Culture-related differences in the neural processing of probability during mixed lottery value-based decision-making

This study evaluated how differences in economic risk-taking in Westerners and East Asians reflect cultural differences in the analytic or holistic processing of probabilistic outcomes during value-based decisions. Twenty-seven Americans (US) and 51 Taiwanese (TW) young adults completed a functional magnetic resonance imaging (fMRI) Lottery Choice Task (LCT) experiment. Participants accepted or rejected stakes with varying probabilities of winning or losing different magnitudes of points. TW participants accepted more stakes when win probabilities were > 0.50, whereas US participants reduced their acceptance rates of winning stakes more discriminately as win probabilities decreased. Both groups rejected losing stakes (win probabilities < 0.50) with similar frequency. Critically, ventromedial prefrontal cortex (VMPFC) responses correspondingly showed greater discrimination between win probability conditions in US than TW groups. Our findings highlight a neurocognitive mechanism in the VMPFC for how cultural differences in distinguishing between probabilistic reward outcomes shape neural computations of risk and prospects. •Taiwanese (TW) and Americans (US) performed a Lottery Choice Task.•TW were more risk-taking than US during winning stakes.•US showed more discrimination of different stake probabilities.•US showed more distinct ventromedial prefrontal responses to probabilities.•We show a neurocognitive mechanism for cultural differences in risk-taking.