Hemispheric asymmetries in different perceptual functions have been tested using the method of lateral presentation of stimuli i.e. in the left or right visual field. The first two experiments showed the right hemisphere advantage in the accuracy of detection of stereoscopic depth and in the strength of the tilt after-effect, i.e. in such phenomena which seem to be produced in the striate cortex. The third experiment, in which evoked potentials from point 01 and 02 during face perception were recorded, revealed the existence of right hemisphere superiority as early as 150 ms after stimulus presentation. These results indicate that the two hemispheres can already differ in their functions at the sensory level of processing.