Lateralisation

• What is the concept of lateralisation in the brain?

  Lateralisation is the idea that the two halves of the brain are functionally different.
• What does hemispheric lateralisation imply?

  It implies that the two hemispheres of the brain are functionally different.
• Which side of the brain processes information from the left half of the body?

  The right side of the brain processes information from the left half of the body.
• What are some functions associated with the right hemisphere of the brain?

  Facial recognition, drawing ability, and spatial tasks.
• Which side of the brain processes information from the right half of the body?

  The left side of the brain processes information from the right half of the body.
• What function is localized and lateralized in the left hemisphere?

  Language.
• What is a corpus callosotomy?

  It is a surgical procedure where the corpus callosum is severed to separate the two hemispheres of the brain.
• Why are split brain patients studied?

  They are studied to understand how the two hemispheres of the brain function separately.
• What was the aim of Sperry's star study?

  To investigate what functions of the brain are lateralised.
• What were the procedures used in Sperry's study?

  • Compared split brain patients to those without hemisphere separation.
  • Conducted visual tasks by projecting stimuli into left or right visual fields.
  • Conducted tactile tasks with objects hidden from view.
• What happens when a picture is shown to the left visual field of a split brain patient?

  They would not be able to say anything because the right hemisphere does not process language.
• How do split brain patients recognize objects by touch?

  If a picture is shown to the left visual field, they can identify the object with their left hand.
• What occurs when two different objects are placed in each hand of a split brain patient?

  Each hand searches for its own object, and if the left hand picks up the right hand's object, it is rejected.
• What is the outcome when a split brain patient is asked to draw a picture shown to both visual fields?

  The drawings are consistently better when drawn by the left hand, despite being right-handed.
• What happens when a split brain patient sees two different words in each visual field?

  They say the word in the right visual field and pick up the object in the left visual field.
• How do split brain patients respond to face recognition tasks?

  If shown a woman in the left visual field and a man in the right visual field, they say they saw a man but select the photo of the woman.
• What are the conclusions drawn from Sperry's study on split brain patients?

  • Hemispheres process information separately.
  • Hemispheres have differing functions supporting lateralisation.
  • Patients have two separate streams of consciousness with their own memories and perceptions.
• What are the strengths and weaknesses of Sperry's study?

  Strengths:

  • Quasi-experiment in controlled conditions (good internal validity).
  • Pictures flashed briefly to ensure hemisphere-specific processing.

  
  

  Weaknesses:

  • Small sample size (11 patients) limits generalizability.
  • Lack of ecological validity due to artificial conditions.
• How does lateralisation increase neural processing capacity?

  By using only one hemisphere to engage in a particular task.
• What evidence supports the idea that lateralisation enhances brain efficiency?

  In chickens, brain lateralisation was associated with enhanced abilities to find food and stay vigilant for predators.
• What did Szaflarski et al (2006) find regarding language lateralisation over time?

  Language became more lateralised to the left hemisphere with age in children and adolescents, then decreased after age 25.
• What is a disadvantage associated with having a lateralised brain?

  Being left-handed is linked with poorer immunity.
• What did Gazzaniga's case study of patient JW suggest about lateralisation?

  It suggested that language can be recovered by the right hemisphere, supporting brain plasticity.
• Which side of the brain processes information from the left half of the body?

  The RIGHT side of the brain
• What are the key functions associated with the right and left hemispheres of the brain?

  Right hemisphere:

  • Facial recognition and emotions
  • Drawing ability
  • Spatial tasks

  
  

  Left hemisphere:

  • Language processing
• What procedure was done on the "split brain" patients in the Sperry study?

  The corpus callosum was severed, separating the two hemispheres of the brain and preventing them from communicating with each other.
• What was the time duration that the visual stimuli were flashed to the patients in the Sperry study?

  1/10th of a second
• How did the Sperry study demonstrate that the hemispheres of the brain have differing functions?

  The study showed that split brain patients had separate streams of consciousness, memories, and perceptions in each hemisphere, with the left hemisphere responsible for language and the right hemisphere for tasks like facial recognition and drawing.
• If you wanted to observe the surface of a cell in detail, which type of microscope would you use?

  Scanning electron microscope
• What is the main idea behind lateralisation?

  The two halves of the brain are functionally different and certain processes, activities or behaviours are controlled by one hemisphere.
• Which side of the brain is responsible for language functions?

  The LEFT side of the brain
• What was the main aim of the Sperry study on split brain patients?

  To investigate what functions of the brain are lateralised.
• What were the key findings from the Sperry study on split brain patients?

  • Patients could not describe objects shown in their left visual field (right hemisphere doesn't process language)
  • Patients could identify objects by touch with their left hand (right hemisphere controls left hand)
  • Patients drew better with their left hand (right hemisphere is superior at drawing)
  • Patients could not integrate information presented to each visual field (hemispheres process information separately)
• What are some of the strengths and weaknesses of the Sperry study on split brain patients?

  Strengths:

  • Good internal validity due to controlled conditions
  • Flashing stimuli for 1/10th second ensured each hemisphere only saw the image in its visual field

  
  

  Weaknesses:

  • Small sample size of 11 patients, limiting generalizability
  • Participants were not randomly assigned, potential participant variables
  • Findings may not generalize to non-epileptic patients
• What is the formula to calculate the area of a circle?

  $A =$$\pi r^2$