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

Differences in real and illusory shape perception revealed by backward masking.

Michelle L Imber1, Robert M Shapley, Nava Rubin

  • 1Department of Psychology, New York University, United States. michelle_imber@hms.harvard.edu

Vision Research
|December 2, 2004
PubMed
Summary

Illusory contours (ICs) can mask other ICs at long stimulus onset asynchronies (SOAs), but real contours (RCs) cannot. This suggests different processing levels for ICs and RCs in visual perception.

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

A multiplicity of color-responsive cortical mechanisms revealed by the dynamics of cVEPs.

Vision research·2021
Same author

Distinct spatiotemporal mechanisms underlie extra-classical receptive field modulation in macaque V1 microcircuits.

eLife·2020
Same author

Functional Clusters of Neurons in Layer 6 of Macaque V1.

The Journal of neuroscience : the official journal of the Society for Neuroscience·2020
Same author

Population rate-coding predicts correctly that human sound localization depends on sound intensity.

eLife·2019
Same author

Cortical Double-Opponent Cells in Color Perception: Perceptual Scaling and Chromatic Visual Evoked Potentials.

i-Perception·2018
Same author

Nonlinear dynamics of cortical responses to color in the human cVEP.

Journal of vision·2017

Area of Science:

  • * Visual perception
  • * Cognitive neuroscience

Background:

  • * Illusory contours (ICs) are crucial for perceiving occluded surfaces.
  • * Understanding the distinction between ICs and real contours (RCs) aids in mapping visual processing.
  • * Previous research suggests ICs and RCs may be processed differently.

Purpose of the Study:

  • * To investigate the relationship between real and illusory contour perception.
  • * To determine if ICs and RCs are processed at similar or different levels in the visual system.
  • * To explore the temporal dynamics and characteristics of masking effects for ICs and RCs.

Main Methods:

  • * A shape discrimination task was employed.
  • * A backward masking paradigm was utilized with varying stimulus onset asynchronies (SOAs).

Related Experiment Videos

  • * Both ICs and RCs were used as targets and masks, with varying contrasts and sizes.

    • Main Results:

    • * ICs masked other ICs at long SOAs (approx. 300 ms).
    • * RCs were not effectively masked by ICs or other RCs, even at long SOAs.
    • * Masking between ICs occurred across different target and mask sizes, suggesting higher-level processing.
    • * Masking was absent for RC masks at salient contrasts or when matched to illusory surface brightness.

    Conclusions:

    • * Late masking effects between ICs suggest processing at a higher level than early visual areas.
    • * Differential masking patterns for ICs and RCs indicate distinct neural representations for contour types.
    • * Findings support the hypothesis that shape categories and surfaces are processed at a level sensitive to contour origin (real vs. illusory).