Stuttering (Stammering)

What stuttering is

Everyone has some disfluencies, such as "um" or repeating a phrase. Stuttering is different in its type and frequency. Typical stuttering behaviors are:

• Repetitions of sounds, syllables or one-syllable words: "m-m-my", "ba-ba-baby"
• Prolongations: stretching a sound: "ssssee"
• Blocks: getting stuck with no sound coming out, often with visible tension

Many people who stutter also develop secondary behaviors: eye blinking, head jerks, swapping words, adding filler words, or avoiding speaking situations. Feelings of frustration, embarrassment or anxiety about speaking often build over time and can be as limiting as the stutter itself.

Stuttering typically varies. It is often worse when tired, excited, under time pressure, saying your name or using the phone, and usually disappears when singing, speaking in unison or talking to a pet.

Types of stuttering

Causes and risk factors

Developmental stuttering is a neurological condition. Brain imaging shows differences in the networks that plan and time speech movements, especially in the left hemisphere and basal ganglia.

• Genetics: about 2 in 3 people who stutter have a relative who does. Specific genes, such as GNPTAB, have been identified in some families.
• Sex: boys are 2 to 3 times more likely to stutter, and much more likely to continue into adulthood.
• Age at onset: starting after 3 and a half makes persistence more likely.
• Duration: stuttering lasting more than 6 to 12 months is less likely to resolve on its own.
• Other speech or language difficulties.

Stuttering is not caused by parenting, a traumatic event, low intelligence or nervousness. Stress can make it worse but does not create it.

Stuttering in children: what is normal?

Many toddlers go through a phase of normal disfluency as their language grows rapidly. Stuttering is separate from a general speech delay, although the two can occur together.

About 75 to 80% of children who start stuttering stop within 2 years, many without therapy. Because it is hard to predict who will recover, a referral to a speech-language pathologist is recommended if any warning signs are present.

How parents can help

• Speak slowly and calmly yourself, with pauses.
• Give your full attention and wait for your child to finish; do not finish their words.
• Avoid saying "slow down", "relax" or "take a breath", which add pressure.
• Reduce questions and time pressure; take turns talking at family meals.
• Talk about stuttering openly and kindly if your child notices it.
• Praise what they say, not how smoothly they say it.

Stuttering in adults

Around 1% of adults stutter, most since childhood. Many adults also experience anxiety about speaking, and up to half of adults who seek help for stuttering meet criteria for social anxiety disorder.

Sudden stuttering in an adult without a childhood history needs medical assessment. It can be a sign of a stroke, brain injury, Parkinson's disease, a medicine side effect or another neurological problem.

Diagnosis

A speech-language pathologist (SLP) assesses stuttering by:

• recording speech in different situations and measuring the frequency and type of disfluencies
• rating severity and secondary behaviors
• asking about onset, family history and impact
• assessing the person's feelings and attitudes about speaking
• checking other speech and language skills, since stuttering can coexist with other speech disorders

Neurogenic stuttering may also need a neurologist and brain imaging. Repeated involuntary sounds or words can also be vocal tics, as in Tourette syndrome, which a specialist can distinguish from stuttering.

Treatment

There is no cure, but therapy helps most people speak more fluently and confidently.

Young children

• Lidcombe Program: a parent-delivered program for children under 6, trained and supervised by an SLP. Parents give positive comments for smooth speech and occasionally ask for self-correction of stuttered words.
• Palin Parent-Child Interaction therapy: adjusts family communication styles to support fluency.
• RESTART-DCM: reduces demands on speech while building capacity.

School-age children, teens and adults

• Fluency shaping: learning a new speaking pattern with slower speech, gentle voice onsets, soft consonant contacts and continuous airflow, then gradually returning to natural speed.
• Stuttering modification: reducing fear and avoidance, and learning to stutter more easily and with less tension.
• Cognitive behavioral therapy (CBT) for speech anxiety and avoidance.
• Self-help and support groups, which reduce isolation and build confidence.
• Electronic devices that play back altered auditory feedback can help some people temporarily.

No medicine is approved for stuttering. Some drugs have been studied, but none is recommended as a routine treatment.

Outlook

Most children who stutter recover, especially girls and those whose stuttering starts early and settles within a year. For those whose stuttering persists, therapy can greatly reduce its severity and impact. Many adults who stutter lead full professional and social lives, and acceptance of stuttering is increasingly part of treatment.

Frequently asked questions

What causes stuttering?

Developmental stuttering is caused by differences in how the brain plans and coordinates speech, with a strong genetic component. It runs in families. It is not caused by parenting, nervousness or trauma, though stress and fatigue can make it worse.

Will my child grow out of stuttering?

Probably. About 75 to 80% of young children who stutter stop within a couple of years. Recovery is less likely if stuttering has lasted more than 6 to 12 months, started after age 3 and a half, the child is a boy, or a relative still stutters. See a speech therapist if in doubt.

How can I stop stuttering as an adult?

Speech therapy with a speech-language pathologist who specializes in fluency is the most effective approach. Techniques such as slower, smoother speech and easy onsets help control stuttering, and CBT reduces speaking anxiety. Support groups and practicing in real situations build confidence.

Why do people not stutter when they sing?

Singing uses rhythm, a steady beat and stretched vowels, and it relies on different brain timing networks than spontaneous speech. Speaking in unison or with a metronome has a similar effect. Some fluency techniques borrow these features.

Can anxiety cause stuttering?

Anxiety does not cause developmental stuttering, but stuttering can lead to anxiety about speaking, and anxiety can make stuttering worse. Treating both together often gives the best results. Sudden stuttering in adults should be checked medically rather than assumed to be anxiety.