Neuroanatomy S18-23 Flashcards
What is the white matter made of?
Axons and dendrites with few cell bodies
What is grey matter made of?
mainly cell bodies and non myelenated neurones
What is Neuropil?
The intermingles processes between the cell bodies of neurones
What is the Dura mater?
Fibrous sheet of collagen fibres and a few elastic fibres it has a latticed appearance.. there are two layers to the dura mater the outer endosteal layer and the inner meningeal layer the dura mater proper.
What is arachnoid mater?
Poorly vascularised membrane of collagen elastin and reticulin fibres with tight jundtions it covers the whole brain with few dips
What is the pia mater?
Covers the entire CNS it makes the Blood brain barrier, there are underlying astrocytes beneath the it called pia glia thre are connective element of eacha re contiueous and for trabeculae
What is contained in the frontal lobes?
the primary motor cortex and prefrontal cortex
What is contained in the temporal lobes?
Primary auditory cortex, auditory association cortes
What is in the occipital lobes?
The primary and secondary visual cortex
What does the cerebellum do?
Motor control of balance posure muscle tone and coordinates movement
What is the insula?
The floor of lateral sulcus its own lobe
What is the opercula?
Lips as part of temporal frontal and parietal that overly the insula
What is the longitudinal fissure?
The one down the middle front to back.
what lies at the bottom of the longitudinal fissure?
the corpus callosum
What are optic tracts?
the are connection that go from the optic chiasma to the cortexies
What are the mamillary bodies?
Rounded nodules behind optic chiasm involved in Papez circuit
Where is the hypothalamus?
Above the optic chiasma up to mamillary bodiesonly part of diencephalon that is visible on the outside of the brain
What are the crura ceribri or cerebral peduncles?
They are two large masses of white matter emering behind the mammillary bodies on each side from the cerebral hemisphere they pass backwards converding at the upper border o the pons
What are the functions of the parietal lobe?
Primary sensory area, sensory information processing, complex idea formation also language and mathmatical functions and cisuospatial functions
What is the frontal cortex involved with?
The frontal lobe is involved in problem solving spontaneity memory language judgement impulse control and social sexual behaviour
What is the temporal lobe involved in?
The primary auditory cortex, and memory and emotion
What is the occipital lobe?
contains areas for visual association.
What is formed in the space between the outer and inner membranes of the dura mater?
the venous drainage the sinus venousis
What is the superior sagittal sinus?
where the falx cerebri attaches to the skull
What is the inferior sagittal sinus?
The free border of the falx cerebri
What is the tentorium cerebelli?
It separates the posterior craial fossa and the cerebellum
What is the straight sinus?
Within tentorium cerebeli that attaches at the attachement to the falx cerebri
What is the tentoral incisure?
The horseshoe like space between the free concave border of the tentorium and the dorsum of the sphenoid
What is the foramen of magendie?
The midline communication between the 4th ventricle and the subarachnoid space
What is a subarachnoid cistern?
Part of the brain which is full of CSF an area
Where are the main cisterns of the brain?
The cerebelomedurally on dorsal surface of medula, pontine cictern ventral surface, interpeduncular cistern containing circle of willis, latteral fissure one and supperior cistern cotaining great vei of galen, cisterna ambiens wich encircle midbrain
What is the foramen of Luschka?
It is a lateral communication with the 4th ventricle and the subarachnoid space
Describe the layers of blood brain barrier?
The endothelial cells lining blood vessels with tight junctions, basement menbranes lack genestrations in CNS, pericutes they wrap around endothelium, and astrocytes with foot like processes
What does extra dural mea?
Between the skull and dura mater
What happens in extra dural haemorrage?
Stripes dura from boe and compresses the brain after head injury from meningeal artery
What is subdural?
Between the dura and arachnoid mater
What is a subdural haemorage like?
crescent shaped onCT after RTC tears of bridging veins
What si subarachnoid?
Between arachnoid and ia mater
What can cause a subarachoid haemorrage?
Blood between arachnoid and pia oftem from berry aneurysm blood srrouds the brain and fills the sulci, predominantly near the site of injury sever headache
What is intracerebreal?
