Presentation on the topic "Features of human higher nervous activity" in biology in powerpoint format. This presentation for 8th grade students tells about the features of the higher nervous activity of a person that distinguish him from other creatures, as well as what cognitive processes are inherent in a person. Presentation author: Natalya Alekseevna Kuznetsova, biology teacher.

Fragments from the presentation

The main difference between man and other creatures

• Consciousness
• Speech
• Ability to work
• Public life

Consciousness

• Consciousness- the highest, peculiar only to man, form of mental reflection of objective reality.
• Human consciousness- the ability to separate oneself ("I") from other people and the environment ("not me"), an adequate reflection of reality. Consciousness is based on communication between people, develops as individual life experience is acquired, and is associated with speech (language).

Speech

Speech is a form of communication that has developed in the process of human historical evolution and is mediated by language.

Speech functions:

• Speech is the most perfect capacious, accurate and high-speed means of communication between people.
• Speech serves as a tool for the implementation of many mental functions, raising them to the level of clear awareness and opening up the possibility of arbitrarily regulating and controlling mental processes.
• Speech provides an individual with a communication channel for obtaining information from the universal human socio-historical experience.

Work

• Labor is a fundamental form of human activity, in the process of which the entire set of objects necessary for satisfying needs is created.
• 
  In the process of evolution, a person has developed adaptations to work, the thumb is opposed to the rest.

Man is a biosocial being

Life, development, upbringing in society is a key condition for the normal development of a person, transformation into a personality. There are cases when people from birth lived outside of human society, were brought up among animals. In such cases, of the two principles, social and biological, only one remained in man - biological. Such people acquired the habits of animals, lost the ability to articulate speech, lagged far behind in mental development, and even after returning to human society did not take root in it.

cognitive processes

Cognition- the process of human activity, the main content of which is the reflection of objective reality in his mind, and the result is the acquisition of new knowledge about the world around.

• The first step in knowing FEELING The immediate reaction of the nervous system to the fact of reality (irritation). For example: we hear the singing of a nightingale, i.e. sound waves of different lengths irritate the nerve cells of the ear, and the signals from the neuron go to the brain.
• At the second stage of cognition, the mechanism PERCEPTIONS Primary holistic analysis of nerve signals in the brain. If the sensation of sound is just a chaotic vibration, then PERCEPTION puts the chaos into a melody.
• The third step can be considered THINKING Sensual or logical analysis of a fact. Here, the brain already uses the existing experience, includes operations of comparison, analysis, generalization.

Thinking operations:

• Analysis
• Synthesis
• Comparison
• Generalization
• abstraction

MEMORY

Memory- this is the memorization, preservation and subsequent reproduction by a person of his experience. Without memory, learning, thinking, and skill cannot take place.

How to remember a lot, quickly and reliably

• It is very important to focus on what you want to learn and not be distracted.
• Tell other people what you have read.
• When reading in a whisper, you should not pronounce the words, or mentally pronounce what you are reading at the moment.
• Write down what you read
• The most important text for you is best read in the morning, when the brain works at its best, or in the afternoon, if you wake up hard.
• Repeat what has been learned. For the first time, update everything in memory 40 minutes after memorization. Repeat on the same day, 2-3 times. Then, if you remember, the next day one or two repetitions. And then, one repetition with an interval of 7-10 days.

Imagination

Every person has an imagination. Images of the imagination are fixed with the help of speech and can be transmitted to other people in the form of artistic images or scientific assumptions, which will then be analyzed by logical thinking and used in building ideas when creating new things.

Distinguish between active and passive imagination.

• Active imagination allows a person to imagine what will be the result before starting his work. These images allow you to bring the product to the required level, whether it is a homemade product in the hands of a child or a spaceship in the drawings of the general designer.
• Active imagination should be distinguished from passive imagination, which replaces active actions.

The first and second signal systems and their interaction

• Pavlov called the conditioned reflex activity of the cerebral cortex the signal activity of the brain.
• 1 signal system - signals entering the brain, which are caused by objects and phenomena that act on the senses (resulting in sensations, perceptions, ideas). It is found in humans and animals.
• 2 signal system - Word. Only man has.
• Both signaling systems are in constant interaction. If the signals of the second signal system (words) do not have support in the first signal system (do not reflect what was received through it), then they become incomprehensible. So, a word in a foreign language that we do not know does not tell us anything, so as behind this word there is no concrete content for us.

• Size: 4.9 MB
• Number of slides: 98

Description of the presentation Presentation of the physiology of GNI and SS children on slides

Age features of the development of the central nervous system, the physiology of higher nervous activity and sensory systems. Part

Higher nervous activity is the activity of the higher parts of the central nervous system, which ensures the most perfect adaptation of animals and humans to the environment. Higher nervous activity includes gnosis (cognition), praxis (action), speech, memory and thinking, consciousness, etc. The behavior of the organism is the crowning result of higher nervous activity. Mental activity is an ideal, subjectively perceived activity of the body, carried out with the help of neurophysiological processes. The psyche is the property of the brain to carry out mental activity. Consciousness is an ideal, subjective reflection of reality with the help of the brain.

History of science For the first time, the idea of ​​the reflex nature of the activity of the higher parts of the brain was broadly and in detail formulated by the founder of Russian physiology, I. M. Sechenov, and presented in the work "Reflexes of the Brain". The ideas of I. M. Sechenov were further developed in the works of another outstanding Russian physiologist, I. P. Pavlov, who opened the way for an objective experimental study of the functions of the cerebral cortex, and also developed the method of conditioned reflexes and created a holistic doctrine of higher nervous activity. The first generalizations concerning the essence of the psyche can be found in the works of ancient Greek and Roman scientists (Thales, Anaximenes, Heraclitus, Democritus, Plato, Aristotle, Epicurus, Lucretius, Galen). Of exceptional importance for the development of materialistic views in the study of the physiological foundations of mental activity was the substantiation by Rene Descartes (1596-1650) of the reflex mechanism of the relationship between the organism and the environment. On the basis of the reflex mechanism, Descartes tried to explain the behavior of animals and simply the automatic actions of a person.

An unconditioned reflex is a relatively constant, species-specific, stereotypical, genetically fixed reaction of the body to internal or external stimuli, carried out through the central nervous system. Hereditarily fixed unconditioned reflexes can arise, be inhibited and modified in response to a wide variety of stimuli that an individual encounters. A conditioned reflex is a reaction of the organism to a stimulus developed in ontogenesis, previously indifferent to this reaction. The conditioned reflex is formed on the basis of the unconditioned (innate) reflex.

IP Pavlov at one time divided unconditioned reflexes into three groups: simple, complex and most complex unconditioned reflexes. Among the most complex unconditioned reflexes, he singled out the following: 1) individual - food, active and passive-defensive, aggressive, freedom reflex, exploratory, game reflex; 2) specific - sexual and parental. According to Pavlov, the first of these reflexes ensure the individual self-preservation of the individual, the second - the preservation of the species.

Vital ● Food ● Drinking ● Defensive ● Regulation of sleep - wakefulness ● Energy savings Role-playing (zoosocial) ● Sexual ● Parental ● Emotional ● Resonance, "empathy" ● Territorial ● Hierarchical Self-development ● Research ● Imitation ● Game ● Overcoming resistance, freedom. The most important unconditioned reflexes of animals (according to P. V. Simonov, 1986, amended) Note: due to the peculiarities of the terminology of that time, instincts are called unconditioned reflexes (these concepts are close, but not identical).

Features of the organization of the unconditioned reflex (instinct) An instinct is a complex of motor acts or a sequence of actions characteristic of an organism of a given species, the implementation of which depends on the functional state of the animal (determined by the dominant need) and the current situation. External stimuli that make up the starting situation are called "key stimuli". The concept of "drive and drive reflex" according to Yu. Konorsky Drive reflexes are a state of motivational excitation that occurs when the "center of the corresponding drive" is activated (for example, hunger excitation). Drive is hunger, thirst, rage, fear, etc. According to the terminology of Y. Konorsky, drive has an antipode - “antidrive”, i.e. such a state of the body that occurs after satisfaction of a certain need, after the drive reflex is completed.

