1. THE PERIPHERAL AND AUTONOMIC NERVOUS SYSTEM Chapter 9

2. © 2004 Delmar Learning, a Division of Thomson Learning, Inc. PERIPHERAL NERVOUS SYSTEM Includes all of the nerves of the body and ganglia Connects the central nervous system to various body structures Controls the involuntary (automatic) activities of vital internal organs Acts as a reflex center of body

3. © 2004 Delmar Learning, a Division of Thomson Learning, Inc. NERVES Sensory (afferent) nerve - fibers carry impulses from sense organs to the brain or spinal cord Motor (efferent) nerve - fibers carry impulses from brain or spinal cord to muscles or glands Mixed nerve - contains both sensory and motor fibers

4. © 2004 Delmar Learning, a Division of Thomson Learning, Inc. CRANIAL AND SPINAL NERVES The cranial nerves are 12 pairs of nerves that begin in various areas of the brain The spinal nerves originate at the spinal cord and go through openings in the vertebrae All 31 pairs of spinal nerves are mixed nerves

5. © 2004 Delmar Learning, a Division of Thomson Learning, Inc. AUTONOMIC NERVOUS SYSTEM Includes nerves, ganglia, and plexuses that carry impulses to all smooth muscle, secretory glands, and heart muscle Regulates the activities of the visceral organs

6. © 2004 Delmar Learning, a Division of Thomson Learning, Inc. AUTONOMIC NERVOUS SYSTEM There are two divisions: –Sympathetic system - consists of two cords of nerve fibers and ganglia extending from base of brain down through spinal column –Parasympathetic system Vagus nerve - chest and neck Pelvic nerve - hip region

7. © 2004 Delmar Learning, a Division of Thomson Learning, Inc. DISORDERS OF THE PERIPHERAL NERVOUS SYSTEM Neuritis Sciatica Neuralgia Trigeminal neuralgia Bell’s palsy Shingles (herpes zoster) Carpal tunnel syndrome