Abstract
20 Ss were presented stereograms alternately to one eye. In a range of alternation rates of 2.1 to 10.0 cps with a mean of 5.5 cps, 18 Ss reported perception of stereoscopy. Due to retinal interactions between the two views the scene was also seen as vibrating. This phenomenon is important both to the question of the relation between monocular movement parallax and binocular stereopsis and to the theory of a binocular cyclopean field (Hochberg, 1964).