Bleedig within brain tissue from small perforatig vessels
What is Amaurosis fugax?
Temporary loss of vision to one eye carotid plaue occluding central redial arteru
What supplies the anterior circulation of the brain?
The internal carotid arteries
what supplies the posterior circulation of the brain?
The vertebral/ basilar arteries
Which arteries are part of the the anterior circulation?
the anterior cerebral artery and the middle cerebreal artery
Where does the anterior cerebral arter supply?
Corpus callosum and the medial portion of the corticies either side of the longditudinal fissure
What is the purpose of the anterior communicating artery/
It cannon compensate fully but some could offer a partial blood supple
What does the middle cerebral artery supply?
It rund through the silvian fissure lateral sulcus and runs over the insula it supes most of the lateral teritories of the hemispheres
What do the vertebral arteries join to make?
The basilar artery
What is the most anterior artery of the posterior circulation?
The osterior cerebral artery, doing inferior an dmetial temporal lobes and posterior occupital lobes
How many arteries supply the cerebellum?
3 posterior inferior cerebellar, anterior inferior cerebelar, superior cerebellar artery
What connects the two circulations of the brain?
The posterior communicating artery
What are external cerebral veins?
They are veins that train into the dural venous sinses
Where do the internal carotid arteries enter the skull?
The carotid canal, it enters through the temoral bone and passes anteriorly and upwards not vertically
Where do the vertebral arteries enter the skull?
The foramen magnum.
Where do most venous blood the skull?
The jugular foreman
What does the middle meningeal artery pass do?
Skull dura ans muslces of skull
What blood vessel passes through the opti canal/
The ophthalmic artery
What artery passes though the foramen spinosum?
The middle meningeal artery
What are internal cerebral veins?
veins in the brain tissue tat become external cerebral veins when they reach the surface
What are the main external cerebral veins/
the superficial middle cerebral vein
What passes through the cavernous sinus?
The occulomotor nerve the opthalmic maxillary division of the trigeminal nerve the abducens nerve trochlear
Where is CSF formed?
in choriod plexus on the ependymal lining of the ventricle
What separates the anterior cranial fossa from middle?
The lessser wing of the sphenoid
What bones make up the anterior cranial fossa?
The ethmoid, sphenoid and frontal bones
Which bone forms the roof of the orbit?
The frontal bone
What sits in the anterior cranial fossa?
The frontal lobes
What sits in the middle cranial fossa?
The temporal lobes
What sits in the posterior cranial fossa?
The cerebellum
What forms the middle cranial fossa?
The temporal the petous, and squamous, and the ethmoid
What forms the foramen magnum?
The occcipital bone
What is the part of the ethmoid bone in anterior cranial fossa?
The cribriform plate with small holes, there is the foramina for a sensory nerve ethmoidal arteries and veins
What is the crista galli and its function?
The ridge in the middle of the ethmoid bone and it is the point of attachment of the falx cerebri.
What are the exit foramina for the middle cranial fossa?
Superior orbital fisure, carotid canal, foramen laccerum, foramen rotundum, foramen ovale, optic canal foramen spinosum
What is the sella turcica?
The depression in the middle cranial fossa in the ethmoid bone and it holds the pituitary gland
What passes though the cavernous sinus?
Internal carotid, 3,4,6 and opthalmic of 5th nerves
What happens in meckel’s cave?
this is where the ganglia for the trigeminal nerve lies
What does the optic canal carry?
The optic nerve and the opthalmic artery
What passes through the superior orbital fissure?
theerd 4th 6th CN for the eye muscles and opthalmic division of trigeminal nerve
What passes through the foramen rotundum?
Maxillary division of the trigeminal nerve
What passes through the foramen ovale?
the mandibular division of the trigeminal nerve sensory and motor fibres
What passes thought the foramen spinosum?
the middle meningeal artery
What does the tentorim cerebelli attach to?
The ridge on the petrous part of the temporal bone
What passes though the foramen magnum?
The spinal cord, vertebral arteries from subclavian, spinal accessory nerve, spinal arteries from the vertebral arteries
Where is the hypoglossal cannal?
Transmits hypoglossal nerve it is in posterior cranial fossa
Where do 9,10,11 leave?
