Effect of incentives on retention in an outpatient treatment for cocaine addicts

The high drop-out rate in treatment programs is one of the most important problems in the area of drug addictions. This study evaluated the effect of the use of incentives on retention in an outpatient program for cocaine addicts. The effect of individual variables on program drop-out was also analysed. Participants were 66 subjects who were randomly assigned to one of three treatment groups: standard treatment, treatment with incentives I, and treatment with incentives II. The patients of these two groups received incentives contingent on cocaine abstinence with two different magnitudes. Retention rate at six months was 35% in the standard treatment, 78.6% in the treatment with incentives I, and 53.3% in the treatment with incentives II. The global prognostic capacity of the individual variables (sociodemographic, history and consumption pattern, psychopathological variables, and EuropASI scores) was 85.7%, with the psychopathological variables being more closely related to retention. These results suggest that the use of incentives may be an effective strategy to improve retention in outpatient treatments for cocaine addiction.     

Effect of retention interval on the simultaneous cognate-noncognate and remember-know mirror effects

Recognition memory for Spanish-Catalan cognate and noncognate words was tested at retention intervals of 30 minutes, 3 days, and 7 days using a remember/know response procedure. We observed a clear mirror effect for the cognate-noncognate stimulus class and a remember-know response categorisation at the immediate retention interval. However, the cognate and noncognate mirror was still observed at 3 and 7 days, whereas the remember-know mirror disappeared at both retention intervals. Also, we ran a repeated testing condition to be able to carry out a sequential item analysis and observe the fate of the original remember and know responses 3 or 7 days later. The analysis supported the idea that there was a loss of contextual information that was at the root of the disappearance of the remember-know mirror effect. These results provide support to the idea that it is the imbalance between recollection and familiarity that is the most likely cause of the mirror effect.     

Remember,know, confidence and the mirror effect: Changes as a function of discriminability conditions

Recognition memory for Spanish-Catalan cognate and noncognate words was tested at retention intervals of 20 minutes, 1 hour, and 24 hours (Experiment 1) using a remember/know response procedure, and requiring a confidence judgement on the yes/no response. Noncognate words were accompanied by more “remember” responses than cognates, and overall A' was significantly different from remember A', except in the cognate condition at the longest retention interval. A strong mirror effect for the cognate-noncognate stimulus class was found for overall responding, and for high but not low confidence, indicating a differential use of recollection and familiarity in recognition. In general, the pattern of results was inconsistent with Donaldson's (1996) signal detection model, indicating that, when available, subjects use two different sources of information for discrimination. The examination of individual hits and false alarms as a function of confidence indicated that “remember” is uniformly associated with high confidence, but “know” shows a bipolar pattern. In Experiment 2, new and old words were repeated at test 2 and 3. Repetition greatly affected the difference between the discrimination indices, indicating that an increase in the familiarity of new words prevented the use of a dual source of information in recognition. Results are discussed in terms of Rajaram's distinctiveness (1996, 1998) and Reder, Nhouyvanisvong, Schunn, Ayers, Angstadt, and Hiraki's (2000) SAC theories.