Stuttering –What is it?

Stuttering, (also known as stammering) is a disorder involving the production of free flowing speech.  While the term has commonly been associated with involuntary  syllable repetition, it also includes the word and phrase repetition, prolongation of sounds and the abnormal hesitation or pausing before and/or during speech in which the individual is unable to produce words or sounds to varying degrees, referred to as speech blocking.

The ISA wishes to highlight that a complete understanding of stuttering needs to incorporate more than the listeners perspective but also account for the speakers experience. Consequently the ISA board promotes the terms Stuttered Speech Syndrome (negative feelings, attitude and behaviour) and covert stuttering (word avoidance, substitution and circumlocution) to clarify discussions about stuttering and its effects.


The cause of stuttering is unknown althought a hereditary factor has been identified as it itends to run in families.

Stuttering is generally not a problem with the physical production of speech sounds or putting thoughts into words. Despite popular perceptions to the contrary, stuttering does not affect and has no bearing on intelligence. Apart from their speech impairment, people who stutter are generally normal in every other way. Anxiety, low self-confidence, nervousness, and stress therefore do not cause stuttering, although they are very often the result of living with a highly stigmatized disability.

Variable Effects

It is clear that this disorder affects different people in different ways. Some experience it as frequent word repetitions or prolongations especially during periods of heightened anxiety and describe it in terms of being just a minor inconvenience in the free flow of speech. Others experience it as a complete blockage or cessation of the ability to speech. Speech block stuttering is generally accompanied by habitual struggle behaviour associated with efforts to release the speech block. Individuals afflicted in this way can experience the disorder as a major disability in not only their efforts to speak to other individuals but also as something that can affect their whole experience of life itself.

While stuttering is said to affect about 1% of the population some individuals are able to hide their speech blocks through word and situation avoidance and circumlocution. This form of stuttering has been referred to as “covert stuttering” due to its deliberately hidden nature. The covert stutterer’s greatest fear is how others may judge them if they happen to lose control while speaking and experience a speech block. Many are reluctant to admit to anyone that they have any stuttering behaviour.

The emotional reaction of any individual to the stuttering often constitutes the most significant aspect of the disorder. It is important that family, friends, relatives, work colleagues and the public in general understand that much of what constitutes stuttering and more particularly “speech blocking” goes much deeper than the dysfluent speech that the listener hears. This includes such things as sound and word fears, situational fears, fears associated with negative judgment by others. Stuttering can lead to what some are calling “Stuttered Speech Syndrome”. Symptoms of this include increased dysfluency, a feeling of loss of control of speech, associated high anxiety or panic, depression, low self-esteem, social phobia and confusion over issues of personal identity.

Variable Severity

The severity of stuttering can vary greatly for any particular individual and can be specific to certain words and situations e.g. talking on the telephone, ordering in a restaurant, speaking to an authority figure. Many individuals have a problem in saying their name when they have to introduce themselves. There are a small percentage of people who have severe blocking on almost every word, in almost every situation. These people are generally less anxious about their stuttering than those who block infrequently as the latter group are uncertain when stuttering might appear. This phenomenon highlights the need to regard the severity of stuttering as independent of the severity of Stuttered Speech Syndrome. A person with apparent infrequent stuttering may be severely affected by Stuttered Speech Syndrome while the converse can also apply.


There are many treatments, devices and speech therapy techniques available that, to varying degrees, can help some people who stutter to control or reduce both the problem of dysfluency itself (stuttering) and of negative reactions to it (Stuttered Speech Syndrome). The ISA highlights the value of self-help and support groups in this process.


Version 1

The above is a  NON OFFICIAL issue of the “Public Awareness Message”. This issue was approved by ISA board  for wider consideration by ISA member associations.

It was discussed  at the ISA membership meeting in Croatia on May 6, 2007.