DYSTONIA By N., Pam M.S. - April 7, 2013 An abnormal and involuntary tension or contraction of the muscles resulting in a distorted posture. See extrapyramidal effects. DYSTONIA: "Joe had dystonia eveidenced by his arched back." Related Psychology Terms FIBRILLATION ROLFING MUSCLE TWITCH SPASM GASTROINTESTINAL MOTILITY SOMATIC FUNCTION FLUPHENAZINE STANCE REFLEX ISOMETRIC CONTRACTION TONIC Cite this page: N., Pam M.S., "DYSTONIA," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/dystonia/ (accessed October 16, 2019).