The jugular foramina
Where does the facial nerve exit the skull?
Passes throug interal acoustic meatus through inner and midde ear and out through the stylo mastoid foramina
What is the triangle of danger?
The teeth to the frontal sinses blood from there can drain backwards through the orbit into the cavernous sinus which can cause intracranial infection
What hapens to the ophtalmic division of the trigmeinal nerve when it enters the orbit?
It splits into the lacrimal and nasocillary nerve and frontal that goes to the face
Which nerve innervates superior oblique?
The 4th CN Trochlear
What lifts the eyelid?
Levator palpebrae superioris
Which musles don’t pull in optical orbit?
Superior and inferior rectus
What corrects for contraction of inferior rectus?
Superior oblique intorts the eye tot counteract the extorsion from inferior rectus
What is the vestibular nucleus?
in the pons
What is the first bone of the ear from the outside?
maleus then incus then stapes
Which cranial nerve leaves the brain stem dorsally?
the trochlear nerve 4th
What is down the front of the medulla?
The ventral median sulcus
Where are the olives?
In the medula
Where do auditory signals go?
The go to the medial genuculate nucleus and the inferior colliculus
Where do visual signals go?
The lateral geniculate nucleus, and superior colucluls
What does tectum mean/
Roof its the top if we were an animal
What are the features of the tectum/
the colliculi
What are the main parts of the tegmentum?
The substansia nigra that produces dopamine, red nucleus and periaqueductal grey
Where is the exit of the 3rd cranial nerve from the brain?
from above the pons
Where is the 5th granial nerve exiting the brain?
At the edge of the pons
Which nerves arise at the bulboponitine sulcus?
Medially 6th , then7th and 8th are at pontomedullary angle also 9th and 10th
Where does the acessory nerve exit the brain?
Along the medulla a long way
Where does the hypoglossal exit the brain?
Above the 11 and 10th more medially
Which order neurons are the olfactory bulbs?
the 2nd order the first order ones are in the cribriform plate
Do the olfactory nerves pass through the thalamus?
No but all other senses do
How many fibres pass to the other side of the brain?
85% stay same 15% go opposite
Which retinal fibres cross?
The fibres from the medial retina which have a teporal field of view
Where to the nerves from the superior of retina go?
the erves that look down from the superor of the retina go through the parietal lobes
What is the optic nerve?
The neurons from one whole eye
What is the meeting point of the optic tract?
the optic chiasm
What is the optic tract?
the nerves from the chiasm to the lateral geniculate nucleus
What is the optic radiation?
The pathway from the lateral geniculate nucleus to the occipital lobe
What does homonamus mean?
The same field in each eye
What does hemianopia mean/
Loss of half of vision in one eye
What would a lesion of the right optic nerve lead to?
Right anopia, none of the signals from the right eye reach the brain so all sight is lost from this eye
What would a lesion of the right optic tract do?
It would stop the signals from the right temporal retina and left nasal retina which have views of the right nasa and left temporal fields giving a Left homonamous hemianopia
What woud a lesion of the temporal right eye do?
Loss of vision in a quater of their field a quadrantanopia
What does the 3rd ocranial do?
All occular muscles, but not lateral rectus and superior oblique also pupil and acommodation
What does the 4th nerve do?
It does superior oblique
What does the trigeminal nerve do?
The opthalmic:sensation to area above eyes ad front of nose including some of sinses also they eye ball and lacrimal gland
The maxillary: sensation to face below eyes, maxillary sinuses teeth as well
and Mandibular sensation to skin over mandible also has motor that does mastication muscles tensor tympani, sensory to anterior 2/3 of tongue.
What does the facial nerve do?
It does face expression muscles, sensory to ouside of ear, taste for ant 2/3 of tongue, lacimal gland secretion, salivary glands, and stapedius nuscle
What does the vestibulocochlear nerve do?
It has vestubular for balance cochlear for hearing.
What does the lossopharengea nerve do?
Carotid body senses and posterior third of tongue sensation and taste, pary of pharynx too aso parotid gland salivary also stylopharengeus muscle
What des vagus nerve do?
abdominal and other viscera some specific muscles
What does acessory nerve d?
