Sensitization to the psychosis-inducing effects of cocaine compared with measures of cocaine craving and cue reactivity.

A previous study has suggested that sensitization to the psychosis-inducing effects of cocaine may be a marker of vulnerability to relapse in cocaine addiction. In this report, cocaine-dependent subjects participating in a study on naturally occurring and cue-induced cocaine craving were interviewed about prior experience of cocaine-induced psychosis and the degree to which this effect had become more frequent or severe or had occurred at lower cumulative doses. Sensitization to cocaine-induced psychosis was negatively correlated with baseline measures of drug dependence severity and indices of cocaine craving over the preceding 24 hours but not with measures of cocaine cue reactivity.

Quantitative electroencephalographic studies of cue-induced cocaine craving.

Quantitative electroencephalographic (qEEG) profiles were studied in cocaine dependent patients in response to cocaine cue exposure. Using neurometric analytical methods, the spectral power of each primary bandwidth was computed and topographically mapped. Additional measures of cue-reactivity included cocaine craving, anxiety and related subjective ratings, and physiological measures of skin conductance, skin temperature, heart rate, and plasma cortisol and HVA levels. Twenty-four crack cocaine-dependent subjects were tested for their response to tactile, visual and audio cues related to crack cocaine or neutral items. All measures were analyzed for significant difference by comparing cocaine versus neutral cue conditions. An increase in cocaine craving, anxiety and related subjective ratings, elevated plasma cortisol levels, and a decrease in skin temperature, were induced by cocaine cue exposure. Distinct qEEG profiles were found during the paraphernalia handling and video viewing (eyes-open), and guided imagery (eyes-closed), phases of cocaine cue exposure. During paraphernalia handling and video viewing, there was an increase in beta activity accompanied by a drop in delta power in the frontal cortex, and an increase in beta mean frequency in the occipital cortex. In contrast, during guided imagery there was an increase in theta and delta power in the frontal cortex, and an increase in beta power in the occipital cortex. Correlation analyses revealed that cue-induced anxiety during paraphernalia handling and video viewing was associated with reduced high frequency and enhanced low frequency EEG activity. These findings demonstrated that EEG activation during cue-induced cocaine craving may be topographically mapped and subsequently analyzed for functional relevance.