The physical development of a person is a complex of morphological and functional properties of the body that determine the shape, size, body weight and its structural and mechanical qualities.

Introduction

Signs of physical development are variable. The physical development of a person is the result of the influence of hereditary factors (genotype) and environmental factors, and for a person - the whole complex of social conditions ( phenotype). With age, the value of heredity decreases, the leading role passes to individually acquired features.
The physical development of children and adolescents is associated with growth. Each age period - infancy, childhood, adolescence and youth - is characterized by specific features of the growth of individual parts of the body. In each age period, the child's body has a number of characteristic features that are unique to this age. Between the body of a child and an adult, there are not only quantitative differences (body size, weight), but, above all, qualitative ones.
Currently, there is an acceleration of human physical development. This phenomenon is called acceleration.
In my work, I will try to briefly characterize each of the main stages of individual development of a person.

The main stages of individual human development

When studying human development, its individual and age characteristics in anatomy and other disciplines, they are guided by scientifically based data on age periodization. The scheme of age periodization of human development, taking into account anatomical, physiological, and social factors, was adopted at the VII Conference on Problems of Age Morphology, Physiology, and Biochemistry (1965). It distinguishes twelve age periods (Table 1). Table 1

Individual development, or development in ontogeny, occurs in all periods of life - from conception to death. In human ontogenesis, two periods are distinguished: before birth (intrauterine, prenatal - from the Greek natos - born) and after birth (extrauterine, postnatal).

Prenatal ontogeny

To understand the individual structural features of the human body, it is necessary to get acquainted with the development of the human body in the prenatal period. The fact is that each person has his own individual characteristics of external appearance and internal structure, the presence of which is determined by two factors. This is heredity, traits inherited from parents, as well as the result of the influence of the external environment in which a person grows, develops, studies, works.
In the intrauterine period, from conception to birth, for 280 days (9 calendar months), the embryo (embryo) is located in the mother's body (from the moment of fertilization to birth). During the first 8 weeks, the main processes of the formation of organs and body parts take place. This period is called the embryonic (embryonic), and the body of the future person is the embryo (embryo). From the age of 9 weeks, when the main external human features begin to appear, the body is called a fetus, and the period is fetal (fetal - from the Greek fetus - fetus).
The development of a new organism begins with the process of fertilization (fusion of sperm and egg), which usually occurs in the fallopian tube. Merged sex cells form a qualitatively new unicellular embryo - a zygote that has all the properties of both germ cells. From this moment, the development of a new (daughter) organism begins.
The optimal conditions for the interaction of sperm and egg are usually created within 12 hours after ovulation. The union of the nucleus of the spermatozoon with the nucleus of the ovum leads to the formation in a unicellular organism (zygote) of a diploid set of chromosomes characteristic of a human being (46). The sex of the unborn child is determined by the combination of chromosomes in the zygote and depends on the father's sex chromosomes. If the egg is fertilized by a sperm with the sex chromosome X, then two X chromosomes appear in the resulting diploid set of chromosomes, which are characteristic of the female body. When fertilized by a sperm with a Y sex chromosome, a combination of XY sex chromosomes is formed in the zygote, which is characteristic of the male body.
The first week of embryo development is the period of crushing (division) of the zygote into daughter cells (Fig. 1). Immediately after fertilization, during the first 3-4 days, the zygote divides and simultaneously moves along the fallopian tube towards the uterine cavity. As a result of division of the zygote, a multicellular vesicle is formed - a blastula with a cavity inside (from the Greek blastula - sprout). The walls of this vesicle are formed by two types of cells: large and small. From the outer layer of small cells, the walls of the vesicle are formed - the trophoblast. Subsequently, trophoblast cells form the outer layer of the membranes of the embryo. Larger dark cells (blastomeres) form a cluster - an embryoblast (embryonic nodule, embryo rudiment), which is located medially from the trophoblast. From this accumulation of cells (embryoblast), the embryo and adjacent extraembryonic structures (except for the trophoblast) develop.

Fig.1. A - fertilization: 1 - sperm; 2 - egg; B; C - crushing of the zygote, D - morublastula: 1 - embryoblast; 2 - trophoblast; D - blastocyst: 1-embryoblast; 2 - trophoblast; 3 - amnion cavity; E - blastocyst: 1-embryoblast; 2-amnion cavity; 3 - blastocoel; 4 - embryonic endoderm; 5-amnionitic epithelium - F - I: 1 - ectoderm; 2 - endoderm; 3 - mesoderm.
A small amount of fluid accumulates between the surface layer (trophoblast) and the germinal nodule. By the end of the 1st week of development (6-7th day of pregnancy), the embryo enters the uterus and is introduced (implanted) into its mucous membrane; implantation lasts about 40 hours. The surface cells of the embryo that form the vesicle, the trophoblast (from the Greek trophe - nutrition), secrete an enzyme that loosens the surface layer of the uterine mucosa, which is prepared for the introduction of the embryo into it. The emerging villi (outgrowths) of the trophoblast come into direct contact with the blood vessels of the mother's body. Numerous trophoblast villi increase the surface of its contact with the tissues of the uterine mucosa. The trophoblast turns into a nutrient membrane of the embryo, which is called the villous membrane (chorion). At first, the chorion has villi on all sides, then these villi remain only on the side facing the wall of the uterus. In this place, a new organ develops from the chorion and the uterine mucosa adjacent to it - the placenta (children's place). The placenta is the organ that connects the mother's body with the fetus and provides its nutrition.
The second week of the life of the embryo is the stage when the embryoblast cells are divided into two layers (two plates), from which two vesicles are formed (Fig. 2). From the outer layer of cells adjacent to the trophoblast, an ectoblastic (amniotic) vesicle is formed. An endoblastic (yolk) vesicle is formed from the inner layer of cells (the rudiment of the embryo, the embryoblast). The bookmark ("body") of the embryo is located where the amniotic vesicle is in contact with the yolk sac. During this period, the embryo is a two-layer shield, consisting of two sheets: the outer germinal (ectoderm) and the inner germinal (endoderm).

Fig.2. The position of the embryo and embryonic membranes at different stages of human development: A - 2-3 weeks; B - 4 weeks: 1 - amnion cavity; 2 - the body of the embryo; 3 - yolk sac; 4 - tropholast; B - 6 weeks; D - fetus 4-5 months: 1 - body of the embryo (fetus); 2 - amnion; 3 - yolk sac; 4 - chorion; 5 - umbilical cord.
The ectoderm faces the amniotic sac, and the endoderm is adjacent to the yolk sac. At this stage, the surfaces of the embryo can be determined. The dorsal surface is adjacent to the amniotic vesicle, and the ventral surface to the yolk sac. The trophoblast cavity around the amniotic and vitelline vesicles is loosely filled with strands of cells of the extraembryonic mesenchyme. By the end of the 2nd week, the length of the embryo is only 1.5 mm. During this period, the germinal shield thickens in its posterior (caudal) part. Here, in the future, axial organs (chord, neural tube) begin to develop.
The third week of the life of the embryo is the period of formation of a three-layer shield (embryo). The cells of the outer, ectodermal plate of the germinal shield are displaced towards its posterior end. As a result, a cell ridge (primary streak) is formed, which is elongated in the direction of the longitudinal axis of the embryo. In the head (front) part of the primary strip, cells grow and multiply faster, resulting in a slight elevation - the primary nodule (Hensen's nodule). The location of the primary nodule indicates the cranial (head end) of the body of the embryo.
Rapidly multiplying, the cells of the primary streak and the primary nodule grow to the sides between the ectoderm and endoderm, thus forming the median germ layer - the mesoderm. The cells of the mesoderm located between the sheets of the shield are called the intraembryonic mesoderm, and those that have moved beyond it are called the extraembryonic mesoderm.
Part of the mesoderm cells within the primary nodule grows especially actively forward from the head and tail ends of the embryo, penetrates between the outer and inner sheets and forms a cell strand - the dorsal string (chord). At the end of the 3rd week of development, active cell growth occurs in the anterior part of the outer germ layer - the neural plate is formed. This plate soon bends, forming a longitudinal groove - the neural groove. The edges of the groove thicken, approach and fuse with each other, closing the neural groove into the neural tube. In the future, the entire nervous system develops from the neural tube. The ectoderm closes over the formed neural tube and loses contact with it.
In the same period, a finger-like outgrowth, the alantois, penetrates from the back of the endodermal plate of the germinal shield into the extraembryonic mesenchyme (the so-called amniotic stalk), which does not perform certain functions in humans. In the course of the allantois, blood umbilical (placental) vessels sprout from the embryo to the chorion villi. A cord containing blood vessels that connects the embryo to the extra-embryonic membranes (placenta) forms the ventral stalk.
Thus, by the end of the 3rd week of development, the human embryo looks like a three-layer plate, or a three-layer shield. In the region of the outer germ layer, the neural tube is visible, and deeper - the dorsal string, i.e. axial organs of the human embryo appear. By the end of the third week of development, the length of the embryo is 2-3 mm.
The fourth week of life - the embryo, which has the form of a three-layer shield, begins to bend in the transverse and longitudinal directions. The embryonic shield becomes convex, and its edges are delimited from the amnion surrounding the embryo by a deep furrow - the trunk fold. The body of the embryo from a flat shield turns into a three-dimensional one, the ectoderm covers the body of the embryo from all sides.
From the ectoderm, the nervous system, the epidermis of the skin and its derivatives, the epithelial lining of the oral cavity, the anal part of the rectum, and the vagina are further formed. The mesoderm gives rise to internal organs (except endoderm derivatives), the cardiovascular system, the organs of the musculoskeletal system (bones, joints, muscles), and the skin itself.
The endoderm, which is inside the body of the human embryo, rolls up into a tube and forms the embryonic rudiment of the future intestine. The narrow opening connecting the embryonic intestine with the yolk sac later turns into the umbilical ring. From the endoderm, the epithelium and all the glands of the digestive system and respiratory tract are formed.
The embryonic (primary) intestine is initially closed in front and behind. In the anterior and posterior ends of the body of the embryo, invaginations of the ectoderm appear - the oral fossa (future oral cavity) and the anal (anal) fossa. Between the cavity of the primary intestine and the oral fossa there is a two-layer (ectoderm and endoderm) anterior (oropharyngeal) plate (membrane). Between the intestine and the anal fossa there is a cloacal (anal) plate (membrane), also two-layered. The anterior (oropharyngeal) membrane ruptures during the 4th week of development. At the 3rd month, the posterior (anal) membrane breaks.
As a result of bending, the body of the embryo is surrounded by the contents of the amnion - amniotic fluid, which acts as a protective environment that protects the embryo from damage, primarily mechanical (concussion).
The yolk sac lags behind in growth and at the 2nd month of intrauterine development looks like a small sac, and then it is completely reduced (disappears). The ventral stalk lengthens, becomes relatively thin and is later called the umbilical cord.
During the 4th week of development of the embryo, the differentiation of its mesoderm, which began on the 3rd week, continues. The dorsal part of the mesoderm, located on the sides of the chord, forms paired thickened protrusions - somites. Somites are segmented, i.e. divided into metameric regions. Therefore, the dorsal part of the mesoderm is called segmented. Segmentation of somites occurs gradually in the direction from front to back. On the 20th day of development, the 3rd pair of somites is formed, by the 30th day there are already 30 of them, and on the 35th day - 43-44 pairs. The ventral part of the mesoderm is not divided into segments. It forms two plates on each side (non-segmented part of the mesoderm). The medial (visceral) plate is adjacent to the endoderm (primary intestine) and is called the splanchnopleura. The lateral (outer) plate is adjacent to the wall of the body of the embryo, to the ectoderm, and is called the somatopleura.
From the splanchno- and somatopleura, the epithelial cover of the serous membranes (mesothelium), as well as the proper plate of the serous membranes and the subserous base, develop. The mesenchyme of the splanchnopleura also goes to the construction of all layers of the digestive tube, except for the epithelium and glands, which are formed from the endoderm. The space between the plates of the non-segmented part of the mesoderm turns into the body cavity of the embryo, which is subdivided into the peritoneal, pleural and pericardial cavities.

Fig.3. Cross section through the body of the embryo (diagram): 1 - neural tube; 2 - chord; 3 - aorta; 4 - sclerotome; 5 - myotome; 6 - dermatome; 7 - primary intestine; 8 - body cavity (as a whole); 9 - somatopleura; 10 - splanchnopleura.
The mesoderm on the border between the somites and the splanchnopleura forms nephrotomes (segmental legs), from which the tubules of the primary kidney, the sex glands, develop. From the dorsal part of the mesoderm - somites - three rudiments are formed. The anteromedial section of the somites (sclerotome) goes to the construction of skeletal tissue, giving rise to cartilage and bones of the axial skeleton - the spine. Lateral to it lies the myotome, from which the skeletal muscles develop. In the posterolateral part of the somite there is a site - the dermatome, from the tissue of which the connective tissue base of the skin is formed - the dermis.
In the head section on each side of the embryo from the ectoderm on the 4th week, the rudiments of the inner ear (first the auditory pits, then the auditory vesicles) and the future lens of the eye are formed. At the same time, the visceral sections of the head are rebuilt, which form the frontal and maxillary processes around the mouth bay. Behind (caudal) of these processes, the contours of the mandibular and sublingual (hyoid) visceral arches are visible.
Elevations are visible on the anterior surface of the torso of the embryo: cardiac, and behind it - hepatic tubercles. The recess between these tubercles indicates the place of formation of the transverse septum - one of the rudiments of the diaphragm. Caudal to the hepatic tubercle is the ventral stalk, which contains large blood vessels and connects the embryo to the placenta (umbilical cord). The length of the embryo by the end of the 4th week is 4-5 mm.

