Module 1 - anatomy of the brain Flashcards
the central system is the ______ and _____ centre
integrating and commanding
cerebrum contains 83% of brain volume and is divided into:
cerebral hemisphere and diencephalon.
the _______ contains 50% of neurons.
cerebellum.
neurons are highly specialised, excitable cells, provide rapid communication and have high_______ rate
metabolic
glial cells provided structural support, insulation and….
regional metabolism.
grey matter (neuron cell bodies) …
nucleus (CNS) and ganglion (PNS).
white matter (myelinated axons)….
tract (CNS) and nerve (PNS)
caudal
toward the tail
rostral
toward the nose
spinal cord extends from the____ to the_____
foramen magnum to first or second lumbar vertebra
enlargements of spinal cord
cervical and lumbar where nerves for upper and lower limb arises.
conus medullaris
end of spinal cord - tapering conical structure below the lumbar enlargement
filum terminale
anchors spinal cord to coccyx.
cauda equina
roots of nerves that arise from the lumbar, sacral and coccygeal regions of spinal cord and travel down the vertebral column.
posterior (dorsal) horns
incoming terminals from peripheral sensory neurons + inter-neurons
anterior (ventral) horns
motor neurons that go to the periphery + inter-neurons
dorsal roots (afferent fibres)
connects with dorsal root ganglion - sensory axons to the cord from spinal nerve.
ventral roots (efferent fibres)
motor axons to muscle/organs through mixed spinal nerves.
enlarged grey matter in____and _____ regions as more neurons muscles of lower and upper limbs.
cervical; lumbar
white matter increases in dorsal____from lumbar to______ regions - reflects increasing addition of sensory fibres from addition of sensory fibres from caudal to rostral truck regions.
column: cervical.
paralysis
temporary or permanent loss of motor control.
paraesthesia
sensory loss
the brain contains__ventricles
4
cerebrospinal fluid (CSF) is produced by______ _____. it fills cerebral ventricles and spinal cord as well as the ______ space
choroid plexus: subarachnoid space.
CSF has a constant turn over rate of
500mL/day produced and drained.
CSF is drained into venous sinus through the…
arachnoid granulations.
the functions of CSF are…
buoyancy, protection, chemical stability.
location of puncture for CSF sampling is…
lumbar.
CSF flow pathway..
lateral ventricles to the third ventricle through the intraventricular foramen. the third and fourth ventricle are connected to each other by the cerebral aqueduct. CSF then flows in the subarachnoid space through the lateral and median apertures.
cerebral aqueduct
connects the third and fourth ventricles.
interventricular foramen
connects lateral ventricles. to third ventricle.
lateral aperture
holes in 4th ventricle that allows CSF to pass through. also called foramina of lushke.
components. of the lateral ventricles
anterior horn, body, posterior horn, and inferior horn
choroid plexus produces CSF in…
body and inferior horn of the lateral ventricles.
third ventricle is located….
between lateral ventricle and cerebral aqueduct, choroid plexus in the roof.
fourth ventricle is located….
between cerebellum and pons/medulla
the roof/floor the fourth ventricle is formed by….
superior medullary velum and the inferior medullary velum (choroid plexus). The floor is formed by the brainstem.
the fourth ventricle has three openings..
2 lateral apertures and 1 median aperture.
hydrocephalus
accumulation of fluid in the spaces of the brain - due to increase production of CSF, disturbance in absorbance into venous sinuses.
Gyri
ridges.
sulci
shallow grooves.
fissure
an opening; a groove; a split.
what sulcus separates the frontal and parietal lobe
central sulcus.
what sulcus separates the temporal, parietal and frontal lobes
lateral sulcus
what fissure separates the cerebrum and cerebellum…
transverse fissure.
what sulcus separates the parietal and occipital lobe?
parieto-occipital
insula cortex
lies medial to lateral sulcus.
function of meninges
cover and protect CNS. protect blood vessels and enclose venous sinuses. contain CSF and form partitions in skull.
