Self-relevance dynamically biases exploration and exploitation in value-based decisions

While adaptive decision-making requires balancing exploration and exploitation, dominant accounts often treat this trade-off as independent of social context. Drawing on theories of self-function and motivated cognition, we tested whether deciding for oneself versus others alters exploration-exploitation dynamics. Across two experiments, participants completed a restless multi-armed bandit task for themselves or a close friend under gain (Experiment 1) and loss (Experiment 2) conditions. Results indicated that self-other differences in choice behavior emerged dynamically over time rather than reflecting a static bias. An additional computational modeling analysis revealed that self-relevance was associated with increased sensitivity to value differences (i.e., inverse temperature), consistent with more deterministic choice (i.e., exploitation). Taken together, these findings demonstrate that self-relevance does not merely influence learning but dynamically shapes decision policies over time. More broadly, the results highlight the importance of motivational context in regulating how individuals balance information gain and reward during value-based decisions.