Many human actions are based on sets of standard behavior programs that we inherited from our ancestors. They are influenced by the characteristics of physiological processes, which can take place in different ways depending on the age or gender of the person. Knowledge of these factors greatly facilitates the understanding of the behavior of other people, and allows the teacher to more effectively organize the learning process. Features of human biology allow him to use standard behavior programs that contribute to survival in conditions from the far north to tropical forests and from sparsely populated deserts to giant megacities

How many instinctive programs do children have? Children have hundreds of instinctive programs that ensure their survival in the early stages of life. True, some of them have lost their former meaning. But some programs are vital. So, a complex program that works on the principle of imprinting is responsible for the development of a language by a child.

Why are the pockets of children full of all sorts of things? In childhood, people behave like typical foragers. The child is still crawling, but already notices everything, picks up and pulls into the mouth. Having become older, he collects all sorts of things in various places for a significant part of the time. Their pockets are stuffed with the most unexpected items - nuts, bones, shells, pebbles, ropes, often mixed with bugs, corks, wires! All this is a manifestation of the same ancient instinctive programs that made us human. In adults, these programs often manifest themselves in the form of cravings for collecting a wide variety of items.

The structure of the nervous tissue Nervous tissue: The neuron is the main structural and functional unit of the nervous tissue. Its functions are related to the perception, processing, transmission and storage of information. Neurons consist of a body and processes - a long one, along which excitation goes from the cell body - an axon and dendrites, along which excitation goes to the cell body.

The nerve impulses that a neuron generates propagate along the axon and are transmitted to another neuron or to an executive organ (muscle, gland). The complex of formations serving for such transmission is called a synapse. The neuron that transmits a nerve impulse is called presynaptic, and the one that receives it is called postsynaptic.

The synapse consists of three parts - the presynaptic ending, the postsynaptic membrane and the synaptic cleft located between them. Presynaptic endings are most often formed by an axon that branches, forming specialized extensions at its end (presynapse, synaptic plaques, synaptic buttons, etc.). The structure of the synapse: 1 - presynaptic ending; 2 - postsynaptic membrane; 3 - synoptic gap; 4 - vesicle; 5 - endoplasmic reticulum; 6 - mitochondrion. The internal structure of the neuron The neuron has all the organelles characteristic of a normal cell (endoplasmic reticulum, mitochondria, Golgi apparatus, lysosomes, ribosomes, etc.). One of the main structural differences of neurons from other cells is associated with the presence in their cytoplasm of specific formations in the form of lumps and grains of various shapes - the Nissl substance (tigroid). In nerve cells, the Golgi complex is also well developed, there is a network of fibrillar structures - microtubules and neurofilaments.

Neuroglia, or simply glia, is a collection of supporting cells of the nervous tissue. It makes up about 40% of the volume of the CNS. The number of glial cells is on average 10-50 times greater than that of neurons. Types of neuroglial cells:] - ependymocytes; 2 - protoplasmic astrocytes; 3 - fibrous astrocytes; 4 - oligodendrocytes; 5 - microglia Ependymocytes form a single layer of ependymal cells, actively regulate the metabolism between the brain and blood, on the one hand, and cerebrospinal fluid and blood, on the other. Astrocytes are located in all parts of the nervous system. These are the largest and most numerous of the glial cells. Astrocytes are actively involved in the metabolism of the nervous system. Oligodendrocytes are much smaller than astrocytes and perform a trophic function. analogues of oligodendrocytes are Schwann cells, which also form sheaths (both myelinated and unmyelinated) around the fibers. Microglia. Microgliocytes are the smallest of the glial cells. Their main function is protective.

The structure of nerve fibers A - myelin; B - unmyelinated; I - fiber; 2 - myelin layer; 3 - the nucleus of the Schwann cell; 4 - microtubules; 5 - Neurofilaments; 6 - mitochondria; 7 - connective tissue membrane Fibers are divided into myelinated (pulp) and non-myelinated (non-pulp). Unmyelinated nerve fibers are covered only by a sheath formed by the body of the Schwann (neuroglial) cell. The myelin sheath is a double layer of the cell membrane and, in its chemical composition, is a lipoprotein, i.e., a combination of lipids (fat-like substances) and proteins. The myelin sheath effectively provides electrical insulation to the nerve fiber. It consists of cylinders 1.5-2 mm long, each of which is formed by its own glial cell. The cylinders separate the nodes of Ranvier - non-myelinated sections of the fiber (their length is 0.5 - 2.5 microns), which play an important role in the rapid conduction of the nerve impulse. On top of the myelin sheath, the pulp fibers also have an outer sheath - the neurilemma, formed by the cytoplasm and the nucleus of neuroglial cells.

Functionally, neurons are divided into sensitive (afferent) nerve cells that perceive stimuli from the external or internal environment of the body. , motor (efferent) controlling contractions of striated muscle fibers. They form neuromuscular synapses. Executive neurons control the work of internal organs, including smooth muscle fibers, glandular cells, etc., between them there may be intercalary neurons (associative) connection between sensory and executive neurons. The work of the nervous system is based on reflexes. Reflex - the body's response to irritation, which is carried out and controlled by the nervous system.

The reflex arc is the path along which excitation passes during a reflex. It consists of five departments: receptor; a sensitive neuron that transmits an impulse to the central nervous system; nerve center; motor neuron; a working organ that reacts to the received irritation.

The laying of the nervous system occurs in the 1st week of intrauterine development. The greatest intensity of division of nerve cells of the brain falls on the period from 10 to 18 weeks of intrauterine development, which can be considered a critical period for the formation of the central nervous system. If the number of nerve cells in an adult is taken as 100%, by the time the child is born, only 25% of the cells have been formed, by 6 months - 66%, and by the year - 90-95%.

The receptor is a sensitive formation that transforms the energy of the stimulus into a nervous process (electrical excitation). The receptor is followed by a sensory neuron located in the peripheral nervous system. The peripheral processes (dendrites) of such neurons form a sensory nerve and go to the receptors, while the central processes (axons) enter the CNS and form synapses on its intercalary neurons. The nerve center is a group of neurons necessary for the implementation of a certain reflex or more complex forms of behavior. It processes information that comes to it from the sense organs or from other nerve centers and in turn sends commands to the executive neurons or other nerve centers. It is thanks to the reflex principle that the nervous system provides the processes of self-regulation.

Scientists who made a great contribution to the development of the conditioned reflex theory of I. P. Pavlov: L. A. Orbeli, P. S. Kupalov, P. K. Anokhin, E. A. Asratyan, L. G. Voronin, Yu. Konorsky and many others . Rules for the development of a classical conditioned reflex In combinations, an indifferent stimulus (for example, the sound of a bell) must be followed by a significant stimulus (for example, food). After several combinations, an indifferent stimulus becomes a conditioned stimulus—that is, a signal that predicts the appearance of a biologically significant stimulus. The significance of the stimulus can be associated with any motivation (hunger, thirst, self-preservation, care for offspring, curiosity, etc.)

Examples of some classic conditioned reflexes currently used in laboratory conditions in animals and humans: - Salivary reflex (combination of any SS with food) - manifests itself in the form of salivation in response to SS. — Various defensive reactions and reactions of fear (a combination of any CA with electric pain reinforcement, a sharp loud sound, etc.) – manifests itself in the form of various muscle reactions, changes in heart rate, galvanic skin response, etc. — Blinking reflexes (a combination of any US with exposure to the eye area with a jet of air or a click on the bridge of the nose) - manifested in blinking of the eyelid - The reaction of aversion to food (combination of food as a US with artificial effects on the body that cause nausea and vomiting) - manifests itself in the rejection of the corresponding type of food despite hunger. - and etc.

Types of conditioned reflexes Natural are called conditioned reflexes that are formed to stimuli that are natural, necessarily accompanying features, properties of the unconditioned stimulus on the basis of which they are developed (for example, the smell of food during its preparation). Conditioned reflexes are called artificial, which are formed to stimuli that, as a rule, are not directly related to the unconditioned stimulus that reinforces them (for example, a light stimulus reinforced by food).

According to the efferent link of the reflex arc, in particular, according to the effector, on which reflexes appear: vegetative and motor, instrumental. etc. Instrumental conditioned reflexes can be formed on the basis of unconditioned reflex motor reactions. For example, motor defensive conditioned reflexes in dogs are developed very quickly, first in the form of a general motor reaction, which then quickly specializes. Conditioned reflexes for time are special reflexes that are formed with the regular repetition of an unconditioned stimulus. For example, feeding a baby every 30 minutes.

