Visual search is the task of finding a target in an image against a background of distractors. Unique features of targets enable them to pop out against the background, while targets defined by lacks of features or conjunctions of features are more difficult to spot. It is known that the ease of target detection can change when the roles of figure and ground are switched. The mechanisms underlying the ease of pop out and asymmetry in visual search have been elusive. This paper shows that a model of segmentation in V1 based on intracortical interactions can explain many of the qualitative aspects of visual search
