Movement levels. Sensory corrections and two cycles of interactions as a principle of motor system self-regulation in health and disease. The theory of skill education. Classification of movement disorders in cerebral palsy on the basis of a defective level of coordination.
Movement is a quality inherent in all living things, whether it is the flow of fluid in plants, blood cells in the vascular bed, the movement of animals and humans in space, or the socially determined actions of an individual.
The formation of movement, the improvement of its qualities, such as speed, accuracy, smoothness, etc., is the essence of a process that obeys the universal laws of the construction of movements. It is based on the improvement of coordination (joint - from Latin ordinatio - ordering, interconnection, alignment. In biology - the correlative development of organs and parts of the body in their historical development).
The laws of construction of movements were first defined by our compatriot N.A. Bernshtein in the forties and fifties. The encyclopedia reports: “Bernshtein Nikolai Alexandrovich (1896-1966) - neuro- and psychophysiologist, creator of the physiology of activity. His research in the physiology of movement theoretical basis modern biomechanics, some of his ideas anticipated a number of provisions of cybernetics”. Based on the laws he derived, the science of artificial control systems, manipulators, and robots developed. His scientific fate, unfortunately, resembles the fate of progressive biologists and geneticists of that time.
Bernstein's principles were then deciphered and concretized by many researchers (Anokhin P.K., Gurfinkel V.S., 1960, etc.).
Human movements have a beginning in their development, a period when the qualities of movement (speed, accuracy, etc.) reach perfection, and involution - fading, loss of these qualities.
This principle is most noticeable in the formation of locomotion, in particular, walking (locomotion - from the Latin lokus - place and motio - movement. In biology, this is a cyclically repeating regular sum of automatic movements that ensure active movement in space - walking, swimming, bird flight etc.).
We all watched how clumsy, inaccurate movements of a child of 1 - 1.5 years old become sweet and graceful in their own way by 3 - 5 years.
At the age of puberty, hormonal disturbances again make movements angular, sharp, awkward. By old age, the control mechanisms wear out, and movements become fussy, uncertain. Old man stomps for a long time before getting off the footboard of the bus, stepping over a puddle, as if trying on space. It is becoming increasingly difficult to maintain stability when walking, and an old man deliberately reduces the transfer period of the step, since leaning on one leg at this moment carries the risk of loss of stability - the gait becomes shuffling.
A huge influence of emotions on the pattern of movements is known: the walking of a prisoner and a winner is not comparable, although it consists of the same structural elements. Movements of a ballerina, mime is a silent expression of the whole gamut of feelings from tragedy to triumph, deaf-mute movements of hands and face replace speech. With movements, you can depict a dying swan and even melted ice cream and drying cheese.
Such perfection of movements is not inherited. The infant does not have the qualitative characteristics of the movements of the father and mother. He again goes through the whole path of development of movements - from the most primitive to highly coordinated and socially significant actions. What is this path, how is it connected with the development of brain structures and peripheral mechanisms, how does the development of a skill, the improvement of the qualities of movement - these questions are answered by the theory of construction of movements proposed by Bernstein. It includes several key points:
the first provision is about the unity of onto- and phylogenesis of movements; the second provision is about the stepwise development of movements, about the levels of construction of movements in the central nervous system;
the third provision is about the reflex ring and sensory corrections;
the fourth provision is about two cycles of interaction; the fifth provision is about the development of skill.
Let's take a closer look at each of these postulates.
Movement is a property common to the entire animal kingdom. Ultimately, this is a fight for life. It depends on the qualities of movement - “you will be eaten or you will be eaten”, which is the essence of the law of natural selection: the strongest survives, possessing high speed, agility, endurance, quick reaction, the ability to hit the target, protected by a shell, etc. Therefore, this is how The structures of the brain that control movement are complex, repeatedly duplicated at all stages of development, which is why the process of improving coordination mechanisms is so lengthy and thorough, and therefore, with local lesions of the brain by trauma or illness, movement, although it acquires a pathological character, does not disappear completely. Nature loses none of her earlier acquisitions in this process.
The formation of human movements, including locomotion, repeats phylogenesis in ontogenesis (ontogeny - from Greek ontos - existing and genesis - origin. In biology, ontogenesis is the process of individual development, phylogeny (from Greek phylon - clan, tribe) the historical development of the world organisms - species, classes, etc.).
In phylogenesis, the process of control, coordination of actions originates in unicellular organisms, where a signal of danger or the proximity of prey is transmitted by contact, which is chemotaxis (from the Greek chemo - chemistry and tachis - device). In biology, chemotaxis is the movement of the simplest organisms under the influence of changes in the concentration of chemical stimuli. The response to irritation is possible only in the immediate vicinity of the stimulus. The next stage of evolution is multicellular organisms. The mechanism for coordinating the functions of a multicellular system becomes more complicated. At this stage of development of regulation, each cell releases the products of its vital activity into the intercellular space, reporting information about itself to the entire system. This is a humoral way of managing, structurally and functionally more differentiated. A noticeable stage in evolution was the appearance of oblong forms of living objects. The appearance of this feature was the progress of evolution, since the oblong shape reduces the front of danger for the animal. But it also gives rise to a lot of problems in management, because the parts of the body that are posterior to the main - head - end must be protected and obedient, must be ready to perform a more complex motor task, i.e., more highly coordinated in their actions . To perform the motor tasks of this plan, evolution generates a remote way of perceiving an object - a receptor apparatus appears (from Latin receptor - receiving, receptio - acceptance). In biology, receptors are the endings of sensitive nerve fibers or specialized cells - the retina of the eye, the inner ear, etc., which convert irritation perceived from the outside (exteroceptors) or from the internal environment of the body (interoceptors) into nervous excitement transmitted to the central nervous system. Telereceptors (from the Greek She - far away) - receptors that receive signals at a distance - this is the mechanism of vision, hearing, etc. The appearance of telereceptors is considered as a leap, a revolution in the development of movements, since this is already the ability to see in advance prey or danger, to prepare for the performance of the corresponding motor task - to ensure one's safety or take possession of the victim. The task becomes more complicated, and at the same time the control and executive apparatus become more complex - the center of control centers appears - the brain, the musculoskeletal system is improved. N.A. Bernshtein writes that the appearance of the striated muscle in the phylogenesis was a mystery of evolution. This acquisition of nature had both positive and negative (in terms of management) consequences. Positive was the increase in power capabilities, facilitating the solution of complex motor tasks, the speed of responses, posture stability, endurance during prolonged work.
It became possible not only to move the body, but also to move with the help of the limbs - walking, flying, swimming, etc. Negative, if I may say so, was the need to complicate the control systems and the executive apparatus of movements - the muscular and skeletal systems. The structure of the muscle changes dramatically. The muscle is therefore called striated because it consists of alternating, distinct from each other, structural elements, visible microscopically as red and white transverse stripes.
Structure is driven by function. The muscle in terms of control works on the principle of “all or nothing”. Under these conditions, it is difficult to dose the effort adequate to the motor task to be solved (in fact, coordination), and nature endows the muscle with a fibrous structure, the ability to include not all fibers in the work, but what is necessary in this moment their number, and “shock absorbers”, which are connective tissue layers (white stripes between red ones), which ensure smooth movement. For the function of such a muscle, a rigid system of support and movement is needed - the skeleton. The skeleton performs not only a motor, but also a protective function (a tortoise shell, a skull that protects the delicate tissue of the brain from damage). The skeleton must be rigid, but at the same time very mobile, obedient, those. there is a need for movable and inactive joints that have the appropriate form for the function and a certain number of degrees of freedom for each joint.
The degree of freedom in biomechanics is the ability to move in a certain direction. For a block-shaped joint, two degrees of freedom are possible (for example, for a knee joint, this is flexion and extension).
At the same time, control mechanisms are also being improved. The central nervous system becomes more and more complex, more highly differentiated brain structures appear. The process of development of brain control structures is not unsystematic, not chaotic, but obeys completely definite laws. In the vast, multi-million world of brain cells, a hierarchy is built in a certain sequence and within strictly defined time limits of its formation - the subordination of lower brain structures to higher ones. Hierarchy (from the Greek hieros - sacred, ogsiyo - power) - the arrangement of parts or elements of the whole in order from higher to lower. In the theory of organization of functions, this is the principle of control.
We turn to the deciphering of the second position of Bernstein's theory, namely, to the concept of levels of construction of movements in onto- and phylogenesis. Earlier, the improvement of the mechanisms of the managerial and executive apparatus was briefly described. From a comparison of the biomechanical and neurophysiological characteristics of movements, in particular locomotion, Bernstein concludes that the differentiated movements of higher animals and humans are the product of improving the control mechanisms of lower organization.