Dynamics of the main nervous processes according to Pavlov The spread of the nervous process from the central focus to the surrounding area is called irradiation of excitation. The opposite process - restriction, reduction of the zone of the focus of excitation is called the concentration of excitation. The processes of irradiation and concentration of nervous processes form the basis of induction relationships in the central nervous system. Induction is the property of the main nervous process (excitation or inhibition) to cause around itself and after itself the opposite effect. Positive induction is observed when the focus of the inhibitory process immediately or after the cessation of the inhibitory stimulus creates an area of ​​increased excitability in the area surrounding it. Negative induction occurs when the focus of excitation creates around itself and after itself a state of reduced excitability. Scheme of experience for studying the movement of nervous processes: + 1 - positive stimulus (cassette); -2 - -5 - negative stimuli (kasalki)

Types of inhibition according to IP Pavlov: 1. External (unconditional) inhibition. - permanent brake - fading brake 2. Outrageous (protective) braking. 3. Internal (conditional) inhibition. - extinctive inhibition (extinction) - differential inhibition (differentiation) - conditional brake - delay inhibition

Dynamics of conditioned reflex activity External (unconditioned) inhibition is the process of an emergency weakening or cessation of individual behavioral reactions under the action of stimuli coming from the external or internal environment. The reason may be various conditioned reflex reactions, as well as various unconditioned reflexes (for example, an orienting reflex, a defensive reaction - fear, fear). Another type of innate inhibitory process is the so-called marginal inhibition. It develops with prolonged nervous excitement of the body. Conditional (internal) inhibition is acquired and manifests itself in the form of delay, extinction, elimination of conditioned reactions. Conditioned inhibition is an active process in the nervous system, developing, like conditioned excitation, as a result of production.

Fading inhibition develops in the absence of reinforcement of the conditioned signal by the unconditioned one. Extinctive inhibition is often referred to as extinction. A conditioned brake is formed when a combination of a positive conditioned stimulus and an indifferent one is not reinforced. During retardation inhibition, reinforcement is not canceled (as in the types of inhibition considered above), but is significantly removed from the onset of the action of the conditioned stimulus.

In response to repeated or monotonous stimuli, internal inhibition inevitably develops. If this stimulation continues, then sleep occurs. The transitional period between wakefulness and sleep is called the hypnotic state. IP Pavlov divided the hypnotic state into three phases, depending on the size of the area of ​​the cerebral cortex covered by inhibition and the corresponding reactivity of various brain centers in the process of realization of conditioned reflexes. The first of these phases is called equalizing. At this time, strong and weak stimuli evoke the same conditioned responses. The paradoxical phase is characterized by deeper sleep. In this phase, weak stimuli cause a more intense response than strong ones. The ultraparadoxical phase means an even deeper sleep, when only weak stimuli evoke a response, and strong ones lead to an even greater spread of inhibition. These three phases are followed by deep sleep.

Anxiety is a property determined by the degree of anxiety, concern, emotional tension of a person in a responsible and especially threatening situation. Emotional excitability is the ease of occurrence of emotional reactions to external and internal influences. Impulsivity characterizes the speed of response, decision-making and execution. Rigidity and lability determine the ease and flexibility of a person's adaptation to changing external influences: the one who is difficult to adapt to a changed situation, who is inert in behavior, does not change his habits and beliefs, is registrable; labile is the one who quickly adapts to a new situation.

CENTRAL NERVOUS SYSTEM The central nervous system includes those parts of the nervous system whose neuron bodies are protected by the spine and skull - the spinal cord and brain. In addition, the brain and spinal cord are protected by membranes (hard, arachnoid and soft) of connective tissue. The brain is anatomically divided into five sections: ♦ medulla oblongata; ♦ hindbrain formed by the pons and cerebellum; ♦ midbrain; ♦ diencephalon formed by the thalamus, epithalamus, hypothalamus; ♦ telencephalon, consisting of cerebral hemispheres, covered with bark. Under the cortex are the basal ganglia. The medulla oblongata, the pons and the midbrain are the stem structures of the brain.

The brain is located in the brain region of the skull, which protects it from mechanical damage. Outside, it is covered with meninges with numerous blood vessels. The mass of the brain in an adult reaches 1100 - 1600 g. The brain can be divided into three sections: posterior, middle and anterior. The posterior section includes: the medulla oblongata, the bridge and the cerebellum, and the anterior section includes the diencephalon and cerebral hemispheres. All departments, including the cerebral hemispheres, form the brain stem. Inside the cerebral hemispheres and in the brain stem there are cavities filled with fluid. The brain consists of white matter in the form of conductors connecting parts of the brain to each other, and gray matter located inside the brain in the form of nuclei and covering the surface of the hemispheres and cerebellum in the form of a cortex.

The longitudinal fissure of the cerebrum divides the cerebrum into two hemispheres - right and left. The cerebral hemispheres are separated from the cerebellum by a transverse fissure. In the cerebral hemispheres, three phylogenetically and functionally different systems are combined: 1) the olfactory brain, 2) the basal nuclei, 3) the cerebral cortex (cloak).

The cerebral cortex is a multilayer neural tissue with many folds with a total area in both hemispheres of approximately 2200 cm 2, its volume corresponds to 40% of the mass of the brain, its thickness ranges from 1.3 to 4.5 mm, and the total volume is 600 cm 3 The composition of the cerebral cortex includes 10 9 - 10 10 neurons and many glial cells. The cortex is divided into 6 layers (I-VI), each of which consists of pyramidal and stellate cells. In layers I - IV, the perception and processing of signals entering the cortex in the form of nerve impulses occurs. The efferent pathways leaving the cortex are formed mainly in the V-VI layers. Structural and functional characteristics of the cerebral cortex

The occipital lobe receives sensory input from the eyes and recognizes shape, color, and movement. The frontal lobe controls muscles throughout the body. The area of ​​motor associations of the frontal lobe is responsible for the acquired motor activity. The anterior center of the visual field controls voluntary eye scanning. Broca's center translates thoughts to external, and then internal speech. The temporal lobe recognizes the main characteristics of sound, its pitch and rhythm. The area of ​​​​auditory associations ("Wernicke's center" - temporal lobes) understands speech. The vestibular region in the temporal lobe receives signals from the semicircular canals of the ear and interprets the senses of gravity, balance, and vibration. The olfactory center is responsible for the sensations caused by smell. All of these areas are directly related to the memory centers in the limbic system. The parietal lobe recognizes touch, pressure, pain, heat, cold without visual sensations. It also contains the taste center responsible for the sensation of sweet, sour, bitter and salty.

Localization of functions in the cerebral cortex Sensory zones of the cortex The central sulcus separates the frontal lobe from the parietal, the lateral sulcus separates the temporal lobe, the parietal-occipital sulcus separates the occipital lobe from the parietal. In the cortex, sensitive, motor zones and associative zones are distinguished. Sensitive zones are responsible for the analysis of information coming from the sense organs: occipital - for vision, temporal - for hearing, smell and taste, parietal - for skin and joint-muscular sensitivity.

And each hemisphere receives impulses from the opposite side of the body. The motor zones are located in the posterior regions of the frontal lobes, from here come the commands for contraction of the skeletal muscles. Associative zones are located in the frontal lobes of the brain and are responsible for the development of programs for behavior and control of human activities; their mass in humans is more than 50% of the total mass of the brain.

The medulla oblongata is a continuation of the spinal cord, performs reflex and conduction functions. Reflex functions are associated with the regulation of the work of the respiratory, digestive and circulatory organs; here are the centers of protective reflexes - coughing, sneezing, vomiting.

The bridge connects the cerebral cortex with the spinal cord and cerebellum, and performs mainly a conductive function. The cerebellum is formed by two hemispheres, externally covered with a bark of gray matter, under which is white matter. The white matter contains nuclei. The middle part - the worm connects the hemispheres. Responsible for coordination, balance and affects muscle tone.

