Cranial nerve basics

I: Olfactory
Sense of smell
Exits through cribriform plate

II: Optic
Sense of sight
Exits through optic canal

III: Oculomotor
Pupil constriction
All EOM's except lateral and lateral & down
Superior orbital fissure

IV: Trochlear
Lateral & downward eye movement
Superior orbital fissure
Only cranial nerve that decussates (unless you count partial decussation in optic chiasm

V-1: Trigeminal, ophthalmic branch
Sensation to upper face (crown of head extending to below the lower lid and tip of the nose)
Superior orbital fissure

V-2: Trigeminal, maxillary branch
Sensation to mid-face (lower lid to upper teeth, part of the bottom nose)
Foramen rotundum

V-3: Trigeminal, mandibular branch
Sensation to lower face (lower jaw and pre-auricular area)
Motor to the muscles of mastication
Foramen ovale

VI: Abducens
Lateral eye movement
Superior orbital fissure

VII: Facial, motor branch
Muscles of facial expression
Note that on physical exam, can differentiate between peripheral lesions of the facial nerve and lesions of the facial nerve nucleus in the brainstem by noting whether or not the forehead can wrinkle; if only the lower face is weak, suggests upper motor neuron lesion
Stylomastoid foramen, traverses parotid gland

VII: Facial, sensory branch
Taste to anterior 2/3 of tongue (via chorda tympani); stapedius m.; parasympathetic innervation of lacrimal and salivary glands
Acoustic meatus

VIII: Vestibulocochlear
Hearing and balance/vestibular sensation
Internal acoustic meatus (vestibular branch enters semicircular canal)

IX: Glossopharyngeal
Plain sensory, taste, parasympathetic and motor components
Afferent limb of gag reflex
Tympanic nerve (nerve of Jacobson) is a small branch supplying sensation to the middle ear; associated with ear pain in patients with pharyngeal lesions
Jugular foramen

X: Vagus
Visceral parasympathetic innervation, plain sensory, motor to larynx (via recurrent laryngeal nerve) and pharynx
Efferent limb of the gag reflex
Auricular branch (nerve of Arnold) supplies sensation to the inner ear; associated with ear pain in patients with laryngeal lesions
Jugular foramen

XI: Spinal accessory
Motor to sternocleidomastoid and trapezius muscles
Jugular foramen

XII: Hypoglossal
Motor to tongue
Hypoglossal canal

Nerves in the cavernous sinus: III, IV, V-1, V-2