Stammering – also sometimes referred to as stuttering – is a relatively common speech problem in childhood, which can persist into adulthood.

What is stammering?

Stammering is when:

  • you repeat sounds or syllables – for example, such as saying "mu-mu-mu-mummy"
  • you make sounds longer – for example, "mmmmmmummy"
  • a word gets stuck or doesn't come out at all

Stammering varies in severity from person to person, and from situation to situation. Someone might have periods of stammering followed by times when they speak relatively fluently.

Read more about how stammering can affect you.

Types of stammering

There are two main types of stammering. They're known as:

  • developmental stammering – the most common type of stammering; it occurs in early childhood when speech and language skills are developing rapidly
  • acquired or late-onset stammering – is relatively rare and occurs in older children and adults as a result of a head injury, stroke or a progressive neurological condition; it can also be caused by certain drugs or medication, or psychological or emotional trauma

This topic focuses on developmental stammering.

What causes stammering?

It isn't possible to say for sure why a particular child starts stammering, but it isn't caused by anything the parents have done.

Developmental and inherited factors may play a part, along with small differences in how efficiently the speech areas of the brain are working.

Speech development

Speech development is a complex process that involves communication between different areas of the brain, and between the brain and the muscles responsible for breathing and speaking.

When every part of this system works well, the right words are spoken in the right order, with correct rhythm, pauses and emphasis.

A child learning to construct simple sentences needs practise to develop the different speech areas in the brain and lay down the neural pathways ("wiring") needed for the different parts to work well together.

Talking problems can occur if some parts of this developing system aren't quite co-ordinated. This can cause repetitions and stoppages, particularly when the child has lots to say, is excited, or feeling under pressure.

As the brain continues to develop, some of these problems resolve or the brain is able to compensate, which is why many children "grow out" of stammering.

Sex differences and genes

Stammering is more common in boys than in girls.  It is unclear why this is.

Genes are also thought to have a role.  Around 2 in 3 people who stammer have a family history of stammering, which suggests the genes a child inherits from their parents might make them more likely to develop a stammer.

When to get help

You should get advice if you have any concerns about your child's speech or language development.

Treatment for stammering is often successful in pre-school age children, so it's important to get referred to a specialist as soon as possible.

Talk to a GP or health visitor to discuss your concerns with them. If necessary, they may refer your child to a speech and language therapist (SLT) for an assessment.

In many areas, you can phone the children's speech and language services directly and refer your child yourself.

Stamma (The British Stammering Association) has more information and advice for parents.  You can call the helpline on 0808 802 0002 from Monday to Friday 10am to midday and 6pm to 8pm to find out about the services available in your area.

If you're an adult who stammers and it's having a significant impact on your social and work life, you may want to ask your GP to refer you to an SLT.

Treatments for stammering

There are different speech and language therapy approaches that can help people who stammer speak more easily.

You'll work together with a therapist to come up with a suitable plan tailored to you or your child.

This may involve:

  • creating an environment where your child feels more relaxed and confident about talking
  • strategies to increase fluency and develop communication skills
  • working on feelings associated with stammering, such as fear and anxiety

Electronic devices to reduce stammering are also available and can help some older children and adults, but they're not usually available on the NHS.

Read more about treating stammering.

Who's affected

Studies suggest around 1 in 20 young children go through a phase of stammering.

Around 2 in 3 children who stammer grow out of it, although it's difficult to predict when this will happen in a particular child.

It's estimated that stammering affects around 1 in 100 adults, with men being around 3-4 times more likely to stammer than women.

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Problems usually become apparent while your child is still learning to speak, between the ages of two and five.

As a child gets older and becomes more aware of their stammering, they may also change their behaviour in certain ways to hide their speech difficulties.

Stammering may develop gradually, although it often starts suddenly in a child who has previously been talking well.

Typical features

Stammering can involve:

  • repeating certain sounds, syllables or words when speaking, such as saying "a-a-a-a-apple" instead of "apple"
  • prolonging certain sounds and not being able to move on to the next sound – for example, saying "mmmmmmmilk"
  • lengthy pauses between certain sounds and words, which can seem as though a child is struggling to get the right word, phrase or sentence out
  • using a lot of "filler" words during speech, such as "um" and "ah"
  • avoiding eye contact with other people while struggling with sounds or words

Stammering is also more likely when a young child has a lot to say, is excited, saying something important to them, or wants to ask a question.

Stammering can be worse in situations where the child is self-conscious about their speech and so may be trying hard not to stammer.

These situations might include:

  • talking to a person in authority, such as a teacher
  • saying something in front of the class
  • reading aloud
  • speaking on the telephone
  • saying their name in registration at school

Behaviours associated with stammering 

A child who stammers can also develop involuntary movements like eye blinking, quivering lips, grimacing, tapping the fingers or stamping the feet.

