PSYCHOPHYSIOLOGICAL ASSESSMENT OF MENTAL-IMAGERY OF STRESSFUL EVENTS IN ISRAELI CIVILIAN POSTTRAUMATIC-STRESS-DISORDER PATIENTS

This study explored the physiological responses of posttraumatic stres s disorder (PTSD) patients to reminders of a stressful event that had preceded the onset of their illness and was not related to its cause: the SCUD missile alarms of the Gulf War. A mental-imagery technique us ed in previous studies of PTSD was used. Three 30-second audiotapes we re presented to each subject, including (1) the Gulf War's missile ala rm, (2) a radio announcement of a terrorist attack, and (3) a standard ized relaxing scene. Subjects were instructed to imagine each event as vividly as possible while heart rate (HR), skin conductance (SC), and left lateral frontalis electromyogram (EMG) responses were measured. The responses of 12 outpatients with PTSD were compared with those of panic disorder patients (n = 11), survivors of traumatic events who ha d not developed PTSD (n = 9), and mentally healthy subjects with no li fetime history of major trauma (n = 19). Multivariate analysis of vari ance (MANOVA) for the three physiological measures showed a significan t group difference during imagery of the Gulf War alarm, with PTSD sub jects showing higher SC and EMG responses than the others. The differe nces remained significant when age, level of distress during the war, and concurrent anxiety were controlled for. There were no group differ ences in responses to the other stimuli. We conclude that, PTSD patien ts may either acquire and maintain prolonged conditioned responses to various stressors during their life span or become sensitized to remin ders of past traumata following the onset of their illness. Heightened conditionability may be expressed before the trauma in subjects who a re liable to develop PTSD. Copyright (C) 1997 by W.B. Saunders Company .