Cortex Localization Flashcards
how did brodmann define his original areas?
slight differences in the cellular composition and laminar structure w/in the cortex
executive v perceptual corticies
frontal- executive
caudal- perceptual
association cortex
input from multiple sensory modalities
associated w/ higher processes such as memory, planning, language, math
parietal association cortex
includes brodmann area 7
involved w/ spatial localization , attention, agency
important for working memory w/ frontal
deficits can result in neglect- contralateral neglect occurs when damage occurs in non dominant hemisphere
deficits also cause optic apraxia, optic ataxia, and tactile agnosia
contralateral neglect syndrome
caused by damage to non dominant parietal cortex
non dominant parietal lobe attends to both sides of world
spatial attention in dominant hemisphere is only contralateral, thus loss of non dominant parietal cortex leads to contralateral neglect
deficits may be severe or very mild (extinction)
optic apraxia/ataxia
apraxia- deficits in visual scanning of the environments
ataxia- deficit in hand eye coordination
both caused by parietal damage
balints syndrome
co occurrences of optic apraxia, ataxia, and simultanagnosia (inability to perceive multiple objects in visual field
occurs following bilateral parietal damage
tactile agnosia
inability to identify objects by touch despite normal sensory ability
requires parietal cortex
temporal association cortex
brodmanns areas 21 and 22
process auditory and visual info, important for object recognition and language comprehension
deficits: visual agnosia, prosoagnosia, auditory agnosia, receptive aphasia, acalculia
visual agnosia
inability to recognize objects by sight
temporal association
prosopagnosia
inability to recognize faces
occurs after lesions to non dominant inferior temporal lobe
auditory agnosia
inability to recognize or make sense of complex sounds (words)
temporal association
receptive aphasia
wernickes aphasia
damage to wernickes area leads to deficits in language comprehension
temporal association
acalculia
impairs ability to do math
occurs w/ damage to dominant temporal lobe and angular gyrus
dorsolateral cortex
areas 9 10 46
executive functions- working memory, judgement, planning, sequencing of activity, dividing attention, abstract reasoning
orbitomedial prefrontal cortex
areas 11 and 12
impulse control, personality, reactivity to surroundings, mood
anterior cingulate gyrus
part of orbitomedial prefrontal cortex
associated w/ mood
frontal cortex and motor behaviors
frontal cortex inhibits motor behaviors, but this can be impaired if the frontal cortex is damaged
ex. utilization behaviors- individuals grasp nearby objects in meaningful ways but at inappropriate times
perseveration- repetition of a normal motor pattern after it should stop
vountary movement
associated w/ a sense of agency that stems from parietal cortex
however, the decisions themselves are associated w/ increased activity in supplementary motor cortex before their is conscious awareness of the decision- readiness potential
abulia
inability to initate movements
alien hand syndrome
damage to the connections between frontal and parietal association cortex
there is no sense of agency,
and the hand seems to move as it it were independently controlled
dominant v non dominant hemispheres
applies to which hemisphere shows language specialization
most people- left is dominant and has language
Wada test
anesthetic injected into internal carotid only on one side while they are doing a task that requires verbal skills- identifies langauge dominant hemisphere
language cortex
wenickes (22) and brocas (44 and 45- inferior frontal gyrus) areas
wernickes- receptive aphasia- problems decoding the meaning of words
brocas- motor aphasia- difficulty generating spoken or written words
both are also used for abstract symbolism- both used in deaf individuals for sign language
transcortical aphasias
wernickes and brocas are intact, but areas around them are damaged
repeat very well, but cannot understand complex phrases or generate spontaneous language
echolalia- parrot back whatever is said to them
non dominant wernickes and brocas areas
used to understand or generate inflections that put language into context
self identification v identification of others
self ident- occurs in dominant hemi
others- occurs in non dom- including facial recognition
prefrontal laterlization
damage to dominant produces depression
damage to non dom produces mania
