Neural unit in the perception of luminance gradients.

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Dept. of Psychology, University of Uppsala , Uppsala
Visual discrimination., Light -- Physiological ef
SeriesDept. of psychology, University of Uppsala, Sweden. Report 36
Classifications
LC ClassificationsBF21.A1 U6 no. 36
The Physical Object
Pagination(3), 9 l.
ID Numbers
Open LibraryOL5665575M
LC Control Number68117078

Neural mechanisms underlying depth perception are reviewed with respect to three computational goals: determining surface depth order, gauging depth intervals, and representing 3D surface geometry and object shape.

Accumulating evidence suggests that these three computational steps correspond to different stages of cortical by:   The neural substrate encoding luminance in the damaged hemisphere has a number of potential sites. As reviewed in the introduction, both subcortical (Goldberg and Wurtz, ) and extrastriate cortical visual areas (Benevento and Yoshida, ; Yukie and Iwai, ; Cowey and Stoerig, ; Girard et al.,) receive input in Cited by:   A real-time visual processing theory is used to unify the explanation of monocular and binocular brightness data.

This theory describes adaptive processes which overcome limitations of the visual uptake process to synthesize informative visual representations of the external world. The brightness data include versions of the Craik-O’Brien-Cornsweet effect Cited by: Grossberg, S., Studies of mind and brain: Neural principles of learning, perception, development, cognition, and motor control.

Boston: Reidel Press, a. zbMATH Google Scholar Grossberg, S., Associative and competitive principles of learning and development: The temporal unfolding and stability of STM and LTM by: To investigate the correlation between image resolution and depth perception of luminance-contrast difference/change more accurately, we should use more appropriate visual images having smoother and more edgeless luminance-contrast gradients, such as Gabor patch (Judson and Palmer, ).Cited by: 6.

The gradient system suggests how luminance gradients are processed by the visual system at an early level, and how they can give rise to perception of luminosity. As gradient representations are thought to be complementary to surface representations (i.e., lightness computations), possible interactions between both representations were by: The psychophysical anisotropy with respect to shading gradients implies an underlying neural bias.

Hanazawa and Komatsu [1] appear to have demonstrated such. On the Neural Correlates of Visual Perception Spatial gradients in size are a powerful stimulus for the experience of three-dimensional structure but the spatial extent of the field expressing the gradient may be Such updating may be essential for the perception and discrimination of luminance-based spatial form, especially that based Cited by: transformations of color signals in the primary visual cortex (V1) in macaque monkey.

These different color mechanisms may contribute separately to the perception of color boundaries and colored regions. Many cells in V1 respond to color and to black–white (luminance) patterns. These neurons are spatially selective and could provide signals about.

Neural Networks for Perception, Volume 1: Human and Machine Perception focuses on models for understanding human perception in terms of distributed computation and examples of PDP models for machine perception.

This book addresses both theoretical and practical issues related to the feasibility of both explaining human perception and Book Edition: 1. The present work proposes a new architecture for brightness perception, which aims to unify image processing with brightness perception.

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A successful unification has not been achieved so far, since models which predict brightness phenomena only rarely produce meaningful results when processing real-world images. A Neural Model of Surface Perception: Lightness, Anchoring, and Filling-In Stephen Grossberg and Simon Hong* Department of Cognitive and Neural Systems From Luminance to Anchored Lightness.

The retina receives luminance signals, which are a Early neural models of surface lightness perception simulated many classical psychophysical data. However, the results of this study lend support to the hypothesis that luminance gradients are instead a perceptual feature.

Here, I show how the perception of luminosity can emerge from a previously proposed neuronal architecture for generating representations of luminance gradients. Grossberg's “cells” considered as cell assemblies - Volume 6 Issue 4 - G.J. Dalenoort ( b) A paradox in the perception of luminance gradients, III.

Scandinavian Journal of Psychology 8: 33 – [rSG] Bergström, S. () A note on the neural unit model for contrast : G.J. Dalenoort. Gradient representation and perception in the early visual system—A novel account of Mach band formation Article in Vision Research 46(17). Neural Networks for Perception, Volume 2: Computation, Learning, and Architectures explores the computational and adaptation problems related to the use of neuronal systems, and the corresponding hardware architectures capable of implementing neural networks for perception and of coping with the complexity inherent in massively distributed Edition: 1.

A Neural Network Gradients We consider a neural network f θ(), with parameters θ. We maximize the likelihood (8), with respect to the parameters θ, using stochastic gradient. By negating the likelihood, we now assume it corresponds to mini-mize a cost C(f θ()), with respect to θ.

