Split brain research into hemispheric lateralisation

• hemispheric lateralisation


  • the idea that both sides of the brain are functionally different
  • certain mental process and behaviours are controlled by one hemisphere
• Sperry


  • group of individuals who had had corpus callous cut to separate hemispheres and control epileptic seizures.
  • the main line of communication between the two hemispheres was removed
• Sperry's procedure


  • ppts would sit at a screen, cover one eye and look at a dot.
  • he could then flash images independently to the right and left visual fields.
  • ppts were then asked to draw objects, say what they saw or select objects that were hidden from their view
• what did sperry find about describing what pps could see

  • when it was shown to the right visual field
  • ppts could easily describe what it was
  • but when shown to the left they couldn't
  • this is because the lack of language centres in the left side of the brain
• what did Sperry find about drawing an object

  if object was presented to the right hempishere it could be drawn because the right hemisphere has control of the left hand
• Developed understanding


  Sperrys research has led us to understand that the right side of the brain is better at spatial and musical tasks, whilst the left side is better at analytical and verbal tasks
• Methodolgy


  used standardised procedure and only endured one hemisphere was receiving information, good internal validity BUT low ecological validity, and in the real world, having a split Brian really isn't a problem
• Non generalisable


  people with split brains are unusual and only 11 people took part in the study which is a very small sample size, some people experience more disconnection from hemispheres BUT his control group did not have a history of epilepsy therefore we cannot see this as a comparison