1. Essentials of Anatomy and Physiology Fifth edition Seeley, Stephens and Tate Slide 2.1 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Chapter 8: Nervous System

2. Spinal Nerves Slide 7.63 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  31 pairs, each arising from a spinal segment  Spinal nerves are all MIXED nerves  Named for the vertebral level from which they arise

3. Spinal Nerves Slide 7.64 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 7.22a

4. Autonomic Nervous System Slide 7.67 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  The involuntary component of the nervous system  Consists of only motor nerves  Divided into two divisions  Sympathetic division  Parasympathetic division

5. Autonomic Nervous System Slide 7.67 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Sympathetic division  “Fight or Flight” response  Specialized to act in emergencies  Short acting  Long term activation leads to “stress disorders”

6. Autonomic Nervous System Slide 7.67 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Parasympathetic division  “Rest and Repose” system  Specialized to return body to homeostasis  Long acting  Where the body is “supposed” to be

7. Differences Between Somatic and Autonomic Nervous Systems Slide 7.68b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Neurotransmitters  Somatic – always use acetylcholine  Autonomic – use acetylcholine, epinephrine, or norepinephrine

8. Anatomy of the Autonomic Nervous System Slide 7.73 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 7.25

9. Autonomic Functioning Slide 7.74a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Sympathetic – “fight-or-flight”  Response to unusual stimuli  Takes over to increase specific activities  The “E” ticket = exercise, excitement, emergency, and embarrassment

10. Autonomic Functioning Slide 7.74b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Parasympathetic – housekeeping activities  Conserves energy  Maintains daily necessary body functions  The “D” division - digestion, defecation, and diuresis (urination)

11. Neurotransmitters Slide 7.74b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Excitatory: facilitate transmission  Acetylcholine  Epinephrine and norepinephrine  Amino acids:  Aspartate: spinal cord  Glutamate: cerebral cortex, brainstem

12. Neurotransmitters Slide 7.74b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Inhibitory: inhibit transmission  GABA  Serotonin (SSRI’s, i.e., prozac, etc.)  Dopamine (cocaine, meth)  Histamine  Endorphins

13. Development Aspects of the Nervous System: FYI Slide 7.75a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  The nervous system forms during the first month of embryonic development  Any maternal infection, chemical use, or radiation exposure can have harmful effects  The hypothalamus is one of the last areas of the brain to develop

14. Development Aspects of the Nervous System: FYI Slide 7.75b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Very few neurons are formed after birth  growth and maturation continue for years  additional pathways are formed  The brain reaches maximum weight as a young adult  As we age, “use it or lose it”!!