Localization of speech functions in the cerebral cortex. Modern ideas about the localization of the function in the cerebral cortex
brain.
2. Motor functions.
3. Functions of the skin and propriocepital
sensitivity.
4. Hearing functions.
5. Summary functions.
6. Morphological foundations localization of functions in
cerebral core.
Motor analyzer core
The kernel of the auditory analyzer
Core of the visual analyzer
The core of the taste analyzer
Core of the skin analyzer
7. Bioelectric brain activity.
8. Literature.
The value of various sections of large bark
Hemispheres of the brain
From a long time, between scientists there is a dispute about the location (localization) of the sections of the cerebral cortex associated with various functions of the body. A wide variety of and mutually opposite points of view were expressed. Some believed that each function of our body corresponds to a strictly defined point in the cerebral cortex, others denied the presence of any centers; They attributed any reaction to the whole crust, considering it entirely unequivocal in functionality. The method of conditional reflexes was given the opportunity to I. P. Pavlov to find out a number of obscure issues and develop a modern point of view.
There are no strictly fractional localization of the cities in the cerebral cortex. This follows from experiments on animals, when after the destruction of certain sections of the bark, for example, the motor analyzer, after a few days the neighboring sites take on the function of the destroyed section and the movement of the animal are restored.
This ability of the cortical cells to replace the function of the precipitated areas is associated with a large plasticity of the cerebral cortex.
. P. Pavlov believed that individual bark areas have different functional importance. However, there are no strictly defined boundaries between these areas. Cells of one region are moving to neighboring areas.Figure 1. Communication scheme of bark departments with receptors.
1 - spinal or oblong brain; 2 - intermediate brain; 3 - brain bark
In the center of these areas there are clusters of the most specialized cells, the so-called analyzer cores, and on the periphery-less specialized cells.
In the regulation of the functions of the body, there are no strictly outlined some points, but many nervous elements of the crust.
Analysis and synthesis of incoming impulses and the formation of a response to them is carried out significantly large areas of the crust.
Consider some areas having mainly this or that value. The schematic location of the location of these areas is shown in Figure 1.
Motor functions. The cortical department of the motor analyzer is mainly in the anterior central ispuncture, the Kepende from the central (Roland) groove. In this area there are nervous cells, with the activities of which all the movements of the body are associated.
The processes of large nerve cells located in deep layers of the cortex are descended into the oblongable brain, where the significant part of them is crossed, that is, it turns on the opposite direction. After the transition, they are lowered along the spinal cord, where the rest is crossed. In the front horns of the spinal cord, they come into contact with self-engined nerve cells. Thus, the excitation that occurred in the crust comes to the motor neurons of the front horns of the spinal cord and then on their fibers goes to the muscles. Due to the fact that in oblong, and in part and in the spinal cord, the transition (crossroads) of motorways on the opposite direction, the excitation that occurred in the left hemisphere of the brain goes into the right half of the body, and pulses from the right hemisphere come to the left half of the body. That is why hemorrhage, wound or any other defeat of one side of the large hemispheres entails a violation of muscle activity of the opposite half of the body. Figure 2. Scheme of individual areas of the cortex of large hemispheres of the brain.
1 - Motor region;
2 - area of \u200b\u200bskin
and propriorasective sensitivity;
3 - visual region;
4 - hearing area;
5 - flavoring area;
6 - olfactory area
In the anterior central gyrus, the centers innervating different muscle groups are located in such a way that at the top of the motor area there are centers of lower limb movements, then below the center of the muscles of the body, even below the center of the front limbs and, finally, below all centers of the head muscles.
Centers of different muscle groups are presented unequal and occupy uneven areas.
Functions of skin and proprioceptive sensitivity. The area of \u200b\u200bthe skin and propriceceptive sensitivity in humans is predominantly behind the central (Roland) groove in the rear central urinet.
The localization of this area in humans can be installed by the method of electrical irritation of the cortex of the brain during operations. Irritation of various sections of the bark and the simultaneous survey of the patient about the sensations that it experiences, make it possible to make a fairly clear idea of \u200b\u200bthe specified area. With the same area associated with the so-called muscular feeling. The pulses arising in the propriate receptors in the joints, muscle tendons, are predominantly in this bark department.
The right hemisphere perceives impulses going on centripetal fibers mainly with the left, and the left hemisphere is predominantly with the right half of the body. This explains the fact that the defeat, for example, the right hemisphere will cause a sensitivity disturbance predominantly.
Hearing functions. The auditory area is located in the temporal share of the bark. When removing the temporal fractions, complex sound perception is disturbed, since the possibility of the analysis and synthesis of sound perceptions is disturbed.
Summary functions. The auditorium is in the occipital share of the cerebral cortex. When removing the occipital fraction of the brain, the dog comes a loss of vision. The animal does not see, stumps on items. Only pupil reflexes in humans are preserved. A violation of the visual region of one of the hemispheres causes half the vision of each eye. If the defeat touched the visual region of the left hemisphere, then the functions of the nasal part of the retina of one eye and the temporal part of the retina of another eye drop out.
Such a feature of lesion of vision is connected with the fact that the visual nerves along the way to the cortex are partially crossed.
The morphological foundations of the dynamic localization of functions in the core of the hemispheres of a large brain (centers of the cerebral cortex).
Knowledge of the localization of functions in the cerebral cortex has a huge theoretical value, as it gives an idea of \u200b\u200bthe nervous regulation of all the processes of the organism and to adapt it to the environment. It has great practical importance for the diagnosis of lesion places in the hemispheres of the brain.
The idea of \u200b\u200bthe localization of functions in the cerebral cortex is primarily connected with the concept of the cortical center. Back in 1874, Kievan Anata V. A, Betz spoke with the statement that each participation in the bark differs in the structure from other parts of the brain. This was the beginning of the teaching on the dormitory of the cerebral cortex - cytoarchitectonics (cytos - cell, architectones - build). Currently, it was possible to identify more than 50 different sections of the crust of cortical cytoarchitectonic fields, each of which differs from others in the structure and location of nerve elements. Of these fields, indicated by the rooms, a special map of human brain bark is composed.
o I.P. Pavlov, the center is the brain end of the so-called analyzer. Analyzer is a nervous mechanism that is the function of which is to decompose the well-known complexity of the external and inner world into separate elements, i.e. produce analysis. At the same time, thanks to wide connections with other analyzers, the synthesis of analyzers with each other and with different activities of the body occurs here. Figure 3. Map of cytoarchitoneic fields of the human brain (according to the Institute of MEGEA AMN USSR) at the top - the upper-tapeth surface, lower-medial surface. Explanation in the text.
Currently, the entire brain crust is considered as a solid perceiving surface. The bark is a set of circular ends of analyzers. From this point of view, we will consider the topography of the cortical departments of analyzers, i.e., the main perceive sections of the cortex of a large brain.
First of all, consider the tapered ends of the analyzers that perceive irritations from the inner environment of the body.
1. The kernel of the motor analyzer, that is, the analyzer of proprioceptive (kinesthetic) irritation emanating from bones, joints, skeletal muscles and their tendons, is in precentral urinet (fields 4 and 6) and LOBULUS PARACENTRALIS. Motor conventional reflexes are closed here. Motorial paralysis arising from the damage to the motor zone, I. P. Pavlov explains not damage to the motorcycle effectant neurons, and the violation of the kernel of the motor analyzer, as a result of which the bark does not perceive the kinesthetic irritations and movements become impossible. Motor analyzer kernel cells are laid in the middle layers of the motor zone cortex. In the deep layers (V, partly VI) there are gigantic pyramidal cells, which are of efferent neurons that I. P. Pavlov examines both insert neurons connecting the bark of the brain with subcortical nuclei, cerpent nerve cores and the front horns of the spinal cord, that is . with motor neurons. In a prechangeful winding, the human body, as well as in the rear, is properly head. At the same time, the right motor area is associated with the left half of the body and, on the contrary, for the pyramidal paths starting from it are crossed by part in the oblong, and part of the spinal cord. Muscles of the body, larynx, pharynges are under the influence of both hemispheres. In addition to pre-centered winding, propriceceptive impulses (muscular-articular sensitivity) come to the cera of post-central overhang.
2. The kernel of the motor analyzer, which is related to the combined rotation of the head and eyes in the opposite direction, is placed in the middle frontal winding, in the premotor region (field 8). This turn occurs during irritation of the field 17, located in the occipital share in the neighborhood with the core of the visual analyzer. Since when cutting the muscles of the eye in the bark of the brain (Motor Analyzer, Field 8), not only pulses from the receptors of these muscles are always received, but also impulses from the eet-cart (visual analyzer, field 77), then various visual irritations are always combined with different positions Eye, installed abbreviation of the muscles of the eyeball.
3. The kernel of the motor analyzer, through which the synthesis of targeted complex professional, labor and sports movements occurs, is placed in the left (in the right-hander) of the lower dark slicing, in Gyrus Supramarginalis (deep layers of field 40). These coordinated movements, formed on the principle of temporary ties and developed by the practice of individual life, are carried out through the connection of Gyrus Supramarginalis with a precentral winding. Under the defeat of the field 40, the ability to move in general, but the inability to make targeted movements, act - apraxia (PRACSIA - action, practice) appears.
