10. Psychophysiological functions and their development in ontogenesis.

Basics of psychophysiological development and lifestyle of a child at different ages
The body of the child is continuously growing and developing. At various periods of his life, significant anatomical and functional changes occur in various body systems.
The main stages of development are prenatal and postnatal, starting from the moment of birth. During the prenatal period, tissues and organs are laid down, their differentiation occurs. The postnatal stage covers all childhood and is characterized by continued maturation of organs and systems, changes in physical development, and significant qualitative changes in the functioning of the body.
The development of individual organs and systems does not occur in isolation, but in the mutual influence provided by the coordinating role of the child's motor activity.
Each age period is characterized by its specific features. The transition from one age period to the next is designated as a crucial stage of individual development, or a critical period. In the postnatal development of a person before the onset of adulthood, there are three critical periods:
1. Age from 2 to 3.5 years, when the child begins to actively move, the formation of speech, consciousness, improvement and continuation of the formation of conditioned-reflex activity, orientation and research activities. The nervous system is especially vulnerable, its overstrain leads to the disruption of mental development and the appearance of mental diseases. During this period of ontogenesis for parents and caregivers, it is important to take all possible measures to prevent child injuries;
2. Age 6 - 8 years (the beginning of schooling), when the lifestyle changes, adaptation to the school regime is underway, new responsibilities appear, physical activity drops;
3. At 11–15 years, hormonal balance changes occur due to the maturation and restructuring of the endocrine glands. During this period there is a risk of many disorders in the adolescent's state of health.
Newborn (up to 10 days). An essential feature of this period is the adaptation of the organism to new conditions of existence. A child is born with vital unconditional reflexes. Body temperature is unstable. A baby develops better if it is brought to the mother’s breast for the first feeding 15 to 20 minutes after birth, since the colostrum contains many biologically active substances that stimulate its immunity. In addition, in this case, milk appears faster in the mother’s breasts, and early contact of the child with the mother through the mechanism of imprinting forms a trace in the brain that is favorable for adaptation processes in the outside world. From the very moment of birth, restrictions on the movements of the child should be minimal, since physical activity has a positive effect on all physiological systems.
The breast period (up to 1 year) is extremely important in the effectiveness of the full-scale deployment of the human genetic program. In this regard, a properly organized lifestyle of infants is of particular importance, including:
1. Breastfeeding with mother's milk. The value of such milk for a child is determined not only by its plastic and energy value, but above all by the fact that it is in genetic terms fully consistent with the characteristics of the body of the child. In addition, it contains biologically active substances that stimulate the immune system and the vital activity of the child. It is indicative, therefore, that by six months the infant doubles the body weight that was at birth, although calculations show that the substances it consumes in the mother's milk are only enough to increase the weight by 50 - 60%. Therefore, a healthy lifestyle for a nursing mother is especially important, allowing the child to get good nutrition. In turn, the latter provides the body of the child not only with a full-fledged energetic material, but also with substances necessary for actively developing organs and tissues.
2. Infant motor activity is important in many ways. First of all, it provides thermal stability and the timely formation of motor functions. The main condition for the organization of the motor activity of an infant is freedom of movement, that is, the opportunity for the child at any given moment to perform the movements for which he is now ready.
3. Mental comfort involves a number of conditions, including:
- unity of requirements for the child by the parents;
- sufficient information support, including voice communication, motor activity, etc .;
- positively tinged emotional environment;
- maintaining the child’s desire for independence.
Early childhood (1 - 3 years). Intensively developing body systems. Finally, the ratio of the nucleus tone of the sympathetic and parasympathetic autonomic nervous systems is formed. In the second year of life, the child grows by 10 - 12 cm, and in the third - by about 7 cm. Spinal curvatures are formed. The mechanisms of speech are rapidly developing, which are associated with the complex development of the cortical zones of speech. In the lifestyle of a child's early childhood age, it is important to ensure all its components. At the same time, full-fledged physical activity plays a special role, through which the child largely learns the world. Play, hardening, gymnastics, massage, walks provide the child with normal physical development. It is unacceptable to overfeed the child, and the best way to regulate his nutrition is to follow the recommendations of B. Spock: “Do not overfeed the child - he will eat as much as he needs!” It is only important to provide the child with a diet that includes a maximum of natural nutrients, and do not abuse sweets, salt and baking.
Two things are important in ensuring mental health. First, to support in the child his desire for independence and initiative. Secondly, based on the didactic principle of consciousness and activity, one should explain to the child (at the level of concepts available to him) his actions and demands and not dismiss his questions.
First childhood (4 - 7 years). There is a slowdown in growth rates up to 4 - 6 cm per year, the structural formation of the brain ends. Increased coordination of movements. The spine is flexible and pliable to the formation of posture, therefore, violation of hygienic requirements can lead to irreversible deformation. Muscles have low stamina and are not capable of power stresses.
For physical development of children, improving their respiratory and cardiovascular systems, hardening the body, the formation of correct posture and the correction of its disorders are useful swimming lessons.
The second childhood (8–11 girls, 8–12 boys) is associated with a period of schooling, which requires a certain level of physiological and mental development, ensuring the child’s painless adaptation to the school regime and the possibility of learning the programs. Under these conditions, the decisive indicator that determines the possibility of learning is not the passport age, but the degree of functional readiness of the child to the requirements of the school.
Ossification of the skeleton continues, intensive development of the muscles of the hands. The skeleton is elastic and flexible with weakness of the deep muscles of the back, which can lead to a violation of posture. Therefore, the movement must be diverse, without significant static loads. Thanks to the strengthening of the processes of internal inhibition and the concentration of cortical processes, children become more focused, attentive and disciplined. However, emotional, mental and physical overloads lead to a decrease in the reliability of the body, the development of neuroses and other health disorders.