Toggle Main Menu Toggle Search

ePrints

Spatial non-homogeneity of the antagonistic surround in motion perception

Lookup NU author(s): Dr Ignacio Serrano-Pedraza, Ellen Hogg, Professor Jenny Read

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

At high contrast, duration thresholds for motion direction discrimination deteriorate with increasing stimulus size. This counterintuitive result has been explained by the center-surround antagonism present in the neurons of visual area MT. Conversely, at very low contrast, direction discrimination improves with increasing size, a result that has been explained by spatial summation. In this investigation, we study the effects of stimulus shape and contrast on center-surround antagonism. Using adaptive Bayesian staircases, we measured duration thresholds of 5 subjects for vertically oriented Gabor patches of 1 cycle/deg with two types of oval Gaussian windows, one vertically elongated (Sx = 0.35, Sy = 2.5 deg) and other horizontally elongated (Sx = 2.5, Sy = 0.35 deg) moving rightward or leftward at a speed of 2 deg/s. We found that at high contrast (92%) duration thresholds were lower for vertically than horizontally elongated windows. However, at low contrast (2.8%), we found that duration thresholds were lower for horizontally than vertically elongated windows. These asymmetric results mirror the spatial non-homogeneity of the antagonistic surround found in MT neurons and suggest that the underlying center-surround antagonism is stronger along the direction of motion.


Publication metadata

Author(s): Serrano-Pedraza I, Hogg EL, Read JCA

Publication type: Article

Publication status: Published

Journal: Journal of Vision

Year: 2011

Volume: 11

Issue: 2

Pages: 3

Print publication date: 03/02/2011

ISSN (electronic): 1534-7362

Publisher: Association for Research in Vision and Ophthalmology

URL: http://dx.doi.org/10.1167/11.2.3

DOI: 10.1167/11.2.3

Notes: Article no. 3


Altmetrics

Altmetrics provided by Altmetric


Actions

    Link to this publication


Share