[Effect of adequate stimulation of the vestibular apparatus on the locomotor activity of the forelimb muscles in the guinea pig. Rotations relative to the longitudinal axis]

Abstract

Influence of the adequate vestibular stimulation by tilting about the longitudinal axis on the locomotor activity of forelimb muscles was investigated in precollicularly decerebrated guinea pigs. The locomotor activity was evoked by electrical stimulation of the mesencephalic locomotor region. An increase of the extensor activity in the stance phase and a decrease of the flexor activity in the swing phase on the limb ipsilateral to the tilt and opposite changes of the antagonist muscles activity on the limb contralateral to the tilt were observed during animal movements. It is found that during the sinusoidal tilting in the frequency range of 0.02-0.4 Hz changes in the locomotor activity lead the animal displacement: 60-40--in extensors, 40-20 degrees--in flexors. Mechanisms of the vestibular control of the locomotor activity are discussed.