Fifth to eighth weeks

In the period from the 5th to the 8th week of the life of the embryo, the formation of organs (organogenesis) and tissues (histogenesis) continues. This is the time of early development of the heart and lungs, the complication of the structure of the intestinal tube, the formation of visceral arches, the formation of capsules of the sense organs. The neural tube completely closes and expands in the head region (the future brain). At the age of about 31-32 days (5th week), the length of the embryo is 7.5 mm. At the level of the lower cervical and 1st thoracic segments of the body, fin-like rudiments (buds) of the hands appear. By the 40th day, the rudiments of the legs are formed.
At the 6th week (parietal-coccygeal length of the embryo - 12 - 13 mm), the laying of the outer ear is noticeable, from the end of the 6-7th week - the laying of the fingers, and then the toes.
By the end of the 7th week (the length of the embryo is 19-20 mm), eyelids begin to form. Thanks to this, the eyes are outlined more clearly. On the 8th week (the length of the embryo is 28-30 mm), the laying of the organs of the embryo ends. From the 9th week, i.e. from the beginning of the 3rd month, the embryo (parietal-coccygeal length 39-41 mm) takes the form of a person and is called a fetus.

third to ninth months

Starting from three months and throughout the entire fetal period, further growth and development of the resulting organs and body parts occur. At the same time, the differentiation of the external genitalia begins. Nails are laid on the fingers. From the end of the 5th month (length 24.3 cm), eyebrows and eyelashes become noticeable. At the 7th month (length 37.1 cm), the eyelids open, fat begins to accumulate in the subcutaneous tissue. On the 10th month (length 51 cm) the fetus is born.

Critical periods of ontogeny a

In the process of individual development, there are critical periods when the sensitivity of the developing organism to the effects of damaging factors of the external and internal environment is increased. There are several critical periods of development. These most dangerous periods are:
1) the time of development of germ cells - ovogenesis and spermatogenesis;
2) the moment of fusion of germ cells - fertilization;
3) implantation of the embryo (4-8 days of embryogenesis);
4) formation of rudiments of axial organs (brain and spinal cord, spinal column, primary intestine) and formation of the placenta (3-8 weeks of development);
5) the stage of enhanced brain growth (15-20 weeks);
6) formation of the functional systems of the body and differentiation of the urogenital apparatus (20-24th week of the prenatal period);
7) the moment of the birth of the child and the neonatal period - the transition to extrauterine life; metabolic and functional adaptation;
8) the period of early and first childhood (2 years - 7 years), when the formation of relationships between organs, systems and apparatuses of organs ends;
9) adolescence (puberty - in boys from 13 to 16 years, in girls - from 12 to 15 years).
Simultaneously with the rapid growth of the organs of the reproductive system, emotional activity is activated.

Postnatal ontogeny. Neonatal period

Immediately after birth, there is a period called the neonatal period. The basis for this allocation is the fact that at this time the child is fed with colostrum for 8-10 days. Newborns in the initial period of adaptation to the conditions of extrauterine life are divided according to the level of maturity into full-term and premature. Intrauterine development of full-term babies lasts 39-40 weeks, premature babies - 28-38 weeks. When determining maturity, not only these terms are taken into account, but also the mass (weight) of the body at birth.
Newborns with a body weight of at least 2500 g (with a body length of at least 45 cm) are considered full-term, and newborns with a body weight of less than 2500 g are considered premature. In addition to weight and length, other dimensions are taken into account, for example, chest girth in relation to body length and head circumference in relation to chest circumference. It is believed that the girth of the chest at the level of the nipples should be more than 0.5 body length by 9-10 cm, and the girth of the head - more than the girth of the chest by no more than 1-2 cm.

Breast period

The next period - chest - lasts up to a year. The beginning of this period is associated with the transition to feeding "mature" milk. During the breast period, the greatest intensity of growth is observed, in comparison with all other periods of extrauterine life. Body length increases from birth to a year by 1.5 times, and body weight triples. From 6 months milk teeth begin to erupt. In infancy, uneven body growth is pronounced. In the first half of the year, babies grow faster than in the second. In each month of the first year of life, new indicators of development appear. In the first month, the child begins to smile in response to the appeal of adults, at 4 months. persistently tries to stand on legs (with support), at 6 months. tries to crawl on all fours, at 8 - makes attempts to walk, by the year the child usually walks.

early childhood period

The period of early childhood lasts from 1 year to 4 years. At the end of the second year of life, teething ends. After 2 years, the absolute and relative values ​​of annual body size increases rapidly decrease.

First childhood period

From the age of 4, the period of the first childhood begins, which ends at the age of 7. Starting from the age of 6, the first permanent teeth appear: the first molar (large molar) and the medial incisor on the lower jaw.
The age from 1 year to 7 years is also called the period of neutral childhood, since boys and girls almost do not differ from each other in size and body shape.

second childhood period

The period of second childhood lasts for boys from 8 to 12 years, for girls - from 8 to 11 years. During this period, sex differences in the size and shape of the body are revealed, and an increased growth of the body in length begins. Growth rates in girls are higher than in boys, since puberty in girls begins on average two years earlier. Increased secretion of sex hormones (especially in girls) causes the development of secondary sexual characteristics. The sequence of appearance of secondary sexual characteristics is fairly constant. In girls, the mammary glands first form, then pubic hair appears, then in the armpits. The uterus and vagina develop simultaneously with the formation of the mammary glands. To a much lesser extent, the process of puberty is expressed in boys. Only towards the end of this period do they begin to accelerate the growth of the testicles, scrotum, and then the penis.

Teenage years

The next period - adolescence - is also called puberty, or puberty. It continues in boys from 13 to 16 years old, in girls - from 12 to 15 years old. At this time, there is a further increase in growth rates - the puberty jump, which applies to all body sizes. The greatest increase in body length in girls occurs between 11 and 12 years, in body weight - between 12 and 13 years. In boys, an increase in length is observed between 13 and 14 years, and an increase in body weight between 14 and 15 years. The growth rate of body length is especially high in boys, as a result of which at the age of 13.5-14 they overtake girls in body length. Due to the increased activity of the hypothalamic-pituitary system, secondary sexual characteristics are formed. In girls, the development of the mammary glands continues, there is growth of hair on the pubis and in the armpits. The most clear indicator of puberty of the female body is the first menstruation.
In adolescence, there is an intensive puberty of boys. By the age of 13, their voice changes (mutates) and pubic hair appears, and at 14, hair appears in the armpits. At the age of 14-15, boys have their first wet dreams (involuntary eruptions of sperm).
In boys, compared with girls, the pubertal period is longer and the pubertal growth spurt is more pronounced.

adolescence

Adolescence lasts for boys from 18 to 21 years old, and for girls - from 17 to 20 years old. During this period, the growth process and the formation of the body basically end, and all the main dimensional features of the body reach the definitive (final) value.
In adolescence, the formation of the reproductive system and the maturation of the reproductive function are completed. The ovulatory cycles in a woman, the rhythm of testosterone secretion and the production of mature sperm in a man are finally established.

Mature, elderly, senile age

In adulthood, the shape and structure of the body change little. Between 30 and 50 years, body length remains constant, and then begins to decrease. In the elderly and senile age, gradual involutive changes in the body occur.

Individual differences in the process of growth and development

Individual differences in the process of growth and development can vary widely. The existence of individual fluctuations in the processes of growth and development served as the basis for the introduction of such a concept as biological age, or developmental age (as opposed to passport age).
The main criteria for biological age are:
1) skeletal maturity - (the order and timing of ossification of the skeleton);
2) dental maturity - (terms of eruption of milk and permanent teeth);
3) the degree of development of secondary sexual characteristics. For each of these biological age criteria - "external" (skin), "dental" and "bone" - rating scales and normative tables have been developed to determine the chronological (passport) age by morphological features.

Factors affecting individual development

Factors affecting individual development (ontogenesis) are divided into hereditary and environmental (influence of the external environment).
The degree of hereditary (genetic) influence is not the same at different stages of growth and development. The influence of hereditary factors on the total body size increases from the period of the newborn (tm) to the second childhood, with a subsequent weakening by the age of 12-15.
The influence of environmental factors on the processes of morphofunctional maturation of the body is clearly seen in the example of the timing of menarche (menstruation). Studies of growth processes in children and adolescents in various geographical areas have shown that climatic factors have almost no effect on growth and development, if living conditions are not extreme. Adaptation to extreme conditions causes such a profound restructuring of the functioning of the whole organism that it cannot but affect the growth processes.

Dimensions and proportions, body weight

Among the body sizes, total (from French total - whole) and partial (from Latin pars - part) are distinguished. Total (general) body dimensions are the main indicators of human physical development. These include body length and weight, as well as chest circumference. Partial (partial) dimensions of the body are terms of the total size and characterize the size of individual parts of the body.
Body sizes are determined during anthropometric surveys of various contingents of the population.
Most anthropometric indicators have significant individual fluctuations. Table 2 shows some average anthropometric indicators in postnatal ontogeny.
The proportions of the body depend on the age and gender of the person (Fig. 4). Body length and its age-related changes, as a rule, are individual. So, for example, differences in the body length of newborns during normal pregnancy are in the range of 49-54 cm. The largest increase in the body length of children is observed in the first year of life and averages 23.5 cm. In the period from 1 to 10 years, this indicator gradually decreases by an average of 10.5 - 5 cm per year. From the age of 9, sex differences in growth rate begin to appear. Body weight from the first days of life until about 25 years of age in most people gradually increases, and then remains unchanged.

Fig. 4 Changes in the proportions of body parts in the process of human growth.
KM - the middle line. The numbers on the right show the ratio of body parts in children and adults, the numbers below show the age.
table 2
Length, mass and body surface area in postiatal orthogenesis



Table 2
After the age of 60, body weight usually begins to gradually decrease, mainly as a result of atrophic changes in tissues and a decrease in their water content. The total body weight consists of a number of components: the mass of the skeleton, muscles, fatty tissue, internal organs and skin. In men, the average body weight is 52-75 kg, in women - 47-70 kg.
In the elderly and senile age, characteristic changes are observed not only in the size and weight of the body, but also in its structure; these changes are studied by the special science of gerontology (gerontos - old man). It should be emphasized that an active lifestyle, regular physical education slows down the aging process.

Acceleration

It should be noted that over the past 100-150 years there has been a noticeable acceleration in the somatic development and physiological maturation of children and adolescents - acceleration (from Latin acceleratio - acceleration). Another term for the same trend is "epochal shift". Acceleration is characterized by a complex set of interrelated morphological, physiological, and mental phenomena. To date, morphological indicators of acceleration have been determined.
Thus, the length of the body of children at birth over the past 100-150 years has increased by an average of 0.5-1 cm, and the weight - by 100-300 g. During this time, the mass of the placenta in the mother has also increased. There is also an earlier alignment of the ratios of chest and head girths (between the 2nd and 3rd month of life). Modern one-year-old children are 5 cm longer and 1.5-2 kg heavier than their peers in the 19th century.
The body length of preschool children over the past 100 years has increased by 10-12 cm, and for schoolchildren - by 10-15 cm.
In addition to an increase in body length and weight, acceleration is characterized by an increase in the size of individual parts of the body (segments of limbs, thickness of skin-fat folds, etc.). Thus, the increase in chest girth in relation to the increase in body length was small. The onset of puberty in modern adolescents occurs about two years earlier. The acceleration of development also affected motor functions. Modern teenagers run faster, jump further from a place, pull themselves up on the crossbar (horizontal bar) more times.
Epochal shift (acceleration) affects all stages of human life, from birth to death. For example, the length of the body of adults also increases, but to a lesser extent than in children and adolescents. So, at the age of 20-25 years, the body length of men increased by an average of 8 cm.
Acceleration covers the entire body, affecting the size of the body, the growth of organs and bones, the maturation of the sex glands and the skeleton. In men, changes in the process of acceleration are more pronounced than in women.
Men and women are distinguished by sexual characteristics. These are primary signs (genital organs) and secondary (for example, the development of pubic hair, the development of the mammary glands, a change in voice, etc.), as well as body features, proportions of body parts.
The proportions of the human body are calculated as a percentage according to the measurement of the longitudinal and transverse dimensions between the boundary points set on various protrusions of the skeleton.
The harmony of body proportions is one of the criteria for assessing the state of human health. With disproportion in the structure of the body, one can think of a violation of growth processes and the causes that caused it (endocrine, chromosomal, etc.). Based on the calculation of body proportions in anatomy, three main types of human physique are distinguished: mesomorphic, brachymorphic, dolichomorphic. The mesomorphic body type (normosthenics) includes people whose anatomical features approach the average parameters of the norm (taking into account age, gender, etc.). In people of the brachymorphic body type (hypersthenics), transverse dimensions predominate, muscles are well developed, they are not very tall. The heart is located transversely due to the high-standing diaphragm. In hypersthenics, the lungs are shorter and wider, the loops of the small intestine are located mainly horizontally. Persons of dolichomorphic body type (asthenics) are characterized by a predominance of longitudinal dimensions, have relatively longer limbs, poorly developed muscles and a thin layer of subcutaneous fat, and narrow bones. Their diaphragm is lower, so the lungs are longer, and the heart is located almost vertically. Table 3 shows the relative sizes of body parts in people of different body types.
Table 3

