MINISTRY of HEALTH of UKRAINE Higher State Educational Establishment of Ukraine “Ukranian Medical Stomatological Academy”

MINISTRY OF HEALTH OF UKRAINE Higher State Educational Establishment of Ukraine “Ukranian Medical Stomatological Academy”

"Approved" at the meeting of the Department Human Anatomy on 29.08. 2019. Minutes № 1 Head of Department Professor O. O. Sherstiuk ______

METHODICAL GUIDANCE for students’ self-directed work at practical sessions (when preparing for and during practical sessions)

Academic subject Human Anatomy Module №2 «Splanchnology. Central nervous system and sensory organs» Year of study I Faculty foreign students’ training faculty, specialty «Medicine»

Poltava 2019

Ministry of Health of Ukraine Higher State Educational Establishment of Ukraine “Ukranian Medical Stomatological Academy”

Department of Human Anatomy

Composed by N.L. Svinthythka, Associate Professor at the Department of Human Anatomy, PhD in Medicine, Associate Professor V.H. Hryn, Associate Professor at the Department of Human Anatomy, PhD in Medicine, Associate Professor A.V. Pilugin, Associate Professor at the Department of Human Anatomy, PhD in Medicine, Associate Professor K.A. Lazarieva, Lecturer at the Department of Human Anatomy.

Schedule of classes for students of foreign students’ Training faculty, specialty «Medicine» on module № 2 «Splanchnology. Central nervous system and sensory organs»

№ Topic Instru ction Нours 21 Internal structure of spinal cord. White and grey matters of the 2 spinal cord. 22 Medulla oblongata, pons. 2 23 Cerebellum. The isthmus of the rhombencephalon. 2 24 The fourth ventricle, the rhomboid fossa. 2

25 Midbrain. 2 26 Diencephalon, the third ventricle. 2 27 External structure of cerebral hemispheres. 2 28 The rhinencephalon. Limbic brain. The basal nuclei. 2 29 Structure of grey matter and cortex of cerebral hemispheres. 2 Functional arrangement of the cerebral cortex. 30 The lateral ventricles. The white matter of the cerebral 2 hemispheres. The meninges of the brain. Circulation of cerebrospinal liquid. 31 General esthesiology. Visual analyzer. Eyeball: layers, chambers, 2 refracting medias. 32 Accessory structures of visual analyzer. Nervous pathway of 2 visual analyzer. 33 General characteristic of organ for hearing. External and middle 2 ears. Bones of middle ear, tympanic cavity, its walls.

Topic 21. Internal structure of spinal cord. White and grey matters of the spinal cord. 1. Relevance of the topic: In spinal cord injury complications arise that result in violations of sensitivity, motor activity. Knowledge of the structure of the spinal cord allows the patient to put a true topical diagnosis. 2. The specific aims: Explain the internal structure of the spinal cord. To explain: - Structure of the gray matter of the spinal cord; - The structure of the white matter of the spinal cord; - The nucleus of the spinal cord, their function. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). Biology Knowing the structure of the To be able to distinguish between spinal cord of mammals gray and white matter of the spinal Histology Know the histological structure Tocord be able to distinguish between of gray and white matter gray and white matter of the spinal 4. The tasks for students' individual work. cord 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class. Canalis centralis The central channel Substantia grisea Grey matter Cornu anterius The front horn Cornu laterale Side horns Cornu posterius Rear horns Substantia alba White matter Substantia gelatinosa centralis Central gelatinous substance Columnae griseae Gray column Columna anterior The front pillar Columna posterior The rear pillar

4.2. Theoretical questions for the class:

1. Name the boundaries and show the spinal cord. 2. The name and display the external structure of the spinal cord. 3. What is spinal segment and that their number. 4. How many segments distinguish each of the spinal cord reflex What? 5. What are the components of the reflex arc. 6. What is represented mostly gray and white matter of the spinal cord? 7. What distinguished cord in the spinal cord? 8. What form the gray matter of the spinal cord and which parts of it are distinguished (in operechnomu cut)? 9. What are the core distinction within the gray matter of the spinal cord, and where are they? 10. As built spinal nerve? 11. Due to what formed the anterior and posterior roots of spinal nerves?

4.3. Practical tasks pertaining to the topic and to be completed during the class:The isolated preparation (cut the spinal cord) to be able to show gray, white matter, rear, front spine, spinal ganglion.

The content of the topic: INTERNAL ORGANIZATION In transverse section, the spinal cord is incompletely divided into symmetrical halves by a dorsal (posterior) median septum and a ventral (anterior) median sulcus . It consists of an outer layer of white matter and an inner core of grey matter; their relative sizes and configuration vary according to level. The amount of grey matter reflects the number of neurones present; it is proportionately largest in the cervical and lumbar enlargements, which contain the neurones that innervate the limbs. The absolute amount of white matter is greatest at cervical levels, and decreases progressively at lower levels, because descending tracts shed fibres as they descend and ascending tracts accumulate fibres as they ascend. A diminutive central canal, lined by columnar, ciliated epithelium (ependyma) and containing cerebrospinal fluid (CSF), extends the whole length of the spinal cord lying in the centre of the spinal grey matter. Rostrally, the central canal extends into the caudal half of the medulla oblongata and then opens into the fourth ventricle. SPINAL GREY MATTER In three dimensions, the spinal grey matter is shaped like a fluted column .In transverse section the column is often described as being ‘butterfly-shaped’ or resembling the letter ‘H’ .It consists of four linked cellular masses, the right and left dorsal and ventral horns, that project dorsolaterally and ventrolaterally towards the surface respectively. The grey matter that immediately surrounds the central canal and unites the two sides constitutes the dorsal and ventral grey commissures. The dorsal horn is the site of termination of the primary afferent fibres that enter the cord via the dorsal roots of spinal nerves. The tip of the dorsal horn is separated from the dorsolateral surface of the cord by a thin fasciculus or tract (of Lissauer) in which primary afferent fibres ascend and descend for a short distance before terminating in the subjacent grey matter. The ventral horn contains efferent neurones whose axons leave the spinal cord in ventral nerve roots. A small intermediate, or lateral, horn is present at thoracic and upper lumbar levels; it contains the cell bodies of preganglionic sympathetic neurones. Spinal grey matter is a complex mixture of neuronal cell bodies, their processes and synaptic connections, neuroglia and blood vessels. Neurones in the grey matter are multipolar. They vary in size and features such as the length and the arrangement of their axons and dendrites. Neurones may be intrasegmental, i.e. contained within a single segment, or intersegmental, i.e. their ramifications spread through several segments. Neuronal cell groups of the spinal cord Viewed from the perspective of its longitudinal columnar organization, the grey matter of the spinal cord consists of a series of discontinuous cell groupings associated with their corresponding segmentally arranged spinal nerves. At any particular cross-sectional level these cell groupings are often considered to correspond approximately with one or more of ten cell layers, known as Rexed's laminae. These laminae are defined on the basis of neuronal size, shape, cytological features and density and are numbered in a dorsoventral sequence. Laminae I–IV correspond to the dorsal part of the dorsal horn, and are the main site of termination of cutaneous primary afferent terminals and their collaterals. Many complex polysynaptic reflex paths (ipsilateral, contralateral, intrasegmental and intersegmental) start from this region, as also do many long ascending tract fibres which pass to higher levels. Lamina I (lamina marginalis) is a very thin layer with an ill- defined boundary at the dorsolateral tip of the dorsal horn. It has a reticular appearance, reflecting its content of intermingling bundles of coarse and fine nerve fibres. It contains small, intermediate and large neuronal somata, many of which are fusiform in shape. The much larger lamina II consists of densely packed small neurones, responsible for its dark appearance in Nissl-stained sections. With myelin stains, lamina II is characteristically distinguished from adjacent laminae by the almost total lack of myelinated fibres. Lamina II corresponds to the substantia gelatinosa. Lamina III consists of somata which are mostly larger, more variable and less closely packed than those in lamina II. It also contains many myelinated fibres. Some workers consider that the substantia gelatinosa contains part or all of lamina III as well as lamina II. The ill- defined nucleus proprius of the dorsal horn corresponds to some of the cell constituents of laminae III and IV. Lamina IV is a thick, loosely packed, heterogeneous zone permeated by fibres. Its neuronal somata vary considerably in size and shape, from small and round, through intermediate and triangular, to very large and stellate. Laminae V and VI lie at the base of the dorsal horn. They receive most of the terminals of proprioceptive primary afferents, profuse corticospinal projections from the motor and sensory cortex and input from subcortical levels, suggesting their involvement in the regulation of movement. Lamina V is a thick layer, divisible into a lateral third and medial two-thirds. Both have a mixed cell population but the former contains many prominent well-staining somata interlaced by numerous bundles of transverse, dorsoventral and longitudinal fibres. Lamina VI is most prominent in the limb enlargements. It has a densely staining medial third of small, densely packed neurones and a lateral two-thirds containing larger, more loosely packed, triangular or stellate somata. Laminae VII–IX show a variety of forms in the limb enlargements. Lamina VII includes much of the intermediate (lateral) horn. It contains prominent neurones of Clarke's column (nucleus dorsalis, nucleus thoracis, thoracic nucleus) and intermediomedial and intermediolateral cell groupings .The lateral part of lamina VII has extensive ascending and descending connections with the midbrain and cerebellum (via the spinocerebellar, spinotectal, spinoreticular, tectospinal, reticulospinal and rubrospinal tracts) and is thus involved in the regulation of posture and movement. Its medial part has numerous propriospinal reflex connections with the adjacent grey matter and segments concerned both with movement and autonomic functions. Lamina VIII spans the base of the thoracic ventral horn but is restricted to its medial aspect in limb enlargements. Its neurones display a heterogeneous mixture of sizes and shapes from small to moderately large. Lamina VIII is a mass of propriospinal interneurones. It receives terminals from the adjacent laminae, many commissural fibres from the contralateral lamina VIII, and descending connections from the interstitiospinal, reticulospinal and vestibulospinal tracts and the medial longitudinal fasciculus. The axons from these interneurones influence α motor neurone activity bilaterally, perhaps directly but more probably by excitation of small γ motor neurones supplying efferent fibres to muscle spindles. Lamina IX is a complex array of cells consisting of α and γ motor neurones and many interneurones. The large α motor neurones supply motor end- plates of extrafusal muscle fibres in striated muscle. Recording techniques have demonstrated tonic and phasic α motor neurones. The former have a lower rate of firing and lower conduction velocity and tend to innervate type S muscle units. The latter have higher conduction velocity and tend to supply fast twitch (type FR, FF) muscle units. The smaller γ motor neurones give rise to small-diameter efferent axons (fusimotor fibres), which innervate the intrafusal muscle fibres in muscle spindles. There are several functionally distinct types of γ motor neurone. The ‘static’ and ‘dynamic’ responses of muscle spindles have separate controls mediated by static and dynamic fusimotor fibres, which are distributed variously to nuclear chain and nuclear bag fibres. Lamina X surrounds the central canal and consists of the dorsal and ventral grey commissures. Dorsal horn The dorsal horn is a major zone of termination of primary afferent fibres, which enter the spinal cord through the dorsal roots of spinal nerves. Dorsal root fibres contain numerous molecules, which are either known, or suspected, to fulfil a neurotransmitter or neuromodulator role. These include glutamic acid, substance P, calcitonin gene-related peptide (CGRP), bombesin, vasoactive intestinal polypeptide (VIP), cholecystokinin (CCK), somatostatin, dynorphin and angiotensin II. Dorsal root afferents carry exteroceptive, proprioceptive and interoceptive information. Laminae I–IV are the main cutaneous receptive areas; lamina V receives fine afferents from the skin, muscle and viscera; lamina VI receives proprioceptive and some cutaneous afferents. Most, if not all, primary afferent fibres divide into ascending and descending branches on entering the cord. These then travel for variable distances in the tract of Lissauer, near the surface of the cord, and send collaterals into the subjacent grey matter. The formation, topography and division of dorsal spinal roots have all been confirmed in man. The lamina marginalis is a thin lamina of neurones at the dorsolateral tip of the dorsal horn, deep to the tract of Lissauer. Beneath it lies the substantia gelatinosa (laminae II and III), which is present at all levels, and consists mostly of small neurones, together with some larger neurones. The substantia gelatinosa receives afferents via the dorsal roots, and its neurones give rise to fibres that form the contralateral spinothalamic tract. The large propriospinal neurones of the nucleus proprius lie ventral to the substantia gelatinosa; they link segments for the mediation of intraspinal coordination . Clarke's column lies at the base of the dorsal horn. At most levels, it is near the dorsal white funiculus and may project into it. In the human spinal cord, it can usually be identified from the eighth cervical to the third or fourth lumbar segments. Neurones of Clarke's column vary in size, but most are large, especially in the lower thoracic and lumbar segments. Some send axons into the dorsal spinocerebellar tracts and others are interneurones. Lateral horn The lateral horn is a small lateral projection of grey matter located between the dorsal and ventral horns. It is present from the eighth cervical or first thoracic segment to the second or third lumbar segment. It contains the cell bodies of preganglionic sympathetic neurones. These develop in the embryonic cord dorsolateral to the central canal and migrate laterally, forming intermediomedial and intermediolateral cell columns. Their axons travel via ventral spinal roots and white rami communicantes to the sympathetic trunk. A similar cell group is found in the second to fourth sacral segments, but unlike the thoracolumbar lateral cell column, it does not form a visible lateral projection. It is the source of the sacral outflow of parasympathetic preganglionic nerve fibres. Ventral horn Neurones in the ventral horn vary in size. The largest cell bodies, which may exceed 25 μm in diameter, are those of α motor neurones, the axons of which emerge in ventral roots to innervate extrafusal fibres in striated skeletal muscles. Large numbers of smaller neurones, 15–25 μm in diameter, are also present. Some of these are γ motor neurones, which innervate intrafusal fibres of muscle spindles, and the rest are interneurones. Motor neurones utilize acetylcholine as their neurotransmitter. Considered longitudinally, ventral horn neurones are arranged in elongated groups, and form a number of separate columns, which extend through several segments. These are seen most easily in transverse sections. The ventral horn may be divided into medial, central and lateral cell columns, which all exhibit subdivision at certain levels, usually into dorsal and ventral parts . The medial group extends throughout the cord, but may be absent in the fifth lumbar and first sacral segments. In the thoracic and the upper four lumbar segments, it is subdivided into ventromedial and dorsomedial groups. In segments cranial and caudal to this region, the medial group has only a ventromedial moiety, except in the first cervical segment, where only the dorsomedial group exists. The central group of cells is the least extensive, and is found only in some cervical and lumbosacral segments. The centrally situated phrenic nucleus, containing the motor neurones that innervate the diaphragm, lies in the third to seventh cervical segments. An irregular accessory group of neurones in the upper five or six cervical segments at the ventral border of the ventral horn give rise to axons that are thought to enter the spinal accessory nerve . The lateral group of cells in the ventral horn is subdivided into ventral, dorsal and retrodorsal groups, largely confined to the spinal segments which innervate the limbs. The nucleus of Onuf, which is thought to innervate the perineal striated muscles, is a ventrolateral group of cells in the first and second sacral segments. The motor neurones of the ventral horn are somatotopically organized. The basic arrangement is that medial cell groups innervate the axial musculature, and lateral cell groups innervate the limbs. The basic building block of the somatic motor neuronal populations is represented by a longitudinally disposed group of neurones, which innervate a given muscle, and in which the α and γ motor neurones are intermixed. The various groups innervating different muscles are aggregated into two major longitudinal columns, medial and lateral. In transverse section these form the medial and lateral cell groups in the ventral horn.

The medial longitudinal motor column extends throughout the length of the spinal cord. Its neurones innervate epaxial and hypaxial muscle groups. Basically, epaxial muscles include the erector spinae group (which extend the head and vertebral column), while hypaxial muscles include prevertebral muscles of the neck, intercostal and anterior abdominal wall muscles (which flex the neck and the trunk). The epaxial muscles are innervated by branches of the dorsal primary rami of the spinal nerves, and the hypaxial muscles by branches of the ventral primary rami. In the medial column, motor neurones supplying epaxial muscles are sited ventral to those supplying hypaxial muscles. The lateral longitudinal motor column is found only in the enlargements of the spinal cord. The motor neurones in this column in the cervical and lumbar enlargements innervate muscles of the upper and lower limbs, respectively. In the cervical enlargement, motor neurones which supply muscles intrinsic to the upper limb are situated dorsally in the ventral grey column, and those innervating the most distal (hand) muscles are sited further dorsally. Motor neurones of the girdle muscles lie in the ventrolateral part of the ventral horn. There is a further somatotopic organization in that the proximal muscles of the limb are supplied from motor cell groups located more rostrally in the enlargement than those supplying the distal muscles. For example, motor neurones innervating intrinsic muscles of the hand are sited in segments C8 and T1, while motor neurones of shoulder muscles are in segments C5 and 6. A similar overall arrangement of motor neurones innervating lower limb muscles applies in the lumbosacral cord

Vascularization of the spinal cord Arteries There are two systems of blood supply to the spinal cord: vertical (due to the left and right front and rear spinal cord arteries); Horizontal (many branches spinal vertebral, deep cervical, posterior intercostal, lumbar, lateral sacral arteries). Veins of the spinal cord arteries are companions, but not the same name with them. They form osnovnohrebtsevymy veins with front and rear internal vertebral venous plexus.

Materials for self-check. A.Tasks for self- check: Draw a nucleus of the spinal cord and write pathways. B. Choose the correct answer: 1.A 30 years old patient has been arrived in the neurosurgical department with stab wounds in the area of lowthoracic spine. During the examination was found that the knife blade passed between the procesus spinosus of 10th and 11th thoracic vertebrae and damaged posterior spinal cord. The fibers of which pathways have been damaged in this case? A.fasciculus gracilis and fasciculus cuneatus B.fasciculus cuneatus C.fasciculus gracilis D.spinocerebellaris dorsalis E.spinocerebellaris ventralis 2.A. skier dosen’t have knee-jerk after after spinal cord injury. Which segments of the spinal cord were injured? A.2-4 lumbar segments of the spinal cord B.1-2 cervical segments of the spinal cord C.8-9 thoracic spinal cord segments D.10-11 thoracic spinal cord segments E.5-6 cervical segments of the spinal cord 3.A patient has lost tactile sensitivity, body position sense and vibrations sense. Which pathways were damaged? A.fasciculus cuneatus et gracilis B.tractus reticulospinalis C.tractus spinocerebellares lateralis et ventralis D.tractus rubrospinalis E.tractus tectospinalis 4.A 65 years old patient has been diagnosed with bleeding in the anterior horn of the spinal cord. Which, by the function are anterior horns? A.Motional B.Sensitive C.Sympathetic D.Parasympathetic E.Mixed 5.A patient has meningitis. The puncture of the arachnoid area was proposed. Determine shells between which it is located: A.Arachnoid and pia maters. B.The periosteum and arachnoid membrane. C.The solid and the arachnoid membranes. D.The periosteum and dura mater. E.The dura mater pia mater. 6.A patient has severe headache, stiffness in the neck muscles, repeated vomiting, pain on skull percussion, increased sensitivity to light stimuli. Diagnosis is meningitis. Lumbar puncture was shown. Point the location of the puncture: A.Between 3 and 4 lumbar vertebrae B.Between 1 and 2 lumbar vertebrae C.Between 12 thoracic and 1 lumbar vertebrae D.Between 5 lumbar and sacrum foundation E.Between 11 and 12 thoracic vertebrae 7.In order to different diagnosis of meningitis a research of cerebrospinal fluid is conducting. Where lumbar puncture is safe? A.L III -L IV B.LV - S I C.L II -L III D.L I –L II E.Th XII - L I 8.A 41 years old patient got into an infectious department of the hospital with a high body temperature. Meningeal symptoms objectively expressed. A lumbar puncture was done. What anatomical formation was punctured? A.spatium subaraсhnoideum B.spatium subdurale C.spatium epidurale D.cavum trigeminale E.cisterna cerebellomedullaris posterior 9.A car accident victim was got with injury of the rear pillars of the spinal cord. Which infringement of the functions should appear due to this injury? A.Loss of vibration sensitivity B.The loss of pain sensitivity C.Loss of the ability to voluntary movements of limbs D.The loss of temperature sensitivity E.Raising tone of skeletal muscles 10.A patient had been taken to hospital with spinal injuries. Discovered injury of rear ropes of the spinal cord at the 1st thoracic vertebra. Which pathways were affected in this case? A.Tactile and proprioceptive sensitivity B.Spina cerebellar C.Cortical-spinal D.Pain and temperature sensitivity E.Extrapyramidal

References. Basic: 1.Human Anatomy. In three volumes. Volume 2 / Edited by V.G. Koveshnikov. - Lugansk: LTD «Virtualnaya realnost», 2008. – 248p. 2.Human Anatomy. In three volumes. Volume 3 / Edited by V.G. Koveshnikov. - Lugansk: LTD «Virtualnaya realnost», 2009. – 384p. 3.Gray′s anatomy for students / Richard L. Drake, A. Wayne Vogl, and Adam W. M. Mitchell; illustrations by Richard M. Tibbitts and Paul E. Richardson; photographs by Ansell Horn. – 2nd ed. 2012 – 1103p. 4.Sobotta Atlas of Human Anatomy / Edited by R. Putz and R. Pabst, 14th ed. – Elsevier GmbH, Munich, 2008 . – 895p. 5.Clay JH, Pounds DM. Basic Clinical Massage Therapy: Integrating Anatomy and Treatment. 2003. 6.Grant′s atlas of anatomy ∕ Anne M.R., Arthur F. Dalley II, 12th ed. - Baltimore: Wiliams & Wolters, 2009. – 864 p. 7.Martini Frederic H. Martini′s atlas of the human body, 8th ed. – Pearson Education, 2009. – 250p. 8.Atlas of Human Anatomy / Frank H. Netter, M.D. Arthur F. Dalley; 2nd ed. // ILS, Medimedia USA Company, 1997. – 548p. The additional literature: 1.Langman J. Medical embryology / Langman J. – Baltimore, London, 1981. – 384p. 2.Crouse G.S. Development of the female urogenital system / G.S. Crouse // Semin. Reprod. Endocrinol. – 1986. – V.4, №1. – P. 1-11. 3.Beck F. Human embryology: 2 ed / F. Beck, D. Mossat, D. Davies. - Oxford: Blackwell, 1985. – V. 11. – 372p. 4.Moore Keith L. Clinically oriented anatomy: third ed / Keith L. Moore. – 1992. - 917p. 5.Clinical Anatomy. Applied anatomy for clinical students and junior doctors: eleventh edition / Harold Ellis // Oxford, UK: Blackwell publishing. – 2006. – 455p. 6.Pocket atlas of Human Anatomy / Heinz Feneis, Wolfgang Dauber // Thieme, Stuttgart. – 2000. – 510p. 7. https://human.biodigital.com/ 8. http://anatom.ua/nomina-anatomica/

Topic 22. Medulla oblongata, pons.

1. Relevance of the topic: Knowledge of anatomy section and necessary for students of all specialties for further study. 2. The specific aims: Explain to students general characteristics of the brain and its components, the development of the brain. Examine the outer structure of the medulla oblongata and the bridge location of gray and white matter. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). The preceding The acquired knowledge subjects Biology The phylogeny of the nervous system; Topics for further study. 4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class.

