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Dissociation, Victimisation, and their Associations with Voice Hearing in Young Adults Experiencing First- Episode Psychosis Eleanor Judith Longden Submitted in accordance with the requirements for the degree of Doctor of Philosophy (Ph.D) The University of Leeds Institute of Psychological Sciences and Faculty of Medicine and Health July, 2014 ~ ii ~ The candidate confirms that the work submitted is their own and that appropriate credit has been given where reference has been made to the work of others. This copy has been supplied on the understanding that it is copyright material and that no quotation from the thesis may be published without proper acknowledgement. The right of Eleanor Longden to be identified as Author of this work has been asserted by her in accordance with the Copyright, Designs and Patents Act 1988. © 2014 The University of Leeds and Eleanor Judith Longden ~ iii ~ Acknowledgements Special thanks are owed to the service-users and staff of the Bradford and Airedale Early Intervention in Psychosis Service, who were so generous with their time and input and without whom this thesis would simply not have been possible. Particular gratitude is due to Dr. Anita Brewin, Bob Collins, Fiona Cooke, Ben Johnson, Carl Retnam, and Amy Sanderson; who not only went to wonderful and unexpected lengths to accommodate the research process, but were also an endless sources of assistance, guidance, and good cheer. I am also extremely grateful to my supervisors, Professor Allan House and Dr. Mitch Waterman at the University of Leeds, for their unstinting patience, wisdom, and support. Their respective expertise and insights have guided my development as a researcher, and were absolutely instrumental for improving and honing the thesis at every stage. I would also like to thank my friends and family for their support and encouragement over the years it took to complete the thesis; and my partner Ben, for whose warmth, humour, and solidarity I am constantly grateful. Special thanks also to Dave Kremberg and Lucy Goldsmith for their invaluable input and assistance on how to construct and interpret a forest plot (and to Lucy also for the cakes, coffee, and patient explanation of the difference between binary and stepwise logistic regression!) Acknowledgement is also owing to Julian Turner, both for his personal support and for the fascinating insights he shared into his work supporting psychosis patients with histories of complex trauma. His wisdom has which helped me advance my thinking around the influence of dissociation on voice hearing, and his many kindnesses provided considerable solace thoughout the rigours of the doctoral process. The field of study for psychosis is a dynamic and engaging one that has witnessed seismic conceptual, clinical, and empirical shifts in the past two decades. There are many clinicians, academics, and survivor activists whose work has influenced me; not only in a research capacity, but also as a voice hearer and trauma survivor who spent many painful years struggling to find a framework that could unravel and explain my experiences. Many of these individuals I know personally, others I know only through their writings. Yet while none have been directly involved in the preparation of the thesis, it is fair to say that the work stands on their shoulders. Final acknowledgment is therefore due to the intellectual, clinical, political, and personal contributions of Professor Richard Bentall, Peter Bullimore, Professor Mary Boyle, Professor Pat Bracken, Ron Coleman, Dr. Dirk Corstens, Jacqui Dillon, Dr. Sandra Escher, Dr. Lucy Johnstone, Dr. Simon McCarthy-Jones, Professor Andrew Moskowitz, Professor Tony Morrison, Professor John Read, Professor Marius Romme, Dr. Colin Ross, Professor Phil Thomas, and Rachel Waddingham. ~ iv ~ Abstract Background: It has been proposed that voice hearing, even in the context of psychosis, is associated with high levels of dissociation - especially amongst individuals with a history of childhood abuse. This thesis studies these relationships using more rigorous research methods than have been applied in much existing observational work, and contributes original evidence for understanding the incidence of, and associations between, voice hearing, dissociation, and life adversity (particularly childhood sexual abuse: CSA) in a first-episode psychosis sample. Study 1 and 2: Evaluates current knowledge on associations between (1) voice hearing and dissociation, and (2) voice hearing and CSA using systematic, critical literature review. Both studies found strong associations between key variables, although methodological limitations in the literature preclude assumptions of causal relationships. Study 3: Employs self-report measures and a retrospective