The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Victor H. Denenberg - One of the best experts on this subject based on the ideXlab platform.
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in two species females exhibit superior working memory and inferior reference memory on the water Radial Arm Maze
Physiology & Behavior, 2000Co-Authors: Heather A. Bimonte, Lynn A. Hyde, Blair J Hoplight, Victor H. DenenbergAbstract:Male and female mice and rats were tested on a water escape version of the Radial-Arm Maze designed to measure working and reference memory. In both species, females exhibited superior working memory during acquisition, and were better able to handle a higher memory load. However, male mice and rats exhibited better reference memory than females during the asymptotic portion of testing. Our data suggest that females may be better at working memory when both working and reference memory information must be learned simultaneously, and males better at reference memory when it has been differentiated from working memory.
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Non-spatial water Radial-Arm Maze learning in mice.
Brain Research, 2000Co-Authors: Lynn A. Hyde, Gordon F. Sherman, Victor H. DenenbergAbstract:Recently, we published a method for examining working and reference memory in mice using a spatial version of the water Radial-Arm Maze. Here we describe a non-spatial version of the same Maze. BXSB mice were able to learn the Maze as shown by the decrease in the number of working and reference memory errors over sessions. This Maze was used to examine learning differences between males and females and between mice with misplaced clusters of neurons in layer I of cortex (ectopias) and those without. In a prior study using the spatial version of the water Radial-Arm Maze, male BXSB mice had poorer working memory than females during the acquisition phase. Similarly, in this study male BXSB mice demonstrated impaired working memory during the asymptotic phase of non-spatial Radial-Arm Maze learning. Two prior studies showed that mice with neocortical ectopias demonstrated working memory impairments compared to non-ectopic littermates in the spatial version of the water Radial-Arm Maze. Contrary to this, in the non-spatial Radial-Arm Maze used here, ectopic mice were not impaired in working memory and showed better memory when the working memory ‘load’ was the highest. Overall, both versions of the Maze can be useful tools to assess spatial and non-spatial working and reference memory in mice.
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Sex differences in vicarious trial-and-error behavior during Radial Arm Maze learning.
Physiology & Behavior, 2000Co-Authors: Heather A. Bimonte, Victor H. DenenbergAbstract: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.
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water version of the Radial Arm Maze learning in three inbred strains of mice
Brain Research, 1998Co-Authors: Lynn A. Hyde, Blair J Hoplight, Victor H. DenenbergAbstract:The conventional land Radial-Arm Maze has several disadvantages, including requiring a complicated automated apparatus, the elimination of odors as cues, and the use of food deprivation. We have created a water version of the Maze, based on the principles of the land version, which maintains the advantages and excludes some of the disadvantages. In our Maze, BXSB and C57BL/6 mice significantly reduced the number of working and reference memory errors committed over sessions, while NZB mice did not. For each strain, as the working memory 'load' increased during a session, the number of errors increased. However, with practice the BXSB and C57BL/6 strains were able to handle this memory load more effectively. Mice were able to learn the Maze without extensive adaptation, training, or testing and they did not exhibit 'chaining'. This Maze can also be considered to be an example of a water win-shift task that mice can easily learn. Therefore, the water version of the Radial-Arm Maze can be a simple and useful tool for studying rodent learning and memory.
Anthony G Phillips - One of the best experts on this subject based on the ideXlab platform.
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thalamic cortical striatal circuitry subserves working memory during delayed responding on a Radial Arm Maze
The Journal of Neuroscience, 1999Co-Authors: Stan B Floresco, Deanna N Braaksma, Anthony G PhillipsAbstract:The medial dorsal nuclei of the thalamus (MDNt), the prefrontal cortex, and the ventral striatum form an interconnected neural circuit that may subserve certain types of working memory. The present series of experiments investigated functional interactions between these brain regions in rats during the performance of delayed and nondelayed spatially cued Radial-Arm Maze tasks. In Experiment 1, transient inactivation of the MDNt by a bilateral injection of lidocaine selectively disrupted performance on a delayed task but not on a nondelayed random foraging version of the Radial Arm Maze task. In Experiment 2, asymmetrical lidocaine injections into the MDNt on one side of the brain and the prefrontal cortex on the other transiently disconnected these two brain regions and significantly impaired foraging during the delayed task. Similarly, disconnections between the prefrontal cortex and the nucleus accumbens also disrupted foraging on this task, whereas disconnections between the MDNt and the nucleus accumbens had no effect. These data suggest that serial transmission of information among the MDNt, the prefrontal cortex, and the nucleus accumbens is required when trial-unique, short-term spatial memory is used to guide prospective search behavior. The results are discussed with respect to a distributed neural network linking limbic, thalamic, cortical, and striatal regions, which mediates executive functions of working memory.
