Some 20 percent of all children go through a stage of development during which they encounter disfluencies severe enough to be a concern to their parents, according to the Stuttering Foundation.

"Myths persist through the years despite our efforts to demystify this complex disorder," Jane Fraser, president of the 60-year-old nonprofit organization Stuttering Foundation, said in a statement. "These myths create a negative perception of those who stutter and can harm their chances of success at school and in the workplace."

Many stuttering myths continue, including:

-- Myth: People who stutter are not smart, but the reality is there is no link between stuttering and intelligence.

-- Myth: Stuttering can be "caught" through imitation or by hearing another person stutter, but the reality is people can't "catch" stuttering and research indicates that family history, neurological development, a child's environment and family dynamics all play a role in the onset of stuttering.

-- Myth: Stress causes stuttering, but the reality is that while stress is not the cause, it can aggravate stuttering.