Screening for Speech and Language Delay and Disorders in Children 5 Years or Younger: Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance

Children with speech and language difficulties are at risk for learning and behavioral problems.

Objective

To review the evidence on screening for speech and language delay or disorders in children 5 years or younger to inform the US Preventive Services Task Force.

Data Sources

PubMed/MEDLINE, Cochrane Library, PsycInfo, ERIC, Linguistic and Language Behavior Abstracts (ProQuest), and trial registries through January 17, 2023; surveillance through November 24, 2023.

Study Selection

English-language studies of screening test accuracy, trials or cohort studies comparing screening vs no screening; randomized clinical trials (RCTs) of interventions.

Data Extraction and Synthesis

Dual review of abstracts, full-text articles, study quality, and data extraction; results were narratively summarized.

Main Outcomes and Measures

Screening test accuracy, speech and language outcomes, school performance, function, quality of life, and harms.

Results

Thirty-eight studies in 41 articles were included (N = 9006). No study evaluated the direct benefits of screening vs no screening. Twenty-one studies (n = 7489) assessed the accuracy of 23 different screening tools that varied with regard to whether they were designed to be completed by parents vs trained examiners, and to screen for global (any) language problems vs specific skills (eg, expressive language). Three studies assessing parent-reported tools for expressive language skills found consistently high sensitivity (range, 88%-93%) and specificity (range, 88%-85%). The accuracy of other screening tools varied widely. Seventeen RCTs (n = 1517) evaluated interventions for speech and language delay or disorders, although none enrolled children identified by routine screening in primary care. Two RCTs evaluating relatively intensive parental group training interventions (11 sessions) found benefit for different measures of expressive language skills, and 1 evaluating a less intensive intervention (6 sessions) found no difference between groups for any outcome. Two RCTs (n = 76) evaluating the Lidcombe Program of Early Stuttering Intervention delivered by speech-language pathologists featuring parent training found a 2.3% to 3.0% lower proportion of syllables stuttered at 9 months compared with the control group when delivered in clinic and via telehealth, respectively. Evidence on other interventions was limited. No RCTs reported on the harms of interventions.

Conclusions and Relevance

No studies directly assessed the benefits and harms of screening. Some parent-reported screening tools for expressive language skills had reasonable accuracy for detecting expressive language delay. Group parent training programs for speech delay that provided at least 11 parental training sessions improved expressive language skills, and a stuttering intervention delivered by speech-language pathologists reduced stuttering frequency.

Episodic stuttering as the presenting manifestation of acute ischemic stroke: A case report and systematic literature review

BACKGROUND

Acquired episodic stuttering in adulthood represents a rare condition, which has been infrequently described in the literature.

CASE PRESENTATION

We describe the case of a 62-year-old male who presented to the emergency room with three episodes of new-onset brief isolated stuttering with no other speech impairment or associated focal neurologic deficits. His brain magnetic resonance imaging was notable for the presence of a small acute ischemic stroke involving the left precuneus cortex.

SYSTEMATIC LITERATURE REVIEW

We performed a systematic literature review to evaluate the association between stroke and acquired neurogenic stuttering. The evidence published to this date suggests that the underlying pathophysiology of acquired stutter does not localize to an isolated or focal region. The development of stuttering secondary to strokes may be the result of a disruption at any level in a cortico-striato-cortical integrative pathway mediating speech execution.

CONCLUSION

Here we aimed to emphasize the importance of carefully evaluating new-onset recurrent episodic stuttering to rule out an underlying stroke or another neurogenic etiology. We provide a comprehensive review of acquired stuttering, its differential diagnosis, and its evaluation.

Stuttering-Like Dysfluencies as a Consequence of Long COVID-19

PURPOSE

We present two patients who developed neurogenic stuttering after long COVID-19 related to SARS-CoV-2 infection.

METHODS AND RESULTS

Both patients experienced both physical (e.g., fatigue) and cognitive difficulties, which led to impaired function of attention, lexical retrieval, and memory consolidation. Both patients had new-onset stuttering-like speech dysfluencies: Blocks and repetitions were especially evident at the initial part of words and sentences, sometimes accompanied by effortful and associated movements (e.g., facial grimaces and oro-facial movements). Neuropsychological evaluations confirmed the presence of difficulties in cognitive tasks, while neurophysiological evaluations (i.e., electroencephalography) suggested the presence of "slowed" patterns of brain activity. Neurogenic stuttering and cognitive difficulties were evident for 4-5 months after negativization of SARS-CoV-2 nasopharyngeal swab, with gradual improvement and near-to-complete recovery.

CONCLUSIONS

It is now evident that SARS-CoV-2 infection may significantly involve the central nervous system, also resulting in severe and long-term consequences, even if the precise mechanisms are still unknown. In the present report, long COVID-19 resulted in neurogenic stuttering, as the likely consequence of a "slowed" metabolism of (pre)frontal and sensorimotor brain regions (as suggested by the present and previous clinical evidence). As a consequence, the pathophysiological mechanisms related to the appearance of neurogenic stuttering have been hypothesized, which help to better understand the broader and possible neurological consequences of COVID-19.

