Hemispheric Lateralisation

• Hemispheric lateralisation is the theory that functions are controlled by one side of the brain
• Which side of the brain controls the right side of the body?

  Left hemisphere
• What does the right hemisphere control?

  Left side of the body and visual-motor skills
• What is meant by contralateral organization?

  Different hemispheres control the opposite sides of the body
• What is aphasia?

  Someone who is no longer able to understand or comprehend speech
• Which hemisphere are Broca's and Wernicke's areas lateralized to?

  Left hemisphere
• Who conducted split-brain research?

  Sperry and Gazzaniga
• What was the purpose of Sperry's 1968 research?

  To study the effects of cutting the corpus callosum on brain function
• What happens when an image is flashed to the left visual field of a split-brain patient?

  The right hemisphere cannot communicate what it saw
• What was the first task participants had to perform in Sperry's study?

  Describe what they saw from either the left or right visual field
• What was the outcome when a picture was presented to the right visual field?

  The participant could communicate what they saw
• What was the outcome when a picture was presented to the left visual field?

  The participant was unable to communicate what they saw
• In the tactile test, what could participants do with their right hand?

  Describe the object they felt
• What was the outcome for the left hand in the tactile test?

  The participant could not describe the object
• What task involved drawing in Sperry's study?

  Participants had to draw what they saw from either visual field
• What was a notable finding regarding the left visual field in the drawing task?

  Participants could draw what they saw but not communicate
• What was a notable finding regarding the right visual field in the drawing task?

  Participants could not draw what they saw
• What are the strengths and weaknesses of Sperry's split-brain research?

  Strengths:

  • Highly scientific controlled lab experiment
  • Standardized procedure

  
  

  Weaknesses:

  • Small sample size limits generalizability
  • Variability in the extent of corpus callosum cut
  • Contradictory findings regarding brain plasticity