Three parts are distinguished in the diencephalon: the thalamus, the epithalamus, which includes the pineal gland, and the hypothalamus. The subcortical centers of all types of sensitivity are located in the thalamus; excitation from the sense organs comes here. The hypothalamus contains the highest centers of regulation of the autonomic nervous system, it controls the constancy of the internal environment of the body.

The structure and functions of the brain Here are the centers of appetite, thirst, sleep, thermoregulation, i.e., the regulation of all types of metabolism is carried out. Neurons of the hypothalamus produce neurohormones that regulate the functioning of the endocrine system. In the diencephalon there are also emotional centers: centers of pleasure, fear, aggression. It is part of the brain stem.

The structure and functions of the brain The forebrain consists of the cerebral hemispheres connected by the corpus callosum. The surface is formed by the bark, the area of ​​which is about 2200 cm 2. Numerous folds, convolutions and furrows significantly increase the surface of the bark. The human cortex has from 14 to 17 billion nerve cells arranged in 6 layers, the thickness of the cortex is 2 - 4 mm. Accumulations of neurons in the depths of the hemispheres form subcortical nuclei.

A person is characterized by a functional asymmetry of the hemispheres, the left hemisphere is responsible for abstract-logical thinking, speech centers are also located there (Brock's center is responsible for pronunciation, Wernicke's center for understanding speech), the right hemisphere is responsible for figurative thinking, musical and artistic creativity.

The most important parts of the brain, which form the limbic system, are located along the edges of the cerebral hemispheres, as if “surrounding” them. The most important structures of the limbic system: 1. Hypothalamus 2. Amygdala 3. Orbito-frontal cortex 4. Hippocampus 5. Mamillary bodies 6. Olfactory bulbs and olfactory tubercle 7. Septum 8. Thalamus (anterior group of nuclei) 9. Belt gyrus (etc. .)

Schematic diagram of the limbic system and thalamus. 1 - cingulate gyrus; 2- frontotemporal and subcallosal cortex; 3 - orbital cortex; 4 - primary olfactory cortex; 5 - almond-shaped complex; 6 - hippocampus (not shaded) and hippocampal gyrus; 7 - thalamus and mastoid bodies (according to D. Plug) Limbic system

The thalamus acts as a "distribution station" for all sensations entering the brain, except for olfactory ones. It also transmits motor impulses from the cerebral cortex through the spinal cord to the musculature. In addition, the thalamus recognizes sensations of pain, temperature, light touch and pressure, and is also involved in emotional processes and memory.

Nonspecific nuclei of the thalamus are represented by the median center, paracentral nucleus, central medial and lateral, submedial, ventral anterior, parafascicular complexes, reticular nucleus, periventricular and central gray mass. The neurons of these nuclei form their connections according to the reticular type. Their axons rise to the cerebral cortex and contact with all its layers, forming not local, but diffuse connections. Connections from the RF of the brain stem, hypothalamus, limbic system, basal ganglia, and specific nuclei of the thalamus come to nonspecific nuclei.

The hypothalamus controls the functioning of the pituitary gland, normal body temperature, food intake, sleep and wakefulness. It is also the center responsible for behavior in extreme situations, manifestations of rage, aggression, pain and pleasure.

The amygdala provides the perception of objects as having one or another motivational-emotional meaning (terrible / dangerous, edible, etc.), and it provides both innate reactions (for example, an innate fear of snakes) and those acquired in the course of the individual's own experience.

The amygdala is associated with areas of the brain responsible for processing cognitive and sensory information, as well as with areas related to combinations of emotions. The amygdala coordinates reactions of fear or anxiety caused by internal signals.

The hippocampus uses sensory information from the thalamus and emotional information from the hypothalamus to form short-term memory. Short-term memory, by activating the nerve networks of the hippocampus, can then move into "long-term storage" and become long-term memory for the entire brain. The hippocampus is the central part of the limbic system.

Temporal bark. Participates in the capture and storage of figurative information. Hippocampus. Acts as the first point of convergence of conditioned and unconditioned stimuli. The hippocampus is involved in fixing and retrieving information from memory. reticular formation. It has an activating effect on the structures involved in the fixation and reproduction of memory traces (engrams), and is also directly involved in the processes of engram formation. thalamocortical system. Helps organize short-term memory.

The basal ganglia direct nerve impulses between the cerebellum and the anterior lobes of the brain and thereby help control body movements. They contribute to the control of fine motor skills of the facial muscles and eyes, reflecting emotional states. The basal ganglia are connected to the anterior lobes of the brain through the substantia nigra. They coordinate the thought processes involved in planning the order and coherence of upcoming actions in time.

The orbito-frontal cortex (located on the lowest anterior side of the frontal lobe) seems to provide self-control over emotions and the complex manifestations of motivations and emotions in the psyche.

THE NERVOUS CIRCUITS OF DEPRESSION: THE LORD OF MOOD People with depression are characterized by general lethargy, depressed mood, slow reactions, and memory problems. It seems that brain activity is significantly reduced. At the same time, manifestations such as anxiety and sleep disturbances suggest that some areas of the brain, on the contrary, are hyperactive. With the help of visualization of the brain structures most affected by depression, it was found that the reason for this mismatch of their activity lies in the dysfunction of a tiny area - field 25. This field is directly related to such departments as the amygdala, which is responsible for the development of fear and anxiety, and the hypothalamus that triggers the stress response. In turn, these departments exchange information with the hippocampus (the center of memory formation) and the insular lobe (involved in the formation of perceptions and emotions). In individuals with genetic characteristics associated with reduced serotonin transport, the size of field 25 is reduced, which may be accompanied by an increased risk of depression. Thus, field 25 may be a kind of "master controller" of the neural circuitry of depression.

The processing of all emotional and cognitive information in the limbic system is of a biochemical nature: certain neurotransmitters are released (from Latin transmuto - I transmit; biological substances that determine the conduction of nerve impulses). If cognitive processes proceed against the background of positive emotions, then neurotransmitters such as gamma-aminobutyric acid, acetylcholine, interferon and interglukins are produced. They activate thinking and make memorization more efficient. If the learning processes are built on negative emotions, then adrenaline and cortisol are released, which reduce the ability to learn and remember.

Terms Development of the CNS in the prenatal period of ontogenesis Embryo stage 2-3 weeks Formation of the neural plate 3-4 weeks Neural tube closure 4 weeks Formation of three cerebral vesicles 5 weeks Formation of five cerebral vesicles 7 weeks Growth of the cerebral hemispheres, the beginning of neuroblast proliferation 2 months. Growth of the cerebral cortex with a smooth surface Fetal stages 2, 5 months. Thickening of the cerebral cortex 3 months. The beginning of the formation of the corpus callosum and the growth of glia 4 months. Growth of lobules and sulci in the cerebellum 5 months. Formation of the corpus callosum, growth of primary sulci and histological layers 6 months Differentiation of cortical layers, myelination. formation of synaptic connections, formation of interhemispheric asymmetry and intersexual differences 7 months. The appearance of six cell layers, furrows, convolutions, asymmetry of the hemispheres 8-9 months. The rapid development of secondary and tertiary sulci and convolutions, the development of asymmetry in the structure of the brain, especially in the temporal lobes

The first stage (from the prenatal period to 2-3 years) The basis (the first functional block of the brain) is laid for the interhemispheric provision of neurophysiological, neurohumoral, sensory-vegetative and neurochemical asymmetries. The first functional block of the brain provides the regulation of tone and wakefulness. The structures of the brain of the first block are located in the stem and subcortical formations, which simultaneously tone the cortex and experience its regulatory influence. The main brain formation that provides tone is the reticular (network) formation. The ascending and descending fibers of the reticular formation are a self-regulating formation of the brain. At this stage, for the first time, the deep neurobiological prerequisites for the formation of the future style of mental and educational activity of the child declare themselves.

Even in utero, the child himself determines the course of his development. If the brain is not ready for the moment of childbirth, then birth trauma is possible. The process of birth largely depends on the activity of the organism of the child. He must overcome the pressure of the birth canal of the mother, make a certain number of turns and repulsive movements, adapt to the action of gravitational forces, etc. The success of the birth depends on the sufficiency of the cerebral systems of the brain. For these reasons, there is a high probability of dysontogenetic development of children born by caesarean section, premature or postmature.

