Understanding Stuttering

National Stuttering Association
Aug 7, 2024
6 min read

Updated: Oct 14

What Is Stuttering?

Stuttering is a natural variation in speech in which the timing and flow of spoken language include moments of repetition, prolongation, or blocking of sounds and words. These moments are simply examples of the many ways humans produce speech.

Commonly Observed Features

Repetitions – repeating sounds, syllables, or words (e.g., “I-I-I want to go”).
Prolongations – stretching out a sound (e.g., “ssssun”).
Blocks – pauses where speech momentarily stops, usually with a build up of internal and/or external muscle tension, even when the speaker knows what they want to say.

These variations may occur more often when someone is excited, tired, feeling pressure to speak quickly, or navigating certain environments (NIDCD, 2023).

Stuttering is not only about what can be heard—it can also involve:

Physical movements like eye blinks, facial tension, or shifts in posture that may accompany moments of stuttering (ASHA, n.d.).
Feelings and thoughts about speaking, shaped by personal experiences and societal attitudes. Some people who stutter feel comfortable and confident speaking; others may experience anxiety or frustration in unsupportive contexts (ASHA, n.d.).
Communication choices such as word substitutions or avoiding certain situations—often not because of stuttering itself, but because of how others may respond to it (Tichenor & Yaruss, 2019).

Varieties of Stuttering

While every person’s speech is unique, stuttering may be described in terms of how and when it begins:

Childhood-Onset Stuttering – often begins between ages 2–5 during speech and language development (Yairi & Ambrose, 2013).
Neurogenic Stuttering – may appear after neurological changes such as brain injury or stroke (Theys et al., 2024).
Functional Stuttering – rare, and often linked to psychological or emotional events (NIH, n.d.).

What Causes Stuttering?

The precise causes of stuttering are still unknown, but most researchers now consider stuttering to involve differences in brain activity that interfere with the production of speech. In some people, the tendency to stutter may be inherited. Although the interference with speech is sometimes triggered by emotional or situational factors, stuttering is basically neurological and physiological – not psychological – in nature.

Research points to a combination of genetic and neurological factors that influence speech timing and coordination (Kang et al., 2010).

Stuttering is not caused by nervousness, poor parenting, or a lack of intelligence (The Michael Palin Centre for Stammering, n.d.).
Social environments—especially those that value speed over connection—can influence how comfortable a person feels speaking (Boyle, 2013).

The most common type of stuttering (sometimes called developmental stuttering) usually develops of its own accord in childhood, most often between ages two and eight (although in rare cases it may begin much later). Roughly 4 to 5 percent of people experience stuttering at some time during their childhood. While the majority become fluent by the time they reach adulthood even without treatment, stuttering may continue to be a persistent experience for other people who stutter.

Can Stuttering Be Cured?

Despite scientific breakthroughs in our knowledge about stuttering, there is still no reliable, research-backed “cure” that works consistently, over time, and for all people who stutter.

Many individuals benefit from various forms of speech therapy and from support groups like the National Stuttering Association. Meanwhile, researchers are experimenting with electronic devices, pharmaceuticals, and other still-unproven techniques and alternative treatments.

It’s unrealistic to expect that any treatment will make stuttering completely disappear. Despite common myths, there is no therapy, device, or drug that is effective all the time or for all people who stutter. Methods that appear to benefit some individuals may not work for others, and stuttering commonly returns after periods of fluency. Managing stuttering is a long-term goal that may involve the acceptance of one’s stuttering and requires considerable patience and understanding.

What the Research Shows About Recovery

Spontaneous recovery: About 65–80% of young children who begin stuttering will naturally stop within a few years, usually within the first 2–3 years after onset (Yairi & Ambrose, 2013).
Persistent stuttering: For others, stuttering is a lifelong part of their speech pattern. Speech therapy can support communication confidence, reduce tension, and expand speaking choices, but it does not “erase” stuttering (ASHA, n.d., Boyle et al., 2013).

What Speech Therapy Can Do

Speech therapy and self-help approaches can:

Support communication ease and confidence
Reduce physical struggle or tension
Address negative feelings about speaking
Encourage self-advocacy and acceptance

Importantly, the goal of speech therapy should be about thriving while stuttering (Tichenor & Yaruss, 2019).

How Common Is Stuttering?

It has been estimated that about 1% of the adult population stutters. This would amount to almost 3 million people who stutter in the United States alone. Stuttering is about 3 or 4 times more common in males than females.

Stuttering Is Variable

The severity of stuttering varies widely among people. It may also vary in the same individual from day to day and depending on the speaking situation. Saying one’s name and speaking to authority figures may be particularly difficult. For some people, fatigue, stress, and time pressure can increase their tendency to stutter. When people who stutter feel compelled to hide their stuttering, it generally becomes more intense and/or frequent.

Patterns of stuttering behavior also vary. People who stutter may experience repetitions (D-d-d-dog), prolongations (Mmmmmmilk), or blocks (an absence of sound), or can experience some combination of these disfluency types. Some people who stutter will also try to avoid stuttering by pausing before words, substituting words, and interjecting words or phrases such as “you know,” “well actually,” “um,” etc., whenever they anticipate a moment of stuttering. As a result, the person may create the false impression of being hesitant, uncertain, or confused.

A job interview may be the single most challenging speaking situation a person who stutters will ever encounter. Stuttering is likely to be at its most frequent or intense. Therefore, the degree of stuttering at the interview should not be used to predict how the person will actually speak on the job.

What Assistance Is Available?

Although there is no simple “cure” for stuttering, people who stutter can learn to speak more comfortably, feel better about themselves and their speaking ability, and communicate more effectively.

Because stuttering typically starts between the ages of 2 and 5, early intervention is the most effective way to help children continue to speak comfortably and confidently despite stuttering, before they acquire a negative response to their stuttering. Therefore, it is important for parents and pediatricians to seek an evaluation by a qualified speech-language pathologist as soon as they become concerned about a child’s stuttering.

School-age children, adolescents, and adults can also all benefit from treatment. For these individuals, treatment is designed to help them learn to manage their stuttering so it is less disruptive to their communication. Treatment can also improve their self-esteem and their self-confidence so they can communicate more freely and effectively, which may in turn reduce the tension and frequency of stuttering moments.

Support Groups for People Who Stutter

The National Stuttering Association provides an extensive network of support groups for adults, kids, and teens who stutter, and their families across the United States. The NSA’s motto: If You Stutter, You’re Not Alone, is what our local chapters are all about! For many, NSA chapter meetings are the first time they have ever talked about stuttering with other people who stutter. Local support groups are a proven way to build self-confidence, practice speaking in a safe environment and explore new ways to cope with stuttering. People who stutter (of all ages), their family and friends, and speech-language pathologists (SLPs) are welcome at our chapters! Find the NSA Chapter nearest you.