Cranial Nerves Flashcards
Trigeminal nerve skeletal components
Malleus, Incus
Trigeminal nerve muscles
Muscles of Mastication, Tensor tympani, Tensor palati, Mylohyoid, ant belly of Digastric
Facial nerve skeletal components
Stapes, Styloid process, Hyoid bone - lesser horn, upper half of body
Facial nerve muscles
Muscles of Facial Expression, Stapedius, Stylohyoid, Post. belly of Digastric
Glossopharyngeal nerve skeletal components
Hyoid bone - greater horn, lower half of body
Glossopharyngeal nerve muscles
Stylopharyngeus
Vagus nerve skeletal components
Cartilages of Larynx
Vagus nerve muscles
All muscles of Larynx, All muscles of Pharynx (except Stylopharyngeus), All muscles of Soft Palate (except Tensor palati)
Spinal Accessory nerve innervates
Sternocleidomastoid, Trapezius
Olfactory nerve is formed by
the axons of the bipolar neurons in the olfactory mucosa
Olfactory nerve axons pass through
the cribriform plate of the ethmoid bone
Olfactory nerve axons synapse on
the olfactory bulb, an extension of the CNS
optic nerve is formed by
the axons of ganglion cells in the retina
The optic nerve is ensheathed by
the oligodendrocytes (CNS)
the optic nerve enters the skull through
the optic canal
if the optic nerve is severed,
you are blind in 1 eye
if optic chiasm severed,
lose some vision in both eyes (peripheral vision)
if sever right optic tract,
lose left field of vision in both eyes
Oculomotor nerve innervates
all of the extraorbital muscles, except:
Superior Oblique
Lateral Rectus
the oculomotor nerve enters the orbit via
the superior orbital fissure
Oculomotor nerve passes through _______, accompanied by
the cavernous sinus accompanied by the trochlear (IV) and abducens nerves (VI)
parasympathetic components of oculomotor nerve
constrictor muscle of pupil, ciliary muscle (alteration of thickness of lens), accomodation
What nerve is the only cranial nerve that is crossed (crosses before it leave the brainstem)?
trochlear nerve
the trochlear nerve innervates
the superior oblique muscle
the trochlear nerve exits via
the superior orbital fissure
what is the largest cranial nerve?
trigeminal nerve
branches of trigeminal nerve
ophthalmic, maxillary and mandibular
trigeminal nerve gives sensory innervation to
the face, scalp, dura mater, eyeball, paranasal sinuses, anterior 2/3 of the tongue, floor of the mouth, teeth, lingual gingiva, palate, nasal cavity, nasopharynx, and external ear
Ophthalmic branch exits through
the superior orbital fissure
Maxillary branch exits through
the foramen rotundum
mandibular branch exits through
the foramen ovale
the abducens nerve innervates
the lateral rectus muscle (abduction of pupil)
the supratrochlear nerve comes out above
the trochlear nerve
action of the superior oblique
pulls down the eye
tensor tympani action
lessens vibration (with loud noise)
tensor palatini
tenses soft palate
action of medial rectus
adducts pupil
action of superior rectus
elevates pupil
action of inferior rectus
depresses pupil
action of inferior oblique
pulls eye up
the facial nerve emerges (exits) at the
cerebellopontine angle
the facial nerve enters the ________ with the ______.
internal acoustic meatus with the CN VIII
the facial nerve descends through
the inner ear
The facial nerve emerges through
the stylomastoid foramen
The facial nerve is ________ sensory, trigeminal is _____ sensory
taste; touch
The parasympathetic component of the facial nerve supplies
the lacrimal and parotid glands
bell’s palsy
damage to the facial nerve; can’t move one side of the face
Vestibulocochlear nerve exits via
the internal acoustic meatus and then divides into cochlear and vestibular divisions
Vestibulocochlear nerve has 2 components:
cochlea and vestibular apparatus (semicircular canals)
Glossopharyngeal nerve exits via
the jugular foramen accompanied with CN X & CNXI
the superior ganglia of the glossopharyngeal nerve gives sensation to
the oropharynx
the inferior ganglia of the glossopharyngeal nerve gives sensation to
(taste) to the posterior third of the tongue
What is the longest cranial nerve
vegas
Emerges just inferior to IX
the vegas nerve
where does the vegas nerve exit?
Exits through the jugular foramen with IX and XI
the vegas nerve nerve gives sensation to
dura of posterior cranial fossa
Concha & external acoustic meatus and external surface of tympanic membrane
Larynx
vegas nerve innervates what muscles?
Muscles of the soft palate, larynx
parasympathetic preganglionic fibers thoracic and abdominal viscera to the junction of the right 2/3 and left 1/3 of the transverse colon (goes to splenic fissure)
Accessory nerve is composed of two parts:
cranial and spinal
cranial part of accessory nerve
leaves the accessory nerve after entering the jugular foramen and joins the vagus nerve
spinal part of accessory nerve
enters through foramen magnum and joins the cranial part at jugular foramen
The hypoglossal nerve emerges from the
hypoglossal canal
The hypoglossal nerve innervates
all lingual muscles with the exception of palatoglossus
If there is a lesion on the left side of the tongue,
the tongue will go to the left
