Brain Lateralisation

Question 1

What is hemispheric lateralisation?

Answer 1

Idea that two halves of the brain are functionally different, controlling different mental processes

Question 2

Right visual field (RVF)

Answer 2

Projects on the nasal retina on the right eye and temporal retina on the left eye. Processed by the left hemisphere which processes language

Question 3

Left visual field (LVF)

Answer 3

Projects on the nasal retina on the left eye and temporal retina on the right eye. Processed by the right hemisphere which processes visual information

Question 4

Sperry (1968)

Answer 4

Split-brain research on patients who had their corpus callosum removed due to severe epilepsy. When information was presented to the RVF patient could describe what they saw and when presented to the LVF could not describe what they saw but could draw it. This was because information arriving at the cortex could not be exchanged between hemispheres

Question 5

Strength of lateralisation

Answer 5

• Research support (eg. Luck showed split-brain p’s are faster than controls at identifying odd one out in array of similar objects)

Question 6

Limitations of lateralisation

Answer 6

• Methodological issues (eg. Experimental group all had surgery to relieve severe epilepsy but control group had no history of epilepsy and small sample size of 11)
• Contradictory case study evidence (eg. Patient JW developed ability to speak using the right hemisphere)
• Diminishes with age (eg. Szaflarski found beyond 25 the degree of lateralisation decreases, indicating lateralisation is flexible and dynamic)