The fluency area is plagued with inconsistent, confusing terminology. This problem has cultural, historical, linguistic, and practical origins. The following examples illustrate some of these influences. In most cultures, stuttering is one of the most well-known speech disorders and is labeled in some form in all languages. In some languages, the label is a relatively neutral, descriptive term that refers to both normal and abnormal behavior. In English, for example, stuttering can refer to normal stumbling over words or to the abnormal speech disorder. This leaves English speakers confused about the best meaning of the term and contributes to one of the most difficult issues in definition, notably that most normal speaking adults report that they have “stuttered” occasionally but emphatically do not regard themselves as “stutterers.” (The issue of using the direct label, stutterer, versus the person-first label, person who stutters, is discussed in section 3.5.5.) Yet, even when it is clear that abnormal speech is implied, stuttering may also refer to a general style of speech (i.e., “That person stutters”) or to specific speech events (i.e., “His primary stuttering symptom is part-word repetitions”). In other languages, such as Arabic, the terms for stuttering carry serious negative connotations and refer not only to a speech disorder but to other problems, such as mental incapacity. Furthermore, society often forms perceptions of individuals who stutter that differ from the self-perceptions of the stutterers themselves. Added to these problems is the fact that the literature on speech and language disorders contains terminology introduced in early classifications but rarely used today (e.g., a semantic distinction between stuttering and stammering).
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The problem of terminology has been most acute in the area of research, in which defensible, reliable, and agreed-on definitions are critical to carrying out investigations that are comparable to other studies. Clinicians, too, need to know what constitutes stuttering and other fluency disorders in order to plan treatment and to communicate effectively with their clients and other clinicians. Additionally, the demands of health care systems require that providers strive for consistency and clarity of terminology, especially in reporting assessment and outcome measures. For these reasons, the terms highlighted in these Guidelines are defined with the intention that more consistent usage and, thereby, more precise communication by researchers, clinicians, and others will eventually result. Whenever possible, the Task Force sought to recommend terminology and definitions currently being utilized by well-known professionals. Clinicians, health care professionals, and researchers are encouraged to use the terms in bold type whenever possible. In some cases, the definitions listed can be used accurately in most contexts. In other cases, however, users are cautioned to keep the purposes of their definitions in mind. For example, there are four different definitions of the term stuttering, each representing important aspects of the problem and unique perspectives on definition. It would be a serious mistake for a user to select any one of the stuttering definitions and assume that it would apply equally well for teaching, clinical, research, consumer affairs, and third-party reimbursement purposes. For each term, the definitions the Task Force considered to be the preferred usage are in bold type. These are followed by relevant explanations or brief discussions and, in some cases, synonymous—or nearly synonymous—terms.
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Traditionally, fluency has been defined in the area of speech-language pathology by what it is not, namely speech that does not contain perceptible deviations in smoothness or flow of speech. Also, in a more restricted clinical sense, fluency is used as the converse of stuttering to identify speech sequences that are free of stuttering, as in the statement, “Stuttering was followed by instructions to repeat, and fluency was reinforced verbally.” And in recent years, fluency has been used increasingly to refer specifically to stuttering (e.g., “a fluency client”). The Task Force recommends that the professional community not use the term fluency to refer to stuttering. For example, it would be more precise to say or write: a diagnosis of “stuttering” rather than a diagnosis of “fluency,” “client with stuttering” instead of “fluency client,” and “stuttering treatment” instead of “fluency treatment.” Those terms, however, may be appropriate in other contexts that do not include or relate to stuttering per se.
Fluency is used in the area of neurogenic communication disorders (i.e., aphasia) to refer to the perceived natural continuity and rate of spontaneous speech, even though there may be a substantial number of language errors (e.g., a “fluent aphasic” as opposed to a “nonfluent aphasic”).
In the area of foreign language learning, fluency may refer to the general competence or facility with which a speaker can communicate orally in the new language(s) (e.g., “fluent in French”). In this usage, fluency is roughly equivalent to “overall spoken language proficiency.” In addition to this general usage, fluency also refers more specifically to the rate, continuity, rhythm, and effort with which the language is produced (e.g., “The speaker's knowledge of Russian vocabulary is adequate, but his fluency in spoken Russian is weak”). As noted by Wingate (1984), fluency typically refers to spoken language, but, presumably, it would be appropriate to refer to one's fluency in American Sign Language.
