An old test for new neurons: refining the Morris water maze to study the functional relevance of adult hippocampal neurogenesis

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Alexander eGarthe

2013-05-01

Full Text Available The Morris water maze represents the de-facto standard for testing hippocampal function in laboratory rodents. In the field of adult hippocampal neurogenesis, however, using this paradigm to assess the functional relevance of the new neurons yielded surprisingly inconsistent results. While some authors found aspects of water maze performance to be linked to adult neurogenesis, others obtained different results or could not demonstrate any effect of manipulating adult neurogenesis.In this review we discuss evidence that the large diversity of protocols and setups used is an important aspect in interpreting the differences in the results that have been obtained. Even simple parameters such as pool size, number and configuration of visual landmarks, or number of trials can become highly relevant for getting the new neurons involved at all. Sets of parameters are often chosen with implicit or explicit concepts in mind and these might lead to different views on the function of adult-generated neurons.We propose that the classical parameters usually used to measure spatial learning performance in the water maze might not be particularly well suited to sensitively and specifically detect the supposedly highly specific functional changes elicited by the experimental modulation of adult hippocampal neurogenesis. As adult neurogenesis is supposed to affect specific aspects of information processing only in the hippocampus, any claim for a functional relevance of the new neurons has to be based on hippocampus-specific parameters. We also placed a special emphasis on the fact that the DG facilitates the differentiation between contexts as opposed to just differentiating places.In conclusion, while the Morris water maze has proven to be one of the most effective testing paradigms to assess hippocampus-dependent spatial learning, new and more specific questions ask for new parameters. Therefore, the full potential of the water maze task remains to be tapped.

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

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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 this study, we investigated the influence of aerobic fitness on hippocampal size and subsequent learning and memory, including visuospatial memory using a human analogue of the Morris Water Task, in 34 adolescents. Results showed that higher aerobic fitness predicted better learning on the virtual Morris Water Task and larger hippocampal volumes. No relationship between virtual Morris Water Task memory recall and aerobic fitness was detected. Aerobic fitness, however, did not relate to global brain volume, or verbal learning, which might suggest some specificity of the influence of aerobic fitness on the adolescent brain. This study provides a direct translational approach to the existing animal literature on exercise, as well as adds to the sparse research that exists on how aerobic exercise impacts the developing human brain and memory. PMID:22610054

Aerobic fitness relates to learning on a virtual Morris Water Task and hippocampal volume in adolescents.

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Herting, Megan M; Nagel, Bonnie J

2012-08-01

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 this study, we investigated the influence of aerobic fitness on hippocampal size and subsequent learning and memory, including visuospatial memory using a human analogue of the Morris Water Task, in 34 adolescents. Results showed that higher aerobic fitness predicted better learning on the virtual Morris Water Task and larger hippocampal volumes. No relationship between virtual Morris Water Task memory recall and aerobic fitness was detected. Aerobic fitness, however, did not relate to global brain volume or verbal learning, which might suggest some specificity of the influence of aerobic fitness on the adolescent brain. This study provides a direct translational approach to the existing animal literature on exercise, as well as adds to the sparse research that exists on how aerobic exercise impacts the developing human brain and memory. Published by Elsevier B.V.

Rolling block mazes are PSPACE-complete

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Buchin, K.; Buchin, M.

2012-01-01

In a rolling block maze, one or more blocks lie on a rectangular board with square cells. In most mazes, the blocks have size k × m × n where k, m, n are integers that determine the size of the block in terms of units of the size of the board cells. The task of a rolling block maze is to roll a

Remembering Places in Space: A Human Analog Study of the Morris Water Maze

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Fitting, Sylvia; Allen, Gary L.; Wedell, Douglas H.

We conducted a human analog study of the Morris Water Maze, with individuals indicating a remembered location in a 3 m diameter arena over different intervals of time and with different memory loads. The primary focus of the study was to test a theory of how varying cue location and number of cues affects memory for spatial location. As expected, memory performance, as measured by proximity to the actual location, was negatively affected by increasing memory load, increasing delay interval, and decreasing the number of cues. As memory performance decremented, bias effects increased and were in accordance with the cue-based memory model described by Fitting, Wedell and Allen (2005). Specifically, remembered locations were biased toward the nearest cue and error decreased with more cues. These results demonstrate that localization processes that apply to small two-dimensional task fields may generalize to a larger traversable task field.

Spatial memory impairment in Morris water maze after electroconvulsive seizures.

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Svensson, Maria; Hallin, Thord; Broms, Jonas; Ekstrand, Joakim; Tingström, Anders

2017-02-01

Electroconvulsive therapy (ECT) is one of the most efficient treatments for severe major depression, but some patients suffer from retrograde memory loss after treatment. Electroconvulsive seizures (ECS), an animal model of ECT, have repeatedly been shown to increase hippocampal neurogenesis, and multiple ECS treatments cause retrograde amnesia in hippocampus-dependent memory tasks. Since recent studies propose that addition of newborn hippocampal neurons might degrade existing memories, we investigated whether the memory impairment after multiple ECS treatments is a cumulative effect of repeated treatments, or if it is the result of a delayed effect after a single ECS. We used the hippocampus-dependent memory task Morris water maze (MWM) to evaluate spatial memory. Rats were exposed to an 8-day training paradigm before receiving either a single ECS or sham treatment and tested in the MWM 24 h, 72 h, or 7 days after this treatment, or multiple (four) ECS or sham treatments and tested 7 days after the first treatment. A single ECS treatment was not sufficient to cause retrograde amnesia whereas multiple ECS treatments strongly disrupted spatial memory in the MWM. The retrograde amnesia after multiple ECS is a cumulative effect of repeated treatments rather than a delayed effect after a single ECS.

Isolated core vs. superficial cooling effects on virtual maze navigation.

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Payne, Jennifer; Cheung, Stephen S

2007-07-01

Cold impairs cognitive performance and is a common occurrence in many survival situations. Altered behavior patterns due to impaired navigation abilities in cold environments are potential problems in lost-person situations. We investigated the separate effects of low core temperature and superficial cooling on a spatially demanding virtual navigation task. There were 12 healthy men who were passively cooled via 15 degrees C water immersion to a core temperature of 36.0 degrees C, then transferred to a warm (40 degrees C) water bath to eliminate superficial shivering while completing a series of 20 virtual computer mazes. In a control condition, subjects rested in a thermoneutral (approximately 35 degrees C) bath for a time-matched period before being transferred to a warm bath for testing. Superficial cooling and distraction were achieved by whole-body immersion in 35 degree water for a time-matched period, followed by lower leg immersion in 10 degree C water for the duration of the navigational tests. Mean completion time and mean error scores for the mazes were not significantly different (p > 0.05) across the core cooling (16.59 +/- 11.54 s, 0.91 +/- 1.86 errors), control (15.40 +/- 8.85 s, 0.82 +/- 1.76 errors), and superficial cooling (15.19 +/- 7.80 s, 0.77 +/- 1.40 errors) conditions. Separately reducing core temperature or increasing cold sensation in the lower extremities did not influence performance on virtual computer mazes, suggesting that navigation is more resistive to cooling than other, simpler cognitive tasks. Further research is warranted to explore navigational ability at progressively lower core and skin temperatures, and in different populations.

Harmine treatment enhances short-term memory in old rats: Dissociation of cognition and the ability to perform the procedural requirements of maze testing.

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Mennenga, Sarah E; Gerson, Julia E; Dunckley, Travis; Bimonte-Nelson, Heather A

2015-01-01

Harmine is a naturally occurring monoamine oxidase inhibitor that has recently been shown to selectively inhibit the dual-specificity tyrosine-(Y)-phosphorylation-regulated kinase 1A (DYRK1A). We investigated the cognitive effects of 1mg (low) Harmine and 5mg (high) Harmine using the delayed-match-to-sample (DMS) asymmetrical 3-choice water maze task to evaluate spatial working and recent memory, and the Morris water maze task (MM) to test spatial reference memory. Animals were also tested on the visible platform task, a water-escape task with the same motor, motivational, and reinforcement components as the other tasks used to evaluate cognition, but differing in its greater simplicity and that the platform was visible above the surface of the water. A subset of the Harmine-high treated animals showed clear motor impairments on all behavioral tasks, and the visible platform task confirmed a lack of competence to perform the procedural components of water maze testing. After excluding animals from the high dose group that could not perform the procedural components of a swim task, it was revealed that both high- and low-dose treatment with Harmine enhanced performance on the latter portion of DMS testing, but had no effect on MM performance. Thus, this study demonstrates the importance of confirming motor and visual competence when studying animal cognition, and verifies the one-day visible platform task as a reliable measure of ability to perform the procedural components necessary for completion of a swim task. Copyright © 2014. Published by Elsevier Inc.

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

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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.

Similar reliability and equivalent performance of female and male mice in the open field and water-maze place navigation task

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Fritz, Ann-Kristina; Amrein, Irmgard; Wolfer, David P.

2017-01-01

Although most nervous system diseases affect women and men differentially, most behavioral studies using mouse models do not include subjects of both sexes. Many researchers worry that data of female mice may be unreliable due to the estrous cycle. Here, we retrospectively evaluated sex effects on coefficient of variation (CV) in 5,311 mice which had performed the same place navigation protocol in the water-maze and in 4,554 mice tested in the same open field arena. Confidence intervals for C...

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

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Oguz Mutlu

2015-01-01

Full Text Available 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, 1 H -[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.

Use of an Eight-arm Radial Water Maze to Assess Working and Reference Memory Following Neonatal Brain Injury

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Penley, Stephanie C.; Gaudet, Cynthia M.; Threlkeld, Steven W.

2013-01-01

Working and reference memory are commonly assessed using the land based radial arm maze. However, this paradigm requires pretraining, food deprivation, and may introduce scent cue confounds. The eight-arm radial water maze is designed to evaluate reference and working memory performance simultaneously by requiring subjects to use extra-maze cues to locate escape platforms and remedies the limitations observed in land based radial arm maze designs. Specifically, subjects are required to avoid ...

Delayed-matching-to-place Task in a Dry Maze to Measure Spatial Working Memory in Mice.

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Feng, Xi; Krukowski, Karen; Jopson, Timothy; Rosi, Susanna

2017-07-05

The delayed-matching-to-place (DMP) dry maze test is a variant of DMP water maze (Steele and Morris, 1999; Faizi et al. , 2012) which measures spatial working/episodic-like learning and memory that depends on both hippocampal and cortical functions (Wang and Morris, 2010; Euston et al. , 2012). Using this test we can detect normal aging related spatial working memory decline, as well as trauma induced working memory deficits. Furthermore, we recently reported that fractionated whole brain irradiation does not affect working memory in mice (Feng et al. , 2016). Here we describe the experimental setup and procedures of this behavioral test.

Interaction between the nature of the information and the cognitive requirement of the task in problem solving in mice.

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Wolff, Mathieu; Benhassine, Narimane; Costet, Pierre; Segu, Louis; Buhot, Marie-Christine

2004-11-01

The Morris water maze and the radial-arm maze are two of the most frequently employed behavioral tasks used to assess spatial memory in rodents. In this study, we describe two new behavioral tasks in a radial-arm water maze enabling to combine the advantages of the Morris water maze and the radial-arm maze. In both tasks, spatial and nonspatial learning was assessed and the only task parameter that varied was the nature of the information available which was either spatial (various distal extra-maze cues) or nonspatial (visual intra-maze patterns). In experiment 1, 129T2/Sv mice were able to learn three successive pairwise discriminations [(1) A+/B-, (2) B+/C-, (3) C+/A-] with the same efficiency in both modalities (i.e. spatial and nonspatial modalities). Probe-trials at the end of each of these discriminations revealed particular features of this transverse-patterning-like procedure. In experiment 2, another group of 129T2/Sv mice was submitted to a delayed matching-to-sample working memory task. Mice were able to learn the task and were then able to show resistance to temporal interference as long as 60 min in the spatial modality but they failed to acquire the task in the nonspatial modality. The fact that the nonspatial information was exactly the same in both experiments highlights the existence of an interaction between the cognitive requirements of the task and the nature of the information.

CaMKII binding to GluN2B is important for massed spatial learning in the Morris water maze [v1; ref status: indexed, http://f1000r.es/3ud

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Ivar S. Stein

2014-08-01

Full Text Available Learning and memory as well as long-term potentiation (LTP depend on Ca2+ influx through the NMDA-type glutamate receptor (NMDAR and the resulting activation of the Ca2+ and calmodulin-dependent protein kinase (CaMKII. Ca2+ influx via the NMDAR triggers CaMKII binding to the NMDAR for enhanced CaMKII accumulation at post-synaptic sites that experience heightened activity as occurring during LTP. Previously, we generated knock-in (KI mice in which we replaced two residues in the NMDAR GluN2B subunit to impair CaMKII binding to GluN2B. Various forms of LTP at the Schaffer collateral synapses in CA1 are reduced by 50%. Nevertheless, working memory in the win-shift 8 arm maze and learning of the Morris water maze (MWM task was normal in the KI mice although recall of the task was impaired in these mice during the period of early memory consolidation. We now show that massed training in the MWM task within a single day resulted in impaired learning. However, learning and recall of the Barnes maze task and contextual fear conditioning over one or multiple days were surprisingly unaffected. The differences observed in the MWM compared to the Barnes maze and contextual fear conditioning suggest a differential involvement of CaMKII and the specific interaction with GluN2B, probably depending on varying degrees of stress, cognitive demand or even potentially different plasticity mechanisms associated with the diverse tasks.

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

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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. Copyright © 2014 Elsevier B.V. All rights reserved.

Disentangling the cognitive components supporting Austin Maze performance in left versus right temporal lobe epilepsy.

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Hocking, Julia; Thomas, Hannah J; Dzafic, Ilvana; Williams, Rebecca J; Reutens, David C; Spooner, Donna M

2013-12-01

Neuropsychological tests requiring patients to find a path through a maze can be used to assess visuospatial memory performance in temporal lobe pathology, particularly in the hippocampus. Alternatively, they have been used as a task sensitive to executive function in patients with frontal lobe damage. We measured performance on the Austin Maze in patients with unilateral left and right temporal lobe epilepsy (TLE), with and without hippocampal sclerosis, compared to healthy controls. Performance was correlated with a number of other neuropsychological tests to identify the cognitive components that may be associated with poor Austin Maze performance. Patients with right TLE were significantly impaired on the Austin Maze task relative to patients with left TLE and controls, and error scores correlated with their performance on the Block Design task. The performance of patients with left TLE was also impaired relative to controls; however, errors correlated with performance on tests of executive function and delayed recall. The presence of hippocampal sclerosis did not have an impact on maze performance. A discriminant function analysis indicated that the Austin Maze alone correctly classified 73.5% of patients as having right TLE. In summary, impaired performance on the Austin Maze task is more suggestive of right than left TLE; however, impaired performance on this visuospatial task does not necessarily involve the hippocampus. The relationship of the Austin Maze task with other neuropsychological tests suggests that differential cognitive components may underlie performance decrements in right versus left TLE. © 2013.

Beta-hydroxy-beta-methylbutyrate (HMB) ameliorates age-related deficits in water maze performance, especially in male rats.

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Kougias, Daniel G; Hankosky, Emily R; Gulley, Joshua M; Juraska, Janice M

2017-03-01

Beta-hydroxy-beta-methylbutyrate (HMB) is commonly supplemented to maintain muscle in elderly and clinical populations and has potential as a nootropic. Previously, we have shown that in both male and female rats, long-term HMB supplementation prevents age-related dendritic shrinkage within the medial prefrontal cortex (mPFC) and improves cognitive flexibility and working memory performance that are both age- and sex-specific. In this study, we further explore the cognitive effects by assessing visuospatial learning and memory with the Morris water maze. Female rats were ovariectomized at 11months of age to model human menopause. At 12months of age, male and female rats received relatively short- or long-term (1- or 7-month) dietary HMB (450mg/kg/dose) supplementation twice a day prior to testing. Spatial reference learning and memory was assessed across four days in the water maze with four trials daily and a probe trial on the last day. Consistent with previous work, there were age-related deficits in water maze performance in both sexes. However, these deficits were ameliorated in HMB-treated males during training and in both sexes during probe trial performance. Thus, HMB supplementation prevented the age-related decrement in water maze performance, especially in male rats. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluating spatial memory function in mice: a within-subjects comparison between the water maze test and its adaptation to dry land.

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Llano Lopez, L; Hauser, J; Feldon, J; Gargiulo, P A; Yee, B K

2010-05-01

The Morris water maze (WM) is a common spatial memory test in rats. It has been adapted for evaluating genetic manipulations in mice. One major acknowledged problem of this cross-species translation is floating. We investigated here in mice the feasibility and practicality of an alternative paradigm-the cheeseboard (CB), which is a dry version of the WM, in a within-subject design allowing direct comparison with the conventional WM. Under identical task demands (reference or working memory), mice learned in the CB as efficiently as in the WM. Furthermore, individual differences in learning rate correlated between the two reference memory tests conducted separately in the two mazes. However, no such correlation was found with respect to reference memory retention or working memory performance. This study demonstrated that the CB is an effective alternative to the WM as spatial cognition test. Additional tests in the CB confirmed that the mice relied on extra maze cues in their spatial search. We would recommend the CB as a valuable addition to, rather than a replacement of the WM in phenotyping transgenic mice, because the two apparatus might diverge in the ability to detect individual differences in various domains of mnemonic functions.

Spontaneous Recovery of Human Spatial Memory in a Virtual Water Maze

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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…

A computer vision-based automated Figure-8 maze for working memory test in rodents.

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Pedigo, Samuel F; Song, Eun Young; Jung, Min Whan; Kim, Jeansok J

2006-09-30

The benchmark test for prefrontal cortex (PFC)-mediated working memory in rodents is a delayed alternation task utilizing variations of T-maze or Figure-8 maze, which requires the animals to make specific arm entry responses for reward. In this task, however, manual procedures involved in shaping target behavior, imposing delays between trials and delivering rewards can potentially influence the animal's performance on the maze. Here, we report an automated Figure-8 maze which does not necessitate experimenter-subject interaction during shaping, training or testing. This system incorporates a computer vision system for tracking, motorized gates to impose delays, and automated reward delivery. The maze is controlled by custom software that records the animal's location and activates the gates according to the animal's behavior and a control algorithm. The program performs calculations of task accuracy, tracks movement sequence through the maze, and provides other dependent variables (such as running speed, time spent in different maze locations, activity level during delay). Testing in rats indicates that the performance accuracy is inversely proportional to the delay interval, decreases with PFC lesions, and that animals anticipate timing during long delays. Thus, our automated Figure-8 maze is effective at assessing working memory and provides novel behavioral measures in rodents.

The psychostimulant modafinil facilitates water maze performance and augments synaptic potentiation in dentate gyrus.

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Tsanov, Marian; Lyons, Declan G; Barlow, Sally; González Reyes, Rodrigo E; O'Mara, Shane M

2010-01-01

Modafinil is a psychostimulant drug used widely for the treatment of narcolepsy, which also has additional positive effects on cognition. Here, we investigate the effects of modafinil on behavioural performance and synaptic plasticity in rats. Improved acquisition in the water maze task was observed in animals that underwent chronic treatment with modafinil. We found that the distance traveled and escape latency were reduced after the first day in chronically-treated rats, compared to controls. Importantly, swim velocity was similar for both groups, excluding pharmacological effects on motor skills. We also found that modafinil increases synaptic plasticity in the dentate gyrus of urethane-anaesthetized rats; modafinil induced a robust augmentation of the population spike, evident after application of 2 bursts of 200 Hz high-frequency stimulation. Furthermore, the modafinil-dependent enhancement of postsynaptic potentials correlated selectively with theta rhythm augmentation. We propose that modafinil may facilitate hippocampal-associated spatial representation via increased theta-related hippocampal plasticity. Copyright 2010 Elsevier Ltd. All rights reserved.

Intelligence-Augmented Rat Cyborgs in Maze Solving.

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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.

Intelligence-Augmented Rat Cyborgs in Maze Solving.

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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.

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

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Phillips, John B; Youmans, Paul W; Muheim, Rachel; Sloan, Kelly A; Landler, Lukas; Painter, Michael S; Anderson, Christopher R

2013-01-01

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.

Learning spatial orientation tasks in the radial-maze and structural variation in the hippocampus in inbred mice

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Schwegler Herbert

2005-04-01

Full Text Available Abstract In the present paper we review a series of experiments showing that heritable variations in the size of the hippocampal intra- and infrapyramidal mossy fiber (IIPMF terminal fields correlate with performance in spatial, but not non-spatial radial-maze tasks. Experimental manipulation of the size of this projection by means of early postnatal hyperthyroidism produces the effects predicted from the correlations obtained with inbred mouse strains. Although the physiological mechanisms behind these correlations are unknown as yet, several lines of evidence indicate that these correlations are causal.

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. © Georg Thieme Verlag KG Stuttgart · New York.

Elevated mazes as animal models of anxiety: effects of serotonergic agents

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Simone H. Pinheiro

2007-03-01

Full Text Available This article reviews reported results about the effects of drugs that act upon the serotonergic neurotransmission measured in three elevated mazes that are animal models of anxiety. A bibliographic search has been performed in MEDLINE using different combinations of the key words X-maze, plus-maze, T-maze, serotonin and 5-HT, present in the title and/or the abstract, with no time limit. From the obtained abstracts, several publications were excluded on the basis of the following criteria: review articles that did not report original results, species other than the rat, intracerebral drug administration alone, genetically manipulated rats, and animals having any kind of experimental pathology. The reported results indicate that the effect of drugs on the inhibitory avoidance task performed in the elevated T-maze and on the spatio temporal indexes of anxiety measured in the X and plus mazes correlate with their effect in patients diagnosed with generalized anxiety disorder. In contrast, the drug effects on the one-way escape task in the elevated T-maze predict the drug response of panic disorder patients. Overall, the drug effects assessed with the avoidance task in the T-maze are more consistent than those measured through the anxiety indexes of the X and plus mazes. Therefore, the elevated T-maze is a promising animal model of generalized anxiety and panic disorder.No presente artigo, revisamos resultados publicados relatando efeitos de drogas que atuam na neurotransmissão serotonérgica medidos em três labirintos elevados, que são modelos animais de ansiedade. Realizamos uma busca bibliográfica no MEDLINE, usando diferentes combinações das palavras-chave: X-maze, plus-maze, T-maze, serotonin e 5-HT, presentes no título ou no resumo, sem limite de tempo. Dos resumos obtidos, vários foram excluídos com base nos seguintes critérios: artigos de revisão que não continham resultados originais, espécies diferentes do rato, apenas inje

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

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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.

Use of an eight-arm radial water maze to assess working and reference memory following neonatal brain injury.

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Penley, Stephanie C; Gaudet, Cynthia M; Threlkeld, Steven W

2013-12-04

Working and reference memory are commonly assessed using the land based radial arm maze. However, this paradigm requires pretraining, food deprivation, and may introduce scent cue confounds. The eight-arm radial water maze is designed to evaluate reference and working memory performance simultaneously by requiring subjects to use extra-maze cues to locate escape platforms and remedies the limitations observed in land based radial arm maze designs. Specifically, subjects are required to avoid the arms previously used for escape during each testing day (working memory) as well as avoid the fixed arms, which never contain escape platforms (reference memory). Re-entries into arms that have already been used for escape during a testing session (and thus the escape platform has been removed) and re-entries into reference memory arms are indicative of working memory deficits. Alternatively, first entries into reference memory arms are indicative of reference memory deficits. We used this maze to compare performance of rats with neonatal brain injury and sham controls following induction of hypoxia-ischemia and show significant deficits in both working and reference memory after eleven days of testing. This protocol could be easily modified to examine many other models of learning impairment.

Tactile maze solving in congenitally blind individuals

DEFF Research Database (Denmark)

Gagnon, Léa; Kupers, Ron; Schneider, Fabien C

2010-01-01

and environmental cues such as temperature and echolocation. We hypothesize that by limiting these cues, blind individuals will lose their advantage compared with controls in spatial navigation tasks. We therefore evaluated the performance of blind and sighted individuals in small-scale, tactile multiple T mazes....... Our results show that blindfolded sighted controls outperformed blind participants in the route-learning tasks. This suggests that, contrary to indoor large-scale spaces, navigational skills inside small-scale spaces benefit from visual experience....

Negative transfer effects between reference memory and working memory training in the water maze in C57BL/6 mice.

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Serrano Sponton, Lucas Ezequiel; Soria, Gonzalo Jose; Dubroqua, Sylvain; Singer, Philipp; Feldon, Joram; Gargiulo, Pascual A; Yee, Benjamin K

2018-02-26

The water maze is one of the most widely employed spatial learning paradigms in the cognitive profiling of genetically modified mice. Oftentimes, tests of reference memory (RM) and working memory (WM) in the water maze are sequentially evaluated in the same animals. However, critical difference in the rules governing efficient escape from the water between WM and RM tests is expected to promote the adoption of incompatible mnemonic or navigational strategies. Hence, performance in a given test is likely poorer if it follows the other test instead of being conducted first. Yet, the presence of such negative transfer effects (or proactive interference) between WM and RM training in the water maze is often overlooked in the literature. To gauge whether this constitutes a serious concern, the present study determined empirically the magnitude, persistence, and directionality of the transfer effect in wild-type C57BL/6 mice. We contrasted the order of tests between two cohorts of mice. Performance between the two cohorts in the WM and RM tests were then separately compared. We showed that prior training of either test significantly reduced performance in the subsequent one. The statistical effect sizes in both directions were moderate to large. Although extended training could overcome the deficit, it could re-emerge later albeit in a more transient fashion. Whenever RM and WM water maze tests are conducted sequentially in the same animals - regardless of the test order, extra caution is necessary when interpreting the outcomes in the second test. Counterbalancing test orders between animals is recommended. Copyright © 2017 Elsevier B.V. All rights reserved.

Changing patterns of brain activation during maze learning.

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Van Horn, J D; Gold, J M; Esposito, G; Ostrem, J L; Mattay, V; Weinberger, D R; Berman, K F

1998-05-18

Recent research has found that patterns of brain activation involving the frontal cortex during novel task performance change dramatically following practice and repeat performance. Evidence for differential left vs. right frontal lobe activation, respectively, during episodic memory encoding and retrieval has also been reported. To examine these potentially related issues regional cerebral blood flow (rCBF) was measured in 15 normal volunteers using positron emission tomography (PET) during the naive and practiced performance of a maze task paradigm. SPM analysis indicated a largely right-sided, frontal lobe activation during naive performance. Following training and practice, performance of the same maze task elicited a more posterior pattern of rCBF activation involving posterior cingulate and precuneus. The change in the pattern of rCBF activation between novel and practiced task conditions agrees with results found in previous studies using repeat task methodology, and indicates that the neural circuitry required for encoding novel task information differs from that required when the same task has become familiar and information is being recalled. The right-sided preponderance of activation during naive performance may relate to task novelty and the spatially-based nature of the stimuli, whereas posterior areas activated during repeat performance are those previously found to be associated with visuospatial memory recall. Activation of these areas, however, does not agree with previously reported findings of left-sided activation during verbal episodic memory encoding and right-sided activation during retrieval, suggesting different neural substrates for verbal and visuospatial processing within memory. Copyright 1998 Elsevier Science B.V.

Barnes Maze Procedure for Spatial Learning and Memory in Mice.

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Pitts, Matthew W

2018-03-05

The Barnes maze is a dry-land based rodent behavioral paradigm for assessing spatial learning and memory that was originally developed by its namesake, Carol Barnes. It represents a well-established alternative to the more popular Morris Water maze and offers the advantage of being free from the potentially confounding influence of swimming behavior. Herein, the Barnes maze experimental setup and corresponding procedures for testing and analysis in mice are described in detail.

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

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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...... imaging (fMRI) in congenitally blind and blindfolded sighted participants while they navigated through a tactile multiple T-maze. Both groups learned the maze task at a similar pace. In blind participants, tactile maze navigation was associated with increased BOLD responses in the right hippocampus...

Sex differences in a virtual water maze: an eye tracking and pupillometry study.

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Mueller, Sven C; Jackson, Carl P T; Skelton, Ron W

2008-11-21

Sex differences in human spatial navigation are well known. However, the exact strategies that males and females employ in order to navigate successfully around the environment are unclear. While some researchers propose that males prefer environment-centred (allocentric) and females prefer self-centred (egocentric) navigation, these findings have proved difficult to replicate. In the present study we examined eye movements and physiological measures of memory (pupillometry) in order to compare visual scanning of spatial orientation using a human virtual analogue of the Morris Water Maze task. Twelve women and twelve men (average age=24 years) were trained on a visible platform and had to locate an invisible platform over a series of trials. On all but the first trial, participants' eye movements were recorded for 3s and they were asked to orient themselves in the environment. While the behavioural data replicated previous findings of improved spatial performance for males relative to females, distinct sex differences in eye movements were found. Males tended to explore consistently more space early on while females demonstrated initially longer fixation durations and increases in pupil diameter usually associated with memory processing. The eye movement data provides novel insight into differences in navigational strategies between the sexes.

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

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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.

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

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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.

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

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Natalia Andreevna Krivova

2015-03-01

Full Text Available The Morris water maze (MWM is a tool for assessment of age-related cognitive deficits. In our work, MWM was used for appraisal of cognitive deficits in 11-month-old rats and investigation of the effect exerted by training in the Morris water maze on the redox mechanisms in rat brain parts. Young adult (3-month-old and aged (11-month-old male rats were trained in the water maze. 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.Cognitive deficits were 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 cognitive deficits in aged rats can be reversed by MWM training. 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 responsible for age-related cognitive deficits. 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.

Navigating a Maze with Balance Board and Wiimote

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Fikkert, Wim; Hoeijmakers, Niek; van der Vet, Paul; Nijholt, Anton

Input from the lower body in human-computer interfaces can be beneficial, enjoyable and even entertaining when users are expected to perform tasks simultaneously. Users can navigate a virtual (game) world or even an (empirical) dataset while having their hands free to issue commands. We compared the Wii Balance Board to a hand-held Wiimote for navigating a maze and found that users completed this task slower with the Balance Board. However, the Balance Board was considered more intuitive, easy to learn and ‘much fun’.

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

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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

Neural correlates of olfactory and visual memory performance in 3D-simulated mazes after intranasal insulin application.

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Brünner, Yvonne F; Rodriguez-Raecke, Rea; Mutic, Smiljana; Benedict, Christian; Freiherr, Jessica

2016-10-01

This fMRI study intended to establish 3D-simulated mazes with olfactory and visual cues and examine the effect of intranasally applied insulin on memory performance in healthy subjects. The effect of insulin on hippocampus-dependent brain activation was explored using a double-blind and placebo-controlled design. Following intranasal administration of either insulin (40IU) or placebo, 16 male subjects participated in two experimental MRI sessions with olfactory and visual mazes. Each maze included two separate runs. The first was an encoding maze during which subjects learned eight olfactory or eight visual cues at different target locations. The second was a recall maze during which subjects were asked to remember the target cues at spatial locations. For eleven included subjects in the fMRI analysis we were able to validate brain activation for odor perception and visuospatial tasks. However, we did not observe an enhancement of declarative memory performance in our behavioral data or hippocampal activity in response to insulin application in the fMRI analysis. It is therefore possible that intranasal insulin application is sensitive to the methodological variations e.g. timing of task execution and dose of application. Findings from this study suggest that our method of 3D-simulated mazes is feasible for studying neural correlates of olfactory and visual memory performance. Copyright © 2016 Elsevier Inc. All rights reserved.

Ageing and spatial reversal learning in humans: findings from a virtual water maze.

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Schoenfeld, R; Foreman, N; Leplow, B

2014-08-15

Deterioration in spatial memory with normal ageing is well accepted. Animal research has shown spatial reversal learning to be most vulnerable to pathological changes in the brain, but this has never been tested in humans. We studied ninety participants (52% females, 20-80 yrs) in a virtual water maze with a reversal learning procedure. Neuropsychological functioning, mood and personality were assessed to control moderator effects. For data analysis, participants were subdivided post hoc into groups aged 20-24, 25-34, 35-44, 45-64 and 65-80 yrs. Initial spatial learning occurred in all age groups but 65-80-yrs-olds never reached the level of younger participants. When tested for delayed recall of spatial memory, younger people frequented the target area but those over 65 yrs did not. In spatial reversal learning, age groups over 45 yrs were deficient and the 65-80-yrs-olds showed no evidence of reversal. Spatial measures were associated with neuropsychological functioning. Extraversion and measures of depression moderated the age effect on the learning index with older introverted and non-depressed individuals showing better results. Measures of anxiety moderated the age effect on reversal learning with older people having higher anxiety scores showing a preserved reversal learning capability. Results confirmed age to be a major factor in spatial tasks but further showed neuropsychological functioning, psycho-affective determinants and personality traits to be significant predictors of individual differences. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Identifying the appropriate time for deep brain stimulation to achieve spatial memory improvement on the Morris water maze.

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Jeong, Da Un; Lee, Jihyeon; Chang, Won Seok; Chang, Jin Woo

2017-03-07

The possibility of using deep brain stimulation (DBS) for memory enhancement has recently been reported, but the precise underlying mechanisms of its effects remain unknown. Our previous study suggested that spatial memory improvement by medial septum (MS)-DBS may be associated with cholinergic regulation and neurogenesis. However, the affected stage of memory could not be distinguished because the stimulation was delivered during the execution of all memory processes. Therefore, this study was performed to determine the stage of memory affected by MS-DBS. Rats were administered 192 IgG-saporin to lesion cholinergic neurons. Stimulation was delivered at different times in different groups of rats: 5 days before the Morris water maze test (pre-stimulation), 5 days during the training phase of the Morris water maze test (training-stimulation), and 2 h before the Morris water maze probe test (probe-stimulation). A fourth group of rats was lesioned but received no stimulation. These four groups were compared with a normal (control) group. The most effective memory restoration occurred in the pre-stimulation group. Moreover, the pre-stimulation group exhibited better recall of the platform position than the other stimulation groups. An increase in the level of brain derived neurotrophic factor (BDNF) was observed in the pre-stimulation group; this increase was maintained for 1 week. However, acetylcholinesterase activity in the pre-stimulation group was not significantly different from the lesion group. Memory impairment due to cholinergic denervation can be improved by DBS. The improvement is significantly correlated with the up-regulation of BDNF expression and neurogenesis. Based on the results of this study, the use of MS-DBS during the early stage of disease may restore spatial memory impairment.

Dizocilpine (MK-801) impairs learning in the active place avoidance task but has no effect on the performance during task/context alternation.

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Vojtechova, Iveta; Petrasek, Tomas; Hatalova, Hana; Pistikova, Adela; Vales, Karel; Stuchlik, Ales

2016-05-15

The prevention of engram interference, pattern separation, flexibility, cognitive coordination and spatial navigation are usually studied separately at the behavioral level. Impairment in executive functions is often observed in patients suffering from schizophrenia. We have designed a protocol for assessing these functions all together as behavioral separation. This protocol is based on alternated or sequential training in two tasks testing different hippocampal functions (the Morris water maze and active place avoidance), and alternated or sequential training in two similar environments of the active place avoidance task. In Experiment 1, we tested, in adult rats, whether the performance in two different spatial tasks was affected by their order in sequential learning, or by their day-to-day alternation. In Experiment 2, rats learned to solve the active place avoidance task in two environments either alternately or sequentially. We found that rats are able to acquire both tasks and to discriminate both similar contexts without obvious problems regardless of the order or the alternation. We used two groups of rats, controls and a rat model of psychosis induced by a subchronic intraperitoneal application of 0.08mg/kg of dizocilpine (MK-801), a non-competitive antagonist of NMDA receptors. Dizocilpine had no selective effect on parallel/sequential learning of tasks/contexts. However, it caused hyperlocomotion and a significant deficit in learning in the active place avoidance task regardless of the task alternation. Cognitive coordination tested by this task is probably more sensitive to dizocilpine than spatial orientation because no hyperactivity or learning impairment was observed in the Morris water maze. Copyright © 2016 Elsevier B.V. All rights reserved.

The ampakine, Org 26576, bolsters early spatial reference learning and retrieval in the Morris water maze: a subchronic, dose-ranging study in rats.

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Hamlyn, Eugene; Brand, Linda; Shahid, Mohammed; Harvey, Brian H

2009-10-01

Ampakines have shown beneficial effects on cognition in selected animal models of learning. However, their ability to modify long-term spatial memory tasks has not been studied yet. This would lend credence to their possible value in treating disorders of cognition. We evaluated the actions of subchronic Org 26576 administration on spatial reference memory performance in the 5-day Morris water maze task in male Sprague-Dawley rats, at doses of 1, 3 and 10 mg/kg twice daily through intraperitoneal injection over 12 days. Org 26576 exerted a dose and time-dependent effect on spatial learning, with dosages of 3 and 10 mg/kg significantly enhancing acquisition on day 1. Globally, escape latency decreased significantly as the training days progressed in the saline and Org 26576-treated groups, indicating that significant and equal learning had taken place over the learning period. However, at the end of the learning period, all doses of Org 26576 significantly improved spatial memory storage/retrieval without confounding effects in the cued version of the task. Org 26576 offers early phase spatial memory benefits in rats, but particularly enhances search accuracy during reference memory retrieval. These results support its possible utility in treating disorders characterized by deficits in cognitive performance.

Navigation using sensory substitution in real and virtual mazes.

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Chebat, Daniel-Robert; Maidenbaum, Shachar; Amedi, Amir

2015-01-01

Under certain specific conditions people who are blind have a perception of space that is equivalent to that of sighted individuals. However, in most cases their spatial perception is impaired. Is this simply due to their current lack of access to visual information or does the lack of visual information throughout development prevent the proper integration of the neural systems underlying spatial cognition? Sensory Substitution devices (SSDs) can transfer visual information via other senses and provide a unique tool to examine this question. We hypothesize that the use of our SSD (The EyeCane: a device that translates distance information into sounds and vibrations) can enable blind people to attain a similar performance level as the sighted in a spatial navigation task. We gave fifty-six participants training with the EyeCane. They navigated in real life-size mazes using the EyeCane SSD and in virtual renditions of the same mazes using a virtual-EyeCane. The participants were divided into four groups according to visual experience: congenitally blind, low vision & late blind, blindfolded sighted and sighted visual controls. We found that with the EyeCane participants made fewer errors in the maze, had fewer collisions, and completed the maze in less time on the last session compared to the first. By the third session, participants improved to the point where individual trials were no longer significantly different from the initial performance of the sighted visual group in terms of errors, time and collision.

Changes in Search Path Complexity and Length During Learning of a Virtual Water Maze: Age Differences and Differential Associations with Hippocampal Subfield Volumes.

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Daugherty, Ana M; Bender, Andrew R; Yuan, Peng; Raz, Naftali

2016-06-01

Impairment of hippocampus-dependent cognitive processes has been proposed to underlie age-related deficits in navigation. Animal studies suggest a differential role of hippocampal subfields in various aspects of navigation, but that hypothesis has not been tested in humans. In this study, we examined the association between volume of hippocampal subfields and age differences in virtual spatial navigation. In a sample of 65 healthy adults (age 19-75 years), advanced age was associated with a slower rate of improvement operationalized as shortening of the search path over 25 learning trials on a virtual Morris water maze task. The deficits were partially explained by greater complexity of older adults' search paths. Larger subiculum and entorhinal cortex volumes were associated with a faster decrease in search path complexity, which in turn explained faster shortening of search distance. Larger Cornu Ammonis (CA)1-2 volume was associated with faster distance shortening, but not in path complexity reduction. Age differences in regional volumes collectively accounted for 23% of the age-related variance in navigation learning. Independent of subfield volumes, advanced age was associated with poorer performance across all trials, even after reaching the asymptote. Thus, subiculum and CA1-2 volumes were associated with speed of acquisition, but not magnitude of gains in virtual maze navigation. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Decreased proliferation in the adult rat hippocampus after exposure to the Morris water maze and its reversal by fluoxetine

Czech Academy of Sciences Publication Activity Database

Náměstková, Kateřina; Šimonová, Zuzana; Syková, Eva

2005-01-01

Roč. 163, č. 1 (2005), s. 26-32 ISSN 0166-4328 R&D Projects: GA ČR(CZ) GA304/03/1189; GA MŠk(CZ) LN00A065 Institutional research plan: CEZ:AV0Z50390512 Keywords : Antidepressant * Water maze * Neurogenesis Subject RIV: FJ - Surgery incl. Transplants Impact factor: 2.865, year: 2005

Navigation using sensory substitution in real and virtual mazes.

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Daniel-Robert Chebat

Full Text Available Under certain specific conditions people who are blind have a perception of space that is equivalent to that of sighted individuals. However, in most cases their spatial perception is impaired. Is this simply due to their current lack of access to visual information or does the lack of visual information throughout development prevent the proper integration of the neural systems underlying spatial cognition? Sensory Substitution devices (SSDs can transfer visual information via other senses and provide a unique tool to examine this question. We hypothesize that the use of our SSD (The EyeCane: a device that translates distance information into sounds and vibrations can enable blind people to attain a similar performance level as the sighted in a spatial navigation task. We gave fifty-six participants training with the EyeCane. They navigated in real life-size mazes using the EyeCane SSD and in virtual renditions of the same mazes using a virtual-EyeCane. The participants were divided into four groups according to visual experience: congenitally blind, low vision & late blind, blindfolded sighted and sighted visual controls. We found that with the EyeCane participants made fewer errors in the maze, had fewer collisions, and completed the maze in less time on the last session compared to the first. By the third session, participants improved to the point where individual trials were no longer significantly different from the initial performance of the sighted visual group in terms of errors, time and collision.

Spatial memory deficits in a virtual reality eight-arm radial maze in schizophrenia.

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Spieker, Elena A; Astur, Robert S; West, Jeffrey T; Griego, Jacqueline A; Rowland, Laura M

2012-03-01

Learning and memory impairments are present in schizophrenia (SZ) throughout the illness course and predict psychosocial function. Abnormalities in prefrontal and hippocampal function are thought to contribute to SZ deficits. The radial arm maze (RAM) is a test of spatial learning and memory in rodents that relies on intact prefrontal and hippocampal function. The goal of the present study was to investigate spatial learning in SZ using a virtual RAM. Thirty-three subjects with SZ and thirty-nine healthy controls (HC) performed ten trials of a virtual RAM task. Subjects attempted to learn to retrieve four rewards each located in separate arms. As expected, subjects with SZ used more time and traveled more distance to retrieve rewards, made more reference (RM) and working memory (WM) errors, and retrieved fewer rewards than HC. It is important to note that the SZ group did learn but did not reach the level of HC. Whereas RM errors decreased across trials in the SZ group, WM errors did not. There were no significant relationships between psychiatric symptom severity and maze performance. To our knowledge, use of a virtual 8-arm radial maze task in SZ to assess spatial learning is novel. Impaired virtual RAM performance in SZ is consistent with studies that examined RAM performance in animal models of SZ. Results provide further support for compromised prefrontal and hippocampal function underlying WM and RM deficits in SZ. The virtual RAM task could help bridge preclinical and clinical research for testing novel drug treatments of SZ. Copyright © 2011 Elsevier B.V. All rights reserved.

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

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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…

Electric Current Solves Mazes

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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:…

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

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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…

Progressive paradoxical sleep deprivation impairs partial memory following learning tasks in rats

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Chunmin Zhu; Xiangrong Yao; Weisheng Zhang; Yanfeng Song; Yiping Hou

2008-01-01

BACKGROUND: Complex learning tasks result in a greater number of paradoxical sleep phases, which can improve memory. The effect of paradoxical sleep deprivation, induced by "flower pot" technique, on spatial reference memory and working memory require further research. OBJECTIVE: To observe the effect of progressive paradoxical sleep deprivation in rats, subsequent to learning, on memory using the Morris Water Maze. DESIGN, TIME AND SETTING: Controlled observation experiment. The experiment was performed at the Laboratory of Neurobiology, Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Lanzhou University from December 2006 to October 2007. MATERIALS: Twenty-eight, male, Wistar rats, 3-4 months old, were provided by the Experimental Animal Center of Lanzhou University. The Morris Water Maze and behavioral analyses system was purchased from Genheart Company, Beijing, China. METHODS: All animals, according to a random digits table, were randomly divided into paradoxical sleep deprivation, tank control, and home cage control groups. Paradoxical sleep deprivation was induced by the "flower pot" technique for 72 hours, housing the rats on small platforms over water. Rats in the "tank control" and "home cage control" groups were housed either in a tank with large platforms over the water or in normal cages without paradoxical sleep deprivation. MAIN OUTCOME MEASURES: Morris Water Maze was employed for task learning and spatial memory testing. Rats in all groups were placed at six random starting points each day for four consecutive days. Each placement was repeated for two trials; the first trial represented reference memory and the second working memory. Rats in the first trial were allowed to locate the submerged platform within 120 seconds. Data, including swimming distance, escape latency, swimming velocity, percentage of time in correct quarter, and memory scores were recorded and analyzed automatically by behavioral analyses

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

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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…

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

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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

Computer task performance by subjects with Duchenne muscular dystrophy.

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Malheiros, Silvia Regina Pinheiro; da Silva, Talita Dias; Favero, Francis Meire; de Abreu, Luiz Carlos; Fregni, Felipe; Ribeiro, Denise Cardoso; de Mello Monteiro, Carlos Bandeira

2016-01-01

Two specific objectives were established to quantify computer task performance among people with Duchenne muscular dystrophy (DMD). First, we compared simple computational task performance between subjects with DMD and age-matched typically developing (TD) subjects. Second, we examined correlations between the ability of subjects with DMD to learn the computational task and their motor functionality, age, and initial task performance. The study included 84 individuals (42 with DMD, mean age of 18±5.5 years, and 42 age-matched controls). They executed a computer maze task; all participants performed the acquisition (20 attempts) and retention (five attempts) phases, repeating the same maze. A different maze was used to verify transfer performance (five attempts). The Motor Function Measure Scale was applied, and the results were compared with maze task performance. In the acquisition phase, a significant decrease was found in movement time (MT) between the first and last acquisition block, but only for the DMD group. For the DMD group, MT during transfer was shorter than during the first acquisition block, indicating improvement from the first acquisition block to transfer. In addition, the TD group showed shorter MT than the DMD group across the study. DMD participants improved their performance after practicing a computational task; however, the difference in MT was present in all attempts among DMD and control subjects. Computational task improvement was positively influenced by the initial performance of individuals with DMD. In turn, the initial performance was influenced by their distal functionality but not their age or overall functionality.

Glow discharge based device for solving mazes

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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.

MK-801 and memantine act differently on short-term memory tested with different time-intervals in the Morris water maze test

Czech Academy of Sciences Publication Activity Database

Duda, W.; Wesierska, M.; Ostaszewski, P.; Valeš, Karel; Nekovářová, Tereza; Stuchlík, Aleš

2016-01-01

Roč. 311, Sep 15 (2016), s. 15-23 ISSN 0166-4328 R&D Projects: GA MŠk(CZ) LH14053; GA ČR(CZ) GA14-03627S Institutional support: RVO:67985823 Keywords : short-term memory * spatial working memory * memantine * dizocilpine * Morris water maze Subject RIV: FH - Neurology Impact factor: 3.002, year: 2016

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

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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.

Similar reliability and equivalent performance of female and male mice in the open field and water‐maze place navigation task

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Fritz, Ann‐Kristina; Amrein, Irmgard

2017-01-01

Although most nervous system diseases affect women and men differentially, most behavioral studies using mouse models do not include subjects of both sexes. Many researchers worry that data of female mice may be unreliable due to the estrous cycle. Here, we retrospectively evaluated sex effects on coefficient of variation (CV) in 5,311 mice which had performed the same place navigation protocol in the water‐maze and in 4,554 mice tested in the same open field arena. Confidence intervals for Cohen's d as measure of effect size were computed and tested for equivalence with 0.2 as equivalence margin. Despite the large sample size, only few behavioral parameters showed a significant sex effect on CV. Confidence intervals of effect size indicated that CV was either equivalent or showed a small sex difference at most, accounting for less than 2% of total group to group variation of CV. While female mice were potentially slightly more variable in water‐maze acquisition and in the open field, males tended to perform less reliably in the water‐maze probe trial. In addition to evaluating variability, we also directly compared mean performance of female and male mice and found them to be equivalent in both water‐maze place navigation and open field exploration. Our data confirm and extend other large scale studies in demonstrating that including female mice in experiments does not cause a relevant increase of data variability. Our results make a strong case for including mice of both sexes whenever open field or water‐maze are used in preclinical research. PMID:28654717

Dizocilpine (MK-801) impairs learning in the active place avoidance task but has no effect on the performance during task/context alternation

Czech Academy of Sciences Publication Activity Database

Vojtěchová, Iveta; Petrásek, Tomáš; Hatalová, Hana; Pištíková, Adéla; Valeš, Karel; Stuchlík, Aleš

2016-01-01

Roč. 305, May 15 (2016), s. 247-257 ISSN 0166-4328 R&D Projects: GA ČR(CZ) GA14-03627S Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M200111204 Institutional support: RVO:67985823 Keywords : task alternation * context alternation * active place avoidance * Morris water maze * Dizocilpine * schizophrenia Subject RIV: FH - Neurology Impact factor: 3.002, year: 2016

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

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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…

Middle-aged human apoE4 targeted-replacement mice show retention deficits on a wide range of spatial memory tasks.

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Bour, Alexandra; Grootendorst, Jeannette; Vogel, Elise; Kelche, Christian; Dodart, Jean-Cosme; Bales, Kelly; Moreau, Pierre-Henri; Sullivan, Patrick M; Mathis, Chantal

2008-11-21

Apolipoprotein (apo) E4, one of three human apoE (h-apoE) isoforms, has been identified as a major genetic risk factor for Alzheimer's disease and for cognitive deficits associated with aging. However, the biological mechanisms involving apoE in learning and memory processes are unclear. A potential isoform-dependent role of apoE in cognitive processes was studied in human apoE targeted-replacement (TR) mice. These mice express either the human apoE3 or apoE4 gene under the control of endogenous murine apoE regulatory sequences, resulting in physiological expression of h-apoE in both a temporal and spatial pattern similar to humans. Male and female apoE3-TR, apoE4-TR, apoE-knockout and C57BL/6J mice (15-18 months) were tested with spatial memory and avoidance conditioning tasks. Compared to apoE3-TR mice, spatial memory in female apoE4-TR mice was impaired based on their poor performances in; (i) the probe test of the water-maze reference memory task, (ii) the water-maze working memory task and (iii) an active avoidance Y-maze task. Retention performance on a passive avoidance task was also impaired in apoE4-TR mice, but not in other genotypes. These deficits in both spatial and avoidance memory tasks may be related to the anatomical and functional abnormalities previously reported in the hippocampus and the amygdala of apoE4-TR mice. We conclude that the apoE4-TR mice provide an excellent model for understanding the mechanisms underlying apoE4-dependent susceptibility to cognitive decline.

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

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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.

Immediate response strategy and shift to place strategy in submerged T-maze.

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Asem, Judith S A; Holland, Peter C

2013-12-01

A considerable amount of research has demonstrated that animals can use different strategies when learning about, and navigating within, their environment. Since the influential research of Packard and McGaugh (1996), it has been widely accepted that, early in learning, rats use a flexible dorsal hippocampal-dependent place strategy. As learning progresses, they switch to a less effortful and more automatic dorsolateral caudate-dependent response strategy. However, supporting literature is dominated by the use of appetitively motivated tasks, using food reward. Because motivation often plays a crucial role in guiding learning, memory, and behavior, we examined spatial learning strategies of rats in an escape-motivated submerged T-maze. In Experiment 1, we observed rapid learning and the opposite pattern as that reported in appetitively motivated tasks. Rats exhibited a response strategy early in learning before switching to a place strategy, which persisted over extensive training. In Experiment 2, we replicated Packard and McGaugh's (1996) observations, using the apparatus and procedures as in Experiment 1, but with food reward instead of water escape. Mechanisms for, and implications of, this motivational modulation of spatial learning strategy are considered.

