameter to assess spatial memory and learning in animals using Morris water maze.

  17. Effects of rolipram and zaprinast on learning and memory in the Morris water maze and radial arm maze tests in naive mice.

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    Akar, F; Mutlu, O; Celikyurt, I K; Ulak, G; Erden, F; Bektas, E; Tanyeri, P

    2015-02-01

    Inhibition of phosphodiesterase 5 (PDE) improved recognition memory and counteracted spatial learning impairment induced by nitric oxide synthase (NOS) inhibition in recent studies. Aim of this study was to investigate effects of rolipram, a PDE4 inhibitor and zaprinast, a PDE5 inhibitor, on learning and memory in Morris water maze (MWM) and radial arm maze (RAM) tests in naive mice. Male Balb-c mice were treated subchronically with zaprinast (3 and 10 mg/kg) and rolipram (0.05 and 0.1 mg/kg) for 6 days in the MWM test and acutely before the retention trial of radial arm maze test. Rolipram (0.05 and 0.1 mg/kg) significantly decreased escape latency between 2(nd) and 5(th) sessions, while zaprinast (10 mg/kg) significantly decreased escape latency only in 2(nd) session. Rolipram (0.05 and 0.1 mg/kg) and zaprinast (10 mg/kg) significantly increased time spent in escape platform's quadrant in probe trial of MWM test; only rolipram decreased mean distance to platform, while zaprinast had no effect on mean distance to platform. Zaprinast (3 and 10 mg/kg) significantly decreased number of errors compared to control group, while rolipram (0.05 and 0.1mg/kg) had no effect on number of errors in retention trial of RAM test. Rolipram (0.05 and 0.1 mg/kg) and zaprinast (10 mg/kg) significantly decreased time spent to complete retention trial (latency) compared to control group. Our study revealed that both zaprinast and rolipram enhanced spatial memory in MWM, while zaprinast seems to have more memory enhancing effects compared to rolipram in radial arm maze test.

  18. Erythropoietin Improves Place Learning in an 8-Arm Radial Maze in Fimbria-Fornix Transected Rats

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    Hana Malá

    2005-01-01

    Full Text Available Systemically administered human recombinant erythropoietin (EPO may have the potential to reduce the cognitive and behavioral symptoms of mechanical brain injury. In a series of studies, we address this possibility. We previously found that EPO given to fimbriafornix transected rats at the moment of injury could substantially improve the posttraumatic acquisition of an allocentric place learning task when such a task is administered in a water maze. Due to the clinical importance of such results, it is important to scrutinize whether the therapeutic effect of EPO is specific to the experimental setup of our original experiments or generalizes across test situations. Consequently, here we studied the effects of similarly administered EPO in fimbria-fornix transected and control operated rats, respectively, evaluating the posttraumatic behavioral/cognitive abilities in an allocentric place learning task administered in an 8-arm radial maze. The administration of EPO to the hippocampally injured rats was associated with a virtually complete elimination of the otherwise severe behavioral impairment caused by fimbria-fornix transection. In contrast, EPO had no detectable effect on the task acquisition of non-lesioned animals. The results of the present study confirm our previous demonstration of EPO's ability to reduce or eliminate the behavioral/cognitive consequences of mechanical injury to the hippocampus, while adding the important observation that such a therapeutic effect is not restricted to the specific experimental setup previously studied.

  19. The effects of apparatus design and test procedure on learning and memory performance of C57BL/6J mice on the Barnes maze.

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    O'Leary, Timothy P; Brown, Richard E

    2012-01-30

    The Barnes maze is a visuo-spatial learning and memory test originally designed for use with rats, and later adapted for use with mice. The Barnes maze design and test procedure vary across studies using mice, but the effects of variation in Barnes maze design and test procedure on learning and memory in mice have not yet been investigated. Therefore the present experiment investigates whether test procedures, such as the number of habituation trials and parameters of the probe trial (correct zone size and trial length) influence learning and memory performance on three Barnes maze designs that differed in size and the presence of a wall with intra-maze visual cues. Performance was compared across the three mazes to determine how apparatus design influences visuo-spatial cue use. The number of habituation trials and parameters of the probe trial had small effects on learning and memory performance. Apparatus design, had little effect on acquisition performance but had a significant effect on memory performance. Mice on a maze with a small diameter, external wall and intra-maze visual cues had very poor visuo-spatial memory relative to mice tested on small and large diameter mazes without a wall or intra-maze visual cues. Assessment of visuo-spatial cue use indicated that mice do not rely on visuo-spatial cues to locate the escape hole on the small-diameter maze with a wall and intra-maze visual cues, but show reliable visuo-spatial cue use on small or large diameter mazes with no wall. These results indicate that apparatus design influences search strategy use and memory performance on the Barnes maze, and that including a wall around the edge of the Barnes maze decreases visuo-spatial cue use.

  20. Learning about cognition risk with the radial-arm maze in the developmental neurotoxicology battery.

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    Levin, Edward D

    2015-01-01

    Cognitive dysfunction has been found in epidemiological studies to be among the most sensitive impairments associated with developmental exposure to a variety of environmental contaminants from heavy metals to polyhalogenated hydrocarbons and pesticides. These chemicals have been also shown to impair cognitive function after developmental exposure in experimental animal models. The radial-arm maze (RAM) has proven to be a sensitive and reliable way to assess both learning and memory in a variety of species, most often in rats and mice. The RAM is a very adaptable test method that takes advantage of rodents' instinct to explore new places in the environment to forage. That is, rodents do not need to be trained to run through the maze; they will normally do this from the initial session of testing. Training with differential reinforcement for arm choices provides a more rigorous test of learning and memory. The RAM is quite adaptable for assessing various aspects of cognition. Although the RAM has been mostly used to assess spatial learning and memory, it can be configured to assess non-spatial memory as well. Both working and reference memory can be easily distinguished. The RAM can be run with both appetitive (food reinforced) and aversive (water escape) motivators. The RAM has been found to be sensitive to a wide variety of developmental toxicants including heavy metals such as mercury and pesticides such as chlorpyrifos. There is an extremely rich literature especially with rats showing the effects of many types of brain lesions and drug effects so that the participation of a wide variety of neural systems in RAM performance is known. These systems, notably the hippocampus and frontal cortex, and acetylcholine and glutamate neurotransmitter systems, are the same neural systems that have been shown in humans to be critical for learning and memory. This considerably aids the interpretation of neurobehavioral toxicity studies.

  1. The effect of cul length and hippocampal lesions on maze learning in the rat.

    Science.gov (United States)

    Strong, P N

    1978-01-01

    Twenty-four rats, 8 with bilateral hippocampal lesions, 8 with cortical lesions and 8 unoperated rats, were tested on one of 2 mazes. Half of each group were run in a conventional 5 choice multiple Y maze. The other half were run in a symetrical, long cul maze in which distance and number of successive choice point were equal for a right or wrong choice before the animal reached an cul end or the goal box. The correct path in the long cul maze was identical to that of the short cul maze. S's were run one trial a day for 15 days. On the symetrical, long cul maze there were no differences between groups. On the short cul maze, hippocampals were significantly worse than control S's and looked similar to control S's on the long cul maze. The results are interpreted in terms of frustration theory.

  2. 5-HTT deficiency affects neuroplasticity and increases stress sensitivity resulting in altered spatial learning performance in the Morris water maze but not in the Barnes maze.

    Directory of Open Access Journals (Sweden)

    Margherita M Karabeg

    Full Text Available The purpose of this study was to evaluate whether spatial hippocampus-dependent learning is affected by the serotonergic system and stress. Therefore, 5-HTT knockout (-/-, heterozygous (+/- and wildtype (+/+ mice were subjected to the Barnes maze (BM and the Morris water maze (WM, the latter being discussed as more aversive. Additionally, immediate early gene (IEG expression, hippocampal adult neurogenesis (aN, and blood plasma corticosterone were analyzed. While the performance of 5-HTT-/- mice in the BM was undistinguishable from both other genotypes, they performed worse in the WM. However, in the course of the repeated WM trials 5-HTT-/- mice advanced to wildtype level. The experience of a single trial of either the WM or the BM resulted in increased plasma corticosterone levels in all genotypes. After several trials 5-HTT-/- mice exhibited higher corticosterone concentrations compared with both other genotypes in both tests. Corticosterone levels were highest in 5-HTT-/- mice tested in the WM indicating greater aversiveness of the WM and a greater stress sensitivity of 5-HTT deficient mice. Quantitative immunohistochemistry in the hippocampus revealed increased cell counts positive for the IEG products cFos and Arc as well as for proliferation marker Ki67 and immature neuron marker NeuroD in 5-HTT-/- mice compared to 5-HTT+/+ mice, irrespective of the test. Most differences were found in the suprapyramidal blade of the dentate gyrus of the septal hippocampus. Ki67-immunohistochemistry revealed a genotype x environment interaction with 5-HTT genotype differences in naïve controls and WM experience exclusively yielding more Ki67-positive cells in 5-HTT+/+ mice. Moreover, in 5-HTT-/- mice we demonstrate that learning performance correlates with the extent of aN. Overall, higher baseline IEG expression and increased an in the hippocampus of 5-HTT-/- mice together with increased stress sensitivity may constitute the neurobiological correlate of

  3. 5-HTT deficiency affects neuroplasticity and increases stress sensitivity resulting in altered spatial learning performance in the Morris water maze but not in the Barnes maze.

    Science.gov (United States)

    Karabeg, Margherita M; Grauthoff, Sandra; Kollert, Sina Y; Weidner, Magdalena; Heiming, Rebecca S; Jansen, Friederike; Popp, Sandy; Kaiser, Sylvia; Lesch, Klaus-Peter; Sachser, Norbert; Schmitt, Angelika G; Lewejohann, Lars

    2013-01-01

    The purpose of this study was to evaluate whether spatial hippocampus-dependent learning is affected by the serotonergic system and stress. Therefore, 5-HTT knockout (-/-), heterozygous (+/-) and wildtype (+/+) mice were subjected to the Barnes maze (BM) and the Morris water maze (WM), the latter being discussed as more aversive. Additionally, immediate early gene (IEG) expression, hippocampal adult neurogenesis (aN), and blood plasma corticosterone were analyzed. While the performance of 5-HTT-/- mice in the BM was undistinguishable from both other genotypes, they performed worse in the WM. However, in the course of the repeated WM trials 5-HTT-/- mice advanced to wildtype level. The experience of a single trial of either the WM or the BM resulted in increased plasma corticosterone levels in all genotypes. After several trials 5-HTT-/- mice exhibited higher corticosterone concentrations compared with both other genotypes in both tests. Corticosterone levels were highest in 5-HTT-/- mice tested in the WM indicating greater aversiveness of the WM and a greater stress sensitivity of 5-HTT deficient mice. Quantitative immunohistochemistry in the hippocampus revealed increased cell counts positive for the IEG products cFos and Arc as well as for proliferation marker Ki67 and immature neuron marker NeuroD in 5-HTT-/- mice compared to 5-HTT+/+ mice, irrespective of the test. Most differences were found in the suprapyramidal blade of the dentate gyrus of the septal hippocampus. Ki67-immunohistochemistry revealed a genotype x environment interaction with 5-HTT genotype differences in naïve controls and WM experience exclusively yielding more Ki67-positive cells in 5-HTT+/+ mice. Moreover, in 5-HTT-/- mice we demonstrate that learning performance correlates with the extent of aN. Overall, higher baseline IEG expression and increased an in the hippocampus of 5-HTT-/- mice together with increased stress sensitivity may constitute the neurobiological correlate of raised

  4. Decoding the view expectation during learned maze navigation from human fronto-parietal network.

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    Shikauchi, Yumi; Ishii, Shin

    2015-12-03

    Humans use external cues and prior knowledge about the environment to monitor their positions during spatial navigation. View expectation is essential for correlating scene views with a cognitive map. To determine how the brain performs view expectation during spatial navigation, we applied a multiple parallel decoding technique to functional magnetic resonance imaging (fMRI) when human participants performed scene choice tasks in learned maze navigation environments. We decoded participants' view expectation from fMRI signals in parietal and medial prefrontal cortices, whereas activity patterns in occipital cortex represented various types of external cues. The decoder's output reflected participants' expectations even when they were wrong, corresponding to subjective beliefs opposed to objective reality. Thus, view expectation is subjectively represented in human brain, and the fronto-parietal network is involved in integrating external cues and prior knowledge during spatial navigation.

  5. Habituation under stress: shocked mice show nonassociative learning in a T-maze.

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    Mitchell, D; Osborne, E W; O'Boyle, M W

    1985-03-01

    Conflicting predictions of reinforcement and neophobia-arousal theories were evaluated in a simple choice task. Four groups of C57BL/6J mice were administered daily two-trial tests in a uniform T-maze for 10 consecutive days. For three groups, the contingencies of footshock treatments were manipulated to reinforce alternation, perseveration, or both. A control group that was not administered footshock alternated, but all three groups that were stressed perseverated more and more across tests, despite the differences in reinforcement contingencies. These results are inconsistent with the predictions of reinforcement theory but consistent with the view that stressed or aroused animals are neophobic and use nonassociative learning (habituation) to distinguish between novel and familiar alternatives.

  6. DSTYK kinase domain ablation impaired the mice capabilities of learning and memory in water maze test.

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    Li, Kui; Liu, Ji-Wei; Zhu, Zhi-Chuan; Wang, Hong-Tao; Zu, Yong; Liu, Yong-Jie; Yang, Yan-Hong; Xiong, Zhi-Qi; Shen, Xu; Chen, Rui; Zheng, Jing; Hu, Ze-Lan

    2014-01-01

    DSTYK (Dual serine/threonine and tyrosine protein kinase) is a putative dual Ser/Thr and Tyr protein kinase with unique structural features. It is proposed that DSTYK may play important roles in brain because of its high expression in most brain areas. In the present study, a DSTYK knockout (KO) mouse line with the ablation of C-terminal of DSTYK including the kinase domain was generated to study the physiological function of DSTYK. The DSTYK KO mice are fertile and have no significant morphological defects revealed by Nissl staining compared with wildtype mice. Open field test and rotarod test showed there is no obvious difference in basic motor and balance capacity between the DSTYK homozygous KO mice and DSTYK heterozygous KO mice. In water maze test, however, the DSTYK homozygous KO mice show impaired capabilities of learning and memory compared with the DSTYK heterozygous KO mice.

  7. Learning Strategy Selection in the Water Maze and Hippocampal CREB Phosphorylation Differ in Two Inbred Strains of Mice

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    Sung, Jin-Young; Goo, June-Seo; Lee, Dong-Eun; Jin, Da-Qing; Bizon, Jennifer L.; Gallagher, Michela; Han, Jung-Soo

    2008-01-01

    Learning strategy selection was assessed in two different inbred strains of mice, C57BL/6 and DBA/2, which are used for developing genetically modified mouse models. Male mice received a training protocol in a water maze using alternating blocks of visible and hidden platform trials, during which mice escaped to a single location. After training,…

  8. 2-Methyl-6-(phenylethynyl pyridine (MPEP reverses maze learning and PSD-95 deficits in Fmr1 knock-out mice.

    Directory of Open Access Journals (Sweden)

    Réno Michelle Gandhi

    2014-03-01

    Full Text Available Fragile X syndrome (FXS is caused by the lack of expression of the fragile X mental retardation protein (FMRP, which results in intellectual disability and other debilitating symptoms including impairment of visual-spatial functioning. FXS is the only single-gene disorder that is highly co-morbid with autism spectrum disorder and can therefore provide insight into its pathophysiology. Lack of FMRP results in altered group I metabotropic glutamate receptor (mGluR signalling, which is a target for putative treatments. The Hebb-Williams (H-W mazes are a set of increasingly complex spatial navigation problems that depend on intact hippocampal and thus mGluR-5 functioning. In the present investigation, we examined whether an antagonist of mGluR-5 would reverse previously described behavioural deficits in Fmr1 KO mice. Mice were trained on a subset of the H-W mazes and then treated with either 20 mg/kg of an mGluR-5 antagonist, 2-Methyl-6-(phenylethynyl pyridine (MPEP; n = 11 or an equivalent dose of saline (n = 11 prior to running test mazes. Latency and errors were dependent variables recorded during the test phase. Immediately after completing each test, marble-burying behavior was assessed which confirmed that the drug treatment was pharmacologically active during maze learning. Although latency was not statistically different between the groups, MPEP treated Fmr1 KO mice made significantly fewer errors on mazes deemed more difficult suggesting a reversal of the behavioural deficit. MPEP treated mice were also less perseverative and impulsive when navigating mazes. Furthermore, MPEP treatment reversed PSD-95 protein deficits in Fmr1 KO treated mice, whereas levels of a control protein (β-tubulin remained unchanged. These data further validate MPEP as a potentially beneficial treatment for FXS. Our findings also suggest that adapted H-W mazes may be a useful tool to document alterations in behavioural functioning following pharmacological

  9. Egocentric virtual maze learning in adult survivors of childhood abuse with dissociative disorders: evidence from functional magnetic resonance imaging.

    Science.gov (United States)

    Weniger, Godehard; Siemerkus, Jakob; Barke, Antonia; Lange, Claudia; Ruhleder, Mirjana; Sachsse, Ulrich; Schmidt-Samoa, Carsten; Dechent, Peter; Irle, Eva

    2013-05-30

    Present neuroimaging findings suggest two subtypes of trauma response, one characterized predominantly by hyperarousal and intrusions, and the other primarily by dissociative symptoms. The neural underpinnings of these two subtypes need to be better defined. Fourteen women with childhood abuse and the current diagnosis of dissociative amnesia or dissociative identity disorder but without posttraumatic stress disorder (PTSD) and 14 matched healthy comparison subjects underwent functional magnetic resonance imaging (fMRI) while finding their way in a virtual maze. The virtual maze presented a first-person view (egocentric), lacked any topographical landmarks and could be learned only by using egocentric navigation strategies. Participants with dissociative disorders (DD) were not impaired in learning the virtual maze when compared with controls, and showed a similar, although weaker, pattern of activity changes during egocentric learning when compared with controls. Stronger dissociative disorder severity of participants with DD was related to better virtual maze performance, and to stronger activity increase within the cingulate gyrus and the precuneus. Our results add to the present knowledge of preserved attentional and visuospatial mnemonic functioning in individuals with DD.

  10. Rapid learning of magnetic compass direction by C57BL/6 mice in a 4-armed 'plus' water maze.

    Directory of Open Access Journals (Sweden)

    John B Phillips

    Full Text Available Magnetoreception has been demonstrated in all five vertebrate classes. In rodents, nest building experiments have shown the use of magnetic cues by two families of molerats, Siberian hamsters and C57BL/6 mice. However, assays widely used to study rodent spatial cognition (e.g. water maze, radial arm maze have failed to provide evidence for the use of magnetic cues. Here we show that C57BL/6 mice can learn the magnetic direction of a submerged platform in a 4-armed (plus water maze. Naïve mice were given two brief training trials. In each trial, a mouse was confined to one arm of the maze with the submerged platform at the outer end in a predetermined alignment relative to magnetic north. Between trials, the training arm and magnetic field were rotated by 180(° so that the mouse had to swim in the same magnetic direction to reach the submerged platform. The directional preference of each mouse was tested once in one of four magnetic field alignments by releasing it at the center of the maze with access to all four arms. Equal numbers of responses were obtained from mice tested in the four symmetrical magnetic field alignments. Findings show that two training trials are sufficient for mice to learn the magnetic direction of the submerged platform in a plus water maze. The success of these experiments may be explained by: (1 absence of alternative directional cues (2, rotation of magnetic field alignment, and (3 electromagnetic shielding to minimize radio frequency interference that has been shown to interfere with magnetic compass orientation of birds. These findings confirm that mice have a well-developed magnetic compass, and give further impetus to the question of whether epigeic rodents (e.g., mice and rats have a photoreceptor-based magnetic compass similar to that found in amphibians and migratory birds.

  11. The effect of Resveratrol flavonoid on learning and memory in passive avoidance and Y maze in diabetic rat

    Directory of Open Access Journals (Sweden)

    Sima Nasri

    2014-04-01

    Full Text Available Background: Diabetes type I is accompanied with disturbances in cognitive skills, memory and learning. In this research, we evaluated the effect of resveratrol chronic treatment on learning and memory in diabetic male rats. Material and Methods: Rats were divided into 4 groups: control, resveratrol-treated control, diabetic and resveratrol-treated diabetic groups. We used streptozotosin for inducing diabetes. Resveratrol (10mg/kg I.p. was administered for 8 weeks. For evaluation of learning and memory, passive avoidance test and Y-maze task were used. For Statistical analysis, SPSS software and paired T-test and one-way ANOVA were used. Results: Resveratrol decreased serum glucose in diabetic rats (P<0.01. In passive avoidance learning, there wasn’t any significant difference in initial latency between diabetic and treated- diabetic group. Also, a significant decrease of step latency was observed in diabetic and treated diabetic rats (P<0.01. In Y maze, Resveratrol improved alternation percentage in diabetic rats. Conclusion: Probably due to different mechanism of long term and short term memory, long term resveratrol treatment didn’t improve memory and learning in passive avoidance learning. In Y maze, method for determining the spatial memory, resveratrol improved spatial memory in diabetic rats. Resveratrol not only regulates glucose in diabetic rats but also it improves short term memory.

  12. Optimization of Apparatus Design and Behavioral Measures for the Assessment of Visuo-Spatial Learning and Memory of Mice on the Barnes Maze

    Science.gov (United States)

    O'Leary, Timothy P.; Brown, Richard E.

    2013-01-01

    We have previously shown that apparatus design can affect visual-spatial cue use and memory performance of mice on the Barnes maze. The present experiment extends these findings by determining the optimal behavioral measures and test procedure for analyzing visuo-spatial learning and memory in three different Barnes maze designs. Male and female…

  13. Optimization of apparatus design and behavioral measures for the assessment of visuo-spatial learning and memory of mice on the Barnes maze.

    Science.gov (United States)

    O'Leary, Timothy P; Brown, Richard E

    2013-01-15

    We have previously shown that apparatus design can affect visual-spatial cue use and memory performance of mice on the Barnes maze. The present experiment extends these findings by determining the optimal behavioral measures and test procedure for analyzing visuo-spatial learning and memory in three different Barnes maze designs. Male and female C57BL/6J mice were trained with a stable or random escape hole location and the sensitivities (statistical power) of four commonly used measures of learning and three measures of memory to detect differences between these training procedures were compared on each maze design. A maze design with a large diameter and no wall was optimal, because mice showed a reliable use of extra-maze visual cues, visuo-spatial search strategies, and spatial memory. A maze design with a small diameter, surrounding wall, and intra-maze visual cues was the least sensitive for determining visuo-spatial learning and memory, because mice showed little evidence of extra-maze cue use. Errors, distance traveled, and hole deviation scores were more sensitive measures of learning than latency to find the escape hole. Measures based on locating the escape hole (primary measures) were more sensitive than measures based on entering the escape hole (total measures). Measures of memory had similar levels of sensitivity on each maze. This experiment demonstrates that both apparatus design and the behavioral measures used as indicators of learning and memory can influence the ability of the Barnes maze to detect visuo-spatial learning and memory impairments in mice.

  14. 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.

  15. Long-term enhancement of maze learning in mice via a generalized Mozart effect.

    Science.gov (United States)

    Aoun, Peter; Jones, Timothy; Shaw, Gordon L; Bodner, Mark

    2005-12-01

    An animal model of the 'generalized Mozart effect' (GME) - enhanced/normalized higher brain function in response to music exposure - has been established. We extend those results in two studies using another species (mice). Study 1: (1) maze testing after music exposure was extended to a minimum of 6 hours; (2) no exposure to music in utero. Study 2: (1) music exposure time further reduced; (2) maze testing extended to 24 hours. Study 1: two mouse groups were exposed to music continuously for 10 hours per day for 10 weeks (Group I: Mozart's Sonata K.448, Group II: Beethoven's Fur Elise). After 10 weeks, the ability to negotiate a T-maze was assessed (recording working time in maze, number of errors). Maze ability was tested 6 hours following the last music exposure. Study 2: two mouse groups were exposed periodically to music (58% silence) 10 hours per day for 10 weeks. Experiments after 10 weeks examined the groups' abilities to run the maze (recording working time/errors). Experiments were conducted 24 hours following the last music exposure. The Mozart group exhibited significant enhancements compared with the control mice in both studies, i.e. significantly lower working time (p<0.05) and committed fewer errors. Observation of GME in another species supports its generality for the mammalian cortex. The absence of a GME in fMRI studies for the control music also indicates a neurophysiological basis. With extended exposure, GME is a long-term effect, indicating potential clinical importance. It has been demonstrated that GME reduces neuropathological spiking significantly in epileptics. We discuss the relevance of this study for epilepsy treatment.

  16. Effects of spaced learning in the water maze on development of dentate granule cells generated in adult mice.

    Science.gov (United States)

    Trinchero, Mariela F; Koehl, Muriel; Bechakra, Malik; Delage, Pauline; Charrier, Vanessa; Grosjean, Noelle; Ladeveze, Elodie; Schinder, Alejandro F; Abrous, D Nora

    2015-11-01

    New dentate granule cells (GCs) are generated in the hippocampus throughout life. These adult-born neurons are required for spatial learning in the Morris water maze (MWM). In rats, spatial learning shapes the network by regulating their number and dendritic development. Here, we explored whether such modulatory effects exist in mice. New GCs were tagged using thymidine analogs or a GFP-expressing retrovirus. Animals were exposed to a reference memory protocol for 10-14 days (spaced training) at different times after newborn cells labeling. Cell proliferation, cell survival, cell death, neuronal phenotype, and dendritic and spine development were examined using immunohistochemistry. Surprisingly, spatial learning did not modify any of the parameters under scrutiny including cell number and dendritic morphology. These results suggest that although new GCs are required in mice for spatial learning in the MWM, they are, at least for the developmental intervals analyzed here, refractory to behavioral stimuli generated in the course of learning in the MWM.

  17. Differential involvement of hippocampal calcineurin during learning and reversal learning in a Y-maze task

    NARCIS (Netherlands)

    Havekes, Robbert; Nijholt, Ingrid M.; Luiten, Paul G. M.; Van der Zee, Eddy A.

    2006-01-01

    The regulation and function of the calcium-dependent phosphatase calcineurin (CaN, protein phosphatase 2B) in learning and memory remain unclear, although recent work indicates that CaN may play a differential role in training and reversal training. To gain more insight into the involvement of CaN

  18. Differential involvement of hippocampal calcineurin during learning and reversal learning in a Y-maze task

    NARCIS (Netherlands)

    Havekes, Robbert; Nijholt, Ingrid M.; Luiten, Paul G. M.; Van der Zee, Eddy A.

    2006-01-01

    The regulation and function of the calcium-dependent phosphatase calcineurin (CaN, protein phosphatase 2B) in learning and memory remain unclear, although recent work indicates that CaN may play a differential role in training and reversal training. To gain more insight into the involvement of CaN i

  19. Search strategy selection in the Morris water maze indicates allocentric map formation during learning that underpins spatial memory formation.

    Science.gov (United States)

    Rogers, Jake; Churilov, Leonid; Hannan, Anthony J; Renoir, Thibault

    2017-03-01

    Using a Matlab classification algorithm, we demonstrate that a highly salient distal cue array is required for significantly increased likelihoods of spatial search strategy selection during Morris water maze spatial learning. We hypothesized that increased spatial search strategy selection during spatial learning would be the key measure demonstrating the formation of an allocentric map to the escape location. Spatial memory, as indicated by quadrant preference for the area of the pool formally containing the hidden platform, was assessed as the main measure that this allocentric map had formed during spatial learning. Our C57BL/6J wild-type (WT) mice exhibit quadrant preference in the highly salient cue paradigm but not the low, corresponding with a 120% increase in the odds of a spatial search strategy selection during learning. In contrast, quadrant preference remains absent in serotonin 1A receptor (5-HT1AR) knockout (KO) mice, who exhibit impaired search strategy selection during spatial learning. Additionally, we also aimed to assess the impact of the quality of the distal cue array on the spatial learning curves of both latency to platform and path length using mixed-effect regression models and found no significant associations or interactions. In contrast, we demonstrated that the spatial learning curve for search strategy selection was absent during training in the low saliency paradigm. Therefore, we propose that allocentric search strategy selection during spatial learning is the learning parameter in mice that robustly indicates the formation of a cognitive map for the escape goal location. These results also suggest that both latency to platform and path length spatial learning curves do not discriminate between allocentric and egocentric spatial learning and do not reliably predict spatial memory formation. We also show that spatial memory, as indicated by the absolute time in the quadrant formerly containing the hidden platform alone (without

  20. Validation and scopolamine-reversal of latent learning in the water maze utilizing a revised direct platform placement procedure.

    Science.gov (United States)

    Malin, David H; Schaar, Krystal L; Izygon, Jonathan J; Nghiem, Duyen M; Jabitta, Sikirat Y; Henceroth, Mallori M; Chang, Yu-Hsuan; Daggett, Jenny M; Ward, Christopher P

    2015-08-01

    The Morris water maze is routinely used to explore neurobiological mechanisms of working memory. Humans can often acquire working memory relevant to performing a task by mere sensory observation, without having to actually perform the task followed by reinforcement. This can be modeled in the water maze through direct placement of a rat on the escape platform so that it can observe the location, and then assessing the subject's performance in swimming back to the platform. However, direct placement procedures have hardly been studied for two decades, reflecting a controversy about whether direct placement resulted in sufficiently rapid and direct swims back to the platform. In the present study, utilizing revised training methods, a more comprehensive measure of trajectory directness, a more rigorous sham-trained control procedure and an optimal placement-test interval, rats swam almost directly back to the platform in under 4s, significantly more quickly and directly than sham-trained subjects. Muscarinic cholinergic mechanisms, which are inactivated by scopolamine, are essential to memory for standard learning paradigms in the water maze. This experiment determined whether this would also be true for latent learning. ANOVA revealed significant negative effects of scopolamine on both speed and accuracy of trajectory, as well as significant positive effects of direct placement training vs. sham-training. In a probe trial, placement-trained animals without scopolamine spent significantly more time and path length in the target quadrant than trained rats with scopolamine and sham-trained rats without scopolamine. Scopolamine impairments are likely due to effects on memory, since the same dose had little effect on performance with a visible platform. The revised direct placement model offers a means of further comparing the neural mechanisms of latent learning with those of standard instrumental learning.

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

    Science.gov (United States)

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

    2010-01-01

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

  2. Supramammillary serotonin reduction alters place learning and concomitant hippocampal, septal, and supramammillar theta activity in a Morris water maze

    Science.gov (United States)

    Hernández-Pérez, J. Jesús; Gutiérrez-Guzmán, Blanca E.; López-Vázquez, Miguel Á.; Olvera-Cortés, María E.

    2015-01-01

    Hippocampal theta activity is related to spatial information processing, and high-frequency theta activity, in particular, has been linked to efficient spatial memory performance. Theta activity is regulated by the synchronizing ascending system (SAS), which includes mesencephalic and diencephalic relays. The supramamillary nucleus (SUMn) is located between the reticularis pontis oralis and the medial septum (MS), in close relation with the posterior hypothalamic nucleus (PHn), all of which are part of this ascending system. It has been proposed that the SUMn plays a role in the modulation of hippocampal theta-frequency; this could occur through direct connections between the SUMn and the hippocampus or through the influence of the SUMn on the MS. Serotonergic raphe neurons prominently innervate the hippocampus and several components of the SAS, including the SUMn. Serotonin desynchronizes hippocampal theta activity, and it has been proposed that serotonin may regulate learning through the modulation of hippocampal synchrony. In agreement with this hypothesis, serotonin depletion in the SUMn/PHn results in deficient spatial learning and alterations in CA1 theta activity-related learning in a Morris water maze. Because it has been reported that SUMn inactivation with lidocaine impairs the consolidation of reference memory, we asked whether changes in hippocampal theta activity related to learning would occur through serotonin depletion in the SUMn, together with deficiencies in memory. We infused 5,7-DHT bilaterally into the SUMn in rats and evaluated place learning in the standard Morris water maze task. Hippocampal (CA1 and dentate gyrus), septal and SUMn EEG were recorded during training of the test. The EEG power in each region and the coherence between the different regions were evaluated. Serotonin depletion in the SUMn induced deficient spatial learning and altered the expression of hippocampal high-frequency theta activity. These results provide evidence in

  3. Accelerated senescence prone mouse-8 shows early onset of deficits in spatial learning and memory in the radial six-arm water maze.

    Science.gov (United States)

    Chen, Gui-Hai; Wang, Yue-Ju; Wang, Xiao-Min; Zhou, Jiang-Ning

    2004-10-15

    Available data indicate that the senescence-accelerated prone mouse 8 (SAMP8) is an appropriate model of brain aging, with impairments in nonspatial learning and memory beginning as early as 2 months of age, and spatial learning and memory deficiencies not becoming apparent until after 4 months of age. However, with other strains (e.g., C57BL mice), the impairment in spatial memory was found earlier than that in nonspatial memory. We considered the possibility that the observed differences could be due to strain-specific differences in the training equipment. In the present study, a new optimized testing apparatus-the radial six-arm water maze (RAWM)-for detecting spatial learning and memory in mice, was employed, to determine whether there is impairment of spatial learning and memory in young SAMP8. The relationship between the spatial learning measures observed with the RAWM and the Morris maze, a classic spatial learning and memory testing apparatus, was also explored. It was found that, in the RAWM, rather than in the Morris maze, the impairment in spatial learning could be measured in SAMP8 mice as early as 3 months old, and the impairment in spatial memory in SAMP8 mice aged 5 months. These results suggested that the spatial learning and memory deficiencies could be found in early life of SAMP8 mice, and that RAWM and Morris maze each detect different aspects of spatial learning and memory.

  4. Un cas particulier du scénario dans l'apprentissage des langues : le labyrinthe (action maze Action Mazes: a special case of the scenario for language learning

    Directory of Open Access Journals (Sweden)

    Joseph Rézeau

    2008-03-01

    Full Text Available En didactique des langues l'approche actionnelle et les scénarios sont d'actualité, en lien avec les Tice (Technologies de l'Information et de la Communication pour l'Enseignement. Cependant, des activités de type labyrinthe (action mazes, courantes dans les années 1980 et souvent portées sur les micro-ordinateurs de l'époque, semblent quelque peu tombées dans l'oubli. Cet article entend montrer qu'il est relativement aisé de concevoir et de réaliser de telles activités sur une plateforme d'enseignement à distance telle que Moodle. Nous analyserons également l'impact d'une activité de type labyrinthe sur une population d'étudiants dans le cadre d'un enseignement d'anglais de type Lansad (langues pour spécialistes d'autres disciplines.The development of ICT in language teaching concurs with an interest in task-based approaches and scenarios. Surprisingly, however, such activities as "adventure games" and "action mazes" which were quite popular in CALL (Computer Assisted Language Learning in the 1980s seem to have fallen into oblivion. This article aims at demonstrating that it is relatively easy to design and implement "action mazes" on an LMS (Learning Management System such as Moodle. We shall then analyse the impact of an "action maze" learning activity on a population of students of ESP (English for Specific Purposes.

  5. Spatial and Reversal Learning in the Morris Water Maze Are Largely Resistant to Six Hours of REM Sleep Deprivation Following Training

    Science.gov (United States)

    Walsh, Christine M.; Booth, Victoria; Poe, Gina R.

    2011-01-01

    This first test of the role of REM (rapid eye movement) sleep in reversal spatial learning is also the first attempt to replicate a much cited pair of papers reporting that REM sleep deprivation impairs the consolidation of initial spatial learning in the Morris water maze. We hypothesized that REM sleep deprivation following training would impair…

  6. Spatial and Reversal Learning in the Morris Water Maze Are Largely Resistant to Six Hours of REM Sleep Deprivation Following Training

    Science.gov (United States)

    Walsh, Christine M.; Booth, Victoria; Poe, Gina R.

    2011-01-01

    This first test of the role of REM (rapid eye movement) sleep in reversal spatial learning is also the first attempt to replicate a much cited pair of papers reporting that REM sleep deprivation impairs the consolidation of initial spatial learning in the Morris water maze. We hypothesized that REM sleep deprivation following training would impair…

  7. Investigations on training, recall and reversal learning of a Y-maze by dwarf goats (Capra hircus): the impact of lateralisation.

    Science.gov (United States)

    Langbein, J

    2012-03-01

    We investigated maze learning in dwarf goats (Capra hircus) and the impact of lateralisation on learning. Lateralisation refers to the collection of phenomena in which external stimuli are perceived and processed differentially on the two sides of the brain and/or certain behaviours are preferentially performed by one side of the body. We trained 29 dwarf goats in a Y-maze, directing them to the opposite alley from that chosen in a free pre-run. In total, 13 goats were trained to the left alley (L-goats) and 16 goats to the right alley (R-goats). Recall of the trained alley was tested three months later. We then analysed reversal learning across 10 reversals. During training, the direction of the alley had an impact on learning. The number of runs required to reach the learning criterion was significantly lower in the L- than the R-goats. The goats recalled the trained alley three months later, with no difference between the L- and the R-goats. During the reversal learning, the reversal only tended to impact learning performance, whereas the directions of the new and the initially trained alley did not. Goats did not adopt a general rule with which to master the maze (e.g., win-stay/lose-shift) across the 10 reversals. Our results indicate a right hemisphere bias in the processing of visuospatial cues in the maze during initial training; however, no such impact was detected during reversal learning.

  8. Modafinil and memory: effects of modafinil on Morris water maze learning and Pavlovian fear conditioning.

    Science.gov (United States)

    Shuman, Tristan; Wood, Suzanne C; Anagnostaras, Stephan G

    2009-04-01

    Modafinil has been shown to promote wakefulness and some studies suggest the drug can improve cognitive function. Because of many similarities, the mechanism of action may be comparable to classical psychostimulants, although the exact mechanisms of modafinil's actions in wakefulness and cognitive enhancement are unknown. The current study aims to further examine the effects of modafinil as a cognitive enhancer on hippocampus-dependent memory in mice. A high dose of modafinil (75 mg/kg ip) given before training improved acquisition on a Morris water maze. When given only before testing, modafinil did not affect water maze performance. We also examined modafinil (0.075 to 75 mg/kg) on Pavlovian fear conditioning. A low dose of pretraining modafinil (0.75 mg/kg) enhanced memory of contextual fear conditioning (tested off-drug 1 week later) whereas a high dose (75 mg/kg) disrupted memory. Pretraining modafinil did not affect cued conditioning at any dose tested, and immediate posttraining modafinil had no effect on either cued or contextual fear. These results suggest that modafinil's effects of memory are more selective than amphetamine or cocaine and specific to hippocampus-dependent memory.

  9. Feedback control strategies for spatial navigation revealed by dynamic modelling of learning in the Morris water maze.

    Science.gov (United States)

    Fey, Dirk; Commins, Sean; Bullinger, Eric

    2011-04-01

    The Morris water maze is an experimental procedure in which animals learn to escape swimming in a pool using environmental cues. Despite its success in neuroscience and psychology for studying spatial learning and memory, the exact mnemonic and navigational demands of the task are not well understood. Here, we provide a mathematical model of rat swimming dynamics on a behavioural level. The model consists of a random walk, a heading change and a feedback control component in which learning is reflected in parameter changes of the feedback mechanism. The simplicity of the model renders it accessible and useful for analysis of experiments in which swimming paths are recorded. Here, we used the model to analyse an experiment in which rats were trained to find the platform with either three or one extramaze cue. Results indicate that the 3-cues group employs stronger feedback relying only on the actual visual input, whereas the 1-cue group employs weaker feedback relying to some extent on memory. Because the model parameters are linked to neurological processes, identifying different parameter values suggests the activation of different neuronal pathways.

  10. ApoE isoform modulates effects of cranial ⁵⁶Fe irradiation on spatial learning and memory in the water maze.

    Science.gov (United States)

    Yeiser, Lauren A; Villasana, Laura E; Raber, Jacob

    2013-01-15

    Apolipoprotein E, which plays an important role in lipid transport and metabolism and neuronal repair, might modulate the CNS risk following (56)Fe irradiation exposure during space missions. In this study, we investigated this risk by behavioral and cognitive testing male E2, E3, and E4 mice 3 months following cranial (56)Fe irradiation. In the open field, mice irradiated with 2 Gy showed higher activity levels than sham-irradiated mice or mice irradiated with 1 Gy. In addition, E2 mice showed higher activity and lower measures of anxiety than E3 and E4 mice in the open field and elevated zero maze. During hidden platform training, sham-irradiated mice showed most robust learning, 1 Gy irradiated mice reduced learning, and 2 Gy irradiated mice no improvement over the four sessions. In the water maze probe trials, sham-irradiated E2, E3, and E4 mice and E2 and E4 mice irradiated with 1 Gy showed spatial memory retention, but E3 mice irradiated with 1 Gy, and E2, E3, and E4 mice irradiated with 2 Gy did not. Thus, cranial (56)Fe irradiation increases activity levels in the open field and impairs spatial learning and memory in the water maze. E3 mice are more susceptible than E2 or E4 mice to impairments in spatial memory retention in the water maze, indicating that apoE isoform modulates the CNS risk following space missions.

  11. Spatial and Nonspatial Escape Strategies in the Barnes Maze

    Science.gov (United States)

    Harrison, Fiona E.; Reiserer, Randall S.; Tomarken, Andrew J.; McDonald, Michael P.

    2006-01-01

    The Barnes maze is a spatial memory task that requires subjects to learn the position of a hole that can be used to escape the brightly lit, open surface of the maze. Two experiments assessed the relative importance of spatial (extra-maze) versus proximal visible cues in solving the maze. In Experiment 1, four groups of mice were trained either…

  12. Erythropoietin improves place learning in an 8-arm radial maze in fimbria-fornix transected rats

    DEFF Research Database (Denmark)

    Malá, Hana; Alsina, Carina Gili; Madsen, Kathrine Skak;

    2005-01-01

    erythropoietin, EOP, fimbria-fornix, hippocampus, place learning, hjerneskade, funktionel genopretning, posttraumatisk rehabilitering, plasticitet, neuroprotektion, neurotrofiske effekter, 8-arms labyrint, rotte, indlæring, problemløsning...

  13. Intermittent swim stress causes Morris water maze performance deficits in a massed-learning trial procedure that are exacerbated by reboxetine.

    Science.gov (United States)

    Warner, Timothy A; Stafford, Nathaniel P; Rompala, Gregory R; Van Hoogenstyn, Andrew J; Elgert, Emily; Drugan, Robert C

    2013-11-15

    Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for research in this area, as many unanswered questions remain. Therefore, we sought to employ a novel animal model of depression known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already shown subsequent immobility in the forced swim test (FST), deficits in instrumental and spatial (spaced-trial procedure), and responsiveness to norepinephrine. We are now examining how this will translate in the Morris water maze for rats in a massed-learning trial procedure, and further assessing ISS sensitivity toward norepinephrine selective anti-depressant drugs. The results indicated no difference in cued learning when the platform was visible in the water maze, but a hidden platform task revealed poorer spatial learning for ISS-exposed rats versus controls. In terms of spatial memory, there was a notable ISS-induced deficit 1h after the learning trials, regardless of performance on the previous platform task. Interestingly, the administration of reboxetine interfered with the spatial learning and memory trials for both ISS and CC groups. As a result, ISS exposure compromised spatial learning and memory in the Morris water maze, and norepinephrine does not appear to be a mediator of this deficit. The results demonstrate a key difference in the effects of reboxetine in a massed- vs. spaced-learning trial procedure in the Morris water maze following ISS exposure.

  14. Synergistic effects of dopamine D2-like receptor antagonist sulpiride and β-blocker propranolol on learning in the carousel maze, a dry-land spatial navigation task.

    Science.gov (United States)

    Prokopova, Iva; Bahnik, Stepan; Doulames, Vanessa; Vales, Karel; Petrasek, Tomas; Svoboda, Jan; Stuchlik, Ales

    2012-07-01

    Spatial navigation attracts the attention of neuroscientists as an animal analogue of human declarative memory. The Carousel maze is a dry-land navigational paradigm, which proved to be useful in studying neurobiological substrates of learning. The task involves avoidance of a stable sector on a rotating arena and is highly dependent upon the hippocampus. The present study aims at testing hypothesis that sulpiride (a centrally-active dopamine D2-like receptor antagonist) and propranolol (a beta-blocker) impair spatial learning in the Carousel maze after combined systemic administration. These doses were previously shown to be subthreshold in this task. Results showed that both substances affected behavior and significantly potentiated their negative effects on spatial learning. This suggests central interaction of both types of receptors in influencing acquisition of this dynamic-environment task.

  15. Mouse genetic differences in voluntary wheel running, adult hippocampal neurogenesis and learning on the multi-strain-adapted plus water maze.

    Science.gov (United States)

    Merritt, Jennifer R; Rhodes, Justin S

    2015-03-01

    Moderate levels of aerobic exercise broadly enhance cognition throughout the lifespan. One hypothesized contributing mechanism is increased adult hippocampal neurogenesis. Recently, we measured the effects of voluntary wheel running on adult hippocampal neurogenesis in 12 different mouse strains, and found increased neurogenesis in all strains, ranging from 2- to 5-fold depending on the strain. The purpose of this study was to determine the extent to which increased neurogenesis from wheel running is associated with enhanced performance on the water maze for 5 of the 12 strains, chosen based on their levels of neurogenesis observed in the previous study (C57BL/6 J, 129S1/SvImJ, B6129SF1/J, DBA/2 J, and B6D2F1/J). Mice were housed with or without a running wheels for 30 days then tested for learning and memory on the plus water maze, adapted for multiple strains, and rotarod test of motor performance. The first 10 days, animals were injected with BrdU to label dividing cells. After behavioral testing animals were euthanized to measure adult hippocampal neurogenesis using standard methods. Levels of neurogenesis depended on strain but all mice had a similar increase in neurogenesis in response to exercise. All mice acquired the water maze but performance depended on strain. Exercise improved water maze performance in all strains to a similar degree. Rotarod performance depended on strain. Exercise improved rotarod performance only in DBA/2 J and B6D2F1/J mice. Taken together, results demonstrate that despite different levels of neurogenesis, memory performance and motor coordination in these mouse strains, all strains have the capacity to increase neurogenesis and improve learning on the water maze through voluntary wheel running.

  16. Prenatal exposure to alcohol does not affect radial maze learning and hippocampal mossy fiber sizes in three inbred strains of mouse

    Directory of Open Access Journals (Sweden)

    Bertholet Jean-Yves

    2005-04-01

    Full Text Available Abstract Background The aim of this study was to investigate the effects of prenatal alcohol exposure on radial-maze learning and hippocampal neuroanatomy, particularly the sizes of the intra- and infrapyramidal mossy fiber (IIPMF terminal fields, in three inbred strains of mice (C57BL/6J, BALB/cJ, and DBA/2J. Results Although we anticipated a modification of both learning and IIPMF sizes, no such effects were detected. Prenatal alcohol exposure did, however, interfere with reproduction in C57BL/6J animals and decrease body and brain weight (in interaction with the genotype at adult age. Conclusion Prenatal alcohol exposure influenced neither radial maze performance nor the sizes of the IIPMF terminal fields. We believe that future research should be pointed either at different targets when using mouse models for Fetal Alcohol Syndrome (e.g. more complicated behavioral paradigms, different hippocampal substructures, or other brain structures or involve different animal models.

  17. Partial reinforcement effects on learning and extinction of place preferences in the water maze.

    Science.gov (United States)

    Prados, José; Sansa, Joan; Artigas, Antonio A

    2008-11-01

    In two experiments, two groups of rats were trained in a navigation task according to either a continuous or a partial schedule of reinforcement. In Experiment 1, animals that were given continuous reinforcement extinguished the spatial response of approaching the goal location more readily than animals given partial reinforcement-a partial reinforcement extinction effect. In Experiment 2, after partially or continuously reinforced training, animals were trained in a new task that made use of the same reinforcer according to a continuous reinforcement schedule. Animals initially given partial reinforcement performed better in the novel task than did rats initially given continuous reinforcement. These results replicate, in the spatial domain, well-known partial reinforcement phenomena typically observed in the context of Pavlovian and instrumental conditioning, suggesting that similar principles govern spatial and associative learning. The results reported support the notion that salience modulation processes play a key role in determining partial reinforcement effects.

  18. Non-spatial pre-training in the water maze as a clinically relevant model for evaluating learning and memory in experimental TBI.

    Science.gov (United States)

    Wagner, Amy K; Brayer, Samuel W; Hurwitz, Max; Niyonkuru, Christian; Zou, Huichao; Failla, Michelle; Arenth, Patricia; Manole, Mioara D; Skidmore, Elizabeth; Thiels, Edda

    2013-11-01

    Explicit and implicit learning and memory networks exist where each network can facilitate or inhibit cognition. Clinical evidence suggests that implicit networks are relatively preserved after traumatic brain injury (TBI). Non-spatial pre-training (NSPT) in the Morris Water Maze (MWM) provides the necessary behavioral components to complete the task, while limiting the formation of spatial maps. Our study utilized NSPT in the MWM to assess implicit and explicit learning and memory system deficits in the controlled cortical impact (CCI) model of TBI. 76 adult male Sprague-Dawley rats were divided: CCI vs. sham surgery, NSPT vs. No-NSPT, and cued vs. non-cued groups. NSPT occurred for 4d prior to surgery (dynamic hidden platform location, extra-maze cues covered, static pool entry point). Acquisition (d14-18), Probe/Visible Platform (d19), and Reversal (d20-21) trials were conducted with or without extra-maze cues. Novel time allocation and search strategy selection metrics were utilized. Results indicated implicit and explicit learning/memory networks are distinguishable in the MWM. In the cued condition, NSPT reduced thigmotaxis, improved place learning, and largely eliminated the apparent injury-induced deficits typically observed between untrained CCI and sham rats. However, among NSPT groups, incorporation of cues into search strategy selection for CCI rats was relatively impaired compared to shams. Non-cued condition performance showed sham/NSPT and CCI/NSPT rats perform similarly, suggesting implicit memory networks are largely intact 2weeks after CCI. Place learning differences between CCI/NSPT and sham/NSPT rats more accurately reflect spatial deficits in our CCI model compared to untrained controls. These data suggest NSPT as a clinically relevant construct for evaluating potential neurorestorative and neuroprotective therapies. These findings also support development of non-spatial cognitive training paradigms for evaluating rehabilitation relevant

  19. Lesions of the dorsomedial striatum delay spatial learning and render cue-based navigation inflexible in a water maze task in mice.

    Science.gov (United States)

    Lee, Anni S; André, Jessica M; Pittenger, Christopher

    2014-01-01

    The dorsal striatum is involved in cue-based navigation strategies and in the development of habits. It has been proposed that striatum-dependent cued navigation competes with hippocampus-dependent spatial navigation in some circumstances. We have previously shown that large lesions of the dorsal striatum, as well as impairment of corticostriatal synaptic plasticity in transgenic mice, can enhance spatial learning in a water maze task, presumably by the disruption of competitive interference. However, the dorsal striatum is not a homogeneous structure; both anatomical considerations and experimental studies in various paradigms show that dorsomedial and dorsolateral striatum are functionally distinct, although there is no precise anatomical or neurochemical boundary between them. Here we investigated the effect of restricted excitotoxic lesions of dorsomedial striatum (DMS) on cued and spatial water maze learning. We find that dorsomedial striatal lesions delay spatial learning but permit cued learning. After cued learning, lesioned animals showed inflexible search, resulting in repeated visits to the escape platform-associated cue. These results support a role for the DMS in behavioral flexibility rather than in cue-based navigation.

  20. Rats' Orientation at the Start Point Is Important for Spatial Learning in a Water T-Maze

    Science.gov (United States)

    Peckford, Genieve; McRae, Samantha M.; Thorpe, Christina M.; Martin, Gerard M.; Skinner, Darlene M.

    2013-01-01

    When trained to locate a hidden platform in a T-maze moved between two positions, rats appear to adopt a conditional strategy based on start point discrimination. To determine if location cues or orientation cues at the start point underlie this discrimination, separate groups of rats were trained on two place problems, each with unique start…

  1. Lego Mindstorm Maze Runner

    OpenAIRE

    Drakonakis, Konstantinos; Mentzelopoulos, Panagiotis

    2014-01-01

    This project describes a method for solving mazes using a path finding algorithm, specifically DFS. Its input consists of the NXT lego robot along with a color sensor and a colored ball, the constructed maze and a text (.txt) file that describes the structure of the maze. Subsequently, the output of our program in order of execution is the identification of the provided colored ball, the calculation of the maze's solution (path) and the actual movement of the robot through the maze carrying t...

  2. Lego Mindstorm Maze Runner

    OpenAIRE

    Drakonakis, Konstantinos; Mentzelopoulos, Panagiotis

    2014-01-01

    This project describes a method for solving mazes using a path finding algorithm, specifically DFS. Its input consists of the NXT lego robot along with a color sensor and a colored ball, the constructed maze and a text (.txt) file that describes the structure of the maze. Subsequently, the output of our program in order of execution is the identification of the provided colored ball, the calculation of the maze's solution (path) and the actual movement of the robot through the maze carrying t...

  3. Enhanced adolescent learning and hippocampal axonal projections following preadolescent spatial exposure to a water or dry maze.

    Science.gov (United States)

    Wartman, Brianne C; Gervais, Nicole J; Smith, Catherine; Comba, Rachel; Mumby, Dave G; Holahan, Matthew R

    2012-09-26

    The present work sought to determine whether preadolescent exposure to a different task in the same spatial environment would lead to enhancement of water-maze performance and changes in hippocampal connectivity. Separate groups of preadolescent (p16-p26) Long Evans rats (LER) were exposed to the same room and arena using either a water-maze (WM) or a dry-maze (DM), while a third group received no exposure to the spatial cues (NT) but were handled. Three weeks later, rats were tested on the WM or DM task in the same room where preadolescent exposure took place. This set up conditions where the DM/WM and WM/DM groups were exposed to the same spatial cues during the preadolescent and adolescent (p40-p44) phases but performed different tests allowing for the dissociation of spatial cue exposure and task familiarity on adolescent performance. When animals experienced similar preadolescent and adolescent conditions (WM/WM or DM/DM), there was improved performance over animals with no preadolescent spatial exposure (NT/WM or NT/DM). In group DM/WM, there was enhanced adolescent performance compared to group NT/WM. In contrast, group WM/DM did not show enhanced adolescent performance. Compared to groups with no preadolescent spatial exposure, groups with both preadolescent and adolescent spatial exposure showed elevated synaptophysin staining in the hippocampal CA3 region indicating an expanded axonal projection in this region. These data suggest the possibility that exposure to spatial cues during the preadolescent period, independent from task-specific requirements, contributes to enhanced adolescent spatial performance on the WM. This appears to be linked with the reorganization of axonal inputs to the CA3 region.

  4. Electric Current Solves Mazes

    Science.gov (United States)

    Ayrinhac, Simon

    2014-01-01

    We present in this work a demonstration of the maze-solving problem with electricity. Electric current flowing in a maze as a printed circuit produces Joule heating and the right way is instantaneously revealed with infrared thermal imaging. The basic properties of electric current can be discussed in this context, with this challenging question:…

  5. Rook Jumping Maze Design Considerations

    Science.gov (United States)

    Neller, Todd W.; Fisher, Adrian; Choga, Munyaradzi T.; Lalvani, Samir M.; McCarty, Kyle D.

    We define the Rook Jumping Maze, provide historical perspective, and describe a generation method for such mazes. When applying stochastic local search algorithms to maze design, most creative effort concerns the definition of an objective function that rates maze quality. We define and discuss several maze features to consider in such a function definition. Finally, we share our preferred design choices, make design process observations, and note the applicability of these techniques to variations of the Rook Jumping Maze.

  6. Learning strategy preference of 5XFAD transgenic mice depends on the sequence of place/spatial and cued training in the water maze task.

    Science.gov (United States)

    Cho, Woo-Hyun; Park, Jung-Cheol; Chung, ChiHye; Jeon, Won Kyung; Han, Jung-Soo

    2014-10-15

    Learning strategy preference was assessed in 5XFAD mice, which carry 5 familial Alzheimer's disease (AD) mutations. Mice were sequentially trained in cued and place/spatial versions of the water maze task. After training, a strategy preference test was conducted in which mice were required to choose between the spatial location where the platform had previously been during the place/spatial training, and a visible platform in a new location. 5XFAD and non-transgenic control mice showed equivalent escape performance in both training tasks. However, in the strategy preference test, 5XFAD mice preferred a cued strategy relative to control mice. When the training sequence was presented in the reverse order (i.e., place/spatial training before cued training), 5XFAD mice showed impairments in place/spatial training, but no differences in cued training or in the strategy preference test comparing to control. Analysis of regional Aβ42 deposition in brains of 5XFAD mice showed that the hippocampus, which is involved in the place/spatial learning strategy, had the highest levels of Aβ42 and the dorsal striatum, which is involved in cued learning strategy, showed a small increase in Aβ42 levels. The effect of training protocol order on performance, and regional differences in Aβ42 deposition observed in 5XFAD mice, suggest differential functional recruitment of brain structures related to learning in healthy and AD individuals.

  7. Electroacupuncture Treatment Improves Learning-Memory Ability and Brain Glucose Metabolism in a Mouse Model of Alzheimer’s Disease: Using Morris Water Maze and Micro-PET

    Directory of Open Access Journals (Sweden)

    Jing Jiang

    2015-01-01

    Full Text Available Introduction. Alzheimer’s disease (AD causes progressive hippocampus dysfunctions leading to the impairment of learning and memory ability and low level of uptake rate of glucose in hippocampus. What is more, there is no effective treatment for AD. In this study, we evaluated the beneficial and protective effects of electroacupuncture in senescence-accelerated mouse prone 8 (SAMP8. Method. In the electroacupuncture paradigm, electroacupuncture treatment was performed once a day for 15 days on 7.5-month-old SAMP8 male mice. In the normal control paradigm and AD control group, 7.5-month-old SAMR1 male mice and SAMP8 male mice were grabbed and bandaged while electroacupuncture group therapy, in order to ensure the same treatment conditions, once a day, 15 days. Results. From the Morris water maze (MWM test, we found that the treatment of electroacupuncture can improve the spatial learning and memory ability of SAMP8 mouse, and from the micro-PET test, we proved that after the electroacupuncture treatment the level of uptake rate of glucose in hippocampus was higher than normal control group. Conclusion. These results suggest that the treatment of electroacupuncture may provide a viable treatment option for AD.

  8. Learning Concepts, Language, and Literacy in Hybrid Linguistic Codes: The Multilingual Maze of Urban Grade 1 Classrooms in South Africa

    Science.gov (United States)

    Henning, Elizabeth

    2012-01-01

    From the field of developmental psycholinguistics and from conceptual development theory there is evidence that excessive linguistic "code-switching" in early school education may pose some hazards for the learning of young multilingual children. In this article the author addresses the issue, invoking post-Piagetian and neo-Vygotskian…

  9. Barnes maze testing strategies with small and large rodent models.

    Science.gov (United States)

    Rosenfeld, Cheryl S; Ferguson, Sherry A

    2014-02-26

    Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land (Barnes) mazes. Improved performance over sessions or trials is thought to reflect learning and memory of the escape cage/platform location. Considered less stressful than water mazes, the Barnes maze is a relatively simple design of a circular platform top with several holes equally spaced around the perimeter edge. All but one of the holes are false-bottomed or blind-ending, while one leads to an escape cage. Mildly aversive stimuli (e.g. bright overhead lights) provide motivation to locate the escape cage. Latency to locate the escape cage can be measured during the session; however, additional endpoints typically require video recording. From those video recordings, use of automated tracking software can generate a variety of endpoints that are similar to those produced in water mazes (e.g. distance traveled, velocity/speed, time spent in the correct quadrant, time spent moving/resting, and confirmation of latency). Type of search strategy (i.e. random, serial, or direct) can be categorized as well. Barnes maze construction and testing methodologies can differ for small rodents, such as mice, and large rodents, such as rats. For example, while extra-maze cues are effective for rats, smaller wild rodents may require intra-maze cues with a visual barrier around the maze. Appropriate stimuli must be identified which motivate the rodent to locate the escape cage. Both Barnes and water mazes can be time consuming as 4-7 test trials are typically required to detect improved learning and memory performance (e.g. shorter latencies or path lengths to locate the escape platform or cage) and/or differences between experimental groups. Even so, the Barnes maze is a widely employed behavioral assessment measuring spatial navigational abilities and their potential disruption by genetic, neurobehavioral manipulations, or drug

  10. The creativity maze

    DEFF Research Database (Denmark)

    Bourgeois-Bougrine, Samira; Glaveanu, Vlad Petre; Botella, Marion

    2014-01-01

    The present article aims to address a current gap in our understanding of creativity in screenplay writing by focusing on the cognitive, conative, affective, and environmental factors that come into play at different stages in the creative process. It reports a study employing in-depth interviews...... and or treatment), and, finally, intense periods of writing and rewriting the script. These 3 stages, and, in particular, the multiple and concrete decisions to be taken within each one of them, support a vision of the creative process in this domain metaphorically conceptualized as crossing a maze. Creators...

  11. Effects of differential interference with postnatal cerebellar neurogenesis on motor performance, activity level, and maze learning of rats: a developmental study.

    Science.gov (United States)

    Pellegrino, L J; Altman, J

    1979-02-01

    The region of the cerebellum was X-irradiated in infant rats with selected exposure schedules designed to produce animals in which the cerebellar cortex was (a) essentially normal except for agenesis of late forming granule cells with axons situated in the uppermost molecular layer (12--15X), (b) lacking in stellate cells, with a severe reduction in granule cells with axons in the upper molecular layer (8--15X), (c) morphologically disorganized but had only intermediate cell agenesis (4--5X), or (d) disorganized and devoid of practically all postnatally forming interneurons (4--15X). In the first two experiments young adults had to traverse rotating rods that differed in texture and types of obstacles. The 8--15X animals showed no deficits on any of the rods tested. The third study dealt with spontaneous motor performance in the open field at three ages. The 4--5X and 4--15X animals were hypoactive as infants and young adults; this was attributed to their motor deficits. The 8--15X and 12--15X animals were hyperactive in the open field as young adults. The fourth experiment examined intra- and/or intersession habituation. No group differences were found in habituation patterns. In the fifth experiment, using activity wheels, the 4--15X group was hypoactive, and the 8--15X and 12--15X groups were hyperactive as young adults. In the sixth experiment young adults were tested for learning performance in a multiple-unit water maze. The 4--15X group was deficient on single alternation; the 4--5X and 12--15X groups on double alternation. The seventh experiment shed some light on the single alternation deficit of the 4--15X group; only these animals failed to alternate spontaneously in a nonaversive situation. In conclusion, these behavioral results, combined with those of recent morphological investigations, suggest that the cerebellar cortex is hierarchically organized: The basal domain of Purkinje cells and the lower molecular layer are implicated in the coordination of

  12. Memory-Enhancing Activity of Palmatine in Mice Using Elevated Plus Maze and Morris Water Maze

    Directory of Open Access Journals (Sweden)

    Dinesh Dhingra

    2012-01-01

    Full Text Available The present study was designed to evaluate the effect of palmatine on memory of Swiss young male albino mice. Palmatine (0.1, 0.5, 1 mg/kg, i.p. and physostigmine (0.1 mg/kg, i.p. per se were administered for 10 successive days to separate groups of mice. Effect of drugs on learning and memory of mice was evaluated using elevated plus maze and Morris water maze. Brain acetylcholinesterase activity was also estimated. Effect of palmatine on scopolamine- and diazepam-induced amnesia was also investigated. Palmatine (0.5 and 1 mg/kg and physostigmine significantly improved learning and memory of mice, as indicated by decrease in transfer latency using elevated plus maze, and decrease in escape latency during training and increase in time spent in target quadrant during retrieval using Morris water maze. The drugs did not show any significant effect on locomotor activity of the mice. Memory-enhancing activity of palmatine (1 mg/kg was comparable to physostigmine. Palmatine (1 mg/kg significantly reversed scopolamine- and diazepam-induced amnesia in mice. Palmatine and physostigmine also significantly reduced brain acetylcholinesterase activity of mice. Thus, palmatine showed memory-enhancing activity in mice probably by inhibiting brain acetylcholinesterase activity, through involvement of GABA-benzodiazepine pathway, and due to its antioxidant activity.

  13. Cloze, Maze, and Teacher Judgment

    Science.gov (United States)

    Pikulski, John J.; Pikulski, Edna C.

    1977-01-01

    When cloze and maze scores are compared with teacher judgment in establishing the independent, instructional, and fustration levels of students, both techniques tend to overestimate a child's ability. (HOD)

  14. Y-maze Improving in the Power of Learning and Memory Research%Y型电迷宫在学习记忆研究方面的改良

    Institute of Scientific and Technical Information of China (English)

    冯婷; 李峰; 宋月晗; 刘燕; 刘思源

    2012-01-01

    TTo further apply the behavior methods of learning and memory scientifically, we accessed to relevant experimental results in recent years and integrated the problems and solutions in our multiple experiments, and finally summarized and explored the Y-maze's rational application. The experiment equipment, methods, and indicator choice of Y-maze experiment can be further detailed and more scientific. So it is necessary to make further experimental studies and theoretical studies on it%为进一步科学应用学习记忆的行为学方法,通过查阅近几年相关实验研究结果,结合本实验多次操作中遇到的问题及解决方法,总结并探讨Y型电迷宫的合理应用.Y型电迷宫的实验器材、方法以及指标的选择都可以进一步细节化、科学化,所以进一步的实验研究以及理论研究是十分必要的.

  15. Mazes and Maps: Can Young Children Find Their Way?

    Science.gov (United States)

    Jirout, Jamie J.; Newcombe, Nora S.

    2014-01-01

    Games provide important informal learning activities for young children, and spatial game play (e.g., puzzles and blocks) has been found to relate to the development of spatial skills. This study investigates 4- and 5-year-old children's use of scaled and unscaled maps when solving mazes, asking whether an important aspect of spatial…

  16. Level II scour analysis for Bridge 16 (GROTTH00170016) on Town Highway 17, crossing the Wells River, Groton, Vermont

    Science.gov (United States)

    Striker, L.K.; Ivanoff, M.A.

    1997-01-01

    This report provides the results of a detailed Level II analysis of scour potential at structure GROTTH00170016 on Town Highway 17 crossing the Wells River, Groton, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). Results of a Level I scour investigation also are included in Appendix E of this report. A Level I investigation provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and is found in Appendix D.

  17. Correlation between the concentration of serum polychlorinated biphenyls (PCBs) in pregnant cynomolgus monkeys and their offspring's behavioral scores in eye-contact test and finger maze learning test

    Energy Technology Data Exchange (ETDEWEB)

    Negishi, T. [Aoyama Gakuin Univ., Kanagawa (Japan); Takasuga, T. [Shimadzu Techno-Research Inc., Kyoto (Japan); Kawasaki, K. [Hoshi Univ., Tokyo (Japan); Kuroda, Y. [CREST Japan Science and Technology Corp., Saitama (Japan); Yoshikawa, Y. [The Univ. of Tokyo (Japan)

    2004-09-15

    A recent review suggested that pre- or perinatal exposure of developing fetuses to dioxins, the widespread environmental contaminants, such as polychrorinated biphenlys (PCBs), induce the irreversible abnormalities in the functions of central nervous system (CNS) in human. These chemicals can be transferred to each fetus and naonate transplacentally and lactationally in rhesus monkey. Several studies also reported the adverse effect of PCB on CNS development in rodents and monkeys as well as on behavior in rodents and monkeys. In the present study, we show a preliminary data about the correlation between the serum concentrations of PCBs in pregnant cynomolgus monkeys (Macaca fascicularis) and the scores of two behavioral tests, eye-contact test and four-step finger maze test, which evaluate consciousness against human observer and learning ability, respectively, in their offspring. This experimental surveillance system using non-human primates would be useful to predict the risk of PCBs exposure in human fetuses because of the similarities of cynomolgus monkey to human with regard to reproduction, developmental parameter, and others.

  18. Effect of Flavonoids from Broussonetia papyrifera on Learning and Memory in Mice with Morris Water Maze Test%构树黄酮对小鼠学习记忆的影响

    Institute of Scientific and Technical Information of China (English)

    熊燕飞; 吕波; 李政政; 舒思敏; 郑浩

    2012-01-01

    Morris水迷宫在啮齿目动物的空间学习与记忆的研究中被广泛使用.研究表明摄食抗氧化剂能够增强空间学习与记忆能力.本文目的在于研究构树黄酮对昆明小鼠的空间学习与记忆能力的影响.用构树黄酮固体脂质纳米粒对小鼠灌胃4周,然后进行Morris水迷宫测试.与对照组相比,实验组小鼠的各项指标均有显著改善.这表明构树黄酮能显著增强小鼠的空间学习与记忆能力.同时研究还表明构树黄酮对小鼠的生长发育没有影响.%The Morris Water maze (MWM) is a widely used device to investigate spatial learning and memory in rodents.Previous studies involving antioxidant showed that spatial learning and memory were improved afforded by dietary antioxidants.The present study aimed at investigating the efficacy of flavonoids from Broussonetia papyrifera on spatial acquisition and probe trial performance in KM mice.16 young adult male KM mice were randomly separated into 2 groups,a control (CG) and an experimental group (EG).Mice underwent gavage with normal saline (0.9%) and flavonoid-loaded solid lipid nanoparticles (FSLN for short) from B.papyrifera (5 mg/kg/day) with the same volume for 4 weeks,respectively.Then,the MWM test was performed.Our results showed that flavonoids extracted from B.papyrifera significantly augmented the spatial learning and reference memory of mice in the experimental group,which may be ascribed to decreasing the overproduction of free radicals and therefore,retarding oxidative damage.Interestingly,swimming speed of the mice sharply increased latterly albeit there was no difference between the EG and CG.This study also demonstrated that FSLN treatment had no adverse marginal impact on the growth and development of the mice.Collectively,this work indicated that flavonoids from B.papyrifera could improve the spatial learning and reference memory in young adult male KM mice without obvious side effect and be used as potential

  19. Variants of the Morris water maze task to comparatively assess human and rodent place navigation.

    Science.gov (United States)

    Schoenfeld, Robby; Schiffelholz, Thomas; Beyer, Christian; Leplow, Bernd; Foreman, Nigel

    2017-03-01

    Performance in the Morris water maze has been widely used in routine behavioural studies of rodents. Since the advent of computer-based virtual environments, adaptations of the water maze have become available for human research. Despite decades of comparative neuroscience, formal comparisons of human and animal place navigation performance are rare. We studied 36 subjects, 18 young male mice in a Morris water maze and 18 male students in a virtual version. Quantitative measures (escape latencies, distances and platform crossings) indicated no discernable differences between human and rodent performance, reinforcing the task's general validity and its implied cross-species comparability. However, we extracted, using an a priori free classification method, qualitatively different movement patterns for mice and humans, patterns that reflect the probable strategy that individuals might have been using to solve the task. Our results indicated young male students to have most likely solved the maze by means of spatial strategies whereas mice were observed more often to have adopted non-spatial strategies. These differences could be attributed to differences in our maze setups (spatial cues, task instruction, training protocol, motivation) and gave further hints that maze learning depends on many factors. In summary performance on both spatial tasks was equivalent in humans and mice but the kind of maze learning that was used to achieve maximum performance was different. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Glow discharge based device for solving mazes

    Energy Technology Data Exchange (ETDEWEB)

    Dubinov, Alexander E., E-mail: dubinov-ae@yandex.ru; Mironenko, Maxim S.; Selemir, Victor D. [Russian Federal Nuclear Center − All-Russian Scientific and Research Institute of Experimental Physics (RFNC-VNIIEF), Sarov, Nizhni Novgorod region 607188 (Russian Federation); Sarov Institute of Physics and Technology (SarFTI) of National Research Nuclear University “MEPhI,” Sarov, Nizhni Novgorod region 607188 (Russian Federation); Maksimov, Artem N.; Pylayev, Nikolay A. [Russian Federal Nuclear Center − All-Russian Scientific and Research Institute of Experimental Physics (RFNC-VNIIEF), Sarov, Nizhni Novgorod region 607188 (Russian Federation)

    2014-09-15

    A glow discharge based device for solving mazes has been designed and tested. The device consists of a gas discharge chamber and maze-transformer of radial-azimuth type. It allows changing of the maze pattern in a short period of time (within several minutes). The device has been tested with low pressure air. Once switched on, a glow discharge has been shown to find the shortest way through the maze from the very first attempt, even if there is a section with potential barrier for electrons on the way. It has been found that ionization waves (striations) can be excited in the maze along the length of the plasma channel. The dependancy of discharge voltage on the length of the optimal path through the maze has been measured. A reduction in discharge voltage with one or two potential barriers present has been found and explained. The dependency of the magnitude of discharge ignition voltage on the length of the optimal path through the maze has been measured. The reduction of the ignition voltage with the presence of one or two potential barriers has been observed and explained.

  1. [Glass maze in women's leadership].

    Science.gov (United States)

    Barberá Heredia, Ester; Ramos López, Amparo; Candela Agulló, Carlos

    2011-04-01

    Psychological gender discrimination explanations have changed over the past thirty years, becoming more complex in order to obtain a better understanding of the social reality. At the present moment, one of the most interesting research areas is the one referring to the 'glass maze' phenomenon in women's management careers. The main purpose of this work is to reveal the theoretical evolution in an attempt to explain the leadership study from a gender perspective. The consecutive hypotheses, starting with the labour sexual division idea, are becoming more interactive in order to understand the current labour-social situation. Social psychology has underlined the role of beliefs, observed via gender stereotyped roles, prejudiced attitudes against women, sexist and neo-sexist ideology, or masculine, feminine and androgynous identity development. New psychological interpretations insist on the variability of the gender concept, where gender is sometimes observed through men and women's behaviours, and other times through those behaviour expectations. But gender is mainly observed though the power relations between men and women during social interactions in labour organizations.

