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Formation of new andpermanent retinofugal projections into nonvisual sites including the thalamic auditory nucleus (Frost and Metin, Ptito et al a; Figure A).These surgically induced retinal projections are retinotopically organized and make functional synapses (Metin and Frost,).Neurons within the somatosensory cortex of animals with ectopic retinal projections have visual response properties comparable to those of neurons in the primary visual cortex of typical sighted animals (Metin and Frost,).Ferrets devoid of visual cortex but with retinofugal projections for the auditory thalamus appear to perceive light stimuli as visual (von Melchner et al ).The query concerning the parallelism involving a various brain organization (made by lesions) along with a behavioral recovery is still debated although recent experiments in rewired ferrets and hamsters suggest a big degree PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/21543622 of recovery in visual functions (reviewed in Ptito et al a).As an example, responses to visual stimuli have already been observed inside the auditory cortex of hamsters with robust and permanent projections for the auditory thalamic nucleus (medial geniculate physique) but lacking a visual cortex.Single neurons in the auditory cortex of these animals respond to visual stimuli and a few respond equally properly to visual as to auditory stimuli.Additionally,Figure Behavioral and physiological effects of surgically developed ectopic retinal projections to the auditory cortex in hamsters.(A) Neonatal lesions of principal retinal targets (SC) and subsequent destruction of cortical visual regions (V, V, and Vm) generate a robust projection from the retina to the auditory cortex (AC).(B) Comparison of your distribution of preferred orientations for cells in region V (typical animals) and region A (rewired animals).The auditory cortex in rewired hamsters adopts receptive field properties in the major visual cortex like orientation selectivity.Neurons within A of rewired hamsters respond to horizontal (H), vertical (V), and oblique (O) stimulus orientations.All orientations are represented but with no preference bias for vertical orientations as seen in standard animals and with an elevated number of nonspecific cells (NS).(C) Rewired hamsters find out visual discrimination tasks also as typical animals.In regular animals, a bilateral V lesion abolishes pattern discrimination.The exact same result is obtained with a lesion with the auditory cortex in rewired animals (shown by the asterisks).(D) Neuronal density of parvalbuminimmunoreactive cells (PVIr) inside layers in the auditory and visual cortices in standard and enucleated hamsters.In V of manage animals, PVIr are primarily identified in layer V and in lesser density in layer IV.Following enucleation, the density of PVIr neurons is now higher in layer IV than the controls.This contrasts with all the reduced density of PVIr neurons in layer V.The resulting pattern of laminar distribution of PVIr cells in the primary visual cortex resembles that on the primary auditory cortex (adapted from Ptito et al a; Ptito and Desgent, Desgent et al).Reactive Blue 4 MedChemExpress Frontiers in Psychology Consciousness ResearchFebruary Volume Post Kupers et al.Blindness and consciousnesscells responding to visual stimuli show orientation selectivity and motion and path sensitivity (Figure B).These receptive field properties compare favorably effectively with those obtained from cells in the visual cortex of standard hamsters (Ptito et al a).In the behavioral level, rewired hamsters can find out visual discrimination tasks also as nor.