By the birth of a child, the brain is large relative to body weight and is: in a newborn - 1/8-1/9 per 1 kg of body weight, in a child of 1 year - 1/11-1/12, in a child of 5 years - 1/13- 1/14, in an adult - 1/40. The pace of development of the nervous system occurs faster, the smaller the child. It proceeds especially vigorously during the first 3 months of life. Differentiation of nerve cells is achieved by the age of 3, and by the age of 8, the cerebral cortex is similar in structure to the cerebral cortex of an adult.

The blood supply to the brain in children is better than in adults. This is due to the richness of the capillary network, which continues to develop after birth. Abundant blood supply to the brain provides the need for rapidly growing nerve tissue in oxygen. And its need for oxygen is more than 20 times higher than that of muscles. The outflow of blood from the brain in children of the first year of life differs from that in adults. This creates conditions conducive to a greater accumulation of toxic substances and metabolites in various diseases, which explains the more frequent occurrence of toxic forms of infectious diseases in young children. At the same time, the substance of the brain is very sensitive to increased intracranial pressure. An increase in CSF pressure causes a rapid increase in degenerative changes in nerve cells, and a longer existence of hypertension causes their atrophy and death. This is confirmed in children who suffer from intrauterine hydrocephalus.

The dura mater in newborns is relatively thin, fused with the bones of the base of the skull over a large area. The venous sinuses are thin-walled and relatively narrower than in adults. The soft and arachnoid membranes of the brain of newborns are exceptionally thin, the subdural and subarachnoid spaces are reduced. The cisterns located at the base of the brain, on the other hand, are relatively large. The cerebral aqueduct (Sylvian aqueduct) is wider than in adults. As the nervous system develops, the chemical composition of the brain also changes significantly. The amount of water decreases, the content of proteins, nucleic acids, lipoproteins increases. The ventricles of the brain. 1 - left lateral ventricle with frontal, occipital and temporal horns; 2 - interventricular opening; 3 - third ventricle; 4 - Sylvian plumbing; 5 - fourth ventricle, side pocket

The second stage (from 3 to 7-8 years). It is characterized by the activation of interhippocampal commissural (commissures - nerve fibers that interact between the hemispheres) systems. This area of ​​the brain provides the interhemispheric organization of memorization processes. Interhemispheric asymmetries are fixed at this segment of ontogenesis, the predominant function of the hemispheres is formed in terms of speech, individual lateral profile (combination of the dominant hemisphere and the leading arm, leg, eye, ear), and functional activity. Violation of the formation of this level of the brain can lead to pseudo-left-handedness.

The second functional block receives, processes and stores information. It is located in the outer sections of the new cerebral cortex and occupies its posterior sections, including the visual (occipital), auditory (temporal) and general sensitive (parietal) cortex zones. These areas of the brain receive visual, auditory, vestibular (general sensitive) and kinesthetic information. This also includes the central zones of gustatory and olfactory reception.

For the maturation of the functions of the left hemisphere, the normal course of ontogenesis of the right hemisphere is necessary. For example, it is known that phonemic hearing (semantic discrimination of speech sounds) is a function of the left hemisphere. But, before becoming a link of sound discrimination, it must be formed and automated as a tonal sound discrimination in the right hemisphere with the help of the child's all-round interaction with the outside world. Deficiency or unformedness of this link in the ontogeny of phonemic hearing can lead to delays in speech development.

The development of the limbic system allows the child to make social connections. Between the ages of 15 months and 4 years, primitive emotions are generated in the hypothalamus and amygdala: rage, fear, aggression. As the neural networks develop, connections are formed with the cortical (cortical) parts of the temporal lobes responsible for thinking, more complex emotions appear with a social component: anger, sadness, joy, grief. With the further development of nerve networks, connections with the anterior parts of the brain are formed and such subtle feelings as love, altruism, empathy, and happiness develop.

The third stage (from 7 to 12-15 years old) Interhemispheric interaction is developing. After the maturation of the hypothalamic-diencephalic structures of the brain (stem), the maturation of the right hemisphere begins, and then the left. The maturation of the corpus callosum, as already noted, is completed only by the age of 12-15. Normal maturation of the brain occurs from the bottom up, from the right hemisphere to the left, from the posterior parts of the brain to the anterior. Intensive growth of the frontal lobe begins no earlier than 8 years and ends by 12-15 years. In ontogeny, the frontal lobe is laid first, and ends its development last. The development of Broca's center in the frontal lobe makes it possible to process information through internal speech, which is much faster than with verbalization.

The specialization of the cerebral hemispheres in each child occurs at a different speed. On average, the figurative hemisphere experiences a jump in the growth of dendrites at 4-7 years, the logical hemisphere - at 9-12 years. The more actively both hemispheres and all lobes of the brain are used, the more dendritic connections are formed in the corpus callosum and myelinated. A fully formed corpus callosum transmits 4 billion signals per second through 200 million nerve fibers, mostly myelinated and connecting the two hemispheres. Integration and quick access to information stimulate the development of operational thinking and formal logic. In girls and women, there are more nerve fibers in the corpus callosum than in boys and men, which provides them with higher compensatory mechanisms.

Myelination in different areas of the cortex also proceeds unevenly: in primary fields it ends in the first half of life, in secondary and tertiary fields it continues up to 10-12 years. Flexing's classical studies showed that the myelination of the motor and sensory roots of the optic tract is completed in the first year after birth, the reticular formation - at 18 years old, and the associative pathways - at 25 years old. This means that those neural pathways that play the most important role in the early stages of ontogenesis are formed first. The process of myelination is closely correlated with the growth of cognitive and motor abilities in the preschool years.

By the time the child enters school (at the age of 7), his right hemisphere is developed, and the left hemisphere is updated only by the age of 9. In this regard, the education of younger schoolchildren should take place naturally for them in the right hemisphere way - through creativity, images, positive emotions, movement, space, rhythm, sensory sensations. Unfortunately, at school it is customary to sit still, not to move, to learn letters and numbers linearly, to read and write on a plane, that is, in the left hemisphere way. That is why training very soon turns into coaching and training a child, which inevitably leads to a decrease in motivation, stress and neuroses. At the age of 7, only “external” speech is well developed in a child, so he literally thinks out loud. He needs to read and think aloud until "inner" speech is developed. Translation of thoughts into written speech is an even more complex process when many areas of the neocortex are involved: sensitive, main auditory, the center of auditory associations, the main visual, motor area of ​​speech and the cognitive center. Integrated thought patterns are transmitted to the vocalization area and the basal ganglion of the limbic system, which makes it possible to build words in oral and written speech.

Age Stages of development of the brain region Functions From conception to 15 months Stem structures Basic survival needs - food, shelter, protection, safety. Sensory development of the vestibular apparatus, hearing, tactile sensations, smell, taste, vision 15 months - 4.5 g Limbish system Development of the emotional and speech sphere, imagination, memory, mastery of gross motor skills 4.5-7 years Right (figurative) hemisphere Processing in the brain of a holistic picture based on images, movement, rhythm, emotions, intuition, external speech, integrated thinking 7-9 years Left (logical) hemisphere Detailed and linear processing of information, improvement of speech, reading and writing, counting, drawing, dancing skills , perception of music, motor skills of hands 8 years Frontal lobe Improvement of fine motor skills, development of inner speech, control of social behavior. Development and coordination of eye movements: tracking and focusing 9-12 years old Corpus callosum and myelination Complex processing of information by the whole brain 12-16 years old Hormonal surge Formation of knowledge about oneself, one's body. Understanding the significance of life, the emergence of public interests 16-21 years A holistic system of intellect and body Planning the future, analyzing new ideas and opportunities 21 years and beyond Intensive leap in the development of the neural network of the frontal lobes , love, empathy) and fine motor skills

The cranial nerves include: 1. Olfactory nerves (I) 2. Optic nerve (II) 3. Oculomotor nerve (III) 4. Trochlear nerve (IV) 5. Trigeminal nerve (V) 6. Abducens nerve (VI) 7. Facial nerve (VII) 8. Vestibulocochlear nerve (VIII) 9. Glossopharyngeal nerve (IX) 10. Vagus nerve (X) 11. Accessory nerve (XI) 12. Hypoglossal nerve (XII) Each cranial nerve goes to a specific foramen at the base of the skull , through which it leaves its cavity.