Trapesius and sternocleidomastoid,
What are the wibbles called on the cerebellum called?
Folia
What are the tonsils of the cerebellum?
They lie on the inferior border of the cerebellum and in the midline
What is the central region of the cerebellum?
The vermis
What are the Two lobes of the cerebellum?
Anterior and posterior lobes separated by the primary fisure sometiems there are middle which splits posterior into horizinatal and posterior
How many cerebellar peduncles are there/
3 middle inferior superior
What is the most visible nucleus in the cerebellum?
The dentate nucleus pass to superior cerebellar peduncle
What do the floculi do?
Communucate with nodule and help with processing balance through the inferior cerebellar peduncle and most output go to vestibulus
What is processed by the medial and the vermis?
They receive proprioceptive information from the cerebellar nuclei.
What is the shape of the floor of the 4th ventricle?
The rhomboid fossa
Where are the gracile and cuneate tubercles?
The are bellow the ventricle on the posterior facing side
What are the gracile and cuneate fassiculi?
cell bodies and synapses for the crude touch and proprioception
What are medullary striae?
The are pontocerebellarfibres thatsplit the floor of the fouth ventricle into two parts
What is under the blue areas of the floor of the fourth ventricle?
locus coeruleus
What is the tip of the rhomboid fossa?
Obex
What is the area postrema?
the vomiting centre it is inside the obex
What are many of the bumps of the floor of the 4th ventricle?
The colliculi from the nucleus beneath it
What are many of the bumps of the floor of the 4th ventricle?
The colliculi from the nucleus beneath it
What type of tracts run between the hemispheres?
Commissural fibres
what type of tracts are in the corpus callosum?
Commisural fibres
What is the septum pellucidum?
the area between the anterior horn of the lateral ventricles
Where is the division between the thalamus and the hyothalamus?
The hypothalamic sulcus between the cerebral aqueduct and the interventricular foramen
what does the pineal body do?
It releases melatonin for circadian rhythm
What are the epithalamas?
hebenula pineal body and striae medullaris
What is the largest white matter structure?
The corpus callosum
What are the parts of the corpus callosum?
Genue at front rostrum body at middle, splenium and rostrum
What is the fornix?
It connects hippocampus to diencephalon above ventricle and conect to mamillary bodies
What does the anterior commisure do?
Olfactory and temporal lobes in hemispheres
What is the innermost gurus of the medial side?
The cingulate girus
What does the calcerine sulcus do?
Splits the occipital lobe containing primary visual sulcus
What is present in the visual area of the brain?
There is a striped layer in the grey matter from thalamus to 4th layer striae of genari
What are association fibres?
link areas in one region of the cerebral hemisphere
What are the areas involved with the olfactory system?
not thalamus, olfactory tract into medial olfactroy tohipothalamus , and lateral olfactory straiae goes to the uncus primary olfactory striae
Which areas are involves with the papez circuit?
Hippocampus, fimbria, fornix, mamillary body, mamilothalamic tract, thalamus, to cingulate girus, cinculum bundle to parahippocampal girus, enterinal cortex to the hippocampus also amygdala and hypothalamus
Where can you find the internal capsule?
Behind the cingulate girus.
What structures are involved in the basal ganglia?
the thalamus, the amygdala the caudate nucleus the putamen and hippocampus and fornix
What is the shape of the caudate nucleus?
Folows lateral ventricle latteraly in a c shape
Where is the amygdala?
It is just above the inferior horn of the hippocampus with caudate entering posteriorly
Where is the hippocamus?
It is unferior to the inferior horn of the lateral ventricle, floor it runs up into the fornix which joins at the centre that is above the thalamus
Where is the thalamus?
It is either side of the 3rd ventricle
Where is the lenti form nucleus?
inferior and slightly lateral to the superior horn
What makes up the lentiform nucleus?
The putamen and the globus pallidus
What are the basal ganglia involved in?
They are involved in the control of voluntary movement
What strucutes are around the lateral ventriles?
The caudate nucleus, the hippocamus
What is the stria terminalis?
Connects amygdala and septum and hypothalamus and follows the caudate nucleus
which cortex lie above he basal ganglia/
The insula and lateral fissure
What is the outermost projection fibres?
