| CN I Olfactory Nerve |
olfactory mucosa of nasal cavity | cribriform foramina of ethmoid bone | olfaction | ||
| CN II Optic Nerve |
retina of eye | optic foramen of sphenoid bone | vision | optic nerves unite at optic chiasm - see Figs. 15.8, 17.11, 19.18; optic tracts travel to thalamus | |
| CN III Oculomotor Nerve |
brainstem | superior orbital fissure of sphenoid bone | somatic: supplies 4 extrinsic eye muscles & levator palpebra superioris; autonomic: supplies sphincter pupilla (pupillary constrictor) & ciliary muscle | extrinsic (extraocular) eye muscles control movements of eyeball | |
| CN IV Trochlear Nerve |
brainstem | superior orbital fissure of sphenoid bone | supplies one extrinsic eye muscle | ||
| CN V Trigeminal Nerve |
brainstem | foramina in sphenoid bone | innervates muscles of mastication | three divisions of CN V: ophthalmic, maxillary, mandibular | |
| CN VI Abducens Nerve |
brainstem | superior orbital fissure of sphenoid bone | supplies one extrinsic eye muscle | ||
| CN VII Facial Nerve |
brainstem | internal acoustic meatus & other foramina | innervates muscles of facial expression; also lacrimal, submandibular & sublingual glands | ||
| CN VIII Vestibulocochlear Nerve |
inner ear | internal acoustic meatus | inner ear is partitioned into cochlea and vestibular complex (vestibular complex detects position/acceleration/rotation of head) | ||
| CN IX Glossopharyngeal Nerve |
sensory fibers - tongue and carotid bodies; motor fibers - brainstem | jugular foramen | general sensation and taste from posterior 1/3 of tongue and carotid bodies (receptors that monitor blood oxygen and carbon dioxide) | innervates parotid (salivary) gland and one pharynx muscle | glosso = tongue |
| CN X Vagus Nerve |
brainstem | jugular foramen; (travels into neck, thorax, & abdomen) | sensory information from pharynx, larynx, heart, lungs, and most abdominal organs | somatic: innervates pharynx and larynx muscles; visceral: innervates heart, lungs, most abdominal organs, etc. | "vagal" refers to vagus nerve |
| CN XI Accessory Nerve |
brainstem (& spinal cord) | jugular foramen | innervates trapezius, sternocleidomastoid, etc. | has cranial roots and spinal roots | |
| CN XII Hypoglossal Nerve |
brainstem | hypoglossal canal of occipital bone | innervates intrinsic and extrinsic tongue muscles |