Conclusion

What can be the conclusion of the above?
Human growth is uneven. Each part of the body, each organ develops according to its own program. If we compare the growth and development of each of them with a long-distance runner, it is not difficult to find that during this many years of "running" the leader of the competition is constantly changing. In the first month of embryonic development, the head is in the lead. In a two-month-old fetus, the head is larger than the body. This is understandable: the brain is located in the head, and it is the most important organ that coordinates and organizes the complex work of organs and systems. The development of the heart, blood vessels and liver also begins early.
In a newborn baby, the head reaches half of its final size. Up to 5-7 years of age, there is a rapid increase in body weight and length. At the same time, the arms, legs and torso grow alternately: first, the arms, then the legs, then the torso. The size of the head during this period increases slowly.
At primary school age from 7 to 10 years, growth is slower. If earlier arms and legs grew more quickly, now the torso becomes the leader. It grows evenly, so that the proportions of the body are not violated.
In adolescence, the hands grow so intensively that the body does not have time to adapt to their new size, hence some clumsiness and sweeping movements. After that, the legs begin to grow. Only when they reach their final size does the torso join in the growth. First, it grows in height, and only then begins to grow in width. During this period, the physique of a person is finally formed.
If we compare the body parts of a newborn and an adult, it turns out that the size of the head has only doubled, the torso and arms have become three times larger, while the length of the legs has increased five times.
An important indicator of the development of the body is the appearance of menstruation in girls and wet dreams in boys, it indicates the onset of biological maturity.
Along with the growth of the body is its development. The growth and development of a person in different people occur at different times, so anatomists, doctors, physiologists distinguish between calendar age and biological age. Calendar age is calculated from the date of birth, biological age reflects the degree of physical development of the subject. The last one is different for each person. It may happen that people who are at the same biological age may differ by 2-3 years on the calendar, and this is completely normal. Girls tend to develop faster.

Literature

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5. Schmidt R., Tews G. Human Physiology: Per. from English. - M.: Mir, 1996.
6. Dragomilov A.G., Mash R.D. Biology: Man. - 2nd ed., revised. - M.: Ventana-Graf, 2004.
7. Sapin. M.R., Bryksina Z.G. Anatomy and physiology of children and adolescents: Proc. allowance for students. ped. universities. - M.: Publishing center "Academy", 2002.
8. Chusov Yu.N. Human Physiology: Proc. allowance for ped. Schools (special No. 1910). - M.: Enlightenment, 1981.
9. Encyclopedia "Round the World"
10. "Rusmedservice"
11. Encyclopedia "Wikipedia"

There are the following age periods of a person:

1. Childhood- from birth to the beginning of the period (12-13 years).

2. Adolescence(puberty) - from 12-13 to 16 years in girls and from 13-14 to 17-18 years in boys. This age is characterized by a sharp increase in body length with an annual increase of 5-6 cm. By the age of 15 (compared to a newborn) it triples and reaches an average of 158 cm in boys and 156 cm in girls. Body weight, respectively, is 48 and 49 kg. By the age of 14-15, all permanent ones appear, except for wisdom teeth. During this period, one of the most important age-related crises sets in - puberty, which is based on a change in the function of the endocrine system of the body, which leads to the appearance of secondary ones, the onset of menstruation in girls and the appearance in boys. The general metabolism in the body becomes intense, but unstable, labile. The mental life of a teenager is very complex and unstable and requires great tact and endurance from teachers, doctors and parents.

3. adolescence- from 16 to 25 years for women and from 17 to 26 years for men. Growth retardation is characteristic, the average annual increase is 0.5 cm. Wisdom teeth usually appear at this age.

4. adult age- from 25 to 40 years for women and from 26 to 45 years for men. The period of relative stabilization of morphological and metabolic processes.

5. Mature age- from 40 to 55 years for women and from 45 to 60 years for men. During this period, the second most important age crisis sets in - which is especially pronounced in women. Menopause is associated with the extinction of the functions of the sex glands and the restructuring of a number of hormonal systems of the body. The mental sphere and metabolism are characterized by significant lability.

6. Elderly age- from 55 to 75 years for women and from 60 to 75 years for men.

7. Senile age- over 75 years for women and men. The general involution of the organism begins to develop.

Sometimes it is proposed to allocate a special age of centenarians for persons 90 years of age and older.

Accurate age determination is essential in clinical and forensic practice. Age can be judged on the basis of data on height, body weight, number of teeth, skin condition. With age, wrinkles appear on the face of a person. By the age of 20 - frontal and nasolabial, by 25 years at the outer edges behind the ears, by 30 years - infraorbital, by 40 years - cervical, by 55 years - on the earlobes, hands, chin. However, all these criteria are very relative.

A more accurate method of determining age is to determine (radiologically) the so-called. Its definition is based on patterns in ossification associated with age periods. So, for example, ossification points in the distal epiphysis of the radius appear at 12-14 months. in girls and at 16-18 months. in boys. in the distal epiphysis of the ulna at the age of 19 and 20, respectively. As a rule, a snapshot of the hand and distal bones is used to determine bone age. Knowing the time of appearance of ossification points and synostoses, it is possible to determine the age of a person with a high degree of accuracy.

Age periods in children. The period of childhood is characterized by the constant development and growth of the child's body. There is no strict line between the individual stages of development.

Childhood is preceded by a period in which the stage of embryonic development (the first 3 months) and the stage of placental development (from the 3rd to the 9th month) are distinguished.

The extrauterine period of development is divided into several periods: 1) newborns, lasting up to 4 weeks of life; 2) infancy, lasting from 4 weeks to 1 year; 3) pre-preschool, or nursery - from 1 year to 3 years; 4) preschool (kindergarten period) - from 3 to 7 years; 5) junior school - from 7 to 12 years; 6) senior school (adolescent, or puberty) - from 12 to 18 years (see above).

The neonatal period is characterized by incomplete development of all organs and systems. During this period, the child's body adapts to environmental conditions. Insufficient functional ability of various organs is the cause of the development of a number of disorders in which it is difficult to distinguish between physiological and pathological conditions (physiological and, physiological weight loss and others). The newborn is extremely susceptible to coccal infection, which requires maximum care in the care of a child of this age (see).

Breast age. The period of infancy is characterized by the intensity of growth and development of the child's body, which leads to a relatively large need for high-calorie food and requires proper nutrition. If the quality and quantity of food are violated, eating disorders are possible and. Due to the relative functional weakness of the digestive organs, the child eats mainly dairy food. During this period, the child is also helpless and requires special care.

In an infant, the first signaling system is formed. Children begin to recognize objects and faces orient themselves in the environment.

Rapid exhaustion of the central nervous system. requires a large number of hours of sleep and proper alternation of sleep and wakefulness.

The weakness of immunobiological defense mechanisms makes children in the first months of life more susceptible to septic processes. At 2-5 months. the child is most vulnerable to infections due to a decrease in passive and insufficient production of active acquired immunity. In infancy, the manifestation of constitutional anomalies is characteristic, most often exudative-catarrhal diathesis (see).

preschool age in its biological characteristics, it has common features with infancy and preschool age. By the end of the first year, especially after two years, it develops intensively. At this age, appropriate organizational measures are required to ensure the correct regimen, education, sufficient rest and further development of the child. In preschool age, acute infections become more frequent mainly due to insufficient production of active immunity. This requires a timely child, as well as measures to protect the child from infection.

preschool age characterized by high mobility of the child, his activity. Children are much more involved in sports activities.

In this period of childhood, it is especially important to properly organize outdoor games, manual labor, etc. When developing a daily routine, especially organizing walks, it must be remembered that the child gets tired very quickly with slow non-stop walking. At preschool age, domestic and street injuries become more frequent; the incidence of acute infections increases significantly.

Junior school age characterized by increased development of muscles, but the growth of the child slows down somewhat. The child develops in the school community and lives by its interests. Physical education classes should be organized so that they do not tire the child, but contribute to an increase in metabolic processes and the functions of all body systems.

With a significant school load, improper organization of sleep and rest, the development of neurotic reactions is possible. For primary school age, a high incidence of acute infections is characteristic, diseases that are rare in pre-school age appear (, functional cardiovascular disorders, and others).

senior school age. Physiologically, it is characterized by the maturation of the gonads. sex glands dramatically change the course of all life processes and affect the functional state of the nervous system. In adolescents, a number of shifts occur in (pulse instability, etc.).

Uneven mood, increased irritability, fatigue are also noted. In adolescence, the morphological and physiological features that distinguish a child from an adult gradually smooth out and disappear. The course of diseases acquires clinical features characteristic of adults. See also .

§ 15.1. PERIODIZATION OF AGE DEVELOPMENT

Mental development is a process that unfolds over time and is characterized by both quantitative and qualitative changes. According to the definition of B. G. Ananiev, age development has two properties - metric and topological. The metric property means the duration of the course of certain mental processes and states, as well as the temporal characteristic of changes in the psyche that occur throughout a person's life. The metric property is measured by time intervals (days, months, years, etc.) or indicators of the dynamics of changes in a particular mental phenomenon (tempo, speed, acceleration). In the process of studying the temporal aspect of age development, temporal patterns were identified, such as unevenness and heterochrony. The unevenness of age development is expressed in the fact that individual mental functions and personal qualities of a person have a certain trajectory of changes over time, which can be both simple and complex, curvilinear in nature. In other words, the growth and aging of mental functions occurs unevenly, at different rates, which complicates the definition of different periods of a person's age development. The unevenness of mental development is influenced by historical time. The same properties function at different rates depending on the generation to which the individual belongs. Thus, the same periods of time, the volume of knowledge and the system of intellectual operations change significantly with the general progress of education and culture. in the 20th century compared to the 19th century. the pace and timing of the completion of maturation change, the phenomena of acceleration, or acceleration, of general somatic and neuropsychic development are observed, and at the same time, slowing down the aging process.

Another temporal pattern is expressed in the heterochrony of age development. When comparing the rates of variability of mental functions and properties with each other, a difference in timing is revealed in the passage of phases of age development, growth, achievement of maturity and evolution, which indicates the complexity and inconsistency of age development. Heterochrony can be intrafunctional, when certain aspects of mental function develop at different times, and interfunctional, in which various functions go through phases of their development at different times. Intrafunctional heterochrony refers to the difference in timing of aging of various types of color sensitivity. With age, sensitivity to blue and red colors ages most quickly, and sensitivity to yellow and green colors (according to Smith) turns out to be more stable with age. Interfunctional heterochrony refers to the discrepancy in time between the achievements of the optimum of sensory and intellectual, creative abilities and social development. Sensory development reaches a maturity phase at 18–25 years (according to Lazarev), intellectual, creative abilities can reach their optimum on average much later - at 35 years (according to Leman), and personal maturity - at 50–60 years. All this creates favorable opportunities for the age-related individual development of a person throughout his life. During the period of growth, those functions that are of paramount importance for the formation of other forms of the psyche develop most rapidly. So, in early preschool childhood, orientation in space is formed, and then later the child learns the concepts of time. During the period of aging, heterochrony ensures the preservation and further development of some functions at the expense of others, which at this time weaken and involute. Awareness, vocabulary of an elderly person can increase, while psychomotor and sensory-perceptual functions deteriorate if there is no systematic training for them and they are not included in professional activities.

No less important than the metric property is the topological property of age development. It means the certainty of a particular state, phase or period of the formation of an individual. Since age-related development as a holistic formation is a complex dynamic system, its qualitative topological features can be determined by studying the structural features of the interconnections of its various aspects, highlighting the leading, backbone factors that are associated with the specifics of a given period of life.

In modern periodizations of age development, metric and topological characteristics are used in a single classification scheme. The discrepancies of various periodizations, mismatches of boundaries for different periods are mainly associated with the inconsistency of mental development, due to the action of temporal patterns, unevenness and heterochrony, and with the topological complexity of various phases, the dynamics of the relationship between biological and social throughout the entire life cycle of a person. The structure of the life path and its main points (start, optima, finish) change in the course of historical development, from generation to generation, which also affects the periodization of age development.

The various age classifications can be divided into two groups. Private classifications are devoted to individual segments of life, more often children's and school years. General classifications cover the entire life path of a person. Particular is the classification of the development of intelligence by J. Piaget, who distinguishes three main periods of its formation from the moment of birth to 15 years:

period of sensorimotor intelligence (0–2 years). There are six main stages in this period;

the period of preparation and organization of specific operations (3 years - 11 years). Two sub-periods are distinguished here - the sub-period of pre-operational representations (3 years - 7 years), in which Piaget distinguishes three stages, and the sub-period of specific operations (8-11 years);

and, finally, the period of formal operations (12-15 years old), when a teenager can successfully act in relation not only to the reality around him, but also to the world of abstract, verbal assumptions.

