Nikki,SD is the most rare and severe vocal disorder, and is the only vocal disorder which is neurological.
Just because someone sounds bad (sometimes really bad) doesn't mean they have SD.
A professional singer is much more likely to have many functional vocal conditions related to the high demands on their larynx. Such as nodes or MTD or a number of other things which are not neurological.
Mid-way through my research (15 years worth) to discover what was wrong with my voice, I encountered information which, bottom-line, said, "every larynx has its limit."
Vocal performers often stress their laryngeal-instrument WAY beyond what their bodies can handle. For professional performers, high-quality vocal training is an absolute necessity in order to preserve the vocal instrument.
For the rest of us, who had to talk 10 hours a day to do our jobs, the voice is absolutely necessary but (believe it or not) not as stressful to the larynx as being a professional performer at the Met, or wherever.
The greatest singers have a very strong and powerful vocal instrument. The best ones are born with a strong laryngeal instrument, and learn how to use it properly with training. The rest of us don't, even though some of the folks with less powerful larynx's sing also, even though they don't sound like a Metropolitan Opera Star.
Also, keep in mind that many people posting on this BB do not have SD. SD is in the "rare and severe" category of vocal disorders (even though SD itself runs the gamut from mild to very severe).
Just because a voice sounds really bad does not mean it's a neurological laryngeal vocal disorder. Spasmodic Dysphonia. We are rare --- and special.
--Lynne (AD-SD; RLN; PVFM; Northern California)