MYELENCEPHALON; Medulla oblongata MEDULLA OBLONGATA; BULBUS

Fissura mediana anterior Anterior median fissure

Foramen caecum medullae oblongataeBlind hole medulla

Pyramis medullae oblongatae The pyramids of the medulla oblongata

Funiculus lateralis lateral cord Oliva Olive

Substantia alba White matter

Tractus pyramidalis pyramidal way

Fibrae corticospinales Cortical-spinal fibers

Fibrae corticonucleares bulbi Cortex-core fibers of the medulla oblongata

Fasciculus gracilis Gentle bunch

Fasciculus cuneatus wedge-shaped beam

Fibrae arcuatae internae The internal arcuate fibers

Decussatio lemnisci medialis Crossroads medial loop Tractus spinalis nervi trigemini Spinal trigeminal nerve path Tractus spinoolivaris Spina oiled path Tractus olivocerebellaris Oils-cerebellar path Pedunculus cerebellaris inferior Lower cerebellar legs Tractus solitaries Single way

4.2. Theoretical questions for the class: 1. The development of the brain. 2. The parts of the brain. Brainstem. 3. The external structure of the medulla oblongata? 4. The internal structure of the medulla oblongata? The nuclei of the cranial nerves? 5. Bridge: external and internal structure? The nuclei of the cranial nerves? 6. Pathways medulla oblongata? The medial loop. 7. Pathways bridge 4.3. Practical tasks pertaining to the topic and to be completed during the class: the preparations, tables, models to study the structure of the medulla oblongata and the bridge, the gray and white matter. To know the anatomy of the medulla oblongata and the bridge, the external structure, topography. The content of the topic: The brain - Encephalon Brainstem, including the medulla oblongata, the bridge and the average brain weighs a newborn less than 10 g (2.7% by weight of the brain). Most formed until the birth roof brainstem its phylogenetically older formations, poorly developed phylogenetic youth front of the barrel. Differentiation of nerve nuclei and the ways in roof continues in the first months and years of life, and in the front of the brain stem ends in older children. The medulla oblongata connects the pons superiorly with the spinal cord inferiorly. The junction of the medulla and spinal cord is at the origin of the anterior and posterior roots of the first cervical spinal nerve, which corresponds approximately to the level of the foramen magnum. The medulla oblongata is conical in shape, its broad extremity being directed superiorly. The central canal of the spinal cord continues upward into the lower half of the medulla; in the upper half of the medulla, it expands as the cavity of the fourth ventricle. On the anterior surface of the medulla is the anterior median fissure, which is continuous inferiorly with the anterior median fissure of the spinal cord. On each side of the median fissure, there is a swelling called the pyramid. The pyramids are composed of bundles of nerve fibers, corticospinal fibers, which originate in large nerve cells in the precentral gyrus of the cerebral cortex. The pyramids taper inferiorly, and it is here that the majority of the descending fibers cross over to the opposite side, forming the decussation of the pyramids. The anterior external arcuate fibers are a few nerve fibers that emerge from the anterior median fissure above the decussation and pass laterally over the surface of the medulla oblongata to enter the cerebellum. Posterolateral to the pyramids are the olives, which are oval elevations produced by the underlying inferior olivary nuclei. In the groove between the pyramid and the olive emerge the rootlets of the hypoglossal nerve. Posterior to the olives are the inferior cerebellar peduncles, which connect the medulla to the cerebellum. In the groove between the olive and

the inferior cerebellar peduncle emerge the roots of the glossopharyngeal and vagus nerves and the cranial roots of the accessory nerve. The posterior surface of the superior half of the medulla oblongata forms the lower part of the floor of the fourth ventricle. The posterior surface of the inferior half of the medulla is continuous with the posterior aspect of the spinal cord and possesses a posterior median sulcus. On each side of the median sulcus, there is an elongated swelling, the gracile tubercle, produced by the underlying gracile nucleus. Lateral to the gracile tubercle is a similar swelling, the cuneate tubercle, produced by the underlying cuneate nucleus. INTERNAL STRUCTURE As in the spinal cord, the medulla oblongata consists of white matter and gray matter, but a study of transverse sections of this region shows that they have been extensively rearranged. This rearrangement can be explained embryologically by the expansion of the neural tube to form the hindbrain vesicle, which becomes the fourth ventricle. The extensive lateral spread of the fourth ventricle results in an alteration in the position of the derivatives of the alar and basal plates of the embryo. To assist in understanding this concept, remember that in the spinal cord the derivatives of the alar and basal plates are situated posterior and anterior to the sulcus limitans, respectively, and in the case of the medulla oblongata, they are situated lateral and medial to the sulcus limitans, respectively. The internal structure of the medulla oblongata is considered at four levels: (1) level of decussation of pyramids, (2) level of decussation of lemnisci, (3) level of the olives, and (4) level just inferior to the pons. Level of Decussation of Pyramids A transverse section through the inferior half of the medulla oblongata passes through the decussation of the pyramids, the great motor decussation. In the superior part of the medulla, the corticospinal fibers occupy and form the pyramid, but inferiorly, about three-fourths of the fibers cross the median plane and continue down the spinal cord in the lateral white column as the lateral corticospinal tract. As these fibers cross the midline, they sever the continuity between the anterior column of the gray matter of the spinal cord and the gray matter that surrounds the central canal. The fasciculus gracilis and the fasciculus cuneatus continue to ascend superiorly posterior to the central gray matter. The nucleus gracilis and the nucleus cuneatus appear as posterior extensions of the central gray matter. The substantia gelatinosa in the posterior gray column of the spinal cord becomes continuous with the inferior end of the nucleus of the spinal tract of the trigeminal nerve. The fibers of the tract of the nucleus are situated between the nucleus and the surface of the medulla oblongata. The lateral and anterior white columns of the spinal cord are easily identified in these sections, and their fiber arrangement is unchanged. Level of Decussation of Lemnisci A transverse section through the inferior half of the medulla oblongata, a short distance above the level of the decussation of the pyramids, passes through the decussation of lemnisci, the great sensory decussation. The decussation of the lemnisci takes place anterior to the central gray matter and posterior to the pyramids. It should be understood that the lemnisci have been formed from the internal arcuate fibers, which have emerged from the anterior aspects of the nucleus gracilis and nucleus cuneatus. The internal arcuate fibers first travel anteriorly and laterally around the central gray matter. They then curve medially toward the midline, where they decussate with the corresponding fibers of the opposite side. The nucleus of the spinal tract of the trigeminal nerve lies lateral to the internal arcuate fibers. The spinal tract of the trigeminal nerve lies lateral to the nucleus. The lateral and anterior spinothalamic tracts and the spinotectal tracts occupy an area lateral to the decussation of the lemnisci. They are very close to one another and collectively are known as the spinal lemniscus. The spinocerebellar, vestibulospinal, and the rubrospinal tracts are situated in the anterolateral region of the medulla oblongata. Level of the Olives A transverse section through the olives passes across the inferior part of the fourth ventricle. The amount of gray matter has increased at this level owing to the presence of the olivary nuclear complex; the nuclei of the vestibulocochlear, glossopharyngeal, vagus, accessory, and hypoglossal nerves; and the arcuate nuclei. Olivary Nuclear Complex The largest nucleus of this complex is the inferior olivary nucleus. The gray matter is shaped like a crumpled bag with its mouth directed medially; it is responsible for the elevation on the surface of the medulla called the olive. Smaller dorsal and medial accessory olivary nuclei also are present. The cells of the inferior olivary nucleus send fibers medially across the midline to enter the cerebellum through the inferior cerebellar peduncle. Afferent fibers reach the inferior olivary nuclei from the spinal cord (the spino-olivary tracts) and from the cerebellum and cerebral cortex. The function of the olivary nuclei is associated with voluntary muscle movement. Vestibulocochlear Nuclei The vestibular nuclear complex is made up of the following nuclei. (1) medial vestibular nucleus, (2) inferior vestibular nucleus, (3) lateral vestibular nucleus, and (4) superior vestibular nucleus. The details of these nuclei and their connections are discussed later. The medial and inferior vestibular nuclei can be seen on section at this level. There are two cochlear nuclei. The anterior cochlear nucleus is situated on the anterolateral aspect of the inferior cerebellar peduncle, and the posterior cochlear nucleus is situated on the posterior aspect of the peduncle lateral to the floor of the fourth ventricle. The connections of these nuclei are described later. The Nucleus Ambiguus The nucleus ambiguus consists of large motor neurons and is situated deep within the reticular formation. The emerging nerve fibers join the glossopharyngeal, vagus, and cranial part of the accessory nerve and are distributed to voluntary skeletal muscle. Central Gray Matter The central gray matter lies beneath the floor of the fourth ventricle at this level. Passing from medial to lateral, the following important structures may be recognized: (1) the hypoglossal nucleus, (2) the dorsal nucleus of the vagus, (3) the nucleus of the tractus solitarius, and (4) the medial and inferior vestibular nuclei. The nucleus ambiguus, referred to above, has become deeply placed within the reticular formation. The arcuate nuclei are thought to be inferiorly displaced pontine nuclei and are situated on the anterior surface of the pyramids. They receive nerve fibers from the cerebral cortex and send efferent fibers to the cerebellum through the anterior external arcuate fibers. The pyramids containing the corticospinal and some corticonuclear fibers are situated in the anterior part of the medulla separated by the anterior median fissure; the corticospinal fibers descend to the spinal cord, and the corticonuclear fibers are distributed to the motor nuclei of the cranial nerves situated within the medulla. The medial lemniscus forms a flattened tract on each side of the midline posterior to the pyramid. These fibers emerge from the decussation of the lemnisci and convey sensory information to the thalamus. The medial longitudinal fasciculus forms a small tract of nerve fibers situated on each side of the midline posterior to the medial lemniscus and anterior to the hypoglossal nucleus. It consists of ascending and descending fibers. The inferior cerebellar peduncle is situated in the posterolateral corner of the section on the lateral side of the fourth ventricle. The spinal tract of the trigeminal nerve and its nucleus are situated on the anteromedial aspect of the inferior cerebellar peduncle. The anterior spinocerebellar tract is situated near the surface in the interval between the inferior olivary nucleus and the nucleus of the spinal tract of the trigeminal nerve. The spinal lemniscus, consisting of the anterior spinothalamic, the lateral spinothalamic, and spinotectal tracts, is deeply placed. The reticular formation, consisting of a diffuse mixture of nerve fibers and small groups of nerve cells, is deeply placed posterior to the olivary nucleus. The reticular formation represents, at this level, only a small part of this system, which is also present in the pons and midbrain. The glossopharyngeal, vagus, and cranial part of the accessory nerves can be seen running forward and laterally through the reticular formation. The nerve fibers emerge between the olives and the inferior cerebellar peduncles. The hypoglossal nerves also run anteriorly and laterally through the reticular formation and emerge between the pyramids and the olives. Level Just Inferior to the Pons There are no major changes, in comparison to the previous level, in the distribution of the gray and white matter. The lateral vestibular nucleus has replaced the inferior vestibular nucleus, and the cochlear nuclei now are visible on the anterior and posterior surfaces of the inferior cerebellar peduncle. The pons is anterior to the cerebellum and connects the medulla oblongata to the midbrain. It is about 1 inch (2.5 cm) long and owes its name to the appearance presented on the anterior surface, which is that of a bridge connecting the right and left cerebellar hemispheres. The anterior surface is convex from side to side and shows many transverse fibers that converge on each side to form the middle cerebellar peduncle. There is a shallow groove in the midline, the basilar groove, which lodges the basilar artery. On the anterolateral surface of the pons, the trigeminal nerve emerges on each side. Each nerve consists of a smaller, medial part, known as the motor root, and a larger, lateral part, known as the sensory root. In the groove between the pons and the medulla oblongata, there emerge, from medial to lateral, the abducent, facial, and vestibulocochlear nerves. The posterior surface of the pons is hidden from view by the cerebellum. It forms the upper half of the floor of the fourth ventricle and is triangular in shape. The posterior surface is limited laterally by the superior cerebellar peduncles and is divided into symmetrical halves by a median sulcus. Lateral to this sulcus is an elongated elevation, the medial eminence, which is bounded laterally by a sulcus, the sulcus limitans. The inferior end of the medial eminence is slightly expanded to form the facial colliculus, which is produced by the root of the facial nerve winding around the nucleus of the abducent nerve. The floor of the superior part of the sulcus limitans is bluish-gray in color and is called the substantia ferruginea; it owes its color to a group of deeply pigmented nerve cells. Lateral to the sulcus limitans is the area vestibuli produced by the underlying vestibular nuclei. INTERNAL STRUCTURE OF THE PONS For purposes of description, the pons is commonly divided into a posterior part, the tegmentum, and an anterior basal part by the transversely running fibers of the trapezoid body. The structure of the pons may be studied at two levels: (1) transverse section through the caudal part, passing through the facial colliculus, and (2) transverse section through the cranial part, passing through the trigeminal nuclei. See Table 5- 2 for a comparison of the two levels of the pons and the major structures present at each level. Transverse Section Through the Caudal Part The medial lemniscus rotates as it passes from the medulla into the pons. It is situated in the most anterior part of the tegmentum with its long axis running transversely. The medial lemniscus is accompanied by the spinal and lateral lemnisci. The facial nucleus lies posterior to the lateral part of the medial lemniscus. The fibers of the facial nerve wind around the nucleus of the abducent nerve, producing the facial colliculus. The fibers of the facial nerve then pass anteriorly between the facial nucleus and the superior end of the nucleus of the spinal tract of the trigeminal nerve. The medial longitudinal fasciculus is situated beneath the floor of the fourth ventricle on either side of the midline. The medial longitudinal fasciculus is the main pathway that connects the vestibular and cochlear nuclei with the nuclei controlling the extraocular muscles (oculomotor, trochlear, and abducent nuclei). The medial vestibular nucleus is situated lateral to the abducent nucleus and is in close relationship to the inferior cerebellar peduncle. The superior part of the lateral and the inferior part of the superior vestibular nucleus are found at this level. The posterior and anterior cochlear nuclei are also found at this level. The spinal nucleus of the trigeminal nerve and its tract lie on the anteromedial aspect of the inferior cerebellar peduncle. The trapezoid body is made up of fibers derived from the cochlear nuclei and the nuclei of the trapezoid body. They run transversely in the anterior part of the tegmentum. The basilar part of the pons, at this level, contains small masses of nerve cells called pontine nuclei. The corticopontine fibers of the crus cerebri of the midbrain terminate in the pontine nuclei. The axons of these cells give origin to the transverse fibers of the pons, which cross the midline and intersect the corticospinal and corticonuclear tracts, breaking them up into small bundles. The transverse fibers of the pons enter the middle cerebellar peduncle and are distributed to the cerebellar hemisphere. This connection forms the main pathway linking the cerebral cortex to the cerebellum. Transverse Section Through the Cranial Part The internal structure of the cranial part of the pons is similar to that seen at the caudal level, but it now contains the motor and principal sensory nuclei of the trigeminal nerve. The motor nucleus of the trigeminal nerve is situated beneath the lateral part of the fourth ventricle within the reticular formation. The emerging motor fibers travel anteriorly through the substance of the pons and exit on its anterior surface. The principal sensory nucleus of the trigeminal nerve is situated on the lateral side of the motor nucleus; it is continuous inferiorly with the nucleus of the spinal tract. The entering sensory fibers travel through the substance of the pons and lie lateral to the motor fibers. The superior cerebellar peduncle is situated posterolateral to the motor nucleus of the trigeminal nerve. It is joined by the anterior spinocerebellar tract. The trapezoid body and the medial lemniscus are situated in the same position as they were in the previous section. The lateral and spinal lemnisci lie at the lateral extremity of the medial lemniscus.

Materials for self-check: A. Tasks for self-c check: Draw a nucleus of the medulla oblongata and the bridge and prescribe pathways. B. Choose the correct answer: 1.From the medulla oblongata, namely the nucleus cuneatus et nucleus gracilis starts: A.tractus bulbo-thalamicus B.tractus spinothalamicus anterior C.tractus spinothalamicus posterior D.tractus corticospinalis E.tractus corticonuclearis 2.Patient has a damage of the pathways that starts from the pontis, namely from the auditory nuclei vestibulocochlear nerve. Name it: A.lateral loop B.medial loop C.tractus corticopontocerebellaris D.tractus spinothalamicus anterior E.tractus bulbo-thalamicus 3.The pontis connects to the cerebellum through: A.medialis peduncule of cerebellum. B.superior peduncule of cerebellum. C.inferior peduncule of cerebellum. D.Through all peduncles E.There is no right answer 4.A 58 years-old woman addressed to the doctor with complaints on violations of the tongue taste sensitivity. An examination using MRI has found a small hemorrhage in the area of the medulla oblongata. The damage of which the nuclei of the medulla oblongata could result in a violation of taste? A.nucleus tracti solitarii B.nucleus ambiguus C.nucleus nervi hypoglossi D.nucleus salivatorius inferior E.dorsalis nuclei cochleares

5.60-years-old woman addressed to the doctor with complaints on the difficulties of movements of the tongue that interferes the abilities to speak and eat. Examination of brain using IRAs showed that the patient has a small hemorrhage in the lower part of medulla oblongata. Which the nuclei of the medulla oblongata are damaged? A.nuclei nervi hypoglossi. B.nuclei salivatorius inferior C.nuclei nervi accessorii D.nuclei ambiguus E.nuclei tracti solitarii 6.After stroke (bleeding) in the brain stem the patient has disorders in respiratory and cardiovascular activity. In which brain structure is localized pathological process? A.In nuclei dorsalis nervi vagi B.in the ventral part of the pons C.In nuclei of formatio reticularis of medulla oblongata D.In nuclei of formatio reticularis of the pons. E.In nucleus ambiguus of medulla oblongata 7.The patient has a bleeding in the back of the medulla oblongata. The patient complains on respiratory disorders. Which nuclei are damaged? A.Nuclei – respiration centers B.nuclei nervus glossopharyngeus C.nuclei nervi accessorii D.nuclei nervi hypoglossi E.Nuclei - centers of the cardiovascular system. 8.During the examination of the patient using IRAs in the brain in the area of the pons doctor saw the tumor, which held its ventral part. What anatomical structure divides the pons into dorsal and ventral parts? A.fibrosi corpus trapezoideum B.nuclei nervus trigeminus C.nuclei nervus abducens D.nuclei nervus facialis E.nuclei corpus trapezoideum. 9.The patient arrived to the clinic with damaged skull base in the slope area. Intensive therapy was appointed to prevent extensive swelling and compression of the brain, where are situated respiratory and vasomotor centers. Point their location: A.in myelencephalon B.in mesencephalon C.in pons D.in cerebellum. E.in the whole brain stem 10.When examining patients with disorders of auditory function was found that the pathological process is localized at the lemniscus lateralis formation. At the level of which brain it is normally formed? A.metencephalon (pons). B.cervical. C.thoracic. D.medulla oblongata. E.Mesencephalon

Topic 23. Cerebellum. The isthmus of the fhombencephalon. 1. Relevance of the topic: If the damage cerebellum occur dystaxia regulation of muscle tone, balance the body. Perfect knowledge of the structure of the cerebellum help determine the correct diagnosis of the patient. 2. The specific aims: Explain the general characteristics of hindbrain. To explain: - the location of the cerebellum; - Diamond-shaped isthmus brain; - External structure of the cerebellum; - The internal structure of the cerebellum; - Cerebellar pathways;

CEREBELLUM Cerebellum

Vestibulocerebellum Vestibular-cerebellar

Pontocerebellum Bridge cerebellar

Neocerebellum Neo cerebellum Lobus cerebelli anterior Front proportion cerebellum Lobulus centralis Central share Nuclei cerebelli cerebellar nuclei Nucleus dentatus; Tooth core Nucleus emboliformis core cortex Nucleus globosus globular core - Isthmus diamond-shaped structure of the brain. 3. Basic knowledge and skills necessary to study the topic (inter- disciplinary integration).

Disciplines Know Be able Biology The development of the nervous system in mammals. Show the location of the Features of the cerebellum in main parts of the central Histology Themammals. structure of gray and white Tonervous be ablesystem to distinguish matter of the cerebellum. between gray and white matter, the nucleus of the cerebellum. 4. The tasks for students' individual work.

4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class. 4.2. Theoretical questions for the class: 1. What are the department is diamond-shaped brain? 2. The boundaries of the location of the cerebellum. 3. Derivatives bubble which brain structures are related to the back of the brain? 4. What are the parts of the cerebellum is? 5. Location of diamond-shaped isthmus brain. 6. The external structure of the cerebellum. 7. The internal structure of the cerebellum. 8. Characteristics of the cerebellar nuclei. 9. 3 structures which combined stem cerebellum? 10. Name the components of the diamond-shaped isthmus brain 11. Pathways of the cerebellum 4.3. Practical tasks pertaining to the topic and to be completed during the class: 1. Show on isolated preparations brain stem. 2. Show location, boundaries cerebellum, isthmus, diamond-shaped brain 3. Be able to show hemisphere of the cerebellum worm surface cracks, slices, piece, legs cerebellum 4.Cerebellum section showing the gray and white matter, the nucleus of the cerebellum. 5.Display components isthmus diamond-shaped brain (redunculi cerebellares superiors, vellum medullare superius, trigonum lemnisci). The content of the topic: Cerebellum - cerebellum The cerebellum is situated in the posterior cranial fossa and covered superiorly by the tentorium cerebelli. It is the largest part of the hindbrain and lies posterior to the fourth ventricle, the pons, and the medulla oblongata. The cerebellum is somewhat ovoid in shape and constricted in its median part. It consists of two cerebellar hemispheres joined by a narrow median vermis. The cerebellum is connected to the posterior aspect of the brainstem by three symmetrical bundles of nerve fibers called the superior, middle, and inferior cerebellar peduncles. The cerebellum is divided into three main lobes: the anterior lobe, the middle lobe, and the flocculonodular lobe. The anterior lobe may be seen on the superior surface of the cerebellum and is separated from the middle lobe by a wide V-shaped fissure called the primary fissure. The middle lobe (sometimes called the posterior lobe), which is the largest part of the cerebellum, is situated between the primary and uvulo-nodular fissures. The flocculonodular lobe is situated posterior to the uvulonodular fissure. A deep horizontal fissure that is found along the margin of the cerebellum separates the superior from the inferior surfaces; it is of no morphological or functional significance. STRUCTURE OF THE CEREBELLUM The cerebellum is composed of an outer covering of gray matter called the cortex and inner white matter. Embedded in the white matter of each hemisphere are three masses of gray matter forming the intracerebellar nuclei. Structure of the Cerebellar Cortex The cerebellar cortex can be regarded as a large sheet with folds lying in the coronal or transverse plane. Each fold or folium contains a core of white matter covered superficially by gray matter. A section made through the cerebellum parallel with the median plane divides the folia at right angles, and the cut surface has a branched appearance, called the arbor vitae. The gray matter of the cortex throughout its extent has a uniform structure. It may be divided into three layers: (1) an external layer, the molecular layer, (2) a middle layer, the Purkinje cell layer; and (3) an internal layer, the granular layer. Molecular Layer The molecular layer contains two types of neurons: the outer stellate cell and the inner basket cell. These neurons are scattered among dendritic arborizations and numerous thin axons that run parallel to the long axis of the folia. Neuroglial cells are found between these structures. Purkinje Cell Layer The Purkinje cells are large Golgi type I neurons. They are flask-shaped and are arranged in a single layer. In a plane transverse to the folium, the dendrites of these cells are seen to pass into the molecular layer, where they undergo profuse branching. The primary and secondary branches are smooth, and subsequent branches are covered by short, thick dendritic spines. It has been shown that the spines form synaptic contacts with the parallel fibers derived from the granule cell axons. At the base of the Purkinje cell, the axon arises and passes through the granular layer to enter the white matter. On entering the white matter, the axon acquires a myelin sheath, and it terminates by synapsing with cells of one of the intracerebellar nuclei. Collateral branches of the Purkinje axon make synaptic contacts with the dendrites of basket and stellate cells of the granular layer in the same area or in distant folia. A few of the Purkinje cell axons pass directly to end in the vestibular nuclei of the brainstem. Granular Layer The granular layer is packed with small cells with densely staining nuclei and scanty cytoplasm. Each cell gives rise to four or five dendrites, which make clawlike endings and have synaptic contact with mossy fiber input. The axon of each granule cell passes into the molecular layer, where it bifurcates at a T junction, the branches running parallel to the long axis of the cerebellar folium. These fibers, known as parallel fibers, run at right angles to the dendritic processes of the Purkinje cells. Most of the parallel fibers make synaptic contacts with the spinous processes of the dendrites of the Purkinje cells. Neuroglial cells are found throughout this layer. Scattered throughout the granular layer are Golgi cells. Their dendrites ramify in the molecular layer, and their axons terminate by splitting up into branches that synapse with the dendrites of the granular cells. Functional Areas of the Cerebellar Cortex Clinical observations by neurologists and neurosurgeons and the experimental use of the PET scan have shown that it is possible to divide up the cerebellar cortex into three functional areas. The cortex of the vermis influences the movements of the long axis of the body, namely, the neck, the shoulders, the thorax, the abdomen, and the hips. Immediately lateral to the vermis is a so-called intermediate zone of the cerebellar hemisphere. This area has been shown to control the muscles of the distal parts of the limbs, especially the hands and feet. The lateral zone of each cerebellar hemisphere appears to be concerned with the planning of sequential movements of the entire body and is involved with the conscious assessment of movement errors. Intracerebellar Nuclei Four masses of gray matter are embedded in the white matter of the cerebellum on each side of the midline. From lateral to medial, these nuclei are the dentate, the emboliform, the globose, and the fastigial. The dentate nucleus is the largest of the cerebellar nuclei. It has the shape of a crumpled bag with the opening facing medially. The interior of the bag is filled with white matter made up of efferent fibers that leave the nucleus through the opening to form a large part of the superior cerebellar peduncle. The emboliform nucleus is ovoid and is situated medial to the dentate nucleus, partially covering its hilus. The globose nucleus consists of one or more rounded cell groups that lie medial to the emboliform nucleus. The fastigial nucleus lies near the midline in the vermis and close to the roof of the fourth ventricle; it is larger than the globose nucleus. The intracerebellar nuclei are composed of large, multipolar neurons with simple branching dendrites. The axons form the cerebellar outflow in the superior and inferior cerebellar peduncles. White Matter There is a small amount of white matter in the vermis; it closely resembles the trunk and branches of a tree and thus is termed the arbor vitae. There is a large amount of white matter in each cerebellar hemisphere. The white matter is made up of three groups of fibers: (1) intrinsic, (2) afferent, and (3) efferent. The intrinsic fibers do not leave the cerebellum but connect different regions of the organ. Some interconnect folia of the cerebellar cortex and vermis on the same side; others connect the two cerebellar hemispheres together. The afferent fibers form the greater part of the white matter and proceed to the cerebellar cortex. They enter the cerebellum mainly through the inferior and middle cerebellar peduncles. The efferent fibers constitute the output of the cerebellum and commence as the axons of the Purkinje cells of the cerebellar cortex. The great majority of the Purkinje cell axons pass to and synapse with the neurons of the cerebellar nuclei (fastigial, globose, emboliform, and dentate). The axons of the neurons then leave the cerebellum. A few Purkinje cell axons in the flocculonodular lobe and in parts of the vermis bypass the cerebellar nuclei and leave the cerebellum without synapsing. Fibers from the dentate, emboliform, and globose nuclei leave the cerebellum through the superior cerebellar peduncle. Fibers from the fastigial nucleus leave through the inferior cerebellar peduncle. CEREBELLAR CORTICAL MECHANISMS As a result of extensive cytological and physiological research, certain basic mechanisms have been attributed to the cerebellar cortex. The climbing and the mossy fibers constitute the two main lines of input to the cortex and are excitatory to the Purkinje cells. The climbing fibers are the terminal fibers of the olivocerebellar tracts. They are so named because they ascend through the layers of the cortex like a vine on a tree. They pass through the granular layer of the cortex and terminate in the molecular layer by dividing repeatedly. Each climbing fiber wraps around and makes a large number of synaptic contacts with the dendrites of a Purkinje cell. A single Purkinje neuron makes synaptic contact with only one climbing fiber. However, one climbing fiber makes contact with one to ten Purkinje neurons. A few side branches leave each climbing fiber and synapse with the stellate cells and basket cells. The mossy fibers are the terminal fibers of all other cerebellar afferent tracts. They have multiple branches and exert a much more diffuse excitatory effect. A single mossy fiber may stimulate thousands of Purkinje cells through the granule cells. What then is the function of the remaining cells of the cerebellar cortex, namely, the stellate, basket, and Golgi cells? Neurophysiological research, using microelectrodes, would indicate that they serve as inhibitory interneurons. It is believed that they not only limit the area of cortex excited but influence the degree of Purkinje cell excitation produced by the climbing and mossy fiber input. By this means, fluctuating inhibitory impulses are transmitted by the Purkinje cells to the intracerebellar nuclei, which, in turn, modify muscular activity through the motor control areas of the brainstem and cerebral cortex. It is thus seen that the Purkinje cells form the center of a functional unit of the cerebellar cortex. Intracerebellar Nuclear Mechanisms The deep cerebellar nuclei receive afferent nervous information from two sources: (1) the inhibitory axons from the Purkinje cells of the overlying cortex, and (2) the excitatory axons that are branches of the afferent climbing and rnos; fibers that are passing to the overlying cortex. In this mai ner, a given sensory input to the cerebellum sends excit tory information to the nuclei, which a short time later, r ceive cortical processed inhibitory information from tr: Purkinje cells. Efferent information from the deep cerebell; nuclei leaves the cerebellum to be distributed to the r mainder of the brain and spinal cord. Cerebellar Peduncles The cerebellum is linked to other parts of the central nervous system by numerous efferent and afferent fibers that a grouped together on each side into three large bundles, or peduncles. The superior cerebellar peduncli connect the cerebellum to the midbrain, the middle cer bellar peduncles connect the cerebellum to the pons, and the inferior cerebellar peduncles connect the cerebellum the medulla oblongata. Cerebellum Newborn weighs in at 20 grams, which is 5.4% of the weight of the entire brain. In the early years of the cerebellum grows rapidly, and 6 years of its weight reaches the lower limit weight gain in adults (142-150 g 125-135 g of boys and girls). The relative weight of the cerebellum is increased to 10% by weight of the brain. Especially strong developing cerebellar hemisphere.