  2. Cognitive and Neural Determinants of Response Strategy in the Dual-Solution Plus-Maze Task

    Science.gov (United States)

    De Leonibus, Elvira; Costantini, Vivian J. A.; Massaro, Antonio; Mandolesi, Georgia; Vanni, Valentina; Luvisetto, Siro; Pavone, Flaminia; Oliverio, Alberto; Mele, Andrea

    2011-01-01

    Response strategy in the dual-solution plus maze is regarded as a form of stimulus-response learning. In this study, by using an outcome devaluation procedure, we show that it can be based on both action-outcome and stimulus-response habit learning, depending on the amount of training that the animals receive. Furthermore, we show that…

  3. A cold radial maze for long-lasting spatial memory in mice.

    Science.gov (United States)

    Vizi, Sándor; Mansuy, Isabelle M

    2013-03-15

    Here we report the establishment of a novel spatial learning and memory test called the cold radial maze. It is specifically designed for mice, with all conditions tailored to their natural behaviors. The cold radial maze is a dry-land test with easy-to-measure variables that relies on a consistent motivation system and limits the moderately adverse experience to the duration of testing. Training on this maze produces a long-lasting, resistant, and reversible spatial memory in mice in a reproducible way, without introducing undesirable side effects typically produced in other spatial learning tests. This novel behavioral technique may prove useful in studying mouse models of memory impairment-associated human conditions.

  4. Spontaneous Recovery of Human Spatial Memory in a Virtual Water Maze

    Science.gov (United States)

    Luna, David; Martínez, Héctor

    2015-01-01

    The occurrence of spontaneous recovery in human spatial memory was assessed using a virtual environment. In Experiment 1, spatial memory was established by training participants to locate a hidden platform in a virtual water maze using a set of four distal landmarks. In Experiment 2, after learning about the location of a hidden platform, the…

  5. The differential role of alpha1- and alpha5-containing GABA(A) receptors in mediating diazepam effects on spontaneous locomotor activity and water-maze learning and memory in rats.

    Science.gov (United States)

    Savić, Miroslav M; Milinković, Marija M; Rallapalli, Sundari; Clayton, Terry; Joksimović, Sroan; Van Linn, Michael; Cook, James M

    2009-10-01

    The clinical use of benzodiazepines (BZs) is hampered by sedation and cognitive deterioration. Although genetic and pharmacological studies suggest that alpha1- and alpha5-containing GABA(A) receptors mediate and/or modulate these effects, their molecular substrate is not fully elucidated. By the use of two selective ligands: the alpha1-subunit affinity-selective antagonist beta-CCt, and the alpha5-subunit affinity- and efficacy-selective antagonist XLi093, we examined the mechanisms of behavioural effects of diazepam in the tests of spontaneous locomotor activity and water-maze acquisition and recall, the two paradigms indicative of sedative- and cognition-impairing effects of BZs, respectively. The locomotor-activity decreasing propensity of diazepam (significant at 1.5 and 5 mg/kg) was antagonized by beta-CCt (5 and 15 mg/kg), while it tended to be potentiated by XLi093 in doses of 10 mg/kg, and especially 20 mg/kg. Diazepam decreased acquisition and recall in the water maze, with a minimum effective dose of 1.5 mg/kg. Both antagonists reversed the thigmotaxis induced by 2 mg/kg diazepam throughout the test, suggesting that both GABA(A) receptor subtypes participate in BZ effects on the procedural component of the task. Diazepam-induced impairment in the declarative component of the task, as assessed by path efficiency, the latency and distance before finding the platform across acquisition trials, and also by the spatial parameters in the probe trial, was partially prevented by both, 15 mg/kg beta-CCt and 10 mg/kg XLi093. Combining a BZ with beta-CCt results in the near to control level of performance of a cognitive task, without sedation, and may be worth testing on human subjects.

  6. Guiding brine shrimp through mazes by solving reaction diffusion equations

    Science.gov (United States)

    Singal, Krishma; Fenton, Flavio

    Excitable systems driven by reaction diffusion equations have been shown to not only find solutions to mazes but to also to find the shortest path between the beginning and the end of the maze. In this talk we describe how we can use the Fitzhugh-Nagumo model, a generic model for excitable media, to solve a maze by varying the basin of attraction of its two fixed points. We demonstrate how two dimensional mazes are solved numerically using a Java Applet and then accelerated to run in real time by using graphic processors (GPUs). An application of this work is shown by guiding phototactic brine shrimp through a maze solved by the algorithm. Once the path is obtained, an Arduino directs the shrimp through the maze using lights from LEDs placed at the floor of the Maze. This method running in real time could be eventually used for guiding robots and cars through traffic.

  7. The effect of sub-anesthetic and anesthetic ketamine on water maze memory acquisition, consolidation and retrieval.

    Science.gov (United States)

    Moosavi, Maryam; Yadollahi Khales, Golnaz; Rastegar, Karim; Zarifkar, Asadollah

    2012-02-29

    Ketamine, a non-selective inhibitor of NMDA (N-methyl-D-aspartate) channels is used in anesthetic or sub-anesthetic doses to induce analgesia, amnesia, to suppress fear, anxiety and depression. Although the ketamine's effect on memory acquisition is known, its effects on other aspects of memory are controversial. Morris water maze is a task which assesses spatial learning and memory. This study was aimed to assess the ketamine's differential effect on water maze memory acquisition, consolidation and retrieval. Male Sprague-Dawley rats (250-350 g) were trained in water maze single training session. 24h later a probe trial which was consisted of a single trial without platform was done. To assess the effect of ketamine on water maze memory acquisition it was administered before training; to assess its effect on memory consolidation it was administered immediately after training and to assess its effect on memory retrieval it was injected before probe trial. Ketamine both in sub-anesthetic and anesthetic doses impaired water maze memory acquisition, its anesthetic dose but not sub-anesthetic dose impaired memory consolidation and on retrieval stage, both doses deteriorated memory retrieval. It seems that NMDA receptor activity is not just necessary during water maze memory acquisition but also their post-learning reactivation is required to maintain memory consolidation and retrieval.

  8. Orientation of lizards in a Morris water-maze: roles of the sun compass and the parietal eye.

    Science.gov (United States)

    Foà, Augusto; Basaglia, Francesca; Beltrami, Giulia; Carnacina, Margherita; Moretto, Elisa; Bertolucci, Cristiano

    2009-09-15

    The present study examined for the first time whether a Morris water-maze can be used to explore compass and other orientation mechanisms in the ruin lizard Podarcis sicula. In the open field, during sunny days, lizards were individually trained to swim from the center of the water maze onto a hidden platform (the goal), positioned at the periphery of the maze in a single compass direction. The goal was invisible because it was placed just beneath the water surface and the water was rendered opaque. The results showed that lizards learn to swim directly towards the hidden goal under the sun in the absence of visual feature cues. We further examined whether the observed orientation response would be due to lizards learning the spatial position of the goal relative to the sun's azimuth, i.e. to the use of a time-compensated sun compass. Lizards reaching learning criteria were subjected to 6 h clock-shift (fast or slow), and tested for goal orientation in the Morris water-maze. Results demonstrated that the learned orientation response is mediated by a time-compensated sun compass. Further investigations provided direct evidence that in ruin lizards an intact parietal eye is required to perform goal orientation under the sun inside a Morris water-maze, and that other brain photoreceptors, like the pineal or deep brain photoreceptors, are not involved in orientation.

  9. An expert path through a thermo maze

    Science.gov (United States)

    Kustusch, Mary Bridget; Roundy, David; Dray, Tevian; Manogue, Corinne

    2013-01-01

    Several studies in recent years have demonstrated that upper-division students struggle with partial derivatives and the complicated chain rules ubiquitous in thermodynamics. We asked several experts (primarily faculty who teach thermodynamics) to solve a challenging and novel thermodynamics problem in order to understand how they navigate through this maze. What we found was a tremendous variety in solution strategies and sense-making tools, both within and between individuals. This case study focuses on one particular expert: his solution paths, use of sense-making tools, and comparison of different approaches.

  10. The Maze procedure: surgical therapy for refractory atrial fibrillation.

    Science.gov (United States)

    McCarthy, P M; Castle, L W; Trohman, R G; Simmons, T W; Maloney, J D; Klein, A L; White, R D; Cox, J L

    1993-01-01

    Although atrial fibrillation is well tolerated by most patients, in some patients the consequences may be severe. The Maze procedure is a new open-heart operation that creates a carefully designed maze of incisions in the atrial myocardium; this maze then acts as an electrical conduit to channel atrial impulses from the sinoatrial node to the atrioventricular node. The Maze procedure has been shown to restore sinus rhythm and atrial systole (thus reducing the risk of thromboembolism), improve hemodynamics, alleviate palpitations, and eliminate the need for antiarrhythmic and anticoagulant drugs. We describe our first patient to undergo this operation.

  11. Effects of early training and nicotine treatment on the performance of male NMRI mice in the water maze.

    Science.gov (United States)

    Vicens, Paloma; Carrasco, M Carmen; Redolat, Rosa

    2003-01-01

    This research aimed to evaluate the effect of nicotine treatment and prior training on a spatial learning task in differently aged NMRI male mice. In a longitudinal study, mice were randomly assigned to one of 14 experimental groups receiving different combinations of chronically injected nicotine (0.35 mg/kg) administered for 10 days (5 days before and during 5 days acquisition of task) or control treatments and training in the water maze at different ages. The mice displayed shorter escape latencies when evaluated at 6 and 10 months than when tested in this task at 2 months for the first time, demonstrating that early training preserves performance in the water maze up to 8 months after the initial experience. Nicotine treatment did not significantly change performance in the water maze at any age tested. Early practice in a spatial reference memory task appears to have lasting consequences and can potentially contribute to preventing some age-related spatial learning deficits.

  12. Effect of Jiawei Wendan Decoction Regulating Spatial Learning and Memory Capability in Radial Maze of Depression Model Rats%加味温胆汤对抑郁模型大鼠八臂迷宫空间学习记忆能力的影响

    Institute of Scientific and Technical Information of China (English)

    张丽萍; 李庆和; 夏猛; 高健

    2013-01-01

    目的:探讨加味温胆汤对抑郁模型大鼠八臂迷宫空间学习记忆能力的影响.方法:以孤养结合慢性不可预见性应激抑郁模型大鼠为研究对象,在实验第7、14、21、28 d,检测各组大鼠体质量增长数(△W),糖水消耗量,八臂迷宫行为学指标.结果:①体质量增长数变化:21 d,28 d时,与空白组比较,模型组降低(P<0.01);与模型组比较,中、西药组升高(P<0.05或P<0.01).②糖水消耗量变化:21 d,28 d时,与空白组比较,模型组减少(P<0.01);与模型组比较,中、西药组增多(P<0.05或P<0.01).③八臂迷宫行为学变化:21 d,28 d时,模型组大鼠走完八臂迷宫所用时间、错误总数高于空白组(P<0.01),首错前正确数低于空白组(P<0.05或P<0.01),中、西药组大鼠走完八臂迷宫所用时间、错误总数少于模型组(P <0.05或P<0.01),首错前正确数高于模型组(P<0.05或P<0.01).结论:加味温胆汤具有改善抑郁模型大鼠空间学习记忆能力的作用,其治疗效应的变化规律为,21 d显效,随着干预时间的延长,28d时效果进一步增强.%Objective: To explore the effect of Jiawei Wendan Decoction on spatial learning and memory capability in Radial Maze of depression model rats. Methods:Isolated depression model rats,as research objects,lived unpredictable chronic stress. At 7th, 14th ,21st ,28th day of the experiment,we detected increased weight,amount of syrup consumption and behavioral indicators of Radial Maze of each group rats. Results:①Changes of weight; at 21st ,28th day,compared with the blank group,the index of rats' weight was reduced in the model group(P <0. 01) ; but when compared to the model group, the index was increased in Chinese medicine treatment group and western medicine treatment group(P <0. 05 or P <0. 01 ). ② Changes of syrup consumption; at 21 st,28th day, compared to the blank group, the index of syrup consumption was decreased in the model group (P <0. 01

  13. Post-training Inactivation of the Anterior Thalamic Nuclei Impairs Spatial Performance on the Radial Arm Maze

    Science.gov (United States)

    Harvey, Ryan E.; Thompson, Shannon M.; Sanchez, Lilliana M.; Yoder, Ryan M.; Clark, Benjamin J.

    2017-01-01

    The limbic thalamus, specifically the anterior thalamic nuclei (ATN), contains brain signals including that of head direction cells, which fire as a function of an animal's directional orientation in an environment. Recent work has suggested that this directional orientation information stemming from the ATN contributes to the generation of hippocampal and parahippocampal spatial representations, and may contribute to the establishment of unique spatial representations in radially oriented tasks such as the radial arm maze. While previous studies have shown that ATN lesions can impair spatial working memory performance in the radial maze, little work has been done to investigate spatial reference memory in a discrimination task variant. Further, while previous studies have shown that ATN lesions can impair performance in the radial maze, these studies produced the ATN lesions prior to training. It is therefore unclear whether the ATN lesions disrupted acquisition or retention of radial maze performance. Here, we tested the role of ATN signaling in a previously learned spatial discrimination task on a radial arm maze. Rats were first trained to asymptotic levels in a task in which two maze arms were consistently baited across training. After 24 h, animals received muscimol inactivation of the ATN before a 4 trial probe test. We report impairments in post-inactivation trials, suggesting that signals from the ATN modulate the use of a previously acquired spatial discrimination in the radial-arm maze. The results are discussed in relation to the thalamo-cortical limbic circuits involved in spatial information processing, with an emphasis on the head direction signal. PMID:28321178

  14. What is the most sensitive measure of water maze probe test performance?

    Directory of Open Access Journals (Sweden)

    Hamid R Maei

    2009-03-01

    Full Text Available The water maze is commonly used to assay spatial cognition, or, more generally, learning and memory in experimental rodent models. In the water maze, mice or rats are trained to navigate to a platform located below the water’s surface. Spatial learning is then typically assessed in a probe test, where the platform is removed from the pool and the mouse or rat is allowed to search for it. Performance in the probe test may then be evaluated using either occupancy-based (percent time in virtual quadrant [Q] or zone [Z] centered on former platform location, error-based (mean proximity to former platform location [P] or counting-based (platform crossings [X] measures. While these measures differ in their popularity, whether they differ in their ability to detect group differences is not known. To address this question we compiled 5 separate databases, containing more than 1600 mouse probe tests. Random selection of individual trials from respective databases then allowed us to simulate experiments with varying sample and effect sizes. Using this Monte Carlo-based method, we found that the P measure consistently outperformed the Q, Z and X measures in its ability to detect group differences. This was the case regardless of sample or effect size, and using both parametric and non-parametric statistical analyses. The relative superiority of P over other commonly used measures suggests that it is the most appropriate measure to employ in both low- and high-throughput water maze screens.

  15. Cortical gene transcription response patterns to water maze training in aged mice

    Directory of Open Access Journals (Sweden)

    Martin Bronwen

    2011-06-01

    Full Text Available Abstract Background The hippocampus mediates the acquisition of spatial memory, but the memory trace is eventually transferred to the cortex. We have investigated transcriptional activation of pathways related to cognitive function in the cortex of the aged mouse by analyzing gene expression following water maze training. Results We identified genes that were differentially responsive in aged mice with accurate spatial performance during probe trials or repeated swimming sessions, relative to home cage conditions. Effective learners exhibited significantly greater activation of several pathways, such as the mitogen-activated protein kinase and insulin receptor signaling pathways, relative to swimmers. The genes encoding activity-related cytoskeletal protein (Arc and brain-derived neurotrophic factor (BDNF were upregulated in proficient learners, relative to swimmers and home cage controls, while the gene encoding Rho GTPase activating protein 32 (GRIT was downregulated. We explored the regulation of Arc, BDNF, and GRIT expression in greater morphological detail using in situ hybridization. Recall during probe trials enhanced Arc expression across multiple cortical regions involved in the cognitive component of water maze learning, while BDNF expression was more homogeneously upregulated across cortical regions involved in the associational and sensorimotor aspects of water maze training. In contrast, levels of GRIT expression were uniformly reduced across all cortical regions examined. Conclusions These results suggest that cortical gene transcription is responsive to learning in aged mice that exhibit behavioral proficiency, and support a distributed hypothesis of memory storage across multiple cortical compartments.

  16. Cross-species translation of the Morris maze for Alzheimer's disease.

    Science.gov (United States)

    Possin, Katherine L; Sanchez, Pascal E; Anderson-Bergman, Clifford; Fernandez, Roland; Kerchner, Geoffrey A; Johnson, Erica T; Davis, Allyson; Lo, Iris; Bott, Nicholas T; Kiely, Thomas; Fenesy, Michelle C; Miller, Bruce L; Kramer, Joel H; Finkbeiner, Steven

    2016-02-01

    Analogous behavioral assays are needed across animal models and human patients to improve translational research. Here, we examined the extent to which performance in the Morris water maze - the most frequently used behavioral assay of spatial learning and memory in rodents - translates to humans. We designed a virtual version of the assay for human subjects that includes the visible-target training, hidden-target learning, and probe trials that are typically administered in the mouse version. We compared transgenic mice that express human amyloid precursor protein (hAPP) and patients with mild cognitive impairment due to Alzheimer's disease (MCI-AD) to evaluate the sensitivity of performance measures in detecting deficits. Patients performed normally during visible-target training, while hAPP mice showed procedural learning deficits. In hidden-target learning and probe trials, hAPP mice and MCI-AD patients showed similar deficits in learning and remembering the target location. In addition, we have provided recommendations for selecting performance measures and sample sizes to make these assays sensitive to learning and memory deficits in humans with MCI-AD and in mouse models. Together, our results demonstrate that with careful study design and analysis, the Morris maze is a sensitive assay for detecting AD-relevant impairments across species.

  17. Problem-solving in English through business mazes

    CERN Document Server

    Farthing, Joni

    1981-01-01

    We choose our job carefully. What we cannot choose are our colleagues - so it's not surprising that conflict and friction can arise in our working relationships. Business Mazes presents such problems for you to solve. Follow a route through the maze ans see the outcome of each decision you make. You may find that the quickest rout isn't always the best, or the easiest, in the long run. Business Mazes is designed for intermediate and advanced level students of English, working alone or in groups. It includes full teaching plans and exercises. The mazes may also be used effectively as an interesting approach to discussion for young people preparing their first job.

  18. Fast Escape from Quantum Mazes in Integrated Photonics

    CERN Document Server

    Caruso, Filippo; Ciriolo, Anna Gabriella; Sciarrino, Fabio; Osellame, Roberto

    2015-01-01

    Escaping from a complex maze, by exploring different paths with several decision-making branches in order to reach the exit, has always been a very challenging and fascinating task. Wave field and quantum objects may explore a complex structure in parallel by interference effects, but without necessarily leading to more efficient transport. Here, inspired by recent observations in biological energy transport phenomena, we demonstrate how a quantum walker can efficiently reach the output of a maze by partially suppressing the presence of interference. In particular, we show theoretically an unprecedented improvement in transport efficiency for increasing maze size with respect to purely quantum and classical approaches. In addition, we investigate experimentally these hybrid transport phenomena, by mapping the maze problem in an integrated waveguide array, probed by coherent light, hence successfully testing our theoretical results. These achievements may lead towards future bio-inspired photonics technologies...

  19. A Wireless EEG Recording Method for Rat Use inside the Water Maze.

    Directory of Open Access Journals (Sweden)

    Richard C Pinnell

    Full Text Available With the continued miniaturisation of portable embedded systems, wireless EEG recording techniques are becoming increasingly prevalent in animal behavioural research. However, in spite of their versatility and portability, they have seldom been used inside water-maze tasks designed for rats. As such, a novel 3D printed implant and waterproof connector is presented, which can facilitate wireless water-maze EEG recordings in freely-moving rats, using a commercial wireless recording system (W32; Multichannel Systems. As well as waterproofing the wireless system, battery, and electrode connector, the implant serves to reduce movement-related artefacts by redistributing movement-related forces away from the electrode connector. This implant/connector was able to successfully record high-quality LFP in the hippocampo-striatal brain regions of rats as they undertook a procedural-learning variant of the double-H water-maze task. Notably, there were no significant performance deficits through its use when compared with a control group across a number of metrics including number of errors and speed of task completion. Taken together, this method can expand the range of measurements that are currently possible in this diverse area of behavioural neuroscience, whilst paving the way for integration with more complex behaviours.

  20. 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

  1. Short-term versus long-term water maze training effects on hippocampal neuronal synaptic plasticity in a rat model of senile dementia

    Institute of Scientific and Technical Information of China (English)

    Guogui Li

    2008-01-01

    BACKGROUND: Changes in synaptic plasticity might underlie senile dementia, and might be the neurobiological basis for learning and memory dysfunctions in patients with Alzheimer's Disease. OBJECTIVE: To investigate the effects of water maze training on hippocampal neuronal synaptic plasticity in rats with senile dementia, and to compare changes in synaptic plasticity between short- and long-term water maze training sessions.DESIGN, TIME AND SETTING: A randomized, controlled, neuromorphological observation with animal models of senile dementia was performed at the laboratory of College of Pharmacy, Chongqing Medical University between November 2006 and April 2007.MATERIALS: Fifty male, Sprague Dawley rats were randomized into five groups, with 10 rats per group: model, control, sham-operated, short-term water maze training, and long-term water maze training. METHODS: In the model group, senile dementia was induced by fimbria-fornix lesion method. The control rats remained untreated. In the sham-operated group, water maze training was performed without fimbria-fornix lesion induction. Rats from the short-term water maze training group underwent 20-day water maze training from day 26 after fimbria-fornix lesion induction. The long-term water maze training group underwent 40-day water maze training beginning at day 6 following fimbria-fornix lesion induction. Beginning at day 41, each group underwent 5-day spatial learning and memory training. MAIN OUTCOME MEASURES: Following experimentation, the morphological parameters of synapses, including synaptic numerical density, synaptic surface density, and the average synapse size were stereologically measured. Through the use of an electron microscope, synaptic morphological changes in the hippocampai CA3 region were observed.RESULTS: Compared with the control group, synaptic numerical and surface densities were significantly decreased in the model group (P < 0.01). Synaptic numerical and surface densities significantly

  2. Mental walking through a complex maze influences lateralized ultradian rhythms.

    Science.gov (United States)

    Meier-Koll, A; Albrecht, U; Neuschwander, D

    1998-12-01

    Subjects of two experimental groups, 10 males and 10 females in each group, explored artificial environments represented by compact city mazes. The mazes, a simple and a complex one, were generated by means of a computer program. After turning the program on, a scene with houses, streets, and alleys appeared on a TV screen. The subjects sat in front of the screen and manoeuvered through the simple or the complex maze with the help of a hand-operated device. Correspondingly the street scenes changed in such a way that the subject had the illusion of a normal pace. Each subject explored one maze for eight hours. Every 15 min. an experimenter interrupted the subject's walk and measured tactile discrimination in either hand. Ultradian periodic variations in the tactile error rate of the right and left hands with periods of 2 or 3 hours are found. They are considered manifestations of endogenous rhythms operating separately in the left and right cerebral hemispheres. As demonstrated in a previous paper, lateralized ultradian rhythms in tactile discrimination are different for males and females when tested under quiet laboratory conditions. The present paper shows that the rhythms are specifically influenced in both sexes by the spatial complexity of an artificial environment (maze). These findings are discussed from an evolutionary point of view.

  3. [Assessment of an educational maze for major trauma care teaching].

    Science.gov (United States)

    Cuisinier, A; Schilte, C; Declety, P; Baudrant, M; Picard, J; Berger, K; Bouzat, P; Gay, S; Falcon, D; Bosson, J-L; Payen, J-F; Albaladejo, P

    2012-11-01

    Assess efficacy, satisfaction and usefulness of an educational maze based on posters and audioguide for major trauma care teaching to medical students. The educational maze consists of posters with audio comments recorded in an audioguide. This tool was part of a larger educational program including medical simulation. Prospective, interventional, observational, monocentric study. STUDENT: Medical student of Grenoble University Hospital, in the four last years of medical school, following a training course in anesthesia, emergency medical services and intensive care units. Forty essentials key messages for major trauma management were included in 10 posters and audioguides. A first assessment with short opened answers was handed to the students at the end of the educational maze to assess their memorization. A second assessment with simple choice answers regarding satisfaction and usefulness of this new educational tool was realized at the end of the entire program. One hundred and eighty-four medical students attending the major trauma program were included in this study. On the first test, 75% of essential knowledge on major trauma management was memorized by more than 50% of the medical students. On the second test, 94% of medical students had a high satisfaction level of this educational maze. An educational maze based on posters and audioguides seems to be an efficient, useful tool for teaching essential knowledge on major trauma management to medical students. Copyright © 2012. Published by Elsevier SAS.

  4. Intelligence-Augmented Rat Cyborgs in Maze Solving

    Science.gov (United States)

    Yu, Yipeng; Pan, Gang; Gong, Yongyue; Xu, Kedi; Zheng, Nenggan; Hua, Weidong; Zheng, Xiaoxiang; Wu, Zhaohui

    2016-01-01

    Cyborg intelligence is an emerging kind of intelligence paradigm. It aims to deeply integrate machine intelligence with biological intelligence by connecting machines and living beings via neural interfaces, enhancing strength by combining the biological cognition capability with the machine computational capability. Cyborg intelligence is considered to be a new way to augment living beings with machine intelligence. In this paper, we build rat cyborgs to demonstrate how they can expedite the maze escape task with integration of machine intelligence. We compare the performance of maze solving by computer, by individual rats, and by computer-aided rats (i.e. rat cyborgs). They were asked to find their way from a constant entrance to a constant exit in fourteen diverse mazes. Performance of maze solving was measured by steps, coverage rates, and time spent. The experimental results with six rats and their intelligence-augmented rat cyborgs show that rat cyborgs have the best performance in escaping from mazes. These results provide a proof-of-principle demonstration for cyborg intelligence. In addition, our novel cyborg intelligent system (rat cyborg) has great potential in various applications, such as search and rescue in complex terrains. PMID:26859299

  5. Intelligence-Augmented Rat Cyborgs in Maze Solving.

    Directory of Open Access Journals (Sweden)

    Yipeng Yu

    Full Text Available Cyborg intelligence is an emerging kind of intelligence paradigm. It aims to deeply integrate machine intelligence with biological intelligence by connecting machines and living beings via neural interfaces, enhancing strength by combining the biological cognition capability with the machine computational capability. Cyborg intelligence is considered to be a new way to augment living beings with machine intelligence. In this paper, we build rat cyborgs to demonstrate how they can expedite the maze escape task with integration of machine intelligence. We compare the performance of maze solving by computer, by individual rats, and by computer-aided rats (i.e. rat cyborgs. They were asked to find their way from a constant entrance to a constant exit in fourteen diverse mazes. Performance of maze solving was measured by steps, coverage rates, and time spent. The experimental results with six rats and their intelligence-augmented rat cyborgs show that rat cyborgs have the best performance in escaping from mazes. These results provide a proof-of-principle demonstration for cyborg intelligence. In addition, our novel cyborg intelligent system (rat cyborg has great potential in various applications, such as search and rescue in complex terrains.

  6. Intelligence-Augmented Rat Cyborgs in Maze Solving.

    Science.gov (United States)

    Yu, Yipeng; Pan, Gang; Gong, Yongyue; Xu, Kedi; Zheng, Nenggan; Hua, Weidong; Zheng, Xiaoxiang; Wu, Zhaohui

    2016-01-01

    Cyborg intelligence is an emerging kind of intelligence paradigm. It aims to deeply integrate machine intelligence with biological intelligence by connecting machines and living beings via neural interfaces, enhancing strength by combining the biological cognition capability with the machine computational capability. Cyborg intelligence is considered to be a new way to augment living beings with machine intelligence. In this paper, we build rat cyborgs to demonstrate how they can expedite the maze escape task with integration of machine intelligence. We compare the performance of maze solving by computer, by individual rats, and by computer-aided rats (i.e. rat cyborgs). They were asked to find their way from a constant entrance to a constant exit in fourteen diverse mazes. Performance of maze solving was measured by steps, coverage rates, and time spent. The experimental results with six rats and their intelligence-augmented rat cyborgs show that rat cyborgs have the best performance in escaping from mazes. These results provide a proof-of-principle demonstration for cyborg intelligence. In addition, our novel cyborg intelligent system (rat cyborg) has great potential in various applications, such as search and rescue in complex terrains.

  7. Effects of Early Training and Nicotine Treatment on the Performance of Male NMRI Mice in the Water Maze

    OpenAIRE

    2003-01-01

    This research aimed to evaluate the effect of nicotine treatment and prior training on a spatial learning task in differently aged NMRI male mice. In a longitudinal study, mice were randomly assigned to one of 14 experimental groups receiving different combinations of chronically injected nicotine (0.35 mg/kg) administered for 10 days (5 days before and during 5 days acquisition of task) or control treatments and training in the water maze at different ages. The ...

  8. 电针对APP/PS1转基因 AD鼠 Morris水迷宫学习记忆及脑皮层Aβ水平的影响%Effect of Electro-acupuncture on Learning and Memory Behavior in Morris Water Maze and Cerebral Aβin APP/PS1 Transgenic AD Mice

    Institute of Scientific and Technical Information of China (English)

    白杨; 薛卫国; 高亮; 陈默; 辛随成

    2014-01-01

    Objective:To explore the effect of electro -acupuncture on learning and memory behavior and the cerebral cortex Aβlevel in five months APP/PS1 transgenic AD mice .Methods:20 APP/PS1 transgenic posi-tive male mice were randomly divided into a model group and an electro -acupuncture group ,with 10 in each group .At the same time there were 10 APP/PS1 transgenic negative male mice in the normal control group .The electro-acupuncture group was acupunctured at“Baihui”and“Yongquan” ,then was adopted the intervention of electrical needle equipment which was dilatational wave , 15 min at a time ,every other day at a time ,treatment lasted five weeks .Finally the ability of learning and memory of all mice was tested by Morris water maze .Use immunohistochemical imaging to study the levels of cerebral Aβin mice.Results:Escape latency between three groups was statistically significant ( P<0 .05 );the difference between the model group and the electro -acu-puncture group was statistically significant (P<0.05).Expressions of Aβ1-40 and Aβ1-42 of the electro-acupuncture group were lower than those in the model group .Conclusion:Electro-acupuncture can probably improve learning and memory ability of APP/PS1 double transgenic mice through reducing the level of Aβ.%目的:探讨电针对5月龄APP/PS1转基因AD模型鼠学习记忆行为学及脑皮层Aβ水平的影响。方法:20只APP/PS1转基因阳性雄鼠随机分为模型组、电针组,每组各10只,APP/PS1转基因阴性雄鼠10只为对照组,电针组针刺“百会”、“涌泉”后接电针仪,疏密波,每次针刺持续15 min,隔日1次;对照组、模型组以相同方法用鼠袋束缚15 min,隔日1次,3组都持续5周,以Morris水迷宫检测小鼠学习记忆能力,用免疫组化方法检测脑皮层Aβ1-40、Aβ1-42的表达。结果:3组间的逃避潜伏期差异有统计学意义(P<0.05),电针组与模型组之间的差异有统计学意义( P<0

  9. What does the CBM-Maze test measure?

    NARCIS (Netherlands)

    Muijselaar, M.M.L.; Kendeou, P.; Jong, P.F. de; Broek, P.W. van den

    2017-01-01

    In this study, we identified the code-related (decoding, fluency) and language comprehension (vocabulary, listening comprehension) demands of the CBM-Maze test, a formative assessment, and compared them to those of the Gates-MacGinitie test, a standardized summative assessment. The demands of these

  10. Validating the Electric Maze Task as a Measure of Planning

    Science.gov (United States)

    Sheppard, Kelly W.; Cheatham, Carol L.

    2017-01-01

    The Electric Maze Task (EMT) is a novel planning task designed to allow flexible testing of planning abilities across a broad age range and to incorporate manipulations to test underlying planning abilities, such as working-memory and inhibitory control skills. The EMT was tested in a group of 63 typically developing 7- to 12-year-olds.…

  11. What Does the CBM-Maze Test Measure?

    Science.gov (United States)

    Muijselaar, Marloes M. L.; Kendeou, Panayiota; de Jong, Peter F.; van den Broek, Paul W.

    2017-01-01

    In this study, we identified the code-related (decoding, fluency) and language comprehension (vocabulary, listening comprehension) demands of the CBM-Maze test, a formative assessment, and compared them to those of the Gates-MacGinitie test, a standardized summative assessment. The demands of these reading comprehension tests and their…

  12. Maze Busters: Carrie Miyoshi Macfarlane & Kathleen Sheehan--Harvard University

    Science.gov (United States)

    Library Journal, 2004

    2004-01-01

    Even if one is equipped with an MLS, the 11 libraries that comprise the Harvard College Library can be pretty daunting. That is why Carrie Miyoshi Macfarlane and Kathleen Sheehan created Threading the Maze. The online publication is presented to students in expository writing, the one course all undergraduates must take. "This highly effective…

  13. Postoperative metabolic acidosis following the minimally invasive radiofrequency maze procedure

    Directory of Open Access Journals (Sweden)

    Raymond Patrick Hom

    2016-01-01

    Full Text Available Purpose: Atrial fibrillation (AF is the most common arrhythmia treated in the world. While medical treatment with antiarrhythmic drugs remains the primary treatment modality, symptomatic refractory AF often requires treatment with a catheter or surgical ablation. One minimally invasive therapy is the Mini-Maze procedure, which utilizes epicardial radiofrequency ablation via a subxiphoid approach to rid the heart of arrhythmogenic atrial foci without a median sternotomy or cardiopulmonary bypass. The goal of this retrospective cohort study was to identify clinical factors associated with metabolic acidosis following the Mini-Maze procedure. Materials and Methods: After Institutional Review Board approval, we studied patients undergoing the Mini-Maze procedure, off-pump coronary artery bypass grafting or patients conventional Cox-Maze on cardiopulmonary bypass. The first base deficit value obtained in the Intensive Care Unit was used as a measure of metabolic acidosis. Using logistic regression with Akaike information criteria, we analyzed preoperative, intraoperative, and postoperative data to determine the factors associated with changes in base deficit. Results: A multivariable model using stepwise selection demonstrated that diabetes mellitus and weight were associated with a decrease in the base deficit by 2.87 mEq/L (95% CI: −5.55-−0.19 and 0.04 mEq/L (95%CI: −0.08, 0.004, respectively. Furthermore, creatinine was associated with a 1.57 mEq/L (95% CI: 0.14, 2.99 increase in the base deficit. Conclusion: The Mini-Maze procedure was not associated with postoperative metabolic acidosis. Instead, nondiabetic patients and patients with higher creatinine were associated with greater base deficits after undergoing cardiac surgery.

  14. Sex differences in ICR mice in the Morris water maze task.

    Science.gov (United States)

    Ge, J F; Qi, C C; Qiao, J P; Wang, C W; Zhou, N J

    2013-01-01

    The Morris water maze (MWM) is one of the most common tasks used to assess spatial learning and memory ability in rodents. Genetic strain and gender are two prominent variants that influence spatial performance. Although it was reported that ICR (Institute of Cancer Research) mice exhibited an unchanged baseline performance in the training phase of the MWM task, this outbred strain has been widely used in learning and memory studies, and little is known regarding the effects of sex on behavioral performance. In this study, we demonstrated that both male and female ICR mice could complete the MWM task. Furthermore, a significant sex difference was observed, with females having shorter escape latencies and longer durations in the target quadrant in both the acquisition and test phases. Our findings emphasize the necessity of careful examination of not only the strain effect on behavioral performance but also the sex effect.

  15. Spatial Memory in the Morris Water Maze and Activation of Cyclic AMP Response Element-Binding (CREB) Protein within the Mouse Hippocampus

    Science.gov (United States)

    Porte, Yves; Buhot, Marie Christine; Mons, Nicole E.

    2008-01-01

    We investigated the spatio-temporal dynamics of learning-induced cAMP response element-binding protein activation/phosphorylation (pCREB) in mice trained in a spatial reference memory task in the water maze. Using immunohistochemistry, we examined pCREB immunoreactivity (pCREB-ir) in hippocampal CA1 and CA3 and related brain structures. During the…

  16. Event-Centered Maze Generation Method for Mobile Virtual Reality Applications

    Directory of Open Access Journals (Sweden)

    Kisung Jeong

    2016-11-01

    Full Text Available This study proposes a method of effectively creating mobile virtual reality scenes centered at events for the purpose of providing new experiences in virtual reality environment to users. For this purpose, this paper uses Prim’s maze generation algorithm to automatically create maze environments that have different patterns every time and to compute mazes with finite paths. This paper designs a scheme of creating virtual reality scenes based on event-centered mazes to maximize users’ tension and immersion. Here, event components that are appropriate for the maze environment are defined and maze patterns are created centered at the event point where events that are appropriate for the maze pattern are automatically created. Finally, the paper analyzes whether the proposed virtual reality scene based on event-centered mazes is helpful in enhancing users’ immersion and arousing their interest through diverse experiments.

  17. 7-NI and ODQ Disturbs Memory in the Elevated Plus Maze, Morris Water Maze, and Radial Arm Maze Tests in Mice.

    Science.gov (United States)

    Mutlu, Oguz; Akar, Furuzan; Celikyurt, Ipek Komsuoglu; Tanyeri, Pelin; Ulak, Guner; Erden, Faruk

    2015-01-01

    Nitric oxide (NO) is an atypical neurotransmitter that causes changes in cognition. Nitric oxide synthase (NOS) and guanylate cyclase (GC) inhibitors have been shown to exert some effects on cognition in previous studies; however, the findings have been controversial. This study was aimed at understanding the effects of an NOS inhibitor, 7-nitroindazole (7-NI), and a guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), on spatial memory in modified elevated plus maze (mEPM), Morris water maze (MWM), and radial arm maze (RAM) tests. Male Balb-c mice were treated via intraperitoneal injections with 7-NI (15 mg/kg), ODQ (3, 10 mg/kg), L-arginine (100 mg/kg) + 7-NI (15 mg/kg), or physiological saline. ODQ (3 mg/kg) and 7-NI (15 mg/kg) significantly increased the second-day latency in the mEPM test. 7-NI (15 mg/kg) and ODQ (10 mg/kg) significantly increased the escape latency in second, third, and fourth sessions, decreased the time spent in the escape platform's quadrant, and increased the mean distance to the platform in the probe trial of the MWM test. ODQ (3, 10 mg/kg) and 7-NI (15 mg/kg) significantly increased the number of errors, whereas only 7-NI increased the latency in the RAM test. The administration of L-arginine (100 mg/kg) prior to 7-NI inverted the effects of 7-NI, which supports the role of NO on cognition. Our study shows that the NO/cGMP/GS pathway can regulate spatial memory in mice.

  18. Generalizability Theory Analysis of CBM Maze Reliability in Third- through Fifth-Grade Students

    Science.gov (United States)

    Mercer, Sterett H.; Dufrene, Brad A.; Zoder-Martell, Kimberly; Harpole, Lauren Lestremau; Mitchell, Rachel R.; Blaze, John T.

    2012-01-01

    Despite growing use of CBM Maze in universal screening and research, little information is available regarding the number of CBM Maze probes needed for reliable decisions. The current study extends existing research on the technical adequacy of CBM Maze by investigating the number of probes and assessment durations (1-3 min) needed for reliable…

  19. Improving Students’ English Pronunciation Ability Through Go Fish Game and Maze Game

    Directory of Open Access Journals (Sweden)

    Dwi Astuti Wahyu Nurhayati

    2015-12-01

    Full Text Available The problem highlighted in this research is the low pronunciation ability of Kindergarten students in Al-Irsyad  Madiun  that is caused by (1 the uninteresting activities in learning English; (2 the students' difficulties in pronunciating English words; (3 the students' low motivation in learning. The theoretical review includes the young learners characteristics, games in language, games for young learners. The procedure of the research consists of identifying the problem, planning the action, implementing the action, observing the action, and reflecting the result of the research. In this research, the researcher acts as the teacher who conducts the action research in the classroom and she is helped by the classsroom teacher. In collecting the data, the researcher uses observational technique supported with tests. In analyzing the data, the researcher uses the field notes, teacher's diaries, students ‘work supported with the cassette recording and photograph,then also compares the result of the students' pre-test and post-test to answer the research questions. There is significant improvement in the result of pre-test and post-test of cycle 1 and 2. In cycle 1, t0 (2.55734 is higher than tt (1.73 and in cycle 2, t0 (6.765738 is also higher than tt (1.73. From these two results, therefore, h0 is rejected and the alternative hypothesis (ha is accepted. They practice their pronunciation through taking turn and asking each other for cards to match those they have in their hands, arranging a word and sticking on alphabet, pronunciating the word, giving the meaning, hen making a sentence such as Go Fish Game and Maze Game. By conducting these games, using interesting media, creating various interesting tasks and activities can increase the students' motivation in learning English and pronunciation ability.Keywords: Improving, pronunciation, ability,  go fish and Maze games

  20. Initial experience with the maze procedure for atrial fibrillation.

    Science.gov (United States)

    McCarthy, P M; Castle, L W; Maloney, J D; Trohman, R G; Simmons, T W; White, R D; Klein, A L; Cosgrove, D M

    1993-06-01

    From January 1991 until May 1992, a total of 14 patients (mean age 48 years) underwent the maze procedure for refractory atrial fibrillation (mean duration, 7 years; mean number of antiarrhythmic medications, six). Three patients had had embolic events, one patient had had a cardiac arrest from flecainide, one had pulmonary fibrosis from amiodarone, and six of ten who were employed were temporarily disabled. Two patients underwent successful mitral valve repair in which the maze procedure was added as a secondary goal of the operation. Postoperative fluid retention was a problem in five patients (36%). Six patients (43%) were temporarily treated with an antiarrhythmic medication. Two patients (14%) with preoperative sick sinus syndrome required pacemakers. One patient was discharged from the hospital but died suddenly less than 1 month after the operation (7% operative mortality) of hyperkalemia caused by acute renal failure. All patients beyond 3 postoperative months (100% "cure") are receiving no antiarrhythmic medications, have sinus rhythm, or have p-wave tracking with ventricular pacing. Atrial contraction has been documented by cinegraphic magnetic resonance imaging studies and by Doppler echocardiography performed when sinus rhythm had resumed. The maze procedure is an extensive operation but is indicated for selected patients who have the severe sequelae of atrial fibrillation.

  1. Optimal Navigation of Self-Propelled Colloids in Microstructured Mazes

    Science.gov (United States)

    Yang, Yuguang; Bevan, Michael

    Controlling navigation of self-propelled microscopic `robots' subject to random Brownian motion in complex microstructured environments (e.g., porous media, tumor vasculature) is important to many emerging applications (e.g., enhanced oil recovery, drug delivery). In this work, we design an optimal feedback policy to navigate an active self-propelled colloidal rod in complex mazes with various obstacle types. Actuation of the rods is modelled based on a light-controlled osmotic flow mechanism, which produces different propulsion velocities along the rod's long axis. Actuator-parameterized Langevin equations, with soft rod-obstacle repulsive interactions, are developed to describe the system dynamics. A Markov decision process (MDP) framework is used for optimal policy calculations with design goals of colloidal rods reaching target end points in minimum time. Simulations show that optimal MDP-based policies are able to control rod trajectories to reach target regions order-of-magnitudes faster than uncontrolled rods, which diverges as maze complexity increases. An efficient multi-graph based implementation for MDP is also presented, which scales linearly with the maze dimension.

  2. Dietary early-life exposure to contaminated eels does not impair spatial cognitive performances in adult offspring mice as assessed in the Y-maze and the Morris water maze.

    Science.gov (United States)

    Dridi, Imen; Leroy, Delphine; Guignard, Cédric; Scholl, Georges; Bohn, Torsten; Landoulsi, Ahmed; Thomé, Jean-Pierre; Eppe, Gauthier; Soulimani, Rachid; Bouayed, Jaouad

    2014-12-01

    Many environmental contaminants are introduced via the diet and may act as neurotoxins and endocrine disrupters, especially influencing growing organisms in early life. The purpose of this study was to examine whether dietary exposure of dams to fish naturally contaminated with xenobiotics, especially with polychlorinated biphenyls (PCBs) and heavy metals (e.g., mercury and lead), resulted in cognitive function deficits in adult offspring mice. Daily, four groups of dams (n = 10/group) ingested standard diet plus paste with/without eels, during gestation and lactation, from gestational day (GD) six until post natal day (PND) 21 (weaning). Dams orally ingested a standardized amount of eel (0.8 mg kg(-1) d(-1)) containing the six non-dioxin-like (NDL) PCBs (Σ6 NDL-PCBs: 28, 52, 101, 138, 153, and 180) at 0, 85, 216, and 400 ng kg(-1) d(-1). Results showed that early-life exposure to contaminated eels did not (compared to non-exposed controls) impair immediate working memory in the Y-maze in the offspring assessed at PND 38. Furthermore, it did not significantly impact spatial learning and retention memory as measured in the Morris water maze in adult offspring mice (PND 120-123). Our results suggest that perinatal exposure to contaminated eels does not affect spatial cognitive performances, as assessed by the Y-maze and Morris water maze at adult age. Adverse effects of xenobiotics reported earlier might be camouflaged by beneficial eel constituents, such as n-3 fatty acids. However, additional studies are needed to differentiate between potential positive and negative effects following consumption of food items both rich in nutrients and contaminants.

  3. Spatial performance in a complex maze is associated with persistent long-term potentiation enhancement in mouse hippocampal slices at early training stages.

    Science.gov (United States)

    Lange-Asschenfeldt, C; Lohmann, P; Riepe, M W

    2007-06-29

    Long-term potentiation (LTP) and long-term depression (LTD) are principal reflections of synaptic plasticity that have been implicated in learning and memory. We have previously shown that spatial learning in a newly validated complex maze is accompanied by depression of hippocampal CA1 synaptic activity in hippocampal slices of trained mice ("behavioral LTD"). In the present study, we investigated whether behavioral LTD is accompanied by alterations of subsequent LTP induced by high-frequency stimulation (HFS). Moreover, we were interested in the time course of such alterations in relation to training stage. Animals underwent 1, 2, and 8 days of spatial training in the complex maze, respectively. Hippocampal slices were taken 24 h after the last training session. We found a simultaneous decrease of basal synaptic response and increase of HFS induced LTP magnitude compared with slices of untrained animals. Synaptic plasticity was not influenced by repeated running wheel exercise in an additional control group without spatial learning. The mentioned alterations occurred already after day 2 of maze exploration parallel to the most pronounced improvement of behavioral performance but did not change thereafter until day 8 despite further learning progress. They were also found when animals were trained for 2 days and kept at rest for a subsequent 6 days. In conclusion, spatial learning may be reflected by distinct and persistent measurable alterations of synaptic plasticity in hippocampal CA1 neurons at early training stages.

  4. Searching for cognitive enhancement in the Morris water maze: better and worse performance in D-amino acid oxidase knockout (Dao(-/-)) mice.

    Science.gov (United States)

    Pritchett, David; Taylor, Amy M; Barkus, Christopher; Engle, Sandra J; Brandon, Nicholas J; Sharp, Trevor; Foster, Russell G; Harrison, Paul J; Peirson, Stuart N; Bannerman, David M

    2016-04-01

    A common strategy when searching for cognitive-enhancing drugs has been to target the N-methyl-d-aspartate receptor (NMDAR), given its putative role in synaptic plasticity and learning. Evidence in favour of this approach has come primarily from studies with rodents using behavioural assays like the Morris water maze. D-amino acid oxidase (DAO) degrades neutral D-amino acids such as D-serine, the primary endogenous co-agonist acting at the glycine site of the synaptic NMDAR. Inhibiting DAO could therefore provide an effective and viable means of enhancing cognition, particularly in disorders like schizophrenia, in which NMDAR hypofunction is implicated. Indirect support for this notion comes from the enhanced hippocampal long-term potentiation and facilitated water maze acquisition of ddY/Dao(-) mice, which lack DAO activity due to a point mutation in the gene. Here, in Dao knockout (Dao(-/-) ) mice, we report both better and worse water maze performance, depending on the radial distance of the hidden platform from the side wall of the pool. Dao(-/-) mice displayed an increased innate preference for swimming in the periphery of the maze (possibly due to heightened anxiety), which facilitated the discovery of a peripherally located platform, but delayed the discovery of a centrally located platform. By contrast, Dao(-/-) mice exhibited normal performance in two alternative assays of long-term spatial memory: the appetitive and aversive Y-maze reference memory tasks. Taken together, these results question the proposed relationship between DAO inactivation and enhanced long-term associative spatial memory. They also have generic implications for how Morris water maze studies are performed and interpreted.

  5. Cows in the Maze And other mathematical explorations

    CERN Document Server

    Stewart, Ian

    2010-01-01

    From the mathematics of mazes, to cones with a twist, and the amazing sphericon - and how to make one - Ian Stewart is back with more mathematical stories and puzzles that are as quirky as they are fascinating, and each from the cutting edge of the world of mathematics. We find out about the mathematics of time travel, explore the shape of teardrops (which are not tear-drop shaped, but something much, much more strange!), dance with dodecahedra, and play the game of Hex, amongst many more strange and delightful mathematical diversions.

  6. Development and validation of a sensitive entropy-based measure for the water maze

    Directory of Open Access Journals (Sweden)

    Hamid R Maei

    2009-12-01

    Full Text Available In the water maze, mice are trained to navigate to an escape platform located below the water’s surface, and spatial learning is most commonly evaluated in a probe test in which the platform is removed from the pool. While contemporary tracking software provides precise positional information of mice for the duration of the probe test, existing performance measures (e.g., percent quadrant time, platform crossings fail to exploit fully the richness of this positional data. Using the concept of entropy [H], here we develop a new measure that considers both how focused the search is and the degree to which searching is centered on the former platform location. To evaluate how H performs compared to existing measures of water maze performance we compiled 5 separate databases, containing more than 1600 mouse probe tests. Random selection of individual trials from respective databases then allowed us to simulate experiments with varying sample and effect sizes. Using this Monte Carlo-based method, we found that H outperformed existing measures in its ability to detect group differences over a range of sample or effect sizes. Additionally, we validated the new measure using three models of experimentally-induced hippocampal dysfunction: 1 complete hippocampal lesions, 2 genetic deletion of αCaMKII, a gene implicated in hippocampal behavioral and synaptic plasticity, and 3 a mouse model of Alzheimer’s disease. Together, these data indicate that H offers greater sensitivity than existing measures, most likely because it exploits the richness of the precise positional information of the mouse throughout the probe test.

  7. Evidence of population-level lateralized behaviour in giant water bugs, Belostoma flumineum Say (Heteroptera: Belostomatidae): T-maze turning is left biased.

    Science.gov (United States)

    Kight, Scott L; Steelman, Laura; Coffey, Gena; Lucente, Julie; Castillo, Marianne

    2008-09-01

    Lateralized behaviour occurs in diverse animals, but relatively few studies examine the phenomenon in invertebrates. Here we report a population-level left turn bias in the giant water bug Belostoma flumineum Say (Heteroptera: Belostomatidae) in an underwater T-maze. Individuals made significantly more left turns than right turns, including when they were naïve and first introduced to the maze. Water bugs also showed significantly longer runs of consecutive left turns than right turns (i.e. LLLLL). The length of these runs, however, did not increase with experience in the maze, suggesting that the effect is not the result of learning. There were also no differences in turning bias between male and female water bugs. The proximate mechanism(s) underlying the left turn bias is unknown, but directional cues in the environment were eliminated by rotating the maze 180 degrees between experiments, suggesting the mechanism(s) is endogenous. To our knowledge this is the first study of lateralized behaviour in the Heteroptera or in a swimming invertebrate animal.

  8. Effects of an early experience involving training in a T-maze under either denial or receipt of expected reward through maternal contact.

    Directory of Open Access Journals (Sweden)

    Antonios eStamatakis

    2013-11-01

    Full Text Available The mother is the most salient stimulus for the developing pups and a number of early experience models employ manipulation of the mother-infant interaction. We have developed a new model which in addition to changes in maternal behavior includes a learning component on the part of the pups. More specifically, pups were trained in a T-maze and either received (RER rats or were denied (DER the reward of maternal contact, during postnatal days 10—13.Pups of both experimental groups learn the T-maze, but the RER do so more efficiently utilizing a procedural-type of learning and memory with activation of the dorsal basal ganglia. On the other hand, the DER experience leads to activation of the hippocampus, prefrontal cortex and amygdala in the pups.In adulthood, male DER animals exhibit better mnemonic abilities in the Morris water maze and higher activation of the hippocampus, while they have decreased brain serotonergic activity, exhibit a depressive-like phenotype and proactive aggressive behavior in the resident-intruder test. On the other hand, male RER animals assume a reactive coping style in this test, showed increased emotionality as well as freezing in the memory test following both contextual and cued fear conditioning.

  9. Results of clinical application of the modified maze procedure as concomitant surgery

    NARCIS (Netherlands)

    R.C. Bakker (Robbert); S. Akin (Sakir); D. Rizopoulos (Dimitris); C. Kik (Charles); J.J.M. Takkenberg (Hanneke); A.J.J.C. Bogers (Ad)

    2013-01-01

    textabstractObjectives Atrial fibrillation is the most common cardiac arrhythmia and is associated with significant morbidity and mortality. The classic cut-and-sew maze procedure is successful in 85-95% of patients. However, the technical complexity has prompted modifications of the maze procedure.

  10. Mini-maze suffices as adjunct to mitral valve surgery in patients with preoperative atrial fibrillation

    NARCIS (Netherlands)

    Tuinenburg, AE; Van Gelder, IC; Tieleman, RG; Grandjean, JG; Huet, RCG; Van der Maaten, JMAA; Pieper, EG; De Kam, PJ; Ebels, MSCT; Crijns, HJGM

    2000-01-01

    Mini-Maze and Mitral Valve Surgery. Introduction: After mitral valve (MV) surgery, preoperative atrial fibrillation (AF) often recurs while cardioversion therapy generally fails. Additional Cox maze surgery improves postoperative arrhythmia outcome, but the extensive nature of such an approach limit

  11. Effects of Amphetamine and β-Endorphin Fragments on Maze Performance in Rats

    NARCIS (Netherlands)

    Boer, S. de; Bohus, B.

    1990-01-01

    Fragments of β-endorphin and amphetamine cause similar effects in some tests of maze behavior in rats. The present study served to compare the influence of amphetamine and two β-endorphin fragments [β-endorphin (βE)-(2-9) and βE-(2-16)] on maze behavior in more detail. In Experiment I no significant

  12. Effects of amphetamine and beta-endorphin fragments on maze performance in rats

    NARCIS (Netherlands)

    Bohus, B; de Boer, S.F.

    1990-01-01

    Fragments of beta-endorphin and amphetamine cause similar effects in some tests of maze behavior in rats. The present study served to compare the influence of amphetamine and two beta-endorphin fragments [beta-endorphin (beta E)-(2-9) and beta E-(2-16)] on maze behavior in more detail. In Experiment

  13. An automated maze task for assessing hippocampus-sensitive memory in mice.

    Science.gov (United States)

    Pioli, Elsa Y; Gaskill, Brianna N; Gilmour, Gary; Tricklebank, Mark D; Dix, Sophie L; Bannerman, David; Garner, Joseph P

    2014-03-15

    Memory deficits associated with hippocampal dysfunction are a key feature of a number of neurodegenerative and psychiatric disorders. The discrete-trial rewarded alternation T-maze task is highly sensitive to hippocampal dysfunction. Normal mice have spontaneously high levels of alternation, whereas hippocampal-lesioned mice are dramatically impaired. However, this is a hand-run task and handling has been shown to impact crucially on behavioural responses, as well as being labour-intensive and therefore unsuitable for high-throughput studies. To overcome this, a fully automated maze was designed. The maze was attached to the mouse's home cage and the subject earned all of its food by running through the maze. In this study the hippocampal dependence of rewarded alternation in the automated maze was assessed. Bilateral hippocampal-lesioned mice were assessed in the standard, hand-run, discrete-trial rewarded alternation paradigm and in the automated paradigm, according to a cross-over design. A similarly robust lesion effect on alternation performance was found in both mazes, confirming the sensitivity of the automated maze to hippocampal lesions. Moreover, the performance of the animals in the automated maze was not affected by their handling history whereas performance in the hand-run maze was affected by prior testing history. By having more stable performance and by decreasing human contact the automated maze may offer opportunities to reduce extraneous experimental variation and therefore increase the reproducibility within and/or between laboratories. Furthermore, automation potentially allows for greater experimental throughput and hence suitability for use in assessment of cognitive function in drug discovery.

  14. Angiotensin II AT1 receptor blockade by telmisartan reduces impairment of spatial maze performance induced by both acute and chronic stress.

    Science.gov (United States)

    Wincewicz, Dominik; Braszko, Jan J

    2015-09-01

    Despite recognition of stress as a causation of severe neuropsychological dysfunctions, no casual and clinically effective anti-stress therapeutic strategy has yet been found. We have previously shown that blockade of initial stress response by angiotensin receptor blockers alleviates the negative effect of prolonged stress on cognitive non-spatial functions of rats. Here we aimed to find whether telmisartan reduces stress-related memory decline in spatial hippocampal-dependent learning tasks conditioned upon differences in level of stress induced by aversive nature of memory tests. Male Wistar rats were exposed to chronic restraint stress for three weeks and daily treated with either vehicle or telmisartan (1 mg/kg). Afterwards rats were tested in three spatial learning and memory paradigms: Morris water maze (MWM), radial arm maze (RAM), and Barnes maze (BM). Stressed animals demonstrated significantly impaired performance in all the tests, which was normalized in the animals stressed and treated with telmisartan. Interestingly, despite the fact that MWM and RAM are more stressful, which affects animal behavior, therefore considered less sensitive than BM, more significant effect of telmisartan was found in MWM and RAM than BM. AT1 angiotensin receptor blockade attenuates negative effect of both acute and chronic stress on spatial memory. © The Author(s) 2014.

  15. Characterization of the rat exploratory behavior in the elevated plus-maze with Markov chains.

    Science.gov (United States)

    Tejada, Julián; Bosco, Geraldine G; Morato, Silvio; Roque, Antonio C

    2010-11-30

    The elevated plus-maze is an animal model of anxiety used to study the effect of different drugs on the behavior of the animal. It consists of a plus-shaped maze with two open and two closed arms elevated 50cm from the floor. The standard measures used to characterize exploratory behavior in the elevated plus-maze are the time spent and the number of entries in the open arms. In this work, we use Markov chains to characterize the exploratory behavior of the rat in the elevated plus-maze under three different conditions: normal and under the effects of anxiogenic and anxiolytic drugs. The spatial structure of the elevated plus-maze is divided into squares, which are associated with states of a Markov chain. By counting the frequencies of transitions between states during 5-min sessions in the elevated plus-maze, we constructed stochastic matrices for the three conditions studied. The stochastic matrices show specific patterns, which correspond to the observed behaviors of the rat under the three different conditions. For the control group, the stochastic matrix shows a clear preference for places in the closed arms. This preference is enhanced for the anxiogenic group. For the anxiolytic group, the stochastic matrix shows a pattern similar to a random walk. Our results suggest that Markov chains can be used together with the standard measures to characterize the rat behavior in the elevated plus-maze.

  16. Planning in human children (Homo sapiens) assessed by maze problems on the touch screen.

    Science.gov (United States)

    Miyata, Hiromitsu; Itakura, Shoji; Fujita, Kazuo

    2009-02-01

    The authors examined how human children perform on maze tasks on the touch screen and whether the children plan the solution of the mazes. In Experiment 1, the authors exposed children around 3 years of age to a maze having an L-shaped line as a barrier that can be solved by moving an illustration of a dog (the target) to that of a bone (the goal) with their fingers. The participants successfully solved the maze by taking efficient routes more frequently than chance, although the authors found no evidence that a preview of the maze before starting to solve the task facilitated their performance. In Experiment 2, using a plus-shaped maze, the authors found that 3- and 4-year-old children plan and adjust their moves while solving the maze, with 4-year-olds showing more advanced and higher-level planning than 3-year-olds. Similarity of these results to what the authors previously found in pigeons tested in the same tasks may suggest an analogy for planning capacity in the behavioral level across taxa and developmental stages.

  17. Nicotine improves AF64A-induced spatial memory deficits in Morris water maze in rats.

    Science.gov (United States)

    Yamada, Kazuo; Furukawa, Satoshi; Iwasaki, Tsuneo; Ichitani, Yukio

    2010-01-18

    Ethylcholine mustard aziridinium ion (AF64A) is a neurotoxic derivative of choline that produces not only long-term presynaptic cholinergic deficits, but also various memory deficits in rats similar to some characteristics observed in Alzheimer's disease patients. This study investigated whether nicotine (NCT) administration attenuated spatial learning deficits induced by intracerebroventricular AF64A treatment. AF64A (6 nmol/6 microl)-or saline (SAL)-treated rats were trained in Morris water maze task. NCT (0.025-0.25mg/kg) was subcutaneously injected 5 min before the training every day. The results showed that moderate dose (0.10mg/kg) of NCT attenuated AF64A-induced prolongation of escape latency. Furthermore, NCT dose-dependently recovered the AF64A-induced decrease of time spent in the target quadrant in the probe test. These results suggest that NCT improves AF64A-induced spatial memory deficits, and thus it is a potential therapeutic agent for the treatment of memory deficits in dementia.

  18. Effects of intracerebroventricular injection of alpha-fluoromethylhistidine on radial maze performance in rats.

    Science.gov (United States)

    Chen, Z; Sugimoto, Y; Kamei, C

    1999-11-01

    The effects of alpha-fluoromethylhistidine (alpha-FMH) on spatial cognition were investigated using the eight-arm radial maze paradigm in rats. Intracerebroventricular (ICV) injection of alpha-FMH resulted in spatial memory deficits characterized by an increase in the number of total errors (TE) and a decrease in the number of initial correct responses (ICR). There was a strong correlation between increases in the number of TE and decreases in histamine contents of the cortex and hippocampus regions of the brain, which are known to participate in learning and memory. On the other hand, both histamine (50-100 ng, ICV) and thioperamide (10 microg, ICV) significantly ameliorated the memory deficit induced by alpha-FMH. However, metoprine showed no significant effect on the alpha-FMH-induced memory deficit. Pyrilamine and R-(alpha)-methylhistamine enhanced the memory deficit induced by alpha-FMH, at doses that had no appreciable effect when administered alone. In contrast, no significant influence on alpha-FMH-induced memory deficit was observed with zolantidine.

  19. Intracerebellar vermis histamine facilitates memory consolidation in the elevated T maze model.

    Science.gov (United States)

    Silva-Marques, Bruna; Gianlorenço, Anna Carolyna Lepesteur; Mattioli, Rosana

    2016-05-01

    Experimental evidence suggests that the cerebellum plays a more complex role in learning than simply regulating the motor response. Rather, it is thought to play a significant role in the consolidation of emotional memory in mice. Due to the difficulty of interpreting fear and anxiety behaviors-the standard methodology for the study of the histaminergic system and emotional memory-in mice, we propose a behavioral assessment of mice subjected to the Elevated T-maze after histamine microinjection of the cerebellar vermis. Young male Swiss albino mice weighing 25-35g were used. In addition, locomotor activity was tested in an open field test. Our data suggest that histamine did not affect memory consolidation during escape or open field behavior at the doses used in this study. However, we observed a significant increase in inhibitory avoidance on the second day in animals receiving a dose of 6.8nmol/0.5μl, suggesting that histamine facilitates the consolidation of inhibitory avoidance in mice.

  20. Unicursal random maze tool path for computer-controlled optical surfacing.

    Science.gov (United States)

    Wang, Chunjin; Wang, Zhenzhong; Xu, Qiao

    2015-12-01

    A novel unicursal random maze tool path is proposed in this paper, which can not only implement uniform coverage of the polishing surfaces, but also possesses randomness and multidirectionality. The simulation experiments along with the practical polishing experiments are conducted to make the comparison of three kinds of paths, including maze path, raster path, and Hilbert path. The experimental results validate that the maze path can warrant uniform polishing and avoid the appearance of the periodical structures in the polished surface. It is also more effective than the Hilbert path in restraining the mid-spatial frequency error in computer-controlled optical surfacing process.

  1. Spatial learning by mice in three dimensions.

    Science.gov (United States)

    Wilson, Jonathan J; Harding, Elizabeth; Fortier, Mathilde; James, Benjamin; Donnett, Megan; Kerslake, Alasdair; O'Leary, Alice; Zhang, Ningyu; Jeffery, Kate

    2015-08-01

    We tested whether mice can represent locations distributed throughout three-dimensional space, by developing a novel three-dimensional radial arm maze. The three-dimensional radial maze, or "radiolarian" maze, consists of a central spherical core from which arms project in all directions. Mice learn to retrieve food from the ends of the arms without omitting any arms or re-visiting depleted ones. We show here that mice can learn both a standard working memory task, in which all arms are initially baited, and also a reference memory version in which only a subset are ever baited. Comparison with a two-dimensional analogue of the radiolarian maze, the hexagon maze, revealed equally good working-memory performance in both mazes if all the arms were initially baited, but reduced working and reference memory in the partially baited radiolarian maze. This suggests intact three-dimensional spatial representation in mice over short timescales but impairment of the formation and/or use of long-term spatial memory of the maze. We discuss potential mechanisms for how mice solve the three-dimensional task, and reasons for the impairment relative to its two-dimensional counterpart, concluding with some speculations about how mammals may represent three-dimensional space.

  2. Tetrachlorodibenzo-p-dioxin exposure alters radial arm maze performance and hippocampal morphology in female AhR mice.

    Science.gov (United States)

    Powers, B E; Lin, T-M; Vanka, A; Peterson, R E; Juraska, J M; Schantz, S L

    2005-02-01

    Perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter spatial learning in rats tested on a radial arm maze (RAM). TCDD is believed to exert most of its effects through binding to the aryl hydrocarbon receptor (AhR). To determine whether the AhR mediates TCDD-induced alterations in spatial learning, we tested male and female AhR-knockout (AhR-/-), heterozygous (AhR+/-) and wild-type (AhR+/+) mice on the RAM. AhR+/- male and female mice were time mated, and treated dams were dosed with 5 microg TCDD/kg body weight on day 13 of gestation. When offspring reached adulthood, male and female AhR+/+, AhR+/- and AhR-/- mice from TCDD-exposed and unexposed litters were tested on the eight-arm RAM. After testing, we examined hippocampal morphology as visualized by the Timm's silver sulfide stain. TCDD-exposed female AhR+/- mice made more errors than their respective controls on the RAM and exhibited a decrease in the size of the intra- and infrapyramidal mossy fiber (IIP-MF) field of the hippocampus. None of the other TCDD-exposed groups differed from their respective control groups with regard to maze performance or hippocampal morphology. The reduction of IIP-MF field indicates a possible morphological basis for the learning deficit that was observed in the female AhR+/- mice. It is hypothesized that the effect of TCDD exposure is AhR dependent and that TCDD may alter GABAergic activity in the hippocampus of female mice during development.

  3. Slime mould solves maze in one pass ... assisted by gradient of chemo-attractants

    CERN Document Server

    Adamatzky, Andrew

    2011-01-01

    Plasmodium of Physarum polycephalum is a large cell, visible by unaided eye, which exhibits sophisticated patterns of foraging behaviour. The plasmodium's behaviour is well interpreted in terms of computation, where data are spatially extended configurations of nutrients and obstacles, and results of computation are networks of protoplasmic tubes formed by the plasmodium. In laboratory experiments and numerical simulation we show that if plasmodium of Physarum is inoculated in a maze's peripheral channel and an oat flake (source of attractants) in a the maze's central chamber then the plasmodium grows toward target oat flake and connects the flake with the site of original inoculation with a pronounced protoplasmic tube. The protoplasmic tube represents a path in the maze. The plasmodium solves maze in one pass because it is assisted by a gradient of chemo-attractants propagating from the target oat flake.

  4. Active Brownian particles and run-and-tumble particles separate inside a maze

    Science.gov (United States)

    Khatami, Maryam; Wolff, Katrin; Pohl, Oliver; Ejtehadi, Mohammad Reza; Stark, Holger

    2016-11-01

    A diverse range of natural and artificial self-propelled particles are known and are used nowadays. Among them, active Brownian particles (ABPs) and run-and-tumble particles (RTPs) are two important classes. We numerically study non-interacting ABPs and RTPs strongly confined to different maze geometries in two dimensions. We demonstrate that by means of geometrical confinement alone, ABPs are separable from RTPs. By investigating Matryoshka-like mazes with nested shells, we show that a circular maze has the best filtration efficiency. Results on the mean first-passage time reveal that ABPs escape faster from the center of the maze, while RTPs reach the center from the rim more easily. According to our simulations and a rate theory, which we developed, ABPs in steady state accumulate in the outermost region of the Matryoshka-like mazes, while RTPs occupy all locations within the maze with nearly equal probability. These results suggest a novel technique for separating different types of self-propelled particles by designing appropriate confining geometries without using chemical or biological agents.

  5. EFFECTS OF 5, 7-DIHYDROXYTRYPTAMINE-INDUCED DEPLETION OF BRAIN SEROTONIN ON RADIAL ARM-MAZE TASK IN RATS

    Directory of Open Access Journals (Sweden)

    Vasile Hefco

    2005-08-01

    Full Text Available Adult rats pretreated with desipramine (25 mg/kg i.p.30 min before anesthesia in order to protect noradrenergic system, were subjected to intracerebroventriculare injection of 5, 7 –dihydroxytryptamine (5, 7-DHT, 150 μg, 4.5 μl/ventricle, a chronic neurotoxin of the central serotonergic function. After 1.5 months later, we assessed the working memory and reference memory in radial 8 arm-mazes. Serotonergic depletion impaired more significantly shortterm memory tested by means of the average working memory errors, entries to repeat and average time taken to consume all five baits during 12 days training. Long-term memory, explored by means of reference memory errors, was less impaired. It is concluded that serotonin, among other neurotransmitters, play one important role in cognitive functions, including learning and memory.

  6. Individual and combined manipulation of muscarinic, NMDA, and benzodiazepine receptor activity in the water maze task: implications for a rat model of Alzheimer dementia.

    Science.gov (United States)

    Cain, D P; Ighanian, K; Boon, F

    2000-06-15

    Recent evidence indicates that Alzheimer disease typically involves different degrees of impairment in a variety of neurotransmitter systems, behaviors, and cognitive abilities in different patients. To investigate the relations between neurotransmitter system, behavioral, and cognitive impairments in an animal model of Alzheimer disease we studied spatial learning in a Morris water maze in male Long-Evans rats given neurochemical agents that targeted muscarinic cholinergic, NMDA, or benzodiazepine systems. Naive rats given a single agent or a combination of agents were severely impaired in place responding and had behavioral strategy impairments. Rats made familiar with the required water maze behavioral strategies by non-spatial pretraining performed as well as controls if given a single agent. Non-spatially pretrained rats with manipulation of both muscarinic cholinergic and NMDA or muscarinic cholinergic and benzodiazepine systems had a specific place response impairment but no behavioral strategy impairments. The results suggest that impairment of both muscarinic cholinergic and NMDA, or muscarinic cholinergic and benzodiazepine systems may model some aspects of human Alzheimer disease (impairments in navigation in familiar environments), but not other aspects of this disorder (global dementia leading to general loss of adaptive behavior). Previous research suggests that impairment of both muscarinic cholinergic and serotonergic systems may provide a better model of global dementia. The water maze testing and detailed behavioral analysis techniques used here appear to provide a means of investigating the contributions of various combinations of neurotransmitter system impairments to an animal model of Alzheimer disease.

  7. Daily running promotes spatial learning and memory in rats.

    Science.gov (United States)

    Alaei, Hojjatallah; Moloudi, Rohallah; Sarkaki, Ali Reza; Azizi-Malekabadi, Hamid; Hanninen, Osmo

    2007-01-01

    Previous studies have shown that physical activity improves learning and memory. Present study was performed to determine the effects of acute, chronic and continuous exercise with different periods on spatial learning and memory recorded as the latency and length of swim path in the Morris water maze testing in subsequent 8 days. Four rat groups were included as follows: 1- Group C (controls which did not exercise). 2- Group A (30 days treadmill running before and 8 days during the Morris water maze testing period). 3- Group B (30 days exercise before the Morris water maze testing period only) and 4- Group D (8 days exercise only during the Morris water maze testing period). The results showed that chronic (30 days) and continuous (during 8 days of Morris water maze testing days) treadmill training produced a significant enhancement in spatial learning and memory which was indicated by decreases in path length and latency to reach the platform in the Morris water maze test (p learning and memory in Morris water maze, but the benefits were lost in few days without daily running sessions in adult rats. Key pointsDaily running influence on spatial memory.The velocity of learning can be influenced by running activity.Path length is important parameter for measuring the speed of learning.

