Sound Prolongations Research Articles

Genetic Susceptibility to Stuttering

Disorders that disrupt the development of speech, language, or reading have substantial effects on social function. Researchers have implicated specific genetic variants in monogenic speech disorder,1 common language impairments,2,3 and dyslexia.4 With the report by Kang and colleagues in this issue of the Journal, 5 stuttering joins the fray. Stuttering is a disorder in which speech fluency can be severely compromised. It is characterized by the involuntary repetition or prolongation of sounds, syllables, words, or phrases, as well as frequent pauses, impeding the rhythmic flow of speech. Onset is typically between 3 and 6 years of age, and approximately 5% . . .

Exploratory Randomized Clinical Study of Pagoclone in Persistent Developmental Stuttering

Stuttering is a speech disorder in which the flow of speech is disrupted by repetitions, prolongation, and blocks of sounds, syllables, or words. No pharmacological treatments are approved for use in stuttering, and the most common form of treatment is speech therapy. This study was designed to assess the safety, tolerability, and effectiveness of pagoclone during 8 weeks of double-blind treatment followed by a 1-year open-label extension in patients who stutter. An 8-week, multicenter, parallel-group, 2-arm, randomized (ratio 2:1 pagoclone-placebo), double-blind study with a 1-year open-label extension conducted at 16 US centers, including men and women aged 18 to 65 years who developed stuttering before 8 years of age. Twice-daily dosing with pagoclone (n = 88 patients) or matching placebo (n = 44 patients), with primary and secondary efficacy variables defined a priori, including Stuttering Severity Instrument Version 3 outcomes, clinician global impressions of improvement, and the change in the percentage of syllables stuttered. Pagoclone produced an average 19.4% reduction in percentage of syllables stuttered compared with 5.1% reduction for placebo. During open-label treatment, a 40% reduction in the percent syllables stuttered was observed after 1 year of treatment with pagoclone. The most commonly reported adverse event during double-blind treatment was headache (12.5% pagoclone patients, 6.8% placebo patients). Pagoclone was effective in reducing symptoms of stuttering and was well tolerated. In light of its favorable tolerability profile, as well as consistency of effects across multiple efficacy variables, pagoclone may have potential as a pharmacological treatment of stuttering. The main limitation of this study was the adequacy of the number of subjects who participated because this study was conducted as a pilot investigation. Furthermore, as this condition waxes and wanes, the assessment of stuttering within the clinic setting may not be an adequate reflection of the stuttering of the patients within the community.

STUTTERING THERAPY FOR A CHILD AT INTERMEDIATE STUTTERING LEVEL

Abstract Stuttering therapy very often demands combination of various approaches or its modification. The main purpose of this study was to present an integrated approach to stuttering modification therapy and fluency shaping therapy for an intermediate school-age male stutterer (11 years old). The therapy for the child lasted for 12 months, sessions have been carried out twice a week, each session lasted for 45 minutes. The child still attends the therapy. The therapy uses integration of stuttering modification therapy and fluency shaping therapy. For the purpose of the fluency shaping therapy, delayed auditory feedback program is applied. During the stuttering modification therapy the child has been taught how to stutter more easily which implies prolongation of all sounds in words on which child stutters, with easy and soft transition from one sound to another. It is continuously being worked with the child on reducing negative feelings and attitudes as well as elimination of avoidance of words and speaking situations. We explained to the parents the treatment program and their role in the program realization. We also explained the possible causes of stuttering, and tried to identify and reduce fluency distractors, and engage the child in as many situations as possible which improved speech fluency. After the application of this program the child has improved fluency during the conversation in clinical and nonclinical conditions (environment). This fluency consists of spontaneous and controlled fluency. Furthermore, fear of speaking and avoidance of speech situations are significantly reduced. On the basis of the applied therapy on the child at intermediate stuttering level it can be concluded that it is possible to integrate successfully both approaches: stuttering modification therapy and fluency shaping therapy. Key words: stuttering, stuttering therapy, stuttering modification, fluency shaping. (ProQuest: ... denotes non-US-ASCII text omitted.) Introduction Stuttering comprises breaks in speech fluency and is characterized by an abnormally high frequency and/or duration of stoppages in the flow of speech. These stoppages usually take the following forms: repetitions of sounds, syllables or one-syllable words; prolongations of sounds or "blocks" of airflow. Stuttering individuals are aware of their stuttering and very often are embarrassed by it. They use abnormal physical and mental effort to speak (1). Assessment of stuttering severity includes subjective assessment and stuttering is usually classified as mild, moderate, and severe (2). Different therapy approaches are useful for different subjects (3). There have been three treatment paradigms used with stuttering: direct treatment, indirect treatment and a combination of direct and indirect methods (4). The most often used therapy approaches are: stuttering modification therapy and fluency shaping therapy. Stuttering modification therapy involves teaching the child how to modify his/her moments of stuttering, how to reduce tension and frequency of stuttering and to stutter in more relaxed and easier manner. The goal of fluency shaping therapy is to increase fluent responses systematically until the client replaces stuttering moment with fluent speech or achieve fluency by altering speech pattern. This may involve that stuttering client speaks at a substantially slower speech rate (1). Rate reduction often emphasizes the use of prolonged speech in which the duration of articulatory moments is increased and smooth articulatory transitions between sounds and syllables are accentuated. Such slowing and smoothing of speech promotes the coordination and integration of respiratory, phonatory and articulatory movements. Once such movements are well learned and integrated, the client is able to gradually increase speed of performance, often without fluency breaks (5). Stuttering modification therapy and fluency shaping therapy are not antagonistic approaches and can be succesfully integrated. …

