About the presenter: Eric Jackson, MS, CCC-SLP is a New York State licensed speech-language pathologist who works with people who stutter of all ages. He is an Adjunct Professor at Long Island University - Brooklyn, teaching the graduate stuttering course and supervising graduate students in the clinic. Eric is a person who stutters and co-founder and former co-host of the StutterTalk podcast. He was Chapter Leader of the National Stuttering Association at Brooklyn College from 2008-2011 and has volunteered and presented at many self-help and professional workshops and conferences. Eric is currently a doctoral student in the speech-language-hearing sciences program at the CUNY Graduate Center.
About the presenter: Robert W. Quesal, PhD, CCC-SLP, professor in the Department of Communication Sciences and Disorders at Western Illinois University is a board-recognized specialist in fluency disorders, an ASHA Fellow. and recipient of his university's Provost's Award for Excellence in Scholarly Activity. Dr. Quesal is coauthor of OASES: The Overall Assessment of the Speaker's Experience of Stuttering, has published numerous articles and book chapters and presented workshops related to stuttering assessment and treatment.
About the presenter: J. Scott Yaruss, Ph.D., CCC-SLP, ASHA Fellow, is an associate professor in Communication Science and Disorders at the University of Pittsburgh. Yaruss teaches classes on the diagnosis and treatment of stuttering, as well as on counseling skills for speech-language pathologists. He also conducts workshops designed to help clinicians feel more comfortable with their ability to work with individuals who stutter. He is co-author of the Overall Assessment of the Speaker's Experience of Stuttering (OASES), and his research is aimed at improving the diagnosis and treatment of children and adults who stutter.

You can post Questions/comments about the following paper to the authors before October 22, 2012.

What is stuttering: Revisited

by Eric Jackson, Robert Quesal, and J. Scott Yaruss
from New York, Illinois, and Pennsylvania


Many researchers, clinicians, and people who stutter have proposed definitions of stuttering over the years (e.g., Brutten & Shoemaker, 1967; Johnson, 1959; Manning, 2010; Nicolosi, Harryman, & Kresheck, 1996; Peters & Guitar, 1991; Shapiro, 1999; Van Riper, 1982; Wingate, 1964). Many of these definitions posit the disruption in the overt speech signal (e.g. disfluency, part-word repetition, prolongation, etc.) as the central feature of the disorder. The purpose of this paper is to present a different kind of definition--one that does not neglect these overt speech characteristics as important features of the disorder, but also highlights the significance of the more difficult-to-observe aspects of stuttering. We propose that the more fundamental, and perhaps important part of stuttering -- the underlying factors that lead to overt behaviors -- must not only be part of the definition; they should be the primary focus of any definition.

The definition controversy:

The argument presented here is not exactly new. In his brilliant 1990 paper, aptly titled, "What is stuttering?" Perkins argued that listener-based definitions of stuttering must, inevitably, fail. He proposed that the "loss of control" a speaker experiences (not the acoustic interruption) is the essence of stuttering, and definitions of stuttering should reflect this distinction. His definition: "Stuttering is the involuntary disruption of a continuing attempt to produce a spoken utterance" (1990, p. 376), represented a critical shift from a listener-based definition to a speaker-based definition. However, his paper was met with significant backlash (e.g., Bloodstein, 1990; Ingham, 1990; Smith, 1990), and his definition was less-than-widely embraced. Nonetheless, Perkins's spirit runs through the heart of this paper.

Defining stuttering has proven to be a difficult task, and currently there is no universally agreed-upon definition. We are not the only field faced with the challenge of defining a complex, neurologically based disorder for which there are many factors and unknown causes. Similar problems are faced in the fields of autism spectrum disorder, attention deficit disorder, and many others. Bloodstein and Bernstein-Ratner (2008) and Yairi and Seery (2011) offered insightful commentaries regarding the difficulty of defining stuttering. In this paper, we propose that the difficulty is reflective of a surface mentality (e.g., stuttering is a speech disorder characterized by part-word repetitions, prolongations, and blocks, which can lead to. . .) Perhaps the best-known example of a "surface definition" is Wingate's (1964, p. 488):

