Peripheral Nervous System

1. Peripheral Nervous System Classification of Nerves

2. Classification of Nerves • Mixed nerves • Both sensory and motor fibers • Sensory nerves • Carry impulses toward the CNS • Motor nerves • Carry impulses away from the CNS CNS = Central Nervous System (brain and spinal chord)

3. Cranial Nerves • 12 pairs of nerves that mostly serve the head and neck • Only the pair of vagus nerves extend to thoracic and abdominal cavities • Most are mixed nerves, but three are sensory only

4. PNS: Cranial Nerves • I Olfactory nerve — sensory for smell • II Optic nerve — sensory for vision • III Oculomotor nerve — motor fibers to eye muscles • IV Trochlear — motor fiber to eye muscles

5. PNS: Cranial Nerves • VTrigeminal nerve — sensory for the face; motor fibers to chewing muscles • VIAbducens nerve — motor fibers to eye muscles • VIIFacial nerve — sensory for taste; motor fibers to the face • VIIIVestibulocochlear nerve — sensory for balance and hearing

6. PNS: Cranial Nerves • IXGlossopharyngeal nerve — sensory for taste; motor fibers to the pharynx • XVagus nerves — sensory and motor fibers for pharynx, larynx, and viscera • XIAccessory nerve — motor fibers to neck and upper back • XIIHypoglossal nerve — motor fibers to tongue

9. Table 7.1 (3 of 4)

11. PNS: Distribution of Cranial Nerves Figure 7.24

12. PNS: Classification of Nerves • Mixed nerves • Both sensory and motor fibers • Sensory (afferent) nerves • Carry impulses toward the CNS • Motor (efferent) nerves • Carry impulses away from the CNS

13. PNS: Cranial Nerves • 12 pairs of nerves that mostly serve the head and neck • Only the pair of vagus nerves extend to thoracic and abdominal cavities • Most are mixed nerves, but three are sensory only

14. PNS: Cranial Nerves • I Olfactory nerve—sensory for smell • II Optic nerve—sensory for vision • III Oculomotor nerve—motor fibers to eye muscles • IV Trochlear—motor fiber to eye muscles

15. PNS: Cranial Nerves • V Trigeminal nerve—sensory for the face; motor fibers to chewing muscles • VI Abducens nerve—motor fibers to eye muscles • VII Facial nerve—sensory for taste; motor fibers to the face • VIII Vestibulocochlear nerve—sensory for balance and hearing

16. PNS: Cranial Nerves • IX Glossopharyngeal nerve—sensory for taste; motor fibers to the pharynx • X Vagus nerves—sensory and motor fibers for pharynx, larynx, and viscera • XI Accessory nerve—motor fibers to neck and upper back • XII Hypoglossal nerve—motor fibers to tongue

17. PNS: The Cranial Nerves Table 7.1 (1 of 4)

18. PNS: The Cranial Nerves Table 7.1 (2 of 4)

19. PNS: The Cranial Nerves Table 7.1 (3 of 4)

20. PNS: The Cranial Nerves Table 7.1 (4 of 4)

21. PNS: Distribution of Cranial Nerves Figure 7.24

22. PNS: Classification of Nerves • Mixed nerves • Both sensory and motor fibers • Sensory (afferent) nerves • Carry impulses toward the CNS • Motor (efferent) nerves • Carry impulses away from the CNS

23. PNS: Classification of Nerves • Mixed nerves • Both sensory and motor fibers • Sensory (afferent) nerves • Carry impulses toward the CNS • Motor (efferent) nerves • Carry impulses away from the CNS

24. PNS: Cranial Nerves • 12 pairs of nerves that mostly serve the head and neck • Only the pair of vagus nerves extend to thoracic and abdominal cavities • Most are mixed nerves, but three are sensory only

25. PNS: Cranial Nerves • I Olfactory nerve—sensory for smell • II Optic nerve—sensory for vision • III Oculomotor nerve—motor fibers to eye muscles • IV Trochlear—motor fiber to eye muscles

26. PNS: Cranial Nerves • V Trigeminal nerve—sensory for the face; motor fibers to chewing muscles • VI Abducens nerve—motor fibers to eye muscles • VII Facial nerve—sensory for taste; motor fibers to the face • VIII Vestibulocochlear nerve—sensory for balance and hearing

27. PNS: Cranial Nerves • IX Glossopharyngeal nerve—sensory for taste; motor fibers to the pharynx • X Vagus nerves—sensory and motor fibers for pharynx, larynx, and viscera • XI Accessory nerve—motor fibers to neck and upper back • XII Hypoglossal nerve—motor fibers to tongue

28. PNS: The Cranial Nerves Table 7.1 (1 of 4)

29. PNS: The Cranial Nerves Table 7.1 (2 of 4)

30. PNS: The Cranial Nerves Table 7.1 (3 of 4)

31. PNS: The Cranial Nerves Table 7.1 (4 of 4)

32. PNS: Distribution of Cranial Nerves Figure 7.24

33. PNS: Cranial Nerves • 12 pairs of nerves that mostly serve the head and neck • Only the pair of vagus nerves extend to thoracic and abdominal cavities • Most are mixed nerves, but three are sensory only

34. PNS: Cranial Nerves • I Olfactory nerve—sensory for smell • II Optic nerve—sensory for vision • III Oculomotor nerve—motor fibers to eye muscles • IV Trochlear—motor fiber to eye muscles

35. PNS: Cranial Nerves • V Trigeminal nerve—sensory for the face; motor fibers to chewing muscles • VI Abducens nerve—motor fibers to eye muscles • VII Facial nerve—sensory for taste; motor fibers to the face • VIII Vestibulocochlear nerve—sensory for balance and hearing

36. PNS: Cranial Nerves • IX Glossopharyngeal nerve—sensory for taste; motor fibers to the pharynx • X Vagus nerves—sensory and motor fibers for pharynx, larynx, and viscera • XI Accessory nerve—motor fibers to neck and upper back • XII Hypoglossal nerve—motor fibers to tongue

37. PNS: The Cranial Nerves Table 7.1 (1 of 4)

38. PNS: The Cranial Nerves Table 7.1 (2 of 4)

39. PNS: The Cranial Nerves Table 7.1 (3 of 4)

40. PNS: The Cranial Nerves Table 7.1 (4 of 4)

41. PNS: Distribution of Cranial Nerves Figure 7.24