This book dealing with stance and motion was planned in June 1986 at a meeting held in Moscow and Leningrad between a group of Soviet and French scientists interested in motor control. This meeting took place in the framework of an exchange program between the USSR Academy of Seiences and the French Centre National de la Recherche Scientifique. It was very successful event and was greatly appreciated by all those who attended it. Several participants put forward the proposal that the possibility of publishing a book was worth exploring. What were the reasons for publishing a book on stance and motion ? The interest aroused in the participants by each others contributions was not a sufficiently decisive argument. It was feit, however, that a large proportion of the orginal material presented at the meeting, especially in the field of posture and locomotion but also on other aspects covered by the book could be presented in a summarized form which should appeal to a larger audience because the facts and hypotheses they contained especially those from the Soviet participants, were not very familiar among international circles, and that many scientists would appreciate having a single volume containing a survey ofthe current state of research in this field. This was also the opinion of Plenum Press, who agreed to publish the book. Each participant at the meeting submitted a paper which was examined by two referees before being accepted.

This book dealing with stance and motion was planned in June 1986 at a meeting held in Moscow and Leningrad between a group of Soviet and French scientists interested in motor control. This meeting took place in the framework of an exchange program between the USSR Academy of Seiences and the French Centre National de la Recherche Scientifique. It was very successful event and was greatly appreciated by all those who attended it. Several participants put forward the proposal that the possibility of publishing a book was worth exploring. What were the reasons for publishing a book on stance and motion ? The interest aroused in the participants by each others contributions was not a sufficiently decisive argument. It was feit, however, that a large proportion of the orginal material presented at the meeting, especially in the field of posture and locomotion but also on other aspects covered by the book could be presented in a summarized form which should appeal to a larger audience because the facts and hypotheses they contained especially those from the Soviet participants, were not very familiar among international circles, and that many scientists would appreciate having a single volume containing a survey ofthe current state of research in this field. This was also the opinion of Plenum Press, who agreed to publish the book. Each participant at the meeting submitted a paper which was examined by two referees before being accepted.

This volume covers the proceedings of a symposium held in Marseille in March 1982 as a satellite meeting of the IBRO First World Congress in Lausanne. About 70 participants from more than ten countries attended the symposium, whose central theme was "Neural Coding of Motor Performance. " Whereas coding within the sensory systems has been dis cussed widely, coding in the field of motor control has been analyzed much less. Over the past 10 years an impressive amount of information has been assembled combining re- . cordings in central and peripheral neural structures during the performance of simple and complex motor tasks. Data such as those relating the behavioral phenomena of the awake animal to single-cell recordings from various cerebral areas have been carefully worked out by a number of investigators. It was thought at the symposium that the time had come for this infor mation to be collected and reexamined, and presented in one volume. The present book was conceived to cover the scope and significance of coding throughout the nervous system. by "coding" in the central nervous system? This What is meant question can be answered in general by bringing together data and viewpoints from many disciplines - behavior, neurophysi ology, neuropharmacology - and clinical observations. Gen erally speaking, one may call coding a method of communica tion, i. e., the language that brain cells use for exchange of information."