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Thalamic–Cortical–Striatal Circuitry Subserves Working Memory during Delayed Responding on a Radial Arm Maze
The Journal of Neuroscience, 1999Co-Authors: Stan B Floresco, Deanna N Braaksma, Anthony G PhillipsAbstract:The medial dorsal nuclei of the thalamus (MDNt), the prefrontal cortex, and the ventral striatum form an interconnected neural circuit that may subserve certain types of working memory. The present series of experiments investigated functional interactions between these brain regions in rats during the performance of delayed and nondelayed spatially cued Radial-Arm Maze tasks. In Experiment 1, transient inactivation of the MDNt by a bilateral injection of lidocaine selectively disrupted performance on a delayed task but not on a nondelayed random foraging version of the Radial Arm Maze task. In Experiment 2, asymmetrical lidocaine injections into the MDNt on one side of the brain and the prefrontal cortex on the other transiently disconnected these two brain regions and significantly impaired foraging during the delayed task. Similarly, disconnections between the prefrontal cortex and the nucleus accumbens also disrupted foraging on this task, whereas disconnections between the MDNt and the nucleus accumbens had no effect. These data suggest that serial transmission of information among the MDNt, the prefrontal cortex, and the nucleus accumbens is required when trial-unique, short-term spatial memory is used to guide prospective search behavior. The results are discussed with respect to a distributed neural network linking limbic, thalamic, cortical, and striatal regions, which mediates executive functions of working memory.
Edward D Levin - One of the best experts on this subject based on the ideXlab platform.
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interaction of nicotinic and histamine h3 systems in the Radial Arm Maze repeated acquisition task
European Journal of Pharmacology, 2007Co-Authors: Ehsan Kholdebarin, Channelle N. Christopher, Patrick D Caldwell, Paul W Blackwelder, Edward D LevinAbstract:Abstract Nicotinic systems have been found in a variety of studies to play important roles in cognitive function. Nicotinic involvement in different aspects of cognitive function such as learning vs. memory may differ. We have found in rats that the spatial repeated acquisition task in the Radial-Arm Maze is significantly improved by low doses of the nicotinic receptor antagonist mecamylamine, the atypical nicotinic receptor ligand lobeline, as well as the α7 nicotinic receptor agonist ARR-17779. Interestingly, nicotine in the same dose range that improves working memory in the win-shift Radial Maze task was not effective in improving repeated acquisition performance. Nicotinic systems interact with a variety of other neural systems. Differential involvement of these extended effects with learning vs. memory may help explain differential effects of nicotinic drugs with these cognitive functions. Histamine H 3 receptor antagonists have been shown by some studies to improve cognitive function, but others have not found this effect and some have found impairment. Nicotine stimulates the release of histamine. This effect may counter other cascading effects of nicotine in the performance of learning and memory tasks. A specific test of this hypothesis involves our study of nicotine (0.1–0.4 mg/kg) interactions with the histamine H 3 receptor antagonist thioperamide (2.5–10 mg/kg) on learning memory in the repeated acquisition test in the Radial-Arm Maze. The highest dose of thioperamide tested caused a significant choice accuracy impairment, which was most evident during the later portions of the learning curve. The highest dose of nicotine did not change overall errors but did cause a significant impairment in learning over trials. The choice accuracy impairment induced by thioperamide was significantly attenuated by nicotine (0.4 mg/kg). The learning impairment caused by the highest dose of nicotine was significantly attenuated by thioperamide. Thioperamide also caused a slowing of response, an effect, which was attenuated by nicotine co-administration. The repeated acquisition test can help differentiate acute drug effects on learning. Nicotine and thioperamide effectively reversed each other's choice accuracy impairment even though each by itself impaired accuracy.
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Interaction of nicotinic and histamine H(3) systems in the Radial-Arm Maze repeated acquisition task.
