USAHS Neuroscience Exam 3 Questions
and Answers
Essential functions: - Answer- location for cranial nerve nuclei
connection to levels of consciousness
cerebellar circuits
regulate muscle tone
posture
cardiac responses
Rostral limit= - Answer- midbrain-diencephalic junction
Midbrain-pons= - Answer- Ponto mesencephalic junction
Pons-medulla= - Answer- pontomedullary
Caudal limit= - Answer- corticomedullary junction
Dorsal= - Answer- tectum roof = superior and inferior colliculi
Ventral= - Answer- cerebral peduncles (interpeduncular fossa in center separates the two peduncles) and pyramidal decussation
Lateral= - Answer- pons: limited by 4th ventricle, superior middle inferior cerebellar peduncles (white matter tracts and connections of info from pons ot cerebellum)
Olfactory- - Answer- cribriform plate
Optic nerve- - Answer- optic canal
Oculomotor, trochlear, abducens, trigeminal V1- - Answer- superior orbital fissure
Trochlear nerve is only CN that is - Answer- dorsal/posterior
Trigeminal V2- - Answer- foramen rotundum
Trigeminal V3- - Answer- foramen ovale
Facial- - Answer- internal auditory canal to enter auditory canal then exits skull via stylomastoid foramen Vestibulocochlear- - Answer- internal auditory canal to enter auditory canal
Glossopharyngeal, vagus, spinal accessory- - Answer- jugular foramen
CN9: - Answer- Exits brainstem as several rootlets along the upper ventrolateral medulla bw inferior olive and inferior cerebellar peduncle
CN10: - Answer- Exits ventrolateral medulla as several rootlets just below CN9 bw inferior olive and inferior cerebellar peduncle
CN11: - Answer- Nerve rootlets leave nucleus and exit lateral aspect of SC bw dorsal and ventral roots just dorsal to the dentate ligament and ascend through foramen magnum
Hypo- hypoglossal foramen - Answer- Exits ventral medulla as multiple rootlets bw pyramid and inferior olivary nucleus in hypoglossal foramen
Open medulla is
closed medulla is - Answer- dorsal/posterior with the four dots;
·ventral/anterior and will show the big belly of pons and pyramids with olives on either side
Midbrain: - Answer- Inferior colliculi is hearing; superior colliculi is vision
retinal blood supply= - Answer- ophthalmic artery
§ ophthalmic artery branches into retinal artery
§ blockages: emboli, stenosis, vasculitis
retinal artery - Answer- 2 main branches: Superior, Inferior
Occlusion causes an altitudinal scotoma in one eye
· Ex- Pt would lose vision in lower half of R eye caused by occlusion of superior branch of R retinal artery in R eye
Amaurosis fugax- transient occlusion of superior or inferior branch of retinal artery
· Vision "browning out" in either upper or lower part
· Lasts ~10 min
· Common cause: ipsilateral ICA stenosis (like a TIA)
· At risk for retinal or cerebral infarct
Optic nerves, optic chiasm, optic tracts receive blood supply from numerous small branches of ACA and MCA - Answer- Rarely see significant infarcts
and Answers
Essential functions: - Answer- location for cranial nerve nuclei
connection to levels of consciousness
cerebellar circuits
regulate muscle tone
posture
cardiac responses
Rostral limit= - Answer- midbrain-diencephalic junction
Midbrain-pons= - Answer- Ponto mesencephalic junction
Pons-medulla= - Answer- pontomedullary
Caudal limit= - Answer- corticomedullary junction
Dorsal= - Answer- tectum roof = superior and inferior colliculi
Ventral= - Answer- cerebral peduncles (interpeduncular fossa in center separates the two peduncles) and pyramidal decussation
Lateral= - Answer- pons: limited by 4th ventricle, superior middle inferior cerebellar peduncles (white matter tracts and connections of info from pons ot cerebellum)
Olfactory- - Answer- cribriform plate
Optic nerve- - Answer- optic canal
Oculomotor, trochlear, abducens, trigeminal V1- - Answer- superior orbital fissure
Trochlear nerve is only CN that is - Answer- dorsal/posterior
Trigeminal V2- - Answer- foramen rotundum
Trigeminal V3- - Answer- foramen ovale
Facial- - Answer- internal auditory canal to enter auditory canal then exits skull via stylomastoid foramen Vestibulocochlear- - Answer- internal auditory canal to enter auditory canal
Glossopharyngeal, vagus, spinal accessory- - Answer- jugular foramen
CN9: - Answer- Exits brainstem as several rootlets along the upper ventrolateral medulla bw inferior olive and inferior cerebellar peduncle
CN10: - Answer- Exits ventrolateral medulla as several rootlets just below CN9 bw inferior olive and inferior cerebellar peduncle
CN11: - Answer- Nerve rootlets leave nucleus and exit lateral aspect of SC bw dorsal and ventral roots just dorsal to the dentate ligament and ascend through foramen magnum
Hypo- hypoglossal foramen - Answer- Exits ventral medulla as multiple rootlets bw pyramid and inferior olivary nucleus in hypoglossal foramen
Open medulla is
closed medulla is - Answer- dorsal/posterior with the four dots;
·ventral/anterior and will show the big belly of pons and pyramids with olives on either side
Midbrain: - Answer- Inferior colliculi is hearing; superior colliculi is vision
retinal blood supply= - Answer- ophthalmic artery
§ ophthalmic artery branches into retinal artery
§ blockages: emboli, stenosis, vasculitis
retinal artery - Answer- 2 main branches: Superior, Inferior
Occlusion causes an altitudinal scotoma in one eye
· Ex- Pt would lose vision in lower half of R eye caused by occlusion of superior branch of R retinal artery in R eye
Amaurosis fugax- transient occlusion of superior or inferior branch of retinal artery
· Vision "browning out" in either upper or lower part
· Lasts ~10 min
· Common cause: ipsilateral ICA stenosis (like a TIA)
· At risk for retinal or cerebral infarct
Optic nerves, optic chiasm, optic tracts receive blood supply from numerous small branches of ACA and MCA - Answer- Rarely see significant infarcts