Stable, Long-Term, Spatial Memory in Young and Aged Rats Achieved with a One Day Morris Water Maze Training Protocol

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Barrientos, Ruth M.; Kitt, Meagan M.; D'Angelo, Heather M.; Watkins, Linda R.; Rudy, Jerry W.; Maier, Steven F.

2016-01-01

Here, we present data demonstrating that a 1 d Morris water maze training protocol is effective at producing stable, long-term spatial memory in both young (3 mo old) and aged (24 mo old) F344xBN rats. Four trials in each of four sessions separated by a 2.5 h ISI produced robust selective search for the platform 1 and 4 d after training, in both…

Little and often? Maintaining continued performance in an automated T-maze for mice.

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Gaskill, Brianna N; Lucas, Jeffrey R; Pajor, Edmond A; Garner, Joseph P

2011-02-01

Operant and maze tasks in mice are limited by the small number of trials possible in a session before mice lose motivation. We hypothesized that by manipulating reward size and session length, motivation, and hence performance, would be maintained in an automated T-maze. We predicted that larger rewards and shorter sessions would improve acquisition; and smaller rewards and shorter sessions would maintain higher and less variable performance. Eighteen C57BL/6J mice (9 per sex) acquired (criterion 8/10 correct) and performed a spatial discrimination, with one of 3 reward sizes (.02, .04, or .08 g) and one of 3 session schedules (15, 30, or 45 min sessions). Each mouse had a total of 360 min of access to the maze per night, for two nights, and averaged 190 trials. Analysis used split-plot GLM with contrasts testing for linear effects. Acquisition of the discrimination was unaffected by reward size or session length/interval. After-criterion average performance improved as reward size decreased. After-criterion variability in performance was also affected. Variability increased as reward size increased. Session length/interval did not affect any outcome. We conclude that an automated maze, with suitable reward sizes, can sustain performance with low variability, at 5-10 times faster than traditional methods. Copyright © 2011 Elsevier B.V. All rights reserved.

Deficits in water maze performance and oxidative stress in the hippocampus and striatum induced by extremely low frequency magnetic field exposure.

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Yonghua Cui

Full Text Available The exposures to extremely low frequency magnetic field (ELF-MF in our environment have dramatically increased. Epidemiological studies suggest that there is a possible association between ELF-MF exposure and increased risks of cardiovascular disease, cancers and neurodegenerative disorders. Animal studies show that ELF-MF exposure may interfere with the activity of brain cells, generate behavioral and cognitive disturbances, and produce deficits in attention, perception and spatial learning. Although, many research efforts have been focused on the interaction between ELF-MF exposure and the central nervous system, the mechanism of interaction is still unknown. In this study, we examined the effects of ELF-MF exposure on learning in mice using two water maze tasks and on some parameters indicative of oxidative stress in the hippocampus and striatum. We found that ELF-MF exposure (1 mT, 50 Hz induced serious oxidative stress in the hippocampus and striatum and impaired hippocampal-dependent spatial learning and striatum-dependent habit learning. This study provides evidence for the association between the impairment of learning and the oxidative stress in hippocampus and striatum induced by ELF-MF exposure.

Hamsters' (Mesocricetus auratus) memory in a radial maze analog: the role of spatial versus olfactory cues.

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Tonneau, François; Cabrera, Felipe; Corujo, Alejandro

2012-02-01

The golden hamster's (Mesocricetus auratus) performance on radial maze tasks has not been studied a lot. Here we report the results of a spatial memory task that involved eight food stations equidistant from the center of a circular platform. Each of six male hamsters depleted the food stations along successive choices. After each choice and a 5-s retention delay, the hamster was brought back to the center of the platform for the next choice opportunity. When only one baited station was left, the platform was rotated to evaluate whether olfactory traces guided hamsters' choices. Results showed that despite the retention delay hamsters performed above chance in searching for food. The choice distributions observed during the rotation probes were consistent with spatial memory and could be explained without assuming guidance by olfactory cues. The radial maze analog we devised could be useful in furthering the study of spatial memory in hamsters.

Problem-solving in English through business mazes

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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.

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

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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

Effects of zolpidem on sedation, anxiety, and memory in the plus-maze discriminative avoidance task.

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Zanin, Karina A; Patti, Camilla L; Sanday, Leandro; Fernandes-Santos, Luciano; Oliveira, Larissa C; Poyares, Dalva; Tufik, Sergio; Frussa-Filho, Roberto

2013-04-01

Zolpidem (Zolp), a hypnotic drug prescribed to treat insomnia, may have negative effects on memory, but reports are inconsistent. We examined the effects of acute doses of Zolp (2, 5, or 10 mg/kg, i.p.) on memory formation (learning, consolidation, and retrieval) using the plus-maze discriminative avoidance task. Mice were acutely treated with Zolp 30 min before training or testing. In addition, the effects of Zolp and midazolam (Mid; a classic benzodiazepine) on consolidation at different time points were examined. The possible role of state dependency was investigated using combined pre-training and pre-test treatments. Zolp produced a dose-dependent sedative effect, without modifying anxiety-like behavior. The pre-training administration of 5 or 10 mg/kg resulted in retention deficits. When administered immediately after training or before testing, memory was preserved. Zolp post-training administration (2 or 3 h) impaired subsequent memory. There was no participation of state dependency phenomenon in the amnestic effects of Zolp. Similar to Zolp, Mid impaired memory consolidation when administered 1 h after training. Amnestic effects occurred when Zolp was administered either before or 2-3 h after training. These memory deficits are not related to state dependency. Moreover, Zolp did not impair memory retrieval. Notably, the memory-impairing effects of Zolp are similar to those of Mid, with the exception of the time point at which the drug can modify consolidation. Finally, the memory effects were unrelated to sedation or anxiolysis.

Path Complexity in Virtual Water Maze Navigation: Differential Associations with Age, Sex, and Regional Brain Volume.

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Daugherty, Ana M; Yuan, Peng; Dahle, Cheryl L; Bender, Andrew R; Yang, Yiqin; Raz, Naftali

2015-09-01

Studies of human navigation in virtual maze environments have consistently linked advanced age with greater distance traveled between the start and the goal and longer duration of the search. Observations of search path geometry suggest that routes taken by older adults may be unnecessarily complex and that excessive path complexity may be an indicator of cognitive difficulties experienced by older navigators. In a sample of healthy adults, we quantify search path complexity in a virtual Morris water maze with a novel method based on fractal dimensionality. In a two-level hierarchical linear model, we estimated improvement in navigation performance across trials by a decline in route length, shortening of search time, and reduction in fractal dimensionality of the path. While replicating commonly reported age and sex differences in time and distance indices, a reduction in fractal dimension of the path accounted for improvement across trials, independent of age or sex. The volumes of brain regions associated with the establishment of cognitive maps (parahippocampal gyrus and hippocampus) were related to path dimensionality, but not to the total distance and time. Thus, fractal dimensionality of a navigational path may present a useful complementary method of quantifying performance in navigation. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

A Maze Game on Android Using Growing Tree Method

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Hendrawan, Y. F.

2018-01-01

A maze is a type of puzzle games where a player moves in complex and branched passages to find a particular target or location. One method to create a maze is the Growing Tree method. The method creates a tree that has branches which are the paths of a maze. This research explored three types of Growing Tree method implementations for maze generation on Android mobile devices. The layouts produced could be played in first and third-person perspectives. The experiment results showed that it took 17.3 seconds on average to generate 20 cells x 20 cells dynamic maze layouts.

Applications of the Morris water maze in translational traumatic brain injury research.

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Tucker, Laura B; Velosky, Alexander G; McCabe, Joseph T

2018-05-01

Acquired traumatic brain injury (TBI) is frequently accompanied by persistent cognitive symptoms, including executive function disruptions and memory deficits. The Morris Water Maze (MWM) is the most widely-employed laboratory behavioral test for assessing cognitive deficits in rodents after experimental TBI. Numerous protocols exist for performing the test, which has shown great robustness in detecting learning and memory deficits in rodents after infliction of TBI. We review applications of the MWM for the study of cognitive deficits following TBI in pre-clinical studies, describing multiple ways in which the test can be employed to examine specific aspects of learning and memory. Emphasis is placed on dependent measures that are available and important controls that must be considered in the context of TBI. Finally, caution is given regarding interpretation of deficits as being indicative of dysfunction of a single brain region (hippocampus), as experimental models of TBI most often result in more diffuse damage that disrupts multiple neural pathways and larger functional networks that participate in complex behaviors required in MWM performance. Published by Elsevier Ltd.

Long-term effects of immunotoxic cholinergic lesions in the septum on acquisition of the cone-field task and noncognitive measures in rats

NARCIS (Netherlands)

Staay, van der F.J.; Bouger, P.; Lehmann, O.; Lazarus, C.; Cosquer, B.; Koenig, J.; Stump, V.; Cassel, J.C.

2006-01-01

In rats, nonspecific mechanical or neurotoxic lesions of the septum impair spatial memory in, e.g., Morris water- and radial-maze tasks. Unfortunately, the lack of specificity of such lesions limits inferences about the role of the cholinergic hippocampal projections in spatial cognition. We

Food restriction affects Y-maze spatial recognition memory in developing mice.

Science.gov (United States)

Fu, Yu; Chen, Yanmei; Li, Liane; Wang, Yumei; Kong, Xiangyang; Wang, Jianhong

2017-08-01

The ambiguous effects of food restriction (FR) on cognition in rodents have been mostly explored in the aged brain by a variety of paradigms, in which either rewards or punishments are involved. This study aims to examine the effects of chronic and acute FR with varying intensities on spatial recognition memory in developing mice. We have used a Y-maze task that is based on the innate tendency of rodents to explore novel environments. In chronic FR, mice had 70-30% chow of control for seven weeks. In acute FR, mice were food restricted for 12-48h before the tests. We found that chronic FR had no effect on the preference of mice for novelty in the Y-maze, but severe FR (50-30% of control) caused impairment on spatial recognition memory. The impairment significantly correlated with the slow weight growth induced by FR. Acute FR also did not affect the novelty preference of mice, but either improved or impaired the memory retention. These data suggest chronic FR impairs Y-maze spatial recognition memory in developing mice depending on FR intensity and individual tolerability of the FR. Moreover, acute FR exerts diverse effects on the memory, either positive or negative. Our findings have revealed new insights on the effects of FR on spatial recognition memory in developing animals. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.

Negative effects of chronic oral chlorpromazine and olanzapine treatment on the performance of tasks designed to assess spatial learning and working memory in rats.

Science.gov (United States)

Terry, A V; Warner, S E; Vandenhuerk, L; Pillai, A; Mahadik, S P; Zhang, G; Bartlett, M G

2008-10-28

Learning potential and memory capacity are factors that strongly predict the level of rehabilitation and the long-term functional outcome in patients with schizophrenia. Unfortunately, however, the effects of antipsychotic drugs (i.e. the primary treatments for schizophrenia) on these components of cognition are unclear, particularly when they are administered chronically (i.e. a standard clinical practice). In this rodent study we evaluated the effects of different time periods (ranging from 2 weeks to 6 months) of oral treatment with the first generation antipsychotic chlorpromazine (10.0 mg/kg/day), or the second generation antipsychotic olanzapine (10.0 mg/kg/day) on the repeated acquisition of a water maze task (i.e. a method of assessing spatial learning potential in a repeated testing format). We assessed locomotor function (in an open field) and employed a radial arm maze (RAM) task to assess antipsychotic effects (5.0 and 10.0 mg/kg/day doses) on spatial working memory during the treatment period between 15 days and 2 months. Finally, we conducted experiments using liquid chromatography/tandem mass spectrometry (LC-MS/MS) to evaluate the therapeutic relevance of our method of drug delivery (oral administration in drinking water). In the water maze experiments, both antipsychotics were associated with impairments in acquisition in the earlier test sessions that could eventually be overcome with repeated testing while olanzapine also impaired retention in probe trials. Both antipsychotics were also associated with impairments in delayed non-match-to-position trials in the RAM and some impairments of motor function (especially in the case of olanzapine) as indicated by slightly reduced swim speeds in the water maze and decreased activity in some components of the open field assessment. Finally, LC-MS/MS studies indicated that the method of antipsychotic administration generated clinically relevant plasma levels in the rat. These animal data indicate that

Unilateral robotic hybrid mini-maze: a novel experimental approach.

Science.gov (United States)

Moslemi, Mohammad; Rawashdeh, Badi; Meyer, Mark; Nguyen, Duy; Poston, Robert; Gharagozloo, Farid

2016-03-01

A complete Cox maze IV procedure is difficult to accomplish using current endoscopic and minimally invasive techniques. These techniques are hampered by inability to adequately dissect the posterior structures of the heart and place all necessary lesions. We present a novel approach, using robotic technology, that achieves placement of all the lesions of the complete maze procedure. In three cadaveric human models, the technical feasibility of using robotic instruments through the right chest to dissect the posterior structures of the heart and place all Cox maze lesions was performed. The entire posterior aspect of the heart was dissected in the cadaveric model facilitating successful placement of all Cox maze IV lesions with robotic assistance through minimally invasive incisions. The robotic Cox maze IV procedure through the novel right thoracic approach is feasible. This obviates the need for sternotomy and avoids the associated morbidity of the conventional Cox-maze procedure. Copyright © 2015 John Wiley & Sons, Ltd.

Distinction between epigenic and hypogenic maze caves

Science.gov (United States)

Palmer, Arthur N.

2011-11-01

Certain caves formed by dissolution of bedrock have maze patterns composed of closed loops in which many intersecting fractures or pores have enlarged simultaneously. Their origin can be epigenic (by shallow circulation of meteoric groundwater) or hypogenic (by rising groundwater or production of deep-seated solutional aggressiveness). Epigenic mazes form by diffuse infiltration through a permeable insoluble caprock or by floodwater supplied by sinking streams. Most hypogenic caves involve deep sources of aggressiveness. Transverse hypogenic cave origin is a recently proposed concept in which groundwater of mainly meteoric origin rises across strata in the distal portions of large flow systems, to form mazes in soluble rock sandwiched between permeable but insoluble strata. The distinction between maze types is debated and is usually based on examination of diagnostic cave features and relation of caves to their regional setting. In this paper, the principles of mass transfer are applied to clarify the limits of each model, to show how cave origin is related to groundwater discharge, dissolution rate, and time. The results show that diffuse infiltration and floodwater can each form maze caves at geologically feasible rates (typically within 500 ka). Transverse hypogenic mazes in limestone, to enlarge significantly within 1 Ma, require an unusually high permeability of the non-carbonate beds (generally ≥ 10-4 cm/s), large discharge, and calcite saturation no greater than 90%, which is rare in deep diffuse flow in sedimentary rocks. Deep sources of aggressiveness are usually required. The origin of caves by transverse hypogenic flow is much more favorable in evaporite rocks than in carbonate rocks.

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.

Nogo-A downregulation impairs place avoidance in the Carousel maze but not spatial memory in the Morris water maze

Czech Academy of Sciences Publication Activity Database

Petrásek, Tomáš; Prokopová, Iva; Bahník, Štěpán; Schönig, K.; Berger, S.; Valeš, Karel; Tews, B.; Schwab, M. E.; Bartsch, D.; Stuchlík, Aleš

2014-01-01

Roč. 107, Jan 2014 (2014), s. 42-49 ISSN 1074-7427 R&D Projects: GA ČR(CZ) GCP303/10/J032; GA ČR(CZ) GBP304/12/G069; GA MZd(CZ) NT13386; GA ČR(CZ) GA14-03627S Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M200111204; Univerzita Karlova(CZ) 365911 Institutional support: RVO:67985823 Keywords : Nogo-A * spatial navigation * cognitive coordination * spatial mazes * transgenic rat model Subject RIV: FH - Neurology Impact factor: 3.652, year: 2014

The scopolamine-reversal paradigm in rats and monkeys: the importance of computer-assisted operant-conditioning memory tasks for screening drug candidates.

Science.gov (United States)

Buccafusco, Jerry J; Terry, Alvin V; Webster, Scott J; Martin, Daniel; Hohnadel, Elizabeth J; Bouchard, Kristy A; Warner, Samantha E

2008-08-01

The scopolamine-reversal model is enjoying a resurgence of interest in clinical studies as a reversible pharmacological model for Alzheimer's disease (AD). The cognitive impairment associated with scopolamine is similar to that in AD. The scopolamine model is not simply a cholinergic model, as it can be reversed by drugs that are noncholinergic cognition-enhancing agents. The objective of the study was to determine relevance of computer-assisted operant-conditioning tasks in the scopolamine-reversal model in rats and monkeys. Rats were evaluated for their acquisition of a spatial reference memory task in the Morris water maze. A separate cohort was proficient in performance of an automated delayed stimulus discrimination task (DSDT). Rhesus monkeys were proficient in the performance of an automated delayed matching-to-sample task (DMTS). The AD drug donepezil was evaluated for its ability to reverse the decrements in accuracy induced by scopolamine administration in all three tasks. In the DSDT and DMTS tasks, the effects of donepezil were delay (retention interval)-dependent, affecting primarily short delay trials. Donepezil produced significant but partial reversals of the scopolamine-induced impairment in task accuracies after 2 mg/kg in the water maze, after 1 mg/kg in the DSDT, and after 50 microg/kg in the DMTS task. The two operant-conditioning tasks (DSDT and DMTS) provided data most in keeping with those reported in clinical studies with these drugs. The model applied to nonhuman primates provides an excellent transitional model for new cognition-enhancing drugs before clinical trials.

The flexible use of multiple cue relationships in spatial navigation : A comparison of water maze performance following hippocampal, medial septal, prefrontal cortex, or posterior parietal cortex lesions

NARCIS (Netherlands)

Compton, DM; Griffith, HR; McDaniel, WF; Foster, RA; Davis, BK

Rats prepared with lesions of the prefrontal cortex, posterior parietal cortex, hippocampus, or medial septal area were tested for acquisition of a number of variations of the open-field water maze using a version of place learning assessment described by Eichenbaum, Stewart, and Morris (1991).

Social Observation Task in a Linear Maze for Rats.

Science.gov (United States)

Mou, Xiang; Ji, Daoyun

2017-07-05

Animals often learn through observing their conspecifics. However, the mechanisms of them obtaining useful knowledge during observation are beginning to be understood. This protocol describes a novel social observation task to test the 'local enhancement theory', which proposes that presence of social subjects in an environment facilitates one's understanding of the environments. By combining behavior test and in vivo electrophysiological recording, we found that social observation can facilitate the observer's spatial representation of an unexplored environment. The task protocol was published in Mou and Ji, 2016.

The VMAT-2 inhibitor tetrabenazine alters effort-related decision making as measured by the T-maze barrier choice task: reversal with the adenosine A2A antagonist MSX-3 and the catecholamine uptake blocker bupropion.

Science.gov (United States)

Yohn, Samantha E; Thompson, Christian; Randall, Patrick A; Lee, Christie A; Müller, Christa E; Baqi, Younis; Correa, Mercè; Salamone, John D

2015-04-01

Depressed people show effort-related motivational symptoms, such as anergia, retardation, lassitude, and fatigue. Animal tests can model these motivational symptoms, and the present studies characterized the effort-related effects of the vesicular monoamine transport (VMAT-2) inhibitor tetrabenazine. Tetrabenazine produces depressive symptoms in humans and, at low doses, preferentially depletes dopamine. The current studies investigated the effects of tetrabenazine on effort-based decision making using the T-maze barrier task. Rats were tested in a T-maze in which the choice arms of the maze contain different reinforcement densities, and under some conditions, a vertical barrier was placed in the high-density arm to provide an effort-related challenge. The first experiment assessed the effects of tetrabenazine under different maze conditions: a barrier in the arm with 4 food pellets and 2 pellets in the no barrier arm (4-2 barrier), 4 pellets in one arm and 2 pellets in the other with no barrier in either arm (no barrier), and 4 pellets in the barrier arm with no pellets in the other (4-0 barrier). Tetrabenazine (0.25-0.75 mg/kg IP) decreased selection of the high cost/high reward arm when the barrier was present, but had no effect on choice under the no barrier and 4-0 barrier conditions. The effects of tetrabenazine on barrier climbing in the 4-2 condition were reversed by the adenosine A2A antagonist MSX-3 and the catecholamine uptake inhibitor and antidepressant bupropion. These studies have implications for the development of animal models of the motivational symptoms of depression and other disorders.

Fos Protein Expression in Olfactory-Related Brain Areas after Learning and after Reactivation of a Slowly Acquired Olfactory Discrimination Task in the Rat

Science.gov (United States)

Roullet, Florence; Lienard, Fabienne; Datiche, Frederique; Cattarelli, Martine

2005-01-01

Fos protein immunodetection was used to investigate the neuronal activation elicited in some olfactory-related areas after either learning of an olfactory discrimination task or its reactivation 10 d later. Trained rats (T) progressively acquired the association between one odor of a pair and water-reward in a four-arm maze. Two groups of…

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

International Nuclear Information System (INIS)

Camplesi, M. Jr.; Bortoli, V.C. de; Paula Soares, V. de; Nogueira, R.L.; Zangrossi, H. Jr.

2012-01-01

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 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

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.

Utility of the Hebb-Williams Maze Paradigm for Translational Research in Fragile X Syndrome: A Direct Comparison of Mice and Humans.

Science.gov (United States)

Boutet, Isabelle; Collin, Charles A; MacLeod, Lindsey S; Messier, Claude; Holahan, Matthew R; Berry-Kravis, Elizabeth; Gandhi, Reno M; Kogan, Cary S

2018-01-01

To generate meaningful information, translational research must employ paradigms that allow extrapolation from animal models to humans. However, few studies have evaluated translational paradigms on the basis of defined validation criteria. We outline three criteria for validating translational paradigms. We then evaluate the Hebb-Williams maze paradigm (Hebb and Williams, 1946; Rabinovitch and Rosvold, 1951) on the basis of these criteria using Fragile X syndrome (FXS) as model disease. We focused on this paradigm because it allows direct comparison of humans and animals on tasks that are behaviorally equivalent (criterion #1) and because it measures spatial information processing, a cognitive domain for which FXS individuals and mice show impairments as compared to controls (criterion #2). We directly compared the performance of affected humans and mice across different experimental conditions and measures of behavior to identify which conditions produce comparable patterns of results in both species. Species differences were negligible for Mazes 2, 4, and 5 irrespective of the presence of visual cues, suggesting that these mazes could be used to measure spatial learning in both species. With regards to performance on the first trial, which reflects visuo-spatial problem solving, Mazes 5 and 9 without visual cues produced the most consistent results. We conclude that the Hebb-Williams mazes paradigm has the potential to be utilized in translational research to measure comparable cognitive functions in FXS humans and animals (criterion #3).

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 both hippocampus-dependent spatial learning and learning a new target location within a familiar environment: reversal learning. A 6-d protocol was divided into the initial spatial learning phase (3.5 d) immediately followed by the reversal phase (2.5 d). During the 6 h following four or 12 training trials/day of initial or reversal learning phases, REM sleep was eliminated and non-REM sleep left intact using the multiple inverted flowerpot method. Contrary to our hypotheses, REM sleep deprivation during four or 12 trials/day of initial spatial or reversal learning did not affect training performance. However, some probe trial measures indicated REM sleep-deprivation–associated impairment in initial spatial learning with four trials/day and enhancement of subsequent reversal learning. In naive animals, REM sleep deprivation during normal initial spatial learning was followed by a lack of preference for the subsequent reversal platform location during the probe. Our findings contradict reports that REM sleep is essential for spatial learning in the Morris water maze and newly reveal that short periods of REM sleep deprivation do not impair concurrent reversal learning. Effects on subsequent reversal learning are consistent with the idea that REM sleep serves the consolidation of incompletely learned items. PMID:21677190

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

Science.gov (United States)

Carelli, Laura; Rusconi, Maria Luisa; Scarabelli, Chiara; Stampatori, Chiara; Mattioli, Flavia; Riva, Giuseppe

2011-01-31

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. 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. 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. 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 demanding and sensitive to cognitive decline.Human-computer interaction

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

A comparison of the calculation methods of the maze shielding dose

International Nuclear Information System (INIS)

Li Wenqian; Li Junli; Li Pengyu; Tao Yinghua

2009-01-01

This paper gives a theoretical calculating method for the dose rate of the maze of the low-energy accelerators or high-energy accelerators, based on the NCRP report Nos.49, 51 and 151. The multi-legged maze of the Miyun CT workshop of the NUCTECH Company Limited and the arc maze of the radiation laboratory of the Academy of Military Medical Sciences were calculated using this method. The calculating results were compared with the MCNP simulating results and the measured results. For the commonly estimation of the maze dose rate, as long as the parameters chosen properly, this method can give a conservative result, and save time from simulation. It's hoped that this work could offer a reference for the maze design and the dose estimation method in the aftertime. (authors)

Selective impairment of subcategories of long-term memory in mice with hippocampal lesions accessed by the olfactory tubing maze.

Science.gov (United States)

Chaillan, F A; Marchetti, E; Soumireu-Mourat, B; Roman, F S

2005-03-30

A new apparatus, the olfactory tubing maze for mice, was developed recently to study learning and memory processes in mice in regard to their ethological abilities. As in humans, BALB/c mice with selective bilateral lesions of the hippocampal formation showed selective impairment of subcategories of long-term memory when tested with the olfactory tubing maze. After three learning sessions, control mice reached a high percentage of correct responses. They consistently made the olfactory-reward associations, but antero-dorsal and postero-ventral hippocampal-lesioned mice did not. However, all lesioned mice learned the paradigm and the timing of the task as fast and as well as control mice. These data suggest that the olfactory tubing maze can be used to study subcategories of memory, such as declarative and non-declarative memory, which are similar in some respects to those observed in humans. Consequently, possible memory effects of classical approaches (i.e., pharmacological or lesion studies) or genetic modifications in transgenic or gene-targeting mice can be effectively analyzed using this new apparatus.

Unraveling cognitive traits using the Morris water maze unbiased strategy classification (MUST-C) algorithm.

Science.gov (United States)

Illouz, Tomer; Madar, Ravit; Louzon, Yoram; Griffioen, Kathleen J; Okun, Eitan

2016-02-01

The assessment of spatial cognitive learning in rodents is a central approach in neuroscience, as it enables one to assess and quantify the effects of treatments and genetic manipulations from a broad perspective. Although the Morris water maze (MWM) is a well-validated paradigm for testing spatial learning abilities, manual categorization of performance in the MWM into behavioral strategies is subject to individual interpretation, and thus to biases. Here we offer a support vector machine (SVM) - based, automated, MWM unbiased strategy classification (MUST-C) algorithm, as well as a cognitive score scale. This model was examined and validated by analyzing data obtained from five MWM experiments with changing platform sizes, revealing a limitation in the spatial capacity of the hippocampus. We have further employed this algorithm to extract novel mechanistic insights on the impact of members of the Toll-like receptor pathway on cognitive spatial learning and memory. The MUST-C algorithm can greatly benefit MWM users as it provides a standardized method of strategy classification as well as a cognitive scoring scale, which cannot be derived from typical analysis of MWM data. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Liraglutide Improves Water Maze Learning and Memory Performance While Reduces Hyperphosphorylation of Tau and Neurofilaments in APP/PS1/Tau Triple Transgenic Mice.

Science.gov (United States)

Chen, Shuyi; Sun, Jie; Zhao, Gang; Guo, Ai; Chen, Yanlin; Fu, Rongxia; Deng, Yanqiu

2017-08-01

The purpose of this study was to explore how liraglutide affects AD-like pathology and cognitive function in APP/PS1/Tau triple transgenic (3 × Tg) Alzheimer disease (AD) model mice. Male 3 × Tg mice and C57BL/6 J mice were treated for 8 weeks with liraglutide (300 μg/kg/day, subcutaneous injection) or saline. Levels of phosphorylated tau, neurofilaments (NFs), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) in brain tissues were assessed with western blots. Fluoro-Jade-B labeling were applied to detect pathological changes. The Morris water maze (MWM) was used to assess the spatial learning and memory. Liraglutide decreased levels of hyperphosphorylated tau and NFs in 3 × Tg liraglutide-treated (Tg + LIR) mice, increased ERK phosphorylation, and decreased JNK phosphorylation. Liraglutide also decreased the number of degenerative neurons in the hippocampus and cortex of Tg + LIR mice, and shortened their escape latencies and increased their hidden platform crossings in the MWM task. Liraglutide did not significantly affect the animals' body weight (BW) or fasting blood glucose. Liraglutide can reduce hyperphosphorylation of tau and NFs and reduce neuronal degeneration, apparently through alterations in JNK and ERK signaling, which may be related to its positive effects on AD-like learning and memory impairment.

Repeated cognitive stimulation alleviates memory impairments in an Alzheimer's disease mouse model.

Science.gov (United States)

Martinez-Coria, Hilda; Yeung, Stephen T; Ager, Rahasson R; Rodriguez-Ortiz, Carlos J; Baglietto-Vargas, David; LaFerla, Frank M

2015-08-01

Alzheimer's disease is a neurodegenerative disease associated with progressive memory and cognitive decline. Previous studies have identified the benefits of cognitive enrichment on reducing disease pathology. Additionally, epidemiological and clinical data suggest that repeated exercise, and cognitive and social enrichment, can improve and/or delay the cognitive deficiencies associated with aging and neurodegenerative diseases. In the present study, 3xTg-AD mice were exposed to a rigorous training routine beginning at 3 months of age, which consisted of repeated training in the Morris water maze spatial recognition task every 3 months, ending at 18 months of age. At the conclusion of the final Morris water maze training session, animals subsequently underwent testing in another hippocampus-dependent spatial task, the Barnes maze task, and on the more cortical-dependent novel object recognition memory task. Our data show that periodic cognitive enrichment throughout aging, via multiple learning episodes in the Morris water maze task, can improve the memory performance of aged 3xTg-AD mice in a separate spatial recognition task, and in a preference memory task, when compared to naïve aged matched 3xTg-AD mice. Furthermore, we observed that the cognitive enrichment properties of Morris water maze exposer, was detectable in repeatedly trained animals as early as 6 months of age. These findings suggest early repeated cognitive enrichment can mitigate the diverse cognitive deficits observed in Alzheimer's disease. Published by Elsevier Inc.

Utility of the Hebb–Williams Maze Paradigm for Translational Research in Fragile X Syndrome: A Direct Comparison of Mice and Humans

Science.gov (United States)

Boutet, Isabelle; Collin, Charles A.; MacLeod, Lindsey S.; Messier, Claude; Holahan, Matthew R.; Berry-Kravis, Elizabeth; Gandhi, Reno M.; Kogan, Cary S.

2018-01-01

To generate meaningful information, translational research must employ paradigms that allow extrapolation from animal models to humans. However, few studies have evaluated translational paradigms on the basis of defined validation criteria. We outline three criteria for validating translational paradigms. We then evaluate the Hebb–Williams maze paradigm (Hebb and Williams, 1946; Rabinovitch and Rosvold, 1951) on the basis of these criteria using Fragile X syndrome (FXS) as model disease. We focused on this paradigm because it allows direct comparison of humans and animals on tasks that are behaviorally equivalent (criterion #1) and because it measures spatial information processing, a cognitive domain for which FXS individuals and mice show impairments as compared to controls (criterion #2). We directly compared the performance of affected humans and mice across different experimental conditions and measures of behavior to identify which conditions produce comparable patterns of results in both species. Species differences were negligible for Mazes 2, 4, and 5 irrespective of the presence of visual cues, suggesting that these mazes could be used to measure spatial learning in both species. With regards to performance on the first trial, which reflects visuo-spatial problem solving, Mazes 5 and 9 without visual cues produced the most consistent results. We conclude that the Hebb–Williams mazes paradigm has the potential to be utilized in translational research to measure comparable cognitive functions in FXS humans and animals (criterion #3). PMID:29643767

Delay-dependent working memory impairment in young-adult and aged 5-HT1BKO mice as assessed in a radial-arm water maze.

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Wolff, Mathieu; Benhassine, Narimane; Costet, Pierre; Hen, Rene; Segu, Louis; Buhot, Marie-Christine

2003-01-01

Serotonin (5-HT) plays a modulatory role in mnemonic functions, especially by interacting with the cholinergic system. The 5-HT1B receptor is a key target of this interaction. The 5-HT1B receptor knockout mice were found previously to exhibit a facilitation in hippocampal-dependent spatial reference memory learning. In the present study, we submitted mice to a delayed spatial working memory task, allowing the introduction of various delays between an exposure trial and a test trial. The 5-HT1BKO and wild-type mice learned the task in a radial-arm water maze (returning to the most recent presented arm containing the escape platform), and exhibited a high level of performance at delays of 0 and 5 min. However, at the delay of 60 min, only 5-HT1BKO mice exhibited an impairment. At a delay of 90 min, all mice were impaired. Treatment by scopolamine (0.8 mg/kg) induced the same pattern of performance in wild type as did the mutation for short (5 min, no impairment) and long (60 min, impairment) delays. The 22-month-old wild-type and knockout mice exhibited an impairment at short delays (5 and 15 min). The effect of the mutation affected both young-adult and aged mice at delays of 15, 30, and 60 min. Neurobiological data show that stimulation of the 5-HT1B receptor inhibits the release of acetylcholine in the hippocampus, but stimulates this in the frontal cortex. This dual function might, at least in part, explain the opposite effect of the mutation on reference memory (facilitation) and delay-dependent working memory (impairment). These results support the idea that cholinergic-serotonergic interactions play an important role in memory processes.

Prediction of rat behavior outcomes in memory tasks using functional connections among neurons.

Directory of Open Access Journals (Sweden)

Hu Lu

Full Text Available BACKGROUND: Analyzing the neuronal organizational structures and studying the changes in the behavior of the organism is key to understanding cognitive functions of the brain. Although some studies have indicated that spatiotemporal firing patterns of neuronal populations have a certain relationship with the behavioral responses, the issues of whether there are any relationships between the functional networks comprised of these cortical neurons and behavioral tasks and whether it is possible to take advantage of these networks to predict correct and incorrect outcomes of single trials of animals are still unresolved. METHODOLOGY/PRINCIPAL FINDINGS: This paper presents a new method of analyzing the structures of whole-recorded neuronal functional networks (WNFNs and local neuronal circuit groups (LNCGs. The activity of these neurons was recorded in several rats. The rats performed two different behavioral tasks, the Y-maze task and the U-maze task. Using the results of the assessment of the WNFNs and LNCGs, this paper describes a realization procedure for predicting the behavioral outcomes of single trials. The methodology consists of four main parts: construction of WNFNs from recorded neuronal spike trains, partitioning the WNFNs into the optimal LNCGs using social community analysis, unsupervised clustering of all trials from each dataset into two different clusters, and predicting the behavioral outcomes of single trials. The results show that WNFNs and LNCGs correlate with the behavior of the animal. The U-maze datasets show higher accuracy for unsupervised clustering results than those from the Y-maze task, and these datasets can be used to predict behavioral responses effectively. CONCLUSIONS/SIGNIFICANCE: The results of the present study suggest that a methodology proposed in this paper is suitable for analysis of the characteristics of neuronal functional networks and the prediction of rat behavior. These types of structures in cortical

Amazeobot : The construction of a maze mapping robot

OpenAIRE

REBECCA, WIKSTRÖM; MARTIN, SJÖGREN

2016-01-01

For the purpose of exploring how a computer can navigate through a maze, this project examines how a robot’s surroundings can be interpreted, mapped and navigated through, by applying common maze solving algorithms. The execution of the project involves infrared sensors used to interpret a controlled environment, consisting of a twodimensional board with paths. Movement and navigation decisions will be made possible by two DCmotorized wheels mounted on a platform, two simple computers and two...

Selective lesion of septal cholinergic neurons in rats impairs acquisition of a delayed matching to position T-maze task by delaying the shift from a response to a place strategy.

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Fitz, Nicholas F; Gibbs, Robert B; Johnson, David A

2008-12-16

This study tested the hypothesis that septal cholinergic lesions impair acquisition of a delayed matching to position (DMP) T-maze task in male rats by affecting learning strategy. Rats received either the selective cholinergic immunotoxin, 192 IgG-saporin (SAP) or artificial cerebrospinal fluid directly into the medial septum. Two weeks later, animals were trained to acquire the DMP task. SAP-treated rats took significantly longer to acquire the task than corresponding controls. Both SAP-treated and control rats adopted a persistent turn and utilized a response strategy during early periods of training. By the time rats reached criterion the persistent turn was no longer evident, and all rats had shifted to an allocentric strategy, i.e., were relying on extramaze cues to a significant degree. During the acquisition period, SAP-treated rats spent significantly more days showing a persistent turn and using a response strategy than corresponding controls. The added time spent using a response strategy accounted entirely for the added days required to reach criterion among the SAP-treated rats. This suggests that the principal mechanism by which septal cholinergic lesions impair DMP acquisition in male rats is by increasing the predisposition to use a response vs. a place strategy, thereby affecting the ability to switch from one strategy to another.

Behavioral consequences of predator stress in the rat elevated T-maze.

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Bulos, Erika Mondin; Pobbe, Roger Luis Henschel; Zangrossi, Helio

2015-07-01

Analyses of the behavioral reactions of rodents to predators have greatly contributed to the understanding of defense-related human psychopathologies such as anxiety and panic.We here investigated the behavioral consequences of exposing male Wistar rats to a live cat using the elevated T-maze test of anxiety. This test allows the measurement of two defensive responses: inhibitory avoidance and escape, which in terms of pathology have been associated with generalized anxiety and panic disorders, respectively. For comparative reasons, the effects of exposure to the cat were also assessed in the elevated plus-maze. The results showed that a 5-min exposure to the cat selectively facilitated inhibitory avoidance acquisition, an anxiogenic effect, without affecting escape expression in the elevated T-maze. This was seen immediately but not 30 min after contact with the predator. This short-lived anxiogenic effect was also detected in the elevated plus-maze. Previous administration of the benzodiazepine anxiolytic diazepam (2 mg/kg) decreased the immediate avoidance response to the predator and the neophobic reaction to a dummy cat used as a control stimulus. The drug also impaired inhibitory avoidance acquisition in the elevated T-maze, indicating an anxiolytic effect, without affecting escape performance. The results indicate that the state of anxiety evoked during contact with the predator generalizes to both elevated plus- and T-mazes, impacting on defensive responses associated with generalized anxiety disorder.

Glia protein aquaporin-4 regulates aversive motivation of spatial memory in Morris water maze.

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Zhang, Ji; Li, Ying; Chen, Zhong-Guo; Dang, Hui; Ding, Jian-Hua; Fan, Yi; Hu, Gang

2013-12-01

Although extensive investigation has revealed that an astrocyte-specific protein aquaporin-4 (AQP4) participates in regulating synaptic plasticity and memory, a functional relationship between AQP4 and learning processing has not been clearly established. This study was designed to test our hypothesis that AQP4 modulates the aversive motivation in Morris water maze (MWM). Using hidden platform training, we observed that AQP4 KO mice significantly decreased their swimming velocity compared with wild-type (WT) mice. To test for a relationship between velocities and escape motivation, we removed the platform and subjected a new group of mice similar to the session of hidden platform training. We found that KO mice exhibited a gradual reduction in swimming velocity, while WT mice did not alter their velocity. In the subsequent probe trial, KO mice after no platform training significantly decreased their mean velocity compared with those KO mice after hide platform training. However, all of KO mice were not impaired in their ability to locate a visible, cued escape platform. Our findings, along with a previous report that AQP4 regulates memory consolidation, implicate a novel role for this glial protein in modulating the aversive motivation in spatial learning paradigm. © 2013 John Wiley & Sons Ltd.

Differences between appetitive and aversive reinforcement on reorientation in a spatial working memory task.

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Golob, Edward J; Taube, Jeffrey S

2002-10-17

Tasks using appetitive reinforcers show that following disorientation rats use the shape of an arena to reorient, and cannot distinguish two geometrically similar corners to obtain a reward, despite the presence of a prominent visual cue that provides information to differentiate the two corners. Other studies show that disorientation impairs performance on certain appetitive, but not aversive, tasks. This study evaluated whether rats would make similar geometric errors in a working memory task that used aversive reinforcement. We hypothesized that in a task that used aversive reinforcement rats that were initially disoriented would not reorient by arena shape and thus make similar geometric errors. Tests were performed in a rectangular arena having one polarizing cue. In the appetitive condition water consumption was the reward. The aversive condition was a water maze task with reinforcement provided by escape to a hidden platform. In the aversive condition rats returned to the reinforced corner significantly more often than in the dry condition, and did not favor the diagonally opposite corner. Results show that rats can use cues besides arena shape to reorient in an aversive reinforcement condition. These findings may also reflect different strategies, with an escape/homing strategy in the wet condition and a foraging strategy in the dry condition.

Penentuan Nilai Motorik Halus Anak Dengan Game Magic Maze Menggunakan Metode Mamdani

OpenAIRE

Fadly, Muhammad

2015-01-01

Motor development is a very important factor in the development of the whole child. fine motor skills are very important because it affects the other terms of learning in early childhood. Therefore, it made the game Magic Maze to assess motor skills early childhood. Game Magic Maze in this study using Mamdani method in determining the values to a child's fine motor skills. Maze game will be made on the PC. 081402045

Maze Procedures for Atrial Fibrillation, From History to Practice.

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Kik, Charles; Bogers, Ad J J C

2011-10-01

Atrial fibrillation may result in significant symptoms, (systemic) thrombo-embolism, as well as tachycardia-induced cardiomyopathy with cardiac failure, and consequently be associated with significant morbidity and mortality. Nowadays symptomatic atrial fibrillation can be treated with catheter-based ablation, surgical ablation or hybrid approaches. In this setting a fairly large number of surgical approaches and procedures are described and being practised. It should be clear that the Cox-maze procedure resulted from building up evidence and experience in different steps, while some of the present surgical approaches and techniques are being based only on technical feasibility with limited experience, rather than on a process of consequent methodology. Some of the issues still under debate are whether or not the maze procedure can be limited to the left atrium or even to isolation of the pulmonary veins or that bi-atrial procedures are indicated, whether or not cardiopulmonary bypass is to be applied and which route of exposure facilitates an optimal result. In addition, maze procedures are not procedures guide by electrophysiological mapping. At least in theory not in all patients all lesions of the maze procedures are necessary. A history and aspects of current practise in surgical treatment of atrial fibrillation is presented.

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...

The application of a rodent-based Morris water maze (MWM) protocol to an investigation of age-related differences in human spatial learning.

Science.gov (United States)

Zhong, Jimmy Y; Magnusson, Kathy R; Swarts, Matthew E; Clendinen, Cherita A; Reynolds, Nadjalisse C; Moffat, Scott D

2017-12-01

The current study applied a rodent-based Morris water maze (MWM) protocol to an investigation of search performance differences between young and older adult humans. To investigate whether similar age-related decline in search performance could be seen in humans based on the rodent-based protocol, we implemented a virtual MWM (vMWM) that has characteristics similar to those of the MWM used in previous studies of spatial learning in mice. Through the use of a proximity to platform measure, robust differences were found between healthy young and older adults in search performance. After dividing older adults into good and poor performers based on a median split of their corrected cumulative proximity values, the age effects in place learning were found to be largely related to search performance differences between the young and poor-performing older adults. When compared with the young, poor-performing older adults exhibited significantly higher proximity values in 83% of 24 place trials and overall in the probe trials that assessed spatial learning in the absence of the hidden platform. In contrast, good-performing older adults exhibited patterns of search performance that were comparable with that of the younger adults in most place and probe trials. Taken together, our findings suggest that the low search accuracy in poor-performing older adults stemmed from potential differences in strategy selection, differences in assumptions or expectations of task demands, as well as possible underlying functional and/or structural changes in the brain regions involved in vMWM search performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Walkable self-overlapping virtual reality maze and map visualization demo

DEFF Research Database (Denmark)

Serubugo, Sule; Skantarova, Denisa; Evers, Nicolaj

2017-01-01

This paper describes our demonstration of a walkable self-overlapping maze and its corresponding map to facilitate asymmetric collaboration for room-scale virtual reality setups in public places.......This paper describes our demonstration of a walkable self-overlapping maze and its corresponding map to facilitate asymmetric collaboration for room-scale virtual reality setups in public places....

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.

A dissociation of dorso-lateral striatum and amygdala function on the same stimulus-response habit task.

Science.gov (United States)

McDonald, R J; Hong, N S

2004-01-01

This experiment tested the idea that the amygdala-based learning and memory system covertly acquires a stimulus-reward (stimulus-outcome) association during acquisition of a stimulus-response (S-R) habit task developed for the eight-arm radial maze. Groups of rats were given dorso-lateral striatal or amygdala lesions and then trained on the S-R habit task on the eight-arm radial maze. Rats with neurotoxic damage to the dorso-lateral striatum were severely impaired on the acquisition of the S-R habit task but showed a conditioned-cue preference for the stimulus reinforced during S-R habit training. Rats with neurotoxic damage to the amygdala were able to acquire the S-R habit task but did not show a conditioned-cue preference for the stimulus reinforced during S-R habit training. This pattern of results represents a dissociation of learning and memory functions of the dorsal striatum and amygdala on the same task.

[Automatic measurement of special leaning characteristics in mice during the water Morris maze test with inverted light].

Science.gov (United States)

Khotskin, N V; Fursenko, D V; Bazovkina, D V; Kulikov, V A; Kulikov, A V

2014-01-01

The description of the installation with inverted light is given as well as its software EthoStudio, which allows tracking the movements of any color animal in the water Morris maze (WMM) in high definition. The installation is based on the transmitted light technology (inverted light). The software gives possibility to estimate a wide range of learning indices. We have studied the statistic properties of three most widespread indices: latent time of platform finding, covered distance and the sum of distances to the center of the platform. The covered distance has shown the best statistic characteristics if compared to two other indices. The influence of polymorphism C1473G in the gene of the key serotonin synthesis enzyme, tryptophan hydroxylase 2, on the learning abilities of mice in WMM has been studied. Mice of the unique congenic lines B6-1473C and B6-12473G that differ by the polymorphic alleles C1473G have not demonstrated the association between the ability to learn and the genetically determined activity of tryptophan hydroxylase 2 in the brain.

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.

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

Science.gov (United States)

Bakker, Robbert C.; Akin, Sakir; Rizopoulos, Dimitris; Kik, Charles; Takkenberg, Johanna J.M.; Bogers, Ad J.J.C.

2013-01-01

OBJECTIVES 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. The objective of this study was to retrospectively evaluate the clinical safety and efficacy of the maze treatment performed at our institution. METHODS From March 2001 until February 2009, 169 patients underwent a modified maze procedure for atrial fibrillation at the Erasmus MC, Rotterdam. Patient characteristics, surgical procedure and follow-up data were obtained by reviewing the medical charts and consulting with the referring physicians. The efficacy of the procedure as measured by AF recurrence was analysed with a repeated measurements model. The quality of life of the patients was assessed with the SF-36 (a short-form health survey with 36 questions) questionnaire and compared with that of the general Dutch population. RESULTS Of the 169 patients who underwent a modified maze procedure, 163 had their maze procedure as a concomitant procedure. The 30-day mortality rate was 4.7% (n = 8). The rate of post-procedural AF recurrence varied significantly over time (P < 0.0001). Decreased left ventricular function, increased age and higher preoperative creatinine levels were predictors of AF recurrence. Quality of life, as measured with the SF-36 questionnaire, was comparable with that of the Dutch population for all health domains. CONCLUSIONS Concomitant maze is a relatively safe treatment that eliminates atrial fibrillation in the majority of patients, although the probability of recurrent AF increases with the passage of time. Decreased left ventricular function, increased age and higher preoperative creatinine levels are associated with an increased risk of AF recurrence. PMID:23103720

Effects of laterality and sex on cognitive strategy in a water maze place learning task and modification by nicotine and nitric oxide synthase inhibition in rats.

Science.gov (United States)

Kanit, L; Koylu, E O; Erdogan, O; Pogun, S

2005-08-15

The aim of the present study was to investigate sex differences in learning strategies and to elucidate the mechanisms, which may underlie these differences. In two separate experiments, rats were presented with different strategies that could be employed to learn the position of a platform in a water maze (WM); furthermore, rats received treatments that could influence these strategies. In the first experiment, we demonstrated that the response-learning paradigm can be applied to the WM and can be compared with visually cued learning and reversal learning. Naïve rats of either sex could acquire this protocol relatively easily. On the probe trial, where the rats are presented with a choice between using response versus visually cued learning, initially response learning was preferred, however, during these experiments, laterality emerged as a significant factor and rats trained to turn right had difficulty in reversing the learned pattern to find the platform. The second part of our study evaluated the effects of nicotine and nitric oxide synthase (NOS) inhibition on the aforementioned parameters. Drug treatments impaired acquisition compared to saline treatments and the effect was more pronounced with NOS inhibition. During the probe trial, while NOS inhibition enhanced the right-side bias in both sexes, nicotine treatment had the same effect only in males. In conclusion, naïve rats can acquire place learning using visible cues or response learning; however, there is a right side bias in both sexes and the laterality effect is more pronounced in male rats. In drug-treated animals, while NOS inhibition enhances laterality (right bias) in both sexes similarly, nicotine modifies the cognitive strategy in a sexually dimorphic manner by augmenting the right bias only in male rats.

MK-801 and memantine act differently on short-term memory tested with different time-intervals in the Morris water maze test.

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Duda, Weronika; Wesierska, Malgorzata; Ostaszewski, Pawel; Vales, Karel; Nekovarova, Tereza; Stuchlik, Ales

2016-09-15

N-methyl-d-aspartate receptors (NMDARs) play a crucial role in spatial memory formation. In neuropharmacological studies their functioning strongly depends on testing conditions and the dosage of NMDAR antagonists. The aim of this study was to assess the immediate effects of NMDAR block by (+)MK-801 or memantine on short-term allothetic memory. Memory was tested in a working memory version of the Morris water maze test. In our version of the test, rats underwent one day of training with 8 trials, and then three experimental days when rats were injected intraperitoneally with low- 5 (MeL), high - 20 (MeH) mg/kg memantine, 0.1mg/kg MK-801 or 1ml/kg saline (SAL) 30min before testing, for three consecutive days. On each experimental day there was just one acquisition and one test trial, with an inter-trial interval of 5 or 15min. During training the hidden platform was relocated after each trial and during the experiment after each day. The follow-up effect was assessed on day 9. Intact rats improved their spatial memory across the one training day. With a 5min interval MeH rats had longer latency then all rats during retrieval. With a 15min interval the MeH rats presented worse working memory measured as retrieval minus acquisition trial for path than SAL and MeL and for latency than MeL rats. MK-801 rats had longer latency than SAL during retrieval. Thus, the high dose of memantine, contrary to low dose of MK-801 disrupts short-term memory independent on the time interval between acquisition and retrieval. This shows that short-term memory tested in a working memory version of water maze is sensitive to several parameters: i.e., NMDA receptor antagonist type, dosage and the time interval between learning and testing. Copyright © 2016. Published by Elsevier B.V.

Medial Entorhinal Grid Cells and Head Direction Cells Rotate with a T-Maze More Often During Less Recently Experienced Rotations

Science.gov (United States)

Gupta, Kishan; Beer, Nathan J.; Keller, Lauren A.; Hasselmo, Michael E.

