Onset movement disorders are rare neurological disorders that manifest as repeated sudden episodes of abnormal movements with normal interictal periods. They are divided into 3 categories: 1) episodic abnormal movements: including the following 4 subcategories: (1) choreoathetosis induced by movement; (2) choreoathetosis with abnormal muscle tone; (3) dystonia induced by continuous movement; (4) nocturnal onset dystonia. 2. episodic ataxia 3. episodic tremor Most primary cases have a family history, while secondary cases can be seen in multiple sclerosis, traumatic brain injury, certain endocrine diseases such as hyperthyroidism and hypoglycemia.