Is dystonia a sensory disorder?
On first appearance, dystonia is a movement disorder. It is characterized by abnormal postures and movements. Sensation seems normal. There are clues, however, that sensory function may not be completely normal and that sensory features are important. Since the sensory system is an important influence on the motor system, abnormalities of the sensory system could be relevant in causing motor dysfunction. Sensory tricks can relieve a dystonic spasm. The most commonly noted is the “geste” in spasmodic torticollis where, for example, a finger placed lightly on the face will neutralize the spasm. Such tricks are seen in all forms of dystonia. Pressure on the eyelids might improve blepharospasm, a toothpick in the mouth might relieve tongue dystonia, and sensation applied to parts of the arm might improve a writer’s cramp. On the other hand, sensory stimulation might trigger dystonia. This might be called a reverse “geste.” Examples include a tart taste producing tongue dystonia or a loud n
