The lingual nerve is located near the sides of the tongue (specifically below the lateral pterygoid muscle), and is responsible for its senses of taste and touch.
The lingual nerve provides senses to the tongue's front two-thirds, as well as to the underside that surrounds it. It branches off the mandibular nerve and twists around the submandibular duct to reach the tongue. The facial nerve's chorda tympani is one of the nerve fibers the lingual nerve carries to the skull, a process by which the lingual nerve allows taste to be transmitted to the brain. This information is then returned to the front two-thirds of the tongue.
A lingual tonsillectomy — an operation to remove extra tonsillar tissue, or the lingual tonsils, from the back of the tongue — is designed to enlarge the airway to assist with breathing; however, such an operation may damage the lingual nerve, causing the tongue to tingle or feel numb. Certain dental procedures, especially those requiring the use of local anaesthetics, can also damage the lingual nerve.