Materials for self-check: A. Tasks for self- check: Draw and write cerebellar nuclei pathways that take place in the upper, middle and lower legs. B. Choose the correct answer: 1.The patient has a tumor in site of connection with the cerebellum and medulla oblongata. It is: A.pedunculi cerebellares inferiores B.pedunculi cerebellares superiores C.pedunculi cerebellares medii D.Leaflets of the cerebellum. E.cerebellar vermis 2.A patient has a tumor in site of connection with the cerebellum and pontis. It is: A.pedunculi cerebellares medii B.pedunculi cerebellares superiores C.pedunculi cerebellares inferiores D.Leaflets of the cerebellum. E.cerebellar vermis 3.A patient has a tumor in site of connection with the cerebellum and average brain. It is: A.pedunculi cerebellares superiores B.pedunculi cerebellares inferiores. C.pedunculi cerebellares medii D.Leaflets of the cerebellum. E.cerebellar vermis 4.The cerebellum is connected with other parts of the central nervous system by: A.3 pairs of peduncles B.5 peduncles C.2 peduncles D.3 peduncles E.4 peduncles 5.A patient was diagnosed with a damage of superior cerebellar peduncles, superior medullary velum and trigone of lateral lemniscus. These formations belong to: A.isthmus rhombencephali B.medulla oblongata C.pons D.The spinal cord E.the midbrain 6.Cerebellar tumor has spread to all layers of the cerebellar cortex. It consists of: A.3 stratum of nerve cells B.2 stratum of nerve cells C.1 stratum of nerve cells D.only of nerve processes 7.During the work man gets tired quickly. In a standing position with closed eyes he staggers, loses balance. Tonus of skeletal muscle is low. Which of the following brain structures is affected? A.cerebellum B.the pons C.nucleus of accessory nerve D.nucleus of the vagus nerve E.medulla oblongata 8.During the examination of woman’s brain bleeding was found, that is localized in the superior cerebellar peduncle. Which ways cross it? A.anterior spinocerebellar tract, tractus tectospinalis B.posterior and anterior spinocerebellar tract, olivocerebellar tract C.posterior spinocerebellar tract, olivocerebellar tract, vestibulocerebellar tract, lateral vestibulospinal tract D.anterior spinocerebellar tract, olivocerebellar tract, vestibulocerebellar tract, lateral vestibulospinal tract. E.pontocerebellaris tract. 9.During the examination of woman’s brain bleeding was found, that is localized in the medial cerebellar peduncle. Which ways cross it? A.pontocerebellaris tract. B.posterior and anterior spinocerebellar tract, olivocerebellar tract C.posterior spinocerebellar tract, olivocerebellar tract, vestibulocerebellar tract, lateral vestibulospinal tract . D.anterior spinocerebellar tract, olivocerebellar tract, vestibulocerebellar tract, lateral vestibulospinal tract. E.anterior spinocerebellar tract, tractus tectospinalis. 10.During the examination of woman’s brain bleeding was found, that is localized in the inferior cerebellar peduncle. Which ways cross it? A.posterior spinocerebellar tract, olivocerebellar tract, vestibulocerebellar tract, lateral vestibulospinal tract . B.posterior and anterior spinocerebellar tract, olivocerebellar tract C.anterior spinocerebellar tract, olivocerebellar tract, vestibulocerebellar tract, lateral vestibulospinal tract. D.pontocerebellaris tract. E.anterior spinocerebellar tract, tractus tectospinalis.

Topic 24. The fourth ventricle. Rhomboid fossa. 1. Relevance of the topic: Defeat cores bridge and the medulla oblongata cause serious damage to the health of the patient, can cause death. Knowledge of localization, functionality cores will help in the resolution of the correct diagnosis of the patient. 2. The specific aims: To analyze the functionality of the nuclei of the bridge and the medulla oblongata. Explain: - Structure of the foreign rhomboid fossa; - The projection of sensory nuclei in diamond-shaped hole; - Projection motor nuclei in diamond-shaped hole; - Projection parasympathetic nuclei in diamond-shaped hole; - IV ventricle structure and location of the IV ventricle. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). Disciplines Know Be able Biology The development of the Show the location of the nervous system in mammals. main parts of the central Features diamond-shaped nervous system lesions of the brain of Histology Thevertebrates. structure of the nucleus To be able to distinguish rhomboid fossa between gray and white matter rhomboid fossa 4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class.

Ventriculus quartus The fourth ventricle

Fossa rhomboidea Diamond shaped hole Trigonum nervi hypoglossi Triangle hypoglossal nerve

Trigonum nervi vagi Triangle vagus nerve

Plexus choroideus Vascular plexus 4.2. Theoretical questions for the class: 1. What are the department is diamond-shaped hole? 2. The external structure of the dorsal surface of the medulla oblongata. 3. The external structure of the dorsal surface of the bridge. 4. Name the legs of the cerebellum, which they interfaced structures. 5. Placement and connection IV ventricle. 6. Projection sensitive cranial nerve nuclei in diamond-shaped hole. 7. Projection motor cranial nerve nuclei in diamond-shaped hole. 8. The projection parasympathetic cranial nerve nuclei in diamond-shaped hole. 9. Structure IV ventricle as built covering IV ventricle. 10. Cavity bubbles whose brain is a 4th ventricle? 11. What are vital centers within the medulla oblongata? 4.3. Practical tasks pertaining to the topic and to be completed during the class: Show location on the skull of the medulla oblongata, the bridge. Demonstrate isolated on wet preparation of the foreign structure of the medulla oblongata, the bridge. Show space projection cranial nuclei of the bridge. Show location projection cranial nuclei of the medulla oblongata. In wet isolated anatomical lesions show drug IV ventricle, plumbing midbrain. The content of the topic: Fourth Ventricle The fourth ventricle is a tent-shaped cavity filled with cerebrospinal fluid. It is situated anterior to the cerebellum and posterior to the pons and the superior half of the medulla oblongata. It is lined with ependyma and is continuous above with the cerebral aqueduct of the midbrain and below with the central canal of the medulla oblongata and the spinal cord. The fourth ventricle possesses lateral boundaries, a roof, and a rhomboid-shaped floor. Lateral Boundaries The caudal part of each lateral boundary is formed by the inferior cerebellar peduncle. The cranial part of each lateral boundary is formed by the superior cerebellar peduncle. Roof or Posterior Wall The tent-shaped roof projects into the cerebellum. The superior part is formed by the medial borders of the two superior cerebellar peduncles and a connecting sheet of white matter called the superior medullary velum. The inferior part of the roof is formed by the inferior medullary velum, which consists of a thin sheet devoid of nervous tissue and formed by the ventricular ependyma and its posterior covering of pia mater. This part of the roof is pierced in the midline by a large aperture, the median aperture or foramen of Magendie. Lateral recesses extend laterally around the sides of the medulla and open anteriorly as the lateral openings of the fourth ventricle, or the foramina of Luschka. Thus, the cavity of the fourth ventricle communicates with the subarachnoid space through a single median opening and two lateral apertures. These important openings permit the cerebrospinal fluid to flow from the ventricular system into the subarachnoid space. Floor or Rhomboid Fossa The diamond-shaped floor is formed by the posterior surface of the pons and the cranial half of the medulla oblongata. The floor is divided into symmetrical halves by the median sulcus. On each side of this sulcus, there is an elevation, the medial eminence, which is bounded laterally by another sulcus, the sulcus limitans. Lateral to the sulcus limitans, there is an area known as the vestibular area. The vestibular nuclei lie beneath the vestibular area. The facial colliculus is a slight swelling at the inferior end of the medial eminence that is produced by the fibers from the motor nucleus of the facial nerve looping over the abducens nucleus. At the superior end of the sulcus limitans, there is a bluish-gray area, produced by a cluster of nerve cells containing melanin pigment; the cluster of cells is called the substantia ferruginea. Strands of nerve fibers, the stria medullaris, derived from the arcuate nuclei, emerge from the median sulcus and pass laterally over the medial eminence and the vestibular area and enter the inferior cerebellar peduncle to reach the cerebellum. Inferior to the stria medullaris, the following features should be recognized in the floor of the ventricle. The most medial is the hypoglossal triangle, which indicates the position of the underlying hypoglossal nucleus. Lateral to this is the vagal triangle, beneath which lies the dorsal motor nucleus of the vagus. The area postrema is a narrow area between the vagal triangle and the lateral margin of the ventricle, just rostral to the opening into the central canal. The inferior part of the vestibular area also lies lateral to the vagal triangle. Choroid Plexus of the Fourth Ventricle The choroid plexus has a T shape; the vertical part of the T is double. It is suspended from the inferior half of the roof of the ventricle and is formed from the highly vascular tela choroidea. The tela choroidea is a two-layered fold of pia mater that projects through the roof of the ventricle and is covered by ependyma. The blood supply to the plexus is from the posterior inferior cerebellar arteries. The function of the choroid plexus is to produce cerebrospinal fluid.

Materials for self-check. A. Tasks for self- check: Draw a projection cranial nerve nuclei in diamond-shaped hole. B. Tasks for self- check: 1.On the examination of a woman who had a brain injury the bleeding in the area of the triangle vagus nerve rhomboid fossa was found. Nuclei of which pairs of cranial nerves are projected in this part of the rhomboid fossa? A.The nuclei of the X pair of cranial nerves B.The nuclei of I, II pairs of cranial nerves C.The nuclei of the III, IV, V pair of cranial nerves D.The nuclei of IV, V, VI pairs of cranial nerves E.The nuclei of the VII pair of cranial nerves

2.On the examination of a man who had a brain injury the violation of the integrity of brain structures that limit the diamond-shaped hole that shape it from both sides above was found. Which structures of the brain are damaged? A.Superior medullary velum B.The lower legs of the cerebellum C.The upper legs of the cerebellum D.Inferior medullary velum 3.On the examination of a man who had a brain injury the foreign body in the area of the triangle hypoglossal nerve was detected. In this triangle such nuclei projected: A.The nuclei of the IV, V, VI pairs of cranial nerves B.The nuclei of I, II pairs of cranial nerves C.The nuclei of the III, IV, V pairs of cranial nerves D.The nuclei of the VII pair of cranial nerves E.The nuclei of the X pair of cranial nerves 4.In the formation of the walls of the fourth ventricle the Superior medullary velum takes part. It is stretched between: A.crurasuperioris cerebelli B.cruribus cerebellum C.Mediocris posterior pedes. D.Folia cerebellum. E.Cerebelli vermis etexiguo. 5.At postmortem brain research is necessary to determine the measure between Medulla oblongata and pons on the dorsal side A.Ingeniumnudaveris B.The roots of language-pharyngeal nerves. C.Roots additional nerves. D.Hypoglossal nerve roots. E.I par nervorumspinalium radices. 6.In the lower triangle of rhomboid fossa is projected: A.The nuclei IX, X, XI, XII pairs of cranial nerves B.The nuclei I, II, III pairs of cranial nerves C.The nuclei III, IV, V pairs of cranial nerves D.The nuclei IV, V, VI pairs of cranial nerves E.The nuclei VI, VII, VIII pairs of cranial nerves 7.In the lower triangle of rhomboid fossa is projected: A.The nuclei V, VI, VII, VIII pairs of cranial nerves B.The nuclei I, II, III pairs of cranial nerves C.The nuclei III, IV, V pairs of cranial nerves D.The nuclei IV, V, VI pairs of cranial nerves E.The nuclei IX, X, XI, XII pairs of cranial nerves 8.Rhomboid fossa is divided into the left and right triangles: A.Median furrow B.Front of the median slit C.Retro-olivary groove D.Preolivary groove E.Cerebral stripes 9.Rhomboid fossa is divided into the upper and lower triangle: A.Cerebral stripes B.Posterior median sulcus C.Front of the median slit D.Retro-olivary groove E.Preolivary groove 10.IV ventricle is the residue of the cavity of: A.Diamond-shaped vesicles B.Anterior cerebral vesicles C.Posterior cerebral vesicles D.Middle cerebral vesicles E.All of the above listed brain vesicles

Topic 25. Midbrain. 1. Relevance of the topic: If the damage midbrain there are complications that lead to disruption of motor reactions of the patient, visual, auditory. 2. The specific aims: To explain the structure of the brain stem and midbrain location. Analyze: elements of the external structure of the midbrain; - The internal structure of the midbrain; - Pathways midbrain. 3. Basic knowledge and skills necessary to study the topic (inter- disciplinary integration).

Disciplines Know Be able 1) interim Distribution of the nervous Show the location of the main discipline system to the central and elements of the central Biology peripheral. Features nervous system mammalian CNS Histology The structure of gray and Distinguish between white and white matter of the gray matter in the midbrain midbrain histological preparations 2) Courses are provided: Normal and Pathological Physiology, topographical and pathological anatomy, surgery, nerve disease. 3) Intersubject Knowing the structure of Show middle cranial fossa. integration -rozdil the middle cranial fossa. Show on the preparation of the "Osteology" Know the blood supply to internal carotid and vertebral Section the brain and spinal cord. artery. "Angiology"

4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class. MESENCEPHALON Midbrain Sulcus nervi oculomotorii Furrow oculomotor nerve Pedunculus cerebri brain stem Sulcus lateralis mesencephali Lateral sulcus midbrain Tegmentum mesencephali The roof of the midbrain Pedunculus cerebellaris superior The upper cerebellar legs Lamina tecti plate roof Brachium colliculi inferioris Handle lower mound Brachium colliculi superioris Handle upper mound Colliculus inferior Lower hill Colliculus superior Upper hill Pedunculus cerebri Actually brain stem Basis pedunculi Base legs Crus cerebri brain stem Tractus pyramidalis pyramidal way Fibrae corticospinales Cortical-spinal fibers Fibrae corticonucleares Cortex-core fiber Tractus corticopontinus Bridge cortical fiber Fibrae frontopontinae Fronto-bridge fiber Fibrae occipitopontinae Neck-bridge fiber Fibrae parietopontinae Thyme-bridge fiber Fibrae temporopontinae Roofing-bridge fiber Fibrae corticoreticulares Cortex-fiber mesh Substantia nigra Black stuff Tegmentum mesencephali The roof of the midbrain Substantia alba White matter 4.2. Theoretical questions for the class: 1. Derivative which is a think bubble structure, belonging to the midbrain? 2. What are the patterns seen in the context middle frontal brain? 3. Nuclei of cranial nerves which are located within the mid-brain, and what is their topography? 4. Where to go from the brain III, IV pairs of cranial nerves? 5. The oral derivative which is a think bubble water pipe and that the brain it connects brain cavity? 4.3. Practical tasks pertaining to the topic and to be completed during the class: 1.Show the skull projection location of the midbrain. 2.Demonstrate the wet preparation of the foreign structure midbrain. 3.On cross-section to show the red nucleus, white matter, water cord. 4.Demonstrate communication plumbing brain III, IV ventricles brain. 5.In isolated brain preparation to be able to display the anatomical midbrain lesions (tire, brain stem, plumbing brain). The content of the topic: The midbrain measures about 0.8 inch (2 cm) in length and connects the pons and cerebellum with the forebrain. Its long axis inclines anteriorly as it ascends through the opening in the tentorium cerebelli. The midbrain is traversed by a narrow channel, the cerebral aqueduct, which is filled with cerebrospinal fluid. On the posterior surface are four colliculi (corpora quadrigemina). These are rounded eminences that are divided into superior and inferior pairs by a vertical and a transverse groove. The superior colliculi are centers for visual reflexes, and the inferior colliculi are lower auditory centers. In the midline below the inferior colliculi, the trochlear nerves emerge. These are small-diameter nerves that wind around the lateral aspect of the midbrain to enter the lateral wall of the cavernous sinus. On the lateral aspect of the midbrain, the superior and inferior brachia ascend in an anterolateral direction. The superior brachium passes from the superior colliculus to the lateral geniculate body and the optic tract. The inferior brachium connects the inferior colliculus to the medial geniculate body. On the anterior aspect of the midbrain, there is a deep depression in the midline, the interpeduncular fossa, which is bounded on either side by the crus cerebri. Many small blood vessels perforate the floor of the interpeduncular fossa, and this region is termed the posterior perforated substance. The oculomotor nerve emerges from a groove on the medial side of the cms cerebri and passes forward in the lateral wall of the cavernous sinus. INTERNAL STRUCTURE OF THE MIDBRAIN The midbrain comprises two lateral halves, called the cerebral peduncles; each of these is divided into an anterior part, the crus cerebri, and a posterior part, the tegmentum, by a pigmented band of gray matter, the substantia nigra. The narrow cavity of the midbrain is the cerebral aqueduct, which connects the third and fourth ventricles. The tectum is the part of the midbrain posterior to the cerebral aqueduct; it has four small surface swellings referred to previously; these are the two superior and two inferior colliculi. The cerebral aqueduct is lined by ependyma and is surrounded by the central gray matter. On transverse sections of the midbrain, the interpeduncular fossa can be seen to separate the crura cerebri, whereas the tegmentum is continuous across the median plane. Transverse Section of the Midbrain at the Level of the Inferior Colliculi The inferior colliculus, consisting of a large nucleus of gray matter, lies beneath the corresponding surface elevation and forms part of the auditory pathway. It receives many of the terminal fibers of the lateral lemniscus. The pathway then continues through the inferior brachium to the medial geniculate body. The trochlear nucleus is situated in the central gray matter close to the median plane just posterior to the medial longitudinal fasciculus. The emerging fibers of the trochlear nucleus pass laterally and posteriorly around the central gray matter and leave the midbrain just below the inferior colliculi. The fibers of the trochlear nerve now decussate completely in the superior medullary velum. The mesencephalic nuclei of the trigeminal nerve are lateral to the cerebral aqueduct. The decussation of the superior cerebellar peduncles occupies the central part of the tegmentum anterior to the cerebral aqueduct. The reticular formation is smaller than that of the pons and is situated lateral to the decussation. The medial lemniscus ascends posterior to the substantia nigra; the spinal and trigeminal lemnisci are situated lateral to the medial lemniscus. The lateral lemniscus is located posterior to the trigeminal lemniscus. The substantia nigra is a large motor nucleus situated between the tegmentum and the crus cerebri and is found throughout the midbrain. The nucleus is composed of medium-size multipolar neurons that possess inclusion granules of melanin pigment within their cytoplasm. The substantia nigra is concerned with muscle tone and is connected to the cerebral cortex, spinal cord, hypothalamus, and basal nuclei. The crus cerebri contains important descending tracts and is separated from the tegmentum by the substantia nigra. The corticospinal and corticonuclear fibers occupy the middle two-thirds of the crus. The frontopontine fibers occupy the medial part of the crus, and the temporopontine fibers occupy the lateral part of the crus. These descending tracts connect the cerebral cortex to the anterior gray column cells of the spinal cord, the cranial nerve nuclei, the pons, and the cerebellum. Transverse Section of the Midbrain at the Level of the Superior Colliculi The superior colliculus, a large nucleus of gray matter that lies beneath the corresponding surface elevation, forms part of the visual reflexes. It is connected to the lateral geniculate body by the superior brachium. It receives afferent fibers from the optic nerve, the visual cortex, and the spinotectal tract. The efferent fibers form the tectospinal and tectobulbar tracts, which are probably responsible for the reflex movements of the eyes, head, and neck in response to visual stimuli. The afferent pathway for the light reflex ends in the pretectal nucleus. This is a small group of neurons situated close to the lateral part of the superior colliculus. After relaying in the pretectal nucleus, the fibers pass to the parasympathetic nucleus of the oculomotor nerve (Edinger-Westphal nucleus). The emerging fibers then pass to the oculomotor nerve. The oculomotor nucleus is situated in the central gray matter close to the median plane, just posterior to the medial longitudinal fasciculus. The fibers of the oculomotor nucleus pass anteriorly through the red nucleus to emerge on the medial side of the crus cerebri in the interpeduncular fossa. The nucleus of the oculomotor nerve is divisible into a number of cell groups. The medial, spinal, and trigeminal lemnisci form a curved band posterior to the substantia nigra, but the lateral lemniscus does not extend superiorly to this level. The red nucleus is a rounded mass of gray matter situated between the cerebral aqueduct and the substantia nigra. Its reddish hue, seen in fresh specimens, is due to its vascularity and the presence of an iron-containing pigment in the cytoplasm of many of its neurons. Afferent fibers reach the red nucleus from (1) the cerebral cortex through the corticospinal fibers, (2) the cerebellum through the superior cerebellar peduncle, and (3) the Ientiform nucleus, subthalamic and hypothalamic nuclei, substantia nigra, and spinal cord. Efferent fibers leave the red nucleus and pass to (1) the spinal cord through the rubrospinal tract (as this tract descends, it decussates), (2) the reticular formation through the rubroreticular tract, (3) the thalamus, and (4) the substantia nigra. The reticular formation is situated in the tegmentum lateral and posterior to the red nucleus. The crus cerebri contains the identical important descending tracts, the corticospinal, corticonuclear, and corticopontine fibers, that are present at the level of the inferior colliculus. Cerebral Aqueduct (Aqueduct of Sylvius) The cerebral aqueduct, a narrow channel about 3/4 of an inch (1.8 cm) long, connects the third ventricle with the fourth ventricle. It is lined with ependyma and is surrounded by a layer of gray matter called the central gray. The direction of flow of cerebrospinal fluid is from the third to the fourth ventricle. There is no choroid plexus in the cerebral aqueduct.

Materials for self-check. A. Tasks for self- check: Draw midbrain nuclei, gray and white matter. B. Choose the correct answer: 1.During the appendectomy anesthesiologist noticed the patient has no pupillary reflex as a result of an overdose of anaesthetic. Which structure of the brainstem involved in the process? A.Midbrain. B.cerebrum. C.Interim brain. D.Medulla oblongata. E.Rear brain. 2.To the neurosurgical department was admitted a patient in a coma (disturbance of consciousness and lack of purposeful reactions to any stimuli). When examining doctor found that dysfunction of the cerebral cortex was caused by the brainstem neuronal network, which supported the activity of the cerebral cortex. What impressed brain structure? A.Reticular formation. B.Basal nucleus. C.The nuclei of the cerebellum. D.Caudate nucleus. E.The nuclei of the hypothalamus. 3.As a result of a damage of a.cerebri posteriores often a so-called red nucleus syndrome occurs - paralysis of the oculomotor nerve on the side of the pathological source, trembling limbs on the opposite side. What part of the brain is affected? A.Mesencephalon. B.Thalamus. C.Metathalamus. D.Epithalamus. E.Hypothalamus. 4. The patient with an ophthalmoplegic form of botulism occurs a midbrain lesions, clinical manifestations of which are diplopia, paralysis of accommodation, ptosis, expansion and deformation of the pupils, the absence of reaction of pupils to light. Damage of which midbrain nuclei leads to such clinical symptoms? A.Nuclei oculomotor nerve, vagus B.Superior colliculi C.Inferior colliculi D.Red nucleus. E.Substantia nigra 5.The patient has a midbrain tumor associated with violation of embryonic development. Out of what vesicle does a midbrain develop? A.3rd. B.1st. C.2nd. D.4th. E.5th 6.As a result of hemorrhage damage to brain structures is observed that relate to the midbrain. Which of these structures in NOT located in the midbrain? A.subcortical center of smell. B.subcortical center of hearing. C.subcortical center of vision. D.pathways linking the cortex of the forebrain to the spinal cord. E.nuclei of the oculomotor nerves. 7.Patient has a disorder in a liquor flow at the midbrain. What are the cavities of the midbrain? A.Aqueduct. B.IV ventricle. C.III ventricle. D.lateral ventricle. E.Central Canal. 8.After an infection a patient is left with a damaged midbrain nuclei. Which of the structures in located outside of the midbrain? A.Nucl. tracti mesencephalici n. trigemini. B.Nucl. n. oculomotorii. C.Nucl. accessorius. D.Nucl. n. trochlearis. 9.The patient has a violationof the reflex reaction to sudden visual stimuli. Subcortical centers of vision of the midbrain laid down in: A.Colliculi superiores. B.Corpus geniculatum laterale. C.Brachium colliculi inferiores. D.Brachium colliculi superiores. E.Colliculi inferiores. 10.Reflex center for various movements that have arisen under the influence of visual and auditory stimuli are: A.inferior colliculi and superior colliculi of the tectum B.Red nucleus. C.Substantia nigra. D.The nuclei of the cranial nerves. E.Reticular formation.

Topic 26. Diencephalon, the third ventricle. 1. Relevance of the topic: Knowledge of the topography, the structure of all departments of an intermediate brain will help in determining the correct diagnosis of the patient, because the brain lesions of intermediate appear serious disorders of various kinds of sensitivity and autonomic function disorder. 2. The specific aims: Analyze the structure of the brain stem and limits the location of the intermediate brain. Explain: - included in the intermediate brain; - Part of which is the visual area of the hill; - What external and internal structure of the thalamus; - Which represents a functionally thalamus; - III ventricle structure and because it connects with other ventricles of the brain. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration).

Disciplines Know Be able 1) interim discipline The development of the Show the location of the main Biology nervous system in mammals. parts of the central nervous Features affection system and diencephalon. Histology Thediencephalon structure. of the nucleus of To be able to distinguish the diencephalon between white and gray matter 2) Courses are provided: Normal and Pathological of Physiology, the diencephalon. topographical and pathological anatomy, surgery, nerve disease. 3) Intersubject Know the boundaries of the To be able to show the skull integration -rozdil middle cranial fossa, pituitary projection location "Osteology" fossa. diencephalon. section: Know the features of blood To be able to show on wet "Angiology" supply to the brain. preparation of the internal carotid and vertebral artery.