Three layers of meninges
dura, arachnoid, pia
dura mater
tough mother, outer layer, protecting the brain and spinal cord.
two layers of dura mater function..
periosteal layer and meningeal layer - separate and form dural venous sinuses.
dura mater extends inwards to form..
flat partitions to subdivide the cranial cavity and limit excessive movement of the brain within the cranium
dura mater forms partitions between…
two cerebral hemispheres (falx. cerebri), cerebellum and. cerebrum (tentorium cerebelli), two cerebellar hemispheres (falx cerebelli)
falx cerebri..
lies in medial sagittal plane, partially separates cerebral hemispheres.
falx cerebri is attached to…
bony projection anteriorly (crista galli) and to upper surface of tentorium cerebelli posteriorly.
tentorium cerebelli
lies in the horizontal plane, separates cerebrum from cerebellum.
falx cerebelli
smaller dural fold runs along the vermis of the cerebellum and separates two cerebellar hemispheres.
subdural space…
space between dura mater and arachnoid mater - very narrow, contains film of fluid, may be enlarged by bleeding.
arachnoid mater..
delicate transparent membrane - connected to the pia mater by fine strands of connective tissue (arachnoid trabecula)
subarachnoid space..
a space in the meninges beneath the arachnoid membrane and above the pia mater that contains the CSF - contains blood vessels.
cisterna magna
large area of CSF collection between the cerebellum and the medulla.
superior cistern..
also called the superior cerebellar cistern; an enlarged region of subarachnoid space above the cerebellum below the tentorium cerebelli.
interpeduncular cistern…
lies between the peduncles. contains bifurcation of basilar artery
pontine cistern
lies over the pons.
arachnoid villi (granulations)
help recycle CSF to blood; look like little warts; allow CSF to general circulation and drain via venous sinuses.
superior sagittal sinus…
a venous sinus located in the midline just dorsal to the corpus callosum, between the two cerebral hemispheres.
Flow of CSF
lateral ventricle -> 3rd -> 4th -> arachnoid space -> out arachnoid villi into blood stream.
pia mater..
delicate membrane, follows contours of brain, including sulci.
pia mater characteristics…
enmeshes blood vessels, sends prolongations into brain tissue along with blood vessels (perivascular space), helps form the roof of ventricles, closely associated with choroid plexus and ependyma
perivascular space…
space filled by blood vessels that penetrate the pia mater and enter the neural tissue where nutrient exchange occurs.
ependyma…
membrane lining the central canal of the spinal cord and the ventricles of the brain.
spinal meninges….
dura mater, arachnoid mater, pia mater - NO PERIOSTEAL layer.
spinal meninges: subarachnoid space…
between arachnoid and pia mater meninges, contains CSF - because there is not periosteal layer, there is an epidural space which contains fat tissue and is largest at L2 where spinal cord ends.
epidural anaesthesia…
regional anaesthesia produced by injecting mediation into the epidural space of the lumbar or sacral region of the spine.
lumbar cistern…
subarachnoid space inferior to medullary cone that contains cauda equina and CSF.
cistern…
reservoir or water tank.
spinal meninges; pia mater specialisation..
denticulate ligament - supports the spinal cord within dural sheath to secure spinal cord in place
filum terminale - fibre running from conus medullaris to tail bone, anchoring ends of spinal cord for extra support of spinal cord.
filum terminale
fibrous extension of the pia mater; anchors the spinal cord to the coccyx
meningitis..
inflammation of the pia-arachnoid mater.
internal carotid artery..
artery that supplies blood to the brain, eyes, eyelids, forehead, nose, and internal ear.
basilar artery…
an artery, formed by the fusion of the vertebral arteries, that supplied blood to the brainstem and to the posterior cerebral arteries.
vertebral artery…
one of the important blood vessels that enter the brain from the back of the skull
the basilar artery divides into two…
posterior cerebral arteries.
the internal carotid artery branches into…
anterior and middle cerebral arteries.
circle of willis (cerebral arterial circle)…
R/L posterior cerebral arteries R/L posterior communicating arteries R/L internal carotid arteries R/L anterior cerebral arteries anterior communicating artery
circle of willis function..
