Which cranial nerve is responsible for hearing and balance?

• A. Trigeminal nerve
• B. Olfactory nerve
• C. Glossopharyngeal nerve
• D. Vestibulocochlear nerve

Answer: (D)

Hearing and balance are transmitted to the brain by a single cranial nerve—the vestibulocochlear nerve. This nerve, cranial nerve VIII, has two functional parts: the cochlear division for hearing and the vestibular division for balance and spatial orientation. Because these two sensory modalities rely on this same nerve to reach the brain, it is the one responsible for both hearing and balance. If this nerve is damaged, you can see sensorineural hearing loss, vertigo, and balance problems. The other nerves listed control different functions—trigeminal for facial sensation and chewing, olfactory for smell, and glossopharyngeal for taste and swallowing—so they don’t mediate hearing or balance.