Spectral Sensitivity Function Determined by the Visually Evoked Cortical Potential in Several Classes of Colour Deficiency (Cone Monochromatism, Rod Monochromatism, Protanopia, Deuteranopia)

Abstract

The spectral sensitivity function was studied by measuring the sensory threshold and by recording the visually evoked cortical potential in normal and colour-defective subjects (rod monochromatism, cone monochromatism, protanopia, deuteranopia).In the rod monochromat, the loss of sensitivity at increasing background illumination was higher as compared to the normal observer. The spectral sensitivity in the dark adapted state and during light adaptation was the same and Cone Monochromatism corresponded closely to the CIE scotopic luminosity curve In two protanopes and one cone monochromat, the photopic sensitivity curve was greatly reduced at longer wavelengths as compared to the normal observer. In a deuteranope, the sensitivity to the wavelengths tested was close to the CIEphotopic luminosity curve