Before revision: Sandro Mussa-Ivaldi, Mitsuo Kawato, Claude Ghez, Reza Shadmehr and Konrad Kording contributed with numerous behavioral experiments.
After revision: , Randy FlanaganSandro Mussa-Ivaldi, Mitsuo Kawato, Claude Ghez, Reza Shadmehr and Konrad Kording contributed with numerous behavioral experiments.