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