Hemispheric Lateralisation

Question 1

What is the definition of Hemispheric lateralisation?

Answer 1

The idea that the brain’s two hemispheres are responsible for different functions

Question 2

What are the lateralised (left) and non-lateralised (right) functions of the brain?

Answer 2

Lateralised: Language,
Non-lateralised: Motor, Somatosensory, Auditory, Vision

Question 3

What is contra-lateral control?

Answer 3

The idea that each hemisphere controls the opposite side of the body

Question 4

What is the role of the corpus callosum in the brain?

Answer 4

This is a nerve fibre that connects the left and right hemisphere and allows for communication between the both.

Question 5

Outline Sperry’s split-brain research (KS)

Answer 5

Aim: to study the effects of hemisphere disconnection, and to show that each hemisphere has different functions
Procedure: His sample was 11 individuals with a severed corpus callosum (split brained patients), he would then present images/words to one visual field of the patient at a time.
Findings: the right visual field (left hemisphere) could name the object that it saw. The left visual field (right hemisphere), however, could not name what it saw but could draw or pick it up.
Conclusions: The hemispheres have specialised functions and cannot communicate when separated

Question 6

Evaluate Sperry’s split brain research

Answer 6

Strengths:
- Lab experiment
- Highly useful (understanding brain damage cases)
Limits:
- Small sample size
- Artificial tasks

Question 7

What are the strengths and limits of HL

Answer 7

Strengths:
- Supporting research (Gereon Fink - PET scans)
- Supporting research (Gazzaniga - L and R function distinctly)
Limits:
- Alternative research (Jared Nielsen - no overall dominant hemisphere)