A new new kind of thought-controlled artificial arm that moves more easily than other devices has been developed by Johns Hopkins University researchers.

The technique, called targeted muscle reinnervation, involves taking the nerves that remain after an arm is amputated and connecting them to another muscle in the body, often in the chest. Electrodes are placed over the chest muscles, acting as antennas. When the person wants to move the arm, the brain sends signals that first contract the chest muscles, which send an electrical signal to the prosthetic arm, instructing it to move.