One form of paroxysmal dyskinesia. Note the lack of autonomic signs (lack of hypersalivation) and appropriate conscious awareness during the episode. One or multiple limbs may be affected at once, or in sequence, and voluntary movements and ambulation are typically (but not always) inhibited by the involuntary movements in the limbs. In this episode, movements are best characterized by hypertonicity and flexion.
Courtesy of Dr. Rebecca Packer.