‘Neurograins’ Become Next Brain-Computer Interfaces
For people with brain and spinal cord injuries, these systems eventually restore communication and mobility, allowing them to live more independently. But now, they are not all are practical. Most require clunky set-ups and cannot be used outside of a research lab. People who wear brain implants are also limited in the variety they can make because of the small neurons that can be recorded on the implants from a single moment. The most commonly used brain chip, the Utah array, is a bed of 100 silicon needles, each with an electrode at the tip that attaches to brain tissue. One of these arrays is about the size of Abraham Lincoln’s face in a US denarius and can record activity from several hundred surrounding neurons.
But many of the brain functions that interest researchers – such as memory, speech, and decision -making – have networks of neurons widely distributed throughout the brain. “To know how these functions work, you have to study them at the system level,” said Chantel Prat, an associate professor of psychology at the University of Washington who is not involved in the project. neurograins. His work involves non-destructive brain-computer interfaces worn on the head rather than inserted.
The ability to record from multiple neurons could enable more fine motor control and extend what is possible with brain -controlled devices. It can also be used by animal researchers to find out how different regions of the brain communicate with each other. “When it comes to how brains work, the totality is more important than the sum of the parts,” he says.
Florian Solzbacher, co-founder and president of Blackrock Neurotech, the company that makes the Utah array, says a distributed neural implant system may not be necessary for many quick applications, such as operating motor trunks. function or use of the computer. However, more futuristic applications, such as memory restoration or thinking, almost certainly require more complex set up. “Obviously, the Holy Grail could be a technology that can record from as many neurons as possible throughout the brain, at the top and at depth,” he said. “Do you need that in all its complexity now? Apparently not. But in terms of understanding the brain and looking at future applications, the more information we have, the better. ”
Small sensors can also mean less brain damage, he continues. Current arrays, even if small, can cause swelling and scarring around the area being inserted. “Usually, if you do a little bit, it’s less likely to be perceived by the immune system as a foreign thing,” said Solzbacher, who was not involved in Brown’s study. If the body finds a foreign object such as a splinter, it tries to digest and destroy it, or encapsulate it in scar tissue.
Even if it’s a little more, it doesn’t have to be crazy, Solzbacher cautions. Although miniscule implants can trigger a resistance response, so neurograins must also be made of biocompatible materials. A major barrier to developing brain implants is trying to minimize damage while constructing a durable implant, to avoid the risk of replacement surgeries. The current arrays last about six years, but many stop working much earlier because of scar tissue.
If neurograins are the answer, there is still the question of how the brain gets them. In their rodent experiment, Brown’s researchers removed many parts of the rat’s skull, which, for obvious reasons, is not good for humans. The current fixed array requires drilling a hole in the patient’s head, but Brown’s team wants to avoid invasive brain surgery. To do this, they devised a method to insert neurograins with associated thin needles into the skull with a special device. (Neuralink chasing a similar “sewing” robot for delivering coin -shaped brain implant.)