REARRANGEMENT OF EFFERENT ACTIVITY OF THE LOCOMOTOR GENERATOR UNDER ELECTRICAL ACTIVATION OF DESCENDING SYSTEMS IN IMMOBILIZED CATS

The effects of signals travelling through vestibulo-, rubro-, reticulo-, and corticospinal systems on the parameters of locomotor generator activity were investigated in decerebrate immobilized cats. Certain phase-linked alterations in these parameters were found to occur under the effects of electrical stimulation applied to these systems (brief trains of stimuli). The biggest increase in locomotor cycle length was produced by electrical stimulation of Deiter's nucleus - stimulus presentation at the end of the extension phase; stimulation at the flexor stage leads to a shortening of this cycle. Maximum increase in locomotor cycle length produced by electrical stimulation of the red nucleus and nucleus gigantocellularis reticularis together with the pyramidal tract takes place during the first half of the flexion phase. Electrical activation of these descending pathways during the flexion phase induces intensification of this phase and reduced intensity of the extension phase. Activation of the vestibulospinal tract produces increased and reduced intensification of the extension phase respectively. Principles of suprasegmental correction of locomotor and scratch generators are compared.