Abstract
BACKGROUND: Human decision-making is often affected by prior selections and their outcomes, even in situations where decisions are independent and outcomes are unpredictable. METHODS: In this study, we created a task that simulated real-life non-strategic gambling to examine the effect of prior outcomes on subsequent decisions in a group of male college students. RESULTS: Behavioral performance showed that participants needed more time to react after continuous losses (LOSS) than continuous wins (WIN) and discontinuous outcomes (CONTROL). In addition, participants were more likely to repeat their selections in both WIN and LOSS conditions. Functional MRI data revealed that decisions in WINs were associated with increased activation in the mesolimbic pathway, but decreased activation in the inferior frontal gyrus relative to LOSS. Increased prefrontal cortical activation was observed during LOSS relative to WIN and CONTROL conditions. CONCLUSION: Taken together, the behavioral and neuroimaging findings suggest that participants tended to repeat previous selections during LOSS trials, a pattern resembling the gambler's fallacy. However, during WIN trials, participants tended to follow their previous lucky decisions, like the 'hot hand' fallacy.