In two separate experiments, we show that stereo-deficient observers are no better than stereonormals at discriminating the eye-of-origin of a monocular stimulation. Stereo-deficient observers are considered to have a preponderance of monocular neurons throughout their visual system, including the visual cortex. The results indicate that, in spite of their clear anatomical and physiological structure, such monocular neurons do not convey eye-of-origin information to consciousness.