Contrast masking in strabismic amblyopia: attenuation, noise, interocular suppression and binocular summation

Daniel H. Baker, Timothy S. Meese, Robert F. Hess

Research output: Contribution to journalArticle

Abstract

To investigate amblyopic contrast vision at threshold and above we performed pedestal-masking (contrastdiscrimination) experiments with a group of eight strabismic amblyopes using horizontal sinusoidal gratings (mainly 3 c/deg) in monocular, binocular and dichoptic configurations balanced across eye (i.e. five conditions). With some exceptions in some observers, the four main results were as follows. (1) For the monocular and dichoptic conditions, sensitivity was less in the amblyopic eye than in the good eye at all mask contrasts. (2) Binocular and monocular dipper functions superimposed in the good eye. (3) Monocular masking functions had a normal dipper shape in the good eye, but facilitation was diminished in the amblyopic eye. (4) A less consistent result was normal facilitation in dichoptic masking when testing the good eye, but a loss of this when testing the amblyopic eye. This pattern of amblyopic results was replicated in a normal observer by placing a neutral density filter in front of one eye. The two-stage model of binocular contrast gain control [Meese, T.S., Georgeson, M.A. & Baker, D.H. (2006). Binocular contrast vision at and above threshold. Journal of Vision 6, 1224--1243.] was `lesioned' in several ways to assess the form of the amblyopic deficit. The most successful model involves attenuation of signal and an increase in noise in the amblyopic eye, and intact stages of interocular suppression and binocular summation. This implies a behavioural influence from monocular noise in the amblyopic visual system as well as in normal observers with an ND filter over one eye.
Original languageEnglish
Pages (from-to)1625-1640
Number of pages16
JournalVision Research
Volume48
Issue number15
DOIs
Publication statusPublished - 10 Jun 2008

Fingerprint

Amblyopia
Noise
Binocular Vision
Masks

Bibliographical note

NOTICE: this is the author’s version of a work that was accepted for publication in Vision Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Baker, Daniel H.; Meese, Timothy S. and Hess, Robert F. (2008). Contrast masking in strabismic amblyopia: attenuation, noise, interocular suppression and binocular summation. Vision Research, 48 (15), pp. 1625-1640. DOI 10.1016/j.visres.2008.04.017

Keywords

  • human vision
  • amblyopia
  • strabismus
  • masking
  • contrast discrimination
  • noise

Cite this

@article{8877e3f88806498686d975a6eba38328,
title = "Contrast masking in strabismic amblyopia: attenuation, noise, interocular suppression and binocular summation",
abstract = "To investigate amblyopic contrast vision at threshold and above we performed pedestal-masking (contrastdiscrimination) experiments with a group of eight strabismic amblyopes using horizontal sinusoidal gratings (mainly 3 c/deg) in monocular, binocular and dichoptic configurations balanced across eye (i.e. five conditions). With some exceptions in some observers, the four main results were as follows. (1) For the monocular and dichoptic conditions, sensitivity was less in the amblyopic eye than in the good eye at all mask contrasts. (2) Binocular and monocular dipper functions superimposed in the good eye. (3) Monocular masking functions had a normal dipper shape in the good eye, but facilitation was diminished in the amblyopic eye. (4) A less consistent result was normal facilitation in dichoptic masking when testing the good eye, but a loss of this when testing the amblyopic eye. This pattern of amblyopic results was replicated in a normal observer by placing a neutral density filter in front of one eye. The two-stage model of binocular contrast gain control [Meese, T.S., Georgeson, M.A. & Baker, D.H. (2006). Binocular contrast vision at and above threshold. Journal of Vision 6, 1224--1243.] was `lesioned' in several ways to assess the form of the amblyopic deficit. The most successful model involves attenuation of signal and an increase in noise in the amblyopic eye, and intact stages of interocular suppression and binocular summation. This implies a behavioural influence from monocular noise in the amblyopic visual system as well as in normal observers with an ND filter over one eye.",
keywords = "human vision, amblyopia, strabismus, masking, contrast discrimination, noise",
author = "Baker, {Daniel H.} and Meese, {Timothy S.} and Hess, {Robert F.}",
note = "NOTICE: this is the author’s version of a work that was accepted for publication in Vision Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Baker, Daniel H.; Meese, Timothy S. and Hess, Robert F. (2008). Contrast masking in strabismic amblyopia: attenuation, noise, interocular suppression and binocular summation. Vision Research, 48 (15), pp. 1625-1640. DOI 10.1016/j.visres.2008.04.017",
year = "2008",
month = "6",
day = "10",
doi = "10.1016/j.visres.2008.04.017",
language = "English",
volume = "48",
pages = "1625--1640",
journal = "Vision Research",
issn = "0042-6989",
publisher = "Elsevier",
number = "15",

}

Contrast masking in strabismic amblyopia: attenuation, noise, interocular suppression and binocular summation. / Baker, Daniel H.; Meese, Timothy S.; Hess, Robert F.

In: Vision Research, Vol. 48, No. 15, 10.06.2008, p. 1625-1640.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Contrast masking in strabismic amblyopia: attenuation, noise, interocular suppression and binocular summation

AU - Baker, Daniel H.

AU - Meese, Timothy S.

AU - Hess, Robert F.

N1 - NOTICE: this is the author’s version of a work that was accepted for publication in Vision Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Baker, Daniel H.; Meese, Timothy S. and Hess, Robert F. (2008). Contrast masking in strabismic amblyopia: attenuation, noise, interocular suppression and binocular summation. Vision Research, 48 (15), pp. 1625-1640. DOI 10.1016/j.visres.2008.04.017

PY - 2008/6/10

Y1 - 2008/6/10

N2 - To investigate amblyopic contrast vision at threshold and above we performed pedestal-masking (contrastdiscrimination) experiments with a group of eight strabismic amblyopes using horizontal sinusoidal gratings (mainly 3 c/deg) in monocular, binocular and dichoptic configurations balanced across eye (i.e. five conditions). With some exceptions in some observers, the four main results were as follows. (1) For the monocular and dichoptic conditions, sensitivity was less in the amblyopic eye than in the good eye at all mask contrasts. (2) Binocular and monocular dipper functions superimposed in the good eye. (3) Monocular masking functions had a normal dipper shape in the good eye, but facilitation was diminished in the amblyopic eye. (4) A less consistent result was normal facilitation in dichoptic masking when testing the good eye, but a loss of this when testing the amblyopic eye. This pattern of amblyopic results was replicated in a normal observer by placing a neutral density filter in front of one eye. The two-stage model of binocular contrast gain control [Meese, T.S., Georgeson, M.A. & Baker, D.H. (2006). Binocular contrast vision at and above threshold. Journal of Vision 6, 1224--1243.] was `lesioned' in several ways to assess the form of the amblyopic deficit. The most successful model involves attenuation of signal and an increase in noise in the amblyopic eye, and intact stages of interocular suppression and binocular summation. This implies a behavioural influence from monocular noise in the amblyopic visual system as well as in normal observers with an ND filter over one eye.

AB - To investigate amblyopic contrast vision at threshold and above we performed pedestal-masking (contrastdiscrimination) experiments with a group of eight strabismic amblyopes using horizontal sinusoidal gratings (mainly 3 c/deg) in monocular, binocular and dichoptic configurations balanced across eye (i.e. five conditions). With some exceptions in some observers, the four main results were as follows. (1) For the monocular and dichoptic conditions, sensitivity was less in the amblyopic eye than in the good eye at all mask contrasts. (2) Binocular and monocular dipper functions superimposed in the good eye. (3) Monocular masking functions had a normal dipper shape in the good eye, but facilitation was diminished in the amblyopic eye. (4) A less consistent result was normal facilitation in dichoptic masking when testing the good eye, but a loss of this when testing the amblyopic eye. This pattern of amblyopic results was replicated in a normal observer by placing a neutral density filter in front of one eye. The two-stage model of binocular contrast gain control [Meese, T.S., Georgeson, M.A. & Baker, D.H. (2006). Binocular contrast vision at and above threshold. Journal of Vision 6, 1224--1243.] was `lesioned' in several ways to assess the form of the amblyopic deficit. The most successful model involves attenuation of signal and an increase in noise in the amblyopic eye, and intact stages of interocular suppression and binocular summation. This implies a behavioural influence from monocular noise in the amblyopic visual system as well as in normal observers with an ND filter over one eye.

KW - human vision

KW - amblyopia

KW - strabismus

KW - masking

KW - contrast discrimination

KW - noise

UR - http://www.scopus.com/inward/record.url?scp=45849100482&partnerID=8YFLogxK

U2 - 10.1016/j.visres.2008.04.017

DO - 10.1016/j.visres.2008.04.017

M3 - Article

VL - 48

SP - 1625

EP - 1640

JO - Vision Research

JF - Vision Research

SN - 0042-6989

IS - 15

ER -