THEORETICAL FOUNDATIONS OF AGE PHYSIOLOGY (DEVELOPMENTAL PHYSIOLOGY) OF A CHILD
The systemic principle of the organization of physiological functions in ontogenesis
The importance of identifying the patterns of development of the child's body and the features of the functioning of its physiological systems at different stages of ontogenesis for health protection and the development of age-appropriate pedagogical technologies determined the search for optimal ways to study the physiology of the child and those mechanisms that provide adaptive adaptive nature of development at each stage of ontogenesis.
According to modern ideas, which were initiated by the works of A.N. Severtsov in 1939, all functions are formed and undergo changes in the close interaction of the organism and the environment. In accordance with this idea, the adaptive nature of the functioning of the body in different age periods is determined by two the most important factors: morphological and functional maturity of physiological systems and the adequacy of the influencing environmental factors to the functional capabilities of the body.
Traditional for Russian physiology (I.M. Sechenov, I.P. Pavlov, A.A. Ukhtomsky, N.A. Bernstein. P.K. Anokhin and others) is the systemic principle of organizing an adaptive response to environmental factors. This principle, considered as the basic mechanism of the organism's life, implies that all types of adaptive activity of physiological systems and the whole organism are carried out through hierarchically organized dynamic associations, including individual elements of one or different organs (physiological systems).
A.A. Ukhtomsky, who put forward the principle of the dominant as a functional working organ that determines the adequate response of the body to external influences. Dominant, according to A.A. Ukhtomsky, is a constellation of nerve centers united by the unity of action, the elements of which can be topographically sufficiently distant from each other and at the same time tuned to a single rhythm of work. Concerning the mechanism underlying the dominant, A.A. Ukhtomsky drew attention to the fact that normal activity relies "not on once and for all a certain and staged functional statics of various foci as carriers of individual functions, but on the incessant intercentral dynamics of excitations at different levels: cortical, subcortical, medullary, spinal." This emphasized the plasticity, the importance of the spatio-temporal factor in the organization of functional associations that ensure the adaptive reactions of the organism. Ideas A.A. Ukhtomsky about functional-plastic systems for organizing activities were developed in the works of N.A. Bernstein. Studying the physiology of movements and the mechanisms of the formation of a motor skill, N.A. Bernstein paid attention not only to the coordinated work of nerve centers, but also to phenomena occurring on the periphery of the body - at working points. As early as 1935, this allowed him to formulate the position that the adaptive effect of an action can be achieved only if there is an end result in the central nervous system in some coded form - a “model of the required future”. In the process of sensory correction, by means of feedback coming from working organs, it is possible to compare information about activities already carried out with this model.
Expressed by N.A. Bernstein, the position on the importance of feedback in achieving adaptive reactions was of paramount importance in understanding the mechanisms of regulation of the adaptive functioning of the organism and the organization of behavior.
The classical idea of an open reflex arc has given way to the idea of closed circuit regulation. A very important provision developed by N.A. Bernstein, is the high plasticity of the system established by him - the possibility of achieving the same result in accordance with the "model of the required future" with an ambiguous way to achieve this result, depending on specific conditions.
Developing the idea of a functional system as an association that provides the organization of an adaptive response, P.K. Anokhin, as a system-forming factor that creates a certain ordered interaction of individual elements of the system, considered the useful result of the action. “It is the useful result that constitutes the operational factor that contributes to the fact that the system ... can completely reorganize the arrangement of its parts in space and time, which provides the adaptive result necessary in this situation” (Anokhin).
Of paramount importance for understanding the mechanisms that ensure the interaction of individual elements of the system is the position developed by N.P. Bekhtereva and her collaborators, about the presence of two systems of connections: rigid (innate) and flexible, plastic. The latter are most important for organizing dynamic functional associations and providing specific adaptive reactions in real conditions of activity.
One of the main characteristics of the systemic support of adaptive responses is the hierarchical nature of their organization (Wiener). Hierarchy combines the principle of autonomy with the principle of subordination. Along with flexibility and reliability, hierarchically organized systems are characterized by high energy structural and information efficiency. Separate levels may consist of blocks that perform simple specialized operations and transmit processed information to higher levels of the system, which perform more complex operations and at the same time exert a regulatory influence on lower levels.
The hierarchy of the organization, based on the close interaction of elements both at the same level and at different levels of systems, determines the high stability and dynamism of the ongoing processes.
In the course of evolution, the formation of hierarchically organized systems in ontogeny is associated with progressive complication and layering of regulation levels on top of each other that ensure the improvement of adaptive processes (Vasilevsky). It can be assumed that the same regularities take place in ontogeny.
The importance of a systematic approach to the study of the functional properties of a developing organism, its ability to form an optimal adaptive response for each age, self-regulation, the ability to actively seek information, develop plans and programs of activity is obvious.
Regularities of ontogenetic development. The concept of age norm
Of paramount importance for understanding how functional systems are formed and organized in the process of individual development is formulated by A.N. Severtsov, the principle of heterochrony in the development of organs and systems, developed in detail by P.K. Anokhin in the theory of systemogenesis. This theory is based on experimental studies early ontogenesis, which revealed the gradual and uneven maturation of individual elements of each structure or organ, which are consolidated with elements of other organs involved in the implementation of this function, and, integrating into a single functional system, implement the principle of "minimum support" of an integral function. Different functional systems, depending on their importance in providing vital functions, mature at different periods of postnatal life - this is developmental heterochrony. It provides a high adaptability of the organism at each stage of ontogenesis, reflecting the reliability of the functioning of biological systems. The reliability of the functioning of biological systems, according to the concept of A.A. Markosyan, is one of general principles individual development. It is based on such properties of a living system as the redundancy of its elements, their duplication and interchangeability, the speed of return to relative constancy and the dynamism of individual parts of the system. Studies have shown (Farber) that in the course of ontogenesis the reliability of biological systems goes through certain stages of formation and formation. And if in the early stages of postnatal life it is provided by a rigid, genetically determined interaction of individual elements of the functional system, which ensures the implementation of elementary reactions to external stimuli and the necessary vital functions (for example, sucking), then in the course of development, plastic connections that create conditions for a dynamic electoral organization of the components of the system. On the example of the formation of the information perception system, a general pattern was established for ensuring the reliability of the adaptive functioning of the system. Three functionally different stages of its organization have been identified: Stage 1 (the neonatal period) - the functioning of the earliest maturing block of the system, which provides the ability to respond according to the "stimulus - reaction" principle; 2nd stage (first years of life) - generalized same-type involvement of elements of a higher level of the system, the reliability of the system is ensured by duplication of its elements; Stage 3 (observed from preschool age) - a hierarchically organized multi-level regulation system provides the possibility of specialized involvement of elements of different levels in information processing and organization of activities. In the course of ontogenesis, as the central mechanisms of regulation and control improve, the plasticity of the dynamic interaction of the elements of the system increases; selective functional constellations are formed in accordance with the specific situation and the task (Farber, Dubrovinskaya). This leads to the improvement of the adaptive reactions of the developing organism in the process of complicating its contacts with the external environment and the adaptive nature of functioning at each stage of ontogenesis.
It can be seen from the above that individual stages of development are characterized both by the features of the morphological and functional maturity of individual organs and systems, and by the difference in the mechanisms that determine the specifics of the interaction of the organism and the external environment.
The need for a specific description of the individual stages of development, taking into account both of these factors, raises the question of what should be considered as the age norm for each of the stages.
For a long time, the age norm was considered as a set of average statistical parameters characterizing the morphological and functional characteristics of the organism. This idea of the norm has its roots in those times when practical needs determined the need to highlight some average standards that make it possible to identify developmental deviations. Undoubtedly, at a certain stage in the development of biology and medicine, such an approach played a progressive role, making it possible to determine the average statistical parameters of the morphological and functional characteristics of a developing organism; and at present it allows solving a series practical tasks(for example, when calculating the standards of physical development, normalizing the impact of environmental factors, etc.). However, such an idea of the age norm, which absolutizes the quantitative assessment of the morphological and functional maturity of the organism at different stages of ontogenesis, does not reflect the essence of age-related transformations that determine the adaptive direction of the development of the organism and its relationship with the external environment. It is quite obvious that if the qualitative specificity of the functioning of physiological systems at individual stages of development remains unaccounted for, then the concept of the age norm loses its content, it ceases to reflect the real functional capabilities of the organism in certain age periods.
