Effect of Vocal Exercise After Botulinum Toxin Injection for Spasmodic Dysphonia

This project will examine whether or not exercise performed immediately following botulinum toxin injection affects the clinical benefit received from the injection. This is a cross-over study and subjects will be randomly assigned to a group where they will speak continually for one hour or remain silent for one hour following injection. Data on the effectiveness of the exercise will be collected just before each injection and at 2 weeks, 6 weeks, and 3 months following injection.