Soon it would be discovered that the theory about the corpus striatum would not be completely incorrect.By the late 19th century, a few hyperkinesias such as Huntingtons chorea, post-hemiplegic choreoathetosis, Tourettes syndrome, and some forms of both tremor and dystonia were described in a clinical orientation. However, the common pathology was still a mystery. British neurologist William Richard Gowers called these disorders "general and functional diseases of the nervous system" in his 1888 publication entitled A Manual of Diseases of the Nervous System. It was not until the late 1980s and 1990s that sufficient animal models and human clinical trials were utilized to discover the specific involvement of the basal ganglia in the hyperkinesia pathology. In 1998, Wichmann and Delong made the conclusion that hyperkinesia is associated with decreased output from the basal ganglia, and in contrast, hypokinesia is associated with increased output from the basal ganglia. This generalization, however, still leaves a need for more complex models to distinguish the more nuanced pathologies of the numerous diverse hyperkinesias which are still being studied today.In the 2nd century, Galen was the first to define tremor as "involuntary alternating up-and-down motion of the limbs." Further classification of hyperkinetic movements came in the 17th and 18th centuries by Franciscus Sylvius and Gerard van Swieten. Parkinsons disease was one of the first disorders to be named as a result of the recent classification of its featured hyperkinetic tremor. The subsequent naming of other disorders involving abnormal motions soon followed.
In evaluating the individual with a suspected form of hyperkinesia, the physician will record a thorough medical history, including a clear description of the movements in question, medications prescribed in the past and present, family history of similar diseases, medical history, including past infections, and any past exposure to toxic chemicals. Hyperkinesia is a defining feature of many childhood movement disorders, yet distinctly differs from both hypertonia and negative signs, which are also typically involved in such disorders. Several prominent forms of hyperkinetic movements include:

Ataxia
The term ataxia refers to a group of progressive neurological diseases that alter coordination and balance. Ataxias are often characterized by poor coordination of hand and eye movements, speech problems, and a wide-set, unsteady gait. Possible causes of ataxias may include stroke, tumor, infection, trauma, or degenerative changes in the cerebellum. These types of hyperkinetic movements can be further classified into two groups. The first group, hereditary ataxias, affect the cerebellum and spinal cord and are passed from one generation to the next through a defective gene. A common hereditary ataxia is Friedreichs ataxia. in contrast, sporadic ataxias occur spontaneously in individuals with no known family history of such movement disorders. Athetosis
Athetosis is defined as a slow, continuous, involuntary writhing movement that prevents the individual from maintaining a stable posture. These are smooth, nonrhythmic movements that appear random and are not composed of any recognizable sub-movements. They mainly involve the distal extremities, but can also involve the face, neck, and trunk.