In the classification of D. B. Elkonin, also belonging to the first group, three epochs of life are considered - early childhood, childhood and adolescence. In each era, there is a change in the leading types of activity that cause changes in the development of the child and his transition to a new era. Following the periods in which the predominant development of the motivational sphere takes place, periods naturally follow in which there is a predominant development of socially developed methods of acting with objects, the formation of the operational and technical capabilities of children. Elkonin arranged the selected types of activity in the system "child - social adult" and in the system "child - social object" in the sequence in which they become leading. As a result, he received the following series, where the frequency of the change of the leading types of activity is observed:

direct-emotional communication (infancy);

object-manipulative activity (early childhood);

role-playing game (preschooler);

educational activity (junior school student);

intimate-personal communication (younger teenager);

educational and professional activities (senior teenager).

Thus, in this age periodization, two indicators act as the main development criteria - the motivational-required sphere and the operational and technical capabilities of the child. The absence of definite temporal boundaries in this classification suggests that the author focused not on the metric, but on the topological characteristics of age development.

Periodizations covering the entire life cycle of a person include the classification of age periods adopted at one of the symposiums of the USSR Academy of Sciences in 1965 (Table 6).

Table 6

The periodization proposed by Birren includes the phases of life from infancy to old age. According to B. G. Ananiev, it is interesting because it takes into account modern historical trends in accelerating maturation during the period of growth and slowing down the aging process. According to this classification: youth - 12-17 years old, early maturity - 18-25 years old, maturity - 26-50 years old, late maturity - 51-75 years old, and old age - from 76 years old.

Eight stages of a person's life from birth to old age are described by E. Erickson, who drew attention to the development of the human "I" throughout life, to personality changes in relation to the social environment and to oneself, including both positive and negative aspects. The first stage (trust and distrust) is the first year of life. The second stage (independence and indecision) - 2-3 years. The third stage (enterprise and guilt) - 4-5 years. The fourth stage (skill and inferiority) - 6-11 years. Fifth stage (personal identification and confusion of roles) - 12-18 years. The sixth stage (intimacy and loneliness) is the beginning of maturity. The seventh stage (general humanity and self-absorption) is mature age and the eighth stage (wholeness and hopelessness) is old age. This classification uses metric and topological criteria. Moreover, with age, the importance of topological characteristics in assessing the psychological variability of a person increases. The classification of the German anthropologist G. Grimm is built purely qualitatively, without metric definitions of the duration of the phases of age development. In his opinion, numerical expressions for determining time limits are possible only for the first periods, meaning the increase in individual variability with age. This classification is of interest because it takes into account morphological and somatic changes, such an important indicator as a person's ability to work in different periods of his life. The most complete and detailed, covering the entire life cycle, is D. Bromley's age periodization. He considers human life as a set of five cycles: uterine, childhood, youth, adulthood and aging. Each of the cycles consists of a number of stages. The first cycle consists of 4 stages until birth. Since that time, development has been characterized by a change in the ways of orientation, behavior and communication in the external environment, the dynamics of the intellect, the emotional-volitional sphere, motivation, the social formation of the personality and professional activity. The second cycle - childhood - consists of three stages: infancy, preschool childhood and early school childhood, and covers 11-13 years of life. The cycle of adolescence consists of two stages: the stage of puberty (11-13-15 years) and late adolescence (16-21). The cycle of adulthood consists of four stages:

1) early adulthood (21–25 years);

2) average adulthood (26–40 years old);

3) late adulthood (41–55 years);

4) pre-retirement age (56–65 years). The aging cycle consists of three stages:

1) removal from affairs (66–70 years);

2) old age (71 years or more);

3) the last stage - painful old age and decrepitude. Periodizations differ in how broadly and how detailed

they present age-related changes in various aspects of the psyche and to what extent the metric and topological properties of the age-related development of a person are expressed. According to B. G. Ananiev, the most difficult thing is to determine the duration of developmental phases and critical points, its discrete moments, since one should take into account the heterochrony of functional and personality changes, as well as age and individual variability in changing historical conditions.

§ 15.2. EARLY CHILDHOOD

From the moment of birth, various mechanisms of mental activity begin to function in a child, which ensure his interaction with adults and with the environment and the satisfaction of his vital needs. A newborn is capable of perceiving effects on various sense organs in an elementary form. All analyzers from the first days of a child's life carry out an initial, elementary analysis of the effects of the environment. Newborns not only respond to a strong sound, but are able to distinguish sounds that differ by one octave. It was established in children the presence of color, as well as gustatory and olfactory sensitivity. There is information about the presence of other types of sensations. The most sensitive areas to touch are the lips, forehead and palms of the child. He may refuse milk, which is 1 ° C colder than usual. Children in the first 10 days of life prefer structural, complex, three-dimensional, moving objects. Small children can follow the object, localize it in space, compare objects with each other. Along with various forms of sensory activity, the newborn has a large set of postural and locomotor reflexes. All this contributes to the rapid adaptation of the child to new conditions of life and the creation of prerequisites for its further development. The emergence of individual experience, the establishment of various relationships and connections with the social environment based on the mechanism of temporary connections means the transition from a newborn at the end of the first month of life to a new, infantile, period of development.

Infant age from 1 month to 1 year is characterized by a high intensity of the processes of development of sensory and motor functions, the creation of the prerequisites for speech and social development in conditions of direct interaction between the child and adults. At this time, the environment is extremely important, the participation of adults not only in the physical, but also in the mental development of the child (creation of an enriched physical and speech environment, emotional communication, assistance in the development of his various movements, the act of grasping and locomotion, the creation of problem situations, etc.). P.). Mental development in infancy is characterized by the most pronounced intensity, not only in terms of pace, but also in the sense of new formations. At present, the stages of development of all types of motor skills (eye movements, the act of grasping, locomotion), the initial forms of thinking, the prerequisites for speech, and perceptual function have been established. On this rich and multi-qualitative basis, after a year of life and throughout the entire life cycle of a person, the social development of the psyche is carried out.

The next - pre-preschool - period - from 1 year to 3 years of life. The importance of these two years of life is due to the fact that at this time the child masters speech and the prerequisites are created for the formation of the personality and the subject of activity. The rapid development of speech is due to the fact that almost simultaneously the child begins to learn the phonetic structure of the language (from 11 months) and its vocabulary (from 10–12 months). By the end of preschool age, he begins to link individual words into sentences (from 1 year 10 months), which means a transition to inflectional speech. The formation of links between words and objects is directly dependent on the frequency, duration and nature of communication between adults and a child. On the basis of speech in the second year of life, he not only associates the word with a single object, but also begins to group objects according to the most striking external features, for example, by color. This means the appearance of the first stage in the development of the generalization function.

Preschool age is the initial stage in the formation of the regulatory function of speech. The inhibitory function of speech in its development lags behind its triggering function. A child under 3 years old cannot yet follow a complex instruction that requires a choice. He can only follow simple instructions from an adult. At this time, various basic forms of the psyche are actively developing: memory in the form of recognition, visual thinking, attention, perception, psychomotor. With age, the period between the perception of an object and its recognition lengthens. In the second year of life, the child recognizes close people and objects after a few weeks, in the third year - after a few months, and in the fourth - after a year after their perception.

At preschool age, various mental functions begin to take shape, such as the ability to generalize, transfer acquired experience to new conditions, the ability to establish connections and relationships and, in an elementary form, through active experimentation, solve specific problems using various objects as a means to achieve the goal. Speech and practical activity of the child play a significant role in the development of the thinking ability. The dominant function in pre-school age is perception, which develops intensively during this period and at the same time it determines the specifics of other mental forms that function at the visual-sensory level (memory, thinking).

Starting from 1 year 6 months, children successfully cope with the choice of simple shapes according to the model, such as a square, a triangle, a trapezoid. At 3 years old, children could visually correlate the shape and shape of the holes and then act correctly, for example, insert a certain type of key into the corresponding hole.

How actively a preschooler will be included in sensory-perceptual activity depends not only on the formation of perception itself, but also on other forms of the child's psyche. And here comes to the fore the organization by adults of the process of contemplation and experimentation, a wide and varied practical acquaintance of children with objects of the world around them. To stimulate the cognitive and practical activity of the child, emotional contacts with the mother are important. At 6 months, children show the same results in mental development, regardless of living conditions and upbringing. At the age of one year, children separated from their parents begin to lag behind in their mental development. In 3 years, the influence of the socio-economic factor also affects. Children from cultural, wealthy families show superior development compared to children from working families. Studies of mental deprivation in childhood have shown that the long-term separation of a child from his mother or another person who takes her place in the first years of life, as a rule, leads to a violation of the mental health of the child, leaving consequences throughout his further development.

Direct contacts with the mother in early childhood provide a whole range of positive influences on the child. An adult not only emotionally stimulates cognitive and practical activity, but also carries out the optimal organization of the environment, enriching it with toys and various objects. It acts as a source of social and emotional reinforcement for the activities of a small child. At the same time, he uses the dominant role of perception in order to effectively influence children's behavior. In communication and cooperation with adults, the child's communicative activity begins to manifest itself, which, in turn, affects the development of his cognitive functions, not only speech, but also attention, memory, and especially their arbitrary forms.

The formation of the subject of practical activity originates in preschool age. At this time, the child learns to use various household and play items (typewriter, spoon, cup), can perform sequential actions according to elementary instructions. During this period of life, the direct cooperation of the child with adults is especially important, which contributes to the formation of his independence and initiative.

In early childhood, the prerequisites for personality development are also created. The child begins to separate himself from other objects, stand out from the people around him, which leads to the emergence of initial forms of self-consciousness. The first stage in the real formation of the personality as an independent subject, standing out from the surrounding world, is associated with the mastery of one's own body, with the emergence of voluntary movements. These latter are developed in the process of formation of the first objective actions. By the age of 3, the child develops an idea of ​​himself, which is expressed in the transition from calling himself by name to using the pronouns “my”, “I”, etc. Considering the genesis of self-consciousness, B. G. Ananiev believed that the formation of one’s own “I » there is a huge leap in development, as there is a transition to separating oneself as a permanent whole from the current stream of changing actions. The main factors in the genesis of the child's self-awareness, in his opinion, are communication with adults, mastery of speech and objective activity. It should also be noted that the pre-preschool age is characterized by rapid and at the same time uneven rates of development of various mental functions. The development of attention is of great importance. Children with an undeveloped reaction to novelty also demonstrate lower scores in memory, thinking and speech. During this period of life, an arbitrary form of attention appears, which is observed during visual search according to the verbal instructions of an adult. If at 12 months this form is still absent, then at 23 months it is already present in 90% of children. At this time, in terms of growth rates, the leading one is spatial visual memory, which is ahead of figurative and verbal memory in its development.

By the end of the second year of life, an arbitrary form of memorizing words appears. The ability to classify objects according to shape and color is manifested in most children in the second half of the second year of life. At preschool age, the speech function is intensively formed. In conditions of an impoverished social environment and insufficient communication between adults and children, precisely those functions that are basic for the social development of the psyche turn out to be underdeveloped. The study compared the mental functions of children aged 23–25 months raised in a family and in a children's home. The greatest differences were found in the development of speech, voluntary attention, classification by form and auditory memory, and the smallest differences were found in the development of involuntary forms of attention and classification by color.

Thus, by the age of 3, the necessary prerequisites are created for the transition to the next, preschool period. In early childhood, speech function, motor skills and objective actions are intensively formed. A variety of cognitive functions in their original forms (sensorics, perception, memory, thinking, attention) are also rapidly developing. At the same time, the child begins to develop communicative properties, interest in people, sociability, imitation, primary forms of self-consciousness are formed.

Mental development in early childhood and the variety of its forms and manifestations depend on how much the child is included in communication with adults and how actively he manifests himself in objective and cognitive activities.

§ 15.3. THE PERIOD OF PRESCHOOL CHILDHOOD

Preschool age is a period of further intensive formation of the psyche, the emergence of various qualitative formations both in the development of psychophysiological functions and in the personal sphere. New high-quality education occurs due to many factors: speech and communication with adults and peers, various forms of cognition and inclusion in various types of activities (playing, productive, household). All this contributes to a better adaptation of the child to social conditions and the requirements of life. At the same time, the elementary forms of the psyche, sensorics and perception continue to develop.

