Stages of the formation of higher nervous activity in a child. Dominant principle. Features of the higher nervous activity of children

28.04.2019

Stages of the formation of the highest
nervous activity in
child. Dominant principle
Gavrilova Yu.A.
Doctor of the highest category
Candidate of Medical Sciences

Ontogenesis is divided into two periods: prenatal
(intrauterine) and postnatal (after birth).
prenatal - from the moment of conception and formation of the zygote to
birth;
postnatal - from the moment of birth to death.
The prenatal period, in turn, is divided into three
period: initial, embryonic and fetal.
The initial (pre-implantation) period in humans
covers the first week of development (from the moment
fertilization before implantation in the uterine lining).
The embryonic (pre-fetal, embryonic) period - from
the beginning of the second week until the end of the eighth week (from the moment
implantation before the completion of the organ laying).
The fetal (fetal) period begins from the ninth week and
lasts until birth. At this time, increased growth occurs.
organism.

The postnatal period of ontogenesis is subdivided into
eleven periods:
1st - 10th day - newborns;
10th day - 1 year - infancy;
1-3 years - early childhood;
4-7 years old - first childhood;
8-12 years old - second childhood;
13-16 years old - adolescence;
17-21 years old - adolescence;
22-35 years - the first mature age;
36-60 years - the second mature age;
61-74 years old;
from 75 years old - old age,
after 90 years - long-livers.

HISTOGENESIS OF THE NERVOUS SYSTEM

During embryogenesis, nerve tissue
develops from a dorsal thickening of the ectoderm
- the neural plate, which, bending forms
the neural groove, and then the neural tube. Part
cells located above the neural tube
form a ganglion plate and a nervous
crest.
From neural tube neurocytes are formed and
neuroglia of the brain and spinal cord.
From the ganglionic plate - neurons and neuroglia
ganglia.
Stage three, stage five brain bladders: 1st -
cerebral hemispheres, 2nd - intermediate
brain, 3rd - midbrain, 4th - hindbrain, 5th -
medulla

Neurulation (scheme).
A - the stage of the neural plate;
B - the stage of the neural groove;
B - stage of the neural tube.
1 - nerve groove;
2 - nerve roller;
3 - cutaneous ectoderm;
4 - chord;
5 - somite mesoderm;
6 - neural crest
(ganglion plate);
7 - neural tube;
8 - mesenchyme;
9 - endoderm.
The cells of the neural crest migrate and produce elements of the spinal,
cranial, autonomic ganglia, arachnoid and soft cerebral
membranes, pigment cells (melanocytes), cells of the medulla
adrenal glands.

Antenatal period

In the antenatal period, the opportunity
the development of conditioned reflexes has not been proven.
Even at premature babies conditional
reflexes are not developed during
(approximately) the term of prematurity. but
the structure of the cerebral cortex reaches
high differentiation by the end
antenatal period of development, which is associated with
its intensive functioning.
A.

For 2-3 months. before birth, the fetus, responding with distinct movements to a sudden sound stimulus, with the repetition of the sound, gradually reduces the

For 2-3 months. before birth, the fetus, reacting
distinct movements to a sudden sound
irritation, when the sound is repeated gradually
reduces motor reaction and then
completely stops movement. If after
to give other irritants, including
other sounds, you can again observe the motor reaction of the fetus. Thus, in
second
half
antenatal
period
functions
bark
should
to define
how
indicative research

Neonatal period

Neonatal period (from birth to 1 month). TO
at the end of the first week of life, the child develops
conditioned reflex at the time of feeding. So, for
strict regimen 30 minutes before feeding
leukocytosis and increased gas exchange are detected,
and then the child wakes up. Nictitating
conditioned reflex (conditioned stimulus - bright
light, unconditioned - vibration), motor defensive to sound (unconditioned stimulus, electrocutaneous irritation) are also formed in
the end of the first - the beginning of the second week of the child's life.

Neonatal period

By the end of the second week of life appears
conditioned sucking reflex to "position
feeding "(Bekhterev - Shelovanov reflex).
Conditioned stimuli are the position
the baby's body, typical for feeding, and
tactile, proprioceptive and vestibular
irritation that occurs when
swaddling before feeding;
the reinforcement is feeding.

Breast age

Breast age (from 1 to 12 months), in a child on the 2nd
month of life there is a specific
human, social in nature
the need for communication with an adult. In that
period due to the maturation of the central nervous system and analyzers, and
also by the influence of the external environment and others
child of persons, GNI is rapidly developing: rapidly
are developed and become more durable
conditioned reflexes, they are developed
internal inhibition, emotions appear on
the environment and people around you,
after 6 months speech begins to develop.

12 months

By the end of the 1st year or a little later, when the child does
the first steps, a very important stage of knowledge begins
environment. Moving on your own, bumping
on objects, feeling them and even tasting them, a child
takes over
feeling
three-dimensionality
space,
significantly complementing your visual and auditory
perception, develops important skills of active
knowledge of the world. At this stage, motor development is often
associated with speech: the more confidently the child moves, the
better he masters speech, although deviations in
the form of dissociation of these functions.

Cognition

Cognitive
activity
v
aged 1-3 years. At the 2nd year of life, she
inextricably linked to muscle
sensations resulting from
manipulating the object. Thinking
the child in the early stages is formed as
Thinking in action.

2nd year

In the 2nd year of life, the foundations are laid
mental activity, preparation for
independent
walking,
To
speech
activities.
Perception
various
irritants, contact with the outside world
are of great importance to them during this period.
Deficiency of irritations, their monotony is noticeable
affect the further mental
development.

2nd year

Under the age of 2-2.5 years, a child
how
usually
sociable,
friendly, easy to enter into
contact with strangers, rarely experiences a feeling of fear.

2-3 years

2nd and 3rd year child behavior
life strikes stormy and persistent
research
activities.
The child reaches out for every object,
touches him, feels, pushes, tastes
raise. The leading role belongs to the hand,
therefore it is necessary to learn how to play
skills (cubes, drawing), household
skills
(independent
dressing,
fastening buttons, lacing shoes and

3rd year

Gradually, the child develops
system
adequate
action
with
various objects: on the chair he
sits down, eats with a spoon, drinks from a cup. If
actions
baby
with
subject
limit,
his
cognitive
activity turns out to be impoverished,
at the same time it lingers in its
development and thinking.

3rd year

In the 3rd year of a child who has already mastered phrasal speech
and having, although small, but its own
life experience, there is a very strong craving for
independence. One of the consequences of this
aspiration is stubbornness, not always understandable
parents. This stubbornness and self-will is significant
increase if parents try to limit
independence of the child. In this age period
various neurotic reactions can be observed
psychogenic and somatogenic nature.

3-5 years

V
age
3-5
years
is improving
conditioned reflex activity, increases
the number of dynamic stereotypes, pronounced
play activities that contribute to the development
intelligence. For this age, stormy
manifestations of emotion, which, however, have an unstable
character, therefore this period is called age
affectivity. Children try to assert themselves
highlight among other children, attract attention.
At this age, the character changes significantly
orienting reactions: they used to strive all
touch, now they ask the questions: "What is this?",
"The name of?" etc. The child determines the shape of the object
already "by eye".

5-7 years

The period from 5 to 7 years is characterized by the fact that
strength, mobility and
balance of nervous processes. it
expressed in increased efficiency
cerebral cortex, more stability
of all kinds internal braking decreasing
generation of excitation. This is why children
are now able to focus on
for 15-20 minutes or more. Developed
conditioned reflex reactions are less amenable
external braking.

5-7 years

Children begin to read, write, paint,
are very active in learning about the outside world,
surrounding objects - everything strives
disassemble, unscrew, break, peep
"Inward" is still asked a lot
questions.
Children
already
v
condition
manage your behavior based on
preliminary verbal instructions.

5-7 years

They
may
hold
program
actions,
consisting of
from
a number of
motor operations. As is known,
anticipatory reactions
actions are formed with the participation
frontal cortex. Precisely to the 7-year-old
age, morphological
maturation
frontal
department
bark
cerebral hemispheres.

5-7 years

Between the ages of 5 and 7, it increases
the role of abstract thinking. If before
until now the main thing was thinking in
action,
then
now
starts
dominate verbal thinking with
inner speech. The baby starts
use concepts that are already
abstracted
from
action.
A seven-year-old assesses himself as
important
personality,
a
own
activity
how
publicly
significant.

Junior school age

Junior school period (girls from
7 to 11 years old, boys from 7 to 13 years old). Have
child 7-8 years old motor skills are already well developed
and
speech,
he
knows how
thin
analyze the situation, he has developed
feeling of "psychological distance" in
relationships with adults. In the same time
he does not yet have sufficient self-criticism
and
self-control,
not
worked out
ability
To
long
concentration;
v
activities
game elements prevail.

Junior school age

It should be noted that starting from the 7-year-old
age boys in maturing systems
organism and development
GNI lag behind
girls for about 2 years. In that
aged basic nervous processes
(agitation and inhibition) have
significant
by force,
mobility,
poise and approaching
that of an adult. All kinds
internal
braking
developed
good enough.

Adolescence

Adolescence (boys from
13 to 17 years old, girls from 11 to 15 years old).
During this critical period, which also
called transitional (pubertal),
changes significantly
conditioned reflex activity
adolescents, and their behavior is characterized by
a clear predominance of excitement.

