For people who stutter, words do not always come easily.

The speech disorder, whose symptoms include repeating or prolonging initial sounds, can cause frustration, isolation and, for some, a reluctance to speak at all.

The “declaration of people who stutter,” adopted in Japan 50 years ago by a self-help group, asserted that stuttering could not be cured and called on people with the condition to find a way to live with it.