Biopsychology: Localisation Of Function

Question 1

Phineas Gage Case Study.

Answer 1

• Phineas Gage had meter-long iron through his left cheek and exiting his skull from top of his head taking a proportion of his brain with it - most of his left frontal lobe.
• Gage survived damage caused a change of his personality (calm to quick tempered).
• This case study suggested that the frontal lobe may be responsible for regulating mood.

Question 2

What Are The Two Different Theories Of Brain Function?

Answer 2

• The holistic theory argued that all parts of the brain are involved in the processing of thought and action.
• The localisation of function theory argued that specific areas of the brain are associated with particular physical and psychological function. Damage to these areas cause consequence for behaviour.

Question 3

What Is The Cerebral Cortex.

Answer 3

• The cerebral cortex which covers the inner parts of the brain, lies in-between the two hemispheres.
• Cortex is 3mm thick and what separates us from other animals because human cortex is much more developed.
• Cortex in both hem is subdivided into 4 lobes named after the bones beneath which they lie: frontal lobe, the parietal lobe, the occipital lobe, temporal lobe - each having a different function.

Question 4

What Is The Motor Cortex? (Location, Role, Damage)

Answer 4

• Location: At the back of the frontal lobe.
• Role: Controls voluntary movement in the contralateral side of the body.
• Damage: Loss of fine movements.

Question 5

What Is The Somatosensory Cortex? (Location, Role, Damage)

Answer 5

• Location: At the front parietal lobe.
• Role: Represents sensory information from skin. The more sensitive an area, the more space it takes up in the somatosensory cortex.
• Damage: Loss of senses.

Question 6

What Is The Visual Cortex? (Location, Role, Damage)

Answer 6

• Location: In the occipital lobe.
• Role: Information from RVF is sent to LVC and vice versa.
• Damage: Loss of specific areas of the visual field.

Question 7

What Is The Auditory Cortex? (Location, Role, Damage)

Answer 7

• Location: In the temporal lobe.
• Role: Analyse speech-based information.
• Damage: Partial hearing loss.

Question 8

What Is The Wernicke’s Area? (Location, Role, Damage)

Answer 8

• Location: Left temporal lobe.
• Role: Responsible for language comprehension.
• Damage: People produce nonsense words.

Question 9

What Is The Broca’s Area? (Location, Role, Damage)

Answer 9

• Location: Small area of the left frontal lobe.
• Role: Responsible for speech production.
• Damage: Slow speech that lacks fluency.

Question 9

The Language Area - Broca And Wernicke’s Area.

Answer 9

• Broca an Wernicke’s area are examples of localisation.
• They are both located in specific areas of the brain.
• However, they both are only occur in the left hemisphere (specialised to one hemisphere is known as lateralisation).

Question 10

Localisation Of Function Evaluation: Strength - Brain Scan Support.

Answer 10

• There is brain scan evidence to support the idea that functions are localised.
• Petersen et al used brain scans to demonstrate Wernicke’s area was active during a listening task and Broca’s area was active during a reading task.
• This suggests that these parts of the brain have different functions.
• Therefore increasing the validity of the concept localisation.

Question 11

Localisation Of Function Evaluation: Strength - Neurosurgical Evidence.

Answer 11

• There is neurosurgical evidence to support that functions are localised.
• Dougherty et al reported on 44 OCD patients who had undergone a cingulotomy.
• A post-surgical follow up after 32 weeks showed a third of patients had successful response to the surgery and 14% a partial response.
• This suggests that symptoms and behaviours associated with OCD are localised.

Question 12

Localisation Of Function Evaluation: Strength - Case Study Evidence.

Answer 12

• There is case study evidence to support that functions are localised.
• Phineas Gage was involved in an accident where his left frontal lobe was damaged, and his personality changed to quick tempered.
• This suggests that personality and temperament is localised within the frontal lobe.

Question 13

Localisation Of Function Evaluation: Weakness - Higher Cognitive Functions Holistic.

Answer 13

• There is evidence to suggest some higher cognitive functions are distributed in a more holistic way in the brain.
• Lashley removed areas of the cortex in rats that were learning a maze.
• No area was proven to be more important than any other in terms of the rat’s ability to learn the maze.
• This suggests that learning is too complex to be localised and involves the whole brain.

Question 14

Localisation Of Function Evaluation: Weakness - Functional Recovery.

Answer 14

• Functional recovery shows that localisation of function can change.
• There is a girl who lives with only half a brain as after illness or accident the rest appears able to reorganise itself in an attempt to recover the lost function.
• This supports that the holistic view of functioning rather than the localisation view.