Skip to main content

Research Repository

See what's under the surface

Advanced Search

Perceptual learning reduces crowding in amblyopia and in the normal periphery

Hussain, Zahra; Webb, Ben S.; Astle, Andrew T.; McGraw, Paul V.

Authors

Zahra Hussain

Ben S. Webb

Andrew T. Astle andrew.astle@nottingham.ac.uk

Paul V. McGraw



Abstract

Amblyopia is a developmental visual disorder of cortical origin, characterized by crowding and poor acuity in central vision of the affected eye. Crowding refers to the adverse effects of surrounding items on object identification, common only in normal peripheral but not central vision. We trained a group of adult human amblyopes on a crowded letter identification task to assess whether the crowding problem can be ameliorated. Letter size was fixed well above the acuity limit, and letter spacing was varied to obtain spacing thresholds for central target identification. Normally sighted observers practiced the same task in their lower peripheral visual field. Independent measures of acuity were taken in flanked and unflanked conditions before and after training to measure crowding ratios at three fixed letter separations. Practice improved the letter spacing thresholds of both groups on the training task, and crowding ratios were reduced after posttest. The reductions in crowding in amblyopes were associated with improvements in standard measures of visual acuity. Thus, perceptual learning reduced the deleterious effects of crowding in amblyopia and in the normal periphery. The results support the effectiveness of plasticity-based approaches for improving vision in adult amblyopes and suggest experience-dependent effects on the cortical substrates of crowding.

Journal Article Type Article
Publication Date Jan 1, 2012
Journal Journal of Neuroscience
Electronic ISSN 1529-2401
Publisher Society for Neuroscience
Peer Reviewed Peer Reviewed
Volume 32
Issue 2
APA6 Citation Hussain, Z., Webb, B. S., Astle, A. T., & McGraw, P. V. (2012). Perceptual learning reduces crowding in amblyopia and in the normal periphery. Journal of Neuroscience, 32(2), doi:10.1523/JNEUROSCI.3845-11.2012
DOI https://doi.org/10.1523/JNEUROSCI.3845-11.2012
Publisher URL http://jneurosci.org/content/32/2/474.short
Copyright Statement Copyright information regarding this work can be found at the following address: http://creativecommons.org/licenses/by/4.0

Files

474 full.pdf (1.3 Mb)
PDF

Copyright Statement
Copyright information regarding this work can be found at the following address: http://creativecommons.org/licenses/by/4.0





You might also like



Downloadable Citations

;