Which cranial nerve transmits fibers from the cochlea to the brain?

The correct choice, the vestibulocochlear nerve (Cranial Nerve VIII), plays a critical role in hearing and balance. This nerve is responsible for transmitting sensory information from the cochlea in the inner ear to the auditory cortex of the brain, facilitating the perception of sound. It comprises two components: the cochlear nerve, which is related to hearing, and the vestibular nerve, which is related to balance.

When sound waves enter the cochlea, they stimulate hair cells, converting mechanical energy into neural impulses. These impulses are carried by the cochlear portion of the vestibulocochlear nerve to the brain for processing. This pathway is essential for auditory function, allowing individuals to perceive and interpret sounds.

The other cranial nerves listed serve different functions. The facial nerve, primarily involved in facial expression and taste sensation from the anterior two-thirds of the tongue, does not transmit auditory information. The trigeminal nerve is primarily responsible for sensation in the face and motor functions such as biting and chewing, and it does not play a role in hearing. Finally, the optic nerve is dedicated to vision, transmitting visual information from the retina to the brain, and is not involved with auditory pathways.