EXTRAPYRAMIDAL SYSTEM

From Big Medical Encyclopedia
Revision as of 22:52, 1 January 2017 by Doctordss (talk)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

EXTRAPYRAMIDAL SYSTEM (systema extrapyramidale) — the system of kernels of a brain and motive extra pyramidal (extrapyramidal) conduction paths which is carrying out involuntary, automatic regulation and coordination of difficult motive acts, regulation of a muscle tone, maintenance of a pose, the organization of motive manifestations of emotions.

AA. page unlike pyramidal system (see) is not strictly outlined anatomic and functional system. It combines nek-ry departments cerebral cortex (see), basal kernels (see), nuclear formations of a brain trunk (see. Brain ), cerebellum (see), segmented device spinal cord (see), and also the extensive communications which are carrying out instant functional integration of many neyronalny systems providing the complex organization of motive and behavioural acts.

The anatomy

Extrapyramidal system includes a striate body (corpus striatum) consisting of a kernel (nucleus caudatus) having a tail and a lenticular kernel (nucleus lenticularis), medial kernels of a thalamus (nuclei mediales thalami), a subthalamic kernel (nucleus subthalamicus, s. corpus Luysi), kernels of a hypothalamus (nuclei hypothalamici), black substance (substantia nigra), a red kernel (nucleus ruber), kernels of a reticular formation (nuclei formationis reticularis), an olive (oliva) of a myelencephalon. The kernel having a tail consists of a head (caput), a body (corpus) and a tail (cauda); a lenticular kernel — from a shell (putamen), a pale sphere (globus pallidus), medial and lateral brain plates (laminae medullares medialis et lateralis). Also motive extrapyramidal conduction paths enter extrapyramidal system: the cortical ways originating from the neurons of the cortical motive field 4 and neurons located in somatosensory cortical fields, connecting bark of cerebral hemispheres with formations of extrapyramidal system; the striopallidal ways connecting educations E. page among themselves; the trunkospipalny ways going from the listed motive kernels of a brain to motive kernels of a spinal cord and cranial nerves. Carry to extrapyramidal system also a cerebellum.

AA. the page represents phylogenetic old system. The end brain of the lowest vertebrata has no bark, and the cellular accumulations forming basal kernels lie in its depth. AA. the page of the lowest vertebrata is the highest department accepting signals from organ receptors and sending impulses to muscles through the centers of a spinal cord. At fishes from educations E. the page is available only a pale sphere of a lenticular kernel, amphibians have a shell of this kernel. At reptiles and birds with the developed cerebral cortex new basal kernels are formed (e.g., a kernel having a tail), but the indirect descending ways from these kernels remain. At the same time the feedforward between a cerebral cortex and a spinal cord at them is absent. Only mammals in addition to extra pyramidal have also direct descending pyramidal motive ways from a cerebral cortex to motoriums of a spinal cord.

On the basis of the basal kernels given about development in E. pages allocate its nuclear part — striopallidal system, at the same time combine a kernel having a tail and a shell of a lenticular kernel under the name «striatum» (striatum), or «neostriatum», and designate a pale sphere as a pallidum (pallidum). Carry also black substance and a red kernel to system of a pallidum (see. Mesencephalon ). A striatum — phylogenetic younger education, than a pallidum. Formations of striopallidal system are connected among themselves by striopallidal conduction paths (see. Motoriums, ways ).

