Spatial organization by common-fate motion affects brightness computation on articulated surrounds(Summaries of Awarded Presentation at the 28th Annual Meeting)

Abstract

By adding small patches of different luminances to a uniform field surrounding a target, the effect of the surrounding luminance on target brightness can be enhanced (articulation effect). The present study investigated whether the articulation effect is governed only by retinal proximity or also affected by spatial organization by common-fate motion. The target in the present study was a moving patch located at the center of an articulated surround. It was moved with small patches and/or the uniform background within the surround with the same speed, direction, and timing. The target was easily grouped with the patches and/or the background depending upon what simultaneously moved, although retinal proximity was kept almost constant. The results indicated clear influences of spatial organization as well as retinal proximity on the articulation effect. These findings suggest that the brightness computation on the articulated field could depend upon both the spatial luminance distribution in the retinal image, and spatial structure where retinal elements were spatially organized by common-fate motion.