1.2 - Overview of the Nervous System

The Nervous System

• Central Nervous System (CNS):

• Brain: The control center, responsible for thoughts, emotions, and actions.

• Spinal Cord: The information highway, transmitting messages between the brain and the rest of the body.

• Peripheral Nervous System (PNS): The nerves that branch out from the CNS to the rest of the body. Basically, connects the CNS to the rest of the body.

Two Branches of the Peripheral Nervous System:

• Autonomic Nervous System (ANS): Regulates involuntary bodily functions. Has two branches:

  • Sympathetic Nervous System: Activates the "fight-or-flight" response in stressful situations, increasing heart rate, breathing, and releasing adrenaline.

  • Parasympathetic Nervous System: Calms the body down after stress, promoting rest and digestion (homeostasis).

• Somatic Nervous System: Controls voluntary muscle movement and carries messages from the sense organs.