A paralyzed man has been able to feed himself by using his thoughts to send messages from implants in his brain to receptors in his arm. Bill Kochevar, who was paralyzed in a cycling accident eight years ago, said he was "wowed" to regain control of his right arm. Researchers say this is the first time anyone has been able to restore brain-controlled reaching and grasping in a person with complete paralysis. But the technology is a long way from being used outside the lab.
For the study, Kochevar had surgery to place sensors in the motor cortex area of his brain, the area responsible for hand movement. He then spent four months using the sensors to command movements of a three-dimensional virtual arm. After this, he had 36 electrodes implanted in his arm and hand to electrically stimulate his hand, elbow and shoulder muscles.
The researchers used a decoder to translate his brain signals into commands for the electrodes in his arm. He was then able to intuitively command his arm to move. "I was making it move without having to really concentrate hard at it. I just think 'out' and it just goes," he said.
Previous research has seen a system with electrodes on the skin help people move their hands. Other studies have also seen participants controlling robotic arms using their brain signals. But researchers believe this study represents a major advance with potential for future uses outside the lab.
"Although similar systems have been used before, none of them has been as easy to adopt for day-to-day use and they have not been able to restore both reaching and grasping actions," said lead author behind the study at Case Western Reserve University in Cleveland, Ohio. He acknowledged that the research was at an early stage but "we believe that this neuro-prosthesis could offer individuals with paralysis the possibility of regaining arm and hand functions to perform day-to-day activities, offering them greater independence.