| According to the emotional processing theory (Foa & Kozak, 1986), exposure treatment has been associated with a response in physiological and experiential dimensions during in-session activation and habituation. Studies of mediating pathways among these dimensions remain sparse. The goal of this study was to investigate pathways of multidimensional change during repeated exposure sessions for patients with panic disorder and agoraphobia. We further examined whether previously acquired, theoretically distinct coping skills, cognitive restructuring and respiratory control, moderated the changes.;Within-session measures of cardio-respiratory physiology (heart rate, partial pressure of carbon dioxide [pCO2], respiratory rate), cardio-respiratory symptoms, cognitive symptoms, and anxiety were assessed repeatedly during exposure, in addition to between-session measures of panic severity. Analyses revealed condition-independent quadratic changes in cardio-respiratory physiology characterized by initial activation followed by habituation. These findings suggest that the acquisition of the respiratory control coping skills did not dampen the autonomic surge that occurs during exposure. Cardio-respiratory symptoms, cognitive symptoms, and anxiety demonstrated curvilinear changes within sessions, showing initial activation followed by decreases beyond baseline levels at the end of the exposures. Bi-directional mediation was found for changes in cardio-respiratory physiology mediating changes in cardio-respiratory symptoms, cognitive symptoms, and anxiety during exposure. This mediation pattern was stable across sessions and independent of treatment condition. Overall, the results suggest physiological and experiential pathways of change to interact, thus supporting the important role of the physiological dimension in exposure-based treatments of panic disorder. |
