Stammering is characterised by stoppages and disruptions in fluency which interrupt the smooth flow and timing of speech.
These stoppages may take the form of repetitions of sounds, syllables or words, or of prolongations of sounds so that words seem to be stretched out, and can involve silent blocking of the airflow of speech when no sound is heard.
Speech may sound forced, tense or jerky. People who stammer may avoid certain words or situations which they know will cause them difficulty.
Some people avoid and substitute words to such an extent that people in their lives may not realise they have a stammer. This is known as "covert stammering".
It is not known what causes stammering but research seems to suggest that a combination of factors is involved.
Genetics are relevant at least in some cases. Someone with stammering in the family seems more likely to develop a stammer themselves.
Brain imaging studies have shown significant differences between the brain activity of people stammering as compared with fluent speakers.
Stammering affects people in different ways and can vary according to the situation in which the person finds themselves: to whom the person is talking; how they are feeling about themselves and their speech; and what they want to say.
Stammering can vary from adult to adult and child to child in its manner, frequency and severity.
Stammering is not simply a speech difficulty but is a serious communication problem.
For the child or adult who stammers it can undermine their confidence and self-esteem, and affect their interactions with others as well as their education and employment prospects.
Various factors have an effect on the ease or difficulty with which people who stammer can speak. These can include:
A child or adult who stammers may become more dysfluent when increased demands are made of the person in speaking situations, when the person has high expectations of him or herself in certain situations and with certain people (e.g. speaking on the telephone, at an interview) or when a specific response is needed (e.g. saying one's name, address or phone number, having to use particular words) . On the other hand, in some people this stress actually increases fluency.
Children or adults who stammer do so on words which carry information and when using complex words of several syllables. They tend to stammer more at the start of sentences.
Sometimes it is more difficult for people who stammer to speak fluently, for example when they are feeling ill, stressed, tired, excited, or upset.
People who stammer may become more dysfluent depending on: their feelings about their speech; their perceptions of themselves as effective communicators; and others' reactions to their stammering.
People who stammer are normally fluent when speaking in chorus, singing or whispering
It is widely accepted that 5% of children under the age of five will go through a phase of stammering at some stage in their speech and language development. Across the whole of Britain that represents around 188,000 pre-school age children. Up to a quarter of these children are at serious risk of developing chronic stammering which may persist into adulthood without intervention during the pre-school years. In the under fives twice as many boys stammer as girls.
From research studies it is estimated that 1.2% of all school-age children stammer. In the UK stammering affects approximately 109,000 children between the ages of 5-16 years old.
Figures on stammering in adulthood show that 1% of the adult population stammers - that's around 459,000 adults in Britain. About 3.5 to 4 men stammer for every woman who stammers.
Stammering does not appear to be increasing or decreasing. Published research studies indicate that these figures are consistent world-wide and that stammering occurs across all cultures and in all social groups
Some people seem to have a view that people who stammer are less intelligent, more nervous etc.
All research indicates that the stammering and the non-stammering populations are identical in terms of intelligence, mental state, neurotic behaviour etc. The only difference found is that one group stammers and the other doesn't, but no explanation for this has as yet been identified.
Speed of speech should not be confused with speed of thought. A person who stammers will generally think at normal speed, even though expression of the thoughts may be slower.
The BSA Parental Awareness Campaign promoted the message that children showing early signs of stammering should be referred to a speech and language therapist (SLT) as early as possible. Speech and language therapy has proved to be most effective with children aged under 5 years. In many cases when the problem is caught early enough (before psychological issues of anxiety and self consciousness arise) the child is able to learn to speak fluently again with no evidence of recurrence.
For both older children and adults who stammer, the situation is more complex. Modern therapy can help improve fluency, confidence and communication skills but as stammering is more established by this stage it becomes more a case of learning to manage it effectively. As well as speech and language therapy many people find self-help groups useful in this regard.
While speech and language therapy can continue to make a positive difference in older children and adults, there is no magical 'cure' for stammering.
Therapy to improve confidence and acceptance of a stammer can improve fluency- however it is important to be wary of those who claim to be able to cure your stammer for money.
Every person stammers differently, for different reasons and at different times. There is no one cure.
What has been found to be most effective is treatment under the age of 5 in terms of practising fluent speech, followed by group work and support for older children and adults.
"Stammering" is the same as "stuttering". "Stammering" is more often used in the UK and Ireland. "Stuttering" is usual in the United States.
Some people consider the phrase "person who stammers" (or PWS) or "child who stammers" to be preferable to "stammerer".
Stammering is something a person does. It is by no means the most important thing about the person, let alone who he or she is.
Whilst some people who stammer and others object to the term "stammerer", there are other people who stammer who are comfortable with the term and will commonly use it themselves.