Linear binocular combination of responses to contrast modulation:contrast-weighted summation in first- and second-order vision

Zhou, Jiawei, Georgeson, Mark A. and Hess, Robert F. (2014). Linear binocular combination of responses to contrast modulation:contrast-weighted summation in first- and second-order vision. Journal of Vision, 14 (13),

Abstract

Binocular combination for first-order (luminancedefined) stimuli has been widely studied, but we know rather little about this binocular process for spatial modulations of contrast (second-order stimuli). We used phase-matching and amplitude-matching tasks to assess binocular combination of second-order phase and modulation depth simultaneously. With fixed modulation in one eye, we found that binocularly perceived phase was shifted, and perceived amplitude increased almost linearly as modulation depth in the other eye increased. At larger disparities, the phase shift was larger and the amplitude change was smaller. The degree of interocular correlation of the carriers had no influence. These results can be explained by an initial extraction of the contrast envelopes before binocular combination (consistent with the lack of dependence on carrier correlation) followed by a weighted linear summation of second-order modulations in which the weights (gains) for each eye are driven by the first-order carrier contrasts as previously found for first-order binocular combination. Perceived modulation depth fell markedly with increasing phase disparity unlike previous findings that perceived first-order contrast was almost independent of phase disparity. We present a simple revision to a widely used interocular gain-control theory that unifies first- and second-order binocular summation with a single principle-contrast-weighted summation-and we further elaborate the model for first-order combination. Conclusion: Second-order combination is controlled by first-order contrast.

Publication DOI: https://doi.org/10.1167/14.13.24
Divisions: Life & Health Sciences > Optometry
Life & Health Sciences > Ophthalmic Research Group
Additional Information: © 2014 ARVO Funding: CIHR grant (#53346); NSERC grant (#46528-11); and BBSRC grant (BB/ H00159/X1)
Uncontrolled Keywords: binocular combination,binocular disparity,contrast modulation,contrastgain control,first-order,interocular suppression,rivalry suppression,second-order,Ophthalmology,Sensory Systems,Medicine(all)
Full Text Link:
Related URLs: http://www.scopus.com/inward/record.url?scp=84916228456&partnerID=8YFLogxK (Scopus URL)
Published Date: 2014-11-30
Authors: Zhou, Jiawei
Georgeson, Mark A. ( 0000-0002-8173-9522)
Hess, Robert F.

Download

[img]

Version: Published Version

| Preview

Export / Share Citation


Statistics

Additional statistics for this record