The idea of the adaptive nature of individual development has led to the need to revise the concept of the age norm as a set of average statistical morphological and physiological parameters. A position was put forward according to which the age norm should be considered as a biological optimum for the functioning of a living system, providing an adaptive response to environmental factors (Kozlov, Farber).
Age periodization
Differences in the idea of the criteria for the age norm are also determined by approaches to periodization. age development. One of the most common is the approach, which is based on the analysis of the assessment of morphological features (growth, change of teeth, weight gain, etc.). The most complete age periodization based on morphological and anthropological features was proposed by V.V. Bunak, according to whom changes in body size and related structural and functional features reflect the transformation of the body's metabolism with age. According to this periodization, the following periods are distinguished in postnatal ontogenesis: infant, covering the first year of a child's life and including the initial (1–3, 4–6 months), middle (7–9 months), and final (10–12 months) cycles; first childhood (initial cycle 1-4 years, final - 5-7 years); second childhood (initial cycle: 8-10 years old - boys, 8-9 years old - girls; final: 11-13 years old - boys, 10-12 years old - girls); teenage (14–17 years old - boys, 13–16 years old - girls); youth (18–21 years old - boys, 17–20 years old - girls); from 21–22 years old, the adult period begins. This periodization is close to that adopted in pediatric practice (Tour, Maslov); along with morphological factors, it also takes into account social ones. Infancy, according to this periodization, corresponds to younger toddler or infancy; the period of the first childhood combines senior toddler or pre-preschool age and preschool; the period of the second childhood corresponds to the primary school age and adolescence to the senior preschool age. However, this classification of age periods, reflecting existing system upbringing and education cannot be considered acceptable, since, as you know, the issue of the beginning of systematic education has not yet been resolved; boundary between preschool and school age requires clarification, the concepts of primary and secondary school age are rather amorphous.
According to the age periodization adopted at a special symposium in 1965, the following periods are distinguished in the human life cycle until reaching adulthood: newborn (1-10 days); infancy (10 days - 1 year); early childhood (1–3 years); first childhood (4–7 years); second childhood (8-12 years old - boys, 8-11 years old - girls); adolescence (13–16 years old - boys, 12–15 years old - girls) and adolescence (17–21 years old - boys, 16–20 years old - girls) (The problem of human age periodization). This periodization is somewhat different from that proposed by V.V. Bunak by highlighting the period of early childhood, some displacement of the boundaries of the second childhood and adolescence. However, the problem of age periodization has not been finally resolved, primarily because all existing periodizations, including the latest generally accepted one, are not physiologically substantiated enough. They do not take into account the adaptive nature of development and the mechanisms that ensure the reliability of the functioning of physiological systems and the whole organism at each stage of ontogenesis. This determines the need to select the most informative criteria for age periodization.
In the process of individual development, the child's body changes as a whole. Its structural, functional and adaptive features are due to the interaction of all organs and systems at different levels of integration - from intracellular to intersystem. In accordance with this, the key task of age periodization is the need to take into account the specific features of the functioning of the whole organism.
One of the attempts to search for an integral criterion characterizing the vital activity of an organism was the assessment of the energy capabilities of the organism proposed by Rubner, the so-called “energy surface rule”, which reflects the relationship between the level of metabolism and energy and the size of the body surface. This indicator, which characterizes the energy capabilities of the body, reflects the activity of physiological systems associated with metabolism: blood circulation, respiration, digestion, excretion and the endocrine system. It was assumed that the ontogenetic features of the functioning of these systems should obey the "energetic rule of the surface."
However, the above theoretical propositions on the adaptive adaptive nature of development give reason to believe that age periodization should be based not so much on criteria that reflect the stationary features of the organism’s vital activity already achieved by a certain moment of maturation, but on criteria for the interaction of the organism with the environment.
The need for such an approach to the search for physiological criteria for age periodization was also expressed by I.A. Arshavsky. According to his view, age periodization should be based on criteria that reflect the specifics of the integral functioning of the organism. As such a criterion, the leading function allocated for each stage of development is proposed.
In the detailed study by I.A. Arshavsky and his colleagues in early childhood, in accordance with the nature of nutrition and the characteristics of motor acts, identified periods: neonatal, during which feeding with colostrum milk (8 days), lactotrophic form of nutrition (5–6 months), lactotrophic form of nutrition with complementary foods and the appearance of a standing posture (7-12 months), toddler age (1-3 years) - the development of locomotor acts in the environment (walking, running). It should be noted that I. A. Arshavsky attached special importance to motor activity as the leading factor in development. Criticizing the "energetic rule of the surface", I.A. Arshavsky formulated the concept of the "energy rule of skeletal muscles", according to which the intensity of the body's vital activity, even at the level of individual tissues and organs, is determined by the characteristics of the functioning of skeletal muscles, providing at each stage of development the features of the interaction of the organism and the environment.
However, it must be borne in mind that in the process of ontogenesis, the active attitude of the child to environmental factors increases, the role of higher departments The central nervous system in providing adaptive reactions to environmental factors, including those reactions that are realized through motor activity.
Therefore, a special role in age periodization is acquired by criteria that reflect the level of development and qualitative changes in adaptive mechanisms associated with the maturation of various parts of the brain, including the regulatory structures of the central nervous system that determine the activity of all physiological systems and the behavior of the child.
This brings together the physiological and psychological approaches to the problem of age periodization and creates the basis for the development of a unified concept of periodization of the child's development. L.S. Vygotsky considered mental neoplasms characteristic of specific stages of development as criteria for age periodization. Continuing this line, A.N. Leontiev and D.B. Elkonin attached special importance in age periodization to the "leading activity" that determines the emergence of mental neoplasms. At the same time, it was noted that the features of the mental, as well as the features physiological development are determined by both internal (morphofunctional) factors and external conditions of individual development.
One of the goals of age periodization is to establish the boundaries of individual stages of development in accordance with the physiological norms of the response of a growing organism to the influence of environmental factors. The nature of the body's responses to the impacts exerted directly depends on the age-related features of the functioning of various physiological systems. According to S.M. Grombach, when developing the problem of age periodization, it is necessary to take into account the degree of maturity and functional readiness of various organs and systems. If certain physiological systems are not leading at a certain stage of development, they can ensure the optimal functioning of the leading system in various environmental conditions, and therefore the level of maturity of these physiological systems cannot but affect the functional capabilities of the whole organism as a whole.
To judge which system is leading for a given stage of development and where lies the boundary of changing one leading system to another, it is necessary to assess the level of maturity and features of the functioning of various organs and physiological systems.
Thus, age periodization should be based on three levels of studying the physiology of the child:
1 - intrasystem;
2 - intersystem;
3 - a holistic organism in interaction with the environment.
The question of periodization of development is inextricably linked with the choice of informative criteria that should form its basis. This brings us back to the age norm. One can fully agree with the statement of P.N. Vasilevsky that "the optimal modes of activity of the functional systems of the body are not average values, but by continuous dynamic processes occurring in time in a complex network of co-adapted regulatory mechanisms. There is every reason to believe that the most informative are the criteria for age-related transformations that characterize the state of physiological systems in conditions of activity that is as close as possible to the one that the object of study - the child - encounters in his daily life, i.e. indicators that reflect real adaptability to conditions environment and adequacy of response to external influences.
Based on the concept of the systemic organization of adaptive reactions, it can be assumed that such indicators should primarily be considered those that reflect not so much the maturity of individual structures as the possibility and specifics of their interaction with the environment. This applies to indicators that characterize age features each physiological system individually, and to indicators of the integral functioning of the organism. All of the above requires an integrated approach to the analysis of age-related transformations at the intrasystem and intersystem levels.
No less important in developing the problems of age periodization is the question of the boundaries of functionally different stages. In other words, physiologically substantiated periodization should be based on the identification of stages of the "actual" physiological age.
