Cranial Nerves Flashcards
List the cranial nerves
- Olfactory
- Optic
- Oculomotor
- Trochlear
- Trigeminal
- Abducent
- Facial
- Vestibulocochlear
- Glossopharyngeal
- Vagus
- Spinal Accessory
- Hypoglossal
Cranial nerve I
Olfactory
Cranial nerve II
Optic
Cranial nerve III
Oculomotor
Cranial nerve IV
Trochlear
- Cranial nerve V
- Va
- Vb
- Vc
- Trigeminal
- Opthalmic
- Maxilliary
- Mandibular
Cranial nerve VI
Abducent
Cranial nerve VII
Facial
Cranial nerve VIII
Vestibulocochlear
Cranial nerve IX
Glossopharyngeal
Cranial nerve X
Motor to (4)
- Autonomics
Notable branches of larynx (2)
- Insertion
- Cranial Route
Vagus
- Laryngeal muscles
- Salpingopharyngeus muscle
- Palatopharyngeus Muscle
- Pharyngeal constrictors
Thorax and upper abdomen
- Superior and Recurrent Laryngeal nerve
- Pharyngeal nerve
- Rostral to CN9
- Jugular foramina to the junction of internal and external carotids.
Cranial nerve XI
Spinal Acessory
Cranial nerve XII
Hypoglossal
Olfactory
Cranial nerve I
Optic
Cranial nerve II
Oculomotor
Cranial nerve III
Trochlear
Cranial nerve IV
- Trigeminal
- Opthalmic
- Maxilliary
- Mandibular
- Cranial nerve V
- Va
- Vb
- Vc
Abducent
Cranial nerve VI
Facial
Cranial nerve VII
Vestibulocochlear
Cranial nerve VIII
Glossopharyngeal
Cranial nerve IX
Vagus
Cranial nerve X
Spinal Acessory
Cranial nerve XI
Hypoglossal
Cranial nerve XII
CN1
roles (1)
Route (2)
Special sensory for olfaction.
Olfactory axons on the nasal epithelium penetrate the cribiform plate and send afferents to the olfactory bulb.
The olfactory Bulb extends straight into the telencephalon at the entorhinal cortex.
CN2
- roles
- Route
- insertion
Visual sense
Through optic fissure and meets at optic chiasm
Into Diencephalon
CN3
roles (3)
Route (1)
Insertion (1)
Innervates intraocular and extrocular muscles
- Special motor to the muscles of the eye
- Special motor to the uscles of the upper eyelid (with sympathetics)
- Ciliary Ganglion: Iris constrictor and lens accomodation
- Via Orbital fissure
- Into rostroventral and fairly medial midbrain.
CN4
- roles
- Route
- Insertion
- Special Motor to superior oblique muscle of orbit
- Through orbital fissure
- Into DORSAL rostral pons.
CN5
- General roles (7) and Pharyngeal association
- Insertion
- Main Branches (3)
- Route(s)
- General sensory to the face and jaw (first pharyngeal arch)
Motor to the muscles of mastication
- temporalis
- masseter
- medial and lateral pterygoids
Motor to
- Tensor veli palatini (of palate)
- Mylohyoid
- Anterior belly of digastric
- Tensor Tympani
Inserts the pons to trigeminal ganglion
- Ophthalmic goes through orbital fissure
- Maxilliary goes through the foramen rotundum
- Mandibular goes through the foramen ovale
CN6
roles
Route
Insertion
- Special Motor to lateral rectus
- Via orbital fissure
- Enters the brain at the junction of the pons and medulla
CN7
roles (3)
Insertion
Pharyngeal arches
- Face motor role
- Special sense from anterior part of tongue
- Parasympathetic secretomotor to sublingual, submandibular and lacrimal glands. Although it passes through the Parotid, it does not innervate it)
- Medial between ventral pons and medulla
Partially first arch but mostly innervates second arch
CN8
roles
Route
insertion
- Special sensory for
a) Vestibular system
b) Auditory system - Via Internal auditory meatus
- Lateral to the facial nerve at ventrral junction between the Pons and medulla
CN9
roles 3
- insertion
- Route
- Pharangeal association
Mixed sensory, motor and autonomic
- Sensory: special and general to poterior 1/3 of tongue and dorsal oropharynx
- Motor to stylopharyngeus
- Parasympathetic to parotid and mucosal glands inc palatine tonsil (via otic ganglion)
- Caudal to CN8
- Via the jugular foramen
- Arch 3
CN10 roles
Somatic Motor
Motor
Palatoglossus (the only muscle of the tounge NOT associated with hypoglossal)
Salpingopharyngeus Muscle
Speech Muscles of the larynx and three laryngeal Constrictors
CN11
roles
route 2
Insertion
Cervical accessory is motor to Sternocleidomastoid and trapezius
Cranial Accessory is accessory motor to vagus area.
- Enters through the foramen magnum
- Accessory division exits throught the jugular foramen and into the neck
Lateral medulla caudal to Vagus insertion
CN12
role
insertion
Route
Motor to the almost all of the tongue muscles (instrinsic and extrinsic) the exception is the palatoglossus.
Emerges from the ventrolateral medulla
Through the Hypoglossal Canal
Cranial Nerves with parasympathetic function
- Oculomotor : Pupilliary reflex and lens thickening.
- Facial :
a) Submandibular and sublingual glands via chorda tympani
b) Nasal sinuses and larimal gland via pterygopalatine ganglion. - Glossopharyngeal : parotid gland via otic ganglion
- Vagus : various abdominal
Orbital Features
- Superior rectus
- Inferior Oblique
- Superior Oblique
- Lateral rectus
- Inferior rectus
- Ciliary ganglion
- Medial Rectus
Muscles innervated by oculomotor
Special Motor
- Superior rectus
- Medial Rectus
- Inferior rectus
- Inferior Oblique
Autonomic (via ciiiary ganglion)
- Ciliary Muscle
- Iris
CN7
Routes and branches
7
- Petrosal nerve gives sympathetics to cranial sinuses
- nasal, palatine, pharyngeal and lacrimal glands.
- Autonomic motor to stapedius
- Chorda Tympani (merely passes close to the ear)
- Chorda Tympani to submandibular and sublingual gland
- Chorda Tympani special sensory to the anterior 2/3 of the tongue .
- All motor and sensory enter petrous temporal bone via internal auditory meatus
- To facial canal, exiting at the stylomastoid foramen.
- Two branches (to auricularis and posterior belly of digastric)
- Main branch enters parotid gland, where it splits into 5
Salpingopharyngeus Muscle and palatopharyngeus muscle.
Roles Together
Seperate roles (2)
Innervation
Together, they raise the Hyoid, and thus the pharynx and larynx, allowing swallowing.
Salpingopharingeus Inserts just medial to the eustacian tubes, causing them to be opened on swallowing and thus allowing an equalization of pressure.
Palatopharyngeus causes the Larynx to be relatively drawn back. In conjunction with the action of the epiglottis, this protects the windpipe during swallowing.
Both are innervated by the vagus nerve.
