Brain Localisation

• Corpus callosum - splits the two hemispheres of the brain

  • nerve fibres that join the two halves and communicate between the left and right side
• Sperry's split brain research

  presented images to each of the visual fields

  sperry found that if participants were asked to point to a matching image, they could perform this regardless of the hemisphere that it was presented to

  but if asked to verbally describe, they could only do this when the image was presented to their left hemisphere

  sperry concluded that language is hemispherically lateralised to the left hemisphere
• limitations of split brain research

  • may lack generalisability
  • brain abnormalities may be a confounding variable
  • not all findings have been replicated
• parts of the brain

  A) Broca's area

  B) Motor cortex

  C) somatosensory cortex

  D) visual cortex

  E) wernicke's area

  
• Petersen et al

  used brain scans to show how wernicke's area was active during a listening task and how broca's area was active during a reading task

  objective methods

  used to show that functions are localised to different parts of the brain
• Case study: Phineas Gage

  case studies can lack generalisability

  pole was pushed into his skull, removing most of his left frontal lobe

  he survived but experienced a complete turn in personality

  suggests that the frontal lobe may be responsible for regulating mood
• a limitation of split brain research comes from danelli

  danelli studied patient EB who had their left hemisphere removed at a young age

  after rehabilitation, EB was able to recover their language skills

  which wouldnt have been possible is language skills were lateralised to the left hemisphere

  danelli conducted the case study through verbal testing and MRI to compare images of their brain with that of people with typical brains

  found that hemispherically lateralised functions can be taken over by the right
• support for the theory of brain localisation

  post-mortem examination of patient Tan

  showed damage to Broca's area

  Dronkers' further examination showed that perhaps there were other brain regions that were also damaged
• brain localisation ignores individual differences in brain organisation