Neuroanatomy Flashcards
How many pairs of cranial nerves are there?
12
How many pairs of spinal nerves are there?
31
Where does the transition from CNS to PNS occur?
As the nerve roots leave/enter the spinal cord
*What are the 3 embryological swellings of the brain and what do they go on to become?
Prosencephalon, Mesencephalon and Myelencephalon
What is the main functions of astrocytes?
Physical support, maintain extracellular environment and form BBB
What is the function of oligodendrocytes?
Produce myelin in the CNS (Schwann cells in the PNS)
What is the function of microglia?
Immune cells of the brain (antigen presenting and phagocytic)
What is the function of ependymal cells?
Line the ventricles and helps in the production of CSF
Which way round is the grey/white matter in the brain and spinal cord?
Grey is on the outside in the brain, white is on the outside in the cord
What separates the frontal and parietal lobes?
Central sulcus
What are the boundaries of the parietal lobe?
Central sulcus anteriorly, pre-occipital sulcus to preoccipital notch (bump formed by petrous bone) posteriorly and lateral sulcus below
What is the hidden 5th lobe?
Insular lobe - deep in the lateral fissure (part of the limbic system)
*What connects the lateral ventricles to the 3rd?
Interventricular foramen
*What connects the 3rd ventricle to the 4th?
Cerebral aqueduct
*What connects the 4th ventricle to the subarachnoid space?
2x lateral and 1x medial aperture
What is the mystery third nervous system (other than CNS and PNS) and where is it found?
Enteric NS (found in digestive system from oesophagus to anus in 2 plexuses: myenteric and submucosal)
Where does the venous blood of the dural sinuses drain into?
Internal jugular veins
What is a collection of cell bodies referred to in the CNS and PNS?
CNS = nucleus PNS = ganglion
What type of neuron are motor neurons, and where is their cell body?
Multipolar, and in the CNS
What type of neuron are sensory neurons generally, and where is their cell body?
Unipolar, and in the PNS e.g. dorsal root ganglion
What are nerves technically called in the CNS?
Tracts
In what direction are cranial nerves generally named?
Anterior to posterior, medial to lateral
Where are spinal nerves only found?
Intervertebral foramina
What is the pathway of sensory axons from the spinal nerve to spinal cord?
Nerve > posterior/dorsal root > dorsal rootlet > dorsal horn
What is the pathway of motor axons from spinal cord to spinal nerve?
Ventral/anterior horn > ventral rootlets > ventral roots > nerve
True or false: Roots are mixed
False, they are single modality
True or false: Rami are mixed
True
Where does the anterior rami go and serve?
Anterolateral structures of the trunk and limbs (e.g. all muscles except intrinsic back muscles)
Where does the posterior rami go and serve?
Posterior back structures (intrinsic back muscles + sensory)
Which spinal nerve dermatome supplies the male nipple?
T4
Which dermatome covers the umbilicus?
T10
Which dermatomes are the posterior scalp, neck and shoulder?
C2-4
Which dermatomes cover the upper limb?
C5-T1
Which dermatomes supply the lower limb?
L2-Co1
Which spinal levels have a lateral horn for sympathetic outflow?
T1-L2
What is the pathway of sympathetic outflow out of the lateral horn of the spinal cord?
Technically motor output so travels through the anterior rootlets and roots then via white rami communicans to sympathetic chain. Organs above the diaphragm synapse in these paravertebral ganglia, which organs below synapse in the prevertebral ganglia (except the adrenal gland which gets direct).
How do presynaptic parasympathetic axons leave the CNS?
Via cranial nerves III (via ciliary ganglion), VII, IX and X, and sacral spinal nerves
How do presynaptic parasympathetic axons leave the CNS?
Via cranial nerves III, VII, IX and X, and sacral spinal nerves
What are the symptoms of Horner’s Syndrome and what is the cause?
Impaired sympathetic innervation to the head and neck often due to compression of the cervical parts of the sympathetic trunk, causing: Miosis (constricted pupils), ptosis (drooping eyelid), anhydrosis (reduced sweating) and increased warmth/redness
What are the extrinsic back muscles?
Trapezius, Rhomboids, Levator scapulae, Lat dorsi
What are the intrinsic back muscles?
Erector spinae (made up of iliocostalis, longissimus and spinals) and transversospinalis (wedged between transverse and spinous processes of vertebrae)
*Label these muscles
*
What muscles cause flexion of the spine?
Psoas major and rectus abdominis (nothing to do with intrinsic muscles)
*Label the features on the vertebrae
*
*Label these vertebral features
*
*Label these vertebral ligaments
*
What is the function of the posterior and anterior longitudinal ligament?
Posterior prevents over-flexion of the spine, while anterior prevents over-extension
What are typical features of cervical vertebrae?
Transverse foramen, bifid spinous princess, very large and triangular vertebral canals