4. The core of the analyzer of the position and movement of the head is a static analyzer (vestibular apparatus) in the brain core is definitely not yet localized. There is reason to assume that the vestibular apparatus is projected in the same area of \u200b\u200bthe crust as the snail, i.e. in the temporal share. Thus, during the defeat of fields 21 and 20 lying in the region of the middle and lower temporals, an ataxia is observed, that is an equilibrium disorder, shaking the body when standing. This analyzer, which plays a decisive role in a person's straightening, is of particular importance for the operation of pilots in the conditions of reactive aviation, since the sensitivity of the vestibular apparatus by the plane is significantly reduced.
5. The core of the pulse analyzer coming from the internally and vessels is located in the lower departments of the front and rear central convolutions. The centripetal impulses from the internships, vessels, involuntary muscles and the skin glands go to this bark department, from where the centrifugal paths are departed to subcortex vegetative centers.
In the premotor region (fields 6 and 8) there is a merge of vegetative functions.
Nervous impulses from the external environment of the body enter the cortical ends of the analyzers of the outside world.
1. The kernel of the auditory analyzer lies in the middle part of the upper temporal winding, on the surface facing an island, - fields 41, 42, 52, where the snail is projected. Damage leads to deafness.
2. The core of the visual analyzer is in the occipital share - fields 18, 19. On the inner surface of the occipital share, along the edges of Sulcus Icarmus, the visual path ends in the field 77. The retina's retina is designed here. With the damage to the core of the visual analyzer comes blindness. Above the field 17 is located in the field 18, with the defeat of which the vision is saved and the visual memory is lost. Even above, there is a field with a defeat of which the orientation in the unusual shelf is lost.
3. The core of the taste analyzer, according to the same data, is located in the lower post central urina, close to the centers of the muscles of the mouth and language, in others - in the nearest neighborhood with the cortical end of the olfactory analyzer, which explains the close relationship of the olfactory and taste. It has been established that the disorder of taste occurs when the field is damaged 43.
Analyzers of smelling, taste and hearing of each hemisphere are associated with receptors of the relevant bodies of both sides of the body.
4. The core of the skin analyzer (tactile, pain and temperature sensitivity) is located in a post-central urinet (fields 7, 2, 3) and in the top of the parietal area (fields 5 and 7).
Private skin view - recognition of items to the touch - stereogeneration (stereos - spatial, gnosis - knowledge) is associated with the section of the cortex of the upper dark slices (field 7) Cross: the left hemisphere corresponds to the right hand, right-handed hand. With damage to the surface layers of the field 7, the ability to recognize the items to the touch, with closed eyes.
Bioelectric brain activity.
The discharge of brain biopotentials - electroencephalography-gives an idea of \u200b\u200bthe level of physiological activity of the brain. In addition to the method of electroencephalography, the recording of bioelectric potentials, use the method of encephaloscopy-registration of vibrations of the brightness of the glow of a plurality of brain points (from 50 to 200).
The electroencephalogram is an integrative space-time indicator of spontaneous electrical activity of the brain. It distinguishes the amplitude (scope) of oscillations in microvolts and the frequency of oscillations in Hertz. In accordance with this, four types of waves differ in the electroencephalogram: -, -, - and -th. For -growth characteristic frequencies in the range of 8-15 Hz, with an amplitude of oscillations of 50-100 μV. It is recorded only in humans and higher monkeys in a state of wakefulness, with closed eyes and in the absence of external stimuli. Spectator stimuli inhibit -tem.
In individuals who have lively visual imagination, it may not be absent in general.
For the active brain, it is characteristic ( -tem. These are electrical waves with an amplitude of 5 to 30 μV and a frequency of 15 to 100 Hz, it is well recorded in the frontal and central regions of the brain. During sleep, it appears -tem. It is also observed with negative Emotions, painful states. The frequency of potentials -Rema from 4 to 8 Hz, amplitude from 100 to 150 μV during sleep appears and -tem - slow (with a frequency of 0.5-3.5 Hz), high amplitude (up to 300 μV ) fluctuations in the electrical activity of the brain.
In addition to the considered types of electrical activity, a person registers an e-wave (wave of an irritant) and spindle-shaped rhythms. Wave waiting is registered when performing conscious, expected actions. It precedes the appearance of an expected stimulus in all cases, even with a repeated repetition. Apparently, it can be considered as the electroencephalographic correlation of the action acceptor, which ensures the prediction of the results of the action before it is completed. Subjective readiness to respond to the action of the incentive strictly in a certain way is achieved by the psychological installation (D. N. Finds). The spindle-shaped rhythms of non-permanent amplitude, with a frequency of 14 to 22 Hz, appear during sleep. Various forms of activity of activity lead to a significant change in the rhythms of the bioelectric activity of the brain.
With mental work, it is enhanced by -temm, it disappears -at this. With muscle work of a static character, the desynchronization of the electrical activity of the brain is observed. Fast fluctuations with low amplitudes appear. The time of dynamic operation of PE- The riot of desynchronized and synchronized activity is observed accordingly at the moments of robust and recreation.
The formation of the conditional reflex is accompanied by the desynchronization of the wave activity of the brain.
Desynchronization of waves occurs when moving from sleep to wakefulness. In this case, the spindle-shaped sleep rhythms are replaced.
-Remom, the electrical activity of the reticular formation increases. Synchronization (the same in phase and the direction of the wave)
characteristic for the brake process. It is most distinctly expressed when it is turned off the reticular formation of the stem portion of the brain. The waves of the electroencephalogram, according to the majority of researchers, are the result of the summation of brake and exciting postsynaptic potentials. The electrical activity of the brain is not a simple reflection of metabolic processes in the nervous tissue. It is established, in particular, that in the impulse activity of individual accumulations of nerve cells, signs of acoustic and semantic codes are found.
Literature.
1. M.G.Prieves, N.K.Lystenkov, V.I. Bushkovich. "Anatomy
man. "
2. N.A. Fomin "Human Fisoology"
3. A.A. Markosyan Physiology.
Ministry of Higher and Vocational Education
Localization of functions in a large brain core
General characteristics.In certain areas of the large brain cortex, predominantly neurons are concentrated, perceiving one kind of stimulus: the occipital region is light, the temporal share is the sound, etc. However, after the removal of classical projection zones (hearing, visual), conditional reflexes are partially saved to the corresponding stimuli. According to the theory of I. P. Pavlov in a large brain core, there is a "core" of the analyzer (cortical end) and "scattered" neurons throughout the crust. Modern concept Localization of functions is based on the principle of multifunctionality (but not equivalent) of the cortical fields. The property of multifunctionality allows one or another cortical structure to be included in the provision of various forms of activity, implementing the main one, genetically inherent in it, the function (O.S. Adrianov). The degree of multifunctionality of various cortical structures of non-etinakov. In the fields of associative crust, it is higher. At the heart of multifunctionality, the multichannel of admission to the bark of the brain of afferent excitation, overlapping of afferent excitations, especially on the thalamic and cortical levels, which modulates the influence of various structures, for example, nonspecific thalamus nuclei, basal ganglia on cortical functions, the interaction of cortical-subcortical and intercussion tract of excitation. Using microelectrode technology, it was possible to register in various fields of large brain cortex activity of specific neurons that respond to incentives only one type of stimulus (only on light, only on sound, etc.), i.e. there is a multiple representation of functions in a large brain core .
Currently, a division of the bark on sensory, motor and associative (non-specific) zones (regions) is taken.
Sensory bark zones.Sensory information enters the projection boron, the cortical departments of analyzers (I.P. Pavlov). These zones are located mainly in dark, temporal and occipital shares. The rising paths in the touch bark come mainly from the relay sensory nuclei of the Talamus.
Primary sensory zones - These are the zones of the sensory cortex, irritation or destruction of which causes clear and constant changes in the sensitivity of the body (the kernel of analyzers according to I. P. Pavlov). They consist of monomodal neurons and form sensations of one quality. In primary sensory zones, there is usually a clear spatial (topographic) representation of parts of the body, their receptor fields.
The primary projection zones of the cortex consist mainly from the neurons of the 4th afferent layer for which a clear topical organization is characteristic. A significant part of these neurons has the highest specificity. For example, neurons of visual regions selectively react to certain signs of visual stimuli: Some - on the shades of color, others - to the direction of movement, the third - on the character of the lines (edge, strip, slope of the line), etc. However, it should be noted that the multimodal type neurons react to several types of irritants are also included in the primary zones of individual crust areas. In addition, there are neurons there, the reaction of which reflects the impact of non-specific (limbico-reticular, or modulating) systems.
Secondary sensory zones located around primary sensory zones, less localized, their neurons respond to several stimuli, i.e. They are polymodal.
Localization of sensory zones. The most important sensory area is dark Sharepost-central winding and the corresponding part of the paraccentral lobby on the medial surface of the hemispheres. This zone is indicated as somatosensory regionI.. Here there is a projection of the skin sensitivity of the opposite side of the body from tactile, pain, temperature receptors, interoceptive sensitivity and sensitivity of the musculoskeletal system - from muscle, articular, tendon receptors (Fig. 2).
