Unit 3: skull and brain Flashcards
Brain stem
regulates autonomic functions, eye and auditory reflexes contains midbrain, pons, and medulla oblongata
reticular activating system
on/off switch for consciousness
cerebellum
large brain mass lying posterior to BS and inferior to cerebrum, coordination and modulation of complex movements
Midbrain CN
III and IV
pons CN
V, VI, VII, VIII
cerebellum effect on movement
doesnt generate any movement by itself, but fine tones everything, like eating a brownie in class, damage in cerebellum disrupts this
Medulla oblongata CN
CN IX, X, XI, XII
Dysarthria
disruption in speak
nystagmus
disruption in eye movement
Midline lesion of cerebellum
loss of postural control
distal lesion on cerebellum
effect function of arms and legs
Cerebellar lesions tends to be
ipsilateral, if on right side it will effect right arm
ventricles
protective function and clean up rubbish, supports and buffers brain against sudden movement, tightly regulated
Number of ventricles
2 lateral (cerebral hemispheres) and 2 midsaggital (diencephalon and anterior to cerebelum
choroid plexus
colored network of vessels, produces spinal fluid; leave brain behind inferior portion of cerebellum
lateral ventricle
in each hemisphere, separated by septum pellucidium
midsaggital ventricle
3rd-diencephalon, intraventricular foramen communicates with lateral ventricles; 4th inferior to cerebellum and into BS
cerebral aquiduct
runs through midbrain and communicates with 3rd and 4th ventricle, contains CSF
ependynmal cells
work in conjuction with capilaries to mak efluid
partial blindness
occipital
CSF circulation
choroid plexuses-> ventricular system-> medial&lateral aperatures-> subarachnoid space->circulation-> arachnoid granulations- dural venous sinuses
difficulty remembering words
parietal
clear fluid from nose
temporal bone let fluid escape from dura letting csf escape
unsteady gait but no sensory loss
cerebullum
nystagmus
pons, midbrain
blood supply arteries
thin walls, no vasa vasora, no int elastic lamina, thin tunica media, prone to hypertension
function of blood supply
collateral circulation route-> safegaurd against ischemia, equalize blood flow
veins of brain
no muscle no valves, do no follow arteries, open into sinuses
circle of willis
anterior cerebral, middle cerebral, posterior communicating and posterior cerebral
internal carotid
circle of willis, enters through temporal bone, courses anteriorly through cavernous sinus, forms middle cerebral arteries, supplies later side of hemisphere
middle cerebral supplies
lateral side of hemisphere
posterior cerrebral supplies
inferior part and posterior
anterior cerebral supplies
the limbic lobe, the portion just midial, between hemispheres
anterior communicating
connects two anterior branches
vertebral artery
originates from subclavian, courses through transverse foramina and foramen magnum; terminates and supplies posterior cerebral artery
types of stroke
ischemic stroke (90%, 70% effect vertebral artery); blood is very toxic to brain tissue; hemorrhagic stokes result in death (10%)
What part of the body is most likely affected in stroke?
Face, motor and sensory
weakest point of skull
frontal parietal temporal and sphenoid; pteryon: due to process of birth, it is a lap suture, easy to rupture
lies under pteryon
middle meningeal artery, receives blood from everything in skull; fracture may result in blood pushing brain medially, difficulty in speech, nystagmus etc
Cerebrum
main integration center includes hemispheres, basal ganglia
Hemispheres
highest integration functions speech, motor, emotion, memory
Basal ganglia
procedural learning of habits, moderates movement
5 lobes of cerebrum
frontal, parietal, occipital, temporal, insula
Werneke’s
if damaged causes nonsensical language
Brocas
motor control of speech
Diencephalon
central core of brain
Thalamus
relay and filter
epithalamus
links limbic system and circadian rhythms
hypothalamus
link to endocrine
