1、Organizations q中枢神经系统中枢神经系统Central nervous system (CNS)脑脑Brain脊髓脊髓Spinal cordq周围神经系统周围神经系统Peripheral nervous system (PNS)脑神经脑神经Cranial n. (12 pairs)脊神经脊神经Spinal n. (31 pairs)内脏神经内脏神经Visceral nervesMajor Divisions of the Central Nervous SystemqBrain 脑脑 Telencephalon 端脑端脑Diencephalon 间脑间脑Cerebellum 小脑
2、小脑Midbrain 中脑中脑Pons 脑桥脑桥Medulla oblongata 延髓延髓qSpinal cord 脊髓脊髓Brain stem脑干Major Divisions of the Peripheral Nervous System q脑神经脑神经Cranial nerves (12 pairs)q脊神经脊神经Spinal nerves (31 pairs) q内脏神经内脏神经Visceral nervesVisceral sensory nerveVisceral motor nervelSympathetic part 交感神经交感神经l Parasympathetic pa
3、rt 副交感神经副交感神经Cellular OrganizationqNeuron 神经元神经元 Cell body 胞体胞体Axon 轴突轴突Dendrites 树突树突 q Neuroglia神经胶质神经胶质 glial cell胶质细胞胶质细胞 Classification of NeuronqStructural classification双极神经元双极神经元 Bipolar neuronhas an axon and a dendrite假单极神经元假单极神经元 Pseudounipolar neuronhas a central branch and a peripheral b
4、ranch多极神经元多极神经元Multipolar neuronhas an axon and two or more dendritesClassification of NeuronsqFunctional classification感觉神经元感觉神经元 Sensory (afferent) neuron运动神经元运动神经元 Motor (efferent) neuron联络神经元联络神经元 Association neuronqReflex反射反射: a reaction of the organism by the nervous system in response to a st
5、imulusqReflex arc反射弧反射弧: has 5 basic components Receptor Sensory neurons CNS Motor neurons Effector Reflex and Reflex Arcq深反射（腱反射）深反射（腱反射）-膝跳反射膝跳反射 Basic Terminology in Nervous SystemIn the CNSqGray matter 灰质灰质: collection of nerve cell bodies and their dendrites, gray color during fresh conditionCo
6、rtex 皮质皮质: the outermost layer of gray matter in cerebrum and cerebellumNucleus神经核神经核: a collection ( group ) of cell bodies which have the same shape and function Basic Terminology in Nervous SystemIn the CNSqWhite matter 白质白质: collection of nerve fibers, white color during fresh conditionMedulla 髓
7、质髓质: a central core of white matter beneath the cortex of cerebrum and cerebellumFasciculus ( tract ) 纤维束纤维束: a bundle of nerve fibers which have the same origin, termination, pathway and function Basic Terminology in Nervous SystemqReticular formation 网状结构网状结构: an admixture of cross-crossing fibers
8、 with larger or smaller groups of nerve cells occupying the meshes Basic Terminology in Nervous SystemIn the PNSqGanglion 神经节神经节: a collection of neuronal cell bodies outside the CNS. eg. Spinal ganglion/gangliaqNerve 神经神经: a bundle of nerve fibers held together by connective tissue sheath. eg. Spin
9、al nerveZhaoxi Ding Department of Human AnatomyMedical School, Shandong UqPosition：Lies in the upper 2/3 of the vertebral canalContinuous above with medulla oblongata at level of foramen magnum Ends below at the lower border of L1 in adult or at level of L3 at birthqAbout 4045cm in length qWeights a
10、bout 30 g.Position of Spinal Cord qA long cylindrical structure and slightly flattened anteroposteriorlyq Two enlargementsCervical enlargement颈膨大颈膨大lcorresponds to the C4 - T1 segmentslsends fibers to supply the upper limbsLumbosacral enlargement腰骶膨大腰骶膨大lcorresponds to the L2 - S3 segmentslsends fib
11、ers to supply the lower limbs External Features of Spinal Cordq脊髓圆锥脊髓圆锥Conus medullaris-the lower pyramid end of spinal cordq终丝终丝Filum terminale-a delicate filament, about 20 cm in length, prolonged downward from the apex of the conus medullaris to the back of the first segment of the coccyx, contin
12、uous above with that of the pia mater. q马尾马尾Cauda equina-collection of roots and rootlets of spinal n. (from L2-5, S1-5,Co1) around the filum terminale below the conus medullaris. These fibers gradually declining in number further down as individual pairs leave the spinal column. Lumbar puncture (sp
13、inal tap)腰穿腰穿 External Features of Spinal CordFissure and sulciqAnterior median fissure 前正中裂前正中裂qPosterior median sulcus 后正中沟后正中沟qAnterolateral sulcus 前外侧沟前外侧沟 anterior (motor) roots emerge serially qPosterolateral sulcus 后外侧沟后外侧沟 posterior (sensory) roots enter spinal cord, each bear a spinal gangl
