Neuro Cortex Flashcards
What is the predominant cell type of the cerebral cortex?
pyramidal cell
What are the layers of the cerebral cortex and how many layers does each contain?
1) Neocortex (6 cell layers) 2) Archicortex (3 cell layers, includes hippocampus)
What do thalamocortical fibers do?
They connect the thalamus to the cortex
What do association fibers do?
they connect one region of the cortex to the other on the same side
What do commisural fibers do?
They connect one side to the same region on the opposite side
What 4 areas do projection fibers go to?
1) basal ganglia 2) limbic system 3) brainstem 4) spinal cord
What is the name of the tract that contributes to visual projections?
geniculocalcarine tract (optic radiations). This tract starts in the lateral geniculate nucleus of the thalamus thru the upper and lower divisions to the visual cortex (striate cortex) along the calcarine fissure
The cerebral cortex is anatomically divided into _____ layers but is functionally divided into vertical columns. This is recognized in the visual cortex
2 (neocortex & archicortex)
The vertical columns of the cortex are about what size dimensionally?
1mm^2. Note that columns alternate for projections from each eye
What number Brodmann’s area is the primary visual cortex?
17 (retinotopic visual field representation, detection of edges/fill-in-the-blank)
What number Brodmann’s areas are the visual association cortex?
18 & 19 (color and stereopsis)
Parallel processing involves the parvocellular & magnocellular systems. What does each to?
1) parvocellular (detail & color)
2) magnocellular (location & movement)
Where does the magnocellular system project to?
superior parietal lobe
Where does the parvocellular system project to?
inferior temporal lobe
Which artery supplies the visual cortex?
posterior cerebral artery
What is the effect of a lesion of the visual association cortex?
visual agnosia (not knowing)
Damage to the fusiform face area is associated with what disorder?
autism
The superior parietal lobule contains which Brodmann areas?
5 & 7
What two gyri are within the inferior parietal lobule?
supramarginal gyrus and angular gyrus
What is the effect of a lesion of the parietal cortex?
loss of sensation over contralateral body
What is the overall function of the partietal lobe?
knowing where everything is located and creates plans to contact objects on and near body
Brodmanns areas 5 & 7 are of the superior parietal lobe and are also known as what?
somesthetic association cortex
What two senses input to the superior parietal lobule?
touch and vision (object location, size, shape, orientation)
What is the physical function of the superior parietal lobule?
eye and arm movement (intraparietal sulcus)
What is the output of the superior parietal lobule?
ipsilateral motor cortex?
What is the effect of a lesion of the superior parietal lobule?
tactile agnosia and optic ataxia
What two brodmann’s areas make up the inferior parietal lobule?
40 & 39
What artery supplies the inferior parietal lobule?
middle cerebral artery
What is the input to the inferior parietal lobule?
touch and especially vision
What is the role of the inferior parietal lobule?
it maps velocity and direction of visual objects
What is the effect of a lesion of the inferior parietal lobule?
inability to carry out learned motor acts (apraxia) as well as Gerstmann’s syndrome which includes finger agnosia, a difficulty in reading and writing as well as left-right confusion
What is sensory hemineglect syndrome?
it is a lesion of the non-dominant inferior parietal lobule resulting in a loss of map of a contralateral body and world as well as unawareness of the disorder (anosognosia)
What Brodmann’s area is in the temporal lobe?
area 41, L temporal lobe is specialized for speech, R temporal lobe is for music. Medial temporal lobe is for memory: lesion = amnesia
Speech and language are a function of the ____ hemisphere
dominant
Language is assembled & interpreted in what area
Wernike’s area
What BA is Wernike’s area?
22 (posterior superior temporal gyrus)
What artery serves Wernike’s area?
middle cerebral artery
What is the effect of a lesion to Wernike’s area?
free-flowing speech with no content
What BA is the primary motor area of the frontal lobe? How about premotor?
primary motor cortex = 4, premotor = 6, served by MCA
What is the effect of a lesion to the primary motor cortex?
contralateral paralysis of leg
What is the effect of a lesion to the supplementary motor cortex?
akinesis, dominant-side mutism (no speech)
Where does the prefrontal cortex get input from?
parietal and temporal cortex, it interacts with the orbitofrontal cortex
What is the job of the prefrontal cortex?
working memory… planning motor responses (in space and time)
Where does the orbitofrontal cortex connect?
limbic system, hypothalamus (where emotions are appreciated)
repository of socially acceptable behavior
Broca’s area deals with speech and language in dominant hemisphere… which Broadmann’s area, which artery, result of lesion?
areas 44 and 45, MCA, lesion = broca’s expressive aphasia (jerky, halting speech with no content)