The Task Force proposes that the scientific community consider the value of the concepts of “motor fluency” (e.g., speech coordination variables related to fluency in a stutterer) versus “linguistic fluency” (e.g., lexical, syntactic, or semantic variables related to fluency in a foreign language speaker or a clutterer). Research is ongoing in these areas and may suggest other or better ways to account for the often conflicting, contradictory uses of the term fluency. In any case, appropriate descriptors or clarifiers should be used to minimize confusion regarding the use of the term.
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In recent years, the profession of speech-language pathology has adopted the term fluency disorders to denote a category of “speech disorders” (as opposed to “language disorders”), that includes such related disorders as stuttering and cluttering as well as the more specific categories of neurogenic stuttering and psychogenic stuttering. Indeed, the Special Interest Division responsible for these Guidelines deals with “fluency and fluency disorders.” Specific disorders of rate (i.e., too fast, too slow, or too irregular) are generally considered to be fluency disorders as well, even though other disorders (e.g., word retrieval or insufficient vocabulary) might be present and even responsible for rate problems.
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The generic term disfluency refers to breaks that are normal, abnormal, or ambiguous (i.e., sometimes regarded as normal and sometimes abnormal). The most commonly regarded normal disfluencies are: hesitations or long pauses for language formulation (e.g., “This is our [pause] miscellaneous group”); word fillers (e.g., “The color is like red”), also known as “filled pauses”; nonword fillers (sometimes called interjections, e.g., “The color is uh red”); and phrase repetitions (e.g., “This is a—this is a problem”). The most common ambiguous disfluencies are whole word repetitions (e.g., “I-I-I want to go” or “This is a better-better solution”). The most commonly regarded abnormal disfluencies (i.e., stutterings) are: part-word (or sound/syllable) repetitions (e.g., “Look at the buh-buh-ba-baby”); prolongations (e.g., “Ssssssssometimes we stay home”); blockages (silent fixations/prolongations of articulatory postures) or noticeable and unusually long (tense/silent) pauses at unusual locations to postpone or avoid (e.g., “Give me a glass (3-sec pause) of water”); and any of the above categories when accompanied by decidedly greater than average duration, effort, tension, or struggle.
Although the term disfluency does not necessarily imply abnormality, it is often used synonymously with stuttering and, as noted in section 3.4, interchangeably with dysfluency. Clinicians often use disfluency to refer to stuttering for a number of reasons, including: (a) assuming it is perceived by clients to be, connotatively, a less negative term than stuttering, (b) believing it sounds more scientific or objective than stuttering, or (c) regarding it to be synonymous with stuttering. There is little empirical or logical support for any of these assumptions. Clinical researchers occasionally prefer the term disfluency to stuttering because they find it easier to make reliable judgments of all disfluencies than only those further judged to be stutterings.
“Normal developmental disfluencies” refer to higher than adult levels of normal disfluencies that occur in preschool children as they learn language normally. Approximately half of nonstuttering children go through an identifiable period of “increased normal developmental disfluency” during this time (Johnson & Associates, 1959).
Starkweather (1987) introduced the term discontinuity because it differentially refers to breaks in the continuity or flow of speech and not to other problems of fluency, such as a rate that is too slow. Given Starkweather's analysis, the Task Force concurs that the term discontinuity makes a useful distinction and, therefore, might result in more incisive use of terminology. Nevertheless, it chose to accord preference to the term disfluency (in spite of its misuses) because it is overwhelmingly the more popular term referring to breaks in continuity.
Nonfluency is sometimes used synonymously with disfluency.
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According to Wingate (1984), the “dys” and “dis” prefixes are quite different. The “dys” prefix implies abnormality, such that a word beginning with “dys” denotes an abnormal condition. By contrast, the “dis” prefix denotes separation, negation, or signals a contrast with the morpheme that follows it. Wingate cites three of four dictionary references to support his view. It must be pointed out, however, that all dictionaries, such as the Oxford Unabridged Dictionary, do not show this distinction. Some hold that the “dys” prefix in the field of speech-language pathology implies an underlying, organic impairment whereas the “dis” prefix implies deviant behavior. Accepting the somewhat controversial assumption that the prefixes are different, dysfluency (or “abnormal fluency”) is essentially synonymous with stuttering. However, most recent texts still prefer the term stuttering.
