Eating disorders and compulsivity: neural, computational, and psychopharmacological approaches

<p>This DPhil thesis takes the transdiagnostic construct of compulsivity as a basis for investigation into eating disorders, which are severe psychiatric disorders with high mortality rates.</p> <p>This thesis includes three experimental studies (discussed in Chapters 3 to 5), whic...

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Main Author: Pike, A
Other Authors: Cowen, P
Format: Thesis
Language:English
Published: 2018
Subjects:
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author Pike, A
author2 Cowen, P
author_facet Cowen, P
Pike, A
author_sort Pike, A
collection OXFORD
description <p>This DPhil thesis takes the transdiagnostic construct of compulsivity as a basis for investigation into eating disorders, which are severe psychiatric disorders with high mortality rates.</p> <p>This thesis includes three experimental studies (discussed in Chapters 3 to 5), which investigate different aspects of eating disorders and compulsivity.</p> <p>The first experimental study (Chapter 3) is a multimodal magnetic resonance imaging study, in which the neural basis of compulsivity was investigated in participants who had recovered from anorexia nervosa and control participants. We used a task with functional magnetic resonance imaging which incorporated key elements of compulsivity, performed a resting-state analysis with frontostriatal seeds, and analysed glutamate levels using magnetic resonance spectroscopy. We neither found evidence of the hypothesised frontostriatal differences, nor of a difference in glutamate levels in participants, but did find parietal differences in both the resting-state and task-based analyses.</p> <p>The next study, discussed in Chapter 4, aimed to investigate adaptive learning in eating disorders. We predicted that participants in two clinically-relevant groups (those who had recovered from anorexia nervosa, and those who had elevated eating disorder symptoms) would show diminished adaptation of their learning rates in a task which manipulated environmental volatility, and that this would correspond to a reduction in pupil dilation to volatile outcomes in these groups compared to control participants. However, we found elevated adaptation of learning rates in those who had recovered from anorexia nervosa, which may be attributed to heightened learning rates in this group in particular in the first block. </p> <p>The final experimental study is discussed in Chapter 5, and investigated whether a dietary supplement, N-acetylcysteine, would improve performance of those with elevated eating disorder symptoms on tasks which measure compulsive and impulsive responding. However, this did not seem to be the case, though N-acetylcysteine was well-tolerated. </p>
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spelling oxford-uuid:7e94fa3c-8a20-4211-89fc-33287e4568422022-03-26T21:10:58ZEating disorders and compulsivity: neural, computational, and psychopharmacological approachesThesishttp://purl.org/coar/resource_type/c_db06uuid:7e94fa3c-8a20-4211-89fc-33287e456842PsychiatryEnglishORA Deposit2018Pike, ACowen, PPark, R<p>This DPhil thesis takes the transdiagnostic construct of compulsivity as a basis for investigation into eating disorders, which are severe psychiatric disorders with high mortality rates.</p> <p>This thesis includes three experimental studies (discussed in Chapters 3 to 5), which investigate different aspects of eating disorders and compulsivity.</p> <p>The first experimental study (Chapter 3) is a multimodal magnetic resonance imaging study, in which the neural basis of compulsivity was investigated in participants who had recovered from anorexia nervosa and control participants. We used a task with functional magnetic resonance imaging which incorporated key elements of compulsivity, performed a resting-state analysis with frontostriatal seeds, and analysed glutamate levels using magnetic resonance spectroscopy. We neither found evidence of the hypothesised frontostriatal differences, nor of a difference in glutamate levels in participants, but did find parietal differences in both the resting-state and task-based analyses.</p> <p>The next study, discussed in Chapter 4, aimed to investigate adaptive learning in eating disorders. We predicted that participants in two clinically-relevant groups (those who had recovered from anorexia nervosa, and those who had elevated eating disorder symptoms) would show diminished adaptation of their learning rates in a task which manipulated environmental volatility, and that this would correspond to a reduction in pupil dilation to volatile outcomes in these groups compared to control participants. However, we found elevated adaptation of learning rates in those who had recovered from anorexia nervosa, which may be attributed to heightened learning rates in this group in particular in the first block. </p> <p>The final experimental study is discussed in Chapter 5, and investigated whether a dietary supplement, N-acetylcysteine, would improve performance of those with elevated eating disorder symptoms on tasks which measure compulsive and impulsive responding. However, this did not seem to be the case, though N-acetylcysteine was well-tolerated. </p>
spellingShingle Psychiatry
Pike, A
Eating disorders and compulsivity: neural, computational, and psychopharmacological approaches
title Eating disorders and compulsivity: neural, computational, and psychopharmacological approaches
title_full Eating disorders and compulsivity: neural, computational, and psychopharmacological approaches
title_fullStr Eating disorders and compulsivity: neural, computational, and psychopharmacological approaches
title_full_unstemmed Eating disorders and compulsivity: neural, computational, and psychopharmacological approaches
title_short Eating disorders and compulsivity: neural, computational, and psychopharmacological approaches
title_sort eating disorders and compulsivity neural computational and psychopharmacological approaches
topic Psychiatry
work_keys_str_mv AT pikea eatingdisordersandcompulsivityneuralcomputationalandpsychopharmacologicalapproaches