4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class. DIENCEPHALON Interim brain Trigonum habenulare Triangle leash Thalamus Thalamus Tuberculum anterius thalami Front mound thalamus Pulvinar thalami Pillow thalamus Subthalamus subthalamic Metathalamus Metatalamus Соrpus geniculatum laterale Lateral body kolinchaste Hypothalamus The hypothalamus Соrpus mamillare papillary body Pars nervosa The nervous part Chiasma opticum chiasm Tractus opticus Visual way Radix lateralis lateral roots Radix medialis The medial root Ventriculus tertius The third ventricle Foramen interventriculare interventricular hole Tela choroidea vascular layer

4.2. Theoretical questions for the class: 1. Name the show and the three main parts of the diencephalon in different series anatomical preparations brain. 2. Name the show and the thalamus, the relief of its external structure, the kernel tell its function. 3. Calling and show parts of the hypothalamus, tell them to function. 4. Name and show neurosecretory nuclei of the hypothalamus, talk about their relationship with the pituitary gland. 5. Name the show and intermediate parts of the brain that consists of six walls of the third ventricle. 6. Name the show and relations with third ventricle and fourth ventricle side. 4.3. Practical tasks pertaining to the topic and to be completed during the class: 1.Show the location of the main parts of NS. 2.Show location diencephalon. 3.Show white and gray matter of the diencephalon. 4.Show the skull projection location diencephalon. 5. Show on wet preparation of the internal carotid and vertebral artery. The content of the topic: Interim brain SUBDIVISIONS OF THE CEREBRUM The cerebrum is the largest part of the brain and is situated in the anterior and middle cranial fossae of the skull occupying the whole concavity of the vault of the skull. It may be divided into two parts: the diencephalon, which forms the central core, and the telencephalon, which forms the cerebral hemispheres. DIENCEPHALON The diencephalon consists of the third ventricle and the structures that form its boundaries. It extends posteriorly to the point where the third ventricle becomes continuous with the cerebral aqueduct and anteriorly as far as the interventricular foramina. Thus the diencephalon is a midline structure with symmetrical right and left halves. Obviously, these subdivisions of the brain are made for convenience, and from a functional point of view, nerve fibers freely cross the boundaries. Gross Features The inferior surface of the diencephalon is the only area exposed to the surface in the intact brain. It is formed by hypothalamic and other structures, which include, from anterior to posterior, the optic chiasma, with the optic tract on either side; the infundibulum, with the tuber cinereum; and the mammillary bodies. The superior surface of the diencephalon is concealed by the fornix, which is a thick bundle of fibers that originates in the hippocampus of the temporal lobe and arches posteriorly over the thalamus to join the mammillary body. The actual superior wall of the diencephalon is formed by the roof of the third ventricle. This consists of a layer of ependyma, which is continuous with the rest of the ependymal lining of the third ventricle. It is covered superiorly by a vascular fold of pia mater, called the tela choroidea of the third ventricle. From the roof of the third ventricle, a pair of vascular processes, the choroid plexuses of the third ventricle, project downward from the midline into the cavity of the third ventricle. The lateral surface of the diencephalon is bounded by the internal capsule of white matter and consists of nerve fibers that connect the cerebral cortex with other parts of the brainstem and spinal cord. Since the diencephalon is divided into symmetrical halves by the slitlike third ventricle, it also has a medial surface. The medial surface of the diencephalon (i.e., the lateral wall of the third ventricle) is formed in its superior part by the medial surface of the thalamus and in its inferior part by the hypothalamus. These two areas are separated from one another by a shallow sulcus, the hypothalamic sulcus. A bundle of nerve fibers, which are afferent fibers to the habenular nucleus, forms a ridge along the superior margin of the medial surface of the diencephalon and is called the stria medullaris thalami. The diencephalon can be divided into four major parts: (1) the thalamus, (2) the subthalamus, (3) the epithalamus, and (4) the hypothalamus. Thalamus The thalamus is a large ovoid mass of gray matter that forms the major part of the diencephalon. It is a region of great functional importance and serves as a cell station to all the main sensory systems (except the olfactory pathway). The thalamus is situated on each side of the third ventricle. The anterior end of the thalamus is narrow and rounded and forms the posterior boundary of the interventricular foramen. The posterior end is expanded to form the pulvinar, which overhangs the superior colliculus and the superior brachium. The lateral geniculate body forms a small elevation on the under aspect of the lateral portion of the pulvinar. The superior surface of the thalamus is covered medially by the tela choroidea and the fornix, and laterally, it is covered by ependyma and forms part of the floor of the lateral ventricle; the lateral part is partially hidden by the choroid plexus of the lateral ventricle. The inferior surface is continuous with the tegmentum of the midbrain. The medial surface of the thalamus forms the superior part of the lateral wall of the third ventricle and is usually connected to the opposite thalamus by a band of gray matter, the interthalamic connection (interthalamic adhesion). The lateral surface of the thalamus is separated from the lentiform nucleus by the very important band of white matter called the internal capsule. The thalamus is a very important cell station and receives the main sensory tracts (except the olfactory pathway). It should be regarded as a station where much of the information is integrated and relayed to the cerebral cortex and many other subcortical regions. It also plays a key role in the integration of visceral and somatic functions. Subthalamus The subthalamus lies inferior to the thalamus and, therefore, is situated between the thalamus and the tegmentum of the midbrain; craniomedially, it is related to the hypothalamus. The structure of the subthalamus is extremely complex, and only a brief description is given here. Among the collections of nerve cells found in the subthalamus are the cranial ends of the red nuclei and the substantia nigra. The subthalamic nucleus has the shape of a biconvex lens. The nucleus has important connections with the corpus striatum; as a result, it is involved in the control of muscle activity. The subthalamus also contains many important tracts that pass up from the tegmentum to the thalamic nuclei; the cranial ends of the medial, spinal, and trigeminal lemnisci are examples. Epithalamus The epithalamus consists of the habenular nuclei and their connections and the pineal gland. Habenular Nucleus The habenular nucleus is a small group of neurons situated just medial to the posterior surface of the thalamus. Afferent fibers are received from the amygdaloid nucleus in the temporal lobe through the stria medullaris thalami; other fibers pass from the hippocampal formation through the fornix. Some of the fibers of the stria medullaris thalami cross the midline and reach the habenular nucleus of the opposite side; these latter fibers form the habenular commissure. Axons from the habenular nucleus pass to the interpeduncular nucleus in the roof of the interpeduncular fossa, the tectum of the midbrain, the thalamus, and the reticular formation of the midbrain. The habenular nucleus is believed to be a center for integration of olfactory, visceral, and somatic afferent pathways. Pineal Gland (Body) The pineal gland is a small, conical structure that is attached by the pineal stalk to the diencephalon. It projects backward so that it lies posterior to the midbrain. The base of the pineal stalk possesses a recess that is continuous with the cavity of the third ventricle. The superior part of the base of the stalk contains the habenular commissure; the inferior part of the base of the stalk contains the posterior commissure. On microscopic section, the pineal gland is seen to be incompletely divided into lobules by connective tissue septa that extend into the substance of the gland from the capsule. Two types of cells are found in the gland, the pinealocytes and the glial cells. Concretions of calcified material called brain sand progressively accumulate within the pineal gland with age. The pineal gland possesses no nerve cells, but adrenergic sympathetic fibers derived from the superior cervical sympathetic ganglia enter the gland and run in association with the blood vessels and the pinealocytes. Functions of the Pineal Gland The pineal gland, once thought to be of little importance, is now recognized as an endocrine gland capable of influencing the activities of the pituitary gland, the islets of Langerhans of the pancreas, the parathyroids, the adrenals, and the gonads. The pineal secretions, produced by the pinealocytes, reach their target organs via the bloodstream or through the cerebrospinal fluid. Their actions are mainly inhibitory and either directly inhibit the production of hormones or indirectly inhibit the secretion of releasing factors by the hypothalamus. It is interesting to note that the pineal gland does not possess a blood-brain barrier. Animal experiments showed that pineal activity exhibits a circadian rhythm that is influenced by light. The gland has been found to be most active during darkness. The probable nervous pathway from the retina runs to the suprachias- matic nucleus of the hypothalamus, then to the tegmentum of the midbrain, and then to the pineal gland to stimulate its secretions. The latter part of this pathway may include the reticulospinal tract, the sympathetic outflow of the thoracic part of the spinal cord, and the superior cervical sympathetic ganglion and postganglionic nerve fibers that travel to the pineal gland on blood vessels. Melatonin and the enzymes needed for its production are present in high concentrations within the pineal gland. Melatonin and other substances are released into the blood or into the cerebrospinal fluid of the third ventricle where they pass to the anterior lobe of the pituitary gland and inhibit the release of the gonadotrophic hormone. In humans, as in animals, the plasma melatonin level rises in darkness and falls during the day. It would appear that the pineal gland plays an important role in the regulation of reproductive function. Hypothalamus The hypothalamus is that part of the diencephalon that extends from the region of the optic chiasma to the caudal border of the mammillary bodies. It lies below the hypothalamic sulcus on the lateral wall of the third ventricle. It is thus seen that anatomically the hypothalamus is a relatively small area of the brain that is strategically well placed close to the limbic system, the thalamus, the ascending and descending tracts, and the hypophysis. Microscopically, the hypothalamus is composed of small nerve cells that are arranged in groups or nuclei. Physiologically, there is hardly any activity in the body that is not influenced by the hypothalamus. The hypothalamus controls and integrates the functions of the autonomic nervous system and the endocrine systems and plays a vital role in maintaining body homeostasis. It is involved in such activities as regulation of body temperature, body fluids, drives to eat and drink, sexual behavior, and emotion. Relations of the Hypothalamus Anterior to the hypothalamus is an area that extends forward from the optic chiasma to the lamina terminalis and the anterior commissure; it is referred to as the preoptic area. Caudally, the hypothalamus merges into the tegmentum of the midbrain. The thalamus lies superior to the hypothalamus, and the subthalamic region lies inferolaterally to the hypothalamus. When observed from below, the hypothalamus is seen to be related to the following structures, from anterior to posterior: (1) the optic chiasma, (2) the tuber cinereum and the infundibulum, and (3) the mammillary bodies. Optic Chiasma The optic chiasma is a flattened bundle of nerve fibers situated at the junction of the anterior wall and floor of the third ventricle. The superior surface is attached to the lamina terminalis, and interiorly, it is related to the hypophysis cerebri, from which it is separated by the diaphragma sellae. The anterolateral corners of the chiasma are continuous with the optic nerves, and the posterolateral corners are continuous with the optic tracts. A small recess, the optic recess of the third ventricle, lies on its superior surface. It is important to remember that the fibers originating from the nasal half of each retina cross the median plane at the chiasma to enter the optic tract of the opposite side. Tuber Cinereum The tuber cinereum is a convex mass of gray matter, as seen from the inferior surface. It is continuous inferiorly with the infundibulum. The infundibulum is hollow and becomes continuous with the posterior lobe of the hypophysis cerebri. The median eminence is a raised part of the tuber cinereum to which is attached the infundibulum. The median eminence, the infundibulum, and the posterior lobe (pars nervosa) of the hypophysis cerebri together form the neurohypophysis. Mammillary Bodies The mammillary bodies are two small hemispherical bodies situated side by side posterior to the tuber cinereum. They possess a central core of gray matter in- vested by a capsule of myelinated nerve fibers. Posterior to the mammillary bodies lies an area of the brain that is pierced by a number of small apertures and is called the posterior perforated substance. These apertures transmit the central branches of the posterior cerebral arteries. Third Ventricle The third ventricle, which is derived from the forebrain vesicle, is a slitlike cleft between the two thalami. It communicates anteriorly with the lateral ventricles through the interventricular foramina (foramina of Monro), and it communicates posteriorly with the fourth ventricle through the cerebral aqueduct. The third ventricle has anterior, posterior, lateral, superior, and inferior walls and is lined with ependyma. The anterior wall is formed by a thin sheet of gray matter, the lamina terminalis, across which runs the anterior commissure. The anterior commissure is a round bundle of nerve fibers that are situated anterior to the anterior columns of the fornix; they connect the right and left temporal lobes. The posterior wall is formed by the opening into the cerebral aqueduct. Superior to this opening is the small posterior commissure. Superior to the commissure is the pineal recess, which projects into the stalk of the pineal body. Superior to the pineal recess is the small habenular commissure. The lateral wall is formed by the medial surface of the thalamus superiorly and the hypothalamus inferiorly. These two structures are separated by the hypothalamic sulcus. The lateral wall is limited superiorly by the stria medullaris thalami. The lateral walls are joined by the interthalamic connection. The superior wall or roof is formed by a layer of ependyma that is continuous with the lining of the ventricle. Superior to this layer is a two-layered fold of pia mater called the tela choroidea of the third ventricle. The vascular tela choroidea projects downward on each side of the midline, invaginating the ependymal roof to form the choroid plexuses of the third ventricle. Within the tela choroidea lie the internal cerebral veins. Superiorly, the roof of the ventricle is related to the fornix and the corpus callosum. The inferior wall or floor is formed by the optic chiasma the tuber cinereum, the infundibulum, with its funnel-shaped recess, and the mammillary bodies. The hypophysis is attached to the infundibulum. Posterior to these structures lies the tegmentum of the cerebral peduncles.

Materials for self-check. A. Tasks for self-check: the tables to designate intermediate parts of the brain. B. Choose the correct answer: 1.Patient notes the loss of all kinds of sensitivity (surface and deep) on one side of the body, forced laughter and crying, upset autonomic functions. Which part of brain is injured? A.Diencephalon B.Mesencephalon. C.Pons. D.Medulla oblongata. E.Telencephalon. 2.A 3 years old boy has a premature puberty. Which part of brain is injured? A.Diencephalon B.Mesencephalon. C.Pons. D.Medulla oblongata. E.Telencephalon. 3.The patient during the examination of the brain using MRI revealed markedly dilated lateral and third ventricles. The doctor diagnosed blockade of cerebrospinal fluid pathways. Point the level of occlusion: A.Cerebral aqueduct B.interventricular hole C.median aperture of the fourth ventricle D.lateral aperture of the fourth ventricle E.granulationes arachnoidae 4.A patient with a damaged cord intermediate breach hearing. What are the core while damaged? A.medial geniculate body B.lateral geniculate body C.nucleus ruber D.Anterior nucleus of the hypothalamus E.Posterior ventral nucleus 5.A 50 years old patient was diagnosed with a brain tumor in the visual area of the hypothalamus. There is an elevated levels of vasopressin in the blood of patient. Which nucleus of the hypothalamus produces this hormone? A.Nucl. supraopticus B.Nucl. preopticus C.Nucl.paraventricularis D.Nucl.corporis mamillaris E.Nucl.in undibularis 6.The patient hypothalamic-pituitary syndrome (Babinsky-Fröhlich), fat deposits in the shoulder belt, breasts, loss of secondary sexual characteristics, susceptibility to hypothermia. Which department applies to the hypothalamus of the brain? A.Diencephalon B.Mesencephalon. C.Pons. D.Medulla oblongata. E.Telencephalon. 7.A patient was diagnosed with malignant exophthalmos caused by excessive secretion of pituitary thyroid stimulating hormone. Which department diencephalon does pituitary belong to? A.Hypothalamus B.Mesencephalon C.Thalamus D.Metathalamus E.Epithalamus 8.The patient was diagnosed with bulimia -- increased hunger. Has been detected the injure of the hypothalamic receptor site that signals to the brain about accumulation of carbohydrates in the blood. What brain is affected? A.Diencephalon B.Medulla oblongata C.Mesencephalon D.Pons. E.Medulla oblongata 9.Because of injury a.cerebri posteriores observed symptoms of nuclei oculomotor nerve (Parinaud's Syndrome). What wall of the III ventricle forms comissura cerebri posterior? A.Posterior B.Inferior C.Superior D.Anterior E.Lateralis 10.The patient in '50 revealed thalamic syndrome, symptoms of which are an intense pain of the half of the body, "thalamic hand", hyperkinetic disorder. Sometimes these manifestations are joined with smell disorder, violent laughter, and crying. What part of the brain is functionally damaged? A.Thalamus B.Metathalamus C.Epithalamus D.Hypothalamus E.Mesencephalon

Theme 27. External structure of cerebral hemispheres. 1. Relevance of the topic: Knowledge of the topography, the structure of the brain will help in determining the correct diagnosis of the patient, since the defeat of the brain there are serious disturbances to the loss of sensitivity of different types of motor responses. Will help be prevented inflammation and traumatic brain damage. 2. The specific aims: Analyze the structure of the forebrain, the particles, the poles and the surface of the forebrain. Explain: - The limits of the cerebral hemispheres; the boundaries between the particles of the forebrain; sulcus and frontal lobe gyrus; sulcus and parietal lobe gyrus; temporal gyrus and sulcus share; and gyrus and sulcus of the occipital lobe. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). Disciplines Know Be able 1) interim discipline Distribution of the nervous system Show the location of the Biology to the central and peripheral. main elements of the CNS. Features of the central nervous system of mammals. 2) Courses are provided: Normal and Pathological Physiology topographical and pathological anatomy, surgery, nerve disease. 3) Interdiscipline Knowing the structure of the Show limits cranial fossa. integration - cranial fossa. The blood supply of Show the internal carotid the "Osteology" to the brain. artery. "Angiology" 4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class.

TELENCEPHALON; CEREBRUM cerebrum

Hemispherium cerebri The cerebral hemispheres

Gyri cerebri Gyrus of the brain

Lobi cerebri shares brain

Sulci cerebri Furrows brain

Lobus frontalis frontal lobe

Lobus parietalis parietal lobe Lobus temporalis temporal lobe

Lobus occipitalis occipital lobe

Lobus insularis Islet 4.2. Theoretical questions for the class: 1. Derivative which is a think bubble hemisphere of the brain? 2. Why of the cerebral hemisphere separated from one another? 3. What are the surface and edges are distinguished in each hemisphere of the brain? 4. Part of each hemisphere of the brain? 5. How many fractions divided each hemisphere? 6. What is called the fifth section of the hemisphere (hidden) and the fate of the brain where it posted? 7. What is the fate of borders between the brain? 8. What distinguished within gyrus frontal sulci fate and that they are separate? 9. What are the branches away from the lateral sulcus (fissure) in the brain and which parts they divide the lower frontal gyrus? 10. What are the limits and show the parietal lobe. 11. What gyrus distinguished within the parietal lobe sulci and what they are separate? 12. What gyrus is completed by the end of the lateral and posterior superior temporal end furrow? 13. Which lobe gyrus these two related? 14. What distinguished gyrus in the temporal lobe sulci and that they are separate? 15. What groups are divided gyrus and sulcus occipital lobe? 16. What fate gyrus and sulcus differ on the medial surface of the hemispheres? 4.3. Practical tasks pertaining to the topic and to be completed during the class: In preparations demonstrate cerebral hemisphere, their surfaces, edges and boundaries between particles last. On the surface verhnobichniy demonstrate the central and lateral grooves brain. Showcasing the furrows and convolutions of the frontal lobe. Showcasing the grooves and wedges parietal lobe. Showcasing temporal gyrus and sulcus share. Showcasing gyrus and sulcus of the occipital lobe. Showcasing the island, its grooves and convolutions. The content of the topic: GENERAL APPEARANCE OF THE CEREBRAL HEMISPHERES The cerebral hemispheres are the largest part of the brain and are separated by a deep midline sagittal fissure, the longitudinal cerebral fissure. The fissure contains the sickle-shaped fold of dura mater, the falx cerebri, and the anterior cerebral arteries. In the depths of the fissure, the great commissure, the corpus callosum, connects the hemispheres across the midline. A second horizontal fold of dura mater separates the cerebral hemispheres from the cerebellum and is called the tentorium cerebelli. To increase the surface area of the cerebral cortex maximally, the surface of each cerebral hemisphere is thrown into folds or gyri, which are separated from each other by sulci or fissures. For ease of description, it is customary to divide each hemisphere into lobes, which are named according to the cranial bones under which they lie. The central and parieto-occipital sulci and the lateral and calcarine sulci are boundaries used for the division of the cerebral hemisphere into frontal, parietal, temporal, and occipital lobes. MAIN SULCI The central sulcus is of great importance because the gyrus that lies anterior to it contains the motor cells that initiate the movements of the opposite side of the body; posterior to it lies the general sensory cortex that receives sensory information from the opposite side of the body. The central sulcus indents the superior medial border of the hemisphere about 0.4 inch (1 cm) behind the midpoint. It runs downward and forward across the lateral aspect of the hemisphere, and its lower end is separated from the posterior ramus of the lateral sulcus by a narrow bridge of cortex. The lateral sulcus is a deep cleft found mainly on the inferior and lateral surfaces of the cerebral hemisphere. It consists of a short stem that divides into three rami. The stem arises on the inferior surface, and on reaching the lateral surface, it divides into the anterior horizontal ramus and the anterior ascending ramus and continues as the posterior ramus. An area of cortex called the insula lies at the bottom of the deep lateral sulcus and cannot be seen from the surface unless the lips of the sulcus are separated. The parieto-occipital sulcus begins on the superior medial margin of the hemisphere about 2 inches (5 cm) anterior to the occipital pole. It passes downward and anteriorly on the medial surface to meet the calcarine sulcus. The calcarine sulcus is found on the medial surface of the hemisphere. It commences under the posterior end of the corpus callosum and arches upward and backward to reach the occipital pole, where it stops. In some brains, however, it continues for a short distance onto the lateral surface of the hemisphere. The calcarine sulcus is joined at an acute angle by the parieto-occipital sulcus about halfway along its length. LOBES OF THE CEREBRAL HEMISPHERE Superolateral Surface of the Hemisphere The frontal lobe occupies the area anterior to the central sulcus and superior to the lateral sulcus. The superolateral surface of the frontal lobe is divided by three sulci into four gyri. The precentral sulcus runs parallel to the central sulcus, and the precentral gyrus lies between them. Extending anteriorly from the precentral sulcus are the superior and inferior frontal sulci. The superior frontal gyrus lies superior to the superior frontal sulcus, the middle frontal gyrus lies between the superior and inferior frontal sulci, and the inferior frontal gyrus lies inferior to the inferior frontal sulcus. The inferior frontal gyrus is invaded by the anterior and ascending rami of the lateral sulcus. The parietal lobe occupies the area posterior to the central sulcus and superior to the lateral sulcus; it extends posteriorly as far as the parieto-occipital sulcus. The lateral surface of the parietal lobe is divided by two sulci into three gyri. The postcentral sulcus runs parallel to the central sulcus, and the postcentral gyrus lies between them. Running posteriorly from the middle of the postcentral sulcus is the intraparietal sulcus. Superior to the intraparietal sulcus is the superior parietal lobule (gyrus), and inferior to the intraparietal sulcus is the inferior parietal lobule (gyrus). The temporal lobe occupies the area inferior to the lateral sulcus. The lateral surface of the temporal lobe is divided into three gyri by two sulci. The superior and middle temporal sulci run parallel to the posterior ramus of the lateral sulcus and divide the temporal lobe into the superior, middle, and inferior temporal gyri; the inferior temporal gyrus is continued onto the inferior surface of the hemisphere. The occipital lobe occupies the small area behind the parieto-occipital sulcus. Medial and Inferior Surfaces of the Hemisphere The lobes of the cerebral hemisphere are not clearly defined on the medial and inferior surfaces. However, there are many important areas that should be recognized. The corpus callosum which is the largest commissure of the brain, forms a striking feature on this surface. The cingulate gyrus begins beneath the anterior end of the corpus callosum and continues above the corpus callosum until it reaches its posterior end. The gyrus is separated from the corpus callosum by the callosal sulcus. The cingulate gyrus is separated from the superior frontal gyrus by the cingulate sulcus. The paracentral lobule is the area of the cerebral cortex that surrounds the indentation produced by the central sulcus on the superior border. The anterior part of this lobule is a continuation of the precentral gyrus on the superior lateral surface, and the posterior part of the lobule is a continuation of the postcentral gyrus. The precuneus is an area of cortex bounded anteriorly by the upturned posterior end of the cingulate sulcus and posteriorly by the parieto-occipital sulcus. The cuneus is a triangular area of cortex bounded above by the parieto- occipital sulcus, inferiorly by the calcarine sulcus, and posteriorly by the superior medial margin. The collateral sulcus is situated on the inferior surface of the hemisphere. This runs anteriorly below the calcarine sulcus. Between the collateral sulcus and the calcarine sulcus is the lingual gyrus. Anterior to the lingual gyrus is the parahippocampal gyrus; the latter terminates in front as the hooklike uncus. The medial occipitotemporal gyrus extends from the occipital pole to the temporal pole. It is bounded medially by the collateral and rhinal sulci and laterally by the occipitotemporal sulcus. The occipitotemporal gyrus lies lateral to the sulcus and is continuous with the inferior temporal gyrus. On the inferior surface of the frontal lobe, the olfactory bulb and tract overlie a sulcus called the olfactory sulcus. Medial to the olfactory sulcus is the gyrus rectus, and lateral to the sulcus are a number of orbital gyri. INTERNAL STRUCTURE OF THE CEREBRAL HEMISPHERES The cerebral hemispheres are covered with a layer of gray matter, the cerebral cortex. Located in the interior of the cerebral hemispheres are the lateral ventricles, masses of gray matter, the basal nuclei, and nerve fibers. The nerve fibers are embedded in neuroglia and constitute the white matter. Basal Nuclei (Basal Ganglia) The term basal nuclei is applied to a collection of masses of gray matter situated within each cerebral hemisphere. They are the corpus striatum, the amygdaloid nucleus, and the claustrum. White Matter of the Cerebral Hemispheres The white matter is composed of myelinated nerve fibers of different diameters supported by neuroglia. The nerve fibers may be classified into three groups according to their connections: (1) commissural fibers, (2) association fibers, and (3) projection fibers. Commissure Fibers These fibers essentially connect corresponding regions of the two hemispheres. They are as follows: the corpus callo-sum, the anterior commissure, the posterior commissure, the fornix, and the habenular commissure. The corpus callosum, the largest commissure of the brain, connects the two cerebral hemispheres. It lies at the bottom of the longitudinal fissure. For purposes of description, it is divided into the rostrum, the genu, the body, and the splenium. The rostrum is the thin part of the anterior end of the corpus callosum, which is prolonged posteriorly to be continuous with the upper end of the lamina terminalis. The genu is the curved anterior end of the corpus callosum that bends inferiorly in front of the septum pellucidum. The body of the corpus callosum arches posteriorly and ends as the thickened posterior portion called the splenium. Traced laterally, the fibers of the genu curve forward into the frontal lobes and form the forceps minor. The fibers of the body extend laterally as the radiation of the corpus callosum. They intersect with bundles of association and projection fibers as they pass to the cerebral cortex. Some of the fibers form the roof and lateral wall of the posterior horn of the lateral ventricle and the lateral wall of the inferior horn of the lateral ventricle; these fibers are referred to as the tapetum. Traced laterally, the fibers in the splenium arch backward into the occipital lobe and form the forceps major. The anterior commissure is a small bundle of nerve fibers that crosses the midline in the lamina terminalis. When traced laterally, a smaller or anterior bundle curves forward on each side toward the anterior perforated substance and the olfactory tract. A larger bundle curves posteriorly on each side and grooves the inferior surface of the lentiform nucleus to reach the temporal lobes. The posterior commissure is a bundle of nerve fibers that crosses the midline immediately above the opening of the cerebral aqueduct into the third ventricle; it is related to the inferior part of the stalk of the pineal gland. Various collections of nerve cells are situated along its length. The destinations and functional significance of many of the nerve fibers are not known. However, the fibers from the pretectal nuclei involved in the pupillary light reflex are believed to cross in this commissure on their way to the parasympathetic part of the oculomotor nuclei. The fornix is composed of myelinated nerve fibers and constitutes the efferent system of the hippocampus that passes to the mammillary bodies of the hypothalamus. The nerve fibers first form the alveus, which is a thin layer of white matter covering the ventricular surface of the hippocampus, and then converge to form the fimbria. The fimbriae of the two sides increase in thickness and, on reaching the posterior end of the hippocampus, arch forward above the thalamus and below the corpus callosum to form the posterior columns of the fornix. The two columns then come together in the midline to form the body of the fornix. The commissure of the fornix consists of transverse fibers that cross the midline from one column to another just before the formation of the body of the fornix. The function of the commissure of the fornix is to connect the hippocampal formations of the two sides. The habenular commissure is a small bundle of nerve fibers that crosses the midline in the superior part of the root of the pineal stalk. The commissure is associated with the habenular nuclei, which are situated on either side of the midline in this region. The habenular nuclei receive many afferents from the amygdaloid nuclei and the hippocampus. These afferent fibers pass to the habenular nuclei in the stria medullaris thalami. Some of the fibers cross the midline to reach the contralateral nucleus through the habenular commissure. The function of the habenular nuclei and its connections in humans is unknown. Association Fibers These nerve fibers essentially connect various cortical regions within the same hemisphere and may be divided into short and long groups. The short association fibers lie immediately beneath the cortex and connect adjacent gyri; these fibers run transversely to the long axis of the sulci. The long association fibers are collected into named bundles that can be dissected in a formalin- hardened brain. The uncinate fasciculus connects the first motor speech area and the gyri on the inferior surface of the frontal lobe with the cortex of the pole of the temporal lobe. The cingulum is a long, curved fasciculus lying within the white matter of the cingulate gyrus. It connects the frontal and parietal lobes with parahippocam-pal and adjacent temporal cortical regions. The superior longitudinal fasciculus is the largest bundle of nerve fibers. It connects the anterior part of the frontal lobe to the occipital and temporal lobes. The inferior longitudinal fasciculus runs anteriorly from the occipital lobe, passing lateral to the optic radiation, and is distributed to the temporal lobe. The fronto-occipital fasciculus connects the frontal lobe to the occipital and temporal lobes. It is situated deep within the cerebral hemisphere and is related to the lateral border of the caudate nucleus. Projection Fibers Afferent and efferent nerve fibers passing to and from the brainstem to the entire cerebral cortex must travel between large nuclear masses of gray matter within the cerebral hemisphere. At the upper part of the brainstem, these fibers form a compact band known as the internal capsule, which is flanked medially by the caudate nucleus and the thalamus and laterally by the lentiform nucleus. Because of the wedge shape of the lentiform nucleus, as seen on horizontal section, the internal capsule is bent to form an anterior limb and a posterior limb, which are continuous with each other at the genu. Once the nerve fibers have emerged superiorly from between the nuclear masses, they radiate in all directions to the cerebral cortex. These radiating projection fibers are known as the corona radiata. Most of the projection fibers lie medial to the association fibers, but they intersect the commissural fibers of the corpus callosum and the anterior commissure. The nerve fibers lying within the most posterior part of the posterior limb of the internal capsule radiate toward the calcarine sulcus and are known as the optic radiation. Septum Pellucidum The septum pellucidum is a thin vertical sheet of nervous tissue consisting of white and gray matter covered on either side by ependyma. It stretches between the fornix and the corpus callosum. Anteriorly, it occupies the interval between the body of the corpus callosum and the rostrum. It is essentially a double membrane with a closed, slitlike cavity between the membranes. The septum pellucidum forms a partition between the anterior horns of the lateral ventricles. Lateral Ventricles There are two large lateral ventricles, and one is present in each cerebral hemisphere. The ventricle is a roughly C-shaped cavity and may be divided into a body, which occupies the parietal lobe and from which anterior, posterior, and inferior horns extend into the frontal, occipital, and temporal lobes, respectively. The lateral ventricle communicates with the cavity of the third ventricle through the interventricular foramen. This opening, which lies in the anterior part of the medial wall of the ventricle, is bounded anteriorly by the anterior column of the fornix and posteriorly by the anterior end of the thalamus. The body of the lateral ventricle extends from the interventricular foramen posteriorly as far as the posterior end of the thalamus. Here it becomes continuous with the posterior and the inferior horns. The body of the lateral ventricle has a roof, a floor, and a medial wall. The roof is formed by the undersurface of the corpus callosum. The floor is formed by the body of the caudate nucleus and the lateral margin of the thalamus. The superior surface of the thalamus is obscured in its medial part by the body of the fornix. The choroid plexus of the ventricle projects into the body of the ventricle through the slitlike gap between the body of the fornix and the superior surface of the thalamus. This slitlike gap is known as the choroidal fissure; through it the blood vessels of the plexus invaginate the pia mater of the tela choroidea and the ependyma of the lateral ventricle. The medial wall is formed by the septum pellucidum anteriorly; posteriorly the roof and the floor come together on the medial wall. The anterior horn of the lateral ventricle extends forward into the frontal lobe. It is continuous posteriorly with the body of the ventricle at the interventricular foramen. The anterior horn has a roof, a floor, and a medial wall. The roof is formed by the undersurface of the anterior part of the corpus callosum; the genu of the corpus callosum limits the anterior horn anteriorly. The floor is formed by the rounded head of the caudate nucleus, and medially a small portion is formed by the superior surface of the rostrum of the corpus callosum. The medial wall is formed by the septum pellucidum and the anterior column of the fornix. The posterior horn of the lateral ventricle extends posteriorly into the occipital lobe. The roof and lateral wall are formed by the fibers of the tapetum of the corpus callosum. Lateral to the tapetum are the fibers of the optic radiation. The medial wall of the posterior horn has two elevations. The superior swelling is caused by the splenial fibers of the corpus callosum, called the forceps major, passing posteriorly into the occipital lobe; this superior swelling is referred to as the bulb of the posterior horn. The inferior swelling is produced by the calcarine sulcus and is called the calcar avis. The inferior horn of the lateral ventricle extends anteriorly into the temporal lobe. The inferior horn has a roof and a floor. The roof is formed by the inferior surface of the tapetum of the corpus callosum and by the tail of the caudate nucleus. The latter passes anteriorly to end in the amygdaloid nucleus. Medial to the tail of the caudate nucleus is the stria terminalis, which also ends anteriorly in the amygdaloid nucleus. The floor is formed laterally by the collateral eminence, produced by the collateral fissure, and medially by the hippocampus. The anterior end of the hippocampus is expanded and slightly furrowed to form the pes hippocampus. The hippocampus is composed of gray matter; however, the ventricular surface of the hippocampus is covered by a thin layer of white matter called the alveus, which is formed from the axons of the cells of the hippocampus. These axons converge on the medial border of the hippocampus to form a bundle known as the fimbria. The fimbria of the hippocampus becomes continuous posteriorly with the posterior column of the fornix. In the interval between the stria terminalis and the fimbria is the temporal part of the choroidal fissure. It is here that the lower part of the choroid plexus of the lateral ventricle invaginates the ependyma from the medial side and closes the fissure.

