Experimental and Theoretical Studies of the Organization of Afferents to Single Orientation Columns in Visual Cortex

In the visual cortex, as in other neocortical areas in mammals, neuronal response properties are arranged in columns. Cortical columns were described in the earliest experiments of Hubel and Wiesel (1962), who demonstrated that all of the neurons within each radial column in the primary visual cortex respond selectively to elongated edges of a particular angle or orientation. Since then, a number of visual response properties, in addition to selectivity for stimulus orientation, have been found to be shared by the neurons within single cortical columns. Each column is specific for topog-raphy, in that all neurons have their receptive fields in a particular portion of the visual field; for ocular domi-nance, in that all neurons in a particular column will tend to respond more strongly to one eye than to the