As noted, dysfluency is frequently used interchangeably with disfluency (see 3.3), although professional consensus suggests that the two terms are not necessarily synonymous.
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Given the diversity of professional opinion on what constitutes stuttering, the Task Force recommends that clinicians and researchers recognize and indicate which of the following four uses, or combinations thereof, of the term stuttering they refer to in their references to this fluency disorder. Two uses refer primarily to the behavior of stuttering, and two refer primarily to individuals who manifest the behavior. The first two are essentially perceptual definitions (i.e., defined by a listener), the first from a specific symptom orientation and the second from a nonspecific orientation. The third defines stuttering in terms of private experience of the person who stutters, and the fourth focuses on the suspected cause or nature of stuttering. In all cases, stuttering refers to a communication disorder related to speech fluency that generally begins during childhood (but, occasionally, as late as early adulthood). Some individuals refer to this typical stuttering as “developmental stuttering.” Others refer to stuttering as a “syndrome,” focusing thereby on a set of symptoms that may coexist in any stuttering individual. Neurogenic stuttering and psychogenic stuttering are special cases that are not sub-types of typical or “developmental” stuttering, despite the widespread use of these terms (see 3.12 and 3.13).
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This definition implies that certain categories of symptoms or disfluencies (see below) can generally be classified as abnormal and that others can be considered normal. With this definition, the fact that specific examples within any of the above disfluency categories may be variously perceived as normal or abnormal is generally disregarded. Also, the category of monosyllabic whole word repetitions is not always considered stuttering, depending on such variables as age of the client, locus within the utterance, duration, and other factors. This definition implies that stuttering occurs on specific language units (e.g., words or syllables).
This definition is intuitively appealing to clinicians for it renders stuttering a quantifiable phenomenon, suggests specific targets of treatment (i.e., the disfluency categories with the most stuttering), and allows for careful clinical descriptions of accessory (secondary) behaviors (see 3.6). It also has appeal for research, especially in determining beforehand which subjects will and will not be included in stuttering groups.
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This definition relies on operationalism, that is, defining a difficult concept by the operations used to measure it. Specifically, the definition implies that a listener or conversation partner does not require a specific orientation to identify instances of stuttering. One does so because he or she knows the language in question and can therefore identify abnormalities in its production. The operations involved are those that are quantifiable and that specify reliability assessments. The definer must demonstrate a reasonable degree of agreement with other “judges” on the measures taken, as well as with himself or herself in repeated assessments, in identifying specific instances of stuttering. This definition grants credibility to the obvious situation that one does not need to be trained to recognize stuttering, as is the case when laymen diagnose a stuttering problem. No doubt, speech events regarded as stuttering in the previous definition are responsible for most judgments of stuttering. Nevertheless, with this symptom-nonspecific definition, a “moment of stuttering” may, in some circumstances, be attributed to disfluency categories that, in other circumstances, would be regarded as normal, and vice versa. As in the previous definition, stuttering is quantifiable and allows for careful descriptions of accessory (secondary) behaviors.
This operational definition has appeal for clinicians who choose to use an approach in treatment requiring “on line” counts or immediate consequences or feedback to be provided immediately after each “moment of stuttering.” It is also particularly appealing to researchers who require reliable measures of stuttering.
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This definition focuses on the experience of the person who stutters rather than judgments of clinicians, observers, or theoreticians. The most vocal advocate of this view is Perkins (1990), who wrote that “stuttering is the involuntary disruption of a continuing attempt to produce a spoken utterance” in which “involuntary” is understood to reflect the speaker's feeling of “loss of control.” This orientation allows the clinician to appreciate the difference between “real” and “faked” stuttering and have a more inclusive definition for the client who claims to be a “stutterer” but overtly “stutters” only on rare occasions.