Materials for self-check. A. Tasks for self-check: the tables show anatomical lesions surface of the forebrain. B. Choose the correct answer: 1.The physician-pathologist conducted the autopsy of 85-year-old man who died after prolonged cerebrovascular accident. In studying of the man’s brain a physician determined the presence of hemorrhage in the area of the cortex, located between the calcarine fissure and parietal-occipital sulcus (BNA). What is the name of this part of cortex? A.the cuneus B.The uncus C.The precuneus D.Limbic system E.paracentral lobule 2.A Lecturer of anatomy during the lesson was showing students the cerebral hemisphere and explained the relief structure of the cortex. One of the students asked the name of part of the cortex, located between the marginal share of the cingulate sulcus and parietal-occipital sulcus. ). What is the name of this part of cortex? A.The precuneus B.The insula C.the cuneus D.Limbic system E.The uncus 3.During the brains studying physician determined the presence a hemorrhage in the area of the cortex, located between the upper and lower frontal sulci (sulcus). What is the name of this part of cortex? A.Middle frontal gyrus B.The uncus C.The precuneus D.Superior frontal gyrus E.Inferior frontal gyrus 4.During the studying of brains physician determined the presence a hemorrhage in the area of the cortex, located below the lower frontal sulcus (sulci). What is the name of this part of cortex? A.Inferior frontal gyrus B.The uncus C.The precuneus D.Superior frontal gyrus E.Middle frontal gyrus 5.During the studying of brains physician determined the presence a hemorrhage in the area of the cortex, located fetched and occipital-temporal sulci. What is the name of this part of cortex? A.Medial occipitotemporal gyrus B.The uncus C.The precuneus D.Superior frontal gyrus E.Inferior frontal gyrus 6.A Lecturer of anatomy during the lesson was showing students the cerebral hemisphere and explained the relief structure of the cortex. One of the students asked him to name the part of the cortex, located between the marginal share of the cingulate sulcus and parietal-occipital sulcus. What is the name of this part of cortex? A.The precuneus B.The insula C.the cuneus D.Limbic system E.The uncus 7.A Lecturer of anatomy during the lesson was showing students the cerebral hemisphere and explained the relief structure of the cortex. One of the students asked him to name the part of the cortex, located between the zonality sulcus and sulcus of the corpus callosum. What is the name of this part of cortex? A.The cingulate gyrus B.The insula C.the cuneus D.The precuneus E.The uncus 8.A Lecturer of anatomy during the lesson was showing students the cerebral hemisphere and explained the relief structure of the cortex. One of the students asked him to name the part of the cortex, located between the calcarine sulcus and parietal- occipital sulcus. What is the name of this part of cortex? A.the cuneus B.The insula C.The precuneus D.Limbic system E.The uncus 9.A Lecturer of anatomy during the lesson was showing students the cerebral hemisphere and explained the relief structure of the cortex. One of the students asked him to name the part of the cortex, which covers the back end of the superior temporal gyrus. What is the name of this part of cortex? A.The angular gyrus B.The insula C.the cuneus D.The cingulate gyrus E.The uncus 10.In explaining the relief structure of the cerebral cortex of one of the students asked to name the part of the cortex, which is located between the central postcentral gyrus. What is the name of this part of cortex? A.the postcentral gyrus B.the cuneus C.The precuneus D.The cingulate gyrus E.The uncus

Topic 28. The rhinencephalon. Limbic brain. The basal nuclei. 1. Relevance of the topic: Knowledge of anatomy section end necessary for students of all specialties for further study. 2. The specific aims: To have general knowledge of the topic studied; To understand, to remember and to use the knowledge received; To form the professional experience by reviewing, training and authorizing it; To be able to find studying structure on visual aids. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). Disciplines З Know Be able 1) interim discipline Knowing the structure of Demonstrate horizontal Biology the basal nuclei of higher autopsy cerebral hemispheres mammals location basal nuclei. Histology Know the histological To be able to distinguish the structure of the basal gray, white matter, differentiated nuclei core basics 2) Courses are provided: Normal and Pathological Physiology, topographical and pathological anatomy, surgery, nerve disease. 3) Interdiscipline "The structure of the To be able to show the skull integration - skull" projection lobes. the "Osteology" main supply To be able to show the the "Angiology" brain. preparation: - Plexus chorioideus - A. carotis interna - V. jugularis interna 4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class.

Nuclei basales et structurae pertinentes Basal nuclei and the structure formations

Nucleus caudatus Caudate nucleus

Caput Head

Corpus Body

Cauda Tail

Putamen putamen

Lamina medullaris lateralis Brain lateral plate

Lamina medullaris externa External brain plate

Globus pallidus lateralis Lateral pale bullet

Lamina medullaris medialis The medial cerebral plate

Lamina medullaris interna Internal brain plate

Globus pallidus medialis The medial pale bullet

Pars lateralis The lateral part Pars medialis The medial part Corpus striatum striatum Striatum dorsale Dorsal stripe 4.2. Theoretical questions for the class: 1. Distribution of the cerebral hemispheres at the gray and white matter. 2. General characteristics of the foundations of brain nuclei. 3. Functional basal nuclei. 4. Characteristics of layers of white matter between basal nuclei. 5. Which of the basal nuclei form striatum. 6. What are the parts of the caudate nucleus is located and where each of its parts? 7. What is the fence? 4.3. Practical tasks pertaining to the topic and to be completed during the class:In isolated wet preparation to be able to show the structure and components of the olfactory brain and basal core striopalidarnu system. 1. Show the wet preparation brain thalamus, caudate nucleus, internal capsule. 2. To be able to show the fence and almond body. 3. To be able to show the red nucleus and substantia nigr of the midbrain. The content of the topic. LIMBIC SYSTEM The word limbic means border or margin, and the term limbic system was loosely used to include a group of structures that lie in the border zone between the cerebral cortex and the hypothalamus. Now it is recognized, as the result of research, that the limbic system is involved with many other structures beyond the border zone in the control of emotion, behavior, and drive; it also appears to be important to memory. Anatomically, the limbic structures include the subcallosal, the cingulate, and the parahippocampal gyri, the hippocampal formation, the amygdaloid nucleus, the mam-millary bodies, and the anterior thalamic nucleus. The alveus, the fimbria, the fornix, the mammillothalamic tract, and the stria terminalis constitute the connecting pathways of this system. Hippocampal Formation The hippocampal formation consists of the hippocampus, the dentate gyrus, and the parahippocampal gyrus. The hippocampus is a curved elevation of gray matter that extends throughout the entire length of the floor of the inferior horn of the lateral ventricle. Its anterior end is expanded to form the pes hippocampus. It is named hippocampus because it resembles a sea horse in coronal section. The convex ventricular surface is covered with ependyma, beneath which lies a thin layer of white matter called the alveus. The alveus consists of nerve fibers that have originated in the hippocampus, and these converge medially to form a bundle called the fimbria. The fimbria, in turn, becomes continuous with the crus of the fornix. The hippocampus terminates posteriorly beneath the splenium of the corpus callosum. The dentate gyrus is a narrow, notched band of gray matter that lies between the fimbria of the hippocampus and the parahippocampal gyrus. Posteriorly, the gyrus accompanies the fimbria almost to the splenium of the corpus callosum and becomes continuous with the indusium griseum. The indusium griseum is a thin, vestigial layer of gray matter that covers the superior surface of the corpus callosum. Embedded in the superior surface of the indusium griseum are two slender bundles of white fibers on each side called the medial and lateral longitudinal striae. The striae are the remains of the white matter of the vestigial indusium griseum. Anteriorly, the dentate gyrus is continued into the uncus. The parahippocampal gyrus lies between the hip-pocampal fissure and the collateral sulcus and is continuous with the hippocampus along the medial edge of the temporal lobe. Amygdaloid Nucleus The amygdaloid nucleus is so named because it resembles an almond. It is situated partly anterior and partly superior to the tip of the inferior horn of the lateral ventricle. It is fused with the tip of the tail of the caudate nucleus, which has passed anteriorly in the roof of the inferior horn of the lateral ventricle. The stria terminalis emerges from its posterior aspect. The amygdaloid nucleus consists of a complex of nuclei which can be grouped into a larger basolateral group and smaller corticomedial group. The mammillary bodies and the anterior nucleus of the thalamus are considered elsewhere in this text. Connecting Pathways of the Limbic System These pathways are the alveus, the fimbria, the fornix, the mammillothalamic tract, and the stria terminalis. The alveus consists of a thin layer of white matter that lies on the superior or ventricular surface of the hippocampus. It is composed of nerve fibers that originate in the hippocampal cortex. The fibers converge on the medial border of the hippocampus to form a bundle called the fimbria. The fimbria now leaves the posterior end of the hippocampus as the eras of the fornix. The cms from each side curves posteriorly and superiorly beneath the splenium of the corpus callosum and around the posterior surface of the thalamus. The two crura now converge to form the body of the fornix, which is applied closely to the undersurface of the corpus callosum. As the two crura come together, they are connected by transverse fibers called the commissure of the fornix. These fibers decussate and join the hippocampi of the two sides.

Anteriorly, the body of the fornix is connected to the undersurface of the corpus callosum by the septum pellucidum. Inferiorly, the body of the fornix is related to the tela choroidea and the ependymal roof of the third ventricle. The body of the fornix splits anteriorly into two anterior columns of the fornix, each of which curves anteriorly and inferiorly over the interventricular foramen (foramen of Monro). Then each column disappears into the lateral wall of the third ventricle to reach the mammillary body. The mammillothalamic tract provides important connections between the mammillary body and the anterior nuclear group of the thalamus. The stria terminalis emerges from the posterior aspect of the amygdaloid nucleus and runs as a bundle of nerve fibers posteriorly in the roof of the inferior horn of the lateral ventricle on the medial side of the tail of the caudate nucleus. It follows the curve of the caudate nucleus and comes to lie in the floor of the body of the lateral ventricle. Structure of the Hippocampus and the Dentate Gyrus The cortical structure of the parahippocampal gyrus is six-layered. As the cortex is traced into the hippocampus, there is a gradual transition from a six- to a three-layered arrangement. These three layers are the superficial molecular layer, consisting of nerve fibers and scattered small neurons; the pyramidal layer, consisting of many large pyramid-shaped neurons; and the inner polymorphic layer, which is similar in structure to the polymorphic layer of the cortex seen elsewhere. The dentate gyrus also has three layers, but the pyramidal layer is replaced by the granular layer. The granular layer is composed of densely arranged rounded or oval neurons that give rise to axons that terminate upon the dendrites of the pyramidal cells in the hippocampus. A few of the axons join the fimbria and enter the fornix. Afferent Connections of the Hippocampus Afferent connections of the hippocampus may be divided into six groups: 1. Fibers arising in the cingulate gyrus pass to the hippocampus. 2. Fibers arising from the septal nuclei (nuclei lying within the midline close to the anterior commissure) pass posterior in the fornix to the hippocampus. 3. Fibers arising from one hippocampus pass across the midline to the opposite hippocampus in the commissure of the fornix. 4. Fibers from the indusium griseum pass posteriorly in the longitudinal striae to the hippocampus. 5. Fibers from the entorhinal area or olfactory-associated cortex pass to the hippocampus. 6. Fibers arising from the dentate and parahippocampal gyri travel to the hippocampus. Efferent Connections of the Hippocampus Axons of the large pyramidal cells of the hippocampus emerge to form the alveus and the fimbria. The fimbria continues as the cms of the fornix. The two crura converge to form the body of the fornix. The body of the fornix splits into the two columns of the fornix, which curve downward and forward in front of the interventricular foramina. The fibers within the fornix are distributed to the following regions: 1. Fibers pass posterior to the anterior commissure to enter the mammillary body, where they end in the medial nucleus. 2. Fibers pass posterior to the anterior commissure to end in the anterior nuclei of the thalamus. 3. Fibers pass posterior to the anterior commissure to enter the tegmentum of the midbrain. 4. Fibers pass anterior to the anterior commissure to end in the septal nuclei, the lateral preoptic area, and the anterior part of the hypothalamus. 5. Fibers join the stria medullaris thalami to reach the habe-nular nuclei. Consideration of the above complex anatomical pathways indicates that the structures comprising the limbic system not only are interconnected, but also send projection fibers to many different parts of the nervous system. Physiologists now recognize the importance of the hypothalamus as being the major output pathway of the limbic system. Functions of the Limbic System The limbic system, via the hypothalamus and its connections with the outflow of the autonomic nervous system and its control of the endocrine system, is able to influence many aspects of emotional behavior. These include particularly the reactions of fear and anger and the emotions associated with sexual behavior. There is also evidence that the hippocampus is concerned with converting recent memory to long-term memory. A lesion of the hippocampus results in the individual being unable to store long-term memory. Memory of remote past events before the lesion developed is unaffected. This condition is called anterograde amnesia. It is interesting to note that injury to the amygdaloid nucleus and the hippocampus produces a greater memory loss than injury to either one of these structures alone. There is no evidence that the limbic system has an olfactory function. The various afferent and efferent connections of the limbic system provide pathways for the integration and effective homeostatic responses to a wide variety of environmental stimuli. BASAL NUCLEI The term basal nuclei is applied to a collection of masses of gray matter situated within each cerebral hemisphere. They are the corpus striatum, the amygdaloid nucleus, and the claustrum. Clinicians and neuroscientists use a variety of different terminologies to describe the basal nuclei. The subthalamic nuclei, the substantia nigra, and the red nucleus are functionally closely related to the basal nuclei, but they should not be included with them. The interconnections of the basal nuclei are complex, but in this account, only the more important pathways are considered. The basal nuclei play an important role in the control of posture and voluntary movement. CORPUS STRIATUM The corpus striatum is situated lateral to the thalamus and is almost completely divided by a band of nerve fibers, the internal capsule, into the caudate nucleus and the lentiform nucleus. The term striatum is used here because of the striated appearance produced by the strands of gray matter passing through the internal capsule and connecting the caudate nucleus to the putamen of the lentiform nucleus. Caudate Nucleus The caudate nucleus is a large C-shaped mass of gray matter that is closely related to the lateral ventricle and lies lateral to the thalamus. The lateral surface of the nucleus is related to the internal capsule, which separates it from the lentiform nucleus. For purposes of description, it can be divided into a head, a body, and a tail. The head of the caudate nucleus is large and rounded and forms the lateral wall of the anterior horn of the lateral ventricle. The head is continuous inferiorly with the putamen of the lentiform nucleus (the caudate nucleus and the putamen are sometimes referred to as the neostriatum or striatum). Just superior to this point of union, strands of gray matter pass through the internal capsule, giving the region a striated appearance, hence the term corpus striatum. The body of the caudate nucleus is long and narrow and is continuous with the head in the region of the interventricular foramen. The body of the caudate nucleus forms part of the floor of the body of the lateral ventricle. The tail of the caudate nucleus is long and slender and is continuous with the body in the region of the posterior end of the thalamus. It follows the contour of the lateral ventricle and continues forward in the roof of the inferior horn of the lateral ventricle. It terminates anteriorly in the amygdaloid nucleus. Lentiform Nucleus The lentiform nucleus is a wedge-shaped mass of gray matter whose broad convex base is directed laterally and whose blade is directed medially. It is buried deep in the white matter of the cerebral hemisphere and is related medially to the internal capsule, which separates it from the caudate nucleus and the thalamus. The lentiform nucleus is related laterally to a thin sheet of white matter, the external capsule, which separates it from a thin sheet of gray matter, called the claustrum. The claustrum, in turn, separates the external capsule from the subcortical white matter of the insula. A vertical plate of white matter divides the nucleus into a larger, darker lateral portion, the putamen, and an inner lighter portion, the globus pallidus. The paleness of the globus pallidus is due to the presence of a high concentration of myelinated nerve fibers. In-feriorly at its anterior end, the putamen is continuous with the head of the caudate nucleus. AMYGDALOID NUCLEUS The amygdaloid nucleus is situated in the temporal lobe close to the uncus. Through its connections, it can influence the body's response to environmental changes. In the sense of fear, for example, it can change the heart rate, blood pressure, skin color, and rate of respiration. SUBSTANTIA NIGRA AND SUBTHALAMIC NUCLEI The substantia nigra of the midbrain and the subthalamic nuclei of the diencephalon are functionally closely related to the activities of the basal nuclei. The neurons of the substantia nigra are dopaminergic and inhibitory and have many connections to the corpus striatum. The neurons of the subthalamic nuclei are glutaminergic and excitatory and have many connections to the globus pallidus and substantia nigra. CLAUSTRUM The claustrum is a thin sheet of gray matter that is separated from the lateral surface of the lentiform nucleus by the external capsule. Lateral to the claustrum is the subcortical white matter of the insula. The function of the claustrum is unknown.

FUNCTIONS OF THE BASAL NUCLEI The basal nuclei are joined together and connected with many different regions of the nervous system by a very complex number of neurons. Basically, the corpus striatum receives afferent information from most of the cerebral cortex, the thalamus, the subthalamus, and the brainstem, including the substantia nigra. The information is integrated within the corpus striatum, and the outflow passes back to the areas listed above. This circular pathway is believed to function as follows. The activity of the basal nuclei is initiated by information received from the premotor and supplemental areas of the motor cortex, the primary sensory cortex, the thalamus, and the brainstem. The outflow from the basal nuclei is channeled through the globus pallidus, which then influences the activities of the motor areas of the cerebral cortex or other motor centers in the brainstem. Thus the basal nuclei control muscular movements by influencing the cerebral cortex and have no direct control through descending pathways to the brainstem and spinal cord. In this way the basal nuclei assist in the regulation of voluntary movement and the learning of motor skills. The basal nuclei not only influence the execution of a particular movement of, say, the limbs, but also help prepare for the movements. This may be achieved by controlling the axial and girdle movements of the body and the positioning of the proximal parts of the limbs. The activity in certain neurons of the globus pallidus increases before active movements take place in the distal limb muscles. This important preparatory function enables the trunk and limbs to be placed in appropriate positions before the primary motor part of the cerebral cortex activates discrete movements in the hands and feet.

Materials for self-check. A. Tasks for self- check: the tables to designate parts of the olfactory brain and basal core striopalidarnu system. B. Choose the correct answer: 1.Patient dysfunction of the basal nuclei. To all basal nuclei include all mentioned structures except: A.Red core. B.amygdala. C.claustrum. D.caudate nucleus. E.putamen. 2.Patient violations of the striatopallidal system. The striatopallidal system is formed by: A.caudate nucleus and the lentils like core. B.caudate nucleus and claustrum. C.putamen and claustrum. D.medial and lateral pale ball. E.almond body and caudate nucleus. 3.The patient abuse striatopallidal system, in particular - in the region of the caudate nucleus. Caudate nucleus has: A.head, body, tail. B.Head, leg. C. legs, tail. D.Head, neck. E.Head, handles, legs. 4.The patient abuse striatopallidal system. system, in particular - lentils like core, which is divided: A.The putamen, lateral and medial pale sphere. B.At the putamen, caudate nucleus. C.On the putamen, claustrum D.At the almond kernel and palidum. E.On the medial and lateral pale ball. 5.When hemorrhage in areas of the forebrain the patient has got violated automatic movements. Irritation basal nuclei leads: A.To the appearance is not conscious movements. B.To the emergence of conscious movements. C.To enhance motor function of the gastrointestinal tract. D.To rejection of cold and hot. E.To reduce motor function of the gastrointestinal tract. 6.When done a CT scan of the brain of the patient revealed that damaged the left striatum. What structures belong to it from below mentioned? A.Sochevytsepodibne and caudate nucleus. B.caudate nucleus and putamen. C.Sochevytsepodibne nucleus and putamen. D.Palidum and putamen. E.medial pale ball and claustrum. 7.The patient in '30 suffered frombleeding in the brain, which damaged the putamen. The patient complains on difficulty in performing complex coordinated movements. Whose core component is the putamen? A.Lentils like core B.amygdala. C.claustrum. D.caudate nucleus. E.internal capsule 8.Damage of Striatopallidal system led to the development athetosis (rhythmic limb movements). Which cores are damaged? A.striatum. B.Front nucleus of the hypothalamus. C.medial geniculate body. D.Lateral geniculate body. E.Rear nuclei of the hypothalamus. 9.A patient was diagnosed with dancing malady. In this disease appear supplementary and forced movements. Which structures of the brain are involved in this? A.Substantia nigra et corpus striatum. B.Pulvinarthalamicus. C.Fasciculus longitudinalis medialis. D.Fasciculus longitudinalis posterior. E.Nucleus ruber. 10.When conducting a CT scan of the brain in a patient with Parkinson's disorders in the brain stem were found. In the study of forebrain detected pathologies: A.Lentils like core B.angular gyrus. C.Lateral gyrus. D.Hooks gyrus sea horse. E.almond kernel.

Topic 29. Structure of grey matter and cortex of cerebral hemispheres. Functional arrangement of the cerebral cortex. 1. Relevance of the topic: Knowledge of the topography and the structure of the brain can help in determining the correct diagnosis of the patient, since the defeat of the brain disorder arising from the loss of sensitivity of different departments, motor responses. 2. The specific aims: Analyze the structure of the forebrain, hemispheres of the brain. Explain: - Structure of the cerebral cortex; - Localization of functions in the frontal lobe of the brain; - Localization of functions in the parietal and occipital lobe of the brain; - Localization of function in the temporal lobe of the brain. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). Disciplines Know Be able 1) Interim discipline The structure of the Show the share of brain Biology mammalian brain.