Physiology

the Main fiziol. functions E. pages provide coordination of motive acts of the person and animals, regulation of a muscle tone and maintenance of a pose, the organization of motive manifestations of emotions. Complexity of a structure of extrapyramidal system, extensiveness of bonds of its structures with various formations of a brain do difficult understanding of physiological mechanisms of extrapyramidal regulation of motive acts. Unlike pyramidal system (see) extrapyramidal system the pas separate ways is not divided, and represents a complex system of motive kernels and bonds between them, and also bonds of motoriums of various function levels of a brain with efferent neurons of a spinal cord (see) and kernels of cranial nerves through numerous subcrustal and trunk structures. In a spinal cord the impulses arriving on the descending pyramidal path and fibers E.s., interact with the vozbuzhdeniye coming on afferent ways from proproiretseptor. Process of integration of vozbuzhdeniye at the level of a spinal cord is an important link in the mechanism not only any, but also involuntary. Beginning E. pages give preferential axons of neurons of the cortical motive field 4, and also the neurons located in somatosensory bark. At the same time many fibers E. pages begin also in other touch areas of bark (acoustical, visual and flavoring) and in associative zones frontal, parietal and temporal shares of a brain (see. Cerebral cortex ). From cells of a cerebral cortex impulses on ekstraliramidny ways go to neurons thalamus (see), hypothalamus (see), bridge of a brain (see), red kernels, black substance and reticular formation (see). From the field the 4th extrapyramidal fibers together with fibers of a pyramidal path go as a part of the internal capsule to the most ancient groups of motive kernels — to basal kernels (see). These kernels take the central place among structures E. page, being the highest nadsegmentarny device providing regulation of motive acts with participation of various muscular groups. By means of basal kernels all synergies which are a part of such difficult motive acts as walking, run, a lasagna, etc. are carried out. With the participation of E. the page is created smoothness of movements and the initial pose for their performance is established. Pilot studies and clinical observations allow to note variety of forms and at the same time unambiguity (strengthening or suppression) of motor reactions at destruction or irritation of extrapyramidal educations. Damages of educations E. pages cause various disturbances in the motive sphere. So, at damage of the internal capsule in the depth of a cerebral hemisphere where there pass both pyramidal, and extrapyramidal fibers, spastic increase in a tone of muscles of the paralyzed extremities is observed (see. Hemiplegia ), a cut it is caused by destruction of extrapyramidal conductors exerting normal brake impact on a reticular formation. Usually at the isolated damage of a pyramidal path at the level myelencephalon (see) where the majority of extrapyramidal fibers goes separately and is not mentioned at damage, the hypomyotonia is observed. The most expressed brake effects are shown in eksper the cop at stimulation of extrapyramidal areas of a cerebral cortex. As showed the Tower (S. S. Tower, 1940), cortical braking can be two types — braking muscular tone (see) and braking of made movements (see). The last type of braking is characteristic of the descending cortical extrapyramidal influences, they play an important role in regulation fiziol. activities of motive extrapyramidal kernels of a brain trunk, from to-rykh to motoriums of a spinal cord the powerful flow of vozbuzhdeniye arrives. Direct pyramidal cortical bonds accelerate the movements and provide a possibility of their thinner differentiation. The extrapyramidal movements caused by stimulation of various sites of bark are slower and stereotypic. For lack of brake influences of a cerebral cortex of the movement turn in a row convulsive muscular contractions.

Among textural features E. the page a striatum is considered the highest subcrustal regulatory and coordination center of the organization of movements while the pallidum, influencing neurons of a spinal cord through structures of an average and myelencephalon, coordinates a tone and a phase physical activity of muscles. Activity of striopallidal structures is connected with performance of slow difficult movements, such as slow walking, step through an obstacle, threading of a thread in a needle, etc. At implementation of any movement in limited or in excessive volume afferent the return lower from proprioceptors signals about it, and from basal kernels to motive areas of a cerebral cortex and to trunk structures signals of correction arrive. Thus, pyramidal and extrapyramidal systems manage to make on the course of performance of movements corrections to a continuous stream of motive vozbuzhdeniye. After destruction of a striatum there are involuntary chaotic movements of separate extremities — hyperkinesias (see). Disturbances of extrapyramidal regulation of any and involuntary physical activity of mimic muscles (see. Mimicry ) lead to inadequate external expression emotions (see), to involuntary laughter and crying or total absence of mimic expression (mask-like face).

One of functions of a pale sphere is braking of underlying kernels of a mesencephalon. At damage of a pale sphere increase in a tone of skeletal muscles (hyper tone) owing to release of a red kernel of a mesencephalon from the braking influence of a pallidum is observed. The irritation of a pale sphere leads to increase in a tone of muscles and a tremor of extremities, and also to restriction and constraint of movements. These phenomena are eliminated at destruction of a pallidum. Braking of movements is observed also at irritation of a striate body. Similar effects of suppression of movements are noted at irritation of so-called brake zones of extra pyramidal system (a zone cerebral cortex, parts of motor bark, a kernel having a tail, a cerebellum, a reticular formation).