2014-01-01

Prior studies of head direction (HD) cells indicate strong landmark control over the preferred firing direction of these cells, with few studies exhibiting shifts away from local reference frames over time. We recorded spiking activity of grid and HD cells in the medial entorhinal cortex of rats, testing correlations of local environmental cues with the spatial tuning curves of these cells' firing fields as animals performed continuous spatial alternation on a T-maze that shared the boundaries of an open-field arena. The environment was rotated into configurations the animal had either seen or not seen in the past recording week. Tuning curves of both cell types demonstrated commensurate shifts of tuning with T-maze rotations during less recent rotations, more so than recent rotations. This strongly suggests that animals are shifting their reference frame away from the local environmental cues over time, learning to use a different reference frame more likely reliant on distal or idiothetic cues. In addition, grid fields demonstrated varying levels of “fragmentation” on the T-maze. The propensity for fragmentation does not depend on grid spacing and grid score, nor animal trajectory, indicating the cognitive treatment of environmental subcompartments is likely driven by task demands. PMID:23382518

Discussion on the optimization design on mazes of medical linear accelerator facilities

International Nuclear Information System (INIS)

Cao Lei; Zhang Wenyi; Liu Baiqun; Hou Changsong; Zhao Lancai

2007-01-01

Objective: To discuss the differences on the design and evaluation between the L-type and Z-type mazes of typical medical electric linear accelerator. Methods: The study is conducted by choosing some typical medical electric linear accelerators used in China, further analyzing on the running conditions of the accelerators in the mode of MV-X-ray, and referring to the late NCRP Report 51 and other references. Results: The radiation levels at the access to therapy room are effectively reduced by Z-type mazes. Conclusions: The Z-type mazes are advisable during the optimization design. (authors)

The role of rewarding and novel events in facilitating memory persistence in a separate spatial memory task

Science.gov (United States)

Salvetti, Beatrice; Morris, Richard G.M.; Wang, Szu-Han

2014-01-01

Many insignificant events in our daily life are forgotten quickly but can be remembered for longer when other memory-modulating events occur before or after them. This phenomenon has been investigated in animal models in a protocol in which weak memories persist longer if exploration in a novel context is introduced around the time of memory encoding. This study aims to understand whether other types of rewarding or novel tasks, such as rewarded learning in a T-maze and novel object recognition, can also be effective memory-modulating events. Rats were trained in a delayed matching-to-place task to encode and retrieve food locations in an event arena. Weak encoding with only one food pellet at the sample location induced memory encoding but forgetting over 24 h. When this same weak encoding was followed by a rewarded task in a T-maze, the memory persisted for 24 h. Moreover, the same persistence of memory over 24 h could be achieved by exploration in a novel box or by a rewarded T-maze task after a “non-rewarded” weak encoding. When the one-pellet weak encoding was followed by novel object exploration, the memory did not persist at 24 h. Together, the results confirm that place encoding is possible without explicit reward, and that rewarded learning in a separate task lacking novelty can be an effective memory-modulating event. The behavioral and neurobiological implications are discussed. PMID:24429424

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. Copyright © 2010 Elsevier B.V. All rights reserved.

Mathematical methods to model rodent behavior in the elevated plus-maze.

Science.gov (United States)

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

2013-11-15

The elevated plus maze is a widely used experimental test to study anxiety-like rodent behavior. It is made of four arms, two open and two closed, connected at a central area forming a plus shaped maze. The whole apparatus is elevated 50 cm from the floor. The anxiety of the animal is usually assessed by the number of entries and duration of stay in each arm type during a 5-min period. Different mathematical methods have been proposed to model the mechanisms that control the animal behavior in the maze, such as factor analysis, statistical inference on Markov chains and computational modeling. In this review we discuss these methods and propose possible extensions of them as a direction for future research. Copyright © 2013 Elsevier B.V. All rights reserved.

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.

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

Subtle alterations in memory systems and normal visual attention in the GAERS model of absence epilepsy.

Science.gov (United States)

Marques-Carneiro, J E; Faure, J-B; Barbelivien, A; Nehlig, A; Cassel, J-C

2016-03-01

Even if considered benign, absence epilepsy may alter memory and attention, sometimes subtly. Very little is known on behavior and cognitive functions in the Genetic Absence Epilepsy Rats from Strasbourg (GAERS) model of absence epilepsy. We focused on different memory systems and sustained visual attention, using Non Epileptic Controls (NECs) and Wistars as controls. A battery of cognitive/behavioral tests was used. The functionality of reference, working, and procedural memory was assessed in the Morris water maze (MWM), 8-arm radial maze, T-maze and/or double-H maze. Sustained visual attention was evaluated in the 5-choice serial reaction time task. In the MWM, GAERS showed delayed learning and less efficient working memory. In the 8-arm radial maze and T-maze tests, working memory performance was normal in GAERS, although most GAERS preferred an egocentric strategy (based on proprioceptive/kinesthetic information) to solve the task, but could efficiently shift to an allocentric strategy (based on spatial cues) after protocol alteration. Procedural memory and visual attention were mostly unimpaired. Absence epilepsy has been associated with some learning problems in children. In GAERS, the differences in water maze performance (slower learning of the reference memory task and weak impairment of working memory) and in radial arm maze strategies suggest that cognitive alterations may be subtle, task-specific, and that normal performance can be a matter of strategy adaptation. Altogether, these results strengthen the "face validity" of the GAERS model: in humans with absence epilepsy, cognitive alterations are not easily detectable, which is compatible with subtle deficits. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Maze learning by a hybrid brain-computer system.

Science.gov (United States)

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

2016-09-13

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.

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.

What does the CBM-maze test measure?

NARCIS (Netherlands)

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

Effect of methylphenidate on enhancement of spatial learning by novel alternated dual task.

Science.gov (United States)

Veetil, Praveen Kottath; Mukkadan, Joseph Kurian

2011-01-01

The novel alternated dual task (ADT) arranged rats to learn T-maze spontaneous alternation task and radial arm maze (RAM) task alternatively, and by doing ADT, rats could acquire the tasks more easily than non alternated dual task (NADT) group. Also retention capacity of ADT group was significantly more and ADT help to learn a complex task faster than learning it in isolation from other tasks. In the present study effect of methylphenidate (MPD), a mood elevator, known to enhance learning and memory, on ADT procedure is assessed. Also effect of ADT procedure and MPD on spatial learning and memory are compared. Different groups were assigned by administering MPD (intraperitoneal injection at a dose of 3 mg/kg body weight) during different phases of behavioural experiments, and control groups received saline injection. MPD administration increased both acquisition and retention capacities. The amelioration attained for retention of complex task by ADT procedure, could be achieved by NADT rats only by administration of MPD. The influence of ADT procedure on acquisition and retention of TM and RAM tasks were similar to the effects of MPD, especially for the RAM task. MPD at low dose is found to enhance the learning and memory capacity in rats, than deteriorating it, supporting the use of MPD as a drug to treat attention deficit hyperactive disorder. The recent reports suggesting the effect of MPD only on retention and not on acquisition could not be confirmed, as enhancement for both acquisition and retention was found in this study.

Cold Lake-Beaver River water management study update: Report of the Cold Lake Regional Water Management Task Force

International Nuclear Information System (INIS)

1994-01-01

The Cold Lake Regional Water Management Task Force was formed in 1992, comprising representatives from local governments, aboriginal groups, the oil industry, and the public. The Task Force's mandate was to advise Alberta Environmental Protection on updating the Cold Lake-Beaver River Water Management Plan, taking into acocunt the views and concerns of the public, industry, and local governments. Industrial water use was found to be the key issue to be addressed in the plan update, so the Task Force focused on reviewing industrial water supply options and developing recommendations on the appropriate water supply to meet long-term requirements. A subcommittee was established to monitor groundwater use by the heavy oil industry. This committee took readings at Imperial Oil's water production and observation wells on a biweekly basis. Nine options for supplying industrial water requirements were examined and evaluated using criteria including supply reliability, economic factors, and impacts on other users and the environment. The Task Force found that the preferred source of water for industrial use is the North Saskatchewan River, to be accessed by a water pipeline. The second and less desirable source of water for industrial use would be a system of weirs on Cold or Primrose Lakes and Wolf Lake, supplemented by the use of brackish water to the maximum extent possible. In the interim, industry was recommended to maximize its use of brackish water and continue to use surface and ground water within existing license limits. Other recommendations were to form provincial or regional boards to oversee water use and issue water licenses, to treat water as a resource, and to establish a fee for industrial use of water. 3 figs., 5 tabs

Sex difference in cue strategy in a modified version of the Morris water task: correlations between brain and behaviour.

Directory of Open Access Journals (Sweden)

Robin J Keeley

Full Text Available BACKGROUND: Sex differences in spatial memory function have been reported with mixed results in the literature, with some studies showing male advantages and others showing no differences. When considering estrus cycle in females, results are mixed at to whether high or low circulating estradiol results in an advantage in spatial navigation tasks. Research involving humans and rodents has demonstrated males preferentially employ Euclidean strategies and utilize geometric cues in order to spatially navigate, whereas females employ landmark strategies and cues in order to spatially navigate. METHODOLOGY/PRINCIPAL FINDINGS: This study used the water-based snowcone maze in order to assess male and female preference for landmark or geometric cues, with specific emphasis placed on the effects of estrus cycle phase for female rat. Performance and preference for the geometric cue was examined in relation to total hippocampal and hippocampal subregions (CA1&2, CA3 and dentate gyrus volumes and entorhinal cortex thickness in order to determine the relation between strategy and spatial performance and brain area size. The study revealed that males outperformed females overall during training trials, relied on the geometric cue when the platform was moved and showed significant correlations between entorhinal cortex thickness and spatial memory performance. No gross differences in behavioural performance was observed within females when accounting for cyclicity, and only total hippocampal volume was correlated with performance during the learning trials. CONCLUSIONS/SIGNIFICANCE: This study demonstrates the sex-specific use of cues and brain areas in a spatial learning task.

Performance of four different rat strains in the autoshaping, two-object discrimination, and swim maze tests of learning and memory.

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Andrews, J S; Jansen, J H; Linders, S; Princen, A; Broekkamp, C L

1995-04-01

The performance of four strains of rats commonly used in behavioural research was assessed in three different tests of learning and memory. The four strains included three outbred lines (Long-Evans, Sprague-Dawley, Wistar) and one inbred strain (S3). Learning and memory were tested using three different paradigms: autoshaping of a lever press, a two-object discrimination test, and performance in a two-island swim maze task. The pigmented strains showed better performance in the autoshaping procedure: the majority of the Long-Evans and the S3 rats acquired the response, and the majority of the Wistar and Sprague-Dawley failed to acquire the response in the set time. The albino strains were slightly better in the swim maze than the pigmented strains. There appeared to be a speed/accuracy trade-off in the strategy used to solve the task. This was also evident following treatment with the cholinergic-depleting agent hemicholinium-3. The performance of the Long-Evans rats was most affected by the treatment in terms of accuracy and the Wistar and Sprague-Dawleys in terms of speed. In the two-object discrimination test only the Long-Evans showed satisfactory performance and were able to discriminate a novel from a known object a short interval after initial exposure. These results show large task- and strain-dependent differences in performance in tests of learning and memory. Some of the performance variation may be due to emotional differences between the strains and may be alleviated by extra training. However, the response to pharmacological manipulation may require more careful evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

A novel technique to optimise the length of a linear accelerator treatment room maze without compromising radiation protection.

Science.gov (United States)

Al-Affan, I A M; Evans, S C; Qutub, M; Hugtenburg, R P

2018-03-01

Simulations with the FLUktuierende KAskade (FLUKA) Monte Carlo code were used to establish the possibility of introducing lead to cover the existing concrete walls of a linear accelerator treatment room maze, in order to reduce the dose of the scattered photons at the maze entrance. In the present work, a pilot study performed at Singleton Hospital in Swansea was used to pioneer the use of lead sheets of various thicknesses to absorb scattered low energy photons in the maze. The dose reduction was considered to be due to the strong effect of the photoelectric interaction in lead resulting in attenuation of the back-scattered photons. Calculations using FLUKA with mono-energetic photons were used to represent the main components of the x-ray spectrum up to 10 MV. Mono-energetic photons were used to enable the study of the behaviour of each energy component from the associated interaction processes. The results showed that adding lead of 1 to 4 mm thickness to the walls and floor of the maze reduced the dose at the maze entrance by up to 80%. Subsequent scatter dose measurements performed at the maze entrance of an existing treatment room with lead sheet of 1.3 mm thickness added to the maze walls and floor supported the results from the simulations. The dose reduction at the maze entrance with the lead in place was up to 50%. The variation between simulation and measurement was attributed to the fact that insufficient lead was available to completely cover the maze walls and floor. This novel proposal of partly, or entirely, covering the maze walls with lead a few millimetres in thickness has implications for the design of linear accelerator treatment rooms since it has the potential to provide savings, in terms of space and costs, when an existing maze requires upgrading in an environment where space is limited and the maze length cannot be extended sufficiently to reduce the dose.

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

Science.gov (United States)

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.

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. Copyright © 2010 Elsevier B.V. All rights reserved.

CBM maze-scores as indicators of reading level and growth for seventh-grade students

NARCIS (Netherlands)

Chung, S.; Espin, C.A.; Stevenson, C.E.

The technical adequacy of CBM maze-scores as indicators of reading level and growth for seventh-grade secondary-school students was examined. Participants were 452 Dutch students who completed weekly maze measures over a period of 23 weeks. Criterion measures were school level, dyslexia status,

Sex and estrous cycle-dependent changes in neurosteroid and benzodiazepine effects on food consumption and plus-maze learning behaviors in rats.

Science.gov (United States)

Reddy, D S; Kulkarni, S K

1999-01-01

Experiments were designed to investigate the influence of estrous cycle and gender of the rat on the effects of a gamma-aminobutyric acid type A (GABA(A)) receptor active neurosteroid, 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone), the benzodiazepine, triazolam, and a GABA(A) receptor antagonistic neurosteroid, delta5-androsten-3beta-ol-17-one sulfate (dehydroepiandrosterone sulfate), on food intake and elevated plus-maze learning behaviors. Allopregnanolone (0.25 mg/kg, s.c.) and triazolam (0.25 mg/kg, i.p.) produced a hyperphagic effect, while dehydroepiandrosterone sulfate (5 mg/kg, s.c.) elicited an anorectic effect. However, allopregnanolone was more potent in diestrous females, whereas triazolam exhibited significantly higher hyperphagic potency in estrus females. The extent of anorexia following dehydroepiandrosterone sulfate was alike in male and female rats. The triazolam- and allopregnanolone-induced hyperphagic effect was blocked by bicuculline (1 mg/kg, i.p.), a selective GABA(A) receptor antagonist. In contrast to triazolam, the hyperphagic effect of allopregnanolone was insensitive to flumazenil (5 mg/kg, i.p.), a benzodiazepine antagonist. Vehicle-treated diestrous rats displayed moderately higher latencies in the elevated plus-maze learning task than estrus or proestrus females. Although allopregnanolone and triazolam elicited equipotent learning deficits in plus-maze learning in male and female rats, the magnitude of impairment-induced by triazolam was significantly higher in diestrous females than proestrus females. Dehydroepiandrosterone sulfate enhanced memory performance only in male rats. Although the use of the elevated plus-maze as a learning paradigm with benzodiazepines and neurosteroids may be sensitive to changes in anxiety, the differential data suggest that neurosteroid-induced effects are at least partly specific to learning behavior. These results confirm the role of estrous cycle and sex of rats in modifying the potency of

Relationships among gender, cognitive style, academic major, and performance on the Piaget water-level task.

Science.gov (United States)

Hammer, R E; Hoffer, N; King, W L

1995-06-01

Many researchers have found that more college-age adults than would be expected fail Piaget's water-level task, with women failing more frequently than men. It has been hypothesized that differences in cognitive style may account for performance differences on the water-level task. In the present study, 27 male and 27 female architectural students and 27 male and 27 female liberal-arts students were assessed for their performance on both Piaget's Water-level Task and Witkin's Group Embedded Figures Test. No difference was found in performance of male and female architectural students on either task, but male liberal-arts students scored significantly higher than female liberal-arts students on both measures. A disembedding cognitive style predicted success on the water-level task for the architectural students but not for the liberal arts students.

Anticipatory activity in rat medial prefrontal cortex during a working memory task

Institute of Scientific and Technical Information of China (English)

Wenwen Bai; Tiaotiao Liu; Hu Yi; Shuangyan Li; Xin Tian

2012-01-01

Objective Working memory is a key cognitive function in which the prefrontal cortex plays a crucial role.This study aimed to show the firing patterns of a neuronal population in the prefrontal cortex of the rat in a working memory task and to explore how a neuronal ensemble encodes a working memory event.Methods Sprague-Dawley rats were trained in a Y-maze until they reached an 80％ correct rate in a working memory task.Then a 16-channel microelectrode array was implanted in the prefrontal cortex.After recovery,neuronal population activity was recorded during the task,using the Cerebus data-acquisition system.Spatio-temporal trains of action potentials were obtained from the original neuronal population signals.Results During the Y-maze working memory task,some neurons showed significantly increased firing rates and evident neuronal ensemble activity.Moreover,the anticipatory activity was associated with the delayed alternate choice of the upcoming movement.In correct trials,the averaged pre-event firing rate (10.86 ± 1.82 spikes/bin) was higher than the post-event rate (8.17 ± 1.15 spikes/bin) (P ＜0.05).However,in incorrect trials,the rates did not differ.Conclusion The results indicate that the anticipatory activity of a neuronal ensemble in the prefrontal cortex may play a role in encoding working memory events.

CBM Maze-Scores as Indicators of Reading Level and Growth for Seventh-Grade Students

Science.gov (United States)

Chung, Siuman; Espin, Christine A.; Stevenson, Claire E.

2018-01-01

The technical adequacy of CBM maze-scores as indicators of reading level and growth for seventh-grade secondary-school students was examined. Participants were 452 Dutch students who completed weekly maze measures over a period of 23 weeks. Criterion measures were school level, dyslexia status, scores and growth on a standardized reading test.…

Diazepam-stress interactions in the rat: effects on autoanalgesia and a plus-maze model of anxiety.

Science.gov (United States)

Taukulis, H K; Goggin, C E

1990-03-01

On six occasions spaced at least a week apart, two groups of rats were subjected to a variety of stressful conditions consisting of a restraint/bright light complex, either alone or in combination with a tail pinch, whole-body inversion, or partial immersion in cold water. One of these groups was injected with diazepam (2.0 mg/kg) 30 min prior to the stressors, while the other group experienced the drug in their home cages the following day. A third group also received the diazepam but was not exposed to the stressors. In three test sessions all animals were injected with either diazepam or saline and were then exposed to a novel stressor: a plus-maze used as a screening device for anxiolytic drugs. This was immediately followed by a tail-flick measure of analgesia. The longest tail-flick latencies, indicating stress-induced analgesia ("autoanalgesia"), were observed in the group that had not been exposed to stress prior to testing. The other two groups exhibited substantially shorter latencies but did not differ from one another, thus showing a "stress inoculation" effect that was uninfluenced by diazepam. In the plus-maze, diazepam tends to increase the amount of time rats will spend in the two exposed arms of the maze relative to the two enclosed arms. This effect was significantly attenuated in the group that had previously experienced the variety of stressors after a diazepam injection, suggesting a learned association between drug and stress that resulted in a diminution of the drug's anxiolytic property.

Water management. A core task of the Wismut remediation programme

International Nuclear Information System (INIS)

Paul, Michael; Meyer, Juergen; Jenk, Ulf; Kassahun, Andrea; Schramm, Andrea; Baacke, Delf; Forbrig, Norbert; Metschies, Thomas

2015-01-01

Water management and conventional technical water treatment are by far the most cost-intensive long-term tasks of the Wismut remediation programme. Over the medium term, there is no viable alternative to the operation of active systems to catch and treat contaminated mine waters at the Ronneburg, Schlema, Koenigstein, Poehla, Seelingstaedt and Heimsdorf sites. Based on the status quo this paper outlines the key issues of the Wismut GmbH water management strategy over the medium and long term. lt is focused primarily on achieving protection goals for potentially impacted water bodies in the surroundings of Wismut sites and on optimising associated remediation expenditure as well as on creating the prerequisites for achieving low post-remedial care and maintenance or walk-away system status over the long term. The topic of this paper is the presentation of priority tasks related to future water management at Wismut sites in Saxony and Thuringia. The reflections are based on experiences and lessons learned and take into account current statutory management requirements referring to ground and surface water bodies affected by Wismut. The paper is based on a presentation made at the International Mining Symposium WISSYM 2015 on 2nd September 2015 in Bad Schlema, Germany.

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.

Sex differences in vicarious trial-and-error behavior during radial arm maze learning.

Science.gov (United States)

Bimonte, H A; Denenberg, V H

2000-02-01

We investigated sex differences in VTE behavior in rats during radial arm maze learning. Females made more VTEs than males, although there were no sex differences in learning. Further, VTEs and errors were positively correlated during the latter testing sessions in females, but not in males. This sex difference may be a reflection of differences between the sexes in conflict behavior or cognitive strategy while solving the maze.

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

Development of locomotor activity of rat pups in figure-eight mazes.

Science.gov (United States)

Ruppert, P H; Dean, K F; Reiter, L W

1985-05-01

In a series of four experiments, social and experiential factors that influence the development of motor activity in rat pups were examined. Motor activity was monitored from postnatal Days 13 to 21 as photocell interruptions in figure-eight mazes and comparisons were made between pups maintained in a nest box containing a dam and siblings and allowed access to the maze for 23 hr/day, pups tested daily for 1 hr/day vs pups tested only on postnatal Days 15, 18, or 21, pups tested daily for either 5 min, 30 min, or 1 hr/day, and pups tested daily for 30 min/day either singly in a maze, paired with a littermate, or paired with an anesthetized pup of the same age. A monotonic increase in activity was seen for nest-box testing, minimal developmental change was seen for pups tested on only a single day or for pups tested with an anesthetized pup, whereas all other groups showed an inverted U-shaped profile of activity which was influenced by the duration of testing and/or the presence of a littermate. These data emphasize the relevance of environmental factors as determinants of preweaning behavior.

On the tenth value distance of the photon field along the maze of high-energy linear accelerator vaults.

Science.gov (United States)

Han, Zhaohui; Chin, Lee M

2018-03-01

There is a wide range in the reported photon tenth value distance (TVD) in the maze of high-energy linear accelerator vaults. In order to gain insight into the appropriate use of the TVD value during door design, we performed measurements of the photon dose in the maze of four vaults. In addition, our study represents the first to describe a scenario where an inner borated polyethylene (BPE) door for neutron shielding is installed in the maze downstream to Point A, the point on the maze centerline that is just visible from the isocenter. The measurements were made along the maze centerline at 1 m above the floor. In all cases, the accelerator operated at a nominal energy of 15 MV. Of the four vaults, three were equipped with an inner BPE door at a distance of 1.0-2.1 m downstream to Point A. The door was made of 10.16 cm (4″) BPE sandwiched between two 0.635 cm (1/4″) steel face plates. The photon dose in the maze without a BPE door decreases exponentially with a characteristic TVD of 6 m beyond a distance of 2.5 m from Point A. The presence of a BPE door in an identical vault not only reduces the photon intensity in the maze by about an order of magnitude, but also softens the energy spectrum with a shortened TVD of 4.7 m, significantly lessening the shielding burden at the outer maze entrance. In contrast to the common use of Point A as the reference point to specify distance, the photon dose in the maze with a BPE door located downstream to Point A can be satisfactorily described as exponential functions of the distance measured from the door, which shows good consistency among the three vaults of different room parameters. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Voluntary Exercise Improves Performance of a Discrimination Task through Effects on the Striatal Dopamine System

Science.gov (United States)

Eddy, Meghan C.; Stansfield, Katherine J.; Green, John T.

2014-01-01

We have previously demonstrated that voluntary exercise facilitates discrimination learning in a modified T-maze. There is evidence implicating the dorsolateral striatum (DLS) as the substrate for this task. The present experiments examined whether changes in DLS dopamine receptors might underlie the exercise-associated facilitation. Infusing a…

Effects of an electrolytic lesion of the prelimbic area on anxiety-related and cognitive tasks in the rat

NARCIS (Netherlands)

Gispen, W.H.; Maaswinkel, H.; Spruijt, B.M.

1996-01-01

The aim of this paper was to study the role of the prelimbic area of rats in response selection. A bilateral electrolytic lesion was made in the prelimbic area. The rats were tested in the Morris water-maze, the conditioned shock-prod burying test, the elevated plus-maze, a modified open field test,

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.

Maze solving algorithm and its programs using Z-80 assembler language for a robot

Energy Technology Data Exchange (ETDEWEB)

Takeno, J; Mukaidono, M

1982-01-01

In the first part the formation of a maze problem is introduced and the outline of this algorithm to solve a maze is explained in the second part. The third part describes the detail of this program, and the final part shows the program which has been developed using Z-80 assembler language. This program has portability for other robots using Z-80 microprocessors. 7 references.

Computational modelling and analysis of hippocampal-prefrontal information coding during a spatial decision-making task

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Thomas eJahans-Price

2014-03-01

Full Text Available We introduce a computational model describing rat behaviour and the interactions of neural populations processing spatial and mnemonic information during a maze-based, decision-making task. The model integrates sensory input and implements a working memory to inform decisions at a choice point, reproducing rat behavioural data and predicting the occurrence of turn- and memory-dependent activity in neuronal networks supporting task performance. We tested these model predictions using a new software toolbox (Maze Query Language, MQL to analyse activity of medial prefrontal cortical (mPFC and dorsal hippocampal (dCA1 neurons recorded from 6 adult rats during task performance. The firing rates of dCA1 neurons discriminated context (i.e. the direction of the previous turn, whilst a subset of mPFC neurons was selective for current turn direction or context, with some conjunctively encoding both. mPFC turn-selective neurons displayed a ramping of activity on approach to the decision turn and turn-selectivity in mPFC was significantly reduced during error trials. These analyses complement data from neurophysiological recordings in non-human primates indicating that firing rates of cortical neurons correlate with integration of sensory evidence used to inform decision-making.

Development rate rather than social environment influences cognitive performance in Australian black field crickets, Teleogryllus commodus.

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Anderson, Caitlin L; Kasumovic, Michael M

2017-01-01

Cognitive functioning is vital for enabling animals of all taxa to optimise their chances of survival and reproductive success. Learning and memory in particular are drivers of many evolutionary processes. In this study, we examine how developmental plasticity can affect cognitive ability by exploring the role the early social environment has on problem solving ability and learning of female black field crickets, Teleogryllus commodus. We used two learning paradigms, an analog of the Morris water maze and a novel linear maze, to examine cognitive differences between individuals reared in two acoustic treatments: silence or calling. Although there was no evidence of learning or memory, individuals that took longer to mature solved the Morris water maze more quickly. Our results suggest that increased investment into cognitive development is likely associated with increased development time during immature stages. Inconsistent individual performance and motivation during the novel linear maze task highlights the difficulties of designing ecologically relevant learning tasks within a lab setting. The role of experimental design in understanding cognitive ability and learning in more natural circumstances is discussed.

Development rate rather than social environment influences cognitive performance in Australian black field crickets, Teleogryllus commodus

Directory of Open Access Journals (Sweden)

Caitlin L. Anderson

2017-07-01

Full Text Available Cognitive functioning is vital for enabling animals of all taxa to optimise their chances of survival and reproductive success. Learning and memory in particular are drivers of many evolutionary processes. In this study, we examine how developmental plasticity can affect cognitive ability by exploring the role the early social environment has on problem solving ability and learning of female black field crickets, Teleogryllus commodus. We used two learning paradigms, an analog of the Morris water maze and a novel linear maze, to examine cognitive differences between individuals reared in two acoustic treatments: silence or calling. Although there was no evidence of learning or memory, individuals that took longer to mature solved the Morris water maze more quickly. Our results suggest that increased investment into cognitive development is likely associated with increased development time during immature stages. Inconsistent individual performance and motivation during the novel linear maze task highlights the difficulties of designing ecologically relevant learning tasks within a lab setting. The role of experimental design in understanding cognitive ability and learning in more natural circumstances is discussed.

Radiation protection of cyclotron vault with maze in PET Cyclotron Center

International Nuclear Information System (INIS)

Fueloep, Marko

2003-01-01

The PET Cyclotron center (PCC) is a complex for production, research and application of positron radiopharmaceuticals for PET (Positron Emission Tomography), which was commissioned this year (2004) in Bratislava, Slovak Republic. Positron radionuclides are produced by 18/9 MeV proton/deuteron cyclotron CYCLONE 18/9. Radiation protection of personnel and inhabitants against ionizing radiation in the PCC is solved with regard to the ICRP recommendations and Slovak regulatory system, protection rules and criteria and optimization of radiation protection. In the article comparisons of calculated and measured neutron and gamma dose equivalent rates around the CYCLONE 18/9 and at various points behind the shielding of cyclotron vault with maze are presented. Description of the CYCLONE 18/9 as a source of angular distribution of neutron energy spectra (production of 18 F was considered) was simulated by Monte Carlo code MCNPX. Code MCNP4B was used for shielding calculation of cyclotron vault with maze. Neutron energy spectra behind the shielding were measured by Bonner spectrometer. The values of neutron dose equivalent, which were calculated and measured around the CYCLONE 18/9 and at various points behind the shielding of cyclotron vault with maze, are within the range of factor 2. (authors)

Improved posttraumatic acquisition of a place learning task after repeated administration of a serotonergic agonist 8-OH-DPA

DEFF Research Database (Denmark)

Mala, Hana; Mogensen, Jesper

2008-01-01

specifically to 5-HT1A receptor subtypes. The effects were evaluated in terms of functional performance on an allocentric place learning task.    Participants/Materials/Methods: 68 animals served as experimental subjects. Initially, the rats were divided into 6 experimental groups, three of which were...... was given a single dose (5mg/kg/b.w.) of 8-OH-DPAT immediately after surgery (SINGLE TREATM), and one group was treated with daily administration of 8-OH-DPAT (5mg/kg/b.w.) for the six subsequent days (the first administration taking place immediately after surgery) (REPEATED TREATM). The acquisition...... of the water maze based place learning task started on the 8th day after surgery and continued daily for the next 25 days.   Results: The results show that within the lesioned groups, the group that was subjected to repeated administration of 8-OH-DPAT (REPEAT TREATM) showed a significantly improved...

Differentiation of Forebrain and Hippocampal Dopamine 1-Class Receptors, D1R and D5R, in Spatial Learning and Memory

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Sariñana, Joshua; Tonegawa, Susumu

2017-01-01

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. PMID:26174222

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

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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.

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,

Utility of finger maze test for learning and memory abilities in infants of cynomolgus monkeys exposed to thiamazole.

Science.gov (United States)

Inoue, Ayumi; Arima, Akihiro; Kato, Hirohito; Ebihara, Shizufumi

2014-11-01

A new type of learning and memory test using a finger maze was conducted in infant cynomolgus monkeys that were exposed to thiamazole (2 and 3.5 mg/kg per day to pregnant animals orally) during the fetal period (gestational days 120 to 150). We modified Tsuchida's original finger maze test method by reducing the number of trials per day and simplifying the criteria for achievement of training, and we added a long-term memory test. In the memory test, thiamazole-exposed infants required greater time to complete the finger maze test than the control infants although no effect was noted in the training or learning test. The results suggest that an impaired long-term memory could be detected by our modified finger maze test. © 2014 Japanese Teratology Society.

A behavioral paradigm to evaluate hippocampal performance in aged rodents for pharmacological and genetic target validation.

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Hilary Gerstein

Full Text Available Aged-related cognitive ability is highly variable, ranging from unimpaired to severe impairments. The Morris water maze (a reliable tool for assessing memory has been used to distinguish aged rodents that are superior learners from those that are learning impaired. This task, however, is not practical for pre- and post-pharmacological treatment, as the memory of the task is long lasting. In contrast, the object location memory task, also a spatial learning paradigm, results in a less robust memory that decays quickly. We demonstrate for the first time how these two paradigms can be used together to assess hippocampal cognitive impairments before and after pharmacological or genetic manipulations in rodents. Rats were first segregated into superior learning and learning impaired groups using the object location memory task, and their performance was correlated with future outcome on this task and on the Morris water maze. This method provides a tool to evaluate the effect of treatments on cognitive impairment associated with aging and neurodegenerative disorders.

The adenosine A2A antagonist MSX-3 reverses the effects of the dopamine antagonist haloperidol on effort-related decision making in a T-maze cost/benefit procedure.

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Mott, Allison M; Nunes, Eric J; Collins, Lyndsey E; Port, Russell G; Sink, Kelly S; Hockemeyer, Jörg; Müller, Christa E; Salamone, John D

2009-05-01

Mesolimbic dopamine (DA) is a critical component of the brain circuitry regulating behavioral activation and effort-related processes. Research involving choice tasks has shown that rats with impaired DA transmission reallocate their instrumental behavior away from food-reinforced tasks with high response requirements and instead select less effortful food-seeking behaviors. Previous work showed that adenosine A(2A) antagonism can reverse the effects of the DA antagonist haloperidol in an operant task that assesses effort-related choice. The present work used a T-maze choice procedure to assess the effects of adenosine A(2A) and A(1) antagonism. With this task, the two arms of the maze have different reinforcement densities (four vs. two food pellets), and a vertical 44 cm barrier is positioned in the arm with the higher density, presenting the animal with an effort-related challenge. Untreated rats strongly prefer the arm with the high density of food reward and climb the barrier in order to obtain the food. Haloperidol produced a dose-related (0.05-0.15 mg/kg i.p.) reduction in the number of trials in which the rats chose the high-barrier arm. Co-administration of the adenosine A(2A) receptor antagonist MSX-3 (0.75, 1.5, and 3.0 mg/kg i.p.), but not the A(1) antagonist 8-cyclopentyl-1,3-dipropylxanthine (0.75, 1.5, and 3.0 mg/kg i.p.), reversed the effects of haloperidol on effort-related choice and latency. Adenosine A(2A) and D2 receptors interact to regulate effort-related decision making, which may have implications for the treatment of psychiatric symptoms such as psychomotor slowing or anergia that can be observed in depression, parkinsonism, and other disorders.

Working and reference memory across the estrous cycle of rat: a long-term study in gonadally intact females.

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Pompili, Assunta; Tomaz, Carlos; Arnone, Benedetto; Tavares, Maria Clotilde; Gasbarri, Antonella

2010-11-12

The results of many studies conducted over the past two decades suggested a role of estrogen on mammal's ability to learn and remember. In the present paper, we analyzed the influence that the endogenous fluctuation of estrogen, naturally present across the different phases of estrous cycle of female rats, can exert over the performance of tasks utilized to assess memory. In particular, we analyzed the performances in an eight arms radial maze task, dependent upon working memory, and in a water maze (WM) task, dependent upon spatial reference memory. The water maze is aversively motivated by the desire to escape onto a safe platform, whereas the radial arm maze (RAM) is motivated by food reward. The difference in reinforcement may affect the speed of learning, the strategy adopted and the necessity for accurate navigation. Therefore, coherent results obtained through the two different tasks can be due to mnemonic factors. The study was conducted during a long period of time, 14 months, utilizing gonadally intact females, without pharmacological and surgical treatments. In order to evaluate the post-acquisition phase we first trained the animals to reach the criterion in performing tasks, and then we submitted them to experimental phase. Our results show that estrogen can have an effect on memory processes, and that this effect may be different in relation to different kinds of memory. In fact, in our study, estrogen selectively improved working memory, but not reference memory, during post-acquisition performance of a RAM task with four baited and four un-baited arms. Moreover, WM performances showed that estrogen have a negative effect on spatial reference memory. (c) 2010 Elsevier B.V. All rights reserved.

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

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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

2012-06-05

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. Copyright © 2012 Elsevier B.V. All rights reserved.

Age- and sex-related disturbance in a battery of sensorimotor and cognitive tasks in Kunming mice.

Science.gov (United States)

Chen, Gui-Hai; Wang, Yue-Ju; Zhang, Li-Qun; Zhou, Jiang-Ning

2004-12-15

A battery of tasks, i.e. beam walking, open field, tightrope, radial six-arm water maze (RAWM), novel-object recognition and olfactory discrimination, was used to determine whether there was age- and sex-related memory deterioration in Kunming (KM) mice, and whether these tasks are independent or correlated with each other. Two age groups of KM mice were used: a younger group (7-8 months old, 12 males and 11 females) and an older group (17-18 months old, 12 males and 12 females). The results showed that the spatial learning ability and memory in the RAWM were lower in older female KM mice relative to younger female mice and older male mice. Consistent with this, in the novel-object recognition task, a non-spatial cognitive task, older female mice but not older male mice had impairment of short-term memory. In olfactory discrimination, another non-spatial task, the older mice retained this ability. Interestingly, female mice performed better than males, especially in the younger group. The older females exhibited sensorimotor impairment in the tightrope task and low locomotor activity in the open-field task. Moreover, older mice spent a longer time in the peripheral squares of the open-field than younger ones. The non-spatial cognitive performance in the novel-object recognition and olfactory discrimination tasks was related to performance in the open-field, whereas the spatial cognitive performance in the RAWM was not related to performance in any of the three sensorimotor tasks. These results suggest that disturbance of spatial learning and memory, as well as selective impairment of non-spatial learning and memory, existed in older female KM mice.

Effect of single and fractionated x-irradiation on maze learning ability of mice

International Nuclear Information System (INIS)

Aoyama, Takashi; Norimura, Toshiyuki; Nakamura, Takeshi; Yoshikawa, Isao

1976-01-01

Fifty-six-day-old male ddk mice at the starting of the investigation were used as subjects through the experiment for 64 weeks. After 15 days' preliminary training, and 16 times of weekly trial training using complete maze, 15 mice received a single 224 rads of x-rays (S group), another 15 mice received two 112 rads spaced two weeks apart (F group) and another 15 mice were sham-irradiated (Control group). Then those mice were tested on the multiple T-maze with nine-choice points and change of performance was observed in terms of errorchoices by giving one test trial a week. We introduced the concept of ''confusional trials'' as an index for surmising to what extent mice failed to exhibit good maze learning habits. In the results, the F group showed significantly worse performance than the two other groups at early stages, opposite to it the S group exhibited the same, but at late stages after irradiation. The worse performance of F group should be considered to be due to the psychological after-effect to fractionated irradiation and that for S group could be assumed to be due to the acceleration of aging by the irradiation. (auth.)

Model testing of a 10-kg high explosive blast attenuation maze

International Nuclear Information System (INIS)

Bacigalupi, C.M.; Burton, W.A.

1981-01-01

The basement area of the proposed High Explosive Applications Facility (HEAF) at the Lawrence Livermore National Laboratory includes 10-kg HE assembly and process cells, and a 10-kg corridor for the transport of up to 10 kg of HE from the receiving dock to the cells and to the experimental firing tanks. Previous model experiments developed a process cell-maze configuration that attenuated the effects of an accidental 10-kg detonation to acceptable levels (maximum of 10 to 11 psi reflected). This document reports 1/8-scale model tests conducted to confirm the maze design and to determine the blast pressures in adjacent areas in the final HEAF building configuration. In addition, pressure/time information was obtained at selected points in the model expansion chamber to provide the architect-engineer with information for structural design

Brain functional network changes following Prelimbic area inactivation in a spatial memory extinction task.

Science.gov (United States)

Méndez-Couz, Marta; Conejo, Nélida M; Vallejo, Guillermo; Arias, Jorge L

2015-01-01

Several studies suggest a prefrontal cortex involvement during the acquisition and consolidation of spatial memory, suggesting an active modulating role at late stages of acquisition processes. Recently, we have reported that the prelimbic and infralimbic areas of the prefrontal cortex, among other structures, are also specifically involved in the late phases of spatial memory extinction. This study aimed to evaluate whether the inactivation of the prelimbic area of the prefrontal cortex impaired spatial memory extinction. For this purpose, male Wistar rats were implanted bilaterally with cannulae into the prelimbic region of the prefrontal cortex. Animals were trained during 5 consecutive days in a hidden platform task and tested for reference spatial memory immediately after the last training session. One day after completing the training task, bilateral infusion of the GABAA receptor agonist Muscimol was performed before the extinction protocol was carried out. Additionally, cytochrome c oxidase histochemistry was applied to map the metabolic brain activity related to the spatial memory extinction under prelimbic cortex inactivation. Results show that animals acquired the reference memory task in the water maze, and the extinction task was successfully completed without significant impairment. However, analysis of the functional brain networks involved by cytochrome oxidase activity interregional correlations showed changes in brain networks between the group treated with Muscimol as compared to the saline-treated group, supporting the involvement of the mammillary bodies at a the late stage in the memory extinction process. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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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.

Sex differences in a landmark environmental re-orientation task only during the learning phase.

Science.gov (United States)

Piccardi, Laura; Bianchini, Filippo; Iasevoli, Luigi; Giannone, Gianluca; Guariglia, Cecilia

2011-10-10

Sex differences are consistently reported in human navigation. Indeed, to orient themselves during navigation women are more likely to use landmark-based strategies and men Euclidean-based strategies. The difference could be due to selective social pressure, which fosters greater spatial ability in men, or biological factors. And the great variability of the results reported in the literature could be due to the experimental setting more than real differences in ability. In this study, navigational behaviour was assessed by means of a place-learning task in which a modified version of the Morris water maze for humans was used to evaluate sex differences. In using landmarks, sex differences emerged only during the learning phase. Although the men were faster than the women in locating the target position, the differences between the sexes disappeared in delayed recall. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Use of maze in cyclotron hoppers

International Nuclear Information System (INIS)

Fernandes, Fernando A.; Alves, Juliano S.; Fochesatto, Cintia; Cerioli, Luciane; Borges, Joao Alfredo; Gonzalez, Delfin; Silva, Daniel C.

2013-01-01

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 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

Real-time changes in hippocampal energy demands during a spatial working memory task.

Science.gov (United States)

Kealy, John; Bennett, Rachel; Woods, Barbara; Lowry, John P

2017-05-30

Activity-dependent changes in hippocampal energy consumption have largely been determined using microdialysis. However, real-time recordings of brain energy consumption can be more accurately achieved using amperometric sensors, allowing for sensitive real-time monitoring of concentration changes. Here, we test the theory that systemic pre-treatment with glucose in rats prevents activity-dependent decreases in hippocampal glucose levels and thus enhances their performance in a spontaneous alternation task. Male Sprague Dawley rats were implanted into the hippocampus with either: 1) microdialysis probe; or 2) an oxygen sensor and glucose biosensor co-implanted together. Animals were pre-treated with either saline or glucose (250mg/kg) 30min prior to performing a single 20-min spontaneous alternation task in a +-maze. There were no significant differences found between either treatment group in terms of spontaneous alternation performance. Additionally, there was a significant difference found between treatment groups on hippocampal glucose levels measured using microdialysis (a decrease associated with glucose pre-treatment in control animals) but not amperometry. There were significant increases in hippocampal oxygen during +-maze exploration. Combining the findings from both methods, it appears that hippocampal activity in the spontaneous alternation task does not cause an increase in glucose consumption, despite an increase in regional cerebral blood flow (using oxygen supply as an index of blood flow) and, as such, pre-treatment with glucose does not enhance spontaneous alternation performance. Copyright © 2017 Elsevier B.V. All rights reserved.

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...

[Cox/maze III procedure combined with mitral valve replacement in treatment of rheumatic mitral valve disease with atrial fibrilation].

Science.gov (United States)

Chen, Rukun; Wang, Yongqing; Chen, Yongbing; Chen, Suocheng

2002-06-25

To compare the curative effect of Cox/maze III procedure combined with mitral replacement and that of mitral valve replacement (MVR). Fifty-six patients suffering from rheumatic heart disease with atrial fibrillation (AF) were treated by Cox/maze III procedure combined with MVR (maze group). Another 56 age, sex, and heart function-matched patients with the same diagnosis underwent MVR alone during the same period. Warfarin was administered after operation in both groups. Comparison of operative complication and curative effects was made. The aortic cross-clamp time and cardio pulmonary bypass time (CPB) were longer in maze group than in MVT group (75 +/- 22 min vs 41 +/- 11 min, P Atrial contractility was restored in all patients with sinus rhythm. One year after operation, 98.18% patients' cardiac function changed to grade and 1.82% changed to grade II. In MVR group AF disappeared after operation temporarily for 24 hours in 7 patients and re-appeared, and AF disappeared in one patients for 2 years so far. One year after operation, the cardiac function of 94.6% patients in MVR group changed to grade I, of 3.6% patients to grade II, and of 1.8% patients to grade III. No serious hemorrhage relate d to anticoagulant therapy happened. One patient in MVR group suffered from hemiplegia due to cerebral embolism. The late mortality was 1.8% on maze group amd 3.6% in MVR group. Cox/maze III procedure combined with NVR is safe and effective in treating rheumatic heart disease with AF.

Research and development of a heat-pump water heater. Volume 2. R and D task reports

Energy Technology Data Exchange (ETDEWEB)

Dunning, R.L.; Amthor, F.R.; Doyle, E.J.

1978-08-01

The heat pump water heater is a device that works much like a window air conditioner except that heat from the home is pumped into a water tank rather than to the outdoors. The objective established for the device is to operate with a Coefficient of Performance (COP) of 3 or, an input of one unit of electric energy would create three units of heat energy in the form of hot water. With such a COP, the device would use only one-third the energy and at one-third the cost of a standard resistance water heater. This Volume 2 contains the final reports of the three major tasks performed in Phase I. In Task 2, a market study identifies the future market and selects an initial target market and channel of distribution, all based on an analysis of the parameters affecting feasibility of the device and the factors that will affect its market acceptance. In the Task 3 report, the results of a design and test program to arrive at final designs of heat pumps for both new water heaters and for retrofitting existing water heaters are presented. In the Task 4 report, a plan for an extensive field demonstration involving use in actual homes is presented. Volume 1 contains a final summary report of the information in Volume 2.

Impact of a modified Maze procedure on the atrial hormonal function and level of myocardial damage markers

Directory of Open Access Journals (Sweden)

S. I. Zheleznev

2015-10-01

Full Text Available Surgical treatment of atrial fibrillation (AF in patients with valvular heart disease remains one of the most pressing problems in cardiac surgery. The purpose of the study was to determine the dynamics of proANP and myocardial damage markers depending on a modification of the radiofrequency (RF Maze procedure used. The study involved 86 patients operated over a period from November 2007 to December 2010. A concomitant RF Maze procedure during mitral valve (MV surgery was performed in two groups of the cohort; in group 1 it was the standard Maze IV scheme, in group 2 it was the modified one. In both groups we assessed the levels of proANP and myocardial damage markers. In group 1 a more significant decrease in proANP (by 4 times was seen as compared to group 2 (by half. In group 1, the pleural effusion rate was 46.2%, and thoracocentesis rate reached 25.6%. In group 2, the corresponding rates were lower,14.9% and 27.7%. During the first postoperative day there was an increase in creatine phosphokinase MB fraction and Troponin T in both groups, and the rise was significantly higher in group 1. It should be noted that modified Maze IV RF ablation results in 80% freedom from AF, which is consistent with that of the standard Maze IV scheme. In patients with left atrial ablation the proANP secretion is less prominent early after surgery, and myocardial damage is lower in comparison with biatrial ablation.

Sex differences in chronic stress effects on cognition in rodents.

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Luine, Victoria; Gomez, Juan; Beck, Kevin; Bowman, Rachel

2017-01-01

Chronic stress causes deleterious changes in physiological function in systems ranging from neural cells in culture to laboratory rodents, sub-human primates and humans. It is notable, however, that the vast majority of research in this area has been conducted in males. In this review, we provide information about chronic stress effects on cognition in female rodents and contrast it with responses in male rodents. In general, females show cognitive resilience to chronic stressors which impair male cognitive function using spatial tasks including the radial arm maze, radial arm water maze, Morris water maze, Y-maze and object placement. Moreover, stress often enhances female performance in some of these cognitive tasks. Memory in females is not affected by stress in non-spatial memory tasks like recognition memory and temporal order recognition memory while males show impaired memory following stress. We discuss possible bases for these sex-dependent differences including the use of different strategies by the sexes to solve cognitive tasks. Whether the sex differences result from changes in non-mnemonic factors is also considered. Sex-dependent differences in alcohol and drug influences on stress responses are also described. Finally, the role of neurally derived estradiol in driving sex differences and providing resilience to stress in females is shown. The importance of determining the nature and extent of sex differences in stress responses is that such differences may provide vital information for understanding why some stress related diseases have different incidence rates between the sexes and for developing novel therapeutic treatments. Copyright © 2016 Elsevier Inc. All rights reserved.

Lipopolysaccharide causes deficits in spatial learning in the watermaze but not in BDNF expression in the rat dentate gyrus.

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Shaw, K N; Commins, S; O'Mara, S M

2001-09-28

We investigated the effects of a single injection and a daily injection of lipopolysaccharide (LPS) on spatial learning and brain-derived neurotrophic factor (BDNF) expression in the rat dentate gyrus. LPS is derived from the cell wall of Gram-negative bacteria and is a potent endotoxin that causes the release of cytokines such as interleukin-1 and tumour necrosis factor. LPS is thought to activate both the neuroimmune and neuroendocrine systems; it also blocks long-term potentiation in the hippocampus. Here, we examined the effects of LPS on a form of hippocampal-dependent learning-spatial learning in the water maze. Rats were injected with LPS intraperitoneally (100 microg/kg) and trained in the water maze. The first group of rats were injected on day 1 of training, 4 h prior to learning the water maze task. Groups 2 and 3 were injected daily, again 4 h prior to the water-maze task; group 2 with LPS and group 3 with saline. A number of behavioural variables were recorded by a computerised tracking system for each trial. The behavioural results showed a single injection of LPS (group 1) impaired escape latency in both the acquisition and retention phases of the study, whereas a daily injection of LPS did not significantly impair acquisition or retention. BDNF expression was analysed in the dentate gyrus of all animals. No significant differences in BDNF expression were found between the three groups.

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

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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

MK-801 induced amnesia for the elevated plus-maze in mice

Czech Academy of Sciences Publication Activity Database

Hliňák, Zdeněk; Krejčí, I.

2002-01-01

Roč. 131, 1-2 (2002), s. 221-225 ISSN 0166-4328 R&D Projects: GA ČR GA309/00/1644 Institutional research plan: CEZ:AV0Z5011922 Keywords : amnesia * elevated plus-maze * MK-801 Subject RIV: FH - Neurology Impact factor: 2.791, year: 2002

Influence of spatial and temporal manipulations on the anxiolytic efficacy of chlordiazepoxide in mice previously exposed to the elevated plus-maze.

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Holmes, A; Rodgers, R J

1999-11-01

It has been widely reported that the anxiolytic efficacy of benzodiazepines in the elevated plus-maze test is abolished in subjects (rats or mice) that have been given a single prior undrugged experience of the test apparatus. The present series of experiments was designed to further characterise the key experiential determinants of this intriguing phenomenon in Swiss Webster mice. Using a standard 5 min test duration for both trials, Experiment 1 confirmed the anxiolytic efficacy of chlordiazepoxide (CDP; 5-20 mg/kg) in mice naive to the plus-maze, but a virtual elimination of drug effects in animals that had been pre-exposed to the maze 24 h earlier. Experiments 2 and 3 demonstrated that, while extending the duration of initial exposure to 10 min did not prevent the loss of CDP (10 mg/kg) efficacy in a standard-duration second trial, increasing the duration of both trials reinstated an anxiolytic profile for the compound. Finally, although trial 1 confinement to an open arm did not compromise CDP efficacy when animals were subsequently allowed to freely explore the maze (Experiment 4), closed arm confinement during initial exposure abolished the drug's anxiolytic action upon retest (Experiment 5). In contrast to previous findings in rats, these data suggest that the experientially induced loss of benzodiazepine efficacy in the mouse plus-maze depends rather critically upon prior discovery and exploration of relatively safe areas of the maze (i.e. closed arms). Results are discussed in relation to the hypothesis that the absence of an anxiolytic response to benzodiazepines in plus-maze-experienced subjects reflects the acquisition of an open arm phobia during trial 1.

