Central Nervous System Overview

Central Nervous System

• The central nervous system, including the brain and spinal cord, is contained within the bony structures of the skull and vertebral column.

Brain Function

• Specific brain regions receive sensations from various body areas.
• Commands to muscles originate in other brain areas.

Spinal Cord

• The spinal cord contains most neurons that enter and leave the brain.
• It links the brain to the rest of the body.

Peripheral Nervous System

• The peripheral nervous system consists of nerves and associated cells outside the brain and spinal cord.
• It has two major divisions: sensory and motor.

Sensory Division

• The sensory division consists of receptor cells that gather information and sensory neurons that transmit impulses from sense organs to the central nervous system.

Motor Division

• The motor division transmits impulses from the central nervous system to muscles and glands.
• Messages are relayed through the somatic nervous system and autonomic nervous system.

Somatic Nervous System

• The somatic nervous system regulates activities such as skeletal muscle movement.
• Some actions are under voluntary control, such as lifting a finger or wiggling toes.
• Other actions occur automatically, like recoiling from pain when stepping on a tack.