Modulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depression

<p>It has recently been proposed that deficits in reinforcement learning are a core feature of depressive disorders. This thesis aimed to investigate whether transcranial direct current stimulation (tDCS) could be applied to alter these learning processes in healthy adults and individuals with...

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Main Author: Overman, M
Other Authors: O'Shea, J
Format: Thesis
Language:English
Published: 2018
Subjects:
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author Overman, M
author2 O'Shea, J
author_facet O'Shea, J
Overman, M
author_sort Overman, M
collection OXFORD
description <p>It has recently been proposed that deficits in reinforcement learning are a core feature of depressive disorders. This thesis aimed to investigate whether transcranial direct current stimulation (tDCS) could be applied to alter these learning processes in healthy adults and individuals with symptoms of depression. A first study assessed the psychometric properties of a computerised reinforcement learning task, which was the main paradigm used in the tDCS studies. Next, a neurostimulation study was designed to examine the effects of tDCS of the dorsolateral prefrontal cortex (DLPFC) on reinforcement learning parameters in healthy adults. It was found that prefrontal stimulation was associated with faster learning from positive but not negative outcomes when applied during task performance. The subsequent study investigated whether this effect of neurostimulation could be harnessed to augment a cognitive training paradigm aimed to enhance learning from either positive or negative events. No evidence was found that tDCS could boost effects of cognitive training on either reinforcement learning or affective biases in information processing in healthy adults. Finally, a pilot study examined whether tDCS of the DLPFC could affect reward learning in a sample of individuals with subclinical depression. While interpretations of the findings were limited by the study’s small sample size, there were indications that active tDCS might enhance learning rates for both positive and negative outcomes during stimulation in this population. Altogether, this work presents preliminary evidence that non-invasive brain stimulation can transiently alter reinforcement learning processes in healthy adults and subclinical depression. Additional research is needed to examine the potential of this technique as a clinical intervention for depression and related psychiatric disorders.</p>
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spelling oxford-uuid:cc95bb04-8c5a-449d-8d65-657e1d5c08362022-03-27T07:22:58ZModulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depressionThesishttp://purl.org/coar/resource_type/c_db06uuid:cc95bb04-8c5a-449d-8d65-657e1d5c0836clinical neurosciencecomputational psychiatryEnglishORA Deposit2018Overman, MO'Shea, JBrowning, M<p>It has recently been proposed that deficits in reinforcement learning are a core feature of depressive disorders. This thesis aimed to investigate whether transcranial direct current stimulation (tDCS) could be applied to alter these learning processes in healthy adults and individuals with symptoms of depression. A first study assessed the psychometric properties of a computerised reinforcement learning task, which was the main paradigm used in the tDCS studies. Next, a neurostimulation study was designed to examine the effects of tDCS of the dorsolateral prefrontal cortex (DLPFC) on reinforcement learning parameters in healthy adults. It was found that prefrontal stimulation was associated with faster learning from positive but not negative outcomes when applied during task performance. The subsequent study investigated whether this effect of neurostimulation could be harnessed to augment a cognitive training paradigm aimed to enhance learning from either positive or negative events. No evidence was found that tDCS could boost effects of cognitive training on either reinforcement learning or affective biases in information processing in healthy adults. Finally, a pilot study examined whether tDCS of the DLPFC could affect reward learning in a sample of individuals with subclinical depression. While interpretations of the findings were limited by the study’s small sample size, there were indications that active tDCS might enhance learning rates for both positive and negative outcomes during stimulation in this population. Altogether, this work presents preliminary evidence that non-invasive brain stimulation can transiently alter reinforcement learning processes in healthy adults and subclinical depression. Additional research is needed to examine the potential of this technique as a clinical intervention for depression and related psychiatric disorders.</p>
spellingShingle clinical neuroscience
computational psychiatry
Overman, M
Modulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depression
title Modulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depression
title_full Modulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depression
title_fullStr Modulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depression
title_full_unstemmed Modulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depression
title_short Modulating reward learning in healthy adults with transcranial direct current stimulation: Towards a novel treatment for depression
title_sort modulating reward learning in healthy adults with transcranial direct current stimulation towards a novel treatment for depression
topic clinical neuroscience
computational psychiatry
work_keys_str_mv AT overmanm modulatingrewardlearninginhealthyadultswithtranscranialdirectcurrentstimulationtowardsanoveltreatmentfordepression