Isolation of functionally different stages of development is possible only if there is data on the features of the adaptive functioning of various physiological systems within each year of a child's life.
Long-term research carried out at the Institute age physiology RAO made it possible to establish that, despite the heterochrony of the development of organs and systems, within the periods considered as unified, key points were identified, which are characterized by significant qualitative morphofunctional transformations leading to adaptive rearrangements of the body. IN preschool age this is the age from 3-4 to 5-6 years, in primary school - from 7-8 to 9-10 years. In adolescence, qualitative changes in the activity of physiological systems are confined not to a certain passport age, but to the degree of biological maturity (certain stages of puberty - stages II–III).
Sensitive and critical periods of development
The adaptive nature of the development of the organism determines the need to take into account in age periodization not only the features of the morphofunctional development of the physiological systems of the body, but also their specific sensitivity to various external influences. Physiological and psychological studies have shown that sensitivity to external influences is selective at different stages of ontogenesis. This formed the basis for the concept of sensitive periods as periods of greatest sensitivity to environmental factors.
Revealing and taking into account sensitive periods of development of body functions is an indispensable condition for creating favorable adequate conditions for effective learning and maintaining the health of the child. The high susceptibility of certain functions to the influence of environmental factors should, on the one hand, be used for an effective targeted impact on these functions, contributing to their progressive development, and on the other hand, the influence of negative external environmental factors should be controlled, because it can lead to a violation of the development of the organism.
It should be emphasized that ontogenetic development combines periods of evolutionary (gradual) morphofunctional maturation and periods of revolutionary, turning points in development, which can be associated with both internal (biological) and external (social) factors of development.
An important and requiring special attention is the question of critical periods of development . IN evolutionary biology It is customary to consider the critical period the stage of early postnatal development, characterized by the intensity of morphofunctional maturation, when, due to the absence of environmental influences, the function may not be formed. For example, in the absence of certain visual stimuli in early ontogenesis, their perception is not formed in the future, the same applies to the speech function.
In the process of further development, critical periods may arise as a result of a sharp change in social and environmental factors and their interaction with the process of internal morphofunctional development. Such a period is the age of the beginning of learning, when qualitative changes in the morphofunctional maturation of basic brain processes occur during a period of a sharp change in social conditions.
puberty- the beginning of puberty - is characterized by a sharp increase in the activity of the central link of the endocrine system (hypothalamus), which leads to a sharp change in the interaction of subcortical structures and the cerebral cortex, resulting in a significant decrease in the effectiveness of central regulatory mechanisms, including those determining voluntary regulation and self-regulation. In addition, social requirements for adolescents increase, their self-esteem increases. This leads to a discrepancy between socio-psychological factors and the functional capabilities of the body, which may result in deviations in health and behavioral maladaptation.
Thus, it can be assumed that the critical periods of development are due both to the intensive morphological and functional transformation of the main physiological systems and the whole organism, and the specifics of the increasingly complex interaction of internal (biological) and socio-psychological factors of development.
When considering the issues of age periodization, it must be borne in mind that the boundaries of the stages of development are very arbitrary. They depend on specific ethnic, climatic, social and other factors. In addition, the “actual” physiological age often does not coincide with the calendar (passport) age due to differences in the rate of maturation and conditions for the development of organisms. different people. It follows that when studying the functional and adaptive capabilities of children of different ages, it is necessary to pay attention to the assessment of individual indicators of maturity. Only with a combination of age and individual approach To study the characteristics of the functioning of the child, it is possible to develop adequate hygienic and pedagogical measures that ensure the preservation of health and the progressive development of the body and personality of the child.
Questions and tasks
1. Tell us about the systemic principle of organizing an adaptive response.
2. What are the patterns of ontogenetic development? What is the age limit?
3. What is age periodization?
4. Tell us about the sensitive and critical periods of development.
Chapter 3
Before proceeding to the study of the most important regularities of the age development of an organism, it is necessary to understand what an organism is, what principles are laid down by Nature in its general design and how it interacts with the outside world.
Almost 300 years ago, it was proved that all living things consist of cells. The human body consists of several billion tiny cells. These cells are far from identical in appearance, in their properties and functions. Cells that are similar to each other combine to form fabrics. There are many types of tissue in the body, but they all belong to only 4 types: epithelial, connective, muscle and nervous. epithelial tissues form the skin and mucous membranes, many internal organs - the liver, spleen, etc. In epithelial tissues, the cells are located closely to each other. Connective tissue has very large intercellular spaces. This is how bones, cartilage are arranged, blood is also arranged - all these are varieties of connective tissue. muscular And nervous tissues are excitable: they are able to perceive and conduct an impulse of excitation. At the same time, for nervous tissue this is the main function, while muscle cells can still contract, significantly changing in size. This mechanical work can be transferred to the bones or fluids inside the muscle sacs.
Fabrics in various combinations form anatomical organs. Each organ consists of several tissues, and almost always, along with the main, functional tissue that determines the specifics of the organ, there are elements of nervous tissue, epithelium and connective tissue. Muscle tissue may not be present in the organ (for example, in the kidneys, spleen, etc.).
Anatomical organs are folded into anatomical and physiological systems, which are united by the unity of the main function they perform. This is how the musculoskeletal, nervous, integumentary, excretory, digestive, respiratory, cardiovascular, reproductive, endocrine systems and blood are formed. All these systems together make up organism person.
The elementary unit of life is the cell. The genetic apparatus is concentrated in the cell core, i.e., localized and protected from the unexpected effects of a potentially aggressive environment. Each cell is isolated from the rest of the world due to the presence of a complexly organized shell - membranes. This shell consists of three layers of chemically and functionally different molecules, which, acting in concert, ensure the performance of many functions: protective, contact, sensitive, absorbing and releasing. The main job of the cell membrane is to organize the flow of matter from the environment into the cell, and from the cell to the outside. cell membrane- the basis of all vital activity of the cell, which dies when the membrane is destroyed. Any cell needs food and energy for its life activity - after all, the functioning of the cell membrane is also largely associated with the expenditure of energy. To organize the energy flow through the cell, there are special organelles in it that are responsible for generating energy - mitochondria. It is believed that billions of years ago, mitochondria were independent living organisms that learned in the course of evolution to use some chemical processes to generate energy. Then they entered into symbiosis with other unicellular organisms, which, thanks to this cohabitation, received a reliable source of energy, and the ancestors of mitochondria - reliable protection and a guarantee of reproduction.
The building function in the cell is performed ribosomes- factories for the production of proteins based on templates copied from the genetic material stored in the nucleus. Acting through chemical stimuli, the nucleus governs all aspects of cell life. The transmission of information inside the cell is carried out due to the fact that it is filled with a jelly-like mass - cytoplasm, in which many biochemical reactions take place, and substances of informational value can easily penetrate into the farthest corners of the intracellular space due to diffusion.
Many cells have, in addition, one or another adaptation for movement in the surrounding space. It could be flagellum(like a spermatozoon) villi(as in the intestinal epithelium) or the ability to transfuse the cytoplasm in the form pseudopodium(as in lymphocytes).
Thus, the most important structural elements of a cell are its shell (membrane), control organ (nucleus), energy supply system (mitochondrion), building block (ribosome), mover (cilia, pseudopodia, or flagellum) and internal environment (cytoplasm). Some unicellular organisms they also have an impressive calcified skeleton that protects them from enemies and accidents.
Surprisingly, the human body, which consists of many billions of cells, has, in fact, the same major building blocks. Man is separated from the environment by his skin membrane. It has a mover (muscles), a skeleton, organs of control (the brain and spinal cord and endocrine system), an energy supply system (respiration and blood circulation), a primary food processing unit (gastrointestinal tract), and an internal environment (blood, lymph, interstitial fluid). This scheme does not exhaust all the structural components of the human body, but allows us to conclude that any living being is built according to a fundamentally unified plan.
Of course, a multicellular organism has a number of features and, apparently, advantages - otherwise the process of evolution would not have been directed towards the emergence of multicellular organisms and the world would still be inhabited exclusively by those whom we call "simple".
