Abstract
Recent research indicates that people greatly overestimate change detection ability. This metacognitive error is referred to as change blindness blindness (CBB). CBB persists even when subjects are reminded of the role memory plays in detecting changes and when long delays are inserted between the pre- and postchange views. Here, we examine subjects' beliefs about the role of intention in detecting changes. If subjects do not understand that actively searching for changes increases change detection, predicted change detection performance for intentional and incidental change detection tasks should be similar. In Experiment 1, we asked subjects to predict their ability to detect changes when changes were unexpected (an incidental change detection task) or to detect changes when changes were expected (intentional change detection task). Predictions were not significantly different for the two tasks. In Experiment 2, subjects predicted change detection performance for a task in which they would be performing another task (a cover task) and not looking for changes. Subjects' predictions for the incidental change detection task were significantly less optimistic than predictions for the intentional change detection task. These findings suggest that subjects do not readily appreciate the role of intention in detecting changes. However, if explicit instructions inform subjects that their attention will be directed to a task other than detecting changes, subjects are able to make more accurate predictions.