  8. Characterization of Maze Performance in Adrenalectomized Sleep Disrupted Rats: A Comparison of Radial Arm Maze Performance between Adrenalectomized and Sham Adrenalectomized Sleep Disrupted Rats

    Science.gov (United States)

    2007-01-01

    associated with an increase in orexin , which is also increased by sleep disruption. The Barnes maze does not require food restriction, because the...another behavioral test that detects hippocampal impairments eliminating of food restriction. Food restriction increases corticosterone and orexin

  9. Developing Box Plots While Navigating the Maze of Data Representations

    Science.gov (United States)

    Duncan, Bruce; Fitzallen, Noleine

    2013-01-01

    The learning sequence described in this article was developed to provide students with a demonstration of the development of box plots from authentic data as an illustration of the advantages gained from using multiple forms of data representation. The sequence follows an authentic process that starts with a problem to which data representations…

  10. Distribution of phosphorylated Elk-1 in rat brain after Y-maze active avoidance training in a temporal manner

    Institute of Scientific and Technical Information of China (English)

    Xuhong Chen; Siyun Shu; Zhenjiang Liang; Xinmin Bao; Lixue Chen; Yongming Wu

    2006-01-01

    BACKGROUND: Elk-1 mRNA distributes extensively in the neurons of mice, rat and human brains, and the Elk-1 expression may be correlated with the synaptic plasticity, learning and memory.OBJECTIVE: To observe the distribution of phosphorylated Elk-1 (pElk-1) in whole brain of rats received Y-maze active avoidance training and the changes of pElk-1 expression at different time points after training.DESIGN: A randomized controlled study.SETTING: Research Room of Neurobiology, the Second Affiliated Hospital of Southern Medical University.MATERIALS: Fifty-five male clean-degree SD rats of 3-4 months old, weighing 200-250 g, were provided by the Experimental Animal Center of Southern Medical University. The rabbit anti-monoclonal pElk-1 antibody was purchased from Cell Signal Transduction Company, and ABC kit from Vector Company.METHODS: The experiments were carried out in the Research Room of Neurobiology, Second Affiliated Hospital of Southern Medical University from September 2004 to February 2005. ① Grouping: The rats were randomly divided into training group (n = 25), sham-training group (n = 25) and norm al control group (n = 5), and the training and sham-training groups were observed at 0, 1, 3, 6 and 24 hours after training, which represented the five phases in the process of learning and memory. ② Y-maze training: The rats were preconditioned in the electrical Y-maze apparatus, 20 minutes a day for 3 days continuously, and training began from the 4th day. In the training group, the rats were trained with the combination of light and electricity. Each rat repeated for 60 times in each training, and the correct times were recorded, those correct for less than 25 times were taken as unqualified, and excluded from the training group, and supplemented by other rats in time. In the sham-training group, there was no fixed correlation between the application of light and electricity. The rats in the normal control group were given not any training. ③Detection of p

  11. First Insight into Exploration and Cognition in Wild Caught and Domesticated Sea Bass (Dicentrarchus labrax in a Maze.

    Directory of Open Access Journals (Sweden)

    David Benhaïm

    Full Text Available European sea bass aquaculture is so recent that very little is known on the effects of the early steps of its domestication. Behavioural parameters are sensitive indicators of the domestication process since they are generally impacted as soon as the first generation. The present work compared wild-caught and domesticated sea bass juvenile swimming activity, exploration and ability to learn to discriminate between two 2-D objects associated to a simple spatial task that enabled the tested individual to visually interact with an unfamiliar congener (the reward located behind a transparent wall at the end of one of the two arms of a maze. Ten fish from each origin were individually tested 3 times in a row during 3 days (9 trials in total. Fish were placed in a start box closed by a transparent wall located in front of two 2-D objects. Fish were filmed during 10 min after the removal of the start box wall. Different swimming variables including angular velocity, total distance travelled and velocity mean, were analyzed from videos as well as the time spent in each of 6 virtual zones including the reward zone near the congener (Cong and the zone opposite to the reward zone (OpCong. Two learning criteria were chosen: the number of successful turns and time to reach Cong. Behavioural differences were found between domesticated and wild fish. Angular velocity was higher in wild fish while the distance travelled and the velocity mean were higher in domesticated ones. Wild and domesticated fish spent most of the time in Cong and in OpCong. No differences were seen in learning ability between wild and domesticated fish. However, our findings for learning require confirmation by further studies with larger numbers of learning sessions and experiments designed to minimise stress. This study therefore demonstrated an impact of domestication on swimming behaviour but not on spatial learning.

  12. The beneficial effects of olibanum on memory deficit induced by hypothyroidism in adult rats tested in Morris water maze.

    Science.gov (United States)

    Hosseini, Mahmoud; Hadjzadeh, Mosa Al-Reza; Derakhshan, Mohammad; Havakhah, Shahrzad; Rassouli, Fatemeh Behnam; Rakhshandeh, Hassan; Saffarzadeh, Fatema

    2010-03-01

    Functional consequences of hypothyroidism include impaired learning and memory and inability to produce long-term potentiation (LTP) in hippocampus. Olibanum has been used for variety of therapeutic purposes. In traditional medicine, oilbanum is used to enhance learning and memory. In the present study the effect of olibanum on memory deficit in hypothyroid rats was investigated. Male wistar rats were divided into four groups and treated for 180 days. Group 1 received tap drinking water while in group 2, 0.03% methimazol was added to drinking water. Group 3 and 4 were treated with 0.03% methimazole as well as 100 and 500 mg/kg olibanum respectively. The animals were tested in Morris water maze. The swimming speed was significantly lower and the distance and time latency were higher in group 2 compared with group 1. In groups 3 and 4 the swimming speed was significantly higher while, the length of the swim path and time latency were significantly lower in comparison with group 2. It is concluded that methimazole-induced hypothyroidism impairs learning and memory in adult rats which could be prevented by using olibanum.

  13. Western Diet Chow Consumption in Rats Induces Striatal Neuronal Activation While Reducing Dopamine Levels without Affecting Spatial Memory in the Radial Arm Maze

    Science.gov (United States)

    Nguyen, Jason C. D.; Ali, Saher F.; Kosari, Sepideh; Woodman, Owen L.; Spencer, Sarah J.; Killcross, A. Simon; Jenkins, Trisha A.

    2017-01-01

    Rats fed high fat diets have been shown to be impaired in hippocampal-dependent behavioral tasks, such as spatial recognition in the Y-maze and reference memory in the Morris water maze (MWM). It is clear from previous studies, however, that motivation and reward factor into the memory deficits associated with obesity and high-fat diet consumption, and that the prefrontal cortex and striatum and neurotransmitter dopamine play important roles in cognitive performance. In this series of studies we extend our research to investigate the effect of a high fat diet on striatal neurochemistry and performance in the delayed spatial win-shift radial arm maze task, a paradigm highly reliant on dopamine-rich brain regions, such as the striatum after high fat diet consumption. Memory performance, neuronal activation and brain dopaminergic levels were compared in rats fed a “Western” (21% fat, 0.15% cholesterol) chow diet compared to normal diet (6% fat, 0.15% cholesterol)-fed controls. Twelve weeks of dietary manipulation produced an increase in weight in western diet-fed rats, but did not affect learning and performance in the delayed spatial win-shift radial arm maze task. Concurrently, there was an observed decrease in dopamine levels in the striatum and a reduction of dopamine turnover in the hippocampus in western diet-fed rats. In a separate cohort of rats Fos levels were measured after rats had been placed in a novel arena and allowed to explore freely. In normal rats, this exposure to a unique environment did not affect neuronal activation. In contrast, rats fed a western diet were found to have significantly increased Fos expression in the striatum, but not prefrontal cortex or hippocampus. Our study demonstrates that while western diet consumption in rats produces weight gain and brain neuronal and neurotransmitter changes, it did not affect performance in the delayed spatial win-shift paradigm in the radial arm maze. We conclude that modeling the cognitive

  14. Self-organization of maze-like structures via guided wrinkling.

    Science.gov (United States)

    Bae, Hyung Jong; Bae, Sangwook; Yoon, Jinsik; Park, Cheolheon; Kim, Kibeom; Kwon, Sunghoon; Park, Wook

    2017-06-01

    Sophisticated three-dimensional (3D) structures found in nature are self-organized by bottom-up natural processes. To artificially construct these complex systems, various bottom-up fabrication methods, designed to transform 2D structures into 3D structures, have been developed as alternatives to conventional top-down lithography processes. We present a different self-organization approach, where we construct microstructures with periodic and ordered, but with random architecture, like mazes. For this purpose, we transformed planar surfaces using wrinkling to directly use randomly generated ridges as maze walls. Highly regular maze structures, consisting of several tessellations with customized designs, were fabricated by precisely controlling wrinkling with the ridge-guiding structure, analogous to the creases in origami. The method presented here could have widespread applications in various material systems with multiple length scales.

  15. Die MAZE-Operation zur Behandlung des chronischen Vorhofflimmerns im Langzeitverlauf: 3-Jahres-Ergebnisse

    Directory of Open Access Journals (Sweden)

    Aigner C

    2005-01-01

    Full Text Available Grundlagen: Die MAZE-Operation mittels Ablation mit Mikrowelle oder Radiofrequenz ist ein etabliertes Verfahren zur Behandlung des chronischen Vorhofflimmerns. Diese Studie untersucht die Langzeitergebnisse nach 36 Monaten. Methodik: Zwischen 2/2001 und 12/2002 wurden 42 Patienten (64,5 ± 2,2 Jahre; 21 Männer mit chronischem Vorhofflimmern 6 Monate und zusätzlicher teils kombinierter Klappenerkrankung mittels Mitralklappenersatz/-rekonstruktion ± Trikuspidalklappenrekonstruktion (n = 30, Aortenklappenersatz ± Trikuspidalklappenrekonstruktion (n = 6 und Mitralklappen- und Aortenklappenersatz/- rekonstruktion ± Trikuspidalklappenrekonstruktion (n = 6 und MAZE operiert. Die mittlere Dauer des Vorhofflimmerns lag bei 63 ± 29 Monaten (7–384 Monate. Bei der MAZE-Operation wurden, dem Cox-III-Konzept folgend, in beiden Vorhöfen lineare Läsionen mit Mikrowellen- bzw. Radiofrequenzablation gesetzt. Ergebnisse: Die MAZE-Operation führte zu 23 ± 2 Minuten zusätzlicher Aortenklemmzeit (total: 89 ± 3 Min.. Aufgrund eines SIRS war bei einem Patienten der Intensivaufenthalt verlängert. Bei den restlichen Patienten war die Intubationsdauer 18,3 ± 6,7 Stunden, der Intensivaufenthalt 1,7 ± 0,6 Tage. 52,3 % wurden mit Amiodaron behandelt, 64,3 % kardiovertiert. 23,8 % Patienten benötigten einen Schrittmacher wegen eines AV-Blocks bzw. eines Sick-Sinus-Syndroms. Nach 12 Monaten waren 80,8 % frei von Vorhofflimmern. Beim letzten Nachuntersuchungszeitpunkt (36 ± 8 Monate waren 78,6 % frei von Vorhofflimmern. Schlußfolgerungen: Die MAZE-Operation mittels Mikrowellen- bzw. Radiofrequenzablation, folgend dem Cox-III-MAZE-Konzept, erhöht das chirurgische Risiko nur gering. Die Freiheit von Vorhofflimmern ist nach 1 und 3 Jahren praktisch gleich. Es ist also auch langfristig möglich, Patienten mit chronischem Vorhofflimmern einen stabilen Sinusrhythmus zu gewährleisten.

  16. Differential effect of antipsychotics on place navigation of rats in the Morris water maze. A comparative study between novel and reference antipsychotics.

    Science.gov (United States)

    Skarsfeldt, T

    1996-03-01

    A group of novel neuroleptics (e.g. olanzapine, seroquel, sertindole and ziprasidone) and already marketed compounds (e.g. clozapine, haloperidol and risperidone) were tested for acute effect on spatial learning and memory in Morris' water maze task. Young rats were trained for 4 consecutive days (three trials/day) to find a platform situated beneath the water surface. Two compounds, sertindole and seroquel, were without effect on spatial performance, whereas clozapine impaired performance on the first 2 test days but showed no effect compared to the controls on the last 2 test days. Ziprasidone and olanzapine markedly impaired spatial memory without affecting motor function (measured by the swimming speed). Risperidone and haloperidol also impaired performance but in addition both compounds significantly lowered the swimming speed. The present study indicates that several of the compounds impair spatial learning in Morris water maze. This might be of clinical importance in the treatment of schizophrenics, as many of these patients already show severe cognitive deficits. Therefore, certain antipsychotics could worsen the preexisting memory deficits in schizophrenic patients and this aspect should be considered before antipsychotic treatment.

  17. Human hippocampal and parahippocampal theta during goal-directed spatial navigation predicts performance on a virtual Morris water maze.

    Science.gov (United States)

    Cornwell, Brian R; Johnson, Linda L; Holroyd, Tom; Carver, Frederick W; Grillon, Christian

    2008-06-04

    The hippocampus and parahippocampal cortices exhibit theta oscillations during spatial navigation in animals and humans, and in the former are thought to mediate spatial memory formation. Functional specificity of human hippocampal theta, however, is unclear. Neuromagnetic activity was recorded with a whole-head 275-channel magnetoencephalographic (MEG) system as healthy participants navigated to a hidden platform in a virtual reality Morris water maze. MEG data were analyzed for underlying oscillatory sources in the 4-8 Hz band using a spatial filtering technique (i.e., synthetic aperture magnetometry). Source analyses revealed greater theta activity in the left anterior hippocampus and parahippocampal cortices during goal-directed navigation relative to aimless movements in a sensorimotor control condition. Additional analyses showed that left anterior hippocampal activity was predominantly observed during the first one-half of training, pointing to a role for this region in early learning. Moreover, posterior hippocampal theta was highly correlated with navigation performance, with the former accounting for 76% of the variance of the latter. Our findings suggest human spatial learning is dependent on hippocampal and parahippocampal theta oscillations, extending to humans a significant body of research demonstrating such a pivotal role for hippocampal theta in animal navigation.

  18. Effect of voluntary physical exercise and post-training epinephrine on acquisition of a spatial task in the barnes maze.

    Science.gov (United States)

    Jacotte-Simancas, Alejandra; Costa-Miserachs, David; Torras-Garcia, Meritxell; Coll-Andreu, Margalida; Portell-Cortés, Isabel

    2013-06-15

    A number of experiments have shown that physical exercise improves acquisition and retention for a variety of learning tasks in rodents. Most of these works have been conducted with tasks associated with a considerable level of stress, physical effort and/or food deprivation that might interact with exercise, thus hindering the interpretation of the results. On the other hand, it is well established that post-training epinephrine is able to facilitate memory consolidation, but only a few works have studied its effect on the process of acquisition. The present work was aimed at studying whether 17 days of voluntary physical exercise (running wheels) and/or post-training epinephrine (0.01 or 0.05 mg/kg) could improve the acquisition of a spatial task in the Barnes maze, and whether the combination of the two treatments have additive effects. Our results showed that exercise improved acquisition, and 0.01 mg/kg of epinephrine tended to enhance it, by reducing the distance needed to find the escape hole. The combination of both treatments failed to further improve the acquisition level. We concluded that both treatments exerted their effect on acquisition by enhancing the process of learning itself, and that exercise is able to improve acquisition even using tasks with a low level of stress and physical effort.

  19. Water maze performance and changes in serum corticosterone levels in zinc-deprived and pair-fed rats.

    Science.gov (United States)

    Chu, Y; Mouat, M F; Harris, R B S; Coffield, J A; Grider, A

    2003-04-01

    The aims of the present study were (1) to evaluate the learning and short- and long-term memory of zinc-deprived (ZD) and pair-fed (PF) rats in a Morris water maze (MWM) and (2) to monitor the serum corticosterone levels of these rats before and after swimming. Young Sprague-Dawley rats (aged 27-31 days) consumed AIN-93G diet for 10 days, and then were separated into ad libitum control (CT), PF and ZD groups. The zinc content of the diet was 25-30 ppm (CT and PF) or preference for the target zone in the first 15 s of the probing test. When the total 120 s of the probing test was considered, there were no differences in preference for the target zone, but thigmotaxia was greater in the PF than the CT group. The only behavioral change of the ZD group was thigmotaxia observed during the 120-s probing test following training, indicating the increment of anxiety. Morning basal corticosterone levels before swim training were significantly elevated in the PF group on Day 15 of dietary treatment, whereas a significant elevation of the basal corticosterone level in the ZD group was not statistically significant until Day 22. The data indicate an association between impaired learning, poor searching strategy and elevated corticosterone in the PF group. In contrast, the ZD rats showed normal cognitive performance but had elevated corticosterone and increased anxiety-like behavior (thigmotaxia).

  20. Reading Assessment Methods for Middle-School Students: An Investigation of Reading Comprehension Rate and Maze Accurate Response Rate

    Science.gov (United States)

    Hale, Andrea D.; Henning, Jaime B.; Hawkins, Renee O.; Sheeley, Wesley; Shoemaker, Larissa; Reynolds, Jennifer R.; Moch, Christina

    2011-01-01

    This study was designed to investigate the validity of four different aloud reading comprehension assessment measures: Maze, comprehension questions, Maze accurate response rate (MARR), and reading comprehension rate (RCR). The criterion measures used in this study were the Woodcock-Johnson III Tests of Achievement (WJ-III ACH) Broad Reading…

  1. A robust animal model of state anxiety : fear-potentiated behaviour in the elevated plus-maze

    NARCIS (Netherlands)

    Korte, SM; De Boer, SF

    2003-01-01

    Fear (i.e., decreased percentage time spent on open-arm exploration) in the elevated plus-maze can be potentiated by prior inescapable stressor exposure, but not by escapable stress. The use of fear-potentiated plus-maze behaviour has several advantages as compared to more traditional animal models

  2. A randomized study of combining maze surgery for atrial fibrillation with mitral valve surgery

    NARCIS (Netherlands)

    Jessurun, ER; Van Hemel, NM; Defauw, JJ; De La Riviere, AB; Stofmeel, MAM; Kingma, JH; Ernst, JMPG

    Aim Mitral valve surgery seldom suppresses atrial fibrillation (AF), present prior to surgery. Maze III surgery eliminates AF in >80% of cases, the reason why combining this procedure with mitral valve surgery in patients with AF seems worthwhile. We prospectively studied the outcome of combining

  3. Anxiolytic effect of clonazepam in female rats: grooming microstructure and elevated plus maze tests.

    Science.gov (United States)

    Nin, Maurício S; Couto-Pereira, Natividade S; Souza, Marilise F; Azeredo, Lucas A; Ferri, Marcelo K; Dalprá, Walesca L; Gomez, Rosane; Barros, Helena M T

    2012-06-01

    Grooming behavior is an adaptation to a stressful environment that can vary in accordance with stress intensity. Direct and indirect GABA(A) receptor agonists decrease duration, frequency, incorrect transitions and uninterrupted bouts of grooming. Hormonal variation during the different phases of the estrous cycle of female rats also changes the grooming behavior. It is known that GABA(A) agonists and endogenous hormones change anxiety-like behaviors observed in the elevated plus maze test, a classical animal model of anxiety. This study was designed to determine the anxiolytic effect of clonazepam in female rats in different estrous phases and to correlate anxiety behaviors in the elevated plus maze and grooming microstructure tests. Our results show that female rats displayed higher anxiety-like behavior scores during the estrus and proestrus phases in the elevated plus maze and that clonazepam (0.25 mg/kg; i.p.) had an anxiolytic effect that was independent of the estrous phase. Grooming behaviors were higher in the proestrus phase but were decreased by clonazepam administration, independent of the estrous phase, demonstrating the anxiolytic effect of this drug in both animal models. Grooming behaviors were moderately associated with anxiolytic-like behaviors in the elevated plus maze test. Here, we describe the anxiolytic effect of clonazepam and the influence of estrous phase on anxiety. Moreover, we show that the grooming microstructure test is a useful tool for detecting anxiolytic-like behaviors in rats.

  4. Sinus node function after cardiac surgery : is impairment specific for the maze procedure?

    NARCIS (Netherlands)

    Tuinenburg, AE; Van Gelder, IC; Van Den Berg, MP; Grandjean, JG; Tieleman, RG; Smit, AJ; Huet, RCG; Van Der Maaten, JMAA; Volkers, CP; Ebels, T; Crijns, HJGM

    2004-01-01

    Background: Maze surgery is a final solution for intractable atrial fibrillation (AF), but an adverse effect on postoperative sinus node function has been reported. Whether this also applies to other types of cardiac surgery is unclear. Methods: We assessed postoperative rhythm by means of repeated

  5. Surgical Radiofrequency MAZE III Ablation for Treatment of Atrial Fibrillation During Open Heart Surgery

    Directory of Open Access Journals (Sweden)

    Fariborz Akbarzadeh

    2006-05-01

    Full Text Available Background: Atrial fibrillation is a common arrhythmia in patients with rheumatic mitral and other valve diseases who are candidates for valve repair surgeries. Conversion of rhythm to sinus has positive effects on quality of life and lower use of medications. The aim of this clinical study was to evaluate the effectiveness of the radiofrequency ablation Maze III procedure in the treatment of atrial fibrillation associated with rheumatic heart valve disease. Methods: We applied a modified Cox III Maze procedure using radiofrequency ablation in the treatment of atrial fibrillation associated with rheumatic heart valve disease and evaluated the outcome of 20 patients of atrial fibrillation associated rheumatic valve disease who underwent radiofrequency ablation Maze III procedure plus heart valve surgery. Demographic, echocardiographic, Electrocardiographic and Doppler study data were calculated before surgery, six month and one year after surgery.. Results: No perioperative deaths occurred in the study group. Duration of additional time for doing radiofrequency ablation was about 22 minutes. Freedom from atrial fibrillation was 85% and 75% at six months and one year follow-up respectively... Conclusions: The addition of the radiofrequency ablation Maze procedure to heart valve surgery is safe and effective in the treatment of atrial fibrillation associated with rheumatic heart valve disease.

  6. Incremental Sentence Processing in Japanese: A Maze Investigation into Scrambled and Control Sentences

    Science.gov (United States)

    Witzel, Jeffrey; Witzel, Naoko

    2016-01-01

    This study investigates preverbal structural and semantic processing in Japanese, a head-final language, using the maze task. Two sentence types were tested--simple scrambled sentences (Experiment 1) and control sentences (Experiment 2). Experiment 1 showed that even for simple, mono-clausal Japanese sentences, (1) there are online processing…

  7. Just add water: cannabinoid discrimination in a water T-maze with FAAH(-/-) and FAAH(+/+) mice.

    Science.gov (United States)

    Wiley, Jenny L; Lefever, Timothy W; Pulley, Nikita S; Marusich, Julie A; Cravatt, Benjamin F; Lichtman, Aron H

    2016-08-01

    Incomplete overlap in the discriminative stimulus effects of Δ-tetrahydrocannabinol (THC) and the endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol has been reported in food-reinforced tasks. The aim of this study was to examine cannabinoid discriminative stimulus effects in a nonappetitive procedure. Adult male mice lacking the gene for AEA's major metabolic enzyme, fatty acid amide hydrolase (FAAH), and FAAH mice were trained to discriminate THC or AEA in a water T-maze, in which the response was swimming to an escape platform on the injection-appropriate side. JZL184, a monoacylglycerol lipase inhibitor, was also tested. FAAH mice showed faster acquisition than FAAH mice. THC and AEA fully substituted, with only minor cross-procedure potency variations. Incomplete substitution of JZL184 was observed in THC-trained FAAH mice in the water-maze task, as contrasted with full substitution in a food-reinforced nose-poke procedure. Stress-induced changes in AEA and/or 2-arachidonoylglycerol concentrations in the brain may have mediated this attenuation. JZL184 also partially substituted in AEA-trained FAAH mice in the water maze, suggesting incomplete overlap in the stimulus effects of AEA and JZL184. Through the use of a novel water-maze procedure, the present study supports the work of previous behavioral pharmacologists in showing the robustness of the discrimination paradigm.

  8. Incremental Sentence Processing in Japanese: A Maze Investigation into Scrambled and Control Sentences

    Science.gov (United States)

    Witzel, Jeffrey; Witzel, Naoko

    2016-01-01

    This study investigates preverbal structural and semantic processing in Japanese, a head-final language, using the maze task. Two sentence types were tested--simple scrambled sentences (Experiment 1) and control sentences (Experiment 2). Experiment 1 showed that even for simple, mono-clausal Japanese sentences, (1) there are online processing…

  9. A randomized study of combining maze surgery for atrial fibrillation with mitral valve surgery

    NARCIS (Netherlands)

    Jessurun, ER; Van Hemel, NM; Defauw, JJ; De La Riviere, AB; Stofmeel, MAM; Kingma, JH; Ernst, JMPG

    2003-01-01

    Aim Mitral valve surgery seldom suppresses atrial fibrillation (AF), present prior to surgery. Maze III surgery eliminates AF in >80% of cases, the reason why combining this procedure with mitral valve surgery in patients with AF seems worthwhile. We prospectively studied the outcome of combining th

  10. Effect of a water-maze procedure on the redox mechanisms in brain parts of aged rats.

    Science.gov (United States)

    Krivova, Natalia A; Zaeva, Olga B; Grigorieva, Valery A

    2015-01-01

    The Morris water maze (MWM) is a tool for assessment of age-related modulations spatial learning and memory in laboratory rats. In our work was investigated the age-related decline of MWM performance in 11-month-old rats and the effect exerted by training in the MWM on the redox mechanisms in rat brain parts. Young adult (3-month-old) and aged (11-month-old) male rats were trained in the MWM. Intact animals of the corresponding age were used as the reference groups. The level of pro- and antioxidant capacity in brain tissue homogenates was assessed using the chemiluminescence method. A reduced performance in the MWM test was found in 11-month-old rats: at the first day of training they showed only 30% of successful MWM trials. However, at the last training day the percentage of successful trials was equal for young adult and aged animals. This indicates that the aged 11-month-old rats can successfully learn in MWM. Therewith, the MWM spatial learning procedure itself produces changes in different processes of redox homeostasis in 11-month-old and 3-month-old rats as compared to intact animals. Young adult rats showed a decrease in prooxidant capacity in all brain parts, while 11-month-old rats demonstrated an increase in antioxidant capacity in the olfactory bulb, pons + medulla oblongata and frontal lobe cortex. Hence, the MWM procedure activates the mechanisms that restrict the oxidative stress in brain parts. The obtained results may be an argument for further development of the animal training procedures aimed to activate the mechanisms that can prevent the age-related deterioration of performance in the learning test. This may be useful not only for the development of training procedures applicable to human patients with age-related cognitive impairments, but also for their rehabilitation.

  11. Are benzodiazepines really anxiolytic? Evidence from a 3D maze spatial navigation task.

    Science.gov (United States)

    Ennaceur, A; Michalikova, S; van Rensburg, R; Chazot, P L

    2008-03-17

    The effects of diazepam and chlordiazepoxide were assessed in a 3D maze which is a modification of an 8-arm radial maze. Each arm of the maze is attached to a bridge radiating from a central platform. Animals exposed for the first time to the maze do not venture beyond the line that separate a bridge from an arm. The prime criteria set for an anxiolytic effect is whether mice would increase the frequency of entries onto arms and increase arm/bridge entries ratio. C57 mice readily cross the line on first exposure and make more than 8 arm visits onto arms on second exposure, while other strains (CD-1 and Balb/c) hold back and rarely cross the line on first exposure and require more sessions to make more than 8 arm entries. An anxiolytic drug is expected to encourage intermediate (CD-1) and high (Balb/c) anxiety mice to adventure onto the arms of the maze and make more visits to the arms to comparable levels seen with low anxiety c57 mice. In the present report, administration of different doses of diazepam (0.625, 1.25, 2.5 and 5 mg kg(-1) i.p.) and chlordiazepoxide (5, 10 and 15 mg kg(-1) i.p.) did not reduce anxiety in animals, with the lowest dose of diazepam increasing motor activity in Balb/c and increasing anxiety in c57 mice while the highest doses of both diazepam (2.5 and 5 mg kg(-1) i.p.) and chlordiazepoxide (15 mg kg(-1) i.p.) induced mild sedation. Our results raise some concerns about the methodological foundations in the current assessment of anxiety and anxiolytic compounds both in animal and human studies.

  12. Neonatal handling affects learning, reversal learning and antioxidant enzymes activities in a sex-specific manner in rats.

    Science.gov (United States)

    Noschang, Cristie; Krolow, Rachel; Arcego, Danusa Mar; Toniazzo, Ana Paula; Huffell, Ana Paula; Dalmaz, Carla

    2012-06-01

    Early life experiences have profound influences on behavior and neurochemical parameters in adult life. The aim of this study is to verify neonatal handling-induced sex specific differences on learning and reversal learning as well as oxidative stress parameters in the prefrontal cortex and striatum of adult rats. Litters of rats were non-handled or handled (10 min/day, days 1-10 after birth). In adulthood, learning and reversal learning were evaluated using a Y maze associated with palatable food in male and female rats. Morris water maze reversal learning was verified in males. Oxidative stress parameters were evaluated in both genders. Male neonatal handled animals had a worse performance in the Y maze reversal learning compared to non-handled ones and no difference was observed in the water maze reversal learning task. Regarding females, neonatal handled rats had a better performance during the Y maze learning phase compared to non-handled ones. In addition, neonatal handled female animals showed a decreased SOD/CAT ratio in the PFC compared to non-handled females. We conclude that neonatal handling effects on learning and memory in adult rats are sex and task specific. The sex specific differences are also observed in the evaluation of antioxidant enzymes activities with neonatal handling affecting only females. Copyright © 2012 ISDN. Published by Elsevier Ltd. All rights reserved.

  13. The effect of a paraffin screen on the neutron dose at the maze door of a 15 MV linear accelerator.

    Science.gov (United States)

    Krmar, M; Nikolić, D; Kuzmanović, A; Kuzmanović, Z; Ganezer, K

    2013-08-01

    The purpose of this study was to explore the effects of a paraffin screen located at various positions in the maze on the neutron dose equivalent at the maze door. The neutron dose equivalent was measured at the maze door of a room containing a 15 MV linear accelerator for x-ray therapy. Measurements were performed for several positions of the paraffin screen covering only 27.5% of the cross-sectional area of the maze. The neutron dose equivalent was also measured at all screen positions. Two simple models of the neutron source were considered in which the first assumed that the source was the cross-sectional area at the inner entrance of the maze, radiating neutrons in an isotropic manner. In the second model the reduction in the neutron dose equivalent at the maze door due to the paraffin screen was considered to be a function of the mean values of the neutron fluence and energy at the screen. The results of this study indicate that the equivalent dose at the maze door was reduced by a factor of 3 through the use of a paraffin screen that was placed inside the maze. It was also determined that the contributions to the dosage from areas that were not covered by the paraffin screen as viewed from the dosimeter, were 2.5 times higher than the contributions from the covered areas. This study also concluded that the contributions of the maze walls, ceiling, and floor to the total neutron dose equivalent were an order of magnitude lower than those from the surface at the far end of the maze. This study demonstrated that a paraffin screen could be used to reduce the neutron dose equivalent at the maze door by a factor of 3. This paper also found that the reduction of the neutron dose equivalent was a linear function of the area covered by the maze screen and that the decrease in the dose at the maze door could be modeled as an exponential function of the product φ·E at the screen.

  14. The effect of a paraffin screen on the neutron dose at the maze door of a 15 MV linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Krmar, M.; Kuzmanović, A. [Physics Department, Faculty of Science, University of Novi Sad, Novi Sad 21000 (Serbia); Nikolić, D. [National Institute for Nanotechnology, Edmonton, Alberta T6G 2M9 (Canada); Kuzmanović, Z. [International Medical Centers, Banja Luka 78000, Republika Srpska, Bosnia and Herzegovina (Bosnia and Herzegowina); Ganezer, K. [Physics Department, California State University Dominguez Hills, Carson, California 90747 (United States)

    2013-08-15

    Purpose: The purpose of this study was to explore the effects of a paraffin screen located at various positions in the maze on the neutron dose equivalent at the maze door.Methods: The neutron dose equivalent was measured at the maze door of a room containing a 15 MV linear accelerator for x-ray therapy. Measurements were performed for several positions of the paraffin screen covering only 27.5% of the cross-sectional area of the maze. The neutron dose equivalent was also measured at all screen positions. Two simple models of the neutron source were considered in which the first assumed that the source was the cross-sectional area at the inner entrance of the maze, radiating neutrons in an isotropic manner. In the second model the reduction in the neutron dose equivalent at the maze door due to the paraffin screen was considered to be a function of the mean values of the neutron fluence and energy at the screen.Results: The results of this study indicate that the equivalent dose at the maze door was reduced by a factor of 3 through the use of a paraffin screen that was placed inside the maze. It was also determined that the contributions to the dosage from areas that were not covered by the paraffin screen as viewed from the dosimeter, were 2.5 times higher than the contributions from the covered areas. This study also concluded that the contributions of the maze walls, ceiling, and floor to the total neutron dose equivalent were an order of magnitude lower than those from the surface at the far end of the maze.Conclusions: This study demonstrated that a paraffin screen could be used to reduce the neutron dose equivalent at the maze door by a factor of 3. This paper also found that the reduction of the neutron dose equivalent was a linear function of the area covered by the maze screen and that the decrease in the dose at the maze door could be modeled as an exponential function of the product φ·E at the screen.

  15. The influence of antidotal treatment of low-level tabun exposure on cognitive functions in rats using a water maze.

    Science.gov (United States)

    Kassa, J; Kunesova, G

    2006-01-01

    In this study, the influence of antidotal treatment of tabun poisoning on cognitive function, in the case of low-level tabun exposure, was studied. The impairment of cognitive function was evaluated by the measurement of spatial learning and memory in rats poisoned with a sublethal dose of tabun and treated with atropine alone or in combination with newly developed oximes {K027 [1-(4-hydroxyiminomethyl- pyridinium)-3-(4-carbamoylpyridinium) propane dibromide] and K048 [1-(4-hydroxyimino- methylpyridinium)-3-(4-carbamoylpyridinium) butane dibromide]} or currently available oxime (trimedoxime), using the Morris water maze. While atropine alone caused an impairment of studied cognitive functions, the addition of an oxime to atropine contributes to the improvement of cognitive performance of treated tabun-poisoned rats regardless of the type of oxime. The differences in the ameliorative effects of oximes on atropine-induced mnemonic deficits were not significant. Therefore, each low-level nerve agent exposure should be treated by complex antidotal treatment consisting of anticholinergic drug and oxime.

  16. A Preliminary Study of Functional Brain Activation among Marijuana Users during Performance of a Virtual Water Maze Task

    Directory of Open Access Journals (Sweden)

    Jennifer Tropp Sneider

    2013-01-01

    Full Text Available Numerous studies have reported neurocognitive impairments associated with chronic marijuana use. Given that the hippocampus contains a high density of cannabinoid receptors, hippocampal-mediated cognitive functions, including visuospatial memory, may have increased vulnerability to chronic marijuana use. Thus, the current study examined brain activation during the performance of a virtual analogue of the classic Morris water maze task in 10 chronic marijuana (MJ users compared to 18 nonusing (NU comparison subjects. Imaging data were acquired using blood oxygen level-dependent (BOLD functional MRI at 3.0 Tesla during retrieval (hidden platform and motor control (visible platform conditions. While task performance on learning trials was similar between groups, MJ users demonstrated a deficit in memory retrieval. For BOLD fMRI data, NU subjects exhibited greater activation in the right parahippocampal gyrus and cingulate gyrus compared to the MJ group for the Retrieval-Motor Control contrast (NU > MJ. These findings suggest that hypoactivation in MJ users may be due to differences in the efficient utilization of neuronal resources during the retrieval of memory. Given the paucity of data on visuospatial memory function in MJ users, these findings may help elucidate the neurobiological effects of marijuana on brain activation during memory retrieval.

  17. Influence of spatial environment on maze learning in an African mole-rat

    CSIR Research Space (South Africa)

    Du Toit, L

    2012-05-01

    Full Text Available of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, Wits 2050, South Africa e-mail: martin.whiting@mq.edu.au Present Address: L. du Toit, Obesity Research and Management, University of Alberta...

  18. Modified radial v/s biatrial maze for atrial fibrillation in rheumatic valvular heart surgery

    Science.gov (United States)

    Sayed, Sajid A.; Katewa, Ashish; Srivastava, Vivek; Jana, Sujit; Patwardhan, Anil M.

    2014-01-01

    Background Atrial fibrillation (AF) is commonest sustained atrial arrhythmia producing high morbidity. Although Cox's Maze III procedure cures AF in majority, reduced atrial transport function (ATF) is a concern. Radial approach with ablation lines radial from sinus node towards atrioventricular annulii and parallel to atrial coronary arteries, has shown better ATF. Methods Single blind open randomized prospective study of 80 patients was undertaken in two groups (40 each) of modified Cox's maze III and modified radial approach, to evaluate conversion to normal sinus rhythm (NSR) and ATF. Patients undergoing surgery for rheumatic valvular heart disease with continuous AF were prospectively randomized. Ablation lines were created with radiofrequency (RF) bipolar coagulation with cryoablation for the isthmal lesions and coronary sinus. Results were compared at 6 months and ATF was evaluated by atrial filling fraction (AFF) and A/E ratio on echocardiography. Results The rate of conversion to NSR in both groups was statistically insignificant by Fisher's exact test (p > 0.05). ATF was better in modified radial approach compared to modified Cox's Maze III (A/E compared by unpaired t test:0.52 ± 0.08 v/s 0.36 ± 0.10; p < 0.05. AFF compared using Mann Whitney U test: median AFF for radial group was 23 v/s 20 for biatrial group; p < 0.05). Discussion In patients with AF undergoing rheumatic valvular surgery, radiofrequency radial approach is as effective as modified Cox's maze III for conversion to NSR with better atrial transport function. PMID:25443604

  19. Anxiolytic-induced attenuation of thigmotaxis in the Elevated Minus Maze.

    Science.gov (United States)

    Pickles, A R; Hendrie, C A

    2013-07-01

    Findings using exploration models of anxiety such as the Elevated Plus Maze (EPM) and Elevated Zero Maze (EZM) are remarkably consistent given the differences in layout and number of walls used to describe their closed areas. These factors therefore do not appear to be critical. The present studies were conducted to determine if anxiolytic activity could be detected using an apparatus that presented animals with only one wall. Mice were pre-treated with either vehicle, diazepam (2-4 mg/kg) or 5-10 mg/kg chlordiazepoxide (CDP) and placed for 5 min onto a square platform containing a 12 cm × 14 cm wall. Measures were taken of frequency/duration of contacts with the wall and of general activity. Time spent in contact with the wall was selectively reduced by 4 mg/kg diazepam. 10 mg/kg CDP also decreased this measure but increased measures of general activity, indicating a possible mild stimulant effect. The closed areas of the EPM are described by 3 walls. The EZM uses 2. Current findings show that anxiolytic effects can also be detected in a model with just one wall. It could and these data provide further evidence that variations in the layout of these mazes are not critical for detecting anxiolytic action. Thigmotactic cues remain present regardless of the physical characteristics of these mazes or the local conditions they are employed under. Hence, it is suggested that thigmotactic cues may be the common source of motivation to behave in these models and that this may explain their robustness.

  20. Search Strategies Used by "APP" Transgenic Mice during Navigation in the Morris Water Maze

    Science.gov (United States)

    Janus, Christopher

    2004-01-01

    TgCRND8 mice represent a transgenic mouse model of Alzheimer's disease, with onset of cognitive impairment and increasing amyloid-[beta] plaques in their brains at 12 weeks of age. In this study, the spatial memory in 25- to 30-week-old TgCRND8 mice was analyzed in two reference and one working memory Morris water maze (MWM) tests. In reference…

  1. Comparisons of Online Reading Paradigms: Eye Tracking, Moving-Window, and Maze

    Science.gov (United States)

    Witzel, Naoko; Witzel, Jeffrey; Forster, Kenneth

    2012-01-01

    This study compares four methodologies used to examine online sentence processing during reading. Specifically, self-paced, non-cumulative, moving-window reading (Just et al. in "J Exp Psychol Gen" 111:228-238, 1982), eye tracking (see e.g., Rayner in "Q J Exp Psychol" 62:1457-1506, 2009), and two versions of the maze task (Forster et al. in…

  2. Comparisons of Online Reading Paradigms: Eye Tracking, Moving-Window, and Maze

    Science.gov (United States)

    Witzel, Naoko; Witzel, Jeffrey; Forster, Kenneth

    2012-01-01

    This study compares four methodologies used to examine online sentence processing during reading. Specifically, self-paced, non-cumulative, moving-window reading (Just et al. in "J Exp Psychol Gen" 111:228-238, 1982), eye tracking (see e.g., Rayner in "Q J Exp Psychol" 62:1457-1506, 2009), and two versions of the maze task (Forster et al. in…

  3. Neutron dose calculation at the maze entrance of medical linear accelerator rooms.

    Science.gov (United States)

    Falcão, R C; Facure, A; Silva, A X

    2007-01-01

    Currently, teletherapy machines of cobalt and caesium are being replaced by linear accelerators. The maximum photon energy in these machines can vary from 4 to 25 MeV, and one of the great advantages of these equipments is that they do not have a radioactive source incorporated. High-energy (E > 10 MV) medical linear accelerators offer several physical advantages over lower energy ones: the skin dose is lower, the beam is more penetrating, and the scattered dose to tissues outside the target volume is smaller. Nevertheless, the contamination of undesirable neutrons in the therapeutic beam, generated by the high-energy photons, has become an additional problem as long as patient protection and occupational doses are concerned. The treatment room walls are shielded to attenuate the primary and secondary X-ray fluence, and this shielding is generally adequate to attenuate the neutrons. However, these neutrons are scattered through the treatment room maze and may result in a radiological problem at the door entrance, a high occupancy area in a radiotherapy facility. In this article, we used MCNP Monte Carlo simulation to calculate neutron doses in the maze of radiotherapy rooms and we suggest an alternative method to the Kersey semi-empirical model of neutron dose calculation at the entrance of mazes. It was found that this new method fits better measured values found in literature, as well as our Monte Carlo simulated ones.

  4. T-maze performance after developmental exposure to 19F tagged 5-HTP in chicks.

    Science.gov (United States)

    Dingman, Sherry; Nash, Laurie; Hogan, Jeremy; Branch, Craig

    2004-12-01

    Chicks were used as a model to investigate behavioral effects of administering a new compound intended for use with magnetic resonance. The compound has multiple 19F atom tags covalently bonded to the indole ring of 5-hydroxytryptophan (PF-5HTP), the immediate precursor to the neurotransmitter serotonin. On incubation Day 17, 5 microg of PF-5-HTP, an equivalent amount of 5-HTP, or just 200 microL of the weak phosphate buffered saline (PBS) vehicle was injected into the airsac of each egg. Three days after hatching, chicks were isolated at the top of a simple T-Maze which, when traversed correctly, enabled them to return to their brood mates. A second trial in the T-Maze was conducted about three hours later. The brief period of isolation at the start of a trial causes social distress in chicks who are reinforced by returning to the brood. The task was selected as being sensitive to functioning of the serotonin pathways whose development might be altered by administering the compound during brain development. Repeated-measures analysis of variance yielded a statistically significant main effect for trial within groups, but no significant difference between injection groups. Administering a low dose of the fluorine tagged compound during development did not impair performance on this T-maze task.

  5. Aerobic fitness relates to learning on a virtual morris water task and hippocampal volume in adolescents

    OpenAIRE

    Herting, Megan M.; Nagel, Bonnie J

    2012-01-01

    In rodents, exercise increases hippocampal neurogenesis and allows for better learning and memory performance on water maze tasks. While exercise has also been shown to be beneficial for the brain and behavior in humans, no study has examined how exercise impacts spatial learning using a directly translational water maze task, or if these relationships exist during adolescence – a developmental period which the animal literature has shown to be especially vulnerable to exercise effects. In th...

  6. Maze Surgery

    Science.gov (United States)

    ... called chronic atrial fibrillation (AF). AF is a fast, irregular heart rhythm where the upper chambers of the heart contract in an uncoordinated fashion. AF is dangerous because it may cause blood ...

  7. Non-acute effects of different doses of 3, 4-methylenedioxymethamphetamine on spatial memory in the Morris water maze in Sprague-Dawley male rats

    Institute of Scientific and Technical Information of China (English)

    Sara Soleimani Asl; Mohammad Hassan Farhadi; Nasser Naghdi; Samira Choopani; Alireza Samzadeh-Kermani; Mehdi Mehdizadeh

    2011-01-01

    3, 4-methylenedioxymethamphetamine (MDMA; also known as 'ecstasy') has been shown to impair learning and spatial memory in adult and neonatal rats.Many studies have focused on the acute effects of MDMA on memory.In the present study, we intraperitoneally administered MDMA (0, 5, 10, 20 mg/kg) to adult male rats to investigate the effects of different doses on rat spatial memory in the Morris water maze, body temperature, and mortality, twice a day, for 7 successive days.The results indicated that MDMA impaired spatial memory dose-dependently, with the highest dose (20 mg/kg) exerting the strongest effects.In addition, MDMA also caused hyperthermia and increased mortality in rats.

  8. Mouse hippocampal GABAB1 but not GABAB2 subunit-containing receptor complex levels are paralleling retrieval in the multiple-T-maze

    Directory of Open Access Journals (Sweden)

    Soheil eKeihan Falsafi

    2015-10-01

    Full Text Available GABAB receptors are heterodimeric G-protein coupled receptors known to be involved in learning and memory. Although a role for GABAB receptors in cognitive processes is evident, there is no information on hippocampal GABAB receptor complexes in a multiple T maze (MTM task, a robust paradigm for evaluation of spatial learning.Trained or untrained (yoked control C57BL/6J male mice (n=10/group were subjected to the MTM task and sacrificed 6 hours following their performance. Hippocampi were taken, membrane proteins extracted and run on blue native PAGE followed by immunoblotting with specific antibodies against GABAB1, GABAB1a and GABAB2. Immunoprecipitation with subsequent mass spectrometric identification of co-precipitates was carried out to show if GABAB1 and GABAB2 as well as other interacting proteins co-precipitate. An antibody shift assay (ASA and a proximity ligation assay (PLA were also used to see if the two GABAB subunits are present in the receptor complex.Single bands were observed on Western blots, each representing GABAB1, GABAB1a or GABAB2 at an apparent molecular weight of approximately 100 kDa. Subsequently, densitometric analysis revealed that levels of GABAB1 and GABAB1a but not GABAB2- containing receptor complexes were significantly higher in trained than untrained groups. Immunoprecipitation followed by mass spectrometric studies confirmed the presence of GABAB1, GABAB2, calcium calmodulin kinases I and II, GluA1 and GluA2 as constituents of the complex. ASA and PLA also showed the presence of the two subunits of GABAB receptor within the complex. It is shown that increased levels of GABAB1 subunit-containing complexes are paralleling performance in a land maze.

  9. Navigating to new frontiers in behavioral neuroscience: Traditional neuropsychological tests predict human performance on a rodent-inspired radial-arm maze

    Directory of Open Access Journals (Sweden)

    Sarah E. Mennenga

    2014-09-01

    Full Text Available We constructed an 11-arm, walk-through, human radial-arm maze (HRAM as a translational instrument to compare existing methodology in the areas of rodent and human learning and memory research. The HRAM, utilized here, serves as an intermediary test between the classic rat radial-arm maze (RAM and standard human neuropsychological and cognitive tests. We show that the HRAM is a useful instrument to examine working memory ability, explore the relationships between rodent and human memory and cognition models, and evaluate factors that contribute to human navigational ability. One-hundred-and-fifty-seven participants were tested on the HRAM, and scores were compared to performance on a standard cognitive battery focused on episodic memory, working memory capacity, and visuospatial ability. We found that errors on the HRAM increased as working memory demand became elevated, similar to the pattern typically seen in rodents, and that for this task, performance appears similar to Miller’s classic description of human working memory capacity of 7±2 items. Regression analysis revealed that measures of working memory capacity and visuospatial ability accounted for a large proportion of variance in HRAM scores, while measures of episodic memory and general intelligence did not serve as significant predictors of HRAM performance. We present the HRAM as a novel instrument for measuring navigational behavior in humans, as is traditionally done in basic science studies evaluating rodent learning and memory, thus providing a useful tool to help connect and translate between human and rodent models of cognitive functioning.

  10. Hippocampal-dependent spatial memory in the water maze is preserved in an experimental model of temporal lobe epilepsy in rats.

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    Marion Inostroza

    Full Text Available Cognitive impairment is a major concern in temporal lobe epilepsy (TLE. While different experimental models have been used to characterize TLE-related cognitive deficits, little is known on whether a particular deficit is more associated with the underlying brain injuries than with the epileptic condition per se. Here, we look at the relationship between the pattern of brain damage and spatial memory deficits in two chronic models of TLE (lithium-pilocarpine, LIP and kainic acid, KA from two different rat strains (Wistar and Sprague-Dawley using the Morris water maze and the elevated plus maze in combination with MRI imaging and post-morten neuronal immunostaining. We found fundamental differences between LIP- and KA-treated epileptic rats regarding spatial memory deficits and anxiety. LIP-treated animals from both strains showed significant impairment in the acquisition and retention of spatial memory, and were unable to learn a cued version of the task. In contrast, KA-treated rats were differently affected. Sprague-Dawley KA-treated rats learned less efficiently than Wistar KA-treated animals, which performed similar to control rats in the acquisition and in a probe trial testing for spatial memory. Different anxiety levels and the extension of brain lesions affecting the hippocampus and the amydgala concur with spatial memory deficits observed in epileptic rats. Hence, our results suggest that hippocampal-dependent spatial memory is not necessarily affected in TLE and that comorbidity between spatial deficits and anxiety is more related with the underlying brain lesions than with the epileptic condition per se.

  11. Behavioral profiles displayed by rats in an elevated asymmetric plus-maze: effects of diazepam

    Directory of Open Access Journals (Sweden)

    Ruarte M.B.

    1999-01-01

    Full Text Available When rats are exposed to unknown environments where novelty and fear-inducing characteristics are present (conflictive environments, some specific behaviors are induced and exploration is apparently modulated by fear. In our laboratory, a new type of plus-maze was designed as a model of conflictive exploration. The maze is composed of four arms with different geometrical characteristics, differing from each other by the presence or absence of walls. The degree of asymmetry was as follows: NW, no wall arm; SW, a single high wall present; HL, a low and a high wall present, and HH, two high walls present. The four arms were arranged at 90o angles and the apparatus was called the elevated asymmetric plus-maze (APM. The purpose of the present study was to assess the behavioral profile of rats exposed for a single time to the APM with or without treatment with benzodiazepine. Increasing doses of diazepam were injected intraperitoneally in several groups of male, 90-day-old Holtzman rats. Distilled water was injected in control animals. Thirty minutes after treatment all rats were exposed singly to a 5-min test in the APM. Diazepam induced a biphasic modification of exploration in the NW and SW arms. The increase in the exploration score was evident at low doses of diazepam (0.25-1.0 mg/kg body weight and the decrease in exploration was found with the higher doses of diazepam (2.0-3.0 mg/kg body weight. Non-exploratory behaviors (permanency were not affected by benzodiazepine treatment. In the HL arm, exploration was not modified but permanency was increased in a dose-dependent manner. In the HH arm, exploration and permanency were not affected. Results are compatible with the idea that exploration-processing mechanisms in conflictive environments are modulated by fear-processing mechanisms of the brain.

  12. Temporal structure of the rat's behavior in elevated plus maze test.

    Science.gov (United States)

    Casarrubea, M; Roy, V; Sorbera, F; Magnusson, M S; Santangelo, A; Arabo, A; Crescimanno, G

    2013-01-15

    Aim of the research was to evaluate, by means of quantitative and multivariate temporal pattern analyses, the behavior of Wistar rat in elevated plus maze (EPM) test. On the basis of an ethogram encompassing 24 behavioral elements, quantitative results showed that 130.14 ± 8.01 behavioral elements occurred in central platform and in closed arms (protected zones), whereas 88.62 ± 6.04 occurred in open arms (unprotected zones). Percent distribution was characterized by a prevalence of sniffing, walking and vertical exploration. Analysis of minute-by-minute duration evidenced a decrease for time spent in open arms and central platform and an increase for time spent in closed arms. As to multivariate t-pattern analysis, 126 different temporal patterns were detected. Behavioral stripes, summarizing distribution of such t-patterns along time, showed that several t-patterns were not homogeneously distributed along the test observational period: t-patterns encompassing behavioral events occurring prevalently in central platform-open arms were observed during the first minutes, whereas t-patterns structured on the basis of events occurring mainly in central platform-closed arms were detected during the last minutes. Therefore, during the observation in elevated plus maze, rat's behavior undergoes significant rearrangements of its temporal features. Present research demonstrates, for the first time, the existence of complex and significantly timed behavioral sequences in the activity of Wistar rats tested in elevated plus maze. Application of t-pattern analysis can provide useful tools to characterize the behavioral dynamics of anxiety-related rodent behavior and differentiate the effect of various anxioselective substances.

  13. Individual differences in the elevated plus-maze and the forced swim test.

    Science.gov (United States)

    Estanislau, Celio; Ramos, Anna Carolina; Ferraresi, Paula Daniele; Costa, Naiara Fernanda; de Carvalho, Heloisa Maria Cotta Pires; Batistela, Silmara

    2011-01-01

    The elevated plus-maze is an apparatus composed of enclosed and open (elevated) arms and time spent in the open arms by a rat can be increased/decreased by anxiolytic/anxiogenic agents. In the forced swim test, floating behavior is used as an index of behavioral despair and can be decreased by antidepressant agents. As the comorbidity between anxiety and depression is a remarkable issue in human behavioral disorders, a possible relationship between the behaviors seen in the cited tests is of great relevance. In the present study, fifty-four male rats (Rattus norvegicus) were submitted to a plus-maze session and to a 2-day forced swim protocol. According to their time in the open arms, they were divided into three groups: Low Open, Medium Open and High Open. Some plus-maze measures were found to be coherent with time in the open arms and are suggested to also be reliable anxiety indexes. In the forced swim test, the Low Open group showed decreases in floating duration from forced swim Session 1 to Session 2, an alteration opposite to that observed in the other groups (particularly, the Medium Open group). The Low Open group also showed increases in floating latency, again in sharp contrast with the alteration found in the other groups. Accordingly, positive and negative correlation were found between time in the open arms and floating duration and latency, respectively. Results are compared to previous studies and mediation of the effect by reactivity to aversive stimulation or alterations induced by open arm exposure is discussed.

  14. Mazes and meso-islands: Impact of Ag preadsorption on Ge growth on Si(111)

    Science.gov (United States)

    Schmidt, Th.; Speckmann, M.; Flege, J. I.; Müller-Caspary, K.; Heidmann, I.; Kubelka-Lange, A.; Menteş, T. O.; Niño, M. Á.; Locatelli, A.; Rosenauer, A.; Falta, J.

    2016-12-01

    The preadsorption of Ag on Si(111) drastically changes the growth of Ge. In a temperature range from 400°C to 650°C, Ag adsorption on Si leads to the formation of a √{3 }×√{3 } -R 30° reconstruction that exhibits a maze-like morphology on the mesoscopic scale, as observed by low-energy electron diffraction (LEED) and low-energy electron microscopy. This maze morphology can be attributed to a surface roughening on an atomic scale, induced by the re-arrangement of top layer atoms during the 7 ×7 to √{3 }×√{3 } -R 30° transition. The subsequent deposition of Ge results in the formation of a wetting layer, the evolution of which has been found to be governed by the Ag/Si(111)-√{3 }×√{3 } -R 30° template's maze structure, as the latter offers a high density of heterogeneous nucleation sites. Upon further Ge growth, three-dimensional islands with diameters in the micrometer range are formed, which exhibit a large and flat (111) top facet. X-ray photoemission electron microscopy reveals that during Ge growth, Ag is segregating to the surface very efficiently. Grazing-incidence x-ray diffraction and transmission electron microscopy have been used to study the composition, strain state and defect structure of the Ge islands in dependence of the growth temperature. The strain induced by lattice mismatch is found to be largely relaxed (80-90% relaxation) in the investigated growth temperature range from 400 to 600°C, which is confirmed by high-resolution LEED measurements. As a main relaxation mechanism, the formation of interfacial misfit dislocations has been identified. Interdiffusion of Si into the Ge islands becomes more and more pronounced for increasing growth temperature, whereas the formation of twinned Ge regions can drastically be suppressed at higher temperature.

  15. [Analysis of variance of repeated data measured by water maze with SPSS].

    Science.gov (United States)

    Qiu, Hong; Jin, Guo-qin; Jin, Ru-feng; Zhao, Wei-kang

    2007-01-01

    To introduce the method of analyzing repeated data measured by water maze with SPSS 11.0, and offer a reference statistical method to clinical and basic medicine researchers who take the design of repeated measures. Using repeated measures and multivariate analysis of variance (ANOVA) process of the general linear model in SPSS and giving comparison among different groups and different measure time pairwise. Firstly, Mauchly's test of sphericity should be used to judge whether there were relations among the repeatedly measured data. If any (PSPSS statistical package is available to fulfil this process.

  16. Activation of the hippocampal complex during tactile maze solving in congenitally blind subjects

    DEFF Research Database (Denmark)

    Gagnon, Léa; Schneider, Fabien C; Siebner, Hartwig R

    2012-01-01

    Despite their lack of vision, congenitally blind subjects are able to build and manipulate cognitive maps for spatial navigation. It is assumed that they thereby rely more heavily on echolocation, proprioceptive signals and environmental cues such as ambient temperature and audition to compensate...... and parahippocampus, occipital cortex and fusiform gyrus. Blindfolded sighted controls did not show increased BOLD responses in these areas; instead they activated the caudate nucleus and thalamus. Both groups activated the precuneus during tactile maze navigation. We conclude that cross-modal plastic processes allow...

  17. Effects of histamine on MK-801-induced memory deficits in radial maze performance in rats.

    Science.gov (United States)

    Chen, Z; Zhao, Q; Sugimoto, Y; Fujii, Y; Kamei, C

    1999-08-21

    The effects of histamine on the spatial memory deficits induced by MK-801 were investigated using the eight-arm radial maze paradigm in rats. Intracerebroventricular (i.c.v.) injection of histamine or thioperamide, and intraperitoneal (i.p.) injection of histidine improved the spatial memory deficits induced by MK-801. Similar results were obtained with 2-thiazolylethylamine. In contrast, 4-methylhistamine showed no significant effect. Based on these observations, it seems likely that the protective effect of histamine on MK-801-induced spatial memory deficit is mediated by H(1)-receptors.

  18. Robotic excision of aortic valve papillary fibroelastoma and concomitant Maze procedure

    Directory of Open Access Journals (Sweden)

    Edward T Murphy

    2012-12-01

    Full Text Available Cardiothoracic surgeons have utilized the surgical robot to provide a minimally invasive approach to a number of intracardiac operations, including tumor resection, valve repair, and ablation of atrial arrhythmia. We report the case of a 58 year-old woman who was found to have a mobile mass on her aortic valve during evaluation of atrial fibrillation. Both of these conditions were addressed when she underwent a combined robotic biatrial Maze procedure and excision of the mass, which proved to be a papillary fibroelastoma of the aortic valve.

  19. Acute restriction impairs memory in the elevated T-maze (ETM) and modifies serotonergic activity in the dorsolateral striatum.

    Science.gov (United States)

    Cruz-Morales, Sara Eugenia; García-Saldívar, Norma Laura; González-López, María Reyes; Castillo-Roberto, Georgina; Monroy, Juana; Domínguez, Roberto

    2008-12-16

    Serotonin (5-HT) is involved in behaviors such as sleep, eating, memory, in mental disorders like anxiety and depression and plays an important role in the modulation of stress. On the other hand, exposure to stress influence learning as well as declarative and non-declarative memory. These effects are dependent on the type of stressor, their magnitude, and the type of memory. The striatum has been associated with non-declarative procedural memory, while the information about stress effects on procedural memory and their relation with striatal serotonin is scarce. The objective of this study was to evaluate the effects of stress on the modifications of the striatal serotonergic system. In Experiment 1, the effects of either 60 min of restraint (R) or exposure to the elevated T-maze (ETM) was assessed. Exposure to ETM decreased 5-HT concentration and to R increased 5-HT activity ([metabolite]/[neurotransmitter]). In Experiment 2, we evaluated the effects of restraint on ETM trained immediately, 24 or 48 h after restraint. No effects were detected in acquisition or escape latencies, while retention latencies were lower in all groups compared with the non-restrained group, although significant effects were detected immediately and 24h after restraint. The memory impairment seems to be associated with changes in striatal serotonergic system, given that 5-HT concentration increased, while serotonergic activity decreased. The differences in the activity of 5-HT detected in each experiment could be explained by the effects of different stressors on the serotonergic neurons ability to synthesize the neurotransmitter. Thus, we suggest that exposure to stress impairs procedural memory and that striatal serotonin modulates this effect.

  20. Robust training attenuates TBI-induced deficits in reference and working memory on the radial 8-arm maze

    Directory of Open Access Journals (Sweden)

    Veronica eSebastian

    2013-05-01

    Full Text Available Globally, it is estimated that nearly 10 million people sustain severe brain injuries leading to hospitalization and/or death every year. Amongst survivors, traumatic brain injury (TBI results in a wide variety of physical, emotional and cognitive deficits. The most common cognitive deficit associated with TBI is memory loss, involving impairments in spatial reference and working memory. However, the majority of research thus far has characterized the deficits associated with TBI on either reference or working memory systems separately, without investigating how they interact within in a single task. Thus we examined the effects of TBI on short-term working and long-term reference memory using the radial 8-arm maze (RAM with a sequence of 4 baited and 4 unbaited arms. Subjects were given 10 daily trials for 6 days followed by a memory retrieval test two weeks after training. Multiple training trials not only provide robust training, but also test the subjects’ ability to frequently update short-term memory while learning the reference rules of the task. Our results show that TBI significantly impaired short-term working memory function on previously acquired spatial information but has little effect on long-term reference memory. Additionally, TBI significantly increased working memory errors during acquisition and reference memory errors during retention testing two weeks later. With a longer recovery period after TBI, the robust RAM training mitigated the reference memory deficit in retention but not the short-term working memory deficit during acquisition. These results identify the resiliency and vulnerabilities of short-term working and long-term reference memory to TBI in the context of robust training. The data highlight the role of cognitive training and other behavioral remediation strategies implicated in attenuating deficits associated with TBI.

  1. A computational model for exploratory activity of rats with different anxiety levels in elevated plus-maze.

    Science.gov (United States)

    Costa, Ariadne A; Morato, Silvio; Roque, Antonio C; Tinós, Renato

    2014-10-30

    The elevated plus-maze is an apparatus widely used to study the level of anxiety in rodents. The maze is plus-shaped, with two enclosed arms and two open arms, and elevated 50cm from the floor. During a test, which usually lasts for 5min, the animal is initially put at the center and is free to move and explore the entire maze. The level of anxiety is measured by variables such as the percentage of time spent and the number of entries in the enclosed arms. High percentage of time spent at and number of entries in the enclosed arms indicate anxiety. Here we propose a computational model of rat behavior in the elevated plus-maze based on an artificial neural network trained by a genetic algorithm. The fitness function of the genetic algorithm is composed of reward (positive) and punishment (negative) terms, which are incremented as the computational agent (virtual rat) moves in the maze. The punishment term is modulated by a parameter that simulates the effects of different drugs. Unlike other computational models, the virtual rat is built independently of prior known experimental data. The exploratory behaviors generated by the model for different simulated pharmacological conditions are in good agreement with data from real rats.

  2. Water Associated Zero Maze: A novel rat test for long term traumatic re-experiencing

    Directory of Open Access Journals (Sweden)

    Gilad eRitov

    2014-01-01

    Full Text Available Often, freezing and startle behaviors in the context of a previously experienced stress are taken as an indication of posttraumatic stress disorder (PTSD-like symptoms in rats. However, PTSD is characterized by large individual variations of symptoms. In order to take into consideration the complex and long term distinctive variations in effects of trauma exposure additional behavioral measures are required.The current study used a novel behavioral test, the Water Associated Zero Maze (WAZM. This test was planned to enable a formation of an association between the context of the maze and an underwater trauma or swim stress in order to examine the impact of exposure to the context which immediately precedes a stressful or a traumatic experience on rat's complex behavior. Rats were exposed to the WAZM and immediately after to an underwater trauma or short swim. One month later rats were re-exposed to the context of the WAZM while their behavior was video recorded. Furthermore, c-Fos expression in the amygdala was measured 90 min after this exposure.The results of the current study indicate that the WAZM can be used to discern behavioral changes measured a long time after the actual traumatic or stressful events. Furthermore, the behavioral changes detected were accompanied by changes of c-Fos expression in the amygdala of exposed rats. We suggest that the WAZM can be used to model traumatic memories re-experiencing in rodent models of human stress-related pathologies such as PTSD.

  3. The effects of abused inhalants on mouse behavior in an elevated plus-maze.

    Science.gov (United States)

    Bowen, S E; Wiley, J L; Balster, R L

    1996-09-26

    Previous research has shown that abused inhalants (i.e., the volatile solvents) share some of the pharmacological properties of drugs used in the treatment of anxiety. In an attempt to further examine commonalities in the effects of inhalants and central nervous system depressant drugs, the behavioral effects of inhaled 1,1,1-trichloroethane, toluene, methoxyflurane and the convulsant vapor flurothyl were examined and compared to those of diazepam in the elevated plus-maze, a test used to predict antianxiety effects. After inhalant exposure or diazepam injection, mice were placed in the center of an elevated plus-maze and the number of entries and time spent in each type of arm (open versus closed) were measured during 5-min tests. Exposure to increasing concentrations of toluene produced concentration-related increases in the total number of open arm entries and the total time spent on the open arms, a pattern of behavioral effects similar to that produced by diazepam. A similar pattern was observed for increasing concentrations of 1,1,1-trichloroethane and methoxyflurane but changes in open arm activity were only observed at concentrations that increased locomotor activity. Conversely, only decreases in open arm time and number of entries were observed for flurothyl. The increasing evidence for commonalities in the behavioral effects of volatile solvents and depressant drugs may provide a foundation for understanding the neurobehavioral basis of inhalant abuse.

  4. Heading which way? Y-maze chemical assays: not all crustaceans are alike

    Science.gov (United States)

    Kenning, Matthes; Lehmann, Philipp; Lindström, Magnus; Harzsch, Steffen

    2015-09-01

    In a world full of chemicals, many crustaceans rely on elaborate olfactory systems to guide behaviors related to finding food or to assess the presence of conspecifics and predators. We analyzed the responses of the isopod Saduria entomon to a range of stimuli by which the animal is likely to encounter in its natural habitat using a Y-maze bioassay. In order to document the efficiency of the experimental design, the same bioassay was used to test the behavior of the crayfish Procambarus fallax whose ability to track odors is well documented. The crayfish performed well in the Y-maze and were able to locate the source of a food-related odor with high fidelity. The isopod S. entomon reacted indifferently or with aversion to most of the stimuli applied. In 1800 trials, only four out of 15 different stimuli yielded statistically significant results, and only one odorant was found to be significantly attractive. The findings raise several questions whether the stimuli presented and/or the experimental setup used represents an ecologically relevant situation for S. entomon. In each instance, our experiments illustrate that established methods cannot be readily transferred from one species to another.

  5. Possible anxiolytic effects of taurine in the mouse elevated plus-maze.

    Science.gov (United States)

    Chen, Si Wei; Kong, Wei Xi; Zhang, Yi Jing; Li, Yu Lei; Mi, Xiao Juan; Mu, Xiao Shuo

    2004-08-01

    The effects of taurine, an inhibitory amino acid, on the behavior of male mice were examined in the elevated plus-maze test of anxiety. Acute taurine treatment (60 mg/kg, PO) significantly increased the percentage of time spent in the open arms. Moreover, when taurine was administered daily for seven days and the plus-maze test was conducted 40 minutes after the last administration, a significant increase of the percentage of time in the open arms was observed even at dose of 2.5 mg/kg, however the open arm entries and the total entries were unaffected at any dose tested. In order to get a comprehensive profile of drug action, detailed behavioral analyses were further exerted. Single administration of 60 mg/kg taurine can significantly reduce the total rears. The results suggest that taurine have some anxiolytic-like properties, although its effects seem more limited and are not consistent with those presented by classic anxiolytics, such as diazepam.

  6. Coriandrum sativum: evaluation of its anxiolytic effect in the elevated plus-maze.

    Science.gov (United States)

    Emamghoreishi, Masoumeh; Khasaki, Mohammad; Aazam, Maryam Fath

    2005-01-15

    The clinical applications of benzodiazepines as anxiolytics are limited by their unwanted side effects. Therefore, the development of new pharmacological agents is well justified. Among medicinal plants, Coriandrum sativum L. has been recommended for relief of anxiety and insomnia in Iranian folk medicine. Nevertheless, no pharmacological studies have thus far evaluated its effects on central nervous system. Therefore, the aim of this study was to examine if the aqueous extract of Coriandrum sativum seed has anxiolytic effect in mice. Additionally, its effect on spontaneous activity and neuromuscular coordination were evaluated. The anxiolytic effect of aqueous extract (10, 25, 50, 100 mg/kg, i.p.) was examined in male albino mice using elevated plus-maze as an animal model of anxiety. The effects of the extract on spontaneous activity and neuromuscular coordination were assessed using Animex Activity Meter and rotarod, respectively. In the elevated plus-maze, aqueous extract at 100 mg/kg showed an anxiolytic effect by increasing the time spent on open arms and the percentage of open arm entries, compared to control group. Aqueous extract at 50, 100 and 500 mg/kg significantly reduced spontaneous activity and neuromuscular coordination, compared to control group. These results suggest that the aqueous extract of Coriandrum sativum seed has anxiolytic effect and may have potential sedative and muscle relaxant effects.

  7. Air-kerma evaluation at the maze entrance of HDR brachytherapy facilities.

    Science.gov (United States)

    Pujades, M C; Granero, D; Vijande, J; Ballester, F; Perez-Calatayud, J; Papagiannis, P; Siebert, F A

    2014-12-01

    In the absence of procedures for evaluating the design of brachytherapy (BT) facilities for radiation protection purposes, the methodology used for external beam radiotherapy facilities is often adapted. The purpose of this study is to adapt the NCRP 151 methodology for estimating the air-kerma rate at the door in BT facilities. Such methodology was checked against Monte Carlo (MC) techniques using the code Geant4. Five different facility designs were studied for (192)Ir and (60)Co HDR applications to account for several different bunker layouts.For the estimation of the lead thickness needed at the door, the use of transmission data for the real spectra at the door instead of the ones emitted by (192)Ir and (60)Co will reduce the lead thickness by a factor of five for (192)Ir and ten for (60)Co. This will significantly lighten the door and hence simplify construction and operating requirements for all bunkers.The adaptation proposed in this study to estimate the air-kerma rate at the door depends on the complexity of the maze: it provides good results for bunkers with a maze (i.e. similar to those used for linacs for which the NCRP 151 methodology was developed) but fails for less conventional designs. For those facilities, a specific Monte Carlo study is in order for reasons of safety and cost-effectiveness.

  8. A multitasking behavioral study based on combined Morris water maze and Y maze in mice%基于小鼠Morris水迷宫和Y迷宫联合试验的多任务行为学测试研究

    Institute of Scientific and Technical Information of China (English)

    孔林林; 张军; 乔枫; 祁金顺

    2013-01-01

    distances and the total time elapsed and distances swam in target quadrant between combined group and MWM only group.In Y maze tests,the total errors in combined group,compared with the Y maze only group,did not change on testing days 1 and 2 (P > 0.05).However,the total errors significantly decreased in combined group (P < 0.05) on testing days 3 and 4.Conclusion:The combined sequential behavioral tests did not interfere with the spatial learning and memory of mice in MWM.It also did not influence the working memory of mice in Y maze at 1st and 2nd day,but the combined training more than 2 days could enhance the working memory of mice.Therefore,the present study provides experimental evidence for combing spatial memory and working memory of mice,and suggests that reasonably combining different behavioral experiments will be helpful for increasing ex-perimental efficiency and decreasing experimental expenses.

  9. Pre-training in a radial arm maze abolished anxiety and impaired habituation in C57BL6/J mice treated with dizocilpine.

    Science.gov (United States)

    Abuhamdah, R M; Hussain, M D; Chazot, P L; Ennaceur, A

    2016-10-01

    Familiarity can imply a reduction of fear and anxiety, which may render learning and memory performance insensitive to NMDA receptor antagonism. Our previous study indicates that MK-801 (dizocilpine), NMDA antagonist, increased anxiety and prevented the acquisition of a spatial memory task. Here, we examined whether MK-801 will produce anxiety in mice that were familiar with the test environment. Male C57BL/6J mice were exposed, one session a day for 7days, to a 3D maze, which consisted of nine arms attached to upward inclined bridges radiating from a nonagonal platform. In this maze, high anxiety mice avoid the arms in the first sessions. One group of mice received saline (SAL) while a second group received MK-801 (MKD1), both on day one. A third group received saline in the first 3 sessions, and MK 801 in subsequent sessions (MKD4). Saline and MK-801 (0.1mg/kg) were administered intraperitoneally 30min before the test. MKD4 mice demonstrated an increase in bridge and arm visits, and reached arm/bridge entries ratio close to 1 in session 5. SAL mice also crossed frequently onto the arms, and reached a comparable ratio, but this was achieved with a lower number of arm visits. MKD1 mice demonstrated a reduced number of arm visits in each session compared to SAL and MKD4 mice. Dizocilpine produced anxiety in mice treated from day 1 of the test, but not in those treated from day 4. It also impaired habituation in animals familiar with the test environment; it produced sustained non-habituating hyperactivity.

  10. Autonomous robotics and deep learning

    CERN Document Server

    Nath, Vishnu

    2014-01-01

    This Springer Brief examines the combination of computer vision techniques and machine learning algorithms necessary for humanoid robots to develop "true consciousness." It illustrates the critical first step towards reaching "deep learning," long considered the holy grail for machine learning scientists worldwide. Using the example of the iCub, a humanoid robot which learns to solve 3D mazes, the book explores the challenges to create a robot that can perceive its own surroundings. Rather than relying solely on human programming, the robot uses physical touch to develop a neural map of its en

  11. Materialising power struggles of political imprisonment at Long Kesh/Maze prison, Northern Ireland

    DEFF Research Database (Denmark)

    McAtackney, Laura

    2015-01-01

    Prisons were one of the main arenas for contestation of rights, status and power during the course of the Northern Irish Troubles (c1969-c1998). A substantial number of the prisoners publicly denied the legitimacy of the state to imprison them and all those interned, remanded or convicted...... for paramilitary-related offences claimed political status. When a prison body communalises and actively contests its imprisonment the resulting power struggle become one of the most explicit witnessed in modern, capitalist societies. This paper explores Long Kesh/Maze prison, one of the seminal places...... of imprisonment during the conflict. It was a site where a number of major events emanated from, often catalyzing responses in wider society, as well as being the source of ongoing issues with ‘non-complying’ prisoners. It was a constant source of anxiety for the Northern Ireland and British governments...

