University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 8-2017 Exploring a multifactorial, clinical model of thought disorder : application of a dimensional, transdiagnostic approach. Mara Ann Hart University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Part of the Clinical Psychology Commons, Mental Disorders Commons, Psychiatric and Mental Health Commons, and the Psychological Phenomena and Processes Commons Recommended Citation Hart, Mara Ann, "Exploring a multifactorial, clinical model of thought disorder : application of a dimensional, transdiagnostic approach." (2017). Electronic Theses and Dissertations. Paper 2740. https://doi.org/10.18297/etd/2740 This Doctoral Dissertation is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. EXPLORING A MULTIFACTORIAL, CLINICAL MODEL OF THOUGHT DISORDER: APPLICATION OF A DIMENSIONAL, TRANSDIAGNOSTIC APPROACH By Mara Ann Hart B.A., Loyola College in Maryland, 2006 M.S., Loyola College in Maryland, 2009 A Dissertation Submitted to the Faculty of the College of Arts and Sciences of the University of Louisville In Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy in Clinical Psychology Department of Psychological and Brain Sciences University of Louisville Louisville, KY August 2017 Copyright 2016 by Mara Ann Hart All rights reserved. EXPLORING A MULTIFACTORIAL, CLINICAL MODEL OF THOUGHT DISORDER: APPLICATION OF A DIMENSIONAL, TRANSDIAGNOSTIC APPROACH By Mara Ann Hart B.A., Loyola College in Maryland, 2006 M.S., Loyola College in Maryland, 2009 A Dissertation Approved on: July 29, 2016 by the Following Dissertation Committee Dissertation Director Richard Lewine Benjamin Mast Janet Woodruff-Borden Suzanne Meeks Tracy Eells ii I cannot experience your experience. You cannot experience my experience. We are both invisible men. – R.D. Laing, The Politics of Experience iii ACKNOWLEDGEMENTS I was introduced to thought disorder on my first day of graduate school; so began a five- year journey through which this dissertation evolved. Many people provided help and support along the way. Above all, I am grateful for Rich Lewine, an incredible mentor, researcher, and clinician, who helped me see that grappling with complexity is more important than searching for answers. I am deeply grateful for Debbie Levy, who shared this remarkable dataset with me, without which, this dissertation would not have been possible. Thank you to Morgan Martin, who helped me code thousands of lines of data… twice, somehow staying interested and enthusiastic throughout the process. And to my lab mates, Rachel and Cat, who were there from the beginning and made this journey a whole lot more fun. I would also like to thank to mom and grandma, my cheerleaders, who still can’t quite figure out what this dissertation is about, but have had unyielding interest and confidence in me nonetheless. And to Brian and Olive who have been limitlessly patient and supportive. iv ABSTRACT EXPLORING A MULTIFACTORIAL, CLINICAL MODEL OF THOUGHT DISORDER: APPLICATION OF A DIMENSIONAL, TRANSDIAGNOSTIC APPROACH Mara A. Hart July 29, 2016 Background: Bleuler saw thought disorder as the core defining feature of psychotic phenomena, reflective of the “splitting of the psychic functions” that occurred when, in the process of thinking, one’s ideas and feelings disconnect, becoming fragmented and competing functions. Unfortunately, interest in thought disorder as the conceptual core of psychosis was lost with rise of the modern DSM system, paralleling the shift towards a more simplistic, categorical way of defining psychiatric disorders. Aims: This study examined thought disorder from a dimensional perspective, with the aim of disentangling qualitative heterogeneity and diverse sources of influence. Analyses were based on a large, transdiagnostic sample (n = 322), including individuals diagnosed with schizophrenia, schizoaffective disorder, and bipolar disorder. Structural equation modeling was used to estimate the unique and combined effects of family psychiatric history, age-at-onset, affective state, and sex on two dimensions of thought disorder, namely idiosyncratic thinking and combinatory thinking. We also explored the utility of categorical (i.e. DSM) diagnosis, by estimating the relative proportion of variance it accounted for within the model. v Results: The overall model accounted for 11% of variance in idiosyncratic thinking and 3% of the variance in combinatory thinking. Negative affect was the strongest predictor of idiosyncratic thinking (r = .27), although this effect was significantly more robust in those with a family history of psychosis (r = .37) compared to those without (r = .02). DSM diagnosis was a significant predictor of IV, explaining 7% of unique variance when entered into the full model compared to 9% of the variance when estimated independently, which suggests that the portion of variance explained by diagnosis was largely independent of other predictors in the model. Discussion: The pattern of associations among family psychiatric history, age-at- onset, and negative affect that predicted idiosyncratic thinking are suggestive of a developmental process. This hypothesis is explored in the context of previous research. The broad implications of this research on the classification and study of psychosis is also discussed. vi TABLE OF CONTENTS INTRODUCTION ........................................................................................................................... 1 Limitations of DSM Classification .............................................................................................. 4 Dimensional Measurement: Capturing the Psychosis Continuum .............................................. 8 Thought Disorder: Conceptualization and Assessment ............................................................... 9 Diagnosis-Based Study of Thought Disorder. ........................................................................... 15 The Significance of Affective Experience in the Etiology of Thought Disorder ...................... 20 Moderators and Correlates of Thought Disorder ....................................................................... 25 Demographic Factors. ........................................................................................................... 25 Clinical Factors. .................................................................................................................... 27 Summary ............................................................................................................................... 30 Study Purpose and Hypotheses ................................................................................................. 31 Overview of Proposed Model ............................................................................................... 32 Primary Research Questions ................................................................................................. 34 METHODS .................................................................................................................................... 36 Description of Dataset ............................................................................................................... 36 Measures .................................................................................................................................... 37 Thought Disorder. ................................................................................................................. 37 Affective State. ...................................................................................................................... 39 Family Psychiatric History. ................................................................................................... 41 Analysis Plan ............................................................................................................................. 47 Specified Model. ................................................................................................................... 47 Analysis Decisions ................................................................................................................ 48 Model Fit Criteria. ................................................................................................................. 48 Sample Size and Statistical Power. ....................................................................................... 50 Preliminary Analyses. ........................................................................................................... 50 Missing Values and Outliers ................................................................................................. 53 Primary Analyses ....................................................................................................................... 62 Measurement Model .............................................................................................................. 62 Structural Model .......................................................................................................................