Molecular Signatures and Diagnostic Biomarkers of Cumulative Blast-Graded Mild TBI

Science.gov (United States)

2014-12-01

experiment: to assign rat ID #404-430 (the last rat examined was 403). Provided rats arrive Monday or Tuesday , Jun 10-11. 30 days post-blast endpoint...and 36.6 kPa 6, 24 h and 1 week Single or 12 blasts (24 h at 36.6 kPa) Three body orientation (sideway, facing away vs. frontal) Morris water maze task...0.5, 3, 6, and 10 h and 1, 2, 3, 5, and 7 days Single Morris water maze: impaired cognitive function: 48 h post injury Dose-dependent rise in

Anti-anxiety activity of successive extracts of Angelica archangelica Linn. on the elevated T-maze and forced swimming tests in rats.

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Kumar, Dinesh; Bhat, Zulfiqar Ali; Shah, M Y

2012-09-01

Angelica archangelica Linn. is widely used in food and liquor preparations and also in Kashmiri folk medicine to reduce anxiety. We evaluated the anxiolytic effect of successive extracts of A. archangelica linn. (SAE) on rats tested in the elevated T-maze test (an animal model of generalized anxiety) at doses that exhibit antidepressant-like activity in humans. A. archangelica (1 kg) was subjected to successive extraction in a soxhlet apparatus with solvents [petroleum ether (40-60 degrees C), chloroform, ethyl acetate, methanol and decoction with water] in order of increasing polarity (yield: 6.9%, 7.3%, 5.1%, 11.88% and 8.2% w/w, respectively). SAE were evaluated for anxiolytic effects using the elevated T-maze and forced swimming tests in rats. Oral dosing of diazepam (1 mg/kg) and extracts (50, 100 and 200 mg/kg) clearly showed an anxiolytic-like profile in the elevated T-maze test: it increased one-way escape and decreased inhibitory avoidance on the first, third and seventh day. In the forced swimming test, imipramine and SAE showed antidepressant- and anxiolytic-like effects as reflected by increased climbing time, swimming time and decreased immobility time on the first, third and seventh day. Aqueous and methanol extracts showed the most, petroleum ether (40-60 degrees C) and chloroform intermediate, and ethyl acetate the least anxiolytic activity (*P<0.05, **P<0.01, ***P< 0.001) in both models. These results suggest the anti-anxiety activity of various extracts of A. archangelica and strongly justify its use in traditional Indian medicine for the treatment of anxiety.

Lesions of reuniens and rhomboid thalamic nuclei impair radial maze win-shift performance.

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Hembrook, Jacqueline R; Mair, Robert G

2011-08-01

The reuniens (Re) and rhomboid (Rh) nuclei are major sources of thalamic input to hippocampus and medial prefrontal cortex. We compared effects of lesions in ReRh and other parts of the midline-intralaminar complex on tasks affected by lesions in terminal fields innervated by these nuclei, including: visuospatial reaction time (VSRT), a measure of sensory guided responding; serial VSRT, a measure of action sequence learning; and win/shift radial arm maze (RAM) measures of spatial memory. ReRh lesions affected RAM, but not VSRT or serial VSRT performance. The effects of caudal intralaminar lesions were doubly dissociated from ReRh lesions, affecting VSRT, but not RAM or serial VSRT performance. Rostral intralaminar lesions did not produce significant impairments, other than a subgroup with larger lesions that were impaired performing a delayed RAM task. Combined lesions damaging all three sites produced RAM deficits comparable to ReRh lesions and VSRT deficits comparable to caudal intralaminar lesions. Thus there was no indication that deficits produced by lesions in one site were exacerbated significantly by the cumulative effect of damage in other parts of the midline-intralaminar complex. The effects of ReRh lesions provide evidence that these nuclei affect memory functions of hippocampus and medial prefrontal cortex. The double dissociation observed between the effects of ReRh and caudal intralaminar nuclei provides evidence that different nuclei within the midline-intralaminar complex affect distinct aspects of cognition consistent with the effects of lesions in the terminal fields they innervate. Copyright © 2010 Wiley-Liss, Inc.

Influence of age on cognition and scopolamine induced memory impairment in rats measured in the radial maze paradigm.

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Appenroth, Dorothea; Fleck, Christian

2010-01-01

The influence of age on (1) cognition and (2) scopolamine (CAS 51-34-3) induced memory impairment in female rats was measured in the radial maze paradigm (RAM). (1) First training trials were done with 3 and 12 months old rats. Rats were trained to find all eight food baits in the RAM without errors and within 1 min. Both 3- and 12-month old rats need about 15 trials for the first-time learning of the RAM task. After intervals of 3 6 months, respectively, initially young rats were re-trained with an age of 6 and 12 months. Surprisingly, re-trained rats successfully completed the maze runs already after one re-training trial. Thus the phenomenon of preserved spatial memory was approved for female rats. (2) Memory impairment by scopolamine in the RAM was tested for the time in rats with an age of 3 months. first rats with thesame After a control run,the rats received an i.p. injection of either scopolamine hydrochloride (0.05 mg/100 g b. wt.) or saline vehicle. The effect of scopolamine on working memory was measured 20 min after administration. Training procedure and scopolamine administration were repeated at an age of 6, 12, 18, and 24 months in the same manner. The cognition impairment after scopolamine (number of errors: control: <1; scopolamine: 5-6) remains constant between 3 and 24 months of age. The only significant difference was the increase in run time in rats older than 18 months caused by degenerative changes developing with age.

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

Science.gov (United States)

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

2016-04-01

Subiculum is an important structure of the hippocampal formation and plays an imperative role in spatial learning and memory functions. We have demonstrated earlier the cognitive impairment following bilateral ventral subicular lesion (VSL) in rats. We found that short term exposure to enriched environment (EE) did not help to reverse the spatial memory deficits in water maze task suggesting the need for an appropriate enriched paradigm towards the recovery of spatial memory. In the present study, the efficacy of long term exposure of VSL rats to combination paradigm of environmental enrichment (EE), physical exercise and 18 C.W. diet (Combination Therapy - CT) in reversing the spatial memory deficits in Morris water maze task has been studied. Ibotenate lesioning of ventral subiculum produced significant impairment of performance in the Morris water maze and reduced the hippocampal neurogenesis in rats. Post lesion exposure to C.T. restored the hippocampal neurogenesis and improved the spatial memory functions in VSL rats. Our study supports the hypothesis that the combination paradigm is critical towards the development of an enhanced behavioral and cognitive experience especially in conditions of CNS insults and the associated cognitive dysfunctions. Copyright © 2016 Elsevier Inc. All rights reserved.

The relationship between anxiety and depression in animal models: a study using the forced swimming test and elevated plus-maze

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R. Andreatini

1999-09-01

Full Text Available The present study evaluated the correlation between the behavior of mice in the forced swimming test (FST and in the elevated plus-maze (PM. The effect of the order of the experiments, i.e., the influence of the first test (FST or PM on mouse behavior in the second test (PM or FST, respectively was compared to handled animals (HAND. The execution of FST one week before the plus-maze (FST-PM, N = 10, in comparison to mice that were only handled (HAND-PM, N = 10 in week 1, decreased % open entries (HAND-PM: 33.6 ± 2.9; FST-PM: 20.0 ± 3.9; mean ± SEM; P0.10. A prior test in the plus-maze (PM-FST did not change % immobility time in the FST when compared to the HAND-FST group (HAND-FST: 57.7 ± 3.9; PM-FST: 65.7 ± 3.2; mean ± SEM; P>0.10. Since these data suggest that there is an order effect, the correlation was evaluated separately with each test sequence: FST-PM (N = 20 and PM-FST (N = 18. There was no significant correlation between % immobility time in the FST and plus-maze indexes (% time and entries in open arms in any test sequence (r: -0.07 to 0.18. These data suggest that mouse behavior in the elevated plus-maze is not related to behavior in the forced swimming test and that a forced swimming test before the plus-maze has an anxiogenic effect even after a one-week interval.

Photon dose evaluation at the entrance of radiotherapy bunkers without maze

International Nuclear Information System (INIS)

Facure, Alessandro; Salata, Camila

2017-01-01

Radiation protection has become an important field of study, as the use of ionizing radiation for diagnosis and therapy increased along the years. According to the ALARA principles, shielding is one of the most efficient ways to minimize radiation exposure. Linear accelerators for radiotherapy treatment can lead to a considerable risk due to radiation for public and workers if proper shielding is not calculated. Mazeless rooms for LINACS are becoming more usual, as they need less space to be constructed, but, on the other hand they are more expensive. The doors of those kinds of rooms are an important point, as they will have to be thicker in mazelles room to proper shield the radiation. The NCRP 151 lays out the general considerations for the shielding calculation of standard rooms, with mazes, but there are no specific recommendations for mazeless rooms on literature. The work herein presented evaluated the absorbed dose in a room model without maze, which will be constructed soon in Brazil. The applicant calculated the thickness of the door as if it was a room with maze, and the authors used computational simulation wit MCNP code to simulate the same room, and calculated the door thickness as if it was a secondary barrier. The dose limit considered was for public occupation, 1 mSv/sem, and the energy beam was of 6 MeV. The simulated results showed that the applicant calculation thickness for the door was underestimated in 88%. The obtained results are important to establish a better methodology for shielding calculation of mazeless radiotherapy rooms that are becoming more common in Brazil. (author)

Photon dose evaluation at the entrance of radiotherapy bunkers without maze

Energy Technology Data Exchange (ETDEWEB)

Facure, Alessandro; Salata, Camila, E-mail: facure@cnen.gov.br, E-mail: camila.salata@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de janeiro, RJ (Brazil)

2017-07-01

Radiation protection has become an important field of study, as the use of ionizing radiation for diagnosis and therapy increased along the years. According to the ALARA principles, shielding is one of the most efficient ways to minimize radiation exposure. Linear accelerators for radiotherapy treatment can lead to a considerable risk due to radiation for public and workers if proper shielding is not calculated. Mazeless rooms for LINACS are becoming more usual, as they need less space to be constructed, but, on the other hand they are more expensive. The doors of those kinds of rooms are an important point, as they will have to be thicker in mazelles room to proper shield the radiation. The NCRP 151 lays out the general considerations for the shielding calculation of standard rooms, with mazes, but there are no specific recommendations for mazeless rooms on literature. The work herein presented evaluated the absorbed dose in a room model without maze, which will be constructed soon in Brazil. The applicant calculated the thickness of the door as if it was a room with maze, and the authors used computational simulation wit MCNP code to simulate the same room, and calculated the door thickness as if it was a secondary barrier. The dose limit considered was for public occupation, 1 mSv/sem, and the energy beam was of 6 MeV. The simulated results showed that the applicant calculation thickness for the door was underestimated in 88%. The obtained results are important to establish a better methodology for shielding calculation of mazeless radiotherapy rooms that are becoming more common in Brazil. (author)

Protective effect of curcumin (Curcuma longa), against aluminium toxicity: Possible behavioral and biochemical alterations in rats.

Science.gov (United States)

Kumar, Anil; Dogra, Samrita; Prakash, Atish

2009-12-28

Aluminium is a potent neurotoxin and has been associated with Alzheimer's disease (AD) causality for decades. Prolonged aluminium exposure induces oxidative stress and increases amyloid beta levels in vivo. Current treatment modalities for AD provide only symptomatic relief thus necessitating the development of new drugs with fewer side effects. The aim of the study was to demonstrate the protective effect of chronic curcumin administration against aluminium-induced cognitive dysfunction and oxidative damage in rats. Aluminium chloride (100 mg/kg, p.o.) was administered to rats daily for 6 weeks. Rats were concomitantly treated with curcumin (per se; 30 and 60 mg/kg, p.o.) daily for a period of 6 weeks. On the 21st and 42nd day of the study behavioral studies to evaluate memory (Morris water maze and elevated plus maze task paradigms) and locomotion (photoactometer) were done. The rats were sacrificed on 43rd day following the last behavioral test and various biochemical tests were performed to assess the extent of oxidative damage. Chronic aluminium chloride administration resulted in poor retention of memory in Morris water maze, elevated plus maze task paradigms and caused marked oxidative damage. It also caused a significant increase in the acetylcholinesterase activity and aluminium concentration in aluminium treated rats. Chronic administration of curcumin significantly improved memory retention in both tasks, attenuated oxidative damage, acetylcholinesterase activity and aluminium concentration in aluminium treated rats (Paluminium-induced cognitive dysfunction and oxidative damage.

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

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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.

Cognitive deficits in adult rats by lead intoxication are related with regional specific inhibition of cNOS.

Science.gov (United States)

García-Arenas, Guadalupe; Ramírez-Amaya, Victor; Balderas, Israela; Sandoval, Jimena; Escobar, Martha L; Ríos, Camilo; Bermúdez-Rattoni, Federico

2004-02-04

It is well known that lead can affect several cognitive abilities in developing animals. In this work, we investigate the effects of different sub-chronic lead doses (0, 65, 125, 250 and 500 ppm of lead acetate in their drinking water for 14 days) in the performance of male adult rats in a water maze, cue maze and inhibitory avoidance tasks. We found that the acquisition of these tasks was not affected by lead, however, the highest dosage of lead (500 ppm) impaired memory consolidation in spatial and inhibitory avoidance tasks, but not in cue maze task while the 250 ppm dose only affected retrieval of spatial memory. Additionally, hippocampal long-term potentiation (LTP) induction in the perforant path after exposing adult rats to different doses of lead was studied. LTP induction was affected in a dose-dependent manner, and treatments of 250 and 500 ppm completely blocked LTP. We investigated the effects of lead intoxication on the activity of constitutive nitric oxide synthase (cNOS) in different brain regions of adult animals. The activity of cNOS was significantly inhibited in the hippocampus and cerebellum but not in the frontal cortex and brain stem, although lead had accumulated in all brain regions. These results suggest that lead intoxication can impair memory in adult animals and this impairment might be related with region-specific effects on cNOS activity.

Where have I been? Where should I go? Spatial working memory on a radial arm maze in a rat model of depression.

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Sophie Helene Richter

Full Text Available Disturbances in cognitive functioning are among the most debilitating problems experienced by patients with major depression. Investigations of these deficits in animals help to extend and refine our understanding of human emotional disorder, while at the same time providing valid tools to study higher executive functions in animals. We employ the "learned helplessness" genetic rat model of depression in studying working memory using an eight arm radial maze procedure with temporal delay. This so-called delayed spatial win-shift task consists of three phases, training, delay and test, requiring rats to hold information on-line across a retention interval and making choices based on this information in the test phase. According to a 2×2 factorial design, working memory performance of thirty-one congenitally helpless (cLH and non-helpless (cNLH rats was tested on eighteen trials, additionally imposing two different delay durations, 30 s and 15 min, respectively. While not observing a general cognitive deficit in cLH rats, the delay length greatly influenced maze performance. Notably, performance was most impaired in cLH rats tested with the shorter 30 s delay, suggesting a stress-related disruption of attentional processes in rats that are more sensitive to stress. Our study provides direct animal homologues of clinically important measures in human research, and contributes to the non-invasive assessment of cognitive deficits associated with depression.

Effects of continuous vs. cycling estrogen replacement on the acquisition, retention and expression of place- and response-learning in the open-field tower maze.

Science.gov (United States)

Lipatova, Olga; Byrd, Dennis; Green, John T; Toufexis, Donna J

2014-10-01

Estrogen has been shown to either enhance or impair learning and memory in female rats. The use of different experimental paradigms or estrogen treatment regimens may contribute to these disparate findings. In order to assess the effect of different estradiol (E2) treatments on several aspects of cognition, we trained ovariectomized female rats with either continuous, cycling, or vehicle E2 replacement, in an open-field tower maze task (OFTM) designed to test reference memory in a low-stress environment. In addition, in order to compare two distinct learning and memory systems, rats were trained to use either a dorsolateral striatum-based response type learning or a hippocampal-based place type learning to solve the maze. Results showed that cyclic, but not continuous, E2 replacement facilitated the acquisition of spatial memory in place-learners. Neither E2 regimen affected acquisition in response-learners. Additionally, when all experimental groups were performing at asymptote, rats were evaluated for performance stability by changing the location of their start position in the OFTM. Both regimens of E2 disrupted the expression of spatial memory in place-learners following the novel start position. However, E2 replacement protected ovariectomized female rats from the disruption of memory expression following a start position change in response-learners. Additionally all experimental groups performed equally well when tested following a 21-day period during which rats were absent from the maze. These results suggest that E2 fluctuation is particularly important in the acquisition of hippocampal-mediated spatial learning, and that hippocampal-based memory may be subject to disruption following environmental change, while striatum-based memory is subject to protection. Copyright © 2014 Elsevier Inc. All rights reserved.

Testosterone influences spatial strategy preferences among adult male rats.

Science.gov (United States)

Spritzer, Mark D; Fox, Elliott C; Larsen, Gregory D; Batson, Christopher G; Wagner, Benjamin A; Maher, Jack

2013-05-01

Males outperform females on some spatial tasks, and this may be partially due to the effects of sex steroids on spatial strategy preferences. Previous work with rodents indicates that low estradiol levels bias females toward a striatum-dependent response strategy, whereas high estradiol levels bias them toward a hippocampus-dependent place strategy. We tested whether testosterone influenced the strategy preferences in male rats. All subjects were castrated and assigned to one of three daily injection doses of testosterone (0.125, 0.250, or 0.500 mg/rat) or a control group that received daily injections of the drug vehicle. Three different maze protocols were used to determine rats' strategy preferences. A low dose of testosterone (0.125 mg) biased males toward a motor-response strategy on a T-maze task. In a water maze task in which the platform itself could be used intermittently as a visual cue, a low testosterone dose (0.125 mg) caused a significant increase in the use of a cued-response strategy relative to control males. Results from this second experiment also indicated that males receiving a high dose of testosterone (0.500 mg) were biased toward a place strategy. A third experiment indicated that testosterone dose did not have a strong influence on the ability of rats to use a nearby visual cue (floating ball) in the water maze. For this experiment, all groups seemed to use a combination of place and cued-response strategies. Overall, the results indicate that the effects of testosterone on spatial strategy preference are dose dependent and task dependent. Copyright © 2013 Elsevier Inc. All rights reserved.

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

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Sajid A. Sayed

2014-09-01

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.

The planetary water drama: Dual task of feeding humanity and curbing climate change

Science.gov (United States)

Rockström, J.; Falkenmark, M.; Lannerstad, M.; Karlberg, L.

2012-08-01

This paper analyses the potential conflict between resilience of the Earth system and global freshwater requirements for the dual task of carbon sequestration to reduce CO2 in the atmosphere, and food production to feed humanity by 2050. It makes an attempt to assess the order of magnitude of the increased consumptive water use involved and analyses the implications as seen from two parallel perspectives; the global perspective of human development within a “safe operating space” with regard to the definition of the Planetary Boundary for freshwater; and the social-ecological implications at the regional river basin scale in terms of sharpening water shortages and threats to aquatic ecosystems. The paper shows that the consumptive water use involved in the dual task would both transgress the proposed planetary boundary range for global consumptive freshwater use and would further exacerbate already severe river depletion, causing societal problems related to water shortage and water allocation. Thus, strategies to rely on sequestration of CO2 as a mitigation strategy must recognize the high freshwater costs involved, implying that the key climate mitigation strategy must be to reduce emissions. The paper finally highlights the need to analyze both water and carbon tradeoffs from anticipated large scale biofuel production climate change mitigation strategy, to reveal gains and impact of this in contrast to carbon sequestration strategies.

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 -1 Anim Cogn DOI 10.1007/s10071-012-0503-0 Influence of spatial environment on maze learning in an African mole-rat Lydia du Toit ? Nigel C. Bennett ? Alecia Nickless ? Martin J. Whiting L. du Toit , A. Nickless , M. J. Whiting (email) School...

Species-relevant inescapable stress differently influences memory consolidation and retrieval of mice in a spatial radial arm maze.

Science.gov (United States)

Janitzky, K; Schwegler, H; Kröber, A; Roskoden, T; Yanagawa, Y; Linke, R

2011-05-16

Stress affects learning and there are both facilitating and impairing actions of stressors on memory processes. Here we investigated the influence of acute exposure to 2,5-dihydro-2,4,5-trimethylthiazoline (TMT), an ethological relevant stressor for rodents, on spatial memory formation and performance in a radial arm maze (RAM) task and studied TMT effects on corticosterone levels in GAD67-GFP knock-in mice and their wildtype littermates. Our results suggest that predator odor-exposure differently affects consolidation and retrieval of memory in a hippocampus-dependent spatial learning task in adult male mice, independently from their genotypes. Acute TMT-stress before retrieval facilitates performance, whereas repeated TMT-stress during consolidation exerts no influence. Additionally, we found genotype specific effects of TMT on corticosterone release. While TMT-stress tend to result in increased corticosterone release in wildtypes there was a significant decrease in transgenic mice. Taken together, these findings indicate that biologically significant predator odor-induced stress can have different actions on the strength of spatial memory formation depending on the timing with regard to memory phases. Furthermore, we suppose an impact of GABAergic mechanisms on HPA-stress axis activation to TMT resulting in absent peripheral corticosterone release of GAD67-GFP mice. Copyright © 2011 Elsevier B.V. All rights reserved.

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.

Spatial learning in the 5-HT1B receptor knockout mouse: selective facilitation/impairment depending on the cognitive demand.

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Buhot, Marie-Christine; Wolff, Mathieu; Benhassine, Narimane; Costet, Pierre; Hen, René; Segu, Louis

2003-01-01

Age-related memory decline is associated with a combined dysfunction of the cholinergic and serotonergic systems in the hippocampus and frontal cortex, in particular. The 5-HT1B receptor occupies strategic cellular and subcellular locations in these structures, where it plays a role in the modulation of ACh release. In an attempt to characterize the contribution of this receptor to memory functions, 5-HT1B receptor knockout (KO) mice were submitted to various behavioral paradigms carried out in the same experimental context (water maze), which were aimed at exposing mice to various levels of memory demand. 5-HT1BKO mice exhibited a facilitation in the acquisition of a hippocampal-dependent spatial reference memory task in the Morris water maze. This facilitation was selective of task difficulty, showing thus that the genetic inactivation of the 5-HT1B receptor is associated with facilitation when the complexity of the task is increased, and reveals a protective effect on age-related hippocampal-dependent memory decline. Young-adult and aged KO and wild-type (WT) mice were equally able to learn a delayed spatial matching-to-sample working memory task in a radial-arm water maze with short (0 or 5 min) delays. However, 5-HT1BKO mice, only, exhibited a selective memory impairment at intermediate and long (15, 30, and 60 min) delays. Treatment by scopolamine induced the same pattern of performance in wild type as did the mutation for short (5 min, no impairment) and long (60 min, impairment) delays. Taken together, these studies revealed a beneficial effect of the mutation on the acquisition of a spatial reference memory task, but a deleterious effect on a working memory task for long delays. This 5-HT1BKO mouse story highlights the problem of the potential existence of "global memory enhancers."

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

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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. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Methadone disrupts performance on the working memory version of the Morris water task.

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Hepner, Ilana J; Homewood, Judi; Taylor, Alan J

2002-05-01

The aim of the study was to examine if administration of the mu-opiate agonist methadone hydrochloride resulted in deficits in performance on the Morris water tank task, a widely used test of spatial cognition. To this end, after initial training on the task, Long-Evans rats were administered saline or methadone at either 1.25, 2.5 or 5 mg/kg ip 15 min prior to testing. The performance of the highest-dose methadone group was inferior to that of the controls on the working memory version of the Morris task. There were also differences between the groups on the reference memory version of the task, but this result cannot be considered reliable. These data show that methadone has its most profound effect on cognition in rats when efficient performance on the task requires attention to and retention of new information, in this case, the relationship between platform location and the extramaze cues.

Evaluation of the effect of acute sibutramine in female rats in the elevated T-maze and elevated plus-maze tests.

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Santos, Raliny O; de Assunção, Gabriela L M; de Medeiros, Diogo M B; de Sousa Pinto, Icaro A; de Barros, Keizianny S; Soares, Bruno L; André, Eunice; Gavioli, Elaine C; de Paula Soares-Rachetti, Vanessa

2014-02-01

Sibutramine is a serotonin and norepinephrine reuptake inhibitor indicated for the treatment of obesity. A pre-clinical study showed that acute administration of sibutramine promoted anxiolytic- and panicolytic-like effects in male rats. However, in clinical reports, sibutramine favoured the onset of panic attacks in women. In this study, the effect of sibutramine on experimental anxiety in females and the relevance of different oestrous cycle phases for this effect were analysed. In experiment 1, both male and female rats were submitted to acute intraperitoneal injection of sibutramine or vehicle 30 min. before testing in the elevated T-maze (ETM) and in the open-field test (OF). Females in the pro-oestrus (P), oestrus (E), early dioestrus (ED) and late dioestrus (LD) phases were tested in the ETM and OF (experiment 2) or in the elevated plus-maze (EPM) 30 min. after the injection of sibutramine. Sibutramine impaired the escape response in the ETM in both males and females. This effect was observed for P, E and ED, but not for LD females. Sibutramine altered neither the inhibitory avoidance in the ETM nor the behaviour of females in the EPM. Thus, sibutramine promoted a panicolytic-like effect in female rats cycling at P, E and ED, but not in the LD phase and did not alter behaviours related to anxiety in both ETM and EPM. Considering that pre-clinical studies aiming the screening of anxiolytic drugs employ male rodents, data here obtained reinforce the importance of better understanding the effects of drugs in females. © 2013 Nordic Pharmacological Society. Published by John Wiley & Sons Ltd.

Enhancement of radial maze performances in CD1 mice after prenatal exposure to oxiracetam: possible role of sustained investigative responses developed during ontogeny.

Science.gov (United States)

Ammassari-Teule, M; D'Amato, F R; Sansone, M; Oliverio, A

1988-01-01

A longitudinal study aimed at analyzing the behavioral effects of prenatal exposure to the nootropic compound oxiracetam was carried out in CD1 mice. Two groups of females were injected either with oxiracetam or saline from the beginning of pregnancy until parturition. Examination of pups from birth until the first month of age revealed no-influence of the treatment on litter size, body weights, sensory motor reflexes and motility. When placed in the open field at one month of age, mice born by mothers exposed to oxiracetam displayed more self grooming and spent less time in freezing than control mice. Prenatally treated mice were then found more interactive with their environment since the introduction of a novel object in the open field was followed by increased ambulation and higher sniffing object and rearing object scores. At three months of age, mice from both groups were tested in a radial six-arm maze task. Choice accuracy was significantly higher in prenatally treated mice which also tended to optimize their exploratory sequences by frequently running the maze in a clock-wise fashion. These results suggest that the better learning performances observed in the experimental group could be viewed as a consequence of an enhanced cognitive development based upon the higher rate of interactions with the environment shown by prenatally treated mice during ontogeny.

The Scaling of Water Governance Tasks: A Comparative Federal Analysis of the European Union and Australia

Science.gov (United States)

Benson, David; Jordan, Andrew

2010-07-01

Conflicts over how to “scale” policy-making tasks have characterized environmental governance since time immemorial. They are particularly evident in the area of water policy and raise important questions over the democratic legitimacy, economic efficiency and effectiveness of allocating (or “scaling”) tasks to some administrative levels as opposed to others. This article adopts a comparative federalism perspective to assess the “optimality” of scaling—either upward or downward—in one issue area, namely coastal recreational water quality. It does so by comparing the scaling of recreational water quality tasks in the European Union (EU) and Australia. It reveals that the two systems have adopted rather different approaches to scaling and that this difference can partly be accounted for in federal theoretical terms. However, a much greater awareness of the inescapably political nature of scaling processes is nonetheless required. Finally, some words of caution are offered with regard to transferring policy lessons between these two jurisdictions.

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. Copyright © 2010 Elsevier B.V. All rights reserved.

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

Detecting spatial memory deficits beyond blindness in tg2576 Alzheimer mice.

Science.gov (United States)

Yassine, Nour; Lazaris, Anelise; Dorner-Ciossek, Cornelia; Després, Olivier; Meyer, Laurence; Maitre, Michel; Mensah-Nyagan, Ayikoe Guy; Cassel, Jean-Christophe; Mathis, Chantal

2013-03-01

The retinal degeneration Pde6b(rd1) (rd) mutation can be a major pitfall in behavioral studies using tg2576 mice bred on a B6:SJL genetic background, 1 of the most widely used models of Alzheimer's disease. After a pilot study in wild type mice, performance of 8- and 16-month-old tg2576 mice were assessed in several behavioral tasks with the challenge of selecting 1 or more task(s) showing robust memory deficits on this genetic background. Water maze acquisition was impossible in rd homozygotes, whereas Y-maze alternation, object recognition, and olfactory discrimination were unaffected by both the transgene and the rd mutation. Spatial memory retention of 8- and 16-month-old tg2576 mice, however, was dramatically affected independently of the rd mutation when mice had to recognize a spatial configuration of objects or to perform the Barnes maze. Thus, the latter tasks appear extremely useful to evaluate spatial memory deficits and to test cognitive therapies in tg2576 mice and other mouse models bred on a background susceptible to visual impairment. Copyright © 2013 Elsevier Inc. All rights reserved.

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.

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

the opportunity to explore the entire maze immediately before the free-choice challenge after 200 forced-choice trials, this resulted in a large variation in the choice pattern of the individual rats, and a subgroup of rats choose the newly opened maze arm in 95-100% of the 20 free-choice trials....

[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.

Gaze-informed, task-situated representation of space in primate hippocampus during virtual navigation

Science.gov (United States)

Wirth, Sylvia; Baraduc, Pierre; Planté, Aurélie; Pinède, Serge; Duhamel, Jean-René

2017-01-01

To elucidate how gaze informs the construction of mental space during wayfinding in visual species like primates, we jointly examined navigation behavior, visual exploration, and hippocampal activity as macaque monkeys searched a virtual reality maze for a reward. Cells sensitive to place also responded to one or more variables like head direction, point of gaze, or task context. Many cells fired at the sight (and in anticipation) of a single landmark in a viewpoint- or task-dependent manner, simultaneously encoding the animal’s logical situation within a set of actions leading to the goal. Overall, hippocampal activity was best fit by a fine-grained state space comprising current position, view, and action contexts. Our findings indicate that counterparts of rodent place cells in primates embody multidimensional, task-situated knowledge pertaining to the target of gaze, therein supporting self-awareness in the construction of space. PMID:28241007

Relations between open-field, elevated plus-maze, and emergence tests as displayed by C57/BL6J and BALB/c mice.

Science.gov (United States)

Lalonde, R; Strazielle, C

2008-06-15

The relations between open-field, elevated plus-maze, and emergence tests were examined in two strains of mice. In the open-field, C57BL/6J mice had more ambulatory movements and rears but not stereotyped movements relative to BALB/c. In addition, C57BL/6J mice entered more often than BALB/c into enclosed and open arms of the elevated plus-maze. When placed inside a large enclosure, C57BL/6J mice emerged more quickly than BALB/c from a small toy object. In the entire series of mice, ambulation and rears in the open-field were linearly correlated with open and enclosed arm visits in the elevated plus-maze. Ambulatory movements and rears were also correlated with emergence latencies. In contrast, stereotyped movements were correlated with emergence latencies, but not with any elevated plus-maze value. These results specify the extent and limits of association between the three tests.

GABA receptors in the region of the dorsomedial hypothalamus of rats regulate anxiety in the elevated plus-maze test. II. Physiological measures.

Science.gov (United States)

Shekhar, A; Sims, L S; Bowsher, R R

1993-11-05

In the previous report, we had shown that blockade and enhancement of GABAA receptors in the DMH of rats increased or decreased the level of anxiety, respectively, as measured by the elevated plus-maze test. The present study was conducted to assess the effects of enhancing GABAA neurotransmission in the DMH of rats on the physiological concomitants of anxiety such as increases in heart rate (HR), blood pressure (BP) and plasma norepinephrine (NE) levels while the animals were placed on the elevated plus-maze. Male Sprague-Dawley rats were equipped with arterial and venous catheters and stereotaxically implanted with microinjection cannulae in the cardiostimulatory region of the DMH where injection of bicuculline methiodide (BMI) elicited increases in heart rate under anesthesia. After recovery, rats were injected with either saline or the GABAA agonist muscimol and their HR, BP and plasma NE responses were measured when confined in the open or the closed arm of the elevated plus-maze. Injection of muscimol into the DMH reduced the increases seen in HR, BP and plasma NE when the rats were confined to either the closed or the open arms in addition to decreasing 'anxiety' in the plus-maze. Injection of muscimol into the areas of the hypothalamus surrounding the DMH did not significantly affect the changes in HR, BP and plasma NE in the plus-maze. Blocking the changes in HR and BP elicited by microinjecting GABAergic drugs into the DMH of rats, with systemic injections of a combination of atropine and the beta-blocker atenolol, did not block the behavioral effects of the GABAergic drugs in the plus-maze test.

Glucocorticoid enhancement of dorsolateral striatum-dependent habit memory requires concurrent noradrenergic activity.

Science.gov (United States)

Goodman, J; Leong, K-C; Packard, M G

2015-12-17

Previous findings indicate that post-training administration of glucocorticoid stress hormones can interact with the noradrenergic system to enhance consolidation of hippocampus- or amygdala-dependent cognitive/emotional memory. The present experiments were designed to extend these findings by examining the potential interaction of glucocorticoid and noradrenergic mechanisms in enhancement of dorsolateral striatum (DLS)-dependent habit memory. In experiment 1, different groups of adult male Long-Evans rats received training in two DLS-dependent memory tasks. In a cued water maze task, rats were released from various start points and were reinforced to approach a visibly cued escape platform. In a response-learning version of the water plus-maze task, animals were released from opposite starting positions and were reinforced to make a consistent egocentric body-turn to reach a hidden escape platform. Immediately post-training, rats received peripheral injections of the glucocorticoid corticosterone (1 or 3 mg/kg) or vehicle solution. In both tasks, corticosterone (3 mg/kg) enhanced DLS-dependent habit memory. In experiment 2, a separate group of animals received training in the response learning version of the water plus-maze task and were given peripheral post-training injections of corticosterone (3 mg/kg), the β-adrenoreceptor antagonist propranolol (3 mg/kg), corticosterone and propranolol concurrently, or control vehicle solution. Corticosterone injections again enhanced DLS-dependent memory, and this effect was blocked by concurrent administration of propranolol. Propranolol administration by itself (3 mg/kg) did not influence DLS-dependent memory. Taken together, the findings indicate an interaction between glucocorticoid and noradrenergic mechanisms in DLS-dependent habit memory. Propranolol administration may be useful in treating stress-related human psychopathologies associated with a dysfunctional DLS-dependent habit memory system. Copyright © 2015

Exposure to predator odor influences the relative use of multiple memory systems: role of basolateral amygdala.

Science.gov (United States)

Leong, Kah-Chung; Packard, Mark G

2014-03-01

In a dual-solution plus-maze task in which both hippocampus-dependent place learning and dorsolateral striatal-dependent response learning provide an adequate solution, the relative use of multiple memory systems can be influenced by emotional state. Specifically, pre-training peripheral or intra-basolateral (BLA) administration of anxiogenic drugs result in the predominant use of response learning. The present experiments were designed to extend these findings by examining whether exposure to a putatively ethologically valid stressor would also produce a predominant use of response learning. In experiment 1, adult male Long-Evans rats were exposed to either a predator odor (trimethylthiazoline [TMT], a component of fox feces) or distilled water prior to training in a dual-solution water plus maze task. On a probe trial 24h following task acquisition, rats previously exposed to TMT predominantly displayed response learning relative to control animals. In experiment 2, rats trained on a single-solution plus maze task that required the use of response learning displayed enhanced acquisition following pre-training TMT exposure. In experiment 3, rats exposed to TMT or distilled water were trained in the dual-solution task and received post-training intra-BLA injections of the sodium channel blocker bupivacaine (1.0% solution, 0.5 μl) or saline. Relative to control animals, rats exposed to TMT predominantly displayed response learning on the probe trial, and this effect was blocked by neural inactivation of the BLA. The findings indicate that (1) the use of dorsal striatal-dependent habit memory produced by emotional arousal generalizes from anxiogenic drug administration to a putatively ecologically valid stressor (i.e. predator odor), and (2) the BLA mediates the modulatory effect of exposure to predator odor on the relative use of multiple memory systems. Copyright © 2013 Elsevier Inc. All rights reserved.

Shielding of radiation fields generated by 252Cf in a concrete maze. Part 2 -- Simulation

International Nuclear Information System (INIS)

Fasso, A.; Ipe, N.E.; Reyna, A.

1998-03-01

A streaming experiment performed in a concrete maze of shape and size typical of a radiotherapy room was simulated with the Monte Carlo program FLUKA. The purpose of the calculation was to test the performance of the code in the low energy neutron range, and at the same time to provide additional information which could help in optimizing shielding of medical facilities. Instrument responses were calculated at different maze locations for several experimental configurations and were compared with measurements. In addition, neutron and gamma fluence, ambient dose equivalent and effective dose were calculated at the same positions. Both sources used in the experiment, namely a bare 252 Cf source and one shielded by a tungsten shell 5 cm thick, were considered in the simulation

Gazing toward humans: a study on water rescue dogs using the impossible task paradigm.

Science.gov (United States)

D'Aniello, Biagio; Scandurra, Anna; Prato-Previde, Emanuela; Valsecchi, Paola

2015-01-01

Various studies have assessed the role of life experiences, including learning opportunities, living conditions and the quality of dog-human relationships, in the use of human cues and problem-solving ability. The current study investigates how and to what extent training affects the behaviour of dogs and the communication of dogs with humans by comparing dogs trained for a water rescue service and untrained pet dogs in the impossible task paradigm. Twenty-three certified water rescue dogs (the water rescue group) and 17 dogs with no training experience (the untrained group) were tested using a modified version of the impossible task described by Marshall-Pescini et al. in 2009. The results demonstrated that the water rescue dogs directed their first gaze significantly more often towards the owner and spent more time gazing toward two people compared to the untrained pet dogs. There was no difference between the dogs of the two groups as far as in the amount of time spent gazing at the owner or the stranger; neither in the interaction with the apparatus attempting to obtain food. The specific training regime, aimed at promoting cooperation during the performance of water rescue, could account for the longer gazing behaviour shown toward people by the water rescue dogs and the priority of gazing toward the owner. Copyright © 2014 Elsevier B.V. All rights reserved.

The spatial distribution of errors made by rats in Hebb-Williams type mazes in relation to the spatial properties of the blind alleys

NARCIS (Netherlands)

Boer, S. de; Bohus, B.

The various configurations in series of Hebb-Williams type of mazes, which are used to measure problem solving behaviour in rats, differ markedly in structure. The relationship between error behaviour and spatial maze structure in control rats tested in a number of pharmacological experiments is

Agmatine protects against intracerebroventricular streptozotocin-induced water maze memory deficit, hippocampal apoptosis and Akt/GSK3β signaling disruption.

Science.gov (United States)

Moosavi, Maryam; Zarifkar, Amir Hossein; Farbood, Yaghoub; Dianat, Mahin; Sarkaki, Alireza; Ghasemi, Rasoul

2014-08-05

Centrally administered streptozotocin (STZ), is known to cause Alzheimer׳s like memory deterioration. It mainly affects insulin signaling pathways such as PI3/Akt and GSK-3β which are involved in cell survival. Previous studies indicate that STZ increases the ratio of Bax/Bcl-2 and thereby induces caspase-3 activation and apoptosis. Agmatine, a polyamine derived from l-arginine decarboxylation, is recently shown to exert some neuroprotective effects. This study aimed to assess if agmatine reverses STZ-induced memory deficits, hippocampal Akt/GSK-3β signaling disruption and caspase-3 activation. Adult male Sprague-Dawely rats weighing 200-250 g were used. The canules were implanted bilaterally into lateral ventricles. STZ was administered on days 1 and 3 (3 mg/kg) and agmatine treatment (40 or 80 mg/kg) was started from day 4 and continued in an every other day manner till day 14. The animal׳s learning and memory capability was assessed on days 15-18 using Morris water maze. After complement of behavioral studies the hippocampi was isolated and the amounts of hippocampal cleaved caspase-3 (the landmark of apoptosis), Bax/Bcl-2 ratio, total and phosphorylated forms of GSK-3β and Akt were analyzed by western blot. The results showed that agmatine in 80 but not 40 mg/kg reversed the memory deterioration induced by STZ. Western blot analysis revealed that STZ prompted elevation of caspase-3; Bax/Bcl-2 ratio and disrupted Akt/GSK-3β signaling in the hippocampus. Agmatine treatment prevented apoptosis and Akt/GSK-3β signaling impairment induced by STZ. This study disclosed that agmatine treatment averts not only STZ-induced memory deterioration but also hippocampal apoptosis and Akt/GSK-3β signaling disruption. Copyright © 2014 Elsevier B.V. All rights reserved.

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…

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.

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.

Contributions of sex, testosterone, and androgen receptor CAG repeat number to virtual Morris water maze performance.

Science.gov (United States)

Nowak, Nicole T; Diamond, Michael P; Land, Susan J; Moffat, Scott D

2014-03-01

The possibility that androgens contribute to the male advantage typically found on measures of spatial cognition has been investigated using a variety of approaches. To date, evidence to support the notion that androgens affect spatial cognition in healthy young adults is somewhat equivocal. The present study sought to clarify the association between testosterone (T) and spatial performance by extending measurements of androgenicity to include both measures of circulating T as well as an androgen receptor-specific genetic marker. The aims of this study were to assess the contributions of sex, T, and androgen receptor CAG repeat number (CAGr) on virtual Morris water task (vMWT) performance in a group of healthy young men and women. The hypothesis that men would outperform women on vMWT outcomes was supported. Results indicate that CAGr may interact with T to impact navigation performance and suggest that consideration of androgen receptor sensitivity is an important consideration in evaluating hormone-behavior relationships. Copyright © 2013 Elsevier Ltd. All rights reserved.

Environmental health sciences center task force review on halogenated organics in drinking water.

Science.gov (United States)

Deinzer, M; Schaumburg, F; Klein, E

1978-06-01

The disinfection of drinking water by chlorination has in recent years come under closer scrutiny because of the potential hazards associated with the production of stable chlorinated organic chemicals. Organic chemical contaminants are common to all water supplies and it is now well-established that chlorinated by-products are obtained under conditions of disinfection, or during tertiary treatment of sewage whose products can ultimately find their way into drinking water supplies. Naturally occurring humic substances which are invariably present in drinking waters are probably the source of chloroform and other halogenated methanes, and chloroform has shown up in every water supply investigated thus far.The Environmental Protection Agency is charged with the responsibility of assessing the public health effects resulting from the consumption of contaminated drinking water. It has specifically undertaken the task of determining whether organic contaminants or their chlorinated derivatives have a special impact, and if so, what alternatives there are to protect the consumer against bacterial and viral diseases that are transmitted through infected drinking waters. The impetus to look at these chemicals is not entirely without some prima facie evidence of potential trouble. Epidemiological studies suggested a higher incidence of cancer along the lower Mississippi River where the contamination from organic chemicals is particularly high. The conclusions from these studies have, to be sure, not gone unchallenged.The task of assessing the effects of chemicals in the drinking water is a difficult one. It includes many variables, including differences in water supplies and the temporal relationship between contamination and consumption of the finished product. It must also take into account the relative importance of the effects from these chemicals in comparison to those from occupational exposure, ingestion of contaminated foods, inhalation of polluted air, and many

Preoperative study of the surface ECG for the prognosis of atrial fibrillation maze surgery outcome at discharge

International Nuclear Information System (INIS)

Hernández, Antonio; Rieta, José Joaquín; Alcaraz, Raúl; Hornero, Fernando

2014-01-01

The Cox-maze surgery is an effective procedure for terminating atrial fibrillation (AF) in patients requiring open-heart surgery associated with another heart disease. After the intervention, regardless of the patient's rhythm, all are treated with oral anticoagulants and antiarrhythmic drugs prior to discharge. Furthermore, patients maintaining AF before discharge could also be treated with electrical cardioversion (ECV). In view of this, a preoperative prognosis of the patient's rhythm at discharge would be helpful for optimizing drug therapy planning as well as for advancing ECV therapy. This work analyzes 30 preoperative electrocardiograms (ECGs) from patients suffering from AF in order to predict the Cox-maze surgery outcome at discharge. Two different characteristics of the AF pattern have been studied. On the one hand, the atrial activity (AA) organization, which provides information about the number of propagating wavelets in the atria, was investigated. AA organization has been successfully used in previous studies related to spontaneous reversion of paroxysmal AF and to the outcome of ECV. To assess organization, the dominant atrial frequency (DAF) and sample entropy (SampEn) have been computed. On the other hand, the second characteristic studied was the fibrillatory wave (f-wave) amplitude, which has been demonstrated to be a valuable indicator of the Cox-maze surgery outcome in previous studies. Moreover, this parameter has been obtained through a new methodology, based on computing the f-wave average power (fWP). Finally, all the computed indices were combined in a decision tree in order to improve prediction capability. Results for the DAF yielded a sensitivity (Se), a specificity (Sp) and an accuracy (Acc) of 61.54%, 82.35% and 73.33%, respectively. For SampEn the values were 69.23%, 76.00% and 73.33%, respectively, and for fWP they were 92.31%, 82.35% and 86.67%, respectively. Finally, the decision tree combining the three parameters

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

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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.

Shielding of radiation fields generated by {sup 252}Cf in a concrete maze. Part 2 -- Simulation

Energy Technology Data Exchange (ETDEWEB)

Fasso, A.; Ipe, N.E.; Reyna, A. [Stanford Univ., CA (US). Stanford Linear Accelerator Center; McCall, R.C. [McCall Associates, Woodside, CA (US)

1998-03-01

A streaming experiment performed in a concrete maze of shape and size typical of a radiotherapy room was simulated with the Monte Carlo program FLUKA. The purpose of the calculation was to test the performance of the code in the low energy neutron range, and at the same time to provide additional information which could help in optimizing shielding of medical facilities. Instrument responses were calculated at different maze locations for several experimental configurations and were compared with measurements. In addition, neutron and gamma fluence, ambient dose equivalent and effective dose were calculated at the same positions. Both sources used in the experiment, namely a bare {sup 252}Cf source and one shielded by a tungsten shell 5 cm thick, were considered in the simulation.

Effects of caloric restriction on learning and recovery of a spatial task in rats exposed to acute stress

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Lamprea Rodríguez, Marisol

2009-06-01

Full Text Available The purpose of the present study was to describe the effects of caloric restriction on spatial learning and recovery in the Barnes maze in animals experimentally stressed before recovery of the spatial task. Male Wistar rats were exposed for two months to one of two conditions: ad libitum (AL or intermittent fasting (IF. Both groups were exposed then to an experimental form of acute stress, induced by movement restriction for 4 hours. IF subjects had better performance in learning tasks during the acquisition trials but required more time to complete the task after the stressor was applied. These results are discussed in light of previous data reported in the literature emphasizing differences in the instruments used to evaluate spatial learning and its interaction with experimentally induced stress.

Effects of Ginsenoside Rg1 on Learning and Memory in a Reward-directed Instrumental Conditioning Task in Chronic Restraint Stressed Rats.

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Kezhu, Wang; Pan, Xu; Cong, Lu; Liming, Dong; Beiyue, Zhang; Jingwei, Lu; Yanyan, Yang; Xinmin, Liu

2017-01-01

Ginsenoside Rg1 is one of the major active ingredients of Panax ginseng and has showed notable improving learning and memory effects in several behavioral tasks, such as water maze, shuttle-box, and step-through, based on avoidance. However, there was no report about the role of Rg1 on the performance of reward-directed instrumental conditioning, which could reflect the adaptive capacity to ever-changing environments. Thus, in this study, the reward devaluation test and conditional visual discrimination task were conducted to study the ameliorating effects of Rg1 on cognitive deficits, especially the loss of adaptation capacity in chronic restraint stress (CRS) rat model. Our results showed that rat subjected to CRS became insensitive to the changes in outcome value, and it significantly harmed the rat's performance in conditional visual discrimination task. Moreover, the levels of BDNF, TrkB, and Erk phosphorylation were decreased in the prefrontal cortex of CRS rats. However, these changes were effectively reversed by Rg1 (5 and 10 mg/kg, i.p.). Therefore, it demonstrated that Rg1 has a good ability to improve learning and memory and also ameliorate impaired adaptive capacity induced by CRS. This amelioration effect of Rg1 might be mediated partially by BDNF/TrkB/Erk pathway in prefrontal cortex. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The dorsal tegmental noradrenergic projection: an analysis of its role in maze learning.

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Roberts, D C; Price, M T; Fibiger, H C

1976-04-01

The hypothesis that the noradrenergic projection from the locus coeruleus (LC) to the cerebral cortex and hippocampus is an important neural substrate for learning was evaluated. Maze performance was studied in rats receiving either electrolytic lesions of LC or 6-hydroxydopamine (6-OHDA) lesions of the dorsal tegmental noradrenergic projection. The LC lesions did not disrupt the acquisition of a running response for food reinforcement in an L-shaped runway, even though hippocampal-cortical norepinephrine (NE) was reduced to 29%. Greater telencephalic NE depletions (to 6% of control levels) produced by 6-OHDA also failed to disrupt the acquisition of this behavior or to impair the acquisition of a food-reinforced position habit in a T-maze. Neither locomotor activity nor habituation to a novel environment was affected by the 6-OHDA lesions. Rats with such lesions were, however, found to be significantly more distractible than were controls during the performance of a previously trained response. The hypothesis that telencephalic NE is of fundamental importance in learning was not supported. The data suggest that this system may participate in attentional mechanisms.

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

Science.gov (United States)

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. Copyright © 2015 Elsevier Inc. All

Learning to remember: Cognitive training-induced attenuation of age-related memory decline depends on sex and cognitive demand, and can transfer to untrained cognitive domains

Science.gov (United States)

Talboom, Joshua S.; West, Stephen G.; Engler-Chiurazzi, Elizabeth B.; Enders, Craig K.; Crain, Ian; Bimonte-Nelson, Heather A.

2014-01-01

Aging is associated with progressive changes in learning and memory. A potential approach to attenuate age-related cognitive decline is cognitive training. In this study, adult male and female rats were given either repeated exposure to a T-maze, or no exposure to any maze, and then tested on a final battery of cognitive tasks. Two groups of each sex were tested from 6-18 months old on the same T-maze; one group received a version testing spatial reference memory, and the other group received only the procedural testing components with minimal cognitive demand. Groups three and four of each sex had no maze exposure until the final battery, and were comprised of aged or young rats. The final maze battery included the practiced T-maze plus two novel tasks, one with a similar, and one with a different, memory type to the practice task. The fifth group of each sex was not maze tested, serving as an aged control for the effects of maze testing on neurotrophin protein levels in cognitive brain regions. Results showed that adult intermittent cognitive training enhanced performance on the practice task when aged in both sexes, that cognitive training benefits transferred to novel tasks only in females, and that cognitive demand was necessary for these effects since rats receiving only the procedural testing components showed no improvement on the final maze battery. Further, for both sexes, rats that showed faster learning when young demonstrated better memory when aged. Age-related increases in neurotrophin concentrations in several brain regions were revealed, which was related to performance on the training task only in females. This longitudinal study supports the tenet that cognitive training can help one remember later in life, with broader enhancements and associations with neurotrophins in females. PMID:25104561

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

International Nuclear Information System (INIS)

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

2014-01-01

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. (paper)

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.

