1. Conditioned and unconditioned regulation of human activity

2. Higher and lower activity of nervous system  The lower nervous activity is directed to regulation of body functions and organ systems, unification them to entire organism. The lower nervous activity is performed due to congenital forms of behavior. The congenital forms are unconditioned reflexes, instincts; biological motivations and emotions.  At the adult person the lower nervous activity usually is not arises separately from other forms of behavior. Life training and purchase of acquiring experience results in specification and modification of congenital forms of behavior due to the conditioned-reflex mechanism.

3. Notion about conditioned reflexes  Conditioned reflexes are individually acquired system of adaptive reactions of the person and animals. It arises on the basis of formation in the central nervous system of temporary communication between centres, some of which percept new irritant and other control some unconditioned reflex. Thus, new irritant form an environment becomes conditional irritant. It warns person about approach of the subsequent kinds of activity and prepares him for future kinds of activity (eating, avoidance of danger and another).  With the help of the conditioned-reflex mechanism such function of nervous system as purposeful behavior of the person in an environment and society, the adaptation to varied conditions of an environment are carried out. Such activity of nervous system concerns to the higher nervous activity.

4. The mechanism of formation of conditioned reflexes  The structural basis of the higher nervous activity is brain cortex and the nearest subcortical centres. At formation of behavior in the central nervous system on some time are formed neuronal circuits of a different degree of complexity. In the environment all the time new irritants occur. Therefore in a brain cortex at each moment of time new combinations of neurons are activated.  Thus, in the brain cortex and the subcortical centres there is a mosaic and dynamics of excitation and braking, due to performance of the higher nervous activity. Such interactions between neurons give basis of thinking, emotions and behavior of the person.

6. Characteristic of conditional irritants  For development of a conditioned reflex it is necessary, that any factor of an environment, which may be perceived by one of analyzer systems of an organism, occur repeatedly and acted on an organism of the person or an animal. If at each occurrence this irritant outstrips a little or takes place simultaneously with performance of any unconditioned reflex in an organism, probability of development of a conditioned reflex very high. But for formation of a conditioned reflex still it is necessary, that the brain cortex be in an active, awake condition.  For development of a conditioned reflex the important value has optimum force of irritant, which may become conditional irritant. Small force irritant does not cause a sufficient level of activity in neurons of appropriate analyzer system. In this case the conditioned reflex is formed slowly. Such conditioned reflex exists the short period of time and then is fast inhibited.  In real conditions irritants from the environment do not occur as isolated factor. There are a set of similar irritants and such irritants, which operate simultaneously

8. Nervous processes, which lays in the base of conditioned reflexes formation  The opportunity spreading excitation in the central nervous system is caused by presence in it of numerous branches of shoots of nervous cells - axons and dendrites. Shoots connect neurons and the nervous centres in a uniform network. Strengthening of irritation neurons stimulates distribution of excitation on nervous circuits. Due to existence of such communications excitation long time may circulate on closed neuronal to circuits, till opportunities of synapses to transfer impulses will be exhausted or there will be a braking process in any of neurons, so the circuit will be opened.  The centre of excitation, which arises in a brain cortex under action of conditional stimulus may be spread on neuronal circuits in all directions. But if simultaneously in an organism the unconditioned reflex is carried out, in a zone of cortical representations of this reflex the prepotent centre varying a direction spreading of excitation develops. In such a case distribution of the excitation caused by a conditional irritant, will be directed aside dominants.

9. Peculiarities of dominanta Dominanta (from Latin dominare - to dominate) - is the centres of excitation prevailing in the central nervous system, which change and subordinate to themselves activity of other nervous centres at present. The principle of a dominant is one of main principles of activity of the central nervous system. The Russian scientist O.O. Ukhtomsky was formulated these principles. Dominanta (from Latin dominare - to dominate) - is the centres of excitation prevailing in the central nervous system, which change and subordinate to themselves activity of other nervous centres at present. The principle of a dominant is one of main principles of activity of the central nervous system. The Russian scientist O.O. Ukhtomsky was formulated these principles.  The prepotent centre of excitation is characterized by such properties:  1) Increase of excitability;  2) Stability of excitation;  3) Ability to summarize excitation - to accumulation of excitation from stranger irritants;  4) Ability to inhibit function of other nervous centres and reflex reactions;  5) Ability long time to keep excitation after the termination (ending) of irritation, which has caused it (inertia of a dominant).

