The origin of voluntary action: history of a physiological concept

The notion that actions are internally represented prior to be executed, and that specific brain areas are devoted to the elaboration of these representations is a challenge for neurophysiology. Questions bearing on the nature of motor centres, on their independence with respect to external stimuli, and on the possibility to monitor or even to perceive their activity are still a matter of debate. Here, we describe a thirty-year exemplary period extending between 1870 and 1900, where critical experiments and clinical observations have contributed to resolve these issues.