Main constructive difference between a unicellular and a multicellular organism lies in the fact that the organs of a multicellular organism are built from millions of individual cells, which, according to the principle of similarity and functional affinity, are combined into tissues, while the organelles of a unicellular organism are elements of a single cell.
What is the real advantage of a multicellular organism? In the ability to separate functions in space and time, as well as in the specialization of individual tissue and cellular structures to perform strictly defined functions. In fact, these differences are similar to the difference between the medieval subsistence economy and modern industrial production. The cell, which is an independent organism, is forced to solve all the problems that confront it, using the resources it has. A multicellular organism singles out for the solution of each of the functional tasks a special population of cells or a complex of such populations (tissue, organ, functional system) that are maximally adapted for solving this particular task. It is clear that the efficiency of problem solving by a multicellular organism is much higher. More precisely, a multicellular organism is much more likely to adapt to the wide range of situations it has to face. This implies a fundamental difference between a cell and a multicellular organism in the adaptation strategy: the first reacts holistically and in a generalized way to any environmental influence, the second is able to adapt to living conditions due to the restructuring of the functions of only some of its constituent parts - tissues and organs.
It is important to emphasize that the tissues of a multicellular organism are very diverse and each the best way adapted to perform a small number of functions necessary for the life and adaptation of the whole organism. At the same time, the cells of each of the tissues are able to perfectly perform only one single function, and the entire diversity of the functional capabilities of the body is provided by the diversity of its constituent cells. For example, nerve cells are only able to produce and conduct an impulse of excitation, but they are not able to change their size or carry out the destruction of toxic substances. Muscle cells are able to conduct an impulse of excitation in the same way as nerve cells, but at the same time they themselves contract, ensuring the movement of body parts in space or changing the tension (tone) of the structures consisting of these cells. Liver cells are not able to conduct electrical impulses or contract - but their biochemical power ensures the neutralization of a huge number of harmful and toxic molecules that enter the bloodstream during the life of the body. Bone marrow cells are specially designed for the production of blood and cannot be occupied with anything else. Such a "division of labor" is a characteristic property of any complexly organized system; social structures also function according to the same rules. This must be taken into account when predicting the results of any reorganizations: no specialized subsystem is able to change the nature of its functioning if its own structure does not change.
The emergence of tissues with qualitative characteristics in the process of ontogenesis is a relatively slow process, and it does not occur due to the fact that existing cells acquire new functions: almost always, new functions are provided by new generations of cellular structures that are formed under the control of the genetic apparatus and under the influence of external requirements. or internal environment.
Ontogeny is a striking phenomenon, during which a unicellular organism (zygote) turns into a multicellular organism, maintaining integrity and viability at all stages of this remarkable transformation and gradually increasing the diversity and reliability of the functions performed.
Structural-functional and systemic approaches to the study of the body
Scientific physiology was born on the same day as anatomy - this happened in the middle of the 17th century, when the great English physician William Harvey received the permission of the church and the king and performed the first autopsy of a criminal sentenced to death after a thousand-year break in order to scientifically study the internal structure of the human body. Of course, even the ancient Egyptian priests, when embalming the bodies of their pharaohs, knew perfectly well the structure of the human body from the inside - but this knowledge was not scientific, it was empirical, and, moreover, secret: divulging any information about this was considered sacrilege and was punishable by death. The great Aristotle, teacher and mentor of Alexander the Great, who lived 3 centuries BC, had a very vague idea of how the body works and how it works, although he was encyclopedically educated and seemed to know everything that European civilization had accumulated by that time. More knowledgeable were the ancient Roman doctors - students and followers of Galen (II century AD), who laid the foundation for descriptive anatomy. Medieval Arab doctors gained great fame, but even the greatest of them - Ali Abu ibn Sina (in European transcription - Avicenna, XI century) - treated the human spirit rather than the body. And now W. Harvey, with a confluence of a huge number of people, conducts the first study in the history of European science of the structure of the human body. But Harvey was most interested in HOW the body WORKS. Since ancient times, people have known that a heart beats in the chest of each of us. Doctors at all times measured the pulse and assessed the state of health and the prospects for combating various diseases by its dynamics. Until now, one of the most important diagnostic techniques in the famous and mysterious Tibetan medicine is long-term continuous monitoring of the patient's pulse: the doctor sits at his bedside and keeps his finger on the pulse for hours, and then calls the diagnosis and prescribes treatment. It was well known to everyone: the heart stopped - life stopped. However, the Galen school, traditional at that time, did not connect the movement of blood through the vessels with the activity of the heart.
But before Harvey's eyes - a heart with tubes-vessels filled with blood. And Harvey understands that the heart is just a muscle bag that acts as a pump that pumps blood throughout the body, because vessels scatter throughout the body, which become more numerous and thinner as they move away from the pump. Through the same vessels, blood returns to the heart, making a complete revolution and continuously flowing to all organs, to every cell, carrying nutrients with it. Nothing is yet known about the role of oxygen, hemoglobin has not been discovered, doctors are in no way able to distinguish between proteins, fats and carbohydrates - in general, knowledge of chemistry and physics is still extremely primitive. But various technologies have already begun to develop, the engineering thought of mankind has invented many devices that facilitate production or create completely new, previously unprecedented technical possibilities. It becomes clear to Harvey's contemporaries that certain mechanisms , the structural basis of which is made up of separate organs, and each organ is designed to perform a particular function. The heart is a pump that pumps blood through the "veins", just like those pumps that supply water from lowland lakes to a manor on a hillock and feed fountains pleasing to the eye. Lungs are bellows through which air is pumped, as apprentices do in a forge, in order to heat iron more and make it easier to forge. Muscles are ropes attached to bones, and their tension causes these bones to move, which ensures the movement of the whole body, just as builders use hoists to lift huge stones to the upper floors of a temple under construction.
It is human nature to always compare new phenomena discovered by him with those already known, which have come into use. A person always builds analogies in order to make it easier to understand, to explain to himself the essence of what is happening. High level The development of mechanics in the era when Harvey was conducting his research inevitably led to a mechanical interpretation of the numerous discoveries made by physicians - Harvey's followers. Thus, structural-functional physiology was born with its slogan: one organ - one function.
However, with the accumulation of knowledge - and this largely depended on the development of the physical and chemical sciences, since it is they that supply the main methods for carrying out scientific research in physiology, it became clear that many organs perform not one, but several functions. Let's say the lungs - not only provide the exchange of gases between the blood and environment but are also involved in the regulation of body temperature. The skin, performing primarily the function of protection, is at the same time both an organ of thermoregulation and an organ of excretion. Muscles are able not only to actuate skeletal levers, but also, due to their contractions, to warm the blood flowing to them, maintaining temperature homeostasis. Examples of this kind can be given endlessly. The polyfunctionality of organs and physiological systems became especially clear in the late 19th and early 20th centuries. It is curious that at the same time, a wide variety of "universal" machines and tools appeared in technology, with a wide range of capabilities - sometimes, to the detriment of simplicity and reliability. This is an illustration of the fact that the technical thought of mankind and the level of scientific understanding of the organization of processes in wildlife develop in close interaction with each other.
By the middle of the 30s of the XX century. it became clear that even the concept of polyfunctionality of organs and systems is no longer able to explain the coherence of body functions in the process of adaptation to changing conditions or in the dynamics of age development. A new understanding of the meaning of the processes occurring in a living organism began to take shape, from which a systematic approach to the study of physiological processes was gradually formed. At the origins of this direction of physiological thought were outstanding Russian scientists - A.A. Ukhtomsky, N.A. Bernstein and P.K. Anokhin.
The most fundamental difference between the structural-functional and systemic approaches lies in the understanding of what is a physiological function. For structural-functional approach characteristic is the understanding of the physiological function as a certain process carried out by a certain (specific) set of organs and tissues, changing its activity in the course of functioning in accordance with the influence of control structures. In this interpretation, physiological mechanisms are those physical and chemical processes that underlie the physiological function and ensure the reliability of its implementation. The physiological process is the object that is in the center of attention of the structural-functional approach.
