Dysarthria is seen as a group of motor speech disorders as a result of inadequate muscle tone in the speech mechanism.

It occurs when the articulation (the pronunciation of words) is not precise. This may be caused by brain damage such as strokes, neuromuscular disorders (cerebral palsy), Multiple Sclerosis, Parkinson’s and/or head injury. The brain damage affects the control of the movement of muscles involved in speech, causing them to become weak and paralyzed. This often affects the quality of the speech, making the invidual’s speech less intelligible.

Main types of Dysarthria

  • Spastic Dysarthria: is characterized by spastic paralysis (tightened muscles), weakness and limited range of oral motor movements. This may include reduced force of movements and slow movements.
  • Flaccid Dysarthria: is characterized by flaccid paralysis (loose/limp muscles), weakness, muscle atrophy (decrease in the muscle mass) and/or fasciculations (small tremor in muscles).
  • Ataxic Dysarthria: is characterized by slow movements, inaccurate range of movements, and inaccurate timing of movements.

Symptoms of Dysarthria

  1. Poor articulation or ability to produce precisely pronounced sounds.
  2. Inappropriate timing, by means of prolongations of certain sounds, slow speech or fast speech.
  3. Reduced respiratory capacity, by means of shortness of breath when speaking.
  4. Slurred speech
  5. Irregular stress patterns
  6. Nasal speech
  7. Inappropriate pitch

The speech therapist’s role in Dysarthria

The speech therapist’s role, is to help improve respiration for adequate loudness and breathing during speech. The patient will be taught oral-motor exercises to improve the strength, range, and accuracy of the lip, tongue and cheek muscles. They will also conduct articulation exercises to improve accuracy and precision of sound production, which includes slower rate of speech and modifying prosody (e.g. pitch, stress) for more intelligible speech.