Adolescence

Reactions in strength and character are often
inadequate to the stimuli that caused them
and
accompanied by
redundant
additional
accompanying
movements of the arms, legs and trunk (especially in
boys), just as it was in
early age. Conditional inhibition,
especially
differentiating,
weakens. This is due to the increased
excitability of the central nervous system, weakening of the process
braking and, as a result, irradiation
excitement.

Adolescence

The rate of formation of conditioned reflexes
on
immediate
(visual,
sound, tactile) stimuli now
increases while the process
education
conditional
reflexes
on
verbal signals are difficult, i.e.
there is a weakening of the value of the second
signaling system. Speech in adolescence
age clearly slows down, responses to
questions tend to become very
concise and stereotyped, a vocabulary like
would be impoverished.

Adolescence

In order to get an exhaustive
an answer for some reason, it is necessary
ask a number of additional questions.
Pursuit
to be
adults
maybe
manifest in imitation of habits
adults,
v
overthrow
of all
authorities,
active
resistance
any coercive measures. In adolescents
there is interest in such problems as
meaning of life, love, happiness.

Adolescence

V
this
period
vegetative
regulation
imperfect: excessive sweating is noted,
instability blood pressure, dermatrophic disorders, lability of vascular
reactions.
Acceleration phenomena observed in recent
decades are likely to have an impact on
shaping
neuropsychic
functions.
However, somatic development in puberty
period is somewhat ahead of the neuropsychic,
what
maybe
drive
To
functional
disorders of the nervous system.

Adolescence

The listed changes are explained
hormonal
restructuring
organism
(puberty), worsening
nutrition and supply of the brain
oxygen. This is due to
the fact that the development of cardiovascular
the system lags behind the growth of the body; Besides,
increasing the functions of the adrenal glands and other
glands internal secretion leads to
increased adrenaline in
blood and, naturally, to vasoconstriction.

Adolescence

Therefore, in adolescents in transition
rapid fatigability is noted
mental and physical
(dizziness, sometimes shortness of breath, often
pain, increased heart rate).
period
as with
loads
head
For girls, this period is more difficult than
at
boys,
at
which
functional
disorders are less pronounced. Apparently, these
the differences are explained by the greater motor
the activity of boys, training of the cardiovascular system and the central nervous system, which is partially
smoothes the indicated functional disorders.

Adolescence

Around the middle of the transition period
adolescents have mental
imbalance with abrupt transitions
from one state to another - from euphoria to
depression and vice versa, a sharp critical
attitude
To
adults,
negativism,
affective states, extreme
resentment; girls have a tendency to
tears.

Adolescence

Period
hormonal
restructuring
the body requires a reasonable attitude
adults to teenagers. Conflicts between
adolescents and their parents often
arise due to underestimation of the features
GNI during puberty.
Correct, healthy rhythm, calm
situation,
benevolence,
interesting activities for teenagers, including
including physical education, are
good prevention of functional
disorders.

Adolescence

Gradually
starts
level off
hormone
imbalance, the lag in the development of the cardiovascular system is eliminated, the conditions for the activity of the central nervous system are improved.
Neurons become more mature, synthesis increases
nucleic acid metabolism nerve cells, increases
the role of the frontal areas of the cortex, the specialization ends
various parts of the cerebral cortex in perception and
assessment of information, interhemispheric integration, and how
as a result, the IRR is optimized. Latent
periods of reactions to verbal stimuli, increases
internal inhibition. Better at the age of 17-18
memory, GNI reaches its perfection, the body
considered ripe.

Dominant

L.S. Vygotsky identified several interest groups
("dominant") of a teenager:
- "egocentric dominant" (interest in one's own
personality);
- "the dominant was given"
distant events);
(subjective
significance
- "dominant effort" (craving for resistance, to
overcoming, to a volitional effort that can
manifest in negative forms - in stubbornness,
hooliganism, etc.);
"dominant
romance "
unknown, risky, to
heroism).
(pursuit
adventures,

Features of the development of GNI in children.

The formation of GNI in children is closely related to the maturation of the cerebral cortex. It is known that the structural basis of complex mental forms of behavior is the associative zones of the cortex, especially those located in the frontal and inferior parietal regions. The area of the associative cortex after birth increases 9 times and in adults it occupies 2/3 of the entire surface of the cortex.

VNI in children of the first year of life. In fetuses, conditioned reflex activity has not been proven. How early conditioned reflexes are formed in the human infant has been investigated by Lipsitt and Keys. In 1946, they conducted a study on the development of a conditioned reflex in three-day-old infants. Ten experimental infants were combined 20 times with a pure sound tone (conditioned signal) followed by nipple feeding (unconditioned stimulus). Ultimately, the babies in this group sucked only in response to sound. Children from control group no sucking movements were performed, since the sound tone was not reinforced by the nipple. Thus, the teaching of an infant is possible from the first days of his extrauterine life. The very first natural conditioned reflexes appear in the second week after birth for a while, if the feeding regime is strictly observed. Already 30 minutes before the next feeding, the number of leukocytes in the child's blood rises, gas exchange increases and the child wakes up. This reaction is called a natural conditioned reflex.

At the same time, the child develops conditioned reflexes in the form of sucking movements to the position of the body for feeding.

By the end of the second week after birth, the child has stable conditioned reflexes from the vestibular and hearing aids. The child falls asleep faster on motion sickness and lulling.

2 months after birth, conditioned reflexes can be developed in infants to stimulate all types of receptors. By this time, children develop visual and auditory memory. At the age of 3 to 6 months, the relationship between the skin-tactile, motor and visual analyzers is established, on the basis of which purposeful hand movements are formed.

At the age of 5 to 8 months, the child studies the subject visually, with the help of hands and mouth. The child can shift things from hand to hand, grab objects with two fingers, can clap and hit with toys - these actions are associated with the formation of fine motor skills.

Gross motor skills are developed by the inclusion of large muscles, which allows children to sit up, stand with support, crawl and walk with support. Children exhibit exploratory behavior.

Games at 6-7 months lay the foundation for the subsequent development of thinking and speech.

At 7-8 months, the child is able to distinguish between mechanical toys and living objects.

Conditioned reflexes to a word appear from 7 months of age - these are the first manifestations sensory speech. Correct reaction in words it is manifested only in a familiar environment.

At 11-12 months, the child walks independently. During this period, he actively explores the world: he examines the contents of the boxes, turns on the appliances, climbs into the cabinets, on the windowsill. He independently masters the methods of eating and drinking.

The specialization of conditioned reflexes is inextricably linked with the development of cortical inhibition.

Unconditioned external inhibition manifests itself in a child from the very beginning of conditioned reflex activity. Any extraneous stimuli inhibit conditioned reflexes in the child. This is one of the reasons for the inconsistency of conditioned reflexes in small children.

Conditional (internal inhibition) does not appear immediately after the birth of the child. The extinguishing and differentiating inhibition of conditioned reflexes can be developed in children older than 2.5-3 months. But differentiation is developed only for strongly distinguishable stimuli. For example: the beep sound is a conditional reinforced signal, and the ring sound is an unreinforced signal. In the process of prolonged development of differential inhibition, the child will begin to distinguish between these signals. Only by the age of 6 months does the child acquire a more subtle differentiation.

Braking type conditional brake arises later. From 5 months, the child shows signs of delayed inhibition.

From the very first minutes after birth, a child has negative emotions associated with the need to meet the needs for food, warmth, and comfort. Meeting the needs of a newborn removes negative emotions, but does not cause positive ones. And only at the beginning of the second month of a child's life appear positive emotions in response, not an affection, a smile of an adult. From this time on, the child has a need emotional communication. Emotional deprivation even in a healthy child, it leads to developmental delay.

Newborns sleep 20-21 hours a day, at the age of 1 year - about 14 hours. Newborns are characterized by repeated (6-7 times a day) change of sleep and wakefulness (polycyclic sleep). The number of cycles decreases with age. The child sleeps 3 times a day a year. In newborns, REM sleep has a long duration and takes about half of the total sleep time, i.e. about 10 hours.

During the first year of life, the brain grows 2-2.5 times.

The development of GNI during early childhood (1-3 years). Further development of the brain is in progress. Adequate actions with objects are gradually formed. The child understands their purpose. The child develops a dynamic stereotype. But the mobility of the nervous processes providing switching from one type of activity to others is insufficient. Changes in the order of signals in the developed stereotype causes the child to find it difficult to form a response. Therefore, children under 3 years old require a careful attitude towards the developed positive habits.

At 2 years old, the child is active, masters complex forms activities (cycling, climbing stairs). The child dresses, undresses, draws on his own; improves speech. Active recognition of objects, operating with them in 2-3 years is closely related to thinking in action. Visual activity is the most important indicator of a child's development. Obstacle to the goal creates anger. The first outbursts of rage are noted in children aged 1 to 2 years, they are fast-passing and are mainly aimed at objects.

From 2 years of age, aggression manifests itself in refusal or prohibition. This is a struggle for power over adults. At 3 years old, a child requires independence - an age crisis. Children start to lie early; 70% of children lie, and the smarter the child, the more he lies.

