Match the Cranial Nerve With Its Main Function
Each question names a function and asks which cranial nerve carries it. Distractors are drawn from the other eleven nerves, so a right answer means separating nerves that share a territory rather than recognizing an isolated fact.
The matching runs in both directions across a round: sometimes the function is given and you pick the nerve, sometimes the nerve is given and you pick what it does. Start below — the quiz opens on the first question.
The twelve nerves and their main functions
I olfactory carries smell and II optic carries vision, both purely sensory. III oculomotor drives most eye movement plus pupil constriction, lens accommodation and eyelid elevation; IV trochlear supplies the superior oblique, which depresses and intorts the eye; VI abducens supplies the lateral rectus, which abducts it.
V trigeminal is the face: sensation across three divisions, plus the muscles of mastication. VII facial moves the muscles of expression and carries taste from the anterior two-thirds of the tongue. VIII vestibulocochlear carries hearing and balance.
IX glossopharyngeal carries taste from the posterior third of the tongue and pharyngeal sensation. X vagus supplies parasympathetic innervation to the thorax and abdomen along with palate, pharynx and larynx. XI accessory drives sternocleidomastoid and trapezius, and XII hypoglossal moves the tongue.
Which pairs are most often confused
The eye-movement nerves are the classic trap. III, IV and VI all move the eye, and the fastest way to separate them is by the muscle rather than the movement: IV is superior oblique, VI is lateral rectus, III is everything else.
Taste is split across three nerves, which is the second common confusion. VII covers the anterior two-thirds of the tongue, IX the posterior third, and X the epiglottis and pharynx. The sensory-motor classification is worth learning alongside function, because it constrains the answer before you recall the detail.
Verified study data
Nerve functions follow Sonne J, Omole AE and Lopez-Ojeda W, Neuroanatomy, Cranial Nerve, StatPearls, updated January 24, 2025: https://www.ncbi.nlm.nih.gov/books/NBK470353/.
Common questions
How do you match cranial nerves to their functions?
Classify the nerve as sensory, motor or both first — that alone rules out most options. Then attach the function to a specific structure rather than a general action: IV is the superior oblique, VI is the lateral rectus, XII is the tongue.
Which cranial nerve controls eye movement?
Three of them. III oculomotor moves the eye up, down and medially and raises the eyelid, IV trochlear supplies the superior oblique, and VI abducens supplies the lateral rectus.
Which cranial nerves carry taste?
VII facial carries taste from the anterior two-thirds of the tongue, IX glossopharyngeal from the posterior third, and X vagus from the epiglottis and pharynx.
Which cranial nerve is the longest?
X, the vagus nerve. It leaves the medulla and travels through the neck and thorax into the abdomen, supplying parasympathetic innervation along the way.