What is Stuttering
Stuttering is a speech disorder in which the normal flow of speech
is disrupted by frequent repetitions or prolongations of speech sounds,
syllables or words or by an individual's inability to start a word.
The speech disruptions may be accompanied by rapid eye blinks, tremors
of the lips and/or jaw or other struggle behaviors of the face or upper
body that a person who stutters may use in an attempt to speak. Certain
situations, such as speaking before a group of people or talking on
the telephone, tend to make stuttering more severe, whereas other situations,
such as singing or speaking alone, often improve fluency.
Stuttering may also be referred to as stammering, especially in England,
and by a broader term, disfluent speech. Stuttering is different from
two additional speech fluency disorders, cluttering, characterized by
a rapid, irregular speech and spasmodic dysphonia, a voice disorder.
How is speech normally produced?
Speech is normally produced through a series of precisely coordinated
muscle movements involving respiration (the breathing mechanism), phonation
(the voicing mechanism) and articulation (throat, palate, tongue, lips
and teeth). These muscle movements are initiated, coordinated and controlled
by the brain and monitored through the senses of hearing and touch.
Before speaking, an individual takes a breath and the vocal folds (or
vocal cords), which are two bands of muscular tissue located in the
voice box directly above the trachea or windpipe, must come together.
The air that is held in the lungs is gradually released, passing through
the gently closed vocal folds thus causing vibration and producing the
voice. The sound of the voice is passed through the throat and is directed
into the mouth for most speech sounds, or into the nose for nasal sounds
such as "m," "n" and "ng." The palate,
tongue, jaw and lips move in precise ways to modify the sounds in order
to make speech sounds
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Who stutters?
It is estimated that over three million Americans stutter. Stuttering
affects individuals of all ages but occurs most frequently in young
children between the ages of 2 and 6 who are developing language. Boys
are three times more likely to stutter than girls. Most children, however,
outgrow their stuttering, and it is estimated that less than 1 percent
of adults stutter.
Many individuals who stutter have become successful in careers that
require public speaking. The list of individuals includes Winston Churchill,
actress Marilyn Monroe, actors James Earl Jones, Bruce Willis and Jimmy
Stewart, and singers Carly Simon and Mel Tillis, to name only a few.
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What causes stuttering?
Scientists suspect a variety of causes. There is reason to believe
that many forms of stuttering are genetically determined. The precise
mechanisms causing stuttering are not understood.
The most common form of stuttering is thought to be developmental,
that is, it is occurring in children who are in the process of developing
speech and language. This relaxed type of stuttering is felt to occur
when a child's speech and language abilities are unable to meet his
or her verbal demands. Stuttering happens when the child searches for
the correct word. Developmental stuttering is usually outgrown.
Another common form of stuttering is neurogenic. Neurogenic disorders
arise from signal problems between the brain and nerves or muscles.
In neurogenic stuttering, the brain is unable to coordinate adequately
the different components of the speech mechanism. Neurogenic stuttering
may also occur following a stroke or other type of brain injury.
Other forms of stuttering are classified as psychogenic or originating
in the mind or mental activity of the brain such as thought and reasoning.
Whereas at one time the major cause of stuttering was thought to be
psychogenic, this type of stuttering is now known to account for only
a minority of the individuals who stutter.
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