#twitch__twitching__vellication  a sudden spasm; especially one caused by a nervous condition
  supertype:  muscle_spasm__spasm__cramp  a painful and involuntary muscular contraction
  subtype:  tic  a local and habitual twitching especially in the face
  subtype:  blepharism  condition in which a person blinks continuously
  subtype:  fibrillation.twitch  muscular twitching involving individual muscle fibers acting without coordination
     subtype:  atrial_fibrillation  fibrillation of the muscles of the atria of the heart
     subtype:  ventricular_fibrillation__ventricularfibrillation  fibrillation of heart muscles resulting in interference with rhythmic contractions of the ventricles and possibly leading to cardiac arrest
  subtype:  fasciculation  muscular twitching of contiguous groups of muscle fibers

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