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Simon Dymond - One of the best experts on this subject based on the ideXlab platform.
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Generalization of socially transmitted and instructed Avoidance.
Frontiers in behavioral neuroscience, 2015Co-Authors: Gemma Cameron, Michael W. Schlund, Simon DymondAbstract:Excessive Avoidance behavior, in which an instrumental action prevents an upcoming aversive event, is a defining feature of anxiety disorders. Left unchecked, both fear and Avoidance of potentially threatening stimuli may generalize to perceptually related stimuli and situations. The behavioral consequences of generalization mean that aversive learning experiences with specific threats may lead people to infer that classes of related stimuli are threatening, potentially dangerous, and need to be avoided, despite differences in physical form. Little is known about Avoidance generalization in humans and the learning pathways by which it may be transmitted. In the present study, we compared two pathways to Avoidance, instructions and social observation, on subsequent generalization of Avoidance behavior, fear expectancy and physiological arousal. Participants first learned that one cue was a danger cue (conditioned stimulus, CS+) and another was a safety cue (CS-). Groups then were either instructed that a Simple Avoidance response in the presence of the CS+ cancelled upcoming shock presentations (instructed-learning group) or observed a short movie showing a demonstrator performing the Avoidance response to prevent shock (observational-learning group). During generalization testing, danger and safety cues were presented along with generalization stimuli that parametrically varied in perceptual similarity to the CS+. Reinstatement of fear and Avoidance was also tested. Findings demonstrate, for the first time, generalization of socially transmitted and instructed Avoidance: both groups showed comparable generalization gradients in fear expectancy, Avoidance behavior and arousal. Return of fear was evident, suggesting that generalized Avoidance remains persistent following extinction testing. The utility of the present paradigm for research on Avoidance generalization is discussed.
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Derived Avoidance Learning: Transformation of Avoidance Response Functions in Accordance with Same and Opposite Relational Frames
The Psychological Record, 2008Co-Authors: Simon Dymond, Bryan Roche, John P. Forsyth, Robert Whelan, Julia RhodenAbstract:Two experiments were designed to replicate and extend previous findings on the transformation of Avoidance response functions in accordance with the relational frames of Same and Opposite. Participants were first exposed to nonarbitrary and arbitrary relational training and testing. Next, during Avoidance conditioning, one stimulus from the relational network signaled a Simple Avoidance response that cancelled a scheduled presentation of an aversive image and sound. The majority of participants who met the criteria for conditioned Avoidance also demonstrated derived Avoidance. Experiment 1 showed that detailed instructions were not necessary for derived transformation to occur. Experiment 2 showed that more complex patterns of transformation may emerge when another stimulus from the relational network signaled the Avoidance response. Implications for understanding clinically significant Avoidance behavior are discussed.
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Transformation of Avoidance Response Functions in Accordance with Same and Opposite Relational Frames.
Journal of the Experimental Analysis of Behavior, 2007Co-Authors: Simon Dymond, John P. Forsyth, Robert Whelan, Bryaan Roche, Julia RhodenAbstract:Research on the emergence of human Avoidance behavior in the absence of direct contact with an aversive event is somewhat limited. Consistent with work on derived relational responding, the present study sought to investigate the transformation of Avoidance response functions in accordance with the relational frames of Same and Opposite. Participants were first exposed to nonarbitrary and arbitrary relational training and testing in order to establish Same and Opposite relations among arbitrary stimuli. The training tasks were; Same–A1–B1, Same–A1–C1, Opposite–A1–B2, Opposite–A1–C2. Next, all possible combinatorially entailed (i.e., B–C and C–B) relations were tested. During the Avoidance-conditioning phase, one stimulus (B1) from the relational network signaled a Simple Avoidance response that cancelled a scheduled presentation of an aversive image and sound. All but one of the participants who met the criteria for conditioned Avoidance also demonstrated derived Avoidance by emitting the Avoidance response in the presence of C1 and the nonAvoidance response in the presence of C2. Control participants who were not exposed to relational training and testing did not show derived Avoidance. Implications of the findings for understanding clinically significant Avoidance behavior are discussed.
