 |
| Research article summary (published 29 Sep 2002): |
Visual depth encoding in populations of neurons with localized receptive fields.
Full Abstract
Stereopsis is the ability to perceive three-dimensional structure from disparities between the two-dimensional retinal images. Although disparity-sensitive neurons have been proposed as a neural representation of this ability many years ago, it is still difficult to link all qualities of stereopsis to properties of the neural correlate of binocular disparities. The present study wants to support efforts directed at closing the gap between electrophysiology and psychophysics. Populations of disparity-sensitive neurons in V1 were simulated using the energy-neuron model. Responses to different types of stimuli were evaluated with an efficient statistical estimator and related to psychophysical findings. The representation of disparity in simulated population responses appeared to be very robust. Small populations allowed good depth discrimination. Two types of energy neurons (phase- and position-type models) that are discussed as possible neural implementations of disparity-selectivity could be compared to each other. Phase-type coding was more robust and could explain a tendency towards zero disparity in degenerated stimuli and, for high-pass stimuli, exhibited the breakdown of disparity discrimination at a maximum disparity value. Contrast-inverted stereograms led to high variances in disparity representation, which is a possible explanation of the absence of depth percepts in large contrast-inverted stimuli. Our study suggests that nonlocal interactions destroy depth percepts in large contrast-inverted stereograms, although these percepts occur for smaller stimuli of the same class.
Learn Faster Today Improve your study skills
Author information
Author/s: Lippert, Jörg (J); Wagner, Hermann (H);
Affiliation: Institut für Biologie II, RWTH Aachen, Kopernikusstr 16, 52074 Aachen, Germany. joerg.lippert.jl(-atsign-)bayer-ag.de
Journal and publication information
Publication Type: Journal Article; Research Support, Non-U.S. Gov't
Journal: Biological cybernetics (Biol Cybern), published in Germany. (Language: eng)
Reference: 2002-Oct; vol 87 (issue 4) : pp 249-61
Dates: Created 2002/10/18; Completed 2003/06/18; Revised 2006/11/15;
PMID: 12386741, status: MEDLINE (last retrieval date: 11/6/2008)
Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.
External Links for this article (including full text providers, if available):
Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.
This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.
MeSH headings (categories)
This article was linked to the MESH Headings shown below.
|
|
Related articles
This article has not been indexed for related articles as yet, however you can still use the live related article search links below.
See a large map of 100+ related articles.