Types of Stuttering: Causes, Features and Treatment

01Origins

Types of stuttering by cause

• Developmental stuttering: the most common type. It starts in early childhood, often between two and five years, when language skills are expanding quickly. Genetics play a large role, and it is more common in boys.
• Neurogenic stuttering: appears after a stroke, head injury, brain tumour or neurological disease such as Parkinson’s. Disfluencies may occur on any part of a word and are often less influenced by anxiety.
• Psychogenic stuttering: rare; it starts suddenly in adulthood after significant emotional trauma or stress, sometimes alongside other symptoms. It requires careful assessment.

Some sources also describe cluttering, a separate fluency disorder with rapid, irregular speech that can coexist with stuttering.

02Disfluencies

Types of disfluency

• Repetitions: repeating sounds («b-b-b-ball»), syllables («ba-ba-baby») or whole short words («I-I-I want»).
• Prolongations: stretching a sound («sssssun»).
• Blocks: the mouth is positioned to say a word but no sound comes out for a moment, often with visible tension.
• Interjections: extra sounds or words such as «um» or «like», sometimes used to get past a block.

Everyone has some normal disfluencies, such as revising sentences or saying «um». Stuttering-like disfluencies are more frequent, involve tension and affect communication.

03Secondary

Secondary behaviours and feelings

• Eye blinking, head jerks, facial tension or tapping during stuttering moments.
• Avoiding certain words, switching words or pretending not to know the answer.
• Avoiding speaking situations such as phone calls or introductions.
• Anxiety, embarrassment or frustration about speaking.

These behaviours often develop as ways to cope with stuttering and are an important part of therapy.

04Children

Stuttering in young children

Many young children go through a phase of normal disfluency between two and five years. Stuttering is more likely to persist if it has lasted more than six months to a year, there is a family history of persistent stuttering, it started after age three and a half, the child is a boy, or there are other speech and language difficulties. Parents can help by slowing their own speech, giving time, listening to what the child says rather than how, and avoiding telling the child to «slow down» or «start again». Early assessment is recommended if parents are concerned.

05Assessment

How stuttering is assessed

A speech and language therapist listens to speech in different situations, counts and describes the types of disfluency, notes secondary behaviours and asks about feelings and the impact on daily life. For adults with sudden onset, medical assessment helps identify neurogenic or psychogenic causes.

06Treatment

Treatment approaches

• Young children: parent-delivered programmes such as indirect approaches that change the communication environment, or direct programmes where parents give feedback on smooth speech under therapist guidance.
• School-age children: fluency techniques, desensitisation and building confidence.
• Fluency shaping: learning a slower, smoother speech pattern with gentle onsets and easy breathing.
• Stuttering modification: learning to stutter more easily, with less tension and avoidance.
• Cognitive and acceptance-based approaches: reducing anxiety and avoidance around speaking.
• Support groups for people who stutter and their families.

See how to stop stuttering for practical strategies.

07Myths

Common myths

• Stuttering is not caused by nervousness or poor parenting, although stress can make it worse.
• People who stutter are not less intelligent.
• Telling someone to slow down or relax does not help.
• Finishing someone’s words is usually not helpful; patient listening is.

09Listeners

How to talk with someone who stutters

• Keep natural eye contact and wait patiently.
• Do not finish words or sentences unless asked.
• Avoid advice such as «slow down» or «take a breath».
• Respond to what is said, not how it is said.
• Give extra time on the phone and in meetings.
• Ask the person what helps them, as preferences differ.

A supportive listener reduces pressure and makes communication easier for everyone. Teachers can agree with a pupil who stutters how and when they prefer to answer questions or read aloud in class.

10Summary

Key points to remember

• Developmental stuttering is the most common type and begins in childhood.
• Neurogenic and psychogenic stuttering start later and have different causes.
• Repetitions, prolongations and blocks are the core disfluencies.
• Speech and language therapy helps at every age.