Higher nervous activity during the first childhood (3-7 years). This age is characterized by the further development of all types of conditioned inhibition. Alteration of the stereotype is no longer difficult task... In preschoolers, analytical and synthetic mechanisms are intensively formed, conditioned reflexes to complex stimuli are developed.

For the age of 3-5 years, violent manifestations of emotions are typical, children assert themselves.

Learning to read at 6-7 years of age develops verbal thinking with inner speech. Children at this age are able to control their behavior.

By the age of 7, morphological maturation of the frontal part of the cerebral cortex occurs, which ensures the child's ability to maintain behavior programs. Typological features of GNI in a child aged 6-11 years are not clearly defined, because strength, mobility and balance of nervous processes are not stable. The development of the cerebral cortex is gradually approaching the level of an adult.

GNI during primary school age (7-10 years). Fatigue develops quickly in children. The mechanisms that determine active attention are still underdeveloped. Children take on the role of learner. This is a period of increased stress in the body, hence increased emotionality with a strong need for movement. In the absence of emotional protection, personality deviations easily develop.

GNI in adolescence (from 11 to 15 years old in girls, from 13 to 17 years old in boys). This is the most critical period - since somatic changes in the body are caused by puberty. Dominance of excitatory processes over inhibitory processes is observed. The level of anxiety is high. Differentiation of signals deteriorates, wide irradiation of excitation is manifested. Speech slows down, responses are stereotyped. Conflict is characteristic. A sense of independence develops. A negative consequence of this is a tendency to negative behavior (smoking, alcohol and drug use). V adolescence the structural and functional maturation of the cortex is taking place, its ensemble organization becomes more complicated, the role of the frontal structures of the cortex in the perception of information increases. The specialization of the cortex is coming to an end and the development of GNI is completed.

Children are formed as a result of the morphofunctional maturation of the entire nervous apparatus. The nervous system, and with it the higher nervous activity in children and adolescents, reaches the adult level by about 20 years. The entire complex process of human GNI development is determined both hereditarily and by many other biological and social factors external environment. The latter acquire a leading importance in the postnatal period, therefore, the main responsibility for the development of a person's intellectual capabilities falls on the family and educational institutions.

VNI of a child from birth to 7 years. A child is born with a set of unconditioned, reflex arcs of which begin to form at the 3rd month intrauterine development... Then the first sucking and breathing movements appear in the fetus, and the active movement of the fetus is observed in the 4-5th month. By the time of birth, the child has formed the majority congenital reflexes, which provide him with the normal functioning of the vegetative sphere.

The possibility of simple conditioned food arises already on the 1st-2nd day, and by the end of the first month of development, conditioned reflexes from the vestibular apparatus are formed.
From the 2nd month of life, auditory, visual and tactile reflexes are formed, and by the 5th month of development, the child develops all the main types of conditioned inhibition. Great importance in the improvement of conditioned reflex activity has a child. The earlier training is started, i.e. conditioned reflexes, the faster their subsequent formation proceeds.

By the end of the 1st year of development, the child relatively well distinguishes food, the shape and color of objects, distinguishes voices and faces. The movements are significantly improved, some children begin to walk. The child tries to pronounce single words, and he has conditioned reflexes to verbal ones. Therefore, already at the end of the first year in full swing development is underway the second signaling system and is formed by it cooperative activity from the first.

In the 2nd year of the child's development, all types of conditioned reflex activity are improved, and the formation of the second signal system continues, significantly increases vocabulary; stimuli or their complexes begin to cause verbal reactions. Already in a two-year-old child, words acquire a signaling meaning.

The 2nd and 3rd year of life are distinguished by a lively orientation and research activities... This age of the child is characterized by an "objective" character, that is, the decisive importance of muscle sensations. This feature is largely associated with morphological maturation, since many motor cortical zones and zones of musculocutaneous sensitivity reach a sufficiently high functional usefulness by 1-2 years. The main factors stimulating the maturation of these cortical zones are muscle contractions and high physical activity of the child.

The period up to 3 years is also characterized by the ease of formation of conditioned reflexes to a variety of stimuli. A notable feature of a 2-3-year-old child is the ease of developing dynamic stereotypes - sequential chains of conditioned reflex acts carried out in a strictly defined, time-based order. this is a consequence of a complex systemic reaction of the body to a complex of conditioned stimuli (conditioned for a time - food intake, time, etc.).

The age from 3 to 5 years is characterized by further development of speech and improvement (their strength, mobility and balance increase), the processes of internal inhibition become dominant, but delayed inhibition and conditional brake are developed with difficulty.

By the age of 5-7 years, the role of the signaling system of words increases even more and children begin to speak freely. This is due to the fact that only by the age of seven years of postnatal development does the material substrate of the second signaling system, the cerebral cortex, functionally mature.

GNI of children from 7 to 18 years old. Younger school age (from 7 to 12 years old) is a period of relatively "quiet" development of GNI. The strength of the processes of inhibition and excitation, their mobility, balance and mutual induction, as well as a decrease in the strength of external inhibition, provide opportunities for the child's broad education. But only when learning to write and read does the word become an object of the child's consciousness, increasingly moving away from the images, objects and actions associated with it. A slight deterioration in the processes of GNI is observed only in the 1st grade in connection with the processes of adaptation to school.

Of particular importance for teachers is the adolescent (from 11-12 to 15-17 years old) period. At this time, the balance of nervous processes is disturbed, great strength acquires excitement, the increase in the mobility of nervous processes slows down, the differentiation of conditioned stimuli worsens significantly. The activity of the cortex is weakened, and at the same time the second signaling system. Everything functional changes lead to mental imbalance and conflict in the teenager.

Senior school age (15-18 years) coincides with the final morphological and functional maturation of all body systems. The role of cortical processes in the regulation of mental activity and the functions of the second signaling system increases. All the properties of nervous processes reach the level of an adult, that is, the GNI of older schoolchildren becomes orderly and harmonious. Thus, for the normal development of GNI at each separate stage of ontogenesis, it is necessary to create optimal conditions.

There are still no special receptors, no special locomotor apparatus, or anything similar to the nervous system. An amoeba can perceive irritation with any part of its body and react to it with a kind of movement by the formation of an outgrowth of protoplasm, or pseudopodia. By releasing the pseudopod, the amoeba moves to the stimulus, such as food.

In multicellular organisms, specialization arises in the process of adaptive evolution different parts body. Cells appear, and then organs adapted for the perception of stimuli, for movement and for the function of communication and coordination.

The appearance of nerve cells not only made it possible to transmit signals over a greater distance, but also served as a morphological basis for the rudiments of the coordination of elementary reactions, which leads to the formation of an integral motor act.

In the future, as the animal world evolves, there is a development and improvement of the apparatuses of reception, movement and coordination. A variety of sensory organs appear, adapted for the perception of mechanical, chemical, temperature, light and other stimuli. A complexly arranged motor apparatus appears, adapted, depending on the lifestyle of the animal, to swimming, crawling, walking, jumping, flying, etc. As a result of concentration, or centralization, of scattered nerve cells into compact organs, the central nervous system and peripheral nervous paths. Along one of these paths, nerve impulses are transmitted from receptors to the central nervous system, along others - from centers to effectors.

The human body is a complex system of numerous and closely interconnected elements, united into several structural levels. The concept of the growth and development of an organism is one of the fundamental concepts in biology. The term “growth” is currently understood as an increase in the length, volume and weight of the body of children and adolescents associated with an increase in the number of cells and their number. Development is understood as qualitative changes in the child's body, consisting in the complication of its organization, i.e. in the complication of the structure and function of all tissues and organs, the complication of their relationships and the processes of their regulation.

The growth and development of the child, i.e. quantitative and qualitative changes are closely interrelated with each other. Gradual quantitative and qualitative changes occurring during the growth of the organism lead to the appearance of new qualitative features in the child.

The entire period of development of a living creature, from the moment of fertilization to the natural end individual life, called - ontogenesis (Greek ONTOS - being, and GINESIS - origin). In ontogenesis, two relative stages of development are distinguished:

Prenatal

Postnatal

Prenatal - begins from the moment of conception until the birth of the child.

Postnatal - from the moment of birth to death of a person.

Along with the harmony of development, there are special stages the most abrupt abrupt atomic - physiological transformations.

In postnatal development, there are three such "critical periods" or "age crisis".

An important biological feature in the development of a child is that the formation of their functional systems occurs much earlier than they need.

The principle of the advanced development of organs and functional systems in children and adolescents is a kind of "insurance" that nature gives a person in case of unforeseen circumstances.

Functional system - called a temporary association various bodies child's body aimed at achieving a result useful for the existence of an organism.

The nervous system is the leading physiological system of the body. Without it, it would have been impossible to combine countless cells, tissues, organs into a single hormonal working whole.

The functional nervous system is divided “conditionally” into two types:

Thus, thanks to the activity of the nervous system, we are connected with the surrounding world, are able to admire its perfection, learn the secrets of its material phenomena. Finally, thanks to the activity of the nervous system, a person is able to actively influence the surrounding nature, transform it in the desired direction.

On the highest stage its development, the central implicit system acquires another function: it becomes body mental activity, in which based on physiological processes sensations arise, perceptions and thinking appears. The human brain is an organ that provides the possibility of social life, communication of people with each other, knowledge of the law of nature and society and their and cn use in public practice.

