Neuroanatomy Flashcards
Where does the cerebellum sit?
Posterior fossa
What are the 3 layers of the meninges?
Dura mater
Arachnoid mater
Pia mater
Which layer of the meninges absorbs CSF? How?
Arachnoid mater via arachnoid granulations
What is the most commonly damaged artery with a fracture to the temple of the head?
Middle meningeal artery
What is the most commonly affected artery in an epidural hematoma?
Middle meningeal artery
Separates the left and right cerebral hemispheres
Falx cerebri
Separates the cerebellar hemispheres
Falx cerebelli
Separates occipital lobes from cerebellum
Tentorium cerebelli
What are the main venous sinuses of the head?
Superior sagittal sinus Inferior sagittal sinus Straight sinus Transverse sinuses Sigmoid sinuses Occipital sinus Cavernous sinus
Which sinus is most likely to be involved in the spread of infection? Why?
Cavernous sinus —> it also drains the face
Which structure runs among the veins of the cavernous sinus?
Internal carotid artery
CNs III-VI
What is the most common cause of a subdural hematoma?
Trauma/ damage from rotational velocity —> tear of a cerebral vein (between dura mater and arachnoid mater)
*bleeds slowly - “awake and dead”
Responsible for voluntary motor functions, planning, mood, smell, emotions, and social judgement
Frontal lobe
Receives and integrates sensory information
Parietal lobe
Visual center of the brain
Occipital lobe
Areas for hearing, smell, learning, memory, and emotional behavior
Temporal lobe
What structures are located in the anterior cranial fossa?
Frontal lobes
Olfactory bulbs and tracts
What structures are located in the middle cranial fossa?
Temporal lobes
Pituitary gland
What are the parts of the brain stem?
Midbrain, pons, medulla oblongata
Keeps you awake and focuses your attention to certain stimuli; problem solving; located in brain stem
Reticular activating system
Over half of the brain’s neurons are located where?
Cerebellum
What structures are located in the posterior cranial fossa?
Brain stem
Cerebellum
What is the function of CSF?
Buoyancy of the brain
Protective cushioning
The result of overproduction, flow obstruction, or malabsorption of CSF
Hydrocephalus
What can cause hydrocephalus?
Damage to the arachnoid granulations
Stenosis of duct
Where do the vertebral arteries travel in the spine?
Transverse foramina of the vertebrae
The vertebral arteries come together to form what?
Basilar artery
What arteries make up the circle of Willis?
Anterior cerebral arteries Anterior communicating arteries Middle cerebral arteries Posterior communicating arteries Posterior cerebral arteries Basilar artery
Infarct of which arteries can lead to Wallenberg’s Syndrome (loss of balance, coordination, sensation of the face and body, sense of body position and midline, vocal cord function, and eye movement coordination)?
Posterior inferior cerebellar arteries (PICA)
What is the most common site of aneurysms in the circle of Willis?
Anterior communicating arteries
Where does the spinal cord end?
Between T12-L3
Which the cervical and lumbosacral enlargements give rise to what?
Cervical - brachial plexus
Lumbosacral - lumbar/sacral plexuses
Where does the dural sac end?
S2
Where is CSF located?
Subarachnoid space
What is the best place to do a spinal tap?
Between L3 and L4 into lumbar cistern
Sheet of pia mater that suspends spinal cord in the dural sac
Denticulate ligaments
End of the spinal cord (location)
Conus medullaris - L1/L2
Located in the lumbar cistern
Cauda equina
What structures pass over the cribiform plate?
Olfactory nerves (CN I)
What structures pass through the optic canal?
Optic nerve (CN II) Ophthalmic artery
What structures pass through the superior orbital fissure?
Oculomotor nerve (CN III) Trochlear nerve (CN IV) Ophthalmic nerve (CN V1) Abducent nerve (CN VI) Ophthalmic veins
What structures pass through the foramen rotundum?
Maxillary nerve (CN V2)
What structures pass through the foramen ovale?
Mandibular nerve (CN V3)
What structures pass through the foramen spinosum?
Middle meningeal artery and vein
What structures pass through the foramen lacerum?
Internal carotid artery
What structures pass through the internal acoustic meatus?
Facial nerve (CN VII) Vestibulocochlear nerve (CN VIII)
What structures pass through the jugular foramen?
Glossopharyngeal nerve (CN IX)
Vagus nerve (CN X)
Spinal accessory nerve (CN XI)
Internal jugular vein
What structures pass through the hypoglossal canal?
Hypoglossal nerve (CN XII)
What structures pass through the foramen magnum?
Medulla
Meninges
Spinal root of CN XI
Vertebral arteries
What is CN I and what does it do?
