Human anatamy
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median sulcus: longitudinally limiting sulcus: lateral to median sulcus. medial eminence: between two sulcuses above. v  estibular area: triangular area lateral to limiting sulcus, overlying nucleus of vestibular n.
acoustic tubercle: on lateral angle of vestibular trigone, overlying posterior cochlear nucleus. hypoglossal trigone: on medial eminence below medullary striae, overlying hypoglossal nucleus (superomedially). vagal trigone: inferolaterally, overlying dorsal vagal nucleus. postrema and locus ceruleus facial colliculus: a round swelling on medial eminence above medullary striae, overlying abducent nucleus. Ⅳ）The Fourth Ventricle It lies behind the pons and the upper half of the medulla oblongata, and in front of the cerebellum. The roof is toward the cerebellum, and the floor is rhomboid fossa. This ventricle contains cerebrospinal fluid, which communicates with midbrain aqueduct and central canal. s a anterior medullary velum r posterior part choroids tela of the fourth ventricle highly vascular tufts of pia matter, producing cerebrospinal fluid. t ↓ subarachnoid space two lateral apertures: on tip of each lateral recess. Ⅴ）External Features of Midbrain It is a short part of brain stem, located between the optid tract of diencephalons above and the upper margin of pons below. Midbrain aqueduct passes through its centre. 1. Ventral surface
2. Dorsal surface s  uperior colliculus: (visual reflex centre) brachium of superior
Quadrigeminal body: colliculuslateral geniculate body inferior colliculus: (audiroty reflex centre) brachium of inferior colliculusmedial geniculate body Ⅱ. Arrangement of Cranial Nerve Nuclei in Brain Stem The cranial nerve nuclei are located in the dorsal portion of brain stem. They arrange as following from midline to lateral: Somatic motor nucleivisceral motor nucleivisceral sensory nucleisomatic sensory nuclei. In the brain stem, the limiting sulcus divides sensory and motor cranial nerve nuclei. The cranial nerve motor nuclei are medial to the limiting sulcus, and the cranial nerve sensory nuclei are lateral to the limiting sulcus. The functional components of cranial nerve nuclei are: 1. Somatic motor nuclei (general)
in midbrain trochlear nucleus abducent nucleus----in pons hypoglossal nucleus----in medulla oblongata 2. Special visceral motor nuclei m  otor trigeminal nucleus----in pons
facial nucleus----in pons a  mbiguous nucleus
in medulla oblongata accessory nucleus 3. General visceral motor nuclei p arasympathetic mucleus of oculomotor nerve----in midbrain
superior salivatory nucleus----in pons i nferior salivatory nucleus
in medulla oblongata dorsal vagal nucleus 4. Visceral sensory nuclei (general and special) Solitary nucleus-in pons and medulla oblongata 5. General somatic sensory nuclei t rigeminal mesencephalic nucleus----in midbrain
trigeminal pontine nucleus----in pons trigeminal spinal nucleus----in pons and medulla oblongata 6. Special somatid sensory nuclei v estibular nucleus
in pons and medulla oblongata cochlear nucleus Ⅲ. Internal Structure of Medulla Oblongata The medulla oblongata can be divided into two parts, the upper and lower. The structures of the lower part are almost the same as those in spinal cord, but the strutures in the upper part are changed. 1. Edcussation of pyramids 2. Decussation of medial lemniscus 3. Appearance of inferior olivary nucleus and inferior cerebellar peduncle 4. Enlargement of central canal to form the fourth ventricle floor Ⅰ）Decussation of Pyramids c  orticonuclear tract: hypoglossal nucleus and lower part of facial nucleus receive the fibres only from contralateral corticonuclear tract.
