Emotion- and intrusion-based reasoning in Vietnam veterans with and without chronic posttraumatic stress disorder

Patients suffering from anxiety disorders other than posttraumatic stress d isorder (PTSD) interpret anxiety responses themselves as evidence that thre at is impending: "if anxiety, then threat" (Arntz, Rauner, & van den Hout, 1995, Behaviour Research and Therapy, 33, 917-925). This "emotion-based rea soning" (ER) may render a disorder self-perpetuating. Analogous to ER, dang er might also be inferred from the presence of intrusions: "intrusion-based reasoning" (IR). The aims of this study were to test whether ER and IR are involved in chronic PTSD. Vietnam combat veterans with or without PTSD or other anxiety disorders rated perceived danger of brief scenarios in which information about objective danger (danger vs safety) and response (anxiety /intrusions vs non-distressing emotion) was systematically varied. Two seri es were administered: ER-scenarios were non-specific for PTSD and IR-scenar ios were specific for PTSD. Relative to control participants, PTSD patients engaged in both ER and IR: whereas veterans without PTSD inferred the dang er of scenarios from objective stimulus information, veterans with PTSD als o inferred danger from the presence of anxiety or intrusions. Further analy ses showed that these effects were largely mediated by perceived uncontroll ability. (C) 2001 Elsevier Science Ltd. All rights reserved.