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study to examine the way in which dependence changes over time if indeed it does; the question of whether cognitive or behavioural control is acting on an essentially unchanged state of dependence (Logan 1993) or whether the state itself changes (Rankin and Hodgson 1976) will be addressed in the present study.
The cue exposure work of Rankin and Hodgson (1976) is based upon the assertion that the dependent state will be reduced when the conditioned response is weakened through the assertion of cognitive control. In an experiment designed “to break up the continuation of drinking rather than the initiation of drinking” (Rankin and Hodgson 1976 p. 623), the investigators sought to modify the expectation of withdrawal symptoms created by the consumption of a few drinks in an individual diagnosed as alcohol dependent and thus to extinguish the perceived compulsion to continue drinking. These researchers demonstrated the way in which the craving response to cues for drinking could be extinguished in a subsequent cue exposure trial involving actual and imagined exposure to alcoholic beverages (Rankin et al. 1983). O’Brien et al. (1992) have shown that cocaine use can be reduced by a passive extinction technique used in an eight week outpatient treatment programme. Patients were repeatedly exposed to “cocaine reminders” while in the safety of the hospital setting and without these conditioned cues being accompanied by the consumption of cocaine.
Childress and her colleagues (Childress et al. 1988a, 1988b), in a series of studies in Philadelphia showed that drug using behaviour could be extinguished by cue exposure but that different results would be obtained depending upon whether the behaviour was cued by craving (drug anticipation) or by subjective feelings of withdrawal. Withdrawal symptoms that had been environmentally conditioned were much harder to extinguish than feelings of craving that had been environmentally conditioned. These findings are suggestive of the work of Russell et al. (1974) when he showed that at higher levels of severity, smoking is more often conditioned by physiological cues than by social and pharmacological cues.
Belief in the possibility of reducing dependence on addictive substances is based in classical and operant conditioning theory combined with an understanding of cognitive mediating factors. Cue exposure work in clinical settings has yielded disappointing results to date but the reasons proposed are the difficulty in replicating real life conditions in the clinical situation with subsequent problems of generalisability, the sheer number of cues that have been conditioned by the time an individual reaches a treatment setting, the difficulty in identifying these and delivering effective treatment (Dawe and Powell 1995). This, however does not diminish the significance of repeated findings that there is a variety of ways in which dependence changes as well as cases where it does
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