Dystonia: Then and now.

<bold>Introduction: </bold>Dystonia is a rare disorder that has undergone extensive scientific investigation leading to a transformation of understanding over the past century.<bold>Methods: </bold>This manuscript was prepared through a review of relevant literature for each topic.<bold>Results: </bold>Historically dystonia was considered the manifestation of psychiatric disorders. Subsequently, investigations have firmly established this as a neurological disorder. Though electrophysiological and imaging, dystonia is thought to arise from a loss inhibition of motor programs, defective sensorimotor integration and abnormal plasticity. The genetic studies in dystonia have revealed the hereditary nature of many forms of familial dystonia. Treatment of dystonia has focused primarily on botulinum toxin for focal and segmental dystonia and deep brain stimulation of the globus pallidus interna for generalized and medically refractory focal dystonia.<bold>Conclusion: </bold>The progress in dystonia in the past century has revised the concepts of this disorder, increased knowledge of genetics and underlying pathophysiology, and provides new therapeutic targets. To promote future research the development of diagnostic criteria, biomarkers and validated rating scales for each form of dystonia is essential. [ABSTRACT FROM AUTHOR]