Let's give some idea of conditioned and unconditioned reflexes.

The main form of activity of the nervous system is reflex. All reflexes are usually divided into unconditioned and conditioned.

Unconditioned reflexes are innate, genetically programmed body responses that are common to all animals and humans. Reflex arcs of these reflexes are formed in the process prenatal development, and in some cases - in the process of postnatal development. For example, congenital sexual reflexes are finally formed in humans only by the time of puberty in adolescence. Unconditioned reflexes have conservative, slightly changing reflex arcs, passing mainly through the subcortical parts of the central nervous system. Participation of the cortex in the course of many unconditioned reflexes not necessary.

Conditioned reflexes are individual, acquired reactions of higher animals and humans, developed as a result of learning (experience). Conditioned reflexes are always individually unique. Reflex arcs of conditioned reflexes are formed during postnatal ontogenesis. They are characterized by high mobility, the ability to change under the influence of environmental factors. Reflex arcs of conditioned reflexes pass through the higher part of the brain - KGM.

The question of classifying unconditioned reflexes is still open, although the main types of these reactions are well known. Let us dwell on some especially important unconditioned human reflexes.

1. Food reflexes. For example, salivation when food enters oral cavity or the sucking reflex in a newborn baby.

2. Defensive reflexes. Reflexes that protect the body from various adverse effects, an example of which can be the reflex of withdrawing the hand with painful irritation of the finger.

3. Orientation reflexes. Any new unexpected stimulus draws upon itself the removal of a person.

4. Play reflexes. This type of unconditioned reflexes is widespread in various representatives the animal kingdom and also has an adaptive value. Example: puppies playing,. hunt for each other, sneak up and attack their “enemy”. Consequently, in the process of playing, the animal creates models of possible life situations and carries out a kind of "preparation" for various life surprises.

Keeping their biological basis, children's play acquires new qualitative features - it becomes an active tool for understanding the world and, like any other human activity, acquires a social character. The game is the very first preparation for future work and creative activity.

The child's play activity appears from 3-5 months of postnatal development and underlies the development of his ideas about the structure of the body and the subsequent separation of himself from the surrounding reality. At 7-8 months, play activity acquires an “imitative or teaching” character and contributes to the development of speech, improvement of the child's emotional sphere and enrichment of his ideas about the surrounding reality. From the age of one and a half, the child's play becomes more and more difficult, in game situations the mother and other people close to the child are introduced, and thus, the foundations are created for the formation of interhuman, social relations.

In conclusion, it should be noted also sexual and parental unconditioned reflexes associated with the birth and feeding of offspring, reflexes that ensure the movement and balance of the body in space, and reflexes that maintain the homeostasis of the body.

Instincts. More complex, certainly reflex, activity are instincts, the biological nature of which is still unclear in its details. In a simplified form, instincts can be represented as a complex interconnected series of simple innate reflexes.

For the formation of a conditioned reflex, the following essential conditions are necessary:

The presence of a conditioned stimulus

The presence of unconditional reinforcement;

The conditioned stimulus should always somewhat precede the unconditioned reinforcement, that is, serve as a biologically significant signal, the conditioned stimulus in the strength of its effect should be weaker than the unconditioned stimulus; finally, for the formation of a conditioned reflex, a normal (active) functional state of the nervous system, first of all its leading part, the brain, is necessary. Any change can be a conditioned stimulus! Reward and punishment are powerful factors contributing to the formation of conditioned reflex activity. At the same time, we understand the words “encouragement” and “punishment” in a broader sense than simply “satisfying hunger” or “painful effects”. It is in this sense that these factors are widely used in the process of teaching and upbringing of a child, and every teacher and parent is well aware of their effective action. True, up to 3 years of age, for the development of useful reflexes in a child, “food reinforcement” is also of leading importance. However, then the leading role as a reinforcement in the development of useful conditioned reflexes acquires “verbal encouragement”. Experiments show that in children over 5 years of age, praise can be used to develop any beneficial reflex 100% of the time.

Thus, educational work, in its essence, is always associated with the development in children and adolescents, various conditioned reflex reactions or their complex interconnected systems.

The classification of conditioned reflexes is difficult due to their multiplicity. Distinguish exteroceptive conditioned reflexes formed during stimulation of exteroreceptors; interoceptive reflexes, formed when the receptors located in the internal organs are irritated; and proprioceptive, arising from irritation of muscle receptors.

Natural and artificial conditioned reflexes are distinguished. The former are formed when natural unconditioned stimuli act on the receptors, while the latter are formed when indifferent stimuli are acting. For example, the salivation of a child at the sight of his favorite sweets is a natural conditioned reflex, and the salivation of a hungry child at the sight of dinner dishes is an artificial reflex.

The interaction of positive and negative conditioned reflexes has essential for adequate interaction of the body with external environment... Such an important feature of a child's behavior as discipline is associated precisely with the interaction of these reflexes. In physical education lessons, to suppress self-preservation reactions and feelings of fear, for example, when doing gymnastic exercises on the uneven bars, students' defensive negative conditioned reflexes are inhibited and positive motor reflexes are activated.

A special place is occupied by conditioned reflexes for a time, the formation of which is associated with stimuli that are regularly repeated at the same time, for example, with food intake. That is why, by the time of eating, the functional activity of the digestive organs increases, which has a biological meaning. Such a rhythm of physiological processes underlies the rational organization of the daily routine of preschool and school children and is a necessary factor in the highly productive activity of an adult. Reflexes for time, obviously, should be attributed to the group of so-called trace conditioned reflexes. These reflexes are developed if unconditioned reinforcement is given 10-20 s after the final action of the conditioned stimulus. In some cases, it is possible to develop trace reflexes even after a 1-2 minute pause.

Imitation reflexes, which are also a kind of conditioned reflexes, are of great importance in a child's life. To develop them, it is not necessary to take part in the experiment, it is enough to be its “spectator”.

A child is born with a set of unconditioned reflexes. reflex arcs of which begin to form at the 3rd month prenatal development. So, the first sucking and breathing movements appear in the fetus precisely at this stage of ontogenesis, and the active movement of the fetus is observed in the 4-5th month of intrauterine development. By the time of birth, the child develops the majority of congenital unconditioned reflexes, which provide him with the normal functioning of the vegetative sphere, his vegetative “comfort”.

The possibility of simple food conditioned reactions, despite the morphological and functional immaturity of the brain, arises already on the first or second day, and by the end of the first month of development, conditioned reflexes are formed from the motor analyzer and the vestibular apparatus: motor and temporary. All these reflexes are very slowly formed, they are extremely gentle and easily inhibited, which, in fact, is associated with the immaturity of cortical cells and a sharp predominance of excitation processes over inhibitory ones and their wide irradiation.

From the second month of life, auditory, visual and tactile reflexes are formed, and by the 5th month of development, the child develops all the main types of conditioned inhibition. Teaching a child has an important role in improving conditioned reflex activity. The earlier the training started, i.e. e. the development of conditioned reflexes, the faster their subsequent formation proceeds.

By the end of the first year of development, the child relatively well distinguishes the taste of food, odors, shape and color of food. metov, distinguishes between voices and faces. The movements are significantly improved, some children begin to walk. The child tries to pronounce individual words ("mom", "dad", “ grandfather "," aunt ", “ uncle ”, etc.), and he has conditioned reflexes to verbal stimuli. Consequently, already at the end of the first year, the development of the second signaling system is in full swing and its joint activity with the first is being formed.

Speech development is a difficult task. It requires coordination of the activity of the respiratory muscles, muscles of the larynx, tongue, swelling and lips. Until this coordination is developed, the child pronounces many sounds and words incorrectly.

It is possible to facilitate the formation of speech by correct pronunciation of words and grammatical turns, so that the child constantly hears the patterns he needs. Adults, as a rule, when addressing a child, try to copy the sounds that the child utters, believing that in this way they can find with him “ mutual language”. This is a deep delusion. There is a huge distance between a child's understanding of words and the ability to pronounce them. Lack of required samples for imitations delays the formation of the child's speech.

The child begins to understand words very early, and therefore, for developed speech, “ talk ”with the child from the first days after his birth. When changing a baby's undershirt or diaper, shifting the baby or preparing him for feeding, it is advisable to do this not silently, but to address the baby with the appropriate words, naming your actions.

The first signaling system is the analysis and synthesis of direct, specific signals of objects and phenomena of the surrounding world, coming from visual, auditory and other receptors of the body and components

The second signal system is (only in humans) the connection between verbal signals and speech, the perception of words-audible, spoken (aloud or silently) and visible (while reading).

In the second year of the child's development, all types of conditioned reflex activity are improved and the formation of the second signal system continues, the vocabulary apas increases significantly (250-300 words); direct stimuli or their complexes begin to cause verbal reactions. If in a one-year-old child, conditioned reflexes to immediate stimuli are formed 8-12 ras faster than a word, then at two years the words acquire a signal value.

Of decisive importance in the formation of the child's speech and the entire second signaling system as a whole is the child's communication with adults, i.e. social environment and learning processes. This fact is further evidence of the decisive role of the environment in deployed and potential opportunities genotype. Children, deprived of a linguistic environment, communication with people, do not speak speech, moreover, their intellectual abilities remain at a primitive animal level. At the same time, the age from two to five is “critical” in mastering speech. There are cases that children abducted by wolves in early childhood and returned to human society after five years are able to learn to speak only to a limited extent, and those returned only after 10 years are not able to utter a single word.

