Трифонов Е.В.
Антропология:   дух - душа - тело - среда человека,

или  Пневмапсихосоматология человека

Русско-англо-русская энциклопедия, 18-е изд., 2015




Общий предметный алфавитный указатель

Психология Соматология Математика Физика Химия Наука            Общая   лексика

reticular formation ]

(Лат.: reticulum - сетка, formo - имеющий вид)


Схема. Организация ретикулярной формации.
Модификация: Hendelman W. Atlas of Funtional Neuroanatomy, Second Edition, 2006, 15,5 MB. Доступ к данному источнику = Access to the reference.

p.29 FIGURE 42A RETICULAR FORMATION 1 RETICULAR FORMATION: ORGANIZATION The reticular formation, RF, is the name for a group of neurons found throughout the brainstem. Using the ventral view of the brainstem, the reticular formation occupies the central portion or core area of the brainstem from midbrain to medulla (see also brainstem cross-sections in Figure 65–Figure 67). This collection of neurons is a phylogenetically old set of neurons that functions like a network or reticulum, from which it derives its name. The RF receives afferents from most of the sensory systems (see next illustration) and projects to virtually all parts of the nervous system. Functionally, it is possible to localize different subgroups within the reticular formation: • Cardiac and respiratory “centers”: Subsets of neurons within the medullary reticular formation and also in the pontine region are responsible for the control of the vital functions of heart rate and respiration. The importance of this knowledge was discussed in reference to the clinical emergency, tonsillar herniation (with Figure 9B). • Motor areas: Both the pontine and medullary nuclei of the reticular formation contribute to motor control via the cortico-reticulo-spinal system (discussed in Section B, Part III, Introduction; also with Figure 49A and Figure 49B). In addition, these nuclei exert a very significant influence on muscle tone, which is very important clinically (discussed with Figure 49B). • Ascending projection system: Fibers from the reticular formation ascend to the thalamus and project to various nonspecific thalamic nuclei. From these nuclei, there is a diffuse distribution of connections to all parts of the cerebral cortex. This whole system is concerned with consciousness and is known as the ascending reticular activating system (ARAS). • Pre-cerebellar nuclei: There are numerous nuclei in the brainstem that are located within the boundaries of the reticular formation that project to the cerebellum. These are not always included in discussions of the reticular formation. It is also possible to describe the reticular formation topographically. The neurons appear to be arranged in three longitudinal sets; these are shown in the left-hand side of this illustration: • The lateral group consists of neurons that are small in size. These are the neurons that receive the various inputs to the reticular formation, including those from the anterolateral system (pain and temperature, see Figure 34), the trigeminal pathway (see Figure 35), as well as auditory and visual input. • The next group is the medial group. These neurons are larger in size and project their axons upward and downward. The ascending projection from the midbrain area is particularly involved with the consciousness system. Nuclei within this group, notably the nucleus gigantocellularis of the medulla, and the pontine reticular nuclei, caudal (lower) and oral (upper) portions, give origin to the two reticulo-spinal tracts (discussed with the next illustration, also Figure 49A and Figure 49B). • Another set of neurons occupy the midline region of the brainstem, the raphe nuclei, which use the catecholamine serotonin for neurotransmission. The best-known nucleus of this group is the nucleus raphe magnus, which plays an important role in the descending pain modulation system (to be discussed with Figure 43). In addition, both the locus ceruleus (shown in the upper pons) and the periaqueductal gray (located in the midbrain, see next illustration and also Figure 65 and Figure 65A) are considered part of the reticular formation (discussed with the next illustration). In summary, the reticular formation is connected with almost all parts of the CNS. Although it has a generalized influence within the CNS, it also contains subsystems that are directly involved in specific functions. The most clinically significant aspects are: • Cardiac and respiratory centers in the medulla • Descending systems in the pons and medulla that participate in motor control and influence muscle tone • Ascending pathways in the upper pons and midbrain that contribute to the consciousness system

Схема. Ядра ретикулярной формации.
Модификация: Hendelman W. Atlas of Funtional Neuroanatomy, Second Edition, 2006, 15,5 MB. Доступ к данному источнику = Access to the reference.