Olfactory nerve
Olfactory information
What is CN II and what does it do?
Optic
Visual information
What is CN III and what does it do?
Oculomotor
Innervates most eye muscles
What CN contribute to somatic motor pathways?
Oculomotor
Trochlear
Abducent
Hypoglossal
What is CN IV and what does it do?
Trochlear
Superior oblique eye muscle
What is CN V and what does it do?
Trigeminal
Chewing muscles + facial sensation
What is CN VI and what does it do?
Abducent
Lateral rectus of the eye
What is CN VII and what does it do?
Facial
Facial muscles + taste ant 2/3 (chorda tympani)+ eye lid + back of ear _ salivary and lacromal glands + nasal/palatal glands
What is CN VIII and what does it do?
Vestibulocochlear
Hearing + balance
What is CN IX and what does it do?
Glossopharyngeal
Salivation + 1/3 post taste
What is CN X and what does it do?
Vagus
Heart, gut, midgut + swallowing
A lesion in what cranial nerve would cause a deviation in the uvula? In which direction?
Vagus, deviates away from the lesion
What is CN XI and what does it do?
Spinal accessory
SCM and trapezius
What is CN XII and what does it do?
Hypoglossal
Tongue movements
What nerve developed in the first branchial arch?
Trigeminal V3
What nerve developed in the second branchial arch?
Facial nerve
What nerve developed in the third branchial arch?
Glossopharyngeal nerve
What nerve developed in the fourth branchial arch?
Vagus
What nerve developed in the sixth branchial arch?
Spinal accessory
What nucleus does CNV3 originate from?
Trigeminal nucleus (branchiomotor)
What nucleus does CN VII originate from?
Facial nucleus (branchiomotor) Superior salivary nucleus (parasympathetic)
What nucleus does CN IX originate from?
Nucleus ambiguous (branchiomotor) Inferior salivary (parasympathetic)
What nucleus does CN X originate from?
Nucleus ambiguus (branciomotor) Dorsal motor nucleus (parasympathetic)
Where does CN XI originate from?
Cervical accessory nucleus (branchiomotor)
What nucleus does CN XII originate from?
Hypoglossal nucleus (somatic motor)
What nucleus does CN III originate from?
Edinger-westphal (parasymapthetic) Oculomotor nucleus (somatic motor)
What nucleus does CNIV originate from?
Troachlear (motor)
What ganglion does CN III project to and or what action?
Ciliary ganglion (parasympathetic) - pupillary/cilliary response
What ganglion does CN VII project to for which action?
Pterygopalatine ganglion (parasymapthetic) - lacromal gland for tears Submandibular gland (parasymapthetic) - submandibular/sublingual glands for salivation
What ganglion does CN IX project to for which action?
Otic ganglion (parasymapthetics) —> parotid gland for salivation
What ganglion does CN X project to for which action?
Cardiac/mesenteric ganglion (parasympathetic) —> heart, foregut, gut parasympathetics
What are the two organs/nerves supplied by sympathetic motor neurons?
Eye and tongue:
Oculomotor
Trochlear
Abducent
Hypoglossal
Where does the trigeminal nerve travel/synapse to to relay TOUCH sensory information? What kind of touch information?
Trigeminal ganglion —> trigeminal sensory nuclei
Face
What are the 3 trigeminal sensory nuclei and what information do the each receive?
Mesencephalic - proprioception
Principle sensory - discriminative touch
Spinal trigeminal - pain + temperature
Where does the glossopgaryngeal nerve travel/synapse to to relay TOUCH sensory information? What kind of touch information?
Superior glossopharyngeal ganglion —> trigeminal sensory nuclei
Oropharynx
Where does the vagus nerve travel/synapse to to relay TOUCH sensory information? What kind of touch information?
Jugular ganglion —> trigeminal sensory nuclei
Where does the facial nerve travel/synapse to to relay TOUCH sensory information? What kind of touch information?
Geniculate ganglion —> trigeminal nuclei
Back of ears
Where does the facial nerve travel/synapse to to relay TASTE sensory information? What kind of taste information?
Geniculate ganglion —> rostral nucleus solitarius
Anterior 1/3 of tongue
Where does the glossopharyngeal nerve travel/synapse to to relay TASTE sensory information? What kind of taste information?
Petrosal ganglion —> rostral nucleus solitarius
Posterior 1/3 of tongue
Where does the vestibulocochlear nerve travel/synapse to to relay HEARING/BALANCE sensory information?
Straight to the cochlear and vestibular nuceli
Where does the vagus nerve travel/synapse to to relay cardiac and gut sensory information as well as pain?
Inferior vagaries ganglion —> Caudal nucleus solitarius
Where does the DCML tract travel in the spinal cord?
