The motor system in neuroscience: a history and analysis of conceptual developments.

Neuroscientific reflection on the integrative action of the nervous system was dominated by consideration of the motor system from the time of Aristotle in the 4th century B.C. to that of Sherrington, his contemporaries and proteges in the first-half of the 20th century. We describe the significant discoveries concerning the action of the spinal cord and cortex in motor phenomena during this period. This provides a vivid account of how great neuroscientists, over a period of more than 2000 years, have endeavoured to clarify notions concerning the integrative action of the nervous system in the context of the prevailing philosophical traditions of their times. We examine these traditions as well as the conceptual schemes offered by neuroscientists, especially in relation to the workings of the cortex. It is shown that neuroscientists cleave to this day to a tradition that goes back to Descartes, and that this is the case even for those who explicitly claim to reject such a tradition. The review concludes with what we take to be an appropriate basis for rejecting the Cartesian paradigm that we hope will assist neuroscientists in understanding the integrative action of the nervous system. Copyright 2002 Elsevier Science Ltd.