Biopsychology - Localisation of function in the brain and hemispheric lateralisation

Question 1

Localisation of function

Answer 1

• Theory that different areas of brain are responsible for different behaviours, processes or activities
• Contrasts with holistic view of brain
• If certain area of brain is damaged, the function associated with the area will be affected

Question 2

Hemispheric lateralisation: Split brain

Answer 2

• Idea that the two halves of the brain are functionally different and each hemisphere has specialisations.
• Left dominant for language, right excels visual motor tasks
• 2 hemispheres of brain connected by nerve fibres called corpus callosum

Question 3

Sperry (1968)

Answer 3

• Aim: To assess abilities of separated brain hemispheres
• Procedure:
  > Patients sat in front of board with rows of lights and asked to stare at middle point
  > Lights flashed across right and left visual field. Reported lights only flashed up on right side of board
• Findings: When right eye covered and lights flashed left side of visual field, no light seen. However, could point to light that lit up when asked

Question 4

Motor and Somatosensory areas

Answer 4

• The motor cortex controls voluntary movements

- Different areas of motor cortex controls different parts of body

Question 5

Visual centres

Answer 5

• Processing of visual information starts when light enters the eye and strikes photoreceptors on retina at back of eye
• Right hemisphere visual cortex processes visual info received by right eye and vice versa

Question 6

Auditory centres

Answer 6

• Processing of auditory info begins in inner ears cochlea where sound waves are transferred into nerve impulses that travel to brain stem where sound is processed

Question 7

Language centres

Answer 7

• Broca’s area main centre of speech production
• Broca’s area may also be involved with complex cognitive tasks like maths problems
• Wenicke’s area is also in the left hemisphere and is concerned with speech comprehension

Question 8

Plasticity

Answer 8

• Brains ability to change and adapt in reaction to the environment and through experience
• Learning a new skill develops neural connections in the related area of the brain
• If area of brain is damaged, plasticity allows the brain to form new neural connections and adapt as a result of the damaged area.