p  yramids tract ---------------lateral corticospinal tract
crossed
corticospinal tract ---------------anterior corticospinal tract uncrossed Ⅱ）Decussation of Medial Lemniscus ipsilaterally Gracile and cuneate fascidulus----------------gracile and cuneate nucleus ( in medulla sending out fibres oblongata) --------------------decussation of medial lemniscusmedial lemniscusdorsal thalamus. Ⅲ）Inferior Olivary Nucleus and Infeior Cerebellar Peduncle o inferior cerebellar peduncle posterior spinocerebellar tract Ⅳ）Nuclei of Cranial Nerves 1. Hypoglossal nucleus It is located in both sides of the midline, underneath the hypoglossal trigone. The mucleus only receives the contralateral fibres from corticonuclear tract, and innervates the muscle of tongue. 2. Nucleus of accessory neve
3. Nuclei of vagal nerve 1) Dorsal vagal nucleus: located underneath vagal trigone, lateral to hypoglossal nucleus; innervating many cervical, thoracic and abdominal viscera. 2) Solitary nucleus: located dorsolateral to dorsal vagal nucleus; trceiving the fibres from all cervical, thoracic and abdominal mucous membrane. 3) Ambiguous nucleus: placed deeply in reticular formation; giving rise to the fibres to pharyngeal and laryngeal muscles. 4) Trigeminal spinal nucleus: lying on medial side of spinal tract; receiving impulse from posterior wall of external acoustic meatus. 4. Nuclei of glossopharyngeal nerve 1) Ambiguous nucleus: giving rise to the fibres to stylopharyngeal m. 2) Solitary nucleus: srceiving impulse from pharynx, auditory tube and posterior 1/3 of tongue (general visceral sense and gustatory sense). 3) Infeiror salivatory nucleus: to parotid gland. 4) Trigeminal spinal nucleus: collecting the fibres from skin of ear. Ⅳ. Internal Structure of Pons d two parts ventral portion----basilar portion The anterior margin of the trapezoid body is the boundary zone between the ventral and dorsal portion. The muclei of CN Ⅴ, Ⅵ, Ⅶ, Ⅷ are tound in pons. Ⅰ）Basilar Portion 1. Pyramidal tract c corticonuclear tract 2. Corticopontine tract: arising from the cells in frontal, parietal, temporal and occipital regions of cerebral cortex; and terminating in pontine nuclei ispilaterally. 3. Pontine nuclei: comprising all the masses of neurons scattered on this part; the fibres from these nuclei form middle cerebellar peduncle. They relay impulses from the cerebral cortex to the cerebellum. Ⅱ）Pontien Tegmentum 1. Cochlear nuclei (Dorsal and ventral cochlear nuclei): located on lateral surface of inferior cerebellar peduncle; concerning with hearing. sending out fibres Fibres from cochlear n. dorsal and ventral cochlear nuclei------------------------crossing to turning upward opposite sidetrapezoid body--------------------lateral lemniscusinferior colliculusmedial geniculate bodycerebral cortex. 2. Vestibular nuclei: four in number (inferior, superior, medial an lateral); underneath vestibular trugone; concerning with equilibrium sense. s Fibres from vestibular n. vestibular nucleus------------------- medial longitudinal tract the fibres to cerebellum 3. Nuclei of facila nerve 1) Facial nucleus: lying on dorsolateral to superior olive nucleus; innervating muscles of facial expression. u lower part: receiving fibres from corticonuclear tract of opposite side only;innervating muscles below palpebral fissure. 2) Superior salivatory nucleus: in the lateral of reticular formation; controlling the secretion of submandibular gland, sublingual gland, lacrimal gland and glands in mucous membrane of nose and mouth. 3) Solitary nucleus: concerning with the taste in anterior 2/3 of tongue. 4. Abducent nucleus: located underneath facial colliculus; innervating lateral rectus m. 1) Motor trigeminal nucleus: located medial to rootlet of trigeminal n. and dorsolateral to reticular formation; innervating m. of mastication. 2) Trigeminal pontine nucleus: lying lateral to motor trigeminal nucleus; conceying impulse of touch sense from skin and mucous membrane of face and forehead. 3) Trigeminal spinal nucleus: a continuation of trigeminal pontine nucleus; conveying the impulse of pain and thermal sense in skin and mucous membrane of face and forehead. 4) Trigeminal mesencephalic nucleus: lying near lateral margin of central grey matter; conveying proprioceptive impulses from teeth, hard palate, m. of mastication, and joint capsules. Ⅴ. Internal Structure of Midbrain
c ascending tract
p base of cerebral peduncle corticonuclear tract Ⅰ）Tectum 1. Superior colliculus: consisting of several layers of grey and white matter, a visual reflex centre. O superior colliculustectospinal tractmotor nucleus in brain stem, Retinaoptic tract anterior horn of spinal cordresulted in movements of head and eyes in response to visual and auditory stimulus. 2. Inferior colliculus: nucleus of inferior colliculus, auditory reflex centre. C inferior colliculusbrachium of inferior colliculusmedial geniculate Lateral lemniscus bodysuperior colliculustectospinal tractmotor nucleus in brain stem and spinal cordreflex in response to auditory stimulus. Ⅱ）Tegmentum 1. Central grey matter 1) Nuclei of oculomotor nerve
2) Trochlear nucleus: dorsal to medial longitudinal fasciculus; their fibres decussating completely in anterior medullary velum; innervating superior oblique m. 2. Red nucleus: ovoid mass in centre of tegmentum and dorsomedial to substantia nigra. Cerebral and cerebellar cortexred nucleusrubrospinal tractfacilitating flexor motor neurons. Ⅲ）Substantia Nigra A lamina of grey matter containing numerous, deeply pigmented nerve cells; lying between tegmentum and base of cerebral peduncle; extending through the whole length of midbrain and subthalamic region; grat development in man. Ⅳ）Base of Cerebral Peduncle It is the most ventral part of midbrain. f c occipitopontine tract (lateral 1/5) temporopontine p (middle 3/5) corticonuclear tract Ⅵ. Reticular Formation in Brain Stem It has long been recognized that scattered among the more conspicuous fibre bundles and nuclei of the brain stem are extensive field of intermingled grey and white matter collectively termed the reticular formation. Ⅶ. Cerebellum The cerebellum lies in the posterior cranial fossa, and is connected with the dorsal surface of brain stem by three cerebellar peduncles (superior, middle and inferior). It consists of two cerebellar hemispheres joined by a narrow median strip, the cerebellar vermis. Ⅰ）Subdivision of Cerebellum 1. Three lobes depending on the groove and fissure on its surface. f locculi (flocculus)
f  locculonodular lobe nodule
(inferior surface) peduncle of flocculi anterior lobe (prior to primary fissure) posterior lobe (between primary fissure and posterolateral fissure) Three parts on its development and connection of afferent fibres. a  rchicerebllum: viz. flocculonodular lobe, the oldest part; relating to vestibular nerve and nuclei; maintaining equilibrium.