case-control design to assess voice hearing, dissociation, psychological distress, and adversity exposure within a pseudo-random sample of voice hearers (n=31) and non-voice hearing controls (n=31). CSA and dissociation were significantly higher amongst case participants. Dissociation retained a significant association with voice hearing when controlling for pre-illness adversity exposures and psychological distress. Study 4: Employs self-report measures and a cross-sectional between-groups design to assess dissociation, distress, and voice phenomenology within a pseudo-random sample of voice hearers with (n=23) and without (n=23) self-reported CSA exposure. CSA severity was associated with higher dissociation. Both groups reported similar voice characteristics, although CSA survivors perceived voices as more omnipotent. Emotional responses to voices showed strongest associations with psychological distress when controlling for dissociation and adversity exposure. Summary: Considerable heterogeneity was apparent for all measures between and within groups of voice hearers and non-voice hearers, and voice hearers with and without CSA exposure. Associations between voice hearing and dissociation remain significant when controlling for adversity exposure and the type of stress, anxiety, and depression that occurs in the more general context of psychosis. However, while dissociation increases the likelihood of voice hearing per se, psychological distress has stronger associations for experiencing voices as negative. The datasets are interpreted within the context of wider clinical/conceptual debates around the role of dissociation, distress, and adverse life events in psychosis, and are used to generate recommendations for both therapeutic intervention and future research. ~ v ~ Table of Contents Acknowledgements……….…………………..………………………………………………iii Abstract…………………………….…………………………………………………………iv Table of Content.……………………..……………...……………………………………..v List of Tables……………………………………………..…………………………………xii List of Figures……………………………………………………………………………….xv Chapter 1 Introduction……………………...…………………………………………17 1.1 Contemporary and Historical Perspectives on Voice Hearing, Psychosis, and Dissociation………………………………………...19 1.2 Voice Hearing, Dissociation, and Traumatic Life Events…………..21 1.3 The Current Research……………………………………………….23 1.3.1 Implications of the current research………………………..26 1.3.2 Research context and epistemological position……………27 1.3.3 Research aims and hypotheses……………………………..29 1.3.4 Structure of the thesis………………………………………30 Chapter 2 Construct Definition……....………………………………………………..32 2.1 Voice Hearing………………………………………………………32 2.1.1 Primary characteristics……………..………………………34 2.1.1.2 Human vocalisation……………………………….34 2.1.1.3 Conscious state…………………………………….35 2.1.1.4 Not induced by organic or state-dependent circumstances……………………………………...36 2.1.2 Secondary features…………………………………………37 2.1.2.1 Form………………………………………………..37 2.1.2.2 Content……………………………………………..40 2.1.3 Impact and appraisals………………………………………44 2.1.3.1 Distress………………………………….…………44 2.1.3.2 Control.…………………………………………….45 2.1.3.3 Beliefs about origin………………………………...46 2.1.4 Challenges and limitations in the literature………………...48 2.1.5 Summary…………………………………………………...51 2.2 Dissociation………………………………………............................51 2.2.1 Historical shifts in definitions of dissociation……………...52 2.2.2 Normal vs. pathological dissociation.……………………...55 2.2.3 Dissociative phenomena and dissociative disorders……….56 ~ vi ~ 2.2.3.1 Depersonalisation disorder………………………...56 2.2.3.2 Dissociative amnesia……………………………….56 2.2.3.3 Dissociative fugue………………………………….58 2.2.3.4 Dissociative identity disorder………………………58 2.2.3.5 Dissociative disorder not otherwise specified……...59 2.2.4 Challenges and limitations in the literature………………...59 2.2.5 Summary…………………………………………………...61 2.3 Trauma……………………………………………………………...62 2.3.1 What constitutes a traumatic event?......................................62 2.3.1.2 Victimisation experiences…………………………64 2.3.1.3 Childhood abuse…………………………………...66 2.3.1.4 Post-childhood trauma…………………………….68 2.3.2 Trauma severity: Consensus vs. contextual views…………68 2.3.2.1 Cumulative trauma………………………………...70 2.3.3 Challenges and limitations in the literature………………...71 2.3.4 Summary…………………………………………………...75 Chapter 3 Study 1: Systematic Literature Review for Evidence of a Causal Association between Voice Hearing and Dissociation…………………...77 3.1 Aims of the Review…………………………………………………77 3.2 Method……………………………………………………………...77 3.2.1 Search procedure…………………………………………...77 3.2.2 Inclusion criteria…………………………………………...78 3.2.3 Exclusion criteria…………………………………………..79 3.2.4 Inferring causality………………………………………….79 3.2.5 Quality assessment…………………………………………80 3.2.6 Analysis strategy…………………………………………...80 3.3 Results………………………………………………………………81