What kind of signal does a human retina produce? To try to answer this question, Fernandez takes human retinas from people who have recently died, hooks the retinas up to electrodes, exposes them to light, and measures what hits the electrodes. Fernandez and his team first had to figure out the camera part. If the basic idea behind Gómez’s sight-plug a camera into a video cable into the brain-is simple, the details are not. In the early 2000s, the hypothetical became a reality when an eccentric biomedical researcher named William Dobelle installed such a prosthesis in the head of an experimental patient. Some researchers even built rudimentary systems. Scientists and sci-fi authors have since imagined the potential for a camera-to-computer-to-brain visual prosthesis. In 1929, a German neurologist named Otfrid Foerster discovered that he could elicit a white dot in the vision of a patient if he stuck an electrode into the visual cortex of the brain while doing surgery. The long history of experiments leading to her successful implant has a checkered past. The implant surgery was so uneventful, she says, that she came to the lab the very next day to get plugged in and start the experiments. Today there’s virtually no evidence of the port. At one point during this meeting, as Fernandez explains how the hardware connects to the skull, Gómez interrupts the discussion, tilts forward, and places the prospect’s hand on the back of her head, where a metal outlet used to be. She’s also here to meet a potential second patient who is in town, and in the room during my visit. Gómez is here for a brain MRI to see how things look half a year after having her implant removed (they look good). When I reach out to shake her hand, her husband guides her hand into mine. When I walk over to greet her, Gómez’s face is initially pointing in the wrong direction until I say hi. When I finally see her in the lab, I notice Gómez knows the layout of the space so well she barely needs help navigating the small hallway and its attached rooms. (Second Sight says slightly more than 350 people are using its Argus II retinal implant.) That’s why in 2015, the company Second Sight, which received approval to sell an artificial retina in Europe in 2011-and in the US in 2013-for a rare disease called retinitis pigmentosa, switched two decades of work away from the retina to the cortex. An artificial eye won’t solve their blindness.
It worked, but the vast majority of blind people, like Gómez, have damage to the nerve system connecting the retina to the back of the brain. Much earlier research attempted to restore vision by creating an artificial eye or retina. Fernandez’s approach is particularly exciting because it bypasses the eye and optical nerves. His goal: to return sight to as many as possible of the 36 million blind people worldwide who wish to see again. Gómez’s first moment of sight, at the end of 2018, was the culmination of decades of research by Eduardo Fernandez, director of neuroengineering at the University of Miguel Hernandez, in Elche, Spain.
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