title: The stereoscopic sliver: a comparison of duration thresholds for fully stereoscopic and unmatched versions.
abstract: Just as positional disparities of image features seen with both eyes provide depth information, the presence of an area visible to one eye but not the other within a binocularly viewed scene can indicate an occlusion at a depth discontinuity. The close geometrical association between these two kinds of cues suggests they may both be exploited by stereopsis. To investigate this, we developed a novel binocular stimulus entirely lacking in classical disparity that contains an unmatched vertical sliver which elicits a warping of the surrounding surface to accommodate a depth discontinuity. We measured depth-discrimination performance at a range of stimulus durations, correcting for variations in stimulus visibility, to characterise the decline of the efficacy of the depth signal with limited integration time. Results show a close correspondence of performance for similar stimuli with unmatched features and classical binocular disparity across a sixtyfold range of viewing durations, supporting the notion of a close association between the two types of cues in human stereopsis. Control experiments excluded simple eye-of-origin cues and long-range false matches as explanatory factors.
authors.affiliation: School of Psychology, University of New South Wales, Sydney, NSW 2052, Australia. bensan@nasneb.com
authors.forename: W L Ben
authors.initials: WL
authors.lastname: Sachtler
authors.forename: Barbara
authors.initials: B
authors.lastname: Gillam
mesh_terms: D003463:Cues; D003867:Depth Perception / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology; D006801:Humans; D011601:Psychophysics; D012684:Sensory Thresholds / Q000502:physiology; D015357:Vision Disparity / Q000502:physiology*; D015348:Vision, Binocular / Q000502:physiology