Affect Without Recollection in Posttraumatic Stress Disorder
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Affect without Recollection in Posttraumatic Stress Disorder Elizabeth Woodward DClinPsy thesis (Volume 1) 2020 University College London 1 Thesis Declaration form I confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. Signature Name: Elizabeth Woodward Date: 17.07.2020 2 Overview Re-experiencing symptoms in posttraumatic stress disorder (PTSD) include an affective or physiological response to a reminder of the trauma, not identifiable by the patient as a trauma memory. This has been termed ‘Affect without recollection’ (AWR; Ehlers & Clark, 2000). AWR has been anecdotally reported, but never formally defined or investigated. Part 1 of the thesis provides a conceptual introduction to AWR in PTSD. Theoretical frameworks of reexperiencing in PTSD are reviewed, including cognitive (Ehlers & Clark, 2000) and neurobiological (Brewin, Dalgleish, & Joseph, 1996; Brewin, Gregory, Lipton, & Burgess, 2010) models of PTSD. From this, a possible definition of AWR and its theoretical underpinnings are proposed. Part 2 of the thesis presents a novel empirical study of AWR, designed to investigate four key research questions: 1) Does affect without recollection exist in PTSD?; 2) What is the nature (phenomenology) of affect without recollection? 3) What predicts affect without recollection in PTSD? 4) Is affect without recollection improved with PTSD treatment? The results showed that AWR exists and is associated with cognitive behavioural responses. Cognitive processes such as dissociation, unhelpful response to intrusions, and negative appraisals predicted AWR, which was improved with PTSD treatment. The results have clinical and theoretical implications for understanding and treating reexperiencing symptoms in PTSD. 3 Impact Statement The results of this thesis could be of use both academically and clinically. There has been a call from researchers in the field for more studies focused on understanding reexperiencing symptoms in posttraumatic stress disorder (PTSD), which have been termed the hallmark of the disorder. Reexperiencing symptoms are still relatively poorly understood, and yet have a significant impact on the lives of people with PTSD, and have been shown to predict and maintain PTSD symptoms (Michael, Ehlers, Halligan, & Clark, 2005). This thesis explored a previously proposed, but never formally defined or investigated, form of reexperiencing termed affect without recollection (Ehlers & Clark, 2000). Affect without recollection is the experience of an emotional or physiological reaction from a traumatic event that is not recognised by the individual as a trauma memory and can be a very confusing and frightening experience. Although reported anecdotally by patients, prior to this thesis it had not been measured and therefore it was unknown whether it existed, what its consequences were, and whether current PTSD treatments are effective in resolving this symptom. The empirical study conducted as part of this thesis provided the first evidence of the existence of AWR, its predictive factors, its consequences for the individual, and the effects of PTSD treatment. The results have the potential for significant clinical impact, including helping clinicians to identify, understand and treat this symptom. It may also have implications for individual sufferers to understand their experiences after a traumatic event. Academically, it contributes to understanding the impact of trauma and PTSD on memory. Methodologically, it adds to the body of literature on the usefulness of ambulatory self-report measures on understanding the daily experiences of people suffering from mental health conditions. It demonstrated the use of smartphone applications for assessing PTSD symptoms over time, which was found to be highly 4 acceptable by participants (reflected in the high completion rates). Finally, it presents modelling techniques which may be useful for the analysis of ecological momentary assessment data in a clinically meaningful way. In sum, it is hoped that the results of this thesis will have implications both clinically and academically. 5 Table of Contents Thesis Declaration form .............................................................................................. 2 Overview ....................................................................................................................... 3 Impact Statement ......................................................................................................... 4 Table of Contents ......................................................................................................... 6 Table of Figures ............................................................................................................ 8 Table of Tables ............................................................................................................. 8 Acknowledgments ........................................................................................................ 9 Part 1: Conceptual Introduction .............................................................................. 10 Abstract ................................................................................................................... 11 Introduction ............................................................................................................ 12 Posttraumatic Stress Disorder .............................................................................. 13 Defining Trauma .................................................................................................. 13 Posttraumatic stress disorder: definition and epidemiology ................................ 14 Cognitive model of PTSD .................................................................................... 16 Memory in PTSD ................................................................................................... 18 Memory in PTSD ................................................................................................. 19 Reexperiencing symptoms ..................................................................................... 21 Defining reexperiencing ....................................................................................... 21 Specificity of reexperiencing to PTSD ................................................................ 23 Mechanisms underpinning reexperiencing in PTSD ........................................... 26 Cognitive models of reexperiencing in PTSD ................................................. 27 Neurobiological models of reexperiencing in PTSD ....................................... 35 Affect without recollection .................................................................................... 39 Defining affect without recollection .................................................................... 40 Evidence of affect without recollection ............................................................... 41 Possible mechanisms underpinning affect without recollection .......................... 42 Disjointed from the autobiographical memory base ........................................ 42 Priming and associative learning ..................................................................... 43 Appraisals and coping strategies ...................................................................... 44 Dissociation ...................................................................................................... 45 Summary and aims of the thesis ........................................................................... 46 Summary .............................................................................................................. 46 Theoretical predictions ......................................................................................... 47 6 Aims of the thesis ................................................................................................. 48 References ............................................................................................................... 50 Part 2: Empirical Paper ............................................................................................ 57 Abstract ................................................................................................................... 58 Introduction ............................................................................................................ 59 Method .................................................................................................................... 63 Results ..................................................................................................................... 75 Discussion ................................................................................................................ 90 References ............................................................................................................. 104 Part 3: Critical appraisal ......................................................................................... 109 Introduction ........................................................................................................ 110 Reflections on selection of subject area ............................................................. 110 Reflections on conceptual introduction ............................................................. 111 Establishing research questions ........................................................................