Which cranial nerve is tested by asking the patient to stick out their tongue?

The hypoglossal nerve, which is cranial nerve XII, is responsible for controlling the movements of the tongue. When a clinician asks a patient to stick out their tongue, they are assessing the function of this nerve. Proper function of the hypoglossal nerve allows for tongue movements necessary for speech and swallowing. If the nerve is functioning correctly, the tongue will protrude symmetrically; any deviation or weakness may indicate a problem with this nerve. Therefore, understanding the role of the hypoglossal nerve is key in this type of neurological assessment.