This document provides information about the 12 pairs of cranial nerves, including their names, exit points from the skull, branches, functions and potential defects or test findings if damaged. It lists the nerve name, exit point from the skull, branches, motor or sensory functions and visceral or somatic innervation. Colour coding indicates the different functional categories of the nerves.

1. Nerve Exits Skull Branches Branchial Somatic Somatic Special Visceral Parasympathetic Defects/Test
motor motor sensory sensory sensory (not complete)
I Olfactory Cribriform plate Smell No smell
II Optic (from retinal cells) Optic canal 2branchescross @chiasm Sight See separate notes
III Oculomotor Superior orbital Superior and inferior LPS s rectus Ciliary m. and Complete: ptosis and
fissure division (carries (sup division) sphincter pupillae via laterally deviated eye
parasymp) m,i recti ciliary ganglion and with dilated pupil (no
inf. oblique short ciliary nerves Va parasymp.)
IV Trochlear Superior orbital Sup. oblique Can’t look in and
fissure down
Opthalmic division of Superior orbital Frontal, lacrimal, Forehead and nose,
Va trigeminal fissure nasociliary: long, short, meninges
ant ethm, infratrochlear
Maxillary division of Foramen Zygomatic, infraorbital, Cheeks to upper lip, Loss of sensation,
Vb trigeminal rotundum nasopalatine, greater/ external surface of shingles, jaw deviates
lesser palatine, pharyng. tympanic membrane to weak side when
Mandibular division of Foramen ovale Ant to muscles, post: 1st arch muscles of Lower lip and jaw opening mouth
Vc trigeminal lingual, inf alveolar, mastication plus
auriculotemporal MATT
VI Abducent Superior orbital Lat. rectus Eye deviates med
fissure when looking laterally
VII Facial Int. auditory - Greater petrosal 2nd arch Ear and tympanic Taste to ant Lacrimal and hayfever Loss of taste to ant.
(motor root and nervous meatus - chorda tympani muscles of facial membrane 2/3 of tongue glands via 2/3 of tongue, muscles
intermedius) Motor fibres - n. to stapedius expression plus pterigopalatine of facial expression,
exit via - n. to post digastric, POSS ganglion, sublingual Bell’s palsy
stylomastoid occl, stylohyoid and submandibular
foramen - temporal, zygomatic, glands via
buccal, mandibular, submandibular
cervical (from parotid) ganglion
VIII Vestibulocochlear Int. auditory Hearing, Hearing and balance
meatus Balance impaired
IX Glossopharyngeal Jugular foramen Lesser petrosal, to 3rd arch stylo- Sensation to Taste to post Parotid gland via otic Function of carotid
stylopharyngeus, pharyngeus posterior 1/3 of 1/3 of tongue ganglion baroreceptors
sensory, taste and to tongue, int. surface impaired, no gag
carotid sinus and body of tymp. membrane reflex
X Vagus Jugular foramen Pharyngeal, internal and 4th arch sup. External ear Pharynx, Neck, thorax, Deviation of uvula
external superior laryngeal = crico- larynx, abdomen towards normal side
laryngeal, recurrent thyroid, pharynx- viscera
laryngeal, cardiac, geal plexus = m.
left/right = ant/post of the palate and
vagus pharynx, 6th arch
rec. laryngeal
XI Accessory Jugular foramen Spinal and cranial root Spinal root: Can’t turn head or
sternocleido- shrug shoulders
mastoid,
trapezius,
cranial root to X
XII Hypoglossal Hypoglossal To tongue and ansa Muscles of Tongue deviates
canal cervicalis (geniohyoid tongue exc. towards lesion
and thyrohyoid) palato-glossus
(pharyngeal
plexus)
Yellow: special sensory, orange: branchial motor, blue: somatic motor