Exam Three - Cortex Flashcards
neurons in the cerebral cortex receive input from subcortical structure via the ____ and from other areas via ______-
thalamus
association fibers
how many layers does the neocortex have
6
how many layers does the medial temporal lobe and olfactory have
3
what is the most common type of neuron in the cerebral cortex
pyramidal cells
t or f: pyramidal cells are found in all layers
f - not layer one
in what layers are pyramidal cells most prominant
2,3,5
apical and basal dedrites are characterized by
dendritic spines
what is the primary output pathway for the cerebral cortex
pyramidal cells
gaint pyramidal cells of betz are found exclusively in the _______- and project to _________ in the lumbar SC
primary motor cortex
anterior horn
t or f: pyramidal cells are primarily glutaminergic
t
where do axons of pyramidal cells terminate (3)
1 - association cortex
2 - cross in corpus callosum
3 - project in white matter
this layer has parallel running axons
1
this layer had granule cells and pyramidal
2
this layer has smooth and spiny stellate cells and thalamocortical input
4
pyramidal cells in the _____ give rise to corticocortical projections
outer cortex
t or f: corticocortical fibers synapse in all layers
t
this layer has pyramidal cells that project everywhere
5
homotypical
evenly distributed layers
ex - occipital visual association area 19
area 19
visual association cortex
hetertypical
not even laters
ex: primary sensory cortex
primary motor cortex
area 17
primary visual cortex
area 4
primary motor cortex
area 3,1,2
primary somatosensory cortex
in this cortex layer 4 is thick while in this cortex layer five is thick
primary sensory
primary motor
what supplies blood to the cerebral cortex
ACA
PCA
MCA
anterior infarct
ACA and MCA
posterior infarct
MCA
PCA
areas 3,12 receive input from ____ and _______
VPL and VPM
area 17 receives input from
lateral geniculate nucleus
occipital and temporal lobes are reciprocally connected with the _______-
pulvinar
area 41, 42
primary auditory cortex
auditory receives input from
medial geniculate nuclei
limbic-cingulate gyrus receives info from
anterior thalamic nucleus
area 22
wernicke’s area
area 44,45
broca’s area
4 functional categories of cerebral cortex
sensory
motor
unimodal association
multimodal association
primary sensory area except olfaction receives info via
thalamocortical fibers
what is the temporal lobe involved in
audition
memory
language (geniculocalcarine radiations meyers loop)
4 clinical signs/symptoms associated with the temporal lobe
1 - kluver bucy syndrome
2 - alzheimers
3 - korsakoff syndrome
4 - wernickes aphasia
kluver - bucy syndrom
a condition, brought about by bilateral amygdala damage, that is characterized by dramatic emotional changes including reduction in fear and anxiety
examines objects by mouth
primary sensory loss
loss of tactile localization and proprioception
change in awareness of head position and movement
loss of localization of sound
homonymous hemianopsia
secondary sensory area disorders (2)
agnosia
astereognosis
agnosia
the inability to recognize familiar objects
asterognosis
inability to recognize objects by sense of touch
apraxia
impaired ability to carry out motor activities despite intact motor function
may involve premotor cortex, supplementary motor cortex, or inferior parietal lobe
2 types of apraxia
verbal and constructional
verbal apraxia
broca’s aphasia
Pt knows the word but has difficulty coordinating the muscle movement
constructional apraxia
inability to comprehend the relationship of parts to the whole (draw and arrange objects)
primary motor damage is characterized by
contralateral paresis loss of isolated movements
dysarthria
slurred speed
*primary motor cortex damage
unimodal association cortex
higher-order processing takes place mostly for a single sensory or motor modality, usually located adjacent to a primary motor or sensory area
examples of unimodal association corticeso
visual unimodal association
where is the visual unimodal association cortex and what does it do?
occipital lobe outside of 17 and inferior temporal lobe
overall perception of visual world
remaining portions of the cerebral cortex that are not motor in function are classified as
multimodal association cortex
what are multimodal association cortices critical for
language, reasoning, planning, imagination, and creativity
3 multimodal association areas
posterior association area
anterior association area
limbic association area
the cerebral hemisphere that controls language is called
dominant hemisphere
t or f: in majority of individuals the right hemisphere is dominant
f - left
what 3 lobes are responsible for comprehension and expression of language
frontal, parietal, and temporal
broca’s aphasia
condition resulting from damage to brocas area, causing the affected person to be unable to speak fluently to mispronounce words and to speak haltingly
what causes broca’s aphasia
tumor of the mca
wenickes aphasia
condition resulting from damage to wenickes area, causing the affected person to be unable to understand or produce meaningful language
what causes wernickes aphasia
MCA damage
thalamic tumors
what causes global aphasia
occluded left internal carotid artery or most proximal portion of mca
** affects both brocas and wernickes area
comparable areas of the _______ and ____ lobes on the right hemispheres contribute to prosody of language
frontal and temporal
prosody of language
variations in pitch, loudness, temp rhythm and emotions
parietal association cortex
spatial awareness and attention
where is the parietal association cortex
in the non dominant hemisphere
contralateral neglect
a disturbance of the patient’s ability to respond to visual, auditory, and somatosensory stimuli on the side of the body opposite to a site of brain damage, usually the left side of the body following damage to the right parietal lobe
dressing apraxia
ignoring left side of body when dressing
what are the 4 A’s
aphasia
apraxia
agnosia
asteognosis
what does the prefrontal cortex do?
planning, decision making, complex cognitive behavior, personality expression, social behavior
In phineas gage what was damaged
left and right prefrontal cortices ** this caused him to be highly distractible, lack foresight, ambition, responsibility, and be stubborn
what was gage verbally aggressive but not physically
because verbal aggression is from the pre-frontal cortex (which was damaged) but physical aggression is from the amygdala
what were prefrontal lobotomies used for?
calming patients with OCD, chronic anxiety, schizophrenia
cortical stroke signs
contralateral weakness and spasticity
gait and balance impairements
apraxias
hemianesthesia
cortical stroke distinguishing features
- extremities may show different degrees of involvement
- visual field deficits
- disorders of higher cortical functions
