Problem of the structural and functional organization of the immature motor center

A hypothetical structural and functional scheme of organization of the immature spinal motor center is proposed, based on our own studies carried out on rat pups of the first month of postnatal development as well as on the analysis of data from literature. Taking into account peculiarities of functioning of various chains of the segmental reflex apparatus (high excitability of the motor center, heterochrony in the development of interneurons of the spinal cord dorsal horns as well as of excitatory and inhibitory mechanisms, possibility of generation of rhythmic activity by one of the half-centers of the motor generator regardless of the activity of the other one) and the mechanisms of its cholinergic and catecholaminergic regulation, age-related changes are considered, which are connected with the organization of interrelations of elements both within the motor center and from the descending regulatory systems.