title: Harm expectancy violation during exposure therapy for posttraumatic stress disorder.
abstract: Exposure therapy has proven efficacy in the treatment of posttraumatic stress disorder (PTSD). Emotional processing theory proposes that fear habituation is a central mechanism in symptom reduction, but the empirical evidence supporting this is mixed. Recently it has been proposed that violation of harm expectancies is a crucial mechanism of action in exposure therapy. But to date, changes in harm expectancies have not been examined during exposure therapy in PTSD. The goal of the current study was to examine harm expectancy violation as mechanism of change in exposure therapy for posttraumatic stress disorder (PTSD). Patients (N=50, 44 female) with a primary diagnosis of chronic PTSD received intensive exposure therapy. Harm expectancies, harm experiences and subjective units of distress (SUDs) were assessed at each imaginal exposure session, and PTSD symptoms were assessed pre- and posttreatment with the Clinician Administered PTSD Scale (CAPS). Results showed that harm expectancies were violated within and strongly declined in-between exposure therapy sessions. However, expectancy violation was not related to PTSD symptom change. Fear habituation measures were moderately related to PTSD symptom reductions. In line with theory, exposure therapy promotes expectancy violation in PTSD patients, but this is not related to exposure therapy outcome. More work is warranted to investigate mechanisms of change during exposure therapy in PTSD.
authors.affiliation: Institute of Psychology, Leiden University, The Netherlands; Center for Anxiety Disorders Overwaal, Institution for Integrated Mental Health Care Pro Persona, Nijmegen, The Netherlands. Electronic address: r.a.de.kleine@fsw.leidenuniv.nl.
authors.forename: Rianne A
authors.initials: RA
authors.lastname: de Kleine
authors.affiliation: Center for Anxiety Disorders Overwaal, Institution for Integrated Mental Health Care Pro Persona, Nijmegen, The Netherlands; Radboud University, Behavioural Science Institute, NijCare, Nijmegen, The Netherlands.
authors.forename: Lotte
authors.initials: L
authors.lastname: Hendriks
authors.affiliation: Radboud University, Behavioural Science Institute, NijCare, Nijmegen, The Netherlands.
authors.forename: Eni S
authors.initials: ES
authors.lastname: Becker
authors.affiliation: Bureau Beta, Nijmegen, The Netherlands.
authors.forename: Theo G
authors.initials: TG
authors.lastname: Broekman
authors.affiliation: Center for Anxiety Disorders Overwaal, Institution for Integrated Mental Health Care Pro Persona, Nijmegen, The Netherlands; Radboud University, Behavioural Science Institute, NijCare, Nijmegen, The Netherlands.
authors.forename: Agnes
authors.initials: A
authors.lastname: van Minnen
mesh_terms: D000328:Adult; D002908:Chronic Disease; D004644:Emotions; D005239:Fear; D005260:Female; D006185:Habituation, Psychophysiologic / Q000502:physiology; D006801:Humans; D007171:Implosive Therapy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D013313:Stress Disorders, Post-Traumatic / Q000523:psychology / Q000628:therapy*; D016896:Treatment Outcome
keywords: Expectancy violation; Exposure therapy; Fear habituation; Mechanisms of change; PTSD