Cranial Nerves Flashcards
Name the 12 cranial nerves
CNI Olfactory CNII Optic CNIII Oculomotor CNIV Trochlear CNV Trigeminal CNVI Abducent CNVII Facial CNVIII Vestibulocochlear CNIX Glossopharyngeal CNX Vagus CNXI Accessory CNXII Hypoglossal
What are the 3 motor columns medial to lateral?
Somatic, Branchial, Visceral (autonomic)
What are the 3 sensory columns medial to lateral?
Visceral, Somatic, Special
What is the pupillary light reflex?
light is shone into the eye which sends signals from the retina via the optic nerve to the brain- motor fibres from the Edinger Westfal nucleus innervate the sphincter pupillae muscle which constricts the pupils
The pupillary light reflex is used to check which region of the brainstem?
midbrain
Describe the Corneal blink reflex
cotton wool is touched against the retina which is sensed by Opthalmic division of Trigeminal nerve CNV1 and motor response is mediated by Facial nerve CNVII triggering blinking of the eye (orbicularis oculi)
The Corneal blink reflex is used to assess function at what level of the brainstem?
Pons
Describe the gag reflex
Stimulation of the posterior tongue/oropharynx stimulates glossopharyngeal nerve (afferent) and triggers gag = mediated by the vagus nerve
The gag reflex is used to test function in what region of the brainstem?
Medulla
What are the somatic motor functions?
extra-ocular muscles, muscles of tongue
What are the branchial motor nuclei?
Trigeminal nucleus (mastication) Facial nucleus, nucleus ambiguus, Acessory nucleus
What is the edinger westfall nucleus?
Oculomotor nucleus -> for pupillary reflex
What nuclei are in the visceral motor column?
EW-nucleus, Superior and inferior salivatory (CNVII, CNIX) Vagus nucleus
What nuclei are in the visceral sensory column?
CNVII, IX, X = Nucleus Solitarius
What nuclei are in the somatic sensory column?
CNV, VII, IX, X
What is the nuclei in the special sensory column
CNVIII
How is the nucleus solitarius organised?
Rostral = gustatory nucleus (taste buds and palate) Caudal = visceral sensory division
Where does the olfactory nerve exit the skull? where does the neurons synapse?
from the nose it picks up smells and takes this info through the cribiform plate of the ethmoid bone and synapses in the olfactory bulb - info ends up in the insular cortex (gustatory nucleus)
