Periodic fluctuation in burst amplitude during 'fictive locomotion' in the cat

In decorticated unanaesthetized and paralysed cats, locomotor bursting may develop spontaneously on hind-limb motor nerves. In defined experimental conditions, the amplitude of successive rhythmic bursts may fluctuate periodically as if a 'secondary oscillation' was superimposed upon the basic locomotor rhythm. The possible meaning of such amplitude fluctuation is discussed in connection with present data about the generation of locomotion.