Studying some temporal aspects of stereoscopic processing in order to clarify phenomena of stereoscopic persistence and investigate how the brain deals with stereoscopic stimuli that involve various types of clues or difficulties (simple versus complex, with or without oriented elements, with or without curvature, with explicit or camouflaged shapes, with or without disparity discontinuities).A modest increase in the duration of binocular intervals B makes it possible much larger increase in the duration of the purely monocular presentation M. The M’s are related to the binocular intervals B’s by a power law, of exponent around 1.3 - 2.5 depending on stimulus complexity