The second and third years of life are distinguished by lively orienting and research activities. “At the same time,” writes MM Koltsova, “the essence of the orienting reflex of a child of this age can be more correctly characterized not by the question“ what is this ?”, but the question “what can be done with this ?”. The child reaches for every object, touches it, feels it, pushes it, tries to lift it, etc. ”.

Thus, the described age of the child is characterized by the “objective” nature of thinking, that is, by the decisive importance of muscle sensations. This feature is largely associated with the morphological maturation of the brain, since many motor cortical zones and zones of musculocutaneous sensitivity reach a sufficiently high functional usefulness by the age of 2 years. The main factors stimulating the maturation of these cortical zones are muscle contractions and high physical activity of the child. The limitation of his mobility at this stage of ontogenesis significantly slows down his mental and physical development.

The period up to three years is also characterized by the extraordinary ease of formation of conditioned reflexes to a variety of stimuli, including the size, severity, distance and color of objects. Pavlov considered these types of conditioned reflexes to be prototypes of concepts developed without words (“a grouped reflection of the phenomena of the external world in the brain ”).

A notable feature of the two - three year old child is the ease of developing dynamic stereotypes. Interestingly, each new stereotype is easier to develop. M. M. Koltsova writes: “Now not only the daily routine becomes important for the child: hours of sleep, wakefulness, food and walks, but also the sequence in putting on or taking off clothes or the order of words in a familiar fairy tale and song - everything gains meaning. Obviously, with insufficiently strong and still mobile nervous processes, children need stereotypes that facilitate adaptation to the environment. "

Conditioned connections and dynamic stereotypes in children under three years of age are unusually strong, so their alteration is always an unpleasant event for a child. An important condition in educational work at this time is respect to all generated stereotypes.

The age from three to five years is characterized by the further development of speech and the improvement of nervous processes (their strength, mobility and balance increase), the processes of internal inhibition become dominant, but delayed inhibition and conditioned brake are developed with difficulty. Dynamic stereotypes are still easy to develop. Their number increases every day, but their alteration no longer causes disturbances in higher nervous activity, which is due to the above functional changes. The orienting reflex to extraneous stimuli is longer and more intense than in school-age children, which can be used effectively for inhibition in children bad habits and skills.

Thus, in this period, truly inexhaustible opportunities open up before the creative initiative of the educator. Many outstanding teachers (D. A. Ushinsky, A. S. Makarenko) empirically considered the age from two to five to be especially responsible for the harmonious formation of all physical and mental capabilities of a person. Physiologically, this is based on the fact that conditioned connections and dynamic stereotypes that arise at this time are distinguished by exceptional strength and are carried by a person through his entire life. Moreover, their constant manifestation is not necessary, they can be inhibited for a long time, but under certain conditions they are easily restored, suppressing the conditioned connections developed later.

By the age of five to seven, the role of the signaling system of words increases even more, and children begin to speak freely. "A word at this age already has the meaning of a 'signal of signals', that is, it receives a generalizing meaning close to that which it has for an adult."

This is due to the fact that only by the age of seven years of postnatal development does the material substrate of the second signaling system functionally mature. In this regard, it is especially important for educators to remember that only by the age of seven can the word be effectively used to form conditional connections. Abuse of a word before this age without sufficient connection with immediate stimuli is not only ineffective, but also causes functional harm to the child, forcing the child's brain to work in non-physiological conditions.

The few physiological data that exist indicate that primary school age (from 7 to 12 years old) is a period of relatively “calm” development of higher nervous activity. The strength of the processes of inhibition and excitation, their mobility, balance and mutual induction, as well as a decrease in the strength of external inhibition, provide opportunities for the child's broad education. This is the transition "from reflex emotionality to the intellectualization of emotions"

However, only on the basis of teaching writing and reading does the word become an object of the child's consciousness, increasingly moving away from the images of objects and actions associated with it. A slight deterioration in the processes of higher nervous activity is observed only in the 1st grade in connection with the processes of adaptation to school. It is interesting to note that at primary school age, on the basis of the development of the second signaling system, the conditioned reflex activity of the child acquires a specific character characteristic only of humans. For example, during the development of autonomic and somato-motor conditioned reflexes in children, in a number of cases, a response is observed only to an unconditioned stimulus, and a conditioned one does not cause a reaction. So, if the subject was given a verbal instruction that after the call he will receive cranberry juice, then salivation begins only upon presentation of an unconditioned stimulus. Such cases of “non-formation” of the conditioned reflex appear the more often, the older the age of the subject, and among children of the same age - in the more disciplined and capable.

Verbal instruction significantly accelerates the formation of conditioned reflexes and in some cases does not even require unconditioned reinforcement: conditioned reflexes are formed in a person in the absence of direct stimuli. These features of conditioned reflex activity determine the enormous importance of verbal pedagogical influence in the process of teaching and educational work with younger schoolchildren.

Of particular importance for the teacher and educator is the following age period - adolescence (from 11 - 12 to 15-17 years). This is the time of great endocrine transformations in the body of adolescents and the formation of secondary sexual characteristics in them, which in turn affects the properties of higher nervous activity. The equilibrium of nervous processes is disturbed, excitement becomes more powerful, the increase in the mobility of nervous processes slows down, the differentiation of conditioned stimuli significantly worsens. The activity of the cortex is weakened, and at the same time the second signaling system. Figuratively, this period could be called “mountain gorge”.

All functional changes lead to mental imbalance of the adolescent (irascibility, “explosive” response even to minor irritations) and frequent conflicts with parents and teachers.

The adolescent's position, as a rule, is aggravated by the increasingly complicated demands on him from adults and, above all, from school. Unfortunately, today not every teacher takes into account the functional capabilities of children in their work, hence the difficulties that the teacher and most parents face in their communication with adolescents.

Only correct healthy regimen, a calm atmosphere, a solid program of classes, physical culture and sports, interesting extracurricular work, kindness and understanding on the part of adults are the main conditions for the transition period to pass without the development of functional disorders and related complications in the child's life.

Senior school age (15-18 years) coincides with the final morphological and functional maturation of all physiological systems human body... The role of cortical processes in the regulation of mental activity and physiological functions organism, the cortical processes that ensure the functioning of the second signaling system are of leading importance.

All properties of the main nervous processes reach the level of an adult. If at all the previous stages the conditions for the development of the child were optimal, then the higher nervous activity of older students becomes orderly and harmonious.

Higher nervous activity provides a person with adequate adaptation to the action of environmental factors, therefore, certain environmental influences cause various changes in higher nervous activity. Depending on the strength external influence changes in higher nervous activity can fluctuate within normal limits or go beyond them, becoming pathological.

Training sessions require intense work of the brain, and above all of its higher section - the cerebral cortex. Especially intensively work those cortical structures that are associated with the activity of the second signaling system and complex analytical and synthetic processes. Naturally, the load on the nerve elements should not exceed them. functionality otherwise, pathological changes in higher nervous activity are inevitable. If the training sessions at the school are organized according to hygienic requirements, then the changes in higher nervous activity do not go beyond the normal range. Usually at the end school day there is a weakening of the excitatory and inhibitory processes, a violation of induction processes and the relationship between the first and second signaling systems. These changes are especially noticeable in younger schoolchildren.

It is important to note that the inclusion of labor and physical education lessons in training sessions is accompanied by less pronounced changes in higher nervous activity at the end of the school day.

Of great importance for maintaining the normal working capacity of students is leisure after school: outdoor games, playing sports, walking on fresh air... Particularly important to preserve normal level higher nervous activity has night sleep... Insufficient duration of night sleep in schoolchildren leads to impaired analytic-synthetic activity of the brain, difficulty in the formation of conditioned reflex connections and an imbalance in the ratio between signaling systems. Compliance with the hygiene of night sleep normalizes the higher nervous activity, and all its disturbances observed as a result of inadequate sleep disappear.

Various chemicals, changing the functional state of the cortical cells and subcortical formations of the brain, significantly alter the higher nervous activity. Usually, the effect of chemicals on the higher nervous activity of an adult and a child is characterized by similar changes, but in children and adolescents, these changes are always more pronounced. Tea and coffee containing caffeine are far from harmless in this regard. In small doses, this substance enhances the cortical process of excitation, and in large doses, it causes its oppression and the development of transcendental inhibition. Large doses of caffeine also cause adverse changes in autonomic functions. Due to the fact that in children and adolescents, the processes of excitement somewhat prevail over the processes of inhibition, regardless of the type of their higher nervous activity, the use of strong tea and coffee is undesirable for them.

Nicotine has a significant effect on the higher nervous activity of children and adolescents. In small doses, it inhibits the inhibitory process and enhances excitation, and in large doses, it also inhibits the excitation processes. In a person, as a result of prolonged smoking, the normal ratio between the processes of excitation and inhibition, and the efficiency of cortical cells is significantly reduced.

