title: Application of a computational decision model to examine acute drug effects on human risk taking.
abstract: In 3 previous experiments, high doses of alcohol, marijuana, and alprazolam acutely increased risky decision making by adult humans in a 2-choice (risky vs. nonrisky) laboratory task. In this study, a computational modeling analysis known as the expectancy valence model (J. R. Busemeyer & J. C. Stout, 2002) was applied to individual-participant data from these studies, for the highest administered dose of all 3 drugs and corresponding placebo doses, to determine changes in decision-making processes that may be uniquely engendered by each drug. The model includes 3 parameters: responsiveness to rewards and losses (valence or motivation); the rate of updating expectancies about the value of risky alternatives (learning/memory); and the consistency with which trial-by-trial choices match expected outcomes (sensitivity). Parameter estimates revealed 3 key outcomes: Alcohol increased responsiveness to risky rewards and decreased responsiveness to risky losses (motivation) but did not alter expectancy updating (learning/memory); both marijuana and alprazolam produced increases in risk taking that were related to learning/memory but not motivation; and alcohol and marijuana (but not alprazolam) produced more random response patterns that were less consistently related to expected outcomes on the 2 choices. No significant main effects of gender or dose by gender interactions were obtained, but 2 dose by gender interactions approached significance. These outcomes underscore the utility of using a computational modeling approach to deconstruct decision-making processes and thus better understand drug effects on risky decision making in humans.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, 77030, USA. scott.d.lane@uth.tmc.edu
authors.forename: Scott D
authors.initials: SD
authors.lastname: Lane
authors.forename: Eldad
authors.initials: E
authors.lastname: Yechiam
authors.forename: Jerome R
authors.initials: JR
authors.lastname: Busemeyer
mesh_terms: D000428:Alcohol Drinking / Q000523:psychology*; D000525:Alprazolam / Q000008:administration & dosage*; D002755:Choice Behavior / Q000187:drug effects; D003657:Decision Making / Q000187:drug effects*; D005260:Female; D006801:Humans; D007858:Learning / Q000187:drug effects; D008297:Male; D008385:Marijuana Smoking / Q000523:psychology*; D008568:Memory / Q000187:drug effects; D008960:Models, Psychological; D009042:Motivation; D012309:Risk-Taking; D012727:Sex Characteristics; D019966:Substance-Related Disorders / Q000523:psychology*
chemical_list: D000525:Alprazolam