ABSTRACT
Mean depth settings and subjective reports appear to confirm previous subjective reports from users of the X-Chrom prescription lens that Pulfrich Effect depth distortions decrease with continued exposure to light intensity disparity. Depth setting variability across Days of exposure indicates a rapid increase in depth judgment errors which persists without decrement across Days. This increased variability, the apparent depth decrements, and color discrimination improvements shed light on the visual processing underlying the Pulfrich Effect and reveal a potentially dangerous illusion.
Subject(s)
Contact Lenses/adverse effects , Depth Perception , Perceptual Distortion , Adult , Color Perception/physiology , Color Vision Defects/rehabilitation , Depth Perception/physiology , Female , Humans , Light , Male , Optical Illusions/physiology , Perceptual Distortion/physiology , Visual Cortex/physiologyABSTRACT
This study investigated apparent depth and pattern using four conditions of hemiretinal filtering with 19 male and five female college-student SS. The results for both the depth and pattern of pendulum movement challenge the adequacy of the long-standing latency hypothesis. Apparent depth occurred without simultaneous stimulation disparity and smooth figure-8 patterns resulted only when the stimulation disparity was induced for both cortical hemispheres. The findings suggest independence of depth and pattern processing in the central nervous system and underscore the importance of viewing perception as an active constructive process.
Subject(s)
Illusions/physiology , Optical Illusions/physiology , Retina/physiology , Visual Perception/physiology , Adult , Depth Perception/physiology , Dominance, Cerebral/physiology , Female , Humans , Male , Motion Perception/physiologyABSTRACT
The present experiment tested the hypothesis that as the visual salience of stimuli decreases, the use of nominal representations as a basis for matching forms increases. The visual salience manipulation was based upon psychophysical studies showing that the dimension compactness possesses higher visual salience for the human observer than the dimension jaggedness. Subjects were asked to judge whether two successively presented forms were the same or different with respect to their position on the compactness or jaggedness dimension. Reaction times suggested an inverse relationship between the use of nominal representations and the visual salience of the dimension employed as a criterion for matching.
