Localistation Of Function Flashcards
Whta is localisation
Some major brain functions are located in specific areas of the cerebral cortex
Bilateral
Represented symmetrically in each hemisphere
4 primary bilateral areas
- primary motor cortex
- primary visual cortex
- primary auditory cortex
- primary somatosensory cortex
What areas are lateralised
- brocas area
- wernickes area
Lateralised
Only appear in on hemisphere
Primary motor cortex
- volunteers motor function (movement)
- highly localised in frontal lobe of brain
- on one side of brain controls muscles on the opposite side of the body
- found in both hemispheres
Primary somatosensory cortex
- detects sensory event (touch, pain)
- highly localised in parietal lob of te brain
- both hemispheres
- cortex on one side of the brain receives sensory info from opposite side of the body
Primary visual cortex
- processes and interprets visual information received by the eyes
- localised in occipital lob of the brain
- both hemispheres
- right hemisphere receiving input from left and side of visual field and visa versa
- contains several different areas, each area processing different types of visual info eg colour,shape
Primary auditory cortex
- hearing
- localised temporal lobe
- revives info from both ears, auditory info from right ear mainly goes to left hemisphere however some is transmitted to the right primary auditory cortex
- enables perception of the location of a sound
Contralateral
Right hemisphere deal with left handed info or visa versa
-opposite side
Ipsilateral
Same side
Broca’s area
- motor control of speech production
- one hemisphere
- left frontal lobe
What occurs if Barca’s area is damaged
- brocas aphasia
- eg stuttering assoitated with under activity in Broca’s area
- ‘ no what they want to ay but cant get it out’
Wernickes area
- language comprehension, accessing stored words in order to interpret language
- left temporal lobe
What occurs when wernickes area is damaged
- wernickes aphasia
- struggle to make sense of what they read or hear and also finding correct word when speaking or writing language
- often speak fluently while talking nonsense as they are using the wrong words
Supporting evidence
- case study
- phone as gage
- accident where a iron rod blasted through his frontal lobe
- after the accident change in his personality
- suggest frontal lobe is in charge of mood regulation
Evidence against location of brain
- lashely
- removed area of cortex in rats that were learning a maze and found that this had no effect of progress
- suggest more complex cognitive functions the whole brain is involved
Weakness
- plasticity provides an gru ent against localisation
- brocas noted that brain unction wasn’t fixed as most aphasias regained some of their abilities
- suggested right hemisphere was taking over some functions of the left
- the brain can learn new ways of functioning following damage therefore functions are not rigidly localised
- gender differences Found within research
- harasty et al found women have large Broca’s and wernickes areas then men
- difference makes it difficult to map specific areas
Location of primary motor cortex
Frontal lobe
Location of primary visual cortex
Occipital lobe
Location of primary auditory cortex
Temporal lobe
Location of somosensory lobe
Parietal lobe
Location of broca area
Left frontal lobe
Location of wernickes area
Left temporal lobe