  12. Use of maze in cyclotron hoppers; Utilizacao de labirinto em bunker de ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Fernando A.; Alves, Juliano S.; Fochesatto, Cintia; Cerioli, Luciane; Borges, Joao Alfredo; Gonzalez, Delfin; Silva, Daniel C., E-mail: fernandofernandes@biofarmaco.com.br [Delfin Farmacos e Derivados (Biofarmaco Marcadores Moleculares), Lauro de Freitas, BA (Brazil)

    2013-07-01

    Introduction: the increasing number of cyclotrons in Brazil due to constitutional amendment 49 /06 that enabled the production of radiopharmaceuticals with a short half - life by private companies. The radionuclides used for PET - CT require production centers near or within the diagnostic centers. In order to minimize maintenance and operating risks, gaining efficiency, our facility was the first in Brazil to use the access to a cyclotron bunker via maze, rather than armored door stopper type. Materials: the design calculations were based on the Monte Carlo method (MCNP5 - Monte Carlo N-Particletransportcode version 5). At the ends of the labyrinth are installed a door of polyethylene, for thermalization of neutrons, and other of wood for limiting access. Both legs of the maze have wall thickness of 100cm. In inspection Brazilian CNEN realize measures of dose rate for neutrons and gamma 9 points: 7 around the bunker, 1 over the bunker and 1 in the exhaust with the cyclotron operating with maximum load, double beam of 50uA for 2 hours. After commissioning were carried out around the bunker, the following measures: cumulative dose in three months with dosimeters for neutron rate dose with a gas proportional detector type filled with {sup 3}He and polyethylene neutron moderator and dose rate with a Geiger - Mueller detector for gamma radiation. Readings with neutron detectors were classified as background radiation and dose rates were always below the limits established in standard EN 3.01, and the calculation of the predicted regardless of the intensity of irradiation inside the bunker. Conclusion: the use of labyrinths as a way to access the bunkers cyclotron has been shown to be effective as the radiation shielding and efficient by allowing quick and easy access, virtually eliminating the maintenance.

  13. Phencyclidine (PCP) produces sexually dimorphic effects on voluntary sucrose consumption and elevated plus maze behavior.

    Science.gov (United States)

    Turgeon, Sarah M; Anderson, Nicole; O'Loughlin, Kerry

    2010-04-01

    Previous research in our laboratory indicates that the psychotomimetic drug phencyclidine (PCP) reduces voluntary sucrose consumption in male rats, potentially modeling the schizophrenic symptom of anhedonia. Given reports from the clinical literature that schizophrenia has a later age of onset and more favorable outcome in females, PCP might be expected to have sexually dimorphic effects in animal models of schizophrenia such as PCP-induced decreases in voluntary sucrose consumption. Young adult (66 days old) and adult (109 days old) male and female rats were trained to drink sucrose during a 30 min/day presentation protocol. On the day prior to the test day, animals were treated with PCP (15 mg/kg) or saline four hours after the onset of the sucrose presentation (20 h prior to the sucrose on the test day). PCP decreased sucrose consumption on the test day similarly in adult males and females, although females also showed decreased water consumption. In young animals, PCP decreased sucrose consumption in males but not in females. These results are consistent with the prediction that females will be less sensitive to the schizophrenia-like behavioral effects of PCP. In a separate study, the same animals were tested in an elevated plus maze one to two months after testing for voluntary sucrose consumption. Significant sex x drug interaction effects on a number of measures in the elevated plus maze indicated that prior exposure to PCP had an anxiolytic effect in females and an anxiogenic effect in males. While unexpected, this finding indicates an additional sexually dimorphic effect of PCP on behavior and its potential relevance to the PCP model of schizophrenia is discussed. 2010 Elsevier Inc. All rights reserved.

  14. Effects of apomorphine on rat behavior in the elevated plus-maze.

    Science.gov (United States)

    Garcia, Andrea Milena Becerra; Martinez, Raquel; Brandão, Marcus Lira; Morato, Silvio

    2005-07-21

    It has been reported that novelty may evoke both an exploratory and a fear drive, thus generating behavior responding to an approach/avoidance conflict. However, not much is known about the approach component. Whereas there exists abundant evidence referring to the avoidance component as the main target for the anxiolytic action of benzodiazepines, the involvement of dopaminergic mechanisms in fear and anxiety is controversial. The present study examined the effects of the dopaminergic agonist apomorphine, the D(2) dopaminergic antagonist sulpiride and the combined treatment sulpiride plus apomorphine on conventional and non-conventional measures of the behavior of rats exposed to an elevated plus-maze. Systemic injection of apomorphine (0.25, 0.5 and 1.0 mg/kg) caused a selective increase in the time spent in the open arms and in the open arm extremities. Pre-treatment with sulpiride blocked these effects while this dopaminergic antagonist had no effect by its own. Apomorphine produced no significant effects on stretching, flat-back-approach or scanning. Therefore, apomorphine increased the behavioral response linked to the approach component of the conflict without affecting risk assessment behaviors. These findings suggest that dopaminergic mechanisms, probably through D(2) receptors, may also be involved in the mediation of the conflict derived from the need of gathering information for confirming, identifying and localizing danger and take the appropriate action for avoiding the threatening stimuli of the elevated plus-maze. A role for dopaminergic mechanisms in the setting up of adaptive responses in a fear-inducing environment is discussed.

  15. Effects of prenatal methylazoxymethanol acetate (MAM) treatment in rats on water maze performance.

    Science.gov (United States)

    Leng, Andreas; Jongen-Rêlo, Ana L; Pothuizen, Helen H J; Feldon, Joram

    2005-06-20

    Prenatal methylazoxymethanol acetate (MAM) treatment has been shown to induce morphological abnormalities in cortical areas of the offspring. Based on the neuroanatomical and behavioural abnormalities, this treatment has been suggested as a useful animal model for schizophrenia. In a previous study (Jongen-Relo AL, Leng A, Luber M, Pothuizen HHJ, Weber L, Feldon J. The prenatal methylazoxymethanol acetate treatment: a neurodevelopmental animal model for schizophrenia? Behav Brain Res 2004;149:159-81) we have studied MAM-treated animals in a series of behavioural tests related to schizophrenia, such as latent inhibition and pre-pulse inhibition of the acoustic startle response to establish the validity of prenatal MAM treatment (20mg/kg i.p. on gestational days 9-15; MAM 9-MAM 15). We found that, apart from a marginal effect of increased activity in the open field, the MAM treatment on gestational day 15 was behaviourally ineffective. Here, we extended our previous study to a water maze experiment conducted in the same batch of animals as presented previously (MAM 12-MAM 15). MAM-treated animals showed similar water maze performance compared with control animals during the acquisition phase and the probe tests. However, during the reversal phase, MAM 15 animals showed impaired acquisition of the new platform location. This might indicate some cognitive deficits in MAM 15 animals in terms of working memory or behavioural flexibility. However, in combination with the lack of behavioural abnormalities of MAM 12-MAM 15 animals in several other tests related to schizophrenia in the previously reported study, the use of MAM treatment (MAM 12-MAM 15) as a valid model for schizophrenia still remains debatable.

  16. Validation of an automated system for measuring anxiety-related behaviours in the elevated plus maze.

    Science.gov (United States)

    Sidor, Michelle M; Rilett, Kelly; Foster, Jane A

    2010-04-30

    The elevated plus maze (EPM) is one of the most widely used and established tests to assess anxiety-related behaviours and has been validated for use in both mice and rats. Although relatively quick and simple to conduct, there always exists the potential for observer bias during data collection. The KinderScientific EPM system uses a series of apparatus-embedded photobeams to collect spatiotemporal measures such as the amount of time spent in each zone of the maze (centre, open and closed arms), and the frequency of arm entries. Risk assessment behaviours, such as head dips and protected stretches, are also measured which represents a unique feature of this system over other automated EPM systems. We compared observer derived spatiotemporal and risk assessment measurements with automated generated data to test the reliability and accuracy of the automated system. Data were manually collected using different zone entry/exit criteria (2 vs. 4 paws). Automated data were generated using both the default zone map provided with the system and a user-modified zone map. We show that the automated EPM provides accurate and reliable measurements of both spatiotemporal and risk assessment behaviours. In addition, we show that the default zone map overestimated visually observed arm entries while our modified zone map generated data comparable to manually generated data using a 4 paws open arm entry criteria which is most consistently used to define arm entry in the literature. The KinderScientific automated EPM system represents a reliable tool for collection of a wide range of anxiety-related behavioural measures.

  17. Extra-pericardial tamponade following Wolf Mini-Maze procedure: a case report.

    Science.gov (United States)

    Bailey, James P

    2015-11-05

    Extra-pericardial tamponade is a rare life threatening condition that has not previously been reported in association with Wolf Mini-Maze procedures. In this case, atypical presentation of cardiac tamponade caused by postoperative anticoagulation resulted in a second hospitalization, a second surgery, and delayed recovery time. The goal of this case report is to increase awareness about a life threatening complication that can occur following minimally invasive cardiac surgery. A 60 year old male with long standing essential hypertension, who was recently treated for atrial fibrillation utilizing the Wolf Mini-Maze procedure, experienced a postoperative international normalized ratio increase from 3.6 to 5.3 over the course of six days. Fifteen days postoperatively, the patient experienced mild exercise intolerance, his condition rapidly progressed to a constellation of symptoms including severe exercise intolerance, dyspnea, hypotension, and near syncope. A diagnosis of cardiac tamponade was made, and the patient was re-admitted to the hospital. Attempts to reverse his warfarin anticoagulation with fresh frozen plasma and vitamin K were unsuccessful after 24 h. Video-assisted thoracotomy was performed to relieve the tamponade, and during surgery he was diagnosed with extra-pericardial tamponade caused by an extensive hematoma. Complications due to anticoagulation therapy required this re-admission, additional surgery, and delayed recovery. The patient has since recovered completely with no long term morbidities and is asymptomatic three years following initial presentation. This case marks the first time extra-pericardial tamponade has been reported post cardiothoracic intervention in English literature. Many surgical procedures require postoperative anticoagulation; in the past, warfarin has been the standard of care due to its purported reversibility. This case provides an example of the challenge presented when anticoagulating with warfarin, and the reversal of

  18. The Key of the Maze: The role of mental imagery and cognitive flexibility in navigational planning.

    Science.gov (United States)

    Bocchi, Alessia; Carrieri, Marika; Lancia, Stefania; Quaresima, Valentina; Piccardi, Laura

    2017-06-09

    Spatial navigation planning ability relies on both mental imagery and cognitive flexibility. Considering the importance of planning ability in everyday life, several neuropsychological tests are used in clinical practice for its assessment, although some of these are not aimed at assessing the strategies of navigational planning. The Porteus Maze Test (PMT) and the Key Search Task (KST) require to plan a strategy in a maze and in an imagined space, respectively. To the best of our knowledge, although these two tests share some features, the relationship between them has never been explored. The purpose of the present study was to investigate, for the first time, the relationship between the PMT and the KST performances in 38 healthy subjects in order to understand the implications of this association for the assessment of spatial navigation ability. Subjects were subdivided in bad or good navigation planners on the basis of the their KST score. The results of the study have revealed a significant difference (t=2.35; p=0.03) in the number of errors made at the PMT by bad navigational planners (0.78±0.28) and good navigational planners (0.10±0.06). The first group (bad navigational planners) made more errors at the PMT than the good navigational planners (who made less errors at the PMT). This provides evidence of the possibility to use the KST and the PMT in a combined way as a new tool for the assessment of spatial navigational planning ability. Furthermore, this finding highlights the importance of mental imagery and cognitive flexibility in spatial navigation, suggesting that these functions could be the link between a good planning ability and a successful spatial navigation. In conclusion, this study suggests that an efficient navigation would not be possible without a good navigational planning ability. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. [The role of motivation in the performance of a conditioned switching-over of the maze habit in ants Myrmica rubra after a change in the quality of the food reinforcement].

    Science.gov (United States)

    Udalova, G P; Karas', A Ia

    2005-01-01

    Active foragers Myrmica rubra were trained in a maze under conditions of different levels of colony need in food with carbohydrate (sugar syrup) or protein (ants Lasius niger pupae) reinforcement. Acquisition of the maze habit was better under conditions of reinforcement with pupae, especially by its time indices. Ants were able to modify the acquired habit when the reinforcement quality was changed. It was shown that learning was possible only when the colony and after a change pupae for the syrup was "hungry". Under these conditions, after a change of the syrup for pupae or visa versa the previously acquired optimum habit was transferred. Several hours later, with satiation of the colony, food reactions learned with protein reinforcement switched-over to "stochastic" non-optimized behavior with the dominance of exploratory reactions. Thus, it was shown that higher social insects ants were capable for conditioned switching-over. Different forms of this phenomenon depended on the level of the colony need in food and, consequently, on the level of the social food motivation of foragers ants.

  20. Induction of habits in rats by a forced-choice procedure in T-maze and the effect of pre-test free exploration

    DEFF Research Database (Denmark)

    Moustgaard, Anette; Hau, Jann

    2009-01-01

    A forced-choice procedure in T-maze designed for the induction of habits was used to induce strong habits in rats. The response choices of rats in 20 free-choice trials were compared after the rats had been subjected to 1 or 200 forced-choice trials to one side of the T-maze. After 200 forced-cho...

  1. Classification Accuracy of Oral Reading Fluency and Maze in Predicting Performance on Large-Scale Reading Assessments

    Science.gov (United States)

    Decker, Dawn M.; Hixson, Michael D.; Shaw, Amber; Johnson, Gloria

    2014-01-01

    The purpose of this study was to examine whether using a multiple-measure framework yielded better classification accuracy than oral reading fluency (ORF) or maze alone in predicting pass/fail rates for middle-school students on a large-scale reading assessment. Participants were 178 students in Grades 7 and 8 from a Midwestern school district.…

  2. Fear-potentiation in the elevated plus-maze test depends on stressor controllability and fear conditioning

    NARCIS (Netherlands)

    Korte, S M; Bohus, B; de Boer, Sietse

    The purpose of the study was to determine which stressor qualities (escapable vs. inescapable stress and unconditioned vs. conditioned stress) can potentiate fear in the elevated plus-maze. While inescapable stress potentiated fear, escapable stress did not, but escapable stress increased the

  3. Fear-potentiation in the elevated plus-maze test depends on stressor controllability and fear conditioning

    NARCIS (Netherlands)

    Korte, S M; Bohus, B; de Boer, Sietse

    1999-01-01

    The purpose of the study was to determine which stressor qualities (escapable vs. inescapable stress and unconditioned vs. conditioned stress) can potentiate fear in the elevated plus-maze. While inescapable stress potentiated fear, escapable stress did not, but escapable stress increased the locomo

  4. Classification Accuracy of Oral Reading Fluency and Maze in Predicting Performance on Large-Scale Reading Assessments

    Science.gov (United States)

    Decker, Dawn M.; Hixson, Michael D.; Shaw, Amber; Johnson, Gloria

    2014-01-01

    The purpose of this study was to examine whether using a multiple-measure framework yielded better classification accuracy than oral reading fluency (ORF) or maze alone in predicting pass/fail rates for middle-school students on a large-scale reading assessment. Participants were 178 students in Grades 7 and 8 from a Midwestern school district.…

  5. The Canine Sand Maze: An Appetitive Spatial Memory Paradigm Sensitive to Age-Related Change in Dogs

    Science.gov (United States)

    Salvin, Hannah E.; McGreevy, Paul D.; Sachdev, Perminder S.; Valenzuela, Michael J.

    2011-01-01

    Aged dogs exhibit a spectrum of cognitive abilities including a syndrome similar to Alzheimer's disease. A major impediment to research so far has been the lack of a quick and accurate test of visuospatial memory appropriate for community-based animals. We therefore report on the development and validation of the Canine Sand Maze. A 4.5-m-diameter…

  6. The relationships between trait anxiety, place recognition memory, and learning strategy.

    Science.gov (United States)

    Hawley, Wayne R; Grissom, Elin M; Dohanich, Gary P

    2011-01-20

    Rodents learn to navigate mazes using various strategies that are governed by specific regions of the brain. The type of strategy used when learning to navigate a spatial environment is moderated by a number of factors including emotional states. Heightened anxiety states, induced by exposure to stressors or administration of anxiogenic agents, have been found to bias male rats toward the use of a striatum-based stimulus-response strategy rather than a hippocampus-based place strategy. However, no study has yet examined the relationship between natural anxiety levels, or trait anxiety, and the type of learning strategy used by rats on a dual-solution task. In the current experiment, levels of inherent anxiety were measured in an open field and compared to performance on two separate cognitive tasks, a Y-maze task that assessed place recognition memory, and a visible platform water maze task that assessed learning strategy. Results indicated that place recognition memory on the Y-maze correlated with the use of place learning strategy on the water maze. Furthermore, lower levels of trait anxiety correlated positively with better place recognition memory and with the preferred use of place learning strategy. Therefore, competency in place memory and bias in place strategy are linked to the levels of inherent anxiety in male rats.

  7. Multivariate temporal pattern analysis applied to the study of rat behavior in the elevated plus maze: methodological and conceptual highlights.

    Science.gov (United States)

    Casarrubea, M; Magnusson, M S; Roy, V; Arabo, A; Sorbera, F; Santangelo, A; Faulisi, F; Crescimanno, G

    2014-08-30

    Aim of this article is to illustrate the application of a multivariate approach known as t-pattern analysis in the study of rat behavior in elevated plus maze. By means of this multivariate approach, significant relationships among behavioral events in the course of time can be described. Both quantitative and t-pattern analyses were utilized to analyze data obtained from fifteen male Wistar rats following a trial 1-trial 2 protocol. In trial 2, in comparison with the initial exposure, mean occurrences of behavioral elements performed in protected zones of the maze showed a significant increase counterbalanced by a significant decrease of mean occurrences of behavioral elements in unprotected zones. Multivariate t-pattern analysis, in trial 1, revealed the presence of 134 t-patterns of different composition. In trial 2, the temporal structure of behavior become more simple, being present only 32 different t-patterns. Behavioral strings and stripes (i.e. graphical representation of each t-pattern onset) of all t-patterns were presented both for trial 1 and trial 2 as well. Finally, percent distributions in the three zones of the maze show a clear-cut increase of t-patterns in closed arm and a significant reduction in the remaining zones. Results show that previous experience deeply modifies the temporal structure of rat behavior in the elevated plus maze. In addition, this article, by highlighting several conceptual, methodological and illustrative aspects on the utilization of t-pattern analysis, could represent a useful background to employ such a refined approach in the study of rat behavior in elevated plus maze. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Dose reduction of scattered photons from concrete walls lined with lead: Implications for improvement in design of megavoltage radiation therapy facility mazes

    Energy Technology Data Exchange (ETDEWEB)

    Al-Affan, I. A. M., E-mail: info@medphys-environment.co.uk; Hugtenburg, R. P.; Piliero, M. [Swansea University, Swansea SA2 8PP (United Kingdom); Bari, D. S. [Swansea University, Swansea SA2 8PP, United Kingdom and University of Zakho, Duhok (Iraq); Al-Saleh, W. M. [Swansea University, Swansea SA2 8PP, United Kingdom and King Saud Bin Abdulaziz University for Health Science, Hofuf (Saudi Arabia); Evans, S. [Department of Medical Physics and Clinical Engineering, Singleton Hospital, Swansea SA2 8QA (United Kingdom); Al-Hasan, M.; Al-Zughul, B. [College of Sciences, Zarqa University, Zarqa (Jordan); Al-Kharouf, S. [The Royal Scientific Society, Amman (Jordan); Ghaith, A. [Association of Arab Universities, Amman (Jordan)

    2015-02-15

    Purpose: This study explores the possibility of using lead to cover part of the radiation therapy facility maze walls in order to absorb low energy photons and reduce the total dose at the maze entrance of radiation therapy rooms. Methods: Experiments and Monte Carlo simulations were utilized to establish the possibility of using high-Z materials to cover the concrete walls of the maze in order to reduce the dose of the scattered photons at the maze entrance. The dose of the backscattered photons from a concrete wall was measured for various scattering angles. The dose was also calculated by the FLUKA and EGSnrc Monte Carlo codes. The FLUKA code was also used to simulate an existing radiotherapy room to study the effect of multiple scattering when adding lead to cover the concrete walls of the maze. Monoenergetic photons were used to represent the main components of the x ray spectrum up to 10 MV. Results: It was observed that when the concrete wall was covered with just 2 mm of lead, the measured dose rate at all backscattering angles was reduced by 20% for photons of energy comparable to Co-60 emissions and 70% for Cs-137 emissions. The simulations with FLUKA and EGS showed that the reduction in the dose was potentially even higher when lead was added. One explanation for the reduction is the increased absorption of backscattered photons due to the photoelectric interaction in lead. The results also showed that adding 2 mm lead to the concrete walls and floor of the maze reduced the dose at the maze entrance by up to 90%. Conclusions: This novel proposal of covering part or the entire maze walls with a few millimeters of lead would have a direct implication for the design of radiation therapy facilities and would assist in upgrading the design of some mazes, especially those in facilities with limited space where the maze length cannot be extended to sufficiently reduce the dose.

  9. Learning

    Directory of Open Access Journals (Sweden)

    Mohsen Laabidi

    2014-01-01

    Full Text Available Nowadays learning technologies transformed educational systems with impressive progress of Information and Communication Technologies (ICT. Furthermore, when these technologies are available, affordable and accessible, they represent more than a transformation for people with disabilities. They represent real opportunities with access to an inclusive education and help to overcome the obstacles they met in classical educational systems. In this paper, we will cover basic concepts of e-accessibility, universal design and assistive technologies, with a special focus on accessible e-learning systems. Then, we will present recent research works conducted in our research Laboratory LaTICE toward the development of an accessible online learning environment for persons with disabilities from the design and specification step to the implementation. We will present, in particular, the accessible version “MoodleAcc+” of the well known e-learning platform Moodle as well as new elaborated generic models and a range of tools for authoring and evaluating accessible educational content.

  10. The neutron dose equivalent evaluation and shielding at the maze entrance of a Varian Clinac 23EX treatment room

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xudong; Esquivel, Carlos; Nes, Elena; Shi Chengyu; Papanikolaou, Nikos; Charlton, Michael [University of Texas Health Science Center, San Antonio, Texas 78229 (United States); South Texas Accelerated Research Therapeutics (START) Center for Cancer Care, San Antonio, Texas 78229 (United States); University of Texas Health Science Center, San Antonio, Texas 78229 (United States)

    2011-03-15

    Purpose: To evaluate the neutron and photon dose equivalent rate (H{sub n,D} and H{sub G}) at the outer maze entrance and the adjacent treatment console area after the installation of a Varian Clinac 23EX accelerator with a higher beam energy than its predecessor. The evaluation was based on measurements and comparison with several empirical calculations. The effectiveness of borated polyethylene (BPE) boards, as a maze wall lining material, on neutron dose and photon dose reduction is also reported. Methods: A single energy Varian 6 MV photon linear accelerator (linac) was replaced with a Varian Clinac 23EX accelerator capable of producing 18 MV photons in a vault originally designed for the former accelerator. In order to evaluate and redesign the shielding of the vault, the neutron dose equivalent H{sub n,D} was measured using an Andersson-Braun neutron Rem meter and the photon dose equivalent H{sub G} was measured using a Geiger Mueller and an ion chamber {gamma}-ray survey meter at the outer maze entrance. The measurement data were compared to semiempirical calculations such as the Kersey method, the modified Kersey method, and a newly proposed method by Falcao et al. Additional measurements were taken after BPE boards were installed on the maze walls as a neutron absorption lining material. Results: With the gantry head tilted close to the inner maze entrance and with the jaws closed, both neutron dose equivalent and photon dose equivalent reached their maximum. Compared to the measurement results, the Kersey method overestimates the neutron dose equivalent H{sub n,D} by about two to four times (calculation/measurement ratio{approx_equal}2.4-3.8). Falcao's method largely overestimates the H{sub n,D} (calculation/measurement ratio{approx_equal}3.9-5.5). The modified Kersey method has a calculation to measurement ratio about 0.6-0.9. The photon dose equivalent calculation including McGinley's capture gamma dose equivalent equation estimates about 77

  11. Myristic Acid Produces Anxiolytic-Like Effects in Wistar Rats in the Elevated Plus Maze

    Directory of Open Access Journals (Sweden)

    Carlos M. Contreras

    2014-01-01

    Full Text Available A mixture of eight fatty acids (linoleic, palmitic, stearic, myristic, elaidic, lauric, oleic, and palmitoleic acids at similar concentrations identified in human amniotic fluid produces anxiolytic-like effects comparable to diazepam in Wistar rats. However, individual effects of each fatty acid remain unexplored. In Wistar rats, we evaluated the separate action of each fatty acid at the corresponding concentrations previously found in human amniotic fluid on anxiety-like behaviour. Individual effects were compared with vehicle, an artificial mixture of the same eight fatty acids, and a reference anxiolytic drug (diazepam, 2 mg/kg. Myristic acid, the fatty acid mixture, and diazepam increased the time spent in the open arms of the elevated plus maze and reduced the anxiety index compared with vehicle, without altering general locomotor activity. The other fatty acids had no effect on anxiety-like behaviour, but oleic acid reduced locomotor activity. Additionally, myristic acid produced anxiolytic-like effects only when the concentration corresponded to the one identified in human amniotic fluid (30 g/mL but did not alter locomotor activity. We conclude that of the eight fatty acids contained in the fatty acid mixture, only myristic acid produces anxiolytic-like effects when administered individually at a similar concentration detected in human amniotic fluid.

  12. Molecular docking and panicolytic effect of 8-prenylnaringenin in the elevated T-maze.

    Science.gov (United States)

    Bagatin, Mariane Cristovão; Tozatti, Camila Santos Suniga; Abiko, Layara Akemi; Yamazaki, Diego Alberto dos Santos; Silva, Priscila Rebeca Alves; Perego, Leonardo Martins; Audi, Elisabeth Aparecida; Seixas, Flavio Augusto Vicente; Basso, Ernani Abicht; Gauze, Gisele de Freitas

    2014-01-01

    The purpose of this study was to investigate the effects of the chronic administration of a racemic mixture of 8-prenylnaringenin (8-PN) on rats submitted to the elevated T-maze (ETM) model of generalized anxiety and panic disorders. The selective serotonin (SERT) reuptake inhibitor fluoxetine was used as a positive control. Rat locomotion was assessed in a circular arena following each drug treatment. The administration of racemic 8-PN for 21 d in rats increased one-way escape latencies from the ETM open arm, indicating a panicolytic effect. To evaluate the interactions of 8-PN with monoamine transporters, a docking study was performed for both the R and S configurations of 8-PN towards SERT, norepinephrine (NET) and dopamine transporters (DAT). The application of the docking protocol showed that (R)-8-PN provides greater affinity to all transporters than does the S enantiomer. This result suggests that enantiomer (R)-8-PN is the active form in the in vivo test of the racemic mixture.

  13. Cox-Maze III procedure with valvular surgery in an autopneumonectomized patient

    Directory of Open Access Journals (Sweden)

    Wi Jin

    2012-11-01

    Full Text Available Abstract Destructive pulmonary inflammation can leave patients with only a single functional lung, resulting in anatomical and physiological changes that may interfere with subsequent cardiac surgeries. Such patients are vulnerable to perioperative cardiopulmonary complications. Herein, we report the first case, to our knowledge, of an autopneumonectomized patient who successfully underwent a modified Cox-Maze III procedure combined with valvular repairs. The three major findings in this case can be summarized as follows: (1 a median sternotomy with peripheral cannulations, such as femoral cannulations, can provide an optimal exposure and prevent the obstruction of vision that may occur as a result of multiple cannulations through a median sternotomy; (2 a modified septal incision combined with biatrial incisions facilitate adequate exposure of the mitral valve; and (3 the aggressive use of intraoperative ultrafiltration may be helpful for the perioperative managements as decreasing pulmonary water contents, thereby avoiding the pulmonary edema associated with secretion of inflammatory cytokines during a cardiopulmonary bypass. We also provide several suggestions for achieving similar satisfactory surgical outcomes in patients with a comparable condition.

  14. Serotonin in anxiety and panic: contributions of the elevated T-maze.

    Science.gov (United States)

    Zangrossi, Hélio; Graeff, Frederico G

    2014-10-01

    The elevated T-maze (ETM) was developed to test the hypothesis that serotonin (5-HT) plays an opposing role in the regulation of defensive behaviors associated with anxiety and panic. This test allows the measurement in the same rat of inhibitory avoidance acquisition, related to generalized anxiety disorder, and of one-way escape, associated with panic disorder. The evidence so far reported with the ETM supports the above hypothesis and indicates that: (1) whereas 5-HT neurons located at the dorsal raphe nucleus are involved in the regulation of both inhibitory avoidance and escape, those of the median raphe nucleus are primarily implicated in the former task; (2) facilitation of 5-HT1A- and 5-HT2A-mediated neurotransmission in the dorsal periaqueductal gray (dPAG) is likely to mediate the panicolytic drug action; (3) stimulation of 5-HT2C receptors in the basolateral amygdala increases anxiety and is implicated in the anxiogenesis caused by short-term administration of antidepressant drugs, and (4) 5-HT1A and the μ-opioid receptors work together in the dPAG to modulate escape or panic attacks. These last results point to the possible benefits of adjunctive opioid therapy for panic patients resistant to antidepressants that act on 5-HT neurotransmission. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Myristic Acid Produces Anxiolytic-Like Effects in Wistar Rats in the Elevated Plus Maze

    Science.gov (United States)

    García-Ríos, Rosa Isela; Cueto-Escobedo, Jonathan; Guillen-Ruiz, Gabriel; Bernal-Morales, Blandina

    2014-01-01

    A mixture of eight fatty acids (linoleic, palmitic, stearic, myristic, elaidic, lauric, oleic, and palmitoleic acids) at similar concentrations identified in human amniotic fluid produces anxiolytic-like effects comparable to diazepam in Wistar rats. However, individual effects of each fatty acid remain unexplored. In Wistar rats, we evaluated the separate action of each fatty acid at the corresponding concentrations previously found in human amniotic fluid on anxiety-like behaviour. Individual effects were compared with vehicle, an artificial mixture of the same eight fatty acids, and a reference anxiolytic drug (diazepam, 2 mg/kg). Myristic acid, the fatty acid mixture, and diazepam increased the time spent in the open arms of the elevated plus maze and reduced the anxiety index compared with vehicle, without altering general locomotor activity. The other fatty acids had no effect on anxiety-like behaviour, but oleic acid reduced locomotor activity. Additionally, myristic acid produced anxiolytic-like effects only when the concentration corresponded to the one identified in human amniotic fluid (30 𝜇g/mL) but did not alter locomotor activity. We conclude that of the eight fatty acids contained in the fatty acid mixture, only myristic acid produces anxiolytic-like effects when administered individually at a similar concentration detected in human amniotic fluid. PMID:25328885

  16. The differential hippocampal phosphoproteome of Apodemus sylvaticus paralleling spatial memory retrieval in the Barnes maze.

    Science.gov (United States)

    Li, Lin; Csaszar, Edina; Szodorai, Edit; Patil, Sudarshan; Pollak, Arnold; Lubec, Gert

    2014-05-01

    Protein phosphorylation is a well-known and well-documented mechanism in memory processes. Although a large series of protein kinases involved in memory processes have been reported, information on phosphoproteins is limited. It was therefore the aim of the study to determine a partial and differential phosphoproteome along with the corresponding network in hippocampus of a wild caught mouse strain with excellent performance in several paradigms of spatial memory. Apodemus sylvaticus mice were trained in the Barnes maze, a non-invasive test system for spatial memory and untrained mice served as controls. Animals were sacrificed 6h following memory retrieval, hippocampi were taken, proteins extracted and in-solution digestion was carried out with subsequent iTRAQ double labelling. Phosphopeptides were enriched by a TiO2-based method and semi-quantified using two fragmentation principles on the LTQ-orbitrap Velos. In hippocampi of trained animals phosphopeptide levels representing signalling, neuronal, synaptosomal, cytoskeletal and metabolism proteins were at least twofold reduced or increased. Furthermore, a network revealing a link to pathways of ubiquitination, the androgen receptor, small GTPase Rab5 and MAPK signaling as well as synucleins was constructed. This work is relevant for interpretation of previous work and the design of future studies on protein phosphorylation in spatial memory.

  17. Exercise prevents high-fat diet-induced impairment of flexible memory expression in the water maze and modulates adult hippocampal neurogenesis in mice.

    Science.gov (United States)

    Klein, C; Jonas, W; Iggena, D; Empl, L; Rivalan, M; Wiedmer, P; Spranger, J; Hellweg, R; Winter, Y; Steiner, B

    2016-05-01

    Obesity is currently one of the most serious threats to human health in the western civilization. A growing body of evidence suggests that obesity is associated with cognitive dysfunction. Physical exercise not only improves fitness but it has also been shown in human and animal studies to increase hippocampus-dependent learning and memory. High-fat diet (HFD)-induced obesity and physical exercise both modulate adult hippocampal neurogenesis. Adult neurogenesis has been demonstrated to play a role in hippocampus-dependent learning and memory, particularly flexible memory expression. Here, we investigated the effects of twelve weeks of HFD vs. control diet (CD) and voluntary physical activity (wheel running; -R) vs. inactivity (sedentary; -S) on hippocampal neurogenesis and spatial learning and flexible memory function in female C57Bl/6 mice assessed in the Morris water maze. HFD was initiated either in adolescent mice combined with long-term concurrent exercise (preventive approach) or in young adult mice with 14days of subsequent exercise (therapeutic approach). HFD resulted in impaired flexible memory expression only when initiated in adolescent (HFD-S) but not in young adult mice, which was successfully prevented by concurrent exercise (HFD-R). Histological analysis revealed a reduction of immature neurons in the hippocampus of the memory-impaired HFD-S mice of the preventive approach. Long-term physical exercise also led to accelerated spatial learning during the acquisition period, which was accompanied by increased numbers of newborn mature neurons (HFD-R and CD-R). Short-term exercise of 14days in the therapeutic group was not effective in improving spatial learning or memory. We show that (1) alterations in learning and flexible memory expression are accompanied by changes in the number of neuronal cells at different maturation stages; (2) these neuronal cells are in turn differently affected by HFD; (3) adolescent mice are specifically susceptible to the

  18. Cognitive ergonomics in virtual environments: development of an intuitive and appropriate input device for navigating in a virtual maze.

    Science.gov (United States)

    Stefani, Oliver; Mager, Ralph; Mueller-Spahn, Franz; Sulzenbacher, Hubert; Bekiaris, Evangelos; Wiederhold, Brenda K; Patel, Harshada; Bullinger, Alex H

    2005-09-01

    For patients suffering from mild cognitive impairments, the navigation through a virtual maze should be as intuitive and efficient as possible in order to minimize cognitive and physical strain. This paper discusses the appropriateness of interaction devices for being used for easy navigation tasks. Information gained from human centered evaluation was used to develop an intuitive and ergonomic interaction device. Two experiments examined the usability of tracked interaction devices. Usability problems with the devices are discussed. The findings from the experiments were translated into general design guidance, in addition to specific recommendations. A new device was designed on the basis of these recommendations and its usability was evaluated in a second experiment. The results were used to develop a lightweight interaction device for navigation in the virtual maze.

  19. Maze solving automatons for self-healing of open interconnects: Modular add-on for circuit boards

    Energy Technology Data Exchange (ETDEWEB)

    Nair, Aswathi; Raghunandan, Karthik; Yaswant, Vaddi; Sambandan, Sanjiv, E-mail: sanjiv@iap.iisc.ernet.in, E-mail: ssanjiv@isu.iisc.ernet.in [Department of Instrumentation and Applied Physics, Indian Institute of Science, Malleswaram, Bangalore 560012 (India); Pillai, Sreelal S. [Vikram Sarabhai Space Center, Indian Space Research Organization, Trivandrum 695022 (India)

    2015-03-23

    We present the circuit board integration of a self-healing mechanism to repair open faults. The electric field driven mechanism physically restores fractured interconnects in electronic circuits and has the ability to solve mazes. The repair is performed by conductive particles dispersed in an insulating fluid. We demonstrate the integration of the healing module onto printed circuit boards and the ability of maze solving. We model and perform experiments on the influence of the geometry of conductive particles as well as the terminal impedances of the route on the healing efficiency. The typical heal rate is 10 μm/s with healed route having mean resistance of 8 kΩ across a 200 micron gap and depending on the materials and concentrations used.

  20. Persistent atrial fibrillation is associated with inability to recover atrial contractility after MAZE IV surgery in rheumatic disease.

    Science.gov (United States)

    Tinetti, Matias; Costello, Ramiro; Cardenas, Cesar; Piazza, Antonio; Iglesias, Ricardo; Baranchuk, Adrian

    2012-08-01

    MAZE IV surgery is effective in restoring sinus rhythm (SR) and atrial contraction (AC) in patients with nonrheumatic persistent atrial fibrillation (AF). However, there is less information on its effectiveness to restore AC in patients with rheumatic disease. To assess the effectiveness of the MAZE IV surgery in restoring AC in patients with rheumatic disease and long persistent AF. Prospective, consecutive study in patients who underwent cardiovascular surgery and had long persistent AF in whom MAZE IV surgery was performed. The presence of AC was assessed by lateral mitral annulus tissue Doppler. A total of 75 patients were included. Mean age 60 years (±11.7); 27 men (36%). AF duration was 63 months (±34.1). Primary indication for surgery: rheumatic mitral stenosis 67 patients and mitral insufficiency eight patients. Mean left ventricular ejection fraction (LVEF) was 51.8% (±12.1) and mean left atrial area was 37 cm(2) (±10.3). After a mean follow-up of 28 months (±9.3), 69 patients remained alive and 59 were in SR. AC was detected in 37.3% (Group A) and absent in 62.7% (Group B). The mean difference between groups was the high prevalence of AF longer than 5 years in group B (P = 0.000001). There were no differences related to left atrial size, LVEF, and age. In patients with rheumatic disease, the absence of correlation between SR recovery and AC recovery post MAZE IV surgery is significant. A history of long persistent AF lasting more than 5 years was a strong predictor for the absence of AC. ©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.

  1. Behavioral effects of "vehicle" microinjected into the dorsal periaqueductal grey of rats tested in the elevated plus maze

    Directory of Open Access Journals (Sweden)

    Matheus M.G.

    1997-01-01

    Full Text Available To investigate the behavioral effects of different vehicles microinjected into the dorsal periaqueductal grey (DPAG of male Wistar rats, weighing 200-250 g, tested in the elevated plus maze, animals were implanted with cannulas aimed at this structure. One week after surgery the animals received microinjections into the DPAG of 0.9% (w/v saline, 10% (v/v dimethyl sulfoxide (DMSO, 2% (v/v Tween-80, 10% (v/v propylene glycol, or synthetic cerebrospinal fluid (CSF. Ten min after the injection (0.5 µl the animals (N = 8-13/group were submitted to the elevated plus maze test. DMSO significantly increased the number of entries into both the open and enclosed arms when compared to 0.9% saline (2.7 ± 0.8 and 8.7 ± 1.3 vs 0.8 ± 0.3 and 5.1 ± 0.9, respectively, Duncan test, P<0.05, and tended to increase enclosed arm entries as compared to 2% Tween-80 (8.7 ± 1.3 vs 5.7 ± 0.9, Duncan test, P<0.10. In a second experiment no difference in plus maze exploration was found between 0.9% saline- or sham-injected animals (N = 11-13/group. These results indicate that intra-DPAG injection of some commonly used vehicles such as DMSO, saline or Tween-80 affects the exploratory activity of rats exposed to the elevated plus maze in statistically different manners

  2. "Wagging the dog": How service delivery can lose its way in the procurement maze -- and could find it again

    CSIR Research Space (South Africa)

    Wall, K

    2012-09-01

    Full Text Available delivery can lose its way in the procurement maze -- and could find it again Kevin Wall, Ron Watermeyer and Graham Pirie Kevin Wall (CSIR); Ron Watermeyer (Soderlund and Schutte); Graham Pirie (Consulting Engineers South Africa (CESA... with the provisions of the Preferential Policy Framework Act, 2000 and points for quality scored out of maximum of 100 points. The points for the preference points system are added to the points for quality in terms of the weightings stipulated in the procurement...

  3. The GABAergic Anterior Paired Lateral Neurons Facilitate Olfactory Reversal Learning in "Drosophila"

    Science.gov (United States)

    Wu, Yanying; Ren, Qingzhong; Li, Hao; Guo, Aike

    2012-01-01

    Reversal learning has been widely used to probe the implementation of cognitive flexibility in the brain. Previous studies in monkeys identified an essential role of the orbitofrontal cortex (OFC) in reversal learning. However, the underlying circuits and molecular mechanisms are poorly understood. Here, we use the T-maze to investigate the neural…

  4. Coherent theta oscillations and reorganization of spike timing in the hippocampal-prefrontal network upon learning

    NARCIS (Netherlands)

    Benchenane, K.; Peyrache, A.; Khamassi, M.; Tierney, P.L.; Gioanni, Y.; Battaglia, F.P.; Wiener, S.I.

    2010-01-01

    To study the interplay between hippocampus and medial prefrontal cortex (Pfc) and its importance for learning and memory consolidation, we measured the coherence in theta oscillations between these two structures in rats learning new rules on a Y maze. Coherence peaked at the choice point, most stro

  5. Dynamic Changes in Acetylcholine Output in the Medial Striatum during Place Reversal Learning

    Science.gov (United States)

    Ragozzino, Michael E.; Choi, Daniel

    2004-01-01

    The present studies explored the role of the medial striatum in learning when task contingencies change. Experiment 1 examined whether the medial striatum is involved in place reversal learning. Testing occurred in a modified cross-maze across two consecutive sessions. Injections of the local anesthetic, bupivacaine, into the medial striatum, did…

  6. The GABAergic Anterior Paired Lateral Neurons Facilitate Olfactory Reversal Learning in "Drosophila"

    Science.gov (United States)

    Wu, Yanying; Ren, Qingzhong; Li, Hao; Guo, Aike

    2012-01-01

    Reversal learning has been widely used to probe the implementation of cognitive flexibility in the brain. Previous studies in monkeys identified an essential role of the orbitofrontal cortex (OFC) in reversal learning. However, the underlying circuits and molecular mechanisms are poorly understood. Here, we use the T-maze to investigate the neural…

  7. Anxiolytic effects of short- and long-term administration of cacao mass on rat elevated T-maze test.

    Science.gov (United States)

    Yamada, Takashi; Yamada, Yasushi; Okano, Yasuyo; Terashima, Takehiko; Yokogoshi, Hidehiko

    2009-12-01

    We demonstrated the effects of short- and long-term administration of cacao mass on anxiety in the elevated T-maze test, which is an animal model of anxiety. In the first study, we administered cacao mass (100 mg/100 g body weight) per os and immediately performed the elevated T-maze test. Short-term cacao mass significantly abolished delayed avoidance latency compared with the control but did not change escape latency. This result suggested that cacao mass administration reduced conditional fear-relating behavior. Short-term cacao mass administration did not affect the concentration of brain monoamines, emotion-related neurotransmitters such as norepinephrine, serotonin and dopamine, in the rat brain. In the next study, we fed a cacao mass-containing diet to rats for 2 weeks and performed the elevated T-maze test. Contrary to short-term administration, chronic consumption of cacao mass tended to increase avoidance latency and did not change escape latency. Brain serotonin concentration and its turnover were enhanced by chronic consumption of cacao mass. These results suggested that chronic consumption of cacao did not affect fear-related behavior but was involved in brain monoamine metabolism. In conclusion, we suggest that short-term cacao mass consumption showed an anxiolytic effect but chronic consumption did not.

  8. Harvard v. Canada: the myc mouse that still squeaks in the maze of biopatent law.

    Science.gov (United States)

    Deftos, L J

    2001-07-01

    The Canadian Supreme Court will soon make a decision about Harvard University's long-standing application for a Canadian patent on a mouse transgenic for the myc oncogene. That decision could reignite in North America the controversy that continues in Europe and elsewhere to surround the patenting of life forms. The tortuous steps in this 15-year patent maze are marked by the arguments about life patents that attended the U.S. Supreme Court's decision in Diamond v. Chakrabarty. This patent dispute about oil-digesting bacteria cracked open the door for animal patents in the United States and other countries, even though the legal arguments involved were based on patent applications for corn seeds and oysters, not mammals. The patent challenge to the Harvard mouse by the Canadian government now threatens to close this door in Canada. The arguments against life patents are commonly based on moral and religious grounds that regard the sanctity of life and oppose its commodification. The most compelling arguments for such patents are based on the benefits they deliver through commercial exploitation of inventions. The debate about patenting animals has been more heated outside North America and cacaphonic in the Third World. However, the Canadian debate could be amplified by the U.S. Supreme Court's recent entry on the biopatent stage through the side door of a new corn seed patent dispute. A narrow legal analysis by the Canadian Supreme Court would award the mouse patent to Harvard, while a policy analysis might support the government's challenge of the patent. Although the impact of the Harvard mouse patent process in Canada could be just a squeak, opponents of patenting life can mount the myc mouse to once again roar their opposition to animal patents. And the sound could resonate through the arguments about both biopatents and human cloning, with potentially important effects for academia, industry, and the public.

  9. A single center's experience with pacemaker implantation after the Cox maze procedure for atrial fibrillation.

    Science.gov (United States)

    Ad, Niv; Holmes, Sari D; Ali, Rabia; Pritchard, Graciela; Lamont, Deborah

    2017-07-01

    The Cox maze procedure (CM) is safe and effective for all atrial fibrillation (AF) types. A recent randomized trial found alarming rates of pacemaker implantation (PMI) during hospitalization after CM. The purpose of this study was to assess the rate of PMI and its impact on outcomes after CM. Incidence of PMI was captured for all CM patients (2005-2015; N = 739). Data were collected prospectively. Multivariable logistic regression was conducted to determine risk factors for PMI. Propensity score matching was conducted between concomitant CM patients and patients without surgical ablation since 2011. Fifty-two patients (7.0%) had in-hospital PMI after CM. Most common primary indication for PMI was sick sinus syndrome (67%), followed by complete heart block (23%) and sinus bradycardia (10%). The only risk factor for in-hospital PMI was type of procedure (P = .020). Patients with multiple valve procedures were at greatest risk (P = .004-.035). STS-defined perioperative outcomes were similar for patients with and without in-hospital PMI. Sinus rhythm off antiarrhythmic drugs were similar by PMI. After propensity score matching (n = 180 per group), in-hospital PMI was similar in CM patients and those without surgical ablation (5% vs 4%, P = .609). This study demonstrated lower incidence of PMI after CM procedures than recently reported. When indicated, PMI was not associated with increased short- or long-term morbidity or inferior freedom from atrial arrhythmia. Efforts to increase surgeon training with the CM procedure and postoperative management awareness are warranted to improve rhythm outcome and minimize adverse events and PMI. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  10. Flavonoids from Tilia americana with anxiolytic activity in plus-maze test.

    Science.gov (United States)

    Herrera-Ruiz, Maribel; Román-Ramos, Rubén; Zamilpa, Alejandro; Tortoriello, Jaime; Jiménez-Ferrer, J Enrique

    2008-07-23

    The aerial parts of Tilia americana var. mexicana (Schltdl) Hardin (Tiliaceae) have been widely used in Mexican traditional medicine to relieve sleeplessness, headache, and nervous excitement. The anxiolytic effect of four extracts and several flavonoid fractions from the bracts of Tilia americana subsp.mexicana, var. mexicana (Schltdl) Hardin or Tilia mexicana (Tiliaceae) was studied. Administration of 100mg/kg of n-hexane, ethyl acetate, and aqueous extracts to elevated plus-maze (EPM)-exposed mice displayed no anxiolytic effect; however, identical doses of methanol extract was able to increase the time percentage that mice spent in the EPM's open arms, as well as the percentage of crossings in the EPM's arms. The dose-response curve produced by methanol extract showed anxiolytic activity since 25mg/kg; animals showed no motor activity alteration in the open field test (OFT). Methanol extract was subjected to a bioassay-guided fractionation to obtain four ascendant polarity fractions (F1-F4) which were administrated at 100mg/kg. Data results indicate that F1 displayed the main anxiolytic effect. The purification of F1 produced a rich flavonoid anxiolytic mixture (F1C). This fraction was purified by RP-18 open chromatographic column to obtain four polar descent fractions: F1C(1), F1C(2), F1C(3), and F1C(4), respectively. Tiliroside was the major ingredient from the active fraction. High performance liquid chromatography analysis indicated that F1C was constituted principally of tiliroside, quercetin, quercitrin, kaempherol, and their glycosides. These results supported the use of Tilia americana in Mexican traditional medicine as well as the anxiolytic effect of a rich flavonoid fraction without affect motor activity.

  11. Androgen insensitive male rats display increased anxiety-like behavior on the elevated plus maze.

    Science.gov (United States)

    Hamson, Dwayne K; Jones, Bryan A; Csupity, Attila S; Ali, Faezah M; Watson, Neil V

    2014-02-01

    Male rats carrying the testicular feminization mutation (Tfm-affected males) are insensitive to androgens, resulting in a female-typical peripheral phenotype despite possession of inguinal testes that are androgen secretory. Androgen-dependent neural and behavioral processes may likewise show atypical sexual differentiation. Interestingly, these mutant rats display elevated serum corticosterone, suggesting a chronic anxiety phenotype and dysregulated hypothalamic-pituitary-adrenal axis. In order to understand if elevated anxiety-like behavior is a possible mediating variable affecting the display of certain androgen-dependent behaviors, we compared the performance of Tfm-affected males to wild type males and females in the elevated plus maze (EPM). Two well-established indicators of anxiety-like behavior in the EPM were analyzed: total percentage of time spent on the open arms, and the percentage of open arm entries. We also analyzed the total number of open arm entries. Interestingly, Tfm-affected males spent less percentage of time on the open arms than both males and females, suggesting increased anxiety-like behavior. Percentage of open arm entries and the total number of arm entries was comparable between the groups, indicating that the observed decrease in the percentage of time spent on the open arms was not due to a global reduction in exploratory behavior. These data, in contrast to earlier reports, thus implicate androgen receptor-mediated functions in the expression of anxiety behaviors in male rats. Given that anxiety is widely reported as a precipitating factor in depression, studying the role of the androgen receptor in anxiety may give insights into the pathogenesis of major depressive disorder.

  12. Effects of acute and chronic nicotine on elevated plus maze in mice: involvement of calcium channels.

    Science.gov (United States)

    Biala, Grazyna; Budzynska, Barbara

    2006-05-30

    The current experiments examined the anxiety-related effects of acute and repeated nicotine administration using the elevated plus maze test in mice. Nicotine (0.1 mg/kg s.c., 5 and 30 min after injection; 0.5 mg/kg, s.c., 5 min after injection) had an anxiogenic effect, shown by specific decreases in the percentage of time spent on the open arms and in the percentage of open arm entries. Tolerance developed to this anxiogenic action after 6 days of daily nicotine administration (0.1 mg/kg, s.c.). Five minutes after the seventh injection, an anxiolytic effect was observed, i.e., specific increases in the percentage of time spent on the open arms and in the percentage of open arm entries. L-type voltage-dependent calcium channel antagonists nimodipine (5 and 10 mg/kg, i.p.), flunarizine (5 and 10 mg/kg, i.p.), verapamil (5, 10, 20 mg/kg) and diltiazem (5, 10, 20 mg/kg, i.p.) were also injected prior to an acute low dose of nicotine or to each injection of chronic nicotine. Our results revealed that calcium channel blockers dose-dependently attenuated both an anxiogenic effect of nicotine as well as the development of tolerance to this effect. Our results suggest that neural calcium-dependent mechanisms are involved in the anxiety-related responses to acute and chronic nicotine injection that may ultimately lead to addiction and smoking relapse in human smokers.

  13. Midazolam-ketamine dual therapy stops cholinergic status epilepticus and reduces Morris water maze deficits.

    Science.gov (United States)

    Niquet, Jerome; Baldwin, Roger; Norman, Keith; Suchomelova, Lucie; Lumley, Lucille; Wasterlain, Claude G

    2016-09-01

    Pharmacoresistance remains an unsolved therapeutic challenge in status epilepticus (SE) and in cholinergic SE induced by nerve agent intoxication. SE triggers a rapid internalization of synaptic γ-aminobutyric acid A (GABAA ) receptors and externalization of N-methyl-d-aspartate (NMDA) receptors that may explain the loss of potency of standard antiepileptic drugs (AEDs). We hypothesized that a drug combination aimed at correcting the consequences of receptor trafficking would reduce SE severity and its long-term consequences. A severe model of SE was induced in adult Sprague-Dawley rats with a high dose of lithium and pilocarpine. The GABAA receptor agonist midazolam, the NMDA receptor antagonist ketamine, and/or the AED valproate were injected 40 min after SE onset in combination or as monotherapy. Measures of SE severity were the primary outcome. Secondary outcomes were acute neuronal injury, spontaneous recurrent seizures (SRS), and Morris water maze (MWM) deficits. Midazolam-ketamine dual therapy was more efficient than double-dose midazolam or ketamine monotherapy or than valproate-midazolam or valproate-ketamine dual therapy in reducing several parameters of SE severity, suggesting a synergistic mechanism. In addition, midazolam-ketamine dual therapy reduced SE-induced acute neuronal injury, epileptogenesis, and MWM deficits. This study showed that a treatment aimed at correcting maladaptive GABAA receptor and NMDA receptor trafficking can stop SE and reduce its long-term consequences. Early midazolam-ketamine dual therapy may be superior to monotherapy in the treatment of benzodiazepine-refractory SE. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  14. Molecular mechanisms for the destabilization and restabilization of reactivated spatial memory in the Morris water maze

    Directory of Open Access Journals (Sweden)

    Kim Ryang

    2011-02-01

    Full Text Available Abstract Background Memory retrieval is not a passive process. Recent studies have shown that reactivated memory is destabilized and then restabilized through gene expression-dependent reconsolidation. Molecular studies on the regulation of memory stability after retrieval have focused almost exclusively on fear memory, especially on the restabilization process of the reactivated fear memory. We previously showed that, similarly with fear memories, reactivated spatial memory undergoes reconsolidation in the Morris water maze. However, the underlying molecular mechanisms by which reactivated spatial memory is destabilized and restabilized remain poorly understood. In this study, we investigated the molecular mechanism that regulates the stability of the reactivated spatial memory. Results We first showed that pharmacological inactivation of the N-methyl-D-aspartate glutamate receptor (NMDAR in the hippocampus or genetic inhibition of cAMP-responsible element binding protein (CREB-mediated transcription disrupted reactivated spatial memory. Finally, we showed that pharmacological inhibition of cannabinoid receptor 1 (CB1 and L-type voltage gated calcium channels (LVGCCs in the hippocampus blocked the disruption of the reactivated spatial memory by the inhibition of protein synthesis. Conclusions Our findings indicated that the reactivated spatial memory is destabilized through the activation of CB1 and LVGCCs and then restabilized through the activation of NMDAR- and CREB-mediated transcription. We also suggest that the reactivated spatial memory undergoes destabilization and restabilization in the hippocampus, through similar molecular processes as those for reactivated contextual fear memories, which require CB1 and LVGCCs for destabilization and NMDAR and CREB for restabilization.

  15. 筛选训练对Morris水迷宫测试成绩的影响%Effect of Screening and Training on the Morris Water Maze Memory Performance of Mice

    Institute of Scientific and Technical Information of China (English)

    钱晓路; 孙蓉

    2013-01-01

    Objective To investigate the effect of the screening and training on Morris water maze memory performance of mice in order to offer the references and research ideas for impaired memory model. Methods Normal mice were divided into different groups such as the normal group with screening and training, model group with screening and training, normal group except screening and training, model group except screening and training and Positive drug control group. The screening and training group had Morris water maze test before the formal experiment to make sure every mice could find the platform in the provision of time. The ability of learning and memory were observed using Morris water maze. Results Screening and training of mice had a significant impact on the Morris water maze test, it could significantly shorten the latency and improve the ability of learning and memory in mice. Conclusion For the Morris water maze performance, the dementia model induced by scopolamine should be screened and trained before the formal experiment, so that the accuracy of the results could be greatly improved.%目的 对东莨菪碱致痴呆模型进行Morris水迷宫实验,观察比较筛选训练对小鼠Morris水迷宫学习记忆的影响,为完善与优化东莨菪碱致记忆获得性障碍痴呆模型提供方法学参考.方法 新购进昆明种小鼠,随机分为筛选训练正常组、筛选训练模型组、不筛选训练正常组、不筛选训练模型组.筛选训练各组正式实验前先进行水迷宫筛选训练,将筛选训练不合格的小鼠剔除出实验,确保每只小鼠均能在规定时间内找到平台;不训练各组购进后直接与筛选训练组同时进行Morris水迷宫实验,观察其对学习记忆测试的影响.结果 动物筛选训练对Morris水迷宫实验具有显著性影响,可以显著性的缩短小鼠的潜伏期,提高小鼠的学习记忆能力.结论 实验前进行水迷宫筛选训练,可大大提高Morris水迷宫实验对

  16. Differential Endocannabinoid Regulation of Extinction in Appetitive and Aversive Barnes Maze Tasks

    Science.gov (United States)

    Harloe, John P.; Thorpe, Andrew J.; Lichtman, Aron H.

    2008-01-01

    CB[subscript 1] receptor-compromised animals show profound deficits in extinguishing learned behavior from aversive conditioning tasks, but display normal extinction learning in appetitive operant tasks. However, it is difficult to discern whether the differential involvement of the endogenous cannabinoid system on extinction results from the…

  17. Improving Students' English Pronunciation Ability through Go Fish Game and Maze Game

    Science.gov (United States)

    Nurhayati, Dwi Astuti Wahyu

    2015-01-01

    The problem highlighted in this research is the low pronunciation ability of Kindergarten students in Al-Irsyad Madiun that is caused by (1) the uninteresting activities in learning English; (2) the students' difficulties of English pronunciation; (3) the students' low motivation in learning. The theoretical review includes the young learners…

  18. A Contest-Oriented Project for Learning Intelligent Mobile Robots

    Science.gov (United States)

    Huang, Hsin-Hsiung; Su, Juing-Huei; Lee, Chyi-Shyong

    2013-01-01

    A contest-oriented project for undergraduate students to learn implementation skills and theories related to intelligent mobile robots is presented in this paper. The project, related to Micromouse, Robotrace (Robotrace is the title of Taiwanese and Japanese robot races), and line-maze contests was developed by the embedded control system research…

  19. Looking ahead? Computerized maze task performance by chimpanzees (Pan troglodytes), rhesus monkeys (Macaca mulatta), capuchin monkeys (Cebus apella), and human children (Homo sapiens).

    Science.gov (United States)

    Beran, Michael J; Parrish, Audrey E; Futch, Sara E; Evans, Theodore A; Perdue, Bonnie M

    2015-05-01

    Human and nonhuman primates are not mentally constrained to the present. They can remember the past and-at least to an extent-anticipate the future. Anticipation of the future ranges from long-term prospection such as planning for retirement to more short-term future-oriented cognition such as planning a route through a maze. Here we tested a great ape species (chimpanzees), an Old World monkey species (rhesus macaques), a New World monkey species (capuchin monkeys), and human children on a computerized maze task. All subjects had to move a cursor through a maze to reach a goal at the bottom of the screen. For best performance on the task, subjects had to "plan ahead" to the end of the maze to move the cursor in the correct direction, avoid traps, and reverse directions if necessary. Mazes varied in difficulty. Chimpanzees were better than both monkey species, and monkeys showed a particular deficit when moving away from the goal or changing directions was required. Children showed a similar pattern to monkeys regarding the effects of reversals and moves away from the goal, but their overall performance in terms of correct maze completion was similar to the chimpanzees. The results highlight similarities as well as differences in planning across species and the role that inhibitory control may play in future-oriented cognition in primates.

  20. Running enhances neurogenesis, learning, and long-term potentiation in mice

    Science.gov (United States)

    van Praag, Henriette; Christie, Brian R.; Sejnowski, Terrence J.; Gage, Fred H.

    1999-01-01

    Running increases neurogenesis in the dentate gyrus of the hippocampus, a brain structure that is important for memory function. Consequently, spatial learning and long-term potentiation (LTP) were tested in groups of mice housed either with a running wheel (runners) or under standard conditions (controls). Mice were injected with bromodeoxyuridine to label dividing cells and trained in the Morris water maze. LTP was studied in the dentate gyrus and area CA1 in hippocampal slices from these mice. Running improved water maze performance, increased bromodeoxyuridine-positive cell numbers, and selectively enhanced dentate gyrus LTP. Our results indicate that physical activity can regulate hippocampal neurogenesis, synaptic plasticity, and learning. PMID:10557337

  1. 33 CFR 110.50c - Mumford Cove, Groton, Conn.

    Science.gov (United States)

    2010-07-01

    .... Beginning at a point on the easterly shore of Mumford Cove at latitude 41°19′36″, longitude 72°01′06... a point on the easterly shore of Mumford Cove at latitude 41°19′15″, longitude 72°00′54″; thence...

  2. Tiger salamanders' (Ambystoma tigrinum) response learning and usage of visual cues.

    Science.gov (United States)

    Kundey, Shannon M A; Millar, Roberto; McPherson, Justin; Gonzalez, Maya; Fitz, Aleyna; Allen, Chadbourne

    2016-05-01

    We explored tiger salamanders' (Ambystoma tigrinum) learning to execute a response within a maze as proximal visual cue conditions varied. In Experiment 1, salamanders learned to turn consistently in a T-maze for reinforcement before the maze was rotated. All learned the initial task and executed the trained turn during test, suggesting that they learned to demonstrate the reinforced response during training and continued to perform it during test. In a second experiment utilizing a similar procedure, two visual cues were placed consistently at the maze junction. Salamanders were reinforced for turning towards one cue. Cue placement was reversed during test. All learned the initial task, but executed the trained turn rather than turning towards the visual cue during test, evidencing response learning. In Experiment 3, we investigated whether a compound visual cue could control salamanders' behaviour when it was the only cue predictive of reinforcement in a cross-maze by varying start position and cue placement. All learned to turn in the direction indicated by the compound visual cue, indicating that visual cues can come to control their behaviour. Following training, testing revealed that salamanders attended to stimuli foreground over background features. Overall, these results suggest that salamanders learn to execute responses over learning to use visual cues but can use visual cues if required. Our success with this paradigm offers the potential in future studies to explore salamanders' cognition further, as well as to shed light on how features of the tiger salamanders' life history (e.g. hibernation and metamorphosis) impact cognition.

  3. The transfer from survey (map-like to route representations into Virtual Reality Mazes: effect of age and cerebral lesion

    Directory of Open Access Journals (Sweden)

    Stampatori Chiara

    2011-01-01

    Full Text Available Abstract Background To go from one place to another, we routinely generate internal representations of surrounding spaces, which can include egocentric (body-centred and allocentric (world-centred coordinates, combined into route and survey representations. Recent studies have shown how both egocentric and allocentric representations exist in parallel and are joined to support behaviour according to the task. Our study investigated the transfer from survey (map-like to route representations in healthy and brain-damaged subjects. The aim was two-fold: first, to understand how this ability could change with age in a sample of healthy participants, aged from 40 to 71 years old; second, to investigate how it is affected after a brain lesion in a 8 patients' sample, with reference to specific neuropsychological frames. Methods Participants were first required to perform the paper and pencil version of eight mazes, then to translate the map-like paths into egocentric routes, in order to find the right way into equivalent Virtual Reality (VR mazes. Patients also underwent a comprehensive neuropsychological evaluation, including a specific investigation of some topographical orientation components. Results As regards the healthy sample, we found age-related deterioration in VR task performance. While education level and gender were not found to be related to performance, global cognitive level (Mini Mental State Examination, previous experience with computer and fluidity of navigation into the VR appeared to influence VR task results. Considering the clinical sample, there was a difficulty in performing the VR Maze task; executive functions and visuo-spatial abilities deficits appeared to be more relevant for predicting patients' results. Conclusions Our study suggests the importance of developing tools aimed at investigating the survey to route transfer ability in both healthy elderly and clinical samples, since this skill seems high cognitive

  4. Effect of Argyreia speciosa extract on learning and memory paradigms in mice

    Directory of Open Access Journals (Sweden)

    N S Vyawahare

    2009-01-01

    Full Text Available The objective of the present study was to investigate the effect of hydroalcoholic extract of Argyreia speciosa (AS on learning and memory paradigms in mice. Radial arm maze and morris water maze were the screening tests used to assess the activity of the extract. Piracetam served as a reference standard. The mice pretreated with AS 200 or AS 400 mg/kg or Piracetam (150mg/kg showed a decrease in number of days required to make the mice learned, time taken to find food by the learned mice in radial arm maze. In morris water maze, the mice treated with the above mentioned doses showed a significant reduction in the number of days required to make the mice learned, escape latency of learned mice and number of circles completed before it escapes on to the platform. The results suggest facilitation of spatial learning and memory processes and thereby validated its traditional claim of being tonic in dullness of intellect.

  5. A novel heterocyclic compound CE-104 enhances spatial working memory in the radial arm maze in rats and modulates the dopaminergic system

    Directory of Open Access Journals (Sweden)

    Yogesh D Aher

    2016-02-01

    Full Text Available Various psychostimulants targeting monoamine neurotransmitter transporters (MAT have been shown to rescue cognition in patients with neurological disorders and improve cognitive abilities in healthy subjects at low doses. Here, we examined the effects upon cognition of a chemically synthetized novel MAT inhibiting compound 2-(benzhydrylsulfinylmethyl-4-methylthiazole (named as CE-104. The efficacy of CE-104 in blocking MAT (DAT – dopamine transporter, SERT – serotonin transporter and NET – norepinephrine transporter was determined using in vitro neurotransmitter uptake assay. The effect of the drug at low doses (1 and 10mg/kg on spatial memory was studied in male rats in the radial arm maze (RAM. Furthermore, the dopamine receptor and transporter complex levels of frontal cortex (FC tissue of trained and untrained animals treated either with the drug or vehicle were quantified on blue native PAGE (BN-PAGE. The drug inhibited dopamine (IC50: 27.88µM and norepinephrine uptake (IC50: 160.40µM, but had a negligible effect on SERT. In the RAM, both drug-dose groups improved spatial working memory during the performance phase of RAM as compared to vehicle. BN-PAGE western blot quantification of dopamine receptor and transporter complexes revealed that D1, D2, D3 and DAT complexes were modulated due to training and by drug effects. The drug’s ability to block DAT and its influence on dopamine transporter and receptor complex levels in the FC is proposed as a possible mechanism for the observed learning and memory enhancement in the RAM.

  6. Decreased hippocampal homoarginine and increased nitric oxide and nitric oxide synthase levels in rats parallel training in a radial arm maze.

    Science.gov (United States)

    Sase, Ajinkya; Nawaratna, Gayan; Hu, Shengdi; Wu, Guoyao; Lubec, Gert

    2016-09-01

    L-homoarginine (hArg) is derived from enzymatic guanidination of lysine. It was demonstrated that hArg is a substrate for nitric oxide (NO) synthesis, blocks lysine transport and inhibits the uptake of arginine into synaptosomes and modulates GABA responses ex vivo. As there is limited information on its physiological roles in the brain, the aim of the study was to show whether hippocampal or frontal lobe (FL) hArg is paralleling training in the radial arm maze (RAM) or NO formation. Hippocampi and FL of male Sprague-Dawley rats were taken from trained or yoked in a RAM. Then hArg and metabolites, NO and NO synthase (NOS) were determined by standard methods. The animals learned the task in the RAM showing significant reduction of working memory errors. hArg showed decreased levels in both brain regions of trained animals as compared to yoked animals. Nitrate plus nitrite (NOx) concentrations and NOS activity were significantly increased in hippocampi, F(1,36) = 170.5; P ≤ 0.0001 and FL, F(1,36) = 74.67; P ≤ 0.0001 of trained animals as compared to yoked animals. Levels of hArg were negatively correlated with NOx in hippocampus (r = -0.6355; P = 0.0483) but not in FL and with lysine in the FL (r = -0.6650; P = 0.0358). NOx levels were positively correlated with NOS in both the hippocampus (r = 0.7474; P = 0.0129) and FL (r = 0.9563; P ≤  0.0001). These novel findings indicate that hArg is linked to NO formation in hippocampus but not in FL and is paralleling spatial memory in the RAM.

  7. The memory stages of a spatial Y-maze task are not affected by a low dose of ketamine/midazolam.

    Science.gov (United States)

    Valentim, Ana M; Ribeiro, Patrícia O; Olsson, I Anna S; Antunes, Luís M

    2013-07-15

    Anesthetics, such as the ketamine/midazolam combination, are used in research with animals and in human clinical practice; thus, it is essential to clarify the potential effects of these anesthetics on memory. This study aimed to evaluate how a low dose of the ketamine/midazolam combination affects the acquisition, consolidation, or recall of a spatial memory task. Thirty-three adult male C57BL/6 mice were divided into four treatment groups: unanesthetized control animals and three groups of animals treated with 40 mg/kg of ketamine and 10mg/kg of midazolam administered in a single intraperitoneal injection. The different treatment groups received the same anesthetic dose at different time points, to study the acquisition, consolidation, and recall of spatial memory in the Y-maze task. The percentage of correct choices was measured. Six mice were killed 4 days and 12 days after anesthesia for histopathological analyses. There were no differences between treatment and control groups regarding the acquisition of spatial memory, measured as the slope of the learning curve, or in the percentage of correct choices in the consolidation or recall periods of the task. Similarly, no differences were detected between groups regarding the number of cells per square millimeter in the visual and retrosplenial cortex, in the dentate gyrus, and in the CA1 and CA3 regions of the hippocampus. Hence, a low dose of the ketamine/midazolam combination did not impair memory processes or brain integrity in adult mice, suggesting that this combination is unlikely to cause cognitive complications.

  8. Corticosterone infused into the dorsal striatum selectively enhances memory consolidation of cued water-maze training

    NARCIS (Netherlands)

    Quirarte, Gina L.; Sofia Ledesma de la Teja, I.; Casillas, Miriam; Serafin, Norma; Prado-Alcala, Roberto A.; Roozendaal, Benno

    2009-01-01

    Glucocorticoid hormones enhance memory consolidation of hippocampus-dependent spatial/contextual learning, but little is known about their possible influence on the consolidation of procedural/implicit memory. Therefore, in this study we examined the effect of corticosterone (2, 5, or 10 ng) infused

  9. Corticosterone infused into the dorsal striatum selectively enhances memory consolidation of cued water-maze training

    NARCIS (Netherlands)

    Quirarte, Gina L.; Sofia Ledesma de la Teja, I.; Casillas, Miriam; Serafin, Norma; Prado-Alcala, Roberto A.; Roozendaal, Benno

    2009-01-01

    Glucocorticoid hormones enhance memory consolidation of hippocampus-dependent spatial/contextual learning, but little is known about their possible influence on the consolidation of procedural/implicit memory. Therefore, in this study we examined the effect of corticosterone (2, 5, or 10 ng) infused

  10. Dorsal periaqueductal gray stimulation facilitates anxiety-, but not panic-related, defensive responses in rats tested in the elevated T-maze

    Energy Technology Data Exchange (ETDEWEB)

    Camplesi, M. Jr. [Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO (Brazil); Bortoli, V.C. de [Departamento de Ciências da Saúde, Centro Universitário Norte do Espírito Santo, Universidade Federal do Espírito Santo, São Mateus, ES (Brazil); Paula Soares, V. de [Departamento de Biofísica e Farmacologia, Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Nogueira, R.L. [Laboratório de Psicologia Comparada, Universidade Estácio de Sá, Rio de Janeiro, RJ (Brazil); Zangrossi, H. Jr. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2012-08-03

    The escape response to electrical or chemical stimulation of the dorsal periaqueductal gray matter (DPAG) has been associated with panic attacks. In order to explore the validity of the DPAG stimulation model for the study of panic disorder, we determined if the aversive consequences of the electrical or chemical stimulation of this midbrain area can be detected subsequently in the elevated T-maze. This animal model, derived from the elevated plus-maze, permits the measurement in the same rat of a generalized anxiety- and a panic-related defensive response, i.e., inhibitory avoidance and escape, respectively. Facilitation of inhibitory avoidance, suggesting an anxiogenic effect, was detected in male Wistar rats (200-220 g) tested in the elevated T-maze 30 min after DPAG electrical stimulation (current generated by a sine-wave stimulator, frequency at 60 Hz) or after local microinjection of the GABA{sub A} receptor antagonist bicuculline (5 pmol). Previous electrical (5, 15, 30 min, or 24 h before testing) or chemical stimulation of this midbrain area did not affect escape performance in the elevated T-maze or locomotion in an open-field. No change in the two behavioral tasks measured by the elevated T-maze was observed after repetitive (3 trials) electrical stimulation of the DPAG. The results indicate that activation of the DPAG caused a short-lived, but selective, increase in defensive behaviors associated with generalized anxiety.

  11. Amphetamine-induced perseverative behavior in a radial arm maze following DSP4 or 6-OHDA pretreatment.

    Science.gov (United States)

    Bruto, V; Beauchamp, C; Zacharko, R M; Anisman, H

    1984-01-01

    Mice permitted to explore an 8-arm radial maze tended to visit those arms least recently entered. Treatment with D-amphetamine engendered a perseverative tendency, wherein mice repeatedly visited two arms of the maze. Administration of the norepinephrine (NE) neurotoxin, N-2-chloroethyl-N-ethyl-2-bromo-benzylamine (DSP4), appreciably reduced NE in the hippocampus and cortex, moderately reduced NE in the locus coeruleus, and had only a small effect on hypothalamic NE. The DSP4 treatment resulted in a decrease of locomotor activity among amphetamine-treated mice, coupled with an increase of stereotyped response patterns. Although the NE depletion did not affect the pattern of exploration that mice ordinarily displayed, DSP4 appreciably increased the perseverative tendency provoked by amphetamine. Reduction of dopamine (DA) and NE by intraventricular administration of the catecholamine neurotoxin, 6-hydroxydopamine (6-OHDA), antagonized the effects of amphetamine, such that the frequency of alternation responses was increased and the proportion of perseverative responses was reduced. The effectiveness of the 6-OHDA treatment in antagonizing the amphetamine-induced perseveration was not reduced among mice that were pretreated with desmethylimipramine, which resulted in partial prevention of the NE reduction by 6-OHDA administration. It is suggested that DA neuronal activity contributes to the amphetamine -provoked perseveration , whereas NE stimulation modifies the perseverative tendency by influencing exploration or habituation.

  12. Anxiogenic-like effect of acute and chronic fluoxetine on rats tested on the elevated plus-maze

    Directory of Open Access Journals (Sweden)

    M.T.A. Silva

    1999-03-01

    Full Text Available The selective serotonin reuptake inhibitor fluoxetine (FLX is widely prescribed for depression and anxiety-related disorders. On the other hand, enhanced serotonergic transmission is known to be classically related to anxiety. In this study, the effects of acute (5.0 mg/kg and chronic (5.0 mg/kg, 22 days FLX were investigated in both food-deprived and non-deprived rats tested in the elevated plus-maze. Significant main effects of the three factors (drug, food condition and administration regimen were observed, but no interaction between them. The administration of either acute or chronic FLX resulted in an anxiogenic effect, as detected by a significant reduction in the percentage of time spent in the open arms and in the percentage of open arm entries. Food deprivation yielded an anxiolytic-like profile, probably related to changes in locomotor activity. The administration regimen resulted in an anxiolytic profile in chronically treated rats, as would be expected after 22 days of regular handling. The anxiogenic action of acute FLX is consistent with both its neurochemical and clinical profile. The discrepancy between the anxiogenic profile of chronic FLX and its therapeutic uses is discussed in terms of possible differences between the type of anxiety that is measured in the plus-maze and the types of human anxiety that are alleviated by fluoxetine.

  13. Gantry orientation effect on the neutron and capture gamma ray dose equivalent at the maze entrance door in radiation therapy

    Directory of Open Access Journals (Sweden)

    Ghiasi Hosein

    2012-01-01

    Full Text Available In the present study, the effect of gantry orientation on the photoneutron and capture gamma dose calculations for maze entrance door was evaluated. A typical radiation therapy room made of ordinary concrete was simulated using MCNPX Monte Carlo code. Gantry rotation was simulated at eight different angles around the isocenter. Both neutron and capture gamma dose vary considerably with gantry angle. The ratios of the maximum to the minimum values for neutron and capture gamma dose equivalents were 1.9 and 1.4, respectively. On the other hand, comparison of the Monte Carlo calculated mean value over all orientations with Monte Carlo calculated neutron and gamma dose showed that the Wu-McGinley method differed by 5% and 2%, respectively. However, for more conservative shielding calculations, factors of 1.6 and 1.3 should be applied to the calculated neutron and capture gamma doses at downward irradiation. Finally, it can be concluded that the gantry angle influences neutron and capture gamma dose at the maze entrance door and it should be taken into account in shielding considerations.

  14. Histaminergic H1 receptors mediate L-histidine-induced anxiety in elevated plus-maze test in mice.

    Science.gov (United States)

    Kumar, Kuchibhotla Vijaya; Krishna, Devarakonda Rama; Palit, Gautam

    2007-05-01

    The central histaminergic system is reported to mediate behavioural, hormonal and physiological homeostasis of living organisms. Recent reports indicate its prominent role in various neurobehavioural disorders such as depression and psychosis. This study evaluated the effect of activation of the central histaminergic system in anxiety-like conditions, using the elevated plus-maze test in mice, and elucidated the role of different histaminergic receptors mediating such effects. Peripheral administration of L-histidine (L-His), in a dose-dependent manner, significantly decreased the exploration time in open arms and number of entries into open arms without modifying the number of entries into closed arms of the elevated plus-maze, indicating anxiogenesis. Further, such effects of central histamine were significantly attenuated, in a dose-dependent manner, by pretreatment with pyrilamine (H1 receptor antagonist). Pretreatment with either zolantidine (H2 receptor antagonist) or thioperamide (H3 receptor antagonist), however, failed to attenuate the L-His-induced anxiogenesis. Our results indicate that anxiogenic effects of central histaminergic system appear to be mediated prominently by activation of H1 receptors.

  15. Late Results of Cox Maze III Procedure in Patients with Atrial Fibrillation Associated with Structural Heart Disease.

    Science.gov (United States)

    Gomes, Gustavo Gir; Gali, Wagner Luis; Sarabanda, Alvaro Valentim Lima; Cunha, Claudio Ribeiro da; Kessler, Iruena Moraes; Atik, Fernando Antibas

    2017-07-01

    Cox-Maze III procedure is one of the surgical techniques used in the surgical treatment of atrial fibrillation (AF). To determine late results of Cox-Maze III in terms of maintenance of sinus rhythm, and mortality and stroke rates. Between January 2006 and January 2013, 93 patients were submitted to the cut-and-sew Cox-Maze III procedure in combination with structural heart disease repair. Heart rhythm was determined by 24-hour Holter monitoring. Procedural success rates were determined by longitudinal methods and recurrence predictors by multivariate Cox regression models. Thirteen patients that obtained hospital discharge alive were excluded due to lost follow-up. The remaining 80 patients were aged 49.9 ± 12 years and 47 (58.7%) of them were female. Involvement of mitral valve and rheumatic heart disease were found in 67 (83.7%) and 63 (78.7%) patients, respectively. Seventy patients (87.5%) had persistent or long-standing persistent AF. Mean follow-up with Holter monitoring was 27.5 months. There were no hospital deaths. Sinus rhythm maintenance rates were 88%, 85.1% and 80.6% at 6 months, 24 months and 36 months, respectively. Predictors of late recurrence of AF were female gender (HR 3.52; 95% CI 1.21-10.25; p = 0.02), coronary artery disease (HR 4.73 95% CI 1.37-16.36; p = 0.01) and greater left atrium diameter (HR 1.05; 95% CI 1.01-1.09; p = 0.02). Actuarial survival was 98.5% at 12, 24 and 48 months and actuarial freedom from stroke was 100%, 100% and 97.5% in the same time frames. The Cox-Maze III procedure, in our experience, is efficacious for sinus rhythm maintenance, with very low late mortality and stroke rates. A operação de Cox-Maze III é uma das variantes técnicas no tratamento cirúrgico da fibrilação atrial (FA). Estudar os resultados tardios da operação de Cox-Maze III, quanto à eficácia na manutenção de ritmo sinusal e taxas de mortalidade e acidente vascular cerebral (AVC). Entre janeiro de 2006 a janeiro de 2013, 93 pacientes

  16. Dopamine D1 and D2 receptor ligands modulate the behaviour of mice in the elevated plus-maze.

    Science.gov (United States)

    Rodgers, R J; Nikulina, E M; Cole, J C

    1994-12-01

    To further our understanding of the potential role of dopamine in mechanisms of anxiety, the effects of four dopamine receptor ligands were examined in an ethological version of the murine elevated plus-maze test. The D1 receptor partial agonist, SKF 38393 (2.5-20.0 mg/kg), had minimal behavioural activity in this test, whereas the selective D1 receptor antagonist, SCH 23390 (0.025-0.2 mg/kg), had dose-dependent but behaviourally nonspecific effects. Quinpirole (0.0625-0.5 mg/kg), a D2 receptor agonist, had no effects at low doses but severely disrupted locomotion and exploration at the highest doses tested. In marked contrast to the lack of effect or nonspecific effects seen with the other ligands tested, the D2 receptor antagonist, sulpiride (2.5-20.0 mg/kg), produced an unambiguous anxiolytic-like profile under present test conditions. Although none of the doses tested adversely affected general activity, clear antianxiety effects were observed on both traditional and novel (i.e., risk assessment) behavioural measures. Data are discussed in relation to the relative importance of D1 and D2 receptor mechanisms in plus-maze anxiety, and the need to further assess D2 involvement through the use of more selective compounds.

  17. Individual housing and handling procedures modify anxiety levels of Tg2576 mice assessed in the zero maze test.

    Science.gov (United States)

    Heredia, Luis; Torrente, Margarita; Domingo, José L; Colomina, María T

    2012-09-10

    The zero maze is an unconditioned anxiety test for mice, in which a number of environmental variables can modify the anxiety levels of the animals. In the present study, we have assessed how individual housing, handling procedure and interaction between individual housing and handling procedure affect the baseline anxiety of mice. Thirty-seven wild type mice and eighteen Tg2576 mice were used (obtained from crossing APPSWE hemizygous male C57BL6/SJL background with C57BL6/SJL female). Wild type mice were randomly assigned to four experimental groups: 1) group housed and unhandled, 2) group housed but handled, 3) individually housed, unhandled, and 4) individually housed and handled. In turn, Tg2576 mice were randomly assigned to two experimental groups: 1) individually housed, unhandled, and 2) individually housed and handled. The results show that individually housed mice exhibited more anxiety-related behaviors over a 5 min testing period than the other experimental groups. Use of the handling procedure was associated with a statistically significant reduction in anxiety-related behaviors among individually housed mice. No effects on anxiety-related behavior levels were observed when group housed animals were handled. When activity levels were significantly increased, a new parameter, "Time by Entries", helped to prevent activity from influencing anxiety parameters such as time in the open section of the zero maze test. This knowledge can help to design more efficient experiments without bias from data obtained by means of unconditioned tests.

  18. Acute effects of ketamine in the holeboard, the elevated-plus maze, and the social interaction test in Wistar rats.

    Science.gov (United States)

    Silvestre, J S; Nadal, R; Pallarés, M; Ferré, N

    1997-01-01

    Although noncompetitive NMDA receptor antagonists have shown an anxiolyticlike profile in several studies, such effects have not been observed consistently. Previous studies with ketamine, a noncompetitive NMDA antagonist, have employed only shock tests of anxiety based on conflict procedures. In the present experiment, the effect of an acute low dose of ketamine (7 mg/kg) was examined in adult male Wistar rats tested in three nonconflict tests: holeboard, social interaction, and elevated plus-maze paradigms. The results showed that ketamine decreased time spent in active social interaction and the number of rearings and central activity in the social interaction test. It also decreased the number of entries into the percentage of time spent in open arms and the total number of entries in the elevated plus-maze. No significant effect was observed in head dipping in the holeboard test, although the number of crossings did increase. These results suggest an anxiogeniclike effect of ketamine in contrast with results previously described for noncompetitive NMDA receptor antagonists. These effects of ketamine are more similar to those described for stimulant drugs such as caffeine, cocaine, or amphetamine in anxiety tests.

  19. AKTIVITAS EKSTRAK RIMPANG TEMULAWAK (Curcuma xanthorrhiza Roxb. PADA RADIAL ARM MAZE DAN PASIVE AVOIDANCE TEST TIKUS MODEL DEMENSIA

    Directory of Open Access Journals (Sweden)

    Didik Yuni Prasetya

    2014-11-01

    Full Text Available Curcuma xanthorrhiza Roxb. is a plant containing curcumin. Curcumin has been shown to reduce oxidative damage and memory deficits associated with aging. The aim of the research was to know the effect of Curcuma xanthorrhiza Roxb. rhizome ethanol extract to memory function on Wistar rats induced by trimethyltin. The research design was post test only controlled group with 42 rats divided into 6 groups, Each group consist of 7 rats. Group I (healthy controls were given a solution of 0.5% CMC-Na orally. Group II (negative control were given a solution of 0.5% CMC-Na orally. Group III, IV, and V were given Curcuma xanthorrhiza Roxb. extract each 120 mg/kgBW, 240 mg/kgBW, and 480 mg/kgBW orally. Group VI (positive control were given piracetam 500 mg/kgBW intraperitoneally. All groups were given trimethyltin intraperitoneally except group I. Data indicating memory function were obtained from radial maze test and passive avoidance test. Radial maze test data were analyzed by ANOVA followed by LSD test, while the passive avoidance test data were analyzed with the Kruskal Wallis test followed by Mann-Whitney test. In conclusion, ethanol extract of temulawak rhizome (Curcuma xanthorrhiza Roxb. at doses of 120 mg/kgBW, 240 mg/kgBW and 480 mg/kgBW can prevent memory function decline on Wistar rats induced by trimethyltin.

  20. 三十日龄Fmr1基因敲除小鼠的水迷宫实验观察%Behavioural comparision on Fmr1 knockout mice at 30 days age in Morris water maze experiment

    Institute of Scientific and Technical Information of China (English)

    孙卫文; 黄越玲; 张维雯; 刘国彬; 沈岩松; 李敏雄; 戴丽军; 陈盛强

    2011-01-01

    目的 实验对30日龄的Fmr1基因敲除(KO)小鼠的经典Morris水迷宫实验进行观察.方法 采用Morris水迷宫实验,测试1月龄KO小鼠与WT小鼠的学习记忆功能.水迷宫实验共训练4 d,记录每天的潜伏期与游泳轨迹,第5天去除平台,记录小鼠停留各象限的时间百分比.根据所获得的数据进行多因素方差分析处理.结果 ①空间航行实验第1天至第3天实验中KO鼠与WT鼠的潜伏期和穿越平台次数差异无统计学意义(P>0.05);在第4天实验中KO鼠的潜伏期和穿越平台次数比WT鼠差异有统计学意义(JP<0.05).②空间搜索实验4周龄WT鼠在目标象限停留时间比其它象限停留时间长;4周龄KO鼠在第二象限停留时间长.结论 30日龄KO小鼠存在认知功能障碍.%Objective To compare the behaviour defferences at 30 days age in Morris water maze experiment.Methods Fmr1 knockout mice were identified using the PCR technique , and Morris water maze experiment were used in the study.The data was analyzed with Multifactor Variance Analysis.Results ①space navigation experiment from the first day to the third day, KO mice have no obviously difference with the WT mice in the Latency and number of crossing platform (P> 0.05) , but on the fourth day , there was a statistical significance (P< 0.05) ; ②Space search experiment.The four-week WT mice will stay longer than the other mice at the target quadrants; the four-week KO mice stay at the second quadrant longer.Conclusion Fmr1 knockout animals exhihited low ability of learning and memorizing in the Morris water maze task at 30 days Age.

  1. Anxiolytic-like effect of the selective neuropeptide Y Y2 receptor antagonist BIIE0246 in the elevated plus-maze.

    Science.gov (United States)

    Bacchi, Fabrizio; Mathé, Aleksander A; Jiménez, Patricia; Stasi, Luigi; Arban, Roberto; Gerrard, Philip; Caberlotto, Laura

    2006-12-01

    The involvement of Neuropeptide Y (NPY) in the pathophysiology of mood disorders has been suggested by clinical and preclinical evidence. NPY Y1 and Y2 receptors have been proposed to mediate the NPY modulation of stress responses and anxiety related behaviors. To further investigate the role of Y2 receptors in anxiety we studied the effect of BIIE0246, a selective Y2 receptor antagonist, in the elevated plus-maze test. Rats treated with 1.0 nmol BIIE0246 showed an increase in the time spent on the open arm of the maze. In addition, to study the effects of the Y2 antagonism on NPY protein level, NPY-like immunoreactivity was measured in different brain regions following treatment with BIIE0246, but no statistically significant effects were observed. These results suggest that BIIE0246 has an anxiolytic-like profile in the elevated plus-maze.

  2. The inactivation of the basolateral nucleus of the rat amygdala has an anxiolytic effect in the elevated T-maze and light/dark transition tests

    Directory of Open Access Journals (Sweden)

    Bueno C.H.

    2005-01-01

    Full Text Available Pharmacological evidence indicates that the basolateral nucleus of the amygdala (BLA is involved in the mediation of inhibitory avoidance but not of escape behavior in the elevated T-maze test. These defensive responses have been associated with generalized anxiety disorder (GAD and panic disorder, respectively. In the present study, we determined whether the BLA plays a differential role in the control of inhibitory avoidance and escape responses in the elevated T-maze. Male Wistar rats (250-280 g, N = 9-10 in each treatment group were pre-exposed to one of the open arms of the maze for 30 min and 24 h later tested in the model after inactivation of the BLA by a local injection of the GABA A receptor agonist muscimol (8 nmol in 0.2 µL. It has been shown that a prior forced exposure to one of the open arms of the maze, by shortening latencies to withdrawal from the open arm during the test, improves the escape task as a behavioral index of panic. The effects of muscimol in the elevated T-maze were compared to those caused by this GABA agonist in the avoidance reaction generated in the light/dark transition test. This defensive behavior has also been associated with GAD. In the elevated T-maze, intra-BLA injection of muscimol impaired inhibitory avoidance (control: 187.70 ± 14.90 s, muscimol: 37.10 ± 2.63 s, indicating an anxiolytic effect, without interfering with escape performance. The drug also showed an anxiolytic effect in the light/dark transition test as indicated by the increase in the time spent in the lighted compartment (control: 23.50 ± 2.45 s, muscimol: 47.30 ± 4.48 s. The present findings point to involvement of the BLA in the modulation of defensive responses that have been associated with GAD.

  3. mGluR3 knockout mice show a working memory defect and an enhanced response to MK-801 in the T- and Y-maze cognitive tests.

    Science.gov (United States)

    Lainiola, Mira; Procaccini, Chiara; Linden, Anni-Maija

    2014-06-01

    Polymorphisms in the metabotropic glutamate receptor 3 (mGluR3) encoding gene GRM3 have been linked to schizophrenia and cognitive performance in humans. Our aim was to analyze the role of mGluR3 in basal working memory and attentional processes, and also when these functions were distracted by the psychotomimetic N-methyl-d-aspartate (NMDA) receptor antagonist dizocilpine (MK-801). mGluR3 knockout (KO) mice were used. Spontaneous alternation in a T-maze test was significantly reduced in mGluR3-KO mice compared to wildtype (WT) mice, particularly after a low dose of MK-801 (0.03 mg/kg, i.p., 30 min). In a Y-maze novelty discrimination test, the locomotor stimulatory effect of MK-801 (0.1mg/kg) was enhanced in mGluR3-KO mice. Interestingly, mGluR3-KO mice showed the significantly reduced alternation in the spontaneous alternation T-maze test and the significantly enhanced sensitivity to MK-801 in the Y-maze test only when forced to enter the right arm first, not when the forced arm was on the left. A side-biased response was also found in a rewarded alternation T-maze test, where mGluR3-KO mice made significantly more incorrect visits to the left arm than the right arm after a 25-s delay. No genotype difference was found in the novelty discrimination in the Y-maze test, rewarded alternation with a 5-s delay, preference for left or right when free to enter either arm or in MK-801-induced circling. Our findings indicate cognitive disturbance and left-right asymmetry in certain behavioral responses of mGluR3-KO mice. This novel observation warrants further elucidation, and should also be considered in other studies of mGluR3 in brain functions.

  4. Proofs of the Technical Results Justifying a Biologically Inspired Algorithm for Reactive Navigation of Nonholonomic Robots in Maze-Like Environments

    CERN Document Server

    Matveev, Alexey S; Savkin, Andrey V

    2011-01-01

    We present technical results justifying a method for guidance of a Dubins-like vehicle with saturated control towards a target in a steady simply connected maze-like environment. The vehicle always has access to to the target relative bearing angle and the distance to the nearest point of the maze if it is within the given sensor range. The proposed control law is composed by biologically inspired reflex-level rules. Mathematically rigorous analysis of this law is provided; its convergence and performance are confirmed by computer simulations and experiments with real robots.

  5. Effects of mescaline and its derivative N-[3,4,5-trimethoxyphenylethyl]-aziridine on the spatial orientation of rats in a T-maze.

    Science.gov (United States)

    Koupilová, M; Herink, J

    1989-01-01

    The central effect of mescaline and of its derivative N-[3,4,5- trimethoxyphenylethyl]-aziridine (FAZ) after their stereotaxic administration into the lateral ventricle of the brain was studied in behavioural experiments on rats. The effect of the two substances was tested by a method studying memory elicitation in response to appetitive motivation in a multiple T-maze. The results show that both substances worsened the behaviour in question. The negative effect of mescaline (lengthening of the time of passage through the maze) was manifested both immediately and several weeks after a single dose. FAZ likewise worsened the test reaction, but its effect was less pronounced than that of mescaline.

  6. The Role of Metabotropic Glutamate Receptor 5 in Learning and Memory Processes

    DEFF Research Database (Denmark)

    Simonyi, Agnes; Schachtman, Todd; Christoffersen, Gert Rene Juul

    2005-01-01

    signaling mechanisms have also been revealed. MGluR5s are mainly localized postsynaptically on the periphery of synap-ses. MGluR5s have been implicated in synaptic plasticity and learning and memory. The development of the highly potent and selective mGluR5 antagonist 2-methyl-6-(phenylethynyl...... of the effects of MPEP in various behavioral paradigms have concluded that mGluR5s play a critical role in aversive learning tasks and in hippocampal-dependent spatial learning. However, MPEP has proved ineffective in certain other learning tasks. MGluR5 knockout mice have shown impairments in water maze...... and radial arm maze performance as well as in contextual fear conditioning, but not in cue conditioning. This review summarizes recent advances reported on mGluR5 function in synaptic plasticity, learning and memory. The current development of positive and negative allosteric modulators of mGluR5...

  7. Monte Carlo simulations for the design of the treatment rooms and synchrotron access mazes in the CNAO Hadrontherapy facility.

    Science.gov (United States)

    Porta, Alessandro; Agosteo, Stefano; Campi, Fabrizio

    2005-01-01

    The Italian National Centre for Hadrontherapy is based on a synchrotron capable of accelerating protons and carbon ions up to 250 MeV and 400 MeV u(-1), respectively. The present work describes some Monte Carlo simulations performed to verify the design of the treatment rooms and synchrotron access mazes. The different shielding efficiency and induced activations of the common concrete and the baryte concrete were analysed. In such a radiation field, i.e. with high-energy neutrons, the baryte concrete gains twice the activation than the common concrete without any relevant dose reduction. Moreover, the simulations have stressed, again, the discrepancies between H*(10) and E in such cases where the neutron radiation field is the dominant component and, particularly, in the medium-high energy range.

  8. [Maze procedure in a case of dextrocardia with atrial septal defect and persistent left superior vena cava].

    Science.gov (United States)

    Muraoka, Arata; Kawada, Masaaki; Misawa, Yoshio

    2014-08-01

    A 52-year-old man was diagnosed with dextrocardia at the age of 1 year and was asymptomatic until 1 year before admission. He was transferred to our hospital for management of atrial fibrillation. A transthoracic echocardiogram showed dextrocardia with atrial septal defect;moderate tricuspid valve regurgitation; and a large, persistent left superior vena cava. A cardiac catheterization study revealed that pulmonary flow/systemic flow (Qp/Qs) was 3.6 and that pulmonary vascular resistance was 2.5 Wood U·m². Intracardiac repair with tricuspid annuloplasty and a maze procedure was scheduled. When establishing cardiopulmonary bypass, venous drainage was initially obtained from the inferior vena cava and the left superior vena cava, and the small superior vena cava was then directly cannulated after opening the right atrium. The patient's postoperative course was uneventful, and serial electrocardiograms have demonstrated maintenance of normal sinus rhythm for 3.5 years after the operation.

  9. Anxiolytic-like effects of rose oil inhalation on the elevated plus-maze test in rats.

    Science.gov (United States)

    de Almeida, Reinaldo Nóbrega; Motta, Simone Cristina; de Brito Faturi, Claudia; Catallani, Bruna; Leite, José Roberto

    2004-02-01

    The effect of rose oil inhalation (1.0%, 2.5%, and 5.0% w/w) on the elevated plus-maze (EPM) test was investigated in adult male rats and compared with the effect of diazepam (DZP) (1.0 and 2.0 mg/kg) administered intraperitoneally 30 min before testing. Exposure to rose oil produced an anxiolytic-like effect similar to DZP (anxiolytic reference drug). Thus, at some concentrations, rose oil significantly increased the number of visits to and time spent in the open arms of the EPM. Anxiolytic-like properties of rose oil were observed using the EPM, being consistent with other behavioral and clinical studies.

  10. Intracerebroventricular effects of histaminergic agents on morphine-induced anxiolysis in the elevated plus-maze in rats.

    Science.gov (United States)

    Zarrindast, Mohammad-Reza; Rostami, Parvin; Zarei, Morteza; Roohbakhsh, Ali

    2005-11-01

    Some reports indicate that morphine can induce anxiolytic effects both in animal and in man. It has also been reported that histaminergic system can interfere with some pharmacological effects of morphine. The effects of histaminergic agents on morphine-induced anxiolysis in rats, using elevated plus-maze were investigated in the present study. Intraperitoneal injection of morphine (3, 6 and 9 mg/kg) induced antianxiety effects. Intracerebroventricular administration of histamine at the doses of (5, 10 and 20 microg/rat) also increased anxiety-related behaviours. Intracerebroventricular injection of pyrilamine, a H1 receptor antagonist (25, 50 and 100 microg/rat), increased anxiety whereas injection of ranitidine, a H2 receptor antagonist (5, 10 and 20 microg/rat) at the same site, decreased anxiety. Therefore, it seems that histamine induces anxiogenic response through activation of H2 receptors, while the response of H1 blocker may be due to release of histamine. We also evaluated the interactions between morphine and histaminergic agents. Our data show that histamine (10 microg/rat), pyrilamine (50 microg/rat) and ranitidine (5 microg/rat) did not alter the response induced by different doses of morphine (3, 6 and 9 mg/kg). Similarly, a single dose of morphine did not alter the response induced by different doses of histamine (5, 10 and 20 microg/rat), pyrilamine (25, 50 and 100 microg/rat) or ranitidine (5, 10 and 20 microg/rat). In conclusion, the histaminergic system plays an important role in the modulation of anxiety, although in our experiments, no interaction was found between the effects of histaminergic agents and morphine on anxiety-related indices in the elevated plus-maze. This may imply that morphine-induced anxiolysis probably is independent of the histaminergic system.

  11. Behavioral and pharmacological investigation of anxiety and maternal responsiveness of postpartum female rats in a pup elevated plus maze.

    Science.gov (United States)

    Yang, Yu; Qin, Jingxue; Chen, Weihai; Sui, Nan; Chen, Hong; Li, Ming

    2015-10-01

    The present study investigated the validity of a novel pup-based repeated elevated plus maze task to detect reduced anxiety and increased maternal responsiveness in postpartum female rats and explored the roles of dopamine D2, serotonin transporter and GABA/benzodiazepine receptors in the mediation of these processes. Sprague-Dawley postpartum or nulliparous female rats were tested 4 times every other day on postpartum days 4, 6 and 8 in an elevated plus maze with 4 pups or 4 pup-size erasers placed on each end of the two open arms. When tested with erasers, untreated postpartum mother rats entered the open arms proportionally more than nulliparous rats. They also tended to spend more time in the open arms, indicating reduced anxiety. When tested with pups, postpartum rats retrieved pups into the closed arms, entered the open arms and closed arms more and had a higher moving speed than nulliparous rats, indicating increased maternal responsiveness. Both haloperidol (0.1 or 0.2 mg/kg, sc) and fluoxetine (5 or 10 mg/kg, ip) dose- and time-dependently decreased the percentage of time spent in the open arms and speed, but did not affect the percentage of open arm entries. Diazepam (1.0 or 2.0 mg/kg, ip) did not affect pup retrieval, open arm time/entry in lactating rats. Thus, the percentage of open arm entries appears to be the most sensitive measure of anxiety in postpartum female rats, while speed could be used to index maternal responsiveness to pups, which are likely mediated by the dopamine D2 and serotonin transporter systems.

  12. Cyamemazine as an anxiolytic drug on the elevated plus maze and light/dark paradigm in mice.

    Science.gov (United States)

    Bourin, M; Nic Dhonnchadha BA; Claude Colombel, M; Dib, M; Hascoët, M

    2001-09-28

    Several studies have demonstrated that cyamemazine, a classic antipsychotic compound, possesses anxiolytic properties in humans as well as a potent antagonistic effect on 5-HT(2C) and 5-HT(3) receptors. In this study the level of anxiety of mice was assessed in the light/dark exploration test and the elevated plus maze (EPM) following both acute and chronic administration. Spontaneous locomotor activity was measured using a photoelectric actimeter. Acute or chronic administration of cyamemazine dramatically decreases the spontaneous locomotor activity of mice at the dose of 1 mg/kg in comparison with the control group. In the light/dark exploration test, cyamemazine (0.375 mg/kg) only demonstrated anxiolytic-like activity following acute administration. In the elevated plus maze (EPM), cyamemazine did not induce any anxiolytic like effects after acute administration. However, after chronic administration, cyamemazine at doses of 0.25, 0.375, 0.5 and 1 mg/kg significantly increased the time spent in the open arms. The number of open arm entries was also increased at 0.25 and 0.5 mg/kg. Various serotonergic ligands were then used to examine the role of the various receptors in mediating the effects of cyamemazine in the EPM. Concerning the 5-HT(2) ligands DOI and mCPP antagonised the effects of cyamemazine and N-desmethyl clozapine potentiated the effects. For 2-methyl-5-HT and ondansetron, the 5-HT(3) receptor ligands did not seem to have any effect. It appears that the 5-HT(2C) receptors are more implicated in the function of mediating the anxiolytic effect of cyamemazine in the EPM. The discrepancy of results obtained in the tests, following acute or chronic administration could be the result of the combined activity of dopamine D(2) receptor antagonism with antagonism of 5-HT(2C) and 5-HT(3) receptors.

  13. Effects of Boswellia Papyrifera Gum Extract on Learning and Memory in

    Directory of Open Access Journals (Sweden)

    Amir Farshchi

    2010-04-01

    Full Text Available Objective(sLearning is defined as the acquisition of information and skills, while subsequent retention of that information is called memory. The objective of the present study was to investigate the effect of aqueous extract of Boswellia papyrifera on learning and memory paradigms in mice and rats.Materials and MethodsThis study was held at the Department of Pharmacology, Faculty of Pharmacy, Kermanshah University of Medical Science, Kermanshah, Iran from September 2006 to March 2008. Male Wistar rats and male NMRI mice were randomly divided into control, B. papyrifera treated (50, 100, 150 mg/kg, p.o., and piracetam (150 mg/kg groups. Radial arm maze (RAM and Morris water maze (MWM were the screening tests used to assess the activity of B. papyrifera extract.ResultsThe mice treated with B. papyrifera (50, 100 and 150 mg/kg or piracetam (150 mg/kg showed a decrease in number of days required to learned (P< 0.05 and time taken to find food by the learned mice in radial arm maze (P< 0.01. In Morris water maze, rats treated with the above mentioned doses showed dose dependent improvement in spatial learning. Escape latency during swimming in water maze in piracetam and B. papyrifera treated animals was significantly lower (P< 0.01 than control. Swimming distance was also significantly lower (P< 0.05 in the treated groups.Conclusion The results show facilitation of spatial learning and memory processes and thereby validate B. papyrifera traditional use of intelligence improving. The presence of alkaloids, flavonoids and saponins might be responsible for this activity of B. papyrifera.

  14. Effects of Ethanol-Gasoline Blended Fuels on Learning and Memory

    Science.gov (United States)

    The potential toxicity of ethanol-gasoline blended fuels to the developing nervous system is of concern. We previously reported an absence of effect on learning and memory as seen in a trace fear conditioning task and water maze task in offspring of dams exposed prenatally to the...

  15. Pre-Exposure to Context Affects Learning Strategy Selection in Mice

    Science.gov (United States)

    Tunur, Tumay; Dohanich, Gary P.; Schrader, Laura A.

    2010-01-01

    The multiple memory systems hypothesis proposes that different types of learning strategies are mediated by distinct neural systems in the brain. Male and female mice were tested on a water plus-maze task that could be solved by either a place or response strategy. One group of mice was pre-exposed to the same context as training and testing (PTC)…

  16. Research and Optimization of Micro-mouse Thronging the Maze Algorithm%电脑鼠走迷宫算法的研究与优化

    Institute of Scientific and Technical Information of China (English)

    高鹏; 秦文华; 马超; 李梦

    2013-01-01

    电脑鼠是一个集自主迷宫搜索、搜索完成之后进行最短路径冲刺、传感与控制于一体的自主移动机器人系统。针对IEEE标准电脑鼠走迷宫竞赛的要求,介绍了一种基于ARM芯片LM3S615控制的嵌入式电脑鼠走迷宫算法的改进与优化,并对电脑鼠转弯算法进行了深入探讨。实验结果显示,优化后的算法很好地实现了在IEEE标准迷宫中快速搜索最佳路径。%Micro-mouse is an autonomous mobile robot integrating self-maze search, the shortest path sprint after the search, and sensing and control. In this paper, aiming at the requirements of IEEE standard for Micro-mouse thronging maze competition, the improvement and optimization of an embedded Micro-mouse thronging maze algorithm based on ARM chip LM3S615 control is introduced. and the algorithm for Micro-mouse turning is discussed deeply. Finally, the experiment result shows that the algorithm after optimization can let Micro-mouse search a optimal path quickly and accurately in a maze specified by IEEE standard.

  17. Tests of the Aversive Summation Hypothesis in Rats: Effects of Restraint Stress on Consummatory Successive Negative Contrast and Extinction in the Barnes Maze

    Science.gov (United States)

    Ortega, Leonardo A.; Prado-Rivera, Mayerli A.; Cardenas-Poveda, D. Carolina; McLinden, Kristina A.; Glueck, Amanda C.; Gutierrez, German; Lamprea, Marisol R.; Papini, Mauricio R.

    2013-01-01

    The present research explored the effects of restraint stress on two situations involving incentive downshift: consummatory successive negative contrast (cSNC) and extinction of escape behavior in the Barnes maze. First, Experiment 1 confirmed that the restraint stress procedure used in these experiments increased levels of circulating…

  18. Effects of Stress, Corticosterone, and Epinephrine Administration on Learning in Place and Response Tasks

    OpenAIRE

    Sadowski, Renee N.; Jackson, Gloria R.; Wieczorek, Lindsay A.; Gold, Paul E.

    2009-01-01

    These experiments examined the effects of prior stress, corticosterone, or epinephrine on learning in mazes that can be solved efficiently using either place or response strategies. In a repeated stress condition, rats received restraint stress for 6 h/day for 21 days, ending 24 h before food-motivated maze training. In two single-stress conditions, rats received a 1-h episode of restraint stress ending 30 min or 24 h prior to training. Single stress ending 30 min prior to training resulted i...

  19. Colour as an environmental cue when learning a route in a virtual environment: typical and atypical development.

    Science.gov (United States)

    Farran, Emily K; Courbois, Yannick; Van Herwegen, Jo; Cruickshank, Alice G; Blades, Mark

    2012-01-01

    Typically developing (TD) 6-year-olds and 9-year-olds, and older children and adults with Williams syndrome (WS) navigated through brick-wall mazes in a virtual environment. Participants were shown a route through three mazes, each with 6 turns. In each maze the floor of each path section was a different colour such that colour acted as an environmental cue. The colours employed were either easy to verbalise (focal colours) or difficult to verbalise (non-focal colours). We investigated whether participants would verbally code the colour information in the focal colour condition only, and whether this facilitated route-learning. All groups could learn the routes; the WS group required more learning trials to learn the route and achieved lower memory scores than both of the TD groups. Despite this, all groups showed the same pattern of results. There was no effect of condition on the ability to learn the maze. However, when asked which colours featured in each route, higher memory scores were achieved for the focal colour (verbalisable) than the non-focal colour (non-verbalisable) condition. This suggests that, in both young children and individuals with WS, once a route has been learnt, the nature of the environmental cues within it can impact an individual's representation of that route.

  20. Hippocampal-dependent memory in the plus-maze discriminative avoidance task: The role of spatial cues and CA1 activity.

    Science.gov (United States)

    Leão, Anderson H F F; Medeiros, André M; Apolinário, Gênedy K S; Cabral, Alícia; Ribeiro, Alessandra M; Barbosa, Flávio F; Silva, Regina H

    2016-05-01

    The plus-maze discriminative avoidance task (PMDAT) has been used to investigate interactions between aversive memory and an anxiety-like response in rodents. Suitable performance in this task depends on the activity of the basolateral amygdala, similar to other aversive-based memory tasks. However, the role of spatial cues and hippocampal-dependent learning in the performance of PMDAT remains unknown. Here, we investigated the role of proximal and distal cues in the retrieval of this task. Animals tested under misplaced proximal cues had diminished performance, and animals tested under both misplaced proximal cues and absent distal cues could not discriminate the aversive arm. We also assessed the role of the dorsal hippocampus (CA1) in this aversive memory task. Temporary bilateral inactivation of dorsal CA1 was conducted with muscimol (0.05 μg, 0.1 μg, and 0.2 μg) prior to the training session. While the acquisition of the task was not altered, muscimol impaired the performance in the test session and reduced the anxiety-like response in the training session. We also performed a spreading analysis of a fluorophore-conjugated muscimol to confirm selective inhibition of CA1. In conclusion, both distal and proximal cues are required to retrieve the task, with the latter being more relevant to spatial orientation. Dorsal CA1 activity is also required for aversive memory formation in this task, and interfered with the anxiety-like response as well. Importantly, both effects were detected by different parameters in the same paradigm, endorsing the previous findings of independent assessment of aversive memory and anxiety-like behavior in the PMDAT. Taken together, these findings suggest that the PMDAT probably requires an integration of multiple systems for memory formation, resembling an episodic-like memory rather than a pure conditioning behavior. Furthermore, the concomitant and independent assessment of emotionality and memory in rodents is relevant to

  1. Effects of ziprasidone, SCH23390 and SB277011 on spatial memory in the Morris water maze test in naive and MK-801 treated mice.

    Science.gov (United States)

    Tanyeri, Pelin; Buyukokuroglu, Mehmet Emin; Mutlu, Oguz; Ulak, Güner; Akar, Füruzan Yildiz; Celikyurt, Ipek Komsuoglu; Erden, Bekir Faruk

    2015-11-01

    Introduction: Patients with schizophrenia have cognitive dysfunctions; positive psychotic symptoms are the primary purposes for schizophrenia treatment. Improvements in cognitive function should be a characteristic of all newly developed drugs for the treatment of schizophreniawith dementia. Thus,we investigated the effects of the second-generation antipsychotic ziprasidone, dopamine D1 antagonist SCH-23390 and dopamine D3 antagonist SB-277011 on spatial learning and memory. Materials and methods: Male inbred mice were used. The effects of ziprasidone, SCH-23390 and SB-277011 were investigated using the Morris water maze test. Results: Ziprasidone (0.5 and 1mg/kg), SCH-23390 (0.05 and 0.1 mg/kg) and SB-277011 (10 and 20 mg/kg) had no effect on the time spent in the target quadrant in naive mice.MK-801 (0.1mg/kg) significantly decreased the time spent in the target quadrant. The time spent in the target quadrant was significantly prolonged by Ziprasidone (0.5 and 1 mg/kg) and SCH-23390 (0.1 mg/kg), but not with SB-277011 (20 mg/kg) in MK-801-treated mice. Ziprasidone (0.5 and 1mg/kg), SCH-23390 (0.05 and 0.1 mg/kg) and SB-277011 (10 and 20 mg/kg) had no effect on themean distance to the platformin naivemice.MK-801 significantly increased themean distance to the platform. Ziprasidone (1 mg/kg) and SCH-23390 (0.1 mg/kg) significantly decreased the mean distance to the platform in MK-801-treated mice, but SB-277011 (20 mg/kg) didn't. MK-801 significantly increased the total distance moved. Ziprasidone (0.5 and 1 mg/kg), SCH-23390 (0.05 and 0.1 mg/kg) and SB-277011 (10 and 20 mg/kg) had no effect on the total distance moved in naive mice. Ziprasidone (1 mg/kg) and SCH-23390 (0.1 mg/kg) significantly decreased the total distance moved in MK-801-treated mice, but SB-277011 (20 mg/kg) didn't. Conclusions: The second-generation antipsychotic drug ziprasidone and D1 antagonist SCH23390, but not the D3 antagonist SB277011, might be clinically useful for the treatment of

  2. Variations in illumination, closed wall transparency and/or extramaze space influence both baseline anxiety and response to diazepam in the rat elevated plus-maze.

    Science.gov (United States)

    Violle, Nicolas; Balandras, Frédérique; Le Roux, Yves; Desor, Didier; Schroeder, Henri

    2009-10-12

    Numerous methodological-related variables have been demonstrated to influence the baseline anxiety level of rodents exposed to the elevated plus-maze (EPM), raising questions about the sensitivity of this test for the detection of the effects of anxiolytic drugs. Thus, the present study was designed (1) to assess the combined effects of illumination (40-lx red or white light), closed wall type (walls made of translucent or opaque material) and extramaze space size (small or spacious experimental room) on rat behaviour, and (2) to investigate the effects of such parameters on the relevance of the maze for detecting the effects of diazepam orally administrated at the anxiolytic dose of 3 mg/kg. Results indicate that illumination and closed wall type are two main independent parameters that are able to modify the open arm avoidance. Moreover, the closed wall type interacts with the extramaze space size since the reduction of the open arm exploration induced by opaque closed walls is two-fold stronger in the spacious experimental room than in the small one. Finally, the diazepam anxiolytic activity is significantly detected in our laboratory in specific EPM conditions (maze with opaque walls, use of a red light, maze located in a spacious experimental room). In conclusion, the present study demonstrates that an inappropriate baseline anxiety level due to the methodological use of the EPM can dramatically reduce the sensitivity of the maze for the detection of benzodiazepine-related compounds. This study also provides new insights into the perception of the EPM open space in rats.

  3. Effect of the use-dependent, nicotinic receptor antagonist BTMPS in the forced swim test and elevated plus maze after cocaine discontinuation in rats.

    Science.gov (United States)

    Hall, Brandon J; Pearson, Laura S; Buccafusco, Jerry J

    2010-04-26

    Withdrawal from cocaine use often is associated with anxiety and depressive states. In this study the use-dependent, nicotinic acetylcholine receptor antagonist bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (BTMPS) was studied for its ability to reduce these symptoms in two rat models of anxiety and depression. Rats were administered saline vehicle, or two escalating doses of cocaine, for a period of 5 days and they were evaluated during the period after cocaine discontinuation in the elevated plus maze (anxiety) and the forced swim test (affect). BTMPS (0.25, 0.5, or 0.75mg/kg) was co-administered with saline or cocaine in the dependence phase. Withdrawal from cocaine administration alone resulted in reductions in both the time spent in the open arms of the elevated plus maze test, as well as entries into, and out of, the open arms of the maze. Withdrawal from cocaine also resulted in a reduction of escape behaviors, and the time to first immobility, in the forced swim test. Treatment with BTMPS produced a reversal of cocaine-induced anxiety-like behaviors in the elevated plus maze, including an increase (up to 68%) in time spent in the open arms of the maze and an increase in the number of crossings between open and enclosed arms. BTMPS also reduced depressive-like behaviors associated with the forced swim test, including up to a 62% increase in the time to first immobility and a 50% increase in escape behavior. These results provide proof of concept for the development and use of cholinergic compounds in the treatment of substance abuse.

  4. Activation of septal 5-HT1A receptors alters spatial memory encoding, interferes with consolidation, but does not affect retrieval in rats subjected to a water-maze task.

    Science.gov (United States)

    Koenig, Julie; Cosquer, Brigitte; Cassel, Jean-Christophe

    2008-01-01

    Using Long-Evans rats tested in a water maze, this study assessed the role of 5-HT1A/5-HT7 receptors of the medial septum in encoding, consolidation, and retrieval of spatial information. The testing protocol (acquisition: daily four-trial sessions over three consecutive days; retention: probe trial on day 4) was first validated by showing that intraseptal infusions of lidocaine (LIDO; 40 microg/0.5 microL) disrupted acquisition and retrieval of the task. 8-OH-DPAT (4 microg/0.5 microL) infused before each acquisition session prevented learning/retention of the platform location, an effect attenuated by pretreatment with the 5-HT1A receptor antagonist WAY 100635. With the 5-HT7 antagonist SB 269970, the 8-OH-DPAT-induced acquisition deficit seemed attenuated, but there was no subsequent retention. When infused immediately, 1, 4, or 6 h after each acquisition session, 8-OH-DPAT did not hinder consolidation. When the infusions were performed 2 h postacquisition, however, consolidation was disrupted. Finally, when infused before a probe trial after drug-free acquisition, 8-OH-DPAT had no effect, suggesting no interference with retrieval processes. We also established that 8-OH-DPAT had no effects when the platform was visible, and altered neither home-cage activity nor anxiety-related behavior (elevated plus-maze). Altogether, these results show that 5-HT1A receptors in the septal region contribute both to declarative-like information encoding and subsequently, within a given postacquisition time window, to its consolidation. They do not participate in the retrieval of recently learned declarative-like information. These observations suggest that 5-HT1A receptors of the medial septum contribute to a serotonin-mediated mechanism involved in the encoding and consolidation, not the retrieval of spatial hippocampal-dependent knowledge. These results might have some relevance to approaches aimed at modifying serotonergic functions in the brain for the treatment of

  5. Changes in corticostriatal connectivity during reinforcement learning in humans.

    Science.gov (United States)

    Horga, Guillermo; Maia, Tiago V; Marsh, Rachel; Hao, Xuejun; Xu, Dongrong; Duan, Yunsuo; Tau, Gregory Z; Graniello, Barbara; Wang, Zhishun; Kangarlu, Alayar; Martinez, Diana; Packard, Mark G; Peterson, Bradley S

    2015-02-01

    Many computational models assume that reinforcement learning relies on changes in synaptic efficacy between cortical regions representing stimuli and striatal regions involved in response selection, but this assumption has thus far lacked empirical support in humans. We recorded hemodynamic signals with fMRI while participants navigated a virtual maze to find hidden rewards. We fitted a reinforcement-learning algorithm to participants' choice behavior and evaluated the neural activity and the changes in functional connectivity related to trial-by-trial learning variables. Activity in the posterior putamen during choice periods increased progressively during learning. Furthermore, the functional connections between the sensorimotor cortex and the posterior putamen strengthened progressively as participants learned the task. These changes in corticostriatal connectivity differentiated participants who learned the task from those who did not. These findings provide a direct link between changes in corticostriatal connectivity and learning, thereby supporting a central assumption common to several computational models of reinforcement learning.

  6. Loganin improves learning and memory impairments induced by scopolamine in mice.

    Science.gov (United States)

    Kwon, Seung-Hwan; Kim, Hyoung-Chun; Lee, Seok-Yong; Jang, Choon-Gon

    2009-10-01

    Loganin is an iridoid glycoside found in the Flos lonicerae, Fruit cornus, and Strychonos nux vomica. We investigated the effect of loganin on learning and memory impairments induced by scopolamine (0.5mg/kg, i.p.), a muscarinic antagonist, using the Y-maze, passive avoidance, and the Morris water maze tests in mice. In the Y-maze test, loganin (40 mg/kg, p.o.) significantly improved the scopolamine-induced memory impairment. In addition, loganin (20 and 40 mg/kg, p.o.) significantly reversed scopolamine-induced impairments measured by the passive avoidance and the Morris water maze tests. A day after the last trial session of the Morris water maze test (probe trial session), loganin (20 and 40 mg/kg) dose-dependently increased the latency time in the target quadrant. Furthermore, loganin significantly inhibited acetylcholinesterase activity in the hippocampus and frontal cortex. Loganin may have anti-amnesic activity that may hold significant therapeutic value in alleviating certain memory impairments observed in Alzheimer's disease.

  7. Exercise Enhances Learning and Hippocampal Neurogenesis in Aged Mice

    Science.gov (United States)

    Praag, Henriette van; Shubert, Tiffany; Zhao, Chunmei; Gage, Fred H.

    2005-01-01

    Aging causes changes in the hippocampus that may lead to cognitive decline in older adults. In young animals, exercise increases hippocampal neurogenesis and improves learning. We investigated whether voluntary wheel running would benefit mice that were sedentary until 19 months of age. Specifically, young and aged mice were housed with or without a running wheel and injected with bromodeoxyuridine or retrovirus to label newborn cells. After 1 month, learning was tested in the Morris water maze. Aged runners showed faster acquisition and better retention of the maze than age-matched controls. The decline in neurogenesis in aged mice was reversed to 50% of young control levels by running. Moreover, fine morphology of new neurons did not differ between young and aged runners, indicating that the initial maturation of newborn neurons was not affected by aging. Thus, voluntary exercise ameliorates some of the deleterious morphological and behavioral consequences of aging. PMID:16177036

  8. Evolving Neural Turing Machines for Reward-based Learning

    DEFF Research Database (Denmark)

    Jacobsen, Emil Juul; Risi, Sebastian; Greve, Rasmus Boll

    2016-01-01

    and integrating new information without losing previously acquired skills. Here we build on recent work by Graves et al. [5] who extended the capabilities of an ANN by combining it with an external memory bank trained through gradient descent. In this paper, we introduce an evolvable version of their Neural...... Turing Machine (NTM) and show that such an approach greatly simplifies the neural model, generalizes better, and does not require accessing the entire memory content at each time-step. The Evolvable Neural Turing Machine (ENTM) is able to solve a simple copy tasks and for the first time, the continuous...... version of the double T-Maze, a complex reinforcement-like learning problem. In the T-Maze learning task the agent uses the memory bank to display adaptive behavior that normally requires a plastic ANN, thereby suggesting a complementary and effective mechanism for adaptive behavior in NE....

  9. Experimental hypothyroidism delays field excitatory post-synaptic potentials and disrupts hippocampal long-term potentiation in the dentate gyrus of hippocampal formation and Y-maze performance in adult rats.

    Science.gov (United States)

    Artis, A S; Bitiktas, S; Taşkın, E; Dolu, N; Liman, N; Suer, C

    2012-03-01

    Manipulations of thyroid hormones have been shown to influence learning and memory. Although a large body of literature is available on the effect of thyroid hormone deficiency on learning and memory functions during the developmental stage, electrophysiological and behavioural findings, particularly on propylthiouracil administration to adult normothyroid animals, are not satisfactory. The experiments in the present study were carried out on 12 adult male Wistar rats aged 6-7 months. Hypothyroidism was induced by administering 6-n-propyl-2-thiouracil in their drinking water for 21 days at a concentration of 0.05%. The spatial learning performance of hypothyroid and control rats was studied on a Y-maze. The rats were then placed in a stereotaxic frame under urethane anaesthesia. A bipolar tungsten electrode was used to stimulate the medial perforant path. A glass micropipette was inserted into the granule cell layer of the ipsilateral dentate gyrus to record field excitatory post-synaptic potentials. After a 15-min baseline recording of field potentials, long-term potentiation was induced by four sets of tetanic trains. The propylthiouracil-treated rats showed a significantly attenuated input-output (I/O) relationship when population spike (PS) amplitudes and field excitatory post-synaptic potentials (fEPSP) were compared. fEPSP and PS latencies were found to be longer in the hypothyroid group than in the control group. The PS amplitude and fEPSP slope potentiations in the hypothyroid rats were not statistically different from those in the control rats, except for the field EPSP slope measured in the post-tetanic and maintenance phases. The hypothyroid rats also showed lower thyroxine levels and poor performance in the spatial memory task. The present study provides in vivo evidence for the action of propylthiouracil leading to impaired synaptic plasticity, which might explain deficit in spatial memory tasks in adult hypothyroid rats.

  10. Learning, memory and exploratory similarities in genetically identical cloned dogs

    OpenAIRE

    Shin, Chi Won; Kim, Geon A; Park, Won Jun; Park, Kwan Yong; Jeon, Jeong Min; Oh, Hyun Ju; Kim, Min Jung; Lee, Byeong Chun

    2016-01-01

    Somatic cell nuclear transfer allows generation of genetically identical animals using donor cells derived from animals with particular traits. To date, few studies have investigated whether or not these cloned dogs will show identical behavior patterns. To address this question, learning, memory and exploratory patterns were examined using six cloned dogs with identical nuclear genomes. The variance of total incorrect choice number in the Y-maze test among cloned dogs was significantly lower...

  11. CBM Progress Monitoring in Foreign Language Learning for Secondary School Students: Technical Adequacy of Different Measures and Scoring Procedures

    Science.gov (United States)

    Chung, Siuman; Espin, Christine A.

    2013-01-01

    The reliability and validity of three curriculum-based measures as indicators of learning English as a foreign language were examined. Participants were 260 Dutch students in Grades 8 and 9 who were receiving English-language instruction. Predictor measures were maze-selection, Dutch-to-English word translation, and English-to-Dutch word…

  12. Effect of acute pesticide exposure on bee spatial working memory using an analogue of the radial-arm maze

    Science.gov (United States)

    Samuelson, Elizabeth E. W.; Chen-Wishart, Zachary P.; Gill, Richard J.; Leadbeater, Ellouise

    2016-12-01

    Pesticides, including neonicotinoids, typically target pest insects by being neurotoxic. Inadvertent exposure to foraging insect pollinators is usually sub-lethal, but may affect cognition. One cognitive trait, spatial working memory, may be important in avoiding previously-visited flowers and other spatial tasks such as navigation. To test this, we investigated the effect of acute thiamethoxam exposure on spatial working memory in the bumblebee Bombus terrestris, using an adaptation of the radial-arm maze (RAM). We first demonstrated that bumblebees use spatial working memory to solve the RAM by showing that untreated bees performed significantly better than would be expected if choices were random or governed by stereotyped visitation rules. We then exposed bees to either a high sub-lethal positive control thiamethoxam dose (2.5 ng‑1 bee), or one of two low doses (0.377 or 0.091 ng‑1) based on estimated field-realistic exposure. The high dose caused bees to make more and earlier spatial memory errors and take longer to complete the task than unexposed bees. For the low doses, the negative effects were smaller but statistically significant, and dependent on bee size. The spatial working memory impairment shown here has the potential to harm bees exposed to thiamethoxam, through possible impacts on foraging efficiency or homing.

  13. Cannabinoid receptor ligands suppress memory-related effects of nicotine in the elevated plus maze test in mice.

    Science.gov (United States)

    Biala, Grazyna; Kruk, Marta

    2008-10-10

    The purpose of the experiments was to examine the memory-related effects of nicotine using the mouse elevated plus maze. It has been shown that the acute doses of nicotine (0.1 and 0.5 mg/kg) significantly decreased the time of transfer latency (TL2) on the retention trial, indicating that nicotine improved memory processes. Similarly, acute doses of the CB1 cannabinoid receptor antagonist AM 251 (0.5, 1, 1.5 and 3 mg/kg) significantly decreased TL2 values. WIN55,212-2, a non-selective CB cannabinoid receptor agonist, at any dose tested (0.25, 0.5 and 1 mg/kg), did not provoke any effect in this model. Moreover, the acute injection of both WIN55,212-2 (0.25 and 0.5 mg/kg) and AM 251 (0.25 mg/kg), prior to injections of nicotine (0.1 and 0.5 mg/kg), significantly prevented nicotine-induced memory improvement. The results of this study provide clear evidence that the endogenous cannabinoid system participates in the responses induced by nicotine on memory-related behaviour in mice.

  14. The Effects of Histaminergic Agents in the Nucleus Accumbens of Rats in the Elevated Plus-Maze Test of Anxiety

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza Zarrindast

    2010-11-01

    Full Text Available ABSTRACTIntroduction/Aims: The nucleus accumbens (NAc receives histaminergic neurons from tuberomammillary nuclei. There are also reports indicating that central histamine systems are involved in many physiological behavioral processes, including anxiety. The aim of the present study was to assess whether the histaminergic system of the NAc is involved in the anxiety-related behaviors. Methods: As a model of anxiety the elevated plus maze which is a useful test to investigate the effects of anxiogenic or anxiolytic drugs in rodents was used in male Wistar rats. Results:Intra-NAc administration of histamine (0.01, 0.1 and 1 μg/rat increased the percentage of open arm time (%OAT and open arm entries (%OAE but not locomotor activity, indicating an anxiolytic response. Furthermore, bilateral microinjections of different doses of the H1 receptor antagonist pyrilamine (0.001, 0.01, 0.1 and 1 μg/rat or the H2 receptor antagonist ranitidine (0.001, 0.01, 0.1 and 1 μg/rat into the NAc increased %OAT and %OAE but not locomotor activity. However, both histamine and histamine receptor antagonists showed an anxiolytic-like effect, the antagonists (1 μg/rat also decreased the histamine response. Discussion: The results may indicate a modulatory effect for the H1 and H2 histamine receptors of nucleus accumbens in the anxiety behavior of rats.

  15. [Air kerma transmission factors of Scattered X-rays in the maze of a Linac room for lead shield].

    Science.gov (United States)

    Kato, Hideki

    2005-01-20

    Spectra of scattered X-rays in the maze of a Linac (X-ray energies of 4, 6, and 10 MV) room were estimated by means of the Monte Carlo simulation, and air kerma transmission factors of the X-rays scattered through a lead shield were evaluated based on those spectra. Spectra of scattered X-rays showed a maximum in the energy area below 200 keV. The higher the accelerated electron energy, also, the smaller the scattering angle that tended to spread to the higher energy area of the distribution of spectra. The air kerma transmission factor of 120 degrees scattered X-rays of 4 MV X-rays obtained in this study was larger than the transmission factors of 124 degrees scattered photons of (60)Co gamma rays through a lead shield given in ICRP. The air kerma transmission factors of 120 degrees scattered X-rays of 6 MV X-rays were smaller than the transmission factors of 90 degrees scattered photons of (60)Co gamma rays. The air kerma transmission factors of 120 degrees scattered X-rays of 10 MV X-rays was slightly larger than transmission factors of 90 degrees scattered photons of (60)Co gamma rays. Therefore, in the case of a 4 MV X-ray Linac room, the calculation method given in the "Manual of Practical Shield Calculation of Radiation Facilities (2000)" causes underestimation of leakage doses.

  16. Vacuum Die Casting Process and Simulation for Manufacturing 0.8 mm-Thick Aluminum Plate with Four Maze Shapes

    Directory of Open Access Journals (Sweden)

    Chul Kyu Jin

    2015-02-01

    Full Text Available Using vacuum die casting, 0.8 mm-thick plates in complicated shapes are manufactured with the highly castable aluminum alloy Silafont-36 (AlSi9MgMn. The sizes and shapes of the cavities, made of thin plates, feature four different mazes. To investigate formability and mechanical properties by shot condition, a total of six parameters (melt temperatures of 730 °C and 710 °C; plunger speeds of 3.0 m/s and 2.5 m/s; vacuum pressure of 250 mbar and no vacuum are varied in experiments, and corresponding simulations are performed. Simulation results obtained through MAGMA software show similar tendencies to those of the experiments. When the melt pouring temperature is set to 730 °C rather than 710 °C, formability and mechanical properties are superior, and when the plunger speed is set to 3.0 m/s rather than to 2.5 m/s, a fine, even structure is obtained with better mechanical properties. The non-vacuumed sample is half unfilled. The tensile strength and elongation of the sample fabricated under a melt temperature of 730 °C, plunger speed of 3.0 m/s, and vacuum pressure of 250 mbar are 265 MPa and 8.5%, respectively.

  17. Nociceptin/orphanin FQ induces simultaneously anxiolytic and amnesic effects in the mouse elevated T-maze task.

    Science.gov (United States)

    Asth, Laila; Correia, Nataly; Lobão-Soares, Bruno; De Lima, Thereza C Monteiro; Guerrini, Remo; Calo', Girolamo; Soares-Rachetti, Vanessa P; Gavioli, Elaine C

    2015-01-01

    Studies have shown a close relationship between anxiety and aversive memory processing, but few animal models are suitable for investigating the effects of a given compound on anxiety and memory simultaneously. A growing body of evidence suggests anxiolytic and amnesic effects of nociceptin/orphanin FQ (N/OFQ). The mouse elevated T-maze (ETM) has been shown to detect the effects of drugs on anxiety and memory at the same time. In this study, the effects of intracerebroventricular N/OFQ injected before or immediately after training session were assessed in the ETM task. When pretraining injected, N/OFQ 0.1 nmol significantly decreased the latency to enter an open arm in the training session compared to control, which is suggestive of anxiolysis. In addition, N/OFQ (0.1 and 1 nmol) significantly reduced the latency to enter an open arm during the test session compared to control, thus suggesting memory impairments. However, when N/OFQ was administered posttraining, it did not affect memory retrieval. No alterations in locomotion were detected in N/OFQ-treated mice in the open field test. In conclusion, these findings are discussed considering the simultaneous anxiolytic and amnesic effects of N/OFQ.

  18. Be aware of neutrons outside short mazes from 10-MV linear accelerators X-rays in radiotherapy facilities.

    Science.gov (United States)

    Brockstedt, S; Holstein, H; Jakobsson, L; Tomaszewicz, A; Knöös, T

    2015-07-01

    During the radiation survey of a reinstalled 10-MV linear accelerator in an old radiation treatment facility, high dose rates of neutrons were observed. The area outside the maze entrance is used as a waiting room where patients, their relatives and staff other than those involved in the actual treatment can freely pass. High fluence rates of neutrons would cause an unnecessary high effective dose to the staff working in the vicinity of such a system, and it can be several orders higher than the doses received due to X-rays at the same location. However, the common knowledge appears to have been that the effect of neutrons at 10-MV X-ray linear accelerator facilities is negligible and shielding calculations models seldom mention neutrons for this operating energy level. Although data are scarce, reports regarding this phenomenon are now emerging. For the future, it is advocated that contributions from neutrons are considered already during the planning stage of new or modified facilities aimed for 10 MV and that estimated dose levels are verified.

  19. Effect of acute pesticide exposure on bee spatial working memory using an analogue of the radial-arm maze.

    Science.gov (United States)

    Samuelson, Elizabeth E W; Chen-Wishart, Zachary P; Gill, Richard J; Leadbeater, Ellouise

    2016-12-13

    Pesticides, including neonicotinoids, typically target pest insects by being neurotoxic. Inadvertent exposure to foraging insect pollinators is usually sub-lethal, but may affect cognition. One cognitive trait, spatial working memory, may be important in avoiding previously-visited flowers and other spatial tasks such as navigation. To test this, we investigated the effect of acute thiamethoxam exposure on spatial working memory in the bumblebee Bombus terrestris, using an adaptation of the radial-arm maze (RAM). We first demonstrated that bumblebees use spatial working memory to solve the RAM by showing that untreated bees performed significantly better than would be expected if choices were random or governed by stereotyped visitation rules. We then exposed bees to either a high sub-lethal positive control thiamethoxam dose (2.5 ng(-1) bee), or one of two low doses (0.377 or 0.091 ng(-1)) based on estimated field-realistic exposure. The high dose caused bees to make more and earlier spatial memory errors and take longer to complete the task than unexposed bees. For the low doses, the negative effects were smaller but statistically significant, and dependent on bee size. The spatial working memory impairment shown here has the potential to harm bees exposed to thiamethoxam, through possible impacts on foraging efficiency or homing.

  20. Effect of pregabalin on fear-based conditioned avoidance learning and spatial learning in a mouse model of scopolamine-induced amnesia.

    Science.gov (United States)

    Sałat, Kinga; Podkowa, Adrian; Malikowska, Natalia; Trajer, Jędrzej

    2017-03-01

    Cognitive deficits are one of the frequent symptoms accompanying epilepsy or its treatment. In this study, the effect on cognition of intraperitoneally administered antiepileptic drug, pregabalin (10 mg/kg), was investigated in scopolamine-induced memory-impaired mice in the passive avoidance task and Morris water maze task. The effect of scopolamine and pregabalin on animals' locomotor activity was also studied. In the retention phase of the passive avoidance task, pregabalin reversed memory deficits induced by scopolamine (p learning in this task. During the probe trial a significant difference (p task, pregabalin reversed learning deficits induced by scopolamine. In the Morris water maze, pregabalin did not influence spatial learning deficits induced by scopolamine. These results are relevant for epileptic patients treated with pregabalin and those who use it for other therapeutic indications (anxiety, pain).

  1. A complex dietary supplement augments spatial learning, brain mass, and mitochondrial electron transport chain activity in aging mice

    OpenAIRE

    Aksenov, Vadim; Long, Jiangang; Liu, Jiankang; Szechtman, Henry; Khanna, Parul; Matravadia, Sarthak; Rollo, C. David

    2011-01-01

    We developed a complex dietary supplement designed to offset five key mechanisms of aging and tested its effectiveness in ameliorating age-related cognitive decline using a visually cued Morris water maze test. All younger mice (1 year) were unable to learn the maze even after 5 days, indicative of strong cognitive decline at older ages. In contrast, no cognitive decline was evident in older supplemented mice, even when ∼2 years old. Supplemented older mice were nearly 50% better at locating ...

  2. Social separation and diazepam withdrawal increase anxiety in the elevated plus-maze and serotonin turnover in the median raphe and hippocampus.

    Science.gov (United States)

    dos Santos, Lucinéia; de Andrade, Telma G C S; Graeff, Frederico G

    2010-05-01

    The present work aimed to evaluate the effects of social separation for 14 days (chronic stress) and of withdrawal from a 14-day treatment with diazepam (acute stress) on the exploratory behaviour of male rats in the elevated plus-maze and on serotonin (5-hydroxytryptamine) turnover in different brain structures. Social separation had an anxiogenic effect, evidenced by fewer entries into, and less time spent on the open arms of the elevated plus-maze. Separation also selectively increased 5-hydroxytryptamine turnover in the hippocampus and median raphe nucleus. Diazepam withdrawal had a similar anxiogenic effect in grouped animals and increased 5-hydroxytryptamine turnover in the same brain structures. Chronic treatment with imipramine during the 14 days of separation prevented the behavioural and neurochemical changes caused by social separation. It is suggested that the increase in anxiety determined by both acute and chronic stress is mediated by the activation of the median raphe nucleus-hippocampal 5-hydroxytryptamine pathway.

  3. The nitric oxide synthesis inhibitor L-NAME produces anxiogenic-like effects in the rat elevated plus-maze test, but not in the social interaction test.

    Science.gov (United States)

    Vale, A L; Green, S; Montgomery, A M; Shafi, S

    1998-01-01

    The effects of the nitric oxide synthase inhibitor, Nw-nitro-L-arginine methyl ester (L-NAME) were investigated in two animal models of anxiety: the elevated plus-maze and the social interaction test. In the elevated plus-maze, L-NAME (12.5-50 mg/kg) had an anxiogenic-like profile as indicated by dose-dependent reductions in the time spent on the open arms, open arm entries, the percentage of open arm entries and head dips, but there was no significant effect on the number of stretch attend postures. In contrast, L-NAME (12.5-50 mg/kg) failed to modify time spent in social interaction but did reduce a measure of vertical activity. The differential effects of L-NAME in the two anxiety paradigms are discussed.

  4. Latent learning in zebrafish (Danio rerio).

    Science.gov (United States)

    Gómez-Laplaza, Luis M; Gerlai, Robert

    2010-04-02

    The zebrafish may represent an excellent compromise between system complexity and practical simplicity for behavioral brain research. It may be particularly appropriate for large scale screening studies whose aim is to identify mutants with altered phenotypes or novel compounds with particular efficacy. For example, the zebrafish may have utility in the analysis of the biological mechanisms of learning and memory. Although learning and memory have been extensively studied and hundreds of underlying molecular mechanisms have been identified, this number may represent only the fraction of genes involved in these complex brain functions. Thus large scale mutagenesis screens may have utility. In order for such screens to succeed, appropriate screening paradigms must be developed. The first step in this research is the characterization of learning and memory capabilities of zebrafish and the development of automatable tasks. Here we show that zebrafish is capable of latent learning, i.e. can acquire memory of their environment after being allowed to explore it. For example, we found experimental zebrafish that experienced an open left tunnel or an open right tunnel of a maze during the unrewarded exploration phase of the test to show the appropriate side bias during a probe trial when they had to swim to a group of conspecifics (the reward). Given that exploration of the maze does not require the presence of the experimenter and the probe trial, during which the subjects are video-recorded and their memory is tested, is short, we argue that the paradigm has utility in high-throughput screening.

  5. Effects of essence of chicken on cognitive brain function: a near-infrared spectroscopy study.

    Science.gov (United States)

    Konagai, Chizuru; Watanabe, Hiroshi; Abe, Keiichi; Tsuruoka, Nobuo; Koga, Yoshihiko

    2013-01-01

    The aim of this study was to investigate the effects of the essence of chicken on brain function by near-infrared spectroscopy. Twelve healthy elderly subjects took the essence of chicken or a placebo for 7 d in a double-blind cross-over design study. Changes in oxy-hemoglobin concentrations in the bilateral prefrontal areas of the brain were measured while the subjects performed the simple reaction task, the Groton Maze Learning Test, and the working memory task. In the latter case, there were significant interactions in the changes in oxy-hemoglobin concentrations between treatment and period of intake according to two-way repeated ANOVA. The changes in oxy-hemoglobin concentrations significantly increased in several regions of the prefrontal areas of the brain in those taking essence of chicken for 7 d. These results suggest that essence of chicken is useful as a nutritional supplement to enhance or maintain brain function in the elderly.

  6. Dose-response effects of systemic anandamide administration in mice sequentially submitted to the open field and elevated plus-maze tests

    Directory of Open Access Journals (Sweden)

    A. Ribeiro

    2009-06-01

    Full Text Available The endocannabinoid system is involved in the control of many physiological functions, including the control of emotional states. In rodents, previous exposure to an open field increases the anxiety-like behavior in the elevated plus-maze. Anxiolytic-like effects of pharmacological compounds that increase endocannabinoid levels have been well documented. However, these effects are more evident in animals with high anxiety levels. Several studies have described characteristic inverted U-shaped dose-response effects of drugs that modulate the endocannabinoid levels. However, there are no studies showing the effects of different doses of exogenous anandamide, an endocannabinoid, in animal models of anxiety. Thus, in the present study, we determined the dose-response effects of exogenous anandamide at doses of 0.01, 0.1, and 1.0 mg/kg in C57BL/6 mice (N = 10/group sequentially submitted to the open field and elevated plus-maze. Anandamide was diluted in 0.9% saline, ethyl alcohol, Emulphor® (18:1:1 and administered ip (0.1 mL/10 g body weight; control animals received the same volume of anandamide vehicle. Anandamide at the dose of 0.1 mg/kg (but not of 0.01 or 1 mg/kg increased (P < 0.05 the time spent and the distance covered in the central zone of the open field, as well as the exploration of the open arms of the elevated plus-maze. Thus, exogenous anandamide, like pharmacological compounds that increase endocannabinoid levels, promoted a characteristic inverted U-shaped dose-response effect in animal models of anxiety. Furthermore, anandamide (0.1 mg/kg induced an anxiolytic-like effect in the elevated plus-maze (P < 0.05 after exposing the animals to the open field test.

  7. Dose-response effects of systemic anandamide administration in mice sequentially submitted to the open field and elevated plus-maze tests.

    Science.gov (United States)

    Ribeiro, A; Ferraz-de-Paula, V; Pinheiro, M L; Palermo-Neto, J

    2009-06-01

    The endocannabinoid system is involved in the control of many physiological functions, including the control of emotional states. In rodents, previous exposure to an open field increases the anxiety-like behavior in the elevated plus-maze. Anxiolytic-like effects of pharmacological compounds that increase endocannabinoid levels have been well documented. However, these effects are more evident in animals with high anxiety levels. Several studies have described characteristic inverted U-shaped dose-response effects of drugs that modulate the endocannabinoid levels. However, there are no studies showing the effects of different doses of exogenous anandamide, an endocannabinoid, in animal models of anxiety. Thus, in the present study, we determined the dose-response effects of exogenous anandamide at doses of 0.01, 0.1, and 1.0 mg/kg in C57BL/6 mice (N = 10/group) sequentially submitted to the open field and elevated plus-maze. Anandamide was diluted in 0.9% saline, ethyl alcohol, Emulphor (18:1:1) and administered ip (0.1 mL/10 g body weight); control animals received the same volume of anandamide vehicle. Anandamide at the dose of 0.1 mg/kg (but not of 0.01 or 1 mg/kg) increased (P open field, as well as the exploration of the open arms of the elevated plus-maze. Thus, exogenous anandamide, like pharmacological compounds that increase endocannabinoid levels, promoted a characteristic inverted U-shaped dose-response effect in animal models of anxiety. Furthermore, anandamide (0.1 mg/kg) induced an anxiolytic-like effect in the elevated plus-maze (P open field test.

  8. Evaluation of neurotransmitters involved in the anxiolytic and panicolytic effect of the aqueous fraction of Paullinia cupana (guaraná in elevated T maze

    Directory of Open Access Journals (Sweden)

    Marcel P. Rangel

    2013-04-01

    Full Text Available This study investigated the effects of repeatedly administration of an aqueous fraction of Paullinia cupana Kunth, Sapindaceae (guaraná seeds (8 mg/kg on rats submitted to the elevated T-maze, model of generalized anxiety and panic disorders. The selective serotonin reuptake inhibitor paroxetine (3 mg/kg, was used as a positive control. To evaluate possible neurotransmissions involvement, ineffective doses of metergoline (3 mg/kg - non-selective serotonin receptor antagonist, sulpiride (20 mg/kg - non-selective dopaminergic receptor antagonist or ketamine (0.125 mg/kg - non-selective glutamate receptor antagonist were acutely administered in association with the aqueous fraction of P. cupana. Both aqueous fraction and paroxetine decrease the inhibitory avoidance latencies of the elevated T-maze, indicating anxiolytic effect and increased one-way escape latencies from the open arm of the elevated T-maze, indicating a panicolytic effect. The pre-treatment with metergoline, sulpiride and ketamine blocked the anxiolytic effect of aqueous fraction. The panicolytic effect of aqueous fraction was blocked by both metergoline and sulpiride. These results show that the serotonergic, dopaminergic and glutamatergic neurotransmission systems are involved in anxiolytic effect promoted by aqueous fraction, whereas only the serotonergic and the dopaminergic neurotransmission systems are involved in the panicolytic effect promoted by aqueous fraction of P. cupana. The effects produced by paroxetine, were blocked only by metergoline, validating this experimental procedure.

  9. Higher detection sensitivity of anxiolytic effects of diazepam by ledge-free open arm with opaque walled closed arm elevated plus maze in male rats.

    Science.gov (United States)

    Horii, Yasuyuki; Kawaguchi, Maiko

    2015-11-01

    The elevated plus maze (EPM) is an established method for testing animal anxiety. However, EPM apparatuses and their features can differ among laboratories, most notably in the presence/absence of ledges on the open arm and/or the transparency/opaqueness of walls on the closed arm. The combined effects of these variable arm features on EPM behavior are not yet fully understood. In the present study, we prepared four types of EPM apparatus - open arms with (0.5 cm) or without (0 cm) ledges×closed arms with transparent or opaque walls - and compared the maze-exploration behavior of male Sprague-Dawley rats. We found that the presence of open arm ledges significantly increased the incidence of open arm exploration. Furthermore, time spent in the distal segment of the open arm was shortest in the apparatus that had open arms with no ledges and opaque closed arms (No-Ledges/Opaque), and was longest in the apparatus that had open arms with ledges and transparent closed arms (Ledges/Transparent). Additionally, the No-Ledges/Opaque apparatus could detect the effect of 0.5mg/kg diazepam, an anxiolytic drug, whereas the Ledges/Transparent apparatus could not. These results indicate that arm structure (features of both open and closed arms) significantly influences maze-exploratory behavior in rats, and that No-Ledges/Opaque apparatuses have higher detection sensitivity for anxiolytic effects of diazepam than that of Ledges/Transparent apparatuses.

  10. Baclofen prevents the elevated plus maze behavior and BDNF expression during naloxone precipitated morphine withdrawal in male and female mice.

    Science.gov (United States)

    Pedrón, Valeria T; Varani, André P; Balerio, Graciela N

    2016-05-01

    In previous studies we have shown that baclofen, a selective GABAB receptor agonist, prevents the somatic expression and reestablishes the dopamine and μ-opioid receptors levels, modified during naloxone-precipitated morphine withdrawal syndrome in male and female mice. There are no previous reports regarding sex differences in the elevated plus maze (EPM) and the expression of BDNF in morphine-withdrawn mice. The present study analyses the behavioral and biochemical variations during morphine withdrawal in mice of both sexes, and whether these variations are prevented with baclofen. Swiss-Webster albino prepubertal mice received morphine (2 mg/kg, i.p.) twice daily, for 9 consecutive days. On the 10th day, one group of morphine-treated mice received naloxone (opioid receptor antagonist; 6 mg/kg, i.p.) 1 h after the last dose of morphine to precipitate withdrawal. A second group received baclofen (2 mg/kg, i.p.) before naloxone administration. The EPM behavior was measured during 15 min after naloxone injection. The expression of BDNF-positive cells was determined by immunohistochemistry. Withdrawn male mice showed a higher percentage of time spent and number of entries to the open arms compared to withdrawn female mice. Baclofen prevented this behavior in both sexes. BDNF expression decreased in the AcbC, BNST, CeC, and CA3 of the hippocampus while increased in the BLA of morphine withdrawn male. Baclofen pretreatment prevented the BDNF expression observed in morphine withdrawn male mice in all the brain areas studied except in the CeC. Baclofen prevention of the EPM behavior associated to morphine withdrawal could be partially related to changes in BDNF expression.

  11. Influence of diltiazem on the behavior of zolpidem-treated mice in the elevated-plus maze test.

    Science.gov (United States)

    Cui, X-Y; Zhao, X; Chu, Q-P; Chen, B-Q; Zhang, Y-H

    2007-02-01

    The present study was undertaken to investigate the effect of diltiazem, a L-type calcium channel blocker (CCB), on the behavior of zolpidem-treated mice in the elevated plus-maze (EPM). Atypical benzodiazepine zolpidem significantly increased the percentage of open arm entries without influencing the total entries and total distance and average speed at the dose of 5 mg/kg (p.o.). Co-administration of zolpidem (2 mg/kg, p.o.) and diltiazem (5, 10 and 20 mg/kg, p.o.) significantly increased both the time spent and arm entries in the open arms without influencing the total entries and spontaneous activity notwithstanding that zolpidem at dose up to 2 mg/kg (p.o.) and diltiazem at dose up to 20 mg/kg (p.o.) did not show any effects on mice behavior in EPM. Zolpidem also attenuated the anxiogenic effect of 1-(3-Chlorophenyl)piperazine (mCPP, 0.7 mg/kg, i.p.) and 5-hydroxytryptophan (5-HTP, 30 mg/kg, i.p.). Even though the zolpidem at 1 mg/kg and diltiazem at 5 mg/kg were ineffective on mCPP-induced anxiety, respectively, the co-administration of zolpidem (1 mg/kg, i.p.) and diltiazem (5 mg/kg, p.o.) showed inhibitory effect on mCPP-induced anxiety in mice. These results suggested that diltiazem, a L-type CCB may augment the anxiolytic-like effect of zolpidem and also indicated that calcium channel modulation maybe involved in the anxiolytic-like properties of zolpidem.

  12. Low-dose nicotine facilitates spatial memory in ApoE-knockout mice in the radial arm maze.

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    Sultana, Ruby; Ameno, Kiyoshi; Jamal, Mostofa; Miki, Takanori; Tanaka, Naoko; Ono, Junichiro; Kinoshita, Hiroshi; Nakamura, Yu

    2013-06-01

    Here, we investigated the effects of nicotine on spatial memory in ApoE-knockout (ApoE-KO) and wild-type (WT) mice in a radial arm maze. Training occurred on three consecutive days and the test was performed on day 4, with one trial per day. Then on day 4, animals were administered nicotine (0.1, 0.25, 0.5, and 1.0 mg/kg) or the antagonist of nicotinic receptors (nAChRs) mecamylamine (MEC 2 mg/kg) alone or together with 0.1 mg/kg nicotine. The number of errors in the first eight choices was recorded. The results were that 0.1 mg/kg nicotine decreased errors in ApoE-KO mice, while 0.1 and 0.25 mg/kg nicotine reduced errors in WT mice, indicating that lower doses of nicotine elicit a memory improvement. In contrast, 1.0 mg/kg nicotine increased errors in WT mice, but not in ApoE-KO mice. MEC alone had no noticeable effect on errors in either strain of mice. However, co-administration of 0.1 mg/kg nicotine and MEC increased errors and reduced the effects of nicotine in WT mice, but not in ApoE-KO mice. Our study found a biphasic effect of nicotine in WT mice: it improves spatial memory at lower doses and impairs it at a higher dose. In ApoE-KO mice, nicotine improves memory at a low dose and has no effect at a higher dose, suggesting that the ApoE deficiency may influence the efficacy of nicotine. Moreover, a reversal of nicotinic effects with MEC was seen in WT mice, indicating the likelihood of the involvement of nAChRs in the spatial-memory response to nicotine.

  13. The Effects of Histaminergic Agents in the Nucleus ccumbens of Rats in the Elevated Plus-Maze Test of Anxiety

    Directory of Open Access Journals (Sweden)

    Ameneh Rezayof

    2010-05-01

    Full Text Available "n Objective: "n The nucleus accumbens (NAc receive histaminergic neurons from tuberomammillary nuclei. There are reports indicating that central histamine systems are involved in many physiological behavioral processes, including anxiety. The aim of the present study was to assess whether the histaminergic system of the NAc is involved in anxiety-related behaviors. Methods: Rats were anesthetized with intra-peritoneal injection of ketamine hydrochloride, plus xylazine and then were placed in a stereotaxic apparatus. In addition, two stainless-steel cannuale were placed 2 mm above the nucleus accumbens shell. Seven days after recovery from surgery, the behavioral testing was started. As a model of anxiety, the elevated plus maze which is a useful test to investigate the effects of anxiogenic or anxiolytic drugs in rodents, was used in male Wistar rats.  "nResults: Intra-NAc administration of histamine (0.01, 0.1 and 1 µg/rat increased the percentage of open arm time (%OAT and open arm entries (%OAE ,but not locomotor activity, indicating an anxiolytic response. Furthermore, bilateral  microinjections of different doses of the H1 receptor  antagonist pyrilamine (0.001, 0.01, 0.1 and 1 µg/rat or the H2 receptor antagonist ranitidine (0.001, 0.01, 0.1 and 1 µg/rat into the NAc increased %OAT and %OAE , but not locomotor activity. However, both histamine and histamine receptor antagonists showed an anxiolytic-like effect ; the antagonists (1 µg/rat also decreased the histamine response. "n "n Conclusion: The results may indicate a modulatory effect for the H1 and H2 histamine receptors of nucleus accumbens in the anxiety behavior of rats.

  14. Anxiolytic effects of a semipurified constituent of guaraná seeds on rats in the elevated T-maze test.

    Science.gov (United States)

    Roncon, Camila Marroni; Biesdorf de Almeida, Camila; Klein, Traudi; de Mello, João Carlos Palazzo; Audi, Elisabeth Aparecida

    2011-02-01

    The objective of this study was to investigate the effects of chronic administration of a semi-purified extract (Purified Extract A--PEA; 4, 8, or 16 mg/kg) of PAULLINIA CUPANA (guaraná) seeds on rats submitted to the elevated T-maze (ETM) model of generalized anxiety and panic disorders. The selective serotonin (5-HT) reuptake inhibitor (SSRI) paroxetine (PAR; 3 mg/kg), was used as a positive control. To evaluate possible serotonergic and dopaminergic neurotransmission involvement in the action of PEA during the ETM test, ineffective doses of metergoline (MET; 5-HT (2A/2C) antagonist receptor) or sulpiride (SUL; dopaminergic receptor antagonist) were acutely administered together with the PEA. The locomotion of the rats was assessed in a circular arena following each drug treatment. Both PEA (8 and 16 mg/kg) and PAR (3 mg/kg) increased one-way escape latencies from the open arm of the ETM, indicating a panicolytic effect compared to the control group. MET, in higher doses (1, 2 or 3 mg/kg), produced a panicolytic effect in the ETM test, whereas SUL did not (10, 20 or 40 mg/kg). The panicolytic effect produced by PEA (8 mg/kg) was blocked by both MET (2 mg/kg) and SUL (20 mg/kg), whereas the panicolytic effect produced by PAR (3 mg/kg) was blocked only by MET (2 mg/kg). These results show that chronic treatment with PEA produces a panicolytic effect during the ETM test, and that the dopaminergic and the serotonergic neurotransmission systems are involved in this effect.

  15. Comparative studies using the Morris water maze to assess spatial memory deficits in two transgenic mouse models of Alzheimer's disease.

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    Edwards, Stephen R; Hamlin, Adam S; Marks, Nicola; Coulson, Elizabeth J; Smith, Maree T

    2014-10-01

    Evaluation of the efficacy of novel therapeutics for potential treatment of Alzheimer's disease (AD) requires an animal model that develops age-related cognitive deficits reproducibly between independent groups of investigators. Herein we assessed comparative temporal changes in spatial memory function in two commercially available transgenic mouse models of AD using the Morris water maze (MWM), incorporating both visible and hidden platform training. Individual cohorts of cDNA-based 'line 85'-derived double-transgenic mice coexpressing the 'Swedish' mutation of amyloid precursor protein (APPSwe) and the presenillin 1 (PS1) 'dE9' mutation were assessed in the MWM at mean ages of 3.6, 9.3 and 14.8 months. We found significant deficits in spatial memory retention in APPSwe/PS1dE9 mice aged 3.6 months and robust deficits in spatial memory acquisition and retention in APPSwe/PS1dE9 mice aged 9.3 months, with a further significant decline by age 14.8 months. β-Amyloid deposits were present in brain sections by 7.25 months of age. In contrast, MWM studies with individual cohorts (aged 4-21 months) of single-transgenic genomic-based APPSwe mice expressing APPSwe on a yeast artificial chromosomal (YAC) construct showed no significant deficits in spatial memory acquisition until 21 months of age. There were no significant deficits in spatial memory retention up to 21 months of age and β-amyloid deposits were not present in brain sections up to 24 months of age. These data, generated using comprehensive study designs, show that APPSwe/PS1dE9 but not APPSwe YAC mice appear to provide a suitably robust model of AD for efficacy assessment of novel AD treatments in development.

  16. The blockage of ventromedial hypothalamus CRF type 2 receptors impairs escape responses in the elevated T-maze.

    Science.gov (United States)

    Silva, Mariana S C F; Souza, Thaissa M O; Pereira, Bruno A; Ribeiro, Daniel A; Céspedes, Isabel C; Bittencourt, Jackson C; Viana, Milena B

    2017-06-30

    In a previous study, the administration of corticotrophin-releasing factor (CRF) into the dorsomedial hypothalamus (DMH), a region that modulates defensive reactions, was shown to facilitate elevated T-maze (ETM) avoidance responses, an anxiogenic-like effect. Intra-DMH administration of the CRF type 1 receptor (CRFR1) antagonist antalarmin induced anxiolytic-like effects and counteracted the anxiogenic effects of CRF. The present study further investigates the role played by CRF receptors of the medial hypothalamus in anxiety. For that, male wistar rats were treated with CRFR1 and CRFR2-modulating drugs in the DMH or VMH, another hypothalamic nucleus implicated with defensive and emotional behavior, and tested in the ETM for inhibitory avoidance and escape measurements. In clinical terms, these responses have been respectively related to generalized anxiety and panic disorder. All animals were tested in an open field, immediately after the ETM, for locomotor activity assessment. The results showed that intra-VMH CRF or antalarmin did not alter ETM avoidance or escape performance. Intra-VMH injection of the CRFR2 preferential antagonist antisauvagine-30 or of the selective CRFR2 antagonist astressin 2-B inhibited escape performance, a panicolytic-like effect, without altering avoidance reactions. The CRFR2 agonist urocortin-2 intra-VMH was by itself without effect but blocked the effects of astressin 2-B. None of the drugs administered into the DMH altered ETM measurements. Additionally, none of the compounds altered locomotor activity measurements. These results suggest that VMH CRFR2 modulate a defensive response associated with panic disorder and are of relevance to the better understanding of the neural mechanisms underlying this pathological condition. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Effects of BNST lesions in female rats on forced swimming and navigational learning.

    Science.gov (United States)

    Pezuk, Pinar; Aydin, Elif; Aksoy, Ayla; Canbeyli, Resit

    2008-09-01

    The bed nucleus of the stria terminalis (BNST) in the forebrain shows sexual dimorphism in its neuroanatomical connectivity and neurochemical characteristics. The structure is involved in many behavioral and motivational phenomena particularly related to coping with stress. Female rats differ from males in responding to stressful situations such as forced swimming and navigational learning in the water maze. It was previously shown that bilateral damage to the BNST in male Wistar rats aggravated depression as measured by forced swim tests, but did not impair navigational learning in the water maze. The present study extended the findings to female rats demonstrating that bilateral electrolytic lesions of the BNST increased immobility and decreased climbing compared to sham-operated controls, but failed to affect performance in the water maze. Additionally, lesions did not alter behavior in the open field and the elevated plus-maze tests suggesting not only that the modulation of depression by BNST lesions is specific, but also providing support for the view that the BNST may not necessarily be critically involved in anxiety.

  18. Effects of Xanthoceraside on learning and memory impairment in mice induced by i.c.v. Aβ1-42

    Institute of Scientific and Technical Information of China (English)

    ZOU Li-bo; CHI Tian-yan; ZHAO Hong-yun; LI Xiao-chun; WANG Li-hua; YANG Bai-zhen

    2008-01-01

    Objective To investigate the improvement of Xanthoceraside on learning and memory impairment in mice induced by intracerebroventricular injection of Aβ1-42 (i. c. v. Aβ1-42)and the possible mechanisms of its protection against AD. Methods Y-maze test, water-maze test and step-down test were used to investigate the learning and memory ability of mice;Biochemical analysis was used to detect the activity of CAT, T-AOC, ATPase and the content of MDA. Results The results showed that Xanthoceraside could significandy increase the alternation behavior in Y-maze test, shorten swimming time in water maze test and increase the latency and decrease the number of errors and the total time of shock in step-down test. Xanthoceraside markedly increased the activity of CAT, T-AOC, ATPase, at the same time, decreased the content of MDA. Conclusions Xanthoceraside can improve learning and memory impairment in mice induced by i.c.v.Aβ1-42 significantly. The mechanism may be associated with the protection against damage induced by free radicals; the inhibition of membrane lipid peroxidation and the improvement of metabolism of brain.

  19. Music during learning of a tactual-spatial task affects later response generalization.

    Science.gov (United States)

    McFarland, R A; Hanna, K; Kadish, R; Kennison, R F; Bush, S; Bowd, C

    1990-10-01

    Equal numbers of men and women learned a finger maze, with half of the subjects initially using their right hands and the other half using their left hands. To reach criterion, subjects receiving music in the ear ipsilateral to the hand used required more trials than did those receiving no music. Furthermore, when the right hand ran the maze, music played to the ipsilateral ear also delayed learning, compared with music played contralaterally. Binaural music delayed learning when the left hand was used but not when the right hand was used. Possible causes of these effects are suggested. When subjects switched hands and relearned the maze, the number of trials to criterion depended on the group subjects were in during initial learning and not on the group they were in during the hand reversal (response generalization) trials. Although the music condition used determined the effect of music on initial learning and on response generalization, some evidence is presented that indicates that the two effects are not entirely interdependent and that they may even involve different mechanisms.

  20. Repeated morphine treatment influences operant and spatial learning differentially

    Institute of Scientific and Technical Information of China (English)

    Mei-Na WANG; Zhi-Fang DONG; Jun CAO; Lin XU

    2006-01-01

    Objective To investigate whether repeated morphine exposure or prolonged withdrawal could influence operant and spatial learning differentially. Methods Animals were chronically treated with morphine or subjected to morphine withdrawal. Then, they were subjected to two kinds of learning: operant conditioning and spatial learning.Results The acquisition of both simple appetitive and cued operant learning was impaired after repeated morphine treatment. Withdrawal for 5 weeks alleviated the impairments. Single morphine exposure disrupted the retrieval of operant memory but had no effect on rats after 5-week withdrawal. Contrarily, neither chronic morphine exposure nor 5-week withdrawal influenced spatial learning task of the Morris water maze. Nevertheless, the retrieval of spatial memory was impaired by repeated morphine exposure but not by 5-week withdrawal. Conclusion These observations suggest that repeated morphine exposure can influence different types of learning at different aspects, implicating that the formation of opiate addiction may usurp memory mechanisms differentially.

  1. Solution to reinforcement learning problems with artificial potential field

    Institute of Scientific and Technical Information of China (English)

    XIE Li-juan; XIE Guang-rong; CHEN Huan-wen; LI Xiao-li

    2008-01-01

    A novel method was designed to solve reinforcement learning problems with artificial potential field. Firstly a reinforcement learning problem was transferred to a path planning problem by using artificial potential field(APF), which was a very appropriate method to model a reinforcement learning problem. Secondly, a new APF algorithm was proposed to overcome the local minimum problem in the potential field methods with a virtual water-flow concept. The performance of this new method was tested by a gridworld problem named as key and door maze. The experimental results show that within 45 trials, good and deterministic policies are found in almost all simulations. In comparison with WIERING's HQ-learning system which needs 20 000 trials for stable solution, the proposed new method can obtain optimal and stable policy far more quickly than HQ-learning. Therefore, the new method is simple and effective to give an optimal solution to the reinforcement learning problem.

  2. The Leidenfrost Maze

    Science.gov (United States)

    Cheng, Carmen; Guy, Matthew; Narduzzo, Alessandro; Takashina, Kei

    2015-05-01

    Recent research into applications of the Leidenfrost effect have sparked renewed interest for this phenomenon. We report here on some of these developments, and on their deployment in an undergraduate teaching project that culminated in the production of a viral internet video. We analyse the key ingredients to the project’s apparent success, both in terms of physics pedagogy and outreach/public engagement.

  3. 论游泳训练对不同性别大鼠Morris 水迷宫测试成绩的影响%Influence of Swimming Training on Mature Rats of Different Genders in the Test of Morris Water Maze

    Institute of Scientific and Technical Information of China (English)

    潘华; 李强

    2012-01-01

    利用定位航行实验和空间探索实验在Morris水迷宫中对雄性、雌性大鼠进行为期9周的游泳训练,实验结果显示:游泳训练能显著提高雄性、雌性大鼠的学习和记忆能力,但雄性大鼠学习和记忆的能力优于雌性大鼠.%By means of place navigation test and spatial probe test in swimming Morris water maze on mature rats. The results show that swimming training can improve the rats' abilities to learn and to memorize. The male rats, however, prove superior to female ones in such abilities.

  4. The Function of the Glutamate-Nitric Oxide-cGMP Pathway in Brain in Vivo and Learning Ability Decrease in Parallel in Mature Compared with Young Rats

    Science.gov (United States)

    Piedrafita, Blanca; Cauli, Omar; Montoliu, Carmina; Felipo, Vicente

    2007-01-01

    Aging is associated with cognitive impairment, but the underlying mechanisms remain unclear. We have recently reported that the ability of rats to learn a Y-maze conditional discrimination task depends on the function of the glutamate-nitric oxide-cGMP pathway in brain. The aims of the present work were to assess whether the ability of rats to…

  5. Combined neonatal stress and young-adult glucocorticoid stimulation in rats reduce BDNF expression in hippocampus: effects on learning and memory.

    Science.gov (United States)

    Choy, Kwok Ho Christopher; de Visser, Yvonne; Nichols, Nancy R; van den Buuse, Maarten

    2008-01-01

    Epidemiological studies suggest that multiple developmental disruptions are involved in the etiology of psychiatric illnesses including schizophrenia. In addition, altered expression of brain-derived neurotrophic factor (BDNF) has been implicated in these illnesses. In the present study, we examined the combined long-term effect of an early stress, in the form of maternal deprivation, and a later stress, simulated by chronic young-adult treatment with the stress hormone, corticosterone, on BDNF expression in the hippocampus of rats. To assess whether there were behavioral effects, which may correlate with the BDNF changes, learning and memory was tested in the Y-maze test for short term spatial memory, the Morris water maze for long-term spatial memory, and the T-maze test for working memory. Four groups of rats received either no stress, maternal deprivation, corticosterone treatment, or both. Dorsal hippocampus sections obtained from parallel groups were used for BDNF mRNA in situ hybridization. Rats which had undergone both maternal deprivation and corticosterone treatment displayed a unique and significant 25-35% reduction of BDNF expression in the dentate gyrus (DG), and similar trends in the CA1 and CA3 regions of the hippocampus. These "two-hit" animals exhibited a learning delay in the Morris water maze test, a marked deficit in the Y-maze, but little change in the T-maze test. However, some aspects of cognition were also altered in rats with either maternal deprivation or corticosterone treatment. This study demonstrates a persistent effect of two developmental disruptions on BDNF expression in the hippocampus, with parallel, but not completely correlative changes in learning and memory.

  6. NF-kappaB activity affects learning in aversive tasks: possible actions via modulation of the stress axis.

    Science.gov (United States)

    Lehmann, Michael L; Brachman, Rebecca A; Listwak, Samuel J; Herkenham, Miles

    2010-08-01

    The role of altered activity of nuclear factor kappaB (NF-kappaB) in specific aspects of motivated behavior and learning and memory was examined in mice lacking the p50 subunit of the NF-kappaB/rel transcription factor family. Nfkb1-deficient mice are unable to produce p50 and show specific susceptibilities to infections and inflammatory challenges, but the behavioral phenotype of such mice has been largely unexamined, owing in large part to the lack of understanding of the role of NF-kappaB in nervous system function. Here we show that Nfkb1 (p50) knockout mice more rapidly learned to find the hidden platform in the Morris water maze than did wildtype mice. The rise in plasma corticosterone levels after the maze test was greater in p50 knockout than in wildtype mice. In the less stressful Barnes maze, which tests similar kinds of spatial learning, the p50 knockout mice performed similarly to control mice. Adrenalectomy with corticosterone replacement eliminated the differences between p50 knockout and wildtype mice in the water maze. Knockout mice showed increased levels of basal anxiety in the open-field and light/dark box tests, suggesting that their enhanced escape latency in the water maze was due to activation of the stress (hypothalamic-pituitary-adrenal) axis leading to elevated corticosterone production by strongly but not mildly anxiogenic stimuli. The results suggest that, as in the immune system, p50 in the nervous system normally serves to dampen NF-kappaB-mediated intracellular activities, which are manifested physiologically through elevated stress responses to aversive stimuli and behaviorally in the facilitated escape performance in learning tasks.

  7. Paradoxical increase of exploratory behavior in the elevated plus-maze by rats exposed to two kinds of aversive stimuli

    Directory of Open Access Journals (Sweden)

    Morato S.

    1997-01-01

    Full Text Available Albino rats were submitted to a 24-h period of social isolation (individual housing combined with 0, 1, 2 or 3 twenty-four-hour periods of exposure to different vivaria (novelty and tested in the elevated plus-maze. Results, reported as mean ± SEM for N = 12, show that the time (in seconds spent in the open arms by rats exposed to novelty for 0, 1, 2 and 3 days was 28.3 ± 4.4, 31.6 ± 3.2, 29.1 ± 3.5 and 25.0 ± 3.3, respectively, when grouped in the same vivarium; 29.6 ± 2.7, 7.6 ± 2.1, 9.6 ± 4.4 and 28.5 ± 3.7 when grouped in different vivaria; 2.9 ± 1.1, 1.8 ± 1.0, 2.7 ± 1.1 and 0 ± 0 when isolated in the same vivarium, and 2.6 ± 1.1, 31.5 ± 8.2, 24.8 ± 4.2 and 0 ± 0 when isolated in different vivaria. The number of entries into the open and closed arms followed a similar trend. This indicates that, separately, both exposure to novelty and isolation are aversive manipulations. Paradoxically, when novelty was combined with a concomitant 24-h period of social isolation prior to testing, the decrease in exploratory behavior caused by either of the two aversive manipulations alone was reverted. These results are indicative that less intense anxiety triggers mechanisms mediating less energetic behavior such as freezing, while higher levels trigger mechanisms mediating more vigorous action, such as flight/fight behavior, since the combination of two aversive situations resulted in more exploratory behavior than with either alone. They are also suggestive of habituation to the effects of novelty, since exposure to it for 3 days produced exploratory behavior similar to that of controls

  8. Reactivation of an aversive memory modulates learning strategy preference in male rats.

    Science.gov (United States)

    Hawley, Wayne R; Grissom, Elin M; Patel, Jessica M; Hodges, Kelly S; Dohanich, Gary P

    2013-01-01

    Reminders of an aversive event adversely impact retrieval of hippocampus-dependent memories and exacerbate stress-induced levels of anxiety. Interestingly, stress and anxiety shift control over learning away from the hippocampus and toward the striatum. The aims of the current study were to determine whether spatial memory and learning strategy are impacted by reminders of a stressor. Adult male Long-Evans rats (N = 47) were subjected to an inhibitory avoidance (IA) training trial in which 32 rats were exposed (3 s) to a single inescapable electrical footshock (0.6 mA). Prior to the retention trial of a Y-maze task and the probe trials of two different learning strategy tasks, some of the rats that were exposed to the footshock (n = 17) were reminded of the stressor on an IA retrieval trial. Both groups of rats exposed to the initial stressor exhibited hypoactivity, but no impairment in spatial memory, on the Y-maze task conducted 1 week after exposure to the footshock. One month after exposure to footshock, both groups of rats exposed to the initial stressor tended to prefer a striatum-dependent learning strategy on a water T-maze task. However, 2 months after exposure to footshock, only shocked rats that were reminded of the stressor exhibited a preference for a striatum-dependent learning strategy on a visible-platform water maze task, which corresponded with lower levels of activity in an open field. The results indicate that reminders of a stressor perpetuate the deleterious effects of stress on affective and cognitive processes.

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

    Science.gov (United States)

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

    2017-03-15

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

  10. Retrieval of Consolidated Spatial Memory in the Water Maze Is Correlated with Expression of pCREB and Egr1 in the Hippocampus of Aged Mice

    Directory of Open Access Journals (Sweden)

    GuoXia Zhou

    2013-02-01

    Full Text Available Objective: To study the relationship of the expression of phosphorylated cyclic AMP response element-binding protein (pCREB and early growth response protein 1 (Egr1 in the hippocampus of aged mice with retrieval of consolidated spatial memory in a water maze. Methods: Twenty-four aged mice were allocated into no training or probe test (naïve, no training but exposed to the same probe test (NTPRT, received training and probe test (PRT, and received training but no probe test (NPRT groups. Twelve mice were trained in a water maze over 14 days. After the final probe trial on day 15, all mice were anesthetized and the brains were removed. pCREB immunoreactivity (pCREB-ir and Egr1 immunoreactivity (Egr1-ir in the hippocampal CA1 and CA3 areas were examined. Results: pCREB-ir and Egr1-ir in the CA1 and CA3 areas of the NPRT and PRT groups were significantly higher than those of the naïve and NTPRT groups, and those in the PRT group were significantly higher than in the NPRT group. In all groups, pCREB-ir was significantly higher in the CA3 area compared to the CA1 area, while Egr1-ir was significantly higher in the CA1 area compared to the CA3 area. Conclusion: Retrieval, as well as formation, of consolidated spatial memory in the water maze is correlated with expression of pCREB and Egr1 in the hippocampus of aged mice.

  11. PWZ-029, an inverse agonist selective for α₅ GABAA receptors, improves object recognition, but not water-maze memory in normal and scopolamine-treated rats.

    Science.gov (United States)

    Milić, Marija; Timić, Tamara; Joksimović, Srđan; Biawat, Poonam; Rallapalli, Sundari; Divljaković, Jovana; Radulović, Tamara; Cook, James M; Savić, Miroslav M

    2013-03-15

    Inverse agonism at the benzodiazepine site of α(5) subunit-containing GABA(A) receptors is an attractive approach for the development of putative cognition-enhancing compounds, which are still far from clinical application. Several ligands with binding and/or functional selectivity for α(5) GABA(A) receptors have been synthesized and tested in a few animal models. PWZ-029 is an α(5) GABA(A) selective inverse agonist whose memory enhancing effects were demonstrated in the passive avoidance task in rats and in Pavlovian fear conditioning in mice. In the present study we investigated the effects of PWZ-029 administration in novel object recognition test and Morris water maze, in normal and scopolamine-treated rats. All the three doses of PWZ-029 (2, 5 and 10 mg/kg) improved object recognition after the 24-h delay period, as shown by significant differences between the exploration times of the novel and old object, and the respective discrimination indices. PWZ-029 (2 mg/kg) also successfully reversed the 0.3 mg/kg scopolamine-induced deficit in recognition memory after the 1-h delay. In the Morris water maze test, PWZ-029 (5, 10 and 15 mg/kg) did not significantly influence swim patterns, either during five acquisition days or during the treatment-free probe trial. PWZ-029 (2, 5 and 10 mg/kg) also proved to be ineffective in the reversal of the 1mg/kg scopolamine-induced memory impairment in the water maze. The present mixed results encourage use of a variety of tests and experimental conditions in order to increase the predictability of preclinical testing of selective α(5) GABA(A) inverse agonists.

  12. An automated Y-maze based on a reduced instruction set computer (RISC) microcontroller for the assessment of continuous spontaneous alternation in rats.

    Science.gov (United States)

    Heredia-López, Francisco J; Álvarez-Cervera, Fernando J; Collí-Alfaro, José G; Bata-García, José L; Arankowsky-Sandoval, Gloria; Góngora-Alfaro, José L

    2016-12-01

    Continuous spontaneous alternation behavior (SAB) in a Y-maze is used for evaluating working memory in rodents. Here, the design of an automated Y-maze equipped with three infrared optocouplers per arm, and commanded by a reduced instruction set computer (RISC) microcontroller is described. The software was devised for recording only true entries and exits to the arms. Experimental settings are programmed via a keyboard with three buttons and a display. The sequence of arm entries and the time spent in each arm and the neutral zone (NZ) are saved as a text file in a non-volatile memory for later transfer to a USB flash memory. Data files are analyzed with a program developed under LabVIEW® environment, and the results are exported to an Excel® spreadsheet file. Variables measured are: latency to exit the starting arm, sequence and number of arm entries, number of alternations, alternation percentage, and cumulative times spent in each arm and NZ. The automated Y-maze accurately detected the SAB decrease produced in rats by the muscarinic antagonist trihexyphenidyl, and its reversal by caffeine, having 100 % concordance with the alternation percentages calculated by two trained observers who independently watched videos of the same experiments. Although the values of time spent in the arms and NZ measured by the automated system had small discrepancies with those calculated by the observers, Bland-Altman analysis showed 95 % concordance in three pairs of comparisons, while in one it was 90 %, indicating that this system is a reliable and inexpensive alternative for the study of continuous SAB in rodents.

  13. Effects of lithium and carbamazepine on spatial learning and depressive behavior in a rat model of bipolar disorder induced by ouabain.

    Science.gov (United States)

    Wang, Ying-Chou; Wang, En-Nan; Wang, Chia-Chuan; Huang, Chung-Lei; Huang, Andrew Chih Wei

    2013-04-01

    Lithium (LiCl) and carbamazepine (CBZ), the common mood stabilizers, are thought to be effective treatments for bipolar disorder. The aim of the present study was to investigate whether LiCl as well as CBZ has similar effects on the bipolar disorder-associated cognitive dysfunctions in rats, particularly the spatial learning and depressive responses. Adult male Wistar rats were administered intracerebroventricularly with 5μl of 10(-3)M ouabain on session 1, and then received an intraperitoneal injection of LiCl or CBZ for 4 sessions (1 session/2days). For the behavioral tests, all rats were subjected to the water maze 15min for spatial learning and the forced swimming test 5min for depression on each session. The present results showed that ouabain resulted in increased latency and longer distance traveled to reach the hidden platform in the water maze, indicating that ouabain impaired the spatial learning. However, ouabain did not affect swimming velocity in the water maze and depressive responses in the forced swimming test. LiCl treatment decreased the ouabain-enhanced latency and the total distance, but not the velocity, swam to reach the hidden platform in the water maze task. Additionally, LiCl did not result in changes of any depressive indices, such as struggling behavior, swimming behavior, and floating behavior. Likewise, CBZ did not affect any behavioral indices of spatial learning and depression. A linear regression analysis suggested that LiCl, but not CBZ, could predict the decreased latency and total distance traveled except the velocity of swimming in the water maze and depressive behaviors. In summary, the present results suggested that lithium provided a better therapeutic effect than CBZ for ouabain-caused dysfunctions of spatial learning in a rat model of bipolar disorder. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  14. Anesthetic Considerations for a Patient With Hereditary Hemorrhagic Telangiectasia (Osler–Weber–Rendu Syndrome Undergoing a Five-Box Thoracoscopic Maze Procedure for Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Dominic Robinson DO

    2014-10-01

    Full Text Available Hereditary hemorrhagic telangiectasia (HHT is an autosomal dominant genetic disorder involving the abnormal communication of vascular structures. HHT typically presents with recurrent epistaxis and telangiectasis of the nasal and buccal mucosa, tongue, and lips. More serious manifestations of this disease include cerebral, pulmonary, gastrointestinal, and hepatic arteriovenous malformations. This case report details a 55-year-old male with HHT undergoing a five-box maze procedure for curative treatment of atrial fibrillation. Particular anesthetic considerations are described to reduce morbidity and mortality in this patient population.

  15. Escape and avoidance learning in the earthworm Eisenia hortensis

    Directory of Open Access Journals (Sweden)

    W. Jeffrey Wilson

    2014-01-01

    Full Text Available Interest in instrumental learning in earthworms dates back to 1912 when Yerkes concluded that they can learn a spatial discrimination in a T-maze. Rosenkoetter and Boice determined in the 1970s that the “learning” that Yerkes observed was probably chemotaxis and not learning at all. We examined a different form of instrumental learning: the ability to learn both to escape and to avoid an aversive stimulus. Freely moving “master” worms could turn off an aversive white light by increasing their movement; the behavior of yoked controls had no effect on the light. We demonstrate that in as few as 12 trials the behavior of the master worms comes under the control of this contingency.

  16. Effect of botanical extracts containing carnosic acid or rosmarinic acid on learning and memory in SAMP8 mice.

    Science.gov (United States)

    Farr, Susan A; Niehoff, Michael L; Ceddia, Michael A; Herrlinger, Kelli A; Lewis, Brandon J; Feng, Shulin; Welleford, Andrew; Butterfield, D Allan; Morley, John E

    2016-10-15

    Oxidative damage is one of the hallmarks of the aging process. The current study evaluated effects of two proprietary antioxidant-based ingredients, rosemary extract and spearmint extract containing carnosic acid and rosmarinic acid, respectively, on learning and memory in the SAMP8 mouse model of accelerated aging. The two rosemary extracts contained carnosic acid (60% or 10% carnosic acid) and one spearmint extract contained 5% rosmarinic acid. Three doses of actives in each extract were tested: 32, 16, 1.6 or 0mg/kg. After 90days of treatment mice were tested in T-maze foot shock avoidance, object recognition and lever press. Rosemary extract containing 60% carnosic acid improved acquisition and retention in T-maze foot shock, object recognition and lever press. Rosemary extract with 10% carnosic acid improved retention in T-maze foot shock avoidance and lever press. Spearmint with 5% rosmarinic acid improved acquisition and retention in T-maze foot shock avoidance and object recognition. 4-hydroxynonenal (HNE) was reduced in the brain cortex after treatment with all three extracts (P<0.001) compared to the vehicle treated SAMP8. Protein carbonyls were reduced in the hippocampus after administration of rosemary with 10% carnosic acid (P<0.05) and spearmint containing 5% rosmarinic acid (P<0.001). The current results indicate that the extracts from spearmint and rosemary have beneficial effects on learning and memory and brain tissue markers of oxidation that occur with age in SAMP8 mice.

  17. Low-dose thioperamide injected into the cerebellar vermis of mice immediately after exposure to the elevated plus-maze impairs their avoidance behavior on re-exposure to the apparatus

    Directory of Open Access Journals (Sweden)

    J. Costa Neto

    2013-11-01

    Full Text Available The present study investigated the effect of thioperamide (THIO, an H3 histaminergic receptor antagonist, microinjected into the cerebellar vermis on emotional memory consolidation in male Swiss albino mice re-exposed to the elevated plus-maze (EPM. We implanted a guide cannula into the cerebellar vermis using stereotactic surgery. On the third day after surgery, we performed behavioral tests for two consecutive days. On the first day (exposure, the mice (n=10/group were exposed to the EPM and received THIO (0.06, 0.3, or 1.5 ng/0.1 µL immediately after the end of the session. Twenty-four hours later, the mice were re-exposed to the EPM under the same experimental conditions, but without drug injection. A reduction in the exploration of the open arms upon re-exposure to the EPM (percentage of number of entries and time spent in open arms compared with the initial exposure was used as an indicator of learning and memory. One-way analysis of variance (ANOVA followed by the Duncan post hoc test was used to analyze the data. Upon re-exposure, exploratory activity in the open arms was reduced in the control group, and with the two highest THIO doses: 0.3 and 1.5 ng/0.1 µL. No reduction was seen with the lowest THIO dose (0.06 ng/0.1 µL, indicating inhibition of the consolidation of emotional memory. None of the doses interfered with the animals' locomotor activity. We conclude that THIO at the lowest dose (0.06 ng/0.1 µL microinjected into the cerebellum impaired emotional memory consolidation in mice.

  18. GR3027 antagonizes GABAA receptor-potentiating neurosteroids and restores spatial learning and motor coordination in rats with chronic hyperammonemia and hepatic encephalopathy.

    Science.gov (United States)

    Johansson, Maja; Agusti, Ana; Llansola, Marta; Montoliu, Carmina; Strömberg, Jessica; Malinina, Evgenya; Ragagnin, Gianna; Doverskog, Magnus; Bäckström, Torbjörn; Felipo, Vicente

    2015-09-01

    Hepatic encephalopathy (HE) is one of the primary complications of liver cirrhosis. Current treatments for HE, mainly directed to reduction of ammonia levels, are not effective enough because they cannot completely eliminate hyperammonemia and inflammation, which induce the neurological alterations. Studies in animal models show that overactivation of GABAA receptors is involved in cognitive and motor impairment in HE and that reducing this activation restores these functions. We have developed a new compound, GR3027, that selectively antagonizes the enhanced activation of GABAA receptors by neurosteroids such as allopregnanolone and 3α,21-dihydroxy-5α-pregnan-20-one (THDOC). This work aimed to assess whether GR3027 improves motor incoordination, spatial learning, and circadian rhythms of activity in rats with HE. GR3027 was administered subcutaneously to two main models of HE: rats with chronic hyperammonemia due to ammonia feeding and rats with portacaval shunts (PCS). Motor coordination was assessed in beam walking and spatial learning and memory in the Morris water maze and the radial maze. Circadian rhythms of ambulatory and vertical activity were also assessed. In both hyperammonemic and PCS rats, GR3027 restores motor coordination, spatial memory in the Morris water maze, and spatial learning in the radial maze. GR3027 also partially restores circadian rhythms of ambulatory and vertical activity in PCS rats. GR3027 is a novel approach to treatment of HE that would normalize neurological functions altered because of enhanced GABAergic tone, affording more complete normalization of cognitive and motor function than current treatments for HE.

  19. Hippocampal lesions in rats impair learning and memory for locations on a touch-sensitive computer screen: the "ASAT" task.

    Science.gov (United States)

    Talpos, J C; Dias, R; Bussey, T J; Saksida, L M

    2008-10-10

    It has been repeatedly demonstrated across species that the hippocampus is critical for spatial learning and memory. Consequently, numerous paradigms have been created to study spatial learning in the rodent. Most of these tasks, such as the Morris water maze, 8-arm radial maze, and T-maze, are non-automated procedures. It was our goal to create an automated task in the rodent that is quickly learned, hippocampal-dependent, and minimizes the confounding variables present in most tests measuring hippocampal-dependent learning and memory. To accomplish this, we created a novel search task using a standard operant box fitted with a touch-sensitive computer monitor. Subjects were required to locate an S+ "hidden" amongst other identical stimuli on the monitor. In two versions of the task the S+ stayed in the same location within a session but shifted location between sessions. In a third version of the task the S+ was moved to a new location after every 10 trials. It was found that the location of the S+ was quickly acquired each day (within 10 trials), and that the hippocampal-lesion group was impaired when compared to their control cohort. With the benefits inherent in automation, these tasks confer significant advantages over traditional tasks used to study spatial learning and memory in the rodent. When combined with previously developed non-spatial cognitive tests that can also be run in the touch-screen apparatus, the result is a powerful cognitive test battery for the rodent.

  20. Regional differences in hippocampal PKA immunoreactivity after training and reversal training in a spatial Y-maze task

    NARCIS (Netherlands)

    Havekes, Robbert; Timmer, Marjan; Van der Zee, Eddy A.

    2007-01-01

    It is suggested that the hippocampus functions as a comparator by making a comparison between the internal representation and actual sensory information from the environment (for instance, comparing a previously learned location of a food reward with an actual novel location of a food reward in a Y-

  1. The effect of subacute supplementation of taurine on spatial learning and memory.

    Science.gov (United States)

    Ito, Koichi; Arko, Matevz; Kawaguchi, Tomohiro; Kuwahara, Masayoshi; Tsubone, Hirokazu

    2009-04-01

    Although the effect of taurine on the heart and liver is well studied, there has been no direct observation concerning the effect of taurine on spatial learning and memory at the behavior level. In this study, we tested the effect of subacute taurine supplementation with evaluation by the Morris water maze method. Although swim distance to find the platform of taurine-supplemented rats was significantly longer than that of control rats due to increase of swimming velocity, escape latency and the efficacy of learning and memory was comparable in both groups. These results suggest that taurine supplemented orally does not affect the learning and memory function.

  2. [Effects of nootropic drugs on behavior of BALB/c and C57BL/6 mice in the exploratory cross-maze test].

    Science.gov (United States)

    Vasil'eva, E V; Salimov, R M; Kovalev, G I

    2012-01-01

    Exploratory behavior, locomotor activity, and anxiety in inbred mice of C57BL/6 and BALB/c strains subchronically treated with placebo or various types of nootropic (cognition enhancing) drugs (piracetam, phenotropil, noopept, semax, pantogam, nooglutil) have been evaluated using the exploratory cross-maze test. It was found that BALB/c mice in comparison to C57BL/6 mice are characterized by greater anxiety and lower efficiency of exploratory behavior in the previously unfamiliar environment. All tested drugs clearly improved the exploratory behavior in BALB/c mice only. In BALB/c mice, piracetam, phenotropil, noopept, and semax also reduced anxiety, while phenotropil additionally increased locomotor activity. Thus, the nootropic drugs displayed clear positive modulation of spontaneous orientation in the mice strain with initially low exploratory efficiency (BALB/c) in the cross-maze test. Some drugs (pantogam, nooglutil) exhibited only nootropic properties, while the other drugs exhibited both nootropic effects on the exploratory activity and produced modulation of the anxiety level (piracetam, fenotropil, noopept, semax) and locomotor activity (fenotropil).

  3. Effects of 14-methoxymetopon, a potent opioid agonist, on the responses to the tail electric stimulation test and plus-maze activity in male rats: neuroendocrine correlates.

    Science.gov (United States)

    Urigüen, Leyre; Fernández, Beatriz; Romero, Eva Maria; De Pedro, Nuria; Delgado, Maria Jesús; Guaza, Carmen; Schmidhammer, Helmut; Viveros, Maria Paz

    2002-03-15

    We have studied the effects of 14-methoxymetopon (HS 198), a potent opioid agonist, on the responses to the tail electric stimulation test and plus-maze activity of adult male rats. The prototype mu agonist morphine was used as the drug of reference. Besides we addressed the effects of HS 198 on the serum corticosterone levels and on serotonergic systems of discrete brain regions. Both drugs were administered subcutaneously. Morphine (5 mg/kg) and HS 198 (30 microg/kg) induced a similar effect on the nociceptive test, with both drugs significantly increasing the threshold for the vocalization afterdischarge, which is related to the emotional component of pain. In the plus-maze, morphine (5 mg/kg) and HS 198 (20 and 30 microg/kg) induced similar increases in the percentages of entries and time in the open arms, two parameters related to the anxiety state of the animals. The results indicate that HS 198 is far more potent than morphine in reducing the emotive/affective component of pain and in inducing an anxiolytic effect. HS 198 (30 microg/kg) also induced parallel increases in the serum corticosterone levels and the hypothalamic serotonin content. A possible correlation between the anxiolytic action of the drug and its effect on the hypothalamic serotonergic system is suggested.

  4. Temporary inhibition of dorsal or ventral hippocampus by muscimol: distinct effects on measures of innate anxiety on the elevated plus maze, but similar disruption of contextual fear conditioning.

    Science.gov (United States)

    Zhang, Wei-Ning; Bast, Tobias; Xu, Yan; Feldon, Joram

    2014-04-01

    Studies in rats, involving hippocampal lesions and hippocampal drug infusions, have implicated the hippocampus in the modulation of anxiety-related behaviors and conditioned fear. The ventral hippocampus is considered to be more important for anxiety- and fear-related behaviors than the dorsal hippocampus. In the present study, we compared the role of dorsal and ventral hippocampus in innate anxiety and classical fear conditioning in Wistar rats, examining the effects of temporary pharmacological inhibition by the GABA-A agonist muscimol (0.5 ug/0.5 ul/side) in the elevated plus maze and on fear conditioning to a tone and the conditioning context. In the elevated plus maze, dorsal and ventral hippocampal muscimol caused distinct behavioral changes. The effects of ventral hippocampal muscimol were consistent with suppression of locomotion, possibly accompanied by anxiolytic effects, whereas the pattern of changes caused by dorsal hippocampal muscimol was consistent with anxiogenic effects. In contrast, dorsal and ventral hippocampal muscimol caused similar effects in the fear conditioning experiments, disrupting contextual, but not tone, fear conditioning.

  5. The panicolytic-like effect of fluoxetine in the elevated T-maze is mediated by serotonin-induced activation of endogenous opioids in the dorsal periaqueductal grey.

    Science.gov (United States)

    Roncon, Camila M; Biesdorf, Carla; Santana, Rosangela G; Zangrossi, Hélio; Graeff, Frederico G; Audi, Elisabeth A

    2012-04-01

    Serotonin (5-HT), opioids and the dorsal periaqueductal grey (DPAG) have been implicated in the pathophysiology of panic disorder. In order to study 5-HT-opioid interaction, the opioid antagonist naloxone was injected either systemically (1 mg/kg, i.p.) or intra-DPAG (0.2 μg/0.5 μL) to assess its interference with the effect of chronic fluoxetine (10 mg/kg, i.p., daily for 21 days) or of intra-DPAG 5-HT (8 μg/0.5 μL). Drug effects were measured in the one-escape task of the rat elevated T-maze, an animal model of panic. Pretreatment with systemic naloxone antagonized the lengthening of escape latency caused by chronic fluoxetine, considered a panicolytic-like effect that parallels the drug's therapeutic response in the clinics. Pretreatment with naloxone injected intra-DPAG antagonized both the panicolytic effect of chronic fluoxetine as well as that of 5-HT injected intra-DPAG. Neither the performance of the inhibitory avoidance task in the elevated T-maze, a model of generalized anxiety nor locomotion measured in a circular arena was affected by the above drug treatments. These results indicate that the panicolytic effect of fluoxetine is mediated by endogenous opioids that are activated by 5-HT in the DPAG. They also allow reconciliation between the serotonergic and opioidergic hypotheses of panic disorder pathophysiology.

  6. Temporal patterns of rat behaviour in the central platform of the elevated plus maze. Comparative analysis between male subjects of strains with different basal levels of emotionality.

    Science.gov (United States)

    Casarrubea, M; Faulisi, F; Caternicchia, F; Santangelo, A; Di Giovanni, G; Benigno, A; Magnusson, M S; Crescimanno, G

    2016-08-01

    We have analyzed the temporal patterns of behaviour of male rats of the Wistar and DA/Han strains on the central platform of the elevated plus maze. The ethogram encompassed 10 behavioural elements. Durations, frequencies and latencies showed quantitative differences as to walking and sniffing activities. Wistar rats displayed significantly lower latency and significantly higher durations and frequencies of walking activities. DA/Han rats showed a significant increase of sniffing duration. In addition, DA/Han rats showed a significantly higher amount of time spent in the central platform. Multivariate T-pattern analysis revealed differences in the temporal organization of behaviour of the two rat strains. DA/Han rats showed (a) higher behavioural complexity and variability and (b) a significantly higher mean number of T-patterns than Wistar rats. Taken together, T-pattern analysis of behaviour in the centre of the elevated plus maze can noticeably improve the detection of subtle features of anxiety related behaviour. We suggest that T-pattern analysis could be used as sensitive tool to test the action of anxiolytic and anxiogenic manipulations.

  7. Type 1 diabetes, cognition and the neurologist: Exploring Go/No-Go and Maze tasks in the search for a practical screening tool.

    Science.gov (United States)

    Shinosaki, Jullyanna S M; Rossini, Joaquim C; Jorge, Maria Luiza P M; Macedo, Lorena B C; Tannús, Paulo J

    2017-08-01

    The objectives were to use inexpensive and easy-to-apply tasks in order to investigate the differences between type 1 diabetes mellitus (T1DM) patients and controls regarding attention and impulsivity, which are the basis for key-executive function components that are traditionally assessed using subjective, long and difficult to reproduce questionnaires. Additionally, we sought to correlate these differences with clinical characteristics, and to explore correlations between the tasks. We compared the scores of 20 T1DM patients with 20 controls. The sample population included both males and females, aged 12-15 years. They were tested using a Go/No-Go paradigm and a Maze task, and correlations were verified between the groups. The T1DM group had more anticipatory answers (AA) in the Go/No-Go task (p 9% correlated with a greater number of alleys in Mazes (p<0.05). The tasks' parameters were coherent among each test, and also between them. We found indicators of inattention and impulsivity to be associated with T1DM, with inattention being closely related with hyperglycemia, and impulsivity being associated with hypoglycemia. Further research is needed to study diabetes-associated cognitive decline with more objective parameters, and to analyse the reliability and psychometric properties of the tasks proposed in this study. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.

  8. Effects of 5-HT1A receptor agonists and NMDA receptor antagonists in the social interaction test and the elevated plus maze.

    Science.gov (United States)

    Dunn, R W; Corbett, R; Fielding, S

    1989-10-01

    The effects of several 5-HT1A agonists and excitatory amino acid antagonists were compared to the standard benzodiazepines, diazepam and chlordiazepoxide (CDP) in two assays predictive of anxiolytic activity, the social interaction and elevated plus maze procedures. Indicative of anxiolytic effects the 5-HT1A agonists, buspirone, gepirone and 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) all significantly increased social interaction time and open arm exploration time in the social interaction and elevated plus maze procedures, respectively. Likewise, anxiolytic activity in these assays were also produced by the competitive N-methyl-D-aspartate (NMDA) antagonists, 2-amino-5-phosphonovaleric acid (AP-5), 2-amino-7-phosphonoheptanoic acid (AP-7), 3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP) and the non-competitive NMDA antagonist, (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine (MK-801) while NMDA produced anxiogenic effects. Furthermore, the anxiolytic effects of these agents were of equal magnitude to the benzodiazepines. These two classes of compounds were differentiated in the yohimbine-induced seizure assay, with the NMDA antagonists dose dependently antagonizing seizures similar to the benzodiazepines while the 5-HT1A agonists were inactive. These results suggest that the 5-HT1A agonists and the NMDA antagonists may be potential non-classical anxiolytic agents with different mechanisms of action.

  9. Anxiolytic-like effect of (S)-WAY 100135, a 5-HT1A receptor antagonist, in the murine elevated plus-maze test.

    Science.gov (United States)

    Rodgers, R J; Cole, J C

    1994-08-22

    The effects of (S)-WAY 100135 ((S)-N-tert-butyl-3-(4-(2-methoxyphenyl)- piperazin-1-yl)-2-phenyl-propanamide dihydrochloride; 2.5-20.0 mg/kg), a 5-HT1A receptor antagonist, on the behaviour of male mice were examined in the elevated plus-maze test of anxiety. An ethological scoring technique was used to provide a comprehensive profile of drug action. Only minor changes in behaviour were observed at 2.5 and 5.0 mg/kg, and consisted of reductions in some (though not all) risk assessment measures. At 10 mg/kg, the compound increased percent open arm entries and percent open arm time, without altering general activity levels. This classic anxiolytic-like profile was confirmed by major reductions in risk assessment measures including protected head-dips and protected stretched attend postures. Although many of the same changes were also observed at 20 mg/kg, the absence of an effect on percent open arm time and a tendency towards increased non-exploratory behaviour suggested (1) some loss of anxiolytic activity and (2) a possible contribution of non-specific factors at higher doses. Present findings indicate that (S)-WAY 100135 produces clear anxiolytic-like effects in the murine elevated plus-maze, a profile that can be distinguished from that produced by 5-HT1A receptor partial agonists in the same test.

  10. Spatial learning in men undergoing alcohol detoxification.

    Science.gov (United States)

    Ceccanti, Mauro; Hamilton, Derek; Coriale, Giovanna; Carito, Valentina; Aloe, Luigi; Chaldakov, George; Romeo, Marina; Ceccanti, Marco; Iannitelli, Angela; Fiore, Marco

    2015-10-01

    Alcohol dependence is a major public health problem worldwide. Brain and behavioral disruptions including changes in cognitive abilities are common features of alcohol addiction. Thus, the present study was aimed to investigate spatial learning and memory in 29 alcoholic men undergoing alcohol detoxification by using a virtual Morris maze task. As age-matched controls we recruited 29 men among occasional drinkers without history of alcohol dependence and/or alcohol related diseases and with a negative blood alcohol level at the time of testing. We found that the responses to the virtual Morris maze are impaired in men undergoing alcohol detoxification. Notably they showed increased latencies in the first movement during the trials, increased latencies in retrieving the hidden platform and increased latencies in reaching the visible platform. These findings were associated with reduced swimming time in the target quadrant of the pool where the platform had been during the 4 hidden platform trials of the learning phase compared to controls. Such increasing latency responses may suggest motor control, attentional and motivational deficits due to alcohol detoxification.

  11. Sex and Rearing Condition Modify the Effects of Perinatal Lead Exposure on Learning and Memory

    OpenAIRE

    Anderson, D.W.; Pothakos, K.; Schneider, J.S.

    2012-01-01

    Developmental lead (Pb) exposure is associated with cognitive impairments in humans and rodents alike. In particular, impaired spatial learning and memory, as assessed using the Morris water maze (MWM), has been noted in developmentally Pb –exposed rats. Although sex and rearing environment can influence MWM performance in normal animals, the interactions of sex and rearing environment on the impact of developmental Pb exposure on hippocampal-dependent processes has not been well characterize...

  12. Antidepressant suppression of non-REM sleep spindles and REM sleep impairs hippocampus-dependent learning while augmenting striatum-dependent learning.

    Science.gov (United States)

    Watts, Alain; Gritton, Howard J; Sweigart, Jamie; Poe, Gina R

    2012-09-26

    Rapid eye movement (REM) sleep enhances hippocampus-dependent associative memory, but REM deprivation has little impact on striatum-dependent procedural learning. Antidepressant medications are known to inhibit REM sleep, but it is not well understood if antidepressant treatments impact learning and memory. We explored antidepressant REM suppression effects on learning by training animals daily on a spatial task under familiar and novel conditions, followed by training on a procedural memory task. Daily treatment with the antidepressant and norepinephrine reuptake inhibitor desipramine (DMI) strongly suppressed REM sleep in rats for several hours, as has been described in humans. We also found that DMI treatment reduced the spindle-rich transition-to-REM sleep state (TR), which has not been previously reported. DMI REM suppression gradually weakened performance on a once familiar hippocampus-dependent maze (reconsolidation error). DMI also impaired learning of the novel maze (consolidation error). Unexpectedly, learning of novel reward positions and memory of familiar positions were equally and oppositely correlated with amounts of TR sleep. Conversely, DMI treatment enhanced performance on a separate striatum-dependent, procedural T-maze task that was positively correlated with the amounts of slow-wave sleep (SWS). Our results suggest that learning strategy switches in patients taking REM sleep-suppressing antidepressants might serve to offset sleep-dependent hippocampal impairments to partially preserve performance. State-performance correlations support a model wherein reconsolidation of hippocampus-dependent familiar memories occurs during REM sleep, novel information is incorporated and consolidated during TR, and dorsal striatum-dependent procedural learning is augmented during SWS.

  13. Mice in an enriched environment learn more flexibly because of adult hippocampal neurogenesis.

    Science.gov (United States)

    Garthe, Alexander; Roeder, Ingo; Kempermann, Gerd

    2016-02-01

    We here show that living in a stimulus-rich environment (ENR) improves water maze learning with respect to specific key indicators that in previous loss-of-function experiments have been shown to rely on adult hippocampal neurogenesis. Analyzing the strategies employed by mice to locate the hidden platform in the water maze revealed that ENR facilitated task acquisition by increasing the probability to use effective search strategies. ENR also enhanced the animals' behavioral flexibility, when the escape platform was moved to a new location. Treatment with temozolomide, which is known to reduce adult neurogenesis, abolished the effects of ENR on both acquisition and flexibility, while leaving other aspects of water maze learning untouched. These characteristic effects and interdependencies were not seen in parallel experiments with voluntary wheel running (RUN), a second pro-neurogenic behavioral stimulus. Since the histological assessment of adult neurogenesis is by necessity an end-point measure, the levels of neurogenesis over the course of the experiment can only be inferred and the present study focused on behavioral parameters as analytical endpoints. Although the correlation of physical activity with precursor cell proliferation and of learning and the survival of new neurons is well established, how the specific functional effects described here relate to dynamic changes in the stem cell niche remains to be addressed. Nevertheless, our findings support the hypothesis that adult neurogenesis is a critical mechanism underlying the beneficial effects of leading an active live, rich in experiences.

  14. Comparison of learning and memory of Apis cerana and Apis mellifera.

    Science.gov (United States)

    Qin, Qiu-Hong; He, Xu-Jiang; Tian, Liu-Qing; Zhang, Shao-Wu; Zeng, Zhi-Jiang

    2012-10-01

    The honeybee is an excellent model organism for research on learning and memory among invertebrates. Learning and memory in honeybees has intrigued neuroscientists and entomologists in the last few decades, but attention has focused almost solely on the Western honeybee, Apis mellifera. In contrast, there have been few studies on learning and memory in the Eastern honeybee, Apis cerana. Here we report comparative behavioral data of color and grating learning and memory for A. cerana and A. mellifera in China, gathered using a Y-maze apparatus. We show for the first time that the learning and memory performance of A. cerana is significantly better on both color and grating patterns than that of A. mellifera. This study provides the first evidence of a learning and memory difference between A. cerana and A. mellifera under controlled conditions, and it is an important basis for the further study of the mechanism of learning and memory in honeybees.

  15. Effect of Royal Jelly on Improving Passive Avoidance Learning and Spatial Learning and Memory in Rats

    Directory of Open Access Journals (Sweden)

    H Alaei

    2012-06-01

    Full Text Available Introduction: Studies have proposed that royal jelly(RJ has various biological activities in different cells and tissues. Since it has been demonstrated that RJ contains compounds having desirable effects on central neurons system and neural functions, the present study aimed to investigate the effect of royal jelly on learning and memory in rats. Methods: Male wistar rats were divided into two groups, the royal jelly and the control. In the RJ group, the rats received a food that contained 3% RJ instead of regular food for 10 days. Then learning and memory were investigated in these animals through both passive avoidance learning test(1 day and 1 week after receiving electrical shock and Morris water maze test(1 day and 1 week after a 4-day learning period. Results: The study results indicated that the food containing RJ in the RJ group significantly increased the time of the first entrance to the dark room one week after the electrical shock in passive avoidance learning test. In other words, the findings suggest an improvement of learning and memory in RJ group. In the acquisition phase of Morris water maze test, rats receiving RJ found the underwater escape plate during less time and distance comparing with the control group. Furthermore, one week after the acquisition phase, in the retention phase, rats spent more time in the quadrant in which the escape plate was previously located. Conclusion: The present study findings propose that Royal Jelly can improve cognitive processes through positive effects on neural functions and probably has a significant influence on prevention and therapy of some neuronal disorders.

  16. Spatial learning and psychomotor performance of C57BL/6 mice: age sensitivity and reliability of individual differences.

    Science.gov (United States)

    de Fiebre, Nancyellen C; Sumien, Nathalie; Forster, Michael J; de Fiebre, Christopher M

    2006-09-01

    Two tests often used in aging research, the elevated path test and the Morris water maze test, were examined for their application to the study of brain aging in a large sample of C57BL/6JNia mice. Specifically, these studies assessed: (1) sensitivity to age and the degree of interrelatedness among different behavioral measures derived from these tests, (2) the effect of age on variation in the measurements, and (3) the reliability of individual differences in performance on the tests. Both tests detected age-related deficits in group performance that occurred independently of each other. However, analysis of data obtained on the Morris water maze test revealed three relatively independent components of cognitive performance. Performance in initial acquisition of spatial learning in the Morris maze was not highly correlated with performance during reversal learning (when mice were required to learn a new spatial location), whereas performance in both of those phases was independent of spatial performance assessed during a single probe trial administered at the end of acquisition training. Moreover, impaired performance during initial acquisition could be detected at an earlier age than impairments in reversal learning. There were modest but significant age-related increases in the variance of both elevated path test scores and in several measures of learning in the Morris maze test. Analysis of test scores of mice across repeated testing sessions confirmed reliability of the measurements obtained for cognitive and psychomotor function. Power calculations confirmed that there are sufficiently large age-related differences in elevated path test performance, relative to within age variability, to render this test useful for studies into the ability of an intervention to prevent or reverse age-related deficits in psychomotor performance. Power calculations indicated a need for larger sample sizes for detection of intervention effects on cognitive components of the

  17. Anxiolytic-like effects observed in rats exposed to the elevated zero-maze following treatment with 5-HT2/5-HT3/5-HT4 ligands

    OpenAIRE

    Rob Bell; Aaron A. Duke; Gilmore, Paula E.; Deaglan Page; Laurent Bègue

    2014-01-01

    The present study examined the effects of administering selective 5-HT antagonists and agonists to rats tested in the elevated zero-maze (EZM) model of anxiety. The EZM paradigm has advantages over the elevated plus-maze (EPM) paradigm with respect to measuring anxiety, yet has been utilized less frequently. Three experiments were conducted each with a diazepam control (0.25, 0.5 and 0.75 mg/kg). In the first experiment, we administered the 5-HT2C antagonist RS 102221 (0.5, 1.0, and 2.0 mg/kg...

  18. Recuperación de la contracción auricular luego de la cirugía de MAZE III izquierdo

    Directory of Open Access Journals (Sweden)

    Antonio Piazza

    2009-01-01

    Full Text Available IntroducciónLa cirugía de MAZE III izquierdo demostró una efectividad elevada en la restauración a ritmo sinusal. Sin embargo, la efectividad en la restauración de la sístole auricular en poblaciones con cardiopatía estructural y el predominio de enfermedad reumática resultan áreas de incertidumbre.ObjetivoEvaluar la efectividad de la cirugía de MAZE en la restauración de la sístole auricular en pacientes con cardiopatía estructural.Material y métodosEstudio prospectivo, consecutivo de 27 pacientes portadores de fibrilación auricular crónica persistente con indicación de cirugía cardiovascular y en los que se realizó la técnica de MAZE como tratamiento de la arritmia. La presencia de sístole auricular se evaluó mediante Doppler tisular del anillo mitral lateral.ResultadosEn una población caracterizada por predominancia de cardiopatía reumática (41% y tiempo prolongado de evolución de la arritmia (61 meses promedio, al final del seguimiento el 87% se encontraba en ritmo sinusal en el 80% de los casos con actividad mecánica. El antecedente de cardiopatía reumática, una duración de la arritmia mayor de 5,5 años, el sexo femenino y el reemplazo de válvula mitral fueron variables estadísticamente significativas en cuanto a la ausencia de sístole auricular. No tuvieron significación la edad, la fracción de eyección del ventrículo izquierdo y el tamaño de la aurícula izquierda.ConclusionesEn esta población es significativa la falta de correspondencia entre ritmo sinusal y sístole auricular. El Doppler tisular es un método útil para identificar a aquellos pacientes sin contracción auricular. El impacto clínico de este hallazgo está vinculado con la decisión en la continuidad del tratamiento anticoagulante.REV ARGENT CARDIOL 2009;77:7-13.

  19. Modified Maze lines plus pulmonary vein isolation created by radiofrequency catheter ablation on the atrial wall to treat atrial fibrillation in elderly

    Institute of Scientific and Technical Information of China (English)

    Caiyi LU; Shiwen WANG; Xinping DU; Yinglong HOU; Qiao XUE; Xinli WU; Rui CHEN; Peng LIU

    2005-01-01

    Objective To evaluate the effect of modified Maze lines plus pulmonary vein (PV) isolation created by radiofrequency catheter ablation (RFCA) on atrial wall guided by a novel geometry mapping system in the treatment of elderly patients with paroxysmal atrial fibrillation (PAF). Methods After regular electrophysiological study, transseptal punctures were achieved twice with Swartz L1 and R1 sheaths. PV angiographies were conducted to evaluate their orifices and branches. A balloon electrode array catheter with 64 electrodes was put in the middle of the left atrium. Atrium geometry was constructed using Ensite 3000 Navx system. Two RFCA lesion loops and three lines (modified Maze) were created on left and right atrial walls. Each lesion point was ablated for 30 seconds with preset temperature 50 (ae) and energy 30W. The disappearance or 80% decrease of the amplitude of target atrial potential and 10 to 20(|), decrease of ablation impedance were used as an index of effective ablation. Results A total of 11 patients (7 male and 4 female, mean age, 68.7±5.1 years) were enrolled. PAF history was 7.9±4.5 years. PAF could not be prevented by mean 3.1±1.6 antiarrhythmic agents in 6.3±3.4 years. None of the patients had complications with structural heart disease or stroke. Left atrial diameter was 41.3±3.6 mm and LVEF was 59.2±3.7% on echocardiography. Two loops and three lines were completed with 67.8±13.1 (73-167) lesion points. Altogether 76-168 (89.4±15.3) lesion points were created in each patient. PAF could not be provoked by rapid burst pacing up to 600 beat per minute delivered from paroxysmal coronary sinus electrode pair.Complete PV electrical isolation was confirmed by three-dimensional activation mapping. Mean procedure time was 2.7±0.6 hours and fluoroscopy time was 17.8±9.4 minutes. Patients were discharged with oral aspirin and without antiarrhythmic agents. During follow up of 6.5±1.8 months, seven patients were PAF symptom free (63.6%). PAF

  20. 5-HT1A and benzodiazepine receptors in the basolateral amygdala modulate anxiety in the social interaction test, but not in the elevated plus-maze.

    Science.gov (United States)

    Gonzalez, L E; Andrews, N; File, S E

    1996-09-01

    In order to investigate the role of the 5-HT1A receptors of the amygdala in modulating anxiety, rats were implanted with bilateral cannulae aimed at the basolateral nucleus of the amygdala complex and infused with either artificial cerebrospinal fluid (aCSF) or the selective 5-HT1A receptor agonist 8-OH-DPAT (50-200 ng) and tested in two animal models of anxiety. In the elevated plus-maze test, no significant effects were detected in this dose range. In contrast, 8-OH-DPAT caused an overall reduction in levels of social investigation, thus indicating anxiogenic actions in the social interaction test. At 50 ng, 8-OH-DPAT had a selective action on anxiety, while at 200 ng there was a concomitant reduction in locomotor activity and, in some animals, signs of the 5-HT1A syndrome. Evidence that the anxiogenic effect of 8-OH-DPAT (50 ng) was due to activation of 5-HT1A receptors came from the finding that (-)-tertatolol, a 5-HT1A receptor antagonist, reversed this effect at a dose (1.5 micrograms) which was silent when given alone. The benzodiazepine receptor agonist, midazolam (1 and 2 micrograms) was bilaterally administered into the basolateral nucleus of the amygdala and evoked clear-cut anxiolytic effects in the social interaction test. These data indicate that the agonist activation of post-synaptic 5-HT1A receptors in the basolateral nucleus of the amygdala may produce anxiogenic effects, while agonist activation of BDZ receptors in the same areas evokes anxiolytic effects. Our results from the social interaction test are similar to those previously reported from tests of anxiety using punished paradigms, but contrast with those found in the elevated plus-maze. Thus, it is concluded that either the two tests have different sensitivities to midazolam and 8-OH-DPAT or more intriguingly, the tests are evoking fundamentally different states of anxiety, with that evoked by the plus-maze being mediated via brain areas or receptors different from those studied here.

  1. Associative learning performance is impaired in zebrafish (Danio rerio) by the NMDA-R antagonist MK-801.

    Science.gov (United States)

    Sison, Margarette; Gerlai, Robert

    2011-09-01

    The zebrafish is gaining popularity in behavioral neuroscience perhaps because of a promise of efficient large scale mutagenesis and drug screens that could identify a substantial number of yet undiscovered molecular players involved in complex traits. Learning and memory are complex functions of the brain and the analysis of their mechanisms may benefit from such large scale zebrafish screens. One bottleneck in this research is the paucity of appropriate behavioral screening paradigms, which may be due to the relatively uncharacterized nature of the behavior of this species. Here we show that zebrafish exhibit good learning performance in a task adapted from the mammalian literature, a plus maze in which zebrafish are required to associate a neutral visual stimulus with the presence of conspecifics, the rewarding unconditioned stimulus. Furthermore, we show that MK-801, a non-competitive NMDA-R antagonist, impairs memory performance in this maze when administered right after training or just before recall but not when given before training at a dose that does not impair motor function, perception or motivation. These results suggest that the plus maze associative learning paradigm has face and construct validity and that zebrafish may become an appropriate and translationally relevant study species for the analysis of the mechanisms of vertebrate, including mammalian, learning and memory.

  2. Morphine Reward Promotes Cue-Sensitive Learning: Implication of Dorsal Striatal CREB Activity

    Directory of Open Access Journals (Sweden)

    Mathieu Baudonnat

    2017-05-01

    Full Text Available Different parallel neural circuits interact and may even compete to process and store information: whereas stimulus–response (S–R learning critically depends on the dorsal striatum (DS, spatial memory relies on the hippocampus (HPC. Strikingly, despite its potential importance for our understanding of addictive behaviors, the impact of drug rewards on memory systems dynamics has not been extensively studied. Here, we assessed long-term effects of drug- vs food reinforcement on the subsequent use of S–R vs spatial learning strategies and their neural substrates. Mice were trained in a Y-maze cue-guided task, during which either food or morphine injections into the ventral tegmental area (VTA were used as rewards. Although drug- and food-reinforced mice learned the Y-maze task equally well, drug-reinforced mice exhibited a preferential use of an S–R learning strategy when tested in a water-maze competition task designed to dissociate cue-based and spatial learning. This cognitive bias was associated with a persistent increase in the phosphorylated form of cAMP response element-binding protein phosphorylation (pCREB within the DS, and a decrease of pCREB expression in the HPC. Pharmacological inhibition of striatal PKA pathway in drug-rewarded mice limited the morphine-induced increase in levels of pCREB in DS and restored a balanced use of spatial vs cue-based learning. Our findings suggest that drug (opiate reward biases the engagement of separate memory systems toward a predominant use of the cue-dependent system via an increase in learning-related striatal pCREB activity. Persistent functional imbalance between striatal and hippocampal activity could contribute to the persistence of addictive behaviors, or counteract the efficiency of pharmacological or psychotherapeutic treatments.