  1. Stuttering refers to a (a) disruption in the fluency of verbal expression, which is (b) characterized by involuntary, audible or silent, repetitions or prolongations in the utterance of short speech elements, namely: sounds, syllables, and words of one syllable. The disruptions (c) usually occur frequently or are marked in character and (d) are not readily controllable.
  2. Sometimes the disruptions are (e) accompanied by accessory activities involving the speech apparatus, related or unrelated body structures, or stereotyped speech utterances. These activities give the appearance of being speech-related struggle.
  3. Also, there are not infrequently (f) indications or report of the presence of an emotional state, ranging from a general condition of "excitement" or "tension" to more specific emotions of a negative nature such as fear, embarrassment, irritation, or the like. (g) The immediate source of stuttering is some incoordination expressed in the peripheral speech mechanism; the ultimate cause is presently unknown and may be complex or compound.
In this so-called "standard" definition, the overt disruptions in speech are posited as the central features of the disorder--with all other features occurring as reactions to them. This prioritization is evident because "disruptions in the fluency of verbal expression" are reflected in part (1), and the emotional states often associated with stuttering are described as "accompanying" those disruptions. Van Riper warned of this "observational" kind of definition more than forty years ago (1971, p. 14). Yet, many definitions referenced today appear to be some kind of variation of Wingate's definition.

Why surface definitions fail:

Research has repeatedly demonstrated that the fluent speech of people who stutter and people who do not stutter differs significantly in acoustic (e.g., Bloodstein, 1944; Starkweather & Myers, 1979; Healey, 1982; Hall & Yairi, 1992; Max & Gracco, 2005), myographic (e.g., Guitar, Guitar, Nelson, O'Dwyer, & Andrews, 1988; van Lieshout, Peters, Starkweather, & Hulstijn, 1993), and kinematic (e.g., Zimmermann, 1980a, 1980b; van Leishout, Hulstijn, & Peters, 1996; Kleinow & Smith, 2000; Max, Caruso, & Gracco, 2003) measures. Furthermore, neuroimaging data over the last fifteen years suggests that the brains of people who do and do not stutter are significantly different in both structure and function (e.g., Chang et al., 2008; Sommer et al., 2002; Watkins et al., 2008; Cykowski, 2010). Because most of the above-mentioned data have been obtained from more experienced (i.e., older) stutterers, it is difficult to determine whether these differences are reflective of or a reaction to stuttering. In either case, however, the differences represent a deviation from typical functioning. This deviation likely manifests in struggle or additional effort required for communication. Further, an increasing evidence base has demonstrated similar physiological differences in younger speakers closer to the onset of stuttering (e.g., Smith, Goffman, Sasisekaran, & Weber-Fox, in press).

Smith (1999) uses the appropriate analogy of a volcano in discussing this issue. She describes how examining surface features to understand stuttering is like studying smoke emitted from volcanoes to understand volcanic activity. She also explains how the field of volcanology did not progress until there was a shared understanding amongst volcanologists that seismic activity is what drives volcanic behavior. As such, Smith argues that stuttering can occur in the absence of observable features. This assertion serves as a cornerstone for the arguments presented in this paper.

Additionally, people who stutter develop the remarkable ability to anticipate when certain sounds or words will be overtly stuttered. This means that the stutterer in many cases has the ability to "abort" the speech process before stuttering gets to the surface (i.e., becomes noticeable). Consider the following scenario:

A man who stutters orders take-out. When he called to place the order, the restaurant asked for his first and last name. When he entered the restaurant to pick up his order, the cashier only asked for his name, giving him the option of saying his first OR last name. His intention was to say his first name followed by his last name. Before he responded, he was sure that he would have difficulty with his first name; typically, his last name is easier to say. Thus, at that moment and in that particular situation, he had two options (and presumably others) to utter his name "fluently": 1) hesitate (even only for a fraction of a second), wait for the stuttering to "pass" and say his first name; or 2) say his last name only. With both options, the speaker will appear fluent and "normal" to the listener. However, both require significantly more effort (e.g., cognitively, emotionally) than if stuttering would not have occurred. A definition that prioritizes the overt behaviors associated with stuttering over the underlying features is misrepresentative because those overt behaviors are not always associated with stuttering, especially with more experienced stutterers; the lack of integration of the underlying processes (whether neurological, speech-motor, linguistic, emotional, or a combination thereof) required for effortless speech, however, is.

