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jws-mds.20516.mpg13327K Segment 1. Couplet contractions followed by 1-2 second pause. (Laryngoscope) (Videofluoroscopy) Segment 2. 1 hour after 2 doses of sumatriptan 50 mg. Irregular contractions (loss of couplet pattern). Contractions occur during inspiration and expiration. Contractions appear to be absent during breath holding. This video presentation has been abbreviated. The full version will appear on theMovementDisorders DVD Supplement, which is issued bi-annually.

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