[Organization of the afferent input to the superior colliculus of the rabbit brain]

The organization of afferent input to superior colliculus was studied in unanesthetized paralyzed rabbits. Two groups of afferent fibres with the average conduction velocities 3 and 6 m per s were determined. It was found that C1 and C2 components of the evoked potential reflect postsynaptic activity of collicular neurons activated by these groups of optic nerve fibres. The existence in rabbit of direct retino-tectal input to the superior colliculus is supposed.