Two contradictory tendencies are observed in the development of the basic properties of perception. On the one hand, there is an increase in integrity, and on the other hand, the detailing and structure of the perceptual image is manifested. By the end of preschool age, the ability to isolate the shape of an object appears. By the age of 6, children begin to cope with the task of laying out the outline of a figure, such as a mushroom, at home without errors. For younger children, the solution to this problem is still practically inaccessible. By filming the movement of the child's eyes in the experiments of V.P. Zinchenko, it was found that children at the age of 3 cannot yet fix the contour of planar figures. The movements of their eyes are carried out “inside” the figures with a small number of fixations (1–2 movements per second). Only at the age of 6 does a thorough acquaintance with the figure take place and eye movements follow along its entire contour. However, already at the age of 3, children are able to follow the pointer along the contour, which indicates a high learning ability at this age. The ability of children to select objects along the contour means the formation of the integrity of perception. From the age of 5-6, there comes a turning point in the development of such a property of perception as structure. This is expressed in the fact that children are able to build a figure from its individual parts, to single out and correlate structural elements in complex objects. Children successfully solve problems by choosing not only simple, but also complex multi-component figures according to the model. At preschool age, social perceptual standards are also assimilated in the form of knowledge of geometric figures, tempered musical structure.

The leading form of the psyche at this time is the representation, which is intensively developed in various types of playful and productive activities (drawing, modeling, design, role-playing, story games). Representations leave an imprint on the entire process of mental development. Various forms of the psyche are most successfully formed if they are associated with secondary images, that is, with representations. Therefore, such forms of the psyche as imagination, figurative memory and visual-figurative thinking are rapidly developing.

Children's cognition of various properties and connections of things occurs in the process of operating with the images of these things. Not only various mental functions, but also the child's speech, its development during this period are mainly associated with ideas. The understanding of speech by children largely depends on the content of those ideas that arise in them in the process of its perception. The development of mental functions in preschool age is complicated by the fact that in the process of communication, cognitive and practical activity, social forms of the psyche are actively formed, not only in the perceptual sphere, but also in the field of memory (verbal memory, arbitrary memorization of words and objects). By the end of preschool age, verbal-logical thinking appears. Preschool age is the initial stage in the formation of the subject of cognitive and practical activity.

This period of life is extremely important in terms of the genesis and formation of social forms of the psyche and moral behavior. The predominance of topics related to the image of a person in the work of a preschooler indicates his primary orientation towards the social environment. This creates a broad basis for the formation of primary forms of socially significant qualities. By the end of preschool age, there is a transition from an emotional direct relationship to the outside world to relationships that are built on the basis of the assimilation of moral assessments, rules and norms of behavior. The formation of moral concepts in preschool age occurs in various ways. When asked what kindness, courage, justice are, children either used specific cases of behavior or gave the general meaning of the concept. Answers in the general form in children of 4 years old were 32%, and 7 years old - 54%. Thus, in communicating with adults, the child often learns moral concepts in a categorical form, gradually clarifying and filling them with specific content, which speeds up the process of their formation and at the same time creates the danger of their formal assimilation. Therefore, it is important that the child learns to apply them in life in relation to himself and others. This is essential, first of all, for the formation of his personality traits. At the same time, socially significant standards of behavior are important, which become literary heroes and people directly surrounding the child. Of particular importance as behavioral standards for a preschooler are the characters of fairy tales, where positive and negative character traits are emphasized in a concrete, figurative, accessible form, which facilitates the child's initial orientation in the complex structure of a person's personal properties. Personality develops in the process of real interaction of the child with the world, including the social environment, and through the assimilation by him of the moral criteria that regulate his behavior. This process is controlled by adults who contribute to the selection and training of socially significant properties. The independence of the child begins to manifest itself in the case when he applies moral assessments to himself and others and regulates his behavior on this basis. This means that at this age such a complex personality trait as self-awareness develops. B. G. Ananiev singled out the formation of self-esteem in the genesis of self-consciousness. The adequacy of the child's value judgments is determined by the constant evaluative activity of parents, as well as educators in connection with the implementation of the rules of behavior for children in a group in various activities (games, duty, classes). Already at the age of 3-4 there are children who are able to independently assess some of their capabilities and correctly predict the results of their actions based on their own experience (for example, the distance of the jump). It should be noted that the influence of parents' assessments on the preschooler's self-esteem depends on the child's understanding of the competence of the mother and father and the style of upbringing, on the nature of relationships in the family. Children accept and assimilate the assessments of the parent, who for them is a significant person and the bearer of standards of behavior.

By the age of 5, children have a certain position in the group, they are differentiated by sociometric status. At the same time, the preferences that the child has for his peers in play activities, in the classroom, and in the performance of labor assignments are relatively stable. The selectivity of choice is associated with the formation of a motivational sphere and various personal properties at preschool age. The main motive that encourages children to unite is satisfaction with the process of playing communication. In second place is the orientation towards the positive qualities of the chosen one, which are manifested in communication (cheerful, kind, honest, etc.). Later, in children of 6–7 years old, their ability to perform any particular activity also acts as a motive for choosing a partner. Orientation to personal characteristics that are formed outside of direct play communication, in various activities, in communication with adults (industriousness, obedience, ability to draw, sing), indicates different sources of formation of motives that determine relationships in children's groups.

Preschool age is the initial stage in the formation of the subject of activity. The transition to the preschool period is marked by the fact that the child is no longer satisfied with simple manipulative actions that he mastered in previous years. Goal-setting, the volitional component of the subject of activity is formed. Concentration and consistency in actions, self-assessment of one's actions and the result obtained are manifested. Under the influence of assessments and control of an adult, an older preschooler begins to notice mistakes in his own activities and in the work of others, and at the same time highlight role models. At preschool age, both general, mental and special abilities for visual, musical, choreographic and other activities are formed. Their originality lies in the fact that they are based on the development of different forms of representations (visual, auditory, etc.).

The emerging various kinds of qualitative formations, such as personal properties, psychological structures of the subject of activity, communication and cognition, the intensive process of socialization of the natural forms of the psyche, its psychophysiological functions, create real prerequisites for the transition to the school period of life. Adults largely determine the originality and complexity of the mental development of a preschooler, forming his psychological readiness for schooling.

§ 15.4. SCHOOL AND YOUTH PERIODS

The main activity of school childhood is educational, during which the child not only masters the skills and methods of obtaining knowledge, but also enriches himself with new meanings, motives and needs, masters the skills of social relationships.

School ontogeny covers the following age periods: junior school age - 7-10 years; junior teenage - 11-13 years old; senior teenage - 14-15 years; adolescence - 16-18 years. Each of these periods of development is characterized by its own characteristics.

One of the most difficult periods of school ontogenesis is adolescence, which is otherwise called the transitional period, as it is characterized by the transition from childhood to adolescence, from immaturity to maturity.

Adolescence is a period of rapid and uneven growth and development of the body, when there is an intensive growth of the body, the muscular apparatus is being improved, and the process of ossification of the skeleton is underway. Inconsistency, uneven development of the heart and blood vessels, as well as increased activity of the endocrine glands often lead to some temporary circulatory disorders, increased blood pressure, cardiac tension in adolescents, as well as an increase in their excitability, which can be expressed in irritability, fatigue, dizziness and heartbeat. The nervous system of an adolescent is not always able to withstand strong or long-acting stimuli, and under their influence it often passes into a state of inhibition or, conversely, strong excitation.

The central factor in physical development in adolescence is puberty, which has a significant impact on the functioning of internal organs.

Sexual desire (often unconscious) and new experiences, desires and thoughts associated with it appear.

Features of physical development in adolescence determine the most important role during this period of the correct mode of life, in particular, the mode of work, rest, sleep and nutrition, physical education and sports.

A distinctive feature of mental development is that it has a progressive and at the same time contradictory hetero-chronic character throughout the entire school period. Psychophysiological functional development is at this time one of the main directions of mental evolution.

Learning activity is provided by the development of primary and secondary properties of an individual organization. The strength of the nervous system increases in relation to the processes of excitation and inhibition in the period from 8-10 to 18 years. Sensory sensitivity increases significantly in the process of development, for example, light-discriminating sensitivity increases from class 1 to class 5 by 160%.

The functions of attention, memory, thinking become more complicated. At the first stage (8-10 years), the progressive nature of the development of attention is noted, which is ensured by the growth of all its aspects (volume, stability, selectivity, switching). At the age of 10–13 years, there is a slowdown in growth, function and multidirectional changes in its individual aspects. At the age of 13–16, there is an accelerated and unidirectional growth of attention, especially its stability. Throughout school ontogenesis, the dynamics of the productivity of individual types of memory is oscillatory, curvilinear in nature. At the same time, the highest level of productivity of figurative memory is achieved at 8-11 years old, and verbal - at 16 years old (Rybalko E.F.).

The development of the intellectual sphere is the central link in development at school age. “Thinking is that function, the most intensive development of which is one of the most characteristic features of school age. Neither in sensations, nor in mnemonic abilities is there such a huge difference between a child of 6–7 years old and a young man of 17–18 years old, which exists in their thinking,” wrote P. P. Bolonsky. Schooling has a decisive influence on mental development.

Noting quantitative and qualitative changes in the development of cognitive functions and intellect in children, J. Piaget determined that as children grow up and go to school, they develop the ability to perform many previously inaccessible mental operations. At the age of 7-8 years, the child's thinking is limited to problems relating to specific, real objects and operations with them. Only from the age of 11-12 is the ability to think logically about abstract, abstract problems formed, there is a need to check the correctness of one's thoughts, accept the point of view of another person, mentally take into account and correlate several signs or characteristics of an object at the same time. The so-called "reversibility" of thinking appears, that is, the ability to change the direction of thought, returning to the original state of an object. Thanks to this, the child understands, for example, that addition is the opposite of subtraction, and multiplication is the opposite of division. Adolescents develop scientific thinking skills, thanks to which they talk about the past, present and future, put forward hypotheses, assumptions, and make forecasts. Young men develop an inclination towards general theories, formulas, etc. The tendency to theorize becomes, in a certain sense, an age-related feature. They create their own theories of politics, philosophy, formulas for happiness and love. A feature of the youthful psyche associated with formal operational thinking is a change in the relationship between the categories of possibility and reality. Mastering logical thinking inevitably gives rise to intellectual experimentation, a kind of game of concepts, formulas, etc. obey systems, not systems of reality.

The lack of formation of the mental sphere, the inability to make comparisons, establish cause-and-effect relationships, and draw conclusions make it difficult for the student to learn, require a huge amount of mechanical memory, perseverance, and make the learning process uninteresting.

The intellectual development of a person is determined by the level of maturity of functions and mental activity, as well as the conditions and content of training. The conditions of school specialized education impose a significant influence on the dynamics of intellectual functions. The development of intellectual potential has a negative effect on the reduction of requirements for students, the facilitation of training programs, training in the absence of the formation of life and professional goals, as this creates the prerequisites for a slow, disharmonious type of intellectual development.

The development of the intellectual sphere has an impact on the development of other aspects of the child's psyche. In the mental appearance of a teenager, “... the activity of analyzing thoughts, a tendency to reasoning and special emotionality, impressionability are most often combined. Such a combination of features of the “thinking” and “artistic” type characterizes the unique originality of age and, apparently, is a guarantee of multilateral development in the future” (N. S. Leites).

During the school period, the motives of educational activity develop. Primary school students in the structure of motivation are dominated by the motive of striving for the position of a schoolchild, in the middle grades (grades 5-8) the desire to take a certain place in the peer group prevails, in the senior grades (grades 10-11) the most significant is the orientation towards the future, and the leading motive is the motive of teaching for the sake of a future life perspective. At the same time, as noted by I. V. Dubrovina et al., many schoolchildren have an unformed cognitive need as a need to acquire and assimilate new knowledge. And this, in turn, leads to the fact that teaching is perceived by schoolchildren as an unpleasant duty, giving rise to negative emotions and persistent school anxiety, which is noted on average in 20% of schoolchildren.

If in the younger adolescence the most intense changes occur in physical development, then in the older adolescence and youth, the personality of the child develops most rapidly.

The process of personality development is characterized by two opposite tendencies: on the one hand, ever closer interindividual contacts are being established, the focus on the group is increasing, on the other hand, there is an increase in independence, the complication of the inner world and the formation of personal properties.

Adolescent crises are associated with emerging neoplasms, among which the central place is occupied by a “sense of adulthood” and the emergence of a new level of self-awareness.

The characteristic feature of a 10-15-year-old child is manifested in a heightened desire to establish himself in society, to achieve recognition of his rights and opportunities from adults. At the first stage, the desire for recognition of the fact of their growing up is specific for children. Moreover, for some younger adolescents, it is expressed in the desire only to assert their right to be like adults, to achieve recognition of their adulthood (at the level, for example, “I can dress the way I want”). For other children, the desire for adulthood consists in a thirst for recognition of their new capabilities, for others, in the desire to participate in various activities on an equal basis with adults (Feldshtein D.I.).

A reassessment of their increased capabilities is determined by the desire of adolescents for a certain independence and self-sufficiency, painful pride and resentment. Increased criticality towards adults, a sharp reaction to the attempts of others to belittle their dignity, belittle their adulthood, underestimate their legal capabilities are the causes of frequent conflicts in adolescence.

Orientation towards communication with peers often manifests itself in the fear of being rejected by them. The emotional well-being of a teenager more and more begins to depend on the place that he occupies in the team, begins to be determined primarily by the attitude and assessments of his comrades. A grouping tendency appears, which causes a tendency to form groups, “brotherhoods”, a readiness to recklessly follow the leader.

