Illusions of filled lateral and angular extent. The role of cortical feature detectors.
The common principle of the illusions found by Helmholtz and Botti is the overestimation of a filled extent. They differ in that Helmholtz's illusions of filled angular extent can be accounted for in terms of spatial two-line interactions, whereas Botti's illusions of filled lateral extent cannot. The former observation is consistent with the assumption of interacting orientation-detectors in the visual cortex. The Botti illusion probably depends on global computation in the visual system.
D006801:Humans; D008433:Mathematics; D008960:Models, Psychological; D013028:Space Perception; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception