Retinotopy within rat primary visual cortex in response to electrical stimulation of the retina

Retinal degenerative disorders are one of the leading causes of human blindness in adult life. Electronic retinal prostheses aim to restore vision in blind people who have photoreceptor cell loss by electrically stimulating the inner retina. We conducted in-vivo experiments, in which we electrically stimulated the retina and measured electrically evoked potentials (EERs) from the visual cortex of rat brains. We mapped the regions of electrophysiology activity in the visual cortex in response to electrical stimulation of the retina. Cortical activity was recorded in the same regions as seen with light stimulus of retina in previously published studies. The strength of the electrically evoked responses in the visual cortex showed a dose-response characteristic with respect to the amount of charge delivered to the retina.