Evaluation of extraocular electrodes for a retinal prosthesis using evoked potentials in cat visual cortex

A cortical (V1) neurophysiological recording model for assessing the efficacy of retinal visual prostheses

“…Some investigators have used animal models to examine how electrical stimulation of the retina affects the responses of ganglion cells (Grumet et al, 2000;Stett et al, 2000;Jensen et al, 2003Jensen et al, , 2005a. Other groups have used animal models to examine how electrical stimulation of the retina affects the cortical response, either at a very gross scale, obtained by skull recordings of evoked potentials Schanze et al, 2005;Yamauchi et al, 2005;Chowdhury et al, 2005), at an intermediate scale, obtained by local-field potential recordings (Wilms et al, 2003) and by optical imaging of the cortex (Walter et al, 2005), and finally, at a cellular level, obtained by recording multi-unit spiking activity (Eger et al, 2005).…”

Development of an extraocular retinal prosthesis: Evaluation of stimulation parameters in the cat

“…Recently, an extraocular approach to developing a retinal prosthesis has been proposed. 21,22 An extraocular retinal prosthesis (ERP) incorporates electrodes that are placed on the outer scleral surface of the eye (Fig. 1).…”

Spatiotemporal Properties of Multipeaked Electrically Evoked Potentials Elicited by Penetrative Optic Nerve Stimulation in Rabbits

“…6 -12 These retinal devices have been developed for epiretinal and subretinal locations. Visual prostheses based on suprachoroid, 13,14 intrapapilla, 15,16 extraocular, 17,18 and thalamic 19 electrical stimulation have also been proposed. Preliminary clinical trials by several groups 8 -11,20 have reported some degree of success.…”