11. Synaptic and membrane hypothesis of conditioned reflexes formation  It agrees when giving experimental researches, two neuron classes take part in formation of conditioned reflexes: command neurons which realize specific behavioral acts and modulating neurons, which adjust a condition of command neurons. Before the first appearance of stimulus and supporting reflex neurons were mainly monotouch. In process of the further development of a conditioned reflex neurons get ability to answer different stimulus, that is become polytouch. After the conditioned reflex is produced, again it is observed selective reaction of neurons - they answer only stimulus, which became conditional irritant.  The synaptic hypothesis considers that the mechanism of formation of a conditioned reflex is caused by change of an overall performance of synapses.  The membrane hypothesis asserts that in a basis of the mechanism of formation of a conditioned reflex change of excitability of postsyneptic membrane lays.

12. Classification of conditioned reflexes  I. On a way of formation:  1. Classical conditioned reflexes - are formed in natural conditions.  2. Tool conditioned reflexes - are developed artificially. More often they represent purposeful motor reactions. As supporting stimulus for their development the unconditioned reflex causing in a laboratory animal feeling of pleasure (effect of "award") or painful irritant, causing avoidance reaction usually serves.  II. Under the relation of conditional irritant to unconditional:  1. Natural conditioned reflexes - conditional irritant it is related to an unconditioned reflex. For example, a smell and how a food looks have the direct relation to irritation by food of tongue receptors, which starts unconditional salivatory discharge reaction.  2. Artificial conditioned reflexes - conditional irritant has no the direct relation to an unconditioned reflex which serves as a reinforcement. For example, the bell or a light signal in natural conditions have no the relation to unconditional salivatory discharge reflex.

13. Classification of conditioned reflexes (next)  III. On biological importance:  1. Food conditioned reflexes - provide getting food and digestion.  2. Sexual conditioned reflexes - provide sexual behavior.  3. Protective conditioned reflexes - provide defensive reactions.  4. Statokinetic conditioned reflexes - provide motor behavioral reactions and impellent skills.  5. Homeostatic conditioned reflexes - are directed on maintenance of a constancy of the inner environment of an organism.  III. On a degree of complexity:  1. Conditioned reflexes of the first order - the conditioned reflex is developed on the basis of a unconditioned reflex.  2. Conditioned reflexes of the second order - the conditioned reflex is developed on the basis of other conditioned reflex of the first order.  3. Conditioned reflexes of the third order - the conditioned reflex is developed on the basis of a conditioned reflex of the second order.  4. Conditioned reflexes of the higher order - are formed only at the high organization of nervous system. In human formation of conditioned reflexes of the second - twentieth order is probably.

15. Process of inhibition in the central nervous system  Formation of conditioned reflexes is not possible without process of inhibition in the central nervous system.  Braking of spreading impulses is provided with various mechanisms and results thus in various effects. I.P.Pavlov classified braking processes in the brain cortex as two groups: external (unconditional) and internal (conditional).

17. External (unconditional) inhibition  The rough reflex causes unconditional braking because it protects an organism from new unknown influences of an environment, which possibly may cause damaging or to warn of danger. At repeated occurrence of new irritant, which was no dangerous, its braking effect decreases. Such brake irritants refer to as time or dying away. There are also constant brake irritants, which keep brake effect long time. Pathological processes (for example inflammatory processes) or strong irritation of proprioreceptors (for example, overflow of a urine bladder, a rectum) often have such a value.  One more kind of external braking is security braking. It arises at action of very strong irritants or very long influence of usual force irritants.

20. Internal (conditional) braking  This is specific process, which is characteristic for cerebral cortex. It demands special conditions and training. The basic condition of development of internal braking is absence of unconditional reinforcement after action of conditional irritant when the reflex is already produced and functions.  Regular repeated action of conditional irritant without a reinforcement of it by unconditioned reflex results in gradual easing a conditioned reflex, and so to its disappearance, fading away. Such kind of braking refers as fading away.  Thanking to fading away braiking the brain is released from the information which under the present conditions has lost the value.

22. Differential braking  Differential braking develops, if one of two conditional irritants is always supported with an unconditioned reflex, and another - is not. In this case the conditioned reflex on supported irritant is kept. Another conditional irritant, which is not supported, every time causes a conditioned reflex worse while it will not disappear absolutely.  Differential braking allows specialization of conditioned reflex and is a basis of the adequate analysis of subjects and the phenomena of an environment, and also changes in the inner environment of an organism.

24. Conditional brake of existing reflex  One of versions of differential braking - a conditional brake. If to add new irritant to conditional irritant and to repeat this combination many times without any reinforcement, new irritant brake conditioned reflex produced earlier. In this case conditional irritant loses the alarm action, and inhibition of conditioned reflex occurs.  Conditional brake permits constantly specify character of conditional reflex reactions for concrete irritants from an environment.