Systems approach is based on the idea of expediency, i.e., under a function in the framework of a systematic approach, they understand the process of achieving a certain goal, result. At various stages of this process, the need for the involvement of certain structures can change quite significantly, therefore the constellation (composition and nature of the interaction of elements) of a functional system is very mobile and corresponds to the particular task that is being solved at the current moment. The presence of a goal implies that there is some model of the state of the system before and after achieving this goal, an action program, and there is also a feedback mechanism that allows the system to control its current state (intermediate result) in comparison with the simulated one and, on this basis, make adjustments to the action program in order to achieve the end result.
From the standpoint of the structural-functional approach, the environment acts as a source of stimuli for certain physiological reactions. A stimulus has arisen - in response, a reaction has arisen, which either fades as you get used to the stimulus, or stops when the stimulus ceases to act. In this sense, the structural-functional approach considers the organism as a closed system that has only certain channels of information exchange with the environment.
The systems approach considers the body as open system, the objective function of which can be placed both inside and outside it. According to this view, the body responds to influences outside world as a whole, rebuilding the strategy and tactics of this response, depending on the results achieved, each time in such a way as to achieve either faster or more reliable model target results. From this point of view, the reaction to an external stimulus fades when the target function formed under its influence is realized. The stimulus may continue to act, or, on the contrary, it may cease to operate long before the completion of functional rearrangements, but once started, these rearrangements must go through the entire programmed path, and the reaction will end only when the feedback mechanisms bring information about the complete balance of the organism with the environment. at a new level of functional activity. A simple and clear illustration of this situation can serve as a reaction to any physical load: to perform it, muscle contractions are activated, which necessitates a corresponding activation of blood circulation and respiration, and even when the load has already been completed, the physiological functions still retain their increased activity for quite a long time, since they provide alignment of metabolic states and normalization of homeostatic parameters. The functional system that ensures the performance of physical exercise includes not only the muscles and nervous structures that give the order to the muscles to contract, but also the circulatory system, the respiratory system, the endocrine glands and many other tissues and organs involved in this process, associated with serious changes. the internal environment of the body.
The structural-functional view of the essence of physiological processes reflected a deterministic, mechanistic-materialistic approach, which was characteristic of all natural sciences 19th and early 20th centuries The pinnacle of its development can probably be considered the theory of conditioned reflexes by I.P. Pavlov, with the help of which the great Russian physiologist tried to understand the mechanisms of brain activity by the same methods by which he successfully studied the mechanisms of gastric secretion.
The systems approach stands on stochastic, probabilistic positions and does not reject teleological (expedient) approaches characteristic of the development of physics and other natural sciences in the second half of the 20th century. It has already been mentioned above that physiologists, together with mathematicians, within the framework of this approach, came to the formulation of the most general cybernetic laws that all living things obey. Equally important for understanding physiological processes at the present level are the ideas about the thermodynamics of open systems, the development of which is associated with the names of outstanding physicists of the 20th century. Ilya Prigogine, von Bertalanffy and others.
The body as a whole system
The modern understanding of complex self-organizing systems includes the idea that they clearly define the channels and methods of information transmission. In this sense, a living organism is a quite typical self-organizing system.
The body receives information about the state of the surrounding world and the internal environment with the help of sensors-receptors that use a wide variety of physical and chemical design principles. So, for a person, the most important is the visual information that we receive with the help of our opto-chemical sensors - the eyes, which are both a complex optical device with an original and accurate guidance system (adaptation and accommodation), as well as a physico-chemical converter of photon energy into electrical impulse of the optic nerves. Acoustic information comes to us through a bizarre and finely tuned auditory mechanism that converts the mechanical energy of air vibrations into electrical impulses of the auditory nerve. Temperature sensors are no less finely arranged, tactile (tactile), gravitational (sense of balance). Olfactory and gustatory receptors are considered to be the most evolutionarily ancient, having a huge selective sensitivity in relation to some molecules. All this information about the state of the external environment and its changes enters the central nervous system, which performs several roles simultaneously - a database and knowledge base, an expert system, a central processor, as well as the functions of operational and long-term memory. Information from receptors located inside our body also flows there and transmits information about the state of biochemical processes, about the tension in the work of certain physiological systems, about the actual needs of individual groups of cells and tissues of the body. In particular, there are sensors for pressure, carbon dioxide and oxygen content, acidity of various biological fluids, tension of individual muscles, and many others. Information from all these receptors is also sent to the center. Sorting of information coming from the periphery begins already at the stage of its reception - after all, the nerve endings of various receptors reach the central nervous system at its different levels, and, accordingly, information enters various parts of the central nervous system. However, all of it can be used in the decision-making process.
The decision must be made when the situation has changed for some reason and requires appropriate responses at the system level. For example, a person is hungry - this is reported to the "center" by sensors that register an increase in fasting secretion of gastric juice and peristalsis of the gastrointestinal tract, as well as sensors that register a decrease in blood glucose levels. In response, the peristalsis of the gastrointestinal tract increases reflexively and the secretion of gastric juice increases. The stomach is ready to receive a new portion of food. At the same time, optical sensors make it possible to see food products on the table, and a comparison of these images with models stored in the database of long-term memory suggests that there is an opportunity to satisfy hunger remarkably, while enjoying the look and taste of the food consumed. In this case, the central nervous system instructs the executive (effector) organs to take the necessary actions that will ultimately lead to saturation and elimination of the original cause of all these events. Thus, the goal of the system is to eliminate the cause of the disturbance by its actions. This goal is achieved in this case relatively easily: it is enough to reach out to the table, take the food lying there and eat it. However, it is clear that according to the same scheme, an arbitrarily complex scenario of actions can be constructed.
Hunger, love, family values, friendship, shelter, self-affirmation, craving for new things and love for beauty - this short list almost exhausts the motives for action. Sometimes they are overgrown with a huge number of incoming psychological and social complexities, closely intertwined with each other, but in the most basic form they remain the same, forcing a person to perform actions, whether in the time of Apuleius, Shakespeare or in our time.
Act - what does it mean in terms of systems? This means that the central processor, obeying the program embedded in it, taking into account all possible circumstances, makes a decision, i.e. builds a model of the required future and develops an algorithm for achieving this future. On the basis of this algorithm, orders are given to individual effector (executive) structures, and almost always they contain muscles, and in the process of fulfilling the order of the center, the body or its parts move in space.
And once the movement is carried out, it means that physical work is performed in the field of terrestrial gravity, and, consequently, energy is spent. Of course, the operation of the sensors and the processor also requires energy, but the energy flow increases many times when muscle contractions are turned on. Therefore, the system must take care of an adequate supply of energy, for which it is necessary to increase the activity of blood circulation, respiration and some other functions, as well as to mobilize the available reserves of nutrients.
Any increase in metabolic activity entails a violation of the constancy of the internal environment. This means that the physiological mechanisms of maintaining homeostasis should be activated, which, by the way, also need significant amounts of energy for their activity.
Being a complexly organized system, the body has not one, but several circuits of regulation. The nervous system is probably the main, but by no means the only regulatory mechanism. Very important role perform endocrine organs - endocrine glands, which chemically regulate the activity of almost all organs and tissues. In addition, each cell of the body has its own internal system of self-regulation.
It should be emphasized that an organism is an open system not only from a thermodynamic point of view, i.e., it exchanges with the environment not only energy, but also matter and information. We consume matter mainly in the form of oxygen, food and water, and we excrete it in the form of carbon dioxide, feces and sweat. As for information, each person is a source of visual (gestures, postures, movements), acoustic (speech, noise from movement), tactile (touch) and chemical (numerous smells that our pets perfectly distinguish) information.
Another important feature of the system is the finiteness of its dimensions. The organism is not smeared over the environment, but has a certain shape and is compact. The body is surrounded by a shell, a boundary that separates the internal environment from the external. The skin, which performs this role in the human body, is an important element of its design, since it is in it that many sensors are concentrated that carry information about the state of the outside world, as well as ducts for removing metabolic products and information molecules from the body. The presence of clearly defined boundaries turns a person into an individual who feels his separation from the surrounding world, his uniqueness and uniqueness. This is a psychological effect that occurs on the basis of the anatomical and physiological structure of the body.
