"The hypoglossal (CN XII) nerve controls tongue movement. Nuclear or infra-nuclear lesions produce paralysis, atrophy, and fasciculations of the tongue on the involved side. Supranuclear lesions produce mild to moderate contralateral weakness that may be transient. (Bilateral supranuclear lesions, seen in pseudobulbar palsy, produce moderate to severe inability of the tongue to function)".¹ Bilateral UMN … Continue reading Aetiology of CN XII Palsy