Which cranial nerve is associated with taste sensation?

The facial nerve (VII) and glossopharyngeal nerve (IX) are both crucial for taste sensation. The facial nerve primarily innervates the anterior two-thirds of the tongue, allowing for the perception of taste in that area. It transmits taste sensations through the chorda tympani branch of the nerve. On the other hand, the glossopharyngeal nerve provides taste sensation from the posterior one-third of the tongue. This dual contribution ensures that taste stimuli from the majority of the tongue are transmitted to the brain for processing.

Other nerves mentioned in the choices do not play a significant role in taste sensation. The optic nerve is involved in vision, the olfactory nerve is responsible for smell, and the vagus nerve has various functions, such as regulating heart rate and digestive tract activity, but it does not primarily convey taste. Therefore, the facial and glossopharyngeal nerves are uniquely and directly associated with the sense of taste.