This definition has particular appeal to persons, especially adults, with a history of stuttering themselves because it describes what they experience as stuttering. It has been regarded by many to have questionable use alone in clinical and research efforts because objective, replicable judgments of stuttering are difficult or impossible to obtain.
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This is not a definition per se. Instead, it refers to numerous definitions such as the following: “Stuttering is an anticipatory, apprehensive, hypertonic avoidance reaction” (Johnson, Brown, Curtis, Edney, & Keaster, 1967); “Stuttering occurs when the forward flow of speech is interrupted by a motorically disrupted sound, syllable, or word or by the speaker's reactions thereto” (Van Riper, 1982); or “…stuttering constitutes a covert repair reaction to some flaw in the speech plan” (Kolk & Postma, 1997).
These definitions focus on theory construction and address the questions, “What causes stuttering?” and/or “What is the nature of stuttering?” Such definitions, to the extent that they balance available knowledge with available research technology, can lead to testable hypotheses about the nature of stuttering.
Cause-based definitions are appealing to many stuttering clients, especially those seeking “answers” or insights into their disorder. In some cases such definitions suggest new or specific approaches to treatment. By contrast, they are generally not suitable for measuring stuttering behaviors in clinical or research settings.
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As with the case of the “general” definition provided, a number of definitions of stuttering include elements of more than one of the above variants. For example, the World Health Organization (1977) defines stuttering as “disorders of rhythm of speech in which the individual knows precisely what he wishes to say, but at the time is unable to say it because of involuntary, repetitive prolongation or cessation of a sound.” The Diagnostic and Statistical Manual of Mental Disorders (4th ed., rev., 1994; DSM-IV) indicates that “the essential feature of stuttering is a disturbance in the normal fluency and time patterning of speech that is inappropriate for the individual's age.” Stuttering is characterized by “frequent repetitions or prolongations of sounds or syllables,” but also can include “interjections … broken words (e.g., pauses within a word) … audible or silent blocking (filled or unfilled pauses in speech) … circumlocutions (e.g., word substitutions to avoid problematic words) … and monosyllable whole word repetitions (e.g., ‘I-I-I-I see him’).” In addition, the DSM-IV requires that “the disturbance in fluency interferes with academic or occupational achievement or with social communication” and all these difficulties exceed those usually associated with a “speech-motor or sensory deficit,” if present.
Many individuals who stutter acquire maladaptive patterns of thinking and feeling, sufficiently common to be identified as frequent covert aspects of stuttering. For example, a child who stutters may adopt the belief that speaking is inherently difficult (Bloodstein, 1995). Those who stutter for a number of years often acquire the negative self-concept of “stutterer,” leading them to adopt other beliefs and attitudes consistent with this self-concept (Cooper, 1990; Peters & Guitar, 1991). Also, many stuttering children and adults report fear or anxiety about speaking, or the prospect of speaking; frustration from the excessive time and effort imposed by stuttered speech; embarrassment, shame, or guilt following stuttering episodes; and even hostility toward other conversation partners (Van Riper, 1982).
Stuttering is often used in lay usage to refer to disfluencies (see 3.3), both normal and abnormal. Also, many nonstutterers report that they have experienced stuttering of a sort they would regard as abnormal a few times in their lives.
In 1993, as the result of the influence of a number of consumer and self-help groups, the American Speech-Language-Hearing Association (ASHA) adopted a policy in which person-first language is to be used in lieu of direct labels (Executive Board Meeting Minutes, 1993). According to the policy, stutterer is regarded as potentially insensitive to the individual who manifests the problem of stuttering. Therefore, authors are required to use the term person who stutters instead of stutterer. Recent articles have tended to use abbreviations (e.g., PWS for person who stutters or CWS for child who stutters) to avoid the awkwardness inherent in using the longer versions.
