Stuttering, or stammering, is a speech disorder characterised by interruptions to speech such as hesitating, repeating sounds and words, or prolonging sounds. The cause of stuttering is unknown, but genetics are thought to play a significant role. Some children appear to recover from stuttering without any intervention, but a speech pathologist or the Lidcombe Program of Early Stuttering Intervention can help.
Stuttering, or stammering, is a speech disorder characterised by interruptions to speech such as hesitating, repeating sounds and words, or prolonging sounds. Around one per cent of people in all cultures stutter.
Stuttering can be mild, moderate or severe, and can vary within the same individual across speaking situations and from one day to the next, particularly with children.
Symptoms of stuttering
The symptoms vary widely between individuals, but can include:
- Hesitation, as if the next word is ‘stuck’
- Repeating sounds, syllables or words such as ‘I-I-I think’ or ‘where-where-where is it?’ and so on
- Prolonging sounds, such as ‘mmmm-mummy’.
Causes of stuttering
The cause is unknown, but researchers suspect that people who stutter have a slight ‘glitch’ in the brain connections responsible for speech production.
The fact that stuttering tends to run in families indicates that genetics is involved somehow in the condition. Studies of stuttering in twins have also found that both twins are more likely to stutter if they are identical rather than fraternal.
It was once assumed that parents, who mistakenly thought that their child had begun to stutter, caused a child’s stuttering. When children start to talk, they naturally hesitate and stumble over words. It was proposed that over-anxious parents believed this natural hesitation was stuttering, and pressured their child to talk properly, which caused the child to start ‘real’ stuttering. However, there is no evidence to indicate that anything parents do, or don’t do, can cause a child to stutter.
Effects of stuttering
Children who stutter are more likely to be teased by their peers. Older children and adults who stutter often fail to achieve their educational or career potential and may experience significant anxiety in social situations.
Development of stuttering
The progression of stuttering tends to follow the following pattern:
- Stuttering normally begins in children aged two to three years.
- Stuttering may develop gradually or suddenly.
- If stuttering is not treated in the preschool years, it starts to become difficult to treat in later years.
Degrees of severity
Stuttering is graded by its degree of severity. Most researchers rate stuttering by the percentage of stuttered syllables. While the child speaks, the speech pathologist counts all the stuttered and non-stuttered syllables. One classification method is:
- Mild – below five per cent of syllables stuttered
- Mild to moderate – 5 to 10 per cent of syllables stuttered
- Moderate – 10 to 15 per cent of syllables stuttered
- Moderate to severe – 15 to 20 per cent of syllables stuttered
- Severe – above 20 per cent of syllables stuttered.
Some children appear to recover from stuttering without any intervention. However, it is not possible to predict whether an individual child will recover. Parents should not be advised that their child will ‘grow out of’ stuttering. This will not be true in all cases, for if it were, there would be no such thing as stuttering in adulthood.
There are many problems in measuring the actual rate of natural recovery – estimates have ranged from 30 to 90 per cent of cases. Several recent estimates have been around the 75 per cent mark, but these were population estimates and they cannot be applied to children who come to a clinic for treatment. For reasons unknown, boys seem to be less likely to recover naturally than girls.
Seek professional help
Parents should always seek professional help from a speech pathologist if their child begins to stutter. The speech pathologist will determine whether treatment should occur immediately or whether it is better to wait a while to see if natural recovery occurs. Stuttering children should always be treated at some time during the preschool years.
Treatment for children
The best evidence (from clinical trials) for treating children who stutter is the Lidcombe Program of Early Stuttering Intervention. This is a behaviour modification treatment. The main principles involve praising a child when words are spoken clearly, and occasionally noting when stuttering has occurred.
It’s essential for parents to be trained in the Lidcombe technique to ensure they know how to comment positively about their child’s speech (rather than the child’s behaviour). If parents and carers receive proper training, there is no evidence that correcting a child’s speech will cause the child to become stressed or anxious. In fact, research has shown that the Lidcombe program causes no such adverse psychological events.
Treatment for adults
Treatment for stuttering is much more effective in the preschool years, but treatment for older children, adolescents and adults is effective as well. The best evidence available supports the use of a technique called ‘prolonged speech’ or ‘smooth speech,’ where the person’s speech pattern is reconstructed.
Where to get help
- Speech pathologist
- Your school nurse for referral
- Your local community health centre
Things to remember
- Stuttering, or stammering, is a speech disorder characterised by interruptions to speech such as hesitating, repeating sounds and words, or prolonging sounds.
- The cause of stuttering is unknown, but genetics are thought to play a significant role.
- Children and adults who stutter can benefit from speech therapy.
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This page has been produced in consultation with and approved by:
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The Australian Stuttering Research Centre
Fact sheet currently being reviewed.
Last reviewed: May 2012
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