Colour Confusion Produced by Voluntary Fixation

Abstract

When an observer stares at a colour-matching field, he may lose a great deal of his colour discrimination. Some find it possible to match any pair of spectral colours. Prolonged staring is not necessary, but the colours must be exactly matched in brightness. A systematic study of the fixation effects indicates that they are not due to a photochemical bleaching of pigments, but rather to the reduction of eye movements. Blue-green discrimination is affected more than yellow-red.