p 31
RETICULAR FORMATION: NUCLEI In this diagram, the reticular formation is being viewed from the dorsal (posterior) perspective (see Figure 10 and Figure 40). Various nuclei of the reticular formation, RF, which have a significant (known) functional role, are depicted, as well as the descending tracts emanating from some of these nuclei. Functionally, there are afferent and efferent nuclei in the reticular formation and groups of neurons that are distinct because of the catecholamine neurotransmitter used, either serotonin or noradrenaline. The afferent and efferent nuclei of the RF include: • Neurons that receive the various inputs to the RF are found in the lateral group (as discussed with the previous illustration). In this diagram, these neurons are shown receiving collaterals (or terminal branches) from the ascending anterolateral system, carrying pain and temperature (see Figure 34; also Figure 35). • The neurons of the medial group are larger in size, and these are the output neurons of the reticular formation, at various levels. These cells project their axons upward or downward. The nucleus gigantocellularis of the medulla, and the pontine reticular nuclei, caudal, and oral portions, give rise to the descending tracts that emanate from these nuclei — the medial and lateral reticulo-spinal pathways, part of the indirect voluntary and nonvoluntary motor system (see Figure 49A and Figure 49B). • Raphe nuclei use the neurotransmitter serotonin and project to all parts of the CNS. Recent studies indicate that serotonin plays a significant role in emotional equilibrium, as well as in the regulation of sleep. One special nucleus of this group, the nucleus raphe magnus, located in the upper part of the medulla, plays a special role in the descending pain modulation pathway (described with the next illustration). There are other nuclei in the brainstem that appear to functionally belong to the reticular formation yet are not located within the core region. These include the periaqueductal gray and the locus ceruleus. The periaqueductal gray of the midbrain (for its location see Figure 65 and Figure 65A) includes neurons that are found around the aqueduct of the midbrain (see also Figure 20B). This area also receives input (illustrated but not labeled in this diagram) from the ascending sensory systems conveying pain and temperature, the anterolateral pathway; the same occurs with the trigeminal system. This area is part of a descending pathway to the spinal cord, which is concerned with pain modulation (as shown in the next illustration). The locus ceruleus is a small nucleus in the upper pontine region (see Figure 66 and Figure 66A). In some species (including humans), the neurons of this nucleus accumulate a pigment that can be seen when the brain is sectioned (prior to histological processing, see photograph of the pons, Figure 66). Output from this small nucleus is distributed widely throughout the brain to virtually every part of the CNS, including all cortical areas, subcortical structures, the brainstem and cerebellum, and the spinal cord. The neurotransmitter that is used by these neurons is noradrenaline and its electrophysiological effects at various synapses are still not clearly known. Although the functional role of this nucleus is still not completely understood, the locus ceruleus has been thought to act like an “alarm system” in the brain. It has been implicated in a wide variety of CNS activities, such as mood, the reaction to stress, and various autonomic activities. The cerebral cortex sends fibers to the RF nuclei, including the periaqueductal gray, forming part of the cortico-bulbar system of fibers (see Figure 46). The nuclei that receive this input and then give off the pathways to the spinal cord form part of an indirect voluntary motor system — the cortico-reticulo-spinal pathways (discussed in Section B, Part III, Introduction; see Figure 49A and Figure 49B). In addition, this system is known to play an extremely important role in the control of muscle tone (discussed with Figure 49B). CLINICAL ASPECT Lesions of the cortical input to the reticular formation in particular have a very significant impact on muscle tone. In humans, the end result is a state of increased muscle tone, called spasticity, accompanied by hyper-reflexia, an increase in the responsiveness of the deep tendon reflexes (discussed with Figure 49B). © 2006

Схема. Ретикулярная формация. Система модуляции боли.
Модификация: Hendelman W. Atlas of Funtional Neuroanatomy, Second Edition, 2006, 15,5 MB. Доступ к данному источнику = Access to the reference.