  3. Learning How To Learn.

    Science.gov (United States)

    Barnett, Demian

    2000-01-01

    In one California high school, learning to learn is a measurable outcome assessed by all students' participation in graduation by exhibition. Students must meet state requirements and demonstrate learning prowess by publicly exhibiting their skills in math, science, language arts, social science, service learning, and postgraduation planning. (MLH)

  4. Learning How To Learn.

    Science.gov (United States)

    Barnett, Demian

    2000-01-01

    In one California high school, learning to learn is a measurable outcome assessed by all students' participation in graduation by exhibition. Students must meet state requirements and demonstrate learning prowess by publicly exhibiting their skills in math, science, language arts, social science, service learning, and postgraduation planning. (MLH)

  5. Tau reduction diminishes spatial learning and memory deficits after mild repetitive traumatic brain injury in mice.

    Directory of Open Access Journals (Sweden)

    Jason S Cheng

    Full Text Available OBJECTIVE: Because reduction of the microtubule-associated protein Tau has beneficial effects in mouse models of Alzheimer's disease and epilepsy, we wanted to determine whether this strategy can also improve the outcome of mild traumatic brain injury (TBI. METHODS: We adapted a mild frontal impact model of TBI for wildtype C57Bl/6J mice and characterized the behavioral deficits it causes in these animals. The Barnes maze, Y maze, contextual and cued fear conditioning, elevated plus maze, open field, balance beam, and forced swim test were used to assess different behavioral functions. Magnetic resonance imaging (MRI, 7 Tesla and histological analysis of brain sections were used to look for neuropathological alterations. We also compared the functional effects of this TBI model and of controlled cortical impact in mice with two, one or no Tau alleles. RESULTS: Repeated (2-hit, but not single (1-hit, mild frontal impact impaired spatial learning and memory in wildtype mice as determined by testing of mice in the Barnes maze one month after the injury. Locomotor activity, anxiety, depression and fear related behaviors did not differ between injured and sham-injured mice. MRI imaging did not reveal focal injury or mass lesions shortly after the injury. Complete ablation or partial reduction of tau prevented deficits in spatial learning and memory after repeated mild frontal impact. Complete tau ablation also showed a trend towards protection after a single controlled cortical impact. Complete or partial reduction of tau also reduced the level of axonopathy in the corpus callosum after repeated mild frontal impact. INTERPRETATION: Tau promotes or enables the development of learning and memory deficits and of axonopathy after mild TBI, and tau reduction counteracts these adverse effects.

  6. Preserved learning and memory following 5-fluorouracil and cyclophosphamide treatment in rats.

    Science.gov (United States)

    Long, Jeffrey M; Lee, Garrick D; Kelley-Bell, Bennett; Spangler, Edward L; Perez, Evelyn J; Longo, Dan L; de Cabo, Rafael; Zou, Sige; Rapp, Peter R

    2011-11-01

    Some patients experience enduring cognitive impairment after cancer treatment, a condition termed "chemofog". Animal models allow assessment of chemotherapy effects on learning and memory per se, independent of changes due to cancer itself or associated health consequences such as depression. The present study examined the long-term learning and memory effects of a chemotherapy cocktail used widely in the treatment of breast cancer, consisting of 5-fluorouracil (5FU) and cyclophosphamide (CYP). Eighty 5-month old male F344 rats received contextual and cued fear conditioning before treatment with saline, or a low or high dose drug cocktail (50mg/kg CYP and 75 mg/kg 5FU, or 75 mg/kg CYP and 120 mg/kg 5FU, i.p., respectively) every 30 days for 2 months. After a 2-month, no-drug recovery, both long-term retention and new task acquisition in the water maze and 14-unit T-maze were assessed. Neither dose of the CYP/5FU cocktail impaired retrograde fear memory despite marked toxicity documented by enduring weight loss and 50% mortality at the higher dose. Acquisition in the water maze and Stone maze was also normal relative to controls in rats treated with CYP/5FU. The results contribute to a growing literature suggesting that learning and memory mediated by the hippocampus can be relatively resistant to chemotherapy. Future investigation may need to focus on assessments of processing speed, executive function and attention, and the possible interactive contribution of cancer itself and aging to the post-treatment development of cognitive impairment. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Learning How to Learn

    DEFF Research Database (Denmark)

    Lauridsen, Karen M.; Lauridsen, Ole

    Ole Lauridsen, Aarhus School of Business and Social Sciences, Aarhus University, Denmark Karen M. Lauridsen, Aarhus School of Business and Social Sciences, Aarhus University, Denmark Learning Styles in Higher Education – Learning How to Learn Applying learning styles (LS) in higher education...... presented in a way that suits their individual LS preferences. In this presentation you will see how we as teachers can assist students in applying LS strategies that cater to their individual learning strengths. This will be based on general recommendations for HE teaching and learning supported...... by Constructivist learning theory and current basic knowledge of how the brain learns. The LS concept will thus be placed in a broader learning theoretical context as a strong learning and teaching tool. Participants will be offered the opportunity to have their own LS preferences established before...

  8. Anxiogenic-like effects of Uncaria tomentosa (Willd.) DC. aqueous extract in an elevated plus maze test in mice: a preliminary study.

    Science.gov (United States)

    Bigliani, María Celeste; Rosso, María Celeste; Zunino, Paula M; Baiardi, Gustavo; Ponce, Andrés Alberto

    2013-01-01

    The purpose of this study was to examine the effect of orally administered Uncaria tomentosa aqueous extracts (UTE) (Willd. ex Roem. & Schult.) DC. (Rubiaceae) during 7, 15, 30 and 90 days of treatment on the expression of anxiety, as expressed in the elevated plus maze test in male Albino Swiss mice. UTE revealed an anxiogenic effect in relation to the control group at 15 and 30 days, but it was reversed after 90 days of administration, without affecting the locomotor activity or any deleterious effects on the overall performance of the animal, either for its ambulation, or clinical status, and body weight and organ weight/body weight from liver, lung and kidney were unaffected. These biphasic effects are usually indicative of heterogeneity in sites of action due to the presence of many alkaloids (speciophylline, uncarine F and uncarine E) and flavanols (catechin and epigallocatechin) identified and isolated from UTE.

  9. Effect of experience with pine (Pituophis melanoleucus) and king (Lampropeltis getulus) snake odors on Y-maze behavior of pine snake hatchlings.

    Science.gov (United States)

    Burger, J; Boarman, W; Kurzava, L; Gochfeld, M

    1991-01-01

    The abilities of hatchling pine snakes (Pituophis melanoleucus) and king snakes (Lampropeltis getulus) to discriminate the chemical trails of pine and king snakes was investigated inY-maze experiments. Pine snakes were housed for 17 days either with shavings impregnated with pine snake odor, king snake odor, or no odor to test for the effect of experience on choice. Both pine and king snake hatchlings entered the arm with the pine snake odor and did not enter the arm with the king snake odor. The data support the hypothesis that hatchlings of both species can distinguish conspecific odors from other odors and that our manipulation of previous experience was without effect for pine snake hatchlings.

  10. Within-subject decline in delayed-non-match-to-sample radial arm maze performance in aging Sprague-Dawley rats.

    Science.gov (United States)

    Chrobak, J J; Hanin, I; Lorens, S A; Napier, T C

    1995-04-01

    A within-subject design was used to examine delayed-non-match-to-sample radial arm maze performance in aging (6-18 months) male Sprague-Dawley rats. A decrease in correct choices and an increase in retroactive errors were observed at all retention intervals at 18 months of age compared with performance at 6 or 12 months. No age by retention interval interaction was observed. Neither age nor increasing retention interval influenced proactive errors during the retention test. The observation of an age- and delay-dependent increase in retroactive errors, but not proactive errors, suggests that the deficit relates to a memory dysfunction as opposed to a generalized performance deficit.

  11. Acute and chronic anxiogenic-like response to fluoxetine in rats in the elevated plus-maze: modulation by stressful handling.

    Science.gov (United States)

    Robert, Gabriel; Drapier, Dominique; Bentué-Ferrer, Danièle; Renault, Alain; Reymann, Jean-Michel

    2011-07-07

    While antidepressants are widely prescribed to humans for the treatment of anxiety, the results achieved with animal anxiety models are conflicting. The experimental procedure and the prior test history of the animals are critical parameters that are largely susceptible to influence the results and their interpretation. We compared the effect of 5mg fluoxetine administered to six groups of rats subjected to the psychopharmacological test of the elevated plus-maze, under experimental conditions designed to demonstrate the effect of handling and one daily injection on the response to fluoxetine. The results show that for animals with the same recent experience, fluoxetine, when administered once or over a period of 15 days, induces anxiogenic-like behaviour. On the other hand, our results also show that stressful handling has an anxiolytic-like effect modulating the anxiogenic-like effect of fluoxetine, without eliminating it altogether. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Estimation of the level of anxiety in rats: differences in results of open-field test, elevated plus-maze test, and Vogel's conflict test.

    Science.gov (United States)

    Sudakov, S K; Nazarova, G A; Alekseeva, E V; Bashkatova, V G

    2013-07-01

    We compared individual anxiety assessed by three standard tests, open-field test, elevated plus-maze test, and Vogel conflict drinking test, in the same animals. No significant correlations between the main anxiety parameters were found in these three experimental models. Groups of animals with high and low anxiety rats were formed by a single parameter and subsequent selection of two extreme groups (10%). It was found that none of the tests could be used for reliable estimation of individual anxiety in rats. The individual anxiety level with high degree of confidence was determined in high-anxiety and low-anxiety rats demonstrating behavioral parameters above and below the mean values in all tests used. Therefore, several tests should be used for evaluation of the individual anxiety or sensitivity to emotional stress.

  13. Sex-dependent effects of developmental exposure to different pesticides on spatial learning. The role of induced neuroinflammation in the hippocampus.

    Science.gov (United States)

    Gómez-Giménez, Belén; Llansola, Marta; Hernández-Rabaza, Vicente; Cabrera-Pastor, Andrea; Malaguarnera, Michele; Agusti, Ana; Felipo, Vicente

    2017-01-01

    The use of pesticides has been associated with impaired neurodevelopment in children. The aims of this work were to assess: 1) the effects on spatial learning of developmental exposure to pesticides 2) if the effects are sex-dependent and 3) if hippocampal neuroinflammation is associated with the impairment of spatial learning. We analyzed the effects of developmental exposure to four pesticides: chlorpyrifos, carbaryl, endosulfan and cypermethrin. Exposure was from gestational day 7 to post-natal day 21 and spatial learning and memory was assessed when the rats were young adults. The effects of pesticides on spatial learning were pesticide and gender-dependent. Carbaryl did not affect spatial learning in males or females. Endosulfan and chlorpyrifos impaired learning in males but not in females. Cypermethrin improved spatial learning in the Morris water maze both in males and females while impaired learning in the radial maze only in males. Spatial learning ability was lower in control female rats than in males. All pesticides induced neuroinflammation, increasing IL-1b content in the hippocampus and there is a negative correlation between IL-1b levels in the hippocampus and spatial learning. Neuroinflammation would contribute to the effects of pesticides on spatial learning. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Decision time and perseveration of adolescent rats in the T-maze are affected differentially by buspirone and independent of 5-HT-1A expression.

    Science.gov (United States)

    Rhoads, Dennis E; Grimes, Nicole; Kaushal, Sunaina; Mallari, Janine; Orlando, Krystal

    2012-07-01

    Disruption of spontaneous alternation behavior (SAB) by the serotonin 1A (5-HT-1A) receptor agonist, 8-hydroxy-dipropylaminotetraline (8-OH-DPAT), results in repetitive behaviors that have been used to model the perseveration and indecisiveness of human obsessive-compulsive disorder (OCD). In the present study, we compared the effects of buspirone to those of 8-OH-DPAT in two strains of adolescent rats and analyzed repetitive choices of arms of the maze and prolonged apparent decision time due to induction of vicarious trial and error (VTE) behavior. In adolescent Sprague-Dawley (SD) rats, 8-OH-DPAT induced repetitive choices of arms of the maze (perseveration) and increased the apparent decision time. Buspirone induced VTE behavior and increased apparent decision time without perseveration. This distinct effect of buspirone was seen in SD adolescents but not in Long-Evans (LE) adolescents which appeared to be insensitive to buspirone. Lack of responsiveness to buspirone was dependent on the developmental stage because buspirone induced VTE behavior and prolonged decision time in LE adults. Western blotting of brain 5-HT-1A receptors showed expression of receptor protein in adolescent LE brain was comparable to that of adolescent SD and adult LE. The 5-HT-1A antagonist WAY 100365 blocked the effect 8-OH-DPAT on repetitive choice of arms but not the effect of buspirone on VTE behavior. We conclude that the adolescent LE rat has normal levels of 5-HT-1A receptor and that the effect of buspirone on VTE behavior is not mediated by the 5-HT-1A receptor. The LE strain may provide a useful system for further study of the adolescent brain and potential genetic differences in induction of repetitive behaviors.

  15. The effect of D2 agonist versus D2 antagonist on the fear behavior in the male rats using plus-maze method: the prospective study

    Directory of Open Access Journals (Sweden)

    Sabzehkhah S

    2009-11-01

    Full Text Available "nBackground: Dopaminergic is the most important neurotransmitter is fear. The dopaminergic mesolimbic pathway has essential role in excitable behavior, and it's role in Parkinson disease. The aim of this research in study, the effect of dopaminergic pathway in fear response. "n"nMethods: The elevated plus maze was used in combination with the percentage of time spent in the open arms of the maze (OAT% and the percentage of entries into the open arms (OAE% to measure fear. Increases in the OAT% and OAE% indicate an anxiolytic effect (reduction in anxiety, whereas decreases in the OAE% and OAT% indicate an anxiogenic effect. After five days, the rats were injected with saline and different doses of sulpiride and Bromocriptine."n"nResults: Results showed that intracerebroventricular administration of sulpiride, in the doses of 5, 20μg/rat and bromocriptine, D2 agonist in doses 65, 95μg/rat produced a significant effect comparing to sham groups (p<0.05. While intracerebroventricular administration of sulpiride 15, 10μg/rat, and bromocriptine 70, 80μg/rat, did not show any significant effect comparing with sham group (p<0.05. In the current research intracerebroventricular administration of sulpiride, D2 antagonist at the doses of 5, 10, 15, 20μg/rat and Bromocriptine, D2 agonist in the doses of 65, 70, 80, 95μg/rat were used and theire effect on the fear behavior were studied. "n"nConclusions: The possible effect of Dopaminergic system in the fear process, especially D2 receptor increase fear.

  16. Differential induction of c-Jun and Fos-like proteins in rat hippocampus and dorsal striatum after training in two water maze tasks.

    Science.gov (United States)

    Teather, Lisa A; Packard, Mark G; Smith, Diane E; Ellis-Behnke, Rutledge G; Bazan, Nicolas G

    2005-09-01

    Research examining the neuroanatomical bases of memory in mammals suggests that the hippocampus and dorsal striatum are parts of independent memory systems that mediate "cognitive" and stimulus-response "habit" memory, respectively. At the molecular level, increasing evidence indicates a role for immediate early gene (IEG) expression in memory formation. The present experiment examined whether acquisition of cognitive and habit memory result in differential patterns of IEG protein product expression in these two brain structures. Adult male Long-Evans rats were trained in either a hippocampal-dependent spatial water maze task, or a dorsal striatal-dependent cued water maze task. Ninety minutes after task acquisition, brains were removed and processed for immunocytochemical procedures, and the number of cells expressing Fos-like immunoreactivity (Fos-like-IR) and c-Jun-IR in sections from the dorsal hippocampus and the dorsal striatum were counted. In the dorsal hippocampus of rats trained in the spatial task, there were significantly more c-Jun-IR pyramidal cells in the CA1 and CA3 regions, relative to rats that had acquired the cued task, yoked controls (free-swim), or naïve (home cage) rats. Relative to rats receiving cued task training and control conditions, increases in Fos-like IR were also observed in the CA1 region of rats trained in the spatial task. In rats that had acquired the cued task, patches of c-Jun-IR were observed in the posteroventral striatum; no such patches were evident in rats trained in the spatial task, yoked-control rats, or naïve rats. The results demonstrate that IEG protein product expression is up-regulated in a task-dependent and brain structure-specific manner shortly after acquisition of cognitive and habit memory tasks.

  17. A hippocampal nicotinic acetylcholine alpha 7-containing receptor complex is linked to memory retrieval in the multiple-T-maze in C57BL/6j mice.

    Science.gov (United States)

    Subramaniyan, Saraswathi; Heo, Seok; Patil, Sudarshan; Li, Lin; Hoger, Harald; Pollak, Arnold; Lubec, Gert

    2014-08-15

    The link between the cholinergic and serotonergic system in cognitive function is well-documented. There is, however, limited information on spatial memory and this formed the rationale to carry out a study with the aim to show a specific link between nicotinic and serotonergic receptor complexes rather than the corresponding subunits, to spatial memory retrieval in a land maze. A total of 46 mice were used and divided into two groups, trained and untrained (yoked) in the multiple-T-Maze (MTM) and following training during the first four days, probe trials for memory retrieval were performed on days 8, 16 and 30. Six hours following scarification, hippocampi were taken for the analysis of native receptor complex levels using blue-native gels followed by immunoblotting with specific antibodies. 5-HT1A-, 5-HT7-, nAChα4- and nACh-α7-containing receptor complexes were observed and were paralleling memory retrievals and receptor complex levels were shown to be significantly different between trained and yoked animals. Only levels of a nicotinic acetylcholine α7 receptor-containing complex at an apparent molecular weight of approximately 480kDa were shown to be linked to memory retrieval on day 8 but not to retrievals on days 16 and 30 when memory extinction has taken place. Correlation between nAChα4-, 5-HT1A- and 5-HT7-containing receptors and latencies on day 16 may point to a probable link in extinction mechanisms. A series of the abovementioned receptor complexes were correlating among each other probably indicating a serotonergic/cholinergic network paralleling spatial memory formation.

  18. The Effect of an NCAM Mimetic on Learning and Memory Impairment in an Animal Model of Schizophrenia

    DEFF Research Database (Denmark)

    Secher, Thomas

    2009-01-01

    for schizophrenia. Neonatal treatment with the N-methyl-D-aspartate (NMDA) receptor antagonist phencyclidine (PCP) on postnatal days 7, 9, and 11 has been shown to induce acute neurodegeneration and long-term cognitive deficits and other behavioral abnormalities relevant to schizophrenia. To evaluate the effect...... of FGL in this model, adult PCP rats were tested for spatial reference memory, reversal learning, and working memory deficits in Morris’ water maze in combination with different FGL treatment regimens. Two doses of PCP (10 and 30 mg/kg) were tested. Behavioral testing was complemented...... by immunohistochemical investigation of neurodegeneration and NMDA receptor activation in relevant brain regions. The results show that neonatal PCP treatment induces long-term impairment in spatial learning and memory. The higher PCP dose produced more robust deficits in all three tasks of the water maze, whereas...

  19. β-adrenergic modulation of in vivo long-term potentiation in area CA1 and its role in spatial learning in rats

    Institute of Scientific and Technical Information of China (English)

    JI; Jinzhao; (季今朝); ZHANG; Xuehan; (张雪寒); LI; Baoming; (李葆明)

    2003-01-01

    Activation of β-adrenoceptors in area CA1 of the hippocampus facilitates in vitro long-term potentiation (LTP) in this region. However, it is unclear if in vivo LTP in area CA1 and hippocampus-dependent learning are subjected to β-adrenergic regulation. To address this question, we investigated the effects of the β-adrenergic agonist L-isoproterenol or antagonist DL-propranolol on in vivo LTP of area CA1 and the spatial learning in Morris water maze. In the presence of L-isoproterenol (through local infusion into area CA1), the theta-pulse stimulation with the parameter of 10 Hz, 150 pulses/train, 1 train, a frequency weakly modifying synaptic strength, induced a robust LTP, and this effect was blocked when DL-propranolol was co-administered. By contrast, the theta-pulse stimulation with the parameter of 5 Hz, 150 pulses/train, 3 trains, a frequency strongly modifying synaptic strength, induced a significantly smaller LTP when DL-propranolol was administered into area CA1. Accordingly, DL-propranolol impaired the spatial learning in the water maze when infused into area CA1 20 min pretraining. Compared with control rats, the DL-propranolol-treated rats showed significantly slower learning in the water maze and subsequently exhibited poor memory retention at 24-h test. These results suggest that β-adrenoceptors in area CA1 are involved in regulating in vivo synaptic plasticity of this area and are important for spatial learning.

  20. Serial position learning in honeybees.

    Directory of Open Access Journals (Sweden)

    Randolf Menzel

    Full Text Available Learning of stimulus sequences is considered as a characteristic feature of episodic memory since it contains not only a particular item but also the experience of preceding and following events. In sensorimotor tasks resembling navigational performance, the serial order of objects is intimately connected with spatial order. Mammals and birds develop episodic(-like memory in serial spatio-temporal tasks, and the honeybee learns spatio-temporal order when navigating between the nest and a food source. Here I examine the structure of the bees' memory for a combined spatio-temporal task. I ask whether discrimination and generalization are based solely on simple forms of stimulus-reward learning or whether they require sequential configurations. Animals were trained to fly either left or right in a continuous T-maze. The correct choice was signaled by the sequence of colors (blue, yellow at four positions in the access arm. If only one of the possible 4 signals is shown (either blue or yellow, the rank order of position salience is 1, 2 and 3 (numbered from T-junction. No learning is found if the signal appears at position 4. If two signals are shown, differences at positions 1 and 2 are learned best, those at position 3 at a low level, and those at position 4 not at all. If three or more signals are shown these results are corroborated. This salience rank order again appeared in transfer tests, but additional configural phenomena emerged. Most of the results can be explained with a simple model based on the assumption that the four positions are equipped with different salience scores and that these add up independently. However, deviations from the model are interpreted by assuming stimulus configuration of sequential patterns. It is concluded that, under the conditions chosen, bees rely most strongly on memories developed during simple forms of associative reward learning, but memories of configural serial patterns contribute, too.

  1. Curiosity driven reinforcement learning for motion planning on humanoids

    OpenAIRE

    Mikhail eFrank; Jürgen eLeitner; Marijn eStollenga; Alexander eFörster; Jürgen eSchmidhuber

    2014-01-01

    Most previous work on textit{artificial curiosity} and textit{intrinsic motivation} focuses on basic concepts and theory. Experimental results are generally limited to toy scenarios, such as navigation in a simulated maze, or control of a simple mechanical system with one or two degrees of freedom. To study artificial curiosity in a more realistic setting, we emph{embody} a curious agent in the complex iCub humanoid robot. Our novel reinforcement learning framework consists of a state-of-the...

  2. Effect of combination of Phyllanthus emblica, Tinospora cordifolia, and Ocimum sanctum on spatial learning and memory in rats

    OpenAIRE

    2014-01-01

    Background: There has been a steady rise in number of patients suffering from dementia including dementia associated with Alzheimer's disease. Effective treatment of Alzheimer's disease dementia is an unmet medical need. Objective: To evaluate effects of formulation containing combination of Phyllanthus emblica (Pe) and Tinospora cordifolia (Tc) with and without Ocimum sanctum (Os) on learning and memory performance of normal and memory impaired rats in complex maze and compare with effects o...

  3. 基于IEEE标准电脑鼠走迷宫控制算法研究与优化%Research and Optimization of Control Algorithm for Micro-Mouse Solving the Maze Based on IEEE Criterion

    Institute of Scientific and Technical Information of China (English)

    郑伟; 张永飞

    2016-01-01

    结合IEEE标准电脑鼠走迷宫竞赛的要求,为了进一步提高电脑鼠的性能,在对电脑鼠软硬件系统做深入研究的基础上,优化了电脑鼠走迷宫控制算法。通过10个随机迷宫实验,结果显示优化后电脑鼠迷宫冲刺时间平均减少了37.2%。%Combined with the requirements of IEEE criterion on solving the maze in micro-mouse contest, and in order to improve the performance of micro-mouse, the control algorithm of solving the maze has been optimized on the basis of researching the mi⁃cro-mouse’s systems of software and hardware. By conducting experiments with 10 random mazes, the results demonstrate that the average time of spurting in the maze reduces by 37.2%.

  4. THE USE OF THE ELEVATED PLUS MAZE IN THE TOXICOLOGY LABORAOTRY: PILOT STUDIES AND ASSESSMENT OF ANXIETY IN RATS EXPOSED TO LEAD ACETATE OR SUB-CHRONIC LEVELS OF TOLUENE.

    Science.gov (United States)

    A common complaint of individuals exposed to neurotoxic agents is increased anxiety. Rat models of the effects of long-term exposure to environmental chemicals on anxiety are lacking. The elevated plus-maze (EPM) is a widely used tool in the search for new

  5. Learning to use working memory: a reinforcement learning gating model of rule acquisition in rats

    Directory of Open Access Journals (Sweden)

    Kevin eLloyd

    2012-10-01

    Full Text Available Learning to form appropriate, task-relevant working memory representations is a complex process central to cognition. Gating models frame working memory as a collection of past observations and use reinforcement learning to solve the problem of when to update these observations. Investigation of how gating models relate to brain and behavior remains, however, at an early stage. The current study sought to explore the ability of simple reinforcement learning gating models to replicate rule learning behavior in rats. Rats were trained in a maze-based spatial learning task that required animals to make trial-by-trial choices contingent upon their previous experience. Using an abstract version of this task, we tested the ability of two gating algorithms, one based on the Actor-Critic and the other on the State-Action-Reward-State-Action (SARSA algorithm, to generate behavior consistent with the rats’. Both models produced rule-acquisition behavior consistent with the experimental data, though only the SARSA gating model mirrored faster learning following rule reversal. We also found that both gating models learned multiple strategies in solving the initial task, a property which highlights the multi-agent nature of such models and which is of importance in considering the neural basis of individual differences in behavior.

  6. Learning and memory enhancing activity of Ficus carica (Fig: An experimental study in rats

    Directory of Open Access Journals (Sweden)

    Meera Sumanth

    2014-01-01

    Full Text Available Objective: The study aimed to assess the learning and memory enhancing activity of the ethanolic fruit extract of Ficus carica in rats using elevated plus maze (EPM, Hebb-William maze (HWM and Morris water maze (MWM. Materials and Methods: Wistar rats (100-150 g of either sex, were divided into 5 groups (n = 6. Group I (control animals received vehicle, Group II (scopolamine control animals received scopolamine (0.4 mg/kg i.p, Groups III and IV animals received ethanolic fruit extract of F. carica (200 mg/kg and 400 mg/kg p.o and Group V animals received piracetam (400 mg/kg i.p for 27 days. The rats of Groups III-V were injected with a single dose of scopolamine (0.4 mg/kg i.p on 19 th and 27 th day. Assessment of transfer latency (TL, time taken to reach reward chamber (TRC and swim latency (SL was done on 19 th and 27 th day using EPM, HWM and MWM, respectively. The data was analyzed by one-way Analysis of Variance followed by Dunnett′s test. P ≤ 0.05 was considered to be significant. Results: Ethanolic fruit extract of F. carica decreased TL, TRC and SL in comparison to scopolamine treated rats. Conclusion: The fruit of F. carica enhanced learning and memory activity.

  7. Chronic BDNF deficiency leads to an age-dependent impairment in spatial learning.

    Science.gov (United States)

    Petzold, Anne; Psotta, Laura; Brigadski, Tanja; Endres, Thomas; Lessmann, Volkmar

    2015-04-01

    Brain-derived neurotrophic factor (BDNF) is a crucial mediator of neural plasticity and, consequently, of memory formation. In hippocampus-dependent learning tasks BDNF also seems to play an essential role. However, there are conflicting results concerning the spatial learning ability of aging BDNF(+/-) mice in the Morris water maze paradigm. To evaluate the effect of chronic BDNF deficiency in the hippocampus on spatial learning throughout life, we conducted a comprehensive study to test differently aged BDNF(+/-) mice and their wild type littermates in the Morris water maze and to subsequently quantify their hippocampal BDNF protein levels as well as expression levels of TrkB receptors. We observed an age-dependent learning deficit in BDNF(+/-) animals, starting at seven months of age, despite stable hippocampal BDNF protein expression and continual decline of TrkB receptor expression throughout aging. Furthermore, we detected a positive correlation between hippocampal BDNF protein levels and learning performance during the probe trial in animals that showed a good learning performance during the long-term memory test.

  8. Can personality predict individual differences in brook trout spatial learning ability?

    Science.gov (United States)

    White, S L; Wagner, T; Gowan, C; Braithwaite, V A

    2017-08-01

    While differences in individual personality are common in animal populations, understanding the ecological significance of variation has not yet been resolved. Evidence suggests that personality may influence learning and memory; a finding that could improve our understanding of the evolutionary processes that produce and maintain intraspecific behavioural heterogeneity. Here, we tested whether boldness, the most studied personality trait in fish, could predict learning ability in brook trout. After quantifying boldness, fish were trained to find a hidden food patch in a maze environment. Stable landmark cues were provided to indicate the location of food and, at the conclusion of training, cues were rearranged to test for learning. There was a negative relationship between boldness and learning as shy fish were increasingly more successful at navigating the maze and locating food during training trials compared to bold fish. In the altered testing environment, only shy fish continued using cues to search for food. Overall, the learning rate of bold fish was found to be lower than that of shy fish for several metrics suggesting that personality could have widespread effects on behaviour. Because learning can increase plasticity to environmental change, these results have significant implications for fish conservation. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Representation of actions in rats: the role of cerebellum in learning spatial performances by observation.

    Science.gov (United States)

    Leggio, M G; Molinari, M; Neri, P; Graziano, A; Mandolesi, L; Petrosini, L

    2000-02-29

    Experimental evidence demonstrates that cerebellar networks are involved in spatial learning, controlling the acquisition of exploration strategies without blocking motor execution of the task. Action learning by observation has been considered somehow related to motor physiology, because it provides a way of learning performances that is almost as effective as the actual execution of actions. Neuroimaging studies demonstrate that observation of movements performed by others, imagination of actions, and actual execution of motor performances share common neural substrates and that the cerebellum is among these shared areas. The present paper analyzes the effects of observation in learning a spatial task, focusing on the cerebellar role in learning a spatial ability through observation. We allowed normal rats to observe 200 Morris water maze trials performed by companion rats. After this observation training, "observer" rats underwent a hemicerebellectomy and then were tested in the Morris water maze. In spite of the cerebellar lesion, they displayed no spatial defects, exhibiting exploration abilities comparable to controls. When the cerebellar lesion preceded observation training, a complete lack of spatial observational learning was observed. Thus, as demonstrated already for the acquisition of spatial procedures through actual execution, cerebellar circuits appear to play a key role in the acquisition of spatial procedures also through observation. In conclusion, the present results provide strong support for a common neural basis in the observation of actions that are to be reproduced as well as in the actual production of the same actions.

  10. EFFECT OF EXERCISE ON LEARNING, MEMORY AND LEVELS OF EPINEPHRINE IN RATS' HIPPOCAMPUS

    Directory of Open Access Journals (Sweden)

    Hojjatallah Alaei

    2003-09-01

    Full Text Available The aim of the present study was to investigate effect of exercise on learning and memory, long-term potentiation and levels of epinephrine in the rat hippocampus. Treadmill trained (one hour at 17 m·min-1 for 10 days and corresponding control rats went through spatial learning process on a Morris water maze for 8 days. The time to reach the platform (latency, the length of swim path, and the swim speed were used for the evaluation of spatial learning. Our results showed that physical activity produced a significant enhancement in spatial learning, with a decreased path length (p<0.05 and latency (p<0.05 to the platform in Morris water maze, without affecting the swim speed. Furthermore, the levels of the epinephrine were significantly increased (p<0.05 in hippocampus of the exercised rats. In conclusion our findings suggest that the enhanced learning by exercise may be mediated through the activation of adrenoceptors in the hippocampus and epinephrine may play an important role in potentiation of learning

  11. The effects of phencyclidine (PCP) on anxiety-like behavior in the elevated plus maze and the light-dark exploration test are age dependent, sexually dimorphic, and task dependent.

    Science.gov (United States)

    Turgeon, Sarah M; Kim, Daniel; Pritchard, Melissa; Salgado, Sanjay; Thaler, Alison

    2011-11-01

    Previous research in our laboratory revealed sexually dimorphic effects of prior exposure to phencyclidine (PCP) on elevated plus maze behavior. In an attempt to examine the developmental time course of this effect and determine the extent to which it generalizes to other anxiety paradigms, young adult (61-64 days old) and adult (96-107 days old) male and female rats were treated with PCP (15 mg/kg) or saline. Following a two week withdrawal period, animals were tested in either the elevated plus maze (EPM) or a light-dark exploration (LD) test. In adults, both tests revealed a sexually dimorphic effect driven by PCP-induced decreases in anxiety in females as indicated by increased time spent in the open arms of the EPM and in the lit compartment of the LD test and increased anxiety in males as indicated by decreased time spent in the lit compartment of the LD. In young animals, PCP pretreatment decreased open arm exploration in the elevated plus maze, indicating increased anxiety. However, PCP increased time spent in the light compartment in the light-dark exploration test, indicating decreased anxiety. Corticosterone levels measured 15 min after the onset of the EPM failed to reveal an association between the behavioral effects of PCP and corticosterone levels. The results in adults substantiate the previously observed sexually dimorphic effect of PCP on elevated plus maze behavior in adults and indicate that the effect generalizes to another anxiety paradigm. The results in the younger animals suggest an age dependent effect of PCP on anxiety in general and indicate that behaviors in the elevated plus maze and the light-dark exploration test reflect dissociable psychobiological states. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter

    2011-01-01

    Sloep, P. B. (2011). Learning Networks, Networked Learning. Presentation at Annual Assembly of the European Society for the Systemic Innovation of Education - ESSIE. May, 27, 2011, Leuven, Belgium: Open University in the Netherlands.

  13. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  14. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  15. Effect of intranasal manganese administration on neurotransmission and spatial learning in rats

    Energy Technology Data Exchange (ETDEWEB)

    Blecharz-Klin, Kamilla; Piechal, Agnieszka; Joniec-Maciejak, Ilona; Pyrzanowska, Justyna; Widy-Tyszkiewicz, Ewa, E-mail: etyszkiewicz@wum.edu.pl

    2012-11-15

    The effect of intranasal manganese chloride (MnCl{sub 2}·4H{sub 2}O) exposure on spatial learning, memory and motor activity was estimated in Morris water maze task in adult rats. Three-month-old male Wistar rats received for 2 weeks MnCl{sub 2}·4H{sub 2}O at two doses the following: 0.2 mg/kg b.w. (Mn0.2) or 0.8 mg/kg b.w. (Mn0.8) per day. Control (Con) and manganese-exposed groups were observed for behavioral performance and learning in water maze. ANOVA for repeated measurements did not show any significant differences in acquisition in the water maze between the groups. However, the results of the probe trial on day 5, exhibited spatial memory deficits following manganese treatment. After completion of the behavioral experiment, the regional brain concentrations of neurotransmitters and their metabolites were determined via HPLC in selected brain regions, i.e. prefrontal cortex, hippocampus and striatum. ANOVA demonstrated significant differences in the content of monoamines and metabolites between the treatment groups compared to the controls. Negative correlations between platform crossings on the previous platform position in Southeast (SE) quadrant during the probe trial and neurotransmitter turnover suggest that impairment of spatial memory and cognitive performance after manganese (Mn) treatment is associated with modulation of the serotonergic, noradrenergic and dopaminergic neurotransmission in the brain. These findings show that intranasally applied Mn can impair spatial memory with significant changes in the tissue level and metabolism of monoamines in several brain regions. -- Highlights: ► Intranasal exposure to manganese in rats impairs spatial memory in the water maze. ► Regional changes in levels of neurotransmitters in the brain have been identified. ► Cognitive disorder correlates with modulation of 5-HT, NA and DA neurotransmission.

  16. In search of intelligence: evolving a developmental neuron capable of learning

    Science.gov (United States)

    Khan, Gul Muhammad; Miller, Julian Francis

    2014-10-01

    A neuro-inspired multi-chromosomal genotype for a single developmental neuron capable of learning and developing memory is proposed. This genotype is evolved so that the phenotype which changes and develops during an agent's lifetime (while problem-solving) gives the agent the capacity for learning by experience. Seven important processes of signal processing and neural structure development are identified from biology and encoded using Cartesian Genetic Programming. These chromosomes represent the electrical and developmental aspects of dendrites, axonal branches, synapses and the neuron soma. The neural morphology that occurs by running these chromosomes is highly dynamic. The dendritic/axonal branches and synaptic connections form and change in response to situations encountered in the learning task. The approach has been evaluated in the context of maze-solving and the board game of checkers (draughts) demonstrating interesting learning capabilities. The motivation underlying this research is to, ab initio, evolve genotypes that build phenotypes with an ability to learn.

  17. Mice with deficient BK channel function show impaired prepulse inhibition and spatial learning, but normal working and spatial reference memory.

    Directory of Open Access Journals (Sweden)

    Marei Typlt

    Full Text Available Genetic variations in the large-conductance, voltage- and calcium activated potassium channels (BK channels have been recently implicated in mental retardation, autism and schizophrenia which all come along with severe cognitive impairments. In the present study we investigate the effects of functional BK channel deletion on cognition using a genetic mouse model with a knock-out of the gene for the pore forming α-subunit of the channel. We tested the F1 generation of a hybrid SV129/C57BL6 mouse line in which the slo1 gene was deleted in both parent strains. We first evaluated hearing and motor function to establish the suitability of this model for cognitive testing. Auditory brain stem responses to click stimuli showed no threshold differences between knockout mice and their wild-type littermates. Despite of muscular tremor, reduced grip force, and impaired gait, knockout mice exhibited normal locomotion. These findings allowed for testing of sensorimotor gating using the acoustic startle reflex, as well as of working memory, spatial learning and memory in the Y-maze and the Morris water maze, respectively. Prepulse inhibition on the first day of testing was normal, but the knockout mice did not improve over the days of testing as their wild-type littermates did. Spontaneous alternation in the y-maze was normal as well, suggesting that the BK channel knock-out does not impair working memory. In the Morris water maze knock-out mice showed significantly slower acquisition of the task, but normal memory once the task was learned. Thus, we propose a crucial role of the BK channels in learning, but not in memory storage or recollection.

  18. Selective breeding for endurance running capacity affects cognitive but not motor learning in rats.

    Science.gov (United States)

    Wikgren, Jan; Mertikas, Georgios G; Raussi, Pekka; Tirkkonen, Riina; Äyräväinen, Laura; Pelto-Huikko, Markku; Koch, Lauren G; Britton, Steven L; Kainulainen, Heikki

    2012-05-15

    The ability to utilize oxygen has been shown to affect a wide variety of physiological factors often considered beneficial for survival. As the ability to learn can be seen as one of the core factors of survival in mammals, we studied whether selective breeding for endurance running, an indication of aerobic capacity, also has an effect on learning. Rats selectively bred over 23 generations for their ability to perform forced treadmill running were trained in an appetitively motivated discrimination-reversal classical conditioning task, an alternating T-maze task followed by a rule change (from a shift-win to stay-win rule) and motor learning task. In the discrimination-reversal and T-maze tasks, the high-capacity runner (HCR) rats outperformed the low-capacity runner (LCR) rats, most notably in the phases requiring flexible cognition. In the Rotarod (motor-learning) task, the HCR animals were overall more agile but learned at a similar rate with the LCR group as a function of training. We conclude that the intrinsic ability to utilize oxygen is associated especially with tasks requiring plasticity of the brain structures implicated in flexible cognition.

  19. Role of state-dependent learning in the cognitive effects of caffeine in mice.

    Science.gov (United States)

    Sanday, Leandro; Zanin, Karina A; Patti, Camilla L; Fernandes-Santos, Luciano; Oliveira, Larissa C; Longo, Beatriz M; Andersen, Monica L; Tufik, Sergio; Frussa-Filho, Roberto

    2013-08-01

    Caffeine is the most widely used psychoactive substance in the world and it is generally believed that it promotes beneficial effects on cognitive performance. However, there is also evidence suggesting that caffeine has inhibitory effects on learning and memory. Considering that caffeine may have anxiogenic effects, thus changing the emotional state of the subjects, state-dependent learning may play a role in caffeine-induced cognitive alterations. Mice were administered 20 mg/kg caffeine before training and/or before testing both in the plus-maze discriminative avoidance task (an animal model that concomitantly evaluates learning, memory, anxiety-like behaviour and general activity) and in the inhibitory avoidance task, a classic paradigm for evaluating memory in rodents. Pre-training caffeine administration did not modify learning, but produced an anxiogenic effect and impaired memory retention. While pre-test administration of caffeine did not modify retrieval on its own, the pre-test administration counteracted the memory deficit induced by the pre-training caffeine injection in both the plus-maze discriminative and inhibitory avoidance tasks. Our data demonstrate that caffeine-induced memory deficits are critically related to state-dependent learning, reinforcing the importance of considering the participation of state-dependency on the interpretation of the cognitive effects of caffeine. The possible participation of caffeine-induced anxiety alterations in state-dependent memory deficits is discussed.

  20. Modulatory effects of dopamine receptors on associative learning performance in zebrafish (Danio rerio).

    Science.gov (United States)

    Naderi, Mohammad; Jamwal, Ankur; Chivers, Douglas P; Niyogi, Som

    2016-04-15

    The zebrafish (Danio rerio) has been shown to be an insatiable rival for mammalian model organisms, in many research areas including behavioral neuroscience. Despite a growing body of evidence on successful performance of zebrafish in learning paradigms, little progress has been made toward elucidating the role of neuromodulatory systems in regulation of cognitive functions in this species. Here, we investigated the modulatory effect of dopamine, one of the major neurotransmitters of importance in the brain, on cognitive performance of zebrafish. To this end, a plus maze associative learning paradigm was employed where fish trained to associate a conditioned visual stimulus with the sight of conspecifics as the rewarding unconditioned stimulus. Experimental fish were exposed to dopaminergic agonists (SKF-38393 and quinpirole) and antagonists (SCH-23390 and eticlopride) immediately before training, after training, and just before probe. Pre- and post-training administration of SKF-38393 and SCH-23390 enhanced learning and memory performance of zebrafish in the maze but not when given immediately before the probe trial. Quinpirole also enhanced probe trial performance when administered immediately before training and before the probe but not when given after training. Furthermore, fish that received eticlopride before training, after training or before the probe showed impairment in associative learning performance. Taken together, our results shed first light on modulatory role of dopamine receptors in different aspects of learning and memory in zebrafish.

  1. Histamine ameliorates spatial memory deficits induced by MK-801 infusion into ventral hippocampus as evaluated by radial maze task in rats

    Institute of Scientific and Technical Information of China (English)

    Li-sha XU; Li-xia YANG; Wei-wei HU; Xiao YU; Li MA; Lu-ying LIU; Er-qing WEI; Zhong CHEN

    2005-01-01

    Aim: To investigate the role of histamine in memory deficits induced by MK-801 infusion into the ventral hippocampus in rats. Methods: An 8-arm radial maze (4arms baited) was used to assess spatial memory. Results: Bilateral ventral intrahippocampal (ih) infusion of MK-801 (0.3 μg/site), an N-methyl-D-aspartate (NMDA) antagonist, impaired the retrieval process in both working memory and reference memory. Intrahippocampal injection of histamine (25 or 50 ng/site) or intraperitoneal (ip) injection of histidine (25, 50 or 100 mg/kg) markedly ameliorated the spatial memory deficits induced by MK-801. Both the histamine H1 antagonist pyrilamine (0.5 or 1.0 μg/site, ih) and the H2 antagonist cimetidine (2.5 μg/site,ih) abolished the ameliorating effect of histidine (100 mg/kg, ip) on reference memory deficits, but not that on working memory deficits induced by MK-801. Conclusion:The results indicate that histamine in the ventral hippocampus can ameliorate MK-801-induced spatial memory deficits, and that histamine's effect on reference memory is mediated by postsynaptic histamine H1 and H2 receptors.

  2. Anxiolytic Effect Evaluation of Methanol Extract of Ceplukan Leaves in the Elevated Plus Maze Test through IL-6 Level Changes in Ovariectomized Rat

    Directory of Open Access Journals (Sweden)

    Siti Nurfitria

    2015-01-01

    Full Text Available Ceplukan (Physalis minima L. has long been used to treat various conditions in traditional medicine. This study aims to demonstrate the anxiolytic effects of Methanol Extract of Ceplukan Leaves (MECL in the Elevated Plus Maze (EPM test and correlate to IL-6 level of ovariectomized rat brain. Total of 24 Wistar rats were divided into six groups: one normal group, one group of 1 month ovariectomized (ovx, one group of 2 months ovx, three groups of 2 months ovx (each given with MECL 500; 1500 and 2500 mg/kg doses for 1 month. The anxiety-like behavior level was measured by EPM test. After EPM test, the brain was removed to measure level of IL-6 by ELISA. The data were processed and analyzed by one-way ANOVA and Pearson correlation. We found that the MECL-treated rats enter the opened-arm higher than the control rats. It indicates that the MECL-treated rats are less anxious than the control rats. The results also show the decreased of IL-6 level in MECL-treated rats.

  3. Solution for the Maze Game Based on Multi-Agent Genetic Algorithm%基于多Agent遗传算法求解迷宫游戏

    Institute of Scientific and Technical Information of China (English)

    李少保; 赵春晓

    2011-01-01

    游戏设计的实质是设计一些相互关联的游戏规则.通过分析迷宫游戏元素之间的关系,抽象制定出一套游戏规则,并在此基础上,提出了一种以寻路个体为单个智能体的多Agent遗传算法.通过C++进行模拟仿真,实验结果验证了所提优化算法的合理性;与传统的遗传算法相比,此算法在避免早熟的同时有很快的全局收敛性.%The essence of game design is to design some related rules of the game.On the basis of the analysis of relationships among various elements in the maze game,a set of rules of the game is worked out abstractly in the paper.Then a multi-agent genetic algorithm,in which the individual of finding the maze's path is as an agent,is proposed.At last it is simulated by C++ and compared with the traditional genetic algorithm.The simulation results indicate that the proposed optimization model is reasonable and this algorithm can avoid precocious phenomena and have quicker convergence rate and better global astringency.

  4. The Maze Runner%《移动迷宫》--唯有直面黑暗,才能重见光明

    Institute of Scientific and Technical Information of China (English)

    侯德鸷

    2015-01-01

    近几年,有越来越多根据青少年畅销小说改编的科幻电影登上了大银幕,不仅赚足了观众的眼球,也将这类反乌托邦题材的电影推向了潮流的尖端。这部改编自美国作家James Dashner同名科幻小说的电影《移动迷宫》(The Maze Runner)便是其中的佼佼者。不过,比起其他同样聚焦于反乌托邦题材的影片,本片的故事内容则更加阴暗。除此之外,影片还采用了惊悚悬疑的叙事风格,使故事更加扣人心弦。看着影片中的主人公们展开一段惊险刺激的逃亡之旅,我们不但为他们的智慧和身手叫好,更为他们的成长和友谊称赞。迷宫在移动,我们也和这些主人公一起收获一份特有的感动……

  5. Effects of periadolescent fluoxetine and paroxetine on elevated plus-maze, acoustic startle, and swimming immobility in rats while on and off-drug

    Directory of Open Access Journals (Sweden)

    Williams Michael T

    2011-10-01

    Full Text Available Abstract Rationale Whether selective serotonin reuptake inhibitors (SSRIs exposure during adolescent brain development causes lasting effects remains unresolved. Objective Assess the effects of fluoxetine and paroxetine 60 days after adolescent exposure compared with when on-drug. Methods Male Sprague-Dawley littermates (41 litters were gavaged on postnatal days 33-53 with fluoxetine (3 or 10 mg/kg/day, paroxetine (3, 10 or, 17 mg/kg/day, or water; half were tested while on-drug (21 litters and half after 60 days off-drug (20 litters. Results The highest dose of the drugs reduced body weight gain during treatment that rebounded 1 week post-treatment. On-drug, no significant group differences were found on elevated plus maze time-in-open, zone entries, or latency to first open entry; however, the high dose of paroxetine significantly reduced head-dips (N = 20/group. No significant effects were found on-drug for acoustic startle response/prepulse inhibition (ASR/PPI although a trend (p Conclusions The data provide no evidence that fluoxetine or paroxetine have long-term adverse effects on the behaviors measured here after adolescent to young adult exposure.

  6. 电脑鼠走迷宫中坐标与方向的处理%the realization of micromouse maze in Center algorithm

    Institute of Scientific and Technical Information of China (English)

    叶高杨; 王福平; 祝玲; 许丹丹

    2014-01-01

    This paper introduces the central algorithm, practical platform on a computer mouse Maze Robot Based Guangzhou Zhiyuan Electronics design and production of a computer mouse, it uses NXP microcontroler produced Cotex_M3 core ARM processor - LPC1752. As a micromouse core competencies - algorithm, which directly affects the performance of the pros and cons of a computer mouse. Center algorithm is a computer algorithm, the number of racing popular choice, this article wil briefly Knowledge Center algorithm developed for the computer mouse has a reference.%该文主要介绍了中心算法在电脑鼠走迷宫机器人上的应用,实用平台基于广州致远电子设计生产的一款电脑鼠,它的微控制器采用NXP公司生产的Cotex_M3内核ARM处理器--LPC1752。作为电脑鼠的核心竞争力--算法,其优劣性直接影响电脑鼠的性能。中心算法是电脑数竞速算法中热门之选,该文将简单介绍中心算法的知识,对电脑鼠开发有借鉴意义。

  7. Maze of Photography Curator Rules and Ethical Bottomline%摄影策展:规则的谜局与伦理的底线

    Institute of Scientific and Technical Information of China (English)

    孙宇龙

    2012-01-01

    Photography curator of the market, creation of industrialization, the conceptulization of content, works of photography have become a standardized commercial capital mode of operation. Photography became a capital operation in the chain, photography, marketing, consumption and recreation of Loop, curator of sales in the form into the core part of this paper to explore this part of the curatorial judgments behind the maze of rules, the evolution of the hidden art of ethical moral bottom line with visual consumption.%摄影策展的市场化、创作工业化、内容的观念化、作品的商品化让摄影展示成为规范化资本运作模式,摄影创作成为资本运营中一个链条,摄影创作、销售、消费和再创作的循环中,策展以“销售”形式成其核心环节,本文通过对这一环节的探究来研判策展背后的规则谜局、艺术伦理的隐性演变与视觉消费的道德底线。

  8. Serotonin-1A receptors in the dorsal periaqueductal gray matter mediate the panicolytic-like effect of pindolol and paroxetine combination in the elevated T-maze.

    Science.gov (United States)

    Sela, Vânia Ramos; Biesdorf, Carla; Ramos, Diego Henrique; Zangrossi, Hélio; Graeff, Frederico Guilherme; Audi, Elisabeth Aparecida

    2011-05-01

    The β-adrenergic blocker and 5-HT(1A) receptor antagonist pindolol has been combined with selective serotonin reuptake inhibitors (SSRIs) in patients with depressive and anxiety disorders to shorten the onset of the clinical action and/or increase the proportion of responders. The results of a previous study have shown that pindolol potentiates the panicolytic effect of paroxetine in rats submitted to the elevated T-maze (ETM). Since reported evidence has implicated the 5-HT(1A) receptors of the dorsal periaqueductal gray matter (DPAG) in the panicolytic effect of antidepressants, rats treated with pindolol (5.0mg/kg, i.p.) and paroxetine (1.5mg/kg, i.p.) received a previous intra-DPAG injection of the selective 5-HT(1A) antagonist, WAY-100635 (0.4 μg) and were submitted to the ETM. Pretreatment with WAY-100635 reversed the increase in escape latency, a panicolytic effect, determined by the pindolol-paroxetine combination. These results implicate the 5-HT(1A) receptors of the DPAG in the panicolytic effect of the pindolol-paroxetine combination administered systemically. They also give further preclinical support for the use of this drug combination in the treatment of panic disorder.

  9. NMDA and D1 receptors are involved in one-trial tolerance to the anxiolytic-like effects of diazepam in the elevated plus maze test in rats.

    Science.gov (United States)

    Zhou, Heng; Yu, Cheng-Long; Wang, Li-Ping; Yang, Yue-Xiong; Mao, Rong-Rong; Zhou, Qi-Xin; Xu, Lin

    2015-08-01

    The elevated plus maze (EPM) test is used to examine anxiety-like behaviors in rodents. One interesting phenomenon in the EPM test is one-trial tolerance (OTT), which refers to the reduction in the anxiolytic-like effects of benzodiazepines when rodents are re-exposed to the EPM. However, the underlying mechanism of OTT is still unclear. In this study, we reported that OTT occurred when re-exposure to the EPM (trial 2) only depended on the prior experience of the EPM (trial 1) rather than diazepam treatment. This process was memory-dependent, as it was prevented by the N-methyl-D-aspartate (NMDA) receptors antagonist MK-801 1.5h before trial 2. In addition, OTT was maintained for at least one week but was partially abolished after an interval of 28 days. Furthermore, the administration of the D1-like receptors agonist SKF38393 to the bilateral dorsal hippocampus largely prevented OTT, as demonstrated by the ability of the diazepam treatment to produce significant anxiolytic-like effects in trial 2 after a one-day interval. These findings suggest that OTT to the EPM test may occur via the activation of NMDA receptors and the inactivation of D1-like receptors in certain brain regions, including the hippocampus.

  10. Alpha7 nicotinic acetylcholine receptor activation ameliorates scopolamine-induced behavioural changes in a modified continuous Y-maze task in mice.

    Science.gov (United States)

    Redrobe, John P; Nielsen, Elsebet Ø; Christensen, Jeppe K; Peters, Dan; Timmermann, Daniel B; Olsen, Gunnar M

    2009-01-01

    The alpha7 (alpha7) nicotinic acetylcholine receptor may represent a drug target for the treatment of disorders associated with working memory/attentional dysfunction. We investigated the effects of three distinct alpha7 nicotinic acetylcholine receptor agonists: 2-methyl-5-(6-phenyl-pyridazin-3-yl)-octahydro-pyrrolo[3,4-c]pyrrole (A-582941; 0.01-0.1 mg/kg), 4-bromophenyl 1,4-diazabicyclo(3.2.2) nonane-4-carboxylate (SSR180711; 0.3-3 mg/kg) and N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide (PNU-282987; 1-10 mg/kg), on scopolamine-induced deficits in a modified Y-maze procedure. Mice were forced to choose one of two visually distinct arms, and were confined there for a 5 min exploration period before being allowed to explore both arms for a 2 min test session, immediately thereafter. The time spent in each arm, entries and total distance travelled were recorded using an automated system. Characterisation experiments showed that scopolamine-treated (1 mg/kg) mice spent less time exploring the unfamiliar arm, when compared with vehicle-treated animals. Combination experiments showed that all three alpha7 agonists ameliorated scopolamine-induced changes in unfamiliar arm exploration. In conclusion, the present data support the idea that alpha7 nicotinic acetylcholine receptors may represent an interesting target for the treatment of conditions associated with attentional/working memory dysfunction.

  11. GPR30 activation decreases anxiety in the open field test but not in the elevated plus maze test in female mice.

    Science.gov (United States)

    Anchan, Divya; Clark, Sara; Pollard, Kevin; Vasudevan, Nandini

    2014-01-01

    The GPR30 is a novel estrogen receptor (ER) that is a candidate membrane ER based on its binding to 17β estradiol and its rapid signaling properties such as activation of the extracellular-regulated kinase (ERK) pathway. Its distribution in the mouse limbic system predicts a role for this receptor in the estrogenic modulation of anxiety behaviors in the mouse. A previous study showed that chronic administration of a selective agonist to the GPR30 receptor, G-1, in the female rat can improve spatial memory, suggesting that GPR30 plays a role in hippocampal-dependent cognition. In this study, we investigated the effect of a similar chronic administration of G-1 on behaviors that denote anxiety in adult ovariectomized female mice, using the elevated plus maze (EPM) and the open field test as well as the activation of the ERK pathway in the hippocampus. Although estradiol benzoate had no effect on behaviors in the EPM or the open field, G-1 had an anxiolytic effect solely in the open field that was independent of ERK signaling in either the ventral or dorsal hippocampus. Such an anxiolytic effect may underlie the ability of G-1 to increase spatial memory, by acting on the hippocampus.

  12. Role of thirst and visual barriers in the differential behavior displayed by streptozotocin-treated rats in the elevated plus-maze and the open field test.

    Science.gov (United States)

    Rebolledo-Solleiro, Daniela; Crespo-Ramírez, Minerva; Roldán-Roldán, Gabriel; Hiriart, Marcia; Pérez de la Mora, Miguel

    2013-08-15

    Conflicting results have been obtained by several groups when studying the effects of streptozotocin (STZ)-treated rats in the elevated plus-maze (EPM). Since thirst is a prominent feature in STZ-induced diabetic-like condition, we studied whether the walls of the closed arms of the EPM, by limiting the search for water in the environment, may contribute to the observed differential behavioral outcomes. The aim of this study was to ascertain whether visual barriers within the EPM have an influence on the behavior of STZ-treated rats in this test of anxiety. A striking similarity between STZ-treated (50 mg/kg, i.p., in two consecutive days) and water deprived rats (72 h) was found in exploratory behavior in the EPM, showing an anxiolytic-like profile. However the anxiolytic response of STZ-treated rats exposed to the EPM shifts into an anxiogenic profile when they are subsequently tested in the open-field test, which unlike the EPM is devoid of visual barriers. Likewise, water deprived rats (72 h) also showed an anxiogenic profile when they were exposed to the open-field test. Our results indicate that experimental outcomes based on EPM observations can be misleading when studying physiological or pathological conditions, e.g. diabetes, in which thirst may increase exploratory behavior.

  13. Learning Problems

    Science.gov (United States)

    ... de los dientes Video: Getting an X-ray Learning Problems KidsHealth > For Kids > Learning Problems Print A ... for how to make it better. What Are Learning Disabilities? Learning disabilities aren't contagious, but they ...

  14. Learning Disabilities

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Learning Disabilities KidsHealth > For Teens > Learning Disabilities Print A ... study engineering as he'd hoped? What Are Learning Disabilities? For someone diagnosed with a learning disability, ...

  15. Exposure to activity based anorexia impairs contextual learning in weight-restored rats without affecting spatial learning, taste, anxiety, or dietary-fat preference

    Science.gov (United States)

    Boersma, Gretha J.; Treesukosol, Yada; Cordner, Zachary A.; Kastelein, Anneke; Choi, Pique; Moran, Timothy H.; Tamashiro, Kellie L.

    2016-01-01

    Relapse rates are high amongst cases of Anorexia Nervosa (AN) suggesting that some alterations induced by AN may remain after weight restoration. Objective To study the consequences of AN without confounds of environmental variability, a rodent model of activity based anorexia (ABA) can be employed. We hypothesized that exposure to ABA during adolescence may have long-term consequences in taste function, cognition, and anxiety-like behavior after weight restoration. Methods To test this hypothesis we exposed adolescent female rats to ABA (1.5 hrs food access, combined with voluntary running wheel access) and compared their behavior to that of control rats after weight restoration was achieved. The rats were tested for learning /memory, anxiety, food preference and taste in a set of behavioral tests performed during the light period. Results Our data show that ABA exposure leads to reduced performance during the novel object recognition task, a test for contextual learning, without altering performance in the novel place recognition task or the Barnes maze, both tasks that test spatial learning. Furthermore, we do not observe alterations in unconditioned lick responses to sucrose nor quinine (described by humans as “sweet” and “bitter” respectively). Nor did we find alterations in anxiety-like behavior during an elevated plus maze or an open field test. Finally, preference for a diet high in fat was not altered. Discussion Overall our data suggest that ABA exposure during adolescence impairs contextual learning in adulthood without altering spatial leaning, taste, anxiety, or fat preference. PMID:26711541

  16. Evaluation of cognitive function in healthy older subjects treated with fesoterodine.

    Science.gov (United States)

    Kay, Gary G; Maruff, Paul; Scholfield, David; Malhotra, Bimal; Whelan, Laurence; Darekar, Amanda; Martire, Diane L

    2012-05-01

    To evaluate the cognitive effects of fesoterodine 4 and 8 mg versus placebo in healthy older adults. This was an active- and placebo-controlled, double-blind, double-dummy crossover study conducted using healthy volunteers (aged 65-85 years) with baseline Mini-Mental State Examination score ≥ 26. The study comprised 4 treatment periods: fesoterodine 4 mg for 6 days; fesoterodine 4 mg for 3 days followed by fesoterodine 8 mg for 3 days; placebo for 6 days; and placebo for 6 days with alprazolam 1 mg on day 6. The treatment sequence was randomized, with a 3- to 6-day washout between periods. Subjects completed computer-based cognitive assessments and the Rey Auditory Verbal Learning Test on day 1 (before dosing) and day 6 (after dosing) of each period. The primary endpoint was the Detection task; secondary endpoints were the Identification task, 1-card learning task, Continuous Paired Associate Learning task, Groton Maze Learning Task, and the Rey Auditory Verbal Learning Test. Among 18 subjects in the per protocol set, changes from baseline to day 6 with fesoterodine 4 and 8 mg were not significantly different from placebo for any endpoint (P > 0.05); alprazolam produced significant impairment in all endpoints versus placebo (P fesoterodine and sedation for alprazolam. No sedation was reported with fesoterodine. In healthy older adults, fesoterodine 4 and 8 mg once daily had no statistically significant effects versus placebo on any cognitive function assessed, including memory; alprazolam 1 mg produced statistically significant deterioration.

  17. Differentiation of forebrain and hippocampal dopamine 1-class receptors, D1R and D5R, in spatial learning and memory.

    Science.gov (United States)

    Sariñana, Joshua; Tonegawa, Susumu

    2016-01-01

    Activation of prefrontal cortical (PFC), striatal, and hippocampal dopamine 1-class receptors (D1R and D5R) is necessary for normal spatial information processing. Yet the precise role of the D1R versus the D5R in the aforementioned structures, and their specific contribution to the water-maze spatial learning task remains unknown. D1R- and D5R-specific in situ hybridization probes showed that forebrain restricted D1R and D5R KO mice (F-D1R/D5R KO) displayed D1R mRNA deletion in the medial (m)PFC, dorsal and ventral striatum, and the dentate gyrus (DG) of the hippocampus. D5R mRNA deletion was limited to the mPFC, the CA1 and DG hippocampal subregions. F-D1R/D5R KO mice were given water-maze training and displayed subtle spatial latency differences between genotypes and spatial memory deficits during both regular and reversal training. To differentiate forebrain D1R from D5R activation, forebrain restricted D1R KO (F-D1R KO) and D5R KO (F-D5R KO) mice were trained on the water-maze task. F-D1R KO animals exhibited escape latency deficits throughout regular and reversal training as well as spatial memory deficits during reversal training. F-D1R KO mice also showed perseverative behavior during the reversal spatial memory probe test. In contrast, F-D5R KO animals did not present observable deficits on the water-maze task. Because F-D1R KO mice showed water-maze deficits we tested the necessity of hippocampal D1R activation for spatial learning and memory. We trained DG restricted D1R KO (DG-D1R KO) mice on the water-maze task. DG-D1R KO mice did not present detectable spatial memory deficit, but did show subtle deficits during specific days of training. Our data provides evidence that forebrain D5R activation plays a unique role in spatial learning and memory in conjunction with D1R activation. Moreover, these data suggest that mPFC and striatal, but not DG D1R activation are essential for spatial learning and memory.

  18. Statins Increase Neurogenesis in the Dentate Gyrus, Reduce Delayed Neuronal Death in the Hippocampal CA3 Region, and Improve Spatial Learning in Rat after Traumatic Brain Injury

    OpenAIRE

    Lu, Dunyue; Qu, Changsheng; Goussev, Anton; Jiang, Hao; Lu, Chang; Schallert, Timothy; Mahmood, Asim; Chen, Jieli; Li, Yi; Chopp, Michael

    2007-01-01

    Traumatic brain injury (TBI) remains a major public health problem globally. Presently, there is no way to restore cognitive deficits caused by TBI. In this study, we seek to evaluate the effect of statins (simvastatin and atorvastatin) on the spatial learning and neurogenesis in rats subjected to controlled cortical impact. Rats were treated with atorvastatin and simvastatin 1 day after TBI and daily for 14 days. Morris water maze tests were performed during weeks 2 and 5 after TBI. Bromodeo...

  19. Dietary supplementation of walnuts improves memory deficits and learning skills in transgenic mouse model of Alzheimer's disease.

    Science.gov (United States)

    Muthaiyah, Balu; Essa, Musthafa M; Lee, Moon; Chauhan, Ved; Kaur, Kulbir; Chauhan, Abha

    2014-01-01

    Previous in vitro studies have shown that walnut extract can inhibit amyloid-β (Aβ) fibrillization, can solubilize its fibrils, and has a protective effect against Aβ-induced oxidative stress and cellular death. In this study, we analyzed the effect of dietary supplementation with walnuts on learning skills, memory, anxiety, locomotor activity, and motor coordination in the Tg2576 transgenic (tg) mouse model of Alzheimer's disease (AD-tg). From the age of 4 months, the experimental groups of AD-tg mice were fed custom-mixed diets containing 6% walnuts (T6) or 9% walnuts (T9), i.e., equivalent to 1 or 1.5 oz, respectively, of walnuts per day in humans. The control groups, i.e., AD-tg and wild-type mice, were fed a diet without walnuts (T0, Wt). These experimental and control mice were examined at the ages of 13-14 months by Morris water maze (for spatial memory and learning ability), T maze (for position discrimination learning ability), rotarod (for psychomotor coordination), and elevated plus maze (for anxiety-related behavior). AD-tg mice on the control diet (T0) showed memory deficit, anxiety-related behavior, and severe impairment in spatial learning ability, position discrimination learning ability, and motor coordination compared to the Wt mice on the same diet. The AD-tg mice receiving the diets with 6% or 9% walnuts (T6 and T9) showed a significant improvement in memory, learning ability, anxiety, and motor development compared to the AD-tg mice on the control diet (T0). There was no statistically significant difference in behavioral performance between the T6/T9 mice on walnuts-enriched diets and the Wt group on the control diet. These findings suggest that dietary supplementation with walnuts may have a beneficial effect in reducing the risk, delaying the onset, or slowing the progression of, or preventing AD.

  20. Deletion of glycine transporter 1 (GlyT1) in forebrain neurons facilitates reversal learning: enhanced cognitive adaptability?

    Science.gov (United States)

    Singer, Philipp; Boison, Detlev; Möhler, Hanns; Feldon, Joram; Yee, Benjamin K

    2009-10-01

    Local availability of glycine near N-methyl-D-aspartate receptors (NMDARs) is partly regulated by neuronal glycine transporter 1 (GlyT1), which can therefore modulate NMDAR function because binding to the glycine site of the NMDAR is necessary for channel activation. Disrupting GlyT1 in forebrain neurons has been shown to enhance Pavlovian conditioning and object recognition memory. Here, the authors report that the same genetic manipulation facilitated reversal learning in the water maze test of reference memory, but did not lead to any clear improvement in a working memory version of the water maze test. Facilitation in a nonspatial discrimination reversal task conducted on a T maze was also observed, supporting the conclusion that forebrain neuronal GlyT1 may modulate the flexibility in (new) learning and relevant mnemonic functions. One possibility is that these phenotypes may reflect reduced susceptibility to certain forms of proactive interference. This may be relevant for the suggested clinical application of GlyT1 inhibitors in the treatment of cognitive deficits, including schizophrenia, which is characterized by cognitive inflexibility in addition to the positive symptoms of the disease.

  1. Long-term administration of ginsenoside Rh1 enhances learning and memory by promoting cell survival in the mouse hippocampus.

    Science.gov (United States)

    Hou, Jingang; Xue, Jianjie; Lee, Mira; Yu, Jiaojiao; Sung, Changkeun

    2014-01-01

    Ginsenosides, the secondary plant metabolites produced by Panax ginseng are responsible for the enhancing effects on learning observed following treatment with Panax ginseng. A number of studies have provided correlational evidence that cell proliferation and survival are closely associated with hippocampal-dependent learning tasks. In this study, to investigate the beneficial effects of ginsenoside Rh1 on hippocampal cells and learning, mice (6 months old) were administered ginsenoside Rh1 at a dose of 5 and 10 mg/kg/day for a period of 3 months. Saline-treated mice were used as controls. The enhancement of memory and learning in the mice was evaluated by hippocampal-dependent tasks (passive avoidance tests and Morris water maze tests) and the immunohistochemical marker of cell proliferation, bromodeoxyuridine (BrdU). In addition, the levels of brain-derived neurotrophic factor (BDNF) were measured following treatment. Based on our data, the Rh1-treated group (5 and 10 mg/kg) showed a significantly improved learning and memory ability in the passive avoidance tests compared with the control group; however, only treatment with 10 mg/kg ginsenoside Rh1 significantly promoted spatial learning ability in the Morris water maze test. Ginsenoside Rh1 significantly enhanced cell survival in the dentate gyrus of mice, although it did not enhance hippocampal cell proliferation. In addition, ginsenoside Rh1 upregulated the expression of BDNF. These findings address the potential therapeutic significance of ginsenoside Rh1 as a nutritional supplement in memory loss and neurodegenerative diseases.

  2. 叶酸联合维生素B12对糖尿病大鼠记忆能力及Tau蛋白过度磷酸化影响%Supplementation of folic acid and vitamin B12 prevents the performance in Morris water maze and Alzheimer-like hyperphosphorylation of tau in diabetes mellitus rats

    Institute of Scientific and Technical Information of China (English)

    周冉冉; 曹茂红

    2014-01-01

    Object ive:To investigate the changes of hyperphosphorylation of tau in the brain of diabetes mellitus model rats and to determine whether the supplementation of folic acid and vitamin B12 prevents the AD-like hyperphospho_rylation of tau in the diabetes rat brain and leaning and memory deficits, which may provide a theory reference for the clin_ical application. Methods:Diabetes mellitus rats were induced by intraperitoneal injection Streptozocin, and the treatment groups were treated with folic acid/vitamineB12. The spatial memory and learning ability was tested by the Morris water maze. Western blot was used to detect the level of some proteins such as total tau and phosphorylation of tau at some sites. Results:(1)Results of Morris water maze:both type I diabetes mellitus(T1DM) and type II diabetes mellitus(T2DM) rats had much longer escape latency (P0.05);the levels of phosphorylated tau at serine 396/404, threonine 205 and threonine 212 were increased in both T1DM group and T2DM group(P0.05);1型、2型糖尿病组大鼠额叶皮层脑组织tau蛋白在丝氨酸396/404位点、苏氨酸205位点、苏氨酸212位点的磷酸化水平较对照组及单纯药物干预组明显增高,差异有统计学意义(P<0.05),使用叶酸联合维生素B12干预后,以上位点磷酸化水平均有明显下降(P<0.05)。结论:糖尿病大鼠脑组织内tau蛋白出现阿尔茨海默病样过度磷酸化;叶酸联合维生素B12干预后可逆转病变,发挥保护脑组织作用。

  3. 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.

  4. Reversal learning and associative memory impairments in a BACHD rat model for Huntington disease.

    Directory of Open Access Journals (Sweden)

    Yah-Se K Abada

    Full Text Available Chorea and psychiatric symptoms are hallmarks of Huntington disease (HD, a neurodegenerative disorder, genetically characterized by the presence of expanded CAG repeats (>35 in the Huntingtin (HTT gene. HD patients present psychiatric symptoms prior to the onset of motor symptoms and we recently found a similar emergence of non motor and motor deficits in BACHD rats carrying the human full length mutated HTT (97 CAG-CAA repeats. We evaluated cognitive performance in reversal learning and associative memory tests in different age cohorts of BACHD rats. Male wild type (WT and transgenic (TG rats between 2 and 12 months of age were tested. Learning and strategy shifting were assessed in a cross-maze test. Associative memory was evaluated in different fear conditioning paradigms (context, delay and trace. The possible confound of a fear conditioning phenotype by altered sensitivity to a 'painful' stimulus was assessed in a flinch-jump test. In the cross maze, 6 months old TG rats showed a mild impairment in reversal learning. In the fear conditioning tasks, 4, 6 and 12 months old TG rats showed a marked reduction in contextual fear conditioning. In addition, TG rats showed impaired delay conditioning (9 months and trace fear conditioning (3 months. This phenotype was unlikely to be affected by a change in 'pain' sensitivity as WT and TG rats showed no difference in their threshold response in the flinch-jump test. Our results suggest that BACHD rats have a profound associative memory deficit and, possibly, a deficit in reversal learning as assessed in a cross maze task. The time course for the emergence of these symptoms (i.e., before the occurrence of motor symptoms in this rat model for HD appears similar to the time course in patients. These data suggest that BACHD rats may be a useful model for preclinical drug discovery.

  5. Postnatal MK-801 treatment of female rats impairs acquisition of working memory, but not reference memory in an eight-arm radial maze; no beneficial effects of enriched environment.

    Science.gov (United States)

    Nozari, Masoumeh; Mansouri, Farshad Alizadeh; Shabani, Mohammad; Nozari, Hojat; Atapour, Nafiseh

    2015-07-01

    Memory impairment has been documented in MK-801 (NMDA receptor antagonist) model of schizophrenia, but less is known on the rescue and/or differential effects of MK-801 on short- and long-term memories. We determined the effects of MK-801 treatment and/or enriched environment (EE) on acquisition of reference and working memory in developing rats. Female Wistar rats were injected with MK-801 (1 mg/kg) from postnatal days (P) 6-10. Task acquisition, working memory error (WME), and reference memory error (RME) were assessed in an eight-arm radial maze task. Behavioral performance of rats was also tested in an open field test before (P35-P40) and after (P65-P70) radial maze training to assess anxiety and locomotion. EE was applied from birth up to the end of experiments. MK-801 treatment did not influence task acquisition in the radial maze; however, by the end of training, MK-801-treated rats made significantly more WME, but not RME, compared to control rats. Ratio of WME to total error was also significantly higher in MK-801 group. EE prevented MK-801-associated behaviors in the open field but did not exert beneficial effects on working memory deficit in the radial maze task. EE per se affected behavioral performance of rats only in the open field test. Our results suggest that postnatal MK-801 treatment differentially affects working and reference memory in a young brain. Anxiety and hyperactivity associated with MK-801 are observed more severely in adulthood. Dissociation of the positive effects of EE may suggest selective modification of distinct pathways.