Phonotactic probability effects in children who stutter.

The purpose of this study was to examine the influence of phonotactic probability, which is the frequency of different sound segments and segment sequences, on the overall fluency with which words are produced by preschool children who stutter (CWS) as well as to determine whether it has an effect on the type of stuttered disfluency produced. A 500+ word language sample was obtained from 19 CWS. Each stuttered word was randomly paired with a fluently produced word that closely matched it in grammatical class, word length, familiarity, word and neighborhood frequency, and neighborhood density. Phonotactic probability values were obtained for the stuttered and fluent words from an online database. Phonotactic probability did not have a significant influence on the overall susceptibility of words to stuttering, but it did impact the type of stuttered disfluency produced. In specific, single-syllable word repetitions were significantly lower in phonotactic probability than fluently produced words, part-word repetitions, and sound prolongations. In general, the differential impact of phonotactic probability on the type of stuttering-like disfluency produced by young CWS provides some support for the notion that different disfluency types may originate in the disruption of different levels of processing.

Phonological neighborhood and word frequency effects in the stuttered disfluencies of children who stutter.

The purpose of this study was to examine (a) the role of neighborhood density (number of words that are phonologically similar to a target word) and frequency variables on the stuttering-like disfluencies of preschool children who stutter, and (b) whether these variables have an effect on the type of stuttering-like disfluency produced. A 500+ word speech sample was obtained from each participant (N = 15). Each stuttered word was randomly paired with the firstly produced word that closely matched it in grammatical class, familiarity, and number of syllables/phonemes. Frequency, neighborhood density, and neighborhood frequency values were obtained for the stuttered and fluent words from an online database. Findings revealed that stuttered words were lower in frequency and neighborhood frequency than fluent words. Words containing part-word repetitions and sound prolongations were also lower in frequency and/or neighborhood frequency than fluent words, but these frequency variables did not have an effect on single-syllable word repetitions. Neighborhood density failed to influence the susceptibility of words to stuttering, as well as the type of stuttering-like disfluency produced. In general, findings suggest that neighborhood and frequency variables not only influence the fluency with which words are produced in speech, but also have an impact on the type of stuttering-like disfluency produced.

