One day, it will be possible to replace nerves with entirely artificial conduits. This is a branch of medical technology that will compete with regenerative medicine, and ultimately lead to more effective and resilient body parts. But today, the foundations are still being designed. A long road lies ahead. Here, the New Scientist looks at early work: "Schiefer is describing an experiment in which pulses of electricity are used to control the muscles of an unconscious patient, as if they were a marionette. It represents the beginnings of a new generation of devices that he hopes will allow people with paralysed legs to regain control of their muscles and so be able to stand, or even walk again. His is one of a raft of gadgets being developed that plug into the network of nerves that normally relay commands from the spinal cord to the muscles, but fall silent when a spinal injury breaks the chain. New ways to connect wires to nerves [allow] artificial messages to be injected to selectively control muscles just as if the signal had originated in the brain. Limbs that might otherwise never again be controlled by their owners can be brought back to life. ... Nerves contain tens of thousands of axons, each capable of being controlled by the ultimate puppeteer: the brain. Learning to pull even a few of those strings, though, could restore partial function to a person's limb, restoring some control to an arm or leg that was previously paralysed."