Intensively formed moral concepts, ideas, beliefs, principles that teenagers begin to be guided in their behavior. Often they form a system of their own requirements and norms that do not coincide with the requirements of adults.

One of the most important moments in the formation of a teenager's personality is the development of self-awareness, self-esteem (SE); adolescents develop an interest in themselves, in the qualities of their personality, a need to compare themselves with others, evaluate themselves, understand their feelings and experiences.

Self-esteem is formed under the influence of other people's assessments, comparing oneself with others, the most important role in its formation is the success of the activity.

If at primary school age SA is inseparable from the assessment of others, then significant changes occur in adolescence: a reorientation from external assessments to assessments of oneself. The content of SO becomes more complicated: it includes moral manifestations, attitudes towards others, and one's own capabilities. The perception of external assessments and self-perception are aggravated, the assessment of one's own qualities becomes an urgent task for a teenager. In adolescence, the development of SO goes in the direction of increasing its integrity and integration, on the one hand, and differentiation, on the other. With age, knowing himself, a person, as in a mirror, peers into another person. Turning to other people, comparing oneself with them is a necessary general prerequisite for knowing oneself. Thus, there is a kind of transfer of various personality traits, noticed in another, to oneself.

As shown by numerous studies, the presence of positive self-esteem, self-respect is a necessary condition for the normal development of the individual. At the same time, the regulatory role of self-esteem is steadily increasing from primary school age to adolescence and youth. The discrepancy between the self-esteem of a teenager and his claims leads to acute affective experiences, to exaggerated and inadequate reactions, the manifestation of resentment, aggressiveness, distrust, stubbornness.

Trends in the development of characterological features are that from 12 to 17 years of age, indicators of sociability, ease in communicating with people, dominance, perseverance, competitiveness increase markedly, at the same time, there is a tendency to reduce impulsivity, excitability. At this age, certain properties of character are especially sharply manifested and accentuated. Such accentuations, while not being pathological in themselves, nevertheless increase the possibility of mental trauma and deviations from the norms of behavior. However, emotional difficulties and the painful course of adolescence are not a universal property of youth.

The crisis of adolescence proceeds much easier if the student during this period has relatively permanent personal interests or any other stable motives for behavior. Personal interests, in contrast to episodic ones, are characterized by their "unsaturation"; the more they are satisfied, the more stable and tense they become. Such, for example, are cognitive interests, aesthetic, etc. The satisfaction of such interests is associated with the setting of ever new goals. The presence of stable personal interests in a teenager makes him purposeful, internally more collected and organized.

The transitional critical period ends with the emergence of a special personal formation, which can be designated by the term "self-determination", it is characterized by awareness of oneself as a member of society and one's purpose in life. In the transition from adolescence to early adolescence, the internal position changes dramatically, aspiration for the future becomes the main focus of the personality, the focus of the interests and plans of the young man is the problem of choosing a profession, a further life path. In essence, we are talking about the formation at this age stage of the most complex, highest goal-setting mechanism, which is expressed in the existence of a certain “plan”, a life plan in a person.

The internal position of the senior student is characterized by a special attitude to the future, perception, evaluation of the present from the point of view of the future. The main content of this age is self-determination, and above all professional.

Considering the main stages of becoming a professional, E. A. Klimov specifically highlights the stage of “option” (from Latin optatio – desire, choice), when a person makes a fundamental decision about choosing the path of professional development. The option stage covers the period from 11–12 to 14–18 years (Klimov E. A.).

The basis for an adequate professional choice is the formation of cognitive interests and professional orientation of the individual. The study of the development of interests allows us to distinguish 4 stages in the process of their formation. At the first stage, at the age of 12–13 years, interests are characterized by high variability, are poorly integrated, are not associated with the structure of individual psychological characteristics, and are predominantly cognitive. At the second stage, at the age of 14–15, there is a tendency towards greater formation of interests, their integration, inclusion in the general structure of individual and personal characteristics. At the third stage, at the age of 16–17 years, the integration of interests increases and, at the same time, their differentiation in accordance with gender, the unification of cognitive and professional interests takes place, and the interrelationships of interests with individual psychological properties increase. At the fourth stage - the stage of initial professionalization - there is a narrowing of cognitive interests, determined by the formed professional orientation and choice of profession (Golovey L. A.).

Interests that have reached a high level of development are the basis for the formation of a professional orientation of an individual and an adequate, mature professional choice. The professional orientation is based on individual psychological characteristics, the system of personality potentials and has a fairly pronounced gender specificity: boys are more likely to have a technical orientation, while girls have a social and artistic orientation.

The process of professional self-determination goes through a number of stages. The first stage is a children's game, during which the child assumes various professional roles and "loses" individual elements of the behavior associated with them. The second stage is a teenage fantasy, when a teenager sees himself in his dreams as a representative of an attractive profession for him. The third stage, covering the entire adolescence and most of adolescence, is the preliminary choice of a profession. Various activities are sorted and evaluated first in terms of the teenager's interests ("I love history, I'll be a historian!"), then in terms of his abilities ("I'm good at math, can I do it?") and, finally, from the point of view of his value system (“I want to help the sick, I will become a doctor”). The fourth stage - practical decision-making, the actual choice of profession - includes two main components: determining the level of qualification of future work, the volume and duration of the necessary preparation for it, i.e., the choice of a specific specialty. However, judging by the data of sociologists, the orientation toward entering a university is formed earlier than the choice of a specific specialty matures.

In addition to interests, abilities and value orientations, an important role in decision-making is played by the assessment of one's objective capabilities - the material conditions of the family, the level of training, the state of health, etc.

The most important psychological prerequisites for successful professional self-determination are the formed intellectual potential, adequate self-esteem, emotional maturity and self-regulation of the individual.

In the conditions of modern school education, when most schoolchildren must choose their future profession or profile of education at the age of 13–14, adolescents often turn out to be not ready for independent choice and show low activity in professional self-determination. This indicates the need to introduce professional orientation and psychological counseling in schools and other educational institutions when choosing a profession.

§ 15.5. ACMEOLOGICAL PERIOD OF DEVELOPMENT. ADULT PERIOD

In developmental psychology, adulthood has traditionally been viewed as a stable period. The French psychologist E. Claparede described maturity as a state of mental "petrification", when the development process stops. However, later it was shown that the process of human development does not end with the onset of adulthood, at all stages of which sensitive and critical moments are distinguished, the nature of the psychophysiological development of maturity is heterogeneous and contradictory. The term "acmeology" was proposed by N. N. Rybnikov in 1928 to designate the period of maturity as the most productive, creative period of a person's life (acme - the highest point, flourishing, maturity, the best time). This period covers the age from 18 to 55–60 years and differs from the youthful period primarily in that general somatic development and puberty are completed in it, physical development reaches its optimum, it is characterized by the highest level of intellectual, creative, professional achievements.

The largest systematic comprehensive studies of this period of human life were organized and conducted under the guidance of Academician B. G. Ananiev at St. Petersburg State University and the Institute of Adult Education of the Russian Academy of Education.

The structure of the psychophysiological development of adults combines periods of ups and downs and stabilization of functions. At the same time, the stationary state is relatively rare (in 14% of cases). The contradictory structure of development characterizes both the most complex formations: intellect, logical and mnemonic functions, and the most elementary processes, including heat generation, metabolism, and multilevel characteristics of psychomotor.

In the early stages of maturity at the age of 18–20, optima (points of the highest rise) of visual, auditory, and kinesthetic sensitivity are noted. The volume of the visual field reaches its maximum at 20-29 years. Age-related variability of sensitivity depends on the professional activity of a person.

For example, people who deal with fine details experience a faster decrease in visual acuity than those whose professional activities are related to the perception of distant objects.

A study of the function of attention showed that the volume, switching and selectivity of attention increase gradually from 18 to 33 years old, after 34 years they begin to gradually decrease, at the same time, the stability and concentration of attention change slightly throughout maturity. The highest indicators of short-term verbal memory were noted at the age of 18–30 years, and the period of decline was at the age of 33–40 years. Long-term verbal memory is characterized by the greatest constancy at the age of 18 to 35 years and a decrease in the level of development - from 36 to 40 years. Figurative memory undergoes the least age-related changes.

It should be noted that specially organized memory exercise, when memorization becomes a special type of intellectual activity, increases the level of memory development not only in children, but also in adults.

Thus, the development of psychophysiological functions in the period of adulthood is complex and contradictory, which reflects ontogenetic patterns and the influence of labor activity, practical experience of a person.

As studies by B. G. Ananyev have shown, two phases are distinguished in the process of ontogenetic development. The first phase is characterized by a general frontal progress of functions (in youth, youth and early middle age). In the second phase, the evolution of functions is accompanied by their specialization in relation to a particular activity. This second peak of functional development is reached in later periods of maturity. If in the first phase of development the functional ontogenetic mechanism acts as the main mechanism, then in the second phase these are operational mechanisms, and the duration of this phase is determined by the degree of activity of a person as a subject and personality (Ananiev B.G.). Achieving high levels of development in adulthood is thus possible due to the fact that mental functions are under conditions of optimal load, increased motivation, and operational transformations. So, for example, in persons of driving professions, visual acuity, field of vision, and the eye remained intact until retirement age due to their involvement in professional activities.

Intelligence is of paramount importance in the structure of the development of the period of maturity. Most researchers cite relatively early dates for the appearance of optimum intellectual development and their gradual decline with age. So, Fulds and Raven believe that if the level of development of the logical ability of 20-year-olds is taken as 100%, then at 30 years old it will be 96%, at 40 years old - 87, at 50 years old - 80, and at 60 years old - 75% . The development of intelligence is determined by two factors: internal and external. The internal factor is giftedness. In the more gifted, the intellectual process is longer and involution occurs later than in the less gifted. The external factor is education, which resists aging and slows down the process of involution of mental functions. Verbal-logical functions, reaching an optimum in early youth, can remain at a fairly high level for a long period, declining by the age of 60. The use of the longitudinal method showed a sharp increase in the indices from 18 to 50 years old and their slight decrease by the age of 60 in creative people.

E. I. Stepanova identifies 3 macro-periods in the intellectual development of adults: I period - from 18 to 25 years old, II - 26-35 years old, III - 36-40 years old. These age macroperiods are distinguished by different rates of development of memory, thinking, attention and intelligence in general. The greatest variability of intelligence was noted in macroperiod I, in II and III there is relative stability with a pronounced rise in verbal intelligence, which can be explained by the influence of knowledge accumulated by a person. In general, in the entire range of adulthood from 17 to 50 years old, there is an uneven development of verbal and non-verbal components of intelligence. Scientific data convincingly show that the learning process itself is a factor in optimizing intellectual development. In persons with higher education and with constant mental training, the level of high intelligence is maintained throughout the entire range of adulthood; in the process of adult development, there is an increase in learning ability.

In the period of maturity, optima are also noted in the creative activity of a person. The optimal age moments of scientific creativity are known, which fall at the age of 35–45 years. However, in different types of activity they do not coincide. In choreography, such moments are celebrated between 20-25 years old, in music and poetry - between 30-35 years old, in philosophy, science, politics - at 40-55 years old. The creative activity of scientists of different specialties during maturity has a number of alternating periods of optima and declines (Table 7).

Table 7

Ontogenetic dynamics of creative activity of scientists

Thus, on the example of creative activity, the continuity of the development of the potentials of a mature person can be traced, and the period of adulthood manifests itself as the most productive in relation to the highest achievements of the intellect.

In the period of early adulthood, their own way of life is built, professional roles are mastered, and they are included in all types of social activity. In the period of middle adulthood, the consolidation of social and professional roles begins. Late adulthood is characterized by the further establishment of social and special roles by occupation and at the same time their restructuring, the dominance of some of them and the weakening of others; the structure of family relations (the departure of children from the family) and the way of life are changing. The development of status occurs up to the pre-retirement age, when the peak of the most common social achievements is noted - position in society, authority.

Mature age can be called the age of a person's practical, professional life. The setting of life tasks is based on the principles and ideals already defined at the previous stage, the life plans of a person. Personal development during this period is closely related to professional and family roles and can be briefly described as follows. Early adulthood is the period of "entry" into the profession, social and professional adaptation, awareness of civil rights and obligations, social responsibility; family education, the establishment of intra-family relations, the solution of domestic and budgetary problems, the development of a style of raising children.

The normative crisis of 30–33 years is due to a mismatch between a person's life plans and real opportunities. A person filters out the insignificant, reconsiders the value system. The unwillingness to make changes in the system of values ​​leads to an increase in contradictions within the personality.

The stable period of 33-40 years is characterized by the fact that at this age a person does what he wants most successfully, he has goals that he sets and achieves. A person shows literacy, competence in the chosen profession and requires recognition. 40-45 years - mid-life crisis; this age is a crisis for many, as there is a growing contradiction between the integrity of the worldview and the unilinear development. Man loses the meaning of life. To get out of the crisis, it is necessary to acquire a new meaning - in universal human values, in the development of interest in the future, in new generations. If a person continues to focus on himself, his needs, then this will lead him to go into illness, to new crises.

The period from 45 to 50 years is stable, a person reaches real maturity, he balances his needs well with the needs of others, he finds compassion and agreement with other people. For many, this period is a period of leadership and qualification.

