Hemispheric lateralisation, lang centres & split brain study

• What is the theory of hemispheric lateralisation?

  It is the theory that each half of the brain is functionally different.
• Which hemisphere of the brain is dominant for language according to hemispheric lateralisation?

  The left hemisphere is dominant for language.
• What connects the two hemispheres of the brain?

  The corpus callosum connects the two hemispheres.
• What is the purpose of the corpus callosum?

  It allows the left and right hemispheres to communicate with one another.
• Who conducted the 'split-brain' lab experiments?

  Sperry and Gazzaniga conducted the 'split-brain' lab experiments.
• What was the purpose of the split-brain procedure?

  It was used as a treatment for severe epilepsy.
• In visual tests, what was shown to the participants?

  A picture was shown to either the left or right visual field.
• What were the results when a picture was shown in the right visual field?

  Participants could name it when shown in the right visual field.
• Why could participants not name what was shown in the left visual field?

  Because the left hemisphere is specialised in language processing.
• What could patients do with their left hand when shown something in the left visual field?

  They could draw what they had seen with their left hand.
• In tactile tests, what was the task given to the patients?

  They had to describe what they felt when an object was placed in their hand.
• What was the result when objects were held in the right hand?

  Objects held in the right hand could be named.
• What was the result when objects were held in the left hand?

  Objects held in the left hand could not be named.
• What does the evidence from tactile tests suggest about the left hemisphere?

  It suggests that the left hemisphere is specialised for language.
• What is a strength of the theory of lateralisation of function?

  The supportive evidence tends to be lab based and replicable.
• How did Sperry and Gazzaniga ensure that information was isolated to one hemisphere during their research?

  Participants stared at a central point while the image was flashed for a tenth of a second.
• Why is the small sample size a limitation of the theory of lateralisation of function?

  Because it is difficult to generalise the results to the wider population.
• What is a challenge in generalising findings from split-brain research?

  Findings are often based on small samples of split-brain patients.
• What does the rarity of split-brain patients imply for research conclusions?

  It implies that conclusions about lateralisation may not apply to everyone.