文本神經(jīng)病復件peripheral nervous system

1、The PeripheralNervous System Jing ZhaoEmail Department of Neurology Jinan Central Hospital Affiliated to Shandong University Anatomy and physiology Peripheral nervous system: the spinal cord and nerve structures located all soft outer membrane of the brain stem, spinal nerve spinal nerve root that i

2、s emitted from the ventral and dorsal spinal cord composed and sent from the brain stem outside the abdomen, excluding the olfactory nerve and the optic nerve.Spinal nervesPart of the peripheral nervous system31 pairs attach through dorsal and ventral nerve rootsLie in intervertebral foraminaSpinal

3、nervesDorsal roots sensory fibers arising from cell bodies in dorsal root gangliaVentral roots motor fibers arising from anterior gray column of spinal cordThe Peripheral Nervous SystemNervous structures outside the brain and spinal cordNerves allow the CNS to receive information and take actionFunc

4、tional components of the PNSSensory inputs and motor outputs categorized as somatic or visceralSensory inputs also classified as general or specialSensory Input and Motor OutputSensory (afferent) signals picked up by sensor receptors, carried by nerve fibers of PNS to the CNSMotor (efferent) signals

5、 are carried away from the CNS, innervate muscles and glandsDivided according to region they serveSomatic body regionVisceral body regionResults in four main subdivisionsSomatic sensoryVisceral sensorySomatic motorVisceral motorPNS Afferent DivisionAfferent (sensory) division transmits impulses from

6、 receptors to the CNS. Somatic afferent fibers carry impulses from skin, skeletal muscles, and jointsVisceral afferent fibers transmit impulses from visceral organs Types of Sensory and Motor InformationFigure 12.3SensoryGeneral somatic senses include touch, pain, vibration, pressure, temperaturePro

7、prioceptive senses detect stretch in tendons and muscle provide information on body position, orientation and movement of body in spaceSpecial Senses - hearing, balance, vision, olfaction (smell), gustation (taste)MotorGeneral somatic motorSignals contraction of skeletal musclesUnder our voluntary c

8、ontrol Visceral motorMakes up autonomic nervous system (ANS)Regulates the contraction of smooth and cardiac muscle, controls function of visceral organsANS has two divisionsParasympatheticSympatheticThe Autonomic Nervous System Effects of Sympathetic ActivationGeneralized response in crisesIncreased

9、 alertness/energyIncreased cardiovascular activityIncreased respiratory activityIncreased muscle toneNervesNerves cable like organs in the PNSConsists of numerous axons wrapped in connective tissueEndoneurium layer of delicate connective tissue surrounding the axonPerineurium connective tissue wrapp

10、ing surrounding a nerve fascicle 3 Nerve fascicles groups of axons bound into bundles4 Epineurium whole nerve is surrounded by tough fibrous sheathAxon is surrounded by Schwann cellsCranial NervesAttach to the brain and pass through foramina of the skullNumbered from IXIICranial nerves I and II atta

11、ch to the forebrainAll others attach to the brain stemPrimarily serve head and neck structuresThe vagus nerve (X) extends into the abdomenThe 12 Pairs of Cranial NervesFigure 14.5Table 14.3 (1 of 12)Olfactory Nerves (I)Sensory nerves of smellolfactory nerve (I)Olfactory bulbOlfactory tractOptic nerv

12、e (II)Optic chiasmaOptic tractOculomotor nerve (III)Trochlear nerve (IV)Trigeminal nerve (V)Abducens nerve (VI)CerebellumMedullaTable 14.3 (2 of 12)Optic Nerve (II)Sensory nerve of visionFilaments ofolfactory nerve (I)Olfactory bulbOlfactory tractOptic nerve (II)Optic chiasmaOptic tractOculomotor ne

13、rve (III)Trochlear nerve (IV)Trigeminal nerve (V)Abducens nerve (VI)CerebellumMedullaOculomotor Nerve (III)Innervates four of the extrinsic eye musclesTable 14.3 (3 of 12)Filaments ofolfactory nerve (I)Olfactory bulbOlfactory tractOptic nerve (II)Optic chiasmaOptic tractOculomotor nerve (III)Trochle

14、ar nerve (IV)Trigeminal nerve (V)Abducens nerve (VI)CerebellumMedullaTable 14.3 (4 of 12)Trochlear Nerve (IV)Innervates the superior oblique muscle (an extrinsic eye muscle)Filaments ofolfactory nerve (I)Olfactory bulbOlfactory tractOptic nerve (II)Optic chiasmaOptic tractOculomotor nerve (III)Troch

