The Central Nervous System

1. The Central Nervous System

2. The Nervous System • The Central Nervous System consists of the brain and the spinal cord • Nerves branching off the brain and spinal cord make up the Peripheral Nervous System • These two work together to tell the brain what is happening inside and outside the body • Makes sure the body responds appropriately to the messages sent • The taking in and reporting of information is called homeostasis

3. The Nervous System • Made of special cells called neurons • Each neuron contains dendrites and axons • Dendrites– carry nerve impulse to the neuron • Axons – carry impulses (information) away from the neuron

4. How it works… • An impulse reaches the top of an axon and jumps to another via an electrical impulse at the synapse (structure that permits a neuron to pass a signal to another cell). • The axon then releases a chemical that allows the impulse to cross the synapse to the next neuron. • This is how messages travel through the nervous system

5. Time to Brainstorm!! Can you think of an example in which a message is instantly received by the brain and the body appropriately reacts to the stimulus? Discuss with your group.

6. The Brain • The main information center of the body • Messages travel to the brain through the synapses of the neurons in the central nervous system • The brain interprets this information and allows the body to act upon it

7. Three parts of the brain • The Cerebrum • The Cerebellum • The Brain Stem (Medulla)

8. The Cerebrum • Largest area of the brain • Makes up 85% of brain’s weight • Found at the front of the brain • Divided into a right (music, colors, and shapes) and left (math, logic, and speech) half (hemisphere) • Functions include learning, interpreting information, logical reasoning, abstract thought, speech and language, vision, interpreting the senses, and memory (short term and long term)

9. The Cerebellum • Second largest area of the brain • Controls voluntary muscle movement • Controls balance, movement, and coordination

10. The Brain Stem (Medulla) • Found between the spinal cord and cerebellum • Connects the rest of the brain to the spinal cord • Sorts through the millions of messages that the brain and the rest of the body send back and forth • Controls all your body’s involuntary actions • Controls breathing, heartbeat, digesting food, circulating blood, and salivating for example

11. Be Good To Your Brain • Eat healthy foods. They contain potassium and calcium, two minerals that are important for the nervous system. • Get a lot of playtime (exercise). • Wear a helmet when you ride your bike or play other sports that require head protection. • Don't drink alcohol, take drugs, or use tobacco. • Use your brain by doing challenging activities, such as puzzles, reading, playing music, making art, or anything else that gives your brain a workout!