Vestibulospinal influences in early human postnatal development.

Abstract

Monosynaptic testing (H-reflex) was used to study vestibulospinal influences in newborn infants. Constant vestibulospinal control, demonstrated in infants from the first few hours after birth, was directed toward reducing and increasing spinal motoneuron activity in response to vestibular stimulation of all types. Predominance of inhibitory vestibulospinal influences, especially in the initial phase of movement, is related to the type of stimulus and topography of the responses tested. Only inhibitory vestibulospinal influences were observed in children during the first few hours of life.