Limitations of a surface definition:

Surface definitions leave researchers, clinicians, and listeners susceptible to viewing stuttering, and the person who stutters, narrowly. Narrow definitions have important clinical and research consequences. First, a focus on observable behaviors of speech may lead to compromised judgments and measures of stuttering. For example, many stutterers become skilled at circumventing overt stuttering by switching words, pausing/hesitating, initiating accompanying body movement, using fillers/starters, circumlocuting (i.e., talking around the point), or by not talking at all. We propose that when these "tricks" are employed, stuttering is in fact occurring, albeit under the surface. Thus, a measurement based on the overt characteristics of speech might not reflect many instances of stuttering. Silverman stated that, ". . .when a stutterer doesn't speak, he or she doesn't stutter!" (2004, p. 12). We refute this assertion. It would be more accurate to say that when a stutterer stutters, he or she may choose not to speak.

Second, a surface definition de-emphasizes the experience of the individual, in some cases, by not mentioning it at all. As many have argued, the most severe stuttering problems can occur in those who rarely demonstrate overt stuttering behaviors (e.g., Van Riper, 1982; Cooper, 1993; Murphy, Quesal, & Gulker, 2007; Sheehan, 1970). Many individuals are faced with the constant burden of trying not to stutter. Additionally, these individuals may be making life choices at least partly based on stuttering or the possibility of stuttering (Manning, 2010). An examination of disfluency, which can be viewed as the end result in the stuttering chain, cannot fully reflect the impact that stuttering might have on an individual's life (Yaruss & Quesal, 2004).

Third, a symptom-based definition can lead to narrow treatment approaches focusing only on behavioral aspects of stuttering (Yaruss, 2007). These "end results" of stuttering are important, especially since most accepted therapy approaches (e.g., stuttering modification, "normal talking," fluency shaping) include large behavioral components. However, they cannot be the only focus in therapy with all individuals who stutter. For example, many older PWS experience anxiety, fear, and embarrassment as a result of communication difficulty. Making meaningful changes to behavioral components of speaking could be challenging for these individuals if emotional and cognitive features are not concurrently addressed. For further discussion regarding the limitations of narrow treatment approaches, as well as the importance of comprehensive treatment approaches with school-age children, see Yaruss, Coleman, and Quesal (in press).

Fourth, a definition that prioritizes overt features contributes to the public misunderstanding of the disorder. The uneducated public holds the view that stu-stu-stuttering is when a person repeats sounds or syllables (like puh-puh-Porky Pig). While stuttering is ongoing when these behaviors are present, it can also be ongoing when the behaviors are not present. What the layman does not know about stuttering is that much of the speaker's time is spent trying not to overtly stutter--often unsuccessfully so. This misunderstanding is evident if one performs a Google search on "stuttering." In doing so, the top non-sponsored link is the National Institutes of Health (NIH) definition: "Stuttering is a speech disorder in which sounds, syllables, or words are repeated or last longer than normal. These problems cause a break in the flow of speech (called disfluency)." The third non-sponsored link is the American Speech-Language-Hearing Association definition: "Stuttering affects the fluency of speech. It begins during childhood and, in some cases, lasts throughout life. The disorder is characterized by disruptions in the production of speech sounds, also called 'disfluencies'." The Diagnostic and Statistical Manual of Mental Disorders -- 4th Edition (DSM-IV, 1994) also offers a definition, in which stuttering is a, ". . .disturbance in the normal fluency and time patterning of speech that is inappropriate for the individual's age. This disturbance is characterized by frequent repetitions or prolongations of sounds or syllables. . ." All of these definitions prioritize the observable speech characteristics by putting them first in the definition. To illustrate this point further, it is helpful to look at other complex, neurological disorders. Parkinson's disease (PD), for example, is typically defined as a progressive, neurological disorder associated with a death of dopamine cells in the basal ganglia. Symptoms of PD include tremors and effortful speech. However, you would be hard-pressed to find PD defined primarily as a ". . .disorder characterized by shaky hands."