paleocerebellum: including anterior lobe, pyramid of vermis and uvula of vermis in posterior lobe; receiving fibres from anterior and posterior spinocerebllar tracts; regulating muscular tone. neocerebellum: the newest and largest part; including posterior lobe except pyramid of vermis and uvula of vermis; connecting with cerebral cortex through middle cerebellar peduncle; coordinating skilled movements initiated at cortical level. Cerebellar tonsils are two elevated masses on both sides of the uvula of vermis, nearby the foramen magnum. Ⅱ）Internal Structures of Cerebellum 1. Cerebellar cortex: It is a superficial grey matter, which surrounds the white matter called medullary body. 2. Cerebellar nuclei d entate nucleus: the largest one close to vermis.
e mboliform nucleus
medial to dentate nucleus. globose nucleus fastigial nucleus: mear midline above roof of the fourth ventricle. Ⅲ）Fibrous Connection 1. Vestibulocerebellum (Archicerebellum) inferior cerebellar peduncle Vestibular nucleus of merves--------------------------------------archicerebellum---------------- e - fastigial nucleus---------------------- cerebellar peduncle reticular formationreticulospinal tract. 2. Spinocerebellum (Paleocerebellum) superior and inferior Anterior and posterior spinocerebellar tract-----------------------------paleocerebellum------ cerebellar peduncle i f efferent fibres reticular formation. - ------------------------------------------------------ globose nucleus r --------------------- reticular formationreticulospinal tract. 3. Pontocerebellum (Neocerebellum) middle cerebellar piduncle Corticopontil tractpontil nucleus---------------------------------neocerebellum----------------- efferent fibres superior cerebellar peduncle --------------------dentate nucleus------------------------------------ventrolateral nucleus of dorsal (decussation) thalamussomatomotor area. Ⅷ. Diencephalons The diencephalons is almost entirely surrounded by the hemispheres of the cerebrum, and consists of five parts, viz. the epithalamus, thalamus (dorsal thalamus), hypothalamus, subthalamus, metathalamus. Ⅰ）Esternal Features of Diencephalon 1. Dorsal thalamus (Thalamus) They are two oval grey masses. The third ventricle is a space just between two dorsal thalamus. a  nterior tubercle of thalamus: amarrow eminence in anterior end of dorsal surface.
pulvinar: elevation in posterior end. hypothalamic sulcus: from interventricular foramen to midbrain aqueduct, us a division between thalamus and hypothalamus. intermediante mass of dosal thalamus: trey matter connecting two thalamus, dorsal to hypothalamic sulcus. medullary stria and terminal stria 2. Metathalamus It lies inferolateral to pulvinar. brachium of inferior colliculus m edial geniculate body-----------------------------------inferior colliculus (auditory sense)
brachium of superior colliculus lateral geniculae body --------------------------------------superior colliculus (visual sense) 3. Epithalamus It lies around the roof of the third ventricle.