Histology Tsytoarhitektonika Identify the gray and white brain. matter of the brain. 2) Courses are provided: Normal and Pathological Physiology, topographical and pathological anatomy, surgery, nerve disease. 1) Interdiscipline The structure of the skull. To be able to show well. integration - main supply Carotis 1) The "Osteology" brain. interna. 2) "Angiology" 4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class. Cortex cerebri The cerebral cortex Paleocortex Old bark Neocortex New bark 4.2. Theoretical questions for the class: 1. Share of the structure of the forebrain. 2. Share with the structure of the cerebral hemispheres. 3. Share the structure of the cerebral cortex. 4. Share the localization of functions in the frontal lobe of the brain. 5. Share the localization of functions in the parietal and occipital lobe of the brain. 6. Share the localization of functions in the temporal lobe of the brain. 4.3. Practical tasks pertaining to the topic and to be completed during the class: The content of the topic: THE CEREBRAL HEMISPHERES The cerebral hemispheres are the largest part of the brain and are separated by a deep midline sagittal fissure, the longitudinal cerebral fissure. The fissure contains the sickle-shaped fold of dura mater, the falx cerebri, and the anterior cerebral arteries. In the depths of the fissure, the great commissure, the corpus callosum, connects the hemispheres across the midline. A second horizontal fold of dura mater separates the cerebral hemispheres from the cerebellum and is called the tentorium cerebelli. To increase the surface area of the cerebral cortex maximally, the surface of each cerebral hemisphere is thrown into folds or gyri, which are separated from each other by sulci or fissures. For ease of description, it is customary to divide each hemisphere into lobes, which are named according to the cranial bones under which they lie. The central and parieto-occipital sulci and the lateral and calcarine sulci are boundaries used for the division of the cerebral hemisphere into frontal, parietal, temporal, and occipital lobes. MAIN SULCI The central sulcus is of great importance because the gyrus that lies anterior to it contains the motor cells that initiate the movements of the opposite side of the body; posterior to it lies the general sensory cortex that receives sensory information from the opposite side of the body. The central sulcus indents the superior medial border of the hemisphere about 0.4 inch (1 cm) behind the midpoint. It runs downward and forward across the lateral aspect of the hemisphere, and its lower end is separated from the posterior ramus of the lateral sulcus by a narrow bridge of cortex. The lateral sulcus is a deep cleft found mainly on the inferior and lateral surfaces of the cerebral hemisphere. It consists of a short stem that divides into three rami. The stem arises on the inferior surface, and on reaching the lateral surface, it divides into the anterior horizontal ramus and the anterior ascending ramus and continues as the posterior ramus. An area of cortex called the insula lies at the bottom of the deep lateral sulcus and cannot be seen from the surface unless the lips of the sulcus are separated. The parieto-occipital sulcus begins on the superior medial margin of the hemisphere about 2 inches (5 cm) anterior to the occipital pole. It passes downward and anteriorly on the medial surface to meet the calcarine sulcus. The calcarine sulcus is found on the medial surface of the hemisphere. It commences under the posterior end of the corpus callosum and arches upward and backward to reach the occipital pole, where it stops. In some brains, however, it continues for a short distance onto the lateral surface of the hemisphere. The calcarine sulcus is joined at an acute angle by the parieto-occipital sulcus about halfway along its length. LOBES OF THE CEREBRAL HEMISPHERE Superolateral Surface of the Hemisphere The frontal lobe occupies the area anterior to the central sulcus and superior to the lateral sulcus. The superolateral surface of the frontal lobe is divided by three sulci into four gyri. The precentral sulcus runs parallel to the central sulcus, and the precentral gyrus lies between them. Extending anteriorly from the precentral sulcus are the superior and inferior frontal sulci. The superior frontal gyrus lies superior to the superior frontal sulcus, the middle frontal gyrus lies between the superior and inferior frontal sulci, and the inferior frontal gyrus lies inferior to the inferior frontal sulcus. The inferior frontal gyrus is invaded by the anterior and ascending rami of the lateral sulcus. The parietal lobe occupies the area posterior to the central sulcus and superior to the lateral sulcus; it extends posteriorly as far as the parieto-occipital sulcus. The lateral surface of the parietal lobe is divided by two sulci into three gyri. The postcentral sulcus runs parallel to the central sulcus, and the postcentral gyrus lies between them. Running posteriorly from the middle of the postcentral sulcus is the intraparietal sulcus. Superior to the intraparietal sulcus is the superior parietal lobule (gyrus), and inferior to the intraparietal sulcus is the inferior parietal lobule (gyrus). The temporal lobe occupies the area inferior to the lateral sulcus. The lateral surface of the temporal lobe is divided into three gyri by two sulci. The superior and middle temporal sulci run parallel to the posterior ramus of the lateral sulcus and divide the temporal lobe into the superior, middle, and inferior temporal gyri; the inferior temporal gyrus is continued onto the inferior surface of the hemisphere. The occipital lobe occupies the small area behind the parieto-occipital sulcus. Medial and Inferior Surfaces of the Hemisphere The lobes of the cerebral hemisphere are not clearly defined on the medial and inferior surfaces. However, there are many important areas that should be recognized. The corpus callosum which is the largest commissure of the brain, forms a striking feature on this surface. The cingulate gyrus begins beneath the anterior end of the corpus callosum and continues above the corpus callosum until it reaches its posterior end. The gyrus is separated from the corpus callosum by the callosal sulcus. The cingulate gyrus is separated from the superior frontal gyrus by the cingulate sulcus. The paracentral lobule is the area of the cerebral cortex that surrounds the indentation produced by the central sulcus on the superior border. The anterior part of this lobule is a continuation of the precentral gyrus on the superior lateral surface, and the posterior part of the lobule is a continuation of the postcentral gyrus. The precuneus is an area of cortex bounded anteriorly by the upturned posterior end of the cingulate sulcus and posteriorly by the parieto-occipital sulcus. The cuneus is a triangular area of cortex bounded above by the parieto- occipital sulcus, inferiorly by the calcarine sulcus, and posteriorly by the superior medial margin. The collateral sulcus is situated on the inferior surface of the hemisphere. This runs anteriorly below the calcarine sulcus. Between the collateral sulcus and the calcarine sulcus is the lingual gyrus. Anterior to the lingual gyrus is the parahippocampal gyrus; the latter terminates in front as the hooklike uncus. The medial occipitotemporal gyrus extends from the occipital pole to the temporal pole. It is bounded medially by the collateral and rhinal sulci and laterally by the occipitotemporal sulcus. The occipitotemporal gyrus lies lateral to the sulcus and is continuous with the inferior temporal gyrus. On the inferior surface of the frontal lobe, the olfactory bulb and tract overlie a sulcus called the olfactory sulcus. Medial to the olfactory sulcus is the gyrus rectus, and lateral to the sulcus are a number of orbital gyri. INTERNAL STRUCTURE OF THE CEREBRAL HEMISPHERES The cerebral hemispheres are covered with a layer of gray matter, the cerebral cortex. Located in the interior of the cerebral hemispheres are the lateral ventricles, masses of gray matter, the basal nuclei, and nerve fibers. The nerve fibers are embedded in neuroglia and constitute the white matter. Basal Nuclei (Basal Ganglia) The term basal nuclei is applied to a collection of masses of gray matter situated within each cerebral hemisphere. They are the corpus striatum, the amygdaloid nucleus, and the claustrum. White Matter of the Cerebral Hemispheres The white matter is composed of myelinated nerve fibers of different diameters supported by neuroglia. The nerve fibers may be classified into three groups according to their connections: (1) commissural fibers, (2) association fibers, and (3) projection fibers. Commissure Fibers These fibers essentially connect corresponding regions of the two hemispheres. They are as follows: the corpus callo-sum, the anterior commissure, the posterior commissure, the fornix, and the habenular commissure. The corpus callosum, the largest commissure of the brain, connects the two cerebral hemispheres. It lies at the bottom of the longitudinal fissure. For purposes of description, it is divided into the rostrum, the genu, the body, and the splenium. The rostrum is the thin part of the anterior end of the corpus callosum, which is prolonged posteriorly to be continuous with the upper end of the lamina terminalis. The genu is the curved anterior end of the corpus callosum that bends inferiorly in front of the septum pellucidum. The body of the corpus callosum arches posteriorly and ends as the thickened posterior portion called the splenium. Traced laterally, the fibers of the genu curve forward into the frontal lobes and form the forceps minor. The fibers of the body extend laterally as the radiation of the corpus callosum. They intersect with bundles of association and projection fibers as they pass to the cerebral cortex. Some of the fibers form the roof and lateral wall of the posterior horn of the lateral ventricle and the lateral wall of the inferior horn of the lateral ventricle; these fibers are referred to as the tapetum. Traced laterally, the fibers in the splenium arch backward into the occipital lobe and form the forceps major. The anterior commissure is a small bundle of nerve fibers that crosses the midline in the lamina terminalis. When traced laterally, a smaller or anterior bundle curves forward on each side toward the anterior perforated substance and the olfactory tract. A larger bundle curves posteriorly on each side and grooves the inferior surface of the lentiform nucleus to reach the temporal lobes. The posterior commissure is a bundle of nerve fibers that crosses the midline immediately above the opening of the cerebral aqueduct into the third ventricle; it is related to the inferior part of the stalk of the pineal gland. Various collections of nerve cells are situated along its length. The destinations and functional significance of many of the nerve fibers are not known. However, the fibers from the pretectal nuclei involved in the pupillary light reflex are believed to cross in this commissure on their way to the parasympathetic part of the oculomotor nuclei. The fornix is composed of myelinated nerve fibers and constitutes the efferent system of the hippocampus that passes to the mammillary bodies of the hypothalamus. The nerve fibers first form the alveus, which is a thin layer of white matter covering the ventricular surface of the hippocampus, and then converge to form the fimbria. The fimbriae of the two sides increase in thickness and, on reaching the posterior end of the hippocampus, arch forward above the thalamus and below the corpus callosum to form the posterior columns of the fornix. The two columns then come together in the midline to form the body of the fornix. The commissure of the fornix consists of transverse fibers that cross the midline from one column to another just before the formation of the body of the fornix. The function of the commissure of the fornix is to connect the hippocampal formations of the two sides. The habenular commissure is a small bundle of nerve fibers that crosses the midline in the superior part of the root of the pineal stalk. The commissure is associated with the habenular nuclei, which are situated on either side of the midline in this region. The habenular nuclei receive many afferents from the amygdaloid nuclei and the hippocampus. These afferent fibers pass to the habenular nuclei in the stria medullaris thalami. Some of the fibers cross the midline to reach the contralateral nucleus through the habenular commissure. The function of the habenular nuclei and its connections in humans is unknown. Association Fibers These nerve fibers essentially connect various cortical regions within the same hemisphere and may be divided into short and long groups. The short association fibers lie immediately beneath the cortex and connect adjacent gyri; these fibers run transversely to the long axis of the sulci. The long association fibers are collected into named bundles that can be dissected in a formalin- hardened brain. The uncinate fasciculus connects the first motor speech area and the gyri on the inferior surface of the frontal lobe with the cortex of the pole of the temporal lobe. The cingulum is a long, curved fasciculus lying within the white matter of the cingulate gyrus. It connects the frontal and parietal lobes with parahippocam-pal and adjacent temporal cortical regions. The superior longitudinal fasciculus is the largest bundle of nerve fibers. It connects the anterior part of the frontal lobe to the occipital and temporal lobes. The inferior longitudinal fasciculus runs anteriorly from the occipital lobe, passing lateral to the optic radiation, and is distributed to the temporal lobe. The fronto-occipital fasciculus connects the frontal lobe to the occipital and temporal lobes. It is situated deep within the cerebral hemisphere and is related to the lateral border of the caudate nucleus. Projection Fibers Afferent and efferent nerve fibers passing to and from the brainstem to the entire cerebral cortex must travel between large nuclear masses of gray matter within the cerebral hemisphere. At the upper part of the brainstem, these fibers form a compact band known as the internal capsule, which is flanked medially by the caudate nucleus and the thalamus and laterally by the lentiform nucleus. Because of the wedge shape of the lentiform nucleus, as seen on horizontal section, the internal capsule is bent to form an anterior limb and a posterior limb, which are continuous with each other at the genu. Once the nerve fibers have emerged superiorly from between the nuclear masses, they radiate in all directions to the cerebral cortex. These radiating projection fibers are known as the corona radiata. Most of the projection fibers lie medial to the association fibers, but they intersect the commissural fibers of the corpus callosum and the anterior commissure. The nerve fibers lying within the most posterior part of the posterior limb of the internal capsule radiate toward the calcarine sulcus and are known as the optic radiation. Septum Pellucidum The septum pellucidum is a thin vertical sheet of nervous tissue consisting of white and gray matter covered on either side by ependyma. It stretches between the fornix and the corpus callosum. Anteriorly, it occupies the interval between the body of the corpus callosum and the rostrum. It is essentially a double membrane with a closed, slitlike cavity between the membranes. The septum pellucidum forms a partition between the anterior horns of the lateral ventricles.

Materials for self-control: A. Tasks for self-control: explain about brain function. B. Choose the correct answer: 1.After a head injury in the neck there was a loss of vision. What appeared in the survey? A.Revealed pathological process in the cortical end of the visual analyzer (part calcarine grooves). B.The pathological process is localized in the parietal lobe of the brain. C.The pathological process is localized in the medial geniculate body. D.The pathological process is localized in the cerebellum. E.The pathological process is localized in the medulla oblongata. 2.The patient (right-handed) lost the ability to fine movements needed to images of letters, words and other symbols (ahrafiya). What is the area of the cerebral cortex is affected? A.Posterior middle frontal gyrus in the left hemisphere. B.The average share peredtsentralnoyi gyrus in the left hemisphere. C.Posterior middle frontal gyrus in the right hemisphere. D.The average share peredtsentralnoyi gyrus in the right hemisphere. E.The rear section of the upper frontal gyrus in the right hemisphere. 3.After a head injury patient hears the language, understands it, but can not correctly identify the subject. In which area of the cerebral cortex damage occurred? A.The lower frontal gyrus. B.The upper frontal gyrus. C.In front of the central gyrus. D.In the middle frontal gyrus. E.In the middle temporal gyrus. 4.The patient, who had previously worked as a mechanic, suddenly lost the ability to use tools in the process. In which area of the cerebral cortex appeared cell destruction? A.In supramarginal gyrus. B.In the angular gyrus. C.In the superior temporal gyrus. D.In the upper parietal lobules. E.In the occipital lobe. 5.The patient suddenly lost the ability to read text, see the letter, but unable to make one word. In which area of cerebral cortex lesion has occurred? A.In the angular gyrus. B.In the middle temporal gyrus. C.In supramarginal gyrus. D.In the upper parietal lobules. E.In the occipital lobe. 6.When examining a patient with traumatic injuries of the cerebral cortex revealed that he has lost tactile sensitivity. What cortex was damaged? A.Bark posterior central gyrus. B.Frontal lobe cortex. C.Occipital lobe cortex. D.Parietal lobe cortex. E.Bark anterior central gyrus. 7.Patients after cerebral blood flow lost the ability to write letters and numbers. What proportion of brain pathology there. A.In the frontal lobe. B.In the insular. C.In the parietal lobe. D.In the occipital lobe. E.In the temporal lobe. 8.The patient came unilateral paralysis of the left lower limb. In which area of the cerebral cortex localized pathological focus? A.In the right precentral gyrus B.In a back central gyrus. C.In an average temporal gyrus. D.In the top parietal lobe. E.In the left precentral gyrus. 9.The patient hemorrhage postcentral gyrus. To breach kind of sensitivity with the other side it will lead? A.Skin. B.Olfactory and gustatory. C.Auditory and visual. D.Auditory E.Visual 10.After a brain injury patient has lost the ability to pronounce words clearly. In some areas of the cerebral cortex lesion appeared? A.In the frontal lobe. B.In the occipital lobe. C.In the parietal lobe. D.In the temporal lobe. E.In the insular.

