Contrast-modulated stimuli produce more superimposition and predominate perception when competing with comparable luminance-modulated stimuli during interocular grouping

Jan Skerswetat, Monika A. Formankiewicz, Sarah J. Waugh

Research output: Contribution to journalArticlepeer-review

Abstract

Interocular grouping (IOG) is a binocular visual function that can arise during multi-stable perception. IOG perception was initiated using split-grating stimuli constructed from luminance (L), luminance-modulated noise (LM) and contrast-modulated noise (CM). In Experiment 1, three different visibility levels were used for L and LM (or first-order) stimuli, and compared to fixed-visibility CM (or second-order) stimuli. Eight binocularly normal participants indicated whether they perceived full horizontal or vertical gratings, superimposition, or other (piecemeal and eye-of-origin) percepts. CM stimuli rarely generated full IOG, but predominantly generated superimposition. In Experiment 2, Levelt’s modified laws were tested for IOG in nine participants. Split-gratings presented to each eye contained different visibility LM gratings, or LM and CM gratings. The results for the LM-vs-LM conditions mostly followed the predictions of Levelt’s modified laws, whereas the results for the LM-vs-CM conditions did not. Counterintuitively, when high-visibility LM and low-visibility CM split-gratings were used, high-visibility LM components did not predominate IOG perception. Our findings suggest that higher proportions of superimposition during CM-vs-CM viewing are due to binocular combination, rather than mutual inhibition. It implies that IOG percepts are more likely to be mediated at an earlier monocular, rather than a binocular stage. Our previously proposed conceptual framework for conventional binocular rivalry, which includes asymmetric feedback, visual saliency, or a combination of both (Skerswetat et al. Sci Rep 8:14432, 2018), might also account for IOG. We speculate that opponency neurons might mediate coherent percepts when dissimilar information separately enters the eyes.

Original languageEnglish
Article number13409
Number of pages15
JournalScientific Reports
Volume10
Issue number1
Early online date7 Aug 2020
DOIs
Publication statusPublished - 1 Dec 2020
Externally publishedYes

Fingerprint

Dive into the research topics of 'Contrast-modulated stimuli produce more superimposition and predominate perception when competing with comparable luminance-modulated stimuli during interocular grouping'. Together they form a unique fingerprint.

Cite this