4. Hypothalamus It is situated below hypothalamic sulcus, and forms the side wall of the lower part of the third ventricle. a ↓ cinereous tuberinfundibulumhypophysis posterior mammillary body 5. The third ventricle It is a median sagittal fissure just between two dorsal thalamus. a posterior: passing to midbrain aqueduct roof: choroids tela, passing to lateral ventricle through interventricular foramen. floor: mammillary body, cinereous tuber, infundibulum, optic chiasm. Ⅱ）Internal Structures of Diencephalon 1. Dorsal thalamus and metathalamus Dorsal thalamus is an ovary grey mass medial to the internal capsule and lateral to the third ventricle. 1) Internal medullary lamina “Y” of thalamus anterior nuclear group medial muclear group (dorsomedial nucleus) d d pulvinar
l ateral ventral anterior nucleus
nuclear group ventral lateral nucleus v 2) Nucleus m interalaminar nucleus special relay nucleus: ventral layer of lateral nuclear group, medial and lateral geniculate bodies. association nucleus: medial nuclear group, dorsal layer of lateral nuclear group, anterior nuclear group. 3) Special relay mucleus ①Ventral anterior and ventral lateral nuclei They connect the xomatic motor area of cerebral cortex with cerebellar cortex. ②Ventral posterior nucleus m spinothalamic tract t gustatory fibres ③Medial and lateral geniculate bodies They are the relay nuclei of auditory and visual pathways. 2. Enpithalamus habenularnucleus 3. Subthalamus s red nucleus substantia nigra 4. Hypothalamus s  upraoptic nucleus: dorsal to optic chiasm.
paraventricular nucleus: close to the third ventricle . nucleus of mammillary body: in mammillary body. acruate (infundibular) nucleus: near infundibulum. Ⅸ. Telecephalon The telecephalon comprises mainly two large cerebral hemispheres, which are almost completely separated by the longitudinal cerebral fissure. At the bottom of this fissure, there is a large bundle of transverse fibres, the corpus callosum, which crosses between the two hemispheres. The transverse cerebral fissure intervenes between the hemispheres and the cerebellum. c b asilar nucleus
medullary centre---white matter lateral ventricle g  yrus (gyri): upfolds on surface of hemisphere.
fissures (sulcus or sulci): downfolds on surface of hemisphere. Ⅰ）External Features of Telecephalon s uperolateral surface
s in ferior (basilar)surface l ateral sulacus
sulci or fissures central sulcus parieto-occipital sulcus preoccipital notch f rontal lobe
parietal lobe lobes occipital lobe temporal lobe insula 1. Superolateral surface 1) Frontal lobe
p central sulcus precentral gyrus: between precentral and central sulcus superior and inferior frontal sulcus: prior to precentral sulcus parallel. superior, middle and inferior frontal gyrus 2) Parietal lobe postcentral sulcus: parallel to central sulcus. postcentral gyrus: between central and postcentral sulcus. interparietal sulcus: parallel to upper margin of hemisphere. superior parietal lobule s  upramarginal gyrus
inferior parietal lobule angular gyrus 3) Temporal lobe s uperior and inferior temporal sulcus
superior, middle, inferior temporal gyrus transverse temporal gyrus: two short gyri 4) Occipital lobe: irregular sulci and gyri. 5) Insula: There are shorter sulci. 2. Medial and inferior surface 1) Inferior surface of frontal lobe o orbital gyrus olfactory tract olfactory bulb olfactory trigone anterior perforated substance 2) Medial surface of parietal lobe patacentral lobule: extension of precentral and postcentral gyri. 3) Inferior and medial surface of temporal lobe o inferior medial occipitotemporal gyrus lateral occipitotemporal gyrus c rhinal sulcus
medial uncus (unci) hippocampal sulcus dentate gyrus hippocampus 4) Medial surface of occipital lobe c alcarine sulcus: arcuating posteriorly.
