Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Focal dystonia ?
    ### Response:
    Focal dystonia is a movement disorder that is localized to a specific part of the body. The dystonias are a group of movement problems characterized by involuntary, sustained muscle contractions, tremors, and other uncontrolled movements. Focal task-specific dystonia, or FTSD, interferes with the performance of particular tasks, such as writing, playing a musical instrument, or participating in a sport.
    