Table I
Phylo- and ontogeny of regulation of movements (according to N.A. Bernshtein)

ny systems by creating structures, which he called the levels of construction of movements.
To decipher this position, he introduces the term function localization. Localization (from Latin lokus, lokalis - place, local), according to Bernstein, is a complex of brain structures responsible for performing a certain class of movements. The class of movements is the movements that are characteristic of an animal at a certain stage of its motor development. (Further on, this last concept will be characterized more broadly.) He emphasizes that the term of function localization is not a topic - the topographic anatomy of the brain (from the Greek topos - place, grapho - I write), and the function and morphological content embedded in this concept are similar on the function and arrangement of the blocks of panels of the radio receiver, when the individual parts of the whole are not necessarily always nearby, in the same place, as topographic anatomy dictates. Moreover, the maturation of the brain structures included in the concept of localization can be extended in time, when some elements are already ready to perform a function, while others are in the process of formation. This, apparently, can explain the great difficulty in educating certain movements, when a delay in the development of one of the elements of localization makes it impossible at the moment to educate some movement - be it playing the piano, skating or self-service skills. That is why it is advisable to start training in sports or learning the art of dancing and playing musical instruments at a certain age. This can explain the complexity, a huge spread, but also a certain pattern of pathology of posture and walking in cerebral palsy.
The difference between the concept of topic and localization is illustrated by an example when, with damage to certain brain structures, the patient cannot complete the “raise your hand” task, but when asked to take off his hat, he will quite easily and freely raise the same hand.
Based on the foregoing, Bernstein proposes a scheme for constructing movements or levels of coordination in phylo- and ontogenesis.
Each level of coordination includes an afferent system, a center, and an efferent system. (Afferent - from lat. afferens - bringing, efferent - from lat. efferens - taking out.) In biology, respectively, - transferring nerve impulse to the center or from the center to the working body.
We have compiled Bernstein's information about the scheme of building movement or coordination in a table (Table I).
In the scheme, for each level of coordination, the morphological substrate of the central nervous system, the age of its final formation, the afferent system, the class of movements organized by this level of coordination, and the specific elements of a person’s posture and locomotion introduced into the control of this particular level are indicated.

Levels of coordination of the prelocomotor period: rubrospinal, thalamo-pallidar. striatal-pyramidal, consisting of two sublevels - striatal and pyramidal.
This is followed by the levels of regulation of movements when locomotion is already formed: the parieto-premotor level (the level of objective actions and semantic goals) and a group of higher cortical levels that provide writing, speech, etc., the coverage of which is beyond the scope of this book.
Rubrospinal level - the most ancient - paleokinetic (from the Greek. palaios - ancient, kinesis - movement) - the level of coordination of movements.
Its name includes the Latin definition of the red nucleus of the brain (nucleus - nucleus, rubrum - red) and nuclei of the spinal cord (from Latin spina - ridge, in anatomy - spinal - spinal cord).
Its morphological substrate is the afferents of the vestibular apparatus, receptors of the skin, tendons, muscles and articular capsules, receptors of cross-reflexes of paired limbs and interlimb (from Latin reflekxus - turned back, reflected, in biology - the body's response to irritation of receptors), reflexes of internal organs: vasomotor, urinary, defecation.
It completes its development in utero. The class of movements provided by this level of coordination consists of movements of a swimming nature - slow or swift, continuous or suddenly turning into immobility, movements in which almost 100% of the musculature of the body is involved. Their character resembles the movements of fish.
The talamo-pallidar level is another mechanism for regulating movements, ready to function even before birth. Its name is due to Latin terms: thalamus - visual tubercle, in anatomy - the main part of the diencephalon, the main subcortical center, directing impulses of all types of sensitivity - temperature, pain, etc. - to the brain stem, subcortical nodes and cortex hemispheres. Pallidum (from Latin globus pallidum - pale ball) in humans regulates vegetative functions. This level provides the major tremendous synergy of walking with the rhythmic sequence of engaging almost 100% of the skeletal muscles. (Synergy - from the Greek sinergBs - acting together. In biology, synergists are muscles that act together to carry out one specific movement, for example, inhalation, in which intercostal, intercartilaginous and diaphragmatic muscles participate simultaneously.)
The thalamo-pallidar level, together with the rubrospinal level, provide a balance mechanism - antigravitational - and a certain character of fetal movements in the amniotic fluid of the uterine cavity.
It should be noted here that in works on anthropology (from the Greek. anthropos - a person, logos - a word, teaching) there is information that the age dynamics of the trabecular structure of the vertebrae speaks of the fetal spine as a functioning organ.
Curious from these positions is the discovery of American scientists, who proved that the fetus 8 - 12 weeks already hears. This interesting fact would be established as follows: the father of the child, pressing his head to the mother's stomach, hummed the same melody. After birth, the baby always clearly reacted to this melody, calmed down and stopped crying.
Clinicians are well aware that the buckling movements of the fetus occur at very specific times of its development so clearly that the time of movement is one of the criteria for determining the gestational age.
It can be assumed that a child with a complicated birth who will be diagnosed with a child cerebral paralysis, the most ancient mechanism for coordinating movements is already defective. In this case, many features of the course of pregnancy and childbirth will become clear, such as late fetal movement, its incorrect position (transverse, etc.) in the uterine cavity, incorrect insertion of the head when passing through the birth canal, entanglement with the umbilical cord, one end of which motionlessly attached to the wall of the uterine cavity (for example, a small puppy tied to a booth, wrapped in a chain, may die), fast or, on the contrary, slow births, premature or late births. All of these signs are often noted in the anamnesis of children with cerebral palsy. This idea is also suggested by the fact that movement disorders in cerebral palsy, with all their diversity, are classified into certain groups in which the pattern of movements is of the same type. Yes, and it is difficult to assume that obstetricians in Russia, the USA, India, etc. are equally careless in obstetric care.
From these positions, birth injuries - peripheral paralysis of the hands, fractures of the clavicles, hematomas and other complications could be considered not as a cause, but as a consequence - a consequence of a disturbed program of fetal movements. Based on this, it would probably be necessary to study, using ultrasound or other methods of research, the patterns of fetal movements, their pattern, and if signs of risk are found, offer a caesarean section instead of stimulating the labor activity of the uterus, which in this situation will only increase fetal hypoxia.
The afferent system of this level of regulation is the receptors of the vestibular apparatus, which are designed to signal the position of body parts in space (otolith apparatus) and the speed and direction of movements (semicircular canals of the inner ear). The labyrinth system, the red nucleus, the optic tubercle, as well as the nuclei of the cerebellum are normally formed by the time of birth and can fully function.
There is reason to assume that complications during pregnancy and childbirth may come from the defectiveness of the structural elements of the rubrospinal and thalamo-pallidar levels of movement construction, expressed in varying degrees of severity and causing further pathogenesis of posture and walking deformities in a child with cerebral palsy after his birth. The baby is born "thalamo-pallidar" and the movements of the newborn are dictated by this matured level of coordination. The class of movements regulated by the rubrospinal level of coordination is superimposed by movements of the class of the thalamo-pallidar level. At the same time, nature does not lose its early mechanisms of coordination, and each next, more highly differentiated level changes the characteristics of movement in the direction of their complication, improvement in accordance with a more complex motor task, while using the expedient elements of a more primitive class of movements.
So, smooth, alternating with immobility, continuous movements of the rubrospinal level (similar to athetoid hyperkinesis) pass into the area of ​​vegetative functions, such as intestinal motility, contractions of the vascular wall, the work of the sphincters of the bladder and anus. The stepping synergy of the thalamo-pallidar level of coordination, which includes almost the entire skeletal muscles, serves as the foundation for the organization of bipedal walking, instead of the many-legged and trunk locomotion of lower animals (Table I). In the evolution of higher animals and humans, nature also uses such primitive methods of control that are characteristic of unicellular organisms. An example is the movement of blood cells in the vascular bed. Studies have shown that this is not a process of passive movement of cells in the blood plasma flow, but active, regulated movements of blood cells.
As follows from the scheme, global flexion synergy belongs to the class of movements of the thalamo-pallidar level. Clinically, it looks like this: if you ask the patient to bend one leg at the knee, automatic flexion always occurs simultaneously in the hip, knee and ankle joints of both legs (Fig. 1 A, B). Isolated movement is not possible. When kneeling, the patient falls forward or cannot assume a vertical kneeling position at all, folding like a penknife, but can nevertheless maintain an upright torso position in a sitting position with bent legs.
With a severe degree of defectiveness of this level, a person cannot sit down on his own, planted, does not hold a sitting position.
Tracing the evolution of the child's movements, one can observe that up to a certain age a healthy child cannot perform this task either, but then, along with the maturation of the structures and the striatal level following it in the hierarchical ladder, motor synergies seem to be localized, limited in the volume of functioning muscles and joints, and thus more differentiated and expedient postures and movements become possible. Such differentiation is possible with the maturation, as mentioned above, of the striatal level of coordination, when stepping synergy begins to correlate with the features of space - obstacles, uneven ground, steps, etc. Striatum - from lat. korpus striatum - striatum. In anatomy - highly diffe-

