localisation of function in the brain

Question 1

localisation versus holistic theory

Answer 1

19th century scientists Broca and Werncike discovered that specific areas of the brain are associated with particular physical and psychological functions

before this scientists generally supported the holistic theory of the brain - meaning that all parts of the brain were involved in the processing of thought and action

Brocas and Werncike argued for localisation of function

this is the idea that different parts of the brain perform different tasks and are involved with different parts of the body

if certain area of the brain becomes damaged through illness or injury the function associated with that area will also be affected

Question 2

hemispheres of the brain

Answer 2

main part of the brain - cerebrum is divided into two symmetrical halves closed left and right hemisphere

some of our physical and psychological functions are controlled or dominated by a particular hemisphere - lateralisation

rule - activity on the left hand side of the body is controlled by the right hemisphere

language is linked to the left hemisphere

Question 3

cerebral cortex

Answer 3

the outer layer of both hemispheres

subdivided into four centres called the lobes of the brain

frontal lobe
parietal lobe
occipital lobe
temporal lobe

Question 4

motor area

Answer 4

at the back of the frontal lobe

in both hemispheres

contorls voluntary movement in the opposite side of the body

damage to this area of the brain may result in a loss of control over fine movements

Question 5

somatosensory area

Answer 5

at the front of the pareital lobe

where sensory information form the skin is represented such as touch heat and pressure

the amount of somatosensory area devoted to a particular body part denotes its sensitivity for instance receptors of out face and hands occupy over half the somatosensory area

Question 6

visual centre

Answer 6

each eye sends info from the right visual field to the left visual cortex

from the left visual field to the right visual cortex

means that the damage to the left hemisphere can produce blindness in part of the right visual filed of both eyes

Question 7

auditory centre

Answer 7

analyses speech based information

damage may produce partial hearing loss

the more extensive the damage the more extensive the loss

damage to a specific area of the temporal lobe wernickes area may affect the ability to comprehend language

Question 8

language centre - broca’s area

Answer 8

the other areas are found in both hemispheres

language is restircted to the left side of brain

Broca’s area - small area in the left frontal lobe

responsible for speech production

damage to broca’s area causes brocas aphasia - speech is slow and laborious and lacks fluency

Question 9

language centre - werncike

Answer 9

l;eft temporal lobe

responsible for language understanding

results in wernickes aphasia when damaged - will often produce nonsense words as part of the content of their speech

Question 10

strength

Answer 10

evidence from neurosurgery

damage to areas of the brain has been linked to mental disorders

Neurosurgery is a last resort method for treating some mental disorders

targeting specific areas of the brain which may be involved

example - Dougherty et al
cingulotomy involves isolationg a region called the cingulate gyrus which has been implicated to OCD

shown to improve the symptoms of OCD

The success of these procedures suggests that behaviours associated with serious mental disorders may be localised

Question 11

strength

Answer 11

evidence from brain scans

supports the idea that many everyday brain functions are localised

Peterson et al used brain scans to demonsatrate how Wernickes area was active during a listening task

broca’s area was active during a reading task

confirm localised areas for everyday behaviours

therefore objective methods for measuring brain activity have provided sound scientific evidence that many brain functions are localised

Question 12

limitation

Answer 12

language localisation questioned

lana greg may not be localised just to brocas and wernickes area

Dick and Tremblay

advances in brain imaging techniques such as fMRI mean that neural processes in the brain can be studied with more clarity

seems that language function is distributed far more holistically in the brain than was first thought

so called language streams have been identified across the cortex including brain regions in the right hemisphere

suggests that rather than being confined to a couple of key areas language may be organised more holistically on the brain

contradict localsiation theory