Onset and Development

Like most other speech disorders, stuttering begins in early childhood, when a child is first developing his or her speech and language skills. The vast majority of stutters develop between the ages of two and five, with many stutterers outgrowing their stutter before adolescence. Most stutters manifest before the age of 7, although there have been rare cases of a stutter developing later. Almost all children go through a stage of disfluency in early speech, but when a child displays signs of a serious stutter, it is wise to seek professional help because stutters are much easier to prevent or lessen in their early stages. Stuttering can become a serious disability, and an untreated stutter usually becomes worse with time. For a developing child, a stutter can cause lower self-esteem and can increase anxiety and stress, all of which serve to worsen a stutter. Stutters can and often do hamper social development and limit educational and professional opportunities.

As speech and language are difficult and complex skills to learn, almost all children have some difficulty in developing these skills. This results in normal disfluencies that tend to be single-syllable, whole-word or phrase repetitions, interjections, brief pauses, or revisions. In the early years, a child will not usually exhibit visible tension, frustration or anxiety when speaking disfluently and most will be unaware of the interruptions in their speech. With young stutterers, their disfluency tends to be episodic, and periods of stuttering are followed by periods of relative fluency. This pattern remains through all stages of a stutter's development, but as the stutter develops, the disfluencies tend to develop more into repetitions and sound prolongations, often combined together (e.g., "Lllllets g-g-go there").

Usually by the age of 6, a stutter is exacerbated when the child is excited, upset or under some type of pressure. Also around this age, a child will start to become aware of problems in his or her speech. After this age, stuttering includes repetitions, prolongations, and blocks. It also becomes more and more chronic, with longer periods of disfluency. Secondary motor behaviors (eye blinking, lip movements, etc.) may be used during moments of stuttering or frustration. Also, fear and avoidance of sounds, words, people, or speaking situations usually begin at this time, along with feelings of embarrassment and shame. By age 14 , the stutter is usually classified as an "Advanced stutter," characterized by frequent and noticeable interruptions, with poor eye contact and the use of various tricks to disguise the stuttering. Along with a mature stutter come advanced feelings of fear and increasingly frequent avoidance of unfavorable speaking situations. Around this time many become fully aware of their disorder and begin to identify themselves as "stutterers." With this may come deeper frustration, embarrassment and shame.

It is important to note that stuttering does not affect intelligence and that stutterers are sometimes wrongly perceived as being less intelligent than non-stutterers. This is mainly due to the fact that stutterers often resort to a practice called word substitution, where words that are difficult for a stutterer to speak are replaced with less-suitable words that are easier to pronounce. This often leads to awkward sentences which give an impression of feeble mindedness. Stuttering is a communicative disorder that affects speech; it is not a language disorder—although a person's use of language is often affected or limited by a stutter.