The sublingual nucleus is located in the brainstem, specifically in the medulla oblongata at the very end of the brainstem, at the base of the fourth ventricle of the medulla oblongata, deep in the sublingual nerve triangle. The fibers emanating from the nucleus accumbens travel between the olivary and vertebral bodies, exit the brain, exit the skull via the sublingual nerve canal, and are distributed to the ipsilateral lingual muscles. The main role of the hypoglossal nerve is to pull the chin-lingual muscle forward, which enables the tongue to extend outward and retract inward mainly by the hyoid lingual muscle. The hypoglossal nerve is innervated only by the contralateral cortical brainstem bundle, which results in ipsilateral hypoglossal neuropathy, resulting in difficulty in ipsilateral tongue extension and a bias toward the affected side when extending the tongue. In the case of supranuclear lesions of the hypoglossal nerve, tongue extension will be biased to the contralateral side of the lesion.