Localisation

Question 1

define localisation of function

Answer 1

The theoty that different areas of the brain are responsible for specific behaviours, processes or activities.

Question 2

split the brain into 3 concentric layers

Answer 2

• the cerebrum
• the limbic system
• the central core

Question 3

What is meant by the central core

Answer 3

Also known as the brain stem. Its structure includes the hypothalamus.

The central core regulates primative and involuntary behaviours such as breathing, sleeping, sneezing. It also regulates the endocrine system in order to maintain homeostasis.

Question 4

define homeostasis

Answer 4

the process by which the body maintains a constant physiological state.

Question 5

what is meant by the limbic system

Answer 5

Around the central core of the brain, interconnected with the hyippothalamus, it contains structures such as the hippocampus.
It controls emotions.

Question 6

What is mean by the cerebrum

Answer 6

It has the outermost layer known as the cerebral cortex. Each of our sensory systems sends messages to and from this cerebral cortex.
The cerebrum is made up of he left and right hemispheres which are connected by the corpus callosum.
The cerebrum regulates our higher intellectual processes.

Question 7

what is the corpus callosum

Answer 7

A bundle of fibres that connect the left and right hemispheres and as a result enables messages to enter one hemisphere and be conveyed to the other.

Question 8

How are hemispheres futher divided

Answer 8

Each hemisphere is further divided into four lobes:
- the frontal lobe
- the parietal lobe
- the temporarl lobe
- the occipital lobe

Question 9

general

What is the role of the parietal lobe

Answer 9

it is the location for sensory and motor movements

Question 10

general

what is the role for the occipital lobe

Answer 10

it is the location for vision

Question 11

general

what is the role of the frontal lobe

Answer 11

it is the location for awareness of what we are doing within out environment (our consciousness)

Question 12

general

What is the role of the temporal lobe

Answer 12

It is the location for auditory ability and memory acquisition

Question 13

Where is the motor cortex located in the brain

Answer 13

in the rear of the frontal lobe

Question 14

what is the motor cortex responsible for

Answer 14

the generation of voluntary motor movements

Question 15

explain the location of the motor cortex in relation to the hemispheres and its composition and the consequences of these.

Answer 15

Both hemispheres of the brain have a motor cortex. The motor cortex in one hemisphere controls the muscles on the opposite side of the body.
Different parts of the motor cotrex exert control over different parts of the body. These regions are arranged logically next to each other i.e. region to control the foot is next to the region to control the leg.

Question 16

where is the somotasensory cortex located in the brain

Answer 16

in the parietal lobe

Question 17

What is the somatosensory cortex responsible for

Answer 17

• detects sensory events, arising from different regions of the body.
• it produces the sensations of touch, pressure, pain and temperature, which it then localised to specific body regions.

Question 18

explain the location of the somatosensory cortex in relation to the hemispheres.

Answer 18

Both hemispheres have a somatosensory cortex, each side recieves information from the opposite side of the body.

Question 19

Where is the visual cortex located in the brain

Answer 19

in the occipital lobe

Question 20

what is the visual cortex responsible for

Answer 20

recieving and processing visual information

Question 21

Explain how the visual cortex fuctions

Answer 21

Nerve impulses from the retina transmit to the brain via the optic nerve.
The visual cortex spans both hemispheres with the opposite side side inputting the other’s infomation.
There are lots of different areas for different visual information i.e. colour, shape, movement.

Question 22

Where is Broca’s area located

Answer 22

in the frontal lobe in the left hemisphere

(of most people)

Question 23

What is Broca’s area responsible for

Answer 23

speech production

Question 24

Give evidence for Broca’s area

Answer 24

Patient ‘Tan’
couldnt speak but could understand spoken language. However he couldnt express himself verbally or in writing.
Other patients also had problems - all had lesions in the posterior portion of the frontal lobe of the left hemisphere.

Question 25

Where is Wernicke’s area located in the brain

Answer 25

posterior portion of the left temporal lobe

posterior = towards the back

Question 26

What is Wernicke’s area responisble for

Answer 26

understanding langauge

Question 27

Explain how langauage functions in the brain

Answer 27

Language involves seperate motor and sensory regions located in different cortical regions.
The motor region (in Broca’s area) is close to the area that controls the mouth, tongue and vocal cords.
The sensory region (in Wernicke’s area) is close to the regions of the brain responsible for auditory and visual input. Input from these regions is thought to be transferred to Wernicke’s area where it is recognised as a language and associated with meaning.
There is a neural loop running between Broca’s area and Wernickes’ area.

Question 28

What are Wernicke’s and Broca’s areas responsible for

Answer 28

• Wernicke’s = langauge comprehention
• Broca’s = language production

Question 29

What is the possible evidence for and against localisation

Answer 29

Broca = for
Lashley 1950 = against
Petersen et al 1988 = for

Question 30

outline Lashley 1950

Answer 30

Lashley removed areas of the cortex (between 10-50%) in rats that were learning the route through a maze. Lashley found that no area was. proven to be more important than any other area in terms of the rats’ ability to learn the route. Instead the process of learning seemed to require every part of the cortex rather than being confined to a particular area. This suggests that higher cognitive processes, such as learning , are not localised but distributed in a more holistic way in the brain.

Question 31

Outline Petersen et al 1988

Answer 31

Petersen et al. used brain scans to demonstrate how Wernicke’s area was active during a listening task and Broca’s area was active during a reading taks. Showing that some everyday tasks are localised brain fuctions.

Question 32

Give the evalutory strengths of localisation

Answer 32

• Supported by scientific research
  ⤷Broca, Petersen 1988

Question 33

Give evaluatory weaknesses of localisation

Answer 33

• (Broca’s) research was on a small sample of abnormal brain structures and then generalised to typical individuals.
• functions such as language are too complex to be assigned to just one area and instead involve a network of brain regions.