Binocular responses in the superior colliculus of the albino rat

The retinotopic map for the contralateral eye is similar to that found in the pigmented rats and in other rodents. Cells which had ipsilateral responses were recorded in a fairly large area in the rostral portion of the tectum. Their receptive fields lay from about 40 degrees in the contralateral hemifield to about 40 degrees in the ipsilateral hemifield. The ipsilateral response of a binocular cell is similar in almost every respect to its counterpart in the opposite eye except being very weak and that the receptive field is usually smaller. Most binocular cells are distributed in the Stratum griseum superficiale (SGS) and the Stratum opticum (SO). Less binocular cells recorded in the Stratum griseum intermediale (SGI) have more scattered distribution both in the size and in the position of the receptive field.