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

Kv4.2 knockout mice display learning and memory deficits in the Lashley maze [version 1; referees: 2 approved

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Gregory D. Smith

2016-10-01

Full Text Available Background: Potassium channels have been shown to be involved in neural plasticity and learning. Kv4.2 is a subunit of the A-type potassium channel. Kv4.2 channels modulate excitability in the dendrites of pyramidal neurons in the cortex and hippocampus. Deletion of Kv4.2 results in spatial learning and conditioned fear deficits; however, previous studies have only examined deletion of Kv4.2 in aversive learning tests. Methods: For the current study, we used the Lashley maze as an appetitive learning test. We examined Kv4.2 wildtype (WT and knockout (KO mice in the Lashley maze over 4 days during adulthood. The first day consisted of habituating the mice to the maze. The mice then received five trials per day for the next 3 days. The number of errors and the time to the goal box was recorded for each trial. The goal box contained a weigh boat with an appetitive reward (gelatin with sugar. There was an intertrial interval of 15 minutes. Results: We found that Kv4.2 KO mice committed more errors across the trials compared to the WT mice p<0.001. There was no difference in the latency to find the goal box over the period. Discussion: Our finding that deletion of Kv4.2 resulted in more errors in the Lashley maze across 15 trials contribute to a growing body of evidence that Kv4.2 channels are significantly involved in learning and memory.

Kv4.2 knockout mice display learning and memory deficits in the Lashley maze [version 2; referees: 2 approved

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Gregory D. Smith

2017-02-01

Full Text Available Background: Potassium channels have been shown to be involved in neural plasticity and learning. Kv4.2 is a subunit of the A-type potassium channel. Kv4.2 channels modulate excitability in the dendrites of pyramidal neurons in the cortex and hippocampus. Deletion of Kv4.2 results in spatial learning and conditioned fear deficits; however, previous studies have only examined deletion of Kv4.2 in aversive learning tests. Methods: For the current study, we used the Lashley maze as an appetitive learning test. We examined Kv4.2 wildtype (WT and knockout (KO mice in the Lashley maze over 4 days during adulthood. The first day consisted of habituating the mice to the maze. The mice then received five trials per day for the next 3 days. The number of errors and the time to the goal box was recorded for each trial. The goal box contained a weigh boat with an appetitive reward (gelatin with sugar. There was an intertrial interval of 15 minutes. Results: We found that Kv4.2 KO mice committed more errors across the trials compared to the WT mice p<0.001. There was no difference in the latency to find the goal box over the period. Discussion: Our finding that deletion of Kv4.2 resulted in more errors in the Lashley maze across 15 trials contribute to a growing body of evidence that Kv4.2 channels are significantly involved in learning and memory.

Selective immunotoxic lesions of basal forebrain cholinergic cells: effects on learning and memory in rats.

Science.gov (United States)

Baxter, Mark G; Bucci, David J; Gorman, Linda K; Wiley, Ronald G; Gallagher, Michela

2013-10-01

Male Long-Evans rats were given injections of either 192 IgG-saporin, an apparently selective toxin for basal forebrain cholinergic neurons (LES), or vehicle (CON) into either the medial septum and vertical limb of the diagonal band (MS/VDB) or bilaterally into the nucleus basalis magnocellularis and substantia innominata (nBM/SI). Place discrimination in the Morris water maze assessed spatial learning, and a trial-unique matching-to-place task in the water maze assessed memory for place information over varying delays. MS/VDB-LES and nBM/SI-LES rats were not impaired relative to CON rats in acquisition of the place discrimination, but were mildly impaired relative to CON rats in performance of the memory task even at the shortest delay, suggesting a nonmnemonic deficit. These results contrast with effects of less selective lesions, which have been taken to support a role for basal forebrain cholinergic neurons in learning and memory. 2013 APA, all rights reserved

Ameliorating effect of new constituents from the hooks of Uncaria rhynchophylla on scopolamine-induced memory impairment.

Science.gov (United States)

Shin, Suk-Chul; Lee, Dong-Ung

2013-07-01

To study the chemical constituents and their anti-amnesic effect from the hooks of Uncaria rhynchophylla. The isolation of compounds was performed by chromatographic techniques and their structures were identified on the basis of spectral analysis. Their ameliorating effects on scopolamine-induced memory impairment in vivo using a Morris water-maze task and passive avoidance task system were evaluated. Activity-guided fractionation of the total extracts resulted in the isolation of four constituents, trans-anethole (1), p-anisaldehyde (2), estragole (3), and 3-oxo-olean-12-en-28-oic acid (4), which were found for the first time from this plant. Compound 1 exhibited a better memory enhancing effect than tacrine, a positive agent, at the same dose in the passive avoidance test and a similar property in the water-maze test, and its action may be mediated, in part, by the acetylcholine enhancing cholinergic nervous system. Copyright © 2013 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

High-sucrose diets in male rats disrupt aspects of decision making tasks, motivation and spatial memory, but not impulsivity measured by operant delay-discounting.

Science.gov (United States)

Wong, Alanna; Dogra, Vimi R; Reichelt, Amy C

2017-06-01

Excessive consumption of sugar sweetened drinks is proposed to produce functional changes in the hippocampus and prefrontal cortex, leading to perturbations in behavioural control. Impairments in behavioural control have been observed in obese people on tasks that involve making choices, including delay-discounting, indicative of increased impulsivity. In this study we examined the impact of 2h daily access to 10% sucrose (or no sucrose in controls) in young male rats on behavioural tasks reliant on hippocampal function including delay-discounting, T-maze forced choice alternation and place recognition memory, as well as progressive ratio to measure motivation. We observed deficits in place recognition memory and T-maze forced choice alternation, indicative of hippocampal deficits in rats with a history of sucrose consumption. Moreover, rats with a history of sucrose consumption were less motivated to lever press for rewards on a progressive ratio schedule. However, rats with a history of sucrose consumption performed equally to control animals during the delay-discounting task, suggesting that they discounted for reward size over a delay in a manner comparable to control animals. These findings indicate that high-sucrose diets impact on spatial and working memory processes, but do not induce impulsive-like choice behaviours in rats, suggesting that unhealthy diet choices may not influence this aspect of decision-making behaviour. Copyright © 2017 Elsevier B.V. All rights reserved.

Easy rider: monkeys learn to drive a wheelchair to navigate through a complex maze.

Science.gov (United States)

Etienne, Stephanie; Guthrie, Martin; Goillandeau, Michel; Nguyen, Tho Hai; Orignac, Hugues; Gross, Christian; Boraud, Thomas

2014-01-01

The neurological bases of spatial navigation are mainly investigated in rodents and seldom in primates. The few studies led on spatial navigation in both human and non-human primates are performed in virtual, not in real environments. This is mostly because of methodological difficulties inherent in conducting research on freely-moving monkeys in real world environments. There is some incertitude, however, regarding the extrapolation of rodent spatial navigation strategies to primates. Here we present an entirely new platform for investigating real spatial navigation in rhesus monkeys. We showed that monkeys can learn a pathway by using different strategies. In these experiments three monkeys learned to drive the wheelchair and to follow a specified route through a real maze. After learning the route, probe tests revealed that animals successively use three distinct navigation strategies based on i) the place of the reward, ii) the direction taken to obtain reward or iii) a cue indicating reward location. The strategy used depended of the options proposed and the duration of learning. This study reveals that monkeys, like rodents and humans, switch between different spatial navigation strategies with extended practice, implying well-conserved brain learning systems across different species. This new task with freely driving monkeys provides a good support for the electrophysiological and pharmacological investigation of spatial navigation in the real world by making possible electrophysiological and pharmacological investigations.

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

Advantages of Task-Specific Multi-Objective Optimisation in Evolutionary Robotics.

Science.gov (United States)

Trianni, Vito; López-Ibáñez, Manuel

2015-01-01

The application of multi-objective optimisation to evolutionary robotics is receiving increasing attention. A survey of the literature reveals the different possibilities it offers to improve the automatic design of efficient and adaptive robotic systems, and points to the successful demonstrations available for both task-specific and task-agnostic approaches (i.e., with or without reference to the specific design problem to be tackled). However, the advantages of multi-objective approaches over single-objective ones have not been clearly spelled out and experimentally demonstrated. This paper fills this gap for task-specific approaches: starting from well-known results in multi-objective optimisation, we discuss how to tackle commonly recognised problems in evolutionary robotics. In particular, we show that multi-objective optimisation (i) allows evolving a more varied set of behaviours by exploring multiple trade-offs of the objectives to optimise, (ii) supports the evolution of the desired behaviour through the introduction of objectives as proxies, (iii) avoids the premature convergence to local optima possibly introduced by multi-component fitness functions, and (iv) solves the bootstrap problem exploiting ancillary objectives to guide evolution in the early phases. We present an experimental demonstration of these benefits in three different case studies: maze navigation in a single robot domain, flocking in a swarm robotics context, and a strictly collaborative task in collective robotics.

Advantages of Task-Specific Multi-Objective Optimisation in Evolutionary Robotics.

Directory of Open Access Journals (Sweden)

Vito Trianni

Full Text Available The application of multi-objective optimisation to evolutionary robotics is receiving increasing attention. A survey of the literature reveals the different possibilities it offers to improve the automatic design of efficient and adaptive robotic systems, and points to the successful demonstrations available for both task-specific and task-agnostic approaches (i.e., with or without reference to the specific design problem to be tackled. However, the advantages of multi-objective approaches over single-objective ones have not been clearly spelled out and experimentally demonstrated. This paper fills this gap for task-specific approaches: starting from well-known results in multi-objective optimisation, we discuss how to tackle commonly recognised problems in evolutionary robotics. In particular, we show that multi-objective optimisation (i allows evolving a more varied set of behaviours by exploring multiple trade-offs of the objectives to optimise, (ii supports the evolution of the desired behaviour through the introduction of objectives as proxies, (iii avoids the premature convergence to local optima possibly introduced by multi-component fitness functions, and (iv solves the bootstrap problem exploiting ancillary objectives to guide evolution in the early phases. We present an experimental demonstration of these benefits in three different case studies: maze navigation in a single robot domain, flocking in a swarm robotics context, and a strictly collaborative task in collective robotics.

3α-androstanediol, but not testosterone, attenuates age-related decrements in cognitive, anxiety, and depressive behavior of male rats

Directory of Open Access Journals (Sweden)

Cheryl A Frye

2010-04-01

Full Text Available Some hippocampally-influenced affective and/or cognitive processes decline with aging. The role of androgens in this process is of interest. Testosterone (T is aromatized to estrogen, and reduced to dihydrotestosterone (DHT, which is converted to 5α-androstane, 3α, 17α-diol (3α-diol. To determine the extent to which some age-related decline in hippocampally-influenced behaviors may be due to androgens, we examined the effects of variation in androgen levels due to age, gonadectomy, and androgen replacement on cognitive (inhibitory avoidance, Morris water maze and affective (defensive freezing, forced swim behavior among young (4-months, middle-aged (13-months, and aged (24-months male rats. Plasma and hippocampal levels of androgens were determined. In experiment 1, comparisons were made between 4-, 13-, and 24-month old rats that were intact or gonadectomized (GDX and administered a T-filled or empty silastic capsule. There was age-related decline in performance of the inhibitory avoidance, water maze, defensive freezing, and forced swim tasks, and hippocampal 3α-diol levels. Chronic, long-term (1-4 weeks T-replacement reversed the effects of GDX in 4- and 13-month old, but not 24-month old, rats in the inhibitory avoidance task. Experiments 2 and 3 assessed whether acute subcutaneous T or 3α-diol, respectively, could reverse age-associated decline in performance. 3α-diol, but not T, compared to vehicle, improved performance in the inhibitory avoidance, water maze, forced swim, and defensive freezing tasks, irrespective of age. Thus, age is associated with a decrease in 3α-diol production and 3α-diol administration reinstates cognitive and affective performance of aged male rats.

Re-thinking the role of the dorsal striatum in egocentric/response strategy.

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Botreau, Fanny; Gisquet-Verrier, Pascale

2010-01-01

Rats trained in a dual-solution cross-maze task, which can be solved by place and response strategies, predominantly used a response strategy after extensive training. This paper examines the involvement of the medial and lateral dorsal striatum (mDS and lDS) in the choice of these strategies after partial and extensive training. Our results show that rats with lDS and mDS lesions used mainly a response strategy from the early phase of training. We replicated these unexpected data in rats with lDS lesions and confirmed their tendency to use the response strategy in a modified cross-maze task. When trained in a dual-solution water-maze task, however, control and lesioned rats consistently used a place strategy, demonstrating that lDS and mDS lesioned rats can use a place strategy and that the shift towards a response strategy did not systematically result from extensive training. The present data did not show any clear dissociation between the mDS and lDS in dual solution tasks. They further indicate that the dorsal striatum seems to determine the strategies adopted in a particular context but cannot be considered as a neural support for the response memory system. Accordingly, the role of the lateral and medial part of the dorsal striatum in egocentric/response memory should be reconsidered.

Dose-response effects of systemic anandamide administration in mice sequentially submitted to the open field and elevated plus-maze tests.

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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.

Lithium ameliorates open-field and elevated plus maze behaviors, and brain phospho-glycogen synthase kinase 3-beta expression in fragile X syndrome model mice.

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Chen, Xi; Sun, Weiwen; Pan, Ying; Yang, Quan; Cao, Kaiyi; Zhang, Jin; Zhang, Yizhi; Chen, Mincong; Chen, Feidi; Huang, Yueling; Dai, Lijun; Chen, Shengqiang

2013-10-01

To investigate whether lithium modifies open-field and elevated plus maze behavior, and brain phospho-glycogen synthase kinase 3 (P-GSK3beta) expression in Fmr1 knockout mice. One hundred and eighty FVB mice, including knockout and wild type, with an age of 30 days were used. An open-field and elevated plus maze was utilized to test behavior, while western blot was used to measure the P-GSK3beta expression. Six groups were formed: control (saline), lithium chloride 30, 60, 90, 120, and 200 mg/kg. The experiments were carried out in the Institute of Neuroscience, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China between January and June 2012. Lithium significantly decreased total distance, crossing, central area time, and center entry in the open-field test (popen-arm tracking, open-arm entry, and open-arm time in the elevated plus maze (popen-field and elevated plus maze behaviors of Fmr1 knockout mice. This effect may be related to its enhancement of P-GSK3beta expression. Our findings suggest that lithium might have a therapeutic effect in fragile X syndrome.

Effect of ethanolic extract of Carpolobia lutea G. Don (polygalaceae ...

African Journals Online (AJOL)

The effect of the extract on cognitive memory was investigated using the Novel Object recognition task (NORT) while the effect on visuospatial learning and memory was studied using the Morris Water maze (MWM). The results obtained in the NORT show that the index of habituation was significantly lower following acute ...

Factors moderating blocking in human place learning: the role of task instructions.

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Hardt, Oliver; Hupbach, Almut; Nadel, Lynn

2009-02-01

Cognitive map theory assumes that novel environmental information is automatically incorporated into existing cognitive maps as a function of exploration. Reports of blocking in place learning cast doubt on this claim. In these studies, subjects were first trained to find a place, using a set of landmarks (Set A). Then novel landmarks (Set B) were added for additional trials. Subsequent removal of the Set A landmarks showed that the novel landmarks alone were insufficient for successful navigation. We investigated whether instructing human subjects to explore the environment can moderate blocking. First, we demonstrated that blocking is absent in a computer implementation of the Morris water maze (MWM) in which subjects are instructed to explore. We then studied why others found blocking in a different MWM implementation, in which the task instructions did not suggest exploration. In experiments that faithfully replicated this MWM variant, we found that subjects did not acquire cognitive maps and that blocking was attenuated when instructions were provided that encouraged exploration. Together, these findings indicate that blocking in human place learning may reflect a performance deficit, not a learning deficit, and that instructions can moderate blocking. Our results thus support the automatic update assumption of cognitive map theory.

Overshadowing of geometric cues by a beacon in a spatial navigation task.

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Redhead, Edward S; Hamilton, Derek A; Parker, Matthew O; Chan, Wai; Allison, Craig

2013-06-01

In three experiments, we examined whether overshadowing of geometric cues by a discrete landmark (beacon) is due to the relative saliences of the cues. Using a virtual water maze task, human participants were required to locate a platform marked by a beacon in a distinctively shaped pool. In Experiment 1, the beacon overshadowed geometric cues in a trapezium, but not in an isosceles triangle. The longer escape latencies during acquisition in the trapezium control group with no beacon suggest that the geometric cues in the trapezium were less salient than those in the triangle. In Experiment 2, we evaluated whether generalization decrement, caused by the removal of the beacon at test, could account for overshadowing. An additional beacon was placed in an alternative corner. For the control groups, the beacons were identical; for the overshadow groups, they were visually unique. Overshadowing was again found in the trapezium. In Experiment 3, we tested whether the absence of overshadowing in the triangle was due to the geometric cues being more salient than the beacon. Following training, the beacon was relocated to a different corner. Participants approached the beacon rather than the trained platform corner, suggesting that the beacon was more salient. These results suggest that associative processes do not fully explain cue competition in the spatial domain.

Incident report and estimates of personnel exposure for a staff present in maze corridor of linac room while radiation beam on

International Nuclear Information System (INIS)

Ravichandran, R.; Davis, C.A.; Ghamrawy, Kamal El; Arunkumar, L.S.

2007-01-01

The radiation safety features of high energy linear accelerator installations include primary and secondary barriers made of concrete (radiation bunkers), provision of maze wall for eliminating first scatter reaching the entrance door, locating room entrance perpendicular to maze corridor to reduce neutron dose. In addition, special motorized doors with lead lining and paraffin blocks, electrically interlocked to beam on-off system is provided for radiation safety. A radiation incident took place involving presence of a staff inside the Clinac 2300 CD room in September 2006 has been described

Long-term effects of chronic intermittent ethanol exposure in adolescent and adult rats: radial-arm maze performance and operant food reinforced responding.

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Mary-Louise Risher

Full Text Available Adolescence is not only a critical period of late-stage neurological development in humans, but is also a period in which ethanol consumption is often at its highest. Given the prevalence of ethanol use during this vulnerable developmental period we assessed the long-term effects of chronic intermittent ethanol (CIE exposure during adolescence, compared to adulthood, on performance in the radial-arm maze (RAM and operant food-reinforced responding in male rats.Male Sprague Dawley rats were exposed to CIE (or saline and then allowed to recover. Animals were then trained in either the RAM task or an operant task using fixed- and progressive- ratio schedules. After baseline testing was completed all animals received an acute ethanol challenge while blood ethanol levels (BECs were monitored in a subset of animals. CIE exposure during adolescence, but not adulthood decreased the amount of time that animals spent in the open portions of the RAM arms (reminiscent of deficits in risk-reward integration and rendered animals more susceptible to the acute effects of an ethanol challenge on working memory tasks. The operant food reinforced task showed that these effects were not due to altered food motivation or to differential sensitivity to the nonspecific performance-disrupting effects of ethanol. However, CIE pre-treated animals had lower BEC levels than controls during the acute ethanol challenges indicating persistent pharmacokinetic tolerance to ethanol after the CIE treatment. There was little evidence of enduring effects of CIE alone on traditional measures of spatial and working memory.These effects indicate that adolescence is a time of selective vulnerability to the long-term effects of repeated ethanol exposure on neurobehavioral function and acute ethanol sensitivity. The positive and negative findings reported here help to further define the nature and extent of the impairments observed after adolescent CIE and provide direction for future

Influence of magnetic field on zebrafish activity and orientation in a plus maze.

Science.gov (United States)

Osipova, Elena A; Pavlova, Vera V; Nepomnyashchikh, Valentin A; Krylov, Viacheslav V

2016-01-01

We describe an impact of the geomagnetic field (GMF) and its modification on zebrafish's orientation and locomotor activity in a plus maze with four arms oriented to the north, east, south and west. Zebrafish's directional preferences were bimodal in GMF: they visited two arms oriented in opposed directions (east-west) most frequently. This bimodal preference remained stable for same individuals across experiments divided by several days. When the horizontal GMF component was turned 90° clockwise, the preference accordingly shifted by 90° to arms oriented to the north and south. Other modifications of GMF (reversal of both vertical and horizontal GMF components; reversal of vertical component only; and reversal of horizontal component only) did not exert any discernible effect on the orientation of zebrafish. The 90° turn of horizontal component also resulted in a significant increase of fish's locomotor activity in comparison with the natural GMF. This increase became even more pronounced when the horizontal component was repeatedly turned by 90° and back with 1min interval between turns. Our results show that GMF and its variations should be taken into account when interpreting zebrafish's directional preferences and locomotor activity in mazes and other experimental devices. Copyright © 2015. Published by Elsevier B.V.

Assessment of anxiety in open field and elevated plus maze using infrared thermography.

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Lecorps, Benjamin; Rödel, Heiko G; Féron, Christophe

2016-04-01

Due to their direct inaccessibility, affective states are classically assessed by gathering concomitant physiological and behavioral measures. Although such a dual approach to assess emotional states is frequently used in different species including humans, the invasiveness of procedures for physiological recordings particularly in smaller-sized animals strongly restricts their application. We used infrared thermography, a non-invasive method, to assess physiological arousal during open field and elevated plus maze tests in mice. By measuring changes in surface temperature indicative of the animals' emotional response, we aimed to improve the inherently limited and still controversial information provided by behavioral parameters commonly used in these tests. Our results showed significant and consistent thermal responses during both tests, in accordance with classical physiological responses occurring in stressful situations. Besides, we found correlations between these thermal responses and the occurrence of anxiety-related behaviors. Furthermore, initial temperatures measured at the start of each procedure (open field, elevated plus maze), which can be interpreted as a measure of the animals' initial physiological arousal, predicted the levels of activity and of anxiety-related behaviors displayed during the tests. Our results stress the strong link between physiological correlates of emotions and behaviors expressed during unconditioned fear tests. Copyright © 2016 Elsevier Inc. All rights reserved.

A support system for water system isolation task of nuclear power plant by using augmented reality and RFID

International Nuclear Information System (INIS)

Shimoda, Hiroshi; Ishii, Hirotake; Yamazaki, Yuichiro; Yoshikawa, Hidekazu

2004-01-01

Aiming at improvement of task performance and reduction of human error of water system isolation task in NPP periodic maintenance, a support system using state-of-art information technology. Augmented Reality (AR) and Radio Frequency Identification (RFID) has been proposed under the concept of off-site operation and maintenance support center, and a prototype system has been developed. The system has navigation function of which an indication is superimposed directly on the user's view to help to find the designated valves by AR. It also has valve confirmation function by scanning RFID tag attached on the valve. Using the prototype system, an evaluation experiment has been conducted in order to confirm its effectiveness and to reveal its problems. As the result of the experiment, it was found that the system improved efficiency and reliability of water system isolation task, and it was also found that the visibility of HMD and its troublesome feeling to wear were the problems of the system. (author)

A support system for water system isolation task of nuclear power plant by using augmented reality and RFID

Energy Technology Data Exchange (ETDEWEB)

Shimoda, Hiroshi; Ishii, Hirotake; Yamazaki, Yuichiro; Yoshikawa, Hidekazu [Kyoto Univ., Graduate School of Energy Science, Uji, Kyoto (Japan)

2004-07-15

Aiming at improvement of task performance and reduction of human error of water system isolation task in NPP periodic maintenance, a support system using state-of-art information technology. Augmented Reality (AR) and Radio Frequency Identification (RFID) has been proposed under the concept of off-site operation and maintenance support center, and a prototype system has been developed. The system has navigation function of which an indication is superimposed directly on the user's view to help to find the designated valves by AR. It also has valve confirmation function by scanning RFID tag attached on the valve. Using the prototype system, an evaluation experiment has been conducted in order to confirm its effectiveness and to reveal its problems. As the result of the experiment, it was found that the system improved efficiency and reliability of water system isolation task, and it was also found that the visibility of HMD and its troublesome feeling to wear were the problems of the system. (author)

Relations between open-field, elevated plus-maze, and emergence tests in C57BL/6J and BALB/c mice injected with GABA- and 5HT-anxiolytic agents.

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Lalonde, Robert; Strazielle, Catherine

2010-06-01

Two 5HT(1A) receptor agonists and chlordiazepoxide were examined in open-field, elevated plus maze, and emergence tests. At doses with no effect in the open-field, chlordiazepoxide increased open and open/total arm visits as well as open arm duration in the elevated plus maze, whereas 5HT(1A) receptor agonists showed an anxiolytic response on a single measure. The anxiolytic action of chlordiazepoxide was limited to the less active BALB/c strain. Unlike the 5HT(1A) receptor agonists, chlordiazepoxide was also anxiolytic in the emergence test, once again only in BALB/c and not C57BL/6J mice. Significant correlations were found between emergence latencies and specific indicators of anxiety in the elevated plus-maze in chlordiazepoxide-treated but not in mice treated with buspirone and 8-OH-DPAT. These results indicate that elevated plus-maze and emergence tests depend on benzodiazepine receptors. In contrast, 5HT(1A) receptor agonists were ineffective in the emergence test and no correlation was found between emergence latencies and specific indicators of anxiety in the elevated plus-maze. Though superficially similar, the emergence test seems to tap into a partially separate facet of anxiety.

Use of the Open Field Maze to measure locomotor and anxiety-like behavior in mice.

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Seibenhener, Michael L; Wooten, Michael C

2015-02-06

Animal models have proven to be invaluable to researchers trying to answer questions regarding the mechanisms of behavior. The Open Field Maze is one of the most commonly used platforms to measure behaviors in animal models. It is a fast and relatively easy test that provides a variety of behavioral information ranging from general ambulatory ability to data regarding the emotionality of the subject animal. As it relates to rodent models, the procedure allows the study of different strains of mice or rats both laboratory bred and wild-captured. The technique also readily lends itself to the investigation of different pharmacological compounds for anxiolytic or anxiogenic effects. Here, a protocol for use of the open field maze to describe mouse behaviors is detailed and a simple analysis of general locomotor ability and anxiety-related emotional behaviors between two strains of C57BL/6 mice is performed. Briefly, using the described protocol we show Wild Type mice exhibited significantly less anxiety related behaviors than did age-matched Knock Out mice while both strains exhibited similar ambulatory ability.

Rats prefer mutual rewards in a prosocial choice task.

Science.gov (United States)

Hernandez-Lallement, Julen; van Wingerden, Marijn; Marx, Christine; Srejic, Milan; Kalenscher, Tobias

2014-01-01

Pro-sociality, i.e., the preference for outcomes that produce benefits for other individuals, is ubiquitous in humans. Recently, cross-species comparisons of social behavior have offered important new insights into the evolution of pro-sociality. Here, we present a rodent analog of the Pro-social Choice Task that controls strategic components, de-confounds other-regarding choice motives from the animals' natural tendencies to maximize own food access and directly tests the effect of social context on choice allocation. We trained pairs of rats-an actor and a partner rat-in a double T-maze task where actors decided between two alternatives only differing in the reward delivered to the partner. The "own reward" choice yielded a reward only accessible to the actor whereas the "both reward" choice produced an additional reward for a partner (partner condition) or an inanimate toy (toy Condition), located in an adjacent compartment. We found that actors chose "both reward" at levels above chance and more often in the partner than in the toy condition. Moreover, we show that this choice pattern adapts to the current social context and that the observed behavior is stable over time.

Influence of lactation on motor activity and elevated plus maze behavior

Directory of Open Access Journals (Sweden)

Silva M.R.P.

1997-01-01

Full Text Available Lactating rats show less noise-induced freezing and fewer inhibitory responses on the 6th day post-delivery when submitted to water and food deprivation in a classical conflict paradigm. Lactating mice go more often to the illuminated chamber in a light-dark cage and stay longer in it than virgin females. The present study was designed to assess the influence of this physiological state, i.e. lactation, on the elevated plus maze (EPM and open-field behavior in adult female rats. Total (TL and central (CL locomotion and rearing (RF frequencies were measured in an open-field. Number of entries into the open and closed arms as well as the time spent in each of these arms were measured in the EPM. Percent time spent and number of entries into the open arms were calculated and compared. In the open-field, TL was significantly decreased (115 ± 10.6 vs 150 ± 11.6 while CL and RF did not differ from those presented by virgin rats. In the EPM, lactating rats displayed a significant reduction in percent time spent (10.9 ± 1.5 vs 17.4 ± 2.3 in the open arms as well as a tendency to a reduction in percent entries into the open arms (35.7 ± 4.7 vs 45.7 ± 4.3. These results show that the physiological state of lactation modulates the open-field and EPM behaviors in rats

Disruption of hippocampus-regulated behavioural and cognitive processes by heterozygous constitutive deletion of SynGAP.

Science.gov (United States)

Muhia, Mary; Yee, Benjamin K; Feldon, Joram; Markopoulos, Foivos; Knuesel, Irene

2010-02-01

The brain-specific Ras/Rap-GTPase activating protein (SynGAP) is a prime candidate linking N-methyl-d-aspartate receptors to the regulation of the ERK/MAP kinase signalling cascade, suggested to be essential for experience-dependent synaptic plasticity. Here, we evaluated the behavioural phenotype of SynGAP heterozygous knockout mice (SG(+/-)), expressing roughly half the normal levels of SynGAP. In the cognitive domain, SG(+/-) mice demonstrated severe working and reference memory deficits in the radial arm maze task, a mild impairment early in the transfer test of the water maze task, and a deficiency in spontaneous alternation in an elevated T-maze. In the non-cognitive domain, SG(+/-) mice were hyperactive in the open field and appeared less anxious in the elevated plus maze test. In contrast, object recognition memory performance was not impaired in SG(+/-) mice. The reduction in SynGAP thus resulted in multiple behavioural traits suggestive of aberrant cognitive and non-cognitive processes normally mediated by the hippocampus. Immunohistochemical evaluation further revealed a significant reduction in calbindin-positive interneurons in the hippocampus and doublecortin-positive neurons in the dentate gyrus of adult SG(+/-) mice. Heterozygous constitutive deletion of SynGAP is therefore associated with notable behavioural as well as morphological phenotypes indicative of hippocampal dysfunction. Any suggestion of a possible causal link between them however remains a matter for further investigation.

Effects of the aqueous extract of Pimpinella anisum L. seeds on exploratory activity and emotional behavior in rats using the open field and elevated plus maze tests.

Science.gov (United States)

Gamberini, Maria Thereza; Rodrigues, Domingos Sávio; Rodrigues, Daniela; Pontes, Victoria Bottino

2015-06-20

Pimpinella anisum L. is considered one of the first plants used for medicinal purposes. Pharmacological actions of the plant on the central nervous system have been proven but previous analyses have focused on anticonvulsant and neuroprotective actions. In traditional medicine worldwide, the use of Pimpinella is commonly recommended as a tranquilizer, although no scientific information supporting this use is available. Therefore, it was decided to investigate the central actions of the plant to observe behavioral responses, with an emphasis on the emotional component. To investigate the effects of the aqueous extract of Pimpinella seeds on exploratory activity and emotional behavior in rats using the open field and elevated plus maze tests. Seeds of Pimpinella were extracted with distilled water, concentrated and freeze-dried yielding the aqueous extract(AE). Rats were divided into four groups: control(water 5 mL/kg, p.o.) and AE 0.5, 1.0 and 2.0 g/kg, p.o. Individual observations were performed in an open field and the parameters locomotor activity, rearing, grooming and defecation were recorded. In elevated plus maze test, rats were divided into four groups: control(water 5 mL/kg, p.o.) and AE 0.5, 1.0 and 2.0 g/kg, p.o. The parameters arm entries, total time spent in open and closed arms; and total number of arrivals at the end of an open or closed arm were recorded for each rat. Among the parameters assessed with the open field test, only rearing was reduced in the AE 0.5 g/kg group. When AE 1.0 g/kg was administered, only the initiation of exploratory activity was delayed, without impairing the animals' general activity. The highest dose of AE (2.0 g/kg) induced a reduction in the animals' habituation during the open field test within the same session, as evidenced by the maintenance of high levels of peripheral locomotion and rearing throughout the test. On the elevated plus maze test, no alterations were observed in the responses of the animals relative to

The effects of A single dose of gamma-rays applied on the head on behavior of rats in Morris's water maze and in the open field test

International Nuclear Information System (INIS)

Smajda, B.; Kiskova, J.; Lievajova, K.; Capicikova, M.

2006-01-01

The effects of a sublethal dose of gamma-rays applied on the head on selected behavioral parameters were investigated in this study. Adult male Sprague-Dowley rats (n=9) were irradiated with a single dose of 20 Gy of gamma-rays from a 60 Co radiation source. The irradiated animals as well as sham-irradiated controls were tested daily in Morris water maze (MWM) (2 sessions per day) and in the open field test. The ability of spatial learning given by latency time to find the hidden platform was followed in MWM. The horizontal and vertical locomotion, the number of crossings of the center of the field and the washing behavior were recorded during an 8-minute test in the open field. The results obtained show, that radiation didn't altered significantly the dynamic of learning in MWM during the experiment. The level of horizontal and vertical locomotory activity in open field was lower in irradiated group in comparison with controls. The number of the crossings of the field's center, related to the level of anxiozity of animals was non-significantly lower in irradiated animals, whereas no differences in number of washing between both groups were detected. The results point to differences in radiosensitivity in various behavioral parameters in rats, maybe due to different level of their control and coordination in CNS. (authors)

Can Passive Touch Be Better than Active Touch? A Comparison of Active and Passive Tactile Maze Learning.

Science.gov (United States)

Richardson, Barry L.; And Others

1981-01-01

In a comparison of the performance of active and passive mechanically yoked subjects who learned their way through a tactile maze, it was shown that active subjects made more errors and took a greater number of trials to reach criterion than did passive subjects. (Author)

Cognitive dysfunction and histological findings in adult rats one year after whole brain irradiation

International Nuclear Information System (INIS)

Akiyama, Katsuhiko; Tanaka, Ryuichi; Sato, Mitsuya; Takeda, Norio

2001-01-01

Cognitive dysfunction and histological changes in the brain were investigated following irradiation in 20 Fischer 344 rats aged 6 months treated with whole brain irradiation (WBR) (25 Gy/single dose), and compared with the same number of sham-irradiated rats as controls. Performance of the Morris water maze task and the passive avoidance task were examined one year after WBR. Finally, histological and immunohistochemical examinations using antibodies to myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), and neurofilament (NF) were performed of the rat brains. The irradiated rats continued to gain weight 7 months after WBR whereas the control rats stopped gaining weight. Cognitive functions in both the water maze task and the passive avoidance task were lower in the irradiated rats than in the control rats. Brain damage consisting of demyelination only or with necrosis was found mainly in the body of the corpus callosum and the parietal white matter near the corpus callosum in the irradiated rats. Immunohistochemical examination of the brains without necrosis found MBP-positive fibers were markedly decreased in the affected areas by irradiation; NF-positive fibers were moderately decreased and irregularly dispersed in various shapes in the affected areas; and GFAP-positive fibers were increased, with gliosis in those areas. These findings are similar to those in clinically accelerated brain aging in conditions such as Alzheimer's disease, Binswanger's disease, and multiple sclerosis. (author)

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.

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

Science.gov (United States)

Sebastian, Veronica; Diallo, Aissatou; Ling, Douglas S F; Serrano, Peter A

2013-01-01

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 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 four baited and four unbaited arms. Subjects were given 10 daily trials for 6 days followed by a memory retrieval test 2 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 2 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.

Rats prefer mutual rewards in a ProSocial Choice Task

Directory of Open Access Journals (Sweden)

Julen eHernandez-Lallement

2015-01-01

Full Text Available Pro-sociality, i.e. the preference for outcomes that produce benefits for other individuals, is ubiquitous in humans. Recently, cross-species comparisons of social behavior have offered important new insights into the evolution of pro-sociality. Here, we present a rodent analog of the Pro-social Choice Task that controls strategic components, de-confounds other-regarding choice motives from the animals’ natural tendencies to maximize own food access and directly tests the effect of social context on choice allocation. We trained pairs of rats – an actor and a partner rat – in a double T-maze task where actors decided between two alternatives only differing in the reward delivered to the partner. The own reward choice yielded a reward only accessible to the actor whereas the both reward choice produced an additional reward for a partner (partner condition or an inanimate toy (toy Condition, located in an adjacent compartment. We found that actors chose both reward at levels above chance and more often in the partner than in the toy condition. Moreover, we show that this choice pattern adapts to the current social context and that the observed behavior is stable over time.

A Virtual Reality Task Based on Animal Research - Spatial Learning and Memory in Patients after the First Episode of Schizophrenia

Directory of Open Access Journals (Sweden)

Iveta eFajnerova

2014-05-01

Full Text Available Objective: Cognitive deficit is considered to be a characteristic feature of schizophrenia disorder. A similar cognitive dysfunction was demonstrated in animal models of schizophrenia. However, the poor comparability of methods used to assess cognition in animals and humans could be responsible for low predictive validity of current animal models. In order to assess spatial abilities in schizophrenia and compare our results with the data obtained in animal models we designed a virtual analogue of the Morris water maze (MWM, the virtual Four Goals Navigation (vFGN task.Method: Twenty-nine patients after the first psychotic episode with schizophrenia symptoms and a matched group of healthy volunteers performed the vFGN task. They were required to find and remember four hidden goal positions in an enclosed virtual arena. The task consisted of two parts. The Reference memory (RM session with a stable goal position was designed to test spatial learning. The Delayed-matching-to-place (DMP session presented a modified working memory protocol designed to test the ability to remember a sequence of three hidden goal positions.Results: Data obtained in the RM session show impaired spatial learning in schizophrenia patients compared to healthy controls in pointing and navigation accuracy. The DMP session showed impaired spatial memory in schizophrenia during the recall of spatial sequence and similar deficit in spatial bias in probe trials. The pointing accuracy and the quadrant preference showed higher sensitivity toward the cognitive deficit than the navigation accuracy. Direct navigation to the goal was affected by sex and age of the tested subjects. Age affected spatial performance only in healthy controls. Conclusions: Despite some limitations of the study, our results correspond well to previous studies in animal models of schizophrenia and support the decline of spatial cognition in schizophrenia, indicating the usefulness of the vFGN task in

Improvement of Radiation Safety in Radiotherapy Facilities: Catering for Neutrons Outside Short Mazes in 10MV Linear Accelerators

International Nuclear Information System (INIS)

Severa, R.

2016-01-01

It has been demonstrated that neutron leakage cannot be neglected at 10MV when direct access doors are used or when short mazes, typically less than 7 metres in length, are employed. The majority of radiotherapy facilities in Africa have Co-60 machines installed that are now being replaced by linear accelerators. The in-coming linear accelerators are being installed in the same bunkers that were designed for Co-60 energy ranges albeit with some shielding modifications. The modifications do not alter the length of the maze and where the maze length is less than 7 metres, neutron leakage will occur in 10MV linear accelerators. There is lack of capacity within the regulatory bodies in Africa to handle this changeover from a technical and equipment perspective. The justification of medical exposures ensures that the benefits to the patients substantially outweigh any risks that the patient may incur. As such, the justification process needs to be implemented through the effective use of evidence-based referral guidelines and clinical audits. In the case of most African countries, medical diagnostic exposures of patients are not underpinned by an effective justification system. This, coupled with the scenario where physicians own outpatient diagnostic centres to which they refer patients (self-referral) increases the conflict of physicians due to dual roles as professionals and businessmen, further compromising on patient protection. Nuclear security is the responsibility of the Member State and requires that a number of key stakeholders work closely together. In the case of research reactors and nuclear power plants, this cooperation is evident and functional. However, this does not extend to the use of high-activity radioactive sources in medicine (category 1&2) where in most cases the regulators seem to be the only authority having oversight on the security of these sources without the benefit of direct input and collaboration of other key security stakeholders. This

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

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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…

Potentiation and Overshadowing of Shape by Wall Color in a Kite-Shaped Maze Using Rats in a Foraging Task

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Cole, Mark R.; Gibson, Laura; Pollack, Adam; Yates, Lynsey

2011-01-01

The interaction between redundant geometric and featural cues in open field search tasks has been examined widely with results that are not always consistent. Cheng (1986) found evidence that when searching for food in rectangular environments, rats used the geometrical characteristics of the environment rather than local featural cues, suggesting…

Models of anxiety: responses of mice to novelty and open spaces in a 3D maze.

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

2006-11-01

The present report describes the emotional responses of different strains of mice to exposure to a novel open space model of anxiety using a 3D spatial navigation task. The 3D maze is modification of the radial maze with flexible arms that can be raised above or lowered below the horizontal level of a central platform. To access the arms animals need to cross a bridge linking the arms to the central platform. In this model, mice are exposed to novelty in an unfamiliar open space setting with no safe alternative. Fear from novelty is compounded with the need to explore. The drive to escape and the drive to approach are intermingled making this open space model radically different from the current models of anxiety which provide animals with the choice between safe and anxiogenic spaces. In a series of experiments, we examined the behaviour of different groups of mice from C57, C3H, CD1 and Balb/c strains. In the first experiment, different groups of C57 mice were tested in one of the three arms configurations. In the second experiment, C57 mice were compared to C3H mice. In the third experiment, C57 mice were compared to CD1 and Balb/c mice in the raised arm configuration over three successive sessions. In the fourth experiment, we examined the behaviour of C57 mice in the lowered arm configuration with an open and an enclosed central. In the final experiment, we examined the difference between C57 and C3H mice of both genders. Using several spatio-temporal parameters of the transition responses between central platform, bridges and arms, we have been able to show consistent results demonstrating significant differences between C57 and C3H mice, and between Balb/c and both C57 and CD1 mice. C3H appear more anxious than C57 mice, and Balb/c mice seem more anxious than C57 and CD1 mice. We also observed significant differences between sexes in C3H mice but not in C57 mice. C3H male mice appear more anxious than C3H female mice and than both C57 male and female mice

Effects of treadmill exercise intensity on spatial working memory and long-term memory in rats.

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Wang, Xiao-Qin; Wang, Gong-Wu

2016-03-15

Moderate exercise promotes learning and memory. Most studies mainly focused on memory exercise effects of in the ageing and patients. There is lack of quantitative research about effect of regular exercise intensity on different memory types in normal subjects. Present study investigated the effects of different intensities of treadmill exercise on working memory and long-term memory. Fifty female Wistar rats were trained by T-maze delayed spatial alternation (DSA) task with 3 delays (10s, 60s and 300s). Then they got a 30min treadmill exercise for 30days in 4 intensities (control, 0m/min; lower, 15m/min; middle, 20m/min, and higher, 30m/min). Then animals were tested in DSA, passive avoidance and Morris water maze tasks. 1. Exercise increased the neuronal density of hippocampal subregions (CA1, CA3 and dentate gyrus) vs. naïve/control. 2. In DSA task, all groups have similar baseline, lower intensity improved 10s delay accuracy vs. baseline/control; middle and higher intensities improved 300s delay accuracy vs. baseline/control. 3. In water maze learning, all groups successfully found the platform, but middle intensity improved platform field crossing times vs. control in test phase. Present results suggested that treadmill exercise can improve long-term spatial memory and working memory; lower intensity benefits to short-term delayed working memory, and middle or higher intensity benefits to long-term delayed working memory. There was an inverted U dose-effect relationship between exercise intensity and memory performance, but exercise -working memory effect was impacted by delay duration. Copyright © 2016 Elsevier Inc. All rights reserved.

Endogenous IL-1 in cognitive function and anxiety: a study in IL-1RI-/- mice.

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Carol L Murray

Full Text Available Interleukin-1 (IL-1 is a key pro-inflammatory cytokine, produced predominantly by peripheral immune cells but also by glia and some neuronal populations within the brain. Its signalling is mediated via the binding of IL-1α or IL-1β to the interleukin-1 type one receptor (IL-1RI. IL-1 plays a key role in inflammation-induced sickness behaviour, resulting in depressed locomotor activity, decreased exploration, reduced food and water intake and acute cognitive deficits. Conversely, IL-1 has also been suggested to facilitate hippocampal-dependent learning and memory: IL-1RI(-/- mice have been reported to show deficits on tasks of visuospatial learning and memory. We sought to investigate whether there is a generalised hippocampal deficit in IL-1RI(-/- animals. Therefore, in the current study we compared wildtype (WT mice to IL-1RI(-/- mice using a variety of hippocampal-dependent learning and memory tasks, as well as tests of anxiety and locomotor activity. We found no difference in performance of the IL-1RI(-/- mice compared to WT mice in a T-maze working memory task. In addition, the IL-1RI(-/- mice showed normal learning in various spatial reference memory tasks including the Y-maze and Morris mater maze, although there was a subtle deficit in choice behaviour in a spatial discrimination, beacon watermaze task. IL-1RI(-/- mice also showed normal memory for visuospatial context in the contextual fear conditioning paradigm. In the open field, IL-1RI(-/- mice showed a significant increase in distance travelled and rearing behaviour compared to the WT mice and in the elevated plus-maze spent more time in the open arms than did the WT animals. The data suggest that, contrary to prior studies, IL-1RI(-/- mice are not robustly impaired on hippocampal-dependent memory and learning but do display open field hyperactivity and decreased anxiety compared to WT mice. The results argue for a careful evaluation of the roles of endogenous IL-1 in hippocampal

Long-Term Effects of Chronic Intermittent Ethanol Exposure in Adolescent and Adult Rats: Radial-Arm Maze Performance and Operant Food Reinforced Responding

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Risher, Mary-Louise; Fleming, Rebekah L.; Boutros, Nathalie; Semenova, Svetlana; Wilson, Wilkie A.; Levin, Edward D.; Markou, Athina; Swartzwelder, H. Scott; Acheson, Shawn K.

2013-01-01

Background Adolescence is not only a critical period of late-stage neurological development in humans, but is also a period in which ethanol consumption is often at its highest. Given the prevalence of ethanol use during this vulnerable developmental period we assessed the long-term effects of chronic intermittent ethanol (CIE) exposure during adolescence, compared to adulthood, on performance in the radial-arm maze (RAM) and operant food-reinforced responding in male rats. Methodology/Principal Findings Male Sprague Dawley rats were exposed to CIE (or saline) and then allowed to recover. Animals were then trained in either the RAM task or an operant task using fixed- and progressive- ratio schedules. After baseline testing was completed all animals received an acute ethanol challenge while blood ethanol levels (BECs) were monitored in a subset of animals. CIE exposure during adolescence, but not adulthood decreased the amount of time that animals spent in the open portions of the RAM arms (reminiscent of deficits in risk-reward integration) and rendered animals more susceptible to the acute effects of an ethanol challenge on working memory tasks. The operant food reinforced task showed that these effects were not due to altered food motivation or to differential sensitivity to the nonspecific performance-disrupting effects of ethanol. However, CIE pre-treated animals had lower BEC levels than controls during the acute ethanol challenges indicating persistent pharmacokinetic tolerance to ethanol after the CIE treatment. There was little evidence of enduring effects of CIE alone on traditional measures of spatial and working memory. Conclusions/Significance These effects indicate that adolescence is a time of selective vulnerability to the long-term effects of repeated ethanol exposure on neurobehavioral function and acute ethanol sensitivity. The positive and negative findings reported here help to further define the nature and extent of the impairments observed

Water management. A core task of the Wismut remediation programme; Kernaufgaben des langfristigen Wassermanagements an den saechsisch-thueringischen Wismut-Standorten

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Paul, Michael; Meyer, Juergen; Jenk, Ulf; Kassahun, Andrea; Schramm, Andrea; Baacke, Delf; Forbrig, Norbert; Metschies, Thomas [Wismut GmbH, Chemnitz (Germany). Bereich Ingenieurwesen/Strahlenschutz

2015-07-01

Water management and conventional technical water treatment are by far the most cost-intensive long-term tasks of the Wismut remediation programme. Over the medium term, there is no viable alternative to the operation of active systems to catch and treat contaminated mine waters at the Ronneburg, Schlema, Koenigstein, Poehla, Seelingstaedt and Heimsdorf sites. Based on the status quo this paper outlines the key issues of the Wismut GmbH water management strategy over the medium and long term. lt is focused primarily on achieving protection goals for potentially impacted water bodies in the surroundings of Wismut sites and on optimising associated remediation expenditure as well as on creating the prerequisites for achieving low post-remedial care and maintenance or walk-away system status over the long term. The topic of this paper is the presentation of priority tasks related to future water management at Wismut sites in Saxony and Thuringia. The reflections are based on experiences and lessons learned and take into account current statutory management requirements referring to ground and surface water bodies affected by Wismut. The paper is based on a presentation made at the International Mining Symposium WISSYM 2015 on 2nd September 2015 in Bad Schlema, Germany.

Pre-Exposure to Context Affects Learning Strategy Selection in Mice

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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)…

The effects of response cost and species-typical behaviors on a daily time-place learning task.

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Deibel, Scott H; Thorpe, Christina M

2013-03-01

Two theories that have been hypothesized to mediate acquisition in daily time-place learning (TPL) tasks were investigated in a free operant daily TPL task: the response cost hypothesis and the species-typical behavior hypothesis. One lever at the end of one of the choice arms of a T-maze provided food in the morning, and 6 h later, a lever in the other choice arm provided food. Four groups were used to assess the effect of two possible sources of response cost: physical effort of the task and costs associated with foraging ecology. One group was used to assess the effect of explicitly allowing for species-typical behaviors. If only first arm choice data were considered, there was little evidence of learning. However, both first press and percentage of presses on the correct lever prior to the first reinforcement revealed evidence of TPL in most rats tested. Unexpectedly, the high response cost groups for both of the proposed sources did not perform better than the low response cost groups. The groups that allowed animals to display species-typical behaviors performed the worst. Skip session probe trials confirmed that the majority of the rats that acquired the task were using a circadian timing strategy. The results from the present study suggest that learning in free operant daily TPL tasks might not be dependent on response cost.

Effects of early maternal separation on the performance in the elevated plus maze in adult rats

International Nuclear Information System (INIS)

Leon Rodriguez, Diego Armando; Duenas Gomez, Zulma Janeth

2012-01-01

It has been demonstrated that disruption of mother pup interaction during early life exerts long lasting effects on the brain and behavioral development. Therefore subjects exposed to early maternal separation stress (MS) show variations in anxiety like behaviors. The aim of this study was to investigate the specific effects of SMT stress on anxiety like behaviors in adult male and female wistar rats. Rats were housed with reversed light dark cycle (light on at 7 p.m., off at 7 a.m.), water and food ad libitum. Separation was carried out in postnatal days 1 to 21, twice daily in dark cycle (7:00 a 10:00 y 13:00 a 16:00 p.m.). The anxiety like behaviors were tested through the elevated plus maze (EPM) when the pups reached 230 g of weigh. We found that the MS stress has sex specific effects on anxiety like behaviors: the maternal separated females displayed a lesser anxious outline than the not separated ones and the separated males showed a large exploration/avoidance conflict. These results confirm previous effects of our labs, which may be related to an interaction between vulnerability to environmental challenge and maternal care compensatory behaviors

Phobos: A novel software for recording rodents' behavior during the thigmotaxis and the elevated plus-maze test.

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Telonis, Aristeidis G; Margarity, Marigoula

2015-07-10

Evaluation of fear and anxiety levels offers valuable insight on the impact of experimental conditions. The elevated plus-maze and the open field (thigmotactic responce) tests are two well-established behavioral procedures for the quantification of anxiety in rodents. In this study, Phobos, a novel, effective and simple application developed for recording rodents' behavior during the elevated plus-maze and the open-field test, is being presented. Phobos is able to generate all basic locomotor-related behavioral results at once, immediately after a simple manual record of the rodent's position, along with simultaneous analysis of the experiment in 5-min periods. The efficiency of Phobos is demonstrated by presenting results from the two behavioral tests showing that animal's behavior unfolds differently in each one. Phobos manages to ease the experimenter from laborious work by providing self-explanatory characteristics and a convenient way to record the behavior of the animal, while it quickly calculates all basic locomotor-related parameters, easing behavioral studies. Phobos is freely accessible at https://sourceforge.net/projects/phobosapplication/. Copyright © 2015. Published by Elsevier Ireland Ltd.

