Gross Brain, Meninges and Sinuses Flashcards
How does the brain stimulate movement? Maintain homeostasis?
- sensory and motor inputs
- between internal and external environment
What functional modality is served in occipital lobe?
vision, contains primary visual cortex
What functional modality is served in parietal lobe?
sensation and information integration (contains primary sensory cortex)
What functional modality is served in temporal lobe?
motion (contains primary motor cortex)
What contains fibers connecting cerebral hemispheres?
corpus callosum
What is the relay station for all senses? Which sense is missing?
Thalamus, olfaction
Where is the center for autonomic and endocrine functions?
hypothalamus
What is the “master” gland for homeostasis?
pituitary gland
Where is the center for sleep-wake cycles?
pineal gland
Where are the nuclei related to emotions? (ant to midbrain)
mammillary bodies
What are the 2 main sources of blood to brain?
ICA system and vertebrobasilar arterial system
What is the anastomoses between the 2 main sources of blood to the brain?
circle of willis
Path of ICA
carotid canal -> 90˚ turn -> ascends sup foramen lacer -> enters cavernous sinus into cranial cavity
Vertebral a path
transverse foramina of C6 and above -> 90˚ turn -> foramen magnum -> joins opposite vertebral a and forms basilar a
What does ICA terminate as?
middle and anterior cerebral aa
What does the vertebrobasilar system supply?
posterior brain
What do the posterior spinal aa supply?
post 1/3 spinal cord
What do ant spinal aa supply?
ant 2/3 spinal cord
What does post inf cerebellar aa supply?
inf cerebellum and lateral medulla
What brain lobes do the ant cranial fossa hold? bones?
frontal lobes
- frontal, ethmoid, sphenoid
What brain lobes do middle cranial fossa hold? bones?
temporal lobes
- sphenoid, parietal, petrous portion of temporal
What lobes do post cranial fossa hold? bones?
cerebellum and brainstem
- temporal, parietal, occipital
Where does middle cranial fossa extend?
lesser wing of sphenoid bone to sup extent of petrous portion of temporal
What is the rough outer layer of dura mater adherent to the skull?
periosteal layer
What is the smooth inner layer of dura mater that covers arachnoid mater?
meningeal layer
What occurs when middle meningeal a tears quickly?
leads to epidural (extradural) hematoma (arterial bleeding between dura mater and skull)
Fractures in which portion of the skull commonly produce tearing of ant branch of middle meningeal a (frontal br)?
pterion
T/F the brain has sensory innervation
F, the meninges do
Where is falx cerebri found between?
sagittal fissure
Where is falx cerebelli found between?
two cerebellar hemisphere
Where is tentorium cerebelli found?
between cerebrum and cerebellum
Where is diaphragma sellae found?
between brain and pituitary gland
What passes through cavernous sinus?
ICA and CN VI
What CNs are sheathed in the lateral wall of cavernous sinus?
CN III, IV, V1 and V2
What results from ICA rupture with skull base fractures?
arteriovenous fistula -> abnormal reflex of blood into ophthalmic vv (pulsating exophthalmos)
What occurs with. blows that jerk the brain inside the skull?
subdural hematoma, rupture of cerebral v. limited by falx cerebri and tentorum cerebelli
What is the thin non-vascular membrane loosely surrounding the brain?
arachnoid mater
What is deep to the arachnoid mater?
arachnoid space
Where are cerebral and cerebellar blood vessels found?
in subarachnoid space, contains CSF
What acts as shock absorber forming fluid cushion of gyri and sulci?
subarachnoid space
What is the delicate membrane surrounding the brain and is pierced by vessels supplying the brain?
pia mater
