Participation of the medial reticular formation of the medulla oblongata in the supraspinal control of locomotor and postural activities in the guinea pig.

The influence of microinjections of novocaine (1.5 microliters of a 2% solution) into the ventromedial areas of the reticular formation of the medulla oblongata on the effects of electrical stimulation of the mesencephalic locomotor region, and of adequate stimulation of the vestibular apparatus, was investigated in experiments on decerebrate guinea pigs. It was demonstrated that such injections are accompanied by a reversible increase in the threshold of stimulation of the region indicated, necessary for the initiation of locomotor rhythmicity, as well as by the suppression of vestibular influences on the activity of the flexor muscles of the extremities. The role of the reticular formation of the brainstem in the supraspinal control of posture and locomotion is discussed.