The primary goal of this proposal is to systematically examine the psychological and physiological responses of narcotic addicts to stimuli previously associated with drug-taking behavior. Drug addicts and non-addicted control subjects are shown stimuli reminiscent of drug-taking behavior in the form of a videotape (VT) and an assortment of drug paraphernalia. Prior to the stimulus presentation, measures of mood state and craving are taken. During the presentation, physiological measures of heart rate, skin resistance, skin temperature and respiration are monitored along with subjective level of craving. Subsequent to the VT, the psychological measures are taken and compared to the pre-stimulus scores. The same measures are also taken before, during and after viewing control films, including a non-drug-related, emotionally neutral film and non-drug-related stress film as controls for general arousal and stress factors. Goals of our study include an assessment of the stability of drug addicts' response systems. Initial results indicate that a longer period of time might be necessary for habituation to the experimental set-up, as compared with controls. In subsequent studies we will attempt to answer the following questions: (1) Are the subjects' responses specific to drug-related stimuli? (2) Are the responses limited to addicts, i.e., those with conditioning experiences - or at least, is the response topography different from those control groups? (3) Are the responses greater in subjects who have been addicted longer - thus having a longer conditioning history? and (4) Are the conditioned responses a function of drive or current levels of opiate use? This project is an attempt to expand on prior studies by the applicants demonstrating psychological and physiological conditioned responses to a VT. The present design should accomplish this in a systematic manner. The use of appropriate control subjects, precise presentation of stimuli and additional physiological measures will allow us to draw firm conclusions for our results.