scholarly journals Partial modal completion under occlusion: What do modal and amodal percepts represent?

2015 ◽  
Vol 15 (1) ◽  
pp. 22-22 ◽  
Author(s):  
T. R. Scherzer ◽  
V. Ekroll
Keyword(s):  
Modal Completion

A Modal Semantics of Negation in Logic Programming

1992 ◽  
Vol 16 (3-4) ◽  
pp. 231-262
Author(s):  
Philippe Balbiani
Keyword(s):  
Modal Logic ◽  
Logic Programming ◽  
Modal Logics ◽  
Kripke Models ◽  
Logic Programs ◽  
Modal Semantics ◽  
Soundness And Completeness ◽  
Modal Completion ◽  
Well Foundedness

The beauty of modal logics and their interest lie in their ability to represent such different intensional concepts as knowledge, time, obligation, provability in arithmetic, … according to the properties satisfied by the accessibility relations of their Kripke models (transitivity, reflexivity, symmetry, well-foundedness, …). The purpose of this paper is to study the ability of modal logics to represent the concepts of provability and unprovability in logic programming. The use of modal logic to study the semantics of logic programming with negation is defended with the help of a modal completion formula. This formula is a modal translation of Clack’s formula. It gives soundness and completeness proofs for the negation as failure rule. It offers a formal characterization of unprovability in logic programs. It characterizes as well its stratified semantics.

scholarly journals Abutting Objects Warp the Three-Dimensional Curvature of Modally Completing Surfaces

i-Perception ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 204166952090355 ◽  
Author(s):  
Peter U. Tse
Keyword(s):  
Visual Processing ◽  
Binocular Disparity ◽  
Three Dimensional ◽  
Surface Curvature ◽  
Amodal Completion ◽  
Three Dimensions ◽  
Curved Surfaces ◽  
Open Surface ◽  
Modal Completion

Binocular disparity can give rise to the perception of open surfaces or closed curved surfaces (volumes) that appear to vary smoothly across discrete depths. Here I build on my recent papers by providing examples where modally completing surfaces not only fill in from one depth layer’s visible contours to another layer’s visible contours within virtual contours in an analog manner, but where modally completing surface curvature is altered by the interpolation of an abutting object perceived to be connected to or embedded within that modally completing surface. Seemingly minor changes in such an abutting object can flip the interpretation of distal regions, for example, turning a distant edge (where a surface ends) into rim (where a surface bends to occlude itself) or turning an open surface into a closed one. In general, the interpolated modal surface appears to deform, warp, or bend in three-dimensions to accommodate the abutting object. These demonstrations cannot be easily explained by existing models of visual processing or modal completion and drive home the implausibility of localistic accounts of modal or amodal completion that are based, for example, solely on extending contours in space until they meet behind an occluder or in front of “pacmen.” These demonstrations place new constraints on the holistic surface and volume generation processes that construct our experience of a three-dimensional world of surfaces and objects under normal viewing conditions.

scholarly journals The Occlusion Illusion: Partial Modal Completion or Apparent Distance?

Perception ◽  
10.1068/p5694 ◽  
2007 ◽  
Vol 36 (5) ◽  
pp. 650-669 ◽  
Author(s):  
Stephen E Palmer ◽  
Joseph L Brooks ◽  
Kevin S Lai
Keyword(s):  
Apparent Distance ◽  
Modal Completion

A task-oriented taxonomy of visual completion

1998 ◽  
Vol 21 (6) ◽  
pp. 780-781 ◽  
Author(s):  
Carol Yin
Keyword(s):  
Perceptual Quality ◽  
Visual Completion ◽  
Modal Completion ◽  
Task Oriented

Differences and similarities between modal and amodal completions can only be understood by considering the goals of visual completion: unity, shape, and perceptual quality. Pessoa et al. cannot reject representational accounts of vision because of flaws with isomorphic representations of perceptual quality: representations and processes for perceptual quality (modal completion) and most likely dissociable from those for unity and shape (nonmodal completions).

