Psychophysiological response patterns in panic disorder.

To determine whether panic disorder patients exhibit physiological hyperarousal during rest or during mild, non-panic-inducing stress, 18 patients who experienced frequent panic attacks were compared with nonanxious controls on a battery of physiological assessments. During baseline, patients with panic disorder exhibited higher forehead electromyographic activity, higher systolic blood pressure and higher heart rates than non-anxious volunteers. During psychological stress, heart rate and systolic blood pressure rose more in patients with panic disorder than in nonanxious controls. The skin conductance response, however, was greater and more variable in the nonanxious controls. The results suggest that panic disorder patients with frequent panic attacks exhibit heightened cardiovascular arousal and decreased electrodermal flexibility than nonanxious people, even in nonthreatening situations.