FUNCTIONS OF THE NERVOUS SYSTEM

• Functions of the Nervous System:

  • Maintains homeostasis
  • Sensory input - gathering information
  • Integration - interprets input and decides action
  • Motor output - response
  • Establishes and maintains mental activity
• Divisions of the Nervous System:

  • Central Nervous System (CNS)
  • Peripheral Nervous System (PNS)
• Central Nervous System (CNS) - Involves the brain and spinal cord; command center; responsible for interpreting sensory information
• Peripheral Nervous System (PNS) - involves the cranial and spinal nerves extending from the brain and spinal cord, which carry impulses from the brain and spinal cord, respectively, to the rest of the body
• 2 Divisions of the PNS:

  • Sensory (afferent) division
  • Motor (efferent) division
• Sensory (afferent) division - carry information to the central nervous system
• Fibers in the Sensory Division:

  • Somatic sensory fibers - from skin, skeletal muscles, and joints
  • Visceral sensory fibers - from visceral organs
• Motor (efferent) division - carry impulses to the effector organs
• Subdivisions of the Motor (efferent) division:

  • Somatic nervous system - voluntary (skeletal muscles)
  • Autonomic nervous system - involuntary (smooth and cardiac muscles, glands)
• Divisions of the autonomic nervous system:

  • Sympathetic nervous system - "fight-or-flight"
  • Parasympathetic nervous system - "rest-and-digest"