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Frank W Ohl - One of the best experts on this subject based on the ideXlab platform.
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electrical stimulation of lateral habenula during Learning frequency dependent effects on acquisition but not retrieval of a two way active Avoidance response
PLOS ONE, 2013Co-Authors: Anton Ilango, Jason Shumake, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:The lateral habenula (LHb) is an epithalamic structure involved in signaling reward omission and aversive stimuli, and it inhibits dopaminergic neurons during motivated behavior. Less is known about LHb involvement in the acquisition and retrieval of Avoidance Learning. Our previous studies indicated that brief electrical stimulation of the LHb, time-locked to the Avoidance of aversive footshock (presumably during the positive affective “relief” state that occurs when an aversive outcome is averted), inhibited the acquisition of Avoidance Learning. In the present study, we used the same paradigm to investigate different frequencies of LHb stimulation. The effect of 20 Hz vs. 50 Hz vs. 100 Hz stimulation was investigated during two phases, either during acquisition or retrieval in Mongolian gerbils. The results indicated that 50 Hz, but not 20 Hz, was sufficient to produce a long-term impairment in Avoidance Learning, and was somewhat more effective than 100 Hz in this regard. None of the stimulation parameters led to any effects on retrieval of Avoidance Learning, nor did they affect general motor activity. This suggests that, at frequencies in excess of the observed tonic firing rates of LHb neurons (>1–20 Hz), LHb stimulation may serve to interrupt the consolidation of new Avoidance memories. However, these stimulation parameters are not capable of modifying Avoidance memories that have already undergone extensive consolidation.
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the role of dopamine in the context of aversive stimuli with particular reference to acoustically signaled Avoidance Learning
Frontiers in Neuroscience, 2012Co-Authors: Anton Ilango, Jason Shumake, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:Learning from punishment is a powerful means for behavioral adaptation with high relevance for various mechanisms of self-protection. Several studies have explored the contribution of released dopamine (DA) or responses of DA neurons on reward seeking using rewards such as food, water, and sex. Phasic DA signals evoked by rewards or conditioned reward predictors are well documented, as are modulations of these signals by such parameters as reward magnitude, probability, and deviation of actually occurring from expected rewards. Less attention has been paid to DA neuron firing and DA release in response to aversive stimuli, and the prediction and Avoidance of punishment. In this review, we first focus on DA changes in response to aversive stimuli as measured by microdialysis and voltammetry followed by the change in electrophysiological signatures by aversive stimuli and fearful events. We subsequently focus on the role of DA and effect of DA manipulations on signaled Avoidance Learning, which consists of Learning the significance of a warning cue through Pavlovian associations and the execution of an instrumental Avoidance response. We present a coherent framework utilizing the data on microdialysis, voltammetry, electrophysiological recording, electrical brain stimulation, and behavioral analysis. We end by outlining current gaps in the literature and proposing future directions aimed at incorporating technical and conceptual progress to understand the involvement of reward circuit on punishment based decisions.
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differential neuromodulation of acquisition and retrieval of Avoidance Learning by the lateral habenula and ventral tegmental area
The Journal of Neuroscience, 2010Co-Authors: Jason Shumake, Anton Ilango, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:Several studies suggest an opponent functional relationship between the lateral habenula (LHb) and the ventral tegmental area (VTA). Previous work has linked LHb activation to the inhibition of dopaminergic neurons during loss of reward, as well as to deficits in escape and Avoidance Learning. We hypothesized that a dopamine signal might underlie the negative reinforcement of Avoidance responses and that LHb activation could block this signal and thereby cause Avoidance deficits. To test this idea, we implanted stimulating electrodes in either the VTA or LHb of gerbils engaged in two-way active Avoidance Learning, a task that shows Learning-associated dopamine changes and that is acquired faster following LHb lesions. We delivered brief electrical brain stimulation whenever the animal performed a correct response, i.e., when the successful Avoidance of foot shock was hypothesized to trigger an intrinsic reward signal. During the acquisition phase, VTA stimulation improved Avoidance performance, while LHb stimulation impaired it. VTA stimulation appeared to improve both acquisition and asymptotic performance of the Avoidance response, as VTA-stimulated animals reached above-normal performance but reverted to normal responding when stimulation was discontinued. The effects of LHb stimulation during Avoidance acquisition were long lasting and persisted even after stimulation was discontinued. However, when given after successful acquisition of Avoidance behavior, LHb stimulation had no effect, indicating that LHb stimulation specifically impaired Avoidance acquisition without affecting memory retrieval or motivation or ability to perform the Avoidance response. These results demonstrate opponent roles of LHb and VTA during acquisition but not during retrieval of Avoidance Learning.
