Localisation of the functions in the brain

Question 1

What is the localisation of the functions of the brain theory and who developed it?

Answer 1

Broca and Wernicke
Suggests different areas of the brain are responsible for specific functions

Question 2

What is the holistic theory of the brain?

Answer 2

All thoughts of the brain were involved in the process of thought and action.

Question 3

What is lateralisation?

Answer 3

Some of our physical and psychological functions are controlled by 1 particular hemisphere
Right - controls activity on left side of body
Left - controls activity on right side of body

Question 4

What is the cortex?

Answer 4

Surface layer of the brain
Referred to as grey matter (mostly cell bodies)
2-4 mm thick
Folded for extra surface area for processing
White matter - mostly myllenated axons

Question 5

What is the cortex of both hemispheres subdivided into?

Answer 5

Frontal
Parietal
Occipital
Temporal

Question 6

What is a lobe?

Answer 6

Part of an organ that is separate some way from the rest
Each associated with different function

Question 7

What is a the back of the frontal lobe (in both hemispheres)?

Answer 7

The motor area
Controls voluntary movement in opposite side of the body
Damage - lead to loss of muscle function or severe - paralysis
Opposite side of the body
Contralateral

Question 8

What is at the front of both parietal lobes?

Answer 8

Somatosensory area
Sensory information from skin is represented
The amount of somatosensory area devoted to a particular body part - represents its sensitivity
Damage - loss of sensation, ignoring areas of the body (neglect syndrome)
Contralateral

Question 9

How is the somatosensory area separated from the motor area?

Answer 9

a ‘valley’ called central sulcus

Question 10

What is in the occipital lobe at the back of the brain?

Answer 10

Visual area/cortex
Each eye sends info from right visual field - left visual cortex
Left visual field - right visual cortex
Damage - partial or complete loss of vision (cortical blindness), Damage to one cortex can lead to loss of vision in the opposite visual field

Question 11

What is in the temporal lobe?

Answer 11

Auditory area
Analyses speech based information
Damage - partial hearing loss
More extensive damage, the more extensive the loss
Cortical deafness
No damage to structure of ear

Question 12

What is hemispheric lateralisation?

Answer 12

Each hemisphere of the brain is specialised to perform different functions

Question 13

What does contralateral mean?

Answer 13

Each hemisphere of brain controls the opposite side of the body

Question 14

Where is the Brocas area found?

Answer 14

Left hemisphere only
Left frontal lobe

Question 15

What is the Brocas area responsible for?

Answer 15

Speech production

Question 16

What happens when the Brocas area is damaged?

Answer 16

Causes Brocas aphasia
Characterised by speech that is slow, laborious and lacking in fluency
Difficulty with prepositions and conjunctions (a, the, and)

Question 17

Who was Brocas most famous patient?

Answer 17

Tan
Which was the only word he could say

Question 18

Where is the Wernickes area found?

Answer 18

Left temporal lobe

Question 19

What was the Wernickes area responsible for?

Answer 19

Language understanding

Question 20

What happens if an individuals Wernickes area is damaged?

Answer 20

Wernickes aphasia
No problem producing language but severe difficulties understanding it
Eg. speech they produced was fluent but meaningless

Question 21

What is global aspasia?

Answer 21

Damage to both Brocas and Wernickes area
Inability to produce or understand speech

Question 22

What is a positive of localisation of the functions of the brain?

Answer 22

Clinical case study research
Demonstrated loss of certain functions if damage is caused to particular areas of the brain
Eg. Broca and Wernickes study (Aphasia) and Clive wearing (amnesia)
Suggesting functions are localised in these areas.

Question 23

What is a negative of localisation of the functions of the brain?

Answer 23

Use of case studies seen as scientific
Especially brain research - damage often covering multiple regions
MRI scans made of tans brain
Damage areas other than Brocas area

Question 24

What is another negative of localisation of functions in the brain?

Answer 24

Motor and somatosensory functions are highly localised
Systems like language are more distributed
Some systems like consciousness appear to not be localised at all
Suggesting correct approach for localised or holistic is dependent on the function
Also due to high connectivity of the brain no one area is important (argue no function is completely localised)

Question 25

What is research evidence against localisation of the functions of the brain?

Answer 25

Lashley 50 rats ran a maze Before and after areas of their brain cortex had been destroyed Found ability to successfully rerun the maze was affected by how much brain cortex was destroyed Not which parts were removed Suggesting high cognitive processes like memory and learning are not localised but distributed across the brain