Dynamic Stimulation of Visual Cortex Produces Form Vision in Sighted and Blind Humans
Michael S Beauchamp, Denise Oswalt, Ping Sun, Brett L Foster, John F Magnotti, Soroush Niketeghad, Nader Pouratian, William H Bosking, Daniel Yoshor, Michael S Beauchamp, Denise Oswalt, Ping Sun, Brett L Foster, John F Magnotti, Soroush Niketeghad, Nader Pouratian, William H Bosking, Daniel Yoshor
Abstract
A visual cortical prosthesis (VCP) has long been proposed as a strategy for restoring useful vision to the blind, under the assumption that visual percepts of small spots of light produced with electrical stimulation of visual cortex (phosphenes) will combine into coherent percepts of visual forms, like pixels on a video screen. We tested an alternative strategy in which shapes were traced on the surface of visual cortex by stimulating electrodes in dynamic sequence. In both sighted and blind participants, dynamic stimulation enabled accurate recognition of letter shapes predicted by the brain's spatial map of the visual world. Forms were presented and recognized rapidly by blind participants, up to 86 forms per minute. These findings demonstrate that a brain prosthetic can produce coherent percepts of visual forms.
Trial registration: ClinicalTrials.gov NCT03344848.
Keywords: blind; brain; dynamic; electrical; electrodes; human; phosphene; prosthetic; stimulation; visual.
Conflict of interest statement
Declaration of interests W.H.B., N.P., and D.Y. receive research funding from Second Sight Medical Products, a manufacturer of visual cortical prosthetics. N.P. is also a consultant to Second Sight. A provisional patent application describing dynamic current steering (serial no. 62/638,365) was filed with the US Patent and Trademark Office on March 5, 2018, entitled “Systems and Computer-Implemented Methods of Conveying a Visual Image to a Blind Subject Fitted with a Visual Prosthesis.”
Published by Elsevier Inc.
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Source: PubMed