The striatum gives rise to many motive ways E. pages, among to-rykh allocate the effector way going to a pallidum, and further through a red kernel and a rubrospinalny path — to a spinal cord. The striatum including a kernel having a tail and a shell of a lenticular kernel rather well morphologically and neurophysiological is studied. The abundance of intercommunications is feature of its structure though the small number of neurons sends the axons and to other structures of a brain, including to kernels of a thalamus and a hypothalamus. Pilot physiological studies using microelectrodes showed (see. Microelectrode method of a research ), that the striatum exerts dual impact on neurons of a pale sphere — exciting and braking. The electric irritation of a kernel having a tail, a shell and a pale sphere causes braking of a motive component of conditional and unconditional reactions of animals. Assume that morphological substrate of similar brake influences are the direct ascending bonds of the listed structures with motor and somatosensory bark, and also with thalamic kernels (ventral front and lateral) and the median center.

The head of a kernel having a tail plays an important role in the organization of prestarting processes, to-rye include reorganization poses (see), preceding arbitrary motive act. It is confirmed by data of the microelectrode researches which revealed changes of neyronalny activity of a head of a kernel having a tail during the period preceding implementation of autokinesia. So, by means of microelectrode methods Nicknames (H. Niki with sotr. (1972) showed that at monkeys in a situation of the simple choice and pressing the lever activation of neurons of a head of a kernel having a tail before autokinesia precedes activation of neurons of prefrontal cortex. Elektromiografichesky activity of an extremity of an animal is registered on average in 110 ms after activation of a head of a kernel having a tail. According to Evarts (E.V. Evarts, 1966), the category of pyramidal neuron in a cerebral cortex of a monkey precedes muscular activity of her extremity on 50 — 100 ms.

Most structures E. the page has no true output to motor-neurons of a spinal cord, their influence on them is mediated through the reticulospinal path which is as if the general final way of extrapyramidal system (see. Motoriums, ways ). Besides, extrapyramidal influences on a spinal cord and kernels of cranial nerves are carried out in the trunkospinalny ways which are carrying out impulses from kernels diencephalon (see), mesencephalon (see) and a myelencephalon (see). These ways include rubrospinalny, vestibulospinalny and olivispinal ways. In the same ways a part of cerebellar influences on motor-neurons of a spinal cord is carried out (see. Cerebellum ). The community of effects of these influences with extrapyramidal regulation allows to carry these structures to extrapyramidal system.

All supraspinal structures entering in E. pages, address the influences to gamma motor-neurons of a spinal cord (see). As showed researches P. Granite, gamma motor-neurons regulate a flow of the proprioceptive afferent impulses coming to a spinal cord from muscle spindles (see. Proprioceptors ). These afferent impulses influence excitability of alpha motor-neurons, activity to-rykh defines the working condition of skeletal muscles. For example, inclusion of motor-neurons in myotatic contraction — a myostatic reflex — represents often spinal process for which ensuring there is enough inclusion of one-two spinal segments. In this process direct control of motor-neurons by means of the signals arriving from primary proprioreptor takes place. The descending influences from structures E. pages can facilitate or suppress myotatic contraction that is shown at not tserebratsionny rigidity (see) when myostatic reflexes (extremely amplify see. Reflex ). The factor strengthening them is increase under the influence of the descending influences of activity of gamma motor-neurons, edges are led, in turn, to increase of categories of stretch receptors and the corresponding intensification of monosynaptic activation of alpha motor-neurons. At the same time the fast-carrying-out fibers originating from a medial part of a reticular formation of a myelencephalon and a varoliyev of the bridge (see. Bridge of a brain ), and also from a lateral vestibular nucleus of Deyters (see. Eighth cranial nerve ) too monosinaptichesk excite alpha motor-neurons of a spinal cord and provide implementation of bystry movements. The Medlennoprovodyashchy descending way of a tire of a mesencephalon provides regulation of tonic reactions. Thus, if the descending influences of pyramidal system (see), affecting directly alpha motor-neurons, increase their functional activity at implementation of phase and tonic motor reactions of an organism, then the regulating influences E. pages on gamma motor-neurons provide necessary correction of the carried-out movements and are the additional mechanism of impact on a postural and tonic and physical activity. It is most expressed at preservation of vertical position of a body when gravity is counteracted by the reduction of extensor muscles caused by the facilitating influences of trunk structures E. page. The brake regulating influences going from motoriums of bark and striopallidal structures adjust rate of strain of skeletal muscles.