The difficulties that accompany certain stages of life are overcome by the desire of the person himself to develop, become more mature and responsible. A mature personality in the course of development more and more independently chooses or changes the external situation of its development and, thanks to this, changes itself.

Thus, in the period of adulthood, there is an increase in the social development of the individual, his inclusion in various spheres of social relations and activities. The process of personality development in this case largely depends on the level of social activity and the degree of productivity of the personality itself.

§ 15.6. GERONTOGENESIS

In the periodization of gerontogenesis, three gradations are distinguished: old age: for men - 60-74 years, for women - 55-74 years, old age - 75-90 years, centenarians - 90 years and older. Aging in late ontogenesis occurs in various structures of a person as an individual, personality, subject of activity. The specifics of aging at various levels of its individual organization, where there is a decrease in the intensity of carbohydrate, fat and protein metabolism, a decrease in the ability of cells to carry out redox processes, has been studied in most detail. This is also facilitated by the growth of connective tissue in various functional systems, in skeletal muscles, blood vessels and other organs. At the same time, scientists come to understand aging as an internally contradictory process, characterized not only by a decrease, but also by a decrease in the activity of the body, due to the action of the law of heterochrony, i.e., the multidirectional changes occurring in individual functional systems. Of particular importance are the evolutionary-involutionary processes occurring in the central nervous system. During the period of gerontogenesis, the processes of excitation and inhibition are weakened. However, in this case, there is no frontal deterioration in the functions of the nervous system. In older people, the defensive conditioned reflex is the most preserved. The food reflex in them is developed more slowly than in the groups of young people, and it was not possible to obtain an orienting-exploratory reflex in older subjects after 65–70 years of age. Heterochrony in the central nervous system is also manifested in the fact that with age, primarily the inhibitory process and the mobility of nervous processes age, and the closing function suffers relatively less. Along with the increase in multidirectionality and inconsistency in the period of gerontogenesis, there is a clearly pronounced individualization of age-related variability of function. An associative experiment was conducted with subjects aged 40 to 90 years. In the group of 40–60 years, the latent period of speech reactions was from 1.2 to 7.2 s, in 60–70 year olds it ranged from 1.2 to 12 s, in the older group of 70–80 years it varied from 1, 2 to 15 s, and persons aged 80–90 years had a latent period from 1.3 to 25 s. Comparison of the obtained data with the average available for young age (1.2 s) demonstrates the extreme degree of individual differences in the elderly and senile age. There are subjects who, up to a very old age, are distinguished by a high preservation of the indicator of the latent time of speech reaction and other phenomena of the psyche, while in others this and other indicators change to a great extent with age.

During the period of gerontogenesis, there is an adaptation to new conditions of life and an increase in various ways of the biological activity of various structures of the body, ensuring its performance after the completion of the reproductive period. One of the ways of adaptation is the mobilization of the body's reserve capabilities. Along with the weakening of the intensity of oxidative processes, with age, the backup energy generation pathway, glycolysis, is activated, and the activity of many enzymes increases. Another way of restructuring the body is expressed in the formation of new adaptive mechanisms. Along with destructive changes (deposition of fats, salts), the pigment lipofuscin accumulates, which has a high rate of oxygen consumption, and the number of nuclei in many cells of the liver, kidneys, heart, skeletal muscles, nervous system also increases, which leads to an improvement in their metabolic processes. The appearance in old age of giant mitochondria, which are the main mechanisms of energy accumulation, has also been shown. Thus, during the aging period, overcoming destructive phenomena and increasing the activity of various body structures is carried out in various ways: by reserving, intensifying and compensating existing structural formations, as well as by forming high-quality formations that contribute to maintaining human performance. During the period of gerontogenesis, the role of the personal factor in creating a healthy lifestyle increases. In the conscious regulation of behavior aimed at the preservation of the individual organization and its further development, an important role is played by the emotional sphere, psychomotor and speech activity, which are integral characteristics of the human psyche. The data obtained in the study of physical inactivity demonstrate the variety of connections between the motor apparatus and various body systems. At the same time, the blood supply to the brain and heart is disturbed, focal destruction, oxygen starvation are observed in the organs, the intensity of oxidative processes in the heart and skeletal muscles decreases. A certain training system can optimize the functions of respiration, blood circulation and muscle performance in the elderly. The complex nature of the impact of emotionally significant stimuli on a person is evidenced by data on the dependence of life expectancy on the effects of prolonged stress. B. G. Ananiev attached great importance to the speech factor, which contributes to the safety of a person. He wrote that speech and thought functions resist the aging process and themselves undergo involutional shifts much later than all other psychophysiological functions. During the period of gerontogenesis, not only in the somatic organization, but also at the level of psychological functions, the inconsistency, unevenness and heterochrony of their age dynamics increase. This is expressed in the fact that the deterioration of the auditory analyzer with age is selective, due to both the historical nature of man and the protective functions of the body. In the high-frequency range (4000-16,000 Hz), after 40 years, there is a significant decrease in loudness sensitivity, in which its declines alternate with moments of rise. In the medium frequency range, where speech sounds are located, the deterioration of loudness sensitivity in the period of 20–60 years occurs to an insignificant degree, but low-frequency sounds (32–200 Hz) - noises, rustles retain their signal value in late ontogenesis. The decrease in different types of color sensitivity at the age of 25–80 also occurs at an unequal rate (data from A. Smith). Sensitivity to yellow after 50 years practically does not change, and to green it decreases at a slower pace. On the contrary, a significant weakening of the sensory response with age takes place to red and blue colors, i.e., to the extreme, short- and long-wavelength parts of the spectrum. At the same time, the visual function and sensory field of vision, according to our data, are characterized by a fairly high safety up to 70 years. All this testifies to the importance of these functions throughout a person's life, up to the period of aging.

During the period of gerontogenesis, heterochrony is also observed in the development of other mental functions. At the age of 70–90, mechanical imprinting suffers especially. Logical, verbal memory is best preserved. Semantic connections are the basis for the strength of memory at an older age. Based on the study of the English gerontologist D. B. Bromley, B. G. Ananiev wrote that in the process of gerontogenesis, the opposite course of development of verbal (awareness, vocabulary) and non-verbal (practical intelligence) functions is especially noteworthy. The decrease in non-verbal functions becomes pronounced by the age of 40. Meanwhile, it is precisely from this period that verbal functions progress most intensively, reaching a high level at 40–70 years. The preservation and further development of mental functions during the period of gerontogenesis is significantly influenced by professional activity and education. With a high level of education, there is no decline in verbal functions until old age. The level of education is closely related to the speed of speech, erudition and logical thinking. An important factor in the viability of an elderly person is his occupation. Persons of retirement age are characterized by a high preservation of those functions that were actively included in their professional activities. Thus, according to M. D. Aleksandrova, many non-verbal functions did not change with age among older engineers, and old accountants performed tests for the speed and accuracy of arithmetic operations as well as young ones. Visual acuity and field of vision remain at a high level until old age in drivers, sailors, and pilots. Meanwhile, in persons whose professional activity is based on the perception of near, not far space (mechanics, draftsmen, seamstresses), visual acuity can significantly decrease with age.

In late ontogenesis, the role of the individual, his social status and his inclusion in the system of social relations is enhanced, provided that the person's ability to work as a subject of various types of activity is preserved. Of particular importance as a factor opposing the involution of a person is his creative activity. Outstanding scientists and artists maintained high efficiency not only in old age, but also in old age. IP Pavlov created "Twenty Years of Experience" at the age of 73, and "Lectures on the work of the cerebral hemispheres" - at 77 years old. Leo Tolstoy wrote "Sunday" at the age of 71, and "Hadji Murat" at the age of 76. Michelangelo, Claude Monet, O. Renoir, S. Voltaire, B. Shaw, V. Goethe and many others were distinguished by high creative potential in the later years of their lives. Among the characteristic features of creative people is the breadth and diversity of their interests. The activity of creative individuals goes beyond their family and narrow professional interests and is expressed in their participation in pedagogical, social and other activities. In the activities of R. Tagore (1861–1941), an Indian writer and public figure, there is a pronounced variety of genres. He wrote poetry, plays, novels, novellas and short stories. In addition, he was a teacher, art critic, politician. After 60 years, he began to paint and created a number of wonderful canvases. Three peaks stand out in his literary work: 34, 49 and 69 years. On the whole, the work of R. Tagore is characterized by diversity, the search for something new, a huge capacity for work, dynamism and the absence of stereotypes of thinking.

Johann Sebastian Bach (1685-1750) also showed exceptional diversity in his work. He wrote sacred, orchestral, chamber, dance music, composed works for organ and choir, organ and solo singing, clavier, violin and orchestra. He composed fugues, sonatas, preludes, cantatas, chorales, concertos. In his later years, Bach was engaged in pedagogical and literary activities, wrote about music, and acted as a musicologist. An important feature of older people involved in creativity is strongly expressed activity motives, purposefulness and focus on the implementation and implementation of their plans and ideas in practice. Highly developed self-organization and criticality in relation to the results of their work, flexibility of mind are also inherent in a creative person throughout life up to the period of gerontogenesis. Direct interest in the process of creativity converges with the involvement of the individual in the life of society, which determines the personal meaning of creativity itself. The larger the personality, the more pronounced its orientation towards the future, towards social progress. After 70 years, one or another form of senile dementia, dementia is rarely found among outstanding figures of science and art, creative activity acts as a factor in psychological and biological longevity. Self-organization of vital activity is of paramount importance in the period of late ontogenesis as one of the most important conditions for longevity. Active longevity of an elderly person is thus promoted by his development as a socially active person and as a subject of creative activity.

§ 15.7. AGE DEVELOPMENT POTENTIALS

Successful formation of a comprehensively and harmoniously developed personality is possible only if the laws of its development are taken into account.

The inclusion of a person in different systems: biological, ecological, social - determines the extreme complexity and heterogeneity of the determinants and potentials of individual development.

Human development is a single process determined by the historical conditions of social life. The result of the interaction of biological and social in the individual development of a person is the formation of individuality. Its essence is the unity and interconnection of the properties of a person as a personality and a subject of activity, in the structure of which the natural properties of a person as an individual function; the general effect of this fusion, the integration of all the properties of a person as an individual, personality and subject of activity is individuality with its holistic organization of all properties and their self-regulation. The socialization of the individual, accompanied by ever greater individualization, covers the entire life path of a person.

The nature of psychophysiological development is heterogeneous and contradictory throughout ontogeny. General development is the result of mastered activities: labor, knowledge and communication. They significantly influence the formation of the potential properties of a person.

In many works, the facts of a significant change in the indicators of various mental functions as a result of labor activity were revealed. If the first phase of the development of mental functions acts as a consequence of their age-related maturation, then the further progress of functions is primarily due to the formation of operational mechanisms in the process of activity, which can significantly expand the possibilities for developing potentials and contribute to creative longevity.

As the personality develops, the integrity and integrativity of its psychological organization grows, the interconnection of various properties and characteristics increases, new development potentials accumulate. There is an expansion and deepening of the ties of the individual with the outside world, society and other people. A special role is played by those aspects of the psyche that provide the internal activity of the individual, manifested in his interests, emotional, conscious attitude to the environment and to his own activities.

One of the development trends is the generalization of personality relations in the process of its formation: in the course of the ontogeny of integral individuality, there is a gradual elimination of mismatches between the properties of different levels (V. S. Merlin), a person becomes more whole, integrated. Apparently, it can be said that individuality as a product of development, having formed, itself becomes an objective factor in the further course of life and development.

The most important factor in development is general abilities or giftedness. At the same time, the presence of contradictions between the possibilities, potentials of a person and his interests, relationships, directions (that is, between potencies and tendencies) acts as a necessary factor and driving force for the development of individuality. Ways and means of resolving contradictions can be different: the formation of an individual style, a decrease in the level of claims, the emergence of new interests, relationships; development and improvement of the properties of the individual (Ganzen V. A., Golovey L. A.).

A number of studies have established a great similarity in the characteristics of personality development in childhood, adolescence, early, middle and late adulthood, which allows us to speak about the existence of various individual development styles.

Thus, development potentials include individual, subjective and personal characteristics, which, being transformed under the influence of human activities, constitute a kind of combination of individual development potentials.

The age development of a person is considered in different ways, which determines the features of the periodization of age development:

• The order of life events;
• Human biological processes;
• Development in society;
• Ontogeny of psychology.

The age periodization of a person unites the period from conception to physiological death.

To date, there is no single classification of the age periodization of human life, since it has constantly changed depending on time and cultural development.

The distribution of age periods occurs when certain important changes occur in the human body.

Stages of age periodization are periods between the boundaries of a certain age in the system of human development.

Giving a brief definition of age periodization, we can distinguish the following stages:

• The birth of a person;
• Growing up, as well as the formation of certain physical and social functions;
• Development of these functions;
• Old age and inhibition of the functioning of the body;
• Physical death.

Each person after birth goes through all stages of life sequentially. They make up the life cycle.

It should be noted that there is not always a coincidence of the "passport" age with the social, biological and psychological.

What is age periodization?

