Mobility performance with a pixelized vision system.
A visual prosthesis, based on electrical stimulation of the visual cortex, has been suggested as a means for partially restoring functional vision in the blind. The prosthesis would create a pixelized visual sense consisting of punctate spots of light (phosphenes). The present study investigated the feasibility of achieving visually-guided mobility with such a visual sense. Psychophysical experiments were conducted on normally sighted human subjects, who were required to walk through a maze which included a series of obstacles, while their visual input was restricted to information from a pixelized vision simulator. Walking speed and number of body contacts with obstacles and walls were measured as a function of pixel number, pixel spacing, object minification, and field of view. The results indicate that a 25 x 25 array of pixels distributed within the foveal visual area could provide useful visually guided mobility in environments not requiring a high degree of pattern recognition.
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Department of Bioengineering, University of Utah, Salt Lake City 84112.
Horch
K W
KW
Normann
R A
RA
D001766:Blindness / Q000534:rehabilitation*; D004558:Electric Stimulation; D006801:Humans; D008124:Locomotion / Q000502:physiology*; D010719:Phosphenes / Q000502:physiology; D019736:Prostheses and Implants; D014785:Vision, Ocular; D014793:Visual Cortex / Q000502:physiology*