Which cranial nerve carries afferent vestibular information from the inner ear to the brain?

• A. CN VII (facial)
• B. CN IX (glossopharyngeal)
• C. CN V (trigeminal)
• D. CN VIII (vestibulocochlear nerve)

Answer: (D)

The afferent information from the inner ear’s balance organs travels through the vestibular portion of the eighth cranial nerve. This nerve, often paired with hearing fibers in the same trunk, carries signals from the semicircular canals that detect angular head movement and from the otolith organs (utricle and saccule) that detect linear acceleration and gravity. Those signals go to the brainstem vestibular nuclei, supporting balance, posture, and gaze stabilization via reflex pathways like the vestibulo-ocular reflex. The other nerves listed have different primary roles (facial motor and sensation, tongue and throat sensation, facial sensation), so they don’t carry vestibular afferent information.