Localisation of function in the brain

Question 1

What is localisation?

Answer 1

The theory that specific areas of the brain are associated with particular physical and physiological functions

Question 2

What is hemispheric lateralisation?

Answer 2

The dominance of 1 hemisphere of the brain for particular physical and physiological functions

Question 3

What is the primary motor cortex and where is it located?

Answer 3

1. Responsible for the generation of voluntary motor movements
2. Located in frontal lobe

Question 4

What does contralateral mean?

Answer 4

1. The right frontal lobe controls movement on the left side of the body and vice versa (controls the opposite side)
2. Any damage to one side of the brain in this area (e.g. through a stroke) will affect the control of movement on the opposite side of the body

Question 5

If something is somatotopically organised, what does it mean?

Answer 5

There’s a point for point correspondence of a body area to a specific point on the CNS

Question 6

What does the somatosensory cortex do and where is it located?

Answer 6

1. Located in parietal lobe
2. Using sensory information from the skin and produces sensations of touch, pressure, pain, temperature which then localises to specific body regions
3. Both hemispheres have a somatosensory cortex which is contralateral

Question 7

What is the frontal lobe, its cortex, and its location?

Answer 7

1. Located opposite the cerebellum
2. Responsible for awareness (consciousness)
3. Cortex is the motor cortex (responsible for motor movements)

Question 8

What is the parietal lobe, its cortex, and its location?

Answer 8

1. Responsible for sensory feeling (touch, pressure, pain, temperature)
2. Cortex is the somatosensory cortex
3. Located next to the frontal lobe

Question 9

What is the occipital lobe, its cortex, and its location?

Answer 9

1. Located next to the parietal and temporal lobe/ slightly above the cerebellum
2. Responsible for vision (shape colour, movement)
3. Cortex is the visual cortex

Question 10

What is the temporal lobe, its cortex, and its location?

Answer 10

1. Responsible for auditory ability
2. Cortex is the auditory cortex
3. Located above the cerebellum, underneath the frontal and parietal lobe, next to the occipital lobe

Question 11

What is the visual cortex and where is it located?

Answer 11

1. Located in the occipital lobe of the brain
2. Visual cortex spans both hemispheres and is contralateral
3. Contains several different areas with each processing different types of visual information: colour, shape, movement
4. Damage to visual cortex can cause cortical blindness

Question 12

What is the auditory cortex and where is it located?

Answer 12

1. Located within the temporal lobes in both hemispheres of the brain
2. It’s process is contralateral (information from the right ear travels primarily to the left auditory cortex and vice versa)
3. Damage to the auditory cortex produces difficulties in processing and understanding sounds rather than total deafness
4. Recognises and interprets sound

Question 13

If the point is:

A weakness of localisation of function in the brain is that much of the research such as Wernicke’s and Broca’s areas comes from case study evidence.

What is the evidence, explanation and link?

Answer 13

Evidence- These studies involve individuals and investigate the effect of damage to their brain on their cognitive functions.

Explanation- However, these effects may be specific to the individuals concerned and may not be generalisable to others.

Link- This could imply that there may be issues when generalising findings from case studies to all brains.

Question 14

If the point is:

Another weakness of localisation of function in the brain is that the plasticity of brain function argues that localisation of function is largely incorrect.

What is the evidence, explanation and link?

Answer 14

Evidence- More recent research into the plasticity of the brain shows that key areas for key functions can be changed in the light of injury/ functional recovery after brain injury.

Explanation- It may be the case that simpler functions are likely to be more localised in the brain, e.g. motor control, but more sophisticated aspects of the brain can swap and change if necessary.

Link- This could mean that the localisation of function in the brain explanation is not a fully reliable and credible explanation to be used within psychology.

Question 15

If the point is:

A strength of localisation of function in the brain is that there’s research to support it from human clinical case studies of the loss of specific abilities after restricted brain damage.

What is the evidence, explanation and link?

Answer 15

Evidence- For example, receptive aphasia following damage to Wernicke’s area and amnesia following damage to specific areas of the hippocampus.

Explanation- HM damaged his hippocampus during surgery for epilepsy and created irreversible damage to memory.

Link- This suggests that research has shown support for the brain being localised, validating the idea.

Question 16

If the point is:

Another weakness of localisation of function in the brain is that the holistic theory of brain function argues that it is largely incorrect.

What is the evidence, explanation and link?

Answer 16

Evidence- Lashley’s research on rats supports the concept of equipotentiality of the cortex and suggests that very few functions of the brain are completely localised. He made lesions in different areas of the brains of rats who were put into a maze and found large lesions on visual areas impaired maze learning, but smaller lesions covering the same brain area had no effect. He concluded that functions such as learning were spread widely across brain areas and were not localised to specific regions.

Explanation- It may be the case that simpler functions are likely to be more localised in the brain, e.g. motor control as compared with e.g. personality (consciousness).

Link- This shows that not all functions are localised, meaning the theory may be limited to explaining how the brain works.

Question 17

What are the evaluation points for localisation of function in the brain?

Answer 17

– Much of the research, such as Broca’s and Wernicke’s area come from case study evidence

– The plasticity of brain function argues that localisation of function is largely incorrect

+ There’s research to support it from human clinical case studies of the loss of specific abilities after restricted brain damage

– The holistic theory of brain function argues that it is largely incorrect