14、ion which constitutes the first cell-station of the sensory nervesqPosterior intermediate sulcus 后后中间沟中间沟 Segments of Spinal CordqA portion of the spinal cord that gives rise to a pair of spinal nerve constitutes a segment. qThere are 31 segments 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygealq
15、Relationship of spinal Cord Segments to Vertebral Numbers Relationship of spinal Cord Segments to Vertebral NumbersSpinal segmentsVertebral levels (spines)C1C4Lie opposite the corresponding vertebraeC5T4One lower in number than corresponding vertebraeT5T8Two lower in number than corresponding verteb
16、raeT9T12Three lower in number than corresponding vertebraeL1-L5T10T12S1-S5 and CoL1Relationship of spinal Cord Segments to Vertebral NumbersSpinal segmentsVertebral levels (spines)Upper cervical region (C1C4)= C1 C4Lower cervical and upper thoracic region (C5T4)1 = C4 T3Middle thoracic region (T5T8)
17、2 = T3 T6Lower thoracic region (T9T12)3 = T6 T9Lumber segments= T10 T12Sacral and coccygeal segments= L1Internal Structure of Spinal Cord qGray matter 灰质灰质qWhite matter 白质白质qCentral canal 中央管中央管qReticular formation网状结构网状结构 Gray Matter of Spinal Cord qAnterior horn (column) 前角前角(柱柱)qPosterior horn (c
18、olumn)后角后角(柱柱)qIntermediate zone 中间带中间带Lateral horn (column) 侧角侧角(柱柱) only present in the thoracic and upper lumber segments of the spinal cord (T1-L3) qgray commissures灰质连合灰质连合 Anterior gray commissures 灰质前连合灰质前连合Posterior gray commissures 灰质后连合灰质后连合 Gray Matter of Spinal CordPosterior horn (column
19、):qMarginal layer缘层缘层(posteromarginal nucleus后角边缘核后角边缘核)qSubstantia gelatinosa 胶状质胶状质Situated at the apex of posterior horn throughout the length of spinal cordConcerns the sensations of pain and temperatureqNucleus proprius 后角固有核后角固有核Situated anterior to the substantia gelationnosa throughout the l
20、ength of spinal cordReceives fibers that are associated with the superficial sensesqNucleus thoracicus 胸核胸核 Situated at the base of posterior horn and extending from segments C8L3Associated with the deep senses(proprioceptive endings) Gray Matter of Spinal CordIntermediate zoneqIntermediaolateral nu
21、cleus中间外侧核中间外侧核 (lateral horn)Extents from segments T1L3, Containing sympathetic preganglionic neuronsqSacral parasympathetic nucleus 骶副交感核骶副交感核Extents from segments S2S4, Containing parasympathetic preganglionic neuronsqIntermediomedial nucleus中间内侧核中间内侧核 Throughout the length of spinal cordAssociat
22、ed with viscera afferent informationAnterior horn (column): q Two groups of nucleiMedial nuclear group内侧核群内侧核群: present in most segments of spinal cord, innervating axial musclesLateral nuclear group外侧核群外侧核群: present only in cervical and lumbosacral enlargements, innervating upper and lower limb mus
23、clesGray Matter of Spinal Cord Anterior horn (column): qTwo kinds of motor neurons -motor neuron: large multipolar neuron, innervates skeletal muscles, producing contraction of muscles-motor neuron: smaller multipolar neuron, innervates intrafusal muscle fibers of neuromuscular spindles, regulating
24、muscular tonusqInterneuron Renshaws cell: negative feedback mechanism Rexeds lamina 板层板层qPosterior horn is formed by lamina to ； qIntermediate zone corresponding to lamina ；qAnterior horn is composed laminae and ；qlamina is the gray matter surrounding the central canal.Important Subdivisions of Gray
25、 MatterRegion LaminaNucleusPosterior hornMarginal layerSubstantia gelatinosa, Nucleus propriusIntermediate zoneNucleus thoracicus (C8L3)Intermediolateral nucleus (T1L3)Sacral parasympathetic nucleus (S2S4)Intermediomedial nucleus Anterior hornMotor neuronWhite Matter of Spinal CordqWhite matter白质白质
