localisation of the brain

• Localisation of Function


  The idea that certain functions (e.g. language, memory, etc.) have certain locations within the brain
• Broca's Area


  • Named after Paul Broca
  • Patient Tan - Could only say 'Tan'
  • Post-mortem examination, lesion on left frontal lobe (Broca's area)
  • Responsible for speech production
• Wernicke's Area


  • Named after Carl Wernicke
  • Patients who could talk but not understand language
  • Lesion to left temporal lobe
  • Responsible for language comprehension
• Brain Regions


  • Motor Area
  • Somatosensory Area
  • Visual Area
  • Auditory Area
  • Broca's Area
  • Wernicke's Area

  
• Motor Area


  Located in the frontal lobe and is responsible for voluntary movements by sending signals to the muscles in the body
• Somatosensory Area


  Located in the parietal lobe and receives incoming sensory information from the skin to produce sensations related to pressure, pain, temperature, etc.
• Visual Area


  Located at the back of the brain, in the occipital lobe, and receives and processes visual information

  
• Auditory Area


  Located in the temporal lobe and is responsible for analysing and processing acoustic information
• Information from the right-hand side visual field is processed in the left hemisphere, and information from the left-hand side visual field is processed in the right hemisphere
• Information from the left ear goes primarily to the right hemisphere and information from the right ear goes primarily to the left hemisphere
• The motor area on one side of the brain controls the muscles on the opposite side
• The somatosensory area on one side of the brain receives sensory information from the opposite side of the body

  
• Localisation of function is the idea that certain functions (e.g. language, memory, etc.) have certain locations within the brain
• The Broca's area in the left frontal lobe is responsible for speech production
• The Wernicke's area in the left temporal lobe is responsible for speech comprehension
• Lashley proposed the equipotentiality theory, which suggests that the basic motor and sensory functions are localised, but that higher mental functions are not
• Lashley claimed that intact areas of the cortex could take over responsibility for specific cognitive functions following brain injury
• Broca's aphasia is an impaired ability to produce language; in most cases, this is caused by brain damage in Broca's area
• Wernicke's aphasia is an impairment of language perception, demonstrating the important role played by this brain region in the comprehension of language
• Herasty (1997) found that women have proportionally larger Broca's and Wernicke's areas than men, which can perhaps explain the greater ease of language use amongst women