Localisation of Function

Question 1

What does localisation theory state?

Answer 1

Functions are controlled by specific areas of the brain.

Question 2

What does holistic theory state?

Answer 2

The whole brain is responsible for carrying out functions.

Question 3

Name the 4 lobes in the brain.

Answer 3

Frontal
Parietal
Temporal
Occipital

Question 4

Name the hemispheres the brain is divided into.

Answer 4

Left
Right

Question 5

What does contralateral wiring mean?

Answer 5

Each half of the brain is responsible for the opposite side of the body. This means the RH controls the left side of the body and vice versa.

Question 6

Name the structure the brain is surrounded by.
What does it do?

Answer 6

The cerebral cortex.
Allows for complex processes such as thinking.

Question 7

Where is the frontal lobe found in the brain?

Answer 7

At the front in both hemispheres.

Question 8

Name the 2 areas the frontal lobe contains.

Answer 8

Motor area
Broca’s area

Question 9

What does the motor area do?

Answer 9

Controls voluntary movement.

Question 10

What would happen if damage to the motor area occurred?

Answer 10

Issues with fine motor skills in the opposite side of the body to which the affected area is.

Question 11

What does Broca’s area do?

Answer 11

Controls fluency of speech.

Question 12

What would happen if damage to Broca’s area occurred?

Answer 12

Damage leads to Broca’s aphasia, where you struggle to form fluent sentences.

Question 13

Where is the temporal lobe found?

Answer 13

At the bottom of the brain, below the parietal lobe.

Question 14

Name both components of the temporal lobe.

Answer 14

Auditory area
Wernicke’s area

Question 15

What does Wernicke’s area do?

Answer 15

Ensures speech is logical and understandable

Question 16

What happens when damage to Wernicke’s area occurs?

Answer 16

Wernicke’s aphasia, where your speech does not make sense and contains random words.

Question 17

What does the auditory area do?

Answer 17

Analyses incoming speech information into the brain.

Question 18

What happens if damage to the auditory area occurs?

Answer 18

Damage leads to partial hearing loss.

Question 19

Name a component of the parietal lobe.

Answer 19

Somatosensory area.

Question 20

What does the somatosensory area do?

Answer 20

Processes sensory information from the skin.

Question 21

What would happen if damage to the somatosensory area occurred?

Answer 21

Damage may lead to feelings of numbness on the skin, particularly in the hands and feet.

Question 22

Name a component of the occipital lobe.

Answer 22

Visual area.

Question 23

What does the visual area do?

Answer 23

Processes information from each visual field from the eyes.

Question 24

What happens if damage to the visual area occurs?

Answer 24

Vision loss in the opposite visual field to which the damage in the hemisphere is in.

Question 25

Which 2 components on the brain are not found in both hemispheres?
Instead, which hemisphere are they found in?

Answer 25

Broca and Wernicke’s areas
They are both found in the left hemisphere only.

Question 26

Explain the strength that there is research support for localisation from brain scans.
Use examples from Petersen (listening tasks) and examples from Tulving (semantic/episodic memories).
Why are their findings valid?

Answer 26

For example, Petersen used brain scans to demonstrate how Wernicke’s area was active during a listening task and Broca’s area was active during a reading task. Additionally, Tulving’s research revealed that semantic and episodic memories reside in different parts of the prefrontal cortex. These findings are valid because brain scans produce objective and unbiased data as they cannot be manipulated. This therefore shows that brain function is localised to different regions.

Question 27

Explain the strength of there being research support from aphasia studies on the Tan case study from Broca.
Use the counterpoint of issues with case studies and contradictions about language localisation.

Answer 27

Broca conducted a case study on ‘Tan’, who after a post-mortem, was discovered to have a lesion in Broca’s area. He struggled with his speech and could only say the word ‘tan’, so this provides evidence to show that Broca’s area controls speech. However, there are issues with case studies as they involve detailed reports on a person or small group. This means that findings may not be generalisable to wider populations, so population validity is therefore lacked. Additionally, there is research that contradicts language localisation. Language streams have been found across the cortex, including in the RH and sub cortical regions. This suggests that language may not be localised.

Question 28

Explain the strength of research support from the Phineas Gage case study.

Answer 28

Phineas Gage experienced a metal pole passing behind his eye, through his skull and left frontal lobe, which contains Broca’s area. Before the accident, he was calm and polite, but afterwards, he became rude and vulgar. This suggests that the frontal lobe controls personality and mood. Also, the vision in his remaining eye was perfect. This is because vision is controlled by the occipital lobe in the back of the brain, which was unaffected. This therefore provides more evidence that brain function is localised.

Question 29

Explain the limitation of there being evidence that brain function isn’t localised from the Italian boy case study (Danelli) and plasticity.

Answer 29

Danelli examined the ‘Italian boy’ who had his LH removed aged 2.5yrs. By age 17, his language performance compared to healthy adult controls. This shows that his RH had taken over language functions (recruitment of homologous areas). Plasticity would suggest that the brain can adapt to ensure that important functions can still be carried out, even when there is damage. This therefore provides evidence for holistic theory as opposed to localisation theory, which would suggest that if the LH were lost, then language and speech would also be lost.