Also known as stammering, stuttering is generally not a problem with the physical production of speech or putting thoughts into words. It’s a disorder in which the flow of speech is disrupted by an involuntary repetition, drawing out, or block in producing a sound or syllable, such as saying ‘mi-mi-mi-milk’ or ‘mmmmmmilk’, or pausing before speaking, which prevents sounds getting out at all.

Types of stutterers

There are two main types of stutterers; the overt stutterer who openly struggles with word after word as they speak, and the covert stutterer who goes to considerable lengths to avoid certain words and situations, rather than be identified as a stutterer.

Three types of stuttering

• Developmental stuttering

  By far the most common, developmental stuttering happens in early childhood when speech and language skills are developing. A child learning to construct simple sentences needs practice to develop the different speech areas in the brain and create the neural pathways needed for the different parts to work in unison. When every part of this system works well, the right words are spoken in the right order, with the correct rhythm, pauses, and emphasis. However, if some parts of this developing system are not fully co-ordinated, speech problems can occur, particularly when the child is excited or feels under pressure. Stuttering typically presents between the ages of two and four, affecting around 5% of children. At this age, most are unaware of the interruptions in their speech, and as their brains continue to develop, many will ‘grow out’ of stuttering within a matter of months. Unfortunately, the remaining 1% of the population (around 70 million people worldwide) will have a long-term problem that will continue into adulthood, and of these, men will outnumber women by a ratio of 4:1.

• Acquired stuttering

  In rare cases, stuttering may be acquired by older children or adults as a consequence of a neurological event such as a head injury, tumour, stroke, progressive condition, or drug use. It can also arise after a psychological or emotional trauma such as grief or a relationship breakdown.

• Neurogenic stuttering

  Stuttering can also develop following injury or disease to the central nervous system such as the brain or spinal cord. A person with neurogenic stuttering finds it difficult to speak in a normal, smooth fashion and may have speech that sounds fragmented or halting, with frequent pauses.

What is the cause of developmental stuttering?

Although the exact cause of developmental stuttering is unknown, inherited factors may play a part, along with small differences in how efficiently the speech areas of the brain are working.

• Children who have first-degree relatives who stutter are three times as likely to develop one themselves. However, there are also many people who stutter, who have no family history of the disorder, and research involving twins and adopted children suggests that genetic factors alone aren’t responsible.

• There is evidence that stuttering is more common in children who also have simultaneous speech, language, learning or motor difficulties

• Evidence also suggests that certain cases of stuttering could be due to autoimmune disorders associated with streptococcus infections in childhood, whereby antibodies directed against the infection cross-react and attack the developing basal ganglia in the brain

• Another view is that a stutter is a complex tic, the cause of which is generally stress, anxiety, tiredness, or excitement. Tics are fast, repetitive muscle movements that result in sudden and difficult to control body movements or sounds. The more tense the child, the more they use the tic as an outlet for their tension, and those children struggling with a sound repetition may eventually develop a stutter. 

• Around 2.5% of children under the age of five stutter, and at this age the number of boys and girls is roughly equal. However, girls have a higher recovery rate, which, according to neuroimaging studies, is because their brain developmental issues are less pronounced. Another explanation is that during childhood the Hypothalamic-Pituitary-Adrenal (HPA) Axis produces more cortisol in boys than girls, which has the effect of making boys more tense and anxious by comparison, and increases their susceptibility to repetitive behaviours.

• A study of brain scans of adults who stutter, compared with those who don’t, shows that adults who stutter display less activation of the left hemisphere (which is associated with speech), and increased activation of the right hemisphere (which is associated with emotions). There are also differences in the size of some areas of the brain, and the positioning of white and grey matter tissue. However, the research is complicated somewhat by the possibility that these differences could be the consequences of stuttering, rather than a cause.

• Most people who develop a stutter can speak without stuttering when they talk to themselves, and when they sing or speak in unison with someone else.

What are the effects on feelings and behaviour?

Children who continue to stutter beyond their early years may shift from easy, relaxed repetition to more tense and self-conscious stuttering. Advice to "slow down", "take a breath", and "say it again" by parents, siblings and teachers may inadvertently draw attention to the behaviour and increase the child’s awareness of it. Over time secondary stuttering, including behaviours such as eye blinking, lip movements, grimacing, tapping their fingers or stamping their feet may develop. They may adopt strategies to try to hide their stammering such as avoiding certain words or sounds, changing their style of speech by talking slowly or softly, or avoiding social situations such as family gatherings and birthday parties. Eventually, many become fully aware of their disorder and begin to identify themselves as stutterers, and with this may come feelings of fear, frustration, shame and embarrassment.

Is stress a factor?

Acute stress is not thought to cause stuttering, but people living with a speech disorder often develop chronic anxiety because of the nature of their disability, which can develop into a cycle known as positive feedback. That is, A produces more of B, which in turn produces more of A.

What are the other effects of having a stutter?

