stuttering or stammering, speech disorder marked by hesitation and inability to enunciate consonants without spasmodic repetition. Known technically as dysphemia, it has sometimes been attributed to an underlying personality disorder. About half of all those who have speech and voice defects suffer from stuttering or stammering (the terms are used interchangeably). In 65% of people who stutter, there is a family history of the disorder, thus suggesting a genetic link. Studies with twins have also indicated that inheritance has an important role in stuttering; comparing pairs in which at least one twin stuttered, it has been found that identical twins were much more likely to be stutterers than fraternal twins (see multiple birth). Brain scans of stutterers have found higher than normal activity in brain areas that coordinate conscious movement, suggesting that in people who stutter speech occurs less automatically than it does in most people.

In many instances the speech disturbance appears to be precipitated by such situations as a change of surroundings, the advent of a younger child in the family, or by a family environment in which parents are overly concerned with childhood speech interruptions, which occur normally. Negative reactions to the stuttering frequently create feelings of inadequacy and anxiety, which, in turn, intensify the condition. Parents with young children who stutter have been urged by specialists to help their children develop positive attitudes about themselves and their speech. Older stutterers are taught to understand what processes interfere with fluent speech and to speak without the disruptions caused by tension. Psychiatric treatment and group psychotherapy have been helpful for many.

or stammering or dysphemia

Speech defect affecting the rhythm and fluency of speech, with involuntary repetition of sounds or syllables and intermittent blocking or prolongation of sounds, syllables, and words. Stutterers consistently have trouble with words starting with consonants, first words in sentences, and multisyllable words. Stuttering has a psychological, not a physiological, basis, tending to appear in children pressured to speak fluently in public. In earlier times, stutterers were subjected to often torturous efforts to cure them. Today it is known that about 80percnt recover without treatment, usually by early adulthood. This probably results from increased self-esteem, acceptance of the problem, and consequent relaxation. Seealso speech therapy.

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