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mds21910.mpg13071KSegment 1. Patient A, rest condition. Video shows distal myoclonus, with small-amplitude jerks in varying frequency, and tremulousness; left more than right arm. Though present in this patient, the fragment shows no signs of dystonia in the arms. Segment 2. Patient B, coherence entrainment test. Video shows distal myoclonus with small-amplitude jerks and tremulousness during posture of both arms, predominantly in the most affected right arm. Entrainment occurs during tapping with the less affected left arm.

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