15、lear nerve (IV)Trigeminal nerve (V)Abducens nerve (VI)CerebellumMedullaTrigeminal Nerve (V)Provides sensory innervation to the faceMotor innervation to chewing musclesFilaments ofolfactory nerve (I)Olfactory bulbOlfactory tractOptic nerve (II)Optic chiasmaOptic tractOculomotor nerve (III)Trochlear n

16、erve (IV)Trigeminal nerve (V)Abducens nerve (VI)CerebellumMedullaAbducens Nerve (VI)Abducts the eyeball innervates lateral rectus muscleTable 14.3 (6 of 12)Filaments ofolfactory nerve (I)Olfactory bulbOlfactory tractOptic nerve (II)Optic chiasmaOptic tractOculomotor nerve (III)Trochlear nerve (IV)Tr

17、igeminal nerve (V)Abducens nerve (VI)CerebellumMedullaTable 14.3 (7 of 12)Facial Nerve (VII)Innervates muscles of facial expressionFacial nerve (VII)Vestibulocochlearnerve (VIII)Glossopharyngeal nerve (IX)Vagus nerve (X)Accessory nerve (XI)Hypoglossal nerve (XII)Vestibulocochlear Nerve (VIII)Sensory

18、 nerve of hearing and balanceTable 14.3 (8 of 12)Facial nerve (VII)Vestibulocochlearnerve (VIII)Glossopharyngeal nerve (IX)Vagus nerve (X)Accessory nerve (XI)Hypoglossal nerve (XII)Glossopharyngeal Nerve (IX)Innervates structures of the tongue and pharynxTable 14.3 (9 of 12)Facial nerve (VII)Vestibu

19、locochlearnerve (VIII)Glossopharyngeal nerve (IX)Vagus nerve (X)Accessory nerve (XI)Hypoglossal nerve (XII)Vagus Nerve (X)A mixed sensory and motor nerve - “Wanders” into thorax and abdomenTable 14.3 (10 of 12)Facial nerve (VII)Vestibulocochlearnerve (VIII)Glossopharyngeal nerve (IX)Vagus nerve (X)A

20、ccessory nerve (XI)Hypoglossal nerve (XII)Table 14.3 (11 of 12)Accessory Nerve (XI)An accessory part of the vagus nerve -innervates trapezius muscleFacial nerve (VII)Vestibulocochlearnerve (VIII)Glossopharyngeal nerve (IX)Vagus nerve (X)Accessory nerve (XI)Hypoglossal nerve (XII)Table 14.3 (12 of 12

21、)Hypoglossal Nerve (XII)Runs inferior to the tongue - innervates the tongue musclesFacial nerve (VII)Vestibulocochlearnerve (VIII)Glossopharyngeal nerve (IX)Vagus nerve (X)Accessory nerve (XI)Hypoglossal nerve (XII)Spinal Nerves31 pairs contain thousands of nerve fibersConnect to the spinal cordName

22、d for point of issue from the spinal cord8 pairs of cervical nerves (C1C8)12 pairs of thoracic nerves (T1T12)5 pairs of lumbar nerves (L1L5)5 pairs of sacral nerves (S1S5)1 pair of coccygeal nerves (Co1)Spinal NervesConnect to the spinal cord by the dorsal root and ventral rootDorsal root contains s

23、ensory fibersDorsal root ganglion of afferent cell bodies Ventral root contains motor fibers arising from anterior gray columnBranch into dorsal ramus and ventral ramus both contain sensory and motor fibers Rami communicantes connect to the base of the ventral ramus and lead to the sympathetic chain

24、 ganglia Spinal Nerves(a)Dorsal rootganglionGray matterWhite matterVentral rootDorsal rootDorsal and ventralrootlets of spinal nerveDorsal ramusof spinal nerveVentral ramusof spinal nerveSympathetic trunk(chain) ganglionSpinal nerveRami communicantesInnervation of the BackDorsal rami Innervate back

25、musclesFollow a neat, segmented patternInnervate a horizontal strip of muscle and skinIn line with emergence point from the vertebral columnInnervation of the Thoracic regionVentral rami arranged in simple, segmented patternIntercostal nerves supply intercostal muscles, skin, and abdominal wallEach

26、gives off lateral and anterior cutaneous branches Introduction to Nerve PlexusesNerve plexus a network of nervesVentral rami (except T2 T12)Branch and join with one another Form nerve plexusesCervicalBrachialLumbarSacralPrimarily serve the limbsFibers from ventral rami crisscross The Cervical Plexus

27、Buried deep in the neck under the sternocleidomastoid muscleFormed by ventral rami of first four cervical nerves (C 1 4)Most are cutaneous nervesSome innervate muscles of the anterior neckBrachial PlexusBrachial plexus lies in the neck and axillaFormed by ventral rami of C5 C8 give rise to cordsCords give rise to main nerves of th