European journal of pharmacology, 2007Co-Authors: Ehsan Kholdebarin, N. Channelle Christopher, D Patrick Caldwell, W Paul Blackwelder, Edward D LevinAbstract:Nicotinic systems have been found in a variety of studies to play important roles in cognitive function. Nicotinic involvement in different aspects of cognitive function such as learning vs. memory may differ. We have found in rats that the spatial repeated acquisition task in the Radial-Arm Maze is significantly improved by low doses of the nicotinic receptor antagonist mecamylamine, the atypical nicotinic receptor ligand lobeline, as well as the alpha7 nicotinic receptor agonist ARR-17779. Interestingly, nicotine in the same dose range that improves working memory in the win-shift Radial Maze task was not effective in improving repeated acquisition performance. Nicotinic systems interact with a variety of other neural systems. Differential involvement of these extended effects with learning vs. memory may help explain differential effects of nicotinic drugs with these cognitive functions. Histamine H(3) receptor antagonists have been shown by some studies to improve cognitive function, but others have not found this effect and some have found impairment. Nicotine stimulates the release of histamine. This effect may counter other cascading effects of nicotine in the performance of learning and memory tasks. A specific test of this hypothesis involves our study of nicotine (0.1-0.4 mg/kg) interactions with the histamine H(3) receptor antagonist thioperamide (2.5-10 mg/kg) on learning memory in the repeated acquisition test in the Radial-Arm Maze. The highest dose of thioperamide tested caused a significant choice accuracy impairment, which was most evident during the later portions of the learning curve. The highest dose of nicotine did not change overall errors but did cause a significant impairment in learning over trials. The choice accuracy impairment induced by thioperamide was significantly attenuated by nicotine (0.4 mg/kg). The learning impairment caused by the highest dose of nicotine was significantly attenuated by thioperamide. Thioperamide also caused a slowing of response, an effect, which was attenuated by nicotine co-administration. The repeated acquisition test can help differentiate acute drug effects on learning. Nicotine and thioperamide effectively reversed each other's choice accuracy impairment even though each by itself impaired accuracy.
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Lobeline-induced learning improvement of rats in the Radial-Arm Maze.
Pharmacology Biochemistry and Behavior, 2003Co-Authors: Edward D Levin, Channelle N. ChristopherAbstract:Lobeline is a nicotinic ligand with some nicotine-like effects, but with some atypical effects as well, including actions as a nicotinic antagonist. Lobeline, like nicotine, has been found to significantly improve memory function as well as provide anxiolytic-like effects in the elevated plus Maze. Lobeline effects on learning remain to be fully characterized. Nicotine has been found to improve learning of shock avoidance tasks. Other nicotinic agonists also have been shown to improve learning performance. However, this effect is limited. In some tasks, nicotine has been found to cause deficits. In the current study, effects of lobeline and nicotine injections were assessed in a repeated acquisition procedure in the Radial-Arm Maze for 3 weeks of drug administration. Lobeline (0.3 and 0.9 mg/kg) improved learning on the Radial-Arm Maze. Neither nicotine dose (0.1 and 0.3 mg/kg) improved learning. This nicotine dose range was previously found to improve post-acquisition working memory performance in the Radial-Arm Maze. The atypical effects of lobeline may underlie its greater efficacy than nicotine for improving repeated acquisition. The effect of lobeline improving learning may be useful in the development of novel treatments for learning deficits.
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nicotine dizocilpine interactions and working and reference memory performance of rats in the Radial Arm Maze
Pharmacology Biochemistry and Behavior, 1998Co-Authors: Edward D Levin, Chetan Bettegowda, Tiffaini Weaver, Channelle N. ChristopherAbstract:Both nicotinic cholinergic and NMDA glutaminergic systems are important for memory function. Nicotine has been found repeatedly to significantly improve working memory performance in the Radial-Arm Maze. The NMDA antagonist dizocilpine has been found to impair working memory performance. There is neurophArmacological evidence that these two systems are functionally related. Nicotine is potent at releasing many transmitters including glutamate. The current study was conducted to examine the interaction of nicotinic and NMDA systems with regard to working and reference memory. Rats were trained on a working/reference procedure on a 16-Arm Radial Maze. After acquisition, they were administered nicotine (0, 0.2, and 0.4 mg/kg) and dizocilpine (0, 100, and 200 μg/kg) alone or in combination in a repeated measures, counterbalanced design. As seen previously, nicotine at a dose of 0.2 mg/kg caused a significant improvement in working but not reference memory performance in the Radial-Arm Maze. The 200 μg/kg dose of dizocilpine made the rats nonresponsive on the Maze so that choice accuracy could not be assessed. The 100 μg/kg dose of dizocilpine caused significant impairments in both working and reference memory. The 0.4 mg/kg dose of nicotine significantly attenuated the dizocilpine-induced deficit in both working and reference memory. NMDA blockade impairs working and reference memory and blocks the expression of the working memory improvement caused by 0.2 mg/kg of nicotine. However, a higher dose of 0.4 mg/kg of nicotine is effective at attenuating the dizocilpine-induced deficit, even though this dose alone is not effective in improving performance. A second study examined the effects of a lower dose range of dizocilpine. Comensurately smaller memory impairments were seen with lower doses of dizocilpine down to 12.5 μg/kg, which did not produce any significant effects on memory performance or response latency. Nicotine had a more modest effect in attenuating the smaller deficits caused by these lower doses of dizocilpine. These studies provide evidence for important interactions between nicotinic and NMDA systems with regard to memory function.