In a crust. time of idea of functions of striopallidal structures significantly extended. Data of a large number of pilot and clinical trials confirm participation of a kernel having a tail, shells, a pale sphere not only in regulation of motor activity, but also in the analysis of afferent flows, in regulation of a number of vegetative functions, in implementation of irregular shapes of an innate behavior, in mechanisms of a short-term memory, and also in regulation of a cycle wakefulness — a dream. Broad participation of striopallidal educations in the organization of difficult behavior of organisms is based on extensive multitouch and heterogeneous convergence of vozbuzhdeniye to separate nervous cells. On neurons there is an interaction of the afferent flows arriving practically from all touch structures, from many areas of a cerebral cortex from thalamic, reticular, nigralny, limbic (see. Limbic system ) and other structures of a brain. E.g., with a low frequency of a background impulsation and a small amount of spontaneously active neurons of a kernel having a tail nearly a half of its cells nevertheless has big convergent capacity and reacts to sound, food and electroskin irritants. To interaction of neurons of structures E. the page and their specific inclusion in implementation of the highest functions are promoted by neurotransmitters — dopamine, serotonin, acetylcholine, GAMK (see. Piperidic acid ), etc. Similar chemical heterogeneity of synoptic educations in structures E. the page provides specialization of inclusion of its components in mechanisms of thin coordination of motive acts. Selective defeat of mediator processes in E. the page causes emergence of characteristic clinical symptomatology in the person.

Thus, broad afferent and efferent bonds of structures E. pages among themselves, bilateral ties of subcrustal kernels with a cerebral cortex, especially with its motor zones, and also specific neuromediator bonds with structures intermediate, an average and a myelencephalon provide broad interaction within E. page that is a basis of the highest integration of behavioural acts and control of them. Functional linkage E. the page with the vegetative centers of a brain causes its inclusion in mechanisms of emotional and affective reactions of an organism.

Pathology

Defeats E. pages are shown by disturbances of the motive sphere, at to-rykh the wedge is not observed. signs of defeat of pyramidal system and disturbances of sensitivity. Pathological extrapyramidal syndromes develop as at defeat of kernels E. page, and its numerous bonds.

Reason of defeat E. pages can be various diseases of a brain — encephalitis (see), vascular diseases (see. Atherosclerosis , Idiopathic hypertensia ), hereditary diseases of c. N of page, craniocereberal injury (see), birth trauma, intoxications manganese, carbon monoxide, tumors or hematomas of a brain of deep localization, etc. Can lead prolonged use of drugs to defeat of structures of extrapyramidal system rauvolfin, Methyldopa, neuroleptics (see), e.g. haloperidol, aminazine, etc., and also heavy allergy (see), asphyxia (see), a polyglobulia (see. Hyperglobulias ), etc.

In a pathogeny of extrapyramidal syndromes as it was established in the last decades, chemical transmitters of nervous impulse are of great importance — mediators (see). At pathology action of specialized mediators — dopamine, acetylcholine, piperidic acid (GAMK), serotonin, etc., the systems of a brain which are contained in corresponding neuro monoaminergicheskikh is broken (dofaminergichesky, cholinergic, Gamkergichesky, serotonergic, etc.). Extrapyramidal patol. syndromes arise at deficit of neuroamines in certain structures E. page, at disturbance of normal balance of the brake and facilitating influences of mediator systems. E.g., motive and emotional manifestations parkinsonism (see) are connected with decrease of the activity of systems of dofaminergichesky neurons of black substance and basal kernels. The neuromediator disturbances which are the cornerstone of a chorea of Gentington (see. Gentington chorea ), are connected with reciprocal interaction of brake GAMK-neurons and dofaminergichesky neurons in a striate body. The hereditary degeneration of neurons of the first type which is observed at this disease promotes release of activity of dofaminergichesky system and emergence of choreic hyperkinesias.

Variety extrapyramidal patol. syndromes it is caused by existence of the so-called anatomo-biochemical dissociation which is expressed that morfol. disturbances at one level E. pages lead by means of the mechanism of slow axonal transport of neuroamines to development of neurochemical disturbances at other level E. page, where morphological patol. changes were absent.

