Neuroanatomy Flashcards
What components make up the nervous system
CNS and PNS
What makes up the CNS
Brain and spinal cord
What makes up the PNS
12 pairs of cranial nerves
31 pairs of spinal nerves
What makes up the brainstem
midbrain
pons
medulla oblongata
What makes up the diencephalon
thalamus + hypothalamus
What are the principle cells of the CNS
Neurons
Glial cells
What are the subtypes of glial cells
astrocytes
oligodendrocytes
microglia
ependymal cells
What are neurons
Communicating cells that receive information from synapses and transmit it to other neurons/effector cells
Most neurons are multipolar, true or false
True
Describe astrocytes
Type of glial cell
star shaped
roles in support, maintaining BBB, environmental homeostasis
There are more neurons than glial cells in the CNS, true or false
FALSE
There is connective tissue present in the CNS, true or false
FALSE, no connective tissue in CNS
What is the role of oligodendrocytes
produce myelin in CNS only
Have numerous branches
Where do microglia originate from
bone marrow / homopoietic origin
What is the role of microglia
immune monitoring and antigen presentation
What are ependymal cells
ciliated epithelium that line the ventricles and produce CSF
What does grey matter contain
neuron cell bodies / soma
What does white matter contain
axons
Where is grey matter found in the CNS
Brain - outside
Spinal cord - inside
Where is white matter found in the CNS
Brain - inside
Spinal cord - outside
somatosensory information is found in the pre / post central gyrus
POST central gyrus
Somatomotor information is found in the pre / post central gyrus
PRE central gyrus
Where is the cingulate gyrus found
above the corpus callosum
What is the corpus callosum
huge band of white matter connecting right and left cerebral hemispheres and transmitting neural messages between them
What is the calcarine sulcus
Primary visual cortex
How many lobes of the brain are there
5
What are the lobes of the brain
frontal parietal temporal occipital insular
Where is the insular lobe located
usually hidden deep in lateral sulcus
what are the meningeal layers
dura mater
arachnoid mater
pia mater
How many layers of dura are there
2
what space is found under the arachnoid mater and what is found inside
subarachnoid space contains CSF
describe the path of CSF and ventricles
lateral ventricles interventricular foramen of monro 3rd ventricle cerebral aqueduct 4th ventricle foramen of magendie and luschka
what is a nucleus
collection of soma in the CNS
What is a ganglion
collection of soma in the PNS
what is a tract
collection of axons surrounded by connective tissue and blood vessels in the CNS
what is a nerve
collection of axons surrounded by connective tissue and blood vessels in the PNS
what modalities can a nerve be
somatic sensory somatic motor visceral afferent sympathetic parasympathetic
what modality do multipolar neurons tend to be and where is their soma found
motor
soma found in CNS
What modality do unipolar neurons tend to be and where is their soma found
sensory
soma found in PNS in dorsal root ganglion
How many pairs of spinal nerves are there and how many of each are cervical, thoracic, lumbar, sacral and coccygeal
31 pairs C1-8 T1-12 L1-5 S1-5 Co 1
Where are spinal nerves only found
intervertebral foramina
What modality are the posterior root(lets)
sensory only
What modality are the anterior root(lets)
motor only
What modality are the spinal nerves and rami
mixed sensory and motor
What is a dermatome
area of skin supplied with sensory innervation by a single spinal nerve
what is a myotome
skeletal muscles with motor innervation by a single spinal nerve
are myotomes always deep to dermatomes
sometimes, eg:
T2-12 yes
C3,4,5 no
What are nerve plexuses and give examples
nerve plexus = joining of ANTERIOR rami of adjacent spinal nerves cervical C1-4 brachial C5-T1 lumbar L1-4 sacral L5-S4
where are the cell bodies of sympathetic nerves found
lateral horn of the spinal cord
What can impaired sympathetic innervation to the head and neck cause
Horner’s syndrome
miosis
ptosis
anhydrosis
What is the epidural space
Space between the bone and dura mater in the spinal cord only
How many lobes does the cerebellum have
3
anterior
posterior
floculonodular
How is the cerebellum attached to the brainstem
via peduncles
superior, middle and inferior
What are gyri called in the cerebellum
folia
name the 4 deep cerebellar nuclei
dentate
emboliform
globose
fastigi
how many layers make up the cerebellar cortex
3
molecular
Purkinje
Granule cell
where do fibres arriving (afferent) at the cerebellum come from
spinal cord
cerebral cortex
vestibular apparatus
Where do efferent projection from the cerebellum go through
Purkinje cell layer
Cerebellar hemispheres control the contralateral side of the body, true or false
FALSE
cerebellar hemispheres control ipsilateral side of the body
cerebral hemispheres control contralateral side of the body
What is the arterial blood supply to the cerebellum
superior cerebellar artery
anterior inferior cerebellar artery AICA
posterior inferior cerebellar artery PICA
What are the basal ganglia
group of subcortical nuclei
a number of masses of grey matter near the base of each cerebral hemisphere
What are the functions of the basal ganglia
facilitate purposeful movement
inhibit unwanted movement
role in posture and muscle tone
