Images of heroin preparation and injection can incite craving and excite brain areas associated with reward-seeking even in stabilized, long-term, methadone-maintained patients, according to Drs. Daniel Langleben, Anna Rose Childress, Charles O'Brien, and colleagues at the Penn-VA Addiction Treatment Research Center at the University of Pennsylvania School of Medicine and McLean Hospital, Harvard University. The research team used functional magnetic resonance imaging to monitor activity in the extended limbic system of 25 patients in long-term methadone maintenance while showing them heroin-related images before and after their daily methadone dose. Subjective heroin craving and limbic reactivity to heroin cues were greater before, as compared with after, the daily methadone medication, but methadone plasma levels were uncorrelated with the brain response. The findings suggest that individuals in methadone maintenance treatment remain responsive to cues that may motivate heroin seeking and relapse, particularly under conditions of high drug expectancy, such as prior to their daily medication dose.
American Journal of Psychiatry 165(3):390-394, 2008. [Full Text]