The Sizes of Cells Providing Interhemisphere and Intrahemisphere Connections in the Cat Visual Cortex after Lesioning of Binocular Vision

Abstract

The sizes (body areas) of 658 retrograde labeled cells in layers 2/3 of cortical fields 17 and 18 in both hemispheres were measured in intact cats, monocularly deprived cats, and cats with bilateral convergent strabismus after injection of horseradish peroxidase into the eye dominance columns of these fields. The mean size of callosal cells in all groups of cats was significantly greater than the mean size of cells providing intrahemisphere connections. The mean sizes of callosal cells in monocularly deprived cats and cats with strabismus were significantly greater than the mean size of callosal cells in intact cats, by 26.6% and 20.2%, respectively. The mean size of intrahemisphere cells in monocularly deprived cats was not different from the mean sizes of interhemisphere cells in cats with strabismus and intact cats. These data lead to the conclusion that impairments to binocular vision lead to increases in the sizes of callosal cells in the visual cortex.