The retinotopic organization of lateral suprasylvian visual areas in the cat.

This is the second in a series of papers in which we describe our continuing efforts to define functional units of visual cortex based upon electro-physiological mapping of single and multiple unit activity in both awake and the nitrous oxide anesthetized cats. In the first paper (Tusa, Palmer and Rosenquist, '78), the extent and retinotopic organization of area 17 were described. In this paper, we describe the somewhat more complex organization of the visual cortex lying on the banks of the middle and posterior suprasylvian sulci. This region of cortex consists of six retinotopically organized units. These areas are arranged as three roughly mirror symmetrical pairs separated in each case by the fundus of the middle or posterior suprasylvian sulci. Some thalamo-cortical autoradiographic material is presented which supports this parcellation of the cortex.