Form Perception

181.

Perceptual completion across the vertical meridian and the role of early visual cortex.

Perceptual completion can link widely separated contour fragments and interpolate illusory contours (ICs) between them. The mechanisms underlying such long-range linking are not well understood. Here we report that completion is much poorer when ICs ...
Jonathan Pillow, Nava Rubin (Neuron, 200202)
perceptual-completion-across-vertical-meridian-role-early-visual.asp

182.

The nature of illusory contour computation.

Neural correlates of illusory contour perception have been found in both the early and the higher visual areas. But the locus and the mechanism for its computation remain elusive. Psychophysical evidence provided in this issue of Neuron shows that ...
Tai Sing Lee (Neuron, 200202)
nature-illusory-contour-computation.asp

183.

The duration of 3-d form analysis in transformational apparent motion.

Transformational apparent motion (TAM) occurs when a figure changes discretely from one configuration to another overlapping configuration. Rather than an abrupt shape change, the initial shape is perceived to transform smoothly into the final shape as ...
Peter Ulric Tse, Nikos K Logothetis (Percept Psychophys, 200202)
duration-d-form-analysis-transformational-apparent-motion.asp

184.

A jigsaw-puzzle imagery task for assessing active visuospatial processes in old and young people.

Recent studies have suggested a theoretical distinction between active elaboration and passive storage in visuospatial working memory, but research with older adults has failed to demonstrate a differential preservation of these two abilities. The ...
John T E Richardson, Tomaso Vecchi (Behav Res Methods Instrum Comput, 200202)
jigsaw-puzzle-imagery-task-assessing-active-visuospatial-processes.asp

185.

Perceptual organization overcomes the effects of local surround in determining simultaneous lightness contrast.

Lightness induction can occur on the basis of the immediate surround of a region (local interactions) and also on the basis of global factors of perceptual organization. The experiments reported in this article used novel displays that made it possible ...
Tiziano Agostini, Alessandra Galmonte (Psychol Sci, 200201)
perceptual-organization-overcomes-effects-local-surround-determining.asp

186.

Role of onset asynchrony in contour integration.

Evidence that visual grouping is facilitated when elements comprising a foreground figure are presented simultaneously, and are temporally separated from elements comprising the background, has suggested cortical synchronous oscillations as a possible ...
William H A Beaudot (Vision Res, 200201)
role-onset-asynchrony-contour-integration.asp

187.

Fast long-range interactions in the early processing of luminance-defined form.

Within a duration of 20 ms humans can compare the orientations of two test lines so as to encode and place in memory their mean orientation and orientation difference while ignoring noise lines in the space between the test lines. Furthermore, ...
Radha P Kohly, D Regan (Vision Res, 200201)
fast-long-range-interactions-early-processing-luminance-defined-form.asp

188.

Early unilateral enucleation disrupts motion processing.

Previous research has shown that unilaterally enucleated observers demonstrate better luminance-defined form perception compared to monocularly viewing controls, and similar performance to control observers viewing binocularly (Vision Res. 37(17) (1997) ...
Jennifer K E Steeves, Esther G González, Brenda L Gallie, Martin J Steinbach (Vision Res, 200201)
early-unilateral-enucleation-disrupts-motion-processing.asp

189.

Two eccentricity-dependent limitations on subjective contour discrimination.

Eccentricity-dependent sensitivity losses in spatial discrimination tasks can often be overcome by scaling stimuli at each eccentricity by a factor F=1+E/E(2). However, because there may be more than one eccentricity-dependent limitation at play in a ...
Frédéric J A M Poirier, Rick Gurnsey (Vision Res, 200201)
two-eccentricity-dependent-limitations-subjective-contour.asp

190.

Absolute and relative effects of similarity and distance on grouping.

Four experiments are reported, the aim of which was to explore the achromatic-colour and distance relations that determine the probability of achromatic surfaces grouping perceptually. The first two experiments were performed to test Wertheimers ...
Sergio Cesare Masin (Perception, 2002)
absolute-relative-effects-similarity-distance-grouping.asp