26、contains three kinds of fibers: Ascending fibersDescending fibersFasciculus proprius固有束固有束 White Matter of Spinal CordAnterior funiculus前索前索 Lateral funiculus 外侧索外侧索Posterior funiculus后索后索Anterior white commissure白质前连合白质前连合Ascending TractsFasciculus cuneatus楔束楔束Posterior spinocerebellar tr.脊髓小脑后束脊髓小
27、脑后束Anterior spinocerebellar tr.脊髓小脑前束脊髓小脑前束Spinothalamic tract脊髓丘脑束脊髓丘脑束Fasciculus gracilis薄束薄束q Fasciculus gracilis薄束薄束Located in the whole posterior funiculus below T4 and only in the medial part above T4Arise from the spinal ganglia below segment T4 (central process of spinal ganglia) Terminate i
28、n Gracile nucleus in medulla oblongataConvey proprioceptive and fine touch sensation from lower part of trunk and lower limb on the same sideSpinal ganglion 1neuron Gracile nuclei 2neuron T4FGFGq Fasciculus Cuneatus楔束楔束Located in the lateral part of posterior funiculus above T4Arise from the spinal
29、ganglia above segment T4 (central process of spinal ganglia)Terminate in cuneate nucleus in medulla oblongataConvey conscious proprioceptive and fine touch sensation from upper part of trunk and upper limb on the same sideSpinal ganglion 1neuron cuneate nuclei 2neuron T4FCFGLower limbupper limbFasci
30、culus gracilisFasciculus cuneatusCortex of cerebrumdiencephalonMedial leminecusGracile and cuneate Nu.lClinical noteLoss of proprioceptive sensation on the same sideLoss of fine touch sensation on the same sideSensory dystaxia(Incoordination)感觉性共济失调感觉性共济失调q Spinothalamic tract脊髓丘脑束脊髓丘脑束Located in th
31、e Lateral and anterior funiculusArise from the neurons in contralateral laminae I,IVVII about 1-2 segment belowTerminate in Dorsal thalamusConvey pain, temperature and simple touch sensation of trunk and limbsSpinal ganglia1neuron Lamina, 2neuron VPL 3neurons ASTLSTlClinical note Analgesia and therm
32、o-anesthesia on the opposite side of the body (bellow the damaged segment )qSpinocerebellar tracts脊髓小脑束脊髓小脑束Located in the superficial part of lateral and anterior funiculiConvey unconscious proprioception from lower limb and lower portion of trunk on the same side to the cerebellumContain:lPosterio
33、r spinocerebellar tract脊髓小脑后束脊髓小脑后束lAnterior spinocerebellar tract脊髓小脑前束脊髓小脑前束qPosterior spinocerebellar tract脊脊髓小脑后束髓小脑后束Located in the posterior and superficial part of lateral funiculus above L3Arise from the nucleus thoracicus on homolateral sideTerminate in superior and inferior vermis of cereb
34、ellumConvey unconscious proprioception from lower limb and lower portion of trunk on the same sideSpinal ganglion 1neuron Nucleus Thoracicus2neuronqAnterior spinocerebellar tract脊脊髓小脑前束髓小脑前束Located anterior to the posterior spinocerebellar tract in the superficial part of lateral funiculusArise main
35、ly from the neurons in contralateral laminaTerminate in superior vermis of cerebellumConvey unconscious proprioception from lower limb and lower portion of trunk on the opposite sideSpinal ganglion 1neuronLamina -2neuron Ascending tractsTract Site of originFuniculus TerminationFunction Fasciculus gr
36、acilisSpinal ganglia below segment T5Posterior Gracile nucleus Conscious proprioceptive (vibratory sense, and muscle joint sense) and fine touch sensation of trunk and limbsFasciculus cuneatusSpinal ganglia above segment T4Cuneate nucleusPosterior spinocerebellar tractHomolateral nucleus thoracicusL
37、ateral Cerebellum Unconscious proprioception from lower limb and lower portion of trunkAnterior spinocerebellar tractContralateral Laminae Spinothalamic tractLaminae , Lateral and anteriorDorsal thalamusPain, temperature and crude touch sensation of trunk and limbs上行传导束名称 起位置 止功能薄束T5以下的脊神经节后索 薄束核传导同