The need for self‐report data in the assessment of stuttering therapy efficacy: repetitions and prolongations of speech. The stuttering syndrome

Bloodstein reviewed hundreds of studies that investigated the efficacy of therapeutic protocols for ameliorating the stuttering syndrome. Surprisingly, almost all were effective in significantly reducing overtly perceptible behaviours such as repetitions and prolongations of speech sounds. These results seem highly improbable considering that many of the treatment methods were diametrically opposed in their principles and implementation procedures (e.g. psychoanalysis, drug therapy, behaviourism, cognitive behavioural therapy and auditory feedback devices with rate control, etc.). In addition, time and more ecologically valid methods such as self-report measures demonstrate that overt measures of success are tenuous, their ameliorative effects tend to diminish drastically over time and show poor generalizability. Further, the real conundrum in stuttering therapy is the failure to acknowledge stuttering as a complete syndrome of continuous compensatory behaviours. To highlight how self-report measures serve as a primary tool to understand the syndrome-like nature of stuttering and to test the efficacy of the therapy outside the confines of the clinic and the needs of the people who stutter. In the past, therapeutic efficacy has typically been measured by the reduction in overtly observable and countable events of stuttering such as repetitions and prolongations. However, recent neuroimaging data and our research suggest that the stuttering syndrome is more than the mere presence of peripheral speech disruptions. Stuttering is a central, experiential sense of 'loss of control' that manifests itself across a continuum of compensatory behaviours from the central nervous system outwards to the speech periphery. In other words, aberrant neural activity, as well as covert stuttering behaviours, subperceptual stuttering forms and overt speech disruptions are all effects or compensations for the central involuntary 'neural block'. Hence, by counting only perceptible portions of the disorder, efficacy measures 'fail to capture' the experiential sense of 'loss of control' and the covert compensatory behaviours of the disorder (i.e. avoidances of words or situations, substitutions, circumlocutions, subperceptual stuttering forms, etc.). Furthermore, unnatural sounding speech, decreased ease of speech production, elevated levels of clinic room fluency and poor reliability in counting stuttering behaviours confound the overt measures in the clinic milieu. Therefore, while overt measures remain important, used in isolation, they cannot provide a 'true metric' of efficacy. Any efficient and effective means of evaluating intervention methods over the long-term should include a form of self-report as a primary tool as it best accesses the experiential sense of 'loss of control' and other covert behaviours. Overt measures should be used to supplement or complement the self-report data.

Regulated breathing as a treatment for stuttering: A review of the empirical evidence.

Abstract Regulated Breathing (RB) is a behavioral treatment for stuttering designed to address airflow irregularities by teaching breathing patterns that are incompatible with stuttering. The current paper describes the RB procedure and reviews published literature to examine the empirical support for the efficacy of RB. Existing data indicate that RB is an effective treatment for stuttering and could be considered a probably efficacious treatment according to the criteria described by Chambless and Ollendick (2001). Limitations of the present literature are discussed, as well as suggestions and possible directions for future research. Keywords: Regulated Breathing, Stuttering. Introduction Stuttering is characterized by a disturbance in the normal fluency and time patterning of speech (APA, 2000). Speech disturbances include frequent occurrences of sound, syllable, and whole-word repetitions; sound prolongations or hesitations; interjections; broken words; or circumlocutions. The Diagnostic and Statistical Manual of Mental Disorders includes the criterion that stuttering interferes with academic, occupational or social functioning and must not be better accounted for by a speech-motor or sensory deficit (APA, 2000). However, a diagnosis of stuttering in young children is often given even in the absence of functional impairment. When young children are diagnosed, speech patterns are usually evaluated and compared to the normal fluency for their age group (APA, 2000). Clinicians also take into consideration developmental and emotional factors that can disrupt a child's speech (Williams, 1985). Prevalence rates of stuttering are approximately 1% (Bloodstein, 1995) but can be as high as 5% during childhood (Leung & Robson, 1990). The onset of stuttering usually occurs between the ages of 2 and 6 (Andrews et al., 1983; Homzie & Lindsay, 1984) and is more common in males. The male-to-female gender ratio is 3 to 1 during childhood and increases to 5 to 1 in adulthood (APA, 2000, Bloodstein, 1995). Although a specific cause for stuttering is not known, it is believed to be a heritable disorder (Felsenfeld et al., 2000; Andrews, Morris-Yates, Howie, & Martin, 1991). Stuttering is associated with various airflow irregularities. Healey (1991) suggested that stuttering is primarily associated with the tightening of the laryngeal muscles in the throat, resulting in a disruption of airflow and speech production, and Bloodstein (1995) noted that in some cases a complete cessation of breathing or an irregularity of the respiratory cycle occurs during stuttering. Also, people who stutter tend to have less airflow during speech difficulties involving the coordination of laryngeal muscles, which results in decreased air volume in the lungs before speech initiation (Stager, Denman, and Ludlow, 1997). To address the issue of airflow irregularities in stuttering, modification of speech-related respiratory behavior is believed to be useful in the treatment of the disorder. Description of Regulated Breathing Regulated Breathing (RB) is a multicomponent behavioral treatment that attempts to inhibit stuttering by teaching a speech-related breathing pattern that is incompatible with stuttering (Azrin & Nunn, 1973). RB consists of several different treatment components, including awareness training, relaxation, competing response training, motivation training, and generalization training. It shows significant overlap with habit reversal, a procedure designed to treat nervous habits and motor tics. Awareness Training. Awareness training is comprised of four techniques. During response description, the client deliberately stutters and provides a detailed verbal description of physical movements, sounds, and sensations (tension) associated with his or her stuttering. The second awareness technique, response detection, requires a client to point out a stutter when it occurs. …

