lateralisation of function

• What does lateralisation of function refer to?

  Different functions of left and right hemispheres
• What early research demonstrated lateralisation of language function?

  Broca's study of Tan
• What did Broca's study of Tan reveal about lateralisation?

  The left hemisphere is responsible for language production
• What did Wernicke find regarding the left hemisphere?

  It is responsible for comprehension of language
• What technique was pioneered in the 1950s to treat epilepsy?

  Severing the corpus callosum
• What is the corpus callosum?

  Bundle of nerve fibres connecting hemispheres
• How did severing the corpus callosum affect epilepsy?

  It reduced the 'electrical storms' leading to seizures
• What opportunities did split brain research provide psychologists?

  • Investigate functions of each hemisphere in isolation
  • Provide evidence for lateralisation
  • Discover processing capabilities of each hemisphere
• Who are the two most renowned researchers in split brain research?

  Sperry and Gazzaniga
• What happens in a typical split brain study?

  Participants focus on a center screen while images flash
• What occurs when a picture is flashed to the right visual field?

  Participants can name the picture
• What occurs when a picture is flashed to the left visual field?

  Participants state they have seen nothing
• Why do participants report seeing nothing when a picture is shown to the left visual field?

  The left hemisphere has not seen the picture
• What can participants do with their left hand when a picture is shown to the left visual field?

  Draw what they have seen
• What happens when an object is placed in the right hand of a split brain patient?

  Participants can name the object
• What happens when an object is placed in the left hand of a split brain patient?

  Participants report holding nothing verbally
• What can participants do with their left hand when an object is placed in the left hand?

  Pick the correct object from an array
• What has split brain research confirmed about language processing?

  Language is primarily processed in the left hemisphere
• What limited capacity was demonstrated by the right hemisphere in split brain research?

  Limited capacity for language comprehension
• What could the right hemisphere instruct the left hand to do?

  Pick a ball from an array of objects
• What was found about the right hemisphere's abilities in split brain research?

  Superior at facial recognition and shape matching
• What are the key issues with split brain research?

  • Small sample sizes
  • Participants had severe epilepsy
  • Results may not generalize to the population
• How have Sperry's methods been modified for neurotypical participants?

  Using the divided field technique
• What does the divided field technique involve?

  • Two stimuli presented simultaneously
  • One to the right visual field
  • One to the left visual field
  • Participant reports what they saw immediately
• What did Levine & Koch-Weser find regarding stimuli presentation?

  Words are reported from the right visual field
• What did Levine & Koch-Weser find about face recognition?

  Faces are reported from the left visual field
• What do the findings of Levine & Koch-Weser support?

  • Left hemisphere superior at processing language
  • Right hemisphere superior at facial recognition
  • Evidence for lateralisation of function
• What is the main question regarding hemispheric lateralisation?

  Are the two hemispheres specialised for different functions?
• What does the case of EB show about lateralisation?

  It provides insights into hemispheric functions
• What conclusions can be drawn about lateralisation of function?

  • Lateralisation affects language and cognition
  • Damage to one hemisphere impacts specific functions
  • Research supports the concept of lateralisation
• What are the objectives for evaluating lateralisation?

  • Define lateralisation
  • Describe functions of each hemisphere
  • Evaluate split brain research
  • Discuss implications of lateralisation
• How can unusual behavior in split brain patients be tested?

  Using split visual field or dichotic listening
• What are some plausible stimuli for testing split brain patients?

  Visual, faces, words, auditory, digits
• What is a plausible task for split brain patients?

  Verbal or visuospatial response tasks
• What are some evaluation points for research using split brain patients?

  • Disconnection varies among patients
  • Drug therapy duration varies
  • Comparison groups often invalid
  • Data may not reflect real-life scenarios
• What does Robert's case illustrate about hemispheric lateralisation?

  Language centres are lateralised to the left hemisphere
• What does damage to Wernicke's area lead to?

  Receptive or sensory aphasia
• What does damage to Broca's area lead to?

  Production or expressive aphasia
• What does right-sided paralysis indicate in cases like Robert's?

  Lateralised damage to the left hemisphere
• Why can Robert understand speech but not produce it?

  Broca's area is damaged, affecting production