Fig. 2. Scheme of sensitive and motor homunculus
(U. Penfield, T. Rasmussen). Enclosure section in the frontal plane:
but- the projection of the general sensitivity in the core of post-central ispud; b.- Projection of the motor system in the core of precentral winding
In addition to the somatosensory region I allocate somatosensory regionII smaller sizes located on the border of the intersection of the central furridge with the upper edge temporal sharein the depths of the lateral furrow. The accuracy of the localization of body parts here is expressed to a lesser extent. Well-studied primary projection zone is hearing bark(Fields 41, 42), which is located in the depths of the lateral groove (cross-headed hemiscores Geshal). The projection core of the temporal share also includes the center of the vestibular analyzer in the upper and medium temporal convictions.
IN baselinesituated primary visual area(Bark parts of wedge-shaped gyrus and tongue slices, field 17). There is a topical representation of retina receptors. Each point of the retina corresponds to its section of the visual bark, while the zone of the yellow spot has a relatively large zone of the representation. Due to the incomplete crossroads of the visual tract in the visual region of each hemisphere, the same ages of the retina are projected. The presence in each hemisphere of the retinal projection of both eyes is the basis of binocular vision. Near the field 17 is the bark secondary visual region(fields 18 and 19). Neurons of these zones are polymodal and respond not only to light, but also tactile and auditory stimuli. In this visual region, the synthesis of various types of sensitivity occurs, there are more complex visual images and their identification.
In secondary zones, the 2nd and 3rd layers of neurons are the main part of the environmental information and the inner environment of the body, which entered the sensory bore, is transmitted to its further processing into an associative boron, after which it is initiated (if necessary) Behavioral reaction with the obligatory participation of the motor cortex.
Motor cortexes.Select primary and secondary motor zones.
IN primary motor zone (Presencentral Cross, Field 4) There are neurons, innervating motionones of the muscles of the face, torso and limbs. It has a clear topographic projection of the muscles of the body (see Fig. 2). The main pattern of the topographic representation is that the regulation of muscle activity providing the most accurate and varied movements (speech, letter, facial expressions) requires the participation of large in the area of \u200b\u200bmotion cortex. An irritation of the primary motor cortex causes contraction of the muscles of the opposite side of the body (for the muscles of the head abbreviation can be bilateral). With the defeat of this cortical zone, the ability to be lost to thin coordinated movements by limbs, especially fingers.
Secondary motor zone (Field 6) is located both on the lateral surface of the hemispheres, ahead of the presencentral winding (premotor cortex) and on the medial surface corresponding to the cortex of the upper frontal winding (an additional engine area). The secondary motion cortex in the functional plan has a dominant value relative to the primary motorbate, carrying out the highest motor functions associated with the planning and coordination of arbitrary movements. Here is most recorded slowly increasing negative readiness potentialarising about 1 seconds before the start of movement. The bark of the field 6 receives the bulk of the impulse from the basal ganglia and the cerebellum, participates in the transcoding of information about the plan of complex movements.
Irritation of the field of field 6 causes complex coordinated movements, such as turning the head, eye and torso in the opposite side, friendly cuts of flexors or extensors on the opposite side. In Preblen Core, there are motor centers associated with the social functions of a person: the center written speech In the rear section of the middle frontal windows (field 6), the center of the Motor speech of the Brock in the rear section of the lower frontal winding (field 44), providing speech praxis, as well as a musical engine center (field 45), providing speech tone, the ability to sing. Motor cortex neurons receive afferent entrances through the thalamus from muscle, articular and skin receptors, from basal ganglia and cerebellum. The main efferent output of the motor cortex on stem and spinal engine centers are pyramid cells V layer. The main shares of the Big Brain bark are presented in Fig. 3.
Fig. 3. Four main shares of the cerebral cortex (frontal, temporal, dark and occipital); side view. They are located primary motor and sensory domain, motor and sensory areas of higher order (second, third, etc.) and associative (nonspecific) bark
Associative areas of the crust(nonspecific, intersensive, inter-cortex cortex) include the sections of the new large brain cortex, which are located around the projection zones and next to the motor zones, but do not perform directly sensitive or motor functions, so they can not be attributed to predominantly sensory or motor functions, these zone neurons have large Learning abilities. The boundaries of these regions are not indicated well. The associative bark is the phylogenetically the most young part of the new bark, which has gained the greatest development of primates and in humans. It has about 50% of the entire bark or 70% of neocortex. The term "associative bark" arose due to the existing idea that these zones due to the cortic-cortical compounds passing through them connect the motor zones and simultaneously serve as a substrate of higher mental functions. Basic associative cortex zonesare: dark-temporal-occipital, prefrontal bark of frontal fractions and a limbic associative zone.
The neurons of the associative bark are polyessence (polymodal): they are responsible, as a rule, not one (as neurons of primary sensory zones), but by several stimuli, i.e. the same neuron can be excited when irritating the hearing, visual, skin and Dr. receptors. The polyessence of the neurons of the associative bark is created by cortico-cortical connections with different projection zones, associative bonds of the Talamus. As a result, the associative bark is a kind of collector of various sensory excitations and participates in the integration of sensory information and in ensuring the interaction of sensory and motor areas of the crust.
Associative areas occupy the 2nd and 3rd cellular layers of the associative bark, on which there is a meeting of powerful single-scale, different-scale and non-specific afferent flows. The work of these brain bark departments are necessary not only for successful synthesis and differentiation (selective distinctions) of the person perceived by a person, but also for transition to the level of their symbolization, that is, for operating the words and use the words and use them for distracted thinking, for the synthetic nature of perception.
Since 1949, D. Hebba hypothesis was widely fame, which postulates the coincidence of the presynaptic activity with the discharge of post-synptic neuron as the condition of the synaptic modification, since not any activity of synapse leads to the excitation of postsynaptic neuron. Based on D. Hebb's hypothesis, it can be assumed that the individual neurons of the associative cortex zones are connected with a variety of ways and form cell ensembles that allocate "appeals", i.e. corresponding to unitary forms of perception. These links, as noted by D.Hebb, are so well developed that it is enough to activate one neuron, as the entire ensemble is excited.
The device performing the role of the wake level regulator, as well as using selective modulation and updating the priority of a particular function, is a modulating brain system, which is often referred to as a limbic-reticulous complex, or an upward activating system. The nerve formations of this apparatus include limbic and nonspecific brain systems with activating and inactivating structures. Among the activating formations, first of all, the reticular formation of the mid-brain, the rear hypothalamus, the blue spot in the lower sections of the brain stem. Inactivating structures include the precortic region of the hypothalamus, the seam kernel in the brain barrel, frontal bark.
Currently, on tamlamocortical projections, it is proposed to allocate three main associative brain systems: talamum, Talamolobnya and talamumochnyh.
Talamum system represented by associative areas of the parietal bark that receive the main afferent entrances from the rear group of associative nuclei of the Talamus. The Dark Associative Cora has efferent yields on the thalamus kernels and the hypothalamus, in the engine bore and the core of the extrapyramidal system. The main functions of the talamum system are Gnosis and Praxis. Under gnocompon understand the function of various types of recognition: forms, values, values \u200b\u200bof objects, understanding of speech, knowledge of processes, patterns, etc. The estimation of spatial relations is related to the gnostic functions, for example, the mutual location of the items. In the parietal cortex, the center of stereogenis is allocated, which ensures the ability to recognize items to the touch. A variant of the gnostic function is the formation of a three-dimensional body model in the consciousness ("body scheme"). Under praxis understand targeted action. Praxis's center is located in the suprakkaya urinet of the left hemisphere, it provides storage and implementation of the program of motor automated acts.
Talalamolobic system represented by associative zones of a frontal bark having a basic afferent entrance from the associative medium-appliance core of Talamus, other subcortical nuclei. The main role of the frontal associative bark is reduced to the initiation of basic systemic mechanisms for the formation of functional systems of targeted behavioral acts (P. K.Anokhin). The prefortional area plays a major role in developing a behavior strategy.Violation of this function is especially noticeable when it is necessary to quickly change the action and when there is some time between the task and the beginning of its decision, i.e. I have time to accumulate stimuli, requiring the right inclusion in a holistic behavioral reaction.
Talamumian system. Some associative centers, for example, stereoognosis, Praxis, include the sections of the temporal bark. In the temporal crust there is a hearing center of speech Wernik, located in the rear departments of the upper temporal winding of the left hemisphere. This center provides speech gnosis: recognition and storage oral speech both own and strangers. In the middle of the upper temporal winding, there is a center for recognizing musical sounds and their combinations. On the border of the temporal, rare and occipital fraction is the reading center, providing recognition and storage of images.
A significant role in the formation of behavioral acts is played by the biological quality of unconditional reaction, namely, its importance for saving life. In the process of evolution, this value was enshrined in two opposite emotional states - positive and negative, which in humans form the basis of its subjective experiences - pleasure and displeasure, joy and sorrow. In all cases, targeted behavior is built in accordance with the emotional state that has arisen under the action of an irritant. During behavioral reactions of a negative nature, the voltage of vegetative components, especially the cardiovascular system, in some cases, especially in continuous so-called conflict situations, can achieve a great force that causes a violation of their regulatory mechanisms (vegetative neurosis).
In this part of the book, the main general issues of analytical synthetic activity of the brain, which will allow for the following chapters to present private issues of physiology of sensory systems and higher nervous activity.