No systematic research was carried out to support the ASHA “person-first” policy. Since its inception, limited research has shown that person-first labeling may or may not be perceived less negatively by individuals with speech-language-hearing impairments, parents of such clients, speech-language pathology students, and the public. In the case of the terms stutterer, stammerer, or clutterer, the results do not clearly indicate that these direct labels consistently communicate greater sensitivity than the person-first versions (Robinson & Robinson, 1996; St. Louis, 1998). More research is needed, but the available findings cast doubt on both the need and wisdom underlying the recent changes in terminology. Person-first labeling warrants serious consideration when referring to specific individuals, especially in clinical situations, for it implies that there is much more to a person than the fact that he or she stutters. On the other hand, given the fact that many nonstutterers report that they have occasionally “stuttered,” the person who stutters nomenclature may create ambiguity in descriptions of subjects in research reports wherein the traditional distinction between stutterer and nonstutterer is important. Until additional research is completed, clinicians or researchers will—and possibly should—use their own discretion in the use of those terms.
Stammering is synonymous with stuttering and is the common term for the disorder in Great Britain. In North America, the term stammering is rarely used by speech-language pathologists.
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Accessory (secondary) behaviors are typically considered to be reactions to stuttering that are reinforced by their initial consequences, which, according to the user, reduce the stuttering abnormality (escape) or prevent or delay its occurrence (avoidance/postponement). Accessory (secondary) behaviors are considered to be learned (although there is some evidence that some may not be learned), and the stutterer may or may not be aware of their presence. They include such categories as: “avoidance behaviors” (e.g., not speaking when one wants to [as in class discussions] or substituting synonyms for feared words or circumlocuting/paraphrasing the intended utterance), “postponement devices” (e.g., stalling by using nonword or word fillers or simply waiting to attempt to talk), “timing devices” or “starters” (e.g., blinking the eyes, taking a short gasp, or getting a “running start” in order to begin to say a feared word), “disguise reactions” (e.g., covering one's mouth or faking a cough in order to hide the fact that one is stuttering), “interrupter devices” (e.g., jerking the head or grimacing to release from a long block), and “searching movements” (e.g., using the schwa or inappropriate vowel or altering the rate of repeated sounds or syllables). In some cases, evidence of “struggle” (see 3.8) may be regarded as an accessory (secondary) behavior.
In general, the word “accessory” (or “secondary”) implies that the above listed behaviors and strategies accompany the core features of stuttering and that a causal account for these behaviors (i.e., learning) is implied. By contrast, when stuttering is considered to be a clinical syndrome, its affective, behavioral, and cognitive aspects (including strategies to hide and avoid the occurrence of stuttering) are considered to be integral components of the disorder rather than “accessory” (or “secondary”) behaviors.
Accessory (secondary) behaviors are also known as “secondary mannerisms,” “secondaries,” “concomitant behaviors,” or “extraneous behaviors.”
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Speech rate is typically expressed in words or syllables per minute. Generally, only the periods of time in which the speaker is actually talking are included in calculating rate, and these include normal pauses. (Most of these normal pauses are less than 1 second; longer inter-utterance pauses [e.g., 2 seconds or more] are typically excluded from rate assessments. There are reasonable exceptions to excluding long pauses in rate assessments, e.g., when the evaluator wishes to consider the time taken up by long pauses that are associated with avoidance. In such cases, the time spent actually stuttering is occasionally reported as well.) Some researchers use the measure of “articulation rate” (also known as “phone rate” or “phoneme rate”), which is calculated from short periods of fluent speech that are free of perceptible pauses. This measure is often reported in syllables per second.
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Every speech act requires the speaker to exert some effort. The degree of effort required varies with such aspects as the speaker's familiarity with the language, topic, and listener(s); interference from internal and external sources; and individual differences in the capacity for fluent speech. The speaker's total effort includes both physiological and psychological components. Moreover, physiological and psychological effort interact with each other as in the cases wherein heightened emotion or certain thoughts result in excessive muscle tension. Similarly, cautious or overcontrolled speech may be characterized by inappropriate and/or excessive tension levels. “Struggle” is a special case of effort and refers to speech events that are characterized by unusual and/or excessive amounts of (physiological and/or psychological) effort during the production of some—but generally not all—sounds, words, or longer utterances. Effort can be considered both from the perspective of the speaker (i.e., the level of effort experienced during speech) or from the perspective of the listener (i.e., the degree of effort the listener attributes to the speaker's performance). It should be noted that some authorities prefer the term “ease” to effort because fluency generally has a connotation of “easy” rather than “hard” or “effortful.”
