Information About the IFA

1. Types of fluency disorders

Many people think of stuttering1 when they hear the term “fluency disorder.”

However, this term covers a wider range of conditions that impact the ability to produce fluent speech:

  • childhood-onset fluency disorder
  • non-organic stuttering
  • neurogenic stuttering
  • cluttering

The type of stuttering that people typically know about is classified as “childhood-onset fluency disorder.” The conditions “neurogenic stuttering” and “non-organic stuttering” emerge primarily in adulthood. The final condition, “cluttering” can occur from early childhood and in many cases is found to co-occur with stuttering.

2. What is childhood-onset fluency disorder (stuttering)?

Stuttering can be found all over the world, across different cultures and races. It has no connection to occupation, academic background, or other demographic variables (Guitar, 2014). Although the exact cause is unknown, there is abundant evidence that genetic and neurodevelopmental factors are involved in the onset and persistence of stuttering (cf Kraft & Yairi, 2012 and Chang & Zhu, 2013). There have also been numerous reports on the effectiveness of different therapies, especially with children (Bloodstein & Bernstein Ratner, 2008). In the Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) (American Psychiatric Association, 2013), the following characteristics have been associated with stuttering:

A. Disturbances in the normal fluency and time patterning of speech that are inappropriate for the individual’s age and language skills, persist over time and are characterized by frequent and marked occurrences of one (or more) of the following:

1. Sound and syllable repetitions. 2. Sound prolongations of consonants as well as vowels. 3. Broken words (e.g., pause within word). 4. Audible or silent blocking (filled or unfilled pauses in speech). 5. Circumlocutions (word substitutions to avoid problematic words). 6. Words produced with an excess of physical tension. 7. Monosyllabic whole-word repetitions (e.g., “I-I-I-I see him”).

B. The disturbance causes anxiety about speaking and documented limitations in effective communication, social participation, and academic or occupational performance, individually or in any combination (see, for example, Craig & Tran, 2014; Craig, Blumgart & Tran, 2009; Yaruss, 1998; McAllister, Collier, & Shepstone, 2012) Some vocational limitations may be self-imposed by those seeking occupations not requiring extensive speaking. However, the frequency of speech behaviors and resulting anxiety or functional impairment are not well-correlated in many cases (Manning & Beck, 2013), which means that a low frequency of stuttering may handicap less, more or equally as a higher rate of stuttering. This may suggest the need, in fluency assessment, to gather information about the impacts of stuttering on other aspects of the individual’s thoughts, emotions, social, educational and/or vocational function.

C. The onset of symptoms is in the early developmental period, following previously fluent speech production by the child. (Note: This is why childhood stuttering was moved recently away from its historical code of 307.0 in the DSM and International Classification of Diseases (ICD) to the sequence 315.35. Later-onset cases not attributable to neurological insult or secondary to other medical conditions are diagnosed with the older code 307.0[F98.5] adult-onset fluency disorder: American Speech-Language-Hearing Association, 2010) Older adolescents or adults who have been stuttering for many years may have an entrenched pattern which may consist of blocks, repetitions, and prolongations, accompanied by tension, struggle, as well as escape and avoidance behaviors. They may have developed negative anticipations about speaking situations and listener reactions. The complex patterns of advanced stuttering involve behaviors, emotions, and cognitions.

3. To people who would like to know more about stuttering

A. Types of stuttering

Although people might simply refer to it as “stuttering”, the term covers many different types of interruptions in speech. The following three types are most common: ・ the sound is repeated (e.g., “m,m,m, myself”). ・ the sound is prolonged (e.g., “mmmmmmmmyself”). ・ the speaker appears frozen in an articulatory posture and can’t move forward (e.g., “......... myself”). We call this a block.

People who stutter may also show other behaviors, which mostly result from trying to overcome stuttering. For example, people who stutter may move their bodies, such as shaking their head, constantly blinking their eyes, or stamping their feet while talking. Sometimes the effort to overcome a stutter may become so strong that there is observable physical tension, for example, around the mouth or throat.

