Neuroanatomy Flashcards
what does the brainstem consist of?
Midbrain, Pons and Medulla Oblongata
what does the diencephalon consist of?
Thalamus, Hypothalamus
Name the 4 types of glial cell and their functions
Astrocytes- Support, Communicate with endothelial cells to maintain blood brain barrier
Oligodendrocytes- Produce Myelin (found in CNS, Schwann cells found in PNS)
Microglial Cells- Macrophages
Ependymal Cells- Lines cavities, Ciliated
what is the term for a deep groove, shallow groove and lump on the brain and cerebellum?
fissure,
Sulcus
Gyrus- Brain
Folium- Cerebellum
calcarine sulcus- vision
cingulate sulcus- suffering
what are the landmarks demarcating the frontal lobe?
the central and lateral sulci
what’s the name of the 5th lobe and what is its function?
Insular lobe or insula
Co-ordinates and pain
what is the enteric nervous system called?
myenteric plexus
where are the cavernous sinuses located?
Lateral to the sella turcica
what are the two different types of neuron and what is the difference between them?
Multipolar (ANS and Motor)- cell body found in CNS- multiple proccesses
Unipolar (sensory)- cell body found in PNS (dorsal route ganglion)
where are spinal nerves located?
only within the intervertebral foramina
describe the dermatomes
name the 4 plexi, where they inervate and what spinal nerves contribute to them
- Cervical plexus
- C1-C4 anterior rami
- Posterior scalp, neck wall …..and diaphragm
- Brachial plexus
- C5-T1 anterior rami
- Upper limb
- Lumbar plexus
- L1-L4 anterior rami
- Lower limb
- Sacral plexus
- L5-S4 anterior rami
- Lower limb, gluteal region and perineum
which spinal nerves make up the sympathetic chain?
T1-L2
how would you recognise a segment of the spinal cord running from T1 to L2
Lateral horns
describe the sympathetic outflow via the paravertebral ganglion
describe how sympathetic outflow reaches organs
for heart and lungs spinal presynaptic axons synapse at paravertebral ganglions. Postsynaptic axons continue in cordiopulmonary spanchnic nerves
For abdominal organs. presynaptic axons synapse in prevertebral ganglia.
For adrenal medulla the presynaptic axons synapse directly to it
what are the facial signs and causes of horner’s syndrome?
-Facial signs include:
- ipsilateral ptosis: drooping of the upper eyelid
due to lack of sympathetic innervation of the
smooth muscle within levator palpebrae
superioris
- ipsilateral miosis (pinpoint pupil) due to lack of
sympathetic innervation of the dilator pupillae
- reduced sweating of the ipsilateral facial skin
due to lack of sympathetic innervation of skin
sweat glands
- Causes of compression of the cervical parts of the sympathetic trunk:
- root of neck trauma (transection or haematoma)
- arch of aorta dissection
- internal jugular vein engorgement
- goitre
- deep cervical node metastases
- direct spread from lung apex malignancy
(pancoast tumour)
describe parasympathetic outflow
-Parasympathetic ganglia in head – to lacrimal gland (facial nerve) and salivary glands (parotid glossopharyngeal and facial for other 2)
-
-Vagus nerve supplies organs of the neck, chest and abdomen as far as the mid-gut
-
-Sacral spinal nerves ‘carry’ parasympathetic axons to the hindgut, pelvis and perineum
-
The spinal cord terminates in a tapered cone-shape called the …… which in turn, continues as a thin connective tissue cord called the …… which is anchored to the dorsum of the coccyx.
conus medullaris
filum terminale
The spinal cord is suspended in the canal by a ribbon of tissue on the lateral aspects of the cord called the ……. This ligament is formed of pial and arachnoid tissue and attaches to the dura at points along the length of the cord.
denticulate ligament
name the four comlumns in the spinal cord
lateral, posterior and anterior
name the sulcus and fissure found on the spinal cord
dorsal median sulcus and septum
ventral median fissure
describe the arterial supply of the spine
A. Three major longitudinal arteries: one anterior and two posterior that originate from the vertebral arteries. These run the length of the cord.
B. Segmental arteries derived from vertebral, intercostal and lumbar arteries.
C. Radicular arteries that travel along the dorsal and ventral roots.
Unlike the dura in the cranial cavity, which is attached to the periosteum, in the spinal canal there is a space between the dura and the bone, termed the ….., which contains adipose tissue and the anterior and posterior epidural venus plexuses. This space is utilized in epidural anaesethesia.
epidural space
where is the primary somatosensory cortex located?
just posterior to the central sulcus in the parietal lobe
post central gyrus
What is the name of the system that supplies fine touch and concious proprioception (particularly from the upper limb)
Dorsal Column/ Medial Lemniscus Sytem
how many nerves are there in the dorsal column/medial lemniscus system? Where do they synapse? Where do they cross?
what are the two components of the dorsal column (dorsal funiculus)?
Fasciculus Gracilis (fine touch and concious proprioception from leg)
Fasciculus Cuneatus (from upper limb)
what is the name of the tract that carries pain, temperature and deep pressure?
where does it cross
spinothalamic tract
crosses segmentally
where is the primary motor cortex?
precentral gyrus
Which tract allows fine, precise movement, particularly of distal limb muscles (e.g. digits).
