Tongue Signs

The tongue is heavily innervated and plays a central role in articulation, swallowing, and tasting. Unilateral weakness is usually well tolerated. Intermittent weakness of the tongue is highly suspicious of myasthenia gravis, while progressive weakness and atrophy are typical for amyotrophic lateral sclerosis(ALS). Tongue weakness without atrophy or fasciculations is a sign of upper motor neuron or cerebellar involvement. Lingual dysarthria should be differentiated from other types of dysarthria. Tongue tremor is common and may be confused with fasciculations. Inspection of the tongue is often diagnostically useful in neuromuscular patients. Fasciculations, myokymia, grooving with pressure, and trigrooved tongue are examples.