Localisation of fucntion

what does anterior mean?

towards the front

what does posterior mean?

towards the back

what does superior mean?

above

what does inferior mean?

below

What is localisation of function?

theory that different areas of the brain are responsible for different behaviours, processes or activities

What are the 4 lobes of the brain?

frontal

parietal

temporal

occipital

Motor area:

1. Where?

2. Responsible for?

3. Damage may result in?

1. both hemispheres of posterior of frontal lobe

2. generation of voluntary movements in the opposite side of the body

3. partial loss of movement or paralysis

Somatosensory area:

1. Where?

2. Responsible for?

3. Damage may result in?

1. both hemispheres, anterior of parietal lobe, along the central sulcus region

2. sensory information from the skin (e.g. Heat, pressure)

3. partial loss of sensation

Visual area:

1. Where?

2. Responsible for?

3. Damage may result in?

1. occipital lobe (both hemispheres)

2. Visual info - info from right visual field goes to left hemisphere and vice versa

3. partial/full loss of sight

Auditory area:

1. Where?

2. Responsible for?

3. Damage may result in?

1. temporal lobe - both hemispheres

2. speech-based information

3. hearing loss

Broca’s area:

1. Where?

2. Responsible for?

3. Damage may result in?

1. inferior of left frontal lobe

2. speech production

3. Broca’s aphasia (impaired language production)

Wernicke’s area:

1. Where?

2. Responsible for?

3. Damage may result in?

1. posterior of left temporal lobe

2. language comprehension

3. Wernicke’s aphasia - impaired language comprehension

Evaluation: evidence of localisation

Petersen et al (1988) - brain scans showed Wernicke’s area = active in listening tasks + Broca’s in reading task, suggesting diff areas of the brain have diff functions

Evaluation: case study - Phineas Gage

Phineas Gage - pole through left frontal lobe - mood changed → linked frontal lobe to mood BUT low pop val/generalisation bcs case study, brain damage varies, cannot be replicated ethically

Evaluation: strict localisation is impossible

Equipotentiality principle - Lashley found no one area was more important for rats learning a maze + process of learning required every part of the cortex, suggesting localisation oversimplifies complex brain activity - no part acts independently

Evaluation: reductionist

Biologically reductionist bcs tries to reduce complex behaviours to 1 specific brain region