Cranial Nerves Flashcards
Name of Cranial Nerve 1
Olfactory
Where does cranial nerve 1 originate?
Olfactory epithelium of caudal nasal mucosa
Through which structure do the axons of cranial nerve 1 pass?
Cribiform plate
Main function of cranial nerve 1
Sense of smell
Name of Cranial Nerve 2
Optic
Functions of cranial nerve 2
vision, pupil size, visual reflexes/responses
Where do the neurons forming cranial nerve 2 originate?
Retina
Through which structure in the eye do the axons of cranial nerve 2 exit?
Optic disc
To which part of the brain is visual information relayed?
Occipital cortex
Does CNN II control the sensory or motor aspect of the pupillary light reflex?
Sensory
Motor–> CNN III
Is CNN II sensory or motor in the menace response?
Sensory
Motor–> CNN VII
Which 3 cranial nerves are involved with eye movement?
III, IV, VI
Which muscle(s) is CNN III responsible for moving around the eye?
DMV rectus, ventral oblique, and levator palpebrae superioris
Which muscle(s) is CNN IV responsible for moving around the eye?
Dorsal oblique
Which muscle(s) is CNN VI responsible for moving around the eye?
Lateral rectus, retractor bulbi
Strabismus
altered eye position; seen with nerve dysfunction
Name of CNN III
Oculomotor
Origin of CNN III
Brainstem
Functions of CNN III
motor innervation to extraocular muscles and constrictor muscle of the pupil
Which of the cranial nerves are parasympathetic?
III, VII, IX, X
Name of CNN IV
Trochlear
Main function of CNN IV
mov’t of eye muscles (Dorsal oblique)
Name of CNN V
Trigeminal
Main functions of CNN V (sensory and motor)
Sensory: face, eye, mouth
Motor: muscles of mastication
What are the three main branches of CNN V. Which are sensory and/or motor?
1) Opthalmic (sensory)
2) Maxillary (sensory)
3) Mandibular (sensory and motor)
Name of CNN VII
Facial
Functions of CNN VII
1) motor to muscles of facial expression (menace response)
2) sensory to inner pinna of ear
3) Taste rostral 2/3 tongue
4) Parasympathetic to lacrimal and salivary glands
Name of CNN VIII
Vestibulocochlear
Functions of CNN VIII
Balance and hearing
Name of CNN IX
Glossopharyngeal
Functions of CNN IX
1) sensory and motor to pharynx (gag response)
2) sensory to caudle 1/3 tongue
3) Carotid sinus (baroreceptors) and carotid body (chemorecptors)
4) parasympathetic to salivary glands
Name of CNN X
Vagus
Functions of CNN X
1) sensory and motor to pharynx (gag reflex)
2) sensory to viscera
3) Parasympathetic to viscera
4) carries recurrent laryngeal
5) carries cranial laryngeal
What nerve does the recurrent larygeal become?
Caudal laryngeal
Which muscle of the larynx does the caudal largyneal NOT supply?
cricothyroid
Cricothyroid is supplied by what nerve?
Cranial laryngeal
What muscle functions to open the glottis? What never supplies it?
Cricoarytenoideus; caudal laryngeal nerve
Name of CNN XI
Accessory
Functions of CNN XI
Motor to trapezius and other neck muscles
Name of CNN XII
Hypoglossal
Functions of CNN XII
Motor to tongue muscles (both intrinsic and extrinsic)
Which CNN exit through the orbital fissure?
III, IV, VI
Which CNN exit through the tympano-occipital fissure?
IX, X, XI
Menace response (sensory and motor)
S: II
M: VII
Pupillary light reflex (PLR)
S: II
M: III
Gag Reflex
S: IX
M: IX, X
Corneal Reflex
S: V
M: VII, VI
