The Generic-Viewpoint Assumption and Illusory Contours

Perception ◽  
10.1068/p3016 ◽  
2000 ◽  
Vol 29 (3) ◽  
pp. 303-312
Author(s):  
Marc K Albert ◽  
Donald D Hoffman
Keyword(s):  
Machine Vision ◽  
Infinite Number ◽  
Illusory Contour ◽  
Human Vision ◽  
Visual Images ◽  
Illusory Contours ◽  
Contour Perception ◽  
The World

Visual images are ambiguous. Any image, or collection of images, is consistent with an infinite number of possible scenes in the world. Yet we are generally unaware of this ambiguity. During ordinary perception we are generally aware of only one, or perhaps a few of these possibilities. Human vision evidently exploits certain constraints—assumptions about the world and images formed of it—in order to generate its perceptions. One constraint that has been widely studied by researchers in human and machine vision is the generic-viewpoint assumption. We show that this assumption can help to explain the widely discussed fact that outlines of blobs are ineffective inducers of illusory contours. We also present a number of novel effects and report an experiment suggesting that the generic-viewpoint assumption strongly influences illusory-contour perception.

The Multiple Determination of Illusory Contours: 2. An Empirical Investigation

Perception ◽  
1983 ◽  
Vol 12 (3) ◽  
pp. 293-303 ◽  
Author(s):  
Diane F Halpern ◽  
Billie Salzman ◽  
Wayne Harrison ◽  
Keith Widaman
Keyword(s):  
Illusory Contour ◽  
Factor Model ◽  
Illusory Contours ◽  
Contour Perception ◽  
Confirmatory Factor ◽  
Linear Effects ◽  
Explained Variance ◽  
Taxonomic Approach ◽  
Contour Strength

Judgments of contour strength or saliency for twenty-four illusory-contour configurations were subjected to a confirmatory factor analysis. A four-factor model that posited the involvement of simultaneous contrast, linear effects (assimilation and dissimilation), depth/completion cues, and feature analyzers accounted for a substantial proportion of the variance in judgments of illusory-contour strength. The hierarchical addition of a fifth factor, diffuse illusory contours, significantly improved the overall fit of the model, but added little to the proportion of explained variance. The taxonomic approach adopted provides support for a multiprocess model of illusory-contour perception.

The Determinants of Illusory-Contour Perception

Perception ◽  
1981 ◽  
Vol 10 (2) ◽  
pp. 199-213 ◽  
Author(s):  
Diane F Halpern
Keyword(s):  
Illusory Contour ◽  
Experimental Results ◽  
Brightness Contrast ◽  
Apparent Depth ◽  
Primary Role ◽  
Illusory Contours ◽  
Contour Perception

The term ‘illusory contours' refers to contours perceived where none physically exist. Three hypotheses that have been successful in their ability to account for this phenomenon invoke: (i) apparent depth; (ii) brightness contrast; and (iii) use of figural cues. An experiment has been designed to determine the extent to which each hypothesis accounts for the overall variation in subjects' responses to illusory contours when all three hypotheses are considered simultaneously. Experimental results suggest that different processes may assume a primary role in the perception of illusory contours depending upon the type of inducing area and the configuration. The results highlight the multifaceted nature of the processes involved, and indicate that no single theory can explain the perception of illusory contours.

The Multiple Determination of Illusory Contours: 1. A Review

Perception ◽  
1983 ◽  
Vol 12 (3) ◽  
pp. 281-291 ◽  
Author(s):  
Diane F Halpern ◽  
Billie Salzman
Keyword(s):  
Illusory Contour ◽  
Brightness Contrast ◽  
Simultaneous Contrast ◽  
Illusory Contours ◽  
Contour Perception ◽  
Partial Activation ◽  
Multiple Determination

Four theories of illusory-contour perception are reviewed—brightness contrast (simultaneous contrast, assimilation, and dissimilation), depth/completion, partial activation of neural feature analyzers, and the diffuse—sharp dichotomy. It is concluded that the processes and mechanisms involved in illusory-contour perception most likely depend upon the stimulus elements used in the illusory-contour display.

scholarly journals Influence of Parallel and Orthogonal Real Lines on Illusory Contour Perception

2010 ◽  
Vol 103 (1) ◽  
pp. 55-64 ◽  
Author(s):  
Barbara Dillenburger ◽  
Anna W. Roe
Keyword(s):  
Real Line ◽  
Illusory Contour ◽  
Contextual Effects ◽  
Line Orientation ◽  
The Other ◽  
Imaging Data ◽  
Illusory Contours ◽  
Contour Perception ◽  
Parallel Lines

Real lines and illusory contours (ICs) have been reported to either interfere with or facilitate the perception of the other, depending on real line orientation and contrast. Here we investigate contextual effects of real lines on illusory contour perception. Curvature discrimination thresholds of Kanizsa-contours were measured for superimposed real lines of different sub- and suprathreshold contrasts. We find that parallel lines interfere with curvature discrimination at suprathreshold, whereas orthogonal lines interfere at subthreshold contrasts. We did not find stable facilitating effects of lines in any orientation or contrast. These results are discussed in relation to existing physiological and imaging data.

Affect from mere perception: Illusory contour perception feels good.

