Change detection: Paying attention to detail

ABSTRACT: Changes made during a brief visual interruption sometimes go undetected, even when the object undergoing the change is at the center of the observer's interest and spatial attention (Simons & Levin, 1998). This study examined two potentially important attentional variables in change blindness: spatial distribution, manipulated via set size, and detail level, varied by having the change at either the global or local level of a compound letter. Experiment 1 revealed that both types of change were equally detectable in a single item, but that global change was detected more readily when attention was distributed among several items. Variation of target level probability in Experiment 2 showed further that observers could flexibly set the detail level in monitoring both single and multiple items. Sensitivity to change therefore depends not only on the spatial focus of attention; it depends critically on the match between the detail level of the change and the level-readiness of the observer. 1