Topic 1.2 - Overview of the Nervous System.pptx

Overview of the Nervous system for AP Psychology

1. Unit 1 Biological Bases of Behavior

2. Topic 1.2 – Overview of the Nervous System Learning Target: Differentiate among the subsystems of the human nervous system and their functions. Vocab: Spinal Cord Peripheral Nervous System Autonomic Nervous System Somatic Nervous System Parasympathetic Nervous System Sympathetic Nervous System

3. Central Nervous System The central nervous system includes the brain and the spinal cord and interacts with all processes in the body. The CNS is the body’s decision maker. Our brains are made up of billions of neurons that work together in neural networks. Learning occurs as experience strengthens connections between neurons. The spinal cord is the two-way highway. It sends up (to the brain) sensory information and it sends back motor-control information.

4. The information highway – with reflexes Information travels to and from the brain by way of the spinal cord made up of neural fibers. Were the top of your spinal cord severed, you would not feel pain from your paralyzed body below. Nor would you feel pleasure. With your brain literally out of touch with your body, you would lose all sensation and voluntary movement in body regions with sensory and motor connections to the spinal cord below its point of injury. You would exhibit knee-jerk reflex without feeling the tap.

5. Peripheral nervous system The peripheral nervous system relays messages from the central nervous system to the rest of the body and includes the autonomic and somatic nervous systems. The autonomic nervous system governs processes that are involuntary and includes the parasympathetic and sympathetic nervous systems. The somatic nervous system governs processes that are voluntary.

6. Somatic nervous system The Somatic nervous system enables voluntary control of our skeletal muscles. When a friend taps you on the shoulder, your Somatic Nervous System reports to your brain the current state of your skeletal muscles and carries instructions back, triggering your head to turn.

7. Autonomic Nervous System The ANS controls our glands and our internal organ muscles. The ANS influences functions such as glandular activity, heartbeat, and digestion. (hence “auto”). It is possible to override this system, but it usually operates on its own. There are two subdivisions of the autonomic nervous system: Sympathetic Nervous System Parasympathetic Nervous System

8. Sympathetic Nervous System “Fight or flight” It arouses and expends energy. Accelerates your heartbeat, raises your blood pressure, slows your digestion, raises your blood sugar, cools you with sweat, making you alert and ready for action. Response to stress, bears, phobias, and many other triggers.

9. Parasympathetic Nervous system “rest and digest” When the stress subsides, you body (the PNS) will produce the opposite effects – conserving energy as it calms you. These systems work together to keep our bodies in a steady internal state called homeostasis.