pns  structure of nerves  cranial nerves  spinal nerves  sensory receptors  motor...

Download PNS  Structure of Nerves  Cranial Nerves  Spinal Nerves  Sensory receptors  Motor control

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  • PNS Structure of Nerves Cranial Nerves Spinal Nerves Sensory receptors Motor control

  • Structure & Classification of Nerves

    Classification:Sensory, Motor, Mixed, Cranial & Spinal nerves; Ganglia

  • Cranial Nerves12 pair of nerves arise from brain exit through foramina leading to muscles, glands and sense organs in head & neck

    Input & output ipsilateral except CN II and IV

  • I: Olfactory NerveII: Optic Nerve

  • III: Oculomotor Nerve & IV: Trochlear Nerve

  • V: Trigeminal NerveVI: Abducens Nerve

  • VII: Facial NerveVIII: Vestibulocochlear Nerve

  • IX: Glossopharyngeal NerveX: Vagus Nerve

  • XI: Accessory NerveXII: Hypoglossal Nerve

  • Cranial Nerve DisordersTrigeminal neuralgia (tic douloureux)recurring episodes of intense stabbing pain in trigeminal nerve areapain triggered by touch, drinking, washing facetreatment may require cutting nerve

    Bells palsydisorder of facial nerve causes paralysis of facial muscles on one sidemay appear abruptly w/ full recovery w/in 3-5 weeks

  • Spinal Nerves- 31 pairs of mixed nerves

    - connect to cord via dorsal & ventral roots and rootlets

    - away from cord branch into dorsal & ventral rami

    - nerve plexuses

    - nerve damage

  • Dermatomes: skin segment innervated by cutaneous sensory spinal nerve

  • Sensory ReceptorsStimulus type:mechanoreceptor, thermoreceptors, nociceptors, chemoreceptors & photoreceptors

    Source:exteroceptors, interoceptors & proprioceptors

    Structural complexity:simple vs. complex

  • Organization of Somatosensory System1. Receptor level: sensory receptors

    2. Circuit level: ascending fiber tracts

    3. Perceptual level: cerebral cortex

  • Hierarchy of Motor Control