1.1. From the history of the doctrine on the localization of PF
The idea that various parts of the brain have a different specialization, it is not functioning equally, it has arisen a long time ago, long before the appearance of neuropsychology as a scientific discipline. First of all, it is associated with the name of the French neurologist Franz Gall (F. Gaal), which was the first to suggest that the brain mass alone consists of many organs. HED, who wrote work, in which the history of scientific thought is traced during the century (from the middle of the XIX to the middle of the 20th century), reports interesting information About how this opinion was formed by F. Gall.
As a child, F. Gall grew and studied with a boy, which was much easier to teach. If you need to learn something by heart, this boy and some other school students significantly overtook him in many subjects, but at the same time lagging behind him written works. F. Gall noticed that these disciples with good memory on oral texts Big "bullish eyes" and cones over the abnormal arcs. On this basis, he tied the ability to easily memorize with good memory for words and concluded that this ability is located in the part of the brain, which is behind the orbits. So there was a thought that the memory of the word is located in the frontal shares of the brain. All his life, he paid attention to the structure of the skull different people And they associated with its features of those or other abilities. On the basis of these views, a whole area of \u200b\u200bknowledge arose - Franology (from Greek. - "Soul"), containing instructions on how to determine the nature and ability of a person in the form of a skull. F. Gall began to call the founder of phrenology, considered, and continuing to be considered a dubious direction scientific research. F. Gall's views were regarded so dangerous for religion and morality that his lectures were banned by the Kaiser's own letter. However, the phrenological representations of F. Gall, no matter how appreciated them, played a big role. They laid the beginning of the idea of availability in the human brain specialized departments,each of which performs its specific function. It did not allow to more count the brain with a single homogeneous mass.
By the 60s of the XIX century, the situation in neurological science was administered to the limit. Questions about the localization of the function in the brain rose in scientific debates for any occasion. Despite the works of F. Gall and his followers, the main issue remained the question of whether the brain functions as one or it consists of many organs and centers acting more or less independently of each other. The problem of localization of speech was most acute. The widespread opinion was responsible for frontdepartmentsbrain.
F. Gall believed that other MPFs also had a certain brain localization, he differed the memory of things, places, titles, grammatical categories and had them in different areas of the brain. As will be shown later, these views were progressive and in many respects were subsequently confirmed by F. Gall's opinion that the higher ability hierarchies have the same defined localization in any of the sections of the brain, turned out to be insolvent. It turned out that such psychological qualities like "courage", "sociability", "love for parents", "ambition", "instinct of continuation of the kind", etc., are not located in the "individual bodies" of the brain, as F. Gall claimed.
Nevertheless, the idea of \u200b\u200blocalizationism received powerful development. In August 1861, the French neurologist Paul's Paul at the meeting of the Anthropological Society of Paris reported his famous case, proved that damage to a separate brain area, i.e. Local focus of the lesion can destroy such a function as speaking by causing its loss called aphasia. At the opening of the skull in P. Brock's patient, by the LEBRAN surname (Lebran), whom he observed 17 years old, was detected by the destruction of a large portion of the left hemisphere of the brain, covering mainly a routing zone. Based on the fact that the most affected were speech movements, this area began to consider the center motor speech,and amphazia arising from his defeat, motor aphasia.
10 years after the P. Brock's report at the meeting of the same society, the German neurologist Karl Vernice (K. Wernice) presented another case of local brain damage, and also in a patient with Aphazia. Patient K. Vernika, although he kicked up, could speak himself, but practically did not understand the speech of other people. The focus of the defeat covered the most part from this patient temporalthe shares of the left hemisphere. This form of aphasia K. Vernika gave the name of the sensory, and the affected area of \u200b\u200bthe brain - the center of the sensory speech, and the aphasia, arising from his defeat, designated as sensory.So the doctrine of the localization of PF was largely advanced forward.
Soon, others were added to the center and sensory speech centers. Interest in the question of the local brain lesions increased in many countries. The localizationist ideas of F. Gall received even more powerful sound, and in science began a fascination with centers, which led to a member of the expression of Hand, to the construction of schemes and diagrams. The brain became dismissed into many areas reflecting the ideas of the time about the motley functional specialization of the brain zones. The famous patchwork map of the brain appeared, where many, including those acquired, addiction, for example, to a particular food, to one or another music, etc., were attached to the character traits, localized F. Gallem. Thus, the idea of \u200b\u200blocalization function was brought to the absurdity (Fig. 9cm. color incl.) Naturally, there were serious objections of contemporaries that believed that the brain could not function so "fractionally" these scientists who were opposition to narrow local polishes, called antilocalysts. The most vivid representative of this flow was the French scientist Pierre Marie (P. Man). He believed that the functional specialization of the brain could not be so narrow and that actually the speech area is only the left temporal share.
Some scientists occupied an intermediate position. Their bright representative was X. Jackson. In his opinion, each difficult organized function is represented in the brain at three levels: 1) lower (stem or spinal); 2) average (in motion or sensory sections of the brain cortex); 3) Higher (frontal lobes of the brain). These ideas are relevant and now, however, with some clarifications, which will be discussed below. X. Jackson belongs to the famous statement that locate the function and localize the defeat- not same.This means that as a result of the brain damage in one place, the inferiority of functioning in another may arise, and this no longer coincided with the representations of narrow localizationism.
1.2. Modern ideas On the localization of the PPE (the idea of \u200b\u200bthe dynamic localization of the PF)
The accumulated experience in the effects of local brain lesions served as the basis for the emergence of the theory of the system structure of the speech function and its dynamic localization in the brain, which laid the end of the spending more than a century of leaps and antilocalysts. This theory was created by the works of domestic neurologists and neurophysiologists N.A. Bernstein, P.I. Anokhina, A.I. Ukhtomsky, psychologist L.S. Vygotsky, founder of neuropsychology A.R. Luria, etc.
Term "Dynamic"in relation to localization, it is due to the fact that, according to the ideas of these scientists, the same brain zone can be included in a variety of cerebral ensembles, i.e. Dynamically change your position and role. When implementing one function, it functions together with the same zones, and when carrying out another - with others, like colored glass in a children's toy kaleidoscope:the glass are the same, and the image is different - depending on changes in their combination. In each concrete ensemble of the brainstones involved in the implementation of the function, the role of each of them is specific (Fig.I.).
Such an ability of nervous structures - to be differently involved in different functions - is a bright embodiment of the biological principle of savings, which allows you to make the most optimal way to implement one or another type of mental activity.
Despite the complexity of the MPF brain organization, so much more is known about what functional specialization has different areas Brain, which is reflected in the brain special cards.
The zones indicated in them are the result of studies not only within the framework of neuropsychology, but also much more pressing scientific research.
Outstanding domestic neurophysiologist PK Anokhin defines each functional system as a certain complex, a set of afferent alarms, "which through the action acceptors directs the execution of its function."
^ Dynamic Localization of Higher Mental Functions
Fig. I.
Legend:D is the right hemisphere, S - left hemisphere, F is a frontal share, o - occipital share, T - temporal share.
PC. Anokhin revealed the most important pattern of higher nervous activity, namely, the external afferent irritants entering the central nervous system distributed in it not linearlyas was customary to be considered earlier, and enter subtle interactionviya with other afferent excitations.These "associations" can be replenished with new connections enriched them. The activity as a whole is modified. It is the association of afferentations is an indispensable condition for the decision.
Thus, afferent synthesis as a mechanism of higher mental activity PK. Anhin attached paramount importance. Finally, it is impossible not to dwell on the fact that he introduced into science the concept of "reverse affaentations", i.e. The mechanism that informs about the results of the actual action so that the body appreciates them. Currently, this idea has developed into a whole scientific and practical direction of medicine, called Bosom (biological feedback).
A huge contribution to the understanding of the Localization of the PPE made the teachings of A.R. Luria about the Molden Organization of PVF, which was the result of scientifically practical work with a colossal number of cranial injuries in almost healthy young people, whom "put" the second world War. This tragedy made it possible to see in what kind of place the brain is damaged, and fix what function "falls" at the same time. Confirmed single finds of the classics of neurology (P. Brock, K. Vernik et al.) The fact that there are local MPFs or their fragments, i.e. Those that can be carried out do not at the expense of the whole brain, but any particular area. The results obtained brought our country in the art for advanced frontiers in the world, allowing to create, as already mentioned, a new scientific discipline - neuropsychology.
L.S. Vygotsky stressed that the problem of the Mozgian organization VPF is not reduced only to define those zones that implement them. Each HDP is essentially the center of two functions: 1) a specific, associated mental activity ascribed to it; 2) Nonspecific, making this area capable of participating in any form of activity. The specific function is never carried out by any one section of the brain, but is the result of its integration with other brain areas. Thus, any function correlates with brain activity as a figure with a background. At the same time hp Vygotsky emphasized that the integrative essence of functions does not contradict their differentiation. On the contrary, he considered differentiation and integration not only do not exclude each other, but rather, they assume one other and in a certain attitude are in parallel.
Other essential features of ideas about the localization of HPP L.S. Vygotsky considered: 1) the variability of interfunctional relations and relationships; 2) the presence of complex dynamic systems in which a number integrated elementary functions; 3) a generalized reflection of reality in consciousness. He believed that all these three conditions reflect the universal law of philosophy, which states that a dialectical jump is not only a transition from inanimate matter to animation, but also from the feeling to thinking the extensiveness of the automation method of performing the action of HP Vygotsky considered the conditioned by the hierarchical level on which the function is carried out.
Finally, it is fundamentally important to consider the belief of L.S. Vygotsky is that "development goes upwards, and the decay is downward." This winged phrase L.S. Vygotsky reaches such a level of generalization when the thought becomes almost indisputable. Developing, the child comprehends the world from simple to complex. In the case of loss (decay) of the function, the person returns to more elementary knowledge, skills and skills that serve as basic for compensation processes.
From the representations of L.S. Vygotsky on the patterns of development and decay directly follows the following position: the same localized lesions lead in a child and adult to completely different consequences. With developmental disorders associated with any brain damage, it suffers primarily the nearest top in relation to the affected area, and in an adult, i.e. When decaying the function, - on the contrary, the nearest lower, and the nearest top suffers relatively less.
The concept of local MPF is largely developed by N.P. Bekhtereva, which has developed the concepts of flexible and hard links of cerebral systems. To rigid links N.P. Bekhtereva attributed most of the regulation regulations of vital internal organs (cardiovascular, respiratory and other systems), to the second - the area of \u200b\u200banalysis of external signals (and partly internal) peace, depending on the conditions in which a person is located. N.P. Behtereva was revealed that the change in conditions leads to significant changes in the work of the brain structures, providing one or another function, and most importantly, which brain zones are switched off or are included in operations. These data showed that the PF location may vary not only from age indicators, when some links seem to die, while others are connected, or from the individual characteristics of the brain organization of mental activities, but also on the conditions in which activities proceed. From here, in addition, far-extended conclusions are followed about compliance with the necessary conditions for education, training and in general human life, as well as the selection of optimal conditions for these processes.
French scientists J. De Aguriagere and X. Ekan draws attention to the fact that the value of the clinical concept of localization is extremely large, but only if it takes into account that different functions are localized in different ways. Anatomical, physiological and clinical data make it possible to establish that the localization of some functions is character somatetopia(coincide with the projection in the brain of the informative part of the body). These include the areas of analyzers, as well as various types of gnosis, Praxis, including oral-articulation. Some types of such functions (for example, a body scheme) are significantly varying by structure and localization, depending on the location of the focus of the lesion within the zone of their implementation, or, depending on the individual organization of brain activity in different patients. This is evidenced by differences in the structure of the defect in their defeats.
According to J. De Ažuriraherra and X. Ekaen, it is fundamentally important the position of X. Jackson on the positive and negative symptoms of the Violation of the PPF. Under the negative means the fallout of the function, and under positive - the release of the underlying zones, which were under the control of higher. To this J. De Azuriagerra and X. Ekaren add that the release of the underlying areas of the brain and the corresponding functions is associated with a balance of equilibrium between the type of response to the outer stimuli with the lower and upper zones of the brain.
Speaking about the problem of localization, it is impossible not to take into account the fact that the variety of brain lesions (vascular, tumor or traumatic) determine the differences in the symptom complex of developing disorders in the symptom complex of developing disorders.
^ Questions on the topic "Localization doctrine":
What idea about the brain representation of the PPE made works by the classics of neurology (P. Broca, K.wermce, etc.)?
What do the terms "Localizationism" and "antilocalizationism" mean?
What does the term "dynamic Localization of the PF" mean?
What are the main provisions of hp Vygotsky on the localization of the PPE, their structure, development and decay?
What material was created by the doctrine A. R. Luria?
Chapter 2. Brain structure
2.1. General ideas About the brain
In order to consider modern performances not only about the psychological structure of the Human MPF, but also their brain organization, it is advisable to apply to modern ideas about the brain as a whole.
The human brain is the top department of the central nervous system (CNS). Between it and the lower department of the CNS (spinal cord) there is no border, which would be expressed anatomically. The end of the spinal cord and the beginning of the head conditionally serves as the top cervical vertebra. From here it is clear what an important role to work the entire nervous system is the condition of each of the parts of the central nervous system. In particular, the fact that its "nervous axis" (head and spinal cord) is one, determines the dependence of the brain's work on the state of the dorsal, especially in childhood. This, in turn, suggests that educational measures to strengthen the spinal column in the most early period Life, as well as on the development of proper posture in the next time they are necessary.
Various parts of the brain are not the same on the hierarchy. In neuropsychology, their anatomical division into blocks, the teachings of which were developed by A.R. Luria. Each of them is compiled by various brain structures, which will be discussed further.
The main part, the largest area, is the brain (Fig. 1, 2,color incl.) It has: a) surface folds that are indicated as furrows;b) deep folds indicated as slit;c) convex crests on the brain surface - area.
Cracks separated the brain on shares (fig. 2,color incl.) Cutting shares to share the sections even more differentiated in functionality.
The main units of the nervous system are nervouscells - neurons (Fig.9 cm. incl.) Like other cells of our body, neuron contains a body with a core located in the center and the processes that are called nevitat.Some of the neurites transmit nerve impulses to other cells, others - take them. Transmitting processes are long. These axons accepting are short. Etodhendrites. Each cell has one axon and many dendrites.
Neurons made up a gray matter of the brain. They are extremely diverse in shape and functional purpose. Their processes, axons that transmit information are a white brain substance. Akson are myelinated, i.e. Covered with fat myelin, which increases the rate of transmission of nerve impulses. Aksones are reliably protected by mitochondria classes, representing support cells that form a white fat (myeline) layer - glius. Glya is not solid. It has interceptions called Ravier interceptions. They facilitate the passage of nerve pulses from the cell to the cage. The same role is played by bubbles (neuromidiators) located in the end of axon. Glial cells do not conduct nervous impulses. Some of them feed neurons, others protect against microorganisms, the third regulate the flow of the spinal fluid.
In the body of the cell there are other structures providing life. The most important of these are Ribosomes (Nissl Taurus). Ribosomes have the shape of the granules. They synthesize proteins, without which the cage cannot survive.
Despite the complexity of the cellular device of the brain, the laws of its functioning are largely studied and are of extreme interest.
Spanish scientist Santiago Ramon-I-Kahal gave a surprisingly poetic description of the brain from the point of view of the components of its nerve cells. "The Garden of Neurology," he wrote, "represents a researcher who is exciting, no incomparable performance. In it, all my aesthetic feelings found complete satisfaction. As an entomologist, haunting brightly colored butterflies, I hunted in the colorful gray garden with their subtle, elegant forms, mysterious butterflies of the soul, whose wings beating, perhaps, once - who knows? - Clears the secret of spiritual life. "
The brain of the newborn child has 12 billion neurons and 50 billion glial cells, an adult - 150 billion neurons (according to I.A. Skvortsov). If they stretch into a chain, or rather, in the bridge, then it can be bought on it to the moon and back.
The size of each cell is extremely small, but the range of their differences on this feature is quite large: from 5 to 150 microns. During his life, a person loses a certain number of cells, but in comparison with their total number of losses are negligible (approximately 4 billion neurons). If quite recently it was believed that the nerve cells are not restored, then at present this truth has ceased to be absolute. Neurobiologist S. Weiss from Canada in 1998 expressed an opinion founded on the studies conducted by him that neurons can be recovered. True, the mechanism of such restoration takes place not in all people and not under all conditions. The reasons for this continue to be revealed, but the very fact that it is possible is one of the rarity sensational.
Before the secrets of the ripening and functioning of nerve cells were opened, it was believed that the nerves were empty (hollow) tubes. They move the flows of gases or liquids. Isaac Newton first moved away from these ideas, stating that the transmission of the nervous impulse carries out a vibrating ether medium. However, even closer to the true situation of things, the Italian researcher Luigi Galvani approached. In the scientific world, as well as outside it, a casus is well known, which helped him open the bioelectric nature of the functioning of the nervous system.
This refers to the broken paw just undergoing the preparation of a frog, which accidentally came under electric current And it began to shrink (twitch). Thus were laid the foundations of the most important science of the brain - neurophysiology studies the electric biopotentials of the brain.
It is widely known that nervous cells are combined on the network, which are also called nervous chains. Each neuron has approximately 7 thousand such chains. In the cell chains, information is transmitted to the cell. The site of the exchange is the places of the axon (long cell of the cell) of one cell and the dendrite (short process) of another cell. Neuron transmits excitation to another neuron through one or multiple contact points (synapses) - (Fig. 10,color incl.) When the pulse reaches the synaptic assembly, a special chemical substance is released - the neurotransmitter. It fills the synaptic slit and spreads the nervous impulse for a significant distance. The more synapses, the more room in the sense of the memory of the brain "computer". Each nervous cell receives impulses from many hundreds, and even thousands of neurons.
According to the ideas of neurophysiology, the velocity of the electric current on the nerve wires is equal to the speed of the screw aircraft - 60-100 m / s. Typically, the distance from Sinaps to Sinaps is 1.5-2 m. Nervous impulse overcomes it for 1/100 fraction of a second. Consciousness does not have time to fix this time. The speed of thought is thus above the speed of light. This is reflected in many folk sources. Recall, for example, a princess, which testing good well done, makes him riddles, and in particular, this: "What is the fastest in the world?" (Bearing in mind as a response - thought).
Nervous cells do not share how other cell cells do, so if they are damaged, they are most often dying.
Despite the fact that the nervous impulse has an electric nature, the relationship between neurons is provided chemical processes. For this, there are biochemical substances in the brain - neurotransmitters and neuromodulators. At that moment, when the electrical signal comes to synapse, the corresponding transmitters are released. They, as a vehicle, deliver a signal to another neuron. Then these neurotransmitters are disintegrated. However, on this process of transmission of nerve pulses does not end, because Nervous cells are behind the synaps, activate, and postsynaxic potential occurs. It gives rise to a pulse moving towards another synapse, and the process described above repeats thousands of people once. This allows you to perceive and handle the colossal amount of information.
In many publications on neurology and neurophysiology, it is noted that the most complicated brain activity is ensured, in essence, simple means. Some of the authors note that this simplicity reflects the universal law "Achievements of great complexity through multiple transformations of ordinary elements" (E. Goldberg). Similarly, this, many words in the language consists of a limited number of sounds of speech and alphabet letters, countless musical melodies - from the small number of notes, genetic codes Millions of people are provided with a finite number of genes, etc.
2.2. Anatomical and functional discharge of the brain
2.2.1. Fields of the cortex of the brain
According to the prevailing ideas, the bark of the brain has six main layers, each of which consists of various in the form and size of nerve cells. This anatomical fact has, however, is not so important for understanding neuropsychological phenomena, as a functional differentiation of the crust for three main types of fields - primary, secondaryand tertiary (Fig. 8,color incl.) They differ among themselves on the hierarchy. The most elementary are primary, more complex on the structure and operation - secondary, and, finally, the most difficult on these features are tertiary fields.
The fields of each level have their numbering, which is indicated on cytoarchitectonic brain cards. The most common of them is the Brodman map (Fig. 6,color incl.)
Primary fields -these are the "cortical ends of the analyzers" and, as previously reported above, they function from nature, congenital. Their localization depends on how the analyzer they relate.
Primary fields located in frontal share(to central ispuncuts), namely, the fields 10, 11, 47 are configured to prepare and execute motor acts relating to the physical level.
Primary fields auditorythe analyzers are located mainly on the inner surface of the temporal fractions of the brain (fields 41, 42), a kinesthetic (sensitive as a whole) near the central (rollandal) groove, in a dark share (fields 3, 1 and 2).
Primary sensitive(tactile) fields are characterized by the fact that they are projection zones regarding certain parts of the body: the upper departments take sensitive signals (sensations) from the lower extremities (legs), the average handle the sensations from the upper limbs, and the bottom - on behalf, including the speech apparatus departments (Language, lips, larynx, diaphragm). In addition, the lower departments of the parietary projection zone take sensations from some internal organs. The body projection algorithm in the front brain block is the same as in the back. They are also projection, but already in relation to non-sensitive (kinesthetic), and motor functions. The main difference between the projection zones from others is that the size of one or another body part is determined not anatomical, but functional significance.
Primary brain cells in earlier ontogenesis are functionally functionally functionally, like separate worlds in space. So, the child recognizes the voice of the mother, but does not recognize her face if she is silent. Particularly often disagreement of auditory and visual impressions at the level of sensations is observed with respect to the face of the Father, which the babies see less often than the face of the mother. In the literature, there are cases when the child, seeing the face of the Father, begins to cry out loudly, until he speaks. Gradually, information connections (associations) are laid between the primary fields of the brain cortex. Thanks to them, the experience of sensations is accumulated, i.e. Elementary knowledge of reality appear. For example, the child "learns" that sucking the chest or bottle quenches the feeling of hunger.
2.2.2. Modally-specific brain bark
Primary fields are homogeneous by cellular composition, so they are indicated as modally-specific.The olfactory fields contain only olfactory nerve cells, auditory - only auditory, etc. Despite the versatility of physiological and biochemical mechanisms that ensure the work of the brain, its various departments function differently, i.e.have a different functional specialization,representing different modalities.
Secondary fields are also modally specific, although less homogeneous than primary. The cells of the prevailing modality are enclosed by other modalities. Tertiary being with overlapping zones, not only the cells of hollow modalities, but also their whole zones. Based on this, they are denoted as polymodalor outmade.Thanks to the functioning, the most complex PVF is being implemented, and in particular certain speech components. Modally specific brain structures contribute their own and most importantly, the total contribution.
Secondary and tertiary cortex fields, unlike primary, have features of functioning depending on lateparalizationthose. Location in the one or another of the hemisphere of the brain. For example, the temporal shares of different hemispheres, referring to the same, namely, the auditory modality, perform different "work". The temporal share of the right hemisphere is responsible for the treatment of non-echo noise (by nature published, including "animal voices" and the voices of people, subjects, including musical instruments and the music itself, which can be considered higher species Sneb noise). The temporal share of the left hemisphere carries out the processing of speech signals. In addition to differences in the specialization of the temporal stakes of the brain relating to different hemispheres, here you can see and so characteristic of the nature of the "protection" principle of the most important functions, and the more such an important and necessary any person as it is.
Differences in the functional specifics of primary, secondary and tertiary fields determine the differences in their ability to replace each other (compensate) in the case of pathology. The destruction of the primary fields is not filled, i.e. Lost physical hearing, vision, smell and other are not restored. In the very recent, this provision is subject to revision in connection with the study of the regenerating role of so-called stem cells. The functions of damaged secondary fields are subject to compensation carried out by connecting other, "healthy" brain systems and restructuring the method of their activities. The functions of the victims of the tertiary fields are compensated relatively easily due to polymodality, which allows to rely on a powerful association system stored in each of them between them. It is necessary, however, to remember that age thresholds and the time have been important in this case when recovery activities have begun. The most favorable early age and timely start of therapeutic correctional and recovery measures.
Functionally all three types of bark fields correspond to each other vertically: the functions of primary, the functions of secondary, and above the secondary - tertiary are awaited. However, they are not anatomically arranged in a similar way, i.e. each other. Primary fields make up a kernel of a particular analyzer, which wears in neuropsychology modality.Secondary fields are further from the nucleus, i.e. shifted to the periphery of the zone, and tertiary - even further. Prospects to the kernel and sizes of different field hierarchies: primary occupy the smallest area, secondary - large, and tertiary - the largest in size. As a result, the latter are superimposed on each other, forming the so-called "overlap" zones. These include, for example, the most important TRO area for the TRF - temporahs - temple; PANETAHS - the topics; Oxipitahs - headings).
In the implementation of higher mental functions, the auditory, visual and tactile bark takes the greatest participation.
The auditory area refers to the sensory (perceive) core of the brain. The main department is, as indicated by A.R. Luria temple arealeft hemisphere. It includes various sites on the hierarchy, which causes the complexity of its structural and functional organization. The most significant of them is nuclearthe zone of the auditory analyzer, providing physical hearing (fields 41, 42), is the primary hearing bark fields. Next from the kernel is located peripheralsection of the zone (tertiary field 22). Behind them follows the area medium templeborder with dark and occipital regions (tertiary field 21 and partly with a tertiary field 37). Middle Affairs(extraordinary) departments of the temporal share are represented by tertiary bark and are more complexly organized. They, according to the ideas of neuropsychology, are responsible for the perception of non-single sounds of speech and words, but their series, and closely connected by numerous associative fibers and with visual bark, which necessitates its participation in the realization of the word. In the zone of the 37th field there is also a small area of \u200b\u200boverlapping (overlaying on each other of the temporal and occipital bark).
According to E.P. COC, presented in her monograph "Spectatical agnosies", written back in 1967, this area is most adapted for mastering and further ownership of the word. E P. Kok emphasizes that the word is the unity of the visual image of the subject and its "sound shell", and, therefore, the presence in one zone of the brain of the auditory and visual bark contributes to the development of strong figurative-verbal associations.
Word and It visual image become firmly soldered.
The stronger this "spike", the more reliably the word is stored in memory and, on the contrary, than it is weaker, the easier it is for the word forgotten (amnesia words).
A.R. Luria writes that the auditory perception includes the analysis of the synthesis reaching the signals to the subject in the first stages of their receipt.
It follows from this that the process of perception of speech is based not only in physical hearing, but also on the ability to analyze heard. The functions of this analysis are assigned mainly by the secondary temporal field 22 located in the upper temporal area.
It is precisely how it is responsible for the discrete perception of speech sounds, including what is fundamentally important, and for the allocation of acoustic images of signaling (sense-distingucting) signs that have called phonamatic.
It is also recognized that the phonematical language system is formed with the direct participation of the articulation apparatus, thereby producing acoustic and articulation bonds.
In addition to the actual cortical level of the auditory zone, there is a basal hearing field 20 and a medial ("deep") temple. This brain department is included in the so-called "Circle of Peripets" (Hippocampus - the core of the viewing bulb - partitions and mamillar bodies - hypothalamus).
Medical departments of the temple are closely associated with non-specific formations of a limbico-reticular complex (a brain department regulating the tone of the bark) - (Fig. 12,color incl).
Such a composition of the medial temple causes its most important feature - the ability to regulate the state of activity of the cortex of the brain as a whole, the processes of neurodynamics, the vegetative sphere, and within the framework of the highest mental activity - emotions, consciousness and memory.
^ Spectator
The primary visual bark extends on both sides along the spur furrow on the medial surface of the occipital proportion and applies to the convertive surface of the occipital pole. Nuclear zone spectatorthe crust is the primary cortical field 17. The secondary fields of the cortex (18, 19) make up a wide visual sphere. In relation to the principle of functioning of this zone, the same revision of the principles of the reflex theory of sensations, which was mentioned in the illumination of the functional specialization of temporal (auditory) bark was relevant. As a result of this revision spectacular perception it became not considered as a passive process, but as an active action
The main differences in the activity of the visual, like a skin-kinesthetic, dark crust, is that the signals perceived by it are not lined up into successive series, but are combined into simultaneous groups due to this, complex visual differentiations are provided, which implies the ability to allocate thin optical signs during focal lesions of this area. There is often somewhat found in clinical practice. optical agnosia.Back in 1898 E LesWauer(E Lissauer) marked it as "apperpety spiritual blindness" and noted that patients suffering from her do not recognize visual images of even familiar objects, although they can recognize them to the touch. Subsequently, the optical visual agnosia was studied in detail and described by E. P. Kok, L with flowers, etc., which showed its connection with amnistic aphasia
In the highest hierarchy of the dark-occipital core, which is areas where the central ends of optic and tactile analyzers are connected ("overlapping zones"), the incentives of the external environment are combined into "simultaneous syntheses", allowing to perceive one-time complex images, for example, plot patterns. According to the ideas of neuropsychology, the defeat of this area leads to violations simultan visual gnosisand systemically conditioned semantic apha.
^ Tactile bark
Synthesis of tactile signals carry out darkthe bark departments of the brain, similar to how the dark-occipital region carries out optical perception Nuclear zonethis analyzer is the area of \u200b\u200bthe rear central winding Primary fieldstactile bark provide skin-kinesthetic sensitivity at the physical level (field 3) Secondary ocean field(2, 1, 5, 7) specialized in relation to the complex differentiation of tactile signals (stereogeneity) due to them it is possible to recognize items to the touch.
^ Motor Cora
Motor "Analyzer" is understood as consisting of two, jointly working brain bark departments (post-week and presenter) together they constitute shensekornju area of \u200b\u200bthe bark.
The post-central bark, or, otherwise, the Lower-mounted bark, along the primary fields (10, 11, 47), takes tactile signals and processes them into tactile sensations, including speech
At the level of secondary fields (2, 1, 5, 7), it ensures the implementation of individual pose - kinesisy of the body, limbs, speech apparatus
Within frontblock brain of the left hemisphere for speech function The most significant is the front central expanser - primorous barkat the level of secondary fields (6, 8), it ensures the implementation of various motor acts, which are a series of consecutive movements and the name dynamic or, otherwise, efferent, praksisaIt, in turn, is the second, in addition to the afferent, arbitrary motor link. It is important that the premotor bark is capable not only to build, but also memorize motor sequences (kinetic melodies), without which within speech activity It would be impossible to smoothly utter words and phrases.
At the level of the tertiary field 45, the motor coo provides the ability to create programs of various activities. Due to this area, operating with typical programs of developed actions, including speech, for example, syntax models of proposals.
Below is the table of the numbers of the brain fields of various levels (by Brodman)
table 2
| ^ Mo Distance | Audio | Summary | Tactile | "Motor" |
||||||||
| Type of field of crust | I. | II. | III | I. | II. | III | I. | II. | III | I. | II. | III |
| № Field | 41, | 22. | 21, | 17. | 18, | - | 3 | 2,1, | 39, | 10, 11,47. | 6,8. | 45. |
The final brain.
Big large hemispheres of the brain. Localization of functions in the cerebral cortex. Lymbatic system. EET. Likvor. Physiology of the GNI. The concept of the GNI. The principles of the reflex theory of Pavlov. Difference conditional reflexes from unconditional. The mechanism for the formation of conditional reflexes. The value of conditional reflexes. I and II signal systems. Types of GND. Memory. Physiology sleep
Finite brain Submitted by two hemispheres, which include:
· cloak (bark),
· basal kernels
· olfactory brain.
In each hemisphere allocate
1. 3 Surface:
· Uppertelteral,
· Medial
· Low.
2. 3 the edges:
· Upper
· Nizhny,
· Medial.
3. 3 pole:
· Front
· Growing,
· Temporable.
Cerebral cortex forms a protrusion - area.Between the convolutions are located furrows. Permanent furrows share every hemisphere on 5 dollars:
· Lobal - contains motor centers,
· Dark - centers of skin, temperature, proprioceptive sensitivity,
· Zatilochny - visual centers,
· Temporable - hearing centers, taste, smell,
· Islet - higher centers smell.
Permanent grooves:
· Central - located vertically, separates the frontal share from the parietal;
· Side - separates the temporal and dark stakes, in its depth it is located island, limited by a circular furrow;
· The dark-occipital - located on the medial surface of the hemisphere, separates the occipital and parietal shares.
Olfactory brain - Contains a number of formations of various origin, which are topographically separated into two departments:
1. Peripheral department(Located in the front of the bottom surface of the brain hemisphere) :
· Oplanny bulb,
· Obligating tract
· Olfactory triangle,
· Front crooked space.
2. Central Department:
· Vaulted (paragapocampal) Crochet shock (front of a vaulted winding) - on the lower and medial surface of large hemispheres,
· Hippocampus (convolution of the sea horse) - located in the lower rog of the side ventricle.
Brain bark (raincoat) - Is the highest and most young CNS department.
Consists of nerve cells, processes and neuroglia area ~ 0.25 m 2
For most parts of the cerebral cortex, the six-layer arrangement of neurons is characterized. The bark of large hemispheres consists of 14 - 17 billion cells.
Cellular structures of the brain are presented:
Ø Pyramid - mainly efferent neurons
Ø spindle-shaped - mostly efferent neurons
Ø star - perform afferent function
The processes of nerve cells of the cerebral cortex associate its various departments among themselves or establish the contacts of the large hemispheres with the underlying departments of the central nervous system.
Form 3 types of communication:
1. Associative - Connect various sections of one hemisphere - short and long.
2. Commission - Connect most often the same sections of two hemispheres.
3. Conductive (centrifugal) - connect the bark of the brain with other departments of the central nervous system and through them with all organs and tissues of the body.
Neuroglia cells play a role:
1. Are supporting tissue, participate in the exchange of substances of the brain.
2. Regulate the bloodstream inside the brain.
3. It is isolated neurospex, which regulates the excitability of neurons of the cerebral cortex.
Functions of the cortex of the brain:
1. Carries out the interaction of the body with environmental Due to unconditional and conditional reflexes.
2. are the basis of the highest nervous activity (behavior) of a person.
3. Implementation of higher mental functions - thinking, consciousness.
4. Regulates and combines the operation of all internal organs and regulates such intimate processes as the metabolism.
Hemisphere
Gray substance
1. Bark 2. Cores
The problem of localization of functions in the cerebral cortex
The most pronounced form ... Attempt to localize individual mental functions in the isolated sections of the brain received by F. A. Gall, whose ideas were found in their time very widespread.
Gall was one of the largest anatoms of the brain of his time. He first appreciated the role of a gray substance of large hemispheres and pointed out its attitude to white substance fibers. However, in the interpretation of brain functions, he fell entirely from the positions of the modern "psychology of abilities." It was he who became the author of the concept, according to which each mental ability relies on a certain group of cerebral cells and the entire brain bark (which he first began to consider as the most important part of the large hemispheres involved in the implementation of mental functions) represents a combination of individual "bodies", each of which is a substrate of a certain mental "ability".
Those "abilities" that Gall directly timed to the individual sections of the cerebral cortex, were, as already mentioned, in the finished form they were taken from the modern psychology to him. Therefore, along with such relatively simple functions, as visual or hearing memory, orientation in space or a sense of time, in a set of "abilities", localized in certain sections of the cortex, appeared "instincts of the order", "love for parents", "sociability" , "Courage", "ambition", "fuel to upbringing", etc.
On the one hand, the consideration of the cerebral cortex as a system, different in its functions proposed by Galle, in such a fantastic donatic form, was to a certain extent progressive, since it was a thought about the possibility of a differentiated approach to the apparent homogeneous mass of the brain. On the other hand, the ideas of "brain centers" formulated by Gall, in which complex mental functions are localized, in their original principal positions were so strong that they were preserved in the form of psychomorphological representations of "narrow localizationism" and in a later period, when the study of the brain organization of mental processes Received a more real scientific basis. These ideas determined the approach to the problem of localization of functions in the cortex of the brain hardly during the whole century.
Back in the second half of the XVIII century. Gall (1769), not denying the fact that various parts of the brain may relate to different functions, suggested that the brain is a single body that transforms impressions into mental processes and that it should be considered as "SENSORIUM. sotht-Ipe ", parts of which are equivalent. Proof of this provision he saw in the fact that one focus can cause a violation of different "abilities" and that defects caused by this hearth may be subject to a certain extent.