cuneus lobe: between calcarine and parieto-occipital sulci. lingual gyrus: inferior to calcarine sulcus. 5) The other sulci and gyri s cingulate sulcus cingulate gyrus Ⅱ）Internal Structures of Telecephalon 1. Lateral ventricle It lies within the cerebral hemisphere, contains cerebrospinal fluid which passes to the third ventricle by the interventricular foramen. c entral part----lying in parietal lobe
four anterior horn----extending into frontal lobe parts posterior horn----extending into occipital lobe
2. Basilar nucleus The group of nucleus lies near the floor of the cerebral hemisphere, deep in the white matter. h c  audate nucleus body meostriatum
tail
putamen corpus striatum lenticular nucleus pallid globe----paleostriatum claustrum: between insula cortex and lenticular nucleus. amyglaloid body: deep to uncus, anterior end of inferior hon of lateral ventricle. The function of corpus striatum is mainly concerned with the regulation of movement. 3. Cerebral cortex The cerebral cortex consists of archicortex, paleocortex and niocortex. Brodmann’s map was published in 1909 and consists of approximately 50 areas. 1) Somatic motor area Ⅰ ① Lying precentral gyrus and anterior portion of paracentral lobule. ② Receiving fibres from postcentral gyrus, ventrolateral nucleus, ventral anterior nucleus and ventral posterolateral nucleus. ③ Sending out fibres to form pyramidal tract. ④ Controlling voluntary movements of opposite side of body. ⑤ Characteristics: p representation appears inverted, such as head and neck inferiorly, following hand. Arm, trunk and thigh; but head and face are upright. size of cortical area for a particular part of body is determined by the functional importance and complexity fo the part. 2) Somatic sensory area Ⅰ ① Lying postcentral gyrus and posterior portion fo paracentral lobule. ② Receiving fibres from ventral posterior nucleus of dorsal thalamus for pain, thermal, tactile (touch), pressure, position, movement sense of opposite side of body. ③ Characteristics: i precise functional representation. size of cortical area depends on functional important and sensitivity of the sense region. 3) Visual area ① Lying medial surface of occipital lobe around calcaren sulcus (adjacent portion of cuneus lobe and lingual gyrus). ② Receibing fibres from lateral geniculate body. ③ The left half of visual field is represented in the visual area of right hemisphere, and vice versa. 4) Auditory area ① Lying transverse temporal gyrus. ② Receiving fibres from medial geniculate body. ③ Representing bilaterally. 5) Language areas (Speech areas) The hemisphere relating to language function is termed dominant hemisphere, mostly in the left hemisphere because the right handed-persons are much more than the left ones. ① Motor speech area: in posterior portion of inferior frontal gyrus. ② Auditory speech area: in posterior portion of superior temporal gyrus. ③ Writng area: in posterior portion of middle frontal gyrus. ④ Visusl speech area: in angular gyrus. 4. Medullary centre of hemisphere 1) Commissural fibres They interconnect corresponding area in the opposite hemispheres. ① Corpus callosum It transverse the floor of cerebral longitudinal fissure and connects the cortex of two cerebral hemisphere. It includes four parts, viz. rostrum, genu, body, splenium, from before backwards. ② Anterior commissrue It is H-shaped arcuate fibrous bundles anterior to fornix. ③ Fornix and fornix commissure They are bilateral C-shaped white fibres originating from fimbria of hippocampus to nucleus of mammillary body. 2) Association fibres They interconnect different cortical area in the came hemisphere. u superior longitudinal fasciculus inferior longitudinal fasciculus 3) Projecting fibres They are referred to ascending and descending fibres connecting cerebral cortex and subcortical structures, such as spinal cord and brain stem. Internal capsule lies between caudate nucleus, dorsal thalamus medially and lentiform nucleus laterally, and is a “><” shaped layer of white matter. The division and its fibres are as following. ① Anterior limb of internal capsule It lies between caudate nucleus and lentiform nucleus. f containing anterior thalamic radiation (thalamocortical fibres) Posterior limb of internal capsule ② Posterior lim of internal capsule It lies etween thalamus and lentiform mucleus. Its three parts and passing fibres are:
c corticorubral tract
such as, trigeminal lemnisus, spinothalamic lemniscus, medial lemniscus) o retrolenticular part parietopontine tract occipitopontine tract a temporopontine tract ③ Genu of internal capsule It is an angle area between anterior and posterior limbs, and contains corticonuclear tract. Ⅲ）Limbic System
Limbic lobe adds cortical and subcortical structures closely related to it, such as amygdaloid body, septal area, sepptal nucleus, hypothalamus, epithalamus, anterior nucleus of dorsal thalamus, tegmentum of midbrain, then limbic system is formed. Section 3 The Conduction Pathways of the Brain and Spinal Cord They are the routes formed by chains of neurons, through which sensory awareness reaches the cerebral cortex and a motor response is initiated. The conduction pathways are commonly classified into ascending (sensory) and descending (motor) ones. Ascending pathways conduct impulse of various receptors of body to cerebral cortex or other higher centres of brain, and enable the individual to be conscious of his environment. They generally involve three orders of neurons.
