Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 12 of 12 for “"Reward Prediction Error"”.
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Altered Decision Behavior of Dopamine Receptor Knock-out Mice in a Free Binary Choice Task
… important role in updating values according to reward prediction error by reinforcement learning theory, since the finding that phasic activity of midbrain dopamine neurons signals the difference between actual and predicted outcomes (reward prediction error). However, the extent and nature of …
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Measuring the Subjective Value of Effort in Behaviour and Midbrain Dopamine Neurons
Reward follows work, but with finite energy, all life must decide what reward is worth the work. Economic theory provides a framework of how rational decision makers optimise this choice: agents should maximise the possible utility (subjective benefit) discounted by the disutility (subjective cost) …
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Reward and prediction errors in Bayesian sensorimotor control
… and promote associative learning by encoding a reward prediction error signal (phasic dopamine). Recent studies on Bayesian sensorimotor control have implicated midbrain dopamine concentration in the integration of prior knowledge and current sensory information. The present behavioral study …
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Synaptic Control of Dopamine as a Driver of Reward Learning
… (VTADA) neurons fire in a manner consistent with Reward Prediction Error, with better-than-expected and worse-than-expected outcomes correlating with bursts and pauses, respectively. Burst and pause firing dynamics are believed to be responsible for driving associative learning, yet interrogating …
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NEURAL BASIS OF PERFORMANCE EVALUATION IN BIRDS
… a key variable in the dopaminergic system, the reward prediction error. Yet most studies of the dopaminergic system have been in situations where an animal is motivated by external rewards, such as food or juice. Does RL apply to learning of complex behavior without immediate external reward? …
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Interactions Between Medical Prefrontal Cortex, Orbitofrontal Cortex and Motor Cortex in Value-based Decision Making
… trials, but neural signals for chosen value and reward prediction error were more prevalent in the OFC. Meanwhile, the AGm conveyed all the signals necessary to update the value of chosen action after the choice outcome was revealed. In contrast, upcoming choice signals arose later and chosen …
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A role for hippocampal and midbrain neural processing in context-dependent spatial memory
… of VTA dopamine neurons is thought to signal an error in the prediction of salient events (particularly rewards) within a given context, it has not been demonstrated that VTA neural activity is modulated by contextual information. Therefore, I recorded the activity of VTA neurons as rats …
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Neuroimaging Investigation of Binge Alcohol Drinking and Opioid Dependency.
… substance users showed blunted dopamine-linked reward prediction error signals in various regions including the bilateral striatum. As hypothesised, binge drinkers showed abnormally decreased striatal dopamine-linked brain activation and blunted reward value encoding in the amygdala-hippocampal …
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Neural basis of multi-attribute economic value: examples from humans and monkeys
… composed of multiple components (e.g. different reward types) has not been systematically studied. In this thesis, I investigated the neural mechanism of two different two-component rewards: (1) fat-sugary milkshake reward in humans using fMRI neuroimaging and (2) probability-magnitude liquid …
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Towards a mechanistic understanding of the neurobiological mechanisms underlying psychosis
… chapter I aimed to elucidate the nature of reward prediction error aberrancies in chronic schizophrenia. There has been some evidence suggesting that schizophrenia is associated with aberrant coding of reward prediction errors during reinforcement learning. However it is unclear whether …
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The role of locus coeruleus norepinephrine in reinforcement learning
… push a lever at a go tone to receive a water reward, and refrain from pushing at a no-go tone to avoid an air-puff punishment, we first explored the role of LC-NE in this behavior. Additionally, we used tones of differing intensity to modulate the uncertainty on a trial by trial basis. We …
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Monoaminergic Signaling in the Human Brain: New Insights
… disease or essential tremors played a social reward task. We observed opponency between dopamine and serotonin to positive prediction errors in patients with essential tremor, but not in those with Parkinson's disease. Moreover, patterns of dopaminergic and serotonergic signaling predicted …