- equalises blood pressure in the brain
- provided alternative channels if one vessel becomes blocked.
posterior cerebral arteries.
two large arteries , arising from the basilar artery, that provide blood to posterior aspects of the cerebral hemispheres, cerebellum, and brainstem, 3rd and lateral ventricles.
anterior cerebral arteries.
two large arteries, arising from the carotids, that provide blood to the anterior poles and medial surfaces of the cerebral hemispheres.
middle cerebral arteries
two large arteries, arising from the internal carotid arteries, that provide blood to most of the lateral surfaced of the cerebral hemispheres
Blood brain barrier
formed by tight junction between the endothelial cells lining the brain capillaries to create a selective barrier for nutrients which serves as a protective mechanism to maintain a stable environment for the brain.
stroke results in……
reduction of blood supply to the brain - occlusion of a cerebral artery.
ischemic stroke
a type of stroke that occurs when the flow of blood to the brain is blocked.
hemorrhagic stroke
cerebral blood vessel rupture.
stroke-related dysfunction: anterior cerebral artery
contralateral hemiplegia (one artery) or bilateral paralysis (two arteries) and impaired sensation - greatest in lower limb
stroke-related dysfunction: middle cerebral artery
severe contralateral hemiplegia and impaired sensation - greatest in upper limb and face.
SEVERE aphasia if the dominant hemisphere is affected.
stroke-related dysfunction: posterior cerebral artery
contralateral homonymous hemianopsia (visual loss in half the visual field in both eyes)
blood drainage of the brain
fine veins (brain) -> pial venous plexuses -> cerebral veins -> dural venous sinus (emissary veins e.g., scalp and face) -> internal jugular vein -> heart.
emissary veins
connect dural venous sinuses with veins outside the skull - a potential source of infection into cranial cavity
rupture = subdural hemotoma.
dural venous sinuses
large veins in the dura mater that drain the cranium - collect venous blood from the brain and direct it into the internal jugular veins of the neck.
subdural hemotoma
collection of blood under the dura mater.
venous sinuses
blood-filled space between two layers of dura mater. they receive venous blood from scalp and also receive CSF
superior sagittal sinus
lies along the superior border of the falx cerebri - joins the transverse sinus (right). arachnoid vili drain the CSF into the superior sagittal sinus.
inferior sagittal sinus
runs within the inferior margin of the falx cerebri and joins the straight sinus.
straight sinus
- within tentorium cerebelli
- joins left transverse sinus.
transverse sinus
LEFT continuous with straight sinus
RIGHT continuous with superior sagittal sinus.
sigmoid sinus
- forward continuation of transverse sinus
- opens into internal jugular vein.
cavernous sinus
lateral to the pituitary gland, linked with venous channels
- drains into the superior sagittal sinus: transverse sinus
- drains into the inferior sinuses: internal jugular vein.
posterior spinal arteries
supply posterior (dorsal) horns and posterior (dorsal) columns.
anterior spinal arteries
supply anterior (ventral) and lateral columns, gray matter (except for dorsal horn)
radicular arteries
supply the spinal nerves.
posterior and anterior spinal veins drain blood into the……
internal vertebral venous plexus.
internal vertebral venous plexus
located within the epidural space
runs the entire length of the epidural space and continues superiorly through the foramen magnum to connect with dural venous sinuses in the cranial activity.
spinal cord strokes are typically……
ischemic - occlusion of posterior or anterior arteries.
functional areas of cerebral cortex
motor areas, sensory areas, association areas.
frontal lobe of cerebral cortex
executive function, impulse control, long-term planning (frontal cortex), motor function (primary motor cortex), speech (Broca’s area).
gyrus’s of the frontal lobe….
pre-central gyrus located posterior to the superior, middle and inferior frontal gyrus.
what separates the inferior frontal gyrus and the middle front gyrus?
inferior frontal sulcus.
what separates the middle frontal gyrus and superior frontal gyrus?
superior frontal sulcus.
location of central sulcus
separates frontal and parietal lobe.
location of pre-central gyrus
anterior to central sulcus.
where is the primary motor cortex located?
pre-central gyrus of frontal lobe
what does the primary motor cortex control?
a contralateral skilled voluntary movements of skeletal muscles (supplies 30% of axons to the corticospinal tract)
controls most precise muscles in the body
pre-central gyrus damage
occlusion/rupture of the anterior cerebral artery.