A particularly destructive effect on the higher nervous activity of children and adolescents is the use of various drugs, including alcohol. Their effect on higher nervous activity has much in common, usually the first phase is characterized by a weakening of inhibitory processes, as a result of which excitement begins to prevail. This is characterized by an increase in mood and a short-term increase in performance. Then the excitatory process is gradually weakened and inhibitory develops, which often leads to the onset of heavy narcotic sleep.

In children, addiction to drugs and alcohol is usually not observed. In adolescents, however, it comes very quickly. Of all drug addiction, alcoholism is especially widespread in adolescents, which leads to a rapid degradation of the personality. The teenager becomes vicious, aggressive and rude. The transition from domestic drunkenness to alcoholism in adolescents takes about two years. Intoxication in adolescents is always characterized by more pronounced changes in higher nervous activity in comparison with adults: they very quickly experience inhibition of cortical processes. As a result, consciousness control over behavior is weakened, instincts begin to manifest sharply, which often brings adolescents to the dock. For teachers and educators to organize effective fight against alcoholism among adolescents, it is necessary to promote hygienic knowledge not only among adolescents, but also among parents, since, according to special studies, among juvenile offenders about 70% "got acquainted" with alcohol at the age of 10-11 and in most cases it was the fault of the parents ...

There is evidence that children aged 8 to 12 years received drinks from their parents for the first time in 65% of cases, at the age of 12-14 years - in 40%, at the age of 15-16 years - in 32%.

TO pathological changes higher nervous activity should include long-term chronic disorders that can be associated with both organic structural damage to nerve cells and functional disorders of their activity. Functional disorders higher nervous activity is called neuroses. Long-term functional disorders of higher nervous activity can then turn into organic, structural ones.

A teacher or educator often meets in their work with various manifestations of neurotic reactions in children and adolescents and therefore must have an idea of the nature of neuroses and the peculiarities of their course in children. of different ages... This knowledge will help them in time to notice the appearance of neurotic disorders of higher nervous activity in a child, and, after consulting a doctor, organize the optimal pedagogical correction of these disorders.

In modern pathology of higher nervous activity and psychiatry, three main forms of neuroses are distinguished:

neurasthenia,

obsessive-compulsive disorder

psychasthenia.

Neurasthenia - characterized by overstrain of the inhibitory or excitatory process in the cerebral cortex. Particularly often with neurasthenia, the processes of conditioned inhibition suffer. The cause of these disorders can be excessive mental and physical stress and various traumatic situations for the psyche. The manifestation of neurasthenia is different: there is a sleep disorder, loss of appetite, sweating, palpitations, headaches, low efficiency, etc. Patients become irritable, they are characterized by excessive fussiness and awkwardness of movements.

Obsessive-compulsive disorder - characterized by obsessive thoughts, fears, or drives. The cause of these neuroses is sometimes associated with overwork, illness and the peculiarities of higher nervous activity.

Hysteria - associated with the pathological predominance of the first signaling system over the second, the subcortex above the cerebral cortex, which is expressed in a significant weakening of the second signaling system. This neurosis is characterized by increased sensitivity to external irritation, extreme mood lability and increased suggestibility. There are known cases of hysterical blindness, deafness, paralysis, etc. Hysterical fits are widespread.

Psychasthenia is characterized by a predominance of the second signal system and weakness of the subcortex, therefore, patients are distinguished by the poverty of drives and emotions. They often have a tendency to pointless philosophizing.

It should be noted that adolescents and especially girls from 12 to 15 years old are characterized by a neurosis specific only for this age. This is anorexia nervosa associated with the idea of losing weight and manifests itself in a sharp restriction of oneself in food. This neurosis usually occurs in adolescents with high intellectual development but suffer from increased self-esteem.

Especially often neurotic disorders and various mental illness manifest in children aged 2 to 3.5 years and in puberty(from 12 to 15 years old). In this regard, during such periods, called crisis, teaching and educational work should be carried out especially carefully, since an inadequate attitude towards children in crisis or critical periods can provoke the development of mental illness.

Thus, for the normal development of children and adolescents at each separate stage of ontogenesis, it is necessary to create optimal conditions. It is possible to solve this paramount task only with close cooperation of specialists of different profiles: teachers, psychologists, physiologists, physicians and hygienists.

Age physiology / Yu. A. Ermalaev. - M .: Higher. shk. 1985.384 p., Ill.

Awakening thinking / F. Kliks. - M .: Progress. 1983.

Physiology of VND / L. G. Voronin. - M .: Higher. shk. 1979

Human physiology / under. ed. G.I. Kositsky. - F50 3rd ed., Rev. and additional, - M .: Medicine, 1985.544s., ill.

Human physiology / under. ed. N.V. Zimkina. - 3rd ed. - M .: Physical culture and sport. 1964.

The formation of a child's higher nervous activity is closely related to the dynamics of maturation of associative cortical structures. In communication with adults, a child learns certain knowledge, acquires new forms of relationship to the outside world. All this is based on the creation of new functional connections and syntheses. They allow you to master new forms of perception and memorization, types of thinking, ways of organizing movements. The structural basis of complex forms of behavior and psyche

the frontal and lower parietal areas of the cortex protrude, which in human ontogenesis increase in area by 9 times and in an adult they occupy about two-thirds of the entire surface of the neocortex. "

The construction of multi-link switches and connections of these zones of the cortex is a morphological expression of the fact that these formations are related to the most abstract and generalized forms of human perception and actions. In addition, in ontogeny, a person develops specific human cortical formations that have a special relation to the analysis and synthesis of stimuli associated with different aspects of speech activity (speech-motor, speech-auditory, speech-visual) (Fig. 82).

Congenital reflex activity. Already in newborns, a number of reflexes are observed with tactile irritation of certain receptive areas of the skin. The most important is the sucking reflex, which occurs when the mucous membrane of the tongue, lips, skin near the mouth and cheeks is irritated. Specific for newborns is the proboscis reflex - a tubular protrusion of the lips with a light touch around the mouth at the level of the gums, as well as the Babinsky reflex - dorsiflexion of the big toe and plantar flexion of all others when the sole of the foot is irritated.

Of the protective reflexes from the skin of a newborn, blinking reflexes should be mentioned, nasal - hand movement to irritate the nasal mucosa, ear - the same, when tickling the external auditory canal.

By the time of birth, pain and temperature receptors have already been formed, and when they are stimulated, the corresponding reflexes appear. At the same time, the receptors of the face are distinguished by the greatest excitability to painful irritations.

In newborns, multiple reflexes can be elicited from the vestibular apparatus. This is before

total installation labyrinth reflex of the head, installation reflex from the trunk to the head, cervical tonic reflex. These reflexes are clearly expressed in the first half of the year and by the end of the first year of life weaken and disappear.

From statokinetic reflexes for young children, rotational and post-rotational nystagmus, compensatory deviation of the head during rotation are characteristic. Stabilization of tonic and setting reflexes in children, which ensure a normal head position, maintenance of a sitting posture, standing, is possible due to the development of vestibular conditioned reflexes (1.5-2 months), and later by the analysis of vestibular signaling.

In newborns, a significant surface of the oral mucosa has a higher sensitivity than in adults - although the general taste sensitivity is reduced. Nevertheless, newborn babies distinguish between sweet, bitter, sour and salty. Moreover, sweet substances cause sucking movements, and the rest - a negative reaction: wrinkling the face, closing the eyes, curving the mouth, protruding lips and tongue.

The auditory system begins to function immediately after birth. To sounds in newborns, there are mainly general reactions in the form of startle and motor restlessness, which is accompanied by a change in respiratory and heart rhythm. Already newborn children can distinguish sounds that are one octave in height, perceive the difference in timbre, in its spatial arrangement.

The first reaction of a newborn to light stimuli is the pupillary reflex, which stabilizes only by 4-5 months. The orienting reflex to light stimuli, which at the beginning has a generalized character, also belongs to early visual reactions. Newborns cannot fix an object with their gaze. This ability is formed by 3-5 months, by which time the gaze fixation reaction appears. A typical orientation and exploratory reflex arises: turning the eyes and head towards the light source.

In newborns, eye movements are not coordinated, nystagmoid movements are observed. The gaze fixation mechanisms provide the appearance of a coordinated

vision. At this time, the ability to form conditioned reflexes to visual stimuli in the child is revealed.

The connection of the newborn with the outside world is carried out by a small number of innate reflexes, very imperfect, inaccurate, caused by both external and internal stimuli. Inborn reflexes of a person in the dynamics of his ontogenesis reveal their manifestation and complete maturation in different terms, which reflects the general biological evolutionary laws and determines, in turn, the dynamics of the formation of the higher nervous activity of the child.

Higher nervous activity of the childvth year after birth. The earliest form of individual adaptation in a newborn child is natural conditioned reflexes. The very first of them occur in the second week after birth with a strict feeding regime for the baby. In this case, as a rule, already 30 minutes before the next feeding, shifts appear in the internal environment of the child's body - an increase in the number of blood leukocytes, an increase in gas exchange, and then the awakening and anxiety of the child. This is a natural conditioned reflex "for a while", where stimulation of the receptors of internal organs acts as a signal, and food is a reinforcement. Almost simultaneously with this, a natural conditioned food reflex appears in the form of sucking movements in response to the "feeding position" (Bekhterev-Shchelovanov reflex). In the implementation of these reflexes, the main role is played by a complex of irritations from the skin, muscle and vestibular apparatus, and feeding is a reinforcement. For the formation of these reflexes, the beginning of the mother's breastfeeding of the newborn is important.

