Identification of 3D shape from texture and motion across the visual field.

Full Abstract

Little is known about the perception of 3D shape in the visual periphery. Here we ask whether identification accuracy in shape-from-texture and shape-from-motion tasks can be equated across the visual field with sufficient stimulus magnification. Both tasks employed 3D surfaces comprising hills, valleys, and plains in three possible locations, yielding a 27 alternative forced-choice task (27AFC). Participants performed the task at eccentricities of 0 to 16 deg in the right visual field over a 64-fold range of stimulus sizes. Performance reached ceiling levels at all eccentricities, indicating that stimulus magnification was sufficient to compensate for eccentricity-dependent sensitivity loss. The parameter E(2) (in the equation F = 1 + E / E(2)) was used to characterize the rate at which stimulus size must increase with eccentricity (E) to achieve foveal levels of performance. Three parameter models (mu, sigma, and E(2)) captured most of the variability in the psychometric functions relating stimulus size and eccentricity to accuracy for all participants' data in the two experiments. For the shape-from-texture task, the average E(2) was 1.52, and for the shape-from-motion task, it was 0.61. The E(2) values indicate that sensitivity to structure from motion declines at a faster rate with eccentricity than does sensitivity to structure from texture. Although size scaling with F = 1 + E / E(2) eliminated most eccentricity variation from the structure-from-motion data, there was some evidence that E(2) increases as accuracy decreases in the shape-from-texture task, suggesting that there may be more than one eccentricity-dependent limitation on performance in this task.

Learn Faster Today Improve your study skills

Author information

Author/s: Gurnsey, Rick (R); Poirier, Frédéric J A M (FJ); Bluett, Patricia (P); Leibov, Laurie (L);

Affiliation: Department of Psychology, Concordia University, Montreal, QC, Canada. Rick.Gurnsey(-atsign-)concordia.ca

Journal and publication information

Publication Type: Journal Article; Research Support, Non-U.S. Gov't

Journal: Journal of vision (J Vis), published in United States. (Language: eng)

Reference: 2006-; vol 6 (issue 5) : pp 543-53

Dates: Created 2006/08/02; Completed 2006/08/31; Revised 2008/04/29;

PMID: 16881787, status: MEDLINE (last retrieval date: 12/26/2008)

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.

These are the highest related articles currently in the database:

Rotation direction affects object recognition. 30 Dec 2003
The relative capabilities of the upper and lower visual hemifields. 29 Sep 2005
Psychophysics with junctions in real images. 30 Dec 2003
Neural correlates of shape-from-shading. 27 Feb 2006
Relative sensitivities to large-field optic-flow patterns varying in direction and speed. 30 Dec 2006
Induced motion in depth and the effects of vergence eye movements. 10 Mar 2008
Effective binocular integration at the midline requires the corpus callosum. 30 Dec 2003
Interaction between luminance gratings and disparity gratings. 30 Dec 2003
Effects of spatial arrangement of visual stimulus on inverted self-motion perception induced by the foreground motion: examination of OKN-suppression hypothesis. 30 Dec 2003
Sensitivity to linear-speed-gradient of radial expansion flow in infancy. 29 Nov 2004

See 100+ related articles.