Fear shapes information acquisition in decisions from experience.

Before making decisions, people often need to explore their environment to learn about initially uncertain outcomes. To date, it remains unknown to what extent a person's emotional state shapes exploration in such decisions from experience. It has been suggested that fear regulates people's informational interface with the external world through its physiological expression (e.g., a more effective sampling of the visual field from widened eyes). We investigated whether-as suggested by appraisal tendency theories of emotions-the "emotional feeling" of fear triggers analogous changes in exploration, in terms of increased information sampling in decisions from experience. In two studies, one with naturally occurring emotional states and one with induced emotional states, we found that fearful (relative to happy) people sampled substantially more information before making a final choice. These different degrees of exploration influenced the experience of rarity and, in turn, final choices. We discuss the extent to which increased information acquisition is adaptive.