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Nicotine–Dizocilpine Interactions and Working and Reference Memory Performance of Rats in the Radial-Arm Maze
Pharmacology Biochemistry and Behavior, 1998Co-Authors: Edward D Levin, Chetan Bettegowda, Tiffaini Weaver, N. Channelle ChristopherAbstract:Both nicotinic cholinergic and NMDA glutaminergic systems are important for memory function. Nicotine has been found repeatedly to significantly improve working memory performance in the Radial-Arm Maze. The NMDA antagonist dizocilpine has been found to impair working memory performance. There is neurophArmacological evidence that these two systems are functionally related. Nicotine is potent at releasing many transmitters including glutamate. The current study was conducted to examine the interaction of nicotinic and NMDA systems with regard to working and reference memory. Rats were trained on a working/reference procedure on a 16-Arm Radial Maze. After acquisition, they were administered nicotine (0, 0.2, and 0.4 mg/kg) and dizocilpine (0, 100, and 200 μg/kg) alone or in combination in a repeated measures, counterbalanced design. As seen previously, nicotine at a dose of 0.2 mg/kg caused a significant improvement in working but not reference memory performance in the Radial-Arm Maze. The 200 μg/kg dose of dizocilpine made the rats nonresponsive on the Maze so that choice accuracy could not be assessed. The 100 μg/kg dose of dizocilpine caused significant impairments in both working and reference memory. The 0.4 mg/kg dose of nicotine significantly attenuated the dizocilpine-induced deficit in both working and reference memory. NMDA blockade impairs working and reference memory and blocks the expression of the working memory improvement caused by 0.2 mg/kg of nicotine. However, a higher dose of 0.4 mg/kg of nicotine is effective at attenuating the dizocilpine-induced deficit, even though this dose alone is not effective in improving performance. A second study examined the effects of a lower dose range of dizocilpine. Comensurately smaller memory impairments were seen with lower doses of dizocilpine down to 12.5 μg/kg, which did not produce any significant effects on memory performance or response latency. Nicotine had a more modest effect in attenuating the smaller deficits caused by these lower doses of dizocilpine. These studies provide evidence for important interactions between nicotinic and NMDA systems with regard to memory function.
Stan B Floresco - One of the best experts on this subject based on the ideXlab platform.
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thalamic cortical striatal circuitry subserves working memory during delayed responding on a Radial Arm Maze
The Journal of Neuroscience, 1999Co-Authors: Stan B Floresco, Deanna N Braaksma, Anthony G PhillipsAbstract:The medial dorsal nuclei of the thalamus (MDNt), the prefrontal cortex, and the ventral striatum form an interconnected neural circuit that may subserve certain types of working memory. The present series of experiments investigated functional interactions between these brain regions in rats during the performance of delayed and nondelayed spatially cued Radial-Arm Maze tasks. In Experiment 1, transient inactivation of the MDNt by a bilateral injection of lidocaine selectively disrupted performance on a delayed task but not on a nondelayed random foraging version of the Radial Arm Maze task. In Experiment 2, asymmetrical lidocaine injections into the MDNt on one side of the brain and the prefrontal cortex on the other transiently disconnected these two brain regions and significantly impaired foraging during the delayed task. Similarly, disconnections between the prefrontal cortex and the nucleus accumbens also disrupted foraging on this task, whereas disconnections between the MDNt and the nucleus accumbens had no effect. These data suggest that serial transmission of information among the MDNt, the prefrontal cortex, and the nucleus accumbens is required when trial-unique, short-term spatial memory is used to guide prospective search behavior. The results are discussed with respect to a distributed neural network linking limbic, thalamic, cortical, and striatal regions, which mediates executive functions of working memory.