For detection of pathology E. pages determine content catecholamines (see) and other neurotransmitters in blood and cerebrospinal liquid, make an angiography (see), gamma topography (see. Encephalography, radio isotope ), a computer tomography (see. Tomography computer ), an electroencephalography (see), a pneumoencephalography (see), a rheoencephalography (see), investigate a condition of neuromuscular system by means of methods electromyography (see), miotonometriya, stabilografiya, tremorografiya, kimografiya (see. Kimografiya ) hyperkinesias at rest and at stimulation, etc.

At defeats E. pages are broken motive functions, a tone of muscles, a pose of a body, gait, emotional manifestations, vegetovascular reactions. As the person has a close connection between motility and a muscle tone, at pathology of extrapyramidal system the combined disturbances of those and other its functions constantly meet. Defeat of various departments E. the page is followed by development of characteristic clinical syndromes, to-rye conditionally define as hypertensive - hypokinetic, connected preferential with pathology of a pallidum, and hypotonic - hyperkinetic, caused preferential by pathology of a striatum.

Fig. 1. A pose of the patient with parkinsonism with an akinetiko-rigid syndrome: hands are bent in radiocarpal and elbow joints, legs of a polusognuta in knee joints, the head is inclined to a breast.

The symptom complex of defeat of a pallidum and its bonds is characterized hypertensive - the hypokinetic status, the main manifestations to-rogo are increase muscle tone (see) and reduction of a physical activity (hypokinesia) or a practical obezdvizhennost in the absence of paralyzes (akineziya). Extrapyramidal muscular hypertension (pallidarny muscular rigidity) call also wax, or plastic; at the passive movements of extremities of the patient the doctor who is carrying out them tests resistance to the movement, a cut remains identical from beginning to end of the movement. In case of passive extension of the bent extremities of the patient the intermittence, a peculiar gradualness at passive stretching of flexor muscles called a symptom of a cogwheel sometimes is felt. The extrapyramidal hypokinesia is found against the background of safety of force of muscles and a possibility of full volume of movements, the edge, however, is not implemented by the patient since his motive initiative is sharply lowered. At patients with a pallidarny syndrome the general constraint with a characteristic pose is observed: hands are bent in radiocarpal and elbow joints and legs of a polusognuta in knee joints are pressed to a trunk, the head is inclined to a breast (the so-called fleksorny status). The patient, having accepted this or that pose, as if stiffens in this pose, long keeping it (fig. 1). Gait is slowed down, the speech of patients is deaf, monotonous, without normal modulations. The person is deprived of a mimicry, maskoobrazno (see. Mimicry ). All autokinesias are made slowly, hardly (bradykinesia), physiological synkineses (see) are absent, postural reflexes (see) are raised. Pallidarny muscular rigidity in combination with strengthening of postural reflexes and poses, loss of an extrapyramidal kinesis (see. Amyostatic symptom complex ) makes a basis of a syndrome of parkinsonism (see) and atherosclerotic muscular rigidity (an akinetiko-rigid syndrome of Ferster).

One of manifestations of extrapyramidal disturbances is trembling (see), in a pathogeny to-rogo the main role play disturbances in system a red kernel — a reticular formation — a gear kernel of a cerebellum. Trembling (tremor) has the different amplitude of movements, frequency, rhythm and localization (a tremor of fingers, extremities, the heads and dr). Characteristic static trembling of fingers of hands (a tremor of rest) in the form of the rhythmical movement reminding rolling pills or the account of coins is characteristic of Parkinson's disease (see. Trembling paralysis) it is also more often combined with extrapyramidal muscle tension and a gipomimiya. The Statodinamichesky, motor or kinetic trembling (appearing at the movement) is the only symptom of a so-called essential, idiopathic tremor — the independent chronic, slowly progressing disease E. page. The kinetic tremor with the trembling of big amplitude arising in extremities, a trunk, the head in attempt of any purposive movement is observed at hepatocerebral dystrophy (see). The cerebellar type of trembling belongs to dynamic, intentsionny trembling, to-ry it is characteristic for multiple sclerosis (see), nek-ry encephalitis.

