神经系统总论、脊髓

1、Central nervous system (CNS) nBrain 脑脑 qTelencephalon 端脑端脑 qDiencephalon 间脑间脑 qCerebellum 小脑小脑 qBrain stem 脑干脑干 nMidbrain 中脑中脑 nPons 脑桥脑桥 nMedulla oblongata 延髓延髓 nSpinal cord 脊髓脊髓 Peripheral nervous system (PNS) nCranial n. (12 pairs) 脑神经脑神经 nSpinal n. (31 pairs) 脊神经脊神经 nVisceral n. 内脏神经内脏神经 qViscer

2、al sensory n. qVisceral motor n nSympathetic part 交感神经交感神经 n Parasympathetic part 副交感神经副交感神经 Cellular organization nNeurons 神经元神经元 qCell body 胞体胞体 qAxon 轴突轴突 qDendrites 树突树突 n Neuroglia glial cell胶质细胞胶质细胞 Structural classification nBipolar neuron 双极神经元双极神经元 has an axon and a dendrite nPseudounipolar

3、 neuron 假假 单极神经元单极神经元 has a central branch and a peripheral branch nMultipolar neuron多极神经元多极神经元 has an axon and two or more dendrites Functional classification nSensory (efferent) neuron 感觉神经元感觉神经元 nMotor (afferent) neuron 运动神经元运动神经元 nAssociation neuron 联络神经元联络神经元 nReflex: a reaction of the organism

4、 by the nervous system in response to a stimulus nReflex arc: has 5 basic components Receptor Sensory neurons CNS Moter neurons Effector Reflex and reflex arc Basic terminology in nervous system In the CNS nGray matter 灰质灰质: collection of nerve cell bodies and their dendrites, gray color during fres

5、h condition nCortex皮质皮质: the outermost layer of gray matter in cerebrum and cerebellum nWhite matter白质白质: collection of nerve fibers, white color during fresh condition nMedulla髓质髓质: a central core of white matter beneath cortex of cerebrum and cerebellum nNucleus神经核神经核: a collection ( group ) of ce

6、ll bodies which have the same shape and function nFasciculus 纤维束纤维束 ( tract ): a bundle of nerve fibers which have the same origin, termination, pathway and function nReticular formation 网状结构网状结构: an admixture of cross-crossing fibers with larger or smaller groups of nerve cells occupying the meshes

7、 In the PNS nGanglion 神经节神经节: a collection of neuronal cell bodies outside the CNS nNerve 神经神经: a bundle of nerve fibers held together by connective tissue sheath The Spinal Cord 脊髓脊髓 Position nLies in vertebral canal nContinuous above with medulla oblongata at level of foramen magnum nEnds below at

8、 lower border of L1 in adult; at birth at level of L3 External features nA long cylindrical structure and slightly flattened anteroposteriorly, nConus medullaris （脊髓圆锥）（脊髓圆锥） nFilum terminale （终丝）（终丝） nCauda equina （马尾）（马尾） nTwo enlargements Cervical enlargement （颈膨大）颈膨大）: corresponds to the C4 to t

9、he T1 segments Lumbosacral enlargement （腰骶膨大）（腰骶膨大）: corresponds to the L2 to the S3 segments Fissure and sulci nAnterior median fissure 前正中裂前正中裂 nPosterior median sulcus 后正中沟后正中沟 nAnterolateral sulcus 前外侧沟前外侧沟anterior (motor) roots emerge serially nPosterolateral sulcus 后外侧沟后外侧沟posterior (sensory)

10、roots enter spinal cord, each bear a spinal ganglion which constitutes the first cell- station of the sensory nerves Relationship of segments of spinal cord to vertebrae nA portion of the cord that gives rise to a pair of spinal nerve constitutes a segment. nThere are 31 segments 8 cervical 12 thora

11、cic 5 lumbar 5 sacral 1 coccygeal Relationship of segments of spinal cord to vertebrae Spinal segmentsVertebral levels (spines) Upper cervical region (C1C4)= C1 C4 Lower cervical and upper thoracic region (C5T4) 1 = C4 T3 Middle thoracic region (T5T8) 2 = T3 T6 Lower thoracic region (T9T12) 3 = T6 T

12、9 Lumber segments= T10 T12 Sacral and coccygeal segments= L1 Internal structures nCentral canal 中央管中央管 nGray matter qAnterior horn (column) 前角（柱）前角（柱） qPosterior horn (column)后角（柱）后角（柱） qIntermediate zone 中间带中间带 nLateral horn (column) 侧角（柱）侧角（柱） qAnterior gray commissures 灰质前连合灰质前连合 qPosterior gray