The main structural and functional blocks that make up the body
Thus, the following can be attributed to the main structural and functional blocks that make up the body (each block includes several anatomical structures with many functions):
sensors (receptors), carrying information about the state of the external and internal environment;
central processor and control unit, including nervous and humoral regulation;
effector organs (primarily the musculoskeletal system), which ensure the execution of the orders of the "center";
an energy block that provides effector and all other structural components with the necessary substrate and energy;
a homeostatic block that maintains the parameters of the internal environment at the level necessary for life;
a shell that performs the functions of a border zone, reconnaissance, protection and all types of exchange with the environment.
..(PHYSIOLOGY OF CHILD DEVELOPMENT)
Tutorial
For students of higher pedagogical educational institutions
M.M. Bezrukikh I (1, 2), III (15), IV (18-23),
V.D. Sonkin I (1, 3), II (4-10), III (17), IV (18-22),
D.A. Farber I (2), III (11-14, 16), IV (18-23)
Reviewers:
doctor of biological sciences, head. Department of Higher Nervous Activity and Psychophysiology, St. Petersburg University, Academician of the Russian Academy of Education,
Professor A. S. Batuev; Doctor of Biological Sciences, Professor I.A. Kornienko
Bezrukikh M. M. and etc.
Age physiology: (Physiology of child development): Proc. allowance for students. higher ped. studies, institutions / M. M. Bezrukikh, V. D. Sonkin, D. A. Farber. - M.: Publishing Center "Academy", 2002. - 416 p. ISBN 5-7695-0581-8
The textbook presents modern concepts of human ontogenesis, taking into account the latest achievements in anthropology, anatomy, physiology, biochemistry, neuro- and psychophysiology, etc. The morphological and functional features of the child at the main stages of age development, their connection with the processes of socialization, including education and upbringing, are considered. The book is illustrated with a large number of diagrams, tables, drawings that facilitate the assimilation of the material, questions for self-examination are proposed.
AGE PHYSIOLOGY 1
Tutorial 1
FOREWORD 3
Section I INTRODUCTION TO AGE PHYSIOLOGY 7
Chapter 1
Chapter 2. THEORETICAL FOUNDATIONS OF AGE PHYSIOLOGY 18
(PHYSIOLOGY OF DEVELOPMENT) 18
Chapter 3. GENERAL PLAN OF THE STRUCTURE OF THE ORGANISM 28
Section II ORGANISM AND ENVIRONMENT 39
Chapter 4. GROWTH AND DEVELOPMENT 39
Chapter 5. ORGANISM AND ITS HABITAT 67
Chapter 6. INTERNAL ENVIRONMENT OF THE ORGANISM 82
Chapter 7. METABOLISM (METABOLISM) 96
Chapter 8. SYSTEM OF OXYGEN SUPPLY OF THE ORGANISM 132
Chapter 9. PHYSIOLOGY OF ACTIVITY AND ADAPTATION 162
Chapter 10
Section III THE ORGANISM AS A WHOLE 199
Chapter 11. NERVOUS SYSTEM: SIGNIFICANCE AND STRUCTURAL AND FUNCTIONAL ORGANIZATION 199
Chapter 12
Chapter 13. REGULATION OF THE FUNCTIONAL STATE OF THE BRAIN 219
Chapter 14. INTEGRATIVE ACTIVITY OF THE BRAIN 225
Chapter 15. CENTRAL MOVEMENT REGULATION 248
Chapter 16
Chapter 17
Section IV STAGES OF CHILD DEVELOPMENT 297
Chapter 18. INFANTITY (from 0 to 1 year) 297
Chapter 19. EARLY AGE 316
(FROM 1 YEAR TO 3 YEARS) 316
Chapter 20. PRESCHOOL 324
(FROM 3 TO 6-7 YEARS) 324
Chapter 21
Chapter 22
Chapter 23. SOCIAL FACTORS OF DEVELOPMENT AT DIFFERENT STAGES OF ONTOGENESIS 369
LITERATURE 382
FOREWORD
Elucidation of the patterns of child development, the specifics of the functioning of physiological systems at different stages of ontogenesis and the mechanisms that determine this specificity is necessary condition ensuring the normal physical and mental development of the younger generation.
The main questions that should arise from parents, teachers and psychologists in the process of raising and educating a child at home, in kindergarten or at school, at a counseling session or individual lessons - this is what he is, what are his characteristics, what option of training with him will be most effective. Answering these questions is not at all easy, because this requires deep knowledge about the child, the patterns of his development, age and individual characteristics. This knowledge is also extremely important for the development of the psychophysiological foundations of the organization. academic work development of adaptation mechanisms in the child, determining the impact on him innovative technologies etc.
Perhaps, for the first time, the importance of a comprehensive knowledge of physiology and psychology for a teacher and educator was singled out by the famous Russian teacher K.D. Ushinsky in his work “Man as an Object of Education” (1876). “The art of education,” wrote K.D. Ushinsky, “has the peculiarity that it seems familiar and understandable to almost everyone, and even an easy matter to others, and the more understandable and easier it seems, the less a person is theoretically familiar with it. and practically. Almost everyone admits that parenting requires patience; some think that it requires an innate ability and skill, i.e. skill; but very few have come to the conclusion that, in addition to patience, innate ability and skill, special knowledge is also needed, although our numerous wanderings could convince everyone of this. It was K.D.Ushinsky who showed that physiology is one of those sciences in which “facts are stated, compared and grouped, and those correlations of facts in which the properties of the object of education, i.e., a person, are found.” Analyzing the physiological knowledge that was known, and this was the time of the formation of age physiology, K.D. Ushinsky emphasized: “From this source, which was just opening, education almost did not draw yet.” Unfortunately, even now we cannot talk about the wide use of age-related physiology data in pedagogical science. The uniformity of programs, methods, textbooks is a thing of the past, but the teacher still does not take into account the age and individual characteristics of the child in the learning process.
At the same time, the pedagogical effectiveness of the learning process largely depends on how the forms and methods of pedagogical influence are adequate to the age-related physiological and psychophysiological characteristics of schoolchildren, whether the organization conditions correspond educational process the abilities of children and adolescents, whether the psychophysiological patterns of the formation of basic school skills - writing and reading, as well as basic motor skills in the process of classes are taken into account.
The physiology and psychophysiology of a child is a necessary component of the knowledge of any specialist working with children - a psychologist, educator, teacher, social pedagogue. “Upbringing and education deals with a holistic child, with his holistic activity,” said the well-known Russian psychologist and teacher V.V. Davydov. - This activity, considered as a special object of study, contains in its unity many aspects, including ... physiological (V.V. Davydov "Problems of developmental education." - M., 1986. - P. 167).
Age physiology is the science of the characteristics of the life of the body, the functions of its individual systems, the processes that take place in them, and the mechanisms of their regulation at different stages of individual development. Part of it is the study of the physiology of the child in different age periods.
A textbook on age-related physiology for students of pedagogical universities contains knowledge about human development at those stages when the influence of one of the leading factors of development - education - is most significant.
The subject of age physiology (physiology of child development) as academic discipline are the features of the development of physiological functions, their formation and regulation, the vital activity of the organism and the mechanisms of its adaptation to the external environment at different stages of ontogenesis.
Basic concepts of age physiology:
An organism is the most complex, hierarchically (subordinately) organized system of organs and structures that ensure vital activity and interaction with the environment. The elementary unit of the organism is the cell. A collection of cells that are similar in origin, structure and function forms a tissue. Tissues form organs that perform specific functions. Function - specific activity organ or system.
Physiological system - a set of organs and tissues related by a common function.
A functional system is a dynamic association of various organs or their elements, the activity of which is aimed at achieving a specific goal (useful result).
As for the structure of the proposed textbook, it is built in such a way that students have a clear idea of the patterns of development of the body in the process of ontogenesis, the features of each age stage.
We tried not to overload the presentation with anatomical data and at the same time considered it necessary to give basic ideas about the structure of organs and systems at different stages of age development, which is necessary for understanding the physiological patterns of organization and regulation of physiological functions.
