Written by: Dain Hong / Stuttering / December 2019

Stuttering, refers to speech characterized by an abnormally high frequency of stoppages. Such stoppages in the flow of speech — or disfluencies—may come in the form of involuntary repetitions of sounds, syllables (beats), words, sound elongations, blocks or pauses. 

There are typical disfluencies that any speaker may experience. These are typically word repetitions and pauses, as seen in the following example: “Could you… uh could you pass me the pen next to you?” The sentence includes a phrase repetition (could you), filler (uh), and a pause. These disfluencies can occur when the speaker is hesitant about the message, is distracted away from the message –possibly due to tiredness or an object demanding their attention, is overly conscious about the message formation, or due to no reason at all. 

While everyone may experience such disfluencies from time to time, it is not a consistent barrier to their speech. For People Who Stutter (PWS), however, disfluencies occur on a more regular basis, despite knowing exactly what they want to express. There are generally two kinds of such stuttering— developmental and neurogenic stuttering. The former type describes stuttering that begins in childhood, and the latter describes one that occurs after brain injury. Some characteristics of stuttering include high frequency and/or duration of stoppages, as well as certain varieties such as sound and syllable repetitions, sound elongations and blocks. An example of a sentence could be the following: “C-could you pass mmmme the p-pen next to you?” 

Another aspect of developmental and neurogenic stuttering is secondary behaviors. Used as a coping mechanism, such behaviors include escape and avoidance, which require constant monitoring and intentional selection of vocabulary based on preferred sounds. If a speaker has difficulty with b-initial and p-initial words, instead of saying “I bought a pair of pants”, they may say “I got myself some trousers”. Secondary behaviors can also refer to involuntary facial movements, such as eye blinks and jaw twitches. These typically happen due to an anticipation of the feared sound and the tension that builds up as a result.

Although the root of stuttering is still a mystery, research has shown the influence of both nature and nurture. There is greater likelihood for an individual to stutter if they have a family member who stutters. While genes may play a part, there is no guarantee that a parent who stutters will have a child or a grandchild who also stutters. Moreover, fast-paced environments, increased exposure to fast-speakers, and having to fight for speaking time have shown to be potential factors in stuttering. At the same time, some children thrive in these busy contexts, and develop important communication skills through them. Overall, while there have been numerous common threads among PWS, there is not a single common denominator that allows us to identify the main cause of stuttering. 

This question is slightly different from the previous in that it looks at the speech science behind stuttering. Seeing that stuttering occurs despite the speaker’s confidence in the content of the message, we can accept that it is due to an incoordination between breathing and speaking. As our breath forms the foundation of speech, a stutter is an interruption of that flow due to tension in parts of the vocal passage. There could be tension in the glottis or vocal cords, leading to blocks, and tension in the tongue or lips, leading to sound, syllable and word repetitions. Tension acts against the brain in its control over muscle movements and thus results in productions that were not intended. 

The most common sounds that are stuttered on are explosive sounds like initial p/t/k and b/d/g, as well as initial vowels. The former involves a buildup of air pressure that becomes almost uncontrollable with added tension, and the latter involves “turning the voice on” at the level of the vocal folds that may become abrupt with added tension. 

Since the foundation of speech is airflow and disfluency results through disrupted airflow, fluency is achieved by increasing airflow. This involves reducing tension in various areas of the vocal tract, using gentle contact between speech muscles, and keeping the voice “on” through sing-songy attributes. These technical tools are accompanied by environmental modifications to increase fluency-inducing conditions, in addition to discussions about one’s perceptions of stuttering so that there could be movement towards acceptance of stuttering. 

To speak with one of the speech-language pathologists at Well Said: Toronto Speech Therapy, schedule an initial consultation by clicking the link below or calling (647) 795-5277.