Following the classical “back-propagation” deriva. A Neural Network Model of 3-D Lightness Perception T-junction cells detect such configurations in the image. For example, Iij = Zi-d,j x Zi+d,j x Zi,j+d, (2) where d is a constant, detects T-junctions, where left, right, and top positions of the boundary stage are active; similar cells detect T-junctions of different orientations.

The idea that specific neural activity patterns are caused by specific outside stimuli, such that observing the neural activity allows us to infer the outside stimulus Naïve Template Theory Idea that the visual system recognizes objects by matching the neural representation of the image with a stored representation of the same "shape" in the brain.

Neural Networks It is from this perspective that we will approach neural networks. A general two layer feedforward neural network is given by: y k(x;w) = ˙ 0 @ XM j=0 w(2) kj h XD i=0 w(1) ji x i!1 A Given what we have just covered, if given as set of targets t = [t 1 t n] and a set of inputs X = [x 1 x n] one should.

GRE Psychology- Sensation and Perception. STUDY. PLAY. Ernst Weber. Published book = investigation of muscle sense Introduced the notion of just noticeable difference in sensation.

Details Neural unit in the perception of luminance gradients. PDF

Gustav Fechner. Psychophysics researcher Discovered relationship between physical stimuli and psychological response to stimuli. The human body, like the human face, is a rich source of socially relevant information about other individuals.

Evidence from studies of both humans and non-human primates points to focal regions Cited by: Multisensory integration, also known as multimodal integration, is the study of how information from the different sensory modalities (such as sight, sound, touch, smell, self-motion, and taste) may be integrated by the nervous system.

A coherent representation of objects combining modalities enables animals to have meaningful perceptual experiences.

Description Neural unit in the perception of luminance gradients. PDF

Blutner/Colour/Colour Perception 18 Section through wavelength micture space A section through wavelength mixture space hat forms ant equilateral triangle with the axes. This corresponds to A+B+C=constant and is appropriate to represent the two chromatic values (due tohue and saturation) and fixing Size: 1MB.

The Human Eye. Human Brightness Perception. It is a fact that the eye discriminates intensity in a logarithmic fashion. This is unlike a semiconductor sensor, that discriminates in linear fashion.

The eye's behaviour follows Stanley Smith Stevens' Power Law for human stimulus magnitude perception and varies as the cube root footnote is, that a human would subjectively rate.

Individual neurons in the cortex can make o connections with other brain cells. The precise pattern of connections between a local group of neurons in the cortex gives rises to its elementary unit of computation - the cortical microcircuit. The goal of our laboratory is to reveal the neural basis of perception.

The book opens with two broad, introductory level reviews on the themes of the book: neural networks as tools to explore the nature of perceptual mechanisms, and neural networks as models of perception in ecology and evolutionary biology.

Later chapters expand on these themes and address important methodological issues when applying artificial.

The luminance and colour gradients across an image are the result of complex interactions between object shape, material and illumination.

Using such variations to infer object shape or surface colour is therefore a difficult problem for the visual system. We know that changes to the shape of an object can affect its perceived colour, and that shading gradients confer a sense. The publication of Katz's (, ) book The World of Colour gave enormous momentum to the emerging field of lightness perception.

“Its importance at the time of its publication can hardly be overrated,” wrote Koffka (, p. ).Katz presented a thorough phenomenological analysis of the visual experience of color. He outlined the various modes of color appearance, Cited by: Vision: Images, Signals and Neural Networks - Models of Neural Processing in Visual Perception (Progress in Neural Processing) 1st Edition.

by Jeanny Herault (Author) ISBN ISBN Why is ISBN important. ISBN. This bar-code number lets you verify that you're getting exactly the right version or edition of a book.

Cited by: 9. Author summary Objects in our visual world contain a variety of material information. Although such information enables us to experience rich material impressions, it can be a distraction for the estimation of other physical properties such as shapes, albedos, and illuminations.

The coupled estimation of these properties we humans perform in daily situations is one of the fundamental Cited by: PSY Outline. Note: The class has 15 weeks. Exams happen during weeks 5, 10 & 15, and are paired with a review day.

Perception is a guessing game. Neural responses representing luminance boundaries are more credible that neural responses representing uniform patches (because adaptation makes it impossible to make absolute lightness. It is well known that visible luminance gradients may generate contrast effects.

In this work we present a new paradoxical illusion in which the luminance range of gradual transitions has been reduced to make them invisible. By adopting the phenomenological method proposed by Kanizsa, we have found that unnoticeable luminance gradients still generate .