What can we learn about the visual cortex from retinal lesions?

Abstract

Event Abstract Back to Event What can we learn about the visual cortex from retinal lesions? Ulf T. Eysel1* and Dimitrios V. Giannikopoulos1 1 Ruhr University, Department of Neurophysiology, Germany Binocular central retinal lesions induce a lesion projection zone (LPZ) with complete loss of visual excitability followed by extensive reorganization in the cat primary visual cortex. In how far can functional single cell properties be restored during the lesion-induced reorganization process in adulthood? We studied the dynamics of reorganization in the LPZ by single cell recordings with special emphasis on receptive field size (RF), orientation (OS) and direction selectivity (DS) over a period of one year in adult cats. Inside the LPZ the percentage of reactivated cells increased with time, and after 1 year reactivation spanned a total distance of more than 3.5 mm from the border towards the center of the LPZ. New visually responsive single cells had exceptionally large RFs, reduced sharpness of OS and supernormal DS surprisingly biased to directions centrifugal from the center of the LPZ. The initially very large RFs recovered to sizes as normally present at the border of the central retinal lesion, while the fine grain resolution obtained in controls with normal input from the central retina was never reestablished. OS did not recover at all, it decreased in quality inside the LPZ with distance from the border (Giannikopoulos and Eysel, 2006). The centrifugal bias of DS remained up to 12 months, however, after 2 weeks the strength of DS returned to and stayed normal inside the LPZ close to the border (up to 0.5 mm). 2 mm further inside normal values were observed at 12 weeks, but subnormal DS strength prevailed within the LPZ after 1 year. In summary, the long-ranging reactivation of single cells inside the LPZ in cat visual cortex is accompanied by reductions of functional specificity that can only partially or not at all be compensated by the adult plasticity of lateral connections and intracortical computations. Subcortical input appears most crucial for OS. RF can be restored best and appears most robust after reorganization. Supported by the DFG (SFB 509). Conference: IBRO International Workshop 2010, Pécs, Hungary, 21 Jan - 23 Jan, 2010. Presentation Type: Oral Presentation Topic: Vision: from the evolution of retinas to the evolution of ideas Citation: Eysel UT and Giannikopoulos DV (2010). What can we learn about the visual cortex from retinal lesions?. Front. Neurosci. Conference Abstract: IBRO International Workshop 2010. doi: 10.3389/conf.fnins.2010.10.00250 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 05 May 2010; Published Online: 05 May 2010. * Correspondence: Ulf T Eysel, Ruhr University, Department of Neurophysiology, Bochum, Germany, eysel@rub.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Ulf T Eysel Dimitrios V Giannikopoulos Google Ulf T Eysel Dimitrios V Giannikopoulos Google Scholar Ulf T Eysel Dimitrios V Giannikopoulos PubMed Ulf T Eysel Dimitrios V Giannikopoulos Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.