Leptin attenuates the detrimental effects of β-amyloid on spatial memory and hippocampal later-phase long term potentiation in rats.

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Tong, Jia-Qing; Zhang, Jun; Hao, Ming; Yang, Ju; Han, Yu-Fei; Liu, Xiao-Jie; Shi, Hui; Wu, Mei-Na; Liu, Qing-Song; Qi, Jin-Shun

2015-07-01

β-Amyloid (Aβ) is the main component of amyloid plaques developed in the brain of patients with Alzheimer's disease (AD). The increasing burden of Aβ in the cortex and hippocampus is closely correlated with memory loss and cognition deficits in AD. Recently, leptin, a 16kD peptide derived mainly from white adipocyte tissue, has been appreciated for its neuroprotective function, although less is known about the effects of leptin on spatial memory and synaptic plasticity. The present study investigated the neuroprotective effects of leptin against Aβ-induced deficits in spatial memory and in vivo hippocampal late-phase long-term potentiation (L-LTP) in rats. Y maze spontaneous alternation was used to assess short term working memory, and the Morris water maze task was used to assess long term reference memory. Hippocampal field potential recordings were performed to observe changes in L-LTP. We found that chronically intracerebroventricular injection of leptin (1μg) effectively alleviated Aβ1-42 (20μg)-induced spatial memory impairments of Y maze spontaneous alternation and Morris water maze. In addition, chronic administration of leptin also reversed Aβ1-42-induced suppression of in vivo hippocampal L-LTP in rats. Together, these results suggest that chronic leptin treatments reversed Aβ-induced deficits in learning and memory and the maintenance of L-LTP. Copyright © 2015 Elsevier Inc. All rights reserved.

Time flies faster under time pressure.

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Rattat, Anne-Claire; Matha, Pauline; Cegarra, Julien

2018-04-01

We examined the effects of time pressure on duration estimation in a verbal estimation task and a production task. In both temporal tasks, participants had to solve mazes in two conditions of time pressure (with or without), and with three different target durations (30 s, 60 s, and 90 s). In each trial of the verbal estimation task, participants had to estimate in conventional time units (minutes and seconds) the amount of time that had elapsed since they started to solve the maze. In the production task, they had to press a key while solving the maze when they thought that the trial's duration had reached a target value. Results showed that in both tasks, durations were judged longer with time pressure than without it. However, this temporal overestimation under time pressure did not increase with the length of the target duration. These results are discussed within the framework of scalar expectancy theory. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of periadolescent fluoxetine and paroxetine on elevated plus-maze, acoustic startle, and swimming immobility in rats while on and off-drug.

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Vorhees, Charles V; Morford, LaRonda R; Graham, Devon L; Skelton, Matthew R; Williams, Michael T

2011-10-05

Whether selective serotonin reuptake inhibitors (SSRIs) exposure during adolescent brain development causes lasting effects remains unresolved. Assess the effects of fluoxetine and paroxetine 60 days after adolescent exposure compared with when on-drug. 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). 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 (pfluoxetine and paroxetine (N=20-21/group). No differences on immobility time were seen in the Porsolt forced swim test or in plasma corticosterone at the end of forced swim (N-19-21/group). Off-drug, no effects were seen in the elevated plus maze (N=16/group), ASR/PPI (N=20/group), forced swim (N=19-20/group), or plasma corticosterone (N=19/group). At the doses tested, fluoxetine and paroxetine induced minor effects with drug on-board but no residual, long-term adverse effects in rats 60 days after drug discontinuation. 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.

Training on motor and visual spatial learning tasks in early adulthood produces large changes in dendritic organization of prefrontal cortex and nucleus accumbens in rats given nicotine prenatally.

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Muhammad, A; Mychasiuk, R; Hosain, S; Nakahashi, A; Carroll, C; Gibb, R; Kolb, B

2013-11-12

Experience-dependent plasticity is an ongoing process that can be observed and measured at multiple levels. The first goal of this study was to examine the effects of prenatal nicotine on the performance of rats in three behavioral tasks (elevated plus maze (EPM), Morris water task (MWT), and Whishaw tray reaching). The second goal of this experiment sought to examine changes in dendritic organization following exposure to the behavioral training paradigm and/or low doses of prenatal nicotine. Female Long-Evans rats were administered daily injections of nicotine for the duration of pregnancy and their pups underwent a regimen of behavioral training in early adulthood (EPM, MWT, and Whishaw tray reaching). All offspring exposed to nicotine prenatally exhibited substantial increases in anxiety. Male offspring also showed increased efficiency in the Whishaw tray-reaching task and performed differently than the other groups in the probe trial of the MWT. Using Golgi-Cox staining we examined the dendritic organization of the medial and orbital prefrontal cortex as well as the nucleus accumbens. Participation in the behavioral training paradigm was associated with dramatic reorganization of dendritic morphology and spine density in all brain regions examined. Although both treatments (behavior training and prenatal nicotine exposure) markedly altered dendritic organization, the effects of the behavioral experience were much larger than those of the prenatal drug exposure, and in some cases interacted with the drug effects. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Strategic neuronal encoding in medial prefrontal cortex of spatial working memory in the T-maze.

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Yang, Yang; Mailman, Richard B

2018-05-02

Strategic neuronal encoding in the medial prefrontal cortex (mPFC) of the rat was correlated with spatial working memory (sWM) assessed by behavior in the T-maze. Neurons increased their firing rate around choice, with the increase largely occurring before choice as a prospective encode of behavior. This could be classified as sensitive-to-spatial information or sensitive-to-choice outcome. The sensitivity-to-spatial choice was defined by distinct firing rate changes before left- or right-choice. The percentage of left-choice sensitive neurons was not different from the percentage of right-choice sensitive neurons. There was also location-related neuronal activity in which neurons fired at distinct rates when rats were in a left- or right-location. More neurons were sensitive to left-location, as most of them were recorded from rats preferring to enter the right-location. The sensitivity to outcome was defined by a distinct firing rate around correct or error choice. Significantly more neurons were sensitive to error outcome, and, among these, more preferred to encode prospectively, increasing firing in advance of an error outcome. Similar to single neuron activity, the mPFC enhanced its neuronal network as measured by the oscillation of local field potential. The maximum power of oscillation was around choice, and occurred slightly earlier before error versus before correct outcome. Thus, sWM modulation in the mPFC includes not only spatial, but also outcome-related inputs, and neuronal ensembles monitor behavioral outcome to make strategic adjustments ensuring successful task performance. Copyright © 2018 Elsevier B.V. All rights reserved.

Differential functions of NR2A and NR2B in short-term and long-term memory in rats.

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Jung, Ye-Ha; Suh, Yoo-Hun

2010-08-23

N-methyl-D-aspartate receptors (NMDARs) are glutamate receptors implicated in synaptic plasticity and memory function. The specific functions of NMDA receptor subunits NR2A and NR2B have not yet been fully determined in the different types of memory. Nine Wistar rats (8-weeks-old) were subjected to the Morris water maze task to evaluate the memory behaviorally. Quantitative analysis of NR1, NR2A, and NR2B levels in the right and left forebrain of rats was performed and subunit associations with different types of memory were investigated using the Morris water maze task. Right forebrain NR2A expression was significantly increased and correlated with faster escape time onto a hidden platform, indicating involvement of short-term memory, because of the training time interval. Right forebrain NR2B expression was positively associated with long-term memory lasting 24-h (h). In the left forebrain, NR2B expression was positively related to 72-h long-term memory. In conclusion, the functions of NR2A and NR2B receptors were differentially specialized in short-term and long-term memory, depending on the right or left forebrain.

An Observation Task Chain Representation Model for Disaster Process-Oriented Remote Sensing Satellite Sensor Planning: A Flood Water Monitoring Application

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Chao Yang

2018-03-01

Full Text Available An accurate and comprehensive representation of an observation task is a prerequisite in disaster monitoring to achieve reliable sensor observation planning. However, the extant disaster event or task information models do not fully satisfy the observation requirements for the accurate and efficient planning of remote-sensing satellite sensors. By considering the modeling requirements for a disaster observation task, we propose an observation task chain (OTChain representation model that includes four basic OTChain segments and eight-tuple observation task metadata description structures. A prototype system, namely OTChainManager, is implemented to provide functions for modeling, managing, querying, and visualizing observation tasks. In the case of flood water monitoring, we use a flood remote-sensing satellite sensor observation task for the experiment. The results show that the proposed OTChain representation model can be used in modeling process-owned flood disaster observation tasks. By querying and visualizing the flood observation task instances in the Jinsha River Basin, the proposed model can effectively express observation task processes, represent personalized observation constraints, and plan global remote-sensing satellite sensor observations. Compared with typical observation task information models or engines, the proposed OTChain representation model satisfies the information demands of the OTChain and its processes as well as impels the development of a long time-series sensor observation scheme.

Infection of male rats with Toxoplasma gondii induces effort-aversion in a T-maze decision-making task.

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Tan, Donna; Vyas, Ajai

2016-03-01

Rats chronically infected with protozoan Toxoplasma gondii exhibit greater delay aversion in an inter-temporal task. Moreover T. gondii infection also results in dendritic atrophy of basolateral amygdala neurons. Basolateral amygdala is reported to bias decision making towards greater effortful alternatives. In this context, we report that T. gondii increases effort aversion in infected male rats. This host-parasite association has been widely studied in the context of loss of innate fear in the infected males. It is suggested that reduced fear towards predators reflects a parasitic behavioral manipulation to enhance trophic transmission of T. gondii. Observations reported here extend this paradigm away from a monolithic change in fear and towards a multi-dimensional change in decision making. Copyright © 2016 Elsevier Inc. All rights reserved.

Female Sprague Dawley Rats Show Impaired Spatial Memory in the 8-Arm Radial Maze under Dim Blue and Red Light

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Michael Pirchl

2010-01-01

Full Text Available Light intensity and wavelength strongly influence mood and cognition in humans and rodent animal models. The aim of the present study was to explore if dim white (7.6–17.7 lux , blue (1.3–2.3 lux, and red light (0.8–1.4 lux affect spatial memory of male and female Sprague Dawley rats in the 8-arm radial maze. Our data show that spatial memory significantly improved within 5 daily learning sessions (each 5 trials under dim white light, which was not different between male and female rats. However, dim blue and red light significantly reduced spatial learning of female rats in the 8-arm radial maze in the last training session (session 5. In conclusion, we suggest that female Sprague Dawley rats show reduced learning under blue and red light.

The role of the medial caudate nucleus, but not the hippocampus, in a matching-to sample task for a motor response.

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Kesner, Raymond P; Gilbert, Paul E

2006-04-01

A delayed-match-to-sample task was used to assess memory for motor responses in rats with control, hippocampus, or medial caudate nucleus (MCN) lesions. All testing was conducted on a cheeseboard maze in complete darkness using an infrared camera. A start box was positioned in the centre of the maze facing a randomly determined direction on each trial. On the sample phase, a phosphorescent object was randomly positioned to cover a baited food well in one of five equally spaced positions around the circumference of the maze forming a 180-degree arc 60 cm from the box. The rat had to displace the object to receive food and return to the start box. The box was then rotated to face a different direction. An identical baited phosphorescent object was placed in the same position relative to the start box. A second identical object was positioned to cover a different unbaited well. On the choice phase, the rat must remember the motor response made on the sample phase and make the same motor response on the choice phase to receive a reward. Hippocampus lesioned and control rats improved as a function of increased angle separation used to separate the correct object from the foil (45, 90, 135, and 180 degrees) and matched the performance of controls. However, rats with MCN lesions were impaired across all separations. Results suggest that the MCN, but not the hippocampus, supports working memory and/or a process aimed at reducing interference for motor response selection based on vector angle information.

GABA(A) and dopamine receptors in the nucleus accumbens shell differentially influence performance of a water-reinforced progressive ratio task.

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Covelo, Ignacio R; Wirtshafter, David; Stratford, Thomas R

2012-03-01

Several authors have shown that injections of the GABA(A) agonist muscimol into the medial shell region of the nucleus accumbens (AcbSh) result in large increases in food, but not water, intake. In previous studies we demonstrated that intra-AcbSh injections of either muscimol or of the indirect dopamine agonist amphetamine increase response output on a food-reinforced progressive ratio schedule. In the current experiment we extended these observations by examining the effects of muscimol and amphetamine injections on the performance of a water-reinforced progressive ratio task in mildly deprived animals. We found that muscimol did not affect the number of responses made in the water-reinforced task, even though a marked increase in responding was observed after amphetamine. Muscimol did, however, significantly increase food intake in the same animals. The results suggest that the enhancing effects of intra-AcbSh muscimol differ from those of amphetamine in that they are selective for food-reinforced behaviors. Copyright © 2011. Published by Elsevier Inc.

Neuroprotective and Antiamnesic Effects of Mitragyna inermis Willd (Rubiaceae on Scopolamine-Induced Memory Impairment in Mice

Directory of Open Access Journals (Sweden)

David Bougolla Pahaye

2017-01-01

Full Text Available Aim. To assess memory improvement and neuroprotective and antioxidant effects of Mitragyna inermis (M. inermis leaf decoction on the central nervous system. Methodology. Leaf decoction of M. inermis was tested on learning and memory in normal and scopolamine-induced cognitive impairment in mice using memory behavioral tests such as the Morris water maze, object recognition task, and elevated plus maze. Oxidative stress enzymes—catalase, superoxide dismutase, and the thiobarbituric acid reactive substance, a product of lipid peroxidation—were quantified. In each test, mice 18 to 25 g were divided into groups of 5. Results. The extract reversed the effects of scopolamine in mice. The extract significantly increased discrimination index in the object recognition task test and inflexion ratio in the elevated plus maze test. The times spent in target quadrant in MWM increased while the transfer latency decreased in mice treated by M. inermis at the dose of 196.5 mg/kg. The activity levels of superoxide dismutase and catalase were significantly increased, whereas the thiobarbituric acid reactive substance was significantly decreased after 8 consecutive days of treatment with M. inermis at the dose of 393 mg/kg. Conclusion. These results suggest that M. inermis leaf extract possess potential antiamnesic effects.

Interactions between the toxin kid of the bacterial parD system and the antitoxins Kis and MazE

NARCIS (Netherlands)

Kamphuis, M.B.; Monti, M.C.; van den Heuvel, R.H.H.; Santos-Sierra, S.; Folkers, G.E.; Lemonnier, M.; Diaz-Orejas, R.; Heck, A.J.R.; Boelens, R.

2007-01-01

The proteins Kid and Kis are the toxin and antitoxin, respectively, encoded by the parD operon of Escherichia coli plasmid R1. Kis prevents the inhibition of E. coli cell growth caused by the RNA cleavage activity of Kid. Overproduction of MazE, the chromosome-encoded homologue of Kis, has been

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

Science.gov (United States)

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

2009-09-14

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

Engineering task plan for the development of a high pressure water drill system for BY-105 saltwell screen installation

International Nuclear Information System (INIS)

RITTER, G.A.

1999-01-01

This engineering task plan identifies the activities required for developing an ultra high pressure water drill system for installation of a saltwell screen in Tank BY-105. A water drill system is needed to bore through the hard waste material in this tank because of the addition of Portland cement in the 1960s and/or 1970s. The activities identified in this plan include the design, procurement, and qualification testing of the water drill along with readiness preparations including developing operating procedures, training Operations personnel, and conducting an assessment of readiness

A solution for two-dimensional mazes with use of chaotic dynamics in a recurrent neural network model.

Science.gov (United States)

Suemitsu, Yoshikazu; Nara, Shigetoshi

2004-09-01

Chaotic dynamics introduced into a neural network model is applied to solving two-dimensional mazes, which are ill-posed problems. A moving object moves from the position at t to t + 1 by simply defined motion function calculated from firing patterns of the neural network model at each time step t. We have embedded several prototype attractors that correspond to the simple motion of the object orienting toward several directions in two-dimensional space in our neural network model. Introducing chaotic dynamics into the network gives outputs sampled from intermediate state points between embedded attractors in a state space, and these dynamics enable the object to move in various directions. System parameter switching between a chaotic and an attractor regime in the state space of the neural network enables the object to move to a set target in a two-dimensional maze. Results of computer simulations show that the success rate for this method over 300 trials is higher than that of random walk. To investigate why the proposed method gives better performance, we calculate and discuss statistical data with respect to dynamical structure.

A statistical approach for segregating cognitive task stages from multivariate fMRI BOLD time series

Directory of Open Access Journals (Sweden)

Charmaine eDemanuele

2015-10-01

Full Text Available Multivariate pattern analysis can reveal new information from neuroimaging data to illuminate human cognition and its disturbances. Here, we develop a methodological approach, based on multivariate statistical/machine learning and time series analysis, to discern cognitive processing stages from fMRI blood oxygenation level dependent (BOLD time series. We apply this method to data recorded from a group of healthy adults whilst performing a virtual reality version of the delayed win-shift radial arm maze task. This task has been frequently used to study working memory and decision making in rodents. Using linear classifiers and multivariate test statistics in conjunction with time series bootstraps, we show that different cognitive stages of the task, as defined by the experimenter, namely, the encoding/retrieval, choice, reward and delay stages, can be statistically discriminated from the BOLD time series in brain areas relevant for decision making and working memory. Discrimination of these task stages was significantly reduced during poor behavioral performance in dorsolateral prefrontal cortex (DLPFC, but not in the primary visual cortex (V1. Experimenter-defined dissection of time series into class labels based on task structure was confirmed by an unsupervised, bottom-up approach based on Hidden Markov Models. Furthermore, we show that different groupings of recorded time points into cognitive event classes can be used to test hypotheses about the specific cognitive role of a given brain region during task execution. We found that whilst the DLPFC strongly differentiated between task stages associated with different memory loads, but not between different visual-spatial aspects, the reverse was true for V1. Our methodology illustrates how different aspects of cognitive information processing during one and the same task can be separated and attributed to specific brain regions based on information contained in multivariate patterns of voxel

A virtual reality task based on animal research – spatial learning and memory in patients after the first episode of schizophrenia

Czech Academy of Sciences Publication Activity Database

Fajnerová, Iveta; Rodriguez, M.; Levčík, David; Konrádová, L.; Mikoláš, P.; Brom, C.; Stuchlík, Aleš; Vlček, Kamil; Horáček, J.

2014-01-01

Roč. 8, May 27 (2014), s. 157 ISSN 1662-5153 R&D Projects: GA MZd(CZ) NT13386 Grant - others:GA MZd(CZ) NT14291; GA MZd(CZ) NT13843 Institutional support: RVO:67985823 Keywords : schizophrenia * spatial navigation * learning and memory * virtual reality environment * cognitive deficit * Morris Water Maze (MWM) * psychotic disorders * spatial behavior Subject RIV: FH - Neurology Impact factor: 3.270, year: 2014

A support system for water system isolation task in NPP by using augmented reality and RFID

Energy Technology Data Exchange (ETDEWEB)

Shimoda, Hiroshi; Ishii, Hirotake; Yamazaki, Yuichiro [Kyoto Univ., Uji (Japan). Graduate School of Energy Science; Wu, Wei [Mitsubishi Electric Corp., Amagasaki, Hyogo (Japan); Yoshikawa, Hidekazu [Kyoto Univ., Kyoto (Japan). Graduate School of Energy Science

2004-07-01

Aiming at improvement of task performance and reduction of human error of water system isolation task in NPP periodic maintenance, a support system using state-of-art information technology, Augmented Reality (AR) and Radio Frequency Identification (RFID) has been proposed, and a prototype system has been developed. The system has navigation function of which an indication is superimposed directly on the user's view to help to find the designated valves by AR. It also has valve confirmation function by scanning RFID tag attached on the valve. In case of applying it to practical use, its information presentation device is important because it affects the task performance. In this study, therefore, a suitable information presentation device has been pursued by conducting subject experiments employing psychological experimental technique. The candidates of the devices are one-eye video see-through HMD (SCOPO) and both-eye video see-through HMD (Glasstron) as wearable system configuration, and tablet PC and compact TV as handheld system configuration. In the experiment, task completion time, number of errors, NASA-TLX score as subjects' mental workload and subjective usability questionnaire were measured when using the above devices. As the results, it was found that one-eye video see-through head mounted display, SCOPO was suitable device as wearable system configuration, and compact TV was suitable device as handheld system configuration. (author)

A support system for water system isolation task in NPP by using augmented reality and RFID

International Nuclear Information System (INIS)

Shimoda, Hiroshi; Ishii, Hirotake; Yamazaki, Yuichiro; Yoshikawa, Hidekazu

2004-01-01

Aiming at improvement of task performance and reduction of human error of water system isolation task in NPP periodic maintenance, a support system using state-of-art information technology, Augmented Reality (AR) and Radio Frequency Identification (RFID) has been proposed, and a prototype system has been developed. The system has navigation function of which an indication is superimposed directly on the user's view to help to find the designated valves by AR. It also has valve confirmation function by scanning RFID tag attached on the valve. In case of applying it to practical use, its information presentation device is important because it affects the task performance. In this study, therefore, a suitable information presentation device has been pursued by conducting subject experiments employing psychological experimental technique. The candidates of the devices are one-eye video see-through HMD (SCOPO) and both-eye video see-through HMD (Glasstron) as wearable system configuration, and tablet PC and compact TV as handheld system configuration. In the experiment, task completion time, number of errors, NASA-TLX score as subjects' mental workload and subjective usability questionnaire were measured when using the above devices. As the results, it was found that one-eye video see-through head mounted display, SCOPO was suitable device as wearable system configuration, and compact TV was suitable device as handheld system configuration. (author)

ITER SAFETY TASK NID-5D: Operational tritium loss and accident investigation for heat transport and water detritiation systems

International Nuclear Information System (INIS)

Kalyanam, K.M.; Fong, C.; Moledina, M.; Natalizio, A.

1995-02-01

The task objectives are to: a) determine major pathways for tritium loss during normal operation of the cooling systems and water detritiation system, b) estimate operational losses and environmental tritium releases from the heat transport and water detritiation systems of ITER, and c) prepare a preliminary Failure Modes and Effects Analysis (FMEA) for the ITER Water Detritiation System. The analysis will be used to estimate chronic environmental tritium releases (airborne and waterborne) for the ITER Cooling Systems and Water Detritiation System. The assessment will form the basis for demonstrating the acceptability of ITER for siting in the Early Safety and Environmental Characterization Study (ESECS), to be issued in early 1995. (author). 7 refs., 10 tabs., 11 figs

Adult-onset hyperthyroidism impairs spatial learning: possible involvement of mitogen-activated protein kinase signaling pathways.

Science.gov (United States)

Bitiktaş, Soner; Kandemir, Başak; Tan, Burak; Kavraal, Şehrazat; Liman, Narin; Dursun, Nurcan; Dönmez-Altuntaş, Hamiyet; Aksan-Kurnaz, Işil; Suer, Cem

2016-08-03

Given evidence that mitogen-activated protein kinase (MAPK) activation is part of the nongenomic actions of thyroid hormones, we investigated the possible consequences of hyperthyroidism for the cognitive functioning of adult rats. Young adult rats were treated with L-thyroxine or saline. Twenty rats in each group were exposed to Morris water maze testing, measuring their performance in a hidden-platform spatial task. In a separate set of rats not exposed to Morris water maze testing (untrained rats), the expression and phosphorylated levels of p38-MAPK and of its two downstream effectors, Elk-1 and cAMP response element-binding protein, were evaluated using quantitative reverse transcriptase-PCR and western blotting. Rats with hyperthyroidism showed delayed acquisition of learning compared with their wild-type counterparts, as shown by increased escape latencies and distance moved on the last two trials of daily training in the water maze. The hyperthyroid rats, however, showed no difference during probe trials. Western blot analyses of the hippocampus showed that hyperthyroidism increased phosphorylated p38-MAPK levels in untrained rats. Although our study is correlative in nature and does not exclude the contribution of other molecular targets, our findings suggest that the observed impairments in acquisition during actual learning in rats with hyperthyroidism may result from the increased phosphorylation of p38-MAPK.

Estradiol treatment in preadolescent females enhances adolescent spatial memory and differentially modulates hippocampal region-specific phosphorylated ERK labeling.

Science.gov (United States)

Wartman, Brianne C; Keeley, Robin J; Holahan, Matthew R

2012-10-24

Estrogen levels in rats are positively correlated with enhanced memory function and hippocampal dendritic spine density. There is much less work on the long-term effects of estradiol manipulation in preadolescent rats. The present work examined how injections of estradiol during postnatal days 19-22 (p19-22; preadolescence) affected water maze performance and hippocampal phosphorylated ERK labeling. To investigate this, half of the estradiol- and vehicle-treated female rats were trained on a water maze task 24h after the end of estradiol treatment (p23-27) while the other half was not trained. All female rats were tested on the water maze from p40 to p44 (adolescence) and hippocampal pERK1/2 labeling was assessed as a putative marker of neuronal plasticity. During adolescence, preadolescent-trained groups showed lower latencies than groups without preadolescent training. Retention data revealed lower latencies in both estradiol groups, whether preadolescent trained or not. Immunohistochemical detection of hippocampal pERK1/2 revealed elevations in granule cell labeling associated with the preadolescent trained groups and reductions in CA1 labeling associated with estradiol treatment. These results show a latent beneficial effect of preadolescent estradiol treatment on adolescent spatial performance and suggest an organizational effect of prepubescent exogenously applied estradiol. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Characterization of the Effects of Fatigue on the Central Nervous System (CNS) and Drug Therapies

National Research Council Canada - National Science Library

Mery, Laura

2007-01-01

.... The modified flower pot method of sleep disruption was used to induce fatigue. This study utilized hippocampal dependant tasks, the radial arm maze and the Barnes maze, to characterize the effects of sleep disruption fatigue...

Spatial delayed nonmatching-to-sample performances in long-living Ames dwarf mice.

Science.gov (United States)

Derenne, Adam; Brown-Borg, Holly M; Martner, Sarah; Wolff, Wendy; Frerking, Morgan

2014-01-17

Ames dwarf mice have an extended lifespan by comparison with normal mice. Behavioral testing has revealed that sometimes Ames dwarf mice also evince superior performances relative to normal mice, but in other cases they do not. In this experiment, Ames dwarf and normal mice were compared on a T-maze test and on a delayed nonmatching-to-sample variant of a T-maze test. On the simple T-maze, Ames dwarf and normal mice committed comparable numbers of errors. On the nonmatching-to-sample task, normal mice mastered the discrimination by the end of the experiment while Ames dwarf mice did not. The apparatus, distances traveled and session duration were equivalent between the two tasks. The poorer performances of Ames dwarf mice on the nonmatching-to-sample task suggests that Ames dwarf mice may not be as capable of learning relatively cognitively complex tasks as normal mice. © 2013.

Effects of novel tacrine-related cholinesterase inhibitors in the reversal of 3-quinuclidinyl benzilate-induced cognitive deficit in rats--Is there a potential for Alzheimer's disease treatment?

Science.gov (United States)

Misik, Jan; Korabecny, Jan; Nepovimova, Eugenie; Kracmarova, Alzbeta; Kassa, Jiri

2016-01-26

Inhibitors of cholinesterase are important drugs for therapy of Alzheimer's disease and the search for new modifications is extensive, including dual inhibitors or multi-target hybrid compounds. The aim of the present study was a preliminary evaluation of pro-cognitive effects of newly-developed 7-MEOTA-donepezil like hybrids (compounds no. 1 and 2) and N-alkylated tacrine derivatives (compounds no. 3 and 4) using an animal model of pharmacologically-induced cognitive deficit. Male Wistar rats were subjected to tests of learning and memory in a water maze and step-through passive avoidance task. Cognitive impairment was induced by 3-quinuclidinyl benzilate (QNB, 2mgkg(-1)), administered intraperitoneally 1h before training sessions. Cholinesterase inhibitors were administered as a single therapeutic dose following the QNB at 30min at the following dose rates; 1 (25.6mgkg(-1)), 2 (12.3mgkg(-1)), 3 (5.7mgkg(-1)), 4 (5.2mgkg(-1)). The decrease in total path within the 10-swim session (water maze), the preference for target quadrant (water maze) and the entrance latency (passive avoidance) were taken as indicators of learning ability in rats. The effects of novel compounds were compared to that of standards tacrine (5.2mgkg(-1)) and donepezil (2.65mgkg(-1)). QNB significantly impaired spatial navigation as well as fear learning. Generally, the performance of rats was improved when treated with novel inhibitors and this effect reached efficiency of standard donepezil at selected doses. There was a significant improvement in the groups treated with compounds 2 and 3 in all behavioral tasks. The rest of the novel compounds succeed in the passive avoidance test. In summary, the potential of novel inhibitors (especially compounds 2 and 3) was proved and further detailed evaluation of these compounds as potential drugs for Alzheimer's disease treatment is proposed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Clearing out a maze: A model of chemotactic motion in porous media

Science.gov (United States)

Schilling, Tanja; Voigtmann, Thomas

2017-12-01

We study the anomalous dynamics of a biased "hungry" (or "greedy") random walk on a percolating cluster. The model mimics chemotaxis in a porous medium: In close resemblance to the 1980s arcade game PAC-MA N ®, the hungry random walker consumes food, which is initially distributed in the maze, and biases its movement towards food-filled sites. We observe that the mean-squared displacement of the process follows a power law with an exponent that is different from previously known exponents describing passive or active microswimmer dynamics. The change in dynamics is well described by a dynamical exponent that depends continuously on the propensity to move towards food. It results in slower differential growth when compared to the unbiased random walk.

Endogenous IL-1 in Cognitive Function and Anxiety: A Study in IL-1RI−/− Mice

Science.gov (United States)

Murray, Carol L.; Obiang, Pauline; Bannerman, David; Cunningham, Colm

2013-01-01

Interleukin-1 (IL-1) is a key pro-inflammatory cytokine, produced predominantly by peripheral immune cells but also by glia and some neuronal populations within the brain. Its signalling is mediated via the binding of IL-1α or IL-1β to the interleukin-1 type one receptor (IL-1RI). IL-1 plays a key role in inflammation-induced sickness behaviour, resulting in depressed locomotor activity, decreased exploration, reduced food and water intake and acute cognitive deficits. Conversely, IL-1 has also been suggested to facilitate hippocampal-dependent learning and memory: IL-1RI−/− mice have been reported to show deficits on tasks of visuospatial learning and memory. We sought to investigate whether there is a generalised hippocampal deficit in IL-1RI−/− animals. Therefore, in the current study we compared wildtype (WT) mice to IL-1RI−/− mice using a variety of hippocampal-dependent learning and memory tasks, as well as tests of anxiety and locomotor activity. We found no difference in performance of the IL-1RI−/− mice compared to WT mice in a T-maze working memory task. In addition, the IL-1RI−/− mice showed normal learning in various spatial reference memory tasks including the Y-maze and Morris mater maze, although there was a subtle deficit in choice behaviour in a spatial discrimination, beacon watermaze task. IL-1RI−/− mice also showed normal memory for visuospatial context in the contextual fear conditioning paradigm. In the open field, IL-1RI−/− mice showed a significant increase in distance travelled and rearing behaviour compared to the WT mice and in the elevated plus-maze spent more time in the open arms than did the WT animals. The data suggest that, contrary to prior studies, IL-1RI−/− mice are not robustly impaired on hippocampal-dependent memory and learning but do display open field hyperactivity and decreased anxiety compared to WT mice. The results argue for a careful evaluation of the roles of endogenous IL-1 in

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.

Effect of intranasal manganese administration on neurotransmission and spatial learning in rats

International Nuclear Information System (INIS)

Blecharz-Klin, Kamilla; Piechal, Agnieszka; Joniec-Maciejak, Ilona; Pyrzanowska, Justyna; Widy-Tyszkiewicz, Ewa

2012-01-01

The effect of intranasal manganese chloride (MnCl 2 ·4H 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 2 ·4H 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.

Cognitive correlates of spatial navigation: Associations between executive functioning and the virtual Morris Water Task.

Science.gov (United States)

Korthauer, L E; Nowak, N T; Frahmand, M; Driscoll, I

2017-01-15

Although effective spatial navigation requires memory for objects and locations, navigating a novel environment may also require considerable executive resources. The present study investigated associations between performance on the virtual Morris Water Task (vMWT), an analog version of a nonhuman spatial navigation task, and neuropsychological tests of executive functioning and spatial performance in 75 healthy young adults. More effective vMWT performance (e.g., lower latency and distance to reach hidden platform, greater distance in goal quadrant on a probe trial, fewer path intersections) was associated with better verbal fluency, set switching, response inhibition, and ability to mentally rotate objects. Findings also support a male advantage in spatial navigation, with sex moderating several associations between vMWT performance and executive abilities. Overall, we report a robust relationship between executive functioning and navigational skill, with some evidence that men and women may differentially recruit cognitive abilities when navigating a novel environment. Copyright © 2016 Elsevier B.V. All rights reserved.

A Navigation Analysis Tool (NAT) to assess spatial behavior in open-field and structured mazes.

Science.gov (United States)

Jarlier, Frédéric; Arleo, Angelo; Petit, Géraldine H; Lefort, Julie M; Fouquet, Céline; Burguière, Eric; Rondi-Reig, Laure

2013-05-15

Spatial navigation calls upon mnemonic capabilities (e.g. remembering the location of a rewarding site) as well as adaptive motor control (e.g. fine tuning of the trajectory according to the ongoing sensory context). To study this complex process by means of behavioral measurements it is necessary to quantify a large set of meaningful parameters on multiple time scales (from milliseconds to several minutes), and to compare them across different paradigms. Moreover, the issue of automating the behavioral analysis is critical to cope with the consequent computational load and the sophistication of the measurements. We developed a general purpose Navigation Analysis Tool (NAT) that provides an integrated architecture consisting of a data management system (implemented in MySQL), a core analysis toolbox (in MATLAB), and a graphical user interface (in JAVA). Its extensive characterization of trajectories over time, from exploratory behavior to goal-oriented navigation with decision points using a wide range of parameters, makes NAT a powerful analysis tool. In particular, NAT supplies a new set of specific measurements assessing performances in multiple intersection mazes and allowing navigation strategies to be discriminated (e.g. in the starmaze). Its user interface enables easy use while its modular organization provides many opportunities of extension and customization. Importantly, the portability of NAT to any type of maze and environment extends its exploitation far beyond the field of spatial navigation. Copyright © 2013 Elsevier B.V. All rights reserved.

Search Strategies Used by Older Adults in a Virtual Reality Place Learning Task.

Science.gov (United States)

Davis, Rebecca L; Weisbeck, Catherine

2015-06-01

Older adults often have problems finding their way in novel environments such as senior living residences and hospitals. The purpose of this study was to examine the types of self-reported search strategies and cues that older adults use to find their way in a virtual maze. Healthy, independently living older adults (n = 129) aged 55-96 were tested in a virtual maze task over a period of 3 days in which they had to repeatedly find their way to a specified goal. They were interviewed about their strategies on days 1 and 3. Content analysis was used to identify the strategies and cues described by the participants in order to find their way. Strategies and cues used were compared among groups. The participants reported the use of multiple spatial and non-spatial strategies, and some of the strategies differed among age groups and over time. The oldest age group was less likely to use strategies such as triangulation and distance strategies. All participants used visual landmarks to find their way, but the use of geometric cues (corners) was used less by the older participants. These findings add to the theoretical understanding of how older adults find their way in complex environments. The understanding of how wayfinding changes with age is essential in order to design more supportive environments. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

ITER task D316 (1996): design review of isotope separation system (WBS 3.2 B) and water detritiation system (WBS 3.2 E)

International Nuclear Information System (INIS)

Sood, S.K.; Fong, C.

1997-05-01

The design review performed on the ITER Isotope Separation System and the Water Detritiation System are summarized. The objectives of the task are: to produce a Design Description Document for the Feed Treatment and Vacuum system for the Water Detritiation system; to review the process system operation and control philosophy for the Water Detritiation System; to review the equipment arrangement drawings where available. 1 fig., 3 refs

Sleep deprivation and time-on-task performance decrement in the rat psychomotor vigilance task.

Science.gov (United States)

Oonk, Marcella; Davis, Christopher J; Krueger, James M; Wisor, Jonathan P; Van Dongen, Hans P A

2015-03-01

The rat psychomotor vigilance task (rPVT) was developed as a rodent analog of the human psychomotor vigilance task (hPVT). We examined whether rPVT performance displays time-on-task effects similar to those observed on the hPVT. The rPVT requires rats to respond to a randomly presented light stimulus to obtain a water reward. Rats were water deprived for 22 h prior to each 30-min rPVT session to motivate performance. We analyzed rPVT performance over time on task and as a function of the response-stimulus interval, at baseline and after sleep deprivation. The study was conducted in an academic research vivarium. Male Long-Evans rats were trained to respond to a 0.5 sec stimulus light within 3 sec of stimulus onset. Complete data were available for n = 20 rats. Rats performed the rPVT for 30 min at baseline and after 24 h total sleep deprivation by gentle handling. Compared to baseline, sleep deprived rats displayed increased performance lapses and premature responses, similar to hPVT lapses of attention and false starts. However, in contrast to hPVT performance, the time-on-task performance decrement was not significantly enhanced by sleep deprivation. Moreover, following sleep deprivation, rPVT response times were not consistently increased after short response-stimulus intervals. The rPVT manifests similarities to the hPVT in global performance outcomes, but not in post-sleep deprivation effects of time on task and response-stimulus interval. © 2015 Associated Professional Sleep Societies, LLC.

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.

OPTIMASI ALGHORITMA BREADTH FIRST SEARCH PADA GAME ENGINE 3D THIRD PERSON SHOOTER MAZE BERBASIS AGEN CERDAS ANDROID

Directory of Open Access Journals (Sweden)

Astrid Novita Putri

2016-11-01

Full Text Available Game is currently very popular in the community at large, one of which is the game third person shooter (TPS which can be run through a mobile phone or computer, making it very easy and affordable, one thrid person shooter game 3D maze.The labyrinth is a game to find the right path to achieve the objectives which the way players experience many obstacles to destination, so spend a lot of time,then in need of a settlement in order to facilitate the player in completing the levels on every obstacle, in need of a alghoritm Breadth First Search for ease in completing permainan.Cara employment levels every alghoritm Breadth First Search is a search method that starts with the roots off the road to the next.This search is done by looking at all the nodes or vertices have the same level to determine the final outcome at that level,if they do not find the will to move to the next level. so that the process backtrackto re-find the right path to achieve goals the appropriate time.   Keyword: Games, Third person, Shooter, Maze, Breadth First Search.

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

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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.

Animal model of dementia induced by entorhinal synaptic damage and partial restoration of cognitive deficits by BDNF and carnitine.

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Ando, Susumu; Kobayashi, Satoru; Waki, Hatsue; Kon, Kazuo; Fukui, Fumiko; Tadenuma, Tomoko; Iwamoto, Machiko; Takeda, Yasuo; Izumiyama, Naotaka; Watanabe, Kazutada; Nakamura, Hiroaki

2002-11-01

A rat dementia model with cognitive deficits was generated by synapse-specific lesions using botulinum neurotoxin (BoNTx) type B in the entorhinal cortex. To detect cognitive deficits, different tasks were needed depending upon the age of the model animals. Impaired learning and memory with lesions were observed in adult rats using the Hebb-Williams maze, AKON-1 maze and a continuous alternation task in T-maze. Cognitive deficits in lesioned aged rats were detected by a continuous alternation and delayed non-matching-to-sample tasks in T-maze. Adenovirus-mediated BDNF gene expression enhanced neuronal plasticity, as revealed by behavioral tests and LTP formation. Chronic administration of carnitine over time pre- and post-lesions seemed to partially ameliorate the cognitive deficits caused by the synaptic lesion. The carnitine-accelerated recovery from synaptic damage was observed by electron microscopy. These results demonstrate that the BoNTx-lesioned rat can be used as a model for dementia and that cognitive deficits can be alleviated in part by BDNF gene transfer or carnitine administration. Copyright 2002 Wiley-Liss, Inc.

Dahl (S × R) rat congenic strain analysis confirms and defines a chromosome 17 spatial navigation quantitative trait locus to <10 Mbp.

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Herrera, Victoria L; Pasion, Khristine A; Tan, Glaiza A; Ruiz-Opazo, Nelson

2013-01-01

A quantitative trait locus (QTL) linked with ability to find a platform in the Morris Water Maze (MWM) was located on chromosome 17 (Nav-5 QTL) using intercross between Dahl S and Dahl R rats. We developed two congenic strains, S.R17A and S.R17B introgressing Dahl R-chromosome 17 segments into Dahl S chromosome 17 region spanning putative Nav-5 QTL. Performance analysis of S.R17A, S.R17B and Dahl S rats in the Morris water maze (MWM) task showed a significantly decreased spatial navigation performance in S.R17B congenic rats when compared with Dahl S controls (P = 0.02). The S.R17A congenic segment did not affect MWM performance delimiting Nav-5 to the chromosome 17 65.02-74.66 Mbp region. Additional fine mapping is necessary to identify the specific gene variant accounting for Nav-5 effect on spatial learning and memory in Dahl rats.

Dahl (S × R rat congenic strain analysis confirms and defines a chromosome 17 spatial navigation quantitative trait locus to <10 Mbp.

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Victoria L Herrera

Full Text Available A quantitative trait locus (QTL linked with ability to find a platform in the Morris Water Maze (MWM was located on chromosome 17 (Nav-5 QTL using intercross between Dahl S and Dahl R rats. We developed two congenic strains, S.R17A and S.R17B introgressing Dahl R-chromosome 17 segments into Dahl S chromosome 17 region spanning putative Nav-5 QTL. Performance analysis of S.R17A, S.R17B and Dahl S rats in the Morris water maze (MWM task showed a significantly decreased spatial navigation performance in S.R17B congenic rats when compared with Dahl S controls (P = 0.02. The S.R17A congenic segment did not affect MWM performance delimiting Nav-5 to the chromosome 17 65.02-74.66 Mbp region. Additional fine mapping is necessary to identify the specific gene variant accounting for Nav-5 effect on spatial learning and memory in Dahl rats.

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.

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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. © 2013.

Impairments of exploration and memory after systemic or prelimbic D1-receptor antagonism in rats

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Clausen, Bettina; Schachtman, Todd R.; Mark, Louise T.

2011-01-01

to examine the effects on memory: cross-maze and object recognition task. Systemic administration reduced spatial exploration in cross-maze as well as in an open field test, and also reduced object exploration. Spatial (hippocampus-dependent) short-term memory was inhibited in the cross-maze and non......-spatial short-term object retention was also impaired. In contrast to these systemic effects, bilateral injections of SCH23390 into the prelimbic cortices altered neither spatial nor object exploration, but did inhibit short-term memory in both cross-maze and object recognition task. Therefore, the inhibiting......D1-receptor antagonism is known to impair rodent memory but also inhibits spontaneous exploration of stimuli to be remembered. Hypo-exploration could contribute to impaired memory by influencing event processing. In order to explore this effect, the D1 receptor antagonist, SCH23390...

Erythropoietin improves place learning in fimbria-fornix-transected rats and modifies the search pattern of normal rats

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Mogensen, Jesper; Miskowiak, Kamilla; Sørensen, Thomas Alrik

2004-01-01

administration of EPO significantly improves the posttraumatic functional recovery of the presently studied place learning task after transections of the fimbria-fornix. Additionally, administration of EPO influences the strategy, although not quality, of task solution in normal (sham-operated) rats.......The acquisition of a water-maze-based allocentric place learning task was studied in four groups of rats: two groups subjected to bilateral transections of the fimbria-fornix and two groups undergoing a sham control operation. At the moment of surgery all animals were given one systemic......-associated impairment. The two sham-operated groups did not differ with respect to the proficiency of task acquisition. But administration of EPO to intact animals caused a significant modification of swim patterns-apparently reflecting a somewhat modified strategy of task solution. It is concluded that systemic...

Spatial memory extinction: a c-Fos protein mapping study.

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Méndez-Couz, M; Conejo, N M; Vallejo, G; Arias, J L

2014-03-01

While the neuronal basis of spatial memory consolidation has been thoroughly studied, the substrates mediating the process of extinction remain largely unknown. This study aimed to evaluate the functional contribution of selected brain regions during the extinction of a previously acquired spatial memory task in the Morris water maze. For that purpose, we used adult male Wistar rats trained in a spatial reference memory task. Learning-related changes in c-Fos inmunoreactive cells after training were evaluated in cortical and subcortical regions. Results show that removal of the hidden platform in the water maze induced extinction of the previously reinforced escape behavior after 16 trials, without spontaneous recovery 24h later. Extinction was related with significantly higher numbers of c-Fos positive nuclei in amygdala nuclei and prefrontal cortex. On the other hand, the lateral mammillary bodies showed higher number of c-Fos positive cells than the control group. Therefore, in contrast with the results obtained in studies of classical conditioning, we show the involvement of diencephalic structures mediating this kind of learning. In summary, our findings suggest that medial prefrontal cortex, the amygdala complex and diencephalic structures like the lateral mammillary nuclei are relevant for the extinction of spatial memory. Copyright © 2013 Elsevier B.V. All rights reserved.

Reduced spatial learning in mice infected with the nematode, Heligmosomoides polygyrus.

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Kavaliers, M; Colwell, D D

1995-06-01

Parasite modification of host behaviour influences a number of critical responses, but little is known about the effects on host spatial abilities. This study examined the effects of infection with the intestinal trichostrongylid nematode, Heligmosomoides polygyrus, on spatial water maze learning by male laboratory mice, Mus musculus. In this task individual mice had to learn the spatial location of a submerged hidden platform using extramaze visual cues. Determinations of spatial performance were made on day 19 post-infection with mice that had been administered either 50 or 200 infective larvae of H. polygyrus. The infected mice displayed over 1 day of testing (6 blocks of 4 trials) significantly poorer acquisition and retention of the water maze task than either sham-infected or control mice, with mice that had received 200 infective larvae displaying significantly poorer spatial performance than individuals receiving 50 larvae. The decrease in spatial learning occurred in the absence of either any symptoms of illness and malaise, or any evident motor, visual and motivational impairments. It is suggested that in this single host system the parasitic infection-induced decrease in spatial learning arises as a side-effect of the host's immunological and neuromodulatory responses and represents a fitness cost of response to infection.

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

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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.

Down-Regulation of Homer1b/c Protects Against Chemically Induced Seizures Through Inhibition of mTOR Signaling

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Lei Cao

2015-03-01

Full Text Available Background: Homer is a family of post synaptic density proteins functionally and physically attached to target proteins at proline-rich sequences. Reducing Homer1b/c expression has been shown in previous studies to be protective against excitotoxic insults, implicating Homer1b/c in the physiological regulation of aberrant neuronal excitability. Methods: To test the efficacy of a Homer1b/c reducing therapy for disorders with a detrimental hyperexcitability profile in mice, we used small interfere RNA (siRNA to decrease endogenous Homer1b/c expression in mouse hippocampus. The baseline motor and cognitive behavior was measured by sensorimotor tests, Morris water maze and elevated plus maze tasks. The anti-epileptic effects of Homer1b/c knockdown were determined in two chemically induced seizure models induced by Picrotoxin (PTX or pentylenetetrazole (PTZ administration. Results: The results of sensorimotor tests, Morris water maze and elevated plus maze tasks showed that Homer1b/c reduction had no effect on baseline motor or cognitive behavior. In two chemically induced seizure models, mice with reduced Homerb/c protein had less severe seizures than control mice. Total Homer1b/c protein levels and seizure severity were highly correlated, such that those mice with the most severe seizures also had the highest levels of Homer1b/c. In addition, the phosphorylation of mammalian target of rapamycin (mTOR and its target protein S6 was significantly inhibited in Homer1b/c down-regulated mice. Homer1b/c knockdown-induced inhibition of mTOR pathway was partially ablated by the metabotropic glutamate receptor 5 (mGluR5 agonist CHPG. Conclusion: Our results demonstrate that endogenous Homer1b/c is integral for regulating neuronal hyperexcitability in adult animals and suggest that reduction of Homer1b/c could protect against chemically induced seizures through inhibition mTOR pathway.

Over-expression of two different forms of the alpha-secretase ADAM10 affects learning and memory in mice.

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Schmitt, Ulrich; Hiemke, Christoph; Fahrenholz, Falk; Schroeder, Anja

2006-12-15

Members of the ADAM family (adisintegrin and metalloprotease) are the main candidates for physiologically relevant alpha-secretases. The alpha-secretase cleaves in the non-amyloidogenic pathway the amyloid precursor protein within the region of the Abeta peptides preventing their aggregation in the brain. The increase of alpha-secretase activity in the brain provides a plausible strategy to prevent Abeta formation. Concerning this possibility two transgenic mouse lines (FVB/N) have been created: mice over-expressing the bovine form of the alpha-secretase (ADAM10) and mice over-expressing an inactive form of the alpha-secretase (ADAM10-E348A-HA; ADAM10-dn). For behavioral examination a F1 generation of transgenic mice (C57Bl/6 x FVB/N (tg)) was generated and compared to wild type F1 generation (C57Bl/6 x FVB/N). Behavior was characterized in the following tasks: standard open field, enriched open field, elevated plus-maze, and the Morris water maze hidden platform task. Concerning basal activity, exploration, and anxiety, transgenic mice behaved similar to controls. With respect to learning and memory both transgenic lines showed a significant deficit compared to controls. ADAM10 mice however, showed thigmotaxis with passive floating behavior in the Morris water maze indicating differences in motivation, whereas, ADAM10-dn mice displayed an inconspicuous but limited goal-directed search pattern. Thus variation of the enzymatic activity of alpha-secretase ADAM10 alters learning and memory differentially. Nevertheless, it could be concluded that both, ADAM10 and ADAM10-dn mice are suitable control mice for the assessment of alpha-secretase-related effects in animal models of Alzheimer's disease.

The effects of the administration of two different doses of manganese on short-term spatial memory and anxiety-like behavior in rats

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Hogas M.

2011-01-01

Full Text Available Manganese is a very well known neurotoxic agent. It has been mainly linked to impaired motor skills and disturbed psychomotor development. However, very few aspects are known about the cognitive deficits and behavioral consequences of chronic manganese exposure. In this context, we report herein our findings regarding short-term spatial memory, motor and anxiety-like behavior assessments in male Wistar rats exposed for 45 days to two different doses (3 mg/kg b.w., i.p. and 10 mg/kg b.w., i.p. of manganese. Behavior testing (Y-maze task and elevated plus maze was performed after 45 days of manganese administration. Chronic manganese exposure in Wistar rats led to behavioral alterations consisting of cognitive deficiencies in the Y-maze task and anxiety/compulsive-like behaviors in the elevated plus maze, but no motor disturbances as tested by the number of arm entries in the Y-maze. Additional work is necessary to understand the longterm effects of different doses and dosing regimens of manganese on cognitive/affective and motor functioning.

Lewis and Fischer 344 rats as a model for genetic differences in spatial learning and memory: Cocaine effects.

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Fole, Alberto; Miguéns, Miguel; Morales, Lidia; González-Martín, Carmen; Ambrosio, Emilio; Del Olmo, Nuria

2017-06-02

Lewis (LEW) and Fischer 344 (F344) rats are considered a model of genetic vulnerability to drug addiction. We previously showed important differences in spatial learning and memory between them, but in contrast with previous experiments demonstrating cocaine-induced enhanced learning in Morris water maze (MWM) highly demanding tasks, the eight-arm radial maze (RAM) performance was not modified either in LEW or F344 rats after chronic cocaine treatment. In the present work, chronically cocaine-treated LEW and F344 adult rats have been evaluated in learning and memory performance using the Y-maze, two RAM protocols that differ in difficulty, and a reversal protocol that tests cognitive flexibility. After one of the RAM protocols, we quantified dendritic spine density in hippocampal CA1 neurons and compared it to animals treated with cocaine but not submitted to RAM. LEW cocaine treated rats showed a better performance in the Y maze than their saline counterparts, an effect that was not evident in the F344 strain. F344 rats significantly took more time to learn the RAM task and made a greater number of errors than LEW animals in both protocols tested, whereas cocaine treatment induced deleterious effects in learning and memory in the highly difficult protocol. Moreover, hippocampal spine density was cocaine-modulated in LEW animals whereas no effects were found in F344 rats. We propose that differences in addictive-like behavior between LEW and F344 rats could be related to differences in hippocampal learning and memory processes that could be on the basis of individual vulnerability to cocaine addiction. Copyright © 2017 Elsevier Inc. All rights reserved.