Finally, most surface definitions use the term fluency (or disfluency) to characterize stuttering. This term can be misleading. Most experts define fluency as the continuous flow of speech. The term by itself (how it is often used by people who stutter, professionals, and students), however, may not account for instances in which the speaker demonstrates intention to speak, but chooses not to do so due to impending overt disruption. Many definitions include avoidance as a feature accompanying disfluency; however, this de-emphasizes the role that awareness (and thus avoidance) plays on shaping fluency. Additionally, identifying moments of disfluency has been problematic, and research has demonstrated a lack of reliability between investigators in counting these moments (e.g., Curlee, 1981; Kully & Boberg, 1988; Cordes, Ingham, Frank, & Ingham, 1997). Lastly, Smith (1999) has demonstrated that it is virtually impossible to accurately determine when stuttering begins and ends, providing additional evidence that a definition based on surface features (which necessitates a beginning and end) is flawed.

An updated definition:

The proposed definition below is an attempt to augment Perkins' 1990 definition and reflect the more than twenty years of research on stuttering since. Instead of positing the speech behaviors as the central features of stuttering, we are proposing that the underlying mechanisms that lead to those behaviors should be recognized as the core of stuttering.

Stuttering is a neurobiological lack of integration of the underlying processes of planning and producing language and speech that, upon verbal execution, can lead to interruptions in the acoustic speech signal (e.g., blocks, part-word repetitions, disfluencies) and physical struggle (e.g., tension). These surface behaviors may not be present, however, when the speaker exhibits communicative avoidance (e.g., circumlocutions, fillers). The underlying features may lead to surface behaviors, as well as emotional and cognitive reactions. Depending on the individual, these may result in significant difficulties in communication and an adverse impact on the speaker's quality of life. The physical symptoms, emotional and cognitive reactions, and impact on the speaker's life all comprise the disorder of stuttering. Most existing definitions imply that the interruption in the speech signal is the primary (or central) feature of stuttering--with all other features occurring as reactions to it. In contrast, the above definition postulates that the "lack of integration of the underlying processes" (like Perkins's loss of control) is the core feature of stuttering. The definition does not necessarily imply a sequence of events; rather, it attempts to reflect the importance of certain features. Though brain imaging techniques have drastically improved since Perkins' definition, the underlying processes and how they integrate to produce typical and stuttered speech are currently not well understood. Hopefully, as technology and research methodology advance, we will gain a better understanding regarding those underlying mechanisms. Additionally, the above definition does not explicate cause--a task more suited for a model or theory of stuttering. It is implied that there is a strong genetic component to stuttering, and that a combination of factors (e.g., linguistic, temperament) likely contribute to its onset and development.

In order for stuttering to occur, there needs to be communicative intent. The above definition proposes that stuttering begins in the early stages of speech and language planning and production (e.g., the conceptual and encoding stages of Levelt, 2000) and only becomes noticeable depending on the degree to which the speaker attempts to execute his or her speech plan (i.e., talk). Importantly, it is probable that surface behaviors and communicative avoidance often occur concurrently and simultaneously. Additionally, the presence of awareness is an important aspect of stuttering because it can significantly shape behavior (e.g., how a person stutters). It is likely that all individuals who stutter possess at least some awareness (e.g., mental, proprioceptive) of communication difficulty, and while older speakers demonstrate a more developed awareness, even the youngest of speakers have demonstrated this characteristic (e.g., Langevin, Packman, & Onslow, 2009; Vanryckeghem, Brutten, & Hernandez, 2005; Yairi & Ambrose, 2005).

In this short paper, we have discussed the difficulties and some of the controversy surrounding the defining of stuttering. While our definition is merely an initial attempt at capturing, in few words, the essence of stuttering, we hope that we have appropriately highlighted the limitations associated with "surface" definitions, as well as the importance of opening this conversation again.


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You can post Questions/comments about the above paper to the authors before October 22, 2012.

SUBMITTED: August 14, 2012
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