Dysarthria (say "dis-AR-three-uh) is a disorder that makes it hard to speak well. People who have it understand language. They know what they want to say. For most, reading and writing isn't a problem. But when they talk, their speech is often slurred and hard to understand. Speech therapy can help improve speech.

Dysarthria can be caused by an injury to the brain or a disease of the nervous system. Examples include a stroke, Parkinson's disease, myasthenia gravis, or a head injury. These conditions can affect the nerves that control the lips, jaw, tongue, and soft palate.