A First: Paralyzed Man Regains Sense of Touch through Brain-Machine Interface
Researchers from the University of Pittsburgh, funded by DARPA, have demonstrated for the first time in a human a technology that allows an individual to experience the sensation of touch directly in the brain through a neural interface system connected to a robotic arm. Nathan Copeland, the volunteer for the study, has lived with quadriplegia from the upper chest down since a 2004 car accident. Nearly ten years after the accident, Nathan underwent surgery to have four microelectrode arrays placed in his brain, two in the motor cortex, and two in the sensory cortex regions that correspond to feeling in his fingers and palm. The researchers ran wires from those arrays to a robotic arm developed by the Applied Physics Laboratory (APL) at Johns Hopkins University. The APL arm contains torque sensors that detect when pressure is being applied to any of its fingers, and can convert those physical 'sensations' into electrical signals that the wires carry back to the arrays in Nathan's brain to provide precise patterns of stimulation to his sensory neurons. In the first set of tests, in which researchers gently touched each of the robotic fingers while Nathan was blindfolded, he was able to report with nearly 100 percent accuracy which finger was being touched.