In April 1861, Brock demonstrated the brain of his first patient in the Paris anthropological society, whose violation of articulated speech was observed. At the opening, the patient was found the defeat of the rear third of the lower headquarters of the left hemisphere. In November of the same year, he repeated a similar demonstration, the brain of the second such patient. This gave him the opportunity to express the assumption that the articulated speech is localized in a clearly limited section of the brain, and that the region specified by them can be considered as the "Center of Motor Image Images". Based on these observations, Brock made a bold conclusion, fundamentally continued attempts to directly coincide with
psychological functions to limited parts of the brain, namely, that the cells of this brain cord area are a kind of "depot" of the images of those movements that "make up our articulated speech. Brock finished its report by a pathetically sounding position:" From the moment that the intellectual function is associated with a limited area of \u200b\u200bthe brain, the provision that intelligent functions relate to the whole brain will be rejected and will be highly likely that each convolution has its own private functions. "
Brock's find was a push for the appearance of a number of clinical studies, which not only multiplied the facts found by them, but also enriched the position of "local polishes" a whole series of new observations. After a decade after Brock's find, Vernika (1874) described the case when the defeat of the back third of the upper temporal winding of the left hemisphere caused a violation of the understanding of speech. The conclusion of the Wernik that "Sensor-like images" are localized in the zone of the left hemisphere described by him, then firmly entered the literature.
For two decades, such "centers" such as "centers of visual memory" (Bastian, 1869), "Centers" (Exner, 1881), "Centers", or "Centers", or "Ideaz Centers" were described (Broadbent, 1872, 1879; Charco, 1887; Grass, 1907) with their connections. Therefore, a very soon map of the cerebral cortex of a person was filled with numerous schemes, which were projected on the brain substrate of the representation of associative psychology dominated at the time.
1 It should be noted that the works of Jackson, for which by the plant again drew attention to A. P and K (1913), gHead (1926) and O.Feruster (1936), were first published in consolidated form only in 1932 (in England), and then in 1958 (in the USA).
Back in the 60s of the last century, the wonderful English neurologist Houulings Jackson, who first described local epileptic seizures, formulated a number of provisions, cut - - to those contrary to the modern ideas of narrow "localizationism". These provisions were destined to play a significant role in the further development of neurological thought, were presented to them in his discussion from Brock shortly after the publication of the observations of the latter. However, over the next decades, they were moved to the rear plan for the successes of "narrow-calling" views. Only in the first quarter of the twentieth century, these ideas were widely recognized. Facts from which Jackson proceeded, really entered the conflict with the main representations of Brock and abruptly contradicted the concepts of cell localization of functions. Studying disorders and speech at focal brain lesions, Jackson noted the paradoxical at first glance, the phenomenon concluded in the fact that the defeat of a certain limited portion of the brain never leads to the complete loss of the function. The patient with a focal lesion of a certain zone of the cortex often cannot arbitrarily perform the required movement or arbitrarily repeat the specified word, but it turns out to be able to do it involuntarily, i.e. Reproducing the same movement or pronouncing the same word in a state of affect or in the usual statement.
Based on such facts, Jackson built the overall concept of the neurological organization of functions, sharply different from classical representations. In his opinion, each function carried out by the central nervous systemis not the departure of the narrow-line cell group that make up the "depot" for this function. The function has a complex "vertical" organization: presented for the first time on the "lower" (special or stem) level, it is a second time. (RE-REPRESENTED) on the "average" level of motor (or sensory) departments of the cerebral cortex and for the third time (RE-RE-REPRESENTED) - "Higher" level, what Jackson considered the level of the frontal brain departments. Therefore, according to Jackson, localization symptom (loss of a particular function), which accompanied the defeat of a limited section of the central nervous system, cannot be identified with localization of the function. The latter can be placed in the central nervous system much more difficult and have a completely different brain organization.
Jackson's ideas were wrong, one-way appreciated by his contemporaries. Regulations on the complex nature and "vertical" organization of functions, for many decades, anticipating the development of science and received its confirmation only these days remained forgotten for a long time. On the contrary, his statements directed against a narrow localization of functions in limited areas of the cerebral cortex, and its instructions for the complex "intellectual" or "arbitrary" nature of the highest psychological processes were picked up by the most idealistic part of researchers who saw in these provisions in the struggle Against materialistic sensualism of classics neurology. Since the 70s, researchers appeared from the 70s,
who tried to see the creature of mental processes in complex "symbolic" functions. These researchers opposed their views by the ideas of narrow localizationism; They considered the foundation mental processes The activities of the whole brain as a whole or at all refused to talk about their material substrate and were limited to an indication that a person's mental life is a new, "disturbed" type of activity, which is carried out by the brain as an "instrument of spirit."
The researchers of this group include Finnburg (1870), which, as opposed to Brock and Vernik, was interpreted by a complex "symbolic" function.
A close position was also served by Kussmauul (1885), who denied the views, according to which the material basis of memory are special "depot" in the cerebral cortex, where the images and concepts are "sorted in separate regiments". Considering the "symbolic function" the main for mental life and believing that every complex brain impairment leads to Asimbolia, he wrote: "With a smile, we turn away from all naive attempts to find a speech in a particular brain urge."
If at the end of the XIX century. The voices of researchers who called on to reject the sensualist approach to brain activity and stand in position difficult to localize "symbolic function" remained only single, then by the beginning of the 20th century. Under the influence of the revival of idealistic philosophy and psychology, they began to strengthen and soon turned into a leading direction in the analysis of higher mental processes.
It is by this time that Bergson's speeches (1896), who tried to substantiate a bright idealistic approach to the psyche, considering active dynamic schemes as the main moving force Spirit and opposing their material "brain memory." The very beginning of the century includes psychological studies of the Würzburg school, which put forward that the abstract thinking is a primary independent process that does not provide sensory images and speeches, and called back to Platonism.
These ideas penetrated into neurology. They performed at the first plan in the works of the so-called "non -etic" school of neurologists and psychologists (P. Marie, 1906 and especially Van Verkop, 1925; Bowman and Greutbaum, 1825, and then Goldstein, 1934, 1942, 1948). Representatives of this school defended the situation according to which the main type of mental processes
it is "symbolic activity", implemented in "distracted" schemes, and that each brain disease is manifested not so much in the loss of private processes, but in reducing this "symbolic function" or "abstract installation".
Such statements were radically changed those tasks that were put in front of neurologists in the previous period of science development. Instead of analyzing the material substrate of individual functions on the foreground, the task of describing those forms of reducing the "symbolic function" or "abstract behavior", which arose with any brain lesion appeared. The study of the brain mechanisms of these violations was almost returned to the background. Returning again to the provision that the brain works as a whole, and putting a violation of higher mental processes in relation to primarily with the massiveness of the defeat, and not with its topics, these authors have enriched a psychological analysis of changes in loosening activities at local brain lesions; However, they created a significant obstacle to the materialistic studies of the brain mechanisms of mental processes.
Attempts to translate neurology in the direction of the idealistic interpretation of mental disorders met, however, noticeable difficulties. The situation of such major neurologists, as Monasks (1914, 1928), Head (1926), and above all, Goldstein (1934, 1942, 1948) were particularly difficult (1934, 1942, 1948), which partially or fully joined the "new" direction and had to combine the previous well-established in neurology "Lacalizer" views with new, "anti-localization". Each of these neurologists came out of this difficulty in its own way. Monkkov, remaining the largest prestige in the study of the brain structures underlying elementary neurological symptoms, practically refused to apply the same principle to decipher the brain basis of violations of "symbological activities", which he called "Asemia". In his publication, together with Mur-Gom (1928), he came to the openly ideal explanation of these violations by changes in the depths of "instincts". Head, who firmly entered into neurology with its sensitivity studies, limited his attempts to study complex speech disorders with a description of the violation of individual sides of the speech act, very conventionally comparing them with lesions of large brain bark zones. Without giving these facts any neurological explanation, he turned to a general factor
wakeful ("Vigilance") as a final explanatory principle.
The most instructive turned out to be, however, the position of Goldsh Tayne is one of the largest neurologists of our time. Adhering to classic views in relation to elementary neurological processes, he joined new, "but-ethical" ideas for complex human mental processes, highlighting as their distinctive features "abstract installation" and "categorical behavior".
Goldstein believed that the violation of this "abstract installation" or "categorical behavior" occurs with every brain defeat. This statement made him take a very peculiar position in explaining both processes described by him - violations of elementary and higher mental functions. Trying to understand the brain mechanisms of these processes, Goldstein allocated the "periphery" of the bark, which allegedly retains the localization principle of its structure, and the "central part" of the cortex, which, unlike the first, is "equipotential" and works on the principle of creating "dynamic structures" arising on Famous "dynamic background". The defeat of the "periphery of the crust" lead to a violation of "means" of mental activity ("Werkzengstdr-Ung"), but leave the saved "abstract installation". The defeat of the "central part" of the crust leads to a deep change in the "abstract installation" and "categorical behavior", subject to the "law of mass": the greater mass of the brainstanty covers this defeat, the more the formation of complex "dynamic structures" and the more differentiated "dynamic structures" The relations of "structures" and "background", which, according to Goldstein, are the neurological basis of this complex "categorical behavior". Becoming the position of "gelty-studentpsychology" and naturalistically understanding the complex forms of human behavior, Goldstein actually repeated the misleading Leshli, who tried to appeal to explain the most complex forms of intellectual activity to elementary ideas about the diffuse and equipotential mass of the brain. In other words, Goldstein practically combined the classic positions of narrow "localizationism" and new "antilocalysts" ideas.
Luria A. R. Higher Corner Functions of Human. - M. 1962.
A. R. Luria
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