26. Late braking  When the time interval between action of conditional and unconditional irritant is increased, the conditioned reflex appears with delay. In performance of a late reflex distinguish two phases - inactive, when reactions on conditional irritant is not present, and active, when there is a reflex reaction. Late braking helps to regulate work of internal visceral organs (for example, regulation secretion of the stomach after meal), develop skill to wait and to keep energy in case of strong irritation.  Braking in brain cortex is carried out by braking neurons. Most likely, this function is performed by star cells. It is established, that on the mechanism of braking in a brain cortex is caused by postsynaptic hyperpolarizing. It is caused basically by change of permeability of Cl- channels of postsynaptic membrane. The basic neurotransmitter in braking neurons is gamma- aminobatteric acid.

28. Stages of coditioned reflex activity  Stage of generalization of a conditioned reflex  Stage of specialization of a conditioned reflex  Inhibition of the conditioned reflex

29. Age peculiarities of inhibition  Braking of conditioned reflexes is possible since the first days of life of the child, basically with the help of external braking. At children of the first year of life both external and internal braking easily arises. Long action of irritant can brakes even rough reaction. Immaturity of the brain cortex neurons in newborn children causes fast development of braking process.  Conditional braking in the first years of life of the child is advanced very poorly. The force of all kinds of internal braking and speed of braking of conditioned reflexes increased with age. Children till 4 years of life distinguish irritants according to one attribute - color or shape usually. Integrative functions of the brain develop quickly. 5-6 year children already differentiate irritants according to 2-4 attributes. Ability to allocate the basic essential component among set of irritants develops later - by 10-17 years. In old age internal braking is disturbed, that decreases workability of a person.  Ability to security braking raises with aging, the excitation and braking ratio in the central nervous system is broken.

30. Coordination of functions in a brain cortex  All kinds of activity of the person are based on coordination of functions in a brain cortex due to processes of excitation and braking. In a healthy organism processes of excitation and braking in the central nervous system are in dynamic balance.  Processes of excitation and braking in the central nervous system are in complex cooperation and influence to each other. I.P.Pavlov has established such laws of excitation and braking interaction. Excitation arising in any centre inhibits other centres. Concentration promotes processes of differentiation and an induction. Around of the centre of excitation there are centres of braking, and around of the centres of braking - the centres of excitation. I.P.Pavlov has named it as cortical mosaic. But cells of the brain all time pass from exciting condition in braking and on the contrary. This phenomenon is named dynamics of excitation and braking in a brain cortex.

31. Cycle of dream and wakefulness  Processes of excitation and braking in the central nervous system, as well as other functions of an organism have daily cycle. The cycle of dream and wakefulness is one of vital needs of the organism. The basic function of dream is restoration of physical and mental forces, which allows maximal adaptation to change of conditions of the external and internal environment.  Dream is alternation of different functional conditions of the brain. During dream brain activity is reconstructed. There is a consolidation and processing of the information, which has arrived during wakefulness. In dreaming information moves from the short-term memory in the long-term. Activity of neurons in different departments of the brain cortex and subcortical nerve centres during dream remains practically same as well as during wakefulness.

32. Physiological characteristic of dream  According to modern representations, dream consists of two qualitatively various conditions - slow and fast dream. Slow dream is divided on some stages, according to changes on electroencephalogram.  The first stage is characterized by oppression of the basic alpha-rhythm, which is gradually replaced with low amplitude waves of different frequency.  The second stage is characterized by periodic occurrence of dream spindles.  The third and fourth stage is characterized by gradual increase on electroencephalogram of high amplitude slow deltas-waves. These stages correspond to deep dream.

33. Nerve substrate of dream  Numerous brain structures, which take part in the organization of dream, are located in the brain stem and were joined in somnolence system. Nucleus in the brain partition, in hypothalamus, serotoninaergic neurons in nucleus of a seam and thalamic synchronizing system concern to these structures.  Formation of fast dream connects with reticular nucleus of the midbrain and limbic structures of the brain.  Reticular inhibitory area is located medially and ventrally in the medulla. This area can inhibit the reticular facilitory area of the upper brain stem and thereby decrease activity in the superior portions in the b5rain as well. One of the mechanisms for this is to excite serotoninergic neurons ar crucial points in the brain.

34. Factors that cause dream There are four groups of factors which cause dream:  1) endogenous factors caused by exhaustion and somnolence substances;  2) endogenous cyclic processes in an organism;  3) unconditional reflex irritants as darkness, rest, position of a body, touch monotony, influence of temperature, atmospheric pressure;  4) conditioned reflexes to the certain conditions of dream, time of day, its duration.