Spinal cord (dorsal view): 1 - spinal ganglion; 2 - segments and spinal nerves of the cervical spinal cord; 3 - cervical thickening; 4 - segments and spinal nerves of the thoracic spinal cord; 5 - lumbar thickening; 6 - segments and spinal nerves of the lumbar; 7 - segments and spinal nerves of the sacral region; 8 - terminal thread; 9 - coccygeal nerve The cervical thickening corresponds to the exit of the spinal nerves heading to the upper limbs, the lumbar thickening corresponds to the exit of the nerves following to the lower limbs.

There are 31 segments in the spinal cord, each corresponding to one of the vertebrae. In the cervical region - 8 segments, in the thoracic region - 12, in the lumbar and sacral - 5 each, in the coccygeal region - 1. The area of ​​\u200b\u200bthe brain with two pairs of roots extending from it is called a segment.

Shells of the spinal cord (cervical): 1 - spinal cord, covered with a soft membrane; 2 - arachnoid shell; 3 - dura mater; 4 - venous plexus; 5 - vertebral artery; 6 - cervical vertebra; 7 - front spine; 8 - mixed spinal nerve; 9 - spinal node; 10 - posterior root The soft, or vascular, membrane contains ramifications of blood vessels, which then penetrate into the spinal cord. It has two layers: inner, fused with the spinal cord, and outer. The arachnoid is a thin connective tissue plate). Between the arachnoid and pia mater is the subarachnoid (lymphatic) space filled with cerebrospinal fluid. The dura mater is a long, spacious sac that surrounds the spinal cord.

The dura mater is connected to the arachnoid in the region of the intervertebral foramina on the spinal nodes, as well as at the attachment sites of the dentate ligament. The dentate ligament and the contents of the epidural, subdural, and lymphatic spaces protect the spinal cord from injury. Longitudinal grooves run along the surface of the spinal cord. These two grooves divide the spinal cord into right and left halves. On the sides of the spinal cord, two rows of anterior and posterior roots depart. The membranes of the spinal cord in a transverse section: 1 - dentate ligament; 2 - arachnoid shell; 3 - posterior subarachnoid septum; 4 - subarachnoid space between the arachnoid and soft shells; 5 - vertebra in cut; 6 - periosteum; 7 - dura mater; 8 - subdural space; 9 - epidural space

A transverse section of the spinal cord shows gray matter that lies inward from the white matter and resembles the shape of an H or a butterfly with outstretched wings. Gray matter runs the entire length of the spinal cord around the central canal. White matter makes up the conduction apparatus of the spinal cord. White matter connects the spinal cord with the overlying parts of the central nervous system. White matter lies on the periphery of the spinal cord. Scheme of a transverse section of the spinal cord: 1 - oval bundle of the posterior cord; 2 - back spine; 3 - Roland's substance; 4 - rear horn; 5 - front horn; 6 - front spine; 7 - tectospinal path; 8 - ventral corticospinal path; 9 - ventral vestibulospinal path; 10 - olivospinal path; 11 - ventral spinal tract; 12 - lateral vestibulospinal tract; 13 - spinothalamic tract and tectospinal tract; 14 - rubrospinal tract; 15 - lateral corticospinal path; 16 - dorsal spinocerebellar path; 17 - the path of Burdakh; 18 - Gaulle way

The spinal nerves are paired (31 pairs), metamerically located nerve trunks: 1. Cervical nerves (CI-CVII), 8 pairs 2. Thoracic nerves (Th. I-Th. XII), 12 pairs 3. Lumbar nerves (LI- LV), 5 pairs 4. Sacral nerves (SI-Sv), 5 pairs 5. Coccygeal nerve (Co. I-Co II), 1 pair, rarely two. The spinal nerve is mixed and is formed by the fusion of its two roots: the posterior root (sensory) and the anterior root (motor).

Basic functions of the spinal cord The first function is reflex. The spinal cord carries out motor reflexes of skeletal muscles independently. Examples of some motor reflexes of the spinal cord are: 1) elbow reflex - tapping on the tendon of the biceps muscle of the shoulder causes flexion in the elbow joint due to nerve impulses that are transmitted through 5-6 cervical segments; 2) knee reflex - tapping on the tendon of the quadriceps femoris muscle causes extension in the knee joint due to nerve impulses that are transmitted through the 2nd-4th lumbar segments. The spinal cord is involved in many complex coordinated movements - walking, running, labor and sports activities, etc. The spinal cord carries out vegetative reflexes of changes in the functions of internal organs - the cardiovascular, digestive, excretory and other systems. Thanks to reflexes from proprioreceptors in the spinal cord, motor and autonomic reflexes are coordinated. Through the spinal cord, reflexes are also carried out from internal organs to skeletal muscles, from internal organs to receptors and other organs of the skin, from an internal organ to another internal organ.

The second function: conductive is carried out due to the ascending and descending paths of the white matter. Along the ascending paths, excitation from the muscles and internal organs is transmitted to the brain, along the descending paths - from the brain to the organs.

The spinal cord is more developed than the brain at birth. Cervical and lumbar thickening of the spinal cord in newborns is not determined and begins to contour after 3 years of age. The rate of increase in the mass and size of the spinal cord is slower than that of the brain. Doubling the mass of the spinal cord occurs by 10 months, and tripling - by 3-5 years. The length of the spinal cord doubles by the age of 7-10, and it increases somewhat more slowly than the length of the spine, so the lower end of the spinal cord moves upward with age.

The structure of the autonomic nervous system Part of the peripheral nervous system is involved in the conduction of sensitive impulses and sends commands to the skeletal muscles - the somatic nervous system. Another group of neurons controls the activity of internal organs - the autonomic nervous system. The vegetative reflex arc consists of three links - sensitive, central and executive.

The structure of the autonomic nervous system The autonomic nervous system is divided into sympathetic, parasympathetic and metasympathetic divisions. The central part is formed by the bodies of neurons lying in the spinal cord and brain. These clusters of nerve cells are called autonomic nuclei (sympathetic and parasympathetic).

Topic: "Higher nervous activity"

• Tasks:
• 1. Describe unconditioned and conditioned reflexes.
• 2. Show that human GNI is based on the formation and inhibition of reflexes

• Pavlenko S.E

• Higher nervous activity- Another, most important, function of the nervous system.
• R. Descartes. The founder of the doctrine of higher nervous activity is I.M. Sechenov, in 1863 his book "Reflexes of the Brain" was published. Ivan Mikhailovich believed that all human mental activity is based on reflexes.
• Higher nervous activity- the activity of the higher parts of the central nervous system, which ensure the adaptability of animals and humans to environmental conditions.

• Creation of the doctrine of GNI. reflexes

• I.P. Pavlov experimentally confirmed the validity of the views of I.M. Sechenov and created the doctrine of conditioned and unconditioned reflexes.
• Unconditioned reflexes are characterized by:
• 1. These are congenital reflexes, inherited (swallowing, salivation, breathing);
• 2. They are specific, characteristic of all individuals of a given species;
• 3. Have permanent reflex arcs;
• 4. Relatively constant;
• 5. Carried out in response to a certain irritation;
• 6. Reflex arcs close in the spinal cord or subcortical nodes of the brain.

• Creation of the doctrine of GNI. reflexes

• An example of an unconditioned reflex is salivation in a dog with a salivary gland fistula. When food enters the oral cavity, the receptors of the tongue are excited, the processes of sensory neurons transmit the excitation to the medulla oblongata, where the salivary center is located, then the excitation is transmitted through the motor neurons to the salivary gland and salivation begins.

• Creation of the doctrine of GNI. reflexes

• Unconditioned reflexes include food, respiratory, defensive, sexual, orienting reflexes.
• Conditioned reflexes are characterized by:
• 1. Acquired by the body during life;
• 2. Individual, formed on the basis of personal life experience;
• 3. They do not have ready-made reflex arcs, arcs are formed under certain conditions;
• 4. Unstable, may disappear (slow down);
• 5. Formed on the basis of innate reflexes in response to any irritation;
• 6. Carried out due to the activity of the cerebral cortex.