Spatial learning, monoamines and oxidative stress in rats exposed to 900 MHz electromagnetic field in combination with iron overload.

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Maaroufi, Karima; Had-Aissouni, Laurence; Melon, Christophe; Sakly, Mohsen; Abdelmelek, Hafedh; Poucet, Bruno; Save, Etienne

2014-01-01

The increasing use of mobile phone technology over the last decade raises concerns about the impact of high frequency electromagnetic fields (EMF) on health. More recently, a link between EMF, iron overload in the brain and neurodegenerative disorders including Parkinson's and Alzheimer's diseases has been suggested. Co-exposure to EMF and brain iron overload may have a greater impact on brain tissues and cognitive processes than each treatment by itself. To examine this hypothesis, Long-Evans rats submitted to 900 MHz exposure or combined 900 MHz EMF and iron overload treatments were tested in various spatial learning tasks (navigation task in the Morris water maze, working memory task in the radial-arm maze, and object exploration task involving spatial and non spatial processing). Biogenic monoamines and metabolites (dopamine, serotonin) and oxidative stress were measured. Rats exposed to EMF were impaired in the object exploration task but not in the navigation and working memory tasks. They also showed alterations of monoamine content in several brain areas but mainly in the hippocampus. Rats that received combined treatment did not show greater behavioral and neurochemical deficits than EMF-exposed rats. None of the two treatments produced global oxidative stress. These results show that there is an impact of EMF on the brain and cognitive processes but this impact is revealed only in a task exploiting spontaneous exploratory activity. In contrast, there are no synergistic effects between EMF and a high content of iron in the brain. Copyright © 2013 Elsevier B.V. All rights reserved.

The effect of psilocin on memory acquisition, retrieval and consolidation in rat.

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Lukas eRambousek

2014-05-01

Full Text Available The involvement of the serotonin system in the pathophysiology of schizophrenia has been elucidated by experiments with hallucinogens. Application of a hallucinogen to humans leads to changes in perception, cognition, emotions and induction of psychotic-like symptoms that resemble symptoms of schizophrenia. In rodent studies, their acute administration affects sensorimotor gating, locomotor activity, social behavior and cognition including working memory, the phenotypes are considered as an animal model of schizophrenia. The complexity and singularity of human cognition raises questions about the validity of animal models utilizing agonists of 5-HT2A receptors. The present study thus investigated the effect of psilocin on memory acquisition, reinforced retrieval and memory consolidation in rats. Psilocin is a main metabolite of psilocybin acting as an agonist at 5-HT2A receptors with a contribution of 5-HT2C and 5-HT1A receptors. First, we tested the effect of psilocin on the acquisition of a Carousel maze, a spatial task requiring navigation using distal cues, attention and cognitive coordination. Psilocin significantly impaired the acquisition of the Carousel Maze at both doses (1 and 4 mg/kg. The higher dose of psilocin blocked the learning processes even in an additional session when the rats received only saline. Next, we examined the effect of psilocin on reinforced retrieval and consolidation in the Morris water maze (MWM. The dose of 4 mg/kg disrupted reinforced retrieval in the Morris water maze. However, the application of a lower dose was without any significant effect. Finally, neither the low nor high dose of psilocin injected post-training caused a deficit in memory consolidation in the MWM. Taken together, the psilocin dose dependently impaired the acquisition of the Carousel maze and reinforced retrieval in MWM; however, it had no effect on memory consolidation.

Learning context modulates aversive taste strength in honey bees.

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de Brito Sanchez, Maria Gabriela; Serre, Marion; Avarguès-Weber, Aurore; Dyer, Adrian G; Giurfa, Martin

2015-03-01

The capacity of honey bees (Apis mellifera) to detect bitter substances is controversial because they ingest without reluctance different kinds of bitter solutions in the laboratory, whereas free-flying bees avoid them in visual discrimination tasks. Here, we asked whether the gustatory perception of bees changes with the behavioral context so that tastes that are less effective as negative reinforcements in a given context become more effective in a different context. We trained bees to discriminate an odorant paired with 1 mol l(-1) sucrose solution from another odorant paired with either distilled water, 3 mol l(-1) NaCl or 60 mmol l(-1) quinine. Training was either Pavlovian [olfactory conditioning of the proboscis extension reflex (PER) in harnessed bees], or mainly operant (olfactory conditioning of free-walking bees in a Y-maze). PER-trained and maze-trained bees were subsequently tested both in their original context and in the alternative context. Whereas PER-trained bees transferred their choice to the Y-maze situation, Y-maze-trained bees did not respond with a PER to odors when subsequently harnessed. In both conditioning protocols, NaCl and distilled water were the strongest and the weakest aversive reinforcement, respectively. A significant variation was found for quinine, which had an intermediate aversive effect in PER conditioning but a more powerful effect in the Y-maze, similar to that of NaCl. These results thus show that the aversive strength of quinine varies with the learning context, and reveal the plasticity of the bee's gustatory system. We discuss the experimental constraints of both learning contexts and focus on stress as a key modulator of taste in the honey bee. Further explorations of bee taste are proposed to understand the physiology of taste modulation in bees. © 2015. Published by The Company of Biologists Ltd.

Effects of environmentally differential rearing upon maze performance in prenatally irradiated microcephalic rats

International Nuclear Information System (INIS)

Seo, M.L.; Inouye, M.; Kiyono, S.; Shibagaki, M.

1982-01-01

Pregnant rats received 100 rads of X-irradiation on day 17 of gestation. Control pregnant rats were sham-irradiated on the same gestation day. The male offspring were reared under environmentally enriched, standard colony, and impoverished conditions for 30 days after weaning. Then the Hebb-Williams maze test was carried out. All the prenatally X-irradiated rats were microcephalic: their mean cerebral wet weight was 15.5% less than controls. The effect of X-irradiation was not significant in error scores and running times, whereas the effect of environment was significant in these items; initial and total error scores and running times were decreased in enriched groups compared to impoverished groups in controls as well as in X-irradiated animals

Age-dependent effect of high cholesterol diets on anxiety-like behavior in elevated plus maze test in rats.

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Hu, Xu; Wang, Tao; Luo, Jia; Liang, Shan; Li, Wei; Wu, Xiaoli; Jin, Feng; Wang, Li

2014-09-01

Cholesterol is an essential component of brain and nerve cells and is essential for maintaining the function of the nervous system. Epidemiological studies showed that patients suffering from anxiety disorders have higher serum cholesterol levels. In this study, we investigated the influence of high cholesterol diet on anxiety-like behavior in elevated plus maze in animal model and explored the relationship between cholesterol and anxiety-like behavior from the aspect of central neurochemical changes. Young (3 weeks old) and adult (20 weeks old) rats were given a high cholesterol diet for 8 weeks. The anxiety-like behavior in elevated plus maze test and changes of central neurochemical implicated in anxiety were measured. In young rats, high cholesterol diet induced anxiolytic-like behavior, decreased serum corticosterone (CORT), increased hippocampal brain-derived neurotrophic factor (BDNF), increased hippocampal mineralocorticoid receptor (MR) and decreased glucocorticoid receptor (GR). In adult rats, high cholesterol diet induced anxiety-like behavior and increase of serum CORT and decrease of hippocampal BDNF comparing with their respective control group that fed the regular diet. High cholesterol diet induced age-dependent effects on anxiety-like behavior and central neurochemical changes. High cholesterol diet might affect the central nervous system (CNS) function differently, and resulting in different behavior performance of anxiety in different age period.

Treadmill running prevents age-related memory deficit and alters neurotrophic factors and oxidative damage in the hippocampus of Wistar rats.

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Vanzella, Cláudia; Neves, Juliana Dalibor; Vizuete, Adriana Fernanda; Aristimunha, Dirceu; Kolling, Janaína; Longoni, Aline; Gonçalves, Carlos Alberto Saraiva; Wyse, Angela T S; Netto, Carlos Alexandre

2017-09-15

Clinical and pre-clinical studies indicate that exercise is beneficial to many aspects of brain function especially during aging. The present study investigated the effects of a treadmill running protocol in young (3month-old) and aged (22month-old) male Wistar rats, on: I) cognitive function, as assessed by spatial reference memory in the Morris water maze; II) oxidative stress parameters and the expression of neurotrophic factors BDNF, NT-3, IGF-1 and VEGF in the hippocampus. Animals of both ages were assigned to sedentary (non-exercised) and exercised (20min of daily running sessions, 3 times per week for 4weeks) groups. Cognition was assessed by a reference memory task run in the Morris water maze; twenty four hours after last session of behavioral testing hippocampi were collected for biochemical analysis. Results demonstrate that the moderate treadmill running exercise: I) prevented age-related deficits in reference memory in the Morris water maze; II) prevented the age-related increase of reactive oxygen species levels and lipid peroxidation in the hippocampus; III) caused an increase of BDNF, NT-3 and IGF-1 expression in the hippocampus of aged rats. Taken together, results suggest that both exercise molecular effects, namely the reduction of oxidative stress and the increase of neurotrophic factors expression in the hippocampus, might be related to its positive effect on memory performance in aged rats. Copyright © 2017 Elsevier B.V. All rights reserved.

Spatial Navigation in Complex and Radial Mazes in APP23 Animals and Neurotrophin Signaling as a Biological Marker of Early Impairment

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Hellweg, Rainer; Huber, Roman; Kuhl, Alexander; Riepe, Matthias W.; Lohmann, Peter

2006-01-01

Impairment of hippocampal function precedes frontal and parietal cortex impairment in human Alzheimer's disease(AD). Neurotrophins are critical for behavioral performance and neuronal survival in AD. We used complex and radial mazes to assess spatial orientation and learning in wild-type and B6-Tg(ThylAPP)23Sdz (APP23) animals, a transgenic mouse…

An automated Y-maze based on a reduced instruction set computer (RISC) microcontroller for the assessment of continuous spontaneous alternation in rats.

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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.

[Effects of nootropic drugs on behavior of BALB/c and C57BL/6 mice in the exploratory cross-maze test].

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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).

Stress Hormone Enhancement of OP-Induced Neuroinflammation as an Animal Model of GWI: The Role of Toll-like Receptors and Plasticity

Science.gov (United States)

2017-09-01

experience with this paradigm. In this test a mouse must learn the location of an escape platform by swimming in a pool of water at room temperature ... learning employed instead of the Barnes maze (also a spatial learning paradigm) specified in Major Task 7. There is a wealth of information in the...shown in Figure 1A for the latency measure, which clearly decreased across acquisition trials as the animals learned the hidden platform location (the

Hippocampal development and the dissociation of cognitive-spatial mapping from motor performance [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Bryan D. Devan

2015-09-01

Full Text Available The publication of a recent article in F1000Research has led to discussion of, and correspondence on a broader issue that has a long history in the fields of neuroscience and psychology.  Namely, is it possible to separate the cognitive components of performance, in this case spatial behavior, from the motoric demands of a task?  Early psychological experiments attempted such a dissociation by studying a form of spatial maze learning where initially rats were allowed to explore a complex maze, termed “latent learning,” before reinforcement was introduced.  Those rats afforded the latent learning experience solved the task faster than those that were not, implying that cognitive map learning during exploration aided in the performance of the task once a motivational component was introduced.  This form of latent learning was interpreted as successfully demonstrating that an exploratory cognitive map component was acquired irrespective of performing a learned spatial response under deprivation/motivational conditions.  The neural substrate for cognitive learning was hypothesized to depend on place cells within the hippocampus.  Subsequent behavioral studies attempted to directly eliminate the motor component of spatial learning by allowing rats to passively view the distal environment before performing any motor response using a task that is widely considered to be hippocampal-dependent.  Latent learning in the water maze, using a passive placement procedure has met with mixed results.  One constraint on viewing cues before performing a learned swimming response to a hidden goal has been the act of dynamically viewing distal cues while moving through a part of the environment where an optimal learned spatial escape response would be observed.  We briefly review these past findings obtained with adult animals to the recent efforts of establishing a “behavioral topology” separating cognitive-spatial learning from tasks differing in

Hippocampal development and the dissociation of cognitive-spatial mapping from motor performance [version 1; referees: 2 approved

Directory of Open Access Journals (Sweden)

Bryan D. Devan

2015-08-01

Full Text Available The publication of a recent article in F1000Research has led to discussion of, and correspondence on a broader issue that has a long history in the fields of neuroscience and psychology.  Namely, is it possible to separate the cognitive components of performance, in this case spatial behavior, from the motoric demands of a task?  Early psychological experiments attempted such a dissociation by studying a form of spatial maze learning where initially rats were allowed to explore a complex maze, termed “latent learning,” before reinforcement was introduced.  Those rats afforded the latent learning experience solved the task faster than those that were not, implying that cognitive map learning during exploration aided in the performance of the task once a motivational component was introduced.  This form of latent learning was interpreted as successfully demonstrating that an exploratory cognitive map component was acquired irrespective of performing a learned spatial response under deprivation/motivational conditions.  The neural substrate for cognitive learning was hypothesized to depend on place cells within the hippocampus.  Subsequent behavioral studies attempted to directly eliminate the motor component of spatial learning by allowing rats to passively view the distal environment before performing any motor response using a task that is widely considered to be hippocampal-dependent.  Latent learning in the water maze, using a passive placement procedure has met with mixed results.  One constraint on viewing cues before performing a learned swimming response to a hidden goal has been the act of dynamically viewing distal cues while moving through a part of the environment where an optimal learned spatial escape response would be observed.  We briefly review these past findings obtained with adult animals to the recent efforts of establishing a “behavioral topology” separating cognitive-spatial learning from tasks differing in

DAILY RUNNING PROMOTES SPATIAL LEARNING AND MEMORY IN RATS

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HojjatAllah Alaei

2007-12-01

Full Text Available 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 < 0.05. The benefits in these tests were lost in three days, if the daily running session was abandoned. In group D with acute treadmill running (8 days exercise only the difference between the Group A disappeared in one week and benefit seemed to be obtained in comparison with the controls without running program. In conclusion the chronic and daily running exercises promoted learning and memory in Morris water maze, but the benefits were lost in few days without daily running sessions in adult rats

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

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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…

A low noise remotely controllable wireless telemetry system for single-unit recording in rats navigating in a vertical maze.

Science.gov (United States)

Chen, Hsin-Yung; Wu, Jin-Shang; Hyland, Brian; Lu, Xiao-Dong; Chen, Jia Jin Jason

2008-08-01

The use of cables for recording neural activity limits the scope of behavioral tests used in conscious free-moving animals. Particularly, cable attachments make it impossible to record in three-dimensional (3D) mazes where levels are vertically stacked or in enclosed spaces. Such environments are of particular interest in investigations of hippocampal place cells, in which neural activity is correlated with spatial position in the environment. We developed a flexible miniaturized Bluetooth-based wireless data acquisition system. The wireless module included an 8-channel analogue front end, digital controller, and Bluetooth transceiver mounted on a backpack. Our bidirectional wireless design allowed all data channels to be previewed at 1 kHz sample rate, and one channel, selected by remote control, to be sampled at 10 kHz. Extracellular recordings of neuronal activity are highly susceptible to ambient electrical noise due to the high electrode impedance. Through careful design of appropriate shielding and hardware configuration to avoid ground loops, mains power and Bluetooth hopping frequency noise were reduced sufficiently to yield signal quality comparable to those recorded by wired systems. With this system we were able to obtain single-unit recordings of hippocampal place cells in rats running an enclosed vertical maze, over a range of 5 m.

Does Chronic Unpredictable Stress during Adolescence Affect Spatial Cognition in Adulthood?

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Chaby, Lauren E; Sheriff, Michael J; Hirrlinger, Amy M; Lim, James; Fetherston, Thomas B; Braithwaite, Victoria A

2015-01-01

Spatial abilities allow animals to retain and cognitively manipulate information about their spatial environment and are dependent upon neural structures that mature during adolescence. Exposure to stress in adolescence is thought to disrupt neural maturation, possibly compromising cognitive processes later in life. We examined whether exposure to chronic unpredictable stress in adolescence affects spatial ability in late adulthood. We evaluated spatial learning, reference and working memory, as well as long-term retention of visuospatial cues using a radial arm water maze. We found that stress in adolescence decreased the rate of improvement in spatial learning in adulthood. However, we found no overall performance impairments in adult reference memory, working memory, or retention caused by adolescent-stress. Together, these findings suggest that adolescent-stress may alter the strategy used to solve spatial challenges, resulting in performance that is more consistent but is not refined by incorporating available spatial information. Interestingly, we also found that adolescent-stressed rats showed a shorter latency to begin the water maze task when re-exposed to the maze after an overnight delay compared with control rats. This suggests that adolescent exposure to reoccurring stressors may prepare animals for subsequent reoccurring challenges. Overall, our results show that stress in adolescence does not affect all cognitive processes, but may affect cognition in a context-dependent manner.

Mozart, Mozart Rhythm and Retrograde Mozart Effects: Evidences from Behaviours and Neurobiology Bases.

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Xing, Yingshou; Xia, Yang; Kendrick, Keith; Liu, Xiuxiu; Wang, Maosen; Wu, Dan; Yang, Hua; Jing, Wei; Guo, Daqing; Yao, Dezhong

2016-01-21

The phenomenal finding that listening to Mozart K.448 enhances performance on spatial tasks has motivated a continuous surge in promoting music education over the past two decades. But there have been inconsistent reports in previous studies of the Mozart effect. Here conducted was a systematic study, with Mozart and retrograde Mozart music, Mozart music rhythm and pitch, behaviours and neurobiology tests, rats and humans subjects. We show that while the Mozart K.448 has positive cognitive effects, the retrograde version has a negative effect on rats' performance in the Morris water maze test and on human subjects' performance in the paper folding and cutting test and the pencil-and-paper maze test. Such findings are further confirmed by subsequent immunohistochemical analyses in rats on the neurogenesis and protein levels of BDNF and its receptor, TrkB. Furthermore, when the rhythm and pitch of the normal and retrograde Mozart music are manipulated independently, the learning performance of the rats in the Morris water maze test indicated that rhythm is a crucial element in producing the behavioural effects. These findings suggest that the nature of Mozart effect is the Mozart rhythm effect, and indicate that different music may have quite different to opposite effects. Further study on rhythm effect may provide clues to understand the common basis over animals from rats to humans.

Behavioral phenotyping of mice in pharmacological and toxicological research.

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Karl, Tim; Pabst, Reinhard; von Hörsten, Stephan

2003-07-01

The evaluation of behavioral effects is an important component for the in vivo screening of drugs or potentially toxic compounds in mice. Ideally, such screening should be composed of monitoring general health, sensory functions, and motor abilities, right before specific behavioral domains are tested. A rational strategy in the design and procedure of testing as well as an effective composition of different well-established and reproducible behavioral tests can minimize the risk of false positive and false negative results in drug screening. In the present review we describe such basic considerations in planning experiments, selecting strains of mice, and propose groups of behavioral tasks suitable for a reliable detection of differences in specific behavioral domains in mice. Screening of general health and neurophysiologic functions (reflexes, sensory abilities) and motor function (pole test, wire hang test, beam walking, rotarod, accelerod, and footprint) as well as specific hypothesis-guided testing in the behavioral domains of learning and memory (water maze, radial maze, conditioned fear, and avoidance tasks), emotionality (open field, hole board, elevated plus maze, and object exploration), nociception (tail flick, hot plate), psychiatric-like conditions (porsolt swim test, acoustic startle response, and prepulse inhibition), and aggression (isolation-induced aggression, spontaneous aggression, and territorial aggression) are described in further detail. This review is designed to describe a general approach, which increases reliability of behavioral screening. Furthermore, it provides an overview on a selection of specific procedures suitable for but not limited to behavioral screening in pharmacology and toxicology.

Scopolamine disrupts place navigation in rats and humans: a translational validation of the Hidden Goal Task in the Morris water maze and a real maze for humans

Czech Academy of Sciences Publication Activity Database

Laczó, J.; Marková, H.; Lobellová, Veronika; Gažová, I.; Pařízková, M.; Cerman, J.; Nekovářová, Tereza; Valeš, Karel; Klovrzová, S.; Harrison, J.; Windisch, M.; Vlček, Kamil; Svoboda, Jan; Hort, J.; Stuchlík, Aleš

2017-01-01

Roč. 234, č. 4 (2017), s. 535-547 ISSN 0033-3158 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA MŠk(CZ) LH14053 Institutional support: RVO:67985823 Keywords : spatial orientation * scopolamine * acetylcholinesterase inhibitor * human * rat Subject RIV: FH - Neurology OBOR OECD: Neurosciences (including psychophysiology Impact factor: 3.308, year: 2016

Effects of methimepip and JNJ-5207852 in Wistar rats exposed to an open-field with and without object and in Balb/c mice exposed to a radial-arm maze.

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Abuhamdah, Rushdie M A; van Rensburg, Ruan; Lethbridge, Natasha L; Ennaceur, Abdel; Chazot, Paul L

2012-01-01

The role of the histamine H(3) receptor (H(3)R) in anxiety is controversial, due to limitations in drug selectivity and limited validity of behavioral tests used in previous studies. In the present report, we describe two experiments. In the first one, Wistar rats were treated with an H(3)R agonist (methimepip), and exposed to an open-field. In the second one, Balb/c mice were treated with H(3)R agonist (methimepip) or antagonist (JNJ-5207852), and exposed to an open space 3D maze which is a modified version of the radial-arm maze. C57BL/6J saline treated mice were included for comparisons. When exposed to an empty open field, Wistar rats spent more time in the outer area and made very low number of brief crossings in the central area. However, when an object occupied the central area, rats crossed frequently into and spent a long time in the central area. Administration of a range of different doses of methimepip (selective H(3)R agonist) reduced the entries into the central area with a novel object, indicating enhanced avoidance response. In the 3D maze, both Balb/c and C57BL/6J saline-treated mice crossed frequently onto the bridges that radiate from the central platform but only C57BL/6J mice crossed onto the arms which extend the bridges. This suggests that Balb/c mice are more anxious than C57BL/6J mice. Neither methimepip nor JNJ-5207852 (selective H(3)R antagonist/inverse agonist) induced entry into the arms of the maze, indicative of lack of anxiolytic effects.

Age-dependent effect of high cholesterol diets on anxiety-like behavior in elevated plus maze test in rats

Science.gov (United States)

2014-01-01

Background Cholesterol is an essential component of brain and nerve cells and is essential for maintaining the function of the nervous system. Epidemiological studies showed that patients suffering from anxiety disorders have higher serum cholesterol levels. In this study, we investigated the influence of high cholesterol diet on anxiety-like behavior in elevated plus maze in animal model and explored the relationship between cholesterol and anxiety-like behavior from the aspect of central neurochemical changes. Methods Young (3 weeks old) and adult (20 weeks old) rats were given a high cholesterol diet for 8 weeks. The anxiety-like behavior in elevated plus maze test and changes of central neurochemical implicated in anxiety were measured. Results In young rats, high cholesterol diet induced anxiolytic-like behavior, decreased serum corticosterone (CORT), increased hippocampal brain-derived neurotrophic factor (BDNF), increased hippocampal mineralocorticoid receptor (MR) and decreased glucocorticoid receptor (GR). In adult rats, high cholesterol diet induced anxiety-like behavior and increase of serum CORT and decrease of hippocampal BDNF comparing with their respective control group that fed the regular diet. Discussion High cholesterol diet induced age-dependent effects on anxiety-like behavior and central neurochemical changes. High cholesterol diet might affect the central nervous system (CNS) function differently, and resulting in different behavior performance of anxiety in different age period. PMID:25179125

THE MEMORY SYSTEM ENGAGED DURING ACQUISITION DETERMINES THE EFFECTIVENESS OF DIFFERENT EXTINCTION PROTOCOLS

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Jarid eGoodman

2015-11-01

Full Text Available Previous research indicates that extinction of rodent maze behavior may occur without explicit performance of the previously required response. In latent extinction, confining an animal to a previously rewarded goal location without reinforcement is typically sufficient to produce extinction of maze learning. However, previous studies have not determined whether latent extinction may be successfully employed to extinguish all types of memory acquired in the maze, or whether only specific types of memory may be vulnerable to latent extinction. The present study examined whether latent extinction may be effective across two plus-maze tasks that depend on anatomically distinct neural systems. Adult male Long-Evans rats were trained in a hippocampus-dependent place learning task (experiment 1, in which animals were trained to approach a consistent spatial location for food reward. A separate group of rats were trained in a dorsolateral striatum-dependent response learning task (experiment 2, in which animals were trained to make a consistent egocentric body-turn response for food reward. Following training, animals received response extinction or latent extinction. For response extinction, animals were given the opportunity to execute the original running approach response toward the empty food cup. For latent extinction, animals were confined to the original goal locations with the empty food cup, thus preventing them from making the original running approach response. Results indicate that, relative to no extinction, latent extinction was effective at extinguishing memory in the place learning task, but remained ineffective in the response learning task. In contrast, typical response extinction remained very effective at extinguishing memory in both place and response learning tasks. The present findings confirm that extinction of maze learning may occur with or without overt performance of the previously acquired response, but that the

Effects of age on navigation strategy.

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Rodgers, M Kirk; Sindone, Joseph A; Moffat, Scott D

2012-01-01

Age differences in navigation strategies have been demonstrated in animals, with aged animals more likely to prefer an egocentric (route) strategy and younger animals more likely to prefer an allocentric (place) strategy. Using a novel virtual Y-maze strategy assessment (vYSA), the present study demonstrated substantial age differences in strategy preference in humans. Older adults overwhelmingly preferred an egocentric strategy, while younger adults were equally distributed between egocentric and allocentric preference. A preference for allocentric strategy on the Y-maze strategy assessment was found to benefit performance on an independent assessment (virtual Morris water task) only in younger adults. These results establish baseline age differences in spatial strategies and suggest this may impact performance on other spatial navigation assessments. The results are interpreted within the framework of age differences in hippocampal structure and function. Copyright © 2012 Elsevier Inc. All rights reserved.

The Tyrosine Phosphatase STEP Is Involved in Age-Related Memory Decline.

Science.gov (United States)

Castonguay, David; Dufort-Gervais, Julien; Ménard, Caroline; Chatterjee, Manavi; Quirion, Rémi; Bontempi, Bruno; Schneider, Jay S; Arnsten, Amy F T; Nairn, Angus C; Norris, Christopher M; Ferland, Guylaine; Bézard, Erwan; Gaudreau, Pierrette; Lombroso, Paul J; Brouillette, Jonathan

2018-04-02

Cognitive disabilities that occur with age represent a growing and expensive health problem. Age-associated memory deficits are observed across many species, but the underlying molecular mechanisms remain to be fully identified. Here, we report elevations in the levels and activity of the striatal-enriched phosphatase (STEP) in the hippocampus of aged memory-impaired mice and rats, in aged rhesus monkeys, and in people diagnosed with amnestic mild cognitive impairment (aMCI). The accumulation of STEP with aging is related to dysfunction of the ubiquitin-proteasome system that normally leads to the degradation of STEP. Higher level of active STEP is linked to enhanced dephosphorylation of its substrates GluN2B and ERK1/2, CREB inactivation, and a decrease in total levels of GluN2B and brain-derived neurotrophic factor (BDNF). These molecular events are reversed in aged STEP knockout and heterozygous mice, which perform similarly to young control mice in the Morris water maze (MWM) and Y-maze tasks. In addition, administration of the STEP inhibitor TC-2153 to old rats significantly improved performance in a delayed alternation T-maze memory task. In contrast, viral-mediated STEP overexpression in the hippocampus is sufficient to induce memory impairment in the MWM and Y-maze tests, and these cognitive deficits are reversed by STEP inhibition. In old LOU/C/Jall rats, a model of healthy aging with preserved memory capacities, levels of STEP and GluN2B are stable, and phosphorylation of GluN2B and ERK1/2 is unaltered. Altogether, these data suggest that elevated levels of STEP that appear with advancing age in several species contribute to the cognitive declines associated with aging. Copyright © 2018 Elsevier Ltd. All rights reserved.

Low-Dose Sevoflurane Promotes Hippocampal Neurogenesis and Facilitates the Development of Dentate Gyrus-Dependent Learning in Neonatal Rats

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Chong Chen

2015-04-01

Full Text Available 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.

The regulatory maze of quality control

International Nuclear Information System (INIS)

Stone, T.I.

1987-01-01

The appropriateness of specific procedures within a quality control program becomes difficult to assess when an attempt is made to collate all of the available information. This task is discussed from the perspective of the Joint Commission (JCAH Accreditation Manual), HHS(quality assurance program recommendations), equipment manufacturers maintenance schedules, and radiology administrative cost concerns

Dose-response effects of systemic anandamide administration in mice sequentially submitted to the open field and elevated plus-maze tests

OpenAIRE

Ribeiro,A.; Ferraz-de-Paula,V.; Pinheiro,M.L.; Palermo-Neto,J.

2009-01-01

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...

Neuronal activity in primate auditory cortex during the performance of audiovisual tasks.

Science.gov (United States)

Brosch, Michael; Selezneva, Elena; Scheich, Henning

2015-03-01

This study aimed at a deeper understanding of which cognitive and motivational aspects of tasks affect auditory cortical activity. To this end we trained two macaque monkeys to perform two different tasks on the same audiovisual stimulus and to do this with two different sizes of water rewards. The monkeys had to touch a bar after a tone had been turned on together with an LED, and to hold the bar until either the tone (auditory task) or the LED (visual task) was turned off. In 399 multiunits recorded from core fields of auditory cortex we confirmed that during task engagement neurons responded to auditory and non-auditory stimuli that were task-relevant, such as light and water. We also confirmed that firing rates slowly increased or decreased for several seconds during various phases of the tasks. Responses to non-auditory stimuli and slow firing changes were observed during both the auditory and the visual task, with some differences between them. There was also a weak task-dependent modulation of the responses to auditory stimuli. In contrast to these cognitive aspects, motivational aspects of the tasks were not reflected in the firing, except during delivery of the water reward. In conclusion, the present study supports our previous proposal that there are two response types in the auditory cortex that represent the timing and the type of auditory and non-auditory elements of a auditory tasks as well the association between elements. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Preserved learning and memory following 5-fluorouracil and cyclophosphamide treatment in rats.

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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.

A genetic algorithm for optimization of neural network capable of learning to search for food in a maze

Science.gov (United States)

Budilova, E. V.; Terekhin, A. T.; Chepurnov, S. A.

1994-09-01

A hypothetical neural scheme is proposed that ensures efficient decision making by an animal searching for food in a maze. Only the general structure of the network is fixed; its quantitative characteristics are found by numerical optimization that simulates the process of natural selection. Selection is aimed at maximization of the expected number of descendants, which is directly related to the energy stored during the reproductive cycle. The main parameters to be optimized are the increments of the interneuronal links and the working-memory constants.

Emotional instability but intact spatial cognition in adenosine receptor 1 knock out mice.

Science.gov (United States)

Lang, Undine E; Lang, Florian; Richter, Kerstin; Vallon, Volker; Lipp, Hans-Peter; Schnermann, Jürgen; Wolfer, David P

2003-10-17

Several lines of evidence point to the involvement of adenosine in the regulation of important central mechanisms such as cognition, arousal, aggression and anxiety. In order to elucidate the involvement of the adenosine A1 receptor (A1AR) in spatial learning and the control of exploratory behaviour, we assessed A1AR knockout mice (A1AR-/-) and their wild-type littermates (A1AR+/+) in a place navigation task in the water maze and in a battery of forced and free exploration tests. In the water maze, A1AR-/- mice showed normal escape latencies and were indistinguishable from controls with respect to measures of spatial performance during both training and probe trial. But despite normal performance they showed increased wall hugging, most prominently after the relocation of the goal platform for reversal training. Quantitative analysis of strategy choices indicated that wall hugging was increased mainly at the expense of chaining and passive floating, whereas the frequency of trials characterised as direct swims or focal searching was normal in A1AR-/- mice. These results indicate intact spatial cognition, but mildly altered emotional reactions to the water maze environment. In line with this interpretation, A1AR-/- mice showed normal levels and patterns of activity, but a mild increase of some measures of anxiety in our battery of forced and free exploration paradigms. These results are in line with findings published using a genetically similar line, but demonstrate that the magnitude of the changes and the range of affected behavioural measures may vary considerably depending on the environmental conditions during testing.

SSP-002392, a new 5-HT4 receptor agonist, dose-dependently reverses scopolamine-induced learning and memory impairments in C57Bl/6 mice.

Science.gov (United States)

Lo, Adrian C; De Maeyer, Joris H; Vermaercke, Ben; Callaerts-Vegh, Zsuzsanna; Schuurkes, Jan A J; D'Hooge, Rudi

2014-10-01

5-HT4 receptors (5-HT4R) are suggested to affect learning and memory processes. Earlier studies have shown that animals treated with 5-HT4R agonists, often with limited selectivity, show improved learning and memory with retention memory often being assessed immediately after or within 24 h after the last training session. In this study, we characterized the effect of pre-training treatment with the selective 5-HT4R agonist SSP-002392 on memory acquisition and the associated long-term memory retrieval in animal models of impaired cognition. Pre-training treatment with SSP-002392 (0.3 mg/kg, 1.5 mg/kg and 7.5 mg/kg p.o.) dose-dependently inhibited the cognitive deficits induced by scopolamine (0.5 mg/kg s.c.) in two different behavioral tasks: passive avoidance and Morris water maze. In the Morris water maze, spatial learning was significantly improved after treatment with SSP-002392 translating in an accelerated and more efficient localization of the hidden platform compared to scopolamine-treated controls. Moreover, retention memory was assessed 24 h (passive avoidance) and 72 h (Morris water maze) after the last training session of cognitive-impaired animals and this was significantly improved in animals treated with SSP-002392 prior to the training sessions. Furthermore, the effects of SSP-002392 were comparable to galanthamine hydrobromide. We conclude that SSP-002392 has potential as a memory-enhancing compound. Copyright © 2014 Elsevier Ltd. All rights reserved.

Glucose Injections into the Dorsal Hippocampus or Dorsolateral Striatum of Rats Prior to T-Maze Training: Modulation of Learning Rates and Strategy Selection

Science.gov (United States)

Canal, Clinton E.; Stutz, Sonja J.; Gold, Paul E.

2005-01-01

The present experiments examined the effects of injecting glucose into the dorsal hippocampus or dorsolateral striatum on learning rates and on strategy selection in rats trained on a T-maze that can be solved by using either a hippocampus-sensitive place or striatum-sensitive response strategy. Percentage strategy selection on a probe trial…

Anxiety-like behavior as an early endophenotype in the TgF344-AD rat model of Alzheimer's disease.

Science.gov (United States)

Pentkowski, Nathan S; Berkowitz, Laura E; Thompson, Shannon M; Drake, Emma N; Olguin, Carlos R; Clark, Benjamin J

2018-01-01

Alzheimer's disease (AD) is characterized by progressive cognitive decline and the presence of aggregates of amyloid beta (plaques) and hyperphosphorylated tau (tangles). Early diagnosis through neuropsychological testing is difficult due to comorbidity of symptoms between AD and other types of dementia. As a result, there is a need to identify the range of behavioral phenotypes expressed in AD. In the present study, we utilized a transgenic rat (TgF344-AD) model that bears the mutated amyloid precursor protein as well as presenilin-1 genes, resulting in progressive plaque and tangle pathogenesis throughout the cortex. We tested young adult male and female TgF344-AD rats in a spatial memory task in the Morris water maze and for anxiety-like behavior in the elevated plus-maze. Results indicated that regardless of sex, TgF344-AD rats exhibited increased anxiety-like behavior in the elevated plus-maze, which occurred without significant deficits in the spatial memory. Together, these results indicate that enhanced anxiety-like behavior represents an early-stage behavioral marker in the TgF344-AD rat model. Copyright © 2017 Elsevier Inc. All rights reserved.

Protective effects of pseudoginsenoside-F11 on methamphetamine-induced neurotoxicity in mice.

Science.gov (United States)

Wu, Chun Fu; Liu, Yan Li; Song, Ming; Liu, Wen; Wang, Jin Hui; Li, Xian; Yang, Jing Yu

2003-08-01

In the present study, pseudoginsenoside-F(11) (PF(11)), a saponin that existed in American ginseng, was studied on its protective effect on methamphetamine (MA)-induced behavioral and neurochemical toxicities in mice. MA was intraperitoneally administered at the dose of 10 mg/kg four times at 2-h intervals, and PF(11) was orally administered at the doses of 4 and 8 mg/kg two times at 4-h intervals, 60 min prior to MA administration. The results showed that PF(11) did not significantly influence, but greatly ameliorated, the anxiety-like behavior induced by MA in the light-dark box task. In the forced swimming task, PF(11) significantly shortened the prolonged immobility time induced by MA. In the appetitively motivated T-maze task, PF(11) greatly shortened MA-induced prolonged latency and decreased the error counts. Similar results were also observed in the Morris water maze task. PF(11) significantly shortened the escape latency prolonged by MA. There were significant decreases in the contents of dopamine (DA), 3,4-dihydroxyphenacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoacetic acid (5-HIAA) in the brain of MA-treated mice. PF(11) could partially, but significantly, antagonize MA-induced decreases of DA. The above results demonstrate that PF(11) is effective in protection of MA-induced neurotoxicity and also suggest that natural products, such as ginseng, might be potential candidates for the prevention and treatment of the neurological disorders induced by MA abuse.

A novel elevated plus-maze procedure to avoid the one-trial tolerance problem

Directory of Open Access Journals (Sweden)

Peggy eSchneider

2011-07-01

Full Text Available The elevated plus-maze (EPM test is one of the most commonly used behavioural assays to evaluate anxiety-related behaviour in rodents. It is a rather economic test which usually uses a short (5 min protocol and does not require conditioning of the animals. The critical measure for anxiety is the time spent in the open arms of the maze. A confounding problem of the EPM is the so called one-trial tolerance (OTT, characterised by a marked decrease of open arm exploration in spite of treatment with anxiolytic acting benzodiazepines upon re-exposure to the EPM. This consistent finding is often raised as an evidence for the inappropriateness to re-test rodents in the EPM. However, a reliable re-test paradigm would broaden the usability and effectiveness of this test.Therefore, we tested how a prolongation of the inter-trial interval to 28 days (instead of the usual 24 hours, and an additional change of the testing room would affect the open arm time and other behaviours on the EPM. In two experiments, drug naive Wistar rats were exposed to the EPM on trial 1, and treated intraperitoneally with either vehicle or midazolam (0.25 mg/kg 30 min before trial 2. Then, trial 2 (28 days after trial 1 was carried out in either the same testing room (Exp. 1 or a second unfamiliar room (Exp. 2.Twenty-eight days after trial 1 the open arm time of the rats in the vehicle treated control rats of both experimental groups was comparable to that of the first trial, independent of the testing room. Most importantly, we found that the treatment with the benzodiazepine midazolam had a significantly anxiolytic-like (i.e. increase of open arm time effect in trial 2 only when conducted in the previously unfamiliar testing room (Exp. 2. We suggest that in order to reliably re-test the EPM and to prevent confounding effects due to the OTT, an inter-trial interval of 28 days and a change in testing rooms reinstates anxiolytic-like actions of benzodiazepines

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

Performance of Male and Female C57BL/6J Mice on Motor and Cognitive Tasks Commonly Used in Pre-Clinical Traumatic Brain Injury Research

Science.gov (United States)

Tucker, Laura B.; Fu, Amanda H.

2016-01-01

Abstract To date, clinical trials have failed to find an effective therapy for victims of traumatic brain injury (TBI) who live with motor, cognitive, and psychiatric complaints. Pre-clinical investigators are now encouraged to include male and female subjects in all translational research, which is of particular interest in the field of neurotrauma given that circulating female hormones (progesterone and estrogen) have been demonstrated to exert neuroprotective effects. To determine whether behavior of male and female C57BL6/J mice is differentially impaired by TBI, male and cycling female mice were injured by controlled cortical impact and tested for several weeks with functional assessments commonly employed in pre-clinical research. We found that cognitive and motor impairments post-TBI, as measured by the Morris water maze (MWM) and rotarod, respectively, were largely equivalent in male and female animals. However, spatial working memory, assessed by the y-maze, was poorer in female mice. Female mice were generally more active, as evidenced by greater distance traveled in the first exposure to the open field, greater distance in the y-maze, and faster swimming speeds in the MWM. Statistical analysis showed that variability in all behavioral data was no greater in cycling female mice than it was in male mice. These data all suggest that with careful selection of tests, procedures, and measurements, both sexes can be included in translational TBI research without concern for effect of hormones on functional impairments or behavioral variability. PMID:25951234

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.

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.

Progressive impairment of directional and spatially precise trajectories by TgF344-AD Rats in the Morris Water Task

OpenAIRE

Thompson, Shannon; Harvey, Ryan; Clark, Benjamin; Drake, Emma; Berkowitz, Laura

2018-01-01

Spatial navigation is impaired in early stages of Alzheimers disease (AD), and may be a defining behavioral marker of preclinical AD. Nevertheless, limitations of diagnostic criteria for AD and within animal models of AD make characterization of preclinical AD difficult. A new rat model (TgF344-AD) of AD overcomes many of these limitations, though spatial navigation has not been comprehensively assessed. Using the hidden and cued platform variants of the Morris water task, a longitudinal asse...

Effect of a Hypocretin/Orexin Antagonist on Neurocognitive Performance

Science.gov (United States)

2015-11-01

release in freely-moving rat. Location: Hall A-C Presentation time: Tuesday , Nov 15, 2011, 1:00 PM - 2:00 PM Authors: *J. VAZQUEZ, A. NGUYEN, T. KILDUFF...induces sleep in rats but does not impair spatial reference memory performance during wake Location: Hall A-C Presentation time: Tuesday , Nov 15, 2011, 2...of a platform in a spatial reference memory task ( Morris Water Maze). Next day, they were dosed with either ALM (100 mg/kg i.p.), ZOL (30 mg/kg i.p

Water hammer

International Nuclear Information System (INIS)

Anon.

1979-01-01

The overall NRC program for the resolution of the water hammer issue is divided into four tasks: water hammer summary reports; revision of CP and OL review procedures; water hammer positions for operating reactors; and water hammer safety studies

Water management - management actions applied to water resources system

International Nuclear Information System (INIS)

Petkovski, Ljupcho; Tanchev, Ljubomir

2001-01-01

In this paper are presented a general description of water resource systems, a systematisation of the management tasks and the approaches for solution, including a review of methods used for solution of water management tasks and the fundamental postulates in the management. The management of water resources is a synonym for the management actions applied to water resource systems. It is a general term that unites planning and exploitation of the systems. The modern planning assumes separating the water racecourse part from the hydro technical part of the project. The water resource study is concerned with the solution for the resource problem. This means the parameters of the system are determined in parallel with the definition of the water utilisation regime. The hydro-technical part of the project is the design of structures necessary for the water resource solution. (Original)

Nuclear power plant control room task analysis. Pilot study for pressurized water reactors

International Nuclear Information System (INIS)

Barks, D.B.; Kozinsky, E.J.; Eckel, S.

1982-05-01

The purposes of this nuclear plant task analysis pilot study: to demonstrate the use of task analysis techniques on selected abnormal or emergency operation events in a nuclear power plant; to evaluate the use of simulator data obtained from an automated Performance Measurement System to supplement and validate data obtained by traditional task analysis methods; and to demonstrate sample applications of task analysis data to address questions pertinent to nuclear power plant operational safety: control room layout, staffing and training requirements, operating procedures, interpersonal communications, and job performance aids. Five data sources were investigated to provide information for a task analysis. These sources were (1) written operating procedures (event-based); (2) interviews with subject matter experts (the control room operators); (3) videotapes of the control room operators (senior reactor operators and reactor operators) while responding to each event in a simulator; (4) walk-/talk-throughs conducted by control room operators for each event; and (5) simulator data from the PMS

An elevated plus-maze in mixed reality for studying human anxiety-related behavior.

Science.gov (United States)

Biedermann, Sarah V; Biedermann, Daniel G; Wenzlaff, Frederike; Kurjak, Tim; Nouri, Sawis; Auer, Matthias K; Wiedemann, Klaus; Briken, Peer; Haaker, Jan; Lonsdorf, Tina B; Fuss, Johannes

2017-12-21

A dearth of laboratory tests to study actual human approach-avoidance behavior has complicated translational research on anxiety. The elevated plus-maze (EPM) is the gold standard to assess approach-avoidance behavior in rodents. Here, we translated the EPM to humans using mixed reality through a combination of virtual and real-world elements. In two validation studies, we observed participants' anxiety on a behavioral, physiological, and subjective level. Participants reported higher anxiety on open arms, avoided open arms, and showed an activation of endogenous stress systems. Participants' with high anxiety exhibited higher avoidance. Moreover, open arm avoidance was moderately predicted by participants' acrophobia and sensation seeking, with opposing influences. In a randomized, double blind, placebo controlled experiment, GABAergic stimulation decreased avoidance of open arms while alpha-2-adrenergic antagonism increased avoidance. These findings demonstrate cross-species validity of open arm avoidance as a translational measure of anxiety. We thus introduce the first ecologically valid assay to track actual human approach-avoidance behavior under laboratory conditions.

Sustainable development of water resources, water supply and environmental sanitation.

CSIR Research Space (South Africa)

Austin, LM

2006-01-01

Full Text Available and be capable of destroying or isolating pathogens. A need exists for documentary evidence to support various claims about different storage periods for ensuring pathogen die-off and safe handling of biosolids (Peasy 2000). Handling of faecal material... in Water and Environmental Health, Task no. 324. [Online] http://www/lboro.ac.uk/well/resources/well-studies/full-reports-pdf/task0324.pdf WHO (2001). Water quality, guidelines, standards and health: Assessment of risk and risk management for water...

Separating defence and civilian radioactive waste programs in Nevada: can the public navigate the maze?

International Nuclear Information System (INIS)

Nielsen, R.A.

1999-01-01

Nevada is at the centre of public policy debate with regards to high and low level radioactive waste disposal. Nevada's Yucca Mountain is the only site under consideration for a US geologic repository for commercial spent nuclear fuel and defence high level waste. The Nevada Test Site (NTS) has long been a low level waste (LLW) disposal facility for the Department of Energy (DOE) defence waste and is now expected to take even more LLW as the preferred site for a regional or centralised disposal facility. Furthermore, the primary mission at NTS, defence, continues to add more contamination to the site. Combined, these facts present a public policy enigma, confused further by the intentional separation of the programs by DOE, even though all are essentially conducted at the same site. Involving the public in policy decisions for these programs is a dilemma because the public does not make the same artificial distinctions between them as DOE, DOE credibility suffers from past public involvement efforts conducted during an era of Cold War secrecy and because DOE public involvement programs are operated independently, with little or no co-operation between programs. The public does not know where it fits into the DOE decision-making process or if it impacts the policy decisions being made that affect it. This paper examines the complex maze of radioactive policy and bureaucracy in order to unveil the enigma Nevada residents face. Are they able to navigate this maze to effectively participate in government policy and decision-making? Or, will they remain confused by the government bureaucracy which deliberately makes a mess of the situation and seeks to exploit a politically weak state with large tracts of federally controlled land? lt further evaluates the effect this enigma has in producing acceptable public policy for radioactive waste disposal in the US, the role of public participation in that policy, and the reason the public is disillusioned and disengaged in the

Effects of age on spatial information processing: relationship to senescent changes in brain noradrenergic and opioid systems

International Nuclear Information System (INIS)

Rapp, P.R.

1985-01-01

A major focus in current research on aging is the identification of senescent changes in cognitive function in laboratory animals. This literature indicates that the processing of spatial information may be particularly impaired during senescence. The degree to which nonspecific factors (eg. sensory of motor deficits) contribute to behavioral impairments in aging, however, remains largely uninvestigated. In addition, few studies have attempted to identify senescent changes in brain structure and function which might underlie the behavioral manifestations of aging. In the behavioral experiments reported here, the authors tested young, middle-age, and senescent rates in several versions of a spatial memory task, the Morris water maze. The results of these investigations demonstrate that aged rats are significantly impaired in the Morris task compared to young or middle-age animals. In addition, these studies indicate that age-related deficits in the water maze reflect a specific dysfunction in the ability of older animals to effectively process spatial information rather than a senescent decline in sensory or motor functions. Using the subjects from the behavioral studies, additional investigations assessed whether age-dependent changes in neurochemical and neuroanatomical systems which are known to mediate spatial learning in young animals were related to the behavioral deficits exhibited by aged rats. The results of these studies demonstrate that a portion of senescent animals exhibit significant increases in lateral septal 3 H-desmethylimipramine binding and decrease in 3 H-naloxone binding in this same region as assessed by quantitative in vitro autoradiography

Engineering Task Plan for Water Supply for Spray Washers on the Support Trucks

International Nuclear Information System (INIS)

BOGER, R.M.

2000-01-01

This Engineering Task Plan (ETP) defines the task and deliverables associated with the design, fabrication and testing of an improved spray wash system for the Rotary Mode Core Sampling (RMCS) System Support Trucks

Behavioral effects of diazepam in the murine plus-maze: flumazenil antagonism of enhanced head dipping but not the disinhibition of open-arm avoidance.

Science.gov (United States)

Dalvi, A; Rodgers, R J

1999-04-01

Although it is widely believed that benzodiazepines reduce anxiety through positive allosteric modulation of the GABA(A)-chloride channel complex, this is not the only mechanism through which agents of this class can modify CNS function. Furthermore, a significant number of reports of apparent flumazenil blockade of diazepam anxiolysis in animal models have paid limited attention to possible intrinsic behavioral actions of the antagonist per se. In the present study, ethological methods were employed to assess in detail the effects of diazepam, flumazenil, and their combination on the behavior of male DBA/2 mice in the elevated plus-maze paradigm. In two experiments, diazepam (1.5 mg/kg) alone reduced open-arm avoidance and increased head dipping, whereas flumazenil (10-40 mg/kg) alone was without significant behavioral effect. However, with the sole exception of head dipping, prior administration of flumazenil (10 and 40 mg/kg) failed to block the behavioral effects of diazepam under present test conditions. These findings imply that the anxiolytic effects of diazepam in the mouse plus-maze are not mediated through flumazenil-sensitive benzodiazepine receptors and that alternate mechanisms must be considered.

Long-lasting effects of maternal separation on an animal model of post-traumatic stress disorder: effects on memory and hippocampal oxidative stress.