Emotion ◽  
2017 ◽  
Vol 17 (5) ◽  
pp. 856-866 ◽  
Author(s):  
Thorsten M. Erle ◽  
Rolf Reber ◽  
Sascha Topolinski
Keyword(s):  
Illusory Contour ◽  
Contour Perception

The Problem of Alternative Monotheisms: Another Serious Challenge to Theism

2018 ◽  
Vol 10 (1) ◽  
pp. 31-51
Author(s):  
Raphael Lataster
Keyword(s):  
Infinite Number ◽  
Current Evidence ◽  
God Concept ◽  
Classical Theism ◽  
The World ◽  
Divine Transcendence ◽  
Hiddenness Of God

Theistic and analytic philosophers of religion typically privilege classical theism by ignoring or underestimating the great threat of alternative monotheisms.[1] In this article we discuss numerous god-models, such as those involving weak, stupid, evil, morally indifferent, and non-revelatory gods. We find that theistic philosophers have not successfully eliminated these and other possibilities, or argued for their relative improbability. In fact, based on current evidence – especially concerning the hiddenness of God and the gratuitous evils in the world – many of these hypotheses appear to be more probable than theism. Also considering the – arguably infinite – number of alternative monotheisms, the inescapable conclusion is that theism is a very improbable god-concept, even when it is assumed that one and only one transcendent god exists.[1] I take ‘theism’ to mean ‘classical theism’, which is but one of many possible monotheisms. Avoiding much of the discussion around classical theism, I wish to focus on the challenges in arguing for theism over monotheistic alternatives. I consider theism and alternative monotheisms as entailing the notion of divine transcendence.

scholarly journals Ways of Seeing Christ the Judge: The Iconography of Christ III and its Visual Context

Neophilologus ◽  
2021 ◽  
Author(s):  
Natalie Jones
Keyword(s):  
Detailed Analysis ◽  
Visual Imagery ◽  
Careful Analysis ◽  
Visual Images ◽  
Detailed Knowledge ◽  
Visual Context ◽  
Notable Feature ◽  
The World ◽  
Dual Perspective ◽  
The Mind

AbstractThis article examines the iconographic programme of the Last Judgement scene depicted in Christ III. A notable feature of the poem’s detailed visual programme is the way in which it provides the audience with a single, panoramic vision that encompasses the divergent perspectives of the blessed and the damned. It is on account of this dual perspective that the poem, through its precise use of language and imagery, presents the audience with a bifocal vision of Christ as King of Kings and Judge of the World, in keeping with the words of Revelation 19:16. A detailed analysis of the poem’s imagery, however, suggests that its portrait of Christ as Judge is not only informed by scripture and exegetical sources, but is also indebted to contemporary visual imagery, particularly the depiction of Christ as Majestas Domini, or Christ in Majesty. As a result, and by approaching the poem’s imagery from an iconological perspective, it is argued that the poet of Christ III had a detailed knowledge of contemporary Christological motifs. Furthermore, a careful analysis of the language used to describe the Judgement scene, and particularly the depiction of Christ as Judge, suggests that the poet intentionally seeks to evoke a range of specific visual images in the mind of his audience in order to amplify the poem’s instructive and penitential aims.

scholarly journals Perception of the World through the Prism of Culture

2013 ◽  
Vol 9 (1-2 (11)) ◽  
pp. 130-133
Author(s):  
Narine Harutyunyan
Keyword(s):  
Religious Beliefs ◽  
Moral Values ◽  
Visual Images ◽  
Cultural Traditions ◽  
Cognitive Patterns ◽  
The World

The world is not perceived as static. It is in constant movement and is described by religious beliefs, cultural traditions, moral values and a system of stereotypes. While perceiving the world man creates cognitive patterns which, together with individual meanings, reflect common underlying features of the world perception among different people. Among the standards that might describe and characterize the world are: visual images, smells and scents, i.e. perceptions received through different senses.

Insect perception of illusory contours

1992 ◽  
Vol 337 (1279) ◽  
pp. 59-64 ◽  
Keyword(s):  
Human Visual System ◽  
Illusory Contour ◽  
Optic Lobe ◽  
Insect Vision ◽  
Local Contrast ◽  
Fault Line ◽  
Illusory Contours ◽  
Striped Pattern ◽  
Processing Power ◽  
As If

The human visual system sees an illusory contour where there is a fault line across a regular striped pattern. We demonstrate that bees respond as if they see the same illusory contour. There is also a type of neuron in the lobula of the dragonfly optic lobe which responds directionally to motion of the illusory contour as if to an edge or line. Apparently insects have a mechanism that sees illusory contours and therefore assists in the demarcation of edges and objects at places where local contrast falls to zero at an edge, or where one textured object partially obscures another. These results suggest that insect vision, although spatially crude and low in processing power, sees separate objects by similar mechanisms to our own.

Neuronal correlates of real and illusory contour perception: functional anatomy with PET

1999 ◽  
Vol 11 (11) ◽  
pp. 4024-4036 ◽  
Author(s):  
Jonas Larsson ◽  
Katrin Amunts ◽  
Balázs Gulyás ◽  
Aleksandar Malikovic ◽  
Karl Zilles ◽  
...  
Keyword(s):  
Illusory Contour ◽  
Functional Anatomy ◽  
Contour Perception
Sign in / Sign up

Export Citation Format

Share Document