They may also:

  • deliberately avoid saying certain sounds or words that they typically stammer on
  • adopt strategies to hide their stammering, such as claiming to have forgotten what they were trying to say when they have trouble getting words out smoothly
  • avoid social situations because of a fear of stammering, such as not asking for items in shops or going to birthday parties
  • change the style of speech to prevent stammering – for example, talking very slowly or softly, or speaking with an accent
  • feel fear, frustration, shame or embarrassment because of their stammering

When to get help

If you have concerns about your child's speech or language development, talk to a GP, health visitor, or a speech and language therapist.

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There are different treatments available for stammering, depending on a person's age and their circumstances.

A speech and language therapist (SLT) will work with you, your child, and educational staff to come up with a suitable treatment plan for your child.

An SLT can also work with adults who stammer to help find ways to improve the fluency of their speech and reduce the impact stammering has on their lives.

You may be able to access psychological therapy to help with any emotional problems linked to your speech difficulties.

Speech and language therapy is widely available on the NHS for people who stammer, although the level of service and waiting times vary across the country. Some treatments, such as feedback devices, may not be funded.

If you're aged 18 or older and cannot get therapy in your area, Stamma (The British Stammering Association) offers speech therapy via a video call using Skype or Facetime).

Indirect therapy

Indirect therapy is where parents make changes to the way they communicate and the home environment, rather than focusing directly on the child's talking.

If your child is under five, this is probably the approach your therapist will suggest you try first.

However, if a young child has been stammering for several months and it seems to be getting more severe, it may be best to start direct therapy straight away.

Indirect approaches are often based on the concept that children start to stammer when they can't keep up with the demands made on their language skills.

These "demands" may come from other people around them or from the child's own enthusiasm and determination to communicate.

The goal of indirect therapy is to create an environment where the child feels less pressure when speaking.

This may involve:

  • speaking slowly and calmly to the child
  • encouraging turn-taking and listening within the family
  • doing more of what seems to help the child's fluency – for example, chatting about what you and your child are doing together, such as playing, cooking, walking to pre-school, or looking at favourite books
  • avoiding interrupting or criticising the child
  • making the family environment as relaxing and calm as possible

Direct therapy:

Younger children

The Lidcombe Program is a widely used direct behavioural therapy for the treatment of stammering in young children.

It's designed to be carried out by the child's parents under the guidance of a speech and language therapist.

The programme is based on the principle of providing consistent feedback to the child about their speech in a friendly, non-judgemental and supportive way.

The Speech Disorder website has more information about the Lidcombe Program.

Older children

Stammering that persists beyond the age of six or has lasted for more than three years is significantly more challenging to treat.

As time passes, the effects of stammering become an additional part of the problem. These include anxiety about speaking, fear of stammering, and feelings of embarrassment.

Therapy with older children and adults will often take account of both the speaking behaviours and the social, emotional and psychological aspects of stammering.

With school-age children, direct therapy is often used to:

  • help improve fluency
  • help the child understand more about stammering
  • share experiences with others who stammer
  • work on feelings associated with stammering, such as fear and anxiety
  • improve communication skills
  • develop self-confidence and positive attitudes

Other treatment options

In addition to direct and indirect therapy, there are other options that can help people who stammer, particularly older children and adults with persistent stammering and those who develop stammering later in life (acquired or late-onset stammering).

Psychological therapies

These include solution-focused brief therapy (SFBT), personal construct therapy, neurolinguistic programming (NLP) and cognitive behavioural therapy (CBT).

These therapies don't treat stammering directly, but can be helpful if you experience negative feelings as a result of your stammering.

Feedback devices

Feedback devices alter the way you hear your own voice. They include:

  • delayed auditory feedback (DAF) – these play your voice back to you a fraction of a second after speaking
  • frequency-shifted auditory feedback (FSAF) – these play your voice back to you at a lower or higher frequency
  • combined DAF/FSAF devices – these use a combination of both methods mentioned above

These devices are often fitted inside or around the ear, similar to a hearing aid, and can help improve the fluency of some people's speech. There are also apps for smartphones and computers that work in a similar way.

These techniques don't work for everyone and can be difficult to use in some speaking situations. The devices aren't generally available on the NHS.

You can read more about electronic devices and apps on the Stamma.

Speaking to someone who stammers

When talking to someone who stammers, try to:

  • avoid finishing their sentences if they're struggling to get their words out
  • give them enough time to finish what they're saying without interrupting
  • avoid asking them to speak faster or more slowly
  • show interest in what they're saying, not how they're saying it, and maintain eye contact

Speak slowly and calmly when talking to a young child who stammers. Use short sentences and simple language to reduce the communication demands on the child.

Don't overwhelm your child by talking too quickly. Make sure you give them time to understand and process what you've said, and work out their response.

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The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website nhs.uk
Last Updated: 06/05/2020 09:49:04