The effects of differential vowel prolongations on perceptions of speech naturalness

Prolongation of speech sounds is currently used to modify stuttering and enhance fluency. Prolonged speech (PS) (e.g., prolonged vowels, prolongation throughout utterances) is, however, often perceived as unnatural by listeners. This study examined at which durations and in which contexts 52 college students (primary language was American English) perceived PS to be unnatural. Stimuli were limited to controlled variation in prolongation of the vowel in the middle single-syllable word of a carrier phrase (i.e., say word again). The prolongation was effected by digital waveform manipulation within the Kay Elemetrics Computerized Speech Laboratory (CSL). The listeners judged if they strongly agreed, agreed, or disagreed that the phrases sounded natural. Results indicated that the extent of vowel duration (and possibly context) does influence listener's perception of speech naturalness, findings which can be applied to facilitate fluency therapy. Educational objectives: (1) The reader will learn about and be able to summarize the digital waveform manipulation procedure in the study. (2) The reader will learn about and be able to describe the effects of differential vowel prolongation on listener's perception of speech naturalness. (3) The reader will learn about and evaluate how differential vowel prolongation can be used to enhance fluency.

Neurobiology of speaking and stuttering

A multi-level model of speech motor control including the word, syllable and phonem level is proposed, which takes into account linguistic, technical, biological, physiological and developmental aspects. Crucial point is the double function of the vowel onset, which serves to control vowel length and also to synchronize the serialization of words into temporal strings of syllables. In (long) stressed syllables this is done via auditory feedback (re-afferent control), while the utterance of unstressed syllables is automatized using internal signals (efferent control). Young children's problem when crossing from infantil to adultlike speech is to learn to inhibit re-afferent and to apply efferent control of unstressed syllables. If this task is learned incompletely, the model predicts stuttering, e.g. speech blocks, or repetitions and prolongations of syllables or phonems. Because all these control and learning processes refer to low level motor control, the model also contributes to unburden persons who stutterer and their parents from personal responsibility for the occurence of this communication disorder. FACTS, THEORIES AND BELIEVES CONCERNING STUTTERING Basic symptoms of stuttering are repetitions of words or syllables or parts of them, prolongations of speech sounds (phonems), and blockades. All of young children aged between two and five years use to have normal dysfluencies (Yairi 1981, 1997, Froschels 1952), but about 5% of the children show the basic symptoms of stuttering mentioned above. Many of the children lose these dysfluencies until puberty. In the end, about 1% of the adult population exhibits, regardless of culture and language, persistent speech dysfluencies, now three times more male than female people. Stuttering often is detrimental for personal achievement, social contacts, carreer, and self-esteeme, therefore, almost all people who stutter participated in at least one therapy, whereby, however, stuttering often cannot be cured completely, or re-appears later on. Explanations of the symptoms of stuttering usually start from investigations referring to sensory feedback of self produced speech, especially to the effects of delayed auditory feedback (Lee 1951). Usually, nonstuttering persons exhibit repetitions of syllables and words under this experimental manipulation, whereby delay times between 100 and 300 ms are most effective. Paradoxically, symptoms diminish in stutterers under delayed auditory feedback, at least at the beginning of application (Bergmann 1987). Occasionally, also auditory masking by loud noise applied through headphones facilitates fluent in stutterers (Bergmann 1987). Fluency enhancement in stutterers is also reported when using frequency shifted auditory feedback (Howell et al 1987, Natke & Kalveram, in press). Because of such studies, it is concluded (e.g. Van Riper 1982, Perkins et al. 1976, Adams 1974) that during speech development the auditory feedback channel gradually loses influence on speech control, until, in adults, only tactile-proprioceptive feedback is used for purposes of control. Speech dysfluencies, then, originate from auditory feedback not sufficiently being suppressed. This may lead to interferences and/or discoordinations between different feedback channels, which disturbes the auto-regulation of speaking (Fiedler & Standop 1992). However, experiments of Bauer et al. (1997) do not support interference models of stuttering. In these experiments, irregular tactile and proprioceptive feedback was artificially generated through mechanical disturbations of the jaw movement during speaking. These disturbations neither led to significant changes of speech relevant parameters of the acoustical speech signal, nor differentiated between stutterers and non-stutterers. Furthermore, experiments with manipulated auditory feedback (see also the chapter concerning audiophonatory coupling) show that the auditory feedback channel is not at all switched off during speaking, neither in stutterers nor in fluent speakers. Therefore, it can be argued that auditory, not proprioceptive, feedback is of particular importance for speech flow control, 1 Supported by grants Ka417/13-1 to -3 from Deutsche Forschungsgemeinschaft (DFG)