Adaptation of the child's body to a certain mode of sleep, wakefulness, feeding, etc. is the formation of systems of conditioned reflexes to successive

lexes of irritation (dynamic stereotypes). A child in the first year of life reacts strongly to a disturbance in sleep or nutrition, while changes in the environment are not so noticeable for him. By already by 9-10 months essential complexes of external stimuli are acquired for the child. Now, not only the regime is important for him, but also the external environment, certain people caring for him. This is determined by a large number of conditioned reflexes developed by this time to a variety of external signals.

The timing and rate of maturation of individual sensory systems determine the sequence of formation of various artificial conditioned reflexes.

During the 5-8th week, motor food and defense conditioned reflexes are developed from all sensory systems. Moreover, what older child, the less the number of combinations is required for the formation of a conditioned reflex and the earlier it is consolidated. All other things being equal, the formation of conditioned reflexes depends on the basis on which innate reflexes they are developed.

There is a certain pattern in the dynamics of the manifestation of conditioned reflex reactions. First stage characterized by the appearance of weakly expressed and unstable conditioned reactions. They are usually preceded by an orienting response. The vegetative components clearly appear in it: changes in respiration and cardiac activity. Second stage characterized by a more stable manifestation of specialized motor reactions with a simultaneous clear identification of vegetative components. Third stage differs in further specialization of the motor components of the conditioned reflex and the weakening of its vegetative components. The younger the child, the longer are all stages of the reflex development. In older children, the first stages are significantly reduced.

In the second half of life, the individual typological characteristics of higher nervous activity are clearly revealed. It is possible to single out a group of children in whom positive and inhibitory conditioned reflexes are quickly formed and consolidated. In the other group, positive conditioned connections are well formed, but differential inhibition is developed with difficulty. Finally, there is a group of children in whom positive conditioned reflexes are poorly developed and differentiations are not formed at all.

The individual characteristics of sleep, autonomic functions, and general development of the child are closely related to these features of the brain processes.

In parallel with the improvement of nervous processes, their properties are also developing - strength, mobility and balance. These properties can serve as the basis for the formation of individual characteristics of higher nervous activity.

Throughout the first year of life, a strict daily regimen is very important for the correct development of a child: sleep, wakefulness, nutrition and walks. A child of the first year of life reacts negatively to disturbances in sleep or nutrition, although changes in the situation and other external influences are of little significance for him, i.e., the stereotype of interoceptive conditioned reflexes is of greater importance than the stereotypes of external stimuli. It is only by the end of the first year that complexes of external stimuli acquire significant significance for the child.

By this time, inhibition of any reaction of the child is more reliable and easier to achieve by external inhibition, when the child's attention is switched with the help of an orienting reaction to a new stimulus. However, attempts to use various types of internal inhibition in educational purposes at this age are still unsuccessful.

On the basis of congenital and acquired

by imitating sound reactions to end of the first year of life appear first speech engineuse temporary connections.

Thus, during the first year of a child's life, the number of conditioned reflexes to immediate stimuli gradually increases. Initially, only vegetative conditioned reactions are formed, then motor reactions and, finally, speech-motor reactions appear. The presence of the latter does not yet indicate the appearance of verbal thinking, since there is still no distraction and generalization with the help of words. During this age period, only the elementary foundations of the second signaling system are laid.

Let's trace the dynamics of this process in more detail. At the age of 9-10 months, children's reactions are determined by stimuli emanating not from one object, but from the whole situation as a whole. Very often one of the components of such a simultaneous complex external stimulus is the word. Conditioned reflexes to words begin to appear in a child after 6 months of age (the first manifestations sensory speech). However, the word does not yet act as an independent signal; it acts only as part of complex stimuli as one of the components. So, for example, the questions: "Where is dad?" or "Where is mom?" cause the correct response of the child only under the condition of the simultaneous action of other stimuli: muscle, vestibular, visual and sound. It is worth changing at least one of these components (for example, voice and intonation), as the previous reaction disappears. But if, while maintaining all the previous components of the complex, replace the word with a similar sounding one, the reaction can still manifest itself. This means that at this age the word will still remain a weak component of the complex. The word initially has a secondary meaning and only gradually acquires the meaning of a strong component in a complex stimulus and, finally, an independent signal.

Under natural conditions, not a single complex stimulus is repeated in a strictly constant composition, while the most constant member of such a complex is the verbal one. Therefore, with the systematic repetition of a word as part of a complex of stimuli, the influence of the remaining variable components on the implementation of the reaction begins to weaken. First, the child's posture ceases to affect the performance of the reaction, and then the visual and auditory components of the complex stimulus. Only the word as the most constant component, regardless of other components, acquires a conditioned reflex action and gradually turns into a substitute for the entire complex. The "liberation" of a word from other components with which it was associated in a given complex stimulus is considered as a result of functional training of the nervous system. This process ends by the end of the first year of the child's life. A characteristic feature of the first words uttered (in the order of imitation) by a child is that they do not refer to a specific object, but to the entire situation as a whole. At this age, the child does not yet distinguish individual objects and objects of the external environment. Although a child of this age pronounces the words "mom" and "dad", it turns out that the dress of the mother and her bed are also "mom". And the child may not recognize the same mother with a new hairstyle, new clothes or in an unusual environment. So, for a child of this age the world seems to be still little dismembered in sound and visual relations. The first words are simply sound designations of certain objects and persons: first, the names of the things around the child, the names of toys, the names of adults, later - the images of objects, then - the names of parts of the body and face are perceived. The transformation of a word into an abstract signal denoting a set of objects occurs in the next age period.

Higher nervous activity in early childhood(1 - 3rdYes). For this

age characteristic is further morphological and functional maturation of the brain and coordinated management of the skeletonbushecological system. Walking and speech develops, hands are freed to manipulate objects. Conditions for active research activities are being created.

If at the age of one year, the child's behavior was determined mainly by the environment as a whole, then at the 2nd year of life, complexes of stimuli emanating from one object begin to be isolated. On their basis, images of individual objects arise. As a result of the child's actions with objects, they are isolated from the generalized undifferentiated world. The child reaches out with his hands to each object, feels it, pushes it, tries to pick it up, lick it with his tongue, etc. In this case, a lot of sensory signals (visual, muscle, gustatory, etc.) arise that are characteristic of this particular object.

A system of adequate actions with objects is gradually formed: the child begins to sit down on a chair, eat with a spoon, etc. If in a one-year-old child, food was the strongest unconditional reinforcement, then in the 2-3rd year of life the approximate ones are the most effective! defensive and game reinforcements. A lot of conditioned reflexes for relationships are formed.

In this period of development, systems of conditioned reflexes to stereotypes of external stimuli that follow each other in a certain time sequence acquire even greater importance. Of great importance is the sequence of the individual stages of washing, feeding, playing, dressing and undressing, the order of words in a fairy tale or song. Since children at this age have not yet sufficiently developed the strength and mobility of nervous processes that ensure switching from one type of activity to another, the need for formation is characteristic of children.

development of clear life stereotypes. Developing stereotypes is not difficult for a child, but changing the order of signals in a stereotype is an extremely difficult task. Therefore, for children under 3 years old it is necessary extremely respectful attitude install to all generated stereotypes. At this age, there is usually an intensive accumulation of the fund of speech-motor conditioned reflexes. By the end of the 2nd year, the child's vocabulary can be 200-400 words, and by the end of the 3rd year - 2000 words or more.

The formation of speech reactions is impossible without sound verbal imitation. In this case, a special role is played by establishing a connection between a word and the type of an object, its touch and other features. The physiological interpretation of the process of forming a connection between a word and various sensations in a child who first saw an object was given by I.M.Sechenov (1900).

For example, a child sees a Christmas tree, touches it, smells the needles, that is, receives a number of direct sensations. The word “fir tree” is a signal (“symbol of the first degree”, according to Sechenov), in which all these sensations are brought together, that is, an abbreviated sign of complex irritation. This system of reflexes between the components of the complex, which is nothing more than a complete understanding of the subject, I. M. Sechenov called "meaning in elementary form." After the child has met different trees, the word “tree” acquired a broader meaning (“symbol of the second order”), and the sensory image became less concrete. Then the word "tree" appears, covering a wide range of objects, and then an even more generalizing meaning of the word "plant".

In speech activity, you need to distinguish between understanding of speech (sensory speech) and its reproduction (motor speech). First, understanding of speech arises, then these two processes are closely linked. It turned out that in children under 3 years of age, the discrimination of speech sounds is closely related to the ability of subtle

manipulating fingers when feeling an object and muscle signals from the articulatory apparatus itself, arising when pronouncing words.

Active recognition of the surrounding world, operating with objects, typical for a child 2 3 years old, are closely related to "thinking in action." At first, the child's actions are chaotic and of the same type, but then, as a result of experience, they become purposeful and organized. Mastering actions with objects has a decisive influence on the formation of speech generalizations (inner speech). It was found that verbal signals are continuously enriched with new conditioned connections, which is the physiological basis of the generalization function. Moreover, the systems of conditioned connections developed at this age are particularly durable and sometimes retain their significance throughout the entire subsequent life of a person.