A. Patient with global flexion synergy. An attempt to flex in the right knee joint is accompanied by synergistic flexion in the hip and knee joints, dorsiflexion in the hip and knee joints, dorsiflexion of the feet and an increase in the depth of the lumbar lordosis. Isolated movement is not possible. B. EMG of the flexor muscles of the left leg. An attempt to flex in the right (contralateral) knee joint is accompanied by high electrical activity of the flexor muscles of the left leg.

a regressed formation of the brain, which plays the role of a regulator and brake of the gross reflex activity of the pallidum. It is known that a child who is just starting to walk still “does not know heights”, does not step over obstacles, etc.
Global, large-scale motor synergies are being replaced by more localized ones. This process normally ends by 2 years of age. A sign of the localization of this kind of motor synergy is the so-called Strümpel's tibial synkinesis, which he described in the 1920s. He regarded it as a neurological symptom that serves as a differential sign of damage to the pyramidal tract. The pyramidal level of regulation of movements, according to Bernstein, is the next after the striatal one, i.e., Shtrumpel's data indirectly confirm the validity of the classification of the levels of construction of movements.
Strumpel's tibial synkinesis is clinically interpreted as automatic dorsiflexion and supination of the foot with simultaneous plantar flexion of the first toe of this foot. An analysis of the electromyographic and biomechanical structure of walking allows us to state that the indicated synkinesis (from the Greek sun - together, kinema, kinematos - movement) is an element of locomotion healthy person and. serves to transfer the foot over the support. It becomes clearly visible only in extreme situations: at a high pace of walking, when overcoming sudden obstacles.
With inadequate control of the pyramidal level of coordination, tibial synkinesis, not being limited in the amplitude of the previously indicated movements and the time of their manifestation within the expedient, becomes pathological and causes such features of the posture and walking in cerebral palsy as instability of the ankle. joint in the sagittal plane, a significant weakening of the back push when walking, the posture of the so-called triple flexion when standing.
The pyramidal level completes the prelocomotor period of development of coordinations. This level introduces its semantic meaning into the movement (go there, bring something, etc.). A sign of the formation of this level in locomotion is the ability to produce an isolated movement.
With insufficient pyramidal level of coordination, as indicated above, it is difficult or even impossible, for example, dorsiflexion of the foot. When asked to do only this movement, its isolated flexion occurs in a minimal amount, and when the command “bend the knee” the foot automatically bends sometimes until the back of the foot touches the surface of the lower leg. A similar situation is also observed in an electromyographic study, when the maximum EMG amplitude during automatic flexion of the foot in the presence of tibial synkinesis is twice as high as the maximum EMG amplitude during an attempt to perform isolated dorsiflexion of the foot (Fig. 2 A, B, C).
The pyramidal level of coordination matures by the age of two, and with the end of its maturation, locomotion is formed in full.

Rice. 2 (A, B, C) - A patient with Strumpel's tibial synkinesis.
A. Arbitrary isolated dorsiflexion of the left foot is minimal (within 10°). B. An attempt to bend the knee of the left leg is accompanied by automatic dorsiflexion of the foot of this leg. C. EMG of the tibialis anterior muscle during an attempt to produce maximum dorsiflexion of the foot of this leg (upper curve). EMG of the anterior tibial muscle is significantly increased in amplitude when trying to bend the knee of the same leg (lower curve).

me. Consequently, the scheme for constructing movements gives us an idea of ​​the process of the stage-by-stage organization of locomotion, and for each level it is possible to determine a differential feature. Thus, for the thalamo-pallidar level it is a global flexion synergy, for the striatal level it is Shtrumpel's tibial synkinesis, for the pyramidal level it is an arbitrary isolated dorsiflexion of the foot. Even after these levels are finally formed, locomotion does not freeze in its development, its elements undergo changes caused by hormonal disturbances during adolescence or dilapidation, deterioration of coordination mechanisms in old age, as well as damage caused to the brain by trauma or illness. In this sense, the pathology of posture and walking in cerebral palsy can be interpreted as the result of the development of initially defective brain structures responsible for coordination at each stage of locomotion ontogeny.
Bernstein's next postulate is the principle of a reflex ring, or otherwise - feedback, or the so-called sensory corrections (sensory - from Latin sensus - perception, feeling, sensation). These formulations define the same concept.
Bernstein for the first time introduces the concept of a reflex ring as a form of feedback into neurophysiology, having entered into a dramatic discussion for himself with the great Pavlov, who built his theory of organization and improvement of function on the concept of a reflex arc, thus excluding feedback.
Movement is, according to Bernstein, two cycles of interactions: peripheral and central (Fig. 3).
The peripheral motor apparatus carries out its activities through complex interaction with the external environment. The measure of muscle tension depends both on the innervation state of the muscle and on the value of the articular angle, i.e. from the instantaneous position occupied by the system of links. It follows from this that muscle tension is one of the causes of movement, since it is a force that is applied to the link and forces it to change its position. On the other hand, the movement of the links, accompanied by a change in the articular angles, changes the distance between the points of attachment of the muscles and thereby causes a change in its tension. Here there is a cyclic form of interaction characteristic of physiology: muscle tensions affect the course of movement, and movements affect muscle tension. Such cyclic interactions are well known in mechanics and are expressed in mathematical language. Above the peripheral system of cyclic interactions, another one is built, the activity of which is also cyclic.
This is the central nervous system with all its numerous apparatuses. Here they have taecTO interactions of a different order. First of all, the primary effector impulse from the command device, directed from the CNS through the cells of the anterior horns to the muscular system, sets the latter in motion or changes the state of its movement. This movement or change in movement is perceived by the nerve windows