Individual and Consensus Judgments of Disfluency Types in the Speech of Persons Who Stutter

Previous research has suggested that the reliability with which judges identify individual disfluency types, such as repetitions or prolongations of speech sounds, may be very poor. The use of disfluency types judgments in research and clinical applications is also complicated by important differences among the several disfluency-based characterizations of stuttered speech. In an attempt to address these problems, this study arranged for 30 judges to identify all disfluency types that they perceived to be present in 5-s audiovisually recorded speech stimuli, each in an Individual task and then with a partner in a Consensus task. Intrapair agreement and interpair agreement for occurrences of disfluency types (from Consensus conditions) were significantly higher than intrajudge and interjudge agreement for occurrences (from Individual conditions). Despite being higher than individual values, however, intrapair and interpair agreement for occurrences both averaged less than 50%. Results also showed that disfluency types judgments, interpreted in terms of three common disfluency-based definitions of stuttering, were not strongly related to previous assessments of whether these speech tokens contained or did not contain stuttering. When combined with previously available data, the present findings suggest caution in the use of disfluency types to describe or define stuttered speech.

Comparing real-time and transcript-based techniques for measuring stuttering

The purpose of this study was to compare results obtained from two different techniques for counting speech disfluencies. Fifty audio-videotaped speech samples were analyzed using: (a) a transcript-based technique designed to evaluate speech (dis)fluency in the context of a speaker’s conveyed message and (b) a real-time technique designed to rapidly determine the frequency of various types of speech disfluencies in conversational speech. Results obtained using these two techniques were quite similar, though there were some consistent and predictable differences associated with the presence of brief sound prolongations and more complicated disfluency clusters. Further analysis revealed that the two measurement techniques resulted in substantially different severity ratings for only two of the 50 speech samples. Findings provide support for a comprehensive measurement strategy in which clinicians utilize a transcript-based approach when more detailed information is needed (e.g., during diagnostic evaluations) and a real-time approach for documenting on-going changes in clients’ speech behaviors (e.g., during treatment).

Duration of Sound Prolongation and Sound/Syllable Repetition in Children Who Stutter

The purpose of this study was to measure the duration of sound prolongations and sound/syllable repetitions (stutterings) in the conversational speech of school-age children who stutter. The relationships between duration and (a) frequency and type of speech disfluency, (b) number and rate of repeated units per instance of sound/syllable repetition, (c) overall speech rate, and (d) articulatory rate were also examined. Results indicated that for the children in this study the average duration of stuttering was approximately three-quarters of a second, and was not significantly correlated with age, length of post-onset interval, or frequency of speech disfluency. In addition, findings can be taken to suggest that part of the clinical significance of stuttering duration for children who stutter might lie in its relationship to the amount of sound prolongations these children produce, as well as their articulatory rate during fluent speech.

