EFFECTS OF INTRANASAL VASOPRESSIN AND OXYTOCIN ON PHYSIOLOGICAL RESPONDING DURING PERSONAL COMBAT IMAGERY IN VIETNAM VETERANS WITH POSTTRAUMATIC-STRESS-DISORDER

This study measured heart rate, skin conductance, and lateral frontali s electromyographic (EMG) responses in 43 male Vietnam veterans with p osttraumatic stress disorder during personal combat imagery. In a doub le-blind research design, subjects were randomly assigned to receive i ntranasal arginine vasopressin (20 IU), placebo, or oxytocin (20 IU) a n hour before the experiment. The group order of physiologic respondin g was as predicted: vasopressin > placebo > oxytocin. The most specifi c effect was exerted by vasopressin on EMG responses. This drug effect was not accounted for by nonspecific changes in responsiveness. Resul ts are consistent with enhancing and inhibiting effects on memory retr ieval and conditioned responding of vasopressin and oxytocin, respecti vely.