tendons, muscles and articular bags, which belong to the proprioceptive nervous apparatus. They transmit information about changes in movement through affector pathways. Considering this impulse, as well as visual, auditory, the CNS sends a new impulse, making adjustments to the initial motor impulse, i.e., there is a cyclic nature of interactions, which indicates a reflex ring, the presence of feedback or sensory correction.
The passive motor apparatus consists of movable bone links that form kinematic chains, which are characterized by degrees of freedom of mobility.
The transition from one degree of freedom to two or more marks the emergence of the need for choice. An automatic continuous expedient choice becomes necessary.
The kinematic chain will become controllable only if it is able to assign certain trajectories of motion that we desire for each of the elements of the chain and make these elements move along the assigned path.
“In overcoming the excess degrees of freedom of a moving organ, i.e., in turning the latter into controlled system, and is the task of coordination of movements. Bernstein calls the principle of coordination the principle of sensory corrections.
The foregoing fully explains why disorders in the effector apparatuses of the CNS, as a rule, do not lead to pure coordination disorders, giving only syndromes of paralysis, paresis, contractures, etc., and why malfunctions in the afferent systems necessarily cause movement disorders of the atactic type. , i.e. coordination disorders.
All forms of organic coordination disorders known in the clinic are always associated with diseases of the receptor apparatus and their pathways: vestibular apparatus (labyrinth or vestibular ataxia), posterior columns of the spinal cord, conducting proprioceptive and tactile impulses (tabetic ataxia), cerebellar reciprocal systems (cerebellar ataxia) .
In a person, compensations are possible that can overcome organic ataxia to one degree or another. They are always carried out by including a new type of sensitivity (visual, auditory, etc.) in the motor process.
All types of afferentations of the body take part in the implementation of sensory corrections in different cases and to varying degrees.
Using the terminology of Sherrington, Bernstein calls the entire set of receptor functions of this kind "propriocepticon" in a broad functional sense.
This is a system of sensory signals about postures, articular angles, speeds, muscle stretches and tensions. The muscle, causing by its activity changes in the movement of the kinematic chain, irritates the sensory endings of the proprioceptors, and these signals, closing in the CNS on the effector pathways, make changes to the effector flow (i.e., there is a reflex ring). Coordination in this sense is not some kind of precision or subtlety of effector impulses, but a special group of physiological mechanisms that create a continuous organized cyclic interaction between the affective and effector processes.
Since every movement that has real meaning overcomes internal and external forces on its way, its whole essence lies in the expedient struggle with them.
The motor task and the forces that must be overcome to solve it are dictated by outside world and beyond the control of the individual.
In order to correctly solve a motor task, it is necessary to verify it with the help of the senses throughout the entire motor act, from beginning to end, to monitor and control every moment: is the solution of the problem proceeding as it should, and every moment to make the necessary corrections. The mechanism of these motion corrections is sensory correction. A defect in one or another of the most important types of sensitivity for movement and the sensory corrections they provide leads to severe impairments in motor coordination.
Movement cannot be made on one internal laws the balance of excitations and inhibitions, because from the very first moment it will be violated by external forces unknown to the organism in advance and beyond its control, and the forces of mutual collisions and recoil in long and mobile chains of limbs, and the resistance of the external environment.
The role and activity of the sensitive afferent systems of the body only begins from the moment they give the starting signal for the next movement. As soon as it begins, in response to the first effector impulses, afferent impulses appear in all sensitive devices of the motor apparatus (in the organs of muscular-articular sensitivity in the first place), signaling how the movement began and how it proceeded. These test sensory signals determine the necessary next sensory corrections in the brain.
Based on this, the fundamental form nervous process in the implementation of a semantic motor act, according to Bernstein, the form of a reflex ring appears.
When performing a motor task, sensitive systems provide two different functions: a signal-starting service and a service that controls the effect of movement and ensures its controllability.
The study of the control of integral semantic motor acts presented the afferent systems of the body in a completely different light. An analysis of the coordination construction of a motor act and its disturbances in pathology, the study of how movements are controlled in the order of a circular process such as a “reflex ring” showed that afferent systems signal the brain about the course of movement and provide the basis for sensory corrections not with “raw sensory signals, isolated from each other on the basis of quality (separately tactile, kinesthetic, visual, etc.), but vice versa. These perceptions, which provide control of movement, always have the character of whole complex syntheses, deeply worked out by the brain complexes of the most diverse sensations, fastened also by numerous traces of former sensations, preserved by memory, impressions of former movements in space. “The more complex the motor task, the more complex and further from the primary raw sensations is the sensory (sensory) synthesis that serves this level, the more internal brain processing, comprehension, ordering and even schematization of the primary sensations that are generalized in it.”
All successive evolutionary complication and enrichment of sensory syntheses proceeded along the line of eliminating distortions and inaccuracies of individual sense organs, ensuring the reconciliation of their testimony, and comprehension.
All successively formed levels of construction of movements (as the modern physiology of motor acts also designates them) have a very different evolutionary age, have been preserved in humans, having formed a whole hierarchical ladder of mutual subordination, and the topmost of them belongs exclusively to humans (the level of speech and writing) . The most ancient lower levels, formed in animals with their brain substrates and lists of motor tasks feasible for them, have been preserved in humans and continue to control the most ancient, semantically primitive motor acts (swallowing, swimming, walking, etc.).
“At the beginning of the formation of a new individual motor skill, almost all corrections are surrogately carried out by the leading level - the initiator, but soon the situation changes, each of the technical aspects and details of the complex movement being performed sooner or later finds for itself among the lower levels one whose afferentations are most adequate to this detail in terms of the qualities of the sensory corrections it provides. Gradually, as a result of a series of successive switchings and jumps, a complex multi-level construction is formed, headed by a leading level, adequate to the semantic structure of the motor act and realizing only the most basic corrections that are decisive in the semantic sense. “Under his conducting, in the execution of movements, a number of background levels are involved, which serve the background or technical components of the movement, tone, innervation and denervation, reciprocal inhibition, complex synergies, etc.” (N.A. Bernstein).
The process of switching the technical components of traffic control to the lower, background levels is what is usually called traffic automation.
In any movement, whatever its level height, only one leading level is realized.
The essence of the automation process, which sometimes requires a long time and persistent exercise, lies precisely in the development of the CNS plan for the background layout described above, in determining the motor composition of the movement.
Determining the motor composition is sometimes referred to by neurologists as “projecting a movement”.
Initially, to maintain a stable step length, the child uses proprioceptive mechanisms and makes a “post factum” correction, then a more advanced method of “ante factum” correction comes in (from Latin post and ante - after and before the fact, respectively).
The phenomenon of preliminary corrections is in all cases a later and more perfect form of coordination than the mechanism of secondary corrections.
At the beginning of mastering the movement, the beginner strains all the antagonist muscles, disables all degrees of freedom in advance and with a margin, leaving one or two movements most necessary for this base.
At the next stage of the exercise, having already become accustomed to it, when and in what direction the next push of the reactive force will befall him, the subject allows himself to gradually, one after another, release the freedoms that are fixed to that degree in order to prevent reactive forces, which gives a sharp energy saving, i.e. e. struggles with reactive forces. In the third stage of the development of movement, the struggle against reactive forces is of a different nature, when they are transformed from hindrances into useful forces.
Sensory corrections are a stimulus both in the process of the formation of movements and in the process of their further improvement in the age aspect. Moreover, Bernstein defines the process of organizing movement within his class as evolutionary, and the transition to a new class of movements, due to the emergence of a more differentiated level of coordination, as revolutionary, spasmodic. Movements of a higher level of regulation appear within the lower organized class, reach a maximum of development, and signs of previous movements that are irrational from the point of view of a new motor task are forced out.
For example, motor automatisms of global flexion synergy are gradually replaced by more localized automatisms of tibial synkinesis. At the same time, the biomechanical and electrophysiological characteristics of walking change, allowing you to perform more complex motor tasks, such as differentiation of the phases of the reference period of the step, the ability to overcome soil irregularities, a higher pace of walking, etc.
Ultimately, it is sensory corrections that solve these problems. After all, the executive muscular apparatus, all muscle work is controlled by impulses coming from the cells of the anterior horns of the spinal cord, according to the principle: an impulse is a muscle contraction. All coordination “showdowns” (with what force the muscle contracts, when, for how long, etc.) occur at the supraspinal levels - at the levels of coordination indicated by Bernstein, that is, up to the cells of the anterior horns of the spinal cord. Thus, according to neurological terminology, the “final path” is one for all the diversity and complexity of the suprasegmental apparatus of the CNS.
Posture, walking characteristics, therefore, are formed at supra-segmental levels, and sensory corrections are the instrument of this process.
This principle is very important in the sense that with cerebral palsy, i.e. with central paralysis, it is apparently unjustified to talk about the loss of muscle strength as a reason for limiting the range of motion in the joint (this is typical only for peripheral paralysis, where interrupted or the final - efferent - path is damaged), but we should talk about a violation of coordination of movements - discoordination, dyskinesia (from the Greek dys ... and lat. dis ... - a prefix meaning difficulty, violation, loss of something). From these positions, it is logical to consider the essence of the methods of orthopedic correction of posture and walking in cerebral palsy.
All the means used by orthopedics are intended to ultimately affect the nature of sensory corrections, whether it is a decrease in the flow of sensory impulses when fixing the joint with a splint or orthopedic apparatus, or the use of cold to increase the flow of impulses. The latter is achieved, for example, by the Michel La Mathieu method, when, with flexion contracture of the wrist joint and finger joints, further rather strong and prolonged flexion performed by the doctor and enhancing the afferent flow causes an increase in the volume of extensor movements. The same role is played by the so-called medical load suit - the suit of astronauts, proposed for use in cerebral palsy. With the help of longitudinal elastic bands, going from the shoulder girdle to the waist and from the waist to the feet, sensory impulses are enhanced in the coordination structures of the brain responsible for the regulation of antigravitational functions. Indeed, when using the suit, we observed a significant increase in the stability of the posture and walking of children with cerebral palsy. Although it should be noted that in this case, it is impossible to exclude inappropriate biomechanical compensations to increase the stability of the posture, such as changing the depth of the curvature of the spine, strengthening imitative synkinesis, etc.