Corticospinal tract
Tract forms visible ridges referred to as the ‘pyramids’ on the anterior surface of the medulla, so also called the pyramidal tract. About 85% of fibres cross in the caudal medulla at the decussation of the pyramids.
Crossed fibres form the Lateral CST.
Uncrossed fibres form the Ventral CST, which cross segmentally.
what is docorticate posturing and what causes it?
hyperflexion of the upper limbs caused by a CVA in internal capsule resulting in a lack of descending control
There are a number of motor systems outside of the pyramidal tract and these are often referred to collectively as the……
“extrapyramidal system”
The reticulospinal tract has variety of functions including infuencing volantary movements.
where is the reticular formation found?
Where are fibres influencing extension and flexion located?
Core of brainstem
In general: Fibres originating in pons facilitate extensor movements and inhibit flexor movements, while those originating in the medulla do the opposite.
which tract is involved in the process of stopping a fall
vestibulo spinal tract
input into “antigravity muscles”
fibres originate vestibular nuclei of pons and medulla, which in turn recieve inout from vestibular apparatus and cerebellum
The ….. is thought to play an important role in patients exhibiting decerebrate rigidity and paraplegia in extension. Lesions of the brainstem at or below the midbrain can result in a lack of descending cortical control of this tract (plus others). This leads to domination of extensor muscle tone and hyperextended spastic paralysis.
vestibulospinal tract
give a definition for the back
a part of the soma (body wall)
anatomically it is:
the posterior aspect of the trunk
(trunk = chest + abdomen + pelvis + back)
lies inferior to the neck
lies superior to the gluteal region
is attached to the upper limbs
is attached to the lower limbs
composed mainly of skeletal muscle &
bone
name the two main groups of intrinsic back muscles
Erector spinae (superficial)
Transversospinalis (deep)
which are the only vertebrae not to have discs?
-between all vertebrae except C1-C2 and the fused sacrum/coccyx
Fescribe all the ligaments attatched to the spinal cord
Ligamentum flavum
-short
-connect adjacent laminae posterior to spinal cord
-
-posterior longitudinal ligament
-narrow, weak
-attaches to posterior aspects of all vertebral bodies and intervertebral discs
-less support for disc
-prevents over-flexion of spine-anterior longitudinal ligament
-broad, strong
-attaches to anterior aspects of all vertebral bodies and intervertebral discs
-stronger support for disc
-prevents over-extension of spine
-
- supraspinous ligament
- short
- connects tips of spinous processes
- strong, fibrous-
- interspinous ligament
- short
- connect superior and inferior surfaces of adjacent spinous processes
- weak, membranous
what feature is unique to cervical vertibrae?
- All have a foramen in each transverse process
- transverse foramen
- passage of vertebral arteries
which joints main movementes are nodding and shaking the head?
nodding- atlanto-occipital join
shaking- atlanto-axial joint
in caudal anaesthesia local anaesthetic is injected into the …… to anaesthetise the sacral spinal nerve roots of the cauda equina
sacral hiatus
at what level does the spinal cord end?
L2
Outline the points at which you examine the spinal nerves dermatomes
C2 – back of scalp & Adam’s apple
C3 – back of neck & jugular notch
C4 – clavicle & shoulder tip
C5 – “badge patch”
C6 - thumb
C7 – middle finger
C8 – little finger
T1 – medial forearm
T2 – medial arm & sternal angle
T3
T4 – male nipple
T5
T6
T7
T8 – xiphoid process
T9
T10 - umbilicus
T11
T12 – pubic symphysis
L1 – groin (“hands in pockets”)
L2 – anterior thigh
L3 – anterior knee
L4 – medial malleolus
L5 – dorsum of foot
S1 - heel
S2 – posterior knee
S3 - buttock
S4 - perineum
S5 – perianal skin
outline the lobes of the cerebellum
name the basal ganglia
where is the substantia nigra found?
photo shows axial section of midbrain
highlight the key sensory points
what are the named nerves of cutaneous innervation of the neck?
what is the named nerve cutaneous innervation of the trunk?
describe the named nerve cutaneous innervation of the back
describe the named nerve cutaneous innervation of the skin
describe the named nerve cutaneous innervation of the lower limb
where is the primary olfactory area?
where are the motor and sensory areas within the brainstem?
where are the inf/sup colliculus?
the middle cerebellar peduncle?
and the floor of the 4th ventricle?
describe the solitary nucleus
which nerves originate from it?
what are the two segments?
what is the most destinctive feature of the medulla?
the olivary nucleus
describe the path that fibres take after leaving the cochlea
input is bilateral
Superior olivary nucleus and nucleus of lateral lemniscus are important in sound localization and as relays for stapedial and tensor tympany reflexes.
Name: Q,N,L,F,H,G
Q = CN VIII
N = 4th Ventricle
L= Middle cerebellar peduncle
F = Inferior colliculus
H = Medial geniculate nucleus
G = Inferior brachium
where is Broca’s Area?
Wernicke’s Area?
and the primary auditory cortex?
describe the visual pathway
where is the primary visual cortex?
where do the visual fields lie in the visual cortex?
outline the different regions of trigeminal nerve innervation
describe the trigeminal nerve’s motor innervation
list the functions of the glossopharyngeal nerve
what are the origins and insertions of the spinal accessory nerve
describe the arteries that form the circle of willis
describe the different types of bleeding within the cranial cavity
