The stationarity hypothesis: An allocentric criterion in visual perception

Mark Wexler (1) , Ivan Lamouret (1) , Jacques Droulez (1)

1 LPPA - Laboratoire de Physiologie de la Perception et de l'Action

Having long considered that extraretinal information plays little or no role in spatial vision, the study of structure from motion (SfM) has confounded a moving observer perceiving a stationary object with a non-moving observer perceiving a rigid object undergoing equal and opposite motion. However, recently it has been shown that extraretinal information does play an important role in the extraction of structure from motion by enhancing motion cues for objects that are stationary in an allocentric, world-fixed reference frame (Wexler et al., 2001). Here we test whether stationarity per se is a criterion in SfM by pitting it against rigidity. We have created stimuli that, for a moving observer, other two interpretations: one that is rigid but non-stationary, another that is more stationary and less rigid. In two experiments, with subjects reporting either structure or motion, we show that stationary, non-rigid solutions are preferred over rigid, non-stationary solutions; and that when no perfectly stationary solution is available, the visual system prefers the solution that is most stationary. These results demonstrate that allocentric criteria, derived from extra-retinal information, participate in reconstructing the visual scene.

Mots clés: Depth Perception; Head Movements; Motion Perception; Kinesthesis; Psychophysics

Domaines: Psychologie

Mark Wexler, Ivan Lamouret, Jacques Droulez. The stationarity hypothesis: An allocentric criterion in visual perception. Vision Research, 2001, 41, pp.3023-3037. ⟨hal-00000020⟩