At defeat of kernels of a tire of a mesencephalon (see), a reticular formation (see), black substance (see. Mesencephalon ) there are extrapyramidal disturbances in the form of the fixed poses (the fleksorny or ex-tensor status) with strengthening of attitudinal reflexes (see. Postural reflexes ).

The symptom complex of defeat of a striatum and its bonds is characterized by the giperkinetiko-hypotonic status, the main manifestations to-rogo the various involuntary, violent movements, or extrapyramidal hyperkinesias (see), the elaborate poses, grimaces, gesticulations, disturbances of difficult acts of the speech, letter, gait developing against the background of a hypomyotonia or dystonia are.

Fig. 2. Person sick with a chorea of Gentington: the grimace owing to choreic hyperkinesias of face muscles is visible.

The extensive group of striatal disturbances is made by different types of a chorea: a hysterical chorea (see. Rheumatism ), a chorea of Gentington (see. Gentinetona of a trochee ), an atherosclerotic chorea, a chorea of pregnant women, etc. (see. Chorea ). Spasms (see) at a chorea bystry, hyperkinesias wide, appear in all parts of a body, in face muscles. Grimacing (fig. 2) is observed, the speech, the letter falls apart, gait becomes hopping. The tone of muscles is lowered or changeable (dystonia). After acute disorders of cerebral circulation in a striate (striatal) body and the internal capsule there can be a syndrome of a hemochorea, at Krom the choreic hyperkinesia covers only a half of a body. N. K. Bogolepov (1957) described the so-called paroxysmal choreic rubralny hyperkinesia which is shown the cutting, wide movements of all extremities which are followed by rotation of a trunk. Unlike a striatal chorea in this case defeat is localized in upper legs of a cerebellum. Carry to options of a choreic hyperkinesia also a hemiballism (see Hyperkinesias), at Krom broskovy, rotary motions of extremities of one side of a body in combination with hypotonia of muscles are observed. This hyperkinesia arises at defeat of a subthalamic kernel and its bonds with a pale sphere.

Fig. 3. Hand of the patient with an athetosis: a hyperkinesia in distal department with overextension of fingers and a characteristic type of a brush.

One of forms of extrapyramidal hyperkinesias is the athetosis (see). The pathological movements in distal departments of hands, legs, in a face, a neck, observed at an athetosis, are changeable, are not synchronous, are made as if with clearing of obstruction, make an impression of worm-shaped, continuously current spasm (fig. 3).

Fig. 4. A pose of the patient with the torsion spasm: the head is thrown back owing to a spastic muscle tension of a neck.

The muscle tone is changeable (dystonia). The athetotic hyperkinesia is characteristic of cerebral palsy (see. Children's paralyzes), he is also a consequence of encephalitis, vascular and degenerative diseases of a brain. The mixed forms of hyperkinesias are often observed: a choreoathetosis, an athetosis with a so-called thalamic arm (see the Thalamus), etc. The torsion spasm belongs to striatal extrapyramidal hyperkinesias. Widespread are characteristic of it, spasms of the big muscle bulks causing characteristic poses of a body with bending (fig. 4), the overwinding movements of a trunk arising at autokinesias are more often rotary (see. The torsion dystonia). The torsion hyperkinesia in combination with a hemiballism, choreic hyperkinesias, trembling (see above), etc. is observed at hepatocerebral dystrophy (see), leukoencephalites (see) and other defeats of extrapyramidal system.

Toniko-klonichesky hyperkinesias of face muscles of the extrapyramidal nature meet at the front paraspasm (a spasm of Meyzha) covering muscles of an upper part of the face or (at a widespread spasm) all mimic muscles, and also muscles of a neck and extremities. To a paraspasm, as well as many extrapyramidal syndromes, are inherent paradoxical kinezin, i.e. any installations and poses, to the Crimea the patient resorts for reduction or the termination of a hyperkinesia.

At defeat of extrapyramidal system tonic oculogyric crises quite often meet (see. Look paralysis, spasm ), nictitating spasm (see). Spastic belongs to the localized spasms of extrapyramidal genesis wryneck (see), at a cut the neck and the head are violently fixed owing to a spasm of muscles of a neck in various positions (side, front, back). This syndrome appears after encephalitis, intoxications. It is caused by release of cervical and tonic and labyrinth reflexes at the level of oral departments of a brain trunk and can be combined with other extrapyramidal hyperkinesias — trembling, the torsion dystonia. The wryneck caused by defeat E. the page, differs from the reflex wryneck arising in the presence of an additional edge at cervical radiculitis, osteochondrosis (see. Cervicobrachial syndromes ).

