Curiosity and surprise differentially affect memory depending on age.

State and trait epistemic curiosity can promote various aspects of cognition and behavior. However, possible age-related changes, a link to surprise, and formal education remain understudied. In three behavioral experiments, with n = 54 in experiment 1, n = 81 in experiment 2, and n = 196 in experiment 3, we could show that state but not trait epistemic curiosity drives long-term memory for relevant information in young and healthy older adults (experiment 1 and 2). This effect was further modulated by surprise in young but less in older adults, which is compatible with predictive coding theories and the notion of a quadratic effect of arousal on cognition that vanishes with age (experiment 2). Finally, in a mediation model, state epistemic curiosity could be predicted directly from trait epistemic curiosity and indirectly via formal education (experiment 3). Our findings specify how state and trait curiosity, together with surprise, promote learning and facilitate knowledge acquisition across the adult lifespan.