Surgical intervention also significantly affects the flow of sensory impulses: myo- and tenotomy (from Greek mfs - muscle, tome - segment, tendo - from Latin - tendon; in medicine - dissection of muscles and tendons), arthrodesis (from Greek arthron - joint, de - from Latin and des - from French - absence) exclude movements in the joints and practically stop the flow of proprioceptive impulses. This explains the antispasmodic effect of operations for cerebral palsy, extending far beyond the area of ​​intervention. Sometimes one dissection of the rectus femoris muscles with rectus syndrome normalizes the entire posture.
Muscle transplantation also changes the afferent flow, thus intervening in the mechanism of sensory corrections. This provision forces a stricter approach to indications for surgical operations in the age aspect. Global synergy, for example, makes the effect of any operation difficult to predict, as well as the combination of equinus with tibial synkinesis.
The most favorable result is in patients with cerebral palsy with insufficiency of the pyramidal level of regulation, i.e., when the prelocomotive period has basically completed its formation and we practically do not predict the result of “talamo-pallidar patients” with cerebral palsy, since the period of locomotion formation has just begun its development.
These and other complications will be discussed in more detail in the chapter on the principles of surgical correction of posture and walking in cerebral palsy.
Sensory corrections are the basis of not only the organization of movements in ontogeny, but also the mechanism for their improvement, as evidenced by the theory of skill development in sports, work, and the organization of locomotion. N.A. Bernshtein in his theory highlights the main structural components of the locomotor act: the alternation of the support and transfer periods, the period of double support.
According to the principle of equality of action and reaction, the efforts of the legs are equal and opposite to the efforts of support reactions, i.e., the force effects of the supporting surface on the body of the walker. This is the vertical component of the step (see Chapter IV).
The most informative is the longitudinal component.
The force impulses that cause the movement of the leg during walking are by no means limited to one pair of simple reciprocal impulses for each double step.
When studying the development of running in children, it was found that normally, in children from 2 to 5 years, the organization of the transfer period begins and the greatest innovations appear in the proximal points of the leg, while the distal ones remain stable for a long time.
From 2 to 5 years of age, the longitudinal curves of the thigh show a complete restructuring of the transfer time while running, while the curves of the feet have not yet differentiated from walking even in the support period.
This prevailing course of evolution from top to bottom from proximal to distal points leads N.A. Bernshtein to the following physiological generalization. (Since this information is extremely important for an orthopedist, especially a surgeon who corrects posture and walking in cerebral palsy, it seems appropriate to quote the entire text of the author.) “It is extremely unlikely that the nervous dynamics of the distal muscles lagged so sharply (for whole years) proximal muscles. Much more likely otherwise. The proximal points of the leg (for example, the hip joint) are surrounded by a much more powerful array of muscles than the distal ones (foot), and at the same time, the moments of inertia of the parts of the link closest to the first ones are undoubtedly smaller than the moments of inertia of the distal links. Therefore, it is much easier for the muscles of the hip group to move the upper segments of the thigh from their place than the foot, for the displacement of which they have to move the entire inert leg from top to bottom. Related to this is also the fact that the (relative) velocities of the distal links are, as a rule, higher than the proximal ones. Consequently, the former have more kinetic energies and it is more difficult to overcome them. The distal links play a role in relation to the entire leg, reminiscent of the role of a heavy pendulum.
It follows from this that, given its strength, it is incomparably easier for a nerve effector impulse to slip into the proximal curve and be reflected in it in the form of a noticeable dynamic wave than to be able to break through the entire thickness of the inertial resistance of the distal system. In order to be felt in the latter, the effector impulse must have a significant strength, or else it must arrive "on time" - at a moment when the distal system is in especially favorable conditions for its perception.
It is still difficult to say what this favorable moment can be expressed in, and here, apparently, a large field for research opens up: maybe it’s just the advantageous posture of the limb that matters here, which provides the muscles with the greatest biomechanical efficiency of action, maybe this favorable moment exists. crucial moment speed, when the inertial resistances are the least noticeable, perhaps, finally, this is the moment of a particularly receptive adjustment of the muscular apparatus, created here by one or another confluence of proprioceptive signals.
One way or another, the control of the distal links requires greater dexterity, a higher coordination technique in the sense of the ability to improve the right, optimal moment, to give just the right impulse just at the right time. If this time is missed even for a fraction of a second, then the impulse will no longer “pass”, i.e., it will not give any noticeable effect on the periphery.
It should be noted that we are not talking about small coordinated movements of the distal segments like finger movements, but about global, extensive, extrapyramidal type displacements of the distal limb segments. The dynamics of these latter ultimately depend on the same hip muscles as the dynamics of the proximal points of the leg.
But the distal dynamics becomes richly divided into biodynamic details not when these details appear in the effector impulse and begin to be reflected in the dynamics of pliable proximal points, but only when the functional attunement of the effector and receptor is established and when the effector n.s. learns to capture fleeting moments of functional conduction. Dynamic dismemberment is accompanied especially great wealth power “overflows” in the distal links, indicating a very fine control of the dynamics of the external, biomechanical order.
In a complex multi-link pendulum, such as a leg in the biomechanical sense, the dynamic interaction of the links, the play of reactive forces, complex oscillatory chains, etc., are very diverse and abundant. And the fact that they are not obscured by a trained master, but are reflected in such an abundance in dynamic curves, speaks of a very fine reactive adaptability of the neuromotor apparatus to proprioceptive signaling.
A higher degree of dissection of the distal force curves is a sign of the ability to catch the moments of least resistance, in other words, to most fully utilize both the entire external rich play of forces and, possibly, the entire physiological (involuntary) range of reciprocal and other, more complex reactive processes on the muscular periphery.
This material, which is relatively difficult for the clinician, is cited to emphasize that surgical extremism in matters of transplantation and lengthening of the muscles that control movements in the joints of the feet in children with cerebral palsy is hardly justified until the walking stereotype is finally formed. It should be noted at the same time that the motor development of a child with cerebral palsy almost always lags behind by 2-3 years. If we take into account Bernstein's information, walking and running normally mature by 5 years.
Further, the author states the presence of three steps of walking involution in the age aspect.
1. Decreased function of the structural mechanisms of walking, but greater control of consciousness.
2. Wary consciousness is replaced by fussiness, small step movements.
3. Explicit disintegration of motor structures.
The splitting of the previously unified coordination is noted.
Thus, the ontogenetic material showed with certainty that the dynamic structure of walking arises, passes through a series of regular stages of development, and involutes just as naturally in old age.
What is most important in principle here is that this development is associated with very distinct qualitative shifts in the very structure of walking.
In terms of morphology, this structure passes in early ontogenesis through:
a) the stage of the reciprocal innervation primitive;
b) the stage of gradual development of morphological elements;
c) the stage of excessive proliferation of these elements;
d) the stage of reverse development of infantile elements and the final organization of an integral and proportionate form.
“With regard to motor coordination, the biodynamic structure of walking also passes through a number of qualitatively different stages of development: at the very beginning, there is a symptom of hypofunction of proprioceptive coordination in general, then follows the stage of development of proprioceptive coordination post factum (compensatory or secondary coordination).
Much less often, ante factum coordination develops (dosing or primary coordination), which is organized much later.
So, Bernstein's theory of the construction of movements gives an idea of ​​the neurophysiological and biomechanical structure of the movement in the process of its formation and improvement. It includes fundamental provisions:
1. The ontogenesis of human movements repeats phylogenesis, which allows us to speak about the universality of the scheme for constructing movements proposed by the author, and, therefore, the validity of applying these laws to various disorders in the human motor sphere, including cerebral palsy.
2. The level of coordination is morphologically strictly marked and includes certain structures of the brain, afferent and efferent receptor systems capable of regulating specific classes of movements.
3. The qualities of movements are not inherited, but acquired. Improving the qualities of movement is a process consisting of stages of maturation of brain structures that coordinate certain classes of movements specific to this level. This process has a stepwise character. The totality of the complex of brain structures of coordination and the class of movements specific to it, Bernstein calls the level of construction of movements. For each class of movements, we have defined a sign - an indicator specific to this class of movements.
For the thalamo-pallidar level it is a global flexion synergy, for the striatal level it is Shtrumpel's tibial synkinesis, for the pyramidal level it is the ability to produce an arbitrary isolated dorsiflexion of the foot, an isolated movement of the fingers.
4. In ontogenetic development, nature uses all previously acquired mechanisms of coordination from primitive ones, which in humans pass into the sphere of vegetative science, to HIGHEST social actions. From each class of movements, nature in ontogeny uses elements that are appropriate for the performance of a motor task by inhibiting movements that are not needed for a new, more complex coordinating task. This function is performed by the next, more highly organized level of coordination.
5. The basis of coordination is the mechanism of sensory correction, two cycles of interaction and the mechanism of skill development.
6. Comparative analysis qualitative characteristics of movements in the process of their ontogeny in the norm and clinical symptom complexes of postural and walking disorders in cerebral palsy allow us to draw clear parallels. Based on this, there is reason to believe that cerebral palsy is not a disease with a residual stage, but the result of the maturation of an initially defective brain, which manifests itself already in utero. The similarity of movements of a certain class and the symptoms of movement disorders in cerebral palsy allows us to classify the pathology of posture and walking in cerebral palsy according to the defective level of coordination, while taking into account the sufficient conventionality of this scheme.
7. The child is normally born "thalamo-pallidar". During the first two years, he goes through two more stages of the prelocomotor period of development of coordinating mechanisms - striatal and pyramidal. In children with cerebral palsy, the pyramidal level does not reach its full maturity. The more late and more defective the maturation of the brain structures responsible for the coordination of motor functions takes place in a given patient, the more difficult it is to predict the result of treatment and the more cautious, apparently, one should approach the appointment of radical, in particular surgical, methods of treatment.
8., The prelocomotor period completes its development by the age of 2 in the norm. This means that all the elements necessary to maintain a stable upright posture and walk are available. Nevertheless, Bernstein points out that such components of locomotion as the support phases, elements of running, complete their development by 3 years, and all components of normal locomotion - by 5 years. Children with cerebral palsy are significantly behind in the development of motor skills - by 2 and 3 years. In this regard, it should be noted that the prognosis of any surgical intervention in children under the age of 6-7 years is difficult and the result does not always coincide with the desired one.