Anton Ilango - One of the best experts on this subject based on the ideXlab platform.
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electrical stimulation of lateral habenula during Learning frequency dependent effects on acquisition but not retrieval of a two way active Avoidance response
PLOS ONE, 2013Co-Authors: Anton Ilango, Jason Shumake, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:The lateral habenula (LHb) is an epithalamic structure involved in signaling reward omission and aversive stimuli, and it inhibits dopaminergic neurons during motivated behavior. Less is known about LHb involvement in the acquisition and retrieval of Avoidance Learning. Our previous studies indicated that brief electrical stimulation of the LHb, time-locked to the Avoidance of aversive footshock (presumably during the positive affective “relief” state that occurs when an aversive outcome is averted), inhibited the acquisition of Avoidance Learning. In the present study, we used the same paradigm to investigate different frequencies of LHb stimulation. The effect of 20 Hz vs. 50 Hz vs. 100 Hz stimulation was investigated during two phases, either during acquisition or retrieval in Mongolian gerbils. The results indicated that 50 Hz, but not 20 Hz, was sufficient to produce a long-term impairment in Avoidance Learning, and was somewhat more effective than 100 Hz in this regard. None of the stimulation parameters led to any effects on retrieval of Avoidance Learning, nor did they affect general motor activity. This suggests that, at frequencies in excess of the observed tonic firing rates of LHb neurons (>1–20 Hz), LHb stimulation may serve to interrupt the consolidation of new Avoidance memories. However, these stimulation parameters are not capable of modifying Avoidance memories that have already undergone extensive consolidation.
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the role of dopamine in the context of aversive stimuli with particular reference to acoustically signaled Avoidance Learning
Frontiers in Neuroscience, 2012Co-Authors: Anton Ilango, Jason Shumake, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:Learning from punishment is a powerful means for behavioral adaptation with high relevance for various mechanisms of self-protection. Several studies have explored the contribution of released dopamine (DA) or responses of DA neurons on reward seeking using rewards such as food, water, and sex. Phasic DA signals evoked by rewards or conditioned reward predictors are well documented, as are modulations of these signals by such parameters as reward magnitude, probability, and deviation of actually occurring from expected rewards. Less attention has been paid to DA neuron firing and DA release in response to aversive stimuli, and the prediction and Avoidance of punishment. In this review, we first focus on DA changes in response to aversive stimuli as measured by microdialysis and voltammetry followed by the change in electrophysiological signatures by aversive stimuli and fearful events. We subsequently focus on the role of DA and effect of DA manipulations on signaled Avoidance Learning, which consists of Learning the significance of a warning cue through Pavlovian associations and the execution of an instrumental Avoidance response. We present a coherent framework utilizing the data on microdialysis, voltammetry, electrophysiological recording, electrical brain stimulation, and behavioral analysis. We end by outlining current gaps in the literature and proposing future directions aimed at incorporating technical and conceptual progress to understand the involvement of reward circuit on punishment based decisions.
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differential neuromodulation of acquisition and retrieval of Avoidance Learning by the lateral habenula and ventral tegmental area
The Journal of Neuroscience, 2010Co-Authors: Jason Shumake, Anton Ilango, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:Several studies suggest an opponent functional relationship between the lateral habenula (LHb) and the ventral tegmental area (VTA). Previous work has linked LHb activation to the inhibition of dopaminergic neurons during loss of reward, as well as to deficits in escape and Avoidance Learning. We hypothesized that a dopamine signal might underlie the negative reinforcement of Avoidance responses and that LHb activation could block this signal and thereby cause Avoidance deficits. To test this idea, we implanted stimulating electrodes in either the VTA or LHb of gerbils engaged in two-way active Avoidance Learning, a task that shows Learning-associated dopamine changes and that is acquired faster following LHb lesions. We delivered brief electrical brain stimulation whenever the animal performed a correct response, i.e., when the successful Avoidance of foot shock was hypothesized to trigger an intrinsic reward signal. During the acquisition phase, VTA stimulation improved Avoidance performance, while LHb stimulation impaired it. VTA stimulation appeared to improve both acquisition and asymptotic performance of the Avoidance response, as VTA-stimulated animals reached above-normal performance but reverted to normal responding when stimulation was discontinued. The effects of LHb stimulation during Avoidance acquisition were long lasting and persisted even after stimulation was discontinued. However, when given after successful acquisition of Avoidance behavior, LHb stimulation had no effect, indicating that LHb stimulation specifically impaired Avoidance acquisition without affecting memory retrieval or motivation or ability to perform the Avoidance response. These results demonstrate opponent roles of LHb and VTA during acquisition but not during retrieval of Avoidance Learning.