Theme 30. The lateral ventricles. The white matter of thecerebral hemispheres. Meninges of the brain. Circulation of cerebrospinal liquid. 1. Relevance of the topic: Knowledge of the topography, the structure of the brain will help in determining the correct diagnosis of the patient, since the defeat of the brain there are serious disturbances of different kinds of loss of sensitivity, motor responses. Will help be prevented inflammation and traumatic brain damage. 2. The specific aims: Analyze residue which is a think bubble lateral ventricles. To explain: - part of the lateral ventricles; - Structures that form the walls of each of the lateral ventricles; - Part of the corpus callosum; - Anterior commissure of the brain where it is located, connecting; - Vaults of the brain; - Structure of the hard shell of the brain; - Shoots hard shell of the brain; - The creation and circulation of cerebrospinal fluid paths. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). Disciplines Know Be able 1) interim Know the structural features Distinguish between membranes discipline of the membranes of the of the brain and spinal cord Biology brain of higher mammals subshell spaces Histology Know the histological To be able to distinguish structure of hard, soft and histological preparations arachnoid membranes of membrane of the brain. мозку 2) Courses are provided with normal and abnormal physiology, topographical and pathological anatomy, surgery, nerve disease. 3) Interdiscipline Location furrows To be able to show the skull integration - sinus dura sulcus sinus dura the "Osteology" brain. brain. the "Angiology" main supply To be able to show the brain outflow of venous preparation: blood. - Plexus chorioideus - A. carotis interna - V. jugularis interna 4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class. Commissure Commissure Cavum Cavity Lamina Plate Nucleus precommissuralis Before the adhesive core Ventriculus lateralis Lateral ventricles Taenia choroidea vascular plexus Fissura choroidea Vascular gap Corpus callosum Corpus callosum Fornix Vault 4.2. Theoretical questions for the class: 1. Remains of which are cerebral lateral ventricles bubble? 2.Which parts consists of each of the lateral ventricles and where each of them placed? 3. What structures form the walls of each of the lateral ventricles? 4. With what and with which combined lateral ventricles? 5. What distinguished spikes brain? 6. What are the parts of the body or corpus is a large spike the brain? 7. What is the anterior commissure of the brain where it is located, connecting? 8. Where transparent partition is located and what it is? 9. What are the parts of the arch is the brain? 10. Name the show and associative fibers. 11. Name and show commissural fibers. 12. Name and show the internal capsule, its limits, parts. 13. Name and pathways show the front leg of the internal capsule. 14. Name and show pathways knee internal capsule. 15. Name and show pathways rear legs inside the capsule. 16. How is the brain membranes, as they are called and how placing order? 4.3. Practical tasks pertaining to the topic and to be completed during the class: 1. demonstrates membrane on preparations brain: solid, soft. Indicates the features of their structure. 2. preparations and processes dummies demonstrated the dura of the brain: cerebral sickle, cerebellar sickle, cerebellar tent diaphragm saddle. The content of the topic. MENINGES OF THE BRAIN The brain and spinal cord are surrounded by three membranes, or meninges: the dura mater, the arachnoid mater, and the pia mater. Dura Mater The dura mater of the brain is conventionally described as two layers, the endosteal layer and the meningeal layer. These are closely united except along certain lines, where they separate to form venous sinuses. The endosteal layer is nothing more than the periosteum covering the inner surface of the skull bones. At the foramen magnum, it does not become continuous with the dura mater of the spinal cord. Around the margins of all the foramina in the skull, it becomes continuous with the periosteum on the outside of the skull bones. At the sutures, it is continuous with the sutural ligaments. It is most strongly adherent to the bones over the base of the skull. The meningeal layer is the dura mater proper. It is a dense, strong fibrous membrane covering the brain and is continuous through the foramen magnum with the dura mater of the spinal cord. It provides tubular sheaths for the cranial nerves as the latter pass through the foramina in the skull. Outside the skull, the sheaths fuse with the epineurium of the nerves. The meningeal layer sends inward four septa, which divide the cranial cavity into freely communicating spaces that lodge the subdivisions of the brain. The function of these septa is to restrict the displacement of the brain associated with acceleration and deceleration, when the head is moved. The falx cerebri is a sickle-shaped fold of dura mater that lies in the midline between the two cerebral hemispheres. Its narrow anterior end is attached to the internal frontal crest and the crista galli. Its broad posterior part blends in the midline with the upper surface of the tentorium cerebelli. The superior sagittal sinus runs in its upper fixed margin; the inferior sagittal sinus runs in its lower concave free margin; and the straight sinus runs along its attachment to the tentorium cerebelli. The tentorium cerebelli is a crescent-shaped fold of dura mater that roofs over the posterior cranial fossa. It covers the upper surface of the cerebellum and supports the occipital lobes of the cerebral hemispheres. In the anterior edge there is a gap, the tentorial notch, for the passage of the midbrain, which produces an inner free border and an outer attached or fixed border. The fixed border is attached to the posterior clinoid processes, the superior borders of the petrous bones, and the margins of the grooves for the transverse sinuses on the occipital bone. The free border runs forward at its two ends, crosses the attached border, and is affixed to the anterior clinoid process on each side. At the point where the two borders cross, the third and fourth cranial nerves pass forward to enter the lateral wall of the cavernous sinus. Close to the apex of the petrous part of the temporal bone, the lower layer of the tentorium is pouched forward beneath the superior petrosal sinus to form a recess for the trigeminal nerve and the trigeminal ganglion. The falx cerebri and the falx cerebelli are attached to the upper and lower surfaces of the tentorium, respectively. The straight sinus runs along its attachment to the falx cerebri; the superior petrosal sinus runs along its attachment to the petrous bone; and the transverse sinus runs along its attachment to the occipital bone. The falx cerebelli, a small, sickle-shaped fold of dura mater attached to the internal occipital crest, projects forward between the two cerebellar hemispheres. Its posterior fixed margin contains the occipital sinus. The diaphragma sellae is a small, circular fold of dura mater that forms the roof for the sella turcica. A small opening in its center allows passage of the stalk of the hypophysis cerebri. Dural Venous Sinuses The venous sinuses of the cranial cavity are situated between the layers of the dura mater. Their main function is to receive blood from the brain through the cerebral veins and the cerebrospinal fluid from the subarachnoid space through the arachnoid villi. The blood in the dural sinuses ultimately drains into the internal jugular veins in the neck. The dural sinuses are lined by endothelium, and their walls are thick but devoid of muscular tissue. They have no valves. Emissary veins, which are also valveless, connect the dural venous sinuses with the diploic veins of the skull and with the veins of the scalp. The superior sagittal sinus occupies the upper fixed border of the falx cerebri. It begins anteriorly at the foramen cecum,.where it occasionally receives a vein from the nasal cavity. It runs posteriorly, grooving the vault of the skull, and at the internal occipital protuberance it deviates to one or the other side (usually the right) and becomes continuous with the corresponding transverse sinus. The sinus communicates through small openings with two or three irregularly shaped venous lacunae on each side. Numerous arachnoid villi and granulations project into the lacunae, which also receive the diploic and meningeal veins. The superior sagittal sinus in its course receives the superior cerebral veins. At the internal occipital protuberance, it is dilated to form the confluence of the sinuses. Here, the superior sagittal sinus usually becomes continuous with the right transverse sinus; it is connected to the opposite transverse sinus and receives the occipital sinus. The inferior sagittal sinus occupies the free lower margin of the falx cerebri. It runs backward and joins the great cerebral vein at the free margin of the tentorium cerebelli, to form the straight sinus. It receives a few cerebral veins from the medial surface of the cerebral hemispheres. The straight sinus occupies the line of junction of the falx cerebri with the tentorium cerebelli. It is formed by the union of the inferior sagittal sinus with the great cerebral vein. It ends by turning to the left (sometimes to the right) to form the transverse sinus. The transverse sinuses are paired structures and begin at the internal occipital protuberance. The right sinus is usually continuous with the superior sagittal sinus, and the left is continuous with the straight sinus. Each sinus occupies the attached margin of the tentorium cerebelli, grooving the occipital bone and the pos-teroinferior angle of the parietal bone. The transverse sinuses receive the superior petrosal sinuses, the inferior cerebral and cerebellar veins, and the diploic veins. They end by turning downward as the sigmoid sinuses. The sigmoid sinuses are a direct continuation of the transverse sinuses. Each sinus turns downward and medially and grooves the mastoid part of the temporal bone. It is here that the sinus lies posterior to the mastoid antrum. The sinus then turns forward and then inferiorly through the posterior part of the jugular foramen to become continuous with the superior bulb of the internal jugular vein. The occipital sinus is a small sinus occupying the attached margin of the falx cerebelli. It commences near the foramen magnum, where it communicates with the vertebral veins and drains into the confluence of sinuses. The cavernous sinuses are situated in the middle cranial fossa on each side of the body of the sphenoid bone. Numerous trabeculae cross their interior, giving them a spongy appearance, hence the name. Each sinus extends from the superior orbital fissure in front to the apex of the petrous part of the temporal bone behind. The tributaries are the superior and inferior ophthalmic veins, the inferior cerebral veins, the sphenoparietal sinus, and the central vein of the retina. The sinus drains posteriorly into the superior and inferior petrosal sinuses and inferiorly into the pterygoid venous plexus. The two sinuses communicate with each other by means of the anterior and posterior intercavernous sinuses, which run in the diaphragma sellae anterior and posterior to the stalk of the hypophysis cerebri. Each sinus has an important communication with the facial vein through the superior ophthalmic vein. (This is a route by which infection can travel from the facial skin to the cavernous sinus.) The superior and inferior petrosal sinuses are small sinuses situated on the superior and inferior borders of the petrous part of the temporal bone on each side of the skull. Each superior sinus drains the cavernous sinus into the transverse sinus, and each inferior sinus drains the cavernous sinus into the internal jugular vein. ARACHNOID MATER The arachnoid mater is a delicate, impermeable membrane covering the brain and lying between the pia mater internally and the dura mater externally. It is separated from the dura by a potential space, the subdural space, filled by a film of fluid; it is separated from the pia by the subarachnoid space, which is filled with cerebrospinal fluid. The outer and inner surfaces of the arachnoid are covered with flattened mesothelial cells. The arachnoid bridges over the sulci on the surface of the brain, and in certain situations the arachnoid and pia are widely separated to form the subarachnoid cisternae. The cisterna cerebellomedullaris lies between the inferior surface of the cerebellum and the roof of the fourth ventricle. The cisterna interpeduncularis lies between the two cerebral peduncles. All the cisternae are in free communication with one another and with the remainder of the subarachnoid space. In certain areas, the arachnoid projects into the venous sinuses to form arachnoid villi. The arachnoid villi are most numerous along the superior sagittal sinus. Aggregations of arachnoid villi are referred to as arachnoid granulations. Arachnoid villi serve as sites where the cerebrospinal fluid diffuses into the bloodstream. The arachnoid is connected to the pia mater across the fluid-filled subarachnoid space by delicate strands of fibrous tissue. Structures passing to and from the brain to the skull or its foramina must pass through the subarachnoid space. All the cerebral arteries and veins lie in the space, as do the cranial nerves. The arachnoid fuses with the epineurium of the nerves at their point of exit from the skull. The cerebrospinal fluid is produced by the choroid plexuses within the lateral, third, and fourth ventricles of the brain. It escapes from the ventricular system of the brain through the three foramina in the roof of the fourth ventricle and so enters the subarachnoid space. It now circulates both upward over the surfaces of the cerebral hemispheres and downward around the spinal cord. The spinal subarachnoid space extends down as far as the second sacral vertebra (see next column). Eventually, the fluid enters the bloodstream by passing into the arachnoid villi and diffusing through their walls. In addition to removing waste products associated with neuronal activity, the cerebrospinal fluid provides a fluid medium in which the brain floats. This mechanism effectively protects the brain from trauma. In addition, the fluid is now believed to play a role in hormonal transport. PIA MATER The pia mater is a vascular membrane covered by flattened mesothelial cells. It closely invests the brain, covering the gyri and descending into the deepest sulci. It extends out over the cranial nerves and fuses with their epineurium. The cerebral arteries entering the substance of the brain carry a sheath of pia with them. The pia mater forms the tela choroidea of the roof of the third and fourth ventricles of the brain, and it fuses with the ependyma to form the choroid plexuses in the lateral, third, and fourth ventricles of the brain. MENINGES OF THE SPINAL CORD Dura Mater. The dura mater is a dense, strong, fibrous membrane that en- closes the spinal cord and the cauda equina. It is continuous above through the foramen magnum with the meningeal layer of dura covering the brain. Inferiorly, it ends on the filum terminale at the level of the lower border of the second sacral vertebra. The dural sheath lies loosely in the vertebral canal and is separated from the wall of the canal by the extradural space. This contains loose areolar tissue and the internal vertebral venous plexus. The dura mater extends along each nerve root and becomes continuous with the connective tissue surrounding each spinal nerve (epineurium). The inner surface of the dura mater is in contact with the arachnoid mater. Arachnoid Mater. The arachnoid mater is a delicate impermeable membrane that covers the spinal cord and lies between the pia mater internally and dura mater externally. It is separated from the pia mater by a wide space, the subarachnoid space, which is filled with cerebrospinal fluid. The subarachnoid space is crossed by a number of fine strands of connective tissue. The arachnoid mater is continuous above through the foramen magnum with the arachnoid covering the brain. Inferiorly, it ends on the filum terminale at the level of the lower border of the second sacral vertebra. The arachnoid mater continues along the spinal nerve roots, forming small lateral extensions of the subarachnoid space. Pia Mater. The pia mater, a vascular membrane that closely covers the spinal cord, is thickened on either side between the nerve roots to form the ligamentum denticulatum, which passes laterally to adhere to the arachnoid and dura. It is by this means that the spinal cord is suspended in the middle of the dural sheath. The pia mater extends along each nerve root and becomes continuous with the connective tissue surrounding each spinal nerve. VENTRICULAR SYSTEM The ventricles are four fluid-filled cavities located within the brain; these are the two lateral ventricles, the third ventricle, and the fourth ventricle. The two lateral ventricles communicate through the interventricular foramina (of Monro) with the third ventricle. The third ventricle is connected to the fourth ventricle by the narrow cerebral aqueduct (aqueduct of Sylvius). The fourth ventricle, in turn, is continuous with the narrow central canal of the spinal cord and, through the three foramina in its roof, with the subarachnoid space. The central canal in the spinal cord has a small dilatation at its inferior end, referred to as the terminal ventricle. The ventricles are lined throughout with ependyma and are filled with cerebrospinal fluid. The ventricles are developmentally derived from the cavity of the neural tube. SUBARACHNOID SPACE The subarachnoid space is the interval between the arachnid mater and pia mater and, therefore, is present where these meninges envelop the brain and spinal cord. The space is filled with cerebrospinal fluid and contains the large blood vessels of the brain. This space is traversed by a network of fine trabeculae, formed of delicate connective tissue. The subarachnoid space completely surrounds the brain and extends along the olfactory nerves to the mucoperiosteum of the nose. The subarachnoid space also extends along the cerebral blood vessels as they enter and leave the substance of the brain and stops where the vessels become an arteriole or a venule. In certain situations around the base of the brain, the arachnoid does not closely follow the surface of the brain so that the subarachnoid space expands to form subarachnoid cisterns. The descriptions of the cerebellomedullary cistern, the pontine cistern, and the interpeduncular cistern, which are the largest cisterns. Inferiorly, the subarachnoid space extends beyond the lower end of the spinal cord and invests the cauda equina. The subarachnoid space ends below at the level of the interval between the second and third sacral vertebrae. The subarachnoid space surrounds the cranial and spinal nerves and follows them to the point where they leave the skull and vertebral canal. Here the arachnoid mater and pia mater fuse with the perineurium of each nerve. CEREBROSPINAL FLUID The cerebrospinal fluid is found in the ventricles of the brain and in the subarachnoid space around the brain and spinal cord. It is a clear, colorless fluid. It possesses, in solution, inorganic salts similar to those in the blood plasma. The glucose content is about half that of blood, and there is only a trace of protein. Only a few cells are present, and these are lymphocytes. The normal lymphocyte count is 0 to 3 cells per cubic millimeter. The pressure of the cerebrospinal fluid is kept remarkably constant. In the lateral recumbent position, the pressure, as measured by spinal tap, is about 60 to 150 mm of water. This pressure may be raised by straining, coughing, or compressing the internal jugular veins in the neck. The total volume of cerebrospinal fluid in the subarachnoid space and within the ventricles is about 130 ml. Functions. The cerebrospinal fluid, which bathes the external and internal surfaces of the brain and spinal cord, serves as a cushion between the central nervous system and the surrounding bones, thus protecting it against mechanical trauma. Because the density of the brain is only slightly greater than that of the cerebrospinal fluid, it provides mechanical buoyancy and support for the brain. The close relationship of the fluid to the nervous tissue and the blood enables it to serve as a reservoir and assist in the regulation of the contents of the skull. For example, if the brain volume or the blood volume increases, the cerebrospinal fluid volume decreases. Since the cerebrospinal fluid is an ideal physiological substrate, it probably plays an active part in the nourishment of the nervous tissue; it almost certainly assists in the removal of products of neuronal metabolism. It is possible that the secretions of the pineal gland influence the activities of the pituitary gland by circulating through the cerebrospinal fluid in the third ventricle. Formation. The cerebrospinal fluid is formed mainly in the choroid plexuses of the lateral, third, and fourth ventricles; some originates from the ependymal cells lining the ventricles and from the brain substance through the perivascular spaces. The choroid plexuses have a much folded surface, and each fold consists of a core of vascular connective tissue covered with cuboidal epithelium of the ependyma. Electron-microscopic examination of the epithelial cells shows that their free surfaces are covered with microvilli. The blood of the capillaries is separated from the ventricular lumen by endothelium, a basement membrane, and the surface epithelium. The epithelial cells are fenestrated and permeable to large molecules. The choroid plexuses actively secrete cerebrospinal fluid, and this creates a small pressure gradient. At the same time, they actively transport nervous system metabolites from the cerebrospinal fluid into the blood. Active transport also explains the fact that the concentrations of potassium, calcium, magnesium, bicarbonate, and glucose are lower in the cerebrospinal fluid than in the blood plasma. The cerebrospinal fluid is produced continuously at a rate of about 0.5 ml per minute and with a total volume of about 130 ml; this corresponds to a turnover time of about 5 hours. It is important to realize that the production of cerebrospinal fluid is not pressure regulated (as in the case of blood pressure) and it continues to be produced even if the reabsorption mechanisms are obstructed. Circulation. The circulation begins with its secretion from the choroid plexuses in the ventricles and its production from the brain surface. The fluid passes from the lateral ventricles into the third ventricle through the interventricular foramina. It then passes into the fourth ventricle through the narrow cerebral aqueduct. The circulation is aided by the arterial pulsations of the choroid plexuses and by the cilia on the ependymal cells lining the ventricles. From the fourth ventricle, the fluid passes slowly through the median aperture and the lateral foramina of the lateral recesses of the fourth ventricle and enters the subarachnoid space. The fluid then moves through the cerebellomedullary cistern and pontine cisterns and flows superiorly through the tentorial notch of the tentorium cerebelli to reach the inferior surface of the cerebrum. It then moves superiorly over the lateral aspect of each cerebral hemisphere, assisted by the pulsations of the cerebral arteries. Some of the cerebrospinal fluid moves inferiorly in the subarachnoid space around the spinal cord and cauda equina. Here the fluid is at a dead end, and its further circulation relies on the pulsations of the spinal arteries and the movements of the vertebral column, respiration, coughing, and the changing of the positions of the body. The cerebrospinal fluid not only bathes the ependymal and pial surfaces of the brain and spinal cord but also penetrates the nervous tissue along the blood vessels. Absorption. The main sites for the absorption of the cerebrospinal fluid are the arachnoid villi that project into the dural venous sinuses, especially the superior sagittal sinus. The arachnoid villi tend to be grouped together to form elevations known as arachnoid granulations. Structurally, each arachnoid villus is a diverticulum of the subarachnoid space that pierces the dura mater. The arachnoid diverticulum is capped by a thin cellular layer, which, in turn, is covered by the endothelium of the venous sinus. The arachnoid granulations increase in number and size with age and tend to become calcified with advanced age. The absorption of cerebrospinal fluid into the venous sinuses occurs when the cerebrospinal fluid pressure exceeds the venous pressure in the sinus. Electron- microscopic studies of the arachnoid villi indicate that fine tubules lined with endothelium permit a direct flow of fluid from the subarachnoid space into the lumen of the venous sinuses. Should the venous pressure rise and exceed the cerebrospinal fluid pressure, compression of the tips of the villi closes the tubules and prevents the reflux of blood into the subarachnoid space. The arachnoid villi thus serve as valves. Lateral Ventricles There are two large lateral ventricles, and one is present in each cerebral hemisphere. The ventricle is a roughly C-shaped cavity and may be divided into a body, which occupies the parietal lobe and from which anterior, posterior, and inferior horns extend into the frontal, occipital, and temporal lobes, respectively. The lateral ventricle communicates with the cavity of the third ventricle through the interventricular foramen. This opening, which lies in the anterior part of the medial wall of the ventricle, is bounded anteriorly by the anterior column of the fornix and posteriorly by the anterior end of the thalamus. The body of the lateral ventricle extends from the interventricular foramen posteriorly as far as the posterior end of the thalamus. Here it becomes continuous with the posterior and the inferior horns. The body of the lateral ventricle has a roof, a floor, and a medial wall. The roof is formed by the undersurface of the corpus callosum. The floor is formed by the body of the caudate nucleus and the lateral margin of the thalamus. The superior surface of the thalamus is obscured in its medial part by the body of the fornix. The choroid plexus of the ventricle projects into the body of the ventricle through the slitlike gap between the body of the fornix and the superior surface of the thalamus. This slitlike gap is known as the choroidal fissure; through it the blood vessels of the plexus invaginate the pia mater of the tela choroidea and the ependyma of the lateral ventricle. The medial wall is formed by the septum pellucidum anteriorly; posteriorly the roof and the floor come together on the medial wall. The anterior horn of the lateral ventricle extends forward into the frontal lobe. It is continuous posteriorly with the body of the ventricle at the interventricular foramen. The anterior horn has a roof, a floor, and a medial wall. The roof is formed by the undersurface of the anterior part of the corpus callosum; the genu of the corpus callosum limits the anterior horn anteriorly. The floor is formed by the rounded head of the caudate nucleus, and medially a small portion is formed by the superior surface of the rostrum of the corpus callosum. The medial wall is formed by the septum pellucidum and the anterior column of the fornix. The posterior horn of the lateral ventricle extends posteriorly into the occipital lobe. The roof and lateral wall are formed by the fibers of the tapetum

of the corpus callosum. Lateral to the tapetum are the fibers of the optic radiation. The medial wall of the posterior horn has two elevations. The superior swelling is caused by the splenial fibers of the corpus callosum, called the forceps major, passing posteriorly into the occipital lobe; this superior swelling is referred to as the bulb of the posterior horn. The inferior swelling is produced by the calcarine sulcus and is called the calcar avis. The inferior horn of the lateral ventricle extends anteriorly into the temporal lobe. The inferior horn has a roof and a floor. The roof is formed by the inferior surface of the tapetum of the corpus callosum and by the tail of the caudate nucleus. The latter passes anteriorly to end in the amygdaloid nucleus. Medial to the tail of the caudate nucleus is the stria terminalis, which also ends anteriorly in the amygdaloid nucleus. The floor is formed laterally by the collateral eminence, produced by the collateral fissure, and medially by the hippocampus. The anterior end of the hippocampus is expanded and slightly furrowed to form the pes hippocampus. The hippocampus is composed of gray matter; however, the ventricular surface of the hippocampus is covered by a thin layer of white matter called the alveus, which is formed from the axons of the cells of the hippocampus. These axons converge on the medial border of the hippocampus to form a bundle known as the fimbria. The fimbria of the hippocampus becomes continuous posteriorly with the posterior column of the fornix. In the interval between the stria terminalis and the fimbria is the temporal part of the choroidal fissure. It is here that the lower part of the choroid plexus of the lateral ventricle invaginates the ependyma from the medial side and closes the fissure.

Materials for self-check: A. Tasks for self-check: to mark tables lateral ventricles and membranes of the brain and ways cerebral circulation and CSF. B. Choose the correct answer: 1.Because of stroke (bleeding in the brain), the patient has no volitional movements of muscles of the head and neck. Examination of the brain using MRI showed hematoma is the knee of the internal capsule. Which pathways is damaged? A.Тг. соrtісо-nuclearis B.Тг. соrtісо-frоntо-pontius. C.Тг. соrtiсо-spinalis. D.Тг. согtiсо-thalamicus. E.Тг. thalamo-соrtiсаlis. 2.Prophylactic examination showed a reduction in all kinds of sensitivity on the right half of the body. Additional survey NMR showed a small brain tumor localized in the rear leg of the internal left capsule. Damage of which pathway was the cause of the mentioned symptoms? A.Tr. spino-thalamicus. B.The central visual way. C.Tr. cortico-spinalis. D.Tr. cortuico-nuclearis. E.Central auditory way. 3.Patient hydrocephalus - dropsy on the brain. On MRI enlargement of the lateral ventricles. The third ventricle is not expanded. At the level of the holes which held occlusion circulation of cerebrospinal fluid? A.interventricular holes. B.Odd middle roof vents IV ventricle (Mazhendi`s). C.Right side roof vents IV ventricle (Lyushko`s). D.The left side of the roof vents IV ventricle (Lyushko`s). E.aqueducts brain. 4.The patient has white matter lesions, which extends from the pillars to the arch of the corpus callosum and consists of two plates. Point the lesions: A.transparent partition B.head of the caudate nucleus C.corpus callosum D.thalamus E.body arch. 5.During the examination of the brain using MRI were revealed markedly dilated lateral and third ventricles. The doctor diagnosed blockade of cerebrospinal fluid pathways. Determine the level of occlusion. A.Cerebral aqueduc B.between ventricular holes. C.median aperture of the fourth ventricle. D.The side openings of the fourth ventricle. E.Pacchioni's granulations 6.After inflammation of the brain (encephalitis) was found elevated cerebrospinal fluid pressure in the right lateral ventricle of the brain. What could be related to this phenomenon? A.Closure of the interventricular hole on the right. B.Closure of the interventricular hole left. C.imperforate of central canal of the spinal cord. D.imperforate of plumbing brain. E.imperforate of holes of Mazhendi and Lyushko of IV ventricle. 7.In the neurosurgical department enrolled patient with damage of the upper wall of the lateral ventricle center. It is formed by: A.Corpus callosum B.septum pelucidum C.Caput caudati D.Thalamus E.fornix 8.In the neurosurgical department enrolled patient with damage of the lower wall of the anterior horn of the lateral ventricle. It is formed by: A.Caput n. caudati B.septum pelucidum C.Corpus callosum D.Thalamus E.fornix 9.Patient has been diagnosed the injury of substantia alba that connects the papillary bodies with seahorse and is situated under the mesolobus. Point lesions: A.fornix B.septum pelucidum C.Caput caudati D.Corpus callosum E.Thalamus 10.Patient has been diagnosed the injury of substantia alba that is situated from the temporal and parietal lobes of the cortex to the inferior frontal gyrus. Point lesions: A.radius reflectitur B.Caput caudati C.Corpus callosum D.thalamus E.fornix

Literature. Basic: 1.Human Anatomy. In three volumes. Volume 2 / Edited by V.G. Koveshnikov. - Lugansk: LTD «Virtualnaya realnost», 2008. – 248p. 2.Human Anatomy. In three volumes. Volume 3 / Edited by V.G. Koveshnikov. - Lugansk: LTD «Virtualnaya realnost», 2009. – 384p. 3.Gray′s anatomy for students / Richard L. Drake, A. Wayne Vogl, and Adam W. M. Mitchell; illustrations by Richard M. Tibbitts and Paul E. Richardson; photographs by Ansell Horn. – 2nd ed. 2012 – 1103p. 4.Sobotta Atlas of Human Anatomy / Edited by R. Putz and R. Pabst, 14th ed. – Elsevier GmbH, Munich, 2008 . – 895p. 5.Clay JH, Pounds DM. Basic Clinical Massage Therapy: Integrating Anatomy and Treatment. 2003. 6.Grant′s atlas of anatomy ∕ Anne M.R., Arthur F. Dalley II, 12th ed. - Baltimore: Wiliams & Wolters, 2009. – 864 p. 7.Martini Frederic H. Martini′s atlas of the human body, 8th ed. – Pearson Education, 2009. – 250p. 8.Atlas of Human Anatomy / Frank H. Netter, M.D. Arthur F. Dalley; 2nd ed. // ILS, Medimedia USA Company, 1997. – 548p. The additional literature: 1.Langman J. Medical embryology / Langman J. – Baltimore, London, 1981. – 384p. 2.Crouse G.S. Development of the female urogenital system / G.S. Crouse // Semin. Reprod. Endocrinol. – 1986. – V.4, №1. – P. 1-11. 3.Beck F. Human embryology: 2 ed / F. Beck, D. Mossat, D. Davies. - Oxford: Blackwell, 1985. – V. 11. – 372p. 4.Moore Keith L. Clinically oriented anatomy: third ed / Keith L. Moore. – 1992. - 917p. 5.Clinical Anatomy. Applied anatomy for clinical students and junior doctors: eleventh edition / Harold Ellis // Oxford, UK: Blackwell publishing. – 2006. – 455p. 6.Pocket atlas of Human Anatomy / Heinz Feneis, Wolfgang Dauber // Thieme, Stuttgart. – 2000. – 510p. 7. https://human.biodigital.com/ 8. http://anatom.ua/nomina-anatomica/

Topic 31-32. General esthesiology. Visual analyzer. Eyeball: layers, chambers, refracting medias. Accessory structures of visual analyzer. Nervous pathway of visual analyzer. 1. Relevance of the topic: Information about sense organs, the eye and related structures, the accessory visual structures, the pathway of the visual analyzer are important for students of all specialties for further study. 2. The specific aims: Explain to students the structure of the eye, explore the utility of the device body, leading the way visual analyzer. 3. Basic knowledge and skills necessary to study the topic (inter-disciplinary integration). The The acquired knowledge preceding subjects Biology phylogeny visual analyzer;

Topics for further study. 4. The tasks for students' individual work. 4.1. The list of basic terms, parameters, characteristics which the student should master while preparing for the class. Organa sensorium Sense organs Bulbus oculi Eyeball Tunica fibrosa bulbi Fibrous membrane of the eye Tunica vasculosa bulbi Choroid Cornea Cornea Musculus ciliaris Ciliary muscle Iris Iris Lens The lens Camerae bulbi Cameras eyeball Apparatus lacrimalis Lacrimal apparatus