- contralateral hemiplegia
- greatest in lower limbs.
anterior cerebral artery supplies ___ aspect of cerebral hemispheres and ___ _____
medial; basal nuclei
middle cerebral artery damage results in
contralateral hemiplegia, greatest in the upper limbs and face regions.
middle cerebral artery supplies all the _____ surface of cerebral hemispheres
lateral
premotor cortex of frontal lobe includes……
superior, middle and inferior frontal gyri.
premotor cortex functions
planning movement, coordinating movement, controls learned motor skills - supplies 30% of corticospinal tract.
supplementary motor area
the area of secondary motor cortex that is within and adjacent to the longitudinal fissure - planning of complex movements.
cingulate gyrus
a strip of limbic cortex lying along the lateral walls of the groove separating the cerebral hemispheres, just above the corpus callosum
damage to supplementary and cingulate motor areas result in…..
loss of desired skilled movements and speech
inferior frontal gyrus can be broken into three subsections…
opercular, triangular, orbital.
opercular and triangular subsections of the inferior frontal gyrus are associated with what brain region?
broca’s region of language
what generates the motor programme for larynx, tongue, cheeks, and lips for speech projection?
opercular and triangular parts of the inferior gyrus.
The broca’s area is present in 1 or 2 hemispheres?
one
damage to broca’s area generates…
difficulty writing or speaking words but comprehension intact.
damage to middle cerebral artery can cause severe…..
aphasia if the dominant hemisphere is affected.
prefrontal cortex has extensive connections to…
parietal, temporal and occipital lobes.
components of the prefrontal cortex…
involved in intellect, complex learning abilities, planning, memory, and emotional control.
the prefrontal cortex measures____
slowly
dysfunction of the prefrontal cortex is associated with….
schizophrenia, ADD, etc.
the parietal lobe lies posterior to the______ sulcus and is composed of a superior and inferior parietal____ which is separated by the _____ sulcus
postcentral; lobe; intraparietal.
the post-central gyrus contains what?
primary somatosensory cortex.
the sensory homunculus receives information from the…
contralateral side
damage to the post-central gyrus results in occlusion/rupture of a branch of the anterior cerebral artery which causes….
occlusion/rupture of a branch of the anterior cerebral artery which causes contralateral sensory loss and is greatest in lower limbs.
damage to post-central gyrus results in occlusion/rupture of a branch of the middle cerebral artery which causes…..
contralateral sensory loss and is greatest in upper limbs.
superior parietal lobe corresponds to what cortex….
somatosensory association cortex.
somatosensory association cortex function….
integrating different sensory inputs to produce a comprehensive understanding of position of limbs, location of touch and pain, shape and weight/texture of an object.
damage to the somatosensory association cortex…
tactile agnosia - unable to recognise objects without looking at them.
inferior parietal lobe is associated with what cortex….
multimodal association cortex.
the temporal lobe consists of a superior, middle and inferior temporal___ which the superior and middle is separated by a superior temporal____ and the middle and inferior separated by a inferior temporal____
gyrus, sulcus, sulcus
the ____ margin of the superior temporal gyrus processes ____ information and is sensitive to ___ , rhythm, and loudness
superior, auditory, pitch.
unilateral damage to the primary auditory cortex (middle cerebral artery) results in…..
hearing loss
the temporal lobe is associated with what cortex?
primary auditory cortex.
bilateral damage to the primary auditory cortex results in…..
cortical deafness
the ____ part of the superior temporal gyrus is associated with the auditory ____ cortex and more specifically is the location of ______ area.
posterior, association, wernicke’s
Wernicke’s area is a ______ language area which permits recognition of ____ and ____ language
sensory, spoken, written.
damage to wernicke’s area results in….
receptive aphasia (fluent)
accurate fasciculus
a bundle of axons that connects wernicke’s area (superior temporal gyrus) with Broca’s area (inferior frontal gyrus); damage causes conduction aphasia.
language areas: frontal cortex…
Broca’s area and supplementary motor area (language motor production) and lateral prefrontal cortex (processing of comprehension and word analysis)
language areas: parietal cortex…
supramarginal angular gyri which is responsible for interpretation of spoken and written language.
language areas: temporal lobe…
associative cortex which coordinates auditory and visual aspects of language when naming objects of reading
occipitotemporal sulcus
groove just inferior to the inferior temporal gyrus,
located on the ventral surface of the temporal lobe
lateral to the collateral sulcus that tuns parallel to it
collateral sulcus
divides lingual and parahippocampal gyri from fusiform gyrus.
