Combined anatomical and electrophysiological studies on the boundary between the second and third visual areas of rhesus monkey cortex

Abstract Anatomical evidence (Cragg 1969; Zeki 1969) has shown that the horizontal meridian is represented at the boundary of the second and third visual areas of rhesus monkey cortex and that as one proceeds further anteriorly along V3 one reaches a region of V3 that is callosally connected and in which the vertical meridian is represented. We have confirmed these anatomical findings by recording from the cortex of monkeys in which the splenium of the corpus callosum had been sectioned before the recording experiments.