Adaptive Intuitions Shape Susceptibility to Misinformation

Belief in misinformation has been attributed to digital media environments that promote intuitive thinking, which is thought to foster uncritical acceptance of content. We propose that this intuitive ``truth bias’’ may be an ecologically rational adaptation to environments where information is typically accurate. Across a large-scale pre-registered survey experiment and an incentivized replication, we test whether intuitions indeed adapt to the base rate of true versus false content. Participants viewed news feeds composed primarily of either true or false headlines. We find that individuals make more—and faster—errors when encountering the less frequent headline type, and fewer errors with the more common type. Computational modeling of the deliberative process reveals these effects are driven by intuitive responses that function like Bayesian priors about content accuracy, which exhibit some persistence. Our findings suggest that susceptibility to misinformation may not merely reflect a cognitive failure, but rather a rational byproduct of learning from statistical regularities in digital environments.