4.2. Theoretical questions for the class: 1. Components of the visual analyzer? 2. The represented capsule eyeball? 3. Structure and function of membranes eyeball? 4. Components of the uvea and their functions? 5. avilable inner lining of the eyeball? 6. What structures form the inner core of the eyeball? 7. Structure cameras eyeball creation and circulation of fluid inside the eye? 8. What applies to support staff eye? 9. Where are the cortical and subcortical centers of authority? 10.Providnyy way of eye. 11. Define the term "blyzorukist" "dalnozorkist" that these methods may correct blurred vision? 4.3. Practical tasks pertaining to the topic and to be completed during the class: working with wet preparations, models, decision of test tasks and situational problems with the database "Step 1" The content of the topic. The Organ of Sight; the visual organ (Organum Visus; The Eye). Related terminology: oculus (Lat.) and ophthalmos (Greek) stand for «eye». The bulb of the eye (bulbus oculi; eyeball), or organ of sight, is contained in the cavity of the orbit, where it is protected from injury and moved by the ocular muscles. Associated with it are certain accessory structures, viz., the muscles, fasciæ, eyebrows, eyelids, conjunctiva, and lacrimal apparatus. The bulb of the eye is imbedded in the fat of the orbit, but is separated from it by a thin membranous sac, the fascia bulbi. It is composed of segments of two spheres of different sizes. The anterior segment is one of a small sphere; it is transparent, and forms about one-sixth of the bulb. It is more prominent than the posterior segment, which is one of a larger sphere, and is opaque, and forms about five-sixths of the bulb. The term anterior pole is applied to the central point of the anterior curvature of the bulb, and that of posterior pole to the central point of its posterior curvature; a line joining the two poles forms the optic axis. The axes of the two bulbs are nearly parallel, and therefore do not correspond to the axes of the orbits, which are directed forward and lateralward. The optic nerves follow the direction of the axes of the orbits, and are therefore not parallel; each enters its eyeball 3 mm. to the nasal side and a little below the level of the posterior pole. The bulb measures rather more in its transverse and antero-posterior diameters than in its vertical diameter, the former amounting to about 24 mm., the latter to about 23.5 mm.; in the female all three diameters are rather less than in the male; its antero-posterior diameter at birth is about 17.5 mm., and at puberty from 20 to 21 mm. From without inward the three tunics are: (1) A fibrous tunic, consisting of the sclera behind and the cornea in front; (2) a vascular pigmented tunic, comprising, from behind forward, the choroid, ciliary body, and iris; and (3) a nervous tunic, the retina. The Fibrous Tunic (tunica fibrosa oculi).—The sclera and cornea form the fibrous tunic of the bulb of the eye; the sclera is opaque, and constitutes the posterior five- sixths of the tunic; the cornea is transparent, and forms the anterior sixth. The sclera has received its name from its extreme density and hardness; it is a firm, unyielding membrane, serving to maintain the form of the bulb. It is much thicker behind than in front; the thickness of its posterior part is 1 mm. Its external surface is of white color, and is in contact with the inner surface of the fascia of the bulb; it is quite smooth, except at the points where the Recti and Obliqui are inserted into it; its anterior part is covered by the conjunctival membrane. The cornea is the projecting transparent part of the external tunic, and forms the anterior sixth of the surface of the bulb. It is almost circular in outline, occasionally a little broader in the transverse than in the vertical direction. It is convex anteriorly and projects like a dome in front of the sclera. Its degree of curvature varies in different individuals, and in the same individual at different periods of life, being more pronounced in youth than in advanced life. The Vascular Tunic (tunica vasculosa oculi) — The vascular tunic of the eye is formed from behind forward by the choroid, the ciliary body, and the iris. The choroid invests the posterior five-sixths of the bulb, and extends as far forward as the ora serrata of the retina. The ciliary body connects the choroid to the circumference of the iris. The iris is a circular diaphragm behind the cornea, and presents near its center a rounded aperture, the pupil. The choroid is a thin, highly vascular membrane, of a dark brown or chocolate color, investing the posterior five-sixths of the globe; it is pierced behind by the optic nerve, and in this situation is firmly adherent to the sclera. It is thicker behind than in front. Its outer surface is loosely connected by the lamina suprachorioidea with the sclera; its inner surface is attached to the pigmented layer of the retina. The ciliary body comprises the orbiculus ciliaris, the ciliary processes, and the Ciliaris muscle. The iris has received its name from its various colors in different individuals. It is a thin, circular, contractile disk, suspended in the aqueous humor between the cornea and lens, and perforated a little to the nasal side of its center by a circular aperture, the pupil. By its periphery it is continuous with the ciliary body, and is also connected with the posterior elastic lamina of the cornea by means of the pectinate ligament; its surfaces are flattened, and look forward and backward, the anterior toward the cornea, the posterior toward the ciliary processes and lens. The iris divides the space between the lens and the cornea into an anterior and a posterior chamber. The anterior chamber of the eye is bounded in front by the posterior surface of the cornea; behind by the front of the iris and the central part of the lens. The posterior chamber is a narrow chink behind the peripheral part of the iris, and in front of the suspensory ligament of the lens and the ciliary processes. In the adult the two chambers communicate through the pupil, but in the fetus up to the seventh month they are separated by the membrana pupillaris. The Retina (tunica interna).—The retina is a delicate nervous membrane, upon which the images of external objects are received. Its outer surface is in contact with the choroid; its inner with the hyaloid membrane of the vitreous body. Behind, it is continuous with the optic nerve; it gradually diminishes in thickness from behind forward, and extends nearly as far as the ciliary body, where it appears to end in a jagged margin, the ora serrata. Here the nervous tissues of the retina end, but a thin prolongation of the membrane extends forward over the back of the ciliary processes and iris, forming the pars ciliaris retinæ and pars iridica retinæ already referred to. This forward prolongation consists of the pigmentary layer of the retina together with a stratum of columnar epithelium. The retina is soft, semitransparent, and of a purple tint in the fresh state, owing to the presence of a coloring material named rhodopsin or visual purple; but it soon becomes clouded, opaque, and bleached when exposed to sunlight. Exactly in the center of the posterior part of the retina, corresponding to the axis of the eye, and at a point in which the sense of vision is most perfect, is an oval yellowish area, the macula lutea; in the macula is a central depression, the fovea centralis. At the fovea centralis the retina is exceedingly thin, and the dark color of the choroid is distinctly seen through it. About 3 mm. to the nasal side of the macula lutæ is the entrance of the optic nerve (optic disk), the circumference of which is slightly raised to form an eminence (colliculus nervi optici); the arteria centralis retinæ pierces the center of the disk. This is the only part of the surface of the retina which is insensitive to light, and it is termed the blind spot. Macula Lutea and Fovea Centralis.—In the macula lutea the nerve fibers are wanting as a continuous layer, the ganglionic layer consists of several strata of cells, there are no rods, but only cones, which are longer and narrower than in other parts, and in the outer nuclear layer there are only cone-granules, the processes of which are very long and arranged in curved lines. In the fovea centralis the only parts present are (1) the cones; (2) the outer nuclear layer, the cone-fibers of which are almost horizontal in direction; (3) an exceedingly thin inner plexiform layer. The pigmented layer is thicker and its pigment more pronounced than elsewhere. The color of the macula seems to imbue all the layers except that of the rods and cones; it is of a rich yellow, deepest toward the center of the macula, and does not appear to be due to pigment cells, but simply to a staining of the constituent parts. At the ora serrata the nervous layers of the retina end abruptly, and the retina is continued onward as a single layer of columnar cells covered by the pigmented layer. This double layer is known as the pars ciliaris retinæ, and can be traced forward from the ciliary processes on to the back of the iris, where it is termed the pars iridica retinæ or uvea. The Refracting Media. The refracting media are three, viz.: Aqueous humor. Vitreous body. Crystalline lens. The Aqueous Humor (humor aqueus). — The aqueous humor fills the anterior and posterior chambers of the eyeball. It is small in quantity, has an alkaline reaction, and consists mainly of water, less than one-fiftieth of its weight being solid matter, chiefly chloride of sodium. The Vitreous Body (corpus vitreum). — The vitreous body forms about four-fifths of the bulb of the eye. It fills the concavity of the retina, and is hollowed in front, forming a deep concavity, the hyaloid fossa, for the reception of the lens. It is transparent, of the consistence of thin jelly, and is composed of an albuminous fluid enclosed in a delicate transparent membrane, the hyaloid membrane. It has been supposed, by Hannover, that from its surface numerous thin lamellæ are prolonged inward in a radiating manner, forming spaces in which the fluid is contained. In the adult, these lamellæ cannot be detected even after careful microscopic examination in the fresh state, but in preparations hardened in weak chromic acid it is possible to make out a distinct lamellation at the periphery of the body. In the center of the vitreous body, running from the entrance of the optic nerve to the posterior surface of the lens, is a canal, the hyaloid canal, filled with lymph and lined by a prolongation of the hyaloid membrane. This canal, in the embryonic vitreous body, conveyed the arteria hyaloidea from the central artery of the retina to the back of the lens. The fluid from the vitreous body is nearly pure water; it contains, however, some salts, and a little albumin. The Crystalline Lens (lens crystallina).—The crystalline lens, enclosed in its capsule, is situated immediately behind the iris, in front of the vitreous body, and encircled by the ciliary processes, which slightly overlap its margin. The Accessory Organs of the Eye (Organa Oculi Accessoria) The accessory organs of the eye include the ocular muscles, the conjunctiva, and the lacrimal apparatus. The Ocular Muscles (musculi oculi).—The ocular muscles are the: Rectus inferior. Rectus medialis. Rectus superior. Rectus lateralis. Obliquus inferior. Obliquus superior. The four Recti arise from a fibrous ring (annulus tendineus communis) which surrounds the upper, medial, and lower margins of the optic foramen and encircles the optic nerve. The ring is completed by a tendinous bridge prolonged over the lower and medial part of the superior orbital fissure and attached to a tubercle on the margin of the great wing of the sphenoid, bounding the fissure. Two specialized parts of this fibrous ring may be made out: a lower, the ligament, which gives origin to the Rectus inferior, part of the Rectus internus, and the lower head of origin of the Rectus lateralis; and an upper, which gives origin to the Rectus superior, the rest of the Rectus medialis, and the upper head of the Rectus lateralis. This upper band is sometimes termed the superior tendon of Lockwood. Each muscle passes forward in the position implied by its name, to be inserted by a tendinous expansion into the sclera, about 6 mm. from the margin of the cornea. Between the two heads of the Rectus lateralis is a narrow interval, through which pass the two divisions of the oculomotor nerve, the nasociliary nerve, the abducent nerve, and the ophthalmic vein. Although these muscles present a common origin and are inserted in a similar manner into the sclera, there are certain differences to be observed in them as regards their length and breadth. The Rectus medialis is the broadest, the Rectus lateralis the longest, and the Rectus superior the thinnest and narrowest. The Obliquus oculi superior (superior oblique) is a fusiform muscle, placed at the upper and medial side of the orbit. It arises immediately above the margin of the optic foramen, above and medial to the origin of the Rectus superior, and, passing forward, ends in a rounded tendon, which plays in a fibrocartilaginous ring or pulley attached to the trochlear fovea of the frontal bone. The contiguous surfaces of the tendon and ring are lined by a delicate mucous sheath, and enclosed in a thin fibrous investment. The tendon is reflected backward, lateralward, and downward beneath the Rectus superior to the lateral part of the bulb of the eye, and is inserted into the sclera, behind the equator of the eyeball, the insertion of the muscle lying between the Rectus superior and Rectus lateralis. The Obliquus oculi inferior (inferior oblique) is a thin, narrow muscle, placed near the anterior margin of the floor of the orbit. It arises from the orbital surface of the maxilla, lateral to the lacrimal groove. Passing lateralward, backward, and upward, at first between the Rectus inferior and the floor of the orbit, and then between the bulb of the eye and the Rectus lateralis, it is inserted into the lateral part of the sclera between the Rectus superior and Rectus lateralis, near to, but somewhat behind the insertion of the Obliquus superior. The Lacrimal Apparatus (apparatus lacrimalis) consists of (a) the lacrimal gland, which secretes the tears, and its excretory ducts, which convey the fluid to the surface of the eye; (b) the lacrimal ducts, the lacrimal sac, and the nasolacrimal duct, by which the fluid is conveyed into the cavity of the nose. The Lacrimal Gland (glandula lacrimalis). — The lacrimal gland is lodged in the lacrimal fossa, on the medial side of the zygomatic process of the frontal bone. It is of an oval form, about the size and shape of an almond, and consists of two portions, described as the superior and inferior lacrimal glands. The superior lacrimal gland is connected to the periosteum of the orbit by a few fibrous bands, and rests upon the tendons of the Recti superioris and lateralis, which separate it from the bulb of the eye. The inferior lacrimal gland is separated from the superior by a fibrous septum, and projects into the back part of the upper eyelid, where its deep surface is related to the conjunctiva. The ducts of the glands, from six to twelve in number, run obliquely beneath the conjunctiva for a short distance, and open along the upper and lateral half of the superior conjunctival fornix. Structures of the Lacrimal Gland — In structure and general appearance the lacrimal resembles the serous salivary glands. In the recent state the cells are so crowded with granules that their limits can hardly be defined. They contain oval nuclei, and the cell protoplasm is finely fibrillated. The Lacrimal Ducts (ductus lacrimalis; lacrimal canals).—The lacrimal ducts, one in each eyelid, commence at minute orifices, termed puncta lacrimalia, on the summits of the papillæ lacrimales, seen on the margins of the lids at the lateral extremity of the lacus lacrimalis. The superior duct, the smaller and shorter of the two, at first ascends, and then bends at an acute angle, and passes medialward and downward to the lacrimal sac. The inferior duct at first descends, and then runs almost horizontally to the lacrimal sac. At the angles they are dilated into ampullæ; their walls are dense in structure and their mucous lining is covered by stratified squamous epithelium, placed on a basement membrane. Outside the latter is a layer of striped muscle, continuous with the lacrimal part of the Orbicularis oculi; at the base of each lacrimal papilla the muscular fibers are circularly arranged and form a kind of sphincter. The Lacrimal Sac (saccus lacrimalis).—The lacrimal sac is the upper dilated end of the nasolacrimal duct, and is lodged in a deep groove formed by the lacrimal bone and frontal process of the maxilla. It is oval in form and measures from 12 to 15 mm. in length; its upper end is closed and rounded; its lower is continued into the nasolacrimal duct. Its superficial surface is covered by a fibrous expansion derived from the medial palpebral ligament, and its deep surface is crossed by the lacrimal part of the Orbicularis oculi, which is attached to the crest on the lacrimal bone. The Nasolacrimal Duct (ductus nasolacrimalis; nasal duct).—The nasolacrimal duct is a membranous canal, about 18 mm. in length, which extends from the lower part of the lacrimal sac to the inferior meatus of the nose, where it ends by a somewhat expanded orifice, provided with an imperfect valve, the plica lacrimalis (Hasneri), formed by a fold of the mucous membrane. It is contained in an osseous canal, formed by the maxilla, the lacrimal bone, and the inferior nasal concha; it is narrower in the middle than at either end, and is directed downward, backward, and a little lateralward. The mucous lining of the lacrimal sac and nasolacrimal duct is covered with columnar epithelium, which in places is ciliated. Materials for self-check. A. Tasks for self-check: show and name on tables structure the eyeball(layers, chambers, refracting medias). 1. Name three compartments of analyzer. 2. Name types of receptors featured by sense organs. 3. Name parts of the visual analyzer. 4. Describe development, developmental anomalies and external features of eyeball. 5. Name and recognize the layers of eyeball. 6. Describe the retractive media of eyeball. 7. The structure of chambers of eyeball, the production and circulation of the aqueous humor. 8. Describe the accessory visual structures. 9. Describe the visual pathway. B. Choose the correct answer: 1. To the ophthalmologist the woman with complaints to sight deterioration has addressed. At inspection the diagnosis has been established: a coloboma (a slitlike foramen at one of the eyeball structures). What of structures is involved? A.Iris B.Corpus vitreum C.Lens D.Cornea E.Corpus ciliare 2. To the oculist the patient of pension age has addressed. After the carried investigation the glaucoma (ophthalmotonus rising) is diagnosed. The cause of it is deterioration of outflow of fluid from an eye anterior chamber. What structure does not carry out function inherent in it? A. Subchoroidal space B. Slit spaces iridokorneal angle C. Vitreous body. D. Pupil E. Perichoroidal space 3. The patient of 45 years old, has addressed to the doctor with complaints to possibility loss to distinguish colours that has appeared after the tolerated electrical trauma. After survey of a retina of an eye lesions of receptors which are responsible for this kind of sensitivity are found. What it for receptors? A. Bipolar cells B. The rod C. The cones D. Amacrine cells E Horizontal cells 4. The patient of 52 years old, complains of a pain of eyeballs. At survey ophthalmotonus rising is found. Disturbance of outflow of what fluid has provoked the given state? A. Lymph B. Endolimph C. Perilymph D. Aqueous humor E. Tears 5. The patient had a steady expansion of the pupil after application of drops which contain atropine. Name muscle which does not work? A. The dilator pupillae B. The superior rectus C. The ciliary muscle D. The medial rectus E. The sphincter pupillae 6. In the patient with rupture of a. carotis interna in the cavernous sinus is observed pulsating exophthalmos (sync pulse), blowing noise is listened (in the eyeball), expansion orbit fissure. Which pair of cranial nerves that pass in sinus cavernosus with damaged vessel, hematoma compressed? A III, IV, VI, I branch of the V. B II, IV, I branch of the V. C IV, VI, a branch of the V. D VI. E VII. 7. A patient with epidemic encephalitis has uni- or bilateral ptosis (blepharoptosis), divergent strabismus (squint), accomodation disorder, dilation pupil (mydriatic pupils). The nuclei of what pair of cranial nerves have been affected? A IV B III C I branch of the V. D VI. E VII. 8. In patients with epidemic encephalitis observed one-or two-sided ptosis (drooping eyelids), strabismus divergent, disturbance of accommodation. The pupils were dilated. Nuclei which pair of cranial nerves affected? A V B IV. C III. D VI. E VII. 9. The patient turned to the eye doctor with complaints of ptosis. The examination was diagnosed with brain tumors. The core of a pair of cranial nerves affected pathological process? A VII B II C IV D III E VI 10. A patient has appealed with complaints of visual impairment accompanied by blepharoptosis, impossibility to lift the eyeball upwards and to the middle. Examination has shown that the eyeball is diverted outside, the pupil is dilated, does not react to light, the patient can′t see at a short distance. Which nerve has been injured? A n. abducens dexter B n. trochlearis C n. opticus D n. abducens sinister E n. oculomotorius

Topic 33 -34. General characteristic of organ for hearing. External and middle ears. Bones of middle ear, tympanic cavity, its walls. Internal ear. Periotic and otic labyrinths. The eights pair of cranial nervous. 1. Relevance of the topic. Information about sense organs, the ear and the pathways of the auditory analyzer, the neural pathways of the vestibular analyzer are important for students of all specialties for further study. 2. The specific aims. Explain to students general characteristics of the organ of hearing and balance, learn the components of the hearing, the structure of the external, middle and inner ear, auditory pathways analyzer. 3. Basic knowledge and skills necessary to study the topic (inter- disciplinary integration): The The acquired knowledge preceding subjects Physical Of sound waves; Biology Phylogeny hearing and balance; Topics for further study. 4. The tasks for stydents’ individual work. 4.1. The list of basic terms, parameters characteristic which the student master while preparing for the class:

Auris externa External ear Auricula Auricle Helix Helix Antihelix Antihelix Meatus acusticus externus The external ear canal Auris media middle ear Malleus Malleus Incus Incus Stapes stirrup 4.2. Theoretical questions for the class: 1. Name and recognize the principal parts of ear. 2. Discuss embryonic development of the ear and its developmental anomalies. 3. Describe the external ear. 4. Describe the auricle. 5. Describe the external acoustic meatus. 6. Describe the tympanic membrane. 7. Describe the middle ear. 8. Describe the tympanic cavity with related canals. 9. Describe the auditoryossicles with related joints and muscles. 10. Describe the auditory tube. 4.3. Practical questions for the class: working anatomical preparations, models, decision of test tasks and situational problems. The content of the topics. The Organ of Hearing (Organon Auditus; The Ear). The ear, or organ of hearing, is divisible into three parts: the external ear, the middle ear or tympanic cavity, and the internal ear or labyrinth. The external ear consists of the expanded portion named the auricula or pinna, and the external acoustic meatus. The former projects from the side of the head and serves to collect the vibrations of the air by which sound is produced; the latter leads inward from the bottom of the auricula and conducts the vibrations to the tympanic cavity. The External Acoustic Meatus (meatus acusticus externus; external auditory canal or meatus) extends from the bottom of the concha to the tympanic membrane. It is about 4 cm. in length if measured from the tragus; from the bottom of the concha its length is about 2.5 cm. It forms an S-shaped curve, and is directed at first inward, forward, and slightly upward (pars externa); it then passes inward and backward (pars media), and lastly is carried inward, forward, and slightly downward (pars interna). It is an oval cylindrical canal, the greatest diameter being directed downward and backward at the external orifice, but nearly horizontally at the inner end. It presents two constrictions, one near the inner end of the cartilaginous portion, and another, the isthmus, in the osseous portion, about 2 cm. from the bottom of the concha. The tympanic membrane, which closes the inner end of the meatus, is obliquely directed; in consequence of this the floor and anterior wall of the meatus are longer than the roof and posterior wall. The external acoustic meatus is formed partly by cartilage and membrane, and partly by bone, and is lined by skin. The cartilaginous portion (meatus acusticus externus cartilagineus) is about 8 mm. in length; it is continuous with the cartilage of the auricula, and firmly attached to the circumference of the auditory process of the temporal bone. The cartilage is deficient at the upper and back part of the meatus, its place being supplied by fibrous membrane; two or three deep fissures are present in the anterior part of the cartilage. The osseous portion (meatus acusticus externus osseus) is about 16 mm. in length, and is narrower than the cartilaginous portion. It is directed inward and a little forward, forming in its course a slight curve the convexity of which is upward and backward. Its inner end is smaller than the outer, and sloped, the anterior wall projecting beyond the posterior for about 4 mm.; it is marked, except at its upper part, by a narrow groove, the tympanic sulcus, in which the circumference of the tympanic membrane is attached. Its outer end is dilated and rough in the greater part of its circumference, for the attachment of the cartilage of the auricula. The front and lower parts of the osseous portion are formed by a curved plate of bone, the tympanic part of the temporal, which, in the fetus, exists as a separate ring (annulus tympanicus,) incomplete at its upper part. Relations of the Meatus.—In front of the osseous part is the condyle of the mandible, which however, is frequently separated from the cartilaginous part by a portion of the parotid gland. The movements of the jaw influence to some extent the lumen of this latter portion. Behind the osseous part are the mastoid air cells, separated from the meatus by a thin layer of bone. The middle ear or tympanic cavity is an irregular, laterally compressed space within the temporal bone. It is filled with air, which is conveyed to it from the nasal part of the pharynx through the auditory tube. It contains a chain of movable bones, which connect its lateral to its medial wall, and serve to convey the vibrations communicated to the tympanic membrane across the cavity to the internal ear. The tympanic cavity consists of two parts: the tympanic cavity proper, opposite the tympanic membrane, and the attic or epitympanic recess, above the level of the membrane; the latter contains the upper half of the malleus and the greater part of the incus. Including the attic, the vertical and antero-posterior diameters of the cavity are each about 15 mm. The transverse diameter measures about 6 mm. above and 4 mm. below; opposite the center of the tympanic membrane it is only about 2 mm. The tympanic cavity is bounded laterally by the tympanic membrane; medially, by the lateral wall of the internal ear; it communicates, behind, with the tympanic antrum and through it with the mastoid air cells, and in front with the auditory tube. The Tympanic Membrane (membrana tympani) separates the tympanic cavity from the bottom of the external acoustic meatus. It is a thin, semitransparent membrane, nearly oval in form, somewhat broader above than below, and directed very obliquely downward and inward so as to form an angle of about fifty-five degrees with the floor of the meatus. The auditory tube (tuba auditiva; Eustachian tube) is the channel through which the tympanic cavity communicates with the nasal part of the pharynx. Its length is about 36 mm., and its direction is downward, forward, and medialward, forming an angle of about 45 degrees with the sagittal plane and one of from 30 to 40 degrees with the horizontal plane. It is formed partly of bone, partly of cartilage and fibrous tissue. The tympanic cavity contains a chain of three movable ossicles, the malleus, incus, and stapes. The first is attached to the tympanic membrane, the last to the circumference of the fenestra vestibuli, the incus being placed between and connected to both by delicate articulations. The internal ear is the essential part of the organ of hearing, receiving the ultimate distribution of the auditory nerve. It is called the labyrinth, from the complexity of its shape, and consists of two parts: the osseous labyrinth, a series of cavities within the petrous part of the temporal bone, and the membranous labyrinth, a series of communicating membranous sacs and ducts, contained within the bony cavities. The Osseous Labyrinth (labyrinthus osseus) — The osseous labyrinth consists of three parts: the vestibule, semicircular canals, and cochlea. These are cavities hollowed out of the substance of the bone, and lined by periosteum; they contain a clear fluid, the perilymph, in which the membranous labyrinth is situated. The Vestibule (vestibulum).—The vestibule is the central part of the osseous labyrinth, and is situated medial to the tympanic cavity, behind the cochlea, and in front of the semicircular canals. It is somewhat ovoid in shape, but flattened transversely; it measures about 5 mm. from before backward, the same from above downward, and about 3 mm. across. In its lateral or tympanic wall is the fenestra vestibuli, closed, in the fresh state, by the base of the stapes and annular ligament. On its medial wall, at the forepart, is a small circular depression, the recessus sphæricus, which is perforated, at its anterior and inferior part, by several minute holes (macula cribrosa media) for the passage of filaments of the acoustic nerve to the saccule; and behind this depression is an oblique ridge, the crista vestibuli, the anterior end of which is named the pyramid of the vestibule. This ridge bifurcates below to enclose a small depression, the fossa cochlearis, which is perforated by a number of holes for the passage of filaments of the acoustic nerve which supply the vestibular end of the ductus cochlearis. As the hinder part of the medial wall is the orifice of the aquæductus vestibuli, which extends to the posterior surface of the petrous portion of the temporal bone. It transmits a small vein, and contains a tubular prolongation of the membranous labyrinth, the ductus endolymphaticus, which ends in a cul-de-sac between the layers of the dura mater within the cranial cavity. On the upper wall or roof is a transversely oval depression, the recessus ellipticus, separated from the recessus sphæricus by the crista vestibuli already mentioned. The pyramid and adjoining part of the recessus ellipticus are perforated by a number of holes (macula cribrosa superior). The apertures in the pyramid transmit the nerves to the utricle; those in the recessus ellipticus the nerves to the ampullæ of the superior and lateral semicircular ducts. Behind are the five orifices of the semicircular canals. In front is an elliptical opening, which communicates with the scala vestibuli of the cochlea. The Bony Semicircular Canals (canales semicirculares ossei).—The bony semicircular canals are three in number, superior, posterior, and lateral, and are situated above and behind the vestibule. They are unequal in length, compressed from side to side, and each describes the greater part of a circle. Each measures about 0.8 mm. in diameter, and presents a dilatation at one end, called the ampulla, which measures more than twice the diameter of the tube. They open into the vestibule by five orifices, one of the apertures being common to two of the canals. The Cochlea. — The cochlea bears some resemblance to a common snail-shell; it forms the anterior part of the labyrinth, is conical in form, and placed almost horizontally in front of the vestibule; its apex (cupula) is directed forward and lateralward, with a slight inclination downward, toward the upper and front part of the labyrinthic wall of the tympanic cavity; its base corresponds with the bottom of the internal acoustic meatus, and is perforated by numerous apertures for the passage of the cochlear division of the acoustic nerve. It measures about 5 mm. from base to apex, and its breadth across the base is about 9 mm. It consists of a conical shaped central axis, the modiolus; of a canal, the inner wall of which is formed by the central axis, wound spirally around it for two turns and three- quarters, from the base to the apex; and of a delicate lamina, the osseous spiral lamina, which projects from the modiolus, and, following the windings of the canal, partially subdivides it into two. In the recent state a membrane, the basilar membrane, stretches from the free border of this lamina to the outer wall of the bony cochlea and completely separates the canal into two passages, which, however, communicate with each other at the apex of the modiolus by a small opening named the helicotrema. The modiolus is the conical central axis or pillar of the cochlea. Its base is broad, and appears at the bottom of the internal acoustic meatus, where it corresponds with the area cochleæ; it is perforated by numerous orifices, which transmit filaments of the cochlear division of the acoustic nerve; the nerves for the first turn and a half pass through the foramina of the tractus spiralis foraminosus; those for the apical turn, through the foramen centrale. The canals of the tractus spiralis foraminosus pass up through the modiolus and successively bend outward to reach the attached margin of the lamina spiralis ossea. Here they become enlarged, and by their apposition form the spiral canal of the modiolus, which follows the course of the attached margin of the osseous spiral lamina and lodges the spiral ganglion (ganglion of Corti). The foramen centrale is continued into a canal which runs up the middle of the modiolus to its apex. The modiolus diminishes rapidly in size in the second and succeeding coil. The Membranous Labyrinth (labyrinthus membranaceus) — The membranous labyrinth is lodged within the bony cavities just described, and has the same general form as these; it is, however, considerably smaller, and is partly separated from the bony walls by a quantity of fluid, the perilymph. In certain places it is fixed to the walls of the cavity. The membranous labyrinth contains fluid, the endolymph, and on its walls the ramifications of the acoustic nerve are distributed. Within the osseous vestibule the membranous labyrinth does not quite preserve the form of the bony cavity, but consists of two membranous sacs, the utricle, and the saccule. Materials for self. A. Tasks for self-check. Show on tables, structure of organ for hearing. B. Choose the correct answer. 1. In the рatient was diagnosed mesootitis (inflammation of the mucousa of the middle ear). This morbid condition was complicated with mastoiditis (inflammation of the mucousa of the mastoid process). On which wall of the tympanic cavity are holes that connect the tympanic cavity and cells of the mastoid process? A. Posterior wall B. Medial wall C. Lateral wall D. Upper wall E. Anterior wall 2. In the the child was found signs of meningitis (inflammation of the dura mater) which appeared after suffering of the boy from a purulent otitis (inflammation of the inner ear). Through which way infection could spread in the dura mater? A. Utriculosaccular duct B. Endolymphatic duct C. Aqueductus cochleae D. Oval window E. Round window 3. In the patient is observed the smoke from the ear while he is smoking out. What is the structure of the organ of hearing was damaged? A. The cochlea B. The vestibule C. The tympanic membrane D. The auditory ossicles E. The Eustachian tube 4. Boy 4 years old often suffer from pneumonias. As a result - he has enlarging tonsils, which close pharyngeal opening of auditory tube. The auditory tube connects the cavity of the pharynx with: A. With the larynx B. With an inner ear C. With the nasal cavity D. With the middle ear E. With the oral cavity 5. At the patient the deсrease of the acuteness of the hearing is observed. What anatomical structure does not participate in carrying out of mechanical vibrations of the organ of Corti (spiral organ)? A. The cochlea B. The vestibule C. The tympanic membrane D. The auditory ossicles E. The Eustachian tube 6. To the doctor the woman, 54 years old, with complaints to giddiness, a nausea, disturbance of balance after falling and a head injury has addressed. Disturbance of function of what structure of the internal ear is more probable? A. Bony labyrinth B. The auditory tube C. The tympanic cavity D. Tympanic membrane E. The malleus 7. The child, 7 years, often is ill acute respiratory diseases. At survey substantial growth of a pharyngeal tonsil that occludes a pharyngeal foramen of the tuba auditiva is taped. It has led to the decrease of acoustical sensitivity at the child. On what wall of the tympanic cavity does the auditory tube open? A. Paries jugularis B. Paries caroticus C. Paries labyrinthicus. D. Paries mastoideus. E. Paries tegmentalis. 8. The patient, 18 years old, has addressed to hospital with complaints of noise painful sensations in the ear. At objective inspection at the patient acute respiratory disease, a rhinitis has been found. Through what foramen in the pharynx the infection contamination has got to the tempanic cavity and has entailed its inflammation? A. Choanae B. Tympanic opening of auditory tube C. Pharyngeal opening of auditory tube D. The mouth E. Entrance to the larynx 9. The diagnosis the mastoiditis is put to the patient. Specify a probable source of the diffusion of the pyoinflammatory process in mastoid alveoles. A. The tensor tympani muscle B. The auditory tube C. Tympanic membrane D. The tympanic cavity E. The stapedius muscle 10. At the child, 2 years old, after the tolerated flu have appeared complaints to a pain in an ear. The doctor has found the deсrease of hearing and the inflammation of the mucous of the middle ear. How the infection contamination has got to a middle ear? A. Due to the auditory tube B. A foramen jugularis. C. A canalis caroticus. D. After atrium mastoideum. E. A canalis nasolacrimalis. References. Basic: 1.Human Anatomy. In three volumes. Volume 2 / Edited by V.G. Koveshnikov. - Lugansk: LTD «Virtualnaya realnost», 2008. – 248p. 2.Human Anatomy. In three volumes. Volume 3 / Edited by V.G. Koveshnikov. - Lugansk: LTD «Virtualnaya realnost», 2009. – 384p. 3.Gray′s anatomy for students / Richard L. Drake, A. Wayne Vogl, and Adam W. M. Mitchell; illustrations by Richard M. Tibbitts and Paul E. Richardson; photographs by Ansell Horn. – 2nd ed. 2012 – 1103p. 4.Sobotta Atlas of Human Anatomy / Edited by R. Putz and R. Pabst, 14th ed. – Elsevier GmbH, Munich, 2008 . – 895p. 5.Clay JH, Pounds DM. 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Applied anatomy for clinical students and junior doctors: eleventh edition / Harold Ellis // Oxford, UK: Blackwell publishing. – 2006. – 455p. 6.Pocket atlas of Human Anatomy / Heinz Feneis, Wolfgang Dauber // Thieme, Stuttgart. – 2000. – 510p. 7. https://human.biodigital.com/ 8. http://anatom.ua/nomina-anatomica/