parahippocampal gyrus
a fold of tissue near the hippocampus that is often included in the limbic system - separated by both collateral sulcus and rhinal sulcus - lies posterior to the uncus.
uncus and parahippocampal gyrus
primary olfactory area; bottom of brainstem and is in the temporal lobe
uncus is an anterior extremity of the parahippocampal gyrus
what is located within the temporal lobe
hippocampus, with the amygdala right at the front.
septum pellucidum
thin membrane that separates lateral ventricles.
structure of hippocampus
composed of fornix (arches of the hippocampus) and the fimbria
location of the thalamus
diencephalon.
fornix
a long projection from the hippocampus that connects to other nuclei in the limbic system
crescent shaped hippocampus sits adjacent to the _____. the hippocampus contains fibres of temporal parts called_____ which can thicken. in the midline under the corpus callosum, these fibres are the ______
uncus, fimbria, fornix.
insular lobe
found deep beneath the lateral sulcus, associated with memory and interpretation of taste, modulates emotion/self-awareness.
occipital lobe is separated from parietal lobe by _____ -____ sulcus and is home to the primary ____ cortex which has the ____ sulcus dividing it.
parietal-occipital; visual; calcarine.
the occipital lobe is supplied by the….
posterior cerebral artery.
damage to the posterior cerebral artery results in….
cortical blindness due to direct damage to the primary visual cortex.
visual association areas of the occipital lobe communicate with primary visual cortex to interpret visual ____ and ____ things we see, except for faces (temporal associative cortex). visual associative area damage (posterior cerebral artery) results in visual _____ or hemianopsia.
stimuli, identify, agnosia
dysfunction is posterior cerebral artery results in…
contralateral homonymous hemianopsia (visual loss in half the visual field)
cerebral white matter is responsible for communication between…
cerebral areas and between cerebral cortex and lower CNS areas.
white matter consists mostly of…..
myelinated axons bundled into large tracts.
projections of white matter….
extend vertically from brain to spinal cord within one hemisphere forming the internal capsule.
internal capsule
band of projection fibres that runs between basal nuclei and the thalamus.
commissural tracts of white matter….
cross from one hemisphere to the other e.g., corpus callosum
structure of corpus callosum…
anterior portion contains the rostrum and genu, more medial, lies the body and the splenium makes up the posterior portion of the corpus callosum (temporal and occipital lobe)
anterior commissure tracts
bundles of axons that connects the two hemispheres of the cerebral cortex, more specifically the middle and inferior temporal gyri.
association fibres (shortest fibres)
connects lobes and gyri within the hemispheres.
diencephalon contains and is associated with…
thalamus, hypothalamus, epithalamus - associated with 3rd ventricle.
components of the thalamus
egg-shaped structure which makes up 80% of the diencephalon - forms the superolateral walls of the third ventricle.
structure of the thalamus..
contains about a dozen nuclei with an intermediate mass lying medially which serves to connect each thalamus together.
at the posterior end of the thalamus lies the _____. this is responsible for ____ information. the thalamus allows different structures to connect to different cortical regions but does not have _____ information pass through.
pulvinar, visual, auditory.
the hypothalamus is located _____ to the thalamus and is separated by the ______ sulcus. it forms the inferolateral wall of the __ ventricle, extends form the optic _____ and is superior to the brainstem.
below: hypothalamic: third: chiasma.
what is an early sign of damage to the hypothalamus?
visual field defects (encroaching on the optic chiasm or optic tract)
components of epithalamus
pineal gland and the roof of the third ventricle - contains calcium salts.
pineal gland generates..
melatonin.
components of the basal ganglia
corpus striatum, subthalamic nuclei, substantia nigra
the corpus striatum of the basal ganglia is composed of…
lentiform and caudate nucleus.
lentiform of the corpus striatum of the basal ganglia contains 2 components….
putamen and globus pallidus.
caudate nucleus of the corpus striatum has a head, body and tail and wraps around the ______ nucleus. at the tail of the caudate nucleus lies the _____ nucleus.
lentiform; amygdala (limbic system).
the posterior limb of the internal capsule fibres runs between
lentiform nucleus and thalamus.
the anterior limb of the internal capsule fibres run between
lentiform and caudate nucleus.
