2. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Classification of cranial nerves Sensory cranial nerves: contain only afferent (sensory) fibers Ⅰ Olfactory nerve Ⅱ Optic nerve Ⅷ Vestibulocochlear nerve Motor cranial nerves: contain only efferent (motor) fibers Ⅲ Oculomotor nerve Ⅳ Trochlear nerve Ⅵ Abducent nerve Ⅺ Accessory nerv Ⅻ Hypoglossal nerve Mixed nerves: contain both sensory and motor fibers--- Ⅴ Trigeminal nerve, Ⅶ Facial nerve, Ⅸ Glossopharyngeal nerve Ⅹ Vagus nerve

3. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Sensory cranial nerves N.Location of cell body and axon categories Cranial exitTerminal nucleiMain action Ⅰ Olfactory cells (SVA)Cribrifom foramina Olfactory bulbSmell Ⅱ Ganglion cells (SSA)Optic canalLateral geniculate body Vision Ⅷ Vestibular ganglion(SSA) Internal acoustic meatus Vestibular nuclei Equilibriu m Cochlear ganglion (SSA) Cochlear nucleiHearing

4. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Motor cranial nerves N.Nucleus of origin and axon categories Cranial exitMain action Ⅲ Nucleus of oculomotor (GSE) Superior orbital fissure Motot to superior, inferior and medial recti; inferior obliquus; levator palpebrae superioris Accessory nucleus of oculomotor (GVE) Parasympathetic to sphincter pupillea and ciliary muscl Ⅳ Nucleus of trochlear nerve (GSE) Superior orbital fissure Motor to superior obliquus Ⅵ Nucleus of abducent nerve (GSE) Superior orbital fissure Motor to lateral rectus Ⅺ Nucleus of accessory nerve (SVE) Jugular foramenMotor to sternocleidomastoid and trapezius Ⅻ Nucleus of hypoglossal nerve( GSE) Hypoglossal canalMotot to muscles of tongue

5. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Olfactory nerve Olfactory mucosa (SVA)→ Cribriform foramina → Olfactory bulb

6. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Optic nerve Ganglion cell (SSA) → Optic canal → Lateral geniculate body

7. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Vestibulocochlear nerve Vestibular ganglion(SSA) ↘ ↗ Vestibular nuclei Internal acoustic meatus Cochlear ganglion (SSA) ↗ ↘ Cochlear nuclei

8. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Oculomotor nerve

9. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Abducent nerve Accessory nerve

10. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Hypoglossal nerve

11. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Oculamotor paralysis Abducent nerve injury

12. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Mixed cranial nerves

13. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Trigeminal nerve

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15. Branches Ophthalmic nerve

16. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Distribution:

17. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Maxillary nerve

18. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Distribution :

19. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Mandibular nerve ( Ⅴ 3, mixed)

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21. Distribution :

22. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Facial nerve ( Ⅶ )

23. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Branches within the facial canal

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27. Injury to the facial nerve

28. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Glossopharyngeal nerve ( Ⅸ )

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30. Vagus nerve ( Ⅹ )

31. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Points to Remember Cranial nerves are part of the peripheral nervous system. Carry sensory or motor information or a combination and function in parasympathetic nervous system. Cranial nerves I, II and VIII are purely sensory. Cranial nerves III, IV, VI, XI and XII are motor (although also function for proprioception).

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33. Autonomic Nervous System Sympathetic Parasympathetic

34. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Sympathetic Nervous System Also called thoracolumbar system (T1-L2) Preganglionic cell bodies in lateral horn Preganglionic fibers leave spinal cord with ventral roots Leave spinal nerve via white rami communicans Postganglionic cell bodies in ganglia Sympathetic chain (paravertebral) Collateral (prevertebral)

35. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Sympathetics - Functions Prepares body for fight or flight Increases: heart rate, blood pressure, blood flow to skeletal muscles, respiration Decreases: Peristalsis, blood supply to viscera, glandular secretion Dilates pupils (Note: no sympathetics in accommodation) Stimulates sweat glands Stimulus generalized, long-lasting

36. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Parasympathetic Nervous System Craniosacral outflow Cranial nerves III, VII, IX, X Sacral spinal nerves 2, 3, 4 Preganglionic cell bodies in cranial nuclei, sacral spinal cord Ganglia Special ganglia in head: ciliary, pterygopalatine, submandibular, otic Intrinsic ganglia on or in organ innervated Preganglionic fibers long; postganglionic fibers short

37. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Parasympathetics - Functions Preserve the body as a vegetative organ Decreases heart rate Increases peristalsis Constricts pupil Accommodates eye Empties bladder, rectum Stimulates salivary, lacrimal, digestive glands Stimulus discrete, localized, short-lived Note: no parasympathetics to blood vessels, sweat glands

38. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings