Binocular integration of partially occluded surfaces

Normal binocular vision can provide a view of an object partially occluded so that no part of it is seen by both eyes but all of it is seen by one or other eye. We used two-dimensional filtered noise textures to explore the conditions under which the visual system can piece together the monocular fragments of such occluded surfaces. When the fragments seen by left and right eyes are drawn from a continuous texture with strong horizontal correlation, observers see coherent surfaces reliably located in depth. When textures are discontinuous or have weaker horizontal correlation, or the left and right eyes' views represent unnatural depth relationships, no coherent surface is perceived, and binocular rivalry ensues. The discovery of coherent surfaces under our conditions seems to reflect the operation of a high-level integration process, failures of which drive rivalry.