globus pallidus + putamen nuclei
body component of the lentiform nucleus of the corpus striatum of the basal ganglia whilst the putamen lies more lateral
the basal ganglia serves as a tool box for movement. it also serves as a break for the excitatory input provided by the_______ via inhibition of unnecessary movements. the break can be released by input from the cerebral cortex and the ______ _____ to start movement
thalamus; substantia nigra.
at rest, the globus pallidus of the lentiform nucleus _______ the thalamus which results in ___ motor activity. to initiate the movement, the cortex activates_____ which inhibits the globus pallidus, releasing thalamus from____ and activating motor cortex (inhibiting the inhibitor = activation)
inhibits; no ; putamen; inhibition.
the basal ganglia influence the function of spinal cord motor neurons directly or indirectly?
indirectly.
cause of Parkinson’s disease
substantia nigra dopamine neuron degeneration.
what does the brainstem consist of?
midbrain, pons, medulla.
the brainstem provides a pathway for _____ ___ running between forebrain ,cerebellum and ___ ___
axonal tracts: spinal cord
components of midbrain
cerebral peduncles, superior and inferior colliculi, substantia nigra, red nucleus, cranial nerves, cerebral aqueduct, and superior cerebellar peduncles.
cerebral peduncles include
axons that descend from the cerebral cortex to the brainstem and spinal cord.
function of cerebral peduncles?
anchor the cerebrum to the brainstem.
what structure does the cerebral aqueduct sit in the middle part of?
cerebral peduncles.
superior colliculi (Midbrain) are responsible for
visual reflexes - receive input from the retina/visual cortex and project vision-related areas in the cortex.
superior colliculi are concerned with the detection of…
movement of objects in the visual field.
superior colliculi relay ___ information to neurons innervating the ___ that control eye movement.
visual; muscles.
inferior colliculi (midbrain) are responsible for
auditory reflexes - act in reflexive responses to sound
inferior colliculi relay…
auditory information from hearing receptors of the ear to sensory cortex.
location of substantia nigra
midbrain - above cerebral peduncle.
what pigment does substantia nigra contain?
melanin.
what are the two functional components of the substantia nigra of the midbrain?
pars compacta and para reticulate
pars compacta of substantia nigra
thin lateral section of the substantia nigra - responsible for dopamine neuronal activity.
pars reticulate of the substantia nigra has similar connections to the _____ ____ which surrounds inhibitory input to the ______
globus pallidus; thalamus.
location of red nucleus
midbrain - above the substantia nigra.
the red nucleus of the midbrain contains
rich blood supply and contains iron pigment.
the red nucleus also acts to relay..
descending motor pathways.
superior cerebellar peduncle connects…
cerebellum to midbrain - they are the major output fibres from the cerebellum.
the superior cerebellar peduncle function?
proprioception.
location of pons
middle of brain stem - located in the middle cerebellar peduncle (4th ventricle emerges)
the pons are composed of both _____ sensory and _____ motor tracts
ascending and descending.
what is the key nuclei within the pons
pneumotaxic centra (respiratory centre).
middler cerebellar peduncles connects…
pons to cerebrum - convey motor and sensory command information.
components of the medulla?
pyramids, olives, gracile and cuneate tubercles, 4th ventricle and inferior cerebellar peduncle.
pyramids of medulla (open medulla) are formed by..
large pyramidal (corticospinal) tracts descending from the motor cortex.
pyramid decussation of medulla (closed medulla) are formed by..
axons of pyramidal tracts
axons of the pyramidal tracts within the closed medulla _____ over to the _____ side at the level just above the _____ -spinal junction
cross; opposite; medulla
olives of the medulla are located in the….
open medulla
olives of the medulla contain…
inferior olivary nuclei.
functions of the inferior olivary nuclei of the olives of the medulla?
relay sensory information to the cerebellum
what are the two tubercles of the medulla? where are they located?
cuneate and gracile tubercles - located in closed medulla.
cuneate and gracile tubercles of the medulla receive…
somatosensory information from upper and lower body parts.
inferior cerebellar peduncle comprises fibres to and from…
the medulla/spinal cord to cerebellum.
the inferior cerebellar peduncle of the medulla carries…
sensory and motor information, important for balance and posture.
what are the medulla’s role in maintaining body homeostasis?
cardiovascular centre - respiratory centres.