Science.gov (United States)

Diehl, Luisa A; Alvares, Lucas O; Noschang, Cristie; Engelke, Douglas; Andreazza, Ana C; Gonçalves, Carlos Alberto S; Quillfeldt, Jorge A; Dalmaz, Carla

2012-04-01

Adverse early life events, such as periodic maternal separation, may alter the normal pattern of brain development and subsequently the vulnerability to a variety of mental disorders in adulthood. Patients with a history of early adversities show higher frequency of post-traumatic stress disorder (PTSD). This study was undertaken to verify if repeated long-term separation of pups from dams would affect memory and oxidative stress parameters after exposure to an animal model of PTSD. Nests of Wistar rats were divided into intact and subjected to maternal separation (incubator at 32°C, 3 h/day) during post-natal days 1-10. When adults, the animals were subdivided into exposed or not to a PTSD model consisting of exposure to inescapable footshock, followed by situational reminders. One month after exposure to the shock, the animals were exposed to a memory task (Morris water maze) and another month later animals were sacrificed and DNA breaks and antioxidant enzymes activities were measured in the hippocampus. Rats exposed to shock or maternal separation plus shock showed long-lasting effects on spatial memory, spending more time in the opposite quadrant of the water maze. This effect was higher in animals subjected to both maternal separation and shock. Both shock and maternal separation induced a higher score of DNA breaks in the hippocampus. No differences were observed on antioxidant enzymes activities. In conclusion, periodic maternal separation may increase the susceptibility to the effects of a stressor applied in adulthood on performance in the water maze. Increased DNA breaks in hippocampus was induced by both, maternal separation and exposure to shock.

Water and Energy Sustainability: A Balance of Government Action and Industry Innovation

Energy Technology Data Exchange (ETDEWEB)

Ben Grunewald

2009-12-31

By completing the tasks and subtasks of the project, the Ground Water Protection Council (GWPC) through its state regulatory agency members and oil and gas industry partners, will bring attention to water quality and quantity issues and make progress toward water and energy sustainability though enhanced water protection and conservation thus enhancing the viability of the domestic fossil fuel industry. The project contains 4 major independent Tasks. Task 1 - Work Plan: Water-Energy Sustainability: A Symposium on Resource Viability. Task 2 - Work Plan: A Regional Assessment of Water and Energy Sustainability. Task 3 - Work Plan: Risk Based Data Management System-Water Water and Energy Module. Task 4 - Work Plan: Identification and Assessment of States Regulatory Programs Regarding Geothermal Heating and Cooling Systems. Each task has a specific scope (details given).

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. © The Author(s) 2015.

Music exposure improves spatial cognition by enhancing the BDNF level of dorsal hippocampal subregions in the developing rats.

Science.gov (United States)

Xing, Yingshou; Chen, Wenxi; Wang, Yanran; Jing, Wei; Gao, Shan; Guo, Daqing; Xia, Yang; Yao, Dezhong

2016-03-01

Previous research has shown that dorsal hippocampus plays an important role in spatial memory process. Music exposure can enhance brain-derived neurotrophic factor (BDNF) expression level in dorsal hippocampus (DH) and thus enhance spatial cognition ability. But whether music experience may affect different subregions of DH in the same degree remains unclear. Here, we studied the effects of exposure to Mozart K.448 on learning behavior in developing rats using the classical Morris water maze task. The results showed that early music exposure could enhance significantly learning performance of the rats in the water maze test. Meanwhile, the BDNF/TrkB level of dorsal hippocampus CA3 (dCA3) and dentate gyrus (dDG) was significantly enhanced in rats exposed to Mozart music as compared to those without music exposure. In contrast, the BDNF/TrkB level of dorsal hippocampus CA1 (dCA1) was not affected. The results suggest that the spatial memory improvement by music exposure in rats may be associated with the enhanced BDNF/TrkB level of dCA3 and dDG. Copyright © 2016 Elsevier Inc. All rights reserved.

Spatial learning and memory is preserved in rats after early development in a microgravity environment

Science.gov (United States)

Temple, Meredith D.; Kosik, Kenneth S.; Steward, Oswald

2002-01-01

This study evaluated the cognitive mapping abilities of rats that spent part of their early development in a microgravity environment. Litters of male and female Sprague-Dawley rat pups were launched into space aboard the National Aeronautics and Space Administration space shuttle Columbia on postnatal day 8 or 14 and remained in space for 16 days. These animals were designated as FLT groups. Two age-matched control groups remained on Earth: those in standard vivarium housing (VIV) and those in housing identical to that aboard the shuttle (AGC). On return to Earth, animals were tested in three different tasks that measure spatial learning ability, the Morris water maze (MWM), and a modified version of the radial arm maze (RAM). Animals were also tested in an open field apparatus to measure general activity and exploratory activity. Performance and search strategies were evaluated in each of these tasks using an automated tracking system. Despite the dramatic differences in early experience, there were remarkably few differences between the FLT groups and their Earth-bound controls in these tasks. FLT animals learned the MWM and RAM as quickly as did controls. Evaluation of search patterns suggested subtle differences in patterns of exploration and in the strategies used to solve the tasks during the first few days of testing, but these differences normalized rapidly. Together, these data suggest that development in an environment without gravity has minimal long-term impact on spatial learning and memory abilities. Any differences due to development in microgravity are quickly reversed after return to earth normal gravity.

Hippocampus, delay discounting, and vicarious trial-and-error.

Science.gov (United States)

Bett, David; Murdoch, Lauren H; Wood, Emma R; Dudchenko, Paul A

2015-05-01

In decision-making, an immediate reward is usually preferred to a delayed reward, even if the latter is larger. We tested whether the hippocampus is necessary for this form of temporal discounting, and for vicarious trial-and-error at the decision point. Rats were trained on a recently developed, adjustable delay-discounting task (Papale et al. (2012) Cogn Affect Behav Neurosci 12:513-526), which featured a choice between a small, nearly immediate reward, and a larger, delayed reward. Rats then received either hippocampus or sham lesions. Animals with hippocampus lesions adjusted the delay for the larger reward to a level similar to that of sham-lesioned animals, suggesting a similar valuation capacity. However, the hippocampus lesion group spent significantly longer investigating the small and large rewards in the first part of the sessions, and were less sensitive to changes in the amount of reward in the large reward maze arm. Both sham- and hippocampus-lesioned rats showed a greater amount of vicarious trial-and-error on trials in which the delay was adjusted. In a nonadjusting version of the delay discounting task, animals with hippocampus lesions showed more variability in their preference for a larger reward that was delayed by 10 s compared with sham-lesioned animals. To verify the lesion behaviorally, rat were subsequently trained on a water maze task, and rats with hippocampus lesions were significantly impaired compared with sham-lesioned animals. The findings on the delay discounting tasks suggest that damage to the hippocampus may impair the detection of reward magnitude. © 2014 Wiley Periodicals, Inc.

MGlu5 antagonism impairs exploration and memory of spatial and non-spatial stimuli in rats

DEFF Research Database (Denmark)

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

2008-01-01

and it was found that: 1) Locomotion during exploration of spatial environments and exploration time at novel objects were reduced by i.p. but not by prelimbic administration of MPEP, 2) spatial short-term memory was impaired in cross-maze and object discrimination was reduced after both types of administration, 3......) long-term retention of spatial conditioning in the cross-maze was inhibited after i.p. applications which 4) also inhibited spontaneous alternation performance during maze-exploration. Reduced exploratory locomotion and exploration time after i.p. injections may have contributed to the observed......Metabotropic glutamate receptor subtype 5 (mGlu5) has been implicated in memory processing in some but not all learning tasks.  The reason why this receptor is involved in some tasks but not in others remains to be determined.  The present experiments using rats examined effects of the mGlu5...

An open-source toolbox for automated phenotyping of mice in behavioral tasks

Directory of Open Access Journals (Sweden)

Tapan P Patel

2014-10-01

Full Text Available Classifying behavior patterns in mouse models of neurological, psychiatric and neurodevelopmental disorders is critical for understanding disease causality and treatment. However, complete characterization of behavior is time-intensive, prone to subjective scoring, and often requires specialized equipment. Although several reports describe automated home-cage monitoring and individual task scoring methods, we report the first open source, comprehensive toolbox for automating the scoring of several common behavior tasks used by the neuroscience community. We show this new toolbox is robust and achieves equal or better consistency when compared to manual scoring methods. We use this toolbox to study the alterations in behavior that occur following blast-induced traumatic brain injury (bTBI, and study if these behavior patterns are altered following genetic deletion of the transcription factor Ets-like kinase 1 (Elk-1. Due to the role of Elk-1 in neuronal survival and proposed role in synaptic plasticity, we hypothesized that Elk-1 deletion would improve some neurobehavioral deficits, while impairing others, following blast exposure. In Elk-1 knockout animals, deficits in open field, spatial object recognition and elevated zero maze performance after blast exposure disappeared, while new significant deficits appeared in spatial and associative memory. These are the first data suggesting a molecular mediator of anxiety deficits following blast-induced traumatic brain injury, and represent the utility of the broad screening tool we developed. More broadly, we envision this open-source toolbox will provide a more consistent and rapid analysis of behavior across many neurological diseases, promoting the rapid discovery of novel pathways mediating disease progression and treatment.

A low-cost touchscreen operant chamber using a Raspberry Pi™.

Science.gov (United States)

O'Leary, James D; O'Leary, Olivia F; Cryan, John F; Nolan, Yvonne M

2018-03-08

The development of a touchscreen platform for rodent testing has allowed new methods for cognitive testing that have been back-translated from clinical assessment tools to preclinical animal models. This platform for cognitive assessment in animals is comparable to human neuropsychological tests such as those employed by the Cambridge Neuropsychological Test Automated Battery, and thus has several advantages compared to the standard maze apparatuses typically employed in rodent behavioral testing, such as the Morris water maze. These include improved translation of preclinical models, as well as high throughput and the automation of animal testing. However, these systems are relatively expensive, which can impede progress for researchers with limited resources. Here we describe a low-cost touchscreen operant chamber based on the single-board computer, Raspberry Pi TM , which is capable of performing tasks similar to those supported by current state-of-the-art systems. This system provides an affordable alternative for cognitive testing in a touchscreen operant paradigm for researchers with limited funding.

DPP6 Loss Impacts Hippocampal Synaptic Development and Induces Behavioral Impairments in Recognition, Learning and Memory

Directory of Open Access Journals (Sweden)

Lin Lin

2018-03-01

Full Text Available DPP6 is well known as an auxiliary subunit of Kv4-containing, A-type K+ channels which regulate dendritic excitability in hippocampal CA1 pyramidal neurons. We have recently reported, however, a novel role for DPP6 in regulating dendritic filopodia formation and stability, affecting synaptic development and function. These results are notable considering recent clinical findings associating DPP6 with neurodevelopmental and intellectual disorders. Here we assessed the behavioral consequences of DPP6 loss. We found that DPP6 knockout (DPP6-KO mice are impaired in hippocampus-dependent learning and memory. Results from the Morris water maze and T-maze tasks showed that DPP6-KO mice exhibit slower learning and reduced memory performance. DPP6 mouse brain weight is reduced throughout development compared with WT, and in vitro imaging results indicated that DPP6 loss affects synaptic structure and motility. Taken together, these results show impaired synaptic development along with spatial learning and memory deficiencies in DPP6-KO mice.

Behavioral Neuroscience Laboratory

Data.gov (United States)

Federal Laboratory Consortium — This lab supports cognitive research using rodent models. Capabilities for behavioral assessments include:Morris water maze and Barnes maze (spatial memory)elevate...

Optimized training of responsible shift personnel in nuclear power plants. Supplement volume 3 for chapter 5: Task analysis

International Nuclear Information System (INIS)

1985-01-01

Derivation of learning targets from task analyses requires consideration of all process steps relevant to safety. This supplement volume indicates the functions they serve, classes of tasks, list of tasks, an example of task solution, the class of tasks 'abnormal operation' (heavy water reator), the definition of learning stages, the list of verbs for relating learning to stages, descriptors for technical and abnormal operation (heavy water reactor), verification of descriptors, and connection of action and learning targets by descriptors. (DG) [de

Similarities and differences between the brain networks underlying allocentric and egocentric spatial learning in rat revealed by cytochrome oxidase histochemistry.

Science.gov (United States)

Rubio, S; Begega, A; Méndez, M; Méndez-López, M; Arias, J L

2012-10-25

The involvement of different brain regions in place- and response-learning was examined using a water cross-maze. Rats were trained to find the goal from the initial arm by turning left at the choice point (egocentric strategy) or by using environmental cues (allocentric strategy). Although different strategies were required, the same maze and learning conditions were used. Using cytochrome oxidase histochemistry as a marker of cellular activity, the function of the 13 diverse cortical and subcortical regions was assessed in rats performing these two tasks. Our results show that allocentric learning depends on the recruitment of a large functional network, which includes the hippocampal CA3, dentate gyrus, medial mammillary nucleus and supramammillary nucleus. Along with the striatum, these last three structures are also related to egocentric spatial learning. The present study provides evidence for the contribution of these regions to spatial navigation and supports a possible functional interaction between the two memory systems, as their structural convergence may facilitate functional cooperation in the behaviours guided by more than one strategy. In summary, it can be argued that spatial learning is based on dynamic functional systems in which the interaction of brain regions is modulated by task requirements. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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

2017-11-01

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

Vicarious trial-and-error behavior and hippocampal cytochrome oxidase activity during Y-maze discrimination learning in the rat.

Science.gov (United States)

Hu, Dan; Xu, Xiaojuan; Gonzalez-Lima, Francisco

2006-03-01

The present study investigated whether more vicarious trial-and-error (VTE) behavior, defined by head movement from one stimulus to another at a choice point during simultaneous discriminations, led to better visual discrimination learning in a Y-maze, and whether VTE behavior was a function of the hippocampus by measuring regional brain cytochrome oxidase (C.O.) activity, an index of neuronal metabolic activity. The results showed that the more VTEs a rat made, the better the rat learned the visual discrimination. Furthermore, both learning and VTE behavior during learning were correlated to C.O. activity in the hippocampus, suggesting that the hippocampus plays a role in VTE behavior during discrimination learning.

Effects of chronic administration of fenproporex on cognitive and non-cognitive behaviors.

Science.gov (United States)

Gonçalves, Cinara L; Furlanetto, Camila B; Valvassori, Samira S; Bavaresco, Daniela V; Varela, Roger B; Budni, Josiane; Quevedo, João; Streck, Emilio L

2015-04-01

Fenproporex (Fen) is an amphetamine-based anorectic; amphetamine use causes a broad range of severe cognitive deficits and anxiogenic-like effects. In this study we evaluated pharmacological effects of the chronic administration of Fen on cognitive and non-cognitive behaviors. Male adult Wistar rats received intraperitoneal administration of vehicle (control group) or Fen (6.25, 12.5 or 25 mg/kg) for 14 days; the animals were then subjected to habituation and object recognition tasks in open-field apparatus, and elevated plus-maze task. The administration of Fen (12.5 and 25 mg/kg) impaired habituation during the second exposure to the habituation task. In addition, the same doses of Fen also impaired the performance in object recognition task. In elevated plus-maze task, the administration of Fen (in all doses tested) induced anxiogenic-like effects in rats. Our results suggest that chronic Fen administration alters memory and induces anxiogenic-like effects in rats.

Multiobjective decision-making in integrated water management

NARCIS (Netherlands)

Wind, H.G.; Pouwels, I.H.M.; Pouwels, I.H.M.; Witter, V.J.

1995-01-01

Traditionally, decision-making by water authorities in the Netherlands is largely based on intuition. Their tasks were, after all, relatively few and straight-forward. The growing number of tasks, together with the new integrated approach on water management issues, however, induces water

The role of physical content in piagetian spatial tasks: Sex differences in spatial knowledge?

Science.gov (United States)

Golbeck, Susan L.

Sex-related differences on Piagetian horizontality (water level) and verticality (plumb line) tasks were examined in 64 college students. It was hypothesized that females' difficulties on these Euclidean spatial problems are due not to differences in underlying spatial competence, but rather to differences in knowledge of task specific information about the physical properties of water levels and plumb lines. This was tested by presenting subjects with the standard water level and plumb line problems and also modified problems not requiring knowledge of physical principles (i.e., drawing straight up and down or straight across lines inside tipped rectangles). While males were expected to outperform females on the standard tasks, no sex differences were expected on the modified tasks. Results of an ANOVA on scores for horizontality and verticality each showed main effects for sex and task version but failed to reveal the hypothesized interaction. However, performance on the Euclidean spatial tasks was also considered in terms of overall success versus failure. While males were more successful than females in the standard format, males and females were equally successful in the modified, nonphysical, format. Hence, college aged males and females generally do not differ in spatial competence although they may be differentially influenced by task content. Findings are discussed in terms of their implications for theory and practice. It is emphasized that science educators must be especially aware of such task influences for females so that performance deficits are not mistaken for competence deficits.

Small-scale spatial cognition in pigeons.

Science.gov (United States)

Cheng, Ken; Spetch, Marcia L; Kelly, Debbie M; Bingman, Verner P

2006-05-01

Roberts and Van Veldhuizen's [Roberts, W.A., Van Veldhuizen, N., 1985. Spatial memory in pigeons on the radial maze. J. Exp. Psychol.: Anim. Behav. Proc. 11, 241-260] study on pigeons in the radial maze sparked research on landmark use by pigeons in lab-based tasks as well as variants of the radial-maze task. Pigeons perform well on open-field versions of the radial maze, with feeders scattered on the laboratory floor. Pigeons can also be trained to search precisely for buried food. The search can be based on multiple landmarks, but is sometimes controlled by just one or two landmarks, with the preferred landmarks varying across individuals. Findings are similar in landmark-based searching on a computer monitor and on a lab floor, despite many differences between the two kinds of tasks. A number of general learning principles are found in landmark-based searching, such as cue competition, generalization and peak shift, and selective attention. Pigeons also learn the geometry of the environment in which they are searching. Neurophysiological studies have implicated the hippocampal formation (HF) in avian spatial cognition, with the right hippocampus hypothesized to play a more important role in the spatial recognition of goal locations. Most recently, single-cell recording from the pigeon's hippocampal formation has revealed cells with different properties from the classic 'place' cells of rats, as well as differences in the two sides of the hippocampus.

Effect of reference frames and number of cues available on the spatial orientation of males and females in a virtual memory task.

Science.gov (United States)

Cánovas, Rosa; García, Rubén Fernández; Cimadevilla, Jose Manuel

2011-01-01

The aim of this study was to examine the influence of the number of cues and cue location in human spatial learning. To assess their importance, subjects performed variants of a virtual task called "The Boxes Room". Participants were trained to locate, in a computer-generated environment with 16 boxes, the rewarded boxes through 8 trials. In experiment I, the number of distal cues available was zero, one, two or the standard arrangement (seven cues). In experiment II, place navigation was compared based on distal landmarks (extra-maze cues placed on the walls) and proximal landmarks (proximal cues placed between the boxes). The results of experiment I demonstrated that one cue in the room is enough to obtain a good performance in the task. Experiment II showed that groups using proximal cues were slower and less accurate than groups using distal cues. In addition, our data suggest that men are better navigators than women, as they found the rewarded boxes sooner and committed fewer errors in both studies. These results indicate that performance can change depending on the number and location of available cues. Copyright © 2010 Elsevier B.V. All rights reserved.

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.

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.

Task related doses in spanish light water reactors over the period 1990-1996

International Nuclear Information System (INIS)

Aroca, J.; Montesinos, J.J.; O'Donnell, P.; Amor, I.; Butragueno, J.L.

1998-01-01

In order to evaluate in depth the effectiveness of the practical application of the ALARA principle in Spanish nuclear facilities -7 PWR (6 Westinghouse and 1 KWU-Siemens) and 2 BWR (Generic Electric), and to have a further overview of dose trends, the CSN has analysed the task related doses data over the period 1990-1996. The scope of this analysis includes the collective dose and relative relevance for 18 different refuelling outage tasks, some sub-tasks, 12 department staff, and the main consolidated dose reduction-techniques and good practices. Data has been collected from the outage reports NPPs provide according to the CSN 1.5 Safety Guide format. (Author)

Task related doses in Spanish pressurized water reactors over the period 1988-1992

Energy Technology Data Exchange (ETDEWEB)

O`Donnell, P.; Labarta, T.; Amor, I. [Subdireccion de Proteccion Radiologica, Madrid (Spain)

1995-03-01

In order to evaluate in depth the collective dose trend and its correlation with the effectiveness of the practical application of the ALARA principle in Spanish nuclear facilities, and base the different policy lines to promote this criteria, the CSN has fullfilled an analysis of the task related doses data over the period 1988-1992. Previously, the CSN had required to the utilities the compilation of their refuelling outage collective dose from 1988 according with a predeterminate number of tasks, in order to have available a representative and retrospective set of data in an homogeneous way and coherent with the international data banks on occupational exposure in NPP, as the CEC and the NEA ones. The scope of this analysis was the following: first, the collective dose summaries for outage tasks and departments for PWR and for BWR, including the minimum, maximum and average dose (and statistics data) for 18 different refuelling outage tasks and 12 personal departments for each generation of each type of rector, the task and department related collective dose trends in each plant and in each generation, and second, the dose reduction techniques having been used during that period in each plant and the relative level of adoption. In this presentation the main results and conclusions of the first part of the study are reviewed for PWR.

Cholinergic parameters and the retrieval of learned and re-learned spatial information: a study using a model of Wernicke-Korsakoff Syndrome.

Science.gov (United States)

Pires, Rita G W; Pereira, Silvia R C; Oliveira-Silva, Ieda F; Franco, Glaura C; Ribeiro, Angela M

2005-07-01

This is a factorial (2 x 2 x 2) spatial memory and cholinergic parameters study in which the factors are chronic ethanol, thiamine deficiency and naivety in Morris water maze task. Both learning and retention of the spatial version of the water maze were assessed. To assess retrograde retention of spatial information, half of the rats were pre-trained on the maze before the treatment manipulations of pyrithiamine (PT)-induced thiamine deficiency and post-tested after treatment (pre-trained group). The other half of the animals was only trained after treatment to assess anterograde amnesia (post-trained group). Thiamine deficiency, associated to chronic ethanol treatment, had a significant deleterious effect on spatial memory performance of post-trained animals. The biochemical data revealed that chronic ethanol treatment reduced acetylcholinesterase (AChE) activity in the hippocampus while leaving the neocortex unchanged, whereas thiamine deficiency reduced both cortical and hippocampal AChE activity. Regarding basal and stimulated cortical acetylcholine (ACh) release, both chronic ethanol and thiamine deficiency treatments had significant main effects. Significant correlations were found between both cortical and hippocampal AChE activity and behaviour parameters for pre-trained but not for post-trained animals. Also for ACh release, the correlation found was significant only for pre-trained animals. These biochemical parameters were decreased by thiamine deficiency and chronic ethanol treatment, both in pre-trained and post-trained animals. But the correlation with the behavioural parameters was observed only for pre-trained animals, that is, those that were retrained and assessed for retrograde retention.

Touchscreen learning deficits in Ube3a, Ts65Dn and Mecp2 mouse models of neurodevelopmental disorders with intellectual disabilities.

Science.gov (United States)

Leach, P T; Crawley, J N

2017-12-20

Mutant mouse models of neurodevelopmental disorders with intellectual disabilities provide useful translational research tools, especially in cases where robust cognitive deficits are reproducibly detected. However, motor, sensory and/or health issues consequent to the mutation may introduce artifacts that preclude testing in some standard cognitive assays. Touchscreen learning and memory tasks in small operant chambers have the potential to circumvent these confounds. Here we use touchscreen visual discrimination learning to evaluate performance in the maternally derived Ube3a mouse model of Angelman syndrome, the Ts65Dn trisomy mouse model of Down syndrome, and the Mecp2 Bird mouse model of Rett syndrome. Significant deficits in acquisition of a 2-choice visual discrimination task were detected in both Ube3a and Ts65Dn mice. Procedural control measures showed no genotype differences during pretraining phases or during acquisition. Mecp2 males did not survive long enough for touchscreen training, consistent with previous reports. Most Mecp2 females failed on pretraining criteria. Significant impairments on Morris water maze spatial learning were detected in both Ube3a and Ts65Dn, replicating previous findings. Abnormalities on rotarod in Ube3a, and on open field in Ts65Dn, replicating previous findings, may have contributed to the observed acquisition deficits and swim speed abnormalities during water maze performance. In contrast, these motor phenotypes do not appear to have affected touchscreen procedural abilities during pretraining or visual discrimination training. Our findings of slower touchscreen learning in 2 mouse models of neurodevelopmental disorders with intellectual disabilities indicate that operant tasks offer promising outcome measures for the preclinical discovery of effective pharmacological therapeutics. © 2017 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Effect of head-only sub-chronic GSM exposure on spatial memory of rats

International Nuclear Information System (INIS)

Ammari, Mohamed; Brillaud, Elsa; Lecomte, Anthony; Sakly, Mohsen; Abdelmelek, Hafedh; Seze, Rene de; Faculte des Sciences de Bizerte, Jarzouna

2008-01-01

Full text: Introduction: Low power electromagnetic fields (EMF) are suspected to produce deficit memory in rats. The study of Dubreuil et al (2003) showed that a short-term (10-15 days) exposure 'head-only' to GSM 900 MHz radio frequencies does not produce a deficit memory in adult rats. The aim of our experiment was to determine if head-only sub-chronic exposure (2 months) of rats to GSM signal for 45 min at a SAR = 1.5 W/Kg and for 15 min at 6 W/Kg induce deficit in spatial memory of rats in radial maze test. Materials and methods: Exposure system: Animals were placed in Plexiglas rockets with an individual loop antenna placed above the rat's head. Four animals were exposed at the time. Loop antennas were connected to a generator and emitted a GSM signal (900 MHz, pulsed at 217 Hz, 1/8 duty factor) 5 days / week for 8 weeks. Experimental group: 30 Sprague-Dawley male rats were randomly assigned to 5 different groups: a) 6 rats exposed 15 min at SAR = 6 W/Kg; b) 6 rats exposed 45 min at SAR = 1.5 W/g; c) 6 rats sham controls (3 for 5 min and 3 for 45 min, SAR = 0 W/Kg); d) 6 rats without any treatment and manipulation (cage control); e) 6 rats were injected (i.p) S.B.H 0.1 mg/Kg (Sigma Aldrich) as positive control group. Behavioural procedure: The radial maze protocol consists of two consecutive phases: the training task (10 days) and the test task (8 days). In the first phase, rats were trained to visit the 8 arms of the maze without returning to an arm already visited. In the second phase (8 days), a 45-min intra-trial delay was introduced after four visited arms. After the intra-delay, the rat was placed in the maze to finish the test task, which is visiting four other arms he had not visited. During the training task, exposure took place before the behavioural task. During the test task, exposure or sham-exposure took place during the intra-delay. Results and discussion: In all experiments, performance of exposed rats (1.5 and 6 W/Kg) was compared with that of

MDMA enhances hippocampal-dependent learning and memory under restrictive conditions, and modifies hippocampal spine density.

Science.gov (United States)

Abad, Sònia; Fole, Alberto; del Olmo, Nuria; Pubill, David; Pallàs, Mercè; Junyent, Fèlix; Camarasa, Jorge; Camins, Antonio; Escubedo, Elena

2014-03-01

Addictive drugs produce forms of structural plasticity in the nucleus accumbens and prefrontal cortex. The aim of this study was to investigate the impact of chronic MDMA exposure on pyramidal neurons in the CA1 region of hippocampus and drug-related spatial learning and memory changes. Adolescent rats were exposed to saline or MDMA in a regime that mimicked chronic administration. One week later, when acquisition or reference memory was evaluated in a standard Morris water maze (MWM), no differences were obtained between groups. However, MDMA-exposed animals performed better when the MWM was implemented under more difficult conditions. Animals of MDMA group were less anxious and were more prepared to take risks, as in the open field test they ventured more frequently into the central area. We have demonstrated that MDMA caused an increase in brain-derived neurotrophic factor (BDNF) expression. When spine density was evaluated, MDMA-treated rats presented a reduced density when compared with saline, but overall, training increased the total number of spines, concluding that in MDMA-group, training prevented a reduction in spine density or induced its recovery. This study provides support for the conclusion that binge administration of MDMA, known to be associated to neurotoxic damage of hippocampal serotonergic terminals, increases BDNF expression and stimulates synaptic plasticity when associated with training. In these conditions, adolescent rats perform better in a more difficult water maze task under restricted conditions of learning and memory. The effect on this task could be modulated by other behavioural changes provoked by MDMA.

Prenatal choline supplementation mitigates behavioral alterations associated with prenatal alcohol exposure in rats.

Science.gov (United States)

Thomas, Jennifer D; Idrus, Nirelia M; Monk, Bradley R; Dominguez, Hector D

2010-10-01

Prenatal alcohol exposure can alter physical and behavioral development, leading to a range of fetal alcohol spectrum disorders. Despite warning labels, pregnant women continue to drink alcohol, creating a need to identify effective interventions to reduce the severity of alcohol's teratogenic effects. Choline is an essential nutrient that influences brain and behavioral development. Recent studies indicate that choline supplementation can reduce the teratogenic effects of developmental alcohol exposure. The present study examined whether choline supplementation during prenatal ethanol treatment could mitigate the adverse effects of ethanol on behavioral development. Pregnant Sprague-Dawley rats were intubated with 6 g/kg/day ethanol in a binge-like manner from gestational days 5-20; pair-fed and ad libitum chow controls were included. During treatment, subjects from each group were intubated with either 250 mg/kg/day choline chloride or vehicle. Spontaneous alternation, parallel bar motor coordination, Morris water maze, and spatial working memory were assessed in male and female offspring. Subjects prenatally exposed to alcohol exhibited delayed development of spontaneous alternation behavior and deficits on the working memory version of the Morris water maze during adulthood, effects that were mitigated with prenatal choline supplementation. Neither alcohol nor choline influenced performance on the motor coordination task. These data indicate that choline supplementation during prenatal alcohol exposure may reduce the severity of fetal alcohol effects, particularly on alterations in tasks that require behavioral flexibility. These findings have important implications for children of women who drink alcohol during pregnancy. © 2010 Wiley-Liss, Inc.

Impairment of the spatial learning and memory induced by learned helplessness and chronic mild stress.

Science.gov (United States)

Song, Li; Che, Wang; Min-Wei, Wang; Murakami, Yukihisa; Matsumoto, Kinzo

2006-02-01

Increasing evidences indicate the concurrence and interrelationship of depression and cognitive impairments. The present study was undertaken to investigate the effects of two depressive animal models, learned helplessness (LH) and chronic mild stress (CMS), on the cognitive functions of mice in the Morris water maze task. Our results demonstrated that both LH and CMS significantly decreased the cognitive performance of stressed mice in the water maze task. The escaping latency to the platform was prolonged and the probe test percentage in the platform quadrant was reduced. These two models also increased the plasma corticosterone concentration and decreased the brain derived neurotrophic factor (BDNF) and cAMP-response element-biding protein (CREB) messenger ribonucleic acid (mRNA) levels in hippocampus, which might cause the spatial cognition deficits. Repeated treatment with antidepressant drugs, imipramine (Imi) and fluoxetine (Flu), significantly reduced the plasma corticosterone concentration and enhanced the BDNF and CREB levels. Furthermore, antidepressant treated animals showed an ameliorated cognitive performance compared with the vehicle treated stressed animals. These data suggest that both LH and CMS impair the spatial cognitive function and repeated treatment with antidepressant drugs decreases the prevalence of cognitive impairments induced by these two animal models. Those might in part be attributed to the reduced plasma corticosterone and enhanced hippocampal BDNF and CREB expressions. This study provided a better understanding of molecular mechanisms underlying interactions of depression and cognitive impairments, although animal models used in this study can mimic only some aspects of depression or cognition of human.

Beyond dizziness: virtual navigation, spatial anxiety and hippocampal volume in bilateral vestibulopathy

Directory of Open Access Journals (Sweden)

Olympia eKremmyda

2016-03-01

Full Text Available Bilateral vestibulopathy (BVP is defined as the impairment or loss of function of either the labyrinths or the eighth nerves. Patients with total BVP due to bilateral vestibular nerve section exhibit difficulties in spatial memory and navigation and show a loss of hippocampal volume. In clinical practice, most patients do not have a complete loss of function but rather an asymmetrical residual functioning of the vestibular system. The purpose of the current study was to investigate navigational ability and hippocampal atrophy in BVP patients with residual vestibular function. Fifteen patients with BVP and a group of age- and gender- matched healthy controls were examined. Self-reported questionnaires on spatial anxiety and wayfinding were used to assess the applied strategy of wayfinding and quality of life. Spatial memory and navigation were tested directly using a virtual Morris Water Maze Task. The hippocampal volume of these two groups was evaluated by voxel-based morphometry. In the patients, the questionnaire showed a higher spatial anxiety and the Morris Water Maze Task a delayed spatial learning performance. MRI revealed a significant decrease in the gray matter mid-hippocampal volume (Left: p = 0.006, Z = 4.58, Right: p < 0.001, Z = 3.63 and posterior parahippocampal volume (Right: p = 0.005, Z = 4.65, Left: p < 0.001, Z = 3.87 compared to those of healthy controls. In addition, a decrease in hippocampal formation volume correlated with a more dominant route-finding strategy. Our current findings demonstrate that even partial bilateral vestibular loss leads to anatomical and functional

Navigating a Maze with Balance Board and Wiimote

NARCIS (Netherlands)

Fikkert, F.W.; Hoeijmakers, Niek; van der Vet, P.E.; Nijholt, A.; Nijholt, Antinus; Reidsma, D.; Reidsma, Dennis; Hondorp, G.H.W.

2009-01-01

Input from the lower body in human-computer interfaces can be beneficial, enjoyable and even entertaining when users are expected to perform tasks simultaneously. Users can navigate a virtual (game) world or even an (empirical) dataset while having their hands free to issue commands. We compared the

European union water policy--tasks for implementing "Water Framework Directive" in pre-accession countries.

Science.gov (United States)

Sözen, Seval; Avcioglu, Ebru; Ozabali, Asli; Görgun, Erdem; Orhon, Derin

2003-08-01

Water Framework Directive aiming to maintain and improve the aquatic environment in the EU was launched by the European Parliament in 2000. According to this directive, control of quantity is an ancillary element in securing good water quality and therefore measures on quantity, serving the objective of ensuring good quality should also be established. Accordingly, it is a comprehensive and coordinated package that will ensure all European waters to be protected according to a common standard. Therefore, it refers to all other Directives related to water resources management such as Urban Wastewater Treatment Directive Nitrates Directive, Drinking Water Directive, Integrated Pollution Prevention Control etc. Turkey, as a candidate state targeting full-membership, should comply the necessary preparations for the implementation of the "Water Framework Directive" as soon as possible. In this study, the necessary legislative, political, institutional, and technical attempts of the pre-accession countries have been discussed and effective recommendations have been offered for future activities in Turkey.

A Validation of Cognitive Evaluation Theory.

Science.gov (United States)

McDonald, Charles H.

The role of money and other types of feedback on motivation to do a task or job has long been of interest to managers in business. To examine Deci's hypothesis concerning the effects of contingent rewards on intrinsic task interest, 42 high school students worked puzzles involving the solution of mazes and anagrams. Competence in task was made…

Female Sprague Dawley Rats Show Impaired Spatial Memory in the 8-Arm Radial Maze under Dim Blue and Red Light

OpenAIRE

Pirchl, Michael; Kemmler, Georg; Humpel, Christian

2010-01-01

Light intensity and wavelength strongly influence mood and cognition in humans and rodent animal models. The aim of the present study was to explore if dim white (7.6–17.7 lux) , blue (1.3–2.3 lux), and red light (0.8–1.4 lux) affect spatial memory of male and female Sprague Dawley rats in the 8-arm radial maze. Our data show that spatial memory significantly improved within 5 daily learning sessions (each 5 trials) under dim white light, which was not different between male and female rats. ...

Inflorescence development in petunia: through the maze of botanical terminology.

Science.gov (United States)

Castel, Rob; Kusters, Elske; Koes, Ronald

2010-05-01

Flowering plants have developed many ways to arrange their flowers. A flower-bearing branch or system of branches is called an inflorescence. The number of flowers that an inflorescence contains ranges from a single flower to endless flower-clusters. Over the past centuries, botanists have classified inflorescences based on their morphology, which has led to an unfortunate maze of complex botanical terminology. With the rise of molecular developmental biology, research has become increasingly focused on how inflorescences develop, rather than on their morphology. It is the decisions taken by groups of stem cells at the growing tips of shoots, called meristems, on when and where to produce a flower or a shoot that specify the course of inflorescence development. Modelling is a helpful aid to follow the consequences of these decisions for inflorescence development. The so-called transient model can produce the broad inflorescence types: cyme, raceme, and panicle, into which most inflorescences found in nature can be classified. The analysis of several inflorescence branching mutants has led to a solid understanding of cymose inflorescence development in petunia (Petunia hybrida). The cyme of petunia is a distinct body plan compared with the well-studied racemes of Arabidopsis and Antirrhinum, which provides an excellent opportunity to study evolutionary developmental biology (evo-devo) related questions. However, thus far, limited use has been made of this opportunity, which may, at least in part, be due to researchers getting lost in the terminology. Some general issues are discussed here, while focusing on inflorescence development in petunia.

LONG-TERM EFFICACY AND HEALTH STATUS IN PATIENTS WITH ATRIAL FIBRILLATION AFTER RADIOFREQUENCY ENDOCARDIAL CATHETER ABLATION IN MAZE REGIMEN

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M. E. Protasov

2015-01-01

Full Text Available Aim: To evaluate efficacy of endocardial radiofrequency catheter ablation (RFA in atrial fibrillation (AF in Maze regimen, to assess patients’ health status with a European Quality of Life Questionnaire (EQ-5D and cardiovascular mortality in patients after the intervention taking anticoagulants.Materials and methods: 391 patients with AF (247 of them males aged from 18 to 77 years (mean age 54.9 ± 10.1 years were examined and got treatment. All patients underwent RFA, including pulmonary vein isolation, linear ablations of the posterior wall, left atrial roof and mitral isthmus. Their health status was assessed according to efficacy of the intervention and data from EQ-5D questionnaires.Results: At 3 and 36 months after the intervention, RFA efficacy in patients with paroxysmal AF was 92% and 83.3%, respectively, and in patients with persistent AF, 89.7% and 72.4%. According to EQ-5D “thermometer”, after 36 months patients with successful catheter ablation assessed their health status as being approximately at the same level as during initial hospitalization, i.e., in patients with paroxysmal AF this scale scored at 79.74% and 81.4%, and in patients with persistent AF, at 79.94% and 81.06%, respectively. However, if the endocardial Maze procedure was unsuccessful, there was a deterioration of health status from 80.8% to 70.14% in patients with paroxysmal AF and from 77.82% to 69.46% in those with persistent AF. The same trend was observed in the analysis of other EQ-5D items. All-cause cardiovascular mortality in the subgroup with successful RFA was lower than in the subgroup with unsuccessful RFA, irrespective of AF form (p < 0.001. A 36-month mortality rate in patients with paroxysmal AF after a successful RFA was 2.1% and in patients with persistent AF, 1.2%, after unsuccessful RFA the corresponding values being 13.4% and 9.6%. Causes of death in patients with successful and unsuccessful RFA were different. After successful RFA for

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

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Hutchings, Elizabeth J.; Waller, Jennifer L.

2013-01-01

A common feature of the neuropsychiatric disorders for which antipsychotic drugs are prescribed is cognitive dysfunction, yet the effects of long-term antipsychotic treatment on cognition are largely unknown. In the current study, we evaluated the effects of long-term oral treatment with the first-generation antipsychotic haloperidol (1.0 and 2.0 mg/kg daily) and the second-generation antipsychotic risperidone (1.25 and 2.5 mg/kg daily) on the acquisition and performance of two radial-arm maze (RAM) tasks and a five-choice serial reaction-time task (5C-SRTT) in rats during days 15–60 and 84–320 days of treatment, respectively. In the RAM, neither antipsychotic significantly affected the acquisition or performance of a spatial win shift or a delayed non–match-to-position task. Conversely, in the rats administered 5C-SRTT, haloperidol was associated with profound deficits in performance, and the subjects were not able to progress through all stages of task acquisition. Depending on the dose, risperidone was associated with a greater number of trials to meet specific performance criteria during task acquisition compared with vehicle-treated controls; however, most subjects were eventually able to achieve all levels of task acquisition. Both haloperidol and risperidone also increased the number of perseverative and time-out responses during certain stages of task acquisition, and the response and reward latencies were slightly higher than controls during several stages of the study. These results in rats suggest that while long-term treatment with haloperidol or risperidone may not significantly affect spatial working or short-term memory, both antipsychotics can (depending on dose) impair sustained attention, decrease psychomotor speed, increase compulsive-type behaviors, and impair cognitive flexibility. PMID:24042161

Differential long-term effects of haloperidol and risperidone on the acquisition and performance of tasks of spatial working and short-term memory and sustained attention in rats.

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

2013-12-01

A common feature of the neuropsychiatric disorders for which antipsychotic drugs are prescribed is cognitive dysfunction, yet the effects of long-term antipsychotic treatment on cognition are largely unknown. In the current study, we evaluated the effects of long-term oral treatment with the first-generation antipsychotic haloperidol (1.0 and 2.0 mg/kg daily) and the second-generation antipsychotic risperidone (1.25 and 2.5 mg/kg daily) on the acquisition and performance of two radial-arm maze (RAM) tasks and a five-choice serial reaction-time task (5C-SRTT) in rats during days 15-60 and 84-320 days of treatment, respectively. In the RAM, neither antipsychotic significantly affected the acquisition or performance of a spatial win shift or a delayed non-match-to-position task. Conversely, in the rats administered 5C-SRTT, haloperidol was associated with profound deficits in performance, and the subjects were not able to progress through all stages of task acquisition. Depending on the dose, risperidone was associated with a greater number of trials to meet specific performance criteria during task acquisition compared with vehicle-treated controls; however, most subjects were eventually able to achieve all levels of task acquisition. Both haloperidol and risperidone also increased the number of perseverative and time-out responses during certain stages of task acquisition, and the response and reward latencies were slightly higher than controls during several stages of the study. These results in rats suggest that while long-term treatment with haloperidol or risperidone may not significantly affect spatial working or short-term memory, both antipsychotics can (depending on dose) impair sustained attention, decrease psychomotor speed, increase compulsive-type behaviors, and impair cognitive flexibility.

[Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio]. Volume 4, Health and Safety Plan (HSP); Phase 1, Task 4 Field Investigation report: Draft

Energy Technology Data Exchange (ETDEWEB)

1991-10-01

This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

Angiotensin IV and LVV-haemorphin 7 enhance spatial working memory in rats: effects on hippocampal glucose levels and blood flow.

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De Bundel, Dimitri; Smolders, Ilse; Yang, Rui; Albiston, Anthony L; Michotte, Yvette; Chai, Siew Yeen

2009-07-01

The IRAP ligands Angiotensin IV (Ang IV) and LVV-haemorphin 7 (LVV-H7) enhance performance in a range of memory paradigms in normal rats and ameliorate memory deficits in rat models for amnesia. The mechanism by which these peptides facilitate memory remains to be elucidated. In recent in vitro experiments, we demonstrated that Ang IV and LVV-H7 potentiate activity-evoked glucose uptake into hippocampal neurons. This raises the possibility that IRAP ligands may facilitate memory in hippocampus-dependent tasks through enhancement of hippocampal glucose uptake. Acute intracerebroventricular (i.c.v.) administration of 1nmol Ang IV or 0.1nmol LVV-H7 in 3 months-old Sprague-Dawley rats enhanced spatial working memory in the plus maze spontaneous alternation task. Extracellular hippocampal glucose levels were monitored before, during and after behavioral testing using in vivo microdialysis. Extracellular hippocampal glucose levels decreased significantly to about 70% of baseline when the animals explored the plus maze, but remained constant when the animals were placed into a novel control chamber. Ang IV and LVV-H7 did not significantly alter hippocampal glucose levels compared to control animals in the plus maze or control chamber. Both peptides had no effect on hippocampal blood flow as determined by laser Doppler flowmetry, excluding that either peptide increased the hippocampal supply of glucose. We demonstrated for the first time that Ang IV and LVV-H7 enhance spatial working memory in the plus maze spontaneous alternation task but no in vivo evidence was found for enhanced hippocampal glucose uptake or blood flow.

Chronic prenatal ethanol exposure alters hippocampal GABA(A) receptors and impairs spatial learning in the guinea pig.

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Iqbal, U; Dringenberg, H C; Brien, J F; Reynolds, J N

2004-04-02

Chronic prenatal ethanol exposure (CPEE) can injure the developing brain, and may lead to the fetal alcohol syndrome (FAS). Previous studies have demonstrated that CPEE upregulates gamma-aminobutyric acid type A (GABA(A)) receptor expression in the cerebral cortex, and decreases functional synaptic plasticity in the hippocampus, in the adult guinea pig. This study tested the hypothesis that CPEE increases GABA(A) receptor expression in the hippocampus of guinea pig offspring that exhibit cognitive deficits in a hippocampal-dependent spatial learning task. Timed, pregnant guinea pigs were treated with ethanol (4 g/kg maternal body weight per day), isocaloric-sucrose/pair-feeding, or water throughout gestation. GABA(A) receptor subunit protein expression in the hippocampus was measured at two development ages: near-term fetus and young adult. In young adult guinea pig offspring, CPEE increased spontaneous locomotor activity in the open-field and impaired task acquisition in the Morris water maze. CPEE did not change GABA(A) receptor subunit protein expression in the near-term fetal hippocampus, but increased expression of the beta2/3-subunit of the GABA(A) receptor in the hippocampus of young adult offspring. CPEE did not change either [(3)H]flunitrazepam binding or GABA potentiation of [(3)H]flunitrazepam binding, but decreased the efficacy of allopregnanolone potentiation of [(3)H]flunitrazepam binding, to hippocampal GABA(A) receptors in adult offspring. Correlational analysis revealed a relationship between increased spontaneous locomotor activity and growth restriction in the hippocampus induced by CPEE. Similarly, an inverse relationship was found between performance in the water maze and the efficacy of allopregnanolone potentiation of [(3)H]flunitrazepam binding in the hippocampus. These data suggest that alterations in hippocampal GABA(A) receptor expression and pharmacological properties contribute to hippocampal-related behavioral and cognitive deficits

Effects of noise and task loading on a communication task loading on a communication task

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Orrell, Dean H., II

Previous research had shown the effect of noise on a single communication task. This research has been criticized as not being representative of a real world situation since subjects allocated all of their attention to only one task. In the present study, the effect of adding a loading task to a standard noise-communication paradigm was investigated. Subjects performed both a communication task (Modified Rhyme Test; House et al. 1965) and a short term memory task (Sternberg, 1969) in simulated levels of aircraft noise (95, 105 and 115 dB overall sound pressure level (OASPL)). Task loading was varied with Sternberg's task by requiring subjects to memorize one, four, or six alphanumeric characters. Simulated aircraft noise was varied between levels of 95, 105 and 115 dB OASPL using a pink noise source. Results show that the addition of Sternberg's task and little effect on the intelligibility of the communication task while response time for the communication task increased.

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

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Sanbonmatsu, David M; Strayer, David L; Medeiros-Ward, Nathan; Watson, Jason M

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

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David M Sanbonmatsu

Full Text Available The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Who Multi-Tasks and Why? Multi-Tasking Ability, Perceived Multi-Tasking Ability, Impulsivity, and Sensation Seeking

Science.gov (United States)

Sanbonmatsu, David M.; Strayer, David L.; Medeiros-Ward, Nathan; Watson, Jason M.

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants’ perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation – high levels of impulsivity and sensation seeking – reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control - low scorers on the Operation Span task and persons high in impulsivity - tended to report higher levels of multi-tasking activity. PMID:23372720

Task demand, task management, and teamwork

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Braarud, Per Oeivind; Brendryen, Haavar

2001-03-15

The current approach to mental workload assessment in process control was evaluated in 3 previous HAMMLAB studies, by analysing the relationship between workload related measures and performance. The results showed that subjective task complexity rating was related to team's control room performance, that mental effort (NASA-TLX) was weakly related to performance, and that overall activity level was unrelated to performance. The results support the argument that general cognitive measures, i.e., mental workload, are weakly related to performance in the process control domain. This implies that other workload concepts than general mental workload are needed for valid assessment of human reliability and for valid assessment of control room configurations. An assessment of task load in process control suggested that how effort is used to handle task demand is more important then the level of effort invested to solve the task. The report suggests two main workload related concepts with a potential as performance predictors in process control: task requirements, and the work style describing how effort is invested to solve the task. The task requirements are seen as composed of individual task demand and team demand. In a similar way work style are seen as composed of individual task management and teamwork style. A framework for the development of the concepts is suggested based on a literature review and experiences from HAMMLAB research. It is suggested that operational definitions of workload concepts should be based on observable control room behaviour, to assure a potential for developing performance-shaping factors. Finally an explorative analysis of teamwork measures and performance in one study indicated that teamwork concepts are related to performance. This lends support to the suggested development of team demand and teamwork style as elements of a framework for the analysis of workload in process control. (Author)

The task-to-task communication between computers

International Nuclear Information System (INIS)

Lin Shuzi; Zhang Bingyun; Zhao Weiren

1992-01-01

The task-to-task communication is used in the Institute of High Energy Physics. The BES (Beijing Spectrometer) uses the communication mode to take some of the BEPC (Beijing Electron Positron Collider) running parameters needed by BES experiments in a periodic time. The authors describe the principle of transparent task-to-task communication and how to use it in BES on-line data acquisition system

Hippocampus and cerebellum function following imipenem treatment in male and female rats: evaluation of sex differences during developmental stage.

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Golchin, Leila; Golchin, Lale; Vahidi, Ali Asghar; Shabani, Mohammad

2013-02-15

The B-Lactam antibiotics have been suggested to have some degree of neurotoxicity in experimental animals as well as in clinical situations. This study has been elucidated the alteration in hippocampal and cerebellum function following adolescent imipenem exposure in male and female rats. Hippocampus and cerebellum related behavioral dysfunction in imipenem -treated [intraperitoneally, 40 and 80 mg/kg/day for one week from 23-day-old] rats were analyzed using explorative, motor function, learning and memory tasks [grasping, rotarod, open field shuttle box and Morris water maze tests]. Exposure to imipenem especially in high dosage impaired the motor coordination in male and female rats. There weren't any differences in grasping time in male and female rats. When the rearing and grooming frequency of their recorded in open field test, both males and females were dramatically affected by exposure to imipenem. Compared to the saline, male and female rats trained one week after imipenem injection showed significant memory deficits in the shuttle box and Morris water maze tests. Results in this study suggested that animals treated with imipenem suffer from motor activity and cognitive impairment. However, hippocampal and cerebellum functions of male and female rats were profoundly affected by exposure to imipenem while no sex-differences in the most variable were evident.

The Ameliorating Effect of Steamed and Fermented Codonopsis lanceolata on Scopolamine-Induced Memory Impairment in Mice

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Jin Bae Weon

2013-01-01

Full Text Available Codonopsis lanceolata (Campanulaceae have been traditionally used to treat lung inflammatory diseases, such as asthma, tonsillitis, and pharyngitis. The present study was performed to evaluate the cognitive-enhancing effects of steamed and fermented C. lanceolata in scopolamine-induced memory impairments in mice. Cognitive abilities were determined by the Morris water maze and passive avoidance tests. Mice orally received fermented C. lanceolata extract at doses of 100, 300, or 500 mg/kg body weight. Fermented C. lanceolata extract (500 mg/kg body weight, p.o. significantly shortened the escape latency times that were increased by scopolamine on the 4th day of trial sessions in the Morris water maze task. In addition, it exerted longer step-through latency times than those of the scopolamine-treated group in the passive avoidance test. Furthermore, the neuroprotective effects of fermented C. lanceolata extract on glutamate-induced neurocytotoxicity were investigated in HT22 cells. Fermented C. lanceolata extract showed a relative protection ratio of 59.62% at 500 μg/mL. In conclusion, fermented C. lanceolata extract ameliorated scopolamine-induced memory impairments, exerted neuroprotective effects, and improved activity compared to that found with original C. lanceolata. Further study will be required to investigate the mechanisms underlying this cognitive-enhancing activity.

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

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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.

Head west or left, east or right: interactions between memory systems in neurocognitive aging

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