38、侧躯干和肢体的本体感觉（肌、腱、关节的位置觉、运动觉和震动觉）和精细触觉楔束T4以上的脊神经节楔束核脊髓小脑后束同侧胸核外侧索小脑下肢和躯干下部的非意识性本体感觉脊髓小脑前束对侧板层脊髓丘脑束板层,外侧索和前索背侧丘脑痛、温觉、粗触觉Descending TractsLateral corticospinal tract皮质脊髓侧束皮质脊髓侧束Anterior corticospinal tract皮质脊髓前束皮质脊髓前束 Rubrospinal tract红核脊髓束红核脊髓束 Vestibulospinal tract前庭脊髓束前庭脊髓束Reticulospinal tract网状脊髓束网状
39、脊髓束Medial longitudinal fasciculus内侧纵束内侧纵束 Tectospinal tract顶盖脊髓束顶盖脊髓束q Corticospinal tracts皮质脊髓束皮质脊髓束Arise from the pyramidal neurons in cerebral cortexLateral corticospinal tract皮质脊髓侧束皮质脊髓侧束Anterior corticospinal tract皮质脊髓前束皮质脊髓前束Anterolateral tract of BarneqLateral corticospinal tract皮质脊髓侧束皮质脊髓侧束L
40、ocated in deep part of lateral funiculusArise from the pyramidal neurons in contralateral cerebral cortex through the decussation of pyramid tractFibres arrangement lsuperficial to profound S,L,T,CTerminate in Laminae of anterior horn, C(55%),T(20%),LS(25%)Convey motor signal to control Voluntary mo
41、vement (muscles of the limbs)Clinical notes disability of voluntary movement( paralysis) q anterior corticospinal tract皮质脊髓前束皮质脊髓前束Located in medial part of anterior funiculusArise from the pyramidal neurons in contralateral cerebral cortex through the decussation of pyramid tractTerminate in Lamina
42、e on both anterior horn Convey motor signal to control voluntary movement(muscles of the trunk) Descending tractsTract Site of originFuniculus TerminationFunction Lateral corticospinal Cerebral cortexLateral Laminae anterior hornVoluntary movementAnterior corticospinalCerebral cortexAnterior Rubrosp
43、inal Red nucleusLateral Laminae Facilitates activity of flexor musclesVestibulospinal Homolateral vestibular nucleiAnteriorLaminae Facilitates activity of extensor musclesReticulospinal Reticular formationAnterior and lateral Laminae Voluntary movementMedial longitudinal fasciculusVestibular nucleiA
44、nteriorLaminae Coordinate neck with eye movementTectospinal Superior colliculusAnteriorLaminae Fasciculus propriusSpinal cordAnterior, lateral and posteriorSpinal cordIntrinsic reflex mechanism of spinal cord 下行传导束下行传导束名称起位置 止功能 皮质脊髓侧束 大脑皮质外侧索板层 前角随意运动皮质脊髓前束大脑皮质前索 红核脊髓束红核外侧索板层兴奋屈肌前庭脊髓束同侧前庭神经核前索板层兴奋伸
45、肌网状脊髓束网状结构前索和外侧索 板层 协调随意运动内侧纵束前庭神经核前索板层协调头颈部和眼的运动顶盖脊髓束中脑上丘前索板层 固有束脊髓前索、外侧索、后索脊髓脊髓节段内和节段间的联络 Main functions of spinal cordq Conduction of excitations传导传导q Reflex activity反射反射Complete spinal cord transection脊髓全横断脊髓全横断qThis transection results in complete loss of all sensibility and voluntary movement
46、below the level of the lesion.Hemisection of the cord脊髓半横断脊髓半横断qIpsilateral loss of tactile discrimination and of vibratory and proprioceptive sensations below the level of the lesion.qIpsilateral spastic paralysis below the level of the lesion.qContralateral loss of pain and temperature sensations
47、below the level of the lesion. This is due to destruction of the crossed lateral spinothalamic tracts on the same side of the lesion. Because the tracts cross obliquely, the sensory loss occur two or three segments below the lesion distally.Poliomyelitis脊髓灰质炎脊髓灰质炎qPoliomyelitis is an acute vriral in
48、fection of the neurons of the anterior gray columns of the spinal cord.qFollowing death of themotor nerve cells there is paralysis and wasting of the muscles.Syringomyelia 脊髓空洞症脊髓空洞症qLoss of pain and temperature sensations on dermatomes on both sides of the body related to the affected segments of t
49、he cord. qThis loss commonly has a shawl-like distribution, caused by the interruption of the lateral spinothalamic tracts as they cross the midline in the anterior gray and white commissures.练习题练习题简答：1 试述脊髓的位置和外形2 试述脊髓灰质和白质的分部。3 试述下列传导束的起止、功能、在脊髓内的位置（行程）：薄束、楔束、脊髓丘脑束、皮质脊髓侧束、皮质脊髓前束4 脊髓损伤的病例分析名词解释脊髓圆锥、终丝、马尾、脊髓节段q掌握神经系统的区分。掌握神经系统的区分。 q掌握神经系统的常用术语。掌握神经系统的常用术语。 q掌握脊髓的位置、外形特点、脊髓节段及其与椎骨掌握脊髓的位置、外形特点、脊髓节段及其与椎骨的对应关系。的对应关系。q掌握脊髓横切面上灰、白质的配布及各部的名称。掌握脊髓横切面上灰、白质的配布及各部的名称。q掌握脊髓灰质的主要核团的位置及功能性质。掌握脊髓灰质的主要核团的位置及功能性质。q掌握脊髓主要上行纤维束（薄束、楔束、脊髓丘脑掌握脊髓主要上行纤维束（薄束、楔束、脊髓丘脑束）和下行纤维束（皮质脊髓束）的位置和功能。束）和下行纤维束（皮质脊髓束）的位置和功能。
