Brain structure

• Brain


  Protected in skull (sku11) and encased in protective membranes called meninges
• Brain


  Made up of billions of interconnecting neurones, that form different regions
• Brain regions


  • Cerebral cortex
  • Cerebellum
  • Medulla
  • Hypothalamus
  • Pituitary gland
• Cerebral cortex


  • Concerned with consciousness, intelligence, memory, language
• Cerebellum


  • Concerned with coordinating muscular activity and balance
• Medulla


  • Concerned with unconsciousness, eg heartbeat, movements of the gut, breathing
• Hypothalamus


  • Controls body temperature
• Pituitary gland


  • Produces different chemicals (hormones) which coordinate and control body systems
• Matching behaviour/memory with damaged area has helped scientists map the functions of some parts of the brain
• Phineas Gage survived for 13 years after an iron rod went through his skull
• After the accident, Phineas Gage became wild, rude and unreliable, though he was previously polite and hardworking
• Modern scans show the accident removed part of Phineas Gage's cerebral cortex
• If someone develops a tumor in the brain or has a stroke, it will affect their behaviour
• MRI


  Magnetic resonance imaging, a scan that shows exactly what area of the brain is affected
• MRI scans enable scientists to link the loss of a certain function, such as speech, with damage to a particular region of the brain
• Scientists can expose the brain by removing the top of the skull and stimulate different areas to see the effect
• There are no sensory nerves in the brain, so surgery can be done on conscious patients
• People can experience hunger, anger, fear and thirst because the relevant area of the brain is stimulated
• The brain


  • It is complex and delicate
  • Many processes involve many different neurons and chemicals released in synapses
  • It is easily damaged or destroyed, making it difficult to investigate brain disorders and treat them
  • Drugs don't always reach the brain through the membranes
  • Surgery is difficult because it's not fully understood what each area of the brain actually does