This could be the most touchy-feely robotic limb yet. For the first time, brain stimulation has made it possible for a paralysed person to experience the sensation of touch via a bionic hand. Robert Gaunt at the Center for the Neural Basis of Cognition in Pittsburgh, Pennsylvania, and his team achieved this by implanting electrodes in the brain of Nathan Copeland, a 28-year-old quadriplegic. These were inserted into the region of the brain that registers…