Brain imaging correlates of cue-induced cocaine craving

Cocaine patients commonly report that cues reminiscent of cocaine can trigger profound desire for the drug, but the brain correlates of this state are just beginning to be studied. Responses during cue-induced cocaine craving (increased arousal, heart palpitations, light-headedness, ear-ringing, chest-tightness, a cocaine ‘taste’ in back of the throat, and even mild euphoria) are often very similar to the effects of actual cocaine, suggesting possible overlap of the brain substrates involved. The mesolimbic dopamine system is thought to mediate many of cocaineʹs important pharmacologic effects. We measured brain activity as reflected by regional cerebral blood flow (rCBF) in limbic and in other brain systems during cue-induced craving. rCBF was imaged in abstinent cocaine patients and in matched cocaine-naive control subjects during exposure to videos of both non-drug and cocaine-related scenes. Imaging of rCBF was accomplished with PET (Positron Emission Tomography), using radioactively-labeled (15O) water as the flow tracer. PET scans for each subject were co-registered with a magnetic resonance image to permit anatomical localization of radioactivity. Cocaine patients experienced craving and showed reliable rCBF increases in the cingulate cortex and temporal pole during the cocaine video, as compared to the non-drug video. Systematic activation did not occur in non-limbic regions. Control subjects did not experience craving, and did not show rCBF increases in these regions in response to either video type. These results suggest that temporo-limbic activation may be one component of cue-induced drug craving.