Descending pathways bring cerebral cortex and other subcortex into communication with effector tissues (such as muscles and glands), through anterior horn of spinal cord. Thus the body is able to respond to environment change. Two orders of neurons are usually involved. Ⅰ. The Conscious Deep Sensory Pathway m ---------------------------------------------------------- joints, skin. accompanying corresponding spinal nerve 1 2 c -  ------------------------------------------------------------------<·---------
entering posterior funiculus of spinal spinal ganglia cord as a garcile and cuneate gracile and cuneate (first order neuron) fasciculus through dorsal root of nucleus spinal cord (second order neuron) 3 d -----------------------------------<·------------------------------------------ ascending as medial lemniscus ventral posterolateral nucleus of dorsal thalamus (third order neuron) t ------------------------------------→ ②posterior part of paracentra lobule (thalamocortical tract) ③precentral gyrus Ⅱ）The Deep Sensory Pathway of Head and Face The exact route of this pathway is still unknown. Ⅱ. The Unconscious Deep Sensory Pathway Ⅰ）Posterior Spinocerebellar Tract 1 m p ressure receptors of lower limbs ---------------------------------------------
and lower part of trunk spinal nerve spinal ganglia 2 c ----------------<·---------------------------------→inferior cerebellar peduncle→ processes ipsilateral lateral funiculus thoracic nucleus →cortex of paleocerebellum Ⅱ）Anterior Spinocerebellar Tract 1 p l ower extremities and -----------------------------------------------------
lower part of trunk spinal nerve processes spinal ganglia 2 a ----<·-------------------------→superior cerebellar peduncle→cortex of paleocerebellum contralateral lateral funiculus × grey layer Ⅴ-Ⅶ of lumbar enlargement Ⅲ. The Superficial Sensory Pathway of Trunk and Limbs 1 s t runk and ------------------------------------------------------------------
extremities accompanying entering spinal cord through dorsa roots corresponding spinal ganglia spinal nerve 2 3
------<·---------------------------------------------------------<·--------- or cross one segment, spinothalamic tract cells of posterior ventral posterolateral nucleus horn (ⅠⅣⅤ) of dorsal thalamus ( ----------------------------→ posterior limb of internal capsule posterior part of paracentral lobule A hemisection of spinal cord would cause loss of pain and temperature sensation on the opposite side of the body below the section, since the fibres of lateral spinothalamic tract are crossed. Because the gracile and cuneate fasciculus as well as spinothalamic tract have the same function in touch sense, and because the latter crosses over in spinal cord, the former uncrossed, a hemisection of the spinal cord ont result in complete loss of the sensations of touch. Ⅳ. The Superficial Sensory Pathway of the Head and Face 1 2
s   kin, mucous peripheral processes central processes
o and face trigeminal nerve entering pons semilunar ganglion trigeminal pontine nucleus trigeminal spinal nucleus 3 c ------------------------------<·--------------------------------------------- trigeminal lemniscus posterior limb of internal capsule ventral posteromedial nucleus of dorsal thalamus ---------→lower part of postcentral gyrus
Visual field is the images of the objects in a visual space scope, which is divided into two part, the nasal half and temporal half. The retina itself also in cludes the nasal half and temporal half. 1 2 r  ----------------- -------------------<·------------optic nerve---
cone cells processes processes bipolar cells ganglion cells 3
------optic chiasm---------------------------------optic tract---------<·---------- nasal fibres of retina cross temporal fibres of retina uncross × lateral geniculate body optic radiation ----------------------------→both sides of calcarine sulcus (suneus lobe and lingual gyrus) posteror limb of internal capsule the impulse from upper half retina arrive the dorsal band of calcarine sulcus (cuneus lobe). The impulse from lower half retina arrive the ventral band of calcarine sulcus (lingual gyrus). The impulse from macula arrive the posterior portion of calcarine area. The impulse from peripheral retinal area end in the anterior portion of calcarine area.
p Cells of retina→optic nerve, optic chiasm, optic tract-----------------------<·------ through brachium of superior colliculus pretectal area
------<·-------------------------<·---------→ (regulating contraction of pupil) nerve ciliary muscle parasympathetic ciliary ganglion (regulating convexity of lens) oculomotor nucleus (Edinger-Westphal) Destruction (Inetrruption) analysis 1. Grossing fibres of optic chiasm: would cause blindness of two temporal visual field (bilateral or bitemporal hemianopsia). 2. Laeral (uncrossed) fibres of potic chiasm: would result in blindness of two nasal visual field (bimedial or binasal hemianopsia) . 3. Optic tract, lateral geniculate body, optic radiation, optic cortex on one side would cause blindness in the medial half visual field of one eye (destrcted side) and in the lateral half of the other one (undestructed side). 4. One optic nerve would result in blindness in the corresponding eye with loss of the papillary (light) reflex. Ⅵ. The Auditory Pathway 1 2 s -----------------·--------------------------------<·------- (Corti’s organ) processes cochlea nerve bipolar cells of dorsal and ventral cochlear spiral ganglion cochlear nuclei 3 t -  ------------------------------<·---------------------------------<·-----------
c inferior colliculus medial geniculate body
-------------------------------→transverse temporal gyrus posterior limb of internl capsule Ⅶ. Pyramidal System Two orders of neurons are primarily involved, the upper and lower efferent neurons. upper efferent hypoglossal nucleus, lower portion neurons corticonuclear tract of facial nucleus are controlled by p ·--------------------- others by bilateral corticonuclear tract. decussation of pyramid × p o (cortex) posterior limb of in spinal cord ×
l m -----------<·-----------→ facial m. ① laryngeal m. motor nucleus of cranial nerve pharyngeal m. lingual m.
