Hemispheric lateralisation and split brain research

• What are the two hemispheres of the brain called?

  Left and right hemispheres
• What happens if the connection between the left and right hemispheres is cut?

  It stops communication between each hemisphere
• What is the name of the connection between the left and right hemispheres?

  Corpus callosum
• How many nerve fibers are in the corpus callosum?

  200 to 300 million nerve fibers
• What is the primary function of the right side of the brain?

  It deals with visual information from the left visual field
• Where are the language centers located in the brain?

  Only in the left side of the brain
• What was the purpose of cutting the corpus callosum in patients?

  To stop electrical seizures from bouncing between the hemispheres
• What condition was treated by cutting the corpus callosum?

  Severe epilepsy
• What did Sperry's research in 1969 focus on?

  Split brain patients
• In Sperry's divided field experiment, how did participants view the stimuli?

  They covered one eye and focused on a dot
• What happens when a split brain patient sees a word in their right visual field?

  They can say the word because it is processed in the left hemisphere
• What can a split brain patient do if they see an object in their left visual field?

  They can draw it with their left hand
• What did Sperry's research reveal about the right hemisphere's capabilities?

  The right hemisphere is better at recognizing faces
• What are some criticisms of Sperry's research using split brain patients?

  • Small sample size limits generalizability
  • Comparison group not representative
  • Variability in disconnection levels among patients
  • Influence of prior drug therapy on results
  • Lack of mundane realism in experimental conditions
• What is alien hand syndrome?

  A condition where one hand acts independently and seems to fight against the other hand
• What are the implications of Sperry's research on our understanding of consciousness?

  • Suggests we are not a unified self
  • Proposes a collection of separate intelligent processes
  • Influences both psychological and philosophical perspectives on the mind