Paralyzed from the neck down after suffering a gunshot wound when he was 21, Erik G. Sorto now can move a robotic arm just by thinking about it and using his imagination through a clinical trial collaboration between Caltech, Keck Medicine of USC and Rancho Los Amigos National Rehabilitation Center.
Caltech and Keck researchers implanted neuroprosthetics in a part of the brain that controls the intent to move, with the goal of producing more natural and fluid motions. The study, published in Science, was led by Richard Andersen. A quadriplegic implanted with the device was able to perform a fluid handshaking gesture and play “rock, paper, scissors” using a separate robotic arm.
Andersen and colleagues improved the versatility of movement that a neuroprosthetic can offer by recording signals from the PPC brain region. He said: “The PPC is earlier in the pathway (than the motor-cortex, a target of earlier neuroprosthetics,) so signals there are more related to movement planning—what you actually intend to do—rather than the details of the movement execution. We hoped that the signals from the PPC would be easier for the patients to use, ultimately making the movement process more intuitive. Our future studies will investigate ways to combine the detailed motor cortex signals with more cognitive PPC signals to take advantage of each area’s specializations.”