1. The Nervous System What is it and how does it work?

2. Central Nervous System Peripheral Nervous System

3. The Nervous System Our body’s speedy electrochemical communication network Brain & Spinal Cord form the CENTRAL NERVOUS SYSTEM which communicates with the body’s sensory receptors, muscles, and glands via the PERIPHERAL NERVOUS SYSTEM CNS is in charge of the executive functioning while the PNS serves as the delivery function

4. The Peripheral Nervous System Autonomic Nervous System Controls the body’s automatic actions (breathing, heartbeat, etc) Controls the body’s automatic actions (breathing, heartbeat, etc) controls our glands & muscles of our internal organs, influencing things like glandular activity & digestion controls our glands & muscles of our internal organs, influencing things like glandular activity & digestion may be consciously overridden may be consciously overridden divides into sympathetic & parasympathetic systems Somatic Nervous System Enables voluntary control of our skeletal muscles Enables voluntary control of our skeletal muscles Responsible for processing sensory information that arrives via external stimuli including seeing, hearing, and touching Responsible for processing sensory information that arrives via external stimuli including seeing, hearing, and touching Consists of sensory (afferent) neurons that carry info to CNS & motor (efferent) neurons that carry info from CNS to muscles Consists of sensory (afferent) neurons that carry info to CNS & motor (efferent) neurons that carry info from CNS to muscles

5. The Autonomic Nervous System Sympathetic Nervous System Arouses and expends energy Arouses and expends energy Activated when body is excited, enraged, or challenged Activated when body is excited, enraged, or challenged When stimulated: When stimulated: pupils dilate pupils dilate heartbeat accelerates heartbeat accelerates digestion is inhibited digestion is inhibited stimulates secretion of epinephrine & norepinephrine stimulates secretion of epinephrine & norepinephrine relaxes bladder relaxes bladder stimulates ejaculation in males stimulates ejaculation in males Parasympathetic Nervous System Conserves energy as it calms the body when stress subsides Conserves energy as it calms the body when stress subsides When stimulated: When stimulated: pupils contract pupils contract heartbeat slows heartbeat slows digestion is stimulated digestion is stimulated gallbladder is stimulated gallbladder is stimulated contracts bladder contracts bladder allows blood to flow to sex organs allows blood to flow to sex organs