General features of the brain & meninges Flashcards
What are the names of the 4 bones that form the upper vault of the skull?
Frontal
Parietal
Temporal
Occipital
What are the gyri?
Rolls of the cerebral cortex
What are the sulci?
Grooves between the gyri
What is the central sulcus and what does it separate?
Its a large fissure that separates the frontal lobe from the parietal lobe
What is the longitudinal fissure?
Its the midline that separates the right and left hemisphere
What is the lateral fissure and what does it seperate?
Its a large fissure that separates the temporal lobe from the frontal and parietal lobe
What is the corpus collasum?
Its a large bundle of white matter that connects the 2 hemispheres
Where does the olfactory tracts lie on the underside of the brain?
They run along the surfce of the lobes
seen anteriorly
Where does the optic nerves pass?
They pass backwards and medially
When the optic nerve converge what do they form?
The optic chiasma
What passes laterally and backwards to the optic chiasma?
The optic tracts
How do the optic tracts pass?
Pass laterally and backwards to the optic chiasma
What are the mamillary bodies and where do they lie?
2 round eminences located behind the optic chiasma
Where does the hypothalamus lie and what does it include?
behind the optic chiasma and includes the mammillary bodies
Which part of the hypothalamus is most visible when looking at the underside of the brain?
Diencephalon
When When tumours form on the pituitary gland what structure can they apply pressure on? what structure can they apply pressure on?
The optic chiasma
what are the clinical consequences of pressure applied on the optic chiasma due to tumours formed on the pituitary gland?
Bilateral hemianopia which is the loss of peripheral vision
What are the crura cerebri and the cerebral peduncles?
2 large masses of white matter emerging on either side of the mamillairy bodies
How do the crura cerebri and the cerebral peduncles lie?
They pass backwards and converge in the midline at the upper border of the pons
What is the interpenduncular fossa?
Space between the crura roofed over by the arachnoid
Where is the pons situated?
immediately behind the point where crura meet in the midline
What does the pons form?
It forms a bridge of neural tissue between the midbrain and medulla oblongata
What can the cerebellum also be referred to as?
The little brain
Describe the structure of the Cerebellum?
It has 2 lobes on either side of the medulla and a central vermis joining the 2 hemispheres
What are the 3 structures that make up the brain stem?
Midbrain
pons
medulla oblongata
What are the 4 cranial nerves that are given off the medulla oblongata?
Glossopharangeal (CN IX)
vagus CN X
Hypoglossal CN XII
Accessory CN XI
What 2 centres are housed in the medulla oblongata
Cardio and respiratory centres
What does the medulla oblongata lie close to?
Foramen magnum
What is the function of the parietal lobe?
Perception and interpretation of sensory information
formation of motors responces
What are the 8 functions of the frontal lobe?
motor function problem solving memory language judgement personality social behaviour sexual behaviour
Which lobe is the Broca area a part of?
Frontal lobe
Where can the broca area be found in the frontal lobe?
Found at the inferior frontal gyrus
What is the Broca area important for?
Language production and comprehension
What is the hippocampus involved in?
long term memory formation
What is the amygdala involved in?
Reward and fear responses
What does amygdala influences in order for it exert its effects?
ANS and the endocrine system
Which part of the brain/limbic system is highly connected to pleasure centres in the brain?
The amygdala
What are the 3 meningeal layers of the brain?
Dura
Arachnoid
Pia
How many layers make up the dura?
2 layers
What are the names of the 2 layers that make up the dura mater?
Outer endosteal layer
Inner meningeal layer
What is the name of the outer layer of the dura mater?
The outer endosteal layer
What is the name of the inner layer of the dura mater?
The inner meningeal layer
What does the outer endosteal layer of the dura line?
Lines the interior of the skull
What does the outer endosteal layer of the dura send to the cranial bones?
Blood vessels and fibrosis processes
Where do blood vessels and fibrosis processes of the endosteal layer of the dura get sent to?
To the cranial bones
What does the inner meningeal layer of the dura cover?
completely envelopes the CNS
Which layer of the dura mater continues as a tube and is seen around the spinal cord?
The inner meningeal layer
What does the inner meningeal layer of the dura cover do for the cranial nerves?
Provides tubular sheaths for the cranial nerves
What are the Dural venous sinuses?
It is a system of communicating blood filled spaces where the dural folds attach to the skull
Which sinus in the brain is the most clinically important?
Cavernous sinus
True/False:
The outer endosteal layer and inner meningeal later of the dura mater fuse for the most part?
True
What do the dural folds support?
The subdivisions of the brain
Where is the Falx cerebri located?
In the longitudinal fissure
Where is the superior sagittal sinus located?
Where the falx cerebri attaches to the cranium
What is the tentorium cerebelli and what does it form a roof over?
Dura forming a thick fibroud roof over the posterior cranial fossa and the cerebellum
What is the flax cerebelli?
Small vertical sickle shaped reflection of dura separating the 2 lobes of the cerebellum
What is the name of the mater that encloses the brain loosely following the dura?
Arachnoid mater
What is the name of the space that exists between the arachnoid and pia mater?
Subarachnoid cisterns
What is the subarchnoid cisterns filled with?
CSF
Where is the straight sinus located?
Within the tentorium cerebelli and attaches to the flax cerebri
What is the name of the layer that is closely adherent to the underlying nervous tissue of the brain?
Pia mater
What is the name of the meningeal layer that forms part of the BBB?
Pia mater
Why is the pia mater functionally very important?
Forms part of the BBB
