Psychophysical evidence for two routes to suppression before binocular summation of signals in human vision


Baker, D.H., Meese, T.S. and Summers, R.J. (2007) Psychophysical evidence for two routes to suppression before binocular summation of signals in human vision. Neuroscience, 146, (1), 435-448. (doi:10.1016/j.neuroscience.2007.01.030).

This is the latest version of this item.

Download

[img] PDF - Post print
Download (1323Kb)

Description/Abstract

Visual mechanisms in primary visual cortex are suppressed by the superposition of gratings perpendicular to their preferred orientations. A clear picture of this process is needed to (i) inform functional architecture of image-processing models, (ii) identify the pathways available to support binocular rivalry, and (iii) generally advance our understanding of early vision. Here we use monoptic sine-wave gratings and cross-orientation masking (XOM) to reveal two cross-oriented suppressive pathways in humans, both of which occur before full binocular summation of signals. One is a within-eye (ipsiocular) pathway that is spatially broadband, immune to contrast adaptation and has a suppressive weight that tends to decrease with stimulus duration. The other pathway operates between the eyes (interocular), is spatially tuned, desensitizes with contrast adaptation and has a suppressive weight that increases with stimulus duration. When cross-oriented masks are presented to both eyes, masking is enhanced or diminished for conditions in which either ipsiocular or interocular pathways dominate masking, respectively. We propose that ipsiocular suppression precedes the influence of interocular suppression and tentatively associate the two effects with the lateral geniculate nucleus (or retina) and the visual cortex respectively. The interocular route is a good candidate for the initial pathway involved in binocular rivalry and predicts that interocular cross-orientation suppression should be found in cortical cells with predominantly ipsiocular drive.

Item Type: Article
ISSNs: 0306-4522 (print)
Related URLs:
Keywords: human vision, psychophysics, cross-orientation inhibition, contrast gain control, masking, binocular rivalry
Subjects: R Medicine > RE Ophthalmology
R Medicine > RC Internal medicine > RC0321 Neuroscience. Biological psychiatry. Neuropsychiatry
B Philosophy. Psychology. Religion > BF Psychology
Divisions: University Structure - Pre August 2011 > School of Psychology > Division of Cognition
ePrint ID: 47919
Date Deposited: 09 Aug 2007
Last Modified: 27 Mar 2014 18:31
URI: http://eprints.soton.ac.uk/id/eprint/47919

Available Versions of this Item

Actions (login required)

View Item View Item

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics