A perceptually based method for enhancing pulmonary nodule recognition

RATIONALE AND OBJECTIVES. Feedback of chest areas receiving prolonged gaze durations significantly increases nodule detection performance. Why feedback circling enhances performance when other cueing methods produce equivocal results was assessed. METHODS. Chest and noise images with nodule targets were used to determine: what type of cue is most effective; whether circling influences the way the eye samples the target; whether circling limits processing of distracting information outside its boundary. RESULTS. Circling improves performance more than cues with less complete boundaries and increases the accuracy and frequency with which nodules are fixated. Outside distractors were detected less often with than without the circle present. CONCLUSIONS. Circling isolates the abnormal region from the rest of the image, making disembedding and integration of nodule features more likely and insulates this region from distractors. The facilitative effects of circling are generalizable to other images in which low contrast targets are embedded in noisy backgrounds.