The book consists of four sections. Section I - "Introduction to developmental physiology" - reveals the subject of developmental physiology as an integral part of developmental physiology, gives an idea of the most important modern physiological theories of ontogenesis, introduces basic concepts without which it is impossible to understand the main content of the textbook. In the same section, the most general idea of the structure of the human body and its functions is given.
Section II - "The Organism and the Environment" - gives an idea of the main stages and patterns of growth and development, the most important functions of the body that ensure the interaction of the body with the environment and its adaptation to changing conditions, the age development of the body and characteristic features stages of individual development.
Section III - "The Organism as a Whole" - contains a description of the activities of systems that integrate the body into a single whole. First of all, it is the central nervous system, as well as the autonomic nervous system and the system of humoral regulation of functions. The main patterns of age-related development of the brain and its integrative activity are the key aspect of the content of this section.
Section IV - "Stages of child development" - contains a morpho-physiological description of the main stages of child development from birth to adolescence. This section is most important for practitioners who work directly with the child, for whom it is important to know and understand the basic morphological and functional age-related characteristics of the child's body at each stage of its development. To understand the contents of this section, it is necessary to master all the material presented in the previous three. This section concludes with a chapter that examines the impact of social factors on child development.
At the end of each chapter, there are questions for independent work of students, which allow you to refresh the memory of the main provisions of the studied material that require special attention.
Section I INTRODUCTION TO AGE PHYSIOLOGY
Chapter 1
The relationship of age physiology with other sciences
By the time of birth, the child's body is still very far from a mature state. A human cub is born small, helpless, it cannot survive without the care and care of adults. It takes a long time for it to grow and become a full-fledged mature organism.
The section of physiological science that studies the biological patterns and mechanisms of growth and development is called age physiology. The development of a multicellular organism (and the human body consists of several billion cells) begins at the moment of fertilization. The entire life cycle of an organism, from conception to death, is called individual development, or ontogenesis.
Regularities and features of the life of the organism in the early stages of ontogenesis are traditionally the subject of research. age physiology (physiology of child development).
The physiology of child development concentrates its interest on those stages that are of greatest interest to the educator, teacher, school psychologist: from birth to morphofunctional and psychosocial maturation. Earlier stages related to intrauterine development are explored by science embryology. Later stages, from reaching maturity to old age, study normal physiology And gerontology.
Man in his development obeys all the basic laws established by Nature for any developing multicellular organism, and therefore developmental physiology is one of the sections of a much broader field of knowledge - developmental biology. At the same time, in the dynamics of growth, development and maturation of a person, there are many specific, special features that are inherent only in the species Homo sapience (Reasonable Man). In this plane, developmental physiology is closely intertwined with science anthropology which aims at the comprehensive study of man.
A person always lives in the specific conditions of the environment with which he interacts. Continuous interaction and adaptation to the environment is the general law of the existence of living things. Man has learned not only to adapt to the environment, but also to change the world around him in the necessary direction. However, this did not save him from the influence of environmental factors, and at different stages of age development, the set, strength of action and the result of the influence of these factors may be different. This determines the relationship of physiology with ecological physiology, which studies the impact on a living organism of various environmental factors and ways of adapting the organism to the action of these factors.
During periods of intensive development, it is especially important to know how environmental factors act on a person, how various risk factors influence. This has traditionally received increased attention. And here the physiology of development closely interacts with hygiene, since it is the physiological laws that most often act as the theoretical foundations of hygiene requirements and recommendations.
The role of living conditions, and not only "physical", but also social, psychological, in the formation of a healthy and adapted person is very great. A child should be aware of the value of his health from early childhood, possess the necessary skills to preserve it.
Formation of the value of health and a healthy lifestyle is the task of pedagogical valeology, which draws factual material and basic theoretical provisions from developmental physiology.
Finally, developmental physiology is the natural science basis pedagogy. At the same time, the physiology of development is inextricably linked with the psychology of development, since for each person his biological and personal make up a single whole. No wonder any biological damage (illness, injury, genetic disorders, etc.) inevitably affects the development of the individual. The teacher should be equally well versed in the problems of developmental psychology and physiology of development: only in this case his activity will bring real benefit to his students.
MM. Bezrukikh, V.D. Sonkin, D.A. farber
Age physiology: (Physiology of child development)
Tutorial
For students of higher pedagogical educational institutions
Reviewers:
doctor of biological sciences, head. Department of Higher Nervous Activity and Psychophysiology of St. Petersburg University, Academician of the Russian Academy of Education, Professor A.S. Batuev;
Doctor of Biological Sciences, Professor I.A. Kornienko
FOREWORD
Elucidation of the patterns of child development, the specifics of the functioning of physiological systems at different stages of ontogenesis and the mechanisms that determine this specifics, is a necessary condition for ensuring the normal physical and mental development of the younger generation.
The main questions that parents, educators and psychologists should have in the process of raising and educating a child at home, in kindergarten or at school, at a consultative appointment or individual lessons, are what kind of child he is, what are his features, what option of training with him will be the most effective. Answering these questions is not at all easy, because this requires deep knowledge about the child, the patterns of his development, age and individual characteristics. This knowledge is also extremely important for developing the psychophysiological foundations for organizing educational work, developing mechanisms for adaptation in a child, determining the impact of innovative technologies on him, etc.
Perhaps, for the first time, the importance of a comprehensive knowledge of physiology and psychology for a teacher and educator was highlighted by the famous Russian teacher K.D. Ushinsky in his work "Man as an object of education" (1876). “The art of education,” wrote K.D. Ushinsky, - has the peculiarity that it seems familiar and understandable to almost everyone, and even an easy matter to others - and the more understandable and easier it seems, the less a person is familiar with it theoretically and practically. Almost everyone admits that parenting requires patience; some think that it requires an innate ability and skill, that is, a habit; but very few have come to the conclusion that, in addition to patience, innate ability and skill, special knowledge is also needed, although our numerous wanderings could convince everyone of this. It was K.D. Ushinsky showed that physiology is one of those sciences in which "facts are stated, compared and grouped, and those correlations of facts in which the properties of the object of education, i.e., a person, are found." Analyzing the physiological knowledge that was known, and this was the time of the formation of age physiology, K.D. Ushinsky emphasized: “From this source, which is just opening up, education has almost not yet scooped.” Unfortunately, even now we cannot talk about the wide use of age-related physiology data in pedagogical science. The uniformity of programs, methods, textbooks is a thing of the past, but the teacher still does not take into account the age and individual characteristics of the child in the learning process.
At the same time, the pedagogical effectiveness of the learning process largely depends on how the forms and methods of pedagogical influence are adequate to the age-related physiological and psychophysiological characteristics of schoolchildren, whether the conditions for organizing the educational process correspond to the capabilities of children and adolescents, whether the psychophysiological patterns of the formation of basic school skills - writing and reading, as well as basic motor skills in the process of classes.
The physiology and psychophysiology of a child is a necessary component of the knowledge of any specialist working with children - a psychologist, educator, teacher, social pedagogue. “Upbringing and education deals with a holistic child, with his holistic activity,” said the well-known Russian psychologist and teacher V.V. Davydov. - This activity, considered as a special object of study, contains in its unity many aspects, including ... physiological "(V.V. Davydov" Problems of developmental education. - M., 1986. - P. 167).
age physiology- the science of the features of the life of the body, the functions of its individual systems, the processes occurring in them, and the mechanisms of their regulation at different stages of individual development. Part of it is the study of the physiology of the child in different age periods.
A textbook on age-related physiology for students of pedagogical universities contains knowledge about human development at those stages when the influence of one of the leading factors of development - education - is most significant.
The subject of developmental physiology (physiology of child development) as an academic discipline is the features of the development of physiological functions, their formation and regulation, the vital activity of the organism and the mechanisms of its adaptation to the external environment at different stages of ontogenesis.
Basic concepts of age physiology:
organism - the most complex, hierarchically (subordinately) organized system of organs and structures that ensure vital activity and interaction with the environment. The basic unit of an organism is cell . A collection of cells that are similar in origin, structure and function forms the cloth . Tissues form organs that perform specific functions. Function - specific activity of an organ or system.
Physiological system - a set of organs and tissues related by a common function.