Coexistence of stuttering and disordered phonology in young children.

The purpose of the present study was to assess differences in stuttering, phonological, and diadochokinetic behaviors in young children who exhibit both stuttering and disordered phonology and children who exhibit only one of the disorders. Subjects were 21 male children (aged 4 to 6 years), representing three groups of seven children each: (a) stuttering and normal phonological abilities (S+NP), (b) stuttering and disordered phonology (S+DP), and (c) normal fluency and disordered phonology (NF+DP). Stuttering behavior was assessed during a 30-minute conversational speech task; phonological behavior was assessed during a 162 item picture-naming task; and diadochokinetic abilities were assessed during bi- and multisyllable productions. Results indicated that the S+DP group produced significantly more sound prolongations and significantly fewer iterations per whole-word repetition than the S+NP group. However, there were no differences between the two groups in other stuttering indices. Moreover, no differences were noted between the S+DP and NF+DP groups in phonological behavior. Diadochokinetic rates did not differ among the three groups. The possibility of two types of stuttering, one occurring with and one without disordered phonology, is discussed.

Maximum performance tests in children with developmental spastic dysarthria.

Three noninvasive Maximum Performance Tasks (MPT)--Maximum Sound Prolongation (MSP), Fundamental Frequency Range (FFR), and Maximum Repetition Rate (MRR)--were administered to 11 children with spastic dysarthria due to cerebral palsy and to 11 control children with normal speech in order to determine the value of the tasks for differentiating between these groups of children. From the acoustic measurements, nine parameters were calculated, and in seven of them highly significant group differences were found. By adding the unweighted z-scores of four parameters (maximum sound prolongation, syllable duration, fundamental frequency range, inter-utterance variability of syllable duration), a composite z-score was constructed with nonoverlapping distributions for both groups. The authors conclude that maximum performance tasks, despite the large intrasubject and intersubject variability in both normal and pathological speakers, are powerful tools for detecting spastic dysarthria.

Duration of the Speech Disfluencies of Beginning Stutterers

This study compared the duration of within-word disfluencies and the number of repeated units per instance of sound/syllable and whole-word repetitions of beginning stutterers to those produced by age- and sex-matched nonstuttering children. Subjects were 10 stuttering children [9 males and 1 female; mean age 4:1 (years:months); age range 3:2-5:1), and 10 nonstuttering children (9 males and 1 female; mean age 4:0; age range: 2:10-5:1). Mothers of the stuttering children reported that their children had been stuttering for 1 year or less. One 300-word conversational speech sample from each of the stuttering and nonstuttering children was analyzed for (a) mean duration of sound/syllable repetition and sound prolongation, (b) mean number of repeated units per instance of sound/syllable and whole-word repetition, and (c) various related measures of the frequency of all between- and within-word speech disfluencies. There were no significant between-group differences for either the duration of acoustically measured sound/syllable repetitions and sound prolongations or the number of repeated units per instance of sound/syllable and whole-word repetition. Unlike frequency and type of speech disfluency produced, average duration of within-word disfluencies and number of repeated units per repetition do not differentiate the disfluent speech of beginning stutterers and their nonstuttering peers. Additional analyses support findings from previous perceptual work that type and frequency of speech disfluency, not duration, are the principal characteristics listeners use in distinguishing these two talker groups.

Behaviors at the onset of stuttering

The purpose of this investigation was to identify speech and nonspeech behaviors associated with the stuttering of children close to the onset of their problem. Ten stuttering children (nine boys and one girl) were identified through a) parent interviews indicating that these children begun stuttering during the previous 12 months prior to data collection, and b) the presence of 3 or more stutterings per 100 words of conversational speech. Fourteen associated speech and nonspeech behaviors and speech dysfluency type were identified and quantified for 10 stutterings from each of the 10 subjects. The 14 associated behaviors and speech dysfluency type were further reduced to form three indices: a) Sound Prolongation Index, b) Nonspeech Behavior Index, and c) Behavioral Variety Index. Results indicated that all of the children exhibited speech and nonspeech behaviors in association with their stuttering. Additionally, chronological age did not significantly correlate with any of the three indices investigated. Findings are taken to suggest that the quantification of speech dysfluency type and the speech and nonspeech behaviors associated with stuttering are more sensitive than chronological age as indicators of the development of stuttering.

