Effect of pre- and postnatal retinal deprivation on the striate-peristriate cortical connections in the rat.

The tangential distribution of the striate-peristriate cortical connections in normal, postnatally eye enucleated and congenitally anophthalmic rats, was studied after a single injection of wheat germ agglutinin conjugated with horseradish peroxidase into the striate cortex. The typical normal pattern of separate fields in the peristriate cortex is altered in eye enucleated animals, in such a way that their areal distribution in the cerebral cortex is increased and each field tends to fuse with the adjacent one. This process is more marked in anophthalmic animals, a finding that is in agreement with the notion that ganglion cells exert their influence before the visual pathway is functional.