  6. Effects of exercise on neurogenesis in the dentate gyrus and ability of learning and memory after hippocampus lesion in adult rats

    Institute of Scientific and Technical Information of China (English)

    Lin CHEN; Shan GONG; Li-Dong SHAN; Wei-Ping XU; Yue-Jin ZHANG; Shi-Yu GUO; Tadashi Hisamitsu; Qi-Zhang YIN; Xing-Hong JIANG

    2006-01-01

    Objective To explore the effects of exercise on dentate gyrus (DG) neurogenesis and the ability of learning and memory in hippocampus-lesioned adult rats. Methods Hippocampus lesion was produced by intrahippocampal microinjection of kainic acid (KA). Bromodeoxyuridine (BrdU) was used to label dividing cells. Y maze test was used to evaluate the ability of learning and memory. Exercise was conducted in the form of forced running in a motor-driven running wheel. The speed of wheel revolution was regulated at 3 kinds of intensity: lightly running, moderately running, or heavily running. Results Hippocampus lesion could increase the number of BrdU-labeled DG cells, moderately running after lesion could further enhance the number of BrdU-labeled cells and decrease the error number (EN) in Y maze test,while neither lightly running, nor heavily running had such effects. There was a negative correlation between the number of DG BrdU-labeled cells and the EN in the Y maze test after running. Conclusion Moderate exercise could enhance the DG neurogenesis and ameliorate the ability of learning and memory in hippocampus-lesioned rats.

  7. A complex dietary supplement augments spatial learning, brain mass, and mitochondrial electron transport chain activity in aging mice.

    Science.gov (United States)

    Aksenov, Vadim; Long, Jiangang; Liu, Jiankang; Szechtman, Henry; Khanna, Parul; Matravadia, Sarthak; Rollo, C David

    2013-02-01

    We developed a complex dietary supplement designed to offset five key mechanisms of aging and tested its effectiveness in ameliorating age-related cognitive decline using a visually cued Morris water maze test. All younger mice (1 year) were unable to learn the maze even after 5 days, indicative of strong cognitive decline at older ages. In contrast, no cognitive decline was evident in older supplemented mice, even when ∼2 years old. Supplemented older mice were nearly 50% better at locating the platform than age-matched controls. Brain weights of supplemented mice were significantly greater than controls, even at younger ages. Reversal of cognitive decline in activity of complexes III and IV by supplementation was significantly associated with cognitive improvement, implicating energy supply as one possible mechanism. These results represent proof of principle that complex dietary supplements can provide powerful benefits for cognitive function and brain aging.

  8. Critical neuropsychobiological analysis of panic attack- and anticipatory anxiety-like behaviors in rodents confronted with snakes in polygonal arenas and complex labyrinths: a comparison to the elevated plus- and T-maze behavioral tests

    Directory of Open Access Journals (Sweden)

    Norberto C. Coimbra

    Full Text Available Objective: To compare prey and snake paradigms performed in complex environments to the elevated plus-maze (EPM and T-maze (ETM tests for the study of panic attack- and anticipatory anxiety-like behaviors in rodents. Methods: PubMed was reviewed in search of articles focusing on the plus maze test, EPM, and ETM, as well as on defensive behaviors displayed by threatened rodents. In addition, the authors’ research with polygonal arenas and complex labyrinth (designed by the first author for confrontation between snakes and small rodents was examined. Results: The EPM and ETM tests evoke anxiety/fear-related defensive responses that are pharmacologically validated, whereas the confrontation between rodents and snakes in polygonal arenas with or without shelters or in the complex labyrinth offers ethological conditions for studying more complex defensive behaviors and the effects of anxiolytic and panicolytic drugs. Prey vs. predator paradigms also allow discrimination between non-oriented and oriented escape behavior. Conclusions: Both EPM and ETM simple labyrinths are excellent apparatuses for the study of anxiety- and instinctive fear-related responses, respectively. The confrontation between rodents and snakes in polygonal arenas, however, offers a more ethological environment for addressing both unconditioned and conditioned fear-induced behaviors and the effects of anxiolytic and panicolytic drugs.

  9. Critical neuropsychobiological analysis of panic attack- and anticipatory anxiety-like behaviors in rodents confronted with snakes in polygonal arenas and complex labyrinths: a comparison to the elevated plus- and T-maze behavioral tests.

    Science.gov (United States)

    Coimbra, Norberto C; Paschoalin-Maurin, Tatiana; Bassi, Gabriel S; Kanashiro, Alexandre; Biagioni, Audrey F; Felippotti, Tatiana T; Elias-Filho, Daoud H; Mendes-Gomes, Joyce; Cysne-Coimbra, Jade P; Almada, Rafael C; Lobão-Soares, Bruno

    2017-01-01

    To compare prey and snake paradigms performed in complex environments to the elevated plus-maze (EPM) and T-maze (ETM) tests for the study of panic attack- and anticipatory anxiety-like behaviors in rodents. PubMed was reviewed in search of articles focusing on the plus maze test, EPM, and ETM, as well as on defensive behaviors displayed by threatened rodents. In addition, the authors' research with polygonal arenas and complex labyrinth (designed by the first author for confrontation between snakes and small rodents) was examined. The EPM and ETM tests evoke anxiety/fear-related defensive responses that are pharmacologically validated, whereas the confrontation between rodents and snakes in polygonal arenas with or without shelters or in the complex labyrinth offers ethological conditions for studying more complex defensive behaviors and the effects of anxiolytic and panicolytic drugs. Prey vs. predator paradigms also allow discrimination between non-oriented and oriented escape behavior. Both EPM and ETM simple labyrinths are excellent apparatuses for the study of anxiety- and instinctive fear-related responses, respectively. The confrontation between rodents and snakes in polygonal arenas, however, offers a more ethological environment for addressing both unconditioned and conditioned fear-induced behaviors and the effects of anxiolytic and panicolytic drugs.

  10. 76 FR 75876 - Record of Decision for the Modification of the Groton Generation Station Interconnection...

    Science.gov (United States)

    2011-12-05

    ... air permit, greenhouse gas capture and sequestration, and demand-side management. Western does not... reductions. Also, while Western did not fully evaluate an alternative addressing demand-side management due... Electric's demand-side management program. Mitigation Measures Western's proposed action would result in...

  11. TESTING OF FUEL CELLS TO RECOVER ENERGY FROM LANDFILL GAS: GROTON LANDFILL

    Science.gov (United States)

    The report summarizes the results of follow-on tests following a four-phase EPA program. The environmental impact of widespread use of this concept would be a significant reduction of global warming gas emissions (methane and carbon dioxide). The follow-on testing, conducted by N...

  12. Effects of glutamine pretreatment on learning and memory in heat-exposed rats

    Institute of Scientific and Technical Information of China (English)

    Shenghao Zhao; Lei Wang; Qin Wang; Siyi Wang; Chundi Deng; Xianfei Xie; Youe Yan; Hui Wang

    2008-01-01

    BACKGROUND: Glutamine (Gln) pretreatment can protect neural cells from injuries due to heat, ischemia, hypoxia, endotoxemia, and inflammatory factors.OBJECTIVE: To observe the effects of Gln pretreatment on learning and memory, survival time, and rectal temperature in heat-exposed rats.DESIGN, TIME AND SETTING: The present randomized grouping, neurobehavioral experiment was performed at the Laboratory of Department of Pharmacology, Basic School of Medicine, Wuhan University between March and September 2007.MATERIALS: Twenty-four healthy, Wistar rats were included in this study. SPX-160B biochemistry incubator (Shanghai Experimental Equipment Co., Ltd., China), probe electronic thermometer (11000 type, Maikepai Science and Technology Co., Ltd., China), Y-type maze box used in conjunction with MG-2 maze stimulator (Zhangjiagang Biomedical Instrument Factory, China), L-Gin (Batch No. 061218, 5 g/bottle, prepared into 10% aqueous solution, Amresco Company, USA) were used.METHODS: Twenty-four rats were randomly and evenly divided into 3 groups: heat-exposed, Gln low-lose, and Gln high-dose. Following learning and memory testing with the Y-maze, rats in the heat-exposed group were subjected to heat injury (40.5-41.5℃) in a biochemistry incubator. Rectal temperature was measured every 5 minutes. Thirty-five minutes after heat exposure, rats were removed and placed in the Y-type maze to test learning and memory again. Subsequently, the rats were returned to the same environment of thermal stimulation until they died. Rat survival time was recorded. Subsequent to learning and memory testing, rats in the Gln low-dose and high-dose groups received an i.p. injection of Gln (0.4 g/kg and 0.8 g/kg, respectively), and were exposed to heat injury. The remaining experimental procedures remained the same as for the heat-exposed group.MAIN OUTCOME MEASURES: Rat learning and memory, rectal temperature, and survival time in heat exposure environment.RESULTS: (1) In the Y-maze

  13. Learning to aid learning.

    Science.gov (United States)

    Richards, Jacqui

    2016-01-01

    The National Health Service (NHS) is one of the largest employers in the world and, with 1.3 million staff, the biggest employer in Europe. With over three hundred different careers on offer (NHS 2015), the acquisition of skills and qualifications, through academic and clinical training, is an integral part of day-to-day life in the health service. As such, mentoring has become a significant feature in the preparation of healthcare professionals, to support students and ensure learning needs and experiences are appropriate to competency. This article examines the mentor's role, in relation to a teaching innovation designed to address students' identified learning needs to meet the requirements of the multi-professional learning and assessment in practice course NM6156. The effectiveness of the aids to learning will be assessed through an online quiz, and its usefulness will be analysed with reference to educational theories of learning and development.

  14. Neurotoxicity induced by alkyl nitrites: Impairment in learning/memory and motor coordination.

    Science.gov (United States)

    Cha, Hye Jin; Kim, Yun Ji; Jeon, Seo Young; Kim, Young-Hoon; Shin, Jisoon; Yun, Jaesuk; Han, Kyoungmoon; Park, Hye-Kyung; Kim, Hyung Soo

    2016-04-21

    Although alkyl nitrites are used as recreational drugs, there is only little research data regarding their effects on the central nervous system including their neurotoxicity. This study investigated the neurotoxicity of three representative alkyl nitrites (isobutyl nitrite, isoamyl nitrite, and butyl nitrite), and whether it affected learning/memory function and motor coordination in rodents. Morris water maze test was performed in mice after administrating the mice with varying doses of the substances in two different injection schedules of memory acquisition and memory retention. A rota-rod test was then performed in rats. All tested alkyl nitrites lowered the rodents' capacity for learning and memory, as assessed by both the acquisition and retention tests. The results of the rota-rod test showed that isobutyl nitrite in particular impaired motor coordination in chronically treated rats. The mice chronically injected with isoamyl nitrite also showed impaired function, while butyl nitrite had no significant effect. The results of the water maze test suggest that alkyl nitrites may impair learning and memory. Additionally, isoamyl nitrite affected the rodents' motor coordination ability. Collectively, our findings suggest that alkyl nitrites may induce neurotoxicity, especially on the aspect of learning and memory function.

  15. Effect of melatonin and vitamin E on diabetes-induced learning and memory impairment in rats.

    Science.gov (United States)

    Tuzcu, Mehmet; Baydas, Giyasettin

    2006-05-10

    Previous studies indicate that diabetes mellitus might be accompanied by a certain erosion of brain function such as cognitive impairment. The aim of this study was to examine and compare the effects of melatonin and vitamin E on cognitive functions in diabetic rats. Diabetes was induced in male albino rats via intraperitoneal streptozotocin injection. Learning and memory behaviors were investigated using a spatial version of the Morris water maze test. The levels of lipid peroxidation and glutathione were detected in hippocampus and frontal cortex. The diabetic rats developed significant impairment in learning and memory behaviors as indicated by the deficits in water maze tests as compared to control rats. Furthermore, lipid peroxidation levels increased and glutathione concentration decreased in diabetic rats. Treatment with melatonin and vitamin E significantly ameliorated learning and memory performance. Furthermore, both antioxidants reversed lipid peroxidation and glutathione levels toward their control values. These results suggest that oxidative stress may contribute to learning and memory deficits in diabetes and further suggest that antioxidant melatonin and vitamin E can improve cognitive impairment in streptozotocin-induced diabetes.

  16. Sex differences on the competitive place task in the water maze: The influence of peripheral pool time on spatial navigation performance in rats.

    Science.gov (United States)

    Devan, Bryan D; Tobin, Elizabeth L; Dunn, Emily N; Magalis, Christopher

    2016-11-01

    This study investigated sex differences on the competitive place version of the Morris water maze task to determine whether potential strategy differences would emerge during any phase of the study but in particular on the competitive place phase. Previous findings indicate that this version of the task is highly sensitive to measures that disrupt NMDA-dependent synaptic plasticity within the hippocampus during memory consolidation (McDonald et al., 2005). The present findings revealed significant sex differences during all phases of the study, including Phase I with standard place training to located a hidden platform/goal, Phase II mass training to a new place with the platform/goal relocated to the diagonally opposite quadrant and Phase III, competitive place probe test with the platform removed to measure spatial behaviour directed at either location. The findings showed no sex difference in escape latency and other standard performance measures during the first two phases, initial place acquisition and mass training to a new location. A very subtle male advantage in visiting both Old and New place locations during the third phase place competition test was observed, however, in the time spent swimming in the periphery of the pool, the pool wall (Zone C - outer third radial distance) was increased for females during all phases of the study, suggesting a general effect may have influenced place location search behaviour of the females. Increased peripheral pool time may represent a female preference for approaching the wall, a local cue. Alternatively, the possibility that increased peripheral swimming/thigmotaxis may represent hormonal influences interacting with strategic preferences were discussed, though no definitive conclusions about sex differences in cognitive-spatial performance or memory consolidation were inferred from the present findings. The findings suggest that mixed results reported in the literature by others may be due in part to an

  17. Rats with differential self-grooming expression in the elevated plus-maze do not differ in anxiety-related behaviors.

    Science.gov (United States)

    Reimer, Adriano Edgar; de Oliveira, Amanda Ribeiro; Diniz, Juliana Belo; Hoexter, Marcelo Queiroz; Chiavegatto, Silvana; Brandão, Marcus Lira

    2015-10-01

    Individual differences are important biological predictors for reactivity to stressful stimulation. The extent to which trait differences underlie animal's reactions to conditioned and unconditioned fear stimuli, for example, is still to be clarified. Although grooming behavior has been associated with some aspects of the obsessive-compulsive disorder in humans, its relation with other anxiety disorders is still unknown. Given that grooming behavior could be a component of the whole spectrum of these disorders, in the present study we allocated male Wistar rats in low, intermediate and high self-grooming groups according to the duration of such behavior in the elevated plus-maze (EPM). These groups were then evaluated in unconditioned fear tests, such as the EPM and the open-field, and in conditioned fear tests, such as fear-potentiated startle and fear extinction retention. Additionally, we studied the expression of unconditioned behaviors in marble burying test and the sensorimotor gate function with prepulse inhibition test. Neurochemicals and neuroendocrine parameters were also evaluated, with the quantification of basal corticosterone in the plasma, and dopamine, serotonin and their metabolites in brain structures involved with fear processing. In general, rats classified according to grooming expression showed similar performance in all behavioral tests. Accordingly, corticosterone and monoamine concentrations were similar among groups. Thus, despite grooming expression elicited by different approaches--especially pharmacological ones--has been related with some aspects of anxiety disorders, rats with different expression of spontaneous self-grooming in the EPM do not differ in anxiety-like behaviors nor in neurochemical and neuroendocrine parameters generally associated with anxiety disorders.

  18. A working memory "theory of relativity": elasticity in temporal, spatial, and modality dimensions conserves item capacity in radial maze, verbal tasks, and other cognition.

    Science.gov (United States)

    Glassman, R B

    1999-03-15

    It is remarkable that working memory (WM) capacity for numbers of items remains modest, at approximately 7+/-2 (the so-called "magical number"), across a wide variety of kinds of material. Indeed, consideration of radial maze studies together with more traditional memory research shows that WM capacity remains fairly constant whether the items are verbal or visuospatial, and that this same capacity is true of other species as of humans. In contrast to their limited numerousness, WM items are extremely flexible in ways that are here brought under the heading of "dimensionality." Therefore, the physical items represented in WM, can vary widely in any quantitative characteristic and in the temporal pace at which they are encountered. Combinatorial considerations suggest that WM numerousness results from evolution of a middle ground between a sterile parsimony and an overwhelming excess, for organizing neurocognitive associations. Such natural selection seems likely to have worked opportunistically to yield diverse characteristics of neuronal tissue, from subcellular components to properties of ensembles, which converge on the required cognitive properties of WM. Priming and implicit memory may play supporting roles with WM. These intermediate-term memory phenomena allow certain kinds of background information to be accumulated at higher volume than seems possible from the textbook, "modal model" of memory. By expediting attentional focus on subsets of information already in long-term memory, priming may help WM chunks to emerge in limited number as appropriately scaled "figures" from the primed "ground." The larger neuronal dynamic patterns that embody these cognitive phenomena must regulate their microscopic component systems, automatically selecting those having parameters of temporal persistence, rhythm, and connectivity patterns that are pertinent to the current task. Relevant neural phenomena may include "Hebbian" associativity and persistence of firing patterns

  19. The effect of modafinil on the rat dopamine transporter and dopamine receptors D1-D3 paralleling cognitive enhancement in the radial arm maze

    Directory of Open Access Journals (Sweden)

    Yasemin eKarabacak

    2015-08-01

    Full Text Available A series of drugs have been reported to increase memory performance modulating the dopaminergic system and herein modafinil was tested for its working memory (WM enhancing properties. Reuptake inhibition of dopamine, serotonin (SERT and norepinephrine (NET by modafinil was tested. 60 male Sprague Dawley rats were divided into six groups (modafinil-treated 1-5-10 mg/kg body weight, trained and untrained and vehicle treated trained and untrained rats; daily injected intraperitoneally for a period of 10 days and tested in a radial arm maze (RAM, a paradigm for testing spatial WM. Hippocampi were taken six hours following the last day of training and complexes containing the unphosphorylated or phosphorylated dopamine transporter (DAT-CC and pDAT-CC and complexes containing the D1-3 dopamine receptor subunits (D1-D3-CC were determined. Modafinil was binding to the DAT but insignificantly to SERT or NET and dopamine reuptake was blocked specifically (IC50=11.11; SERT 1547; NET 182. From day 8 (day 9 for 1 mg/kg body weight modafinil was decreasing WM errors in the RAM significantly and remarkably at all doses tested as compared to the vehicle controls. WMEs were linked to the D2R-CC and the pDAT-CC. pDAT and D1-D3-CC levels were modulated significantly and modafinil was shown to enhance spatial WM in the rat in a well-documented paradigm at all the three doses and dopamine reuptake inhibition with subsequent modulation of D1-3-CC is proposed as a possible mechanism of action.

  20. The effect of modafinil on the rat dopamine transporter and dopamine receptors D1–D3 paralleling cognitive enhancement in the radial arm maze

    Science.gov (United States)

    Karabacak, Yasemin; Sase, Sunetra; Aher, Yogesh D.; Sase, Ajinkya; Saroja, Sivaprakasam R.; Cicvaric, Ana; Höger, Harald; Berger, Michael; Bakulev, Vasiliy; Sitte, Harald H.; Leban, Johann; Monje, Francisco J.; Lubec, Gert

    2015-01-01

    A series of drugs have been reported to increase memory performance modulating the dopaminergic system and herein modafinil was tested for its working memory (WM) enhancing properties. Reuptake inhibition of dopamine, serotonin (SERT) and norepinephrine (NET) by modafinil was tested. Sixty male Sprague–Dawley rats were divided into six groups (modafinil-treated 1–5–10 mg/kg body weight, trained and untrained and vehicle treated trained and untrained rats; daily injected intraperitoneally for a period of 10 days) and tested in a radial arm maze (RAM), a paradigm for testing spatial WM. Hippocampi were taken 6 h following the last day of training and complexes containing the unphosphorylated or phosphorylated dopamine transporter (DAT-CC and pDAT-CC) and complexes containing the D1–3 dopamine receptor subunits (D1–D3-CC) were determined. Modafinil was binding to the DAT but insignificantly to SERT or NET and dopamine reuptake was blocked specifically (IC50 = 11.11 μM; SERT 1547 μM; NET 182 μM). From day 8 (day 9 for 1 mg/kg body weight) modafinil was decreasing WM errors (WMEs) in the RAM significantly and remarkably at all doses tested as compared to the vehicle controls. WMEs were linked to the D2R-CC and the pDAT-CC. pDAT and D1–D3-CC levels were modulated significantly and modafinil was shown to enhance spatial WM in the rat in a well-documented paradigm at all the three doses and dopamine reuptake inhibition with subsequent modulation of D1–3-CC is proposed as a possible mechanism of action. PMID:26347626

  1. Male rats with same sex preference show high experimental anxiety and lack of anxiogenic-like effect of fluoxetine in the plus maze test.

    Science.gov (United States)

    García-Cárdenas, Nallely; Olvera-Hernández, Sandra; Gómez-Quintanar, Blanca Nelly; Fernández-Guasti, Alonso

    2015-08-01

    Homosexual men show a 2-4 higher risk to suffer anxiety in comparison with heterosexuals. It is unknown if biological factors collaborate to increase such incidence. Fluoxetine produces differential brain activation in homosexuals as compared with heterosexuals, suggesting that it may produce a divergent behavioral effect dependant on sex-preference. The first aim was to evaluate experimental anxiety in male rats that show same-sex preference in the elevated plus maze (EPM). The second goal explored the putative differential effect of fluoxetine (10mg/kg) in male rats with female and same-sex preference in the EPM. To induce same-sex preference males were prenatally treated with letrozole (0.56μg/kg, 10-20 gestation days), while controls were males prenatally treated with letrozole that retain female-preference or which mothers received oil. In both groups we found animals with male preference, but the proportion was higher in males that prenatally received letrozole (10 vs. 27%). Males with same-sex preference spent less time and showed lower number of entries to the open arms of the EPM than males that prefer females, regardless of the prenatal treatment. In males with female preference, fluoxetine reduced the time spent and number of entries to the open arms that was absent in males with same-sex preference. These data suggest that biological factors contribute to the high levels of anxiety in subjects with same-sex preference and that fluoxetine in men may produce a divergent action depending on sexual orientation.

  2. Influence of bupropion and calcium channel antagonists on the nicotine-induced memory-related response of mice in the elevated plus maze.

    Science.gov (United States)

    Biała, Grazyna; Kruk, Marta

    2009-01-01

    In this study, we investigated the effects of acute administration of nicotine on memory-related behavior in mice using the elevated plus maze test. In this test, the time necessary for mice to move from the open arm to the enclosed arm (i.e., transfer latency) was used as an index of memory. Our results revealed that nicotine (0.035 and 0.175 mg/kg, base, sc) shortened the transfer latency relative to the saline-treated group. Moreover, we investigated the effects of bupropion (10, 20 and 40 mg/kg, ip) and L-type voltage-dependent calcium channel antagonists (nimodipine, flunarizine, verapamil, diltiazem - 5, 10 and 20 mg/kg, ip) on memory-related behavior. At all tested doses, bupropion, did not significantly affect transfer latency. However, flunarizine and verapamil (both at 10 mg/kg) resulted in a slight decrease in transfer latency, whereas nimodipine (10 mg/kg) increased transfer latency. Interestingly, both bupropion (20 mg/kg) and calcium channel blockers (5 mg/kg) attenuated the improvement of memory induced by nicotine. Our findings indicate that the cholinergic nicotinic system may play an important role in memory consolidation, and that neural calcium-dependent mechanisms can be involved in the modulation of memory-related responses induced by nicotine. The results of these studies have revealed neuronal mechanisms that are important for nicotinic modulation of cognition and will be useful for the treatments of human disorders in which cholinergic pathways have been implicated, such as psychiatric disorders and addiction.

  3. Role of TRPV1 channels of the dorsal periaqueductal gray in the modulation of nociception and open elevated plus maze-induced antinociception in mice.

    Science.gov (United States)

    Mascarenhas, Diego Cardozo; Gomes, Karina Santos; Nunes-de-Souza, Ricardo Luiz

    2015-10-01

    Recent findings have identified the presence of transient receptor potential vanilloid-1 (TRPV1) channels within the dorsal portion of the periaqueductal gray (dPAG), suggesting their involvement in the control of pain and environmentally-induced antinociception. Environmentally, antinociception may be achieved through the use of an open elevated plus maze (oEPM, an EPM with 4 open arms), a highly aversive environmental situation. Here, we investigated the role of these TRPV1 channels within the dPAG in the modulation of a tonic pain and in the oEPM-induced antinociception. Male Swiss mice, under the nociceptive effect of 2.5% formalin injected into the right hind paw, received intra-dPAG injections of the TRPV1 agonist (capsaicin: 0, 0.01, 0.1 or 1.0 nmol/0.2 μL; Experiment 1) or antagonist (capsazepine: 0, 10 or 30 nmol/0.2 μL; Experiment 2) or combined injections of capsazepine (30 nmol) and capsaicin (1.0 nmol) (Experiment 3) and the time spent licking the formalin-injected paw was recorded. In Experiment 4, mice received intra-dPAG capsazepine (0 or 30 nmol) and were exposed to the oEPM or to a control situation, an enclosed EPM (eEPM; an EPM with 4 enclosed arms). Results showed that while capsaicin (1 nmol) decreased the time spent licking the formalin-injected paw, capsazepine did not change nociceptive response. Capsazepine (30 nmol) blocked pain inhibition induced by capsaicin and mildly attenuated the oEPM-induced antinociception. Our results revealed an important role of TRPV1 channels within the dPAG in the modulation of pain and in the phenomenon known as fear-induced antinociception in mice.

  4. Anxiolytic effects of repeated treatment with an essential oil from Lippia alba and (R-(--carvone in the elevated T-maze

    Directory of Open Access Journals (Sweden)

    V.Y. Hatano

    2012-03-01

    Full Text Available Lippia alba (Mill. N.E. Brown (Verbenaceae is widely used in different regions of Central and South America as a tranquilizer. The plant’s anxiolytic properties, however, merit investigation. The present study evaluated the effects of repeated daily (14 days intraperitoneal (ip treatment with an essential oil (EO from a chemotype of L. alba (LA, chemotype II, 12.5 and 25 mg/kg; N = 6-8 and (R-(--carvone (25 mg/kg; N = 8-12, the main constituent of this chemotype, on male Wistar rats (weighing 250 g at the beginning of the experiments submitted to the elevated T-maze (ETM. The ETM allows the measurement of two defensive responses: inhibitory avoidance and one-way escape. In terms of psychopathology, these responses have been related to generalized anxiety and panic disorder, respectively. Treatment with the EO impaired ETM avoidance latencies, without altering escape, in a way similar to the reference drug diazepam (P < 0.05 (avoidance 2: control = 84.6 ± 35.2; EO 12.5 mg/kg = 11.8 ± 3.8; EO 25 mg/kg = 14.6 ± 2.7; diazepam = 7 ± 2.1. (R-(--carvone also significantly altered this same response (P < 0.05; avoidance 1: control = 91.9 ± 31.5; carvone = 11.6 ± 1.8; diazepam = 8.1 ± 3.3. These results were not due to motor changes since no significant effects were detected in an open field. These observations suggest that LA exerts anxiolytic-like effects on a specific subset of defensive behaviors that have been implicated in generalized anxiety disorder, and suggest that carvone is one of the constituents of LA responsible for its action as a tranquilizer.

  5. Anxiolytic effects of repeated treatment with an essential oil from Lippia alba and (R)-(-)-carvone in the elevated T-maze

    Energy Technology Data Exchange (ETDEWEB)

    Hatano, V.Y.; Torricelli, A.S. [Departamento de Biociências, Universidade Federal de São Paulo, Santos, SP (Brazil); Giassi, A.C.C. [Cellular and Molecular Medicine, University of Ottawa, Ottawa (Canada); Coslope, L.A. [Parque Nacional da Chapada Diamantina, Chapada Diamantina, BA (Brazil); Viana, M.B. [Departamento de Biociências, Universidade Federal de São Paulo, Santos, SP (Brazil)

    2012-02-27

    Lippia alba (Mill.) N.E. Brown (Verbenaceae) is widely used in different regions of Central and South America as a tranquilizer. The plant's anxiolytic properties, however, merit investigation. The present study evaluated the effects of repeated daily (14 days) intraperitoneal (ip) treatment with an essential oil (EO) from a chemotype of L. alba (LA, chemotype II, 12.5 and 25 mg/kg; N = 6-8) and (R)-(-)-carvone (25 mg/kg; N = 8-12), the main constituent of this chemotype, on male Wistar rats (weighing 250 g at the beginning of the experiments) submitted to the elevated T-maze (ETM). The ETM allows the measurement of two defensive responses: inhibitory avoidance and one-way escape. In terms of psychopathology, these responses have been related to generalized anxiety and panic disorder, respectively. Treatment with the EO impaired ETM avoidance latencies, without altering escape, in a way similar to the reference drug diazepam (P < 0.05) (avoidance 2: control = 84.6 ± 35.2; EO 12.5 mg/kg = 11.8 ± 3.8; EO 25 mg/kg = 14.6 ± 2.7; diazepam = 7 ± 2.1). (R)-(-)-carvone also significantly altered this same response (P < 0.05; avoidance 1: control = 91.9 ± 31.5; carvone = 11.6 ± 1.8; diazepam = 8.1 ± 3.3). These results were not due to motor changes since no significant effects were detected in an open field. These observations suggest that LA exerts anxiolytic-like effects on a specific subset of defensive behaviors that have been implicated in generalized anxiety disorder, and suggest that carvone is one of the constituents of LA responsible for its action as a tranquilizer.

  6. Anxiogenic effects of activation of NK-1 receptors of the dorsal periaqueductal gray as assessed by the elevated plus-maze, ultrasound vocalizations and tail-flick tests.

    Science.gov (United States)

    Bassi, Gabriel S; Nobre, Manoel J; de Araújo, João E; Brandão, Marcus L

    2007-12-01

    Ultrasound vocalizations (USVs) known as 22kHz are usual components of the defensive responses of rats exposed to threatening conditions. The amount of emission of 22kHz USVs depends on the intensity of the aversive stimuli. While moderate fear causes an anxiolytic-sensitive enhancement of the defensive responses, high fear tended to reduce the defensive performance of the animals to aversive stimuli. The dorsal periaqueductal gray (dPAG) is an important vocal center and a crucial structure for the expression of defensive responses. Substance P (SP) is involved in the modulation of the defensive response at this midbrain level, but the type of neurokinin receptors involved in this action is not completely understood. In this study we examined whether local injections of the selective NK-1 agonist SAR-MET-SP (10-100 pmol/0.2microL) into the dPAG (i) cause anxiogenic effects in the elevated plus-maze (EPM) (Exp. I), (ii) influence the novelty-induced 22kHz USVs recorded within the frequency range of 20-26kHz (Exp. II) and (iii) change the nociceptive reactivity to heat applied to the rat's tail (Exp III). The data obtained showed that SAR-MET-SP elicited significant "anxiety-like" behaviors, as revealed by the decrease in the number of entries into and time spent onto the open arms of the EPM. These anxiogenic effects were accompanied with antinociception and disruption of the novelty-induced increase in the number and duration of 22kHz USVs. These findings are in agreement with the notion that NK-1 receptors of the dPAG may be an important neurochemical target for new selective drugs aimed at the control of pathological anxiety states.

  7. Calcium channel antagonists suppress cross-tolerance to the anxiogenic effects of D-amphetamine and nicotine in the mouse elevated plus maze test.

    Science.gov (United States)

    Biala, Grazyna; Kruk, Marta

    2008-01-01

    The purpose of the current experiments was to examine the anxiety-related effects of repeated amphetamine and nicotine administration using the mouse elevated plus maze (EPM). d-amphetamine was administered daily for 8 days (2 mg/kg, i.p.). On the 9th day, mice were challenged with amphetamine (2 mg/kg, i.p.) or nicotine (0.1 mg/kg, s.c.), and were tested 30 min after this last injection. Additionally, a distinct group of mice was pretreated with nicotine (0.1 mg/kg, s.c., 6 days). These mice were subjected to nicotine (0.1 mg/kg, s.c.) or amphetamine (2 mg/kg, i.p.) challenge on the seventh day to see if full crossover effects developed after the pretreatment of both psychostimulant drugs. Moreover, the L-type voltage-dependent calcium channel antagonists nimodipine (5 and 10 mg/kg, i.p.), flunarizine (5 and 10 mg/kg, i.p.), verapamil (5 and 10 mg/kg, i.p.) and diltiazem (5 and 10 mg/kg, i.p.) were injected prior to each injection of chronic d-amphetamine or nicotine. We observed cross-tolerance to the anxiogenic effects of d-amphetamine and nicotine that was blunted by a pretreatment with calcium channel blockers. Overall our findings imply that similar neural calcium-dependent mechanisms are involved in the anxiety-related responses to chronic amphetamine and nicotine injections. As anxiety seems to be an important factor for the development of psychostimulant dependence, the L-type VDCC antagonists can offer an interesting approach for the pharmacotherapy of addiction, including amphetamine and/or nicotine dependence.

  8. Modulation of anxiety in rats evaluated in the elevated T-maze: evidence of the relationship between substance P and diazepam.

    Science.gov (United States)

    Duzzioni, Marcelo; Calixto, Ana V; Duarte, Filipe S; De Lima, Thereza C M

    2008-02-11

    This study aimed to investigate the relationship between substance P (SP) and diazepam (DZP) in the modulation of anxiety and memory in rats as evaluated in the elevated T-maze (ETM). For this purpose, in the first experiment, rats were intraperitoneally (i.p.) pretreated with saline or DZP (1mg/kg) and 25min later they were intracerebroventricularly (i.c.v.) injected with PBS or SP (10 pmol). In the second experiment, rats were i.p. pretreated with saline or DZP (1mg/kg) and 25 min later were i.c.v. injected with FK888 (100 pmol, a NK1 antagonist). After 1 min, animals were i.c.v. injected with vehicle (PBS+ethanol 10%) or SP (10 pmol). Our results show that DZP significantly decreased the latency to leave the enclosed arm of the ETM in the test and re-test session, indicating an anxiolytic and an amnesic effect, respectively. Although the central administration of SP did not significantly alter 'per se' the latency to leave the enclosed arm of the ETM in the test and re-test sessions, there was a trend to increase this parameter in the test session (indicating an anxiogenic-like effect). Furthermore, SP was able to reverse, via NK1 receptors, the effect produced by DZP during the test session. Moreover, none of the treatments interfered in the one-way escape behavior recorded in the test or re-test session in the ETM. In conclusion, our results strengthen and extend previous experimental data showing an interaction between the tachykinergic and benzodiazepine-GABA systems in the modulation of anxiety.

  9. H₁ but not H₂ histamine antagonist receptors mediate anxiety-related behaviors and emotional memory deficit in mice subjected to elevated plus-maze testing.

    Science.gov (United States)

    Serafim, K R; Kishi, M S; Canto-de-Souza, A; Mattioli, R

    2013-05-01

    This study investigated the role of H₁ and H₂ receptors in anxiety and the retrieval of emotional memory using a Trial 1/Trial 2 (T1/T2) protocol in an elevated plus-maze (EPM). Tests were performed on 2 consecutive days, designated T1 and T2. Before T1, the mice received intraperitoneal injections of saline (SAL), 20 mg/kg zolantidine (ZOL, an H2 receptor antagonist), or 8.0 or 16 mg/kg chlorpheniramine (CPA, an H1 receptor antagonist). After 40 min, they were subjected to the EPM test. In T2 (24 h later), each group was subdivided into two additional groups, and the animals from each group were re-injected with SAL or one of the drugs. In T1, the Student t-test showed no difference between the SAL and ZOL or 8 mg/kg CPA groups with respect to the percentages of open arm entries (%OAE) and open arm time (%OAT). However, administration of CPA at the highest dose of 16 mg/kg decreased %OAE and %OAT, but not locomotor activity, indicating anxiogenic-like behavior. Emotional memory, as revealed by a reduction in open arm exploration between the two trials, was observed in all experimental groups, indicating that ZOL and 8 mg/kg CPA did not affect emotional memory, whereas CPA at the highest dose affected acquisition and consolidation, but not retrieval of memory. Taken together, these results suggest that H₁ receptor, but not H₂, is implicated in anxiety-like behavior and in emotional memory acquisition and consolidation deficits in mice subjected to EPM testing.

  10. Anxiolytic effects of repeated treatment with an essential oil from Lippia alba and (R)-(-)-carvone in the elevated T-maze.

    Science.gov (United States)

    Hatano, V Y; Torricelli, A S; Giassi, A C C; Coslope, L A; Viana, M B

    2012-03-01

    Lippia alba (Mill.) N.E. Brown (Verbenaceae) is widely used in different regions of Central and South America as a tranquilizer. The plant's anxiolytic properties, however, merit investigation. The present study evaluated the effects of repeated daily (14 days) intraperitoneal (ip) treatment with an essential oil (EO) from a chemotype of L. alba (LA, chemotype II, 12.5 and 25 mg/kg; N = 6-8) and (R)-(-)-carvone (25 mg/kg; N = 8-12), the main constituent of this chemotype, on male Wistar rats (weighing 250 g at the beginning of the experiments) submitted to the elevated T-maze (ETM). The ETM allows the measurement of two defensive responses: inhibitory avoidance and one-way escape. In terms of psychopathology, these responses have been related to generalized anxiety and panic disorder, respectively. Treatment with the EO impaired ETM avoidance latencies, without altering escape, in a way similar to the reference drug diazepam (P < 0.05) (avoidance 2: control = 84.6 ± 35.2; EO 12.5 mg/kg = 11.8 ± 3.8; EO 25 mg/kg = 14.6 ± 2.7; diazepam = 7 ± 2.1). (R)-(-)-carvone also significantly altered this same response (P < 0.05; avoidance 1: control = 91.9 ± 31.5; carvone = 11.6 ± 1.8; diazepam = 8.1 ± 3.3). These results were not due to motor changes since no significant effects were detected in an open field. These observations suggest that LA exerts anxiolytic-like effects on a specific subset of defensive behaviors that have been implicated in generalized anxiety disorder, and suggest that carvone is one of the constituents of LA responsible for its action as a tranquilizer.

  11. A neural learning classifier system with self-adaptive constructivism for mobile robot control.

    Science.gov (United States)

    Hurst, Jacob; Bull, Larry

    2006-01-01

    For artificial entities to achieve true autonomy and display complex lifelike behavior, they will need to exploit appropriate adaptable learning algorithms. In this context adaptability implies flexibility guided by the environment at any given time and an open-ended ability to learn appropriate behaviors. This article examines the use of constructivism-inspired mechanisms within a neural learning classifier system architecture that exploits parameter self-adaptation as an approach to realize such behavior. The system uses a rule structure in which each rule is represented by an artificial neural network. It is shown that appropriate internal rule complexity emerges during learning at a rate controlled by the learner and that the structure indicates underlying features of the task. Results are presented in simulated mazes before moving to a mobile robot platform.

  12. Effect of behavior training on learning and memory of young rats with fetal growth restriction

    Institute of Scientific and Technical Information of China (English)

    Li Xuelan; Gou Wenli; Huang Pu; Li Chunfang; Sun Yunping

    2008-01-01

    Objective: To investigate the effect of behavior training on the learning and memory of young rats with fetal growth restriction (FGR). Methods: The model of FGR was established by passive smoking method to pregnant rats.The new-born rats were divided into FGR group and normal group, and then randomly subdivided into trained and untrained group respectively. Morris water maze behavior training was performed on postnatal months 2 and 4, then learning and memory abilities of young rats were measured by dark-avoidance testing and step-down testing. Results: In the dark-avoidance and step-down testing, the young rats' performance of FGR group was worse than that of control group, and the trained group was better than the untrained group significantly. Conclusion: FGR young rats have descended learning and memory abilities. Behavior training could improve the young rats' learning and memory abilities, especially for the FGR young rats.

  13. Goal-oriented searching mediated by ventral hippocampus early in trial-and-error learning.

    Science.gov (United States)

    Ruediger, Sarah; Spirig, Dominique; Donato, Flavio; Caroni, Pico

    2012-11-01

    Most behavioral learning in biology is trial and error, but how these learning processes are influenced by individual brain systems is poorly understood. Here we show that ventral-to-dorsal hippocampal subdivisions have specific and sequential functions in trial-and-error maze navigation, with ventral hippocampus (vH) mediating early task-specific goal-oriented searching. Although performance and strategy deployment progressed continuously at the population level, individual mice showed discrete learning phases, each characterized by particular search habits. Transitions in learning phases reflected feedforward inhibitory connectivity (FFI) growth occurring sequentially in ventral, then intermediate, then dorsal hippocampal subdivisions. FFI growth at vH occurred abruptly upon behavioral learning of goal-task relationships. vH lesions or the absence of vH FFI growth delayed early learning and disrupted performance consistency. Intermediate hippocampus lesions impaired intermediate place learning, whereas dorsal hippocampus lesions specifically disrupted late spatial learning. Trial-and-error navigational learning processes in naive mice thus involve a stereotype sequence of increasingly precise subtasks learned through distinct hippocampal subdivisions. Because of its unique connectivity, vH may relate specific goals to internal states in learning under healthy and pathological conditions.

  14. Psoriasis & Comorbidities: Unraveling the Maze

    NARCIS (Netherlands)

    E.A. Dowlatshahi (Emmilia)

    2014-01-01

    markdownabstract__Abstract__ In this thesis we used a multifaceted approach to analyzing depression in psoriasis, by investigating Health Related Quality of Life (HRQoL), depressive symptoms, clinical depression and antidepressant use, using various data sources and statistical methods. These inclu

  15. Psoriasis & Comorbidities: Unraveling the Maze

    NARCIS (Netherlands)

    E.A. Dowlatshahi (Emmilia)

    2014-01-01

    markdownabstract__Abstract__ In this thesis we used a multifaceted approach to analyzing depression in psoriasis, by investigating Health Related Quality of Life (HRQoL), depressive symptoms, clinical depression and antidepressant use, using various data sources and statistical methods. These

  16. Low-dose sevoflurane promotes hippocampal neurogenesis and facilitates the development of dentate gyrus-dependent learning in neonatal rats.

    Science.gov (United States)

    Chen, Chong; Shen, Feng-Yan; Zhao, Xuan; Zhou, Tao; Xu, Dao-Jie; Wang, Zhi-Ru; Wang, Ying-Wei

    2015-01-01

    Huge body of evidences demonstrated that volatile anesthetics affect the hippocampal neurogenesis and neurocognitive functions, and most of them showed impairment at anesthetic dose. Here, we investigated the effect of low dose (1.8%) sevoflurane on hippocampal neurogenesis and dentate gyrus-dependent learning. Neonatal rats at postnatal day 4 to 6 (P4-6) were treated with 1.8% sevoflurane for 6 hours. Neurogenesis was quantified by bromodeoxyuridine labeling and electrophysiology recording. Four and seven weeks after treatment, the Morris water maze and contextual-fear discrimination learning tests were performed to determine the influence on spatial learning and pattern separation. A 6-hour treatment with 1.8% sevoflurane promoted hippocampal neurogenesis and increased the survival of newborn cells and the proportion of immature granular cells in the dentate gyrus of neonatal rats. Sevoflurane-treated rats performed better during the training days of the Morris water maze test and in contextual-fear discrimination learning test. These results suggest that a subanesthetic dose of sevoflurane promotes hippocampal neurogenesis in neonatal rats and facilitates their performance in dentate gyrus-dependent learning tasks.

  17. Potential Association of Lead Exposure During Early Development of Mice With Alteration of Hippocampus Nitric Oxide Levels and Learning Memory

    Institute of Scientific and Technical Information of China (English)

    LI SUN; ZHENG-YAN ZHAO; JIAN HU; XIE-LAI ZHOU

    2005-01-01

    Objective Chronic lead (Pb) exposure during development is known to produce learning deficits. Nitric oxide participates in the synaptic mechanisms involved in certain forms of learning and memory. This study was designed to clarify whether Pb-induced impairment in learning and memory was associated with the changes of nitric oxide levels in mice brains.Methods Sixty Balb/c mice aged 10 days were chosen. A model of lead exposure was established by drinking 0.025%, 0.05%,0.075% lead acetate, respectively for 8 weeks. The controls were orally given distilled water. The ability to learn and memorize was examined by open field test, T-water maze test. In parallel with the behavioral data, NO level of hippocampus tissue was detected by biochemical assay. Results Compared with control groups, (1) the weight of 0.075% group was significantly reduced (P<0.05); (2) The number of times in mice attaining the required standards in T-water maze test was lower in 0.075%group (P<0.01). No significant difference was found between experimental and control groups in open field test (P>0.05); (3)NO level of mouse hippocampus tissue was decreased in 0.075% group (P<0.01). Conclusions The findings suggest that decreased hippocampus NO level may contribute to the Pb-induced deficits in learning and memory processes.

  18. Long-term ω-3 fatty acid supplementation induces anti-stress effects and improves learning in rats.

    Science.gov (United States)

    Pérez, Miguel Á; Terreros, Gonzalo; Dagnino-Subiabre, Alexies

    2013-06-14

    Chronic stress leads to secretion of the adrenal steroid hormone corticosterone, inducing hippocampal atrophy and dendritic hypertrophy in the rat amygdala. Both alterations have been correlated with memory impairment and increased anxiety. Supplementation with ω-3 fatty acids improves memory and learning in rats. The aim of this study was to evaluate the effects of ω-3 supplementation on learning and major biological and behavioral stress markers. Male Sprague-Dawley rats were randomly assigned to three experimental groups: 1) Control, 2) Vehicle, animals supplemented with water, and 3) ω-3, rats supplemented with ω-3 (100 mg of DHA+25 mg of EPA). Each experimental group was divided into two subgroups: one of which was not subjected to stress while the other was subjected to a restraint stress paradigm. Afterwards, learning was analyzed by avoidance conditioning. As well, plasma corticosterone levels and anxiety were evaluated as stress markers, respectively by ELISA and the plus-maze test. Restraint stress impaired learning and increased both corticosterone levels and the number of entries into the open-arm (elevated plus-maze). These alterations were prevented by ω-3 supplementation. Thus, our results demonstrate that ω-3 supplementation had two beneficial effects on the stressed rats, a strong anti-stress effect and improved learning.

  19. The effect of Nigella sativa on learning and memory in male diabetic rats

    Directory of Open Access Journals (Sweden)

    Mohammad reza Jalali nodoushan

    2009-01-01

    Full Text Available   Abstract   Introduction: Diabetes mellitus accompanies with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Considering the beneficial antidiabetic potential of Nigella sativum (NS , this research study was conducted to evaluate the effect of chronic consumption of NS on learning and memory in diabetic rats using passive avoidance and Y-maze tests. Methods: Male Wistar rats were randomly divided into control, NS-treated control, diabetic, and NS-treated diabetic groups. NS treatment continued for 1 month. For induction of diabetes, streptozotocin was injected i.p. at a single dose of 60 mg/kg. For evaluation of learning and memory, initial latency (IL and step-through latency (STL were determined at the end of study using passive avoidance test. Meanwhile, alternation behavior percentage was determined using Y maze. Results: There was a significant increase (p<0.05 in IL in diabetic and NS-treated diabetic groups after 4 weeks as compared to control group. In this respect, there was no significant difference between diabetic and NS-treated diabetic groups. On the other hand, STL significantly decreased (p<0.05 in diabetic group and significantly increased (p<0.01 in NS-treated diabetic group as compared to control group at the end of study. In addition, results of Y-maze test showed that there is a significant difference between diabetic and NS-treated diabetic groups (p<0.05 regarding alternation behavior. Discussion: In summary, chronic oral administration of NS could enhance the consolidation and recall capability of stored information and spatial memory in diabetic animals.  

  20. Morris水迷宫测评方法的改进及对快速老化痴呆小鼠SAMP8认知功能的再评价%Improvements of Morris Water Maze Evaluation Method and Re-evaluation of the Rapid Aaging Dementia SAMP8 Cognitive Function in Mice

    Institute of Scientific and Technical Information of China (English)

    刘金凤; 聂坤; 栗振杰; 徐思思; 张莹; 孙金平; 张雪竹

    2013-01-01

    Objective: To improve evaluation of the Morris water maze,which make it more suitable for the e-valuation of the cognitive function of mice. And re-evaluate the cognitive function of the rapid aging dementia mice the SAMP8 (senescence accelerated mouse prone 8). Methods: The SAMP8 group and its homologous normal control mice SAMR1 (senescence accelerated mouse resistant 1) were taken as the research object,and the e-valuation of the Morris water maze conditions was optimized. The effect of the mice spatial reference memory capacity by into water point position,the number of daily swim,test order,color and ect were researched. Results: The SAMP8 mice escape latency in each part of the test significantly was longer than SAMR1 mice. SAMP8 mice swam slower than SAMR1 mice. SAMP8 mice their own swimming speed remained stable during the test. Groups latency show no difference on the first day of change the test method.The SAMP8 mice search strategy were mostly random type and edge-type while the SAMR1 mice were linear type and tend type. Conclusion: Explore trials interspersed in hidden and reverse platform test is more effective in test mice short-term learning memory abilities. The scores of the first day after changing test method can not be the standard of evaluate the learning and memory abilities of mice. 4-5 times a day, the number of training does not affect the swimming speed of the mice. SAMP8 mice is a good animal model to study age-related learning and memory deficits.%目的 改进Morris水迷宫的测评方法,使之更适于评价小鼠的认知功能,并对快速老化痴呆小鼠SAMP8的认知功能进行再评价.方法 以SAMP8组及其正常同源对照小鼠SAMR1为研究对象,优化Morris水迷宫的测评条件,研究入水点位置、每日游泳次数、试验次序、颜色等对其空间参考记忆能力的影响.结果 SAMP8小鼠在各部分试验的逃避潜伏期明显长于SAMR1小鼠;SAMP8小鼠比SAMR1小鼠的游泳速度慢,自身

  1. Amphetamine-induced sensitization has little effect on multiple learning paradigms and fails to rescue mice with a striatal learning defect.

    Directory of Open Access Journals (Sweden)

    Kiara C Eldred

    Full Text Available Behavioral sensitization to psychostimulants such as amphetamine (AMPH is associated with synaptic modifications that are thought to underlie learning and memory. Because AMPH enhances extracellular dopamine in the striatum where dopamine and glutamate signaling are essential for learning, one might expect that the molecular and morphological changes that occur in the striatum in response to AMPH, including changes in synaptic plasticity, would affect learning. To ascertain whether AMPH sensitization affects learning, we tested wild-type mice and mice lacking NMDA receptor signaling in striatal medium spiny neurons in several different learning tests (motor learning, Pavlovian association, U-maze escape test with strategy shifting with or without prior sensitization to AMPH. Prior sensitization had minimal effect on learning in any of these paradigms in wild-type mice and failed to restore learning in mutant mice, despite the fact that the mutant mice became sensitized by the AMPH treatment. We conclude that the changes in synaptic plasticity and many other signaling events that occur in response to AMPH sensitization are dissociable from those involved in learning the tasks used in our experiments.

  2. Assessing spatial learning and memory in rodents.

    Science.gov (United States)

    Vorhees, Charles V; Williams, Michael T

    2014-01-01

    Maneuvering safely through the environment is central to survival of almost all species. The ability to do this depends on learning and remembering locations. This capacity is encoded in the brain by two systems: one using cues outside the organism (distal cues), allocentric navigation, and one using self-movement, internal cues and nearby proximal cues, egocentric navigation. Allocentric navigation involves the hippocampus, entorhinal cortex, and surrounding structures; in humans this system encodes allocentric, semantic, and episodic memory. This form of memory is assessed in laboratory animals in many ways, but the dominant form of assessment is the Morris water maze (MWM). Egocentric navigation involves the dorsal striatum and connected structures; in humans this system encodes routes and integrated paths and, when overlearned, becomes procedural memory. In this article, several allocentric assessment methods for rodents are reviewed and compared with the MWM. MWM advantages (little training required, no food deprivation, ease of testing, rapid and reliable learning, insensitivity to differences in body weight and appetite, absence of nonperformers, control methods for proximal cue learning, and performance effects) and disadvantages (concern about stress, perhaps not as sensitive for working memory) are discussed. Evidence-based design improvements and testing methods are reviewed for both rats and mice. Experimental factors that apply generally to spatial navigation and to MWM specifically are considered. It is concluded that, on balance, the MWM has more advantages than disadvantages and compares favorably with other allocentric navigation tasks.

  3. Activation of 5-HT(2C) receptors in the dorsal periaqueductal gray increases antinociception in mice exposed to the elevated plus-maze.

    Science.gov (United States)

    Baptista, Daniela; Nunes-de-Souza, Ricardo Luiz; Canto-de-Souza, Azair

    2012-11-01

    Several findings have pointed to the role of the dorsal periaqueductal gray (dPAG) serotonin 5-HT(1A) and 5-HT(2A-C) receptor subtypes in the modulation of defensive behavior in animals exposed to the elevated plus-maze (EPM). Besides displaying anxiety-like behavior, rodents also exhibit antinociception in the EPM. This study investigated the effects of intra-dPAG injections of 5-HT(1A) and 5-HT(2B/2C) receptor ligands on EPM-induced antinociception in mice. Male Swiss mice received 0.1 μl intra-dPAG injections of vehicle, 5.6 and 10 nmol of 8-OHDPAT, a 5-HT(1A) receptor agonist (Experiment 1), or 0.01, 0.03 and 0.1 nmol of mCPP, a 5-HT(2B/2C) receptor agonist (Experiment 2). Five minutes later, each mouse received an intraperitoneal injection of 0.6% acetic acid (0.1 ml/10 g body weight; nociceptive stimulus) and was individually confined in the open (OA) or enclosed (EA) arms of the EPM for 5 min, during which the number of abdominal writhes induced by the acetic acid was recorded. While intra-dPAG injection of 8-OHDPAT did not change open-arm antinociception (OAA), mCPP (0.01 nmol) enhanced it. Combined injections of ketanserin (10 nmol/0.1 μl), a 5-HT(2A/2C) receptor antagonist, and 0.01 nmol of mCPP (Experiment 3), selectively and completely blocked the OAA enhancement induced by mCPP. Although intra-dPAG injection of mCPP (0.01 nmol) also produced antinociception in EA-confined mice (Experiment 2), this effect was not confirmed in Experiment 3. Moreover, no other compound changed the nociceptive response in EA-confined animals. These results suggest that the 5-HT(2C) receptors located within the PAG play a role in this type of environmentally induced pain inhibition in mice.

  4. L-histidine provokes a state-dependent memory retrieval deficit in mice re-exposed to the elevated plus-maze

    Directory of Open Access Journals (Sweden)

    K.R. Serafim

    2010-01-01

    Full Text Available The effects of L-histidine (LH on anxiety and memory retrieval were investigated in adult male Swiss Albino mice (weight 30-35 g using the elevated plus-maze. The test was performed on two consecutive days: trial 1 (T1 and trial 2 (T2. In T1, mice received an intraperitoneal injection of saline (SAL or LH before the test and were then injected again and retested 24 h later. LH had no effect on anxiety at the dose of 200 mg/kg since there was no difference between the SAL-SAL and LH-LH groups at T1 regarding open-arm entries (OAE and open-arm time (OAT (mean ± SEM; OAE: 4.0 ± 0.71, 4.80 ± 1.05; OAT: 40.55 ± 9.90, 51.55 ± 12.10, respectively; P > 0.05, Kruskal-Wallis test, or at the dose of 500 mg/kg (OAE: 5.27 ± 0.73, 4.87 ± 0.66; OAT: 63.93 ± 11.72, 63.58 ± 10.22; P > 0.05, Fisher LSD test. At T2, LH-LH animals did not reduce open-arm activity (OAE and OAT at the dose of 200 mg/kg (T1: 4.87 ± 0.66, T2: 5.47 ± 1.05; T1: 63.58 ± 10.22; T2: 49.01 ± 8.43 for OAE and OAT, respectively; P > 0.05, Wilcoxon test or at the dose of 500 mg/kg (T1: 4.80 ± 1.60, T2: 4.70 ± 1.04; T1: 51.55 ± 12.10, T2: 43.88 ± 10.64 for OAE and OAT, respectively; P > 0.05, Fisher LSD test, showing an inability to evoke memory 24 h later. These data suggest that LH does not act on anxiety but does induce a state-dependent memory retrieval deficit in mice.

  5. L-histidine provokes a state-dependent memory retrieval deficit in mice re-exposed to the elevated plus-maze.

    Science.gov (United States)

    Serafim, K R; Kishi, M; Canto-de-Souza, A; Mattioli, R

    2010-01-01

    The effects of L-histidine (LH) on anxiety and memory retrieval were investigated in adult male Swiss Albino mice (weight 30-35 g) using the elevated plus-maze. The test was performed on two consecutive days: trial 1 (T1) and trial 2 (T2). In T1, mice received an intraperitoneal injection of saline (SAL) or LH before the test and were then injected again and retested 24 h later. LH had no effect on anxiety at the dose of 200 mg/kg since there was no difference between the SAL-SAL and LH-LH groups at T1 regarding open-arm entries (OAE) and open-arm time (OAT) (mean +/- SEM; OAE: 4.0 +/- 0.71, 4.80 +/- 1.05; OAT: 40.55 +/- 9.90, 51.55 +/- 12.10, respectively; P > 0.05, Kruskal-Wallis test), or at the dose of 500 mg/kg (OAE: 5.27 +/- 0.73, 4.87 +/- 0.66; OAT: 63.93 +/- 11.72, 63.58 +/- 10.22; P > 0.05, Fisher LSD test). At T2, LH-LH animals did not reduce open-arm activity (OAE and OAT) at the dose of 200 mg/kg (T1: 4.87 +/- 0.66, T2: 5.47 +/- 1.05; T1: 63.58 +/- 10.22; T2: 49.01 +/- 8.43 for OAE and OAT, respectively; P > 0.05, Wilcoxon test) or at the dose of 500 mg/kg (T1: 4.80 +/- 1.60, T2: 4.70 +/- 1.04; T1: 51.55 +/- 12.10, T2: 43.88 +/- 10.64 for OAE and OAT, respectively; P > 0.05, Fisher LSD test), showing an inability to evoke memory 24 h later. These data suggest that LH does not act on anxiety but does induce a state-dependent memory retrieval deficit in mice.

  6. Blended learning

    DEFF Research Database (Denmark)

    Dau, Susanne

    2016-01-01

    Blended Learning has been implemented, evaluated and researched for the last decades within different educational areas and levels. Blended learning has been coupled with different epistemological understandings and learning theories, but the fundamental character and dimensions of learning...... in blended learning are still insufficient. Moreover, blended learning is a misleading concept described as learning, despite the fact that it fundamentally is an instructional and didactic approach (Oliver & Trigwell, 2005) addressing the learning environment (Inglis, Palipoana, Trenhom & Ward, 2011......) instead of the learning processes behind. Much of the existing research within the field seems to miss this perspective. The consequence is a lack of acknowledgement of the driven forces behind the context and the instructional design limiting the knowledge foundation of learning in blended learning. Thus...

  7. Blended learning

    DEFF Research Database (Denmark)

    Dau, Susanne

    2016-01-01

    in blended learning are still insufficient. Moreover, blended learning is a misleading concept described as learning, despite the fact that it fundamentally is an instructional and didactic approach (Oliver & Trigwell, 2005) addressing the learning environment (Inglis, Palipoana, Trenhom & Ward, 2011......Blended Learning has been implemented, evaluated and researched for the last decades within different educational areas and levels. Blended learning has been coupled with different epistemological understandings and learning theories, but the fundamental character and dimensions of learning......) instead of the learning processes behind. Much of the existing research within the field seems to miss this perspective. The consequence is a lack of acknowledgement of the driven forces behind the context and the instructional design limiting the knowledge foundation of learning in blended learning. Thus...

  8. Visual-spatial learning impairments are associated with hippocampal PSD-95 protein dysregulation in a mouse model of fragile X syndrome.

    Science.gov (United States)

    Gandhi, Réno M; Kogan, Cary S; Messier, Claude; Macleod, Lindsey S

    2014-03-05

    Fragile X syndrome is the most common cause of inherited intellectual disability and is caused by the lack of fragile X mental retardation protein (FMRP) expression. In-vitro findings in mice and post-mortem autopsies in humans are characterized by dendritic spine abnormalities in the absence of Fmrp/FMRP. Biochemical and electrophysiological studies have identified postsynaptic density protein (PSD)-95 as having an established role in dendritic morphology as well as a molecular target of Fmrp. How Fmrp affects the expression of PSD-95 following behavioral learning is unknown. In the current study, wild type controls and Fmr1 knockout mice were trained in a subset of the Hebb-Williams (H-W) mazes. Dorsal hippocampal PSD-95 protein levels relative to a stable cytoskeleton protein (β-tubulin) were measured. We report a significant upregulation of PSD-95 protein levels in wild type mice, whereas training-related protein increases were blunted in Fmr1 knockout mice. In addition, there was a significant negative correlation between mean total errors on the mazes and PSD-95 protein levels. The coefficient of determination indicated that the mean total errors on the H-W mazes accounted for 35% of the variance in PSD-95 protein levels. These novel findings suggest that reduced PSD-95-associated postsynaptic plasticity may contribute to the learning and memory deficits observed in human fragile X syndrome patients.

  9. Propofol Exposure in Pregnant Rats Induces Neurotoxicity and Persistent Learning Deficit in the Offspring

    Directory of Open Access Journals (Sweden)

    Ming Xiong

    2014-05-01

    Full Text Available Propofol is a general anesthetic widely used in surgical procedures, including those in pregnant women. Preclinical studies suggest that propofol may cause neuronal injury to the offspring of primates if it is administered during pregnancy. However, it is unknown whether those neuronal changes would lead to long-term behavioral deficits in the offspring. In this study, propofol (0.4 mg/kg/min, IV, 2 h, saline, or intralipid solution was administered to pregnant rats on gestational day 18. We detected increased levels of cleaved caspase-3 in fetal brain at 6 h after propofol exposure. The neuronal density of the hippocampus of offspring was reduced significantly on postnatal day 10 (P10 and P28. Synaptophysin levels were also significantly reduced on P28. Furthermore, exploratory and learning behaviors of offspring rats (started at P28 were assessed in open-field trial and eight-arm radial maze. The offspring from propofol-treated dams showed significantly less exploratory activity in the open-field test and less spatial learning in the eight-arm radial maze. Thus, this study suggested that propofol exposure during pregnancy in rat increased cleaved caspsase-3 levels in fetal brain, deletion of neurons, reduced synaptophysin levels in the hippocampal region, and persistent learning deficits in the offspring.

  10. Normal spatial and contextual learning for ketamine-treated rats in the pilocarpine epilepsy model.

    Science.gov (United States)

    McKay, B E; Persinger, M A

    2004-05-01

    Cognitive impairments frequently accompany epileptic disorders. Here, we examine two neuroprotective agents, the noncompetitive NMDA antagonist ketamine and the dopaminergic antagonist acepromazine, for their efficacy in attenuating cognitive impairments in the lithium-pilocarpine (LI-PILO) model of rat limbic epilepsy. Declarative-like cognitive behaviors were assessed in a Morris water maze task that consisted successively of spatial and nonspatial (cued platform) training. Whereas the ketamine-treated (Ket) LI-PILO rats performed equally in all respects to nonseized control rats for the spatial and nonspatial components of the water maze task, the acepromazine-treated (Ace) LI-PILO rats failed to demonstrate learning in either the hidden or cued platform variants of the task and did not demonstrate any place learning in the platform-removed probe trials. We further assessed nondeclarative (associative) cognitive behaviors with a standard contextual fear-conditioning protocol. LI-PILO rats treated with acepromazine failed to learn the Pavlovian relationship; Ket LI-PILO rats performed equivalently to nonseized controls. Cumulatively, these data suggest robust cognitive sparing for LI-PILO rats with pharmacological NMDA receptor antagonism following induction of status epilepticus (SE). This cognitive sparing occurs despite earlier findings that the mean amount of total brain damage with LI-PILO is equivalent for Ket and Ace rats.

  11. A critical review of chronic stress effects on spatial learning and memory.

    Science.gov (United States)

    Conrad, Cheryl D

    2010-06-30

    The purpose of this review is to evaluate the effects of chronic stress on hippocampal-dependent function, based primarily upon studies using young, adult male rodents and spatial navigation tasks. Despite this restriction, variability amongst the findings was evident and how or even whether chronic stress influenced spatial ability depended upon the type of task, the dependent variable measured and how the task was implemented, the type and duration of the stressors, housing conditions of the animals that include accessibility to food and cage mates, and duration from the end of the stress to the start of behavioral assessment. Nonetheless, patterns emerged as follows: For spatial memory, chronic stress impairs spatial reference memory and has transient effects on spatial working memory. For spatial learning, however, chronic stress effects appear to be task-specific: chronic stress impairs spatial learning on appetitively motivated tasks, such as the radial arm maze or holeboard, tasks that evoke relatively mild to low arousal components from fear. But under testing conditions that evoke moderate to strong arousal components from fear, such as during radial arm water maze testing, chronic stress appears to have minimal impairing effects or may even facilitate spatial learning. Chronic stress clearly impacts nearly every brain region and thus, how chronic stress alters hippocampal spatial ability likely depends upon the engagement of other brain structures during behavioral training and testing.

  12. Beneficial effects of the sigma1 receptor agonists igmesine and dehydroepiandrosterone against learning impairments in rats prenatally exposed to cocaine.

    Science.gov (United States)

    Meunier, Johann; Maurice, Tangui

    2004-01-01

    In utero cocaine (IUC) exposure results in offspring rats in complex neurochemical and behavioral alterations, particularly affecting learning and memory processes. We examined here the impact of IUC exposure on memory functions in male and female offspring rats and report that selective sigma(1) (sigma(1)) receptor agonists are effective in reversing the deficits. Dams received a daily cocaine, 20 mg/kg ip, injection between gestational days E17 to E20. Learning was examined in offspring between day P30 and P41 using delayed alternation in the T-maze, water-maze learning and passive avoidance. Both male and female rats prenatally exposed to cocaine showed delayed alternation deficits and impairments of acquisition of a fixed platform position in the water maze, as shown by higher acquisition latencies and diminutions of time spent in the training quadrant during the probe test. The acquisition of a daily changing platform position also demonstrated impaired working memory. Finally, passive avoidance deficits were observed. Pretreatment with the synthetic sigma(1) agonist igmesine (0.1-1 mg/kg ip) or the neuroactive steroid dehydroepiandrosterone (DHEA 10-40 mg/kg ip) reversed the prenatal cocaine-induced learning deficits in offspring rats for each test. The sigma(1) antagonist BD1063 (1 mg/kg ip) failed to affect performances alone but blocked the igmesine and DHEA effects, confirming the involvement of the sigma(1) receptor. IUC exposure thus results in marked memory deficits, affecting spatial and nonspatial short- and long-term memories in juvenile male and female offspring rats. The activation of the sigma(1) neuromodulatory receptor allows a complete behavioral recovery of the memory functions in prenatally cocaine-exposed rats.

  13. The anterior claustrum and spatial reversal learning in rats.

    Science.gov (United States)

    Grasby, Katrina; Talk, Andrew

    2013-03-07

    The claustrum is a small structure of poorly understood function situated subcortically in the basal forebrain. The fact that it is extensively and reciprocally connected with the cerebral cortex has led to suggestions that it is involved in coordination of cortical activity. In this study, we created excitotoxic lesions to the anterior claustrum of rats and tested performance on three tasks that involve neural processing in one or more frontal and limbic cortical structures. We tested reversal learning and spatial working memory in a water maze and tested latent inhibition using conditioned taste aversion. Lesioned rats were not impaired at acquiring the initial location of the platform in a water maze, but were impaired at acquiring a switched location in the reversal phase. The lesioned rats also exhibited an increased rate of perseverance errors compared to control rats during reversal. Lesioned rats were not impaired in the working memory task or latent inhibition. These results indicate that cell loss in the claustrum may lead to deficits in behavioral flexibility, and are consistent with theories of claustral function that suggest it may help coordinate information necessary for at least some cortical-dependent tasks.

  14. Teste de labirinto: instrumento de análise na aquisição de uma habilidade motora Maze test: instrument for analyzing the acquisition of motor skills

    Directory of Open Access Journals (Sweden)

    DE Souza

    2006-09-01

    Full Text Available CONTEXTO: A análise da aquisição de uma habilidade motora através de instrumento simples e fácil pode auxiliar no diagnóstico e no tratamento fisioterapêutico. OBJETIVO: O estudo se propôs a verificar se o teste de labirinto pode ser utilizado como um instrumento de análise na aquisição de uma habilidade motora, através de medidas, tais como, tempo de execução e número de tentativas para estabilizar o desempenho, sob a influência de pistas visuais. MÉTODO: A amostra consistiu de 70 estudantes universitários saudáveis do sexo masculino, de 20 ± 2 anos, divididos em dois grupos que fizeram testes de labirinto com e sem pistas visuais. Foram realizadas 30 tentativas e dois testes de retenção. Os dados foram analisados pela ANOVA two-way de medidas repetidas (Newman-Keuls post hoc. RESULTADOS: Verificou-se diferença significativa no tempo de execução entre as tentativas com estabilização do desempenho a partir da 8ª tentativa no labirinto sem pistas e da 6ª tentativa no labirinto com pistas, se mantendo após os testes de retenção. No teste de labirinto com pistas a estabilização ocorreu mais cedo e o tempo de execução do movimento foi maior. CONCLUSÕES: As evidências encontradas mostraram que o teste de labirinto permite identificar a quantidade adequada de prática para treinar uma habilidade motora e verificar a influência da pista visual na estabilização do desempenho, sugerindo um instrumento a ser utilizado na FisioterapiaBACKGROUND: Analysis of the acquisition of motor skills by means of a simple and easily used instrument may assist in physiotherapeutic diagnosis and treatment. OBJECTIVE: To verify whether the maze test can be used as an instrument for analyzing the acquisition of motor skills, by means of measurements such as the time taken and number of attempts required for performance stabilization, under the influence of visual clues. METHOD: The sample consisted of 70 healthy male university

  15. Cooperative Learning

    Institute of Scientific and Technical Information of China (English)

    桑莹莹

    2015-01-01

    This paper is about the cooperative learning as a teaching method in a second language learning class. It mainly talks about the background, foundation, features, definitions, components, goals, advantages and disadvantages of cooperative learning. And as the encounter of the disadvantages in cooperative learning, this paper also proposes some strategies.

  16. The total triterpenoid saponins of Xanthoceras sorbifolia improve learning and memory impairments through against oxidative stress and synaptic damage.

    Science.gov (United States)

    Ji, Xue-Fei; Chi, Tian-Yan; Liu, Peng; Li, Lu-Yi; Xu, Ji-Kai; Xu, Qian; Zou, Li-Bo; Meng, Da-Li

    2017-02-15

    X. sorbifolia is a widely cultivated ecologicalcrop in the north of China which is used to produce biodiesel fuel. It also possesses special medicinal value and has attracted keen interests of researchers to explore its bioactivity. To extract the total triterpenoid saponins from the husk of X. sorbifolia (TSX) and investigate its effects on Alzheimer's disease (AD). TSX was prepared via modern extraction techniques. Its effects on two AD animal models, as well as the preliminary mechanism were investigated comprehensively. The behavioral experiments including Y maze test, Morris water maze test and passive avoidance test were performed to observe the learning and memory abilities of the animals. ELISA assays, transmission electron microscope observation and Western blotting were employed in mechanism study. TSX, the main composition of X. sorbifolia, accounted for 88.77% in the plant material. It could significantly increase the spontaneous alternation in Y maze test (F (6, 65)=3.209, Pmemory. The preliminary mechanism might associate with its protection effects against oxidative stress damage, cholinergic system deficiency and synaptic damage. TSX are perfectly suitable for AD patients as medicine or functional food, which would be a new candidate to treat AD. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. Place field repetition and spatial learning in a multicompartment environment.

    Science.gov (United States)

    Grieves, Roddy M; Jenkins, Bryan W; Harland, Bruce C; Wood, Emma R; Dudchenko, Paul A

    2016-01-01

    Recent studies have shown that place cells in the hippocampus possess firing fields that repeat in physically similar, parallel environments. These results imply that it should be difficult for animals to distinguish parallel environments at a behavioral level. To test this, we trained rats on a novel odor-location task in an environment with four parallel compartments which had previously been shown to yield place field repetition. A second group of animals was trained on the same task, but with the compartments arranged in different directions, an arrangement we hypothesised would yield less place field repetition. Learning of the odor-location task in the parallel compartments was significantly impaired relative to learning in the radially arranged compartments. Fewer animals acquired the full discrimination in the parallel compartments compared to those trained in the radial compartments, and the former also required many more sessions to reach criterion compared to the latter. To confirm that the arrangement of compartments yielded differences in place cell repetition, in a separate group of animals we recorded from CA1 place cells in both environments. We found that CA1 place cells exhibited repeated fields across four parallel local compartments, but did not do so when the same compartments were arranged radially. To confirm that the differences in place field repetition across the parallel and radial compartments depended on their angular arrangement, and not incidental differences in access to an extra-maze visual landmark, we repeated the recordings in a second set of rats in the absence of the orientation landmark. We found, once again, that place fields showed repetition in parallel compartments, and did not do so in radially arranged compartments. Thus place field repetition, or lack thereof, in these compartments was not dependent on extra-maze cues. Together, these results imply that place field repetition constrains spatial learning.

  18. Choline acetyltransferase in the hippocampus is associated with learning strategy preference in adult male rats.

    Science.gov (United States)

    Hawley, Wayne R; Witty, Christine F; Daniel, Jill M; Dohanich, Gary P

    2015-08-01

    One prin