Localisation of Brain Functions

Question 1

What is meant by localisation of function in the brain?

Answer 1

Localisation of function is the idea that specific cognitive processes and behaviours are associated with specific areas of the brain. This theory opposes the holistic view that all parts of the brain were involved in processing thought and action.

Question 2

motor area

Answer 2

back of frontal lobe. controls voluntary movement in opposite sides of the body. damage may result in loss of control over fine movements

Question 3

somatosensory area

Answer 3

front of parietal lobe. separated from motor area by central suclus. sensory info from skin is represented- the more sensitive the area, the more space is devoted

Question 4

visual area

Answer 4

in the occipatal lobe. each eye sends info from the right VF to the left visual cortex and from the left VF to the right visual cortex. damage to the LH causes blindness to both eyes

Question 5

auditory area

Answer 5

in the temporal lobe. analyses speech based info. damage can cause partial hearing loss and damage to specific areas may affect the ability to understand language

Question 6

Broca’s aphasia

Answer 6

slow, laborious speech that lacks fluency

Question 7

Wernicke’s aphaisa

Answer 7

production of nonsense words- fluent but meaningless

Question 8

strength- high scientific credibility

Answer 8

supportive evidence from brain scans- Pearsons et al used brain scans to show that Wernickes was active during a listening task and Brocas during a reading task. this highlights how specific areas of the brain are responsible for diff cognitive functions = demonstrates reliability of theory- objective methods

Question 9

weakness- contradictory evidence

Answer 9

challenged by Lashley’s research- removed 10-15% of cortex from rats learning to navigate a maze. he found no area to be more important than any other in the ability to learn maze. this suggests higher cognitive functions are not localised but are distributed holistically. findings show learning requires whole cortex= undermines theory- not fully explained

Question 10

strength- high validity

Answer 10

neurosurgical procedures- cingulotomy involves removing specific areas of the brain to treat disorders like OCD/depression. 44% OCD patients- process was successful at reducing symptoms, demonstrating impact of targetting specific areas. this provides support for localisation theory= functional specificity

Question 11

weakness- alternate theory of plasticity

Answer 11

law of equipotentiality states that surviving brain circuits can chip in to help with recovery of lost functions. this shows all parts of the brain can perform all functions. plasticity suggests brain is more flexible than previously thought as it can reorganise itself and compensate for damage= contradicts localisation theory that says damage impacts overall

Question 12

case study- phineas gage

Answer 12

metal rod passed through his frontal lobe, causing a disorder. this led to him not being able to function as he was before- becoming impatient and rude. this is because of specific areas controlling specific functions that were damaged