Study author Dr. Karin Rosenkranz, of the University College London Institute of Neurology, said that musician's dystonia occurs in those who have practiced particularly complicated movements for years. The muscle spasms are usually painless and generally occur only when playing the instrument.

Researchers applied low-amplitude vibration to the hand muscles in 24 people: six who had musician's dystonia, six professional musicians with no dystonia, six healthy non-musicians, and six people with writer's cramp -- another type of dystonia.

In a 15-minute intervention, muscle vibration was applied to a thumb muscle and the participant's attention was either directed on that muscle itself or away from the muscle.

The study, published in the journal Neurology, found that the vibration intervention in which subjects had to attend to their thumb muscle tended to restore a more normal pattern in people with musician's dystonia and in a less pronounced way in the those with writer's cramp.