hemispheric lateralisation

Cards (9)

  • what is hemespheric lateralisation?
    • some mental processes are specialised in one hemisphere only e.g. language
    • each hemisphere has its own functional specialisations
    • LEFT: speech and language
    • RIGHT: visual- motor tasks
    • the hemispheres are connected by the corpus callosum (a bundle of nerves)
    • allows interaction and transfer of information
  • hemispheric lateralisation strenghts
    • increases neural processing capacity
    • by only using one hemisphere to engage in a task, the other hemisphere is free to engage in a idfferent function
    • ROGERS found in the little domestic chicken that lateralisation is associated with an enchamced ability to perfrom two tasks at once
  • hemispheric lateralisation strengths
    • RILEA found no sex differences in all categories investigated which demonstrates how the dominant hemispheres arent as dominant as one thought
  • split brain research aim
    • SPERRY AND GAZZANIGA
    • tested the capabilities of the separated hemispheres by sending visual info to just one hemisphere
    • becasue the right hemisphere receives info from the left
  • split brain research procedure
    • SPERRY AND GAZZALINGA
    • 1. patients fixate on a dot in the middle of a screen, their hands are under the table and out of sight
    • 2. imagfe appears in either left or right visual field and asked to respond
    • left hand response (controlled by right hemisphere)
    • verbal response (controlled by left hemisphere)
    • e.g. patient sees a dog in left visual field 'i saw a dog' as left hemisphere controls right visual field and has language centre and sees a cat in the left ' i see nothing'
    • right hemisphere controls left visula field but has no language centre
  • split brain research results
    • SPERRY AND GAZZANIGA
    • left hemisphere is responsible for speech and language
    • right hemisphere is responsible for visual spatial processing and facial recognition
    • connectivity between the hemispheres are as important as localised regional functions
  • split brain research strength
    • scientific - produced large amount of research findings
    • strong, scientific methodology
  • split brain research limitations
    • quantitative data
    • very few people undergo severing their corpus callosum and even less in modern time
    • confounding variable - language isn't restricted to the left hemisphere
  • how was SPERRY and GAZZANIGA'S research limited
    • by the small sample size of split-brain patients
    • there was very few people who had there corpus callosm severed
    • e.g. some patients had been disconnected for longer and the bran would have experienced different degrees of adaption to loss of functions