At defeat of extrapyramidal system the tic of facial muscles, muscles of an abdominal wall, a diaphragm, a throat can develop (see. Thicke ). The generalized tic in combination with «sudden shouts» at children is known as Turett's syndrome (see. Turetta syndrome ). There is a tic of a diaphragm causing a hiccups and hyperkinesias with the respiratory paroxysms resulting from reduction of muscles of a diaphragm, a front abdominal wall and which are characterized by attacks of the bystry convulsive exhalations which are followed by shouts and a tussiculation. During a paroxysm of such respiratory hyperkinesia pulse becomes frequent, vasculomotor frustration are observed.

Bystry clonic twitchings of separate muscles of a pla of muscular groups, muscular contractions, the covering synergistic muscles, are characteristic of an extrapyramidal myoclonic hyperkinesia. Its development is connected with defeat of rubrodentoolivarny bonds E. page at encephalitis, parasitic, tumoral diseases of a brain, etc. Myoclonias can be observed at a myoclonus epilepsy of Unferrikhta-Lundborga (see the Myoclonus epilepsy), a cerebellar asynergia of Hunt (see. Cerebellum, pathology ). Carry the nizhneolivarny rhythmic myoclonia described by G. Marinesku to extrapyramidal syndromes, at a cut the hyperkinesia is localized by hl. obr. in muscles of a soft palate and an Eustachian tube. The short, bystry spasms of a muscle or its part reminding large fastsikulyation are considered as Fridreykh's paramyoclonus (see. Myoclonia ).

Diagnosis pallidarny syndromes of defeat E. page with characteristic a wedge. manifestations comes easy. At striatal hyperkinetic syndromes it is necessary multilateral a wedge. inspection for confirmation of the organic nature of defeat and differential diagnosis with often observed usual persuasive movements, neurotic tics, reflex spasms of muscles which are not caused by organic lesion E. page.

Treatment extrapyramidal defeats it is directed first of all to a basic disease. Besides, use pathogenetic, symptomatic and fortifying pharmaceuticals. The cholinolytics, muscle relaxants, beta-blockers, means containing L-DOFA, fenotiazina concern to them. In some cases the acupuncture, auto-training are shown. Surgical treatment at pathology E. the page consists in stereotaxic operations (see. Pallidotomiya , Stereotaxic neurosurgery , Talamotomiya ), the separate structures which are carried out for the purpose of destruction E. page, leading to elimination of hyperkinesias and reduction of muscle tension.


Bibliography: Bernstein N. A. Sketches on physiology of movements and physiology of activity, M., 1966; Will wound Ruble. Bases of regulation of movements, the lane with English, M., 1973; Kandel E. I. and Voytyna S. V. The deforming muscular (torsion) dystonia, M., 1971; Konovalov N. V. Hepatocerebral dystrophy, M., 1960; The Multivolume guide to neurology, under the editorship of S. N. Davidenkov, t. 2, page 133, M., 1962, t. 7, page 304, 1960; Neyrotransmitterny systems, under the editorship of N. J. Legga, the lane with English, M., 1982; Petelin L. S. Extrapyramidal hyperkinesias, M., 1970, bibliogr.; Striopallidal system, under the editorship of N. F. Suvorov, L., 1973; Suvorov N. F. Striatal system and behavior, L., 1980; Physiological mechanisms of movements, under the editorship of D. S. Gambaryan, Yerevan, 1978; Private physiology of a nervous system, under the editorship of P. G. Kostiuk, L., 1983; Shapovalov A. I. Neurons and synapses of supraspinal motor systems, L., Aldrige J. W., Anderson R. J. a. Murphy J. T. The role of the basal ganglia in controlling a movement initiated by a visually presented cue, Brain Res., v. 192, p. 3, 1980. H. K. Bogolepov, E. I. Minakova;


S. S. Mikhaylov (An.), Yu. A. Fadeyev (physical.).

Яндекс.Метрика