The Guidance of Attention 1 The Guidance of Attention to Objects and Locations by Long Term Memory of Natural Scenes

Four flicker change detection experiments demonstrate that scene-specific long term memory guides attention to both behaviorally relevant locations and objects within a familiar scene. Subjects performed an initial block of change detection trials, detecting the addition of an object to a natural scene. After a 30-minute filled delay, subjects performed an unanticipated second block of trials. When the same scene occurred in the second blocks of trials, the change within the scene could be identical to the original change, a new object appearing in the original change location, the same object appearing in a new location, or a new object appearing in a new location. Results suggest that attention is rapidly allocated to previously relevant locations and then to previously relevant objects. This pattern of locations dominating objects remained when object identity information was made more salient. We also used eye tracking to verify that scene memory influences the allocation of attention resulting in more direct scan paths to previously relevant locations and objects. This contextual guidance suggests that a high capacity long term memory for scenes is used to insure that limited attentional capacity is allocated efficiently rather than being squandered.