Chapter 31 Locomotor Performance and Adaptation after Partial or Complete Spinal Cord Lesions in the Cat

Abstract

Publisher Summary Much of the information on the role of various structures of the central nervous system (CNS) in the regulation of different aspects of locomotion in the cat comes from the studies based on microstimulation, unit recordings, or acute ablations. Less attention has been paid to the performance and functional reorganization of locomotor control after chronic lesions of these central structures. In part, this may be because interpretation of the results of such studies is problematic in that it has to take into consideration the fact that the consequences of the lesion on the expression of the remaining functions are a mixture of deficits due to the removed structures and due to compensation by other structures. Nevertheless, some indication of the degree of compensation can be obtained by comparing the short- and long-term locomotor performance. In the short term, the deficits represent the uncompensated state and give some indication of the normal role of a given structure in the control of locomotion. Later, after the maximal compensation has taken place, the remaining permanent behavioral deficits give a fair indication of the essential contributions of the ablated structures and the limits of other structures to replace, totally or in part, the function of the missing structures. This chapter summarizes the results of the different studies in which the locomotor performance of chronically instrumented cats was documented before and after either partial or complete spinal lesions. It discusses some of the kinematic and electromyographic (EMG) changes that occur during ordinary treadmill locomotion and briefly describes how these lesioned cats adapt their locomotion to more demanding situations (slopes, tilts, and obstacles). Finally, it correlates these changes with the current knowledge on the function of different supra-spinal structures in the control of locomotion obtained from unit recording and microstimulation studies.