the medulla has a functional association with what region in homeostasis maintenance?
hypothalamus sends autonomic commands to medulla to influence smooth muscle and gland function.
reticular formation is composed of clusters of _____ ____ scattered throughout midbrain, pons and medulla. it works in governing the arousal of the brain via the ______
gray matter; thalamus.
the reticular formation is involved in ______. this is. a process in which the brain learns to ignore repetitive stimuli. it is inhibited by sleep centres in the hypothalamus, _____ by alcohol and injury may result in_____
habituation; depressed; coma.
we have 12 pairs of ______ nerves; 10 associated with the _____ and 2 attached to that_____. they are mixed with sensory/____ nerves
cranial; brainstem; forebrain; motor.
fibres of the olfactory nerve and optic nerve are associated with what brain region?
forebrain
oculomotor nerve and trochlear nerve are associated with what brain region?
midbrain
trigeminal nerve, abducens nerve, facial nerve and vestibuolocochlear nerve are associated with what brain region
pons
glossopharyngeal nerve, vagus nerve, accessory nerve and the hypoglossal nerve are associated with what brain region?
medulla
the olfactory nerve is a ____ nerve that runs from the nasal _____, passes through____ plate of ethmoid bone to synapse on the olfactory_____. damage to this nerve causes_____.
sensory; mucosa; cribriform; bulb; anosmia.
location of olfactory cortex
medial surface of the temporal lobe, in a region called the uncus.
what region is associated with olfactory memory?
hippocampus
the optic nerve arises from the _____ fo the eye. each optic nerve passes through its optic____ of the orbit. nerves converge to form the optic ______
retina; foramen; chiasm.
anterior fossa bones
cribriform plate (ethmoid bone), frontal bone, lesser wing of the sphenoid bone.
middle fossa bones
greater wing of sphenoid bone, temporal bone.
posterior fossa bones
parietal and occipital bone, hypoglossal canal.
the foramen ovale (branch of the trigeminal nerve) is part of what fossa?
middle
what type of foramina does the cribriform plate have?
olfactory (nerve)
superior orbital fissure of sphenoid bone
between greater and lesser wing on the sphenoid bone, transmits oculomotor, trochlear, and abducens nerves. also a branch of ophthalmic CN V1
inferior orbital fissure
fissure in the orbit floor between maxilla and greater wing of sphenoid.
what does the subdural space separate in the spinal cord?
dura from the periosteum of surrounding bone
where do the anterior and posterior nerve roots penetrate the dura a the….
intervertebral foramina.
what is separated from the dura by the subdural space (spinal cord)?
arachnoid.
spinal cord structure
dura mater - subdural space - arachnoid - subarachnoid space - pia mater.
dorsal funiculus
the white matter of the spinal cord lying on either side between the posterior median sulcus and the dorsal root.
- this are included the dorsal columns which contains the fasciculus gracilis and, higher in the body, the fasciculus cuneatus
- ascending sensory tracts.
the lumbar level has the least amount of fibres in the _______ funiculus
dorsal
what do you call a region where CSF accumulates due to spaces between the two innermost brain layers
cisterns.
oculomotor nerve axons extend from ventral ___ and pass through the superior ____ fissure. it contains both an inferior and _____ branch
midbrain; orbital; superior.
oculomotor nerves are _____ axons that play a part in voluntary movement of the ___ via eyelid opening via _____ control and pupil constriction and focussing via the ____ motor axons.
motor; eye; somatic; parasympathetic.
trochlear nerve axons emerge from dorsal ____, course ventrally ____ the midbrain and pass through the superior and _____ fissure
midbrain; around; orbital.
what is the only cranial nerve that emerges from dorsal brainstem?
trochlear nerve.
trochlear nerve are ____ axons and supply ____ axons to the superior oblique muscle. this muscle has a ____ that hooks around a pulley called a ______
motor; somatic; tendon; trochlea.
what nerve supplies somatic motor axons that move the eye downward and laterally?
trochlear nerves.
damage to what nerve causes double vision and inability to rotate eye inferolaterally
trochlear nerves.
trigeminal nerve are 3 fold and are the largest cranial nerve. their axons extend from face to _____ and _____ to muscle. cell bodies of sensory neurons are located in large terminal_____
pons; pons; ganglion.
