They had been losing their central vision for years, which is what allows them to see letters, faces and details clearly. The light-receptor cells in their eyes had been deteriorating, gradually blurring their vision. But after receiving an experimental eye implant as part of a clinical trial, some of the study participants can now see well enough to read a book, play cards, and complete a crossword puzzle; that, despite being legally blind. Science Corporation, the California brain-computer interface (BCI) company developing the implant, announced preliminary results this week.
When Max Hodak, CEO of the company and former president of Neuralink, first saw the video of a blind patient reading with the implant, he was stunned. This led the company he founded in 2021, after leaving Elon Musk’s corporation, to acquire Pixium Vision’s technology earlier this year. “I don’t think anyone in this field has seen videos like that before,” he says.
What Science Corporation proposes
The implant called Prima consists of a 2 mm square chip that is surgically placed under the retina in an 80-minute procedure. Glasses with a camera capture visual information and emit infrared light patterns on the chip, which has 378 luminous pixels. It acts like a tiny solar panel, converting light into a pattern of electrical stimulation and sending those electrical impulses to the brain. The brain organ interprets these signals as images, imitating the process of natural vision.
In the past, there have been other attempts to restore vision by electrically stimulating the retina. One of them, called Argus II, was approved for commercial use in Europe in 2011 and in the United States in 2013. That implant consisted of larger electrodes that were placed on top of the retina. Its manufacturer, Second Sight, stopped producing the device in 2020 due to financial difficulties. For their part, Neuralink and other companies aim to bypass the eye entirely and stimulate the brain’s visual cortex instead.
These devices manage to produce points of light called ‘phosphenes’ in people’s field of vision, like points on a radar screen. They are enough for people to perceive people and objects as whitish dots, but they are very far from natural vision. Prima is differentiated from other retinal implants by its ability to provide ‘shape vision’, that is, the perception of shapes, patterns and other visual elements of objects. However, what users see is not “normal” vision, since they do not perceive color, rather they see an image processed with a yellowish tint.
Stronger than steel, more effective than any metal. InBrain Neuroelectronics, a Spanish biotechnology company, sees carbon material as a way to power the brain-computer interfaces of the future.
Implant that acts as a ‘photoreceptor’
The trial involved people with geographic atrophy, an advanced form of age-related macular degeneration (AMD) that causes gradual loss of central vision. People with this disease retain peripheral vision, but have blind spots in central vision, making it difficult to read, recognize faces, or see in low light.
In AMD, ‘photoreceptors’, cells at the back of the retina that convert light into signals and then send them to the brain, become damaged over time. “The photoreceptors are lost, but the retina is largely preserved. Our approach is for the implant to take the place of the photoreceptors,” explains Daniel Palanker, inventor of the Prima implant and professor of ophthalmology at Stanford University.
#Neuralink #rival #claims #eye #implant #restored #vision #blind #people
