Movement disorders are sometimes referred to by medical professionals as extrapyramidal diseases because this class of disorders is distinct from the disorders caused by disorders of the pyramidal region of the brain . Researchers have determined that movement disorders are caused by diseases in various parts of the brain, including the substantia nigra, the subthalamic nucleus, the globus pallidus, the striatum, and the basal ganglia.
Movement disorders are usually broken down into two types of movement: hyperkinetic movement and hypokinetic movement. Hyperkinetic movement disorders are characterized by a significant and excessive amount of motor activity. This type also includes cases in which there is a significant amount of abnormal involuntary movement. Hypokinetic movement disorders are those in which there is an abnormally reduced amount of intentional motor activity.