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1	Estimation of cortical magnification from positional error in normally sighted and amblyopic subjects Hussain, Z., Svensson, C-M., Besle, J., Webb, B.S., Barrett, Brendan T., McGraw, Paul V. 02 1900 (has links) Yes / We describe a method for deriving the linear cortical magnification factor from positional error across the visual field. We compared magnification obtained from this method between normally sighted individuals and amblyopic individuals, who receive atypical visual input during development. The cortical magnification factor was derived for each subject from positional error at 32 locations in the visual field, using an established model of conformal mapping between retinal and cortical coordinates. Magnification of the normally sighted group matched estimates from previous physiological and neuroimaging studies in humans, confirming the validity of the approach. The estimate of magnification for the amblyopic group was significantly lower than the normal group: by 4.4 mm deg 1 at 18 eccentricity, assuming a constant scaling factor for both groups. These estimates, if correct, suggest a role for early visual experience in establishing retinotopic mapping in cortex. We discuss the implications of altered cortical magnification for cortical size, and consider other neural changes that may account for the amblyopic results. Cortical magnification Estimation Positional error Normally sighted Amblyopic individuals
2	Organisation rétinotopique des structures visuelles révélée par imagerie optique cérébrale chez le rat normal Nassim, Marouane January 2008 (has links) Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal. Acuity Continuous stimulation Cortical magnification factors Fourier analysis Mayer waves Optical imagery Primary visual cortex Retinotopic organization Superior colliculus Vascular noise Acuité Analyse de Fourier Bruit vasculaire Collicule supérieure Cortex visuelle primaire Facteur cortical de grossissement Imagerie optique Ondes de Mayer Organisation rétinotopique Stimulation continue
3	Organisation rétinotopique des structures visuelles révélée par imagerie optique cérébrale chez le rat normal Nassim, Marouane January 2008 (has links) Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal Acuity Continuous stimulation Cortical magnification factors Fourier analysis Mayer waves Optical imagery Primary visual cortex Retinotopic organization Superior colliculus Vascular noise Acuité Analyse de Fourier Bruit vasculaire Collicule supérieure Cortex visuelle primaire Facteur cortical de grossissement Imagerie optique Ondes de Mayer Organisation rétinotopique Stimulation continue

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