MAJOR REGION OF THE BRAIN

• Cerebral hemispheres


  The two halves of the cerebrum
• Cortex


  • Localizes and interprets sensory inputs
  • Controls voluntary and skilled skeletal muscle activity
  • Acts in intellectual and emotional processing
• Basal nuclei


  • Subcortical motor centers help control skeletal muscle movements
• Thalamus


  • Relays sensory impulses to cerebral cortex
  • Relays impulses between cerebral motor cortex and lower motor centers
  • Involved in memory
• Hypothalamus


  • Chief integration center of autonomic (involuntary) nervous system
  • Regulates body temperature, food intake, water balance, and thirst
  • Regulates hormonal output of anterior pituitary gland and acts as an endocrine organ (producing ADH and oxytocin)
• Limbic system


  • Includes cerebral and diencephalon structures
  • Mediates emotional response; involved in memory processing
• Midbrain


  • Contains visual and auditory reflex centers
  • Contains subcortical motor centers
  • Contains nuclei for cranial nerves III and IV; contains projection fibers (e.g., fibers of the pyramidal tracts)
• Pons


  • Relays information from the cerebrum to the cerebellum
  • Cooperates with the medullary centers to control respiratory rate and depth
  • Contains nuclei of cranial nerves V-VII; contains projection fibers
• Medulla oblongata


  • Relays ascending sensory pathway impulses from skin and proprioceptors
  • Contains nuclei controlling heart rate, blood vessel diameter, respiratory rate, vomiting, etc.
  • Relays sensory information to the cerebellum
  • Contains nuclei of cranial nerves VIII-XII; contains projection fibers
  • Site of crossover of pyramids
• Reticular formation


  • Maintains cerebral cortical alertness; filters out repetitive stimuli
  • Helps regulate skeletal and visceral muscle activity
• Cerebellum


  • Processes information from cerebral motor cortex, proprioceptors, and visual and equilibrium pathways
  • Provides "instructions" to cerebral motor cortex and subcortical motor centers, resulting in smooth, coordinated skeletal muscle movements
  • Responsible for proper balance and posture