Decision-making in long-term cocaine users: Effects of a cash monetary contingency on Gambling task performance.
BACKGROUND
The Iowa Gambling task, which typically incorporates hypothetical monetary earnings and losses for performance, has been widely used to measure decision-making in substance abusers. We examined the effects of a cash monetary contingency on Gambling task performance in cocaine abusers and control participants.


METHODS
Twenty-two long-term cocaine smokers who met DSM-IV criteria for cocaine dependence and 24 non-cocaine-using control participants completed this study. Both groups were similar in terms of age, executive function, and self-reported alcohol and marijuana use. All participants performed the Gambling task under two counterbalanced conditions: under one condition, earnings and losses were hypothetical, and under the other condition, earnings and losses were in cash.


RESULTS
Condition x group interactions on card selection and task completion time were noted (p<0.05). Under the hypothetical payment condition, cocaine abusers selected a greater proportion of cards from disadvantageous decks than advantageous decks (p<0.05), but took a similar amount of time to complete the task, relative to control participants. However, under the cash payment condition, no group differences were seen for card selection and cocaine abusers took more time than controls to complete the task (p<0.05).


CONCLUSIONS
The application of tangible consequences improved the decision-making and effort of cocaine abusers on the Gambling task, relative to control participants. These findings underscore the importance of considering population-specific factors (e.g., sensitivity to instructional vs. consequential control) when conducting neuropsychological research in substance abusers.
Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, 1051 Riverside Drive #120, New York, NY 10032, USA. npv2101@columbia.edu
Nehal P
NP
Vadhan
Carl L
CL
Hart
Margaret
M
Haney
Wilfred G
WG
van Gorp
Richard W
RW
Foltin
D000328:Adult; D000428:Alcohol Drinking / Q000523:psychology; D019970:Cocaine-Related Disorders / Q000523:psychology*; D003657:Decision Making / Q000187:drug effects*; D004493:Education; D005006:Ethnicity; D005260:Female; D005715:Gambling / Q000523:psychology*; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000523:psychology; D009042:Motivation; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance / Q000187:drug effects*; D012959:Socioeconomic Factors; D014825:Vocabulary; D014888:Wechsler Scales