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Journal ArticleDOI

Visual function: the problem with eccentricity.

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TLDR
This brief review of the extensive literature on reading with peripheral vision and the research aimed at better reading rehabilitation for low vision patients focuses on why many of the problems associated with the reduced reading capability of peripheral vision cannot be completely solved with magnification, reducing eye movements or modifying print.
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries. With an ageing population, the prevalence of such a condition has resulted in a large proportion of the population relying on peripheral vision to undertake activities of daily living. Peripheral vision is not a scaled-down version of the fovea, simply requiring larger print or increased contrast for detection of objects or reading text. Even when print size is scaled and eye movements are minimised, the peripheral retina cannot perform at the level of the foveal region. Understanding how and why reading performance is limited as a function of eccentricity has important implications for how we approach rehabilitation of patients with central visual loss. This brief review of the extensive literature on reading with peripheral vision and the research aimed at better reading rehabilitation for low vision patients focuses on why many of the problems associated with the reduced reading capability of peripheral vision cannot be completely solved with magnification, reducing eye movements or modifying print.

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Citations
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Visual requirements for reading

TL;DR: The research indicates that fluent reading rates can be attained with a restricted field of view, as little as four characters, however, attainment of fluent reading levels requires that print size and contrast should be several times threshold and the diameter of a central scotoma should be less than 22°.
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Crowding and eccentricity determine reading rate.

TL;DR: It is shown that Legge's visual span is the uncrowded span predicted by Bouma's law, and this result joins Bouma and Legge to explain reading rate's dependence on letter size and spacing.

The design and use of a new near-vision chart

TL;DR: In this article, a logarithmic progression of print size on these charts can be used to facilitate prediction of the magnitude of changes in visual performance resulting from changes in optical parameters.
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Two-Dimensional Mapping of the Central and Parafoveal Visual Field to Human Visual Cortex

TL;DR: This work used functional magnetic resonance imaging (fMRI) to measure the mapping geometry of human V1 and V2 down to 0.5 degrees of eccentricity and proposes that V2 has systematic intrinsic curvature, but V1 is intrinsically flat.

Reading with simulated scotomas: attending to the right is better than attending to the left

TL;DR: Patients with central field loss must learn to read using eccentric retina would be better off with PRL to the right of their scotoma than to the left for the purposes of reading, according to data tested.
References
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Journal ArticleDOI

Human photoreceptor topography

TL;DR: The total number of foveal cones is similar for eyes with widely varying peak cone density, consistent with the idea that the variability reflects differences in the lateral migration of photoreceptors during development.
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Topography of ganglion cells in human retina.

TL;DR: The spatial distribution of presumed ganglion cells and displaced amacrine cells in unstained whole mounts of six young normal human retinas whose photoreceptor distributions had previously been characterized was quantified, suggesting meridianal differences in convergence onto individual ganglION cells.
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Interaction effects in parafoveal letter recognition.

H Herman Bouma
- 11 Apr 1970 - 
TL;DR: Property of the visual system, as well as the reader's knowledge of the language, must be relevant in order for the information in the text to be relevant.
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Visual acuity and the causes of visual loss in Australia. The Blue Mountains Eye Study.

TL;DR: The Blue Mountains Eye Study as discussed by the authors measured the logarithm of the minimum angle of resolution (logMAR) visual acuity in 3647 persons, representing an 88% response rate in two postcode areas in the Blue Mountains area, west of Sydney.
Journal Article

Photoreceptor loss in age-related macular degeneration.

TL;DR: Photoreceptors are lost in NE-AMD as well as in the more severe exudative form, consistent with functional and clinical studies, and the authors propose that rods die in older eyes without evidence of overt retinal pigment epithelial disease.