University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 2008 Mindfulness as a Predictor of Posttraumatic Stress Disorder Symptomatology in an Experiential Avoidance Model Brian Lantz Thompson The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Thompson, Brian Lantz, "Mindfulness as a Predictor of Posttraumatic Stress Disorder Symptomatology in an Experiential Avoidance Model" (2008). Graduate Student Theses, Dissertations, & Professional Papers. 665. https://scholarworks.umt.edu/etd/665 This Dissertation is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. MINDFULNESS AS A PREDICTOR OF POSTTRAUMATIC STRESS DISORDER SYMPTOMATOLOGY IN AN EXPERIENTIAL AVOIDANCE MODEL By Brian L. Thompson M.A., Contemplative Psychotherapy, Naropa University, Boulder, CO, 2003 B.A., Psychology, Pennsylvania State University, University Park, PA, 1999 Dissertation presented in partial fulfillment of the requirements for the degree of Doctor of Psychology in Clinical Psychology The University of Montana Missoula, MT Spring 2008 Approved by: Dr. David A. Strobel, Dean Graduate School Jennifer Waltz, Ph.D., Chair Psychology David Schuldberg, Ph.D. Psychology Gyda Swaney, Ph.D. Psychology Bryan Cochran, Ph.D. Psychology Rita Sommers-Flanagan, Ph.D. Educational Leadership and Counseling i i Thompson, Brian, Ph.D., May 2009 Clinical Psychology Mindfulness as a Predictor of Posttraumatic Stress Disorder Symptomatology In an Experiential Avoidance Model Chairperson: Jennifer Waltz, Ph.D. Abstract Content: The purpose of this study was to examine the ability of measures of mindfulness to predict the variance of posttraumatic stress disorder (PTSD) avoidance symptom severity above and beyond measures of experiential avoidance. A sample of 378 introductory psychology students completed questionnaire packets in individuals rooms to insure confidentiality of sensitive material. Based on a pencil-and-paper self-report measure of PTSD symptoms, the sample was divided into 3 groups: PTSD group ( n = 44); trauma-no PTSD ( n = 147); and a control (no trauma) group ( n = 123). A fourth traumatized group was subsequently created consisting of individuals who endorsed a criterion A trauma, but who may or may not meet full PTSD criteria. Experiential avoidance measures of alexithymia and thought suppression were the most robust predictors of PTSD avoidance symptom severity, but mindfulness predicted more individual variance than measures of emotional coping, emotional intelligence, and a general measure of experiential avoidance. Although not as a strong a predictor of PTSD avoidance symptomatology as alexithymia and thought suppression, mindfulness appears to uniquely account for a significant amount of the variance of PTSD avoidance symptom severity. Treatment implications are discussed. ii Acknowledgements I would like to thank my parents for their unconditional support and approval throughout my school and life in general. Perhaps the greatest evidence of their trust in me was their willingness to hold their tongues when I announced that I would be attending a Buddhist- influenced Master’s program. And it is with great relief that I can justifiably say that I have vindicated that trust to some degree in these pages. I would be remiss if I did not thank my advisor, Jennifer Waltz, Ph.D., for her sound advice and guidance throughout my four years at the University of Montana. I’ve found I could always trust her judgment, and that I could take comfort that, when entering into new territory, I was doing so with her stamp of approval. iii Table of Contents Introduction..................................................................................................................................... 1 Mindfulness ................................................................................................................................ 2 Posttraumatic Stress Disorder..................................................................................................... 5 Experiential Avoidance & PTSD................................................................................................ 7 Thought suppression ............................................................................................................... 9 Avoidant coping .................................................................................................................... 12 Emotional intelligence and alexithymia ................................................................................ 13 Mindfulness-Based Treatments ................................................................................................ 16 Mindfulness-Based Stress Reduction .................................................................................... 16 Mindfulness-Based Cognitive Therapy for Depression ........................................................ 18 Dialectical Behavioral Therapy ............................................................................................ 18 Mindfulness-Based Treatment for Trauma Survivors. ............................................................. 19 Mindfulness as a Predictor of Avoidance Symptoms............................................................... 21 Hypotheses................................................................................................................................ 22 Mindfulness, experiential avoidance, and PTSD .................................................................. 22 Method .......................................................................................................................................... 23 Participants................................................................................................................................ 23 Measures ................................................................................................................................... 24 Procedure .................................................................................................................................. 27 Results........................................................................................................................................... 28 Internal Consistency ................................................................................................................. 28 Between Group Differences by Trauma History ...................................................................... 29 iv PTSD, Mindfulness, and Experiential Avoidance.................................................................... 32 Avoidance Symptom Severity, Mindfulness, and Experiential Avoidance in a Traumatized Sample ...................................................................................................................................... 40 Experiential Avoidance and Mindfulness as Predictors of PTSD Status ................................. 49 Discussion..................................................................................................................................... 51 Alexithymia .............................................................................................................................. 53 Thought Suppression ................................................................................................................ 54 The Acceptance and Action Questionnaire .............................................................................. 55 Emotional Intelligence.............................................................................................................. 56 Coping Skills............................................................................................................................. 56 Explaining Posttraumatic Symptoms with Experiential Avoidance......................................... 57 Mindfulness .............................................................................................................................. 59 Self-Compassion....................................................................................................................... 62 Treatment Implications ............................................................................................................. 63 Limitations................................................................................................................................ 64 References..................................................................................................................................... 67 Appendix A................................................................................................................................... 83 v List of Tables Table 1: Demographics of Total and PTSD Samples ……………………………………………24 Table 2: Comparison of Measures between Control, Trauma-no PTSD, and PTSD Groups …...31 Table 3: Cohen’s d Calculated for Measures between Trauma Groups ………………...………32 Table 4: Pearson Product-Moment Correlation Coefficients for PTSD Sample (n=44)….....….34 Table 5a: Hierarchical Regression Analyses