Erik Sorto lost his ability to move his arms and legs after suffering a gunshot wound 13 years ago.
While the injury has left him quadriplegic, he has now been given a chance to do some basic actions courtesy of a robotic arm controlled through his brain.
The robotics project was made possible through the combined efforts of researchers from the California Institute of Technology (Caltech) and the University of Southern California (USC).
In 2013, doctors from USC implanted a pair of microchips into Sorto's brain designed to decode his thoughts to move the robotic arm. These sensors are responsible for recording the electrical activity of his brain cells whenever he thinks about reaching or grasping an object.
Scientists and therapists from Caltech worked with Sorto for several weeks to help fine-tune the movements of the robotic arm.
Richard Andersen, professor of neuroscience at Caltech and principal author of the study, said they asked Sorto to think about what he wanted to do using the arm instead of giving him a series of steps on how to do it.
The sensors in Sorto's brain were able to bypass the damage in his spinal cord, allowing him to conduct basic movements using the robotic arm, beginning with a simple handshake until he was able to do more complicated actions.
"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," Sorto said. "I really miss that independence."
When he first tried out using the robotic arm to pick up a bottle of beer, he was so excited that he lost concentration and spilled the beer. On his second attempt, Sorto was able to guide the arm to bring the beer close to him, and he sipped it using a straw.
According to the study, the researchers focused on a part of the brain called the posterior parietal cortex in order to make the robotic arm move. This is the region mostly responsible for planning the movements of the body.
Previous research on robotics targeted the motor cortex of the brain, which is believed to be in charge of movement.
Andersen explained that they wanted "to extract the intent of the subject" by studying the signals given out by the posterior parietal cortex. He said smart robotics can be used to understand the fine details of the study instead of focusing on controlling the muscles.
The researchers hope that they can make the movements of the robotic arm smoother using this strategy.
The differences between the two approaches have yet to be determined as no side-by-side comparison has been conducted so far. The latest study, however, provides scientists with another region of the brain to target in their research.
The findings of the study are published in the journal Science.
