A California man who has been paralyzed from the neck down for years is now able to drink by himself after receiving neural implants.
Erik Sorto agreed to have a chip implanted in his brain which lets him control a robotic arm using just his mind. Sorto was shot when he was just 21, and has been paralyzed for over a decade. He agreed to take part in a clinical trial involving sensors implanted into the posterior parietal cortex, writes Sophie Curtis for The Telegraph.
Patient regains a measure of independence thanks to implant
The posterior parietal cortex is the region of the brain where we form our intent to make a movement. The sensors detect bursts of electrical signals in the brain and transmit them to a computer, which then sends an instruction to the robotic limb.
After years of paralysis, Sorto learned to control the robotic limb on the first day that it was installed. Researchers from the California Institute of Technology (Caltech) report that Sorto was first able to shake hands with another person, and later learned to take a drink by himself as well as controlling a computer cursor.
“I joke around with the guys that I want to be able to drink my own beer – to be able to take a drink at my own pace, when I want to take a sip out of my beer and to not have to ask somebody to give it to me,” he said. “I really miss that independence. I think that if it was safe enough, I would really enjoy grooming myself – shaving, brushing my own teeth. That would be fantastic,” continued Sorto.
Brain activity was also used to control a robotic hand given to an Italian man who lost half of his arm in a car crash in 2009. However this latest research marks the first time that the sensors have been put in the posterior parietal cortex and not the motor cortex, which is responsible for moving individual muscles.
Implant in new brain region allows more natural movements
Researchers claim that by implanting the sensors in the posterior parietal cortex, they enable more natural and fluid movements.
“When you move your arm, you really don’t think about which muscles to activate and the details of the movement—such as lift the arm, extend the arm, grasp the cup, close the hand around the cup, and so on. Instead, you think about the goal of the movement. For example, ‘I want to pick up that cup of water,'” said principal investigator Richard Andersen.
“So in this trial, we were successfully able to decode these actual intents, by asking the subject to simply imagine the movement as a whole, rather than breaking it down into myriad components,” he continued.
Research ongoing
Laboratories at a number of universities including Brown, Duke and Caltech have been working on brain-controlled prosthetics for years. Other areas of study include wireless implants which can send basic mental commands, robotic leg braces that are controlled by the brain and sensors which let users of robotic hands gain a sense of touch.
Back in 2012 researchers at the University of Pittsburgh unveiled a brain implant which enabled a paralyzed woman to eat a chocolate bar by herself using a robotic arm.
It is certainly encouraging to see machines being used to improve the quality of life of injured humans by linking them with the brain. However the number of successful combinations is still quite small, and experts believe that clinical applications may only become viable in a decade or so.