Functional system - dynamic association of various organs or their elements, whose activities are aimed at achieving a specific goal (beneficial result).
With regard to the structure of the proposed study guide, then it is built in such a way that students have a clear idea of the patterns of development of the organism in the process of ontogenesis, about the features of each age stage.
We tried not to overload the presentation with anatomical data and at the same time considered it necessary to give basic ideas about the structure of organs and systems at different stages of age development, which is necessary for understanding the physiological patterns of organization and regulation of physiological functions.
The book consists of four sections. Section I - "Introduction to developmental physiology" - reveals the subject of developmental physiology as an integral part of developmental physiology, gives an idea of the most important modern physiological theories of ontogenesis, introduces basic concepts, without which it is impossible to understand the main content of the textbook. In the same section, the most general idea of the structure of the human body and its functions is given.
Section II - "The Organism and the Environment" - gives an idea of the main stages and patterns of growth and development, the most important functions of the body that ensure the interaction of the body with the environment and its adaptation to changing conditions, the age development of the body and the characteristic features of the stages of individual development.
Section III - "The Organism as a Whole" - contains a description of the activities of systems that integrate the body into a single whole. First of all, it is the central nervous system, as well as the autonomic nervous system and the system of humoral regulation of functions. The main patterns of age-related development of the brain and its integrative activity are the key aspect of the content of this section.
Section IV - "Stages of Child Development" - contains a morphophysiological description of the main stages of child development from birth to adolescence. This section is most important for practitioners who work directly with the child, for whom it is important to know and understand the basic morphological and functional age-related characteristics of the child's body at each stage of its development. To understand the contents of this section, it is necessary to master all the material presented in the previous three. This section concludes with a chapter that examines the impact of social factors on child development.
At the end of each chapter are questions for independent work students, which allow you to refresh the memory of the main provisions of the studied material that require special attention.
INTRODUCTION TO AGE PHYSIOLOGY
Chapter 1
The relationship of age physiology with other sciences
By the time of birth, the child's body is still very far from a mature state. A human cub is born small, helpless, it cannot survive without the care and care of adults. It takes a long time for it to grow and become a full-fledged mature organism.
age physiology a section of human and animal physiology that studies the patterns of formation and development of the physiological functions of the body throughout ontogeny -
from egg fertilization to the end of life. V. f. establishes the features of the functioning of the body, its systems, organs and tissues at different age stages. The life cycle of all animals and humans consists of certain stages or periods. Thus, the development of mammals goes through the following periods: intrauterine (including the phases of embryonic and placental development), newborns, milk, puberty, maturity and aging. The following age periodization has been proposed for humans (Moscow, 1967): 1. Newborn (from 1 to 10 days). 2. Breast age (from 10 days to 1 year). 3. Childhood: a) early (1-3 years), b) first (4-7 years), c) second (8-12 years old boys, 8-11 years old girls). 4. Adolescence (13-16 years old boys, 12-15 years old girls). 5. Youthful age (17-21 years old boys, 16-20 years old girls). 6. Mature age: 1st period (22-35 years old men, 21-35 years old women); 2nd period (36-60 years old men, 36-55 years old women). 7. Old age (61-74 years old men, 56-74 years old women). 8. Senile age (75-90 years). 9. Long-livers (90 years and above). I. M. Sechenov (1878) pointed out the importance of studying physiological processes in ontogenetic terms. The first data on the features of the functioning of the nervous system in the early stages of ontogenesis were obtained in the laboratories of I. R. Tarkhanov a (1879) and V. M. Bekhterev a (1886). Researches on V. f. carried out in other countries. The German physiologist W. Preyer (1885) studied blood circulation, respiration, and other functions of developing mammals, birds, and amphibians; Czech biologist E. Babak studied the ontogeny of amphibians (1909). The publication of the book by N. P. Gundobin “Features childhood”(1906) laid the foundation for a systematic study of the morphology and physiology of the developing human organism. Works on V. f. received a large scale from the 2nd quarter of the 20th century, mainly in the USSR. The structural and functional features of the age-related development of individual organs and their systems were revealed: higher nervous activity (L. A. Orbeli, N. I. Krasnogorsky, A. G. Ivanov-Smolensky, A. A. Volokhov, N. I. Kasatkin, M M. Koltsova, A. N. Kabanov), the cerebral cortex, subcortical formations and their relationships (P. K. Anokhin, I. A. Arshavsky, E. Sh. Airapetyants, A. A. Markosyan, A. A. Volokhov and others), the musculoskeletal system (V. G. Shtefko, V. S. Farfel, L. K. Semyonova), the cardiovascular system and respiration (F. I. Valker, V. I. Puzik, N V. Lauer, I. A. Arshavsky, V. V. Frolkis), blood systems (A. F. Tur, A. A. Markosyan). Problems of age-related neurophysiology and endocrinology, age-related changes in metabolism and energy, cellular and subcellular processes, as well as acceleration are being successfully developed (See Acceleration) -
accelerate the development of the human body. The concepts of ontogenesis and aging were formed: A. A. Bogomolets - on the role of the physiological system of connective tissue; A. V. Nagorny - on the significance of the intensity of protein self-renewal (decaying curve); P. K. Anokhin - about systemogenesis, i.e. maturation in ontogenesis of certain functional systems that provide one or another adaptive reaction; I. A. Arshavsky - about the importance of motor activity for the development of the body (energy rule of skeletal muscles); A. A. Markosyan - about reliability biological system, which ensures the development and existence of the organism under changing environmental conditions. In researches on V. f. use the methods used in physiology, as well as comparative method, i.e., by comparing the functioning of certain systems at different ages, including the elderly and senile. V. f. closely related to related sciences - morphology, biochemistry, biophysics, anthropology. It is the scientific and theoretical basis of such branches of medicine as pediatrics, hygiene of children and adolescents, gerontology, geriatrics, as well as pedagogy, psychology, physical education, etc. Therefore, V. F. is actively developing in the system of institutions related to the protection of children's health, which have been organized in the USSR since 1918, and in the system of physiological institutes and laboratories of the Academy of Sciences of the USSR, the Academy of Sciences of the USSR, the Academy of Medical Sciences of the USSR, and others. introduced as a compulsory subject at all faculties of pedagogical institutes. In coordination of researches on V. f. an important role is played by conferences on age-related morphology, physiology and biochemistry, convened by the institute of age-related physiology of the Academy of Pedagogical Sciences of the USSR. The 9th conference (Moscow, April 1969) brought together the work of 247 scientific and educational institutions Soviet Union. Lit.: Kasatkin N. I., Early conditioned reflexes in human ontogenesis, M., 1948; Krasnogorsky N. I., Proceedings on the study of higher nervous activity of humans and animals, vol. 1, M., 1954; Parkhon K. I., Age biology, Bucharest, 1959; Paper A., Features of the activity of the child's brain, trans. from German, L., 1962; Nagorny A. V., Bulankin I. N., Nikitin V. N., The problem of aging and longevity, M., 1963; Essays on the physiology of the fetus and newborn, ed. V. I. Bodyazhina. Moscow, 1966. Arshavsky I. A., Essays on age physiology, M., 1967; Koltsova M. M., Generalization as a function of the brain, L., 1967; Chebotarev D. F., Frolkis V. V., Cardiovascular system during aging, L., 1967; Volokhov A. A., Essays on the physiology of the nervous system in early ontogenesis, L., 1968; Ontogeny of the blood coagulation system, ed. A. A. Markosyan, L., 1968; Farber D. A., Functional maturation of the brain in early ontogenesis, M., 1969; Fundamentals of morphology and physiology of the organism of children and adolescents, ed. A. A. Markosyan. Moscow, 1969. A. A. Markosyan.
Great Soviet Encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .
See what "Age Physiology" is in other dictionaries:
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AHATOMO-PHYSIOLOGICAL CHARACTERISTICS OF CHILDREN- age features of the structure, functions of children. organism, their transformation in the process of individual development. Knowledge and accounting of A. f. about. are necessary for the correct organization of the education and upbringing of children of different ages. The age of the children is conditional ... ... Russian Pedagogical Encyclopedia
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