All human actions are expressed in movements.

Movement is a complex of psychophysiological functions implemented by the dynamic apparatus of a person.

Thanks to movements, a person affects the world and changes it, but the movements themselves also change.

Rubinstein emphasizes: human movements are the ability to perform an action aimed at solving a specific problem. The nature or content of the task determines the movement.

Since the time of Sechenov, arbitrary and involuntary have been distinguished.

The main properties of the movement:

1. Speed;
2. Force;
3. Pace
4. Rhythm
5. Accuracy and Accuracy
6. Plasticity and dexterity

Types of movement

Rubinstein highlights 6 types of movements:

1. Movement of the posture (muscular apparatus) - static reflexes that provide maintenance and change in the posture of the body;
2. Location movement(associated with movement) - features are distinguished in gait and posture;
3. Expressive movements of the face and the whole body(facial expressions and pantomimics);
4. Semantic movements(e.g. hat removal, handshake);
5. Speech as a motor function(dynamics, rhythm, intonation, stress);
6. labor movement - movements that exist in various types of labor operations.

developed the problem of the mechanisms of organization of human movements and actions. Before him there was classical physiology. Bernstein created non-classical physiology.

The difference between classical and non-classical physiology:

1. Classical physiology relies on the mechanism of the S-R model;
2. Classical physiology is the physiology of animals, where the principle of reactivity contributed. She had little contact with practice. Non-classical physiology turned to the study of man. object studies were the natural movements of a normal intact organism.
3. Bernstein's physiology was based on the principle of integrity. He argued with Pavlov that a reflex is not an element of action, but an elementary action, an integral act that begins and continues to completion.
4. Bernstein contrasted the principle of reactivity with the principle of activity. That is, all processes of reception (acceptance of energy) and centers that process information are a manifestation of activity.

Book published in 1947 "On building a movement".

In 1966, the year of death Alexander Nikolaevich Bernstein, his last book was published "Essays on the physiology of movements and the physiology of activity" where the concept is presented.

The concept of "model of the required future"

Alexander Nikolaevich Bernstein introduced the concept of a "model of the necessary future", considering it as one of the forms of displaying the world by a living organism. The second form is the reflection of the past and present. Along with this, the brain “reflects” (constructs) the situation of the future, which has not yet become a reality, which its biological needs encourage to realize. Only a clear image of the required future can serve as a basis for formulating a problem and programming its solution.

Unlike the model of the future, the model of the future has a probabilistic character.

The principle of sensory corrections

Bernstein suggested completely new principle movement control, calling it the principle of sensory corrections. This refers to corrections made to motor impulses based on sensory information about the course of movement. The result of any complex movement depends not only on the actual control signals, but also on a number of additional factors. The common property of these factors is to make changes in the planned course of movements. Movement, even the most elementary, is always built "here and now", and does not follow automatically - every time the same thing - after the stimulus that caused it.

The ultimate goal of a movement can only be achieved if it is constantly amended (corrections). The central nervous system must know what the real fate of the current movement is, that is, it must continuously receive afferent signals containing information about the actual course of movement, and then process them into correction signals.

Factors affecting the course of movement:

1. Reactive forces- involuntary reactions that occur in the systems of muscles, tendons, bones, and so on. If you wave your hand strongly, then reactive forces will develop in other parts of the body, which will change their position and tone. For example, if a child climbs onto a sofa and starts throwing the ball from it, then by throwing the ball, he himself can fly off the sofa.
2. Inertial forces- if you raise your hand sharply, then it will take off only due to those motor impulses that are sent to the muscle, but from some moment they will move by inertia (that is, longer than necessary).
3. Outside forces(external resistance) are obstacles that can get in the way of a running program. If the movement is directed towards an object, then it necessarily meets with its resistance, which is not always predictable.
4. Initial state of the muscle- (this is the position of the hand, the degree of contraction of the muscle, etc.) the state changes in the course of movement along with a change in its length, as well as as a result of its fatigue, etc. Therefore, the same control impulse, having come to the muscle, can give a completely different motor effect.

The action of all these factors necessitates continuous accounting of information about the state of the motor apparatus and the direct course of movement. This information is called "feedback signals" . Feedback signals from movements are often paralleled, that is, they arrive simultaneously through several channels. For example, when a person walks, he feels his steps with the help of a muscular sense and can simultaneously see and hear them.

Levels of construction of movements

Bernstein is the creator of the theory of movement levels. He discovered that, depending on what information the feedback signals carry, afferent signals come to different sensory centers of the brain and, accordingly, switch to motor pathways at different levels.

The level should be understood as morphological "layers" in the CNS. Thus, the levels of the spinal and medulla oblongata, the level of subcortical centers, and the levels of the cortex were identified.

Each level has specific motor manifestations peculiar only to it, it implements its own class of movements.

Level A- the lowest and phylogenetically the most ancient ( rubrospinal). To this level signals from muscle proprioceptors(receptors located in the muscles of the body), reporting on the degree of muscle tension, as well as from the balance organs.

Level A participates in the organization of any movement together with other levels and almost never leads a person. There are movements that are regulated by level A independently: involuntary trembling, chattering of teeth from cold and fear, trembling of a violinist's finger, and so on.

Level B- Bernstein called level of synergies(from Greek acting together; synergists are muscles that act together to carry out one specific movement). By the name of the anatomical substrate, it is called talamo-pallidar. At this level signals are processed from muscle-articular receptors that report on the relative position and movements of body parts.

Level B participates in the organization of movements of higher levels, taking on the task internal coordination, highly coordinated movements of the whole body. It is responsible for the automation of various motor skills, expressive facial expressions and pantomime movements, expressively colored. The own movements of this level include those that do not require consideration of external space: freestyle gymnastics, sipping, facial expressions, etc.

Level C- Bernstein calls the level of the spatial field. By the name of the anatomical substrate - pyramidal striatal. They apply to him signals from sight, hearing, touch, that is, all information about the external space. These are all moving movements: walking, climbing, running, jumping, various acrobatic movements, ball throws, playing tennis, aiming movements (playing billiards, aiming a telescope).

Level D - level of substantive actions. This is cortical level. By the name of the anatomical substrate - parieto-premotor. He is in charge of organization of actions with objects and is specific to a person. It includes all gun actions, all everyday movements, work, driving. The movements of this level are consistent with the logic of the object. This is not so much a movement as an action. They do not fix the motor composition, but set the final result. For this level, the method of performing an action, a set of motor operations is indifferent.. For example, a bottle can be opened with a corkscrew, the cork can be knocked out by hitting the bottom, the cork can be pushed in, etc. In all cases, the result is the same.

Level E - the level of intellectual-motor acts, primarily speech movements, writing movements, movements of symbolic speech (gestures of the deaf and dumb) . The anatomical substratum of movements at this level is not very clear, but Bernstein emphasized the involvement frontal cortex brain, referring to the work of Luria.

Should be considered:

1. Several levels are involved in the organization of complex actions at once. The one on which the action is built is called the leader, and the rest are the underlying ones.
2. Formally, the same action can be built at different levels. For example, a circular motion of the hands can be obtained at level A, or at level B, or at level C, or at level D.

What determines the fact of building a movement at one level or another?

The leading level of building a movement is determined by the meaning or task of the movement. That is, physiology is determined by completely non-physiological things, namely, the purpose of human action.

Thus, Bernstein introduced the target determination of the behavior of an organism.

Bernstein's contribution

Bernstein's ideas have great importance for psychology. He made major contributions to several branches of psychology:
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Part 14 -
Part 15 -
Part 16 - Actions and movements. Levels of construction of movements (according to N. A. Bernshtein)
Part 17 -
Part 18 -

The main provisions of the theory of the process of life is not a simple "balancing with the external environment", but an active overcoming of this environment; the process of building movements, in which there is not only direct, but also continuous feedback between the brain and executive organs;

to build movements of varying complexity, commands are given at various levels of the nervous system. When automating movements, control functions are transferred to a lower (unconscious) level; "repetition without repetition".

