Visual resolution with retinal implants estimated from recordings in cat visual cortex.

Reinhard Eckhorn; Marcus Wilms; Thomas Schanze; Marcus Eger; Lutz Hesse; Ulf T Eysel; Zoltán F Kisvárday; Eberhart Zrenner; Florian Gekeler; Helmut Schwahn; Keisuke Shinoda; Helmut Sachs; Peter Walter

doi:10.1016/j.visres.2006.01.034

PubMed · 16571357

Visual resolution with retinal implants estimated from recordings in cat visual cortex.

Reinhard Eckhorn·Marcus Wilms·Thomas Schanze·Marcus Eger·Lutz Hesse·Ulf T Eysel·Zoltán F Kisvárday·Eberhart Zrenner·Florian Gekeler·Helmut Schwahn·Keisuke Shinoda·Helmut Sachs·Peter Walter

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Abstract

We investigated cortical responses to electrical stimulation of the retina using epi- and sub-retinal electrodes of 20-100 microm diameter. Temporal and spatial resolutions were assessed by recordings from the visual cortex with arrays of microelectrodes and optical imaging. The estimated resolutions were approximately 40 ms and approximately 1 degrees of visual angle. This temporal resolution of 25 frames per second and spatial resolution of about 0.8 cm at about 1m and correspondingly 8 cm at 10 m distance seems sufficient for useful object recognition and visuo-motor behavior in many in- and out-door situations of daily life.

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Action Potentials Animals Cats Electric Stimulation Therapy Electrodes, Implanted Microelectrodes Phosphenes Prostheses and Implants Retina Visual Cortex Visual Pathways Visual Perception Journal Article Research Support, Non-U.S. Gov't

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Reinhard Eckhorn, Marcus Wilms, Thomas Schanze, Marcus Eger, Lutz Hesse, Ulf T Eysel, Zoltán F Kisvárday, Eberhart Zrenner, Florian Gekeler, Helmut Schwahn, Keisuke Shinoda, Helmut Sachs, Peter Walter. 2006-03-29. Visual resolution with retinal implants estimated from recordings in cat visual cortex.. https://doi.org/10.1016/j.visres.2006.01.034

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