What structures make up the basal ganglia
caudate nucleus putamen globus pallidus subthalamic nucleus substantia nigra
What makes up the lenticular nucleus
putamen
globus pallidus
What makes up the striatum
caudate nucleus
putamen
What makes up the corpus striatum
caudate nucleus
putamen
globus pallidus
What is special about the substantia nigra
it produces a black pigment as a byproduct of producing dopamine
What pathways exist in the basal ganglia
direct
indirect
What is the function of the direct pathway
enhances outflow of thalamus and helps to initiate movement essentially by freeing the thalamus from inhibitory effects
What is the function of the indirect pathway
inhibits outflow of thalamus and dampens down activity resulting in increased suppression of unwanted movements
What does damage to the basal ganglia result in
changes in muscle tone
dyskinesias = abnormal involuntary movements
What are the groups of back muscles
extrinsic and intrinsic
What is the function of the extrinsic back muscles
move upper arms
attach back to pectoral girdle
What are the extrinsic back muscles called
rhomboid major and minor
levator scapulae
trapezius
latissimus dorsi
What does the anterior rami of cervical nerve innervate
rhomboids
levator scapulae
latissimus dorsi
What innervates the trapezius
spinal accessory nerve / CN XI
What is the function of the intrinsic back muscles
maintain posture and move the spine
muscles are entirely within back
what are the intrinsic back muscles
erector spinae
transversopinalis
describe the erector spinae muscles
superficial
3 vertical muscle groups
describe the transversospinalis muscle
deep
located between the transverse and spinous processes
what muscle is commonly suspected of being the cause of lower back pain
erector spinae
What is the nerve supply of the intrinsic back muscles
posterior rami branches of cervical, thoracic and lumbar spine
What back muscles cause spine extension
intrinsic muscles: erector spinae and transversospinalis
What back muscles cause spine flexion
psoas major and rectus abdominus
How many vertebrae are there in total in the human spine
33 C1-7 T1-12 L1-5 5 fused sacral 4 fused coccygeal
Where can spinal nerves be found
intervertebral foramen
list the ligaments of the spine
supraspinous interspinous ligamentum flavum posterior longitudinal ligament anterior longitudinal ligament
Anterior longitudinal ligament is (broad + strong / thin and weak) and is (anterior/posterior) to the vertebral bodies and prevents over (extension/flexion) of the spine
broad + strong
anterior
extension
List common features of the c-spine vertebrae
transverse foramen
bifid spinous process
triangular shaped vertebral foramen
what is the C1 vertebrae called, describe its features
atlas
no body or spinous process
has posterior and anterior arches instead
what is the C2 vertebrae called, describe its features
axis
odontoid process
Which vertebrae has the first palpable spinous process
C7
You can still see the posterior arch on c-spine xray, true or false
TRUE
at which level does the spinal cord end and what is the name given
L1/2
conus medullaris
What is the cauda equina
all the spinal nerve roots from L2 onwards
What modalities are present in the body wall/soma
General somatic afferent = sensory
General somatic efferent = motor
General visceral efferent = sympathetic motor
spinal reflexes
There are no parasympathetic fibres in the body wall/soma, true or false
TRUE
How can you test each spinal nerve segment’s sensory function
dermatomes
How can you test each spinal nerve segment’s motor function
myotomes
How can you test each spinal nerve segment’s sensory and motor function
spinal cord reflexes
C1 spinal nerve is sensory/motor?
MOTOR ONLY
Which nerve provides sensation to the face
CN V 1,2+3
What does dermatomal testing allow you to check the integrity of
spinal nerve
posterior root and rootlets
What is the named nerve cutaneous innervation of the neck
Hint: Little Goats Tread Softly
Lesser occipital
Greater auricular
Transverse cervical
Supraclavicular
what are the layers of the scalp
SCALP
skin connective tissue aponeurosis loose connective tissue pericranium
what is the blood supply of the scalp
ECA and ICA anastamoses
What is special about the pterion
it is a H shaped feature and it is the thinnest part of the skull
the middle meningeal artery runs underneath it
Which meningeal layer has sensory supply from the trigeminal nerve
dura mater
Which meningeal layer has arachnoid granulations and what are these
arachnoid mater
reabsorb CSF into dural venous sinuses
How many layers of dura mater are there in the brain
2 - cranial and periosteal
What lies inside the 2 layers of dura mater
the 2 layers separate at certain points where dural venous sinuses arise
what structures does the dura mater form
falx cerebri and tentorium cerebelli and diaphragm sellae
Where is the circle of willis found
within the subarachnoid space
Between which layers is the subarachnoid space found
arachnoid and pia mater
at which spinal level does the subarachnoid space close
S2
Where is the middle meningeal artery found
between bine and dura mater
Where does extra dural haemorrhage happen
between bone and dura mater
Where does subdural haemorrhage happen
between dura and arachnoid mater from torn cerebral veins
where does subarachnoid haemorrhage happen
in subarachnoid space
