Spasmodic dysphonia (SD) is a voice disorder. The muscles of the throat freeze or go into spasms. Words are strangled and strained or they don’t get out at all. Sounds are also distorted.

The main types of SD include:

  • Adductor spasmodic dysphonia—spasms cause muscles to stiffen and close
  • Abductor spasmodic dysphonia—spasms cause muscles to spastically open
  • Mixed spasmodic dysphonia

Throat
Throat
Spasmodic dysphonia affects the throat muscles.
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Often, the exact cause of SD is unknown. It is a disorder of the central nervous system. The areas of the brain that control these muscle movements are deep within the brain.