1. The Structure of the Nervous System

2. Divisions of the Nervous System

3. The Nervous System: Central Nervous System CNS Peripheral Nervous Systems PNS

4. Central Nervous System (CNS): - brain - spinal cord

5. Peripheral Nervous System (PNS) The nerves that connect the CNS to the rest of the body The system is subdivided into the somatic and autonomic nervous systems.

6. Autonomic Nervous System Monitors the autonomic functions (breathing, blood pressure, digestion) Divided into the sympathetic and parasympathetic nervous systems

7. Sympathetic Nervous System: In charge of arousal responses such as “fight or flight” (helps us deal with perceived threats)

8. Parasympathetic Nervous System: Calms the body and brings it back to a relaxed state

9. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

10. HOW DOES THE NERVOUS SYSTEM WORK?

11. I. Neuron - The basic building block of the nervous system (a nerve cell) Receive, Carry, and Pass information on to the next neuron

12. Parts of the Neuron

13. Dendrites Receive information into the cell body.

14. Soma - cell body of a neuron Nucleus: the organelle that is located in the center of the cell body of a neuron.

15. Axon - takes information away from the cell body.

16. Myelin Sheath: Fatty material that surrounds some axons its purpose is to protect the axon and speed processing.

17. Axon Terminal: the end of the neuron, it releases neurotransmitters into the synaptic cleft

18. Neurons

19. Neuron

20. Neural Communication: The Neural Impulse

21. 1. Action Potential A brief electrical charge that travels down the axon of the neuron.

22. 2. Neurotransmitters: Chemical messengers that are released into the synapse. a.Examples: Acetylcholine (movement), Serotonin (mood) b. Are also found in psychiatric medications and other substances

23. Antagonists: block neurotransmitters if you have too much (ex: People with Schizophrenia have 6x the proper level of dopamine!) Agonists: mimic neurotransmitters when you don’t have enough (ex: Depression is caused by low levels of serotonin.)

24. 3. Synapse: A space or “junction” between two neurons The gap where neurotransmitters are released by one neuron and absorbed by the next neuron

25. Neurotransmitters

26. How Do Neurons Communicate? First, neurotransmitters are received by the dendrites. Then, the information is processed by the soma. Next, an action potential occurs, sending information down the axon. Finally, neurotransmitters are released at the axon terminal for the next neuron to absorb.

30. C. Types of Neurons Sensory - carry information to the central nervous system from the sensory organs (eye, ear, skin, etc.) Motor - carry information from the central nervous system to the muscles and glands

31. A Neural Chain