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Certain prosodic features, such as intonation patterns that extend across several segments, are suprasegmental in nature. Similarly, an alteration of stress on a compound word (e.g., base'ball versus baseball') is a suprasegmental feature change.
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Although related to “continuity” and rate, rhythm is more specific. It refers to the degree that a speaker's pattern of syllable stress in words and sentences is similar to a standard or predicted pattern. In other words, normal rhythm refers to maintaining a perceptibly appropriate pattern of “beats” and pauses at an acceptable rate. Deviations in rhythm may be perceived as variations in the “regularity of rate.” Different languages have different characteristic rhythms, sometimes readily recognized by individuals listening to a conversation in a language they do not know. Moreover, the same language may have several normal variations in rhythm. For example, it is possible for a speaker to produce speech characterized by normal continuity and rate, but which violates the conversational stress pattern of the language or specific dialect in question (e.g., General American English). One such case pertains to numerous English speakers from India and Pakistan, who are often perceived to be quite fluent but not easily understood by native English speakers from North America unfamiliar with their variant of English. In this case, differences in the rhythm of the variants of English are partly responsible for the difficulty in understanding.
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Prosody is related to rhythm in that both concepts include consideration of patterns of syllable stress and pauses. Prosody also includes the element of fundamental frequency changes related to intonation. Syllable stress refers to greater intensity, slightly higher fundamental frequency, and longer durations on certain syllables, as in “I' live in the white house” versus “I live' in the white house.” Juncture, among other things, refers to subtle differences in the length of pauses between words, as in “I live in the white house.” versus “I live in the White House” (dwelling of the U.S. president). Intonation contours refer to meaningful frequency variations on words, phrases, and longer utterances, as in “I live in the white house” (i.e., “I do live there”) versus “I live (in the white house?” (i.e., Do I live there?”). As a term for description of some aspect of fluency, prosody suffers from a lack of agreed-on specificity.
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Naturalness is a global measure and has been typically determined by playing samples of speech to a group of normal listeners and asking them to judge how natural the speech sounds according to a 9-point equal-appearing interval scale (Martin, Haroldson, & Triden, 1984). In ways that are not well understood, naturalness as a measure in fluency disorders is related to ratings of overall disorder severity, fluency, rhythm, rate, and prosody. Whereas persons with mild stuttering may have “natural-sounding speech,” the degree of naturalness perceived by the listener usually decreases (i.e., becomes more “unnatural”) as stuttering becomes more severe.
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Cluttering is a term that describes a constellation of symptoms, including fluency problems. Most of the early writing on cluttering grew out of the European traditions of phoniatrics and logopedics. Except for isolated publications, cluttering was generally ignored in North America until recently. The definition of cluttering is not clearly established, but most current authorities agree that deficits in fluency, rate, and coexisting disorders of language and/or articulation are nearly always present. Problems in such areas as attention, activity level, reading, and handwriting suggest strong parallels between cluttering and “learning disabilities” and “attention-deficit/hyper-activity disorders.”
Generally, the disfluencies observed in clutterers consist of those typically regarded as “normal” or “ambiguous,” referred to earlier. Cluttering may occur alone as a fluency disorder, but it more frequently coexists with stuttering.
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Generally, neurogenic stuttering is observed in adults who have undergone confirmed brain damage. An infrequently occurring disorder, it has been observed in individuals who have lesions in diverse areas of the central nervous system (e.g., Helm-Estabrooks, 1993). Neurogenic stuttering has been labeled variously as “acquired stuttering,” “stuttering secondary to brain damage,” and “cortical stuttering.” Some in the professional community question whether neurogenic stuttering is a valid diagnostic entity.
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Psychogenic stuttering refers to stuttering that is the primary symptom of some form of verifiable psychopathology, such as a neurotic conversion disorder (e.g., Roth, Aronson, & Davis, 1989). Excluded from this somewhat questionable category is stuttering that began after a psychologically traumatic event because, in most cases, the stuttering symptoms continue to develop in much the same way as do symptoms of stuttering that began in childhood after no such traumatic event. The Task Force cautions researchers and clinicians to use the term psychogenic stuttering only in cases in which it is clearly related to diagnosed psychopathology. Some in the professional community question the validity of psychogenic stuttering as a diagnostic entity.
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