Judgments of disfluency by mothers of stuttering and normally fluent children.

The purpose of this study was to examine the relation between selected aspects of speech disfluency and perceptual judgments of these events by mothers of young stutterers and mothers of age- and sex-matched normally fluent children. Each mother independently listened to and judged as either "stuttered" or "not stuttered" recorded examples of a young stutterer's imitated productions of: (a) five different types of speech disfluency, (b) sound prolongations, and (c) sound/syllable repetitions of five different durations each, along with a comparable number of fluent utterances. Results indicated that although some between-group differences in judgments were observed, both groups most frequently judged sound/syllable repetitions to be stuttered, followed by whole-word repetitions and broken words. Fluent utterances, interjections, and sound prolongations were most frequently judged to be not stuttered by all mothers. Both groups judged sound prolongations averaging 258 ms in duration to be stuttered an average of 25% of the time, increasing to 68% for sound prolongations averaging 1254 ms; however, both groups of mothers judged sound/syllable repetitions of two or more iterations to be stuttered an average of 93% of the time. Findings suggest that there are not appreciable differences between mothers of stuttering and normally fluent children regarding their perceptual judgments of speech disfluencies, but each group might more frequently judge as stuttered those types of speech disfluencies characteristic of their own children's speech.

Acoustic and perceptual correlates of adult stutterers' typical and imitated stutterings

The purpose of the present study was to assess differences between selected acoustic correlates of adult stutterers' self-judged “uncontrolled” (typical) and “controlled” (imitated) stutterings. Subjects were nine adult stutterers (two female and seven male) with a mean age of 36 years and 2 months (range: 19–51 years) and a mean stuttering frequency of 19.26 stutterings (range: 5.4–32.0) per 100 words of conversation. Six temporal acoustic measures (phrase, stuttered word, stuttered segment, stop-gap, frication, and aspiration duration) were made for each subject's typical stutterings and a corresponding imitated version. No significant differences were found between stutterers' self-perceived typical versus imitated productions for any of the six temporal acoustic measures for all stutterings and for the two major types of stutterings in the sample (sound/syllable repetitions and sound prolongations). Further descriptive analysis indicated that stutterers were generally more certain of their perceptual judgments of controlled stutterings than they were of their uncontrolled stutterings. Although findings suggest that there are no apparent objective correlates of adult stutterers' self-perceived (controlled and uncontrolled stutterings), further study of these perceptions appears warranted.

Subgrouping young stutterers: preliminary behavioral observations.

The purpose of this investigation was to identify speech and nonspeech behaviors associated with stuttering of young persons and to use these behaviors in attempts to discern and describe subgroups of these individuals. Forty-three young stutterers (10 girls and 33 boys) produced stutterings and associated behaviors during conversations that were video/audio recorded. Fourteen associated speech and nonspeech behaviors and speech disfluency types were identified and quantified for 10 stutterings from each of the 43 subjects. The 14 associated behaviors and speech disfluency types were further reduced to form three related indices: (a) Sound Prolongation Index, (b) Nonspeech Behavior Index, and (c) Behavioral Variety Index. Results indicated that five subgroups of young stutterers could be identified and described on the basis of these youngsters' number and variety of speech and nonspeech behaviors associated with their stuttering. Findings are taken to suggest that these speech and nonspeech behavioral differences reflect differences in young stutterers' reactions and adjustments to their problem.

Stuttering and Stammering

Stuttering is a disorder characterized by intermittent difficulty in producing a smooth flow of speech. Stutterers may repeat or prolong sounds or may sometimes be unable to utter any sound without a great deal of effort. The disorder usually begins a year or two after the child has first learned to speak. The earliest symptoms are usually repetitions of parts of words. Signs of the problem may gradually progress, in a matter of months or during a period of several years, from these minor repetitions to prolongations of sounds, longer hesitations, and complete blockings of speech. Accessory signs and symptoms such as facial squeezing, tremors of the speech musculature, and eye blinks, as well as fear and avoidance of particular words and situations, often occur in more severe cases. At times stuttering may be