Affect and memory: effects of pleasant and unpleasant odors on retrieval of happy and unhappy memories.

Interpretation of studies of induced mood and memory is complicated by the fact that mood induction procedures may elicit mood-related cognition in addition to mood per se. We used odors to produce positive and negative experiences with minimal cognitive involvement. College women recalled memories cued by neutral words while exposed to a pleasant odor, unpleasant odor, or no odor. Subjects then rated their memories as to how happy or unhappy the events recalled were at the time they occurred. Subjects in the pleasant odor condition produced a significantly greater percentage of happy memories than did subjects in the unpleasant odor condition. When subjects who did not find the odors at least moderately pleasant or unpleasant were removed from the analysis, more pronounced effects on memory were found. The results suggest that congruence between the general hedonic tone of current experience and that of material in long-term memory is sufficient to bias retrieval.