Gross Anatomy of Brain and Spinal Cord Part 2 Flashcards
what marks the location of the visual cortex
calcarine sulcus
what are the parts of the corpus callosum
genu, body, splenium and rostrum
what are the coronal radiata
fibres running to and from the cortex and thalamus beneath the grey matter (run through internal capsule)
what are the parts of the internal capsule
anterior limb, posterior limb and genu
where does the anterior limb of the internal capsule run
between head of caudate nucleus and lentiform nucleus
where does the posterior limb of the internal capsule run
between lentiform nucleus and thalamus
what does the lentiform nucleus consist of
putamen and globus pallidus
why is the internal capsule vulnerable for stroke
because it is supplied by narrow arteries and which are easily blocked and it also has lots of nerves running through it which will have a devastating effect on the other side of body
where does the corticospinal tract run
passes through the lateral aspect of the posterior limb all the way through the CNS
what does the corticospinal tract mediate
voluntary movement across the body
what are the 5 basal nuclei
caudate nucleus, globus pallidus, putamen , subthalamic nucleus, substantia nigra
what is the corpus striatum made up of
caudate nucleus and putamen + globus pallidus
what is nuclei
grey matter connected to the thalamus, cortex and neighbouring nuclei
what do the nuclei do
project neurons to the thalamus with the thalamus acting as a relay for information to the cerebral cortex
what does damage to the basal nuclei result in
loss of control of movements (parkinsons/huntingtons)
what does the hypothalamus do
maintains homeostasis, monitors internal environment, controls release of hormones from pituitary gland
how does the hypothalamus control the release of hormones from pituitary gland
through releasing hormones
where does the pituitary gland sit
in the sellae turcica in the middle cranial fossa
what connects the pituitary gland and hypothalamus
pituitary stalk
what is the function of the pituitary gland
regulates hormone release through releasing or inhibiting hormones
what hormones does the pituitary gland release
growth hormone, thyroid stimulating hormone, follicle stimulating hormone
what is acromegaly caused by
overproduction of growth hormone by pituitary gland (pituitary tumour)
what do the symptoms of acromegaly include
growth of hands and feet, voice deeper, lips nose and tongue larger
if acromegaly is left untreated what can it lead to
high blood pressure, diabetes, sleep apnoea
what are ventricles
fluid filled cavities within the brain that provide protection to the brain
what do the ventricles produce
CSF
what part of the ventricles produces CSF
choroidal epithelial cells of choroid plexus
what are the different ventricles
lateral, 3rd, 4th
what are the lateral ventricles separated by
septum pellucidum
what connects the lateral ventricles to the 3rd ventricle
interventricular foramen
what connects the 3rd and 4th ventricles
cerebral aqueduct
what does the CSF leave the 4th ventricle by
lateral / median apertures
what happens if there is a blockage in the lateral and median apertures in the ventricular system
blockage, accumulation of CSF, distension of ventricles and compression of cerebral hemispheres
how does the CSF protect the brain
by providing a cushion and buffer against blows to the head. provides buoyance in subarachnoid spaces preventing the brain from crushing the cranial nerve roots and blood vessels
where does the CSF go after being circulated through the subarachnoid space
reabsorbed into the venous system through arachnoid villi and granulations
what is the decussation of pyramids
structure in nervous system (brainstem) where fibres cross to the opposite side
where does the spinal cord begin
at foramen magnum of skull as continuation of medulla
where does the spinal cord end
L1/L2 vertebrae
what is the inferior end of the spinal cord known as
conus medullaris
what does the conus medullaris continue as at the end of the spinal cord
filum terminale
what does the filum terminale do
anchor spinal cord to coccyx
what are the 2 enlargements in the spinal cord
cervical and lumbosacral enlargements
where is the cervical enlargement and what does it supply
C4-T1 - upper limbs
where is the lumbosacral enlargement and what does it supply
T1-S1 - lower limbs
what do the ventral horns innervate
efferent motor
what do the dorsal horns innervate
afferent sensory
what is the canal in the middle of the spinal horns filled by
CSF
what do the ventral and dorsal nerves converge to become
spinal nerve
where do the spinal nerves emerge from
adjacent vertebrae (except C1)
where does c1 spinal nerve emerge from
between occipital bone of skull and C1 atlas
what is the spinal cord protected by
meninges
what does the spinal epidural space do
separate the spinal dura from the bony canal
what are the layers protecting the spinal cord
pia mater, arachnoid mater, dura mater, epidural fat
what is a myotome
anatomically and functionally related group of skeletal muscle innervated by a single nerve
what is a dermatome
localised area of skin innervated by a single nerve
why does C1 not have a dermatome
it doesnt have an afferent component
where do the sensory afferent fibres synapse
in thalamus and spinal ganglia
what does the conus medullaris continue as at the end of the spinal cord
filum terminale
