Elon Musk recently made a statement on X regarding the Blindsight, a cortical implant designed to restore vision. Musk mentioned that the initial resolution of the implant may be low, but it could potentially exceed normal human vision in the future.
However, a recent research study from the University of Washington suggests that Musk’s projection for the Neuralink project may be unrealistic. Ione Fine, the lead author of the study and a professor of psychology at UW, stated that Musk’s premise of achieving high-resolution vision by implanting millions of tiny electrodes into the visual cortex is flawed. The visual cortex is responsible for processing information received from the eye.
In a study, researchers developed a computational model to simulate a broad range of human cortical studies, including the experience of high-resolution implants such as Blindsight. One simulation revealed that while a movie of a cat at a resolution of 45,000 pixels appears crystal-clear, a movie simulating the experience of a patient with 45,000 electrodes implanted in the visual cortex would perceive the cat as blurry and barely recognizable.
This is because, according to Fine, a single electrode does not represent a pixel, but rather stimulates at most a single neuron.
Unlike the tiny ‘dots’ of pixels on a computer screen, the visual cortex operates differently. Each neuron informs the brain about images within a small region of space known as the “receptive field,” with these fields overlapping. Consequently, a single spot of light stimulates a complex pool of neurons. The sharpness of an image is not determined by the size or number of individual electrodes but rather by the way information is represented by thousands of neurons in the brain.
“Engineers often think of electrodes as producing pixels,” Fine said, “but that is simply not how biology works. We hope that our simulations based on a simple model of the visual system can give insight into how these implants are going to perform. These simulations are very different from the intuition an engineer might have if they are thinking in terms of pixels on a computer screen.”
New research from the University of Washington created a computational model that simulated a wide range of human cortical studies. The image on the left was generated using 45,000 pixels. The one on the right — representative of high-resolution cortical implants like Elon Musk’s Blindsight — uses 45,000 electrodes. Credit: Ione Fine
The researchers used a combination of animal and human data to create computational “virtual patients” that demonstrate how electrical stimulation in the visual cortex could potentially improve vision. While even blurry vision would be a significant breakthrough, caution is advised as these simulations represent the best-case scenario for visual implants.
Although Musk is making progress in the engineering aspect of visual implants, a major challenge remains – recreating a neural code that produces clear vision once the electrodes are implanted and stimulates single cells.
“Even to get to typical human vision, you would not only have to align an electrode to each cell in the visual cortex, but you’d also have to stimulate it with the appropriate code,” Fine said. “That is incredibly complicated because each individual cell has its own code. You can’t stimulate 44,000 cells in a blind person and say, ‘Draw what you see when I stimulate this cell.’ It would literally take years to map out every single cell.”
At present, Fine asserts that the search for the correct neural code in blind individuals remains an unsolved challenge for scientists.
“Somebody might one day have a conceptual breakthrough that gives us that Rosetta Stone,” Fine said. “It’s also possible that there can be some plasticity where people can learn to make better use of an incorrect code. But my own research and that of others shows that there’s currently no evidence that people have massive abilities to adapt to an incorrect code.”
Without this crucial advancement, the visual output from projects like Blindsight will continue to be blurry and imperfect, regardless of the advancement in electronic technology.
The study’s models can presently assist researchers and companies in optimizing the placement of existing devices and innovating new technologies, offering a range of benefits. Additionally, regulatory bodies such as the Food and Drug Administration and Medicare will gain valuable insights into the crucial tests needed for device evaluations. Furthermore, the models can provide realistic expectations for surgeons, patients, and their families.
“Many people become blind late in life,” Fine said. “When you’re 70 years old, learning the new skills required to thrive as a blind individual is very difficult. There are high rates of depression. There can be desperation to regain sight. Blindness doesn’t make people vulnerable, but becoming blind late in life can make some people vulnerable. So, when Elon Musk says things like, ‘This is going to be better than human vision,’ that is a dangerous thing to say.“
Journal reference:
Ione Fine & Geoffrey M. Boynton. A virtual patient simulation modeling the neural and perceptual effects of human visual cortical stimulation, from pulse trains to percepts. Scientific Reports, 2024; DOI: 10.1038/s41598-024-65337-1
>>> Read full article>>>
Copyright for syndicated content belongs to the linked Source : Tech Explorist – https://www.techexplorist.com/cortical-implants-unlikely-exceed-normal-human-vision/86650/#utm_source=rss&utm_medium=rss&utm_campaign=cortical-implants-unlikely-exceed-normal-human-vision
