 Relapse to drug abuse often happens in the presence of stimuli that are associated with previous drug-use, and drug-taking behavior appears to be partly controlled by such cues. While some theories postulate that such facilitation is mediated by cue-induced craving states, others hypothesize that the underlying processes are highly automatized and can happen without conscious control or even awareness. One way to approach psychological mechanisms of cue reactivity is to measure disruption of ongoing mental activity by drug-related material in dependent individuals while manipulating the degree to which cognitive evaluative processes can unfold. Craving measurement under these conditions can elucidate its relationship with automatic processing versus conscious evaluation of drug cues. Autonomic and neural correlates can be identified by concomitant psychophysiological and fMRI recording. Results from these studies will shed light on the role of spontaneous automatic reactions versus cognitive evaluation for different measures of cue reactivity. By helping to elucidate the psychological mechanisms and neurobiological basis of drug-cue reactivity in dependent individuals, this may have substantial implications for the understanding of mechanisms and treatment of drug dependence. Thus, while there are no direct benefits to subjects participating in these experiments, the results may benefit the health of society. MRI-related risks to subjects injury from metal implants, claustrophobia, temporary deafness due to the loud banging noises will be minimized by prescreening and providing earplugs. Drug-related cues may induce acute craving; subjects will be dismissed only after craving levels have returned to baseline. 