WHY THIS MATTERS IN BRIEF
As our knowledge of the human brain improves in the future we might not need eyes to see, as well as having new ways to “cure” blindness.
Historically if you were blind you were blind forever, but technology is changing that paradigm with the development of new 3D printed corneas, bionic eyes, and gene editing tools that reverse blindness, as well as the development of Virtual Reality (VR) technologies that are helping even the legally blind see again.
In a new twist in the race to “cure” blindness though now a team of researchers in Spain have decided to skip the eye entirely and instead just send signals direct to the brain’s visual cortex instead – and so far their trials of this sci-fi like technology have been successful.
Amazingly, 15 years after losing her sight, Bernardeta Gómez, who suffers from toxic optic neuropathy, used the experimental technology to recognize lights, letters, shapes, people, and even to play a basic video game sent directly to her brain via an implant.
See how it works. Courtesy: CNET
According to MIT Technology Review, Gómez first began working with researchers in late 2018. Over the next six months, she spent four days a week dialling in the technology’s settings and testing its limits.
The system, developed by Eduardo Fernandez, director of neuroengineering at the University of Miguel Hernandez, works like this.
A camera embedded in a pair of thick, black-rimmed glasses records Gómez’s field of view and sends it to a computer. The computer translates the data into electrical impulses the brain can read and forwards it to an invasive brain implant by way of a cable plugged into a port in the skull. The implant stimulates neurons in Gómez’s visual cortex, which her brain interprets as incoming sensory information. Gómez perceives a low-resolution depiction of her surroundings in the form of yellow dots and shapes called phosphenes which she’s learned to interpret as objects in the world around her.
The technology itself is still very much in the early stages and Gómez is the first to test it, but the team aims to work with five more patients in the next few years. Eventually, Fernandez hopes their efforts can help return sight to many more of the world’s blind people.
Brain implants are far riskier than eye implants so it could be several years before we see the technology being commercialised, but nonetheless Brain Machine Interfaces (BMIs) are quickly advancing on a number of fronts.
The implant used in Fernandez’s research is a fairly common device called a Utah array. The square array is a few millimeters wide and contains 100 electrode spikes which are inserted into the brain. Each spike stimulates a few neurons. Similar implants have helped paralyzed folks control robotic arms and regain their sense of touch, and type messages with just their thoughts.
Though they’ve been the source of several BMI breakthroughs, the arrays aren’t perfect.
The electrodes damage surrounding brain tissue, scarring renders them useless all too quickly, and they only interact with a handful of neurons. So, as a result the ideal device would have bio-compatible materials and transistors, be wireless, last decades in the brain, limiting the number of surgeries needed, and offer greater precision and resolution.
Ferndandez believes his implant can be modified to last decades, and while the current maximum resolution is 10 by 10 pixels, he envisions one day implanting as many as 6 on each side of the brain to deliver a resolution of at least 60 by 60 pixels.
In addition to all of this work new technologies are in the works. Famously, Elon Musk’s company Neuralink is developing soft, thread-like electrodes that are deftly laced into brain tissue by an autonomous robot. Neuralink is aiming to include 3,000 electrodes on their device to chat up far more neurons than is currently possible, although it’s not clear whether there’s a limit to how many more neurons actually add value. Still other approaches, that are likely further out, such as Facebook’s non-invasive BMI technology, do away with electrodes altogether, using light or chemicals to control gene-edited neurons.
Fernandez’s process also relies on more than just the hardware. The team used machine learning, for example, to write the software that translates visual information into neural code. This can be further refined, and in the coming years, as they work on the system as a whole, the components will no doubt improve in parallel. But how quickly it all comes together in a product for wider use isn’t clear.
Fernandez is quick to dial back expectations, pointing out that these are still early experiments, and he doesn’t want to get anyone’s hopes up. Still, given the choice, Gómez said she’d have elected to keep the implant and wouldn’t think twice about installing version two.
“This is an exciting time in neuroscience and neurotechnology, and I feel that within my lifetime we can restore functional sight to the blind,” says Yoshor.