(1) The principal goal of the research program is to use anatomical and electrophysiological methods to determine how the visual cortex and thalamus are subdivided and interconnected in primates. The approach is comparative so that the basic plan of organization and major variations of that plan can be determined. Combined anatomical methods of determining connections and electrophysiological recording and stimulation procedures will be used to investigate visual cortex in the occipital, temporal, and parietal lobes, as well as visuomotor areas of the frontal lobe. The result will be a better understanding of how the human visual system processes information and mediates its functions. This information will also lead to a better understanding of how brain damage alters normal functions. (2) Other studies are designed to determine how visual cortex is changed by damage to inputs form the retina or early stages of processing in adult and developing animals. These investigations will help reveal normal processes of self-organization and development in the visual system and responses to injury that may have important implications for functional recovery. (3) A final goal will be to determine suitable animal models of ganglion cell death in the retina after cortical lesions. A better model could lead to critical studies of the factors that are important in cell loss and preservation, not only in the retina, but in the nervous system in general.