A Functional Rôle for Illusory Colour Spreading in the Control of Focused Visual Attention

Perception ◽  
1997 ◽  
Vol 26 (11) ◽  
pp. 1397-1411 ◽  
Author(s):  
Greg Davis ◽  
Jon Driver
Keyword(s):  
Visual Attention ◽  
Functional Role ◽  
Amodal Completion ◽  
Focused Attention ◽  
Stereo Disparity ◽  
Stereoscopic Displays ◽  
Early Stages ◽  
Entire Object ◽  
Modal Completion

In cases of modal completion, illusory colour spreading fills in the surface of a subjectively completed shape. In amodal completion, shapes are likewise completed, but now behind a partial occluder, so that filling in of illusory colour to the completed region no longer arises. We consider the possible functional effects that illusory colour spreading may exert on later stages of vision, and argue that comparisons of modal with amodal completion may be particularly revealing in this regard. It is hypothesised that cueing the inducers of a modally completed object should attract attention to the entire object, including the completed region, owing to the colour spreading there. By contrast, changes to the inducers of a comparable amodally completed object should only attract attention to the inducing regions themselves. This prediction is supported by findings in two experiments with stereoscopic displays, with control conditions ruling out nonattentional accounts, or explanations in terms of stereo disparity alone rather than the presence versus absence of illusory colour. We argue that illusory colours get filled in at quite early stages during modal completion, precisely so that later stages of vision, such as focused attention, can then be driven by the completed regions in the same way as for uniform regions that are physically present in the image.

Modal Completion in the Poggendorff Illusion: Support for the Depth-Processing Theory

2002 ◽  
Vol 13 (4) ◽  
pp. 306-312 ◽  
Author(s):  
Branka Spehar ◽  
Barbara Gillam
Keyword(s):  
Poggendorff Illusion ◽  
Marked Decrease ◽  
Scene Perception ◽  
Oblique Line ◽  
Three Dimensional ◽  
Optical Illusions ◽  
Processing Theory ◽  
Depth Processing ◽  
Test Component ◽  
Modal Completion

The Poggendorff illusion is one of the most prominent geometrical-optical illusions and has attracted enduring interest for more than a hundred years. Most modern theories explain the illusion by postulating various kinds of distortion of the “test” component of the figure by the context or the inducing component. They make no reference to the importance of processes involved in three-dimensional scene perception for understanding the illusion. We measured the strength of the Poggendorff illusion in configurations containing solid inducing surfaces as opposed to the usual parallel lines. The surface, oblique-line, and background luminances were manipulated separately to create configurations consistent with modal completion of the obliques in front of the surface. The marked decrease in the size of the illusion in conditions favoring modal completion is consistent with claims that perceived spatial layout is a major determinant of the Poggendorff illusion.

Modal Completion: Critical Variables in Apparent Transparency

Perception ◽  
1987 ◽  
Vol 16 (6) ◽  
pp. 719-730
Author(s):  
Micheline Hambrouck ◽  
Georges Thinès ◽  
Michel Michiels
Keyword(s):  
Tunnel Effect ◽  
Structural Factors ◽  
Modal Completion ◽  
Stimulation Pattern ◽  
Spatiotemporal Integration

Conditions for perceptual modal completion are investigated using a stimulation pattern consisting of a figure moving behind a black opaque strip. This configuration leads, depending on conditions, either to the amodal Michotte tunnel effect, or to modal completion, ie the apparent transparency phenomenon. Four experiments are reported in which an attempt was made to define the critical variables of this latter effect. The results show that modal completion is not typically related to luminance interactions, ie to assimilation, but depends on the figural dominance of the filled-in object, this being determined by structural factors such as figure–ground relationship and stimulation change. The effect also depends strongly on the complexity of the spatiotemporal integration needed to maintain phenomenal identity of the object. No significant effect was found for the two other variables investigated, ie formal complexity of the figure and depth between the figure and the strip. The data are discussed in relation to those on moving visual phantoms.

scholarly journals The functional effects of modal versus amodal filling-in

1998 ◽  
Vol 21 (6) ◽  
pp. 752-753 ◽  
Author(s):  
Greg Davis ◽  
Jon Driver
Keyword(s):  
Amodal Completion ◽  
Functional Effect ◽  
Modal Completion

Comparisons between modally and amodally completed regions show that perceptual filling-in is not merely the ignoring of absences. Illusory filled-in colour arises for modal completion, but not for amodal completion in comparable displays. We find that attention spreads automatically to modally but not amodally completed regions from their inducers, revealing a functional effect of filled-in colour.

scholarly journals A Gauge Field Model of Modal Completion

2015 ◽  
Vol 52 (2) ◽  
pp. 267-284 ◽  
Author(s):  
Giovanna Citti ◽  
Alessandro Sarti
Keyword(s):  
Gauge Field ◽  
Field Model ◽  
Modal Completion
Sign in / Sign up

Export Citation Format

Share Document