Proceedings of the Annual Meeting of the Cognitive Science Society

Individuals often continue to rely on information even after credible sources have deemed it untrue, a phenomenon called the continued influence effect. This effect is especially consequential in politicised contexts where misinformation and polarisation threaten informed decision making. Existing accounts disagree on whether such belief persistence reflects cognitive failure or motivated reasoning, or whether it can instead arise from rational belief updating under constraints. We investigate this question by introducing delays during which no new information is provided, allowing memory for prior evidence to be less readily available. Across conditions, belief updating tracked the availability of evidence in memory, with beliefs regressing as supporting information decreased in availability and showing no systematic effects of political alignment. Moreover, belief trajectories aligned with predictions from Bayesian Network models parameterised using participants' own judgements. These findings suggest belief updating tracks memory availability and remains consistent with rational, evidence-based principles.