Conclusion 1, movement training does not consist in standardizing commands, not in “teaching commands”, but in learning to find and transmit such a command every time, which, under the conditions of each specific repetition of the movement, will lead to the desired motor result.

Conclusion 2 The movement is not stored ready in memory, but each time it is built anew in the process of the action itself, sensitively reacting to a changing situation. The memory stores not the clichés of the movements themselves, but the prescriptions for their construction, which are built on the basis of a mechanism not of stereotyped reproduction, but of an expedient adaptation.

Movement construction levels The physiological level of movement construction is a set of phenomena that mutually determine each other, such as: a) a special class of motor tasks; b) the corresponding type of corrections; c) a certain brain level and (as a result of all the previous); d) a certain class (list) of movements.

A person has 5 levels A - the level of tone and posture; B is the level of synergy (coordinated muscle contractions); C is the level of the spatial field; D - the level of subject actions (semantic chains); E - a group of higher cortical levels of symbolic coordination (writing, speech, etc.).

The main difficulties in controlling movements are the extraordinary richness of the mobility of the human body's motor apparatus,; the need to limit the huge excess of degrees of freedom; elastic compliance of muscle rods; many external forces that arise in the process of movement, the direction and intensity of which is difficult (and often impossible) to predict.

Motor skill formation Motor skill is such a degree of possession of the technique of action, when control is carried out with the leading role of consciousness, and the action itself is characterized by an unstable way of solving a motor task.

The characteristic features of the motor skill of movement control occur with the leading role of consciousness; lack of stability, constant search for ways to best solve a motor problem; low speed; low strength, instability to knocking factors; the inability to switch attention to the objects of the environment.

Factors of the initial ability to perform a motor action of already existing motor experience, previously developed coordinations, sensations and perceptions; the state of general physical fitness; knowledge of the technique of action and the features of its implementation; conscious attempts to build some new system of movements for themselves.

A motor skill is such a degree of mastery of the technique of action, in which the control of movements occurs automatically and the performance of the action is highly reliable.

Features of motor skills automated nature of action control; high speed of action; stability of the result of the action; extreme strength and reliability.

Phase determination of the leading level; determination of the motor composition of the skill; identification and painting of corrections; automation, standardization and stabilization of motor skills.

Stages of skill formation 1. The first stage: low speed, tension, inaccuracy of movements. 2. The second stage: the disappearance of tension, the formation of muscle coordination, an increase in the speed and accuracy of a motor act. 3. The third stage: a decrease in the share of participation of active muscular efforts in the implementation of the movement due to the use of reactive forces, which ensures the dynamic stability of movements and the economy of energy costs. During this stage, the phases of standardization and stabilization of the motor skill are realized. blocking excessive degrees of freedom of the kinematic chain. painting corrections and automation of control

A comprehensive theory of the formation of skills was developed by the outstanding Russian physiologist N. A. Bernshtein (1896-1966). This concept, called activity physiology, is based on the vision of the organism as an active purposeful system that has developed in the course of evolution, which is constantly directed towards the future and, accordingly, is guided by it in its actions. Bernstein's concept is based on three main principles.

The first one is the principle exercise. Bernstein noted that while technical devices wear out from the repeated performance of one or another action, living beings are characterized by exerciseability. This property of a living organism lies in the fact that each subsequent execution of an action is better than the previous one, i.e. it does not copy the previous one, but develops it. So, if you want to buy a car, then, of course, the best choice would be a new car. Conversely, when looking for a doctor, you are more likely to choose an experienced doctor.

The second principle is the principle "repetition without repetition" consisting in the fact that each new movement is not a blind copy of the previous one, but its development. According to Bernstein, living movement is a constantly improving system and therefore it cannot be described in mechanistic terms "stimulus-response". "No step is identical to another, even on smooth ground, let alone walking on rough roads," he wrote. Improvement of the movement occurs due to the constant comparison of newly incoming information with the available motor program and its change on the basis of this information. Such an understanding of the essence of motor activity led Bernstein to abandon the traditional concept of a reflex arc, developed by Descartes, and move on to the concept reflex ring. The essence of this transition lies in the fact that a skill cannot be a stereotypical sequence of learned actions; throughout its entire duration, constant verification of movement with real conditions is required. Imagine that you have solidified a sequence of movements corresponding to the skill of writing, in the following form: "first squeeze your fingers so that there is a gap of half a centimeter between the fingers, then turn your hand at an angle of 45 ° and begin to move it from left to right." It would seem that this sequence describes the beginning of the act of writing well. However, the handle may turn out to be larger than you expected during the training. Or you will have to write not on a flat table surface, but, for example, on a blackboard. It turns out that it is impossible to apply the sequence of actions worked out with such difficulty. However, we do write! The constant introduction of corrections to the movement based on the coordinating information that our sensory apparatus receives as the skill unfolds, the scientist called sensory adjustments.

And finally, the third principle of Bernstein's approach is the thesis that the essence of skill development lies in discovery of the principle of solving a motor problem, those. detection of movement parameters that signal how correctly it is performed, and this decision takes place in several stages.

At the first stage, there is a division into a semantic structure (What do I actually want to do?) And the motor composition of the action. For example, the semantic structure can be a desire to swim, and the motor composition can be a way to fulfill this plan, i.e. certain swimming style: crawl or breaststroke. Keep in mind that you don't know how to swim yet, and therefore you watch experienced swimmers, choosing the most suitable style for yourself.

At the second stage, sensory corrections are identified and painted. The difference between determining the motor composition and “probing” sensory corrections is that at the first stage the student establishes how the movements that make up the skill look like from the position of the observer, and at the second stage he tries to feel these movements from the inside. At this stage it is necessary maximum amount repetitions, each of which, as noted above, will not be a mechanical resumption of movement, but its modification. Work with the skill here is on a conscious level. A person tries to understand the movement (How do they do it?) and pick up ready-made motor automatisms from his personal repertoire of movements or create new ones. When such automatisms are found, a seemingly miraculous leap in skill development occurs. "The secret of mastering the movement lies not in some special body movements, but in a special kind of sensations. They cannot be shown, but can only be experienced" (N. A. Bernshtein).

In connection with the second stage of skill formation, the problem of skill transfer. In the tradition of behaviorism, there is still a theory "identical components". According to this theory, it is precisely the sequence of reactions that is developed, which can then be transferred from one activity to another. Such a logic of reasoning leads us to the conclusion that, for example, the ability to saw wood should help to master the violin - the movements seem to be the same! However, each of us understands that this is not so. N. A. Bernshtein believed that the transfer of a skill is possible, but it should not be a transfer of movements, but a transfer of ready-made sensory corrections. So, for example, a person who knows how to ride a bicycle will learn to skate more easily. The fact is that both the first and second skills are based on a general sense of movement, namely, maintaining balance over a narrow support.

At the third stage of formation, background scan, those. motor skill automation. The sensory corrections formed at the previous stage leave consciousness and begin to be performed automatically. Gradually, more and more of the skill becomes almost independent of consciousness. After all, unlike a beginner swimmer, we don’t think how to swim, but “just” swim.

The task of the fourth stage is triggering background corrections. All components of the skill are integrated into a single whole.

The fifth stage is the stage skill standardization. The skill becomes stable, each new execution of it is more and more similar in appearance to the previous one (it is similar, since in fact there are variations every time).

And finally, the last, sixth, stage is the stage stabilization. The skill becomes resistant to interference, as if by itself. This stage is familiar to people who have recently got behind the wheel of a car. At first, they can only drive in complete silence, but gradually they learn to perform several actions at the same time, for example, not only follow the road, but also listen to the radio and even carry on a conversation.

According to Bernstein, each skill is a functional system to ensure the achievement of a certain goal and has a level structure, and, according to the author, "each level of movement construction is the key to solving a certain class of motor tasks." The most fundamental level of movement building is the level of tone (level A). At this level, coordination of the body as a whole occurs, until sufficiently independent movements of the limbs are isolated. The task of level A is the general balance of the body in the process of performing a movement. The source of sensory corrections for movements of this level is proprioceptive sensitivity. Above the level of tone, the level of muscular-articular linkages is built up (level B). At this level, movements can be realized that include the work of large muscle groups of the limbs or the face, but do not require coordination from the side of vision and hearing. In other words, the corrections for movement at this level come from the body (kinesthetic sensitivity). An example here is running in place or yawning. The next level is the level of space (level C). Here, the source of corrections is not the body itself, but the spatial field in which target displacement movements unfold, for example, taking an object or climbing stairs. Highest level movement construction according to Bernstein is the level of actions (level D). At level D, actions include complex sequences of individual movements that are united by the meaning of the problem being solved. It is at this level that the articulation of speech takes place. The source of corrections for the unfolding of a semantic chain action is the conscious idea of ​​the action plan, i.e. level D is available only to humans.