13、commissures 灰质后连合灰质后连合 nWhite matter qAnterior funiculus 前索前索 qlateral funiculus 外侧索外侧索 qPosterior funiculus 后索后索 qAnterior white commisure 白质前连合白质前连合 Posterior horn (column): nMarginal layer （缘层） nSubstantia gelatinosa （胶状质） nNucleus proprius （后角固有核） nNucleus thoracicus（胸核） in segments C8L3 Interme

14、diate zone nIntermediaolateral nucleus （中间外侧核）(lateral horn or column): lies in segments T1L3, containing sympathetic preganglionic neurons nSacral parasympathetic nucleus （骶副交感核）: lies in segments S2S4, containing parasympathetic preganglionic neurons nIntermediomedial nucleus （中间内侧核） : for sensati

15、on of viscera Anterior horn (column): contain motor neurons nThree kinds of neuron q-motor neuron: larger multipolar neuron, innervates extrafusal fibers of skeletal m., producing contraction of m. q-motor neuron: smaller neuron, innervates intrafusal fibers regulating muscular tonus qRenshaws cell:

16、 negative feedback mechanism nTwo groups of nuclei qMedial nuclear group: present in most segments of spinal cord, innervating axial muscles qLateral nuclear group: present only in cervical and lumbosacral enlargements, innervating limb muscles Rexeds lamina 板层板层 nposterior horn is formed by lamina

17、to ； nIntermediate zone corresponding to lamina ； nAnterior horn is composed laminae and ； nlamina is the gray matter surrounding the central canal. Important Subdivision of Spinal Cord Gray Matter Region LaminaNucleus Posterior hornMarginal layer Substantia gelatinosa , Nucleus proprius Intermediat

18、e zoneNucleus thoracicus (C8L3) Intermediolateral nucleus (T1L3) Sacral parasympathetic nucleus (S2S4) Intermediomedial nucleus Anterior hornMotor neuron ) White matter White matter contains three kinds of fibers: ascending, descending, and fasciculus proprius Ascending tracts Fasciculus gracilis（薄束

19、）（薄束） Fasciculus cuneatus （楔束）（楔束） Posterior spinocerebellar tract （脊髓小脑后束）（脊髓小脑后束） Anterior spinocerebellar tract （脊髓小脑前束）（脊髓小脑前束） Spinothalamic tract （脊髓丘脑束）（脊髓丘脑束） Ascending tracts Tract Site of originFuniculus TerminationFunction Fasciculus gracilis Spinal ganglia below segment T5 Posterior Grac

20、ile nucleus Convey proprioceptive and fine touch sensation of trunk and limbs Fasciculus cuneatus Spinal ganglia above segment T4 Cuneate nucleus Posterior spinocerebellar Homolateral nucleus thoracicus Lateral Cerebellum Unconscious proprioception from lower limb and lower portion of trunk Anterior

21、 spinocerebellar Contralateral Laminae Spinothalamic Laminae , Lateral and anterior Dorsal thalamus Pain, temperature and simple touch sensation of trunk and limbs Descending tracts Lateral 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

22、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） Fasciculus proprius （固有束）（固有束） Descending tracts Tract Site of originFuniculus TerminationFunction Lateral corticospinal Cerebral cortexLateral L

23、aminae anterior horn Voluntary movement Anterior corticospinal Cerebral cortexAnterior Rubrospinal Red nucleusLateral Laminae Excitatory of flexors Vestibulospinal Homolateral vestibular nuclei AnteriorLaminae Excitatory of extensors Reticulospinal Reticular formation Anterior and lateral Laminae Vo

24、luntary movement Medial longitudinal fasciculus Vestibular nuclei AnteriorLaminae Coordinate neck with eye movement Tectospinal Superior colliculus AnteriorLaminae Fasciculus proprius Spinal cordAnterior, lateral and posterior Spinal cordIntrinsic reflex mechanism of spinal cord Main functions of sp

25、inal cord n Conduction of excitations n Reflex activity Peripheral nervous system (PNS) nCranial n. (12 pairs) 脑神经脑神经 nSpinal n. (31 pairs) 脊神经脊神经 nVisceral n. 内脏神经内脏神经 qVisceral sensory n. qVisceral motor n nSympathetic part 交感神经交感神经 n Parasympathetic part 副交感神经副交感神经 Cellular organization nNeurons 神经元神经元 qCell body 胞体胞体 qAxon 轴突轴突 qDendrites 树突树突 n Neuroglia glial cell胶质细胞胶质细胞 Structural classification nBipolar neuron 双极神经元双极神经元 has an axon and a dendrite nPseudounipolar neuron 假假 单极神经元单极神经元 has a central branch and a peripheral branch nMultipolar neu