IMPULSIVITY AND HISTORY OF DRUG-DEPENDENCE

Impulsivity was contrasted between 32 subjects with a history of drug- dependence (DRUG +) and 26 subjects with no drug use history (DRUG -) using both behavioral and self-report measures. The hypothesis was tha t the DRUG + group would be more impulsive than the DRUG-group. Subjec ts in the DRUG + group self-reported more of a tendency toward impulsi vity than the DRUG-group in the situations posed in questionnaires. In the behavioural paradigm involving a choice between a smaller interme diate reward and a larger but delayed reward, DRUG + subjects selected the impulsive option more often, but these differences were not signi ficant. The DRUG + and DRUG-groups did differ on the mean delay interv al for the larger reward, indicating less ability to tolerate longer d elays for the larger reward. A frequency distribution of delay interva ls for the larger reward indicated that DRUG + subjects were more like ly to maintain very short intervals and less likely to maintain longer intervals. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved .