[The tangential segregation of simple and complex cells in the visual cortex and their connections. The universal...

Guinea-pig studies testify that in rodents (like in higher mammals) the primary afferents from the thalamus and inferior cortical afferents converge on discrete columns about 200 mcm in size with zones of secondary convergence between them. The cortical columns seem to be primary basic and universal cortical modules, since they have similar dimensions and uniform organization in different mammals. The columns concentrate simple cells (with complex ones among them) and afferent inhibitory neurons; these models are involved in the first stage of cortical integration. Local connections of the primary modules differ from those of the secondary intermediary zones, which are poor narrow in rodents. The intermediary zones progressively develop in phylogeny, and in higher mammals they excel the primary modules in dimensions.