dysarthria

Dysarthria is a motor speech disorder caused by impaired movement of the muscles used for speech, including the lips, tongue, vocal cords, and the respiratory system. It results from neurological injury or disease that affects the neuromuscular execution of speech.

There are several primary types of dysarthria: spastic, flaccid, ataxic, hypokinetic, hyperkinetic, and mixed. Each type reflects different patterns of muscle weakness, tone, or discoordination and is associated with characteristic speech features.

Causes include stroke, traumatic brain injury, brain tumors, degenerative diseases (such as amyotrophic lateral sclerosis, Parkinson's disease, multiple sclerosis, Huntington's disease), cerebral palsy, and infections or metabolic disorders.

Symptoms commonly include slurred or slow speech, imprecise consonants, distorted vowels, abnormal pitch or loudness, reduced speaking rate or endurance, and problems with breath control or resonance. Diagnosis is usually by a speech-language pathologist through perceptual evaluation and, when helpful, instrumental assessments of articulation, voice, and respiration.

Management is typically multidisciplinary. Speech therapy aims to improve intelligibility and efficiency through drills, pacing strategies, rate control, breath support, articulatory precision, and compensatory techniques. For severe cases, augmentative and alternative communication (AAC) devices can support communication; underlying conditions may be treated with medication or surgery, as appropriate.

Prognosis varies with etiology and extent of neuromuscular involvement. Dysarthria can be chronic in progressive diseases but may improve with therapy after stroke or injury. It is distinct from apraxia of speech, a planning disorder, and from aphasia, a language disorder.