- ② voluntary m. of trunk and extremities -----------------------<·----------------→ ③ cells of anterior horn of spinal cord Ⅷ. Extrapyramidal System Ⅰ）Concept and Composition It is a common name for all the structures which control voluntary muscle activities, except the pyramidal system. It mainly consists of cerebral cortex, corpus striatum, red nucleus, black substance, cerebellum, reticular formantion, vestibular nucleus. Ⅱ）Two Simple Descending Pathway 1. cerebral cortex
pons thalamus  
cerebellum 
red nucleus
spinal cord 2. cerebral cortex
corpus striatum ----→thalamus   
subthalamus 
black substance 
reticular formation
spinal cord Ⅲ）Two Systems and Four Tracts 1. Neostriatrum----pallid glaobe system 1) Cerebral cortex----corpus striatum----dorsal thalamus----cerebral cortex circle route. 2) Corpus striatum----black substance circle route 3) Pallid globe----subthalamus circle route 2. Corticopontocerebellar system cortex----pons----cerebellum----dorsal thalamus----cortex circle route 3. Four tracts R Rubrospinal tract Tectospinal tract Vestibulospinal tract Ⅳ）Function 1. Regulating muscular tone. 2. Maintaining the normal body posture (balance). 3. Coordinating muscular activities (precise motions). 4. Producing habitual and rhythmic movement. Section 4 The Meninges, Blood Vessels of Brain and Spinal Cord, as well as Cerebrospinal Circulation Ⅰ. The Meninges of Brain and Spinal Cord The brain and spinal cord are enclosed by three layers of membrane, the dura mater, arachnoid, pia mater, from external inwards. They protect and support the brain and spinal cord. Ⅰ）Dura Mater 1. Spinal dura mater It extends from the foramen magnum to the level of the second sacral vertebra, from which it tapers and forms a covering for the filum terminal of spinal cord. 1) Epidural space s l containing: loose conjunctive tissue, lymphatic vessels, fat, venous plexus, especially root of spinal nerve. Being not continuous with cranial cavity upward. 2) Subdural space s between spinal arachnoid 2. Cranial dura matter 1) Double layers: periosteal, meningeal. 2) Loosely contacting with skullcap: closely attached to base of skull. 3) Falx and tentorium formed by meningeal layer. c erebral falx: extending into cerebral longitudinal fissure.
cerebellar tentorium: between cerebral hemisphere and cerebellum. tentorial notch: anterior free margin of cerebellar tentorium. cerebellar falx: extending into two cerebellar hemisphere. 4) Dural venous sinus Lying between meningeal and peiosteal dura in some place. Characteristics: novalves, no smooth m., no contractivity. s  uperior sagitaal sinus: lying in superior convex border of cerebral falx.
inferior sagittal sinus: inferior concave border of cerebral falx. straight sinus: at the junction between cerebral falx and cerebellar tentorium. transverse sinus: in transverse sulcus, posterior margin of cerebellar tentorium. sigmoid sinus: in sigmoid sulcus. confluent sinus: at confluence of superior sagittal sinus and straight sinus. cavernous sinus: each side of sella turcica internal carotid a.
intrasinus abducent n. (CN Ⅵ) o lateral wall of sinus trochlear n. (CN Ⅳ) ophthalmic n. (CN Ⅴ1) maxillary n. (CN Ⅴ2)
The blood draning in dural venous sinus s i c i Ⅱ）Arachnoid
1. Spinal arachnoid s l subarachnoid space: spinal pia mater containing cerebrospinal fluid 2. Cranial arachnoid 1) Subdural space: between cranial dura mater and cranial arachnoid 2) Subarachnoid space ① Between cranial arachnoid and cranial pia mater ② Enlargement in some area
③ Arachnoid granulation: especially in superior sagittal sinus, allowing cerebrospinal fluid to be reabsorbed into dura venous sinus. Ⅲ）Pia Mater The pia mater is a delicate vascular membrane, and rich in nerves. It is closely attached to the surface of brain and spinal cord. 1. Spinal pia mater
2. Cranial pial mater The cranial pia mater combines its capillaries and ependymal cells to form the choroids tela of the ventricle. Folds of choroids tela form choroids plexuses, which produce cerebrospinal fluid. Ⅱ. The Blood Vessels of the Brain and Spinal Cord Ⅰ）The Arteries of Brain
two resource of diencephalon vertebral a. ----posterior 1/3 of cerebral hemisphere, brain stem, cerebellum, posterior part of diencephalon 1. Internal carotid artery Arising fom common carotid a. ascending to floor of skullcarotid canalcavernous sinusanterior clinoid process. 1) Posterior communicating a. ----communicating with posterior cerebral a. 2) Anterior choroidal a. ----forming arachnoid plexuses in lateral ventricle, supplying optic tract, internal capsule, base of cerebral peduncle and pallid globe. 3) Anterior cerebral a. a nterior communicating a.----connecting two anterior cerebral a. supplying medial surface of cerebral hemisphere anterior to parietooccipital sulcus, inferior surface of frontal lobe.
