Within visual cortex individual areas integrate local information through lateral and columnar intra-areal connections. Primary visual cortex and visual association areas are connected through inter-areal feedforward and feedback connections. In order to gain a better understanding of the relative roles of interareal connections in visual information processing, one of the goals of this proposal is to determine the precise anatomical and functional organization of feeforward and feedback connections between primate visual cortical areas V1 and V2, and to investigate the possible existence of multiple systems of feedforward and feedback connections that relate to different V1 and V2 layers and functional compartments. Furthermore, in order to understand the specific contribution of inter- and intra-areal circuits to the classical and non-classical receptive field properties of visual cortex neurons, a second goal of this proposal is to investigate how the spatial dimensions and organization of individual V2 cells' receptive fields are reflected by the spatial organization of inter-areal V1-to V2 feedforward connections and by intra-areal V2 connections. ? ?