Flashcards in Neuroanatomy Deck (125)
What are ascending tracts?
Sensory info from peripheral nerves is transmitted to the cerebral cortex. Also called somatosensory pathways.
Two types of ascending tracts?
Conscious: Dorsal column lemniscal and anteriolateral
Unconscious: spinocerebellar tracts
How are the two cerebral hemispheres connected?
Via the corpus collosum,
What are the ventricles? Route the CSF takes?
The lateral ventricle, with inferior, Anterior, Dorsal and Posterior horn.
Through the interventricular foramen (or foramen of monroe), to the third ventricle.
Down the aquaduct to the forth ventricle.
Down the central canal to spinal cord.
What is the function of the CSF?
1. Buoyancy- reduces the weight of the brain from 1.4kg (male) or 1.2kg female to 25g.
2. Protection- cushions from physical damage
3. Chemical homeostasis- keeps exc K+ low
Where is CSF produced?
Ependymal cells in Choroid plexus found in all the ventricles
How is the CSF recycled?
500ml made but only 150ml present.
reabsorbed through arachnoid granulations into the superior sagittal sinus to venous circulation.
Where is the third ventricle? e.g. structures near
Either side of the third ventricle is the thalamus, connected by the interthalamic adhesion.
Where is the forth ventricle? e.g. structures near
located in the brainstem, between the pons and the medulla oblongata, cerebellum posterior to
What is the Diaphragma sellae?
Flat piece of dura mater that roofs the pituitary gland (held in the hypophyseous fossa or sellae turcica of sphenoid)
What spaces surround the dura mater in the spinal canal?
Extradural space above the dura mater
Subdural space below the dura mater
What space is there in both the spinal canal and brain meninges?
Subarachnoid space below the arachnoid (so above the pia)
If the lateral sulcus is pulled apart what can be seen?
What are the layers brain to scalp?
Brain, Pia, arachnoid, dura (meningeal then endosteal), skull, periosteum, epicranial aponeurosis, scalp.
Area where neurons enter the thalamus?
fornix (from the hippocampus to hypothalamus)
Anterior to posterior areas of the corpus collosum?
Rostrum, Genu, body, Splenium
What separates the anterior horns of ventricles?
Where is the parietal-occipital sulcus?
separating the parietal and occipital lobes.
Where is the lateral aperture located? Median?
The forth ventricle from posterior makes a diamond shape, the two lateral points are named the lateral aperture.
The median is the inferior point where it converges onto the central canal.
Where is the brains longitudinal fissure?
in midsagittal plane, splits the two hemispheres in two.
Where is the brains lateral fissure/ sulcus?
Separates the temporal lobe from parietal and frontal. (if pull apart can see insula)
Function of insula?
Wheres the central sulcus?
Coronal cross section splitting the frontal lobe from the parietal. Before this sulcus is the precentral gyrus, and posterior to is the postcentral gyrus
The cerebellum derives from which developemental structure?
The cerebellum lies at the same level just posterior to what structure?
the pons, separated by the forth ventricle.
The two cerebellum hemispheres are connected by?
Distribution of white and grey matter in the brain, cerebellum and spinal cord?
Brain and cerebellum grey is on surface and white in centre, but for the spinal cord this is the opposite so grey butterfly structure surrounded by the white matter.
What are the three cerebellal lobes?
anterior, posterior(or middle) and flocculonodular
What fissures divide the cerebellal lobes?
Primary fissure between anterior and posterior
Posterolateral between the flocculonodular and posterior