Figure 5.16: Artificial limb controlled by rewired nerves Claudia Mitchell lost her left arm In a motorcycle accident. Bravely, she agreed to be a test case for a pioneering new kind of surgery. Surgeons reconnected the nerves that used to go to her arm and hand to muscles in her chest. After that she could make different muscles in her chest twitch by thinking about moving her missing arm or fingers. The next step was to use the signals from those muscle twitches, amplified and analyzed by a tiny computer, to operate her new artificial arm and fingers. The result is that she can move the artificial arm and fingers in a wide variety of useful ways, just by thinking about doing so. For example, if she wills herself to reach out and grasp an object with her left hand, the artificial limb obeys her will, just as her biological limb did before it was lost (Kiuken et al., 2007).

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