Conference on Cognitive Computational Neuroscience

Adaptive decision-making in noisy and changing environments must be jointly constrained by reward and uncertainty. Whereas rewards have robust behavioral effects in sequential decision-making, effects of uncertainty tend to be smaller and heterogeneous across subjects. Here we use a novel two-armed bandit task, which dissociates unexpected uncertainty from reward and expected uncertainty, and fMRI, to study the neural bases of individual differences in the neural representations of unexpected uncertainty. We find that (i) contributions of unexpected uncertainty to choice are heterogeneous across individuals but stable within individuals and (ii) variability in the neural representation of unexpected uncertainty corresponds to variability in its use during choices, in frontoparietal cortical regions previously implicated in uncertainty-related computations, but not in reward regions.