The relationship between retinal cone density and cortical magnification in human albinism. J Vis 2020 Jun 03;20(6):10
Date
06/17/2020Pubmed ID
32543650Pubmed Central ID
PMC7416892DOI
10.1167/jov.20.6.10Scopus ID
2-s2.0-85086624344 (requires institutional sign-in at Scopus site) 11 CitationsAbstract
The human fovea lies at the center of the retina and supports high-acuity vision. In normal visual system development, the highest acuity is correlated with both a high density of cone photoreceptors in the fovea and a magnified retinotopic representation of the fovea in the visual cortex. Both cone density and the cortical area dedicated to each degree of visual space-the latter describing cortical magnification (CM)-steadily decrease with increasing eccentricity from the fovea. In albinism, peak cone density at the fovea and visual acuity are decreased, but seem to be within normal limits in the periphery, thus providing a model to explore the correlation between retinal structure, cortical structure, and behavior. Here, we used adaptive optics scanning light ophthalmoscopy to assess retinal cone density and functional magnetic resonance imaging to measure CM in the primary visual cortex of normal controls and individuals with albinism. We find that retinotopic organization is more varied among individuals with albinism than previously appreciated. Additionally, CM outside the fovea is similar to that in controls, but also more variable. CM in albinism and controls exceeds that which might be predicted based on cone density alone, but is more accurately predicted by retinal ganglion cell density. This finding suggests that decreased foveal cone density in albinism may be partially counteracted by nonuniform connectivity between cones and their downstream signaling partners. Together, these results emphasize that central as well as retinal factors must be included to provide a complete picture of aberrant structure and function in albinism.
Author List
Woertz EN, Wilk MA, Duwell EJ, Mathis JR, Carroll J, DeYoe EAAuthors
Joseph J. Carroll PhD Director, Professor in the Ophthalmology department at Medical College of WisconsinEthan J. Duwell Postdoctoral Researcher 4 in the Biomedical Engineering department at Medical College of Wisconsin
Erica Woertz in the CTSI department at Medical College of Wisconsin - CTSI
MESH terms used to index this publication - Major topics in bold
AdolescentAdult
Albinism
Cell Count
Female
Humans
Magnetic Resonance Imaging
Male
Ophthalmoscopy
Optics and Photonics
Retina
Retinal Cone Photoreceptor Cells
Retinal Ganglion Cells
Visual Acuity
Visual Cortex
Young Adult