In the 2nd year of life, the child is combining words into sequential complexes - phrases and their automation. So far, such "speech circuits" are short. They consist of no more than 10 words.

Ф Using the Sechenov scheme, let us imagine the main stages in the development of the generalizing function of a word (according to M. M. Koltsova and N. I. Kasatkin, 1970).

/ degree of integration - the word replaces the sensory image of a certain object, that is, it is the equivalent of one specific object ("lala" - only this doll, the end of the 1st - the beginning of the 2nd year).

// degree of integration- the word replaces several sensual images of homogeneous objects ("lyalya" - refers to several dolls, the end of the 2nd year).

/// degree of integration - the word replaces a number of sensory images of dissimilar objects (“toys” are dolls, balls, and cubes). This degree of integration is achieved not earlier than the 3rd year.

IVdegree of integration - the word summarizes a number of generalizations of the previous degrees (for example, the word "thing" contains the generalization given by the word "toy", "clothing", "food", etc.). This degree of generalization develops in children at the 5th year of life.

Consequently, despite the increasing role of the word, the proportion of specific stimuli in child 3 years old still high enough: mNSwandering a childTobut it turns out to be mainly substantive.

Higher nervous activity in preschool age (from 3 to 6 years). This age is characterized by high stability of all types of internal braking. Extinction and differentiation of conditioned signals are generated faster, and the periods of holding the inhibitory state become longer. The general strengthening of nervous processes, and above all inhibition, is also manifested in the fact that children no longer perform a large number of manipulations, as it was before. The use of past experience and previously educated skills is gaining in importance. Stereotypes still play a significant role in a child's life. Moreover, these stereotypes are dominated by direct temporary connections. For example, children find it difficult or completely unable to count down (6, 5, 4, 3, 2, 1) and easily slip into the usual direct count.

f Feedbacks appear later than direct conditional connections, and only by school age the ratio between direct and feedback is leveled. Nevertheless, in children aged 5-7 years, the alteration of the stereotypes of stimuli is no longer difficult task and children perceive it as a game.

In 5-6-year-old children, during the development of conditioned reflexes, many MSI signal reactions are observed, and in 7-year-olds they occur only in 20% of cases. If a kindergarten teacher offers a game: for a certain signal to perform an action (for example, raise the left hand to the count of "five"), then the children will first perform

read it and in other words, before learning how to clearly follow the rules of the game.

Consequently, in 5-6-year-old children, there is still quite pronounced generalization, and the specialization of conditioned reflexes is achieved with sufficient difficulty.

By the age of 3-5, the generalizing meaning of the word is still based on one sign - the generality of actions that can be performed with objects. For example, a spoon is what they eat, furniture is what they sit or sleep on, etc. For this age, violent manifestations of emotions are typical, which, however, are unstable. Therefore, this period is called age affaTotivity. Children show attempts to assert themselves, attract attention, actively limit themselves from the environment. By the age of 6-7, it is possible to isolate general or group signs of objects and phenomena. In connection with the beginning of learning to read and write, the word acquires pronounced generalizing properties. At the age of 6-7 years, against the background of a general decrease in the affective sphere, begins predominate verbal thinking with inner speech.

I. M. Sechenov wrote about this: “This phase of mental evolution in the field of thinking begins as if with a major break (but, in essence, as we will soon see, this is not): the child thought, thought with sensory concrete, and suddenly objects of thought he does not have copies of reality, but some echoes of it, at first very close to the real order of things, but gradually moving away from their sources so much that apparently any connection between a sign or symbol and its sensory root is broken ”1.

Starting from the age of 6, the child is able to control his behavior on the basis of preliminary verbal-generalized instructions. By this age, the child is able to maintain a program of actions consisting of a series of movements. In children over 5 years old

^ Sechenov I. M. Collected op. Ed. AN SSSR, 1952.Vol. 1.S. 365-366.

on the progress of the development of conditional? Prior to this, the principle of maximization prevailed, in which even a minimal probability of reinforcement led to persistent repetition of this skill. Now, the child's behavior begins to be largely determined by the degree of probability of certain events in the environment. (atnoptimization cip),

In special electroencephalographic studies, the dynamics of functional maturation of the main cortical zones in young children was studied (T.P. Khrizman, 1978). It was found that the leading link in the organization of intercentral relations is not sensory, but associative parts of the neocortex - the inferior parietal and frontal zones. In children of the first year of life, the focuses of interrelated activity are the lower parietal zones associated with the occipital, temporal and motor centers of the cortex. In two-year-old children, the focuses of interrelated activity move to the frontal cortex, which enter into synchronous relationships with other centers of the cortex. In children 4-5 years old, there is an increase in intercentral interactions of the lower parietal lobes. At the later stages of ontogenesis (6-7 years), the intercentral connections of the frontal regions with other parts of the cortex again intensify (Fig. 83).

Intercentral relations are especially striking when studying the formation of a child's speech activity. In one-year-old children, only when a familiar word is recognized, the connections between the inferior parietal and temporal regions of the left hemisphere cortex are enhanced. In the second year of life, when recognizing a familiar word, the connections between the two associative areas - the lower parietal and frontal, also predominantly of the left hemisphere, strengthen. Such dynamics of rearrangements of electrical activity in the perception of words reflects the morphofunction

the rational maturity of the higher integrative systems of the child's brain.

Higher nervous activity in primary school age (6- 11 years). At this age, the nervous processes are characterized by sufficient strength and balance, all types of internal inhibition are well expressed. However, children still find it difficult to perform small and precise movements, although these abilities are improving very quickly. The mechanisms that determine active attention and concentration are not yet sufficiently developed. Rapid fatigue, sometimes accompanied by neurotic disorders, which can develop as a result of excessive academic load. The very fact of schooling has a significant impact on the development of the child's psyche, since the entire life of a schoolchild is radically rebuilt in comparison with his preschool childhood. Schooling six-year-old children accelerates the development of various mental properties in them compared to peers attending kindergartens.

At this age, the development of the cerebral cortex approaches the level of an adult, which is the most important factor in the formation of the higher nervous and mental functions of a child.

Children aged 6-11 years more clearly show the typological features of higher nervous activity. Children differ among themselves in terms of strength, balance and mobility of the processes of excitation and inhibition. A complete classification of the types of higher nervous activity has not yet been developed. In addition, the strength, mobility and balance of nervous processes change with age, therefore, the type of higher nervous activity in children can only be talked about very conditionally. Despite this, in educational work, it is required to take into account the characteristics of children:

NSandpersistent work, the development of individual properties of the highesterst activities can be changed in the desired toNSravlenii.

Rice 83 Scheme education mechanisms vosNSacceptance words in children vNSrocesse development (according to T. P Khrizman, 1978):

A- the level of receptive transformations; B - level of firne transcoding of a word; V - level of semantic analysis of the word; G - areas of the brain involved in the semantic analysis of the word; l frontal zones; m - motor, nt - lower parietal; in - temporal; occipital

Features of higher nervous activity in adolescence.

The period from 11 to 13 years for girls and from 13 to 15 years for boys is the first phase of adolescence. In adolescence, puberty occurs, it differs sharply from all other stages of a person's life. Changes in behavior are determined primarily by a general increase in the excitability of the central nervous system and a weakening of inhibition processes. Sometimes this leads to increased irritability, easy fatigue, sleep disorders.

In conditioned reflex activity, there is an increase in intersignal reactions, a deterioration in the differentiation of signals, and a wide irradiation of excitation. The latent periods of conditioned reactions increase. The speech of adolescents slows down, the answers become laconic and stereotyped, the formation of new conditioned connections to verbal signals is difficult. All these circumstances must be taken into account at school so that the teacher's requirements do not contradict the physiological characteristics of the adolescent's development. For some of them at this age,

pose certain difficulties in building a rich speech, logical inferences, memorizing a large amount of educational material.

The second phase of adolescence in girls is 13-15 years old, and in boys - 15-17 years old. This is the most critical phase in the development of adolescents. At this age, manifestations of mental imbalance are possible with abrupt transitions from violent delight to depression and vice versa, a sharply critical attitude towards the surrounding adults (relatives and teachers), extreme resentment, and girls have a tendency to cry. Frequent manifestations of negativism and irascibility. At this age, one of the tasks of teachers and parents is the development and training of cortical inhibition, the so-called education of "brakes".

The role of the second signaling system begins to increase again, the formation of conditioned reflexes to verbal signals is accelerated, and memory for abstract visual images improves.

f At the age of 15-17, mostly the formation of higher nervous activity is completed, it is characterized a high degree of functional excellence.

HISTOGENESIS OF THE NERVOUS SYSTEM

Neural tube inlay

Antenatal period

For 2-3 months. before birth, the fetus, responding with distinct movements to a sudden sound stimulus, with the repetition of the sound, gradually reduces the

Neonatal period

Neonatal period

Breast age

12 months

Cognition

2nd year

2nd year

2-3 years

3rd year

3rd year

3-5 years

5-7 years

5-7 years

5-7 years

5-7 years

Junior school age

Junior school age

Adolescence

Adolescence

Adolescence

Adolescence

Adolescence

Adolescence

Adolescence

Adolescence

Adolescence

Adolescence

Dominant

Features of the development of GNI in children.