The naso‐temporal division of the monkey's retina

Abstract By sectioning one optic tract in each of four monkeys, and studying the distribution within each pair of retinas of the ganglion cells which remained after the affected ganglion cells had undergone retrograde degeneration, a description was obtained of the areas of a retina from which ganglion cells project to the ipsilateral and contralateral sides of the brain. Confirming previous work, ganglion cells in temporal retina were observed to project to the ipsilateral side, and cells in nasal retina to the contralateral side. It was noted, however, that ipsi‐ and contralaterally projecting areas of retina overlap along a vertically‐oriented median strip, which is about 1° wide, and is centred on the fovea. Within this strip ipsi‐ and contralaterally projecting cells intermingle. Some functional implications of this result are discussed.