Rod-isolation techniques show that light-adapted human rods detect flicker frequencies as high as 28 hertz, and that the function relating rod critical flicker frequency to stimulus intensity contains two distinct branches. (MLH)

Summarizes the anatomical, physiological, and psychological evidence related to the primate visual system. States that comparison of perceptual abilities with the electrophysiological properties of neurons may help deduce functions of visual areas. (RT)