A psychophysiological investigation of emotion regulation in chronic severe posttraumatic stress disorder.

There have been few direct examinations of the volitional control of emotional responses to provocative stimuli in PTSD. To address this gap, an emotion regulation task was administered to 27 Operation Enduring Freedom/Operation Iraqi Freedom combat veterans and 23 healthy controls. Neutral and aversive photographs were presented to participants who did or did not employ emotion regulation strategies. Objective indices included corrugator electromyogram, the late positive potential, and the electrocardiogram. On uninstructed trials, participants with PTSD exhibited blunted cardiac reactivity rather than the exaggerated cardioacceleratory responses seen in trauma cue reactivity studies. On interleaved regulation trials, no measure evidenced group differences in voluntary emotion regulation. Persons with PTSD may not differ from normals in their capacity to voluntarily regulate normative emotional responses to provocative stimuli in the laboratory, though they may nevertheless respond differentially on uninstructed trials and endorse symptoms of dyscontrol pathognomonic of the disorder outside of the laboratory.