central branches----caudate nucleus, lenticular nucleus, internal capsule. 4) Middle cerebral a. ----supplying supralateral surface of hemisphere and insula. Central branch----caudate nucleus, lenticular nucleus, internal capsule. 2. Vertebral artery Arising from subcalvian a. transverse foramen of C1-6 vertebraeforamen magnumposterior cranial fossapontomedullary sulcusconfluence of two vertebral a. to form basilar a. basilar sulcussuperior border of pons. 1) Branches of vertebral a. ① Anterior and posterior spinal a. ----spinal cord. ② Posterior inferior cerebellar a. ----inferior surface of cerebellum, medulla oblongata. 2) Branches of basilar a. ① Anterior inferior cerebellar a. ----inferior surface of cerebellum. ② Labyrinthine a. ----inner ear. ③ Pontine a. ----pons. ④ Superior cerebellar a. ----upper part of cerebellum. ⑤ Posterior cerebral a. s central branches----dorsal thalamus, medial and lateral geniculate body, hypothalamus, subthalamus. taking part in arachnoid plexuses of lateral and the third ventricles 3. Cerebral arterial circle (Willis circle) a (beginning prat) posterior cerebral a. anterior communicating a. posterior communicating a. internal carotid a. (terminal part) It encircles the optic chiasm, cinereous tuber, mammillary body over sella turcica. Ⅱ）The Veins of Brain s great cerebral v. Ⅲ）The Vessels of Spinal Cord a nterior spinal a. v.
posterior spinal a. v. Ⅲ. The Circulation of Cerebrospinal Fluid 1. Cerebrospinal fluid (CSF) is formed by choroids tela the in lateral, the third and fourth ventricles. 2. Circulation Lateral ventricleinterventricular foramenthe third ventriclemidbrain aqueductthe fourth ventriclemedian and lateral apertures of the fourth ventriclesubarachnoid spacesarachnoid granulationssuperior sagittal sinusinternal jugular v.
The endocrine system consists of the endocrine glands and endocrine tissues. The endocrine glands have no ducts, therefore they are known as ductless glands, which have a rich supply of blood vessles and pass their secretions derectly into the vascular channels. The secretions are called hormones, which have special effects on the body. Ⅰ. The Shape and Location of Thyroid Gland It likes “H” shaped body. l (right and left) u -----→
Lower end: the sixth tracheal cartilage ring. isthmus: in front of 2~4 tracheal cartilage. Ⅱ. The Shape and Location of Parathyroid Gland They are four small yellowish ovoid or lentiform bodies. u Ⅲ. The Shape and Location of Suprarenal Gland They are a pair of small yelloweish-brown bodies, lying on medial part of superior end of each kidney, and behind the peritoneum. r left----crescent-like shape or semilunar shape Ⅳ. The Shape and Location of Hypophysis It is an ovary gland situated in the hypophyseal fossa of sphenoid body. a two parts neurohpophysis Ⅴ. The Shape and Location of Pineal Body It is an ovary body located in the posterosuperior to thalamus, attached the posterior part of the roof of the third ventricle by handle. Liu Zhiyu Directory: G2S -> eWebEditor -> uploadfile uploadfile -> Experiment Guide of Sectional Anatomy Edited by Li Zhenping Liu Shuwei Ding juan Shan Dong University School Of Medicine uploadfile -> Zen From Wikipedia, the free encyclopedia Jump to: navigation, search For other uses, see Zen uploadfile -> 外国文学作品欣赏 Edited By Zhu Farong Ding Liqun 主 编 朱法荣 副主编 丁立群 Shandong Agricultural University Download 0.6 Mb. Share with your friends:
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nterior part
yramidal tract
rontopontine tract (medial 1/5)
--------------------- emboliform nucleus superior cerebellar peduncle
orsal layer posterolateral nucleus
uscles, tendons, peripheral processes 
ross lateral lemniscus × colliculus
yramidal tract genu of internal capsule opposite corticonuclear tract; ①
recentral gyrus, anterior part corticospinal tract lateral corticospinal tract ②
f paracentral lobule anterior part of crossing segment by segment 
ower efferent neurons exteraocular m. 
culomotor n. (CN Ⅲ)
uperior sagittal sinus occipital sinus
nferior sagittal sinusstraight sinusconfluent transverse sigmoid internal jugular v. 
nferior petrosal sinus
pper end: midpart of thyroid cartilage.