localisation of function in the brain

Question 1

what is localisation of function

Answer 1

the theory that diff areas of the brain are responsible for diff behaviours, processes or activities

Question 2

hemispheres of the brain

Answer 2

the brain is divided into 2 hemispheres
- left hemisphere controls right side of body
- right hemisphere controls left side of body

Question 3

what is lateralisation

Answer 3

the idea that some of our physical and psychological functions are controlled by a particular hemisphere

Question 4

cerebral cortex

Answer 4

• covers inner parts of the brain
• about 3mm thick
• much more developed than other animals

Question 5

the 4 lobes

Answer 5

• frontal lobe
• parietal lobe
• occipital lobe
• temporal lobe

Question 6

the motor area

Answer 6

• located at the back of the frontal lobe
• controls voluntary movement
• damage may cause loss of control over fine movements

Question 7

the somatosensory area

Answer 7

• located at the front of both parietal lobes
• where sensory info from the skin is represented
• receptors for our face and hands occupies over half of the area so they’re more sensitive

Question 8

the visual area

Answer 8

located in the occipital lobe at the back of the brain
- each eye sends info to its corresponding cortex
> right visual field to left visual cortex
- damage to left hem can = blindness in part of the right visual field in both eyes

Question 9

the auditory area

Answer 9

• located in the temporal lobe
• analyses speech based info
• damage may = partial hearing loss
  > the more extensive the damage the worse the loss

Question 10

Wernicke’s area

Answer 10

region in left temporal lobe
- responsible for language comprehension
- damage results in Wernicke’s aphasia

Question 11

what is Wernicke’s aphasia

Answer 11

production of nonsense words as part of the content of their speech

Question 12

Broca’s area

Answer 12

located in the left frontal lobe
- responsible for speech production
- damage results in Broca’s aphasia

Question 13

what is Broca’s aphasia

Answer 13

characterised by slow, laborious and lack of fluency in speech

Question 14

supporting evaluation for localisation

Answer 14

1. Phineas Gage
2. brain scan evidence

Question 15

Phineas Gage

Answer 15

P - real life example supporting localisation
E - pole entered left cheek and went behind left eye, damaged left frontal lobe
> frontal cortex associated w planning, control…
E - personality changed, used to be calm + reserved, now quick tempered + rude
CA - small, unique sample not generalisable
L - still provided evidence and hard to find non-unique sample

Question 16

brain scan evidence

Answer 16

• Peterson et al
• Tulving et al

Question 17

brain scan evidence for localisation

Answer 17

P - research support for localisation
E - P used brain scans to demonstrate how:
> Wernicke’s area was active during listening tasks
> Broca’s area was active during reading tasks
- T found semantic and episodic memories reside in diff parts of the pre-frontal cortex
E - suggested these areas had diff functions
L - wealth of evidence providing support for idea that many neurological functions are localised, esp language and memory

Question 18

opposing evaluation for localisation

Answer 18

Lashley’s research

Question 19

Lashley’s research

Answer 19

P - opposing evidence for localisation
E - removed areas of the cortex (10-50%) in rats that were learning in a maze, process of learning required every part of cortex
E - no area proven to be more important than another in their ability to learn the maze
CA - careful when extrapolating to humans
L - suggests higher cognitive functions like learning are not localised but distributed holistically

Question 20

how is language both localised and lateralised

Answer 20

• localised to specific areas (Broca’s and Wernicke’s)
• lateralised to the left hemisphere