Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Symmetry detection across the visual field.

S Sally1, R Gurnsey

  • 1Department of Psychology, Concordia University, Montreal, Quebec, Canada.

Spatial Vision
|July 14, 2001
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Texture space.

Vision research·2001
Same author

Detection and discrimination of subjective contours defined by offset gratings.

Perception & psychophysics·1999
Same author

Bilateral symmetry embedded in noise is detected accurately only at fixation.

Vision research·1999
Same author

Second-order motions contribute to vection.

Vision research·1998
Same author

The effects of eccentricity and spatial frequency on the orientation discrimination asymmetry.

Spatial vision·1998
Same author

Effect of colchicine on chronic ciclosporin nephrotoxicity in Sprague-Dawley rats.

Nephron·1998
Same journal

Comment on 'angle illusion on a picture's surface' by Hammad et al. (2008).

Spatial vision·2009
Same journal

Feature-based attentional modulation increases with stimulus separation in divided-attention tasks.

Spatial vision·2009
Same journal

Spatial distance between target and irrelevant patch modulates detection in a texture segmentation task.

Spatial vision·2009
Same journal

Inhibition related impairments of coherent motion perception in the attention-induced motion blindness paradigm.

Spatial vision·2009
Same journal

Recognition units in reading: backward masking experiments.

Spatial vision·2009
Same journal

Spatial-temporal modeling of interactive image interpretation.

Spatial vision·2009
See all related articles

Human visual sensitivity to symmetry decreases with eccentricity. Scaling stimuli by eccentricity compensates for this loss, with optimal scaling factors (E2) between 0.88 and 1.38 degrees for consistent symmetry detection.

Area of Science:

  • Visual perception
  • Human psychophysics
  • Computational neuroscience

Background:

  • Human visual system exhibits high sensitivity to symmetry in the fovea.
  • Symmetry detection performance declines significantly as stimuli move to the visual periphery.
  • Eccentricity-dependent sensitivity loss necessitates understanding visual scaling principles.

Purpose of the Study:

  • To investigate if magnification can equalize symmetry detection across visual field eccentricities.
  • To determine the optimal stimulus scaling factor (E2) for consistent performance.
  • To assess the impact of stimulus visibility on eccentricity compensation.

Main Methods:

  • A psychophysical study involving symmetry discrimination tasks.
  • Stimuli presented at various sizes and eccentricities (0-8 degrees).

Related Experiment Videos

  • Two experiments: one with maximal contrast, another with contrast equated to detection threshold.

    • Main Results:

    • A unified scaling function effectively reduced eccentricity-related performance variations.
    • The scaling parameter E2, crucial for equalizing performance, ranged from 0.88 to 1.38 degrees.
    • Failure to equate stimulus visibility across eccentricities led to inflated E2 estimates.

    Conclusions:

    • Symmetry detection can be standardized across viewing eccentricities through appropriate stimulus scaling.
    • The parameter E2 provides a quantitative measure for visual scaling in symmetry perception.
    • Controlling for stimulus visibility is critical for accurate estimation of eccentricity compensation parameters.