Reticular formation. Interrelation with motor reactions

Reticular formation of the brain stem is a reticular formation, a set of nerve structures located in the central divisions (visual cusps, middle and oblong brain). The neurons that make up it differ in size, length of axons, and structure. There is a dense intertwining.

Functions of the reticular formation

Formation is associated with the cerebellum, spinal cord, bark in the cerebral hemispheres, limbic (providing the most important reactions in the body) system. In the area of the reticular formation, ascending (afferent) and descending (efferent) impulses interact. Pulses can also circulate through closed neural circuits. In this case, the neurons are constantly excited in the reticular formation at a certain level. As a result, there is a certain willingness to work in different departments of the central nervous system. The degree of excitation of the net formation is regulated by the cortex of the hemispheres.

The reticular formation includes areas capable of exerting an alleviating or inhibitory effect on spinal motor reactions.

For the first time, the dependence between spinal reflexes and stimulation of various sites of networked formation was revealed by IM Sechenov. Subsequently, the American neurophysiologist Magoun, with the assistance of the staff, clearly illustrated the observation of Sechenov.

Thus, with electrical stimulation of the medial region, the narcotized monkeys and cats underwent complete cessation of movements, both reflex and stimulation of the motor cortex of the cerebral cortex. In this case, all the inhibitory phenomena that are provoked by the reticular formation, which has been irritated, are two-sided.

When the net formation on the periphery, which exerts a retarding effect on the lateral zone, appears, a facilitating effect on the spinal motor activity is revealed.

The reticular formation is capable of affecting different spinal formations.

It should be noted that the net formation zone, which has a facilitating effect on motor activity, spreads anteriorly. Thus, it covers not only the area of the medulla oblongata, but also the midbrain and the variolium bridge.

Mesh formation can influence the muscle tone. This provision was discovered by R. Granit. The Swedish neurophysiologist has shown that the reticular formation affects the activity of gamma motor neurons. Their axons pass through the so-called "intragastric" muscle fibers and play an important role in regulating the phase movements and body postures.

Different regions of the reticular formation are capable of exerting generalized effects on the cerebral cortex, while involving all its regions.

Maintenance of the activity of net formation and sensitivity to various chemical elements circulating in the blood is carried out by means of humoral factors (carbon dioxide, catecholamines, etc.). This, in turn, contributes to the inclusion of the reticular formation in the regulation of individual vegetative functions.

It should be noted that the study of the relationship between reticular formation and other subcortical structures and its properties made it possible to clarify the mechanisms of the neurophysiological character of individual states (pain, wakefulness, sleep, active attention, emotional and motivational states, and others). The use of medicines in studies allows one to identify methods of treating certain pathologies of the central nervous system, to determine a new approach to certain medical problems.