<qa>  What is an attractive hypothesis to explain transient dysfunction?The purpose of this study is to determine the areas of the brain responsible for paroxysmal hyperkinetic movement disorders. Paroxysmal hyperkinetic movement disorders have been clinically recognized for a long time, although the exact neurophysiological mechanism leading to paroxysms of hyperkinetic movement attacks is not well understood. Paroxysmal hyperkinetic movement disorders are heterogenous, and the exact mechanism may differ in each subcategory. In paroxysmal dyskinesias, the idiopathic forms of paroxysmal hyperkinetic movement disorders, it is speculated that transient functional abnormality at the cellular level occurs in the basal ganglia without organic irreversible damage. Ion channel dysfunction is an attractive hypothesis to explain such transient dysfunction. Some patients with paroxysmal hyperkinetic movement disorders have a psychogenic etiology. 