An electrophysiological study of the visual projection to the superior colliculus of the rat

Abstract

Abstract The topographical relations of the visual field with the superior colliculus of the rat was investigated using constant small visual stimuli and recording the electrical response of aggregate unit activity with fine tip metal microelectrodes. A precise essentially linear projection onto the contralateral colliculus was demonstrated after appropriate corrections for brain curvature were performed. The general pattern and arrangement of the retinotopic projection is similar to that found in infra‐mammalian vertebrates. An ipsilateral projection appears to be absent. The phasic properties and rhythmic discharge patterns of single units in the coliculus were studied with stationary and moving luminous stimuli.