The most advanced brain-computer interface for operating a robotic arm has given a woman paralyzed from the waist down a new lease on life. Researchers from the University of Pittsburgh implanted two 4mm by 4mm chips into the woman’s motor cortex, the part of the brain responsible for body movements. Each chip is connected to 96 electrodes that are wired through the woman’s skull to a robotic arm. The complexity and number of electrode connections is about twice as many as the researchers have attempted in the past, and the sophistication of the circuitry gives the woman a more “natural and realistic movement of the arm and hand”.
According to MIT Technology Review:
“After the electrodes were implanted into her brain, [the woman] began her training by watching the arm move and imagining that she was controlling it. All the while, the computer was recording neural activity in her motor cortex, and this information was used to better decode her intentions into movements of the robot arm. “Then we started to give her some control,” says Jennifer Collinger, a biomedical engineer at Pittsburgh and the first author on the study. “That generates a feedback loop—she can see whether what she is thinking is moving the arm in the right direction or not. Eventually, we took off those training wheels and gave her full control.”
The woman can now move cubes and other objects around a table and can pick up a two-pound rock. She has also demonstrated the ability to pick up food and feed herself.