Fred G R Watson - One of the best experts on this subject based on the ideXlab platform.
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response of wildebeest connochaetes taurinus movements to spatial variation in long term risks from a complete predator guild
Biological Conservation, 2019Co-Authors: Egil Droge, Scott Creel, Matthew S Becker, David A Christianson, Jassiel Msoka, Fred G R WatsonAbstract:Abstract Many studies have shown that behavioral responses to the risk posed by predators can carry costs for prey by reducing fecundity or survival, with consequent effects on population dynamics. Responses to risk include increased vigilance and reduced foraging, movement to safe habitats, increases or decreases in group size, and changes in patterns of movement. While we know that prey can detect and respond to both long term (LT) and short term (ST) variation in risk, field studies have only recently begun to consider how these responses might differ. Here, we hypothesize that prey movement patterns should respond differently to cues of LT and ST variation in risk. Specifically, cues of elevated LT risk might lead to decreased movement to improve the assessment of ST risk, while elevated ST risk might favor increased movement to reduce the proximity or duration of risks that are already assessed to be acute. We further hypothesize that decreases in movement are likely to be a general response to LT risk, while responses to ST risk are likely to vary in a manner that depends on the type of predator. In Liuwa Plain National Park, we found that wildebeest movements responded to the local intensity of predator use (LT risk), after controlling for other seasonal, diurnal and bottom-up effects. Speed decreased considerably and turning angles increased considerably, combining to markedly decrease linear movements. In contrast, immediate encounters with predators (ST risk) typically provoked fast, linear flight, and this effect was stronger for encounters with coursing predators. The effect of long term risk was to cause wildebeest to move more slowly and less linearly, i.e. to slow down and turn around, as part of a suite of behavioral responses, which also includes increased vigilance, that promote cautious assessment of ST risks when in locations with high levels of LT risk. This result has broad implications of understanding the influence of predation risk on foraging patterns of ungulates as this relationship is much more complex than Simple Avoidance of areas of ‘high risk’.
Julia Rhoden - One of the best experts on this subject based on the ideXlab platform.
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Derived Avoidance Learning: Transformation of Avoidance Response Functions in Accordance with Same and Opposite Relational Frames
The Psychological Record, 2008Co-Authors: Simon Dymond, Bryan Roche, John P. Forsyth, Robert Whelan, Julia RhodenAbstract:Two experiments were designed to replicate and extend previous findings on the transformation of Avoidance response functions in accordance with the relational frames of Same and Opposite. Participants were first exposed to nonarbitrary and arbitrary relational training and testing. Next, during Avoidance conditioning, one stimulus from the relational network signaled a Simple Avoidance response that cancelled a scheduled presentation of an aversive image and sound. The majority of participants who met the criteria for conditioned Avoidance also demonstrated derived Avoidance. Experiment 1 showed that detailed instructions were not necessary for derived transformation to occur. Experiment 2 showed that more complex patterns of transformation may emerge when another stimulus from the relational network signaled the Avoidance response. Implications for understanding clinically significant Avoidance behavior are discussed.
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Transformation of Avoidance Response Functions in Accordance with Same and Opposite Relational Frames.
Journal of the Experimental Analysis of Behavior, 2007Co-Authors: Simon Dymond, John P. Forsyth, Robert Whelan, Bryaan Roche, Julia RhodenAbstract:Research on the emergence of human Avoidance behavior in the absence of direct contact with an aversive event is somewhat limited. Consistent with work on derived relational responding, the present study sought to investigate the transformation of Avoidance response functions in accordance with the relational frames of Same and Opposite. Participants were first exposed to nonarbitrary and arbitrary relational training and testing in order to establish Same and Opposite relations among arbitrary stimuli. The training tasks were; Same–A1–B1, Same–A1–C1, Opposite–A1–B2, Opposite–A1–C2. Next, all possible combinatorially entailed (i.e., B–C and C–B) relations were tested. During the Avoidance-conditioning phase, one stimulus (B1) from the relational network signaled a Simple Avoidance response that cancelled a scheduled presentation of an aversive image and sound. All but one of the participants who met the criteria for conditioned Avoidance also demonstrated derived Avoidance by emitting the Avoidance response in the presence of C1 and the nonAvoidance response in the presence of C2. Control participants who were not exposed to relational training and testing did not show derived Avoidance. Implications of the findings for understanding clinically significant Avoidance behavior are discussed.
