One in twenty children stutters, speaking with noticeable disfluencies that interfere with communication. These disfluencies can take the form of repeating sounds, prolonging sounds, or just unnatural pauses between syllables and words. Often it’s just an ordinary part of learning how to speak, but for roughly one percent of children, stuttering is a lifelong problem.
Although it’s not clear what causes stuttering, there’s some evidence of a genetic cause, and it’s been observed to run in families, with about three in five stutterers having a relative who stutters—the writer and television presenter Dominick Dunne and his brother, the novelist and critic John Gregory Dunne both had trouble with stuttering.
It has been found that the brains of people who stutter process language differently than those of other people. Sometimes people who did not previously exhibit disfluencies start to stutter after a stroke or brain trauma. Most likely, a combination of factors influences stuttering.
Beyond biological causes, there is also a psychological aspect. Stuttering isn’t a mental disorder, but people who grew up in high-pressure family environments often show signs of strain. Stuttering can be one of those signs. In very rare cases, emotional trauma or mental or intellectual problems can manifest themselves as what’s called psychogenic stuttering; however, only a tiny percentage of actual cases of stuttering are psychogenic.
There is currently no cure for stuttering, though when it can be traced to an underlying cause, if the cause is treatable, treating it often also treats the stuttering. In the case of children who stutter, time is usually sufficient to treat it. Anti-stuttering applications are an off-label—unofficial—use of some medications, but most treatment focuses on developing strategies to minimize or disguise the disfluencies.