Change Blindness Blindness: The Metacognitive Error of Overestimating Change-detection Ability

Recent research has demonstrated that subjects fail to detect large between-view changes to natural and artificial scenes. Yet, most people (including psychologists) believe that they would detect the changes. We report two experiments documenting this metacognitive error. In Experiment 1, students in a large General Psychology class were asked if they thought they would notice the change in four different situations previously tested by Levin and Simons (1997) and Simons and Levin (1998). Most claimed that they would have noticed even relatively small changes that real observers rarely detected. In Experiment 2, subjects were tested individually and half were asked to predict whether someone else would detect the changes. Subjects again overestimated the degree to which changes would be detected, both by themselves and by others. We discuss possible reasons for these metacognitive errors including distorted beliefs about visual experience, change, and stability.