Similar Processes Despite Divergent Behavior in Two Commonly Used Measures of Risky Decision Making.

Performance on complex decision-making tasks may depend on a multitude of processes. Two such tasks, the Iowa Gambling Task (IGT) and Balloon Analog Risk Task (BART), are of particular interest because they are associated with real world risky behavior, including illegal drug use. We used cognitive models to disentangle underlying processes in both tasks. Whereas behavioral measures from the IGT and BART were uncorrelated, cognitive models revealed two reliable cross-task associations. Results suggest that the tasks similarly measure loss aversion and decision-consistency processes, but not necessarily the same learning process. Additionally, substance-using individuals (and especially stimulant users) performed worse on the IGT than healthy controls did, and this pattern could be explained by reduced decision consistency.