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                                                    Visual Neuroscience

                                                    Article contents

                                                    The human retina has a cone-enriched rim

                                                    Published online by Cambridge University Press:  02 June 2009

                                                    Robert W. Williams
                                                    Robert W. Williams
                                                    Affiliation:
                                                    Department of Anatomy and Neurobiology, University of Tennessee, College of Medicine, Memphis
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                                                    Abstract

                                                    Video-enhanced imaging of retinal wholemounts reveals an abrupt change in the composition of the photoreceptor mosaic at the edge of the human retina. Cone densities rise threefold and rod densities fall tenfold in a 1-mm-wide peripheral band. Antibodies directed against cones confirm the identification of the major subtypes of photoreceptors within this peripheral band. The cone-enriched rim is most highly developed along the nasal retinal margin, an area where the extreme lateral periphery of the visual field is imaged. This rim of cones may function as part of a rapid-acting alert mechanism under conditions of moderate and bright illumination.

                                                    Keywords

                                                    Human retinaCone densityCone-enriched rimRod densityOra serrata

                                                    Information

                                                    Type
                                                    Rapid Communication
                                                    Information
                                                    Visual Neuroscience , Volume 6 , Issue 4 , April 1991 , pp. 403 - 406
                                                    Copyright
                                                    Copyright © Cambridge University Press 1991

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