Progress Continues On Pursuit of Mind-Controlled Prosthetics


Researchers working out of an Icelandic orthopedics company called Ossur announce that they recently tested a mind-controlled prosthetic leg on two amputees with promising results from both experiments. The devices are lower-limb prosthetics and communicate with the remaining muscle tissue through a mesh network of sensors implanted in the residual muscle tissue. As a result, signals sent from the brain to the leg are able to continue on through the leg and into the prosthetic. This allows the prosthetic to respond to subconscious instructions that brought a needed sense of cohesion between the device and the wearer. Gummi Olafsson, one of the recipients of the new device, describes the initial sensation of using it:

It was, like you couldn’t believe the feeling when you were moving your ankle. It was really strange. I couldn’t explain it. It was like, I was moving it with my muscles, there was nobody else doing it, the foot was not doing it, I was doing it, so it was really strange and overwhelming.

The results of the experiment were unveiled last week by CEO Jon Sigurdsson, who confirmed that the two patients are the first in the world to have prosthetics capable of being controlled through subconscious muscle memory patterns.

Meanwhile, at CalTech, another team of researchers has made equally impressive gains on work they are doing with small chips designed to be implanted directly into the brain. The team tested their “neuroprosthetic” design on a tetrapalegic man named Eric Sorto that lost control of nearly all his mobility 10-years ago due to a gunshot wound. The man was clear going into the experiment that after years of having caregivers placing straws in his mouth for him, his first goal was to grasp and then drink a beer by himself.

To make this goal a reality, surgeons implanted a chip in the posterior parietal cortex, the part of the brain where the intention to move is born. The posterior parietal cortex sends a signal to the motor cortex, which is responsible for controlling movement at a more detailed level. By working from this higher level, the team has improved on earlier mind-controlled devices and simplified the user experience. Before, scientists interfaced directly with the motor cortex, and while this worked, it required users to imagine every step required to accomplish a task, from moving an arm toward a can, to adjusting the wrist in just hte right way, to closing the fingers around the can in a grasp. However, with this new system, users intentions are captured and interpreted externally, simplifying the entire process.

In this study, intentions captured by the chip were relayed to an external computer where the role of the motor cortex was replaced by software. Here, detailed instructions on how to accomplish the movement intentions being relayed by the brain are created and then passed to a detached robotic arm. For fully paralyzed patients like Sorto, brain-controlled robotic aids hold great promise in returning aspects of normalcy to their lives. Lead CalTech researcher and author of the study Richard Anderson, reports that Sorto has accomplished both his personal goal as well as many other tasks, "He’s been able to do various things. He can play video games and do rock paper scissors, he can grasp objects. And of course he had a personal goal, which is to control the speed at which he drinks a beer, so we implemented that first." The findings of this study were published in Science.

Enjoy HIStalk Connect? Sign up for update alerts, or follow us at @HIStalkConnect.

↑ Back to top

Founding Sponsors

Platinum Sponsors