Cranial nerves Flashcards
CN I
Olfactory nerve: Special sensory (smell) from NC, fibers exit neurocranium via cribriform plate of ethmoid bone
CN II
Optic nerve: sensory
-Special sensory (sight) from eye,
- optic chiasm, exit neurocranium via optic canals
CN III
Oculomotor nerve: mixed
- Somatic - extraocular muscles – S rectus, M rectus and I rectus, I oblique, levator palpebrae superioris
- Visceral motor (pre-synaptic PS) to constrict pupil, accommodate lens.
- Exits neurocranium -> S orbital fissure
CN IV
Trochlear nerve: Motor
- Somatic - S oblique muscle
- Exits neurocranium -> S orbital fissure
CN V (1)
Trigeminal nerve: Sensory
Ophthalmic division
- General sensory from skin of
forehead, external nose, and philtrum of upper lip
- Exits -> Supraorbital Fissure
CN V (2)
Trigeminal nerve: Sensory
Maxillary division
- General sensory from skin of face
overlying the maxilla, NC, upper teeth, and palate –
- Exits -> Foramen Rotundum
CN V (3)
Trigeminal nerve: Mixed
Mandibular division
- General sensory from skin over the
mandible, lower lip, and TMJ
- Branchial motor to muscles of mastication, tensor veli palatini, A belly of digastric, tensor tympani and mylohyoid
CN VI
Abducent nerve: Motor
- Somatic motor to L rectus muscle.
- Exits -> superior orbital fissure
CN VII (Sensory)
Facial nerve: Mixed
Sensory: Special sensory (taste) from A
2/3rds of tongue – Chorda tympani -
Exits -> Intracranial
All branches enter TB through Internal Acoustic Meatus
Somatic sensory – to a small portion of
skin in the external auditory meatus
CN VII (Motor)
Branchial motor to muscles of facial
expression, P belly of digastric, stylohyoid – Exits -> Stylomastoid Foramen.
- Stapedius – Intracranial
Visceral motor - lacrimal gland, nasal and palatine mucosal glands, submandibular and sublingual salivary glands – Intracranial
CN VIII
Vestibulocochlear Nerve: Sensory
Special sensory (hearing and equilibrium) from inner ear
- Exits -> internal acoustic meatus to reach
vestibular system (balance) and cochlea (hearing) of inner ear
CN IX (Sensory)
Glossopharyngeal nerve: Mixed
- somatic sensory from palatine tonsil, SP, and P 1/3 of tongue
- Special sensory (taste) from P 1/3rd of tongue
- Visceral sensory: carotid body (chemoreceptor) and carotid sinus (baroreceptor)
CN IX (Motor)
Branchial motor to muscle of pharynx
(stylopharyngeus)
- Visceral (PS) motor to parotid gland
Exits -> jugular foramen
CN X (Sensory)
Vagus nerve: Mixed
- somatic sensory: skin P to ear, external auditory canal
- Special sensory (taste): epiglottis, tongue root
- Visceral sensory: I pharynx and larynx mucosa, thoracic and abdominal viscera
CN X (Motor)
Vagus nerve: Mixed
Branchial motor to muscles of the pharynx,
larynx, and palate + palatoglossus (Including: cricothyroid, levator veli palatini,
salpinogpharyngeus, palatopharyngeus,, pharyngeal constrictors).
- Visceral motor: thoracic and abdominal
organs
Exits -> jugular foramen
CN XI
Spinal accessory nerve: Motor
Somatic motor: trapezius and sternocleidomastoid (SCM) muscles
- Arises as series of rootlets from first cervical segments of spinal cord which enter skull -> foramen magnum.
- Exits -> jugular foramen
CN XII
Hypoglossal nerve: Motor
Somatic motor: muscles in tongue, those that attach to it (styloglossus, hyoglossus, genioglossus and intrinsic muscles of tongue).
- Exits -> hypoglossal canal
