The Pollyanna effect versus loss attention: The role of event mixing in incidental memory of positive and negative events
Greater recall of positive than negative events has been observed in incidental memory studies. Conversely, findings indicate a negativity bias in people’s cognitive performance. Based on a two-process attention-strategy model, we suggest that a negativity bias in incidental memory performance emerges for non-mixed positive and negative events, while a positivity effect emerges given intermixed events. In Studies 1 and 2 participants performed a decision task with mixed positive and negative outcomes, and showed a robust positivity bias in their recollections. In Study 3 participants performed a task with non-mixed positive or negative outcomes, and exhibited a negativity bias in recollections as well as response time. In Study 4 we compared mixed and blocked schedules of positive and negative outcomes, and found that mixing trials eliminated the negativity bias. The findings indicate that humans show both positivity and negativity biases in their incidental recollections depending on the intermixture of events.