Two experimental series are reported using both reaction time (RT) and a data-limited perceptual report to examine the effects of perceptual load on object-based attention. Perceptual load was manipulated across 3 levels by increasing the complexity of perceptual judgments. Data from the RT-based experiments showed object-based effects when the…

Object parts are signaled by concave discontinuities in shape contours. In seven experiments, we examined whether 5- and 6 1/2-month-olds are sensitive to concavities as special aspects of contours. Infants of both ages detected discrepant concave elements amid convex distractors but failed to discriminate convex elements among concave…

Summarizes the anatomical, physiological, and psychological evidence related to the primate visual system. States that comparison of perceptual abilities with the electrophysiological properties of neurons may help deduce functions of visual areas. (RT)