localisation of function in the brain + hemispheric lateralisation

Question 1

what is meant by localisation ?

Answer 1

• specific areas of the brain are associated with particular physical and psychological functions

Question 2

What does
Phineas Gage’s case provide evidence for ?

Answer 2

• this case provides early evidence to support localisation of function
• since Gage’s brain damage was located in the frontal lobe , his case study offered evidence that the frontal lobe is related to personality

Question 3

why do we have to be cautious when using Gage’s case study ?

Answer 3

• because the results cannot be generalised to the whole population because this is such a unique injury

Question 4

what is meant by lateralisation ?

Answer 4

• the dominance of one hemisphere of the brain for particular physical and psychological functions

Question 5

what is meant by the hemispheres ?

Answer 5

• the brain is divided into 2 hemispheres: the left and the right
• each hemisphere is considered to be responsible for specific functions

Question 6

what is the main difference between the hemispheres concerned with ?

Answer 6

language
- as language areas are mostly found in the left hemisphere

Question 7

Broca’s area
location
function
damage effect

Answer 7

1. located in the left frontal lobe
2. speech production + covert thought into speech
3. aphasia (speech lacks fluency and is slow)

Question 8

Wernickle’s area
location
function
damage effect

Answer 8

1. located in the left temporal lobe
2. speech comprehension + recognition of spoken word
3. difficult to understand others + producing meaningful speech

Question 9

frontal lobe function ?

Answer 9

• movement
• mood
• problem solving
• concentrating / thinking
• behaviour
• personality

Question 10

temporal lobe function ?

Answer 10

• hearing
• language
• memory

Question 11

Brain stem function ?

Answer 11

• consciousness
• breathing
• heart rate

Question 12

cerebellum function ?

Answer 12

• posture
• balance
• co ordination of movement

Question 13

occiptal lobe function >

Answer 13

• vision
• perception

Question 14

parietal lobe function ?

Answer 14

• sensation
• language
• attention
• perception
• body awareness

Question 15

blurt phineas Gage study

Question 16

lashley’s research AIM

Answer 16

to show how the processes involved in learning are not localised but distributed in a more holistic way in the brain

Question 17

Lashley’s method

Answer 17

Lashley removed areas of the cortex in rats that were learning a maze
no area was proven to be more important than any other area in terms of the rats ability to learn the maze

Question 18

what percentage of the rats brain did Lashley remove?

Answer 18

between 10 % and 50%

Question 19

Lashley research results

Answer 19

the process of learning appeared to require every part of the cortex, rather than being confined to a particular area

Question 20

Lashley research conclusion

Answer 20

• this seems to suggest that learning is too complex to be localised and requires the involvement of the whole brain

Question 21

Hubel and Wiesel research AIM

Answer 21

to demonstrate the effect of visual impairment on the visual system

Question 22

Hubel and Wiesel
- method

Answer 22

• one eyelid was sutured shut on newborn kittens
• the kitten was allowed to grow up that way, and when it reached adulthood (around 6 months ), its eyelid was opened again
• recording were made of the electrophysiological activity in each kittens eyes

Question 23

Hubel and Wiesel
results

Answer 23

• recordings showed an abnormally low number of neurons reacting in the eye that had been sutured shut
• and an abnormally high number in the other eye
• macroscopic observation of the visual cortex showed that the ocular dominance columns for the eye that had been left open had grown larger, while those for the eye that had been closed had shrunk

Question 24

Hubel and Wiesel
conclusion

Answer 24

• showed that if a kitten is deprived of normal visual experience during a critical period at the start of its life, the circuitry of the neurons in its visual cortex is irreversibly altered

Question 25

Hubel and Wiesel AO3

Answer 25

• later experiments showed that suturing a cats eye shut had no effect on its visual cortex unless the visual deprivation took place in the first 3 months of the cats life