Brain Stem and Cranial Nerves Flashcards
Which cranial nerve nuclei lie medially at brain stem?
III, IV, VI, XII. (Factors of 12 except not 1 and 2).
In the organization of cranial nerve nuclei, which nuclei lie laterally?
Sensory nuclei (alar plate)
In the organization of cranial nerve nuclei, which nuclei lie medially?
Motor nuclei (basal plate).
Which nuclei are located in the midbrain?
3, 4
Which nuclei are located in the pons?
5,6,7,8
Which nuclei are located in the medulla?
9, 10, 12
Which nuclei are located in the spinal cord?
11
What is the pineal gland responsible for?
melatonin secretion, circadian rhythms
What are the superior colliculi responsible for?
Conjugate vertical gaze
What are the inferior colliculi responsible for?
Auditory
What is parinaud syndrome?
Paralysis of conjugate vertical gaze due to lesion in superior colliculi
What can cause parinuad syndrome?
Stroke, hydrocephalus, pinealoma
Which cranial nerve exits via the cribiform plate?
CN I
Which foramina are part of the middle cranial fossa through the sphenoid bone?
Optic canal Superior Orbital Fissure Foramen Rotundum Foramen Ovale Foramen spinosum
What exits via the Optic canal?
CN II, opthalmic artery, central retinal vein
What exits via the Superior Orbital Fissure?
- CN III, IV, VI. V1 of CN 5.
- Opthalmic vein, sympathetic fibers
What exits via the Foramen Rotundum?
CN V2.
What exits via the Foramen Ovale?
CN V3.
What exits via the foramen spinosum?
Middle meningeal artery
Which foramina are part of the posterior cranial fossa through the temporal or occiptal bones?
Internal auditory meatus
Jugular foramen
Hypoglossal canal
Foramen Magnum
What exits via the internal auditory meatus?
CN VII, VIII
What exits via the jugular foramen?
CN IX, X, XI, jugular vein
What exits via the hypoglossal canal?
CN XII.
What exits via the foramen magnum?
Spinal roots of CN XI, brain stem, vertebral arteries.
What are the vagal nuclei?
nucleus solitaris, nucleus ambiguous, dorsal motor nucleus
What does the Nucleus Solitarius do?
visceral Sensory info - taste, baroreceptors, gut distention.
7,9,10.
What does the nucleus aMbiguous do?
Motor innervation of pharynx, larynx, upper eso - swallowing, palate elevation.
9, 10, 11.
What does the dorsal motor nucleus do?
Sends autonomic (parasympathetic) fibers to heart, lungs, upper GI. Just vagal nerve.
What are the afferent and efferent branches of the corneal reflex?
Afferent: V1 opthalmic (nasociliary branch)
Efferent: VII (temporal branch, orbicularis oculi).
What are the afferent and efferent branches of the lacrimation reflex?
Afferent: V1 (emotional tears preserved even w/ loss of reflex)
Efferent: VII.
What are the afferent and efferent branches of the jaw jerk reflex?
Afferent: V3 - sensory muscle spindle from masseter
Efferent: V3 - motor, masseter
What are the afferent and efferent branches of the pupillary reflex?
Afferent: II
Efferent: III
What are the afferent and efferent branches of the gag reflex?
Afferent: IX
Efferent: X
What lesion causes jaw deviation TOWARDS side of lesion?
CN V motor lesion - unopposed force from opposite pterygoid muscle
What lesion causes uvula deviation AWAY from side of lesion?
CN X lesion. Weak side collapses and uvula points away.
What lesion causes weakness turning head to contralateral side of lesion (SCM) + shoulder droop on side of lesion (trapezius)?
CN XI lesion.
What lesion causes tongue deviation towards side of lesion?
CN XII. Due to weakened tongue muscles on affected side.