Kathleen Knight Abowitz - One of the best experts on this subject based on the ideXlab platform.
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A Pragmatist Revisioning of Resistance Theory
American Educational Research Journal, 2000Co-Authors: Kathleen Knight AbowitzAbstract:Resistance theorists in education urge educators to evaluate the moral and political potential of opposition in schools. The scholarship of resistance calls us to examine oppositional acts of students in school settings as moral and political expressions of oppression. Resistance theorizing over the past several decades has not, however, adequately explored the idea that resistance is communication; that is, a means of signaling and constructing new meanings, and of building a discourse around particular problems of exclusion or inequality. In this paper, I use pragmatist theories of inquiry and communication to interpret and critique resistance theories in education. Using Dewey and Bentley's notion of transactionalism (1946), I present a theoretical framework for future inquiry into school opposition. Interpreting resistance theory through a pragmatist lens leads to a more relational reading of resistance, and can promote school-based inquiry (rather than Simple Avoidance or punishment) directed toward ...
Bingjun Xiao - One of the best experts on this subject based on the ideXlab platform.
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DAC - Defect tolerance in nanodevice-based programmable interconnects: utilization beyond Avoidance
Proceedings of the 50th Annual Design Automation Conference on - DAC '13, 2013Co-Authors: Jason Cong, Bingjun XiaoAbstract:This work focuses on defect tolerance for nanodevice-based programmable interconnects of FPGAs. First, we show that the stuck-closed defects of nanodevices have a much higher impact than the stuck-open defects. Instead of simply avoiding the stuck-closed defects, we use them by treating them as shorting constraints in the routing. We develop a scalable algorithm to perform timing-driven routing under these extra constraints. We also enhance the placement algorithm to recover logic blocks which become virtually unusable due to shorted pins. Simulation results show that at the up-to-date level of nanodevice defects (108--1011x higher than CMOS), compared to the Simple Avoidance method, our approach reduces the degradation of resource usage by 87%, improves the routability by 37%, and reduce the degradation of circuit performance by 36%, at a negligible overhead of tool runtime.
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FPGA - Defect recovery in nanodevice-based programmable interconnects (abstract only)
Proceedings of the ACM SIGDA international symposium on Field programmable gate arrays - FPGA '13, 2013Co-Authors: Jason Cong, Bingjun XiaoAbstract:This work focuses on defect tolerance for nanodevice-based programmable interconnects of FPGAs. A single nanodevice can function as a routing switch in place of a pass transistor and its six-transistor SRAM cell in conventional FPGAs. Defects of nanodevices in programmable interconnects are manifested as losses of configurability and can be categorized into stuck- open defect and stuck- closed defect. First, we show that the stuck-closed defects of nanodevices have a much higher impact than the stuck-open defects. Instead of simply avoiding the stuck-closed defects, we recover them by treating them as shorting constraints in the routing. We develop a scalable algorithm to perform timing-driven routing under these extra constraints. We extend the idea of the resource negotiation to balance the goals of timing and routability under shorting constraints. We also develop several techniques to guide the router to map the shorting clusters to those nets with more shared paths for better utilization of routing resources while automatically balancing it with circuit performance. We also enhance the placement algorithm to recover logic blocks which become virtually unusable due to shorted pins. Simulation results show that at the up-to-date level of nanodevice defects (108-1011x higher than CMOS), compared to the Simple Avoidance method, our approach reduces the degradation of resource usage by 87%, improves the routability by 37%, and reduce the degradation of circuit performance by 36%, at a negligible overhead of tool runtime.