Perception of local three-dimensional shape.

F Phillips; J T Todd

doi:10.1037//0096-1523.22.4.930

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PubMed · 8756960

Perception of local three-dimensional shape.

F Phillips·J T Todd

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Abstract

The authors present a series of 4 experiments designed to test the ability to perceive local shape information. Observers were presented with various smoothly varying 3-dimensional surfaces where they reported shape index and sign of Gaussian curvature at several probe locations. Results show that observers are poor at making judgments based on these local measures, especially when the region surrounding the local point is restricted or manipulated to make it noncoherent. Shape index judgments required at least 2 degrees of context surrounding the probe location, and performance on sign of Gaussian curvature judgments deteriorated as the contextual information was restricted as well.

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Attention Depth Perception Discrimination Learning Humans Normal Distribution Optical Illusions Orientation Pattern Recognition, Visual Psychophysics Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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F Phillips, J T Todd. 1996. Perception of local three-dimensional shape.. https://doi.org/10.1037/%2F0096-1523.22.4.930

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