4. localisation and lateralisation Flashcards
localisation
specific areas in the brain have specific functions
brain locations acronym
most single virgins want a boyfriend
most motor cortex
single somatosensory cortex
virgins visual cortex
want wernicke’s area
a auditory cortex
boyfriend broca’s area
motor cortex
all voluntary muscle movements
in frontal lobe
in both hemispheres
somatosensory cortex
processes sensory input related to touch and produces sensations of touch pressure, pain and temperature, then localises this to specific body regions
in parietal lobe
both hemispheres, one receiving info from opposite side of body
visual cortex
vision, several different areas, process different types of visual information
in the occipital lobe
each hemisphere, receives info from opposite visual field
auditory cortex
hearing, process sound, volume, pitch, location of sound from inner ear
in temporal lobe
in each hemisphere
Wernicke’s area
language centre
Karl Wernicke, found patients with damage here couldn’t make coherent sentences or understand language
could utter words but no meaning
left temporal lobe
majority in left hemisphere
Broca’s area
Paul Broca
damage here, patients could understad language but couldn’t speak/ write their thoughts
frontal lobe
left hemisphere
brain diagram, regions and lobes
localisation, broca and wernikes areas
broca’s= damaged production of speech
wernicke’s= damaged understanding speech
lateralisation
different hemispheres different specialisations
broca’s and wernicke’s in left hemisphere
language= in left
Wernicke’s Aphasia
can’t understand speech/ formulate coherent sentences
utter words, sentence have no meaning
Broca’s Aphasisa
can’t articulate speech fluently
language= disjointed
writting disruptd
understanding of language= near normal
how do Broca’s and Wernicke’s areas interact to produce language
Wernicke’s (analyses sound) near the cortex that analyses sound and understanding speech
Broca’s (articulating speech)close to motor region controls movement,
sensory region of brain= auditory/visual input
transferred by audio/visual cortex
wernicke’s area= regognised as language, associated with meaning
broca’s area= speech needs to be produced is identified
transferred via motor cortex to
produce speech
evaluation of localisation of function
strength
supportive research
Petersen et al
Petersen et al 1988,
brain scans show Wernicke’s area active in listening task and Broca’s for reasoning
localisation= certain areas for different tasks
evaluation of localisation of function
strength
practical applications
people suffered from strokes, syptoms like speech impairment suggest affected areas
treating sympotoms, gradual re-training needed
helpful for recovery
evaluation of localisation of function
limitation
danelli et al
boy
boy had most left hemisphere removed due to tumor at 2 and linguistic ability ended
under rehab by 17 compared to ‘normal’ language, right hemisphere compensated for left
questions localisation showing brain plasticity
evaluation of localisation of function
limitation
case studies
evidence based on case studdies
each brain damage is very specific to the person so the exact damage won’t be the same and not generalisable to other non-damaged brains.
can’t say localisation happens in ‘normally’ functioning brains
brain lateralisation
2 hemisphers aren’t the same
left for language
conected by corpus callosum to communicate
sperry
split brain research
PROCEDURE
participants with same surgical procedure to treat epilepsy, cut corpus callosum down the middle
focused on dot
info presented in a left or right visual field is sent to opposite hemisphre
responded with hand controlled by opposite hemisphere and verbally
compared to control group
sperry
split brain research
VARIATION
describe what’s been seen:
words in righyht VF reported
unaware of words in left VF
because left hemisphere deals with language
recognition by touch:
left hand behind screen with objects
word flashed to right hemisphere
left hand can select the same object
right hemisphere recognises basic nouns
patient can’t explain, no lanuage
matching faces:
picture prossesed in right hemisphere selected correctly
left hemisphere ignored
in both VF left hemisphere dominated in verbal description and right in mstching picture
right hemisphere dominant in recognising faces
sperry
split brain research
EVALUATION
limitation
population validity
low population validity
11 males
differences in opperations, some had smaller pathways not part of corpus callosum connecting hemispheres cut too
can’t develop a model of hemisphere lateralisation using only split brain research
sperry
split brain research
EVALUATION
limitation
counter evidence
says right hemisphere can’t handle language
turk et al reported JW developed ability to speek from right hemisphere
shows brain plasticity