M T Allen - One of the best experts on this subject based on the ideXlab platform.
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Avoidance Learning and classical eyeblink conditioning as model systems to explore a Learning diathesis model of ptsd
Neuroscience & Biobehavioral Reviews, 2019Co-Authors: M T Allen, J D Handy, D P Miller, R J ServatiusAbstract:Abstract Experiencing a trauma is necessary, but not sufficient, for the development of post-traumatic stress disorder (PTSD) in that most individuals who experience a trauma do not go on to develop PTSD. This suggests that identifiable vulnerabilities (i.e., diatheses) exist that increase the risk for the development of PTSD. One such factor is the personality temperament of behavioral inhibition (BI). Organisms that exhibit BI were studied in the context of Avoidance Learning and classical eyeblink conditioning. We present a body of evidence supporting a Learning diathesis model in which behaviorally inhibited organisms exhibit enhanced acquisition and resistance to extinction in these tasks. Vulnerable individuals show Learning-related enhancements when the Learning situation involves some degree of uncertainty. We review the known brain circuitry involved in classical eyeblink conditioning in the context of the Learning diathesis model. Finally, the data reviewed here demonstrate the value of studying vulnerability factors in humans and a rodent model using cerebellar-dependent Learning tasks for understanding the acquisition and endurance of PTSD symptomatology.
Jason Shumake - One of the best experts on this subject based on the ideXlab platform.
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electrical stimulation of lateral habenula during Learning frequency dependent effects on acquisition but not retrieval of a two way active Avoidance response
PLOS ONE, 2013Co-Authors: Anton Ilango, Jason Shumake, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:The lateral habenula (LHb) is an epithalamic structure involved in signaling reward omission and aversive stimuli, and it inhibits dopaminergic neurons during motivated behavior. Less is known about LHb involvement in the acquisition and retrieval of Avoidance Learning. Our previous studies indicated that brief electrical stimulation of the LHb, time-locked to the Avoidance of aversive footshock (presumably during the positive affective “relief” state that occurs when an aversive outcome is averted), inhibited the acquisition of Avoidance Learning. In the present study, we used the same paradigm to investigate different frequencies of LHb stimulation. The effect of 20 Hz vs. 50 Hz vs. 100 Hz stimulation was investigated during two phases, either during acquisition or retrieval in Mongolian gerbils. The results indicated that 50 Hz, but not 20 Hz, was sufficient to produce a long-term impairment in Avoidance Learning, and was somewhat more effective than 100 Hz in this regard. None of the stimulation parameters led to any effects on retrieval of Avoidance Learning, nor did they affect general motor activity. This suggests that, at frequencies in excess of the observed tonic firing rates of LHb neurons (>1–20 Hz), LHb stimulation may serve to interrupt the consolidation of new Avoidance memories. However, these stimulation parameters are not capable of modifying Avoidance memories that have already undergone extensive consolidation.
