Hemispheric Lateralisation

Question 1

What is Hemispheric Lateralization

Answer 1

Each hemisphere of brain (left/right) is specialised to perform different functions

Question 2

How is the brain contralateral

Answer 2

Each hemisphere of brain controls the opposite side of the body, including both motor and sensory pathways s d vision of the contralateral visual field

Question 3

What connects the two hemispheres

Answer 3

Corpus callosum - bundle of 200-300 million nerve fibres (white matter) connecting hemispheres

Question 4

Sperry (1968) split brain studies procedure

Answer 4

• 11 patients with severed corpus callosum to treat epilepsy
• say objects seen, or draw/select object hidden from view with hand

Question 5

Sperry (1968) findings

Answer 5

Information presented to left hemisphere could be spoken, right hemisphere could only draw or select object using left hand

Question 6

Sperry (1968) conclusion

Answer 6

Both hemispheres capable of acting independently (memories and awareness) and language centres on left side of the brain

Question 7

What was Gazzaniga’s (1983) study findings

Answer 7

• right hemisphere more able to recognize faces so right hemisphere specialised for facial recognition

Question 8

AO3 Strength point

Answer 8

Split brain research is supported from more recent studies which extends understanding of hemispheric specialisation

Question 9

AO3 Strength evidence

Answer 9

Luck (1989) - split brain patients faster at identifying odd one out of similar objects - specialised processing abilities of the the hemispheres

Question 10

AO3 Limitation point

Answer 10

Less lateralised with aging

Question 11

AO3 Limitation evidence

Answer 11

Szaflorski (2006) - language functions become more lateralised to left hemisphere during childhood and adolescence but trend reverses after 25 - Lateralization declines in subsequent decades