Internal Anatomy Flashcards
What is the Basal Ganglia?
subcortical nuclei; caudate, putamen, and globus pallidus (substantia nigra and subthalmic nucleus are also part of it but less commonly mentioned)
What is the striatum?
The caudate nucleus + putamen n.
What is the most common cause of destruction of the BBB?
Ischemia. Brain tumors and bacterial invasion can have the same result but are much less common.
What is the primary secreter of CSF? How much does it produce per day?
The choroid plexus. It produces ~500mL per day. typically there is 140mL of CSF and thus it turns over 3-4 times a day.
What produces obstructive or non-communicating hydrocephalus?
An obstruction at the cerebral aqueduct. This is often caused by a tumor.
What is communicating hydrocephalus?
When there is no blockage of ventricular flow, but the arachnoid villi are diseased and absorption fails.
What is papilledema? When does it happen?
When the retinal vessels of the optic nerve become engorged and the optic nerve head becomes dilated. This happens in hydrocephaly, or more generally when there is increased intracranial pressure.
The deep white matter of the cerebrum is classified into three categories: association, commissural, and projection fibers, what do each of them do?
Association - connect different areas of cortex in the same hemisphere (2 way signaling).
Commissural - connect homologous areas of cortex of the two hemispheres.
Projection - connect areas of cortex to lower areas of the neuraxis.
The superior longitudinal fasciculus (arcuate faciculus) is the largest association fiber, it connects what structures?
It connects the frontal, occipital, and temporal lobes. Broca’s motor speech area, Wernicke’s area and the auditory cortex.
The inferior longitudinal fasciculus connects what structures? (association fiber)
The occipital lobe to the temporal lobe
The uncinate fascicles connects which structures? (association fiber)
Connects the frontal and temporal lobes
The cingulum connects what structures? (association fiber)
Interconnects structures of the limbic system: subcallosal gyrus, cingulate gyrus, parahippocampal gyrus and uncut.
The largest of the commmissural fiber tracts is the corpus collosum, what does it connect?
Homologous areas of cortex between the two hemispheres. The frontal lobes throughout he genu, parietal via the body, and occipital via the splenium facilitating binocular vision.
What does the anterior commissure connect?
The anterior poles of the two temporal lobes containing the primary olfactory cortices.
What does the hippocampal commissure connect?
It is axons of the fornix that cross where the two fornices approach on another.