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the role of dopamine in the context of aversive stimuli with particular reference to acoustically signaled Avoidance Learning
Frontiers in Neuroscience, 2012Co-Authors: Anton Ilango, Jason Shumake, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:Learning from punishment is a powerful means for behavioral adaptation with high relevance for various mechanisms of self-protection. Several studies have explored the contribution of released dopamine (DA) or responses of DA neurons on reward seeking using rewards such as food, water, and sex. Phasic DA signals evoked by rewards or conditioned reward predictors are well documented, as are modulations of these signals by such parameters as reward magnitude, probability, and deviation of actually occurring from expected rewards. Less attention has been paid to DA neuron firing and DA release in response to aversive stimuli, and the prediction and Avoidance of punishment. In this review, we first focus on DA changes in response to aversive stimuli as measured by microdialysis and voltammetry followed by the change in electrophysiological signatures by aversive stimuli and fearful events. We subsequently focus on the role of DA and effect of DA manipulations on signaled Avoidance Learning, which consists of Learning the significance of a warning cue through Pavlovian associations and the execution of an instrumental Avoidance response. We present a coherent framework utilizing the data on microdialysis, voltammetry, electrophysiological recording, electrical brain stimulation, and behavioral analysis. We end by outlining current gaps in the literature and proposing future directions aimed at incorporating technical and conceptual progress to understand the involvement of reward circuit on punishment based decisions.
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differential neuromodulation of acquisition and retrieval of Avoidance Learning by the lateral habenula and ventral tegmental area
The Journal of Neuroscience, 2010Co-Authors: Jason Shumake, Anton Ilango, Wolfram Wetzel, Henning Scheich, Frank W OhlAbstract:Several studies suggest an opponent functional relationship between the lateral habenula (LHb) and the ventral tegmental area (VTA). Previous work has linked LHb activation to the inhibition of dopaminergic neurons during loss of reward, as well as to deficits in escape and Avoidance Learning. We hypothesized that a dopamine signal might underlie the negative reinforcement of Avoidance responses and that LHb activation could block this signal and thereby cause Avoidance deficits. To test this idea, we implanted stimulating electrodes in either the VTA or LHb of gerbils engaged in two-way active Avoidance Learning, a task that shows Learning-associated dopamine changes and that is acquired faster following LHb lesions. We delivered brief electrical brain stimulation whenever the animal performed a correct response, i.e., when the successful Avoidance of foot shock was hypothesized to trigger an intrinsic reward signal. During the acquisition phase, VTA stimulation improved Avoidance performance, while LHb stimulation impaired it. VTA stimulation appeared to improve both acquisition and asymptotic performance of the Avoidance response, as VTA-stimulated animals reached above-normal performance but reverted to normal responding when stimulation was discontinued. The effects of LHb stimulation during Avoidance acquisition were long lasting and persisted even after stimulation was discontinued. However, when given after successful acquisition of Avoidance behavior, LHb stimulation had no effect, indicating that LHb stimulation specifically impaired Avoidance acquisition without affecting memory retrieval or motivation or ability to perform the Avoidance response. These results demonstrate opponent roles of LHb and VTA during acquisition but not during retrieval of Avoidance Learning.
Michael P. Speed - One of the best experts on this subject based on the ideXlab platform.
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A tale of 2 signals: signal mimicry between aposematic species enhances predator Avoidance Learning
Behavioral Ecology, 2010Co-Authors: Hannah M. Rowland, Graeme D. Ruxton, Tom Hoogesteger, Michael P. SpeedAbstract:Mullerian mimicry, where 2 or more unrelated aposematic species resemble one another, is predicted to reduce the per capita mortality of co-mimics by allowing them to share the cost of educating nao ¨ve predators about their unpalatability. However, the specific assumptions and predictions of Muller's theory of shared resemblance have been previously unsupported; some authors have suggested that the benefits of signal similarity are undetectable or at best very small. We demonstrate clearly and un- ambiguously that mimicry between 2 defended forms can provide substantial protection from uneducated predators in the manner proposed originally by Muller. By utilizing prey signals that were designed and demonstrated, to be equally visible, learned with equal facility, and discriminated by our predators, we assessed the effect of the presence of signal mimicry on the survival of a Model species in a ''novel world'' experiment, with wild-caught great tits (Parus major) as predators. We found that the net effect of mimicry was mutualistic, with co-mimics showing increased survivorship through shared predator Learning. Visually distinct prey showed a mortality benefit from coexistence even without signal mimicry as a result of a density-dependent dilution effect. Perfect mimicry provided an added benefit of enhanced predator Avoidance Learning, and our results suggest that the benefits of shared warning signals may be even stronger than Muller originally proposed. Key words: aposematism, Avoidance Learning, evolution, Mullerian mimicry, Parus major. (Behav Ecol)