• Creation of the doctrine of GNI. reflexes

• The formation of a conditioned reflex occurs when combined in time indifferent stimulus with unconditional.
• The indifferent stimulus must precede the unconditioned one. Then he becomes conditional.
• For the formation of a strong temporary connection, it is necessary to repeatedly reinforce the conditioned stimulus with an unconditioned one.

• Creation of the doctrine of GNI. reflexes

• The action of an indifferent stimulus leads to the appearance of excitation in one nerve center of the cortex, then excitation occurs in another nerve center under the action of an unconditioned stimulus, and a temporary connection arises between them.
• With repeated combinations, this connection becomes stronger, a conditioned reflex to a given stimulus is developed.
• An example is the secretion of saliva in response to the type of food, its smell, at the time of feeding, to any conditioned food stimulus.

• Inhibition of reflexes

• In the cerebral cortex, along with the processes of excitation, processes of inhibition also take place. There are two types of braking - external and internal.
• external braking. Occurs as a result of the action of a new stimulus. A new focus of excitation inhibits the existing focus. It is characteristic not only for the cortex, but also for the lower parts of the central nervous system, therefore the second name is unconditional inhibition. For example, extraneous noise inhibits salivation in a dog.

• Inhibition of reflexes

• Internal braking develops only in the cortex. Hence the second name conditional inhibition. An indispensable condition is the non-reinforcement of the conditioned stimulus by the unconditioned one. If the reflex to light developed in the dog is not reinforced with food, then the reflex weakens and disappears.
• In nature, unreinforced conditioned reflexes are inhibited and new ones are formed.. For example, the drying up of a reservoir from which animals drank will lead to the fact that they will stop coming to it and will find a new reservoir. There will be inhibition of some conditioned reflexes and the formation of new ones.

• Inhibition of reflexes

• Another type of internal inhibition - differentiation. If one stimulus is reinforced, and the one close to it is not reinforced, then a conditioned reflex reaction will occur only to the reinforced stimulus. For example, by the nature of the conditional knock on the door, you can determine who came - your own or others.
• A.A. Ukhtomsky developed the foundations of the doctrine of the dominant - the predominant system of interconnected centers that temporarily determine the nature of the body's response to external and internal stimuli. There are food, sexual, defensive and other types of dominants. Cats in heat have any sound ....

• GNI of humans and animals

• Higher nervous activity is inherent in both man and animals. In animals, the higher nervous activity depends on the complexity of the nervous system, the more complex it is, the less role play the instincts, the greater the role played by learning.
• For example, the offspring of the cross-spider appears in the spring, when the parents have already died, but young spiders are able to build a trapping web, their behavior is quite hard-coded.

• A certain sequence of unconditioned reflexes that determines some forms of behavior is called instinct. An example of instinctive activity is the construction of a trapping net by a cross-spider, a dam by beavers.

• GNI of humans and animals

• GNI of humans and animals

• Plays an important role in learning imprinting - imprinting. In animals, it manifests itself in the reaction of newborns following the first moving object. For example, K Lorenz and geese….
• In humans, it manifests itself at the age of 6 weeks to 6 months, is associated with the mother and the feeling of comfort and safety that occurs during feeding, hygiene care, communication between mother and child.

• GNI of humans and animals

• Human children raised by animals will never become full-fledged people due to lack of proper education.
• Unlike animals, the human cortex has a greater ability to perceive patterns in the surrounding world.

• GNI of humans and animals

• And the main difference between the higher nervous activity of people is associated with the presence of speech - the second signal system according to I.P. Pavlov.
• The first signaling system delivers information directly through the senses, the second signaling system is associated with the perception of words heard during pronunciation or visible during reading. With the development of the second signaling system, it became possible to store and transmit information to the next generations, a basis appeared for the development of abstract thinking, consciousness. “The word,” wrote I.P. Pavlov, “made us people.”
• Thinking . One of the main functions of the brain is associated with the work of associative zones, especially the frontal cortex. Allows you to choose the most optimal behavior in response to incoming information. The choice is based on personal experience or already available information, provides human reasoning activity .

• Protective adaptation of the body from overwork, protective inhibition of the cerebral cortex. During sleep, brain cells restore their efficiency. sleep center located in the midbrain, a mediator that causes the development of a sleepy state - serotonin. The destruction of the sleep center leads to a decrease in the amount of serotonin and the person loses the opportunity to fall asleep.

• Wakefulness depends on reticular formation medulla oblongata, pons and anterior nuclei of the hypothalamus, whose axons support the excitation of the cerebral cortex.
• EEG (electroencephalogram) shows that the sleep process is divided into several cycles, the duration of which is approximately 90 minutes. 70-80 minutes continues slow wave sleep, when the brain is more inhibited, rests.

• Slow and large electrical waves appear in the cerebral cortex. Then 10-15 minutes fast wave, paradoxical sleep, which is accompanied by involuntary movement of the eyes, fingers, mimic muscles, metabolism increases, pulse and breathing quicken. It is during these periods that a person sees dreams, small and fast electrical waves appear in the cortex.

• Within 6-8 hours of sleep, REM sleep phases appear 4-5 times, becoming longer and longer. In general, REM sleep takes up about 20% of the time.
• A person usually wakes up in REM sleep, the peptide that interrupts sleep is thyroid-stimulating hormone.
• Interesting facts: Napoleon and Edison slept 2 hours a day.

• Repetition

• Fill in the tables:

• Repetition

• What is the sequence of elements of the reflex arc of the unconditioned salivary reflex.
• What is the sequence of elements of the reflex arc of the conditioned salivary reflex.

• Repetition

• Correct judgments:
• An unconditioned stimulus is necessary for the formation of a conditioned reflex.
• Conditioned reflexes are associated with the formation of temporary connections between various centers in the cortex.
• For the formation of a conditioned reflex, it is necessary that an indifferent stimulus begin to act a few seconds earlier than the unconditioned one, after a few repetitions it becomes a conditioned stimulus.
• Conditioned reflexes are formed for life.
• Conditioned reflexes are inherited.
• The doctrine of conditioned reflexes was developed by I.M. Sechenov.
• The formation of conditioned reflexes is associated with the cerebral cortex.
• Unconditional (external) inhibition is associated with the extinction of the conditioned reflex without its reinforcement by the unconditioned one.

• Repetition

• Correct judgments:
• Internal inhibition allows you to adapt to the changed conditions of life.
• External inhibition allows you to adapt to sudden changes in the surrounding world.
• The students' reaction to the call from the lesson is an example of internal inhibition.

• Which of the Russian scientists first showed that human mental activity is based on reflexes?
• Which Russian scientist created the doctrine of conditioned reflexes?
• What reflexes are called unconditioned?
• What reflexes are called conditioned?
• What is instinct?
• Define higher nervous activity.
• Is higher nervous activity inherent in animals?
• Which arcs of reflexes exist from birth and persist throughout life?

• Repetition

• Give short answers to the questions:
• What arcs of reflexes are formed in the process of life and can fade away?
• What is the name of the nervous connection that occurs between different centers during the formation of a conditioned reflex?
• What conditions are necessary for the formation of a conditioned reflex?
• What two types of inhibition of reflexes do you know?
• In response to the car's horn, the pedestrian stopped. What kind of braking is this?
• The dog has developed a food reflex to the sound of a rattle. Subsequently, he ceased to be supported by food and slowed down. What kind of braking is this?
• What information does a person perceive with the help of the first signaling system?
• What information does a person perceive with the help of the second signaling system?

• Repetition

• Give short answers to the questions:
• What is a dominant?
• Who developed the doctrine of dominance?

• The main terms of the topic:
• unconditioned reflexes.
• Conditioned reflexes.
• Temporary connections.
• Unconditioned stimulus.
• Conditioned stimulus.
• Unconditional inhibition.
• Conditional inhibition.
• Dominant principle of A.A. Ukhtomsky.
• Second signal system.
• Imprinting.

The study of higher nervous activity in Russia is associated primarily with the names of two great scientists, two great scientists. The study of higher nervous activity in Russia is associated primarily with the names of two great scientists, two great scientists Ivan Petrovich Pavlov (). Ivan Mikhailovich Sechenov ()

The merit of I. M. Sechenov is that he proved that the brain can both enhance the reflexes of the spinal cord and inhibit them. It was the discovery of central inhibition that brought I. M. Sechenov fame and worldwide recognition. The merit of I. M. Sechenov is that he proved that the brain can both enhance the reflexes of the spinal cord and inhibit them. It was the discovery of central inhibition that brought I. M. Sechenov fame and worldwide recognition. He showed that the higher parts of the nervous system are able to regulate the work of the lower parts. This proved the multilevel organization of the brain. The higher the part of the brain is located, the more complex functions it performs.