The extreme cortex
What is beneath the the extreme capsule?
claustrum
What is beneath the claustrm?
The external capsule
What is between the external and interna capsule?
The lentiform nucleus, including external putamen and globus pallidus
What is the corpus striatum?
The putamen and caudate
What is the nucleus accumbans?
The reward centre of the brain it is where caudate and putamen meet
What information passes through the superior cerebellar peduncle?
The ventral spinocerebellar or sensory balance and position
Whart passes through the middle cerebellar peduncle?
The motor outputs from the motor cortext and sensory inputs
What passes though the inferior cerebellar peduncle?
The vestibulocerebellar tract for balance from labyrinths
How many sacral vertebra are there?
5
How many lumbar vertebra are there?
5
How many thoracic vertebra are their?
12
How many cervical vertebrae are there?
7
What is the structureof a lumbar vertebra?
Large vertebral body, pedicles either side, transverse process spinous process articular process and a lamina that encircles the canal
What is the purpose of the vertebral body?
To bear the weight of the body above
What is the lamina of a vertebra for?
To encircle the spinal cord
What is the purpose of the transverse processes?
To serve as an attachment for muscles and ribs in thoracic ones
What des the articular articular processes of the vertebra do?
Theyarticulate with the vertebra above and below them
What is different about cervical vertebra to thoracic ones?
There is a different shape, the transverse process is small, it has vertebral foramina for the vertebral artery to supply the brain 2 pionts of the spinous process all but 7
What is the shape of the C1 Vertebra(atlas)?
Ring with vertebral foramina no vertebral body
What is the shape of the C2 vertebra(axis)?
Has a pointy bit odontoid peg from the body that allows the head to rotate.
How many curves of the spin are there?
3
What are the curves of the spine?
Cervical forwards, thoracic backwards (kyphosis), lumbar tat is forwards (lourdosis)
Which part of the spine has most lateral rotation?
cervical
Which part of the spine has the most Flexion/
lumbar
What type of joint is the inter vertebral disk?
Secondary cartilaginous joint. A composite after bone of hyaline cartilage middle layer of fibrocartilage with liquid centre then hyaline and bone again
What does the anterior spinal ligament do?
It connects the anterior side of the vertebral bodies
What does the posterior spinal ligament do?
It connects the posterior side of the vertebral bodies
What does the ligamentum flavum do?
It joins the lamina of the posterior wall of the vertebral canal
What are the boundaries for the spinal nerve exit foramina?
The pedicles inferior and superiorly and thelamina posteriorly and the vertebral body
What are the boundaries for the spinal nerve exit foramina?
The pedicles inferior and superiorly and thelamina posteriorly and the vertebral body
Which nerve root is most affected with a central disk prolapse/
The nerve root of the next segment down occasionally
Where does erector spinae go?
Along either side of the spine
Are the layers of dura adherent to the spinal canal?
No
What is the filum termialae?
The last part of the meninges
What is the filum termialae?
The last part of the meninges pia
What is the last part of the spinal cord?
The cordae quinquina
Where is spinal fluid taken from?
The lumbar puncture
What is damaged first by s slipped disk motor or sensory?
Sensory as ganglia is in the intervertebral foramina
What is the way the spinal cord nerves are named/
The nerve that is above the body for 1 to 7 then it is the nerve that comes below the body
What is the cross section of the spinal cord?
H shaped grey matter with lots of cell bodies
What do axons do?
Bring signals away from the cell body
Where is the corticospinal tract?
The posterior area and lateral side of the dorsal horn some in ventral middle bit
What signals do the ventral corticospinal tracts carry/
They have small amount of the motor sense from the ipsilateral cortex and then decusate at the level
What do the dorsal columns carry?
Vibration touch, 2 point descrimination and conscious proprioception
What do the ventral spinothalamic pathways do?
Extreme temperature change, pressure and pain
What does the spinocerebellar do?
The subconscious sensory information.
How do the sensory fibres enter spinothalamic?
They enter pass ipsilateral for a bit then decussate 1 r 2 levels above
How do the sensory fibres enter dorsal spinocerebellar?
ipsilateral
