Central vision of man and macaque: cone and rod sensitivity.

The distribution of photopic and scotopic sensitivity of the rhesus monkey has been described for central vision and compared to sensitivities of human observers. For small, brief, greeen and red test flashes the monkey's sensitivity was comparable to man, but was considerably more sensitive than man's to small, blue (450 nm) test flashes. This superior photopic sensitivity to blue was correlated with a low density of macular pigment. The scotopic sensitivities of man and monkey were comparable with the distribution of central sensitivity of the monkey being demonstrated to be related to the density of rods around the center fovea.