[Effect of adequate stimulation of the vestibular apparatus on the locomotor activity of the muscles in the fore- and hindlimbs of the guinea pig. Rotation relative to the lateral axis].

Influence of adequate vestibular stimulation by tilting about a transverse axis on the locomotor activity of fore- and hindlimb muscles was investigated in precollicularly decerebrated guinea pigs. The locomotor activity was evoked by electrical stimulation of the mesencephalic locomotor region. An increase in the forelimb extensors activity and a decrease in the hindlimb extensors activity in the support phase of the locomotor cycle were observed during head downward position, opposite changes of these activities were observed during head upward position. A decrease in the forelimb flexor activity in swing phase during head downward position and an increase in this activity during head upward position was registered. Phase shifts of the locomotor activity changes of forelimb extensors altered from 60 to -30 degrees, hindlimb extensors--from -150 to -220 degrees, forelimb flexors--from -140 to -220 degrees during sinusoidal tilting in frequency range of 0.02-0.4 Hz and amplitude +/- 20 degrees. Mechanisms of observed changes in the locomotor activity of muscles are discussed.