Paralyzed man drinks beer with robotic arm using only thoughts

A team of researchers has come up with a new kind of brain implant that senses a patient's intent to move a robotic arm, offering new promise to paralyzed people.

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 collaboration between Caltech, Keck Medicine of USC and Rancho Los Amigos National Rehabilitation Center, the now 34-year-old Sorto is the first person in the world to have a neural prosthetic device implanted in a region of the brain where intentions are made, giving him the ability to perform a fluid hand-shaking gesture, drink a beverage and play "rock-paper-scissors" using a robotic arm.

Neural prosthetic devices implanted in the brain's movement center, the motor cortex, can allow patients with paralysis to control the movement of a robotic limb. However, current neuroprosthetics produce motion that is delayed and jerky, not the smooth and seemingly automatic gestures associated with natural movement.

Now, by implanting neuroprosthetics in a part of the brain that controls not the movement directly but rather our intent to move, Caltech researchers have developed a way to produce more natural and fluid motions.

Principal investigator Richard Andersen and his colleagues wanted to improve the versatility of movement that a neuroprosthetic can offer to patients by recording signals from a different brain region other than the motor cortex, i.e., the posterior parietal cortex (PPC), a high-level cognitive area.

Sorto, a single father of two who has been paralyzed for over 10 years, said that he was surprised at how easy it was [to control the robotic arm, adding that he remembers just having this out-of-body experience and wanted to just run around and high-five everybody.