Hemispheric Lateralisation

Question 1

What is Hemispheric Lateralisation?

Answer 1

The idea that the two hemispheres of the brain are functionally different, and that specific behaviours and mental processes are controlled predominately by one hemisphere

Question 2

What is an example of Hemispheric Lateralisation?

Answer 2

Language, as both Broca (language production) and Wernicke’s (language understanding) areas are typically in the left hemisphere of the brain

Question 3

Are all areas of the brain lateralised?

Answer 3

No- many aren’t

Question 4

Describe Sperry’s Split-Brain Research

Answer 4

• Studied 11 people who had split-brain surgery, meaning the left and right hemispheres of their brain had been surgically severed
• He used a setup to momentarily project one image to the participants right visual field and a separate image to their left visual field

Question 5

Why was Split-Brain Surgery performed?

Answer 5

To reduce symptoms in individuals with epilepsy

Question 6

Describe Sperry’s Split-Brain Research Findings (2 Findings)

Answer 6

• Individuals could only describe the image projected to their RVF, as the RVF is connected to the left hemisphere of the brain, where the language centres are
• When asked to describe the image projected to their LVF, participants said there was nothing there
• However, participants could draw and select the images projected to LVF despite not being able to articulate what they had seen, as mind-muscle connection was not severed

Question 7

What is it called when one side of the brain controls functioning on the opposite side?

Answer 7

Contralateral control

Question 8

Describe the train of contralateral control between the right and left hemispheres of the brain

Answer 8

• Left Visual Field - Right Hemisphere - Left Hand
• Right Visual Field - Left Hemisphere - Right Hand

Question 9

What function appears to lateralised to the right hemisphere of the brain?

Answer 9

Facial recognition

Question 10

Why has Sperry’s Split-Brain Research been praised?

Answer 10

It is scientific, objective and can be replicated, ensuring its internal validity

Question 11

Why has Sperry’s Split-Brain Research been criticised? (2 Points)

Answer 11

• He used a small sample consisting solely of individuals with epilepsy, meaning his findings may not be generalisable
• He may have overstated the impact that hemispheric lateralisation has by using an artificial setup that isolates the two visual fields, which isn’t reflective of everyday scenarios

Question 12

Who found similar findings to Sperry?

Answer 12

Gazzaniga et al

Question 13

What connects the two hemispheres of the brain, allowing them to communicate?

Answer 13

The corpus collosum

Question 14

What debate is there regarding Hemispheric Lateralisation?

Answer 14

• Some psychologists argue that the two hemispheres of the brain are very functionally different, and that we are all in ’two minds’
• However, other argues that the two hemispheres are far more integrated, and collaborate, communicate and work together when performing everyday tasks
• There is not one overruling, widely agreed stance or paradigm in terms of hemispheric lateralisation within the field of psychological research