Electrophysiological Correlate of Binocular Depth Perception in Man

IT is known that within the visual pathway of the brains of anaesthetized animals single units can be found which respond optimally when both eyes are simultaneously stimulated with light1–3. The characteristics of such binocular units are consistent with psychophysically observed features of binocular depth perception4–6. At present, human subjects have important advantages over animals in studies of stereopsis because with human subjects the critical binocular fusion and subjective reports of depth perception can easily be obtained. With human subjects, however, any electrophysiological information must be obtained by the analysis of scalp evoked potentials (EPs). This communication reports the finding of an EP correlate of binocular depth perception in man.