Hemispheric lateralisation - AO3

Question 1

What are two limitations of hemispheric lateralisation

Answer 1

• P: Limitation = issues with generalisation
• E: Control group in Sperry’s study did not have epilepsy (confounding variable)
• E: A very small sample size
• L: Sperry’s research lacks external validity
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• P: Limitation = neural plasticity
• E: Following brain damage, some functions can be taken overby the opposite hemispheres
• E: Turk et al. (2002): case study, JW, developed the language capacity in his right hemisphere - could eventually speak about the information in left or right visual field
• L: So, lateralised functions are flexible rather than fixed

Question 2

What is a strength of hemispheric lateralisation?

Answer 2

• P: Strength = supporting evidence from neurotypical brains
• E: Fink et al (1996): PET scans of people looking at an image
• E: Activity in RH for global parts of a picture LH for finer detail
• L: Visual processing is lateralised and two hemispheres communicate to give full picture

Question 3

What is a third limitation of hemispheric lateralisation?

Answer 3

• P: Limitation = evidence from brain scans
• E: Szaflarski et al (2006): compared fMRIs of children and adults ages 5-67
• E: Evidence that brain becomes more lateralised up to age 25, then less lateralised with each decade
• L: So, people are not “left or right brained” despite some functions being lateralised