Dysarthria

A speech disorder caused by disease or damage to the physical apparatus of speech or to nerves controlling this apparatus. Affected people can formulate, select, and write out words and sentences grammatically; the problem is with vocal expression only. Dysarthria is common in many degenerative neurological conditions, such as multiple sclerosis and Parkinson’s disease. Dysarthria may result from a stroke, brain tumour, or an isolated defect or damage to a particular nerve. Structural defects of the mouth, as occur in cleft lip and palate, can also cause dysarthria. Drug or surgical treatment of the underlying disease or structural defect may improve the ability to speak clearly. Speech therapy is useful.