localisation of function Flashcards
1
Q
localisation of function
A
- refers to the principle that functions have specific locations in the brain
- some functions are more localised than others
- motor + somatosensory functions = highly localised to specific areas
- language system = widely distributed (uses several parts of brain)
- HOWEVER some components e.g. speech production may be localised (Broca’s Area)
2
Q
visual + auditory centres
A
- visual centres
- auditory centres
3
Q
visual centres
A
- visual cortex processes info e.g. colour + shape
- located in OCCIPITAL LOBE in BOTH hemispheres
- visual process starts in retina
- light enters + strikes photoreceptors
- nerve impulses from the retina are transmitted to the brain
- via the optic nerve
- majority terminate in the thalamus
- passing info onto the visual cortex
4
Q
auditory centres
A
- auditory cortex processes info e.g. pitch + volume
- located in the TEMPORAL LOBE in BOTH hemispheres
- auditory pathway begins in the cochlea (in inner ear)
- sound waves converted to nerve impulses
- travel via the auditory nerve
- to the auditory cortex
- basic decoding in the brain stem
- thalamus carries out further processing before impulse reaches the auditory cortex
5
Q
Motor + Somatosensory Areas
A
- the motor cortex
- the somatosensory cortex
6
Q
the motor cortex
A
- located in FRONTAL LOBE of BOTH hemispheres
- responsible for voluntary movements
- damage to this area = loss of muscle function/ paralysis in one or both sides of the body
7
Q
the somatosensory cortex
A
- responsible for processing sensations
- e.g. pain + pressure
- located in PARIETAL LOBE of BOTH hemispheres
8
Q
language centres
A
- Broca’s Area
- Wernicke’s Area
9
Q
Broca’s Area
A
- located in the LEFT HEMISPHERE
- in FRONTAL LOBE
- damage to this area = expressive aphasia
= affects language production
= speech lacks fluency
10
Q
Wernicke’s Area
A
- located in the LEFT HEMISPHERE
- in TEMPORAL LOBE
- connected to the Broca’s Area by a neural loop
- damage to this area = receptive aphasia
= impaired ability to understand language
11
Q
disads of localisation of function
A
- localisation
- language
- areas communicate
- individual differences
- equipoteniality theory
12
Q
localisation - disads
A
- some functions are more localised than others
- motor + somatosensory functions are highly localised to specific areas in the cortex
- HOWEVER, higher functions (e.g. personality) are much more widely distributed
- functions e.g. language etc.. are too complex to be assigned to one area
= instead involve networks of brain regions
13
Q
language - disads
A
- psych re-examined the preserved brains of two Broca’s patients
- MRI scans revealed that several areas of the brain had been damaged
- lesions to the Broca’s Area cause temporary speech disruption
- they don’t usually result in severe disruption of language
= language is a more widely distributed + less localised skill than originally thought
14
Q
areas communicate - disads
A
- may be that how brain areas communicate w/ each other is more important than specific brain regions
- psych reported a patinet who couldn’t read
- cus of damage between the visual cortex + Wernicke’s Area
15
Q
individual differences - disads
A
- psych found that there are individual differences in which brain areas are responsible for certain functions
- found that different brain areas are activated when a person is engaged in silent reading
- observed activity in the right temporal lobe, left temporal lobe + occipital lobe
= means that the function of silent reading doesn’t have a specific location in the brain