FIGURE 43 RETICULAR FORMATION 3 PAIN MODULATION SYSTEM Pain, both physical and psychic, is recognized by the nervous system at multiple levels. Localization of pain, knowing which parts of the limbs and body wall are involved, requires the cortex of the postcentral gyrus (SI); SII is also likely involved in the perception of pain (discussed with Figure 36). There is good evidence that some “conscious” perception of pain occurs at the thalamic level. We have a built-in system for dampening the influences of pain from the spinal cord level — the descending pain modulation pathway. This system apparently functions in the following way: The neurons of the periaqueductal gray can be activated in a number of ways. It is known that many ascending fibers from the anterolateral system and trigeminal system activate neurons in this area (only the anterolateral fibers are being shown in this illustration), either as collaterals or direct endings of these fibers in the midbrain. This area is also known to be rich in opiate receptors, and it seems that neurons of this region can be activated by circulating endorphins. Experimentally, one can activate these neurons by direct stimulation or by a local injection of morphine. In addition, descending cortical fibers (cortico-bulbar) may activate these neurons (see Figure 46). The axons of some of the neurons of the periaqueductal gray descend and terminate in one of the serotonincontaining raphe nuclei in the upper medulla, the nucleus raphe magnus. From here, there is a descending, crossed, pathway, which is located in the dorsolateral white matter (funiculus) of the spinal cord. The serotonergic fibers terminate in the substantia gelatinosa of the spinal cord, a nuclear area of the dorsal horn of the spinal cord where the pain afferents synapse (see Figure 32). The descending serotonergic fibers are thought to terminate on small interneurons, which contain enkephalin. There is evidence that these enkephalin-containing spinal neurons inhibit the transmission of the pain afferents entering the spinal cord from peripheral pain receptors. Thus, descending influences are thought to modulate a local circuit. There is a proposed mechanism that these same interneurons in the spinal cord can be activated by stimulation of other sensory afferents, particularly those from the touch receptors in the skin and the mechanoreceptors in the joints; these give rise to anatomically large well-myelinated peripheral nerve fibers, which send collaterals to the dorsal horn (see Figure 32). This is the physiological basis for the gate theory of pain. In this model, the same circuit is activated at a segmental level. It is useful to think about multiple gates for pain transmission. We know that mental states and cognitive processes can affect, positively and negatively, the experience of pain and our reaction to pain. The role of the limbic system and the “emotional reaction” to pain will be discussed in Section D. CLINICAL ASPECT In our daily experience with local pain, such as a bump or small cut, the common response is to vigorously rub and/or shake the limb or the affected region. What we may be doing is activating the local segmental circuits via the touch- and mechano-receptors to decrease the pain sensation. Some of the current treatments for pain are based upon the structures and neurotransmitters being discussed here. The gate theory underlies the use of transcutaneous stimulation, one of the current therapies offered for the relief of pain. More controversial and certainly less certain is the postulated mechanism(s) for the use of acupuncture in the treatment of pain. Most discussions concerning pain refer to ACUTE pain, or short-term pain caused by an injury or dental procedure. CHRONIC pain should be regarded from a somewhat different perspective. Living with pain on a daily basis, caused, for example, by arthritis, cancer, or diabetic neuropathy, is an unfortunately tragic state of being for many people. Those involved with pain therapy and research on pain have proposed that the CNS actually rewires itself in reaction to chronic pain and may in fact become more sensitized to pain the longer the pain pathways remain active; some of this may occur at the receptor level. Many of these people are now being referred to “pain clinics,” where a team of physicians and other health professionals (e.g., anesthetists, neurologists, psychologists) try to assist people, using a variety of therapies, to alleviate their disabling condition.

См.: Неврология: Словарь,
         Неврология: Ресурсы Интернет,


В отдельном окне: 

«Я    У Ч Е Н Ы Й    И Л И . . .    Н Е Д О У Ч К А ?»
    Т Е С Т    В А Ш Е Г О    И Н Т Е Л Л Е К Т А

Эффективность развития любой отрасли знаний определяется степенью соответствия методологии познания - познаваемой сущности.
Живые структуры от биохимического и субклеточного уровня, до целого организма являются вероятностными структурами. Функции вероятностных структур являются вероятностными функциями.
Необходимое условие:
Эффективное исследование вероятностных структур и функций должно основываться на вероятностной методологии (Трифонов Е.В., 1978,..., ..., 2015, …).
Критерий: Степень развития морфологии, физиологии, психологии человека и медицины, объём индивидуальных и социальных знаний в этих областях определяется степенью использования вероятностной методологии.
Актуальные знания: В соответствии с предпосылкой, реальностью, необходимым условием и критерием... ...
о ц е н и т е   с а м о с т о я т е л ь н о:
—  с т е п е н ь  р а з в и т и я   с о в р е м е н н о й   н а у к и,
—  о б ъ е м   В а ш и х   з н а н и й   и
—  В а ш   и н т е л л е к т !

Любые реальности, как физические, так и психические, являются по своей сущности вероятностными.  Формулирование этого фундаментального положения – одно из главных достижений науки 20-го века.  Инструментом эффективного познания вероятностных сущностей и явлений служит вероятностная методология (Трифонов Е.В., 1978,..., ..., 2014, …).  Использование вероятностной методологии позволило открыть и сформулировать важнейший для психофизиологии принцип: генеральной стратегией управления всеми психофизическими структурами и функциями является прогнозирование (Трифонов Е.В., 1978,..., ..., 2012, …).  Непризнание этих фактов по незнанию – заблуждение и признак научной некомпетентности.  Сознательное отвержение или замалчивание этих фактов – признак недобросовестности и откровенная ложь.

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