Over time, continued exposure to difficult speaking experiences may crystallize into a negative self-image and social anxiety, which, unless tackled in its early stages, can blight future career prospects and personal relationships, and is associated with a lower overall quality of life. Adults who stutter have a twofold increase in mood disorders, and a threefold increase in personality disorders when compared to the general population.

What treatments are available?

Speech therapy

The Lidcombe Programme is a widely used behavioural therapy for young children that’s used by the child's parents/carers under the guidance of a speech and language therapist, which encourages them to provide feedback to the child about their speech in a friendly, non-judgemental and supportive way. Therapy for older children and adults often takes account of the social, emotional and psychological aspects of stuttering, as well as their speech, and is directed toward improving the speaker's attitudes toward communication, and minimizing the negative impact stuttering can have on their life. Unfortunately, because covert stutterers appear to stutter only occasionally, they may get less help and be given fewer tools to manage their disfluency, than those whose stuttering is more obvious. Several treatment options exist:

• Fluency shaping therapy: Training people who stutter to reduce their speaking rate by stretching vowels and consonants, and controlling their breathing and articulation. The result is very slow, monotonic, but fluent speech, which gradually increases with practice.

• Modification therapy: The goal of stuttering modification therapy is not to eliminate stuttering but to modify it so that stuttering is easier and less effortful. The belief is that since fear and anxiety causes increased stuttering, by making stuttering easier, with less fear and avoidance, the stuttering will decrease.

• Auditory feedback devices: Altered auditory feedback methods, whereby people who stutter hear their voice differently, work by blocking out the stutterer’s voice while talking (masking), by altering the frequency of the feedback (frequency altered feedback), or by having them speaking in chorus with another person. These devices often fit inside or around the ear, similar to a hearing aid, and can help improve fluency. There are also apps for smartphones and computers that work in a similar way, enabling users to interact with the application by speaking into the headset's microphone, and then listening back to it through the headphones.

• Rhythm: Metronomes and tempo correctors can help to regulate speech, especially when pronouncing slowly.

• Visual feedback devices: This method enables the user to see a visual representation of their speech on the screen, and to track their progress.

• Breathing techniques: Stuttering is associated with various airflow irregularities, particularly the tightening of the laryngeal muscles in the throat, causing a lack of oxygen in the lungs. Modifying breathing behaviour can be beneficial in these circumstances.

• Regulated breathing: A behavioural treatment that consists of several different components including awareness training, relaxation, competing response training, motivation training, and generalisation training.

• Diaphragmatic breathing: Also known as costal breathing, the two major programmes which teach this technique are the McGuire Programme and the Starfish Project.

Psychological approaches

Psychological therapies commonly used in therapy for stuttering include:

• Cognitive Behaviour Therapy (CBT): Teaches several skills to help manage challenging situations, such as how to cultivate more positive, helpful perspectives, and develop problem-solving abilities.

• Solution Focused Brief Therapy (SFBT): Helps to identify clear, practical, realistic solutions to achieve goals.

• Acceptance and Commitment Therapy (ACT): Teaches mindfulness skills as well as ways to let go of unhelpful patterns of thinking.

• Hypnotherapy: Hypnosis can improve fluency by reducing stress and anxiety, building self-confidence, and reinforcing strategies to cope with day-to-day triggers.

Medications

Elevated dopamine levels are associated with stuttering, and antipsychotic medications, which have a dopamine blocking action, have been used as a treatment for a number of years. However, the side effects of these drugs such as weight gain, depression, and Parkinson-like movement disorders, often results in poor long-term compliance. More recently, trials of a medication called Ecopipam, which also blocks dopamine, but in a slightly different way, has demonstrated significantly improved stuttering symptoms without the side-effects, and is showing promise as an effective treatment. Read more about the research here:

Neuromodulation

• Transcranial Direct Current Stimulation (tDCS): Brain stimulation, known tDCS, involves applying electrodes to each temple and then passing an electric current through the head. The current is weak enough that people are either oblivious to the electrodes being switched on, or feel just a slight tingling. Each time a neuron fires in the brain, its connections with neighbouring neurons are strengthened or weakened slightly, which is how learning occurs. However, when stimulation is applied, the threshold for neurons firing is lower, which researchers believe may accelerate the rewiring that occurs during fluency training. Read about a recent trial here.

• Repetitive Transcranial Magnetic Stimulation (rTMS): Another form of neuromodulation that alters the brain’s electrical activity with large magnets oriented outside the skull, rTMS is also being investigated as a possible treatment for stuttering. Read about a recent trial here.  

Connecting with other people who stutter

Support groups can be a good source of tips and advice, and perhaps most importantly, understanding and encouragement. Here are some links to useful organisations in the UK;

https://westutter.org

https://stamma.org

http://www.speechdisorder.co.uk

https://michaelpalincentreforstammering.org

Speaking to someone who stutters

When in conversation with someone who stutters, 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.

Thank you for reading this blog post. If you have any thoughts to share, or ideas for future posts, please do let me know. I would love to hear from you.