Effects of exposure to heroin-related cues in detoxified persons: Extinction of hyperalgesic conditioned responses?

The goal of this study was to demostrate on detoxified addicted persons to heroin (8 males and 8 females) that hyperalgesic conditioned responses (CRs), as responses of the conditioned abstinence syndrome could be extinguished through repeated exposure to the conditioned stimuli (CSs) which elicit them. Subjects were exposed during 45 days, once a day, to a sequence of four slides displaying CSs related to heroin. In the extinction phase, every five days of exposure in presence of the electric shock administered after the CSs, responses of heart rate, electrodermic activity (conductance), desire for heroin, and subjective abstinence were evaluated. In the follow-up phase the same responses were evaluated in the same way as in the extinction phase, but now every 15 days during 45. Results showed that the value of the evaluated responses experimented a lineal decrement along the recorded day in the extinction phase (p<0.01) and that the values of responses obtained during recorded days in the follow-up phase were always significantly lower than most of those recorded in the extinction (p<0.01).