Although Bernstein himself developed his theory in relation to the development of motor skills, the patterns he discovered turned out to be so fundamental that they can be extended to cognitive skills (for example, the skills of generating syntactic constructions).

The advantage of the concept of N. A. Bernstein over all the interpretations of learning described above is that here the skill is presented as a hierarchically organized system that includes observation, insight, and the development of reactions. Only taken together all the "elements" of learning lead to the successful mastering of the skill.

Thus, it is possible to distinguish various stages in the evolution of the psyche, associated primarily with the complication of living conditions and the activity of organisms (Table 3.1). Adaptation to changing conditions includes the aspect of the lifetime formation of new ways of behavior - learning. The higher the level of mental organization of the body, the more diverse and systemic processes of learning it is included.

Table 3.1

Stages of development of the psyche and their features

Stage of development of the psyche	Reflected aspects of reality	Forms of learning	Activity structure
prepsychic stage	Physical influences	No learning	No activity
Elementary sensory psyche	Individual object properties	Conditioned reflex	Single phase activity
Perceptual psyche	Whole objects	operant learning	Selection of operations
Intelligence	situations	Imitation Insight	The transfer of operations from one activity to another, the formation of preverbal generalizations
Consciousness	Objective stable properties of reality outside their connection with the subjective state	Vicarious learning Learning through reasoning	Allocation of actions in the structure of activities, Symbolic activity, Speech

Introduction………………………………………………………………..2

1. Psychophysiological basis for the organization of movements……...3

1.1. The principle of sensory corrections…………………………….4

1.2. Scheme of the reflex ring………………………………6

1.3. Movement levels……………………………..7

2. Formation of motor skills……………………….10

2.1. The structure of motor skills ………...……………10

2.2. The nature of skill and training. ………………………….12

H. Level approach in the analysis of the mechanisms of mental activity………………………………………………………..…..15

15

3.2. Perception…………………..…………………………………20

Conclusion…………………………………………………………..26

References……………………………………………………27

Introduction.

The concept of the physiology of movements that currently exists in psychology was formulated and experimentally substantiated by the outstanding Russian scientist N. A. Bernshtein.

A neuropathologist by education, a physiologist by his scientific interests, N. A. Bernshtein spoke in scientific literature as a passionate defender of the principle of activity - one of those principles on which the psychological theory activities. In 1947, one of Bernstein's main books "On the Construction of Movements" was published, which was awarded the State Prize. In this book, a number of completely new ideas were expressed. One of them consisted in refuting the principle of the reflex arc as a mechanism for organizing movements and replacing it with the principle of the reflex ring.

The purpose of this work is to analyze the main aspects of the theory of construction of movements by N. A. Bershtein.

The object of study is the patterns of organization of movement.

Work tasks:

1) Describe the psychophysiological basis of the organization of movements;

2) Consider the mechanisms of skills formation;

3) Identify the main mechanisms of mental activity, such as: attention and perception.

1. Psychophysiological basis for the organization of movements.

In the works of N. A. Bernshtein, the problem of the mechanisms of organization of human movements and actions was brilliantly developed. Dealing with this problem, N. A. Bernshtein revealed himself as a very psychologically thinking physiologist, as a result, his theory and the mechanisms he identified turned out to be organically combined with the theory of activity; they allowed us to deepen our understanding of the operational and technical aspects of the activity.

N. A. Bernstein appeared in the scientific literature as a passionate defender of the principle of activity - one of those principles on which the psychological theory of activity rests.

In 1947, one of the main books of N. A. Bernshtein "On the Construction of the Movement" was published, which was awarded the State Prize. This book reflects the results of almost thirty years of work of the author and his collaborators in the field of experimental, clinical and theoretical research movements and expressed a number of completely new ideas.

One of them consisted in refuting the principle of the reflex arc as a mechanism for organizing movements and replacing it with the principle of the reflex ring. This point of the H.A. Bernstein contained, thus, criticism of the higher nervous activity points of view on the mechanism of the conditioned reflex as on the universal principle of the analysis of higher nervous activity.

The object of study N. A. Bernshtein made the natural movements of a normal, intact organism, and, basically, the movements of a person. Thus, the contingent of movements in which he was engaged was immediately determined; these were labor, sports, household movements, etc. Of course, it took development special methods registration of movements, which was successfully carried out by Bernstein.

Before the works of N. A. Bernstein, there was an opinion in physiology (which was also stated in textbooks) that a motor act is organized as follows: at the stage of learning to move in the motor centers, its program is formed and fixed; then, as a result of the action of some stimulus, it is excited, motor command impulses go to the muscles, and the movement is realized. Thus, in the most general form, the movement mechanism was described by a reflex arc diagram: stimulus - the process of its central processing (excitation of programs) - motor reaction.

The first conclusion reached by N. A. Bernshtein was that any complex movement could not be carried out in this way. Generally speaking, a very simple movement, such as a knee jerk or pulling the hand away from the fire, can result from the direct conduction of motor commands from the center to the periphery. But complex motor acts, which are designed to solve some problem, achieve some result, cannot be built like that. The main reason is that the result of any complex movement depends not only on the actual control signals, but also on a number of additional factors.

General properties: they all introduce deviations in the planned course of movement, but they themselves are not amenable to preliminary accounting. As a result, the ultimate goal of a movement can only be achieved if it is continuously amended or corrected. And for this, the central nervous system must know what the real fate of the current movement is. In other words, the CNS must continuously receive afferent signals containing information about the actual course of movement, and then be processed into correction signals.

1.1. The principle of sensory corrections.

N. A. Bernshtein proposed a completely new principle of motion control, which was called the principle of sensory corrections. Consider the factors that, according to Bernstein, influence the progress of the movement.

First, this reactive forces. And he considered an example: for example, if a person waves his hand strongly, then in other parts of the body he will develop reactive forces that will change their position and tone.

Secondly, this inertial forces. If a person abruptly raises his hand, then it flies up not only due to those motor impulses that are sent to the muscles, but from a certain moment it moves by inertia, that is, certain inertial forces arise. N. A. Bernshtein believed that the phenomenon of inertia is present in any movement.

Thirdly, this external forces, which affect the progress of the movement. Example: if the movement is directed to any object, then it meets resistance from its side. And this resistance is most often unpredictable.

The fourth factor, according to N. A. Bernshtein: there is another factor that is not always taken into account when starting to perform movements - this is initial state of the muscles. The state of the muscle changes when performing a movement along with a change in its length, as well as as a result of fatigue and other reasons. Therefore, the same motor impulse, reaching the muscle, can give a completely different result.

There is a whole list of factors that have a direct impact on the progress of the movement. Central nervous system, according to Bernstein, constant information about the progress of the movement is necessary. This information is called feedback signals. These signals can simultaneously come from the muscles to the brain through several channels. He gives an example: when we move, information about the position of individual parts of the body comes from proprioceptive receptors. However, in parallel, information enters through the organs of vision. A similar picture is observed even when performing speech movements. A person receives information not only from the receptors that control the movements of the language apparatus, but also through hearing. Moreover, the information coming through different channels must be consistent, otherwise the execution of the movement becomes impossible.

1.2 Scheme of the reflex ring.

There is a certain scheme for the implementation of movement mechanisms. It was called the reflex ring diagram by Bernstein. This scheme is based on the principle of sensory corrections and is its further development.

In a simplified form, this scheme looks like this: effector commands come from the motor center (M) to the muscle (working point of the muscle). From the working point of the muscle, afferent feedback signals go to the sensory center. In the central nervous system, the information received is processed, i.e., it is recoded into motor correction signals, after which the signals again enter the muscle. It turns out a ring process of control.

The fundamental difference between the concepts of building movements based on the reflex arc and the reflex ring.

In this scheme, the reflex arc looks like one of its special cases, when movements are made that do not need correction, that is, movements of a reflex nature. Bernstein later detailed the scheme of the reflex ring. The circuit contains the following elements: motor "outputs" (effector), sensory "inputs" (receptor), working point or object (if we are talking about objective activity), decoding block, program, controller, setting device, comparison device.

With the presence more elements of the reflex ring functions in this way: the program contains the successive stages of a complex movement. At each specific moment, some particular stage or element is being worked out, the corresponding particular program is launched into the master device. Signals (SW - “what should be”) are sent from the master device to the comparison device. Feedback signals (IW - “what is”) come to the same block from the receptor, reporting on the state of the operating point. In the comparison device, these signals are compared, and at the output of it, mismatch signals (B\U) are obtained between the required and actual state of affairs. Then they get to the recoding block, from where correction signals come out, which through intermediate instances (regulator) get to the effector.