IP Pavlov continued his research and found that all reflexes can be divided into two large groups. IP Pavlov associated the formation of conditioned reflexes with the work of the cerebral cortex. They arise under the obligatory condition of combining some irritation, even a minor one, with vital irritations (for example, food, pain, danger) and become their signals. Reflexes congenital (unconditioned) (conditioned) acquired

Types of instincts Vital (failure to satisfy the need leads to the death of the individual, implementation does not require the participation of another individual) Role or zoosocial (aimed at the survival of the species, the effective existence of the group - “what is good for the mind is good for you” Self-development instincts (facing the future, aimed at improvement of mental activity)

Conditioned reflexes Conditioned reflexes are individually acquired systemic adaptive reactions of animals and humans, arising on the basis of the formation in the central nervous system of a temporary connection between a conditioned (signal) stimulus and an unconditional reflex act

The main characteristics of the conditioned reflex (according to I.P. Pavlov) 1) Acquisition of conditioned reflexes (innateness of unconditioned reflexes) 2) Individuality of the conditioned reflex (specific nature of the unconditioned reflex) 3) Variability and the possibility of cancellation (inhibition) of the conditioned reflex 4) Signal character and principle leading reflection in a conditioned reflex

A bowl full of food was placed in front of the dog. The dog starts eating. The unconditioned reflex is activated. From the olfactory receptors of the dog, a signal enters the brain - from the subcortex to the cerebral cortex and back, and then to the salivary glands of the dog. Saliva begins to flow. 1 - Salivation center in the subcortex, 3 - Salivation center in the cerebral cortex, 4 - Salivary gland. 2.

The dog eats from a bowl. A light bulb is on in her field of vision while she is eating. From the visual receptors, information is transmitted to the visual center of the dog's brain about the light bulb being turned on. If the light bulb burns every time a dog eats dozens of times in a row, then a new connection is formed in his brain between the visual center and the center of salivation. So the dog will acquire a conditioned reflex that starts working when the light is turned on. 1 - Salivation center in the subcortex, 2 - Visual center in the cerebral cortex, 3 - Salivation center in the cerebral cortex, 4 - Salivary gland. 3.

Now when the light bulb is turned on, the dog will salivate, even if there is no bowl of food in front of him. A nerve impulse is transmitted from the eyes to the brain, which travels from the visual center to the salivation center of the cerebral cortex, then to the subcortex and from there to the salivary gland of the dog. 1 - Salivation center in the subcortex, 2 - Visual center in the cerebral cortex, 3 - Salivation center in the cerebral cortex, 4 - Salivary gland. 4.

Classification of conditioned reflexes By origin - natural and artificial By the nature of unconditioned reinforcement - food, defensive, sexual, research By the nature of the conditioned signal - light, sound, tactile, olfactory, temperature, etc. By the nature of the receptors - exteroceptive, interoceptive, proprioceptive By the ratio of stimuli in time - cash (coinciding, set aside), trace, late By degree of complexity - 1, 2, order

Conditions for the development of conditioned reflexes Condition of time - the preliminary or simultaneous action of the conditioned and unconditioned stimuli Condition of strength - the unconditioned stimulus must be stronger (more vital) than the conditioned Condition of indifference - the conditioned stimulus must be indifferent Condition of sensory limitation - the absence of extraneous stimuli Condition of brain activity - the active state of the central nervous system

Unconditional inhibition is a type of inhibition of conditioned reflexes that occurs immediately in response to the action of an extraneous stimulus, i.e. is an innate, unconditional form of inhibition. this type of inhibition of conditioned reflexes occurs immediately in response to the action of an extraneous stimulus, i.e. is an innate, unconditional form of inhibition. Conditioned inhibition occurs when the conditioned stimulus is no longer reinforced by the unconditioned stimulus. occurs when the conditioned stimulus is no longer reinforced by the unconditioned stimulus. It is called internal because it is formed in the structural components of the conditioned reflex. It is called internal because it is formed in the structural components of the conditioned reflex. Conditional braking requires a certain time to develop. Ivan Petrovich Pavlov

Higher nervous activity (HNA) - nervous processes that underlie human behavior and ensure adaptability to environmental conditions. The founder of the doctrine of GNI is I.M. Sechenov, in 1863 his book "Reflexes of the Brain" was published. Ivan Mikhailovich believed that all human mental activity is based on reflexes.

Conditioned reflexes are reactions acquired during life, with the help of which the body adapts to environmental influences. The indifferent stimulus must precede the unconditioned one. Then it becomes conditional. For the formation of a strong connection, it is necessary to repeatedly reinforce the conditioned stimulus with an unconditioned stimulus. FLASH

Conditioned and unconditioned reflexes Unconditioned Conditioned * Are congenital * Developed throughout life * Are specific, characteristic of all individuals of a given species * Individual, formed on the basis of personal life experience * Constant and do not fade during life * Fickle, can disappear (slow down)

Conditioned and unconditioned reflexes Unconditioned Conditioned * Carried out in response to a certain irritation * Formed on the basis of unconditioned reflexes * Reflex arcs are closed in the spinal cord or subcortical nodes of the brain * Carried out due to the activity of the cerebral cortex

Inhibition of reflexes In the cerebral cortex, along with the processes of excitation, processes of inhibition also take place. There are two types of braking external and internal. 1. External braking (unconditional). Occurs as a result of the action of a new stimulus. A new focus of excitation inhibits the existing focus. For example, extraneous noise inhibits salivation in a dog.

2. Internal inhibition develops only in the cortex. A) Conditioned - non-reinforcement of the conditioned stimulus by the unconditioned. For example: * If the dog's reflex to light is not reinforced with food, then the reflex weakens and disappears. * The drying up of the reservoir from which the animals drank will lead to the fact that they will stop coming to it, they will find a new reservoir.

B) Differentiation. If one stimulus is reinforced, and the one close to it is not reinforced, then a conditioned reflex reaction will occur only to the reinforced stimulus. For example, according to the nature of the conditional knock on the door, you can determine who came inside or outside.

A.A. Ukhtomsky developed the basics of the doctrine of the dominant: a single focus of excitation temporarily dominates in the brain, as a result, the fulfillment of one reflex that is vital at the moment is ensured. There are defensive, food, sexual and other types of dominants.

Insight (from the English. insight - insight, insight). Indicates a sudden insight into the essence of a problem situation. In experiments with great apes, when they were offered tasks that could only be solved indirectly, it was shown that after a series of unsuccessful trials, the monkeys stopped active actions and simply looked at the objects around, after which they could quickly come to the correct solution. So, the famous monkey Imo, instead of picking grains from the sand, threw their mixture into the water, after which he collected the grains from the surface.

The first signaling system delivers information directly through the senses, the second signaling system is associated with the perception of words heard during pronunciation or visible during reading. With the development of the second signaling system, it became possible to store and transmit information to the next generations, a basis appeared for the development of abstract thinking, consciousness. “Word, wrote I.P. Pavlov, made us human." The main difference between the higher nervous activity of people is associated with the presence of a second signal system in their speech.

Phases of sleep 1) Slow-wave sleep: * Lasts minutes * Muscle and vascular tone decreases * Breathing is even

2) REM sleep: * minutes * Accompanied by involuntary movement of the eyes, fingers * Increased heart rate and breathing. * In this phase, a person sees dreams, small and fast electrical waves appear in the cortex.

Insomnia (insomnia) - the inability to fall asleep or frequent awakenings in the middle of sleep. Reason: stress, neurosis, frequent change of time zones. Drowsiness (hypersomnia) is often attributed to a poor night's sleep. But there is a rare disease - lethargy (a person can oversleep for several years).

There is a version that Nikolai Gogol's lethargic dream was mistaken for his death. This conclusion was reached when, during the reburial, scratches were found on the inner lining of the coffin, pieces of the lining were under Gogol's nails and the position of the body was changed (“turned over in the coffin”). thirty