Chapter 10: Cerebral Cortex Flashcards
What layer of the neocortex is the terminationn of the thalamocortical projections?
internal granular layer?
What are the 6 layers of the neocortex?
I. molecular
II. external granular
III. External pyramidal layer
IV. Internal granular layer
V. Internal pyramidal layer
VI. Multiform layer (layer of polymorphic cells)
Which layer of the neocortex give rise to the corticospinal and corticobulbar tracts?
multiform layer
What areas of the brain are supplied by the middle cerebral artery (MCA) supplies? (in general)
- lateral surface of the frontal, parietal, and upper temporal lobes
- posterior limb and genu of the internal capsule
- most of the basal ganglia
Left sided middle cerebral artery occlusion can lead to what condition specific conditions?
Broca or Wernicke aphasia
Right sided middle cerebral artery occlusion?
left sided neglect
Occlusion of branches of the middle cerebral artery that supply Meyer’s loop fibers in the temporal lobe result in what condition?
contralateral superior quadrantanopsia
What structures does the ACA supply?
medial surface of the frontal and parietal lobes; anterior 4/5 of corpus callosum; anterior limb of internal capsule
What areas of the brain does the PCA supply?
supplies occipital lobe; lower temporal lob; splenium; midbrain
What is the most common site for an aneurysm?
where the anterior communicating artery joins an anterior cerebral artery
How do thrombotic cerebral infarcts appear?
anemic/ pale infarct; usually atherosclerotic complication
How do embolic cerebral infarcts appear?
hemorrhagic/ red infarct; from heart or atheroscelrotic plaques middle cerebral artery most vulnerable to emboli
how do hypotension cerebral infarcts appear?
“watershed” areas and deep cortical layers most affected
How do infarcts caused by hypertension appear?
lacunar infarcts; basal ganglia, internal capsule, and pones most affected
Cause of epidural hematoma
rupture of middle meningeal artery after skull fracture
almost always traumatic
Characteristics of an epidural hematoma?
lucid interval before loss of consciousness (“talk and die” syndrome)
What is the cause of a subdural hematoma?
- usually caused by trauma
- rupture of bridging veins (drain brain to dural venous sinuses)
What is the cause of subarachnoid hemorrhage?
ruptured berry aneurysm most commn cause
Predisposing factors of subarachnoid hemorrhage?
Marfan syndrome, Ehlers-Danlos type 4, adult polyscystic kidney disease, hypertension smoking