Posterior/dorsal column between the dorsal horns
Cervical portions are most medial to the horns
Decussates at medulla
Where does the corticospinal tract travel in the spinal cord?
Posterior: Immediately anterior to the dorsal horn
Cervical portions are most medial to the horns
Decussates at medulla
Where does the spinothalamic tract travel in the spinal cord?
Anterior: lateral to the ventral horn
Cervical portions are most medial to the horns
Decussates at level of the spinal cord
What structures run through the cavernous sinus?
CN III, IV, V1, V2, VI
Internal carotid
What would damage to the facial nerve do?
Produces sagging facial muscles and disturbed sense of taste
The motor branch of the facial nerve exits where to reach the muscles of mastecation?
Stylomastoid foramen
Nerve carrying parasymapthetics (from facial nerve) to the lacromal gland
Greater petrosal nerve
Nerve carrying taste and parasymapthetics to salivary glands; runs across tympanic membrane and piggy backs on V3
Chorda tympani
Damage to the facial nerve as it exits stylomastoid foramen
Bell’s palsy
What are the signs of Bell’s palsy?
Sagging eyelid, drooping mouth, paralysis of muscles of facial expression
If one hypoglossal nerve is damaged, the tongue deviates to which side?
Tongue deviates toward injured side
What would a lesion of the CN XI result in?
Trapezius atrophy; weakness in shrugging, impairment of rotational movements of neck (SCM)
Which muscle is responsible for eye opening?
Levator palpebrae superioris
Which muscle is responsible for pupil constriction?
Circular muscle
Which muscle is responsible for pupil dilation and focusing?
Ciliary muscle
What are the symptoms of oculomotor palsy? What nerve is damaged?
Ptosis of superior eye lid
Eyeball pointing down and out
No pupillary reflex
No accommodation
Damage to the trochlear nerve causes what?
Double vision and inability to rotate eye inferolaterally
Damage to the abducens nerve causes what?
Inability to rotate eye laterally; eye rests medially
Which nerve is easily stretch or compressed with increased intercranial pressure?
Abducens — bends sharply over petrosal part of temporal bone
Loss of smell
Ansomia
What would the symptoms of a lower motor neuron lesion?
Flaccid Decreased tone Decreased muscle stretch reflexes Profound muscle atrophy Fasciculations present Sensory disturbances
What would the symptoms of a upper motor neuron lesion?
Spasticity Increased tone Increased muscle stretch reflexes Minimal muscle atrophy Fasciculations present Sensory disturbances
Transparent mucous membrane
Conjunctiva
Covers sclera and contains blood vessels
Bulbar conjunctiva
Space bound by palpebral and bulbar conjunctiva
Conjunctival sac
Names the structures deep to the eye lid
Orbicularis oculi
Superior and inferior tarsi (connective tissue)
Tarsal glands (within tarsi; lubricate eyelid
Name the path way of tears
Lacrimal gland —> lacrimal duct —>lacrimal canaliculi (corner of eye) —> lacrimal lake —> lacrimal sac —> nasolacrimal duct —> nasal cavity
Muscle that elevates the eyelid
Levator palpebrae superioris
Action of the superior oblique
Look down and out
Action of the inferior oblique
look up and out
What are the 3 layers of the eye and what’s in them?
Fibrous: sclera and cornea
Vascular: choroid, ciliary body, iris
Inner: retina
White of the eye; dense layer of connective tissue
Sclera
Clear anterior surface of the eye continuous with sclera
Cornea
Dense vascular bed of the eye
Choroid
Controls contraction of lens
Ciliary body
Thin contractile diaphragm with pupil; transmits light
Iris
Parasymapthetic muscle of the ciliary body; constricts
Sphincter pupillae muscle
Sympathetic muscle of the ciliary body; dilates
Dilator pupillae muscle
Posterior part of the retina where light is focused
Ocular fundus
Blind spot of the eye
Optic disc
The area of most acute vision; many cones
Fovea centralis
Yellow spot, surrounds fovea
Macula lutea
What is the blood supply to the eyes?
Ophthalmic artery (off internal carotid) Central retinal artery (off ophthalmic artery)
Bones of the middle ear
Malleus, incus, stapes
What are the to muscles protecting the tympanic membrane from loudness?
Tensor tympani
Stapedius
Connects tympanic cavity to nasopharynx
Pharyngotympanic tube
Opens up the pharyngotympanic tube
Levator veli palatini
Tensor veli palatini
What 3 nerves contribute to inner ear sensation?
CN V3 - tensor tympani
CN VII - stapedius muscle
CN IX - tympanic membrane/plexus
CN VIII - cochlea and semilunar canals