Consider the main periods of a healthy person's life, which are distinguished by age periodization in psychology. The characteristic of age periods is based on psychological ontogenesis.

Periodization age from a psychological point of view

1. Prenatal segment, in which 3 stages are distinguished:

• Pre-embryonic. The duration is determined by two weeks, when fertilization occurs in the egg;
• Embryonic. The duration of the period is until the beginning of the third month of pregnancy. The period is characterized by the active development of internal organs.
• Fetal stage. It lasts from three months of pregnancy until the birth of a child. All vital organs are formed, which must function clearly and allow the fetus to survive after childbirth.

2. Childhood.

• From zero months to a year;
• Early childhood, which lasts from one year to three years. It is characterized by the manifestation of autonomy and independence; intensive development of speech skills.
• Preschool is from three to six years.

During this period, the intensive development of the child takes place, the stage of social manifestations begins;

• School age of the younger group. From six to eleven years old, the baby is actively involved in social life; intensive intellectual development.

3. Adolescence.

• Teenage years.

Time of intense puberty, which lasts up to fifteen years. There are significant changes in the functioning of body systems. Under their influence, the view of one's own "I" and ideas about the surrounding reality change.

• Youth time.

The duration of the period is from sixteen to twenty-three years. From the point of view of biology, the organism has become an adult. However, based on social development, this cannot be said. There is a desire to become self-reliant and independent in the absence of social responsibility.

All important decisions related to later life are made at this time: the choice of a life path, profession, self-determination, the formation of self-awareness and attitudes towards self-development.

The transition from one age period to another provides for the emergence of crises, those moments that are considered to be turning points. They occur due to changes in the physiology and psychology of a growing person. Crises are the most difficult stages of the life path, which cause certain difficulties for the growing person himself, as well as for the people who surround him. There are two types of tipping points: small and large.

Small crises (1 and 7 years old, youthful crisis) appear with the emergence and development of skills that did not exist before, the increasing role of independence.

Major crises (birth, three years, adolescence) are characterized by a complete restructuring of social and psychological relationships. This is a time of great change, which is accompanied by emotional outbursts, aggression, disobedience.

4. Maturity.

• Youth. Lasts up to 33 years. The period of active personal relationships associated with building a family and having children. Development of professional activity. Time to assert yourself in all areas of life: sex, love, career.
• Crisis of thirty. By this time, many achieve what they so aspired to. There comes a turning point in life when a person begins to search for the meaning of life. Often disappointed in what he has. Seeks to change jobs, education, circle of acquaintances and friends. According to statistics, most divorces occur during this period.
• period of stabilization. From 35 to 45 years old, as a rule, people are satisfied with what they have achieved. They no longer want change, they want stability. Self-confidence comes, they are satisfied with success in their careers. Most often, the state of health is consistently good. Family relations are stabilizing.
• Decade of crisis (45-55 years).

The first signs of approaching old age begin to appear: the former beauty is leaving, well-being and health in general are deteriorating.

There is coldness in the family. Children, having become adults, lead an independent life, alienation occurs in relations with them. Fatigue and depressive moods are frequent companions of this age. Some try to find salvation in dreams of a new bright love (or make a dream come true). Others "burn" at work, providing a dizzying rise in their careers.

• period of equilibrium. The age from 55 to 65 years is characterized by a gradual withdrawal from social life and work. This is a period of relative calm in all spheres of life.

5. Old age.

There is a rethinking of all life, reflection on spirituality and a reassessment of actions. An overview of the past years from the point of view of philosophy: was life wasted in vain or was it rich and unique.

At this time, crisis periods appear associated with a rethinking of the life lived.

• Personal assessment that does not affect the professional sphere;
• Attitude towards aging and the appearance of signs of a clear deterioration in health and appearance;
• Understanding and accepting death.

1) Thinking about its inevitability, a person first feels the horror of helplessness, since he cannot prevent this event.

2) Anger that is poured out on all the young and healthy who are nearby. It comes with the realization that human life is coming to an end and nothing can be done about it.

3) An attempt to make a deal: with doctors or through repentance. A person "begs" for years of life, following all the doctor's orders, self-medicating or actively attending church.

4) Depression. Awareness of imminent death does not leave a person. He withdraws into himself, often cries, thinking about the relatives and friends he will have to leave. There is a complete lack of social contacts.

5) Acceptance of death. Humble expectation of the inevitable end. The state when a person is already psychologically dead.

6) The onset of clinical death is characterized by complete cardiac arrest and cessation of breathing. Within 15-20 minutes, a person can still be brought back to life.

7) Physiological death is associated with the cessation of all body functions.

The definition of this age periodization is associated with the physiological characteristics of the body, the level of development of the psyche, as well as the main behavioral characteristics of a person.

Philosophical concept of age periodization

Since ancient times, in different countries, scientists had their own idea of ​​the concept of age characteristics. Modern age periodization successfully uses the proposed models.

For example, in China, it was believed that human life is divided into 7 periods, and the age from 60 to 70 years was considered the best. This time was called the spiritual flowering of man and the manifestation of his highest wisdom.

Hippocrates divided human life into 10 stages, each of which lasted 7 years. Timekeeping began at birth.

The division of the stages of the life path according to Pythagoras is very interesting. He believed that age periodization is a similarity of the seasons.

• Spring.

Beginning of life. The period of formation and development of personality. Passes from birth to 20 years.

• Summer. Young years from 20 to 40 years.

• Autumn. The best years of a person, the flowering of creativity. Lasts from 40 to 60 years.
• Winter is old age, which comes from the age of 60.

Pythagoras believed that everything in human life is characterized by numbers that have magical properties.

The scientist assumed that the age periodization of development is the changing "seasons" of life, and a person is a part of natural life.

At the heart of his age periodization and characterization of periods is the idea of ​​eternal life through reincarnation and change.

Does age really matter?

Each of us is free to determine by what criteria to determine the age period in which he lives. After all, the concept of "age" is very relative.

Someone considers himself young as long as external attractiveness and good health remain. Often people try by all available means to prolong this outward manifestation of youth. And someone and 80 leads an active lifestyle, attracting others with their optimism. As a rule, such people get sick very little, keeping active until old age.

Remember that age is determined by the state of mind, not by the numbers in the passport.

Coursework in Developmental Psychology

on the topic of:

PERIODS OF HUMAN LIFE

Introduction

1. Childhood period

2. Period of maturity

3. Old age

Conclusion

List of used literature

The concept of "age" covers the period from birth to the calculated moment, however, it is advisable to take into account the period preceding the birth of a person, i.e. embryonic development, since it is at this time that all the distinctive features of a particular person are laid down. The embryonic period (embryogenesis, or germinal period) begins from the moment of fertilization of the egg and ends with the exit of the young individual from the mother's body - the birth of a new creature. The entire period after birth is called postembryonic. In addition, embryogenesis is divided into two periods. In medical practice, two concepts are usually used: during the first 8 weeks, the developing organism is called the embryo; starting from the 9th week (i.e. from the moment the organ rudiments are formed) - by the fetus.

Genetic studies have shown that the development of traits characteristic of a given organism occurs under the control of the genetic apparatus, i.e. At different stages of growth and development of an organism, different genes are sequentially turned on.

The study of the genetic program of the embryonic period of development of the organism is important in order to identify in the unborn child a predisposition to various diseases of the nervous system, metabolic diseases and others that can be determined precisely during the period of embryogenesis. Knowledge of the causes and nature of the course of such diseases, revealed in the process of medical genetic counseling, makes it possible for specialists to calculate and “predict” the degree of risk of transmission of genetic disorders to offspring.

The whole life of a person after his birth is divided into certain age periods.

Medical practice and life make their own adjustments to the classification of a person's age periods. In particular, the entire time span of human life began to be divided into two groups of age periods. The first of them covers the period of the most dynamic and intensive growth and development of the body (age periods in children with the allocation of the period of intrauterine development). The second group (age periods of an adult) covers a segment of a person’s life, whose body, after a relatively long stabilization of the development of functions and structure, begins to experience changes associated with subsequent aging and the inevitable result - the death of the individual. Each age crisis requires the most attentive attitude: someone needs to consult a therapist, neurologist or sexologist, someone should turn to doctors of a different specialty. But in all cases, an attentive, benevolent and tactful attitude on the part of relatives, friends and just surrounding people is required.

In this course work, a study of the periods of human life is carried out.

1. Childhood period

The entire period of childhood is characterized by constant development and growth. A variety of internal (endogenous) and external (exogenous) factors influence the course of a child's development. Endogenous factors are understood as the characteristics of the organism and its functional systems, formed in the ancestors under the influence of the environment and inherited by the child, as well as formed in the child himself under the influence of exogenous factors. Residual changes after infectious diseases, injuries of the nervous system, and similar consequences, being of exogenous origin, become endogenous factors after their formation. The environment in which the child grows up becomes dominant. Nutrition plays a huge role. Proper organization of regimen and care, disease prevention - all this can prevent developmental disorders in children at all ages.

Neonatal period characterized by incomplete development of all organs of the baby, which is poorly adapted to the factors of its environment. The duration of this period is determined by the time of adaptation of the body of the newborn to new conditions of existence and is approximately 10 days.

infancy period determined by the period of breastfeeding. Conventionally, its duration is considered equal to 1 year (1st year of life). The child during this period, as in the previous one, is extremely helpless, it requires constant and careful care. Insufficient development of the digestive apparatus with a relatively high need for food due to intensive growth requires proper nutrition. Errors in determining the quality and quantity of food can contribute to the rapid development of digestive disorders.

In children of the first 2-3 months. life, the system of thermoregulation is poorly developed. Thin and vulnerable skin, the weakness of most of the barrier functions make children in the first months of life more susceptible to various infections. There is a lack of immunity. At the age of 5-10 months. the child is most vulnerable to infections. This circumstance is associated with a decrease in passive immunity (due to a weakening of the action of maternal antibodies entering the child's body through the placenta or with mother's milk) and insufficiency of its own active immunity due to the imperfect development of the immune system of the child's body in the first year of life.

Especially dangerous is the manifestation of the weakness of the immune system for children living in large cities with developed industry, as well as in large industrial centers, where in recent years there have been massive cases of children with various kinds of allergic diseases. This problem has received great social significance and requires solutions from government agencies. The disastrous state of the environment in many areas threatens the health of the population, especially children, both those already born and those still in the womb.

preschool age represents a fairly long period of human life. It is usually divided into two age groups: toddlers (1-3 years old) and actually preschool age, or kindergarten age (3-6 years old).

Such a division is quite artificial and is mainly due to social reasons. A child who has gone through a nursery and a kindergarten is more sociable, easily fits into a new team, which is very important when starting school, acquires immunity to certain infections that are most common in children's groups, etc. At the same time, life has shown that a baby brought up to 3-4 years at home has a higher level of mental and physical development, perceives the school curriculum better, is more educated. This, of course, is noted in cases where the child is given enough time and attention at home. The period of preschool age is also called the “period of milk teeth”. This name emphasizes the biological feature of the age period. Indeed, it is in this age interval of a child's life that the so-called milk teeth appear and grow, which is accompanied by the development and improvement of the digestive system. The child gradually acquires the ability to consume and assimilate almost any food, which makes it possible to increase growth and body weight, improve motor skills, etc.

Preschool age is characterized by great mobility of the child, increased curiosity and activity, the desire for initiative and action. To prevent the development of egoism and egocentrism caused by the described qualities, the child should be taught the rules of collective interaction. However, such work should in no case kill the spirit of independence and initiative in him, should not turn him into a "cog" of a complex community in which he has to exist. The main thing is to instill in a future member of society respect for their own kind, to teach him to live in society, but not to suppress his personality. This is a difficult, difficult, but noble task. We can easily find examples and “anti-examples” in our society, where for decades there has been a purposeful destruction or “re-education” of all those who in the slightest degree stood out among their compatriots. The result of such “work” with the younger generation was an abundance of ordinary gray personalities, incapable of any independent, let alone creative activity.

It should be borne in mind that in preschool children there is a gap between the desire for active expression of their inherent mobility and the real capabilities of the body. The high mobility and curiosity of the child at the same time are accompanied by rapid fatigue, since the adaptive capabilities of the respiratory and cardiovascular systems are much lower than in adults. Games at this age should be considered as a workload.

Overfatigue, overload lead to the development of neurotic reactions, changes in the behavior and character of the child. This must be remembered when organizing the education of a school-age child.

School age conditionally divided into junior, middle and senior. A common feature of primary school age is the intensive course of the processes of growth and development of the organism. Annual increases in length range from 2.5 to 7 cm, and in body weight - from 1 to 4-5 kg. It should be noted that in this age group, boys develop much faster than girls. The ossification and growth of the skeleton continues, but since the ossification of the spine is not completed, it remains flexible and pliable. With prolonged incorrect position of the body, the development of curvature of the spine is possible. There is an increase in muscle tissue, the formation of the nervous apparatus of the muscles ends, their strength increases. The lung tissue grows, the vital capacity of the lungs and their minute volume increase. There is an increased excitability of the respiratory center, in connection with which even a slight physical load causes an increase in breathing. At the age of 7-8 years there is an intensive functional development of the brain with a relatively small increase in its mass.