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Thalamic–Cortical–Striatal Circuitry Subserves Working Memory during Delayed Responding on a Radial Arm Maze
The Journal of Neuroscience, 1999Co-Authors: Stan B Floresco, Deanna N Braaksma, Anthony G PhillipsAbstract:The medial dorsal nuclei of the thalamus (MDNt), the prefrontal cortex, and the ventral striatum form an interconnected neural circuit that may subserve certain types of working memory. The present series of experiments investigated functional interactions between these brain regions in rats during the performance of delayed and nondelayed spatially cued Radial-Arm Maze tasks. In Experiment 1, transient inactivation of the MDNt by a bilateral injection of lidocaine selectively disrupted performance on a delayed task but not on a nondelayed random foraging version of the Radial Arm Maze task. In Experiment 2, asymmetrical lidocaine injections into the MDNt on one side of the brain and the prefrontal cortex on the other transiently disconnected these two brain regions and significantly impaired foraging during the delayed task. Similarly, disconnections between the prefrontal cortex and the nucleus accumbens also disrupted foraging on this task, whereas disconnections between the MDNt and the nucleus accumbens had no effect. These data suggest that serial transmission of information among the MDNt, the prefrontal cortex, and the nucleus accumbens is required when trial-unique, short-term spatial memory is used to guide prospective search behavior. The results are discussed with respect to a distributed neural network linking limbic, thalamic, cortical, and striatal regions, which mediates executive functions of working memory.
Deanna N Braaksma - One of the best experts on this subject based on the ideXlab platform.
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thalamic cortical striatal circuitry subserves working memory during delayed responding on a Radial Arm Maze
The Journal of Neuroscience, 1999Co-Authors: Stan B Floresco, Deanna N Braaksma, Anthony G PhillipsAbstract:The medial dorsal nuclei of the thalamus (MDNt), the prefrontal cortex, and the ventral striatum form an interconnected neural circuit that may subserve certain types of working memory. The present series of experiments investigated functional interactions between these brain regions in rats during the performance of delayed and nondelayed spatially cued Radial-Arm Maze tasks. In Experiment 1, transient inactivation of the MDNt by a bilateral injection of lidocaine selectively disrupted performance on a delayed task but not on a nondelayed random foraging version of the Radial Arm Maze task. In Experiment 2, asymmetrical lidocaine injections into the MDNt on one side of the brain and the prefrontal cortex on the other transiently disconnected these two brain regions and significantly impaired foraging during the delayed task. Similarly, disconnections between the prefrontal cortex and the nucleus accumbens also disrupted foraging on this task, whereas disconnections between the MDNt and the nucleus accumbens had no effect. These data suggest that serial transmission of information among the MDNt, the prefrontal cortex, and the nucleus accumbens is required when trial-unique, short-term spatial memory is used to guide prospective search behavior. The results are discussed with respect to a distributed neural network linking limbic, thalamic, cortical, and striatal regions, which mediates executive functions of working memory.
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Thalamic–Cortical–Striatal Circuitry Subserves Working Memory during Delayed Responding on a Radial Arm Maze
The Journal of Neuroscience, 1999Co-Authors: Stan B Floresco, Deanna N Braaksma, Anthony G PhillipsAbstract:The medial dorsal nuclei of the thalamus (MDNt), the prefrontal cortex, and the ventral striatum form an interconnected neural circuit that may subserve certain types of working memory. The present series of experiments investigated functional interactions between these brain regions in rats during the performance of delayed and nondelayed spatially cued Radial-Arm Maze tasks. In Experiment 1, transient inactivation of the MDNt by a bilateral injection of lidocaine selectively disrupted performance on a delayed task but not on a nondelayed random foraging version of the Radial Arm Maze task. In Experiment 2, asymmetrical lidocaine injections into the MDNt on one side of the brain and the prefrontal cortex on the other transiently disconnected these two brain regions and significantly impaired foraging during the delayed task. Similarly, disconnections between the prefrontal cortex and the nucleus accumbens also disrupted foraging on this task, whereas disconnections between the MDNt and the nucleus accumbens had no effect. These data suggest that serial transmission of information among the MDNt, the prefrontal cortex, and the nucleus accumbens is required when trial-unique, short-term spatial memory is used to guide prospective search behavior. The results are discussed with respect to a distributed neural network linking limbic, thalamic, cortical, and striatal regions, which mediates executive functions of working memory.