B. Individual differences in stuttering behaviors

People do not always stutter in the same way; even for a single speaker, there are times when the stuttering is either more or less pronounced (Karimi, et al. 2013). The way that stuttering occurs also differs from person to person. There are a variety of factors that can bring about changes to stuttering patterns (see review in Bloodstein & Bernstein Ratner, 2008): ・your physical condition (e.g. feeling tired) ・your emotional condition (e.g. feeling anxious, excited) ・the environment where you have to talk (e.g. school, home) ・the words being used (some people develop particular concerns about certain words or sounds, including their own name) ・the person you are speaking to The environment is likely to have the biggest impact on your speech for the following reasons: ・You might have been teased and had unkind things said to you by your friends which might affect your confidence in speaking; we know that people who stutter are frequently bullied (e.g., Blood et al., 2011) ・You might be worried about whether you can read materials out loud or give presentations in class ・You might be afraid to raise your hand in class, even though you know the answer, but you cannot say it ・You might become frustrated because you cannot easily express what you want to say ・You might really want to talk, but give up because it is too difficult. There might be times when you feel down because of not being able to say what you want to. It is important to be able to talk to someone about these feelings.

C. ‘It’s okay to stutter’

It is important to remember stuttering is not a bad thing nor does it define you as a person. Unfortunately, some people you will meet might not have a good understanding of stuttering, which is why we should all work together to try to change the world one step at a time.

4. Where to go for consultation and support if you stutter?

A. Speech and language pathologist/therapist.

A speech and language pathologist (also known as a speech and language therapist or logopedist) is a professional who provides guidance and support to people with speech and language difficulties. Education about stuttering is included as part of the training process for speech and language pathologists, but it is not necessarily the case that all of them have the same skills or experience working with people who stutter. In many regions, specialty recognition for therapists with specific expertise in working with fluency disorders is increasingly common (e.g., the American Board of Fluency and Fluency Disorders (, or The European Clinical Specialization on Fluency Disorders ( ). Speech and language pathologists work primarily in educational institutions, clinics or hospitals, although many of them have private practices. It is recommended that when seeking guidance and/or support, people should ask about their specialism and experience in the area of stuttering before making an appointment.

B. Self-help groups

In some areas, self-help groups have been established to allow people who are affected by stuttering to meet on a regular basis. At these gatherings, people talk to each other about the problems caused by stuttering and discuss how to handle stuttering-related issues.

Self-help groups do not provide scientific expertise on stuttering or specialized guidance or support to help improve stuttering, as a speech and language pathologist would. However, there are a number of benefits that can be obtained by going to a self-help group. Being part of such a group can provide a sense of solidarity, because people share their worries about stuttering and get concrete advice from people who have the same concerns. Self-help group attendance has been associated with increased self-efficacy among people who stutter (Boyle, 2015).

The International Stuttering Association (ISA) is an international self-help group. It was founded in 1995 as a non-profit organization that connects various self-help groups around the world. Since then, the ISA has taken a variety of actions to allow the voices of people who stutter to be heard across the world. Similar, nationally-based self-help groups for both adults and children who stutter can be found in many regions; see representative links to such groups at the ISA:

It is likely that there are self-help group initiatives in your town or city, and many of these self-help groups have regular meetings. In addition, there are other groups that implement specific projects such as issuing reports to inform the general public, organize lectures with specialists in the area of stuttering, or running workshops.

5. To the parents, guardians and the teachers of children who stutter

Please do not worry about a child’s stuttering on your own. By consulting with specialists and exchanging information with other parents and caregivers who have the same worries, you will find support and useful tips to handle daily situations involving the child who stutters. Some parents or guardians of children who stutter worry that they have somehow caused their child’s stuttering. However, there is no evidence to suggest that children start to stutter because of their upbringing; experience; parental behaviors with children who stutter have long been known to be similar to those who do not stutter (e.g., Miles & Bernstein Ratner, 2001) The research evidence indicates that stuttering develops because of a combination of genetic and neurodevelopmental factors, which may result in the child’s speech motor and linguistic skills being outstripped when he tries to express himself. It is sometimes helpful for people in the child’s environment to help him by providing the time and space to speak without pressure. In many cases, stuttering gradually improves. In more than half the cases of early stuttering, it will resolve in the pre-school years without any special type of guidance or support (cf, Yairi & Ambrose, 2005; Reilly et al., 2013). This is known as spontaneous recovery. For those children whose stuttering does not appear to be resolving, there are many effective therapy programmes for pre-school children. For school-aged children who stutter, support from a specialized speech and language pathologist can be sought to help children find ways to manage their stuttering more easily. In this way, children are able to live their everyday lives and their stuttering has much less impact on them. It is important to remember that people who are part of the child’s life have a key role to play in reinforcing the message that it is okay to stutter.

1  Stuttering and stammering mean the same and can be used interchangeably. The term stuttering will be used in this document.



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