- People with dystonia have serious muscle contractions that cause abnormal movements or postures. This significantly affects their daily lives. The common type is called organic. The other type is psychogenic. People with this type have typical symptoms plus some psychological effects. Researchers will look at how rapid transcranial magnetic stimulation (rTMS) of the brain combined with stimulation of a nerve affects the ability to detect sensations. They will compare the responses of people with different types of dystonia. They will also compare the responses of people with dystonia to responses of people without it. This study may help us learn more about the nature of different types of dystonia.