Social anxiety disorder in adolescents who stutter: A risk for school refusal

BACKGROUND

Stuttering is a childhood-onset fluency disorder. Part of the counseling for middle and high school students with persistent stuttering is related to school refusal. Anxiety disorders are known to contribute to school refusal. However, it is not known whether social anxiety disorder (SAD) is a factor in school refusal among adolescents who stutter.

METHODS

In our first study, we examined the relationship between school refusal and SAD in 84 middle and high school students who stutter; 26% of the 84 students were in the school refusal group and the remaining 74% were in the school attendance group. The second study examined whether SAD was associated with 10 factors related to speech and stuttering frequency using the Japanese version of the Liebowitz Social Anxiety Scale for Children and Adolescents to determine the presence of SAD. Of the 84 students in the first study, 40 participated in the second study.

RESULTS

The school refusal group of adolescents who stutter had significantly higher rates of SAD than the school attendance group. Fifty percent of adolescents who stutter met the criteria for SAD. Moreover, adolescents who stutter with SAD had significantly higher scores on the items "When speaking in public, do you experience tremors in your limbs?" and "After you stutter, do you have negative thoughts about yourself?" than the adolescents who stutter without SAD.

CONCLUSIONS

When examining adolescents who stutter, checking for comorbid SAD may lead to better support. Moreover, noticing their repetitive negative thinking, nervousness, and trembling during speech may help to resolve SAD.

A systematic review on the role of language-related factors in the manifestation of stuttering in bilinguals

PURPOSE

Bilingual(s) who stutter (BWS) provide an opportunity to explore the link between stuttering and language. Unlike in monolinguals, stuttering in bilinguals could be influenced by both speaker-related language (e.gs. dominance & proficiency) and linguistic typology-related factors (e.g., structure of languages). However, the available literature is largely inconclusive on these factors. In this context, we systematically reviewed the literature to compile evidence on the influence of such factors on BWS.

METHOD

We followed the conventional systematic review process that included five databases. Further, the quality of the included articles was assessed using Newcastle-Ottawa Scale (NOS) for quality rating.

RESULT

Thirteen articles passed the selection criteria. Review of these articles revealed that language proficiency and dominance are the important factors that affect stuttering frequency in BWS. Though the linguistic typology is portrayed as a factor on the differential manifestation of dysfluencies in both languages of the BWS, the literature does not provide substantiating data for this. Further, the lack of uniformity in assessing and reporting language dominance and proficiency are the major drawbacks in the existing literature on stuttering in BWS.

CONCLUSION

This review identifies proficiency and dominance as the major factors that influence the stuttering frequency in BWS. Currently, the evidence for the influence of typological differences between languages of the BWS on stuttering largely remains whimsical. Future research shall employ the recommended tasks and metrics while assessing the dysfluencies in BWS so that findings across centres become comparable, which in turn, could yield valid inferences.

Bilinguals who stutter: A cognitive perspective

PURPOSE

Brain differences, both in structure and executive functioning, have been found in both developmental stuttering and bilingualism. However, the etiology of stuttering remains unknown. The early suggestion that stuttering is a result of brain dysfunction has since received support from various behavioral and neuroimaging studies that have revealed functional and structural brain changes in monolinguals who stutter (MWS). In addition, MWS appear to show deficits in executive control. However, there is a lack of data on bilinguals who stutter (BWS). This literature review is intended to provide an overview of both stuttering and bilingualism as well as synthesize areas of overlap among both lines of research and highlight knowledge gaps in the current literature.

METHODS

A systematic literature review on both stuttering and bilingualism studies was conducted, searching for articles containing "stuttering" and/or "bilingualism" and either "brain", "executive functions", "executive control", "motor control", "cognitive reserve", or "brain reserve" in the PubMed database. Additional studies were found by examining the reference list of studies that met the inclusion criteria.

RESULTS

A total of 148 references that met the criteria for inclusion in this paper were used in the review. A comparison of the impact of stuttering or bilingualism on the brain are discussed.

CONCLUSION

Previous research examining a potential bilingual advantage for BWS is mixed. However, if such an advantage does exist, it appears to offset potential deficits in executive functioning that may be associated with stuttering.

Neurogenic Stuttering: Etiology, Symptomatology, and Treatment

Background:

Neurogenic stuttering is a subtype of acquired stuttering, and it is characterized by disfluencies associated with acquired brain damage.

Objective:

To provide an insight into pathophysiology, symptomatology, differential diagnosis, assessment, and treatment of neurogenic stuttering through a critical review of the literature.

Methods:

Studies published during the past and recent years were searched and analyzed on neurogenic stuttering.

Results:

Neurogenic stuttering is a complex disorder. The pathophysiological mechanism of neurogenic stuttering is not yet fully understood. It appears with several neurological diseases and conditions, and the use of some drugs. Differential diagnosis of neurogenic and psychogenic stuttering is a challenge for clinicians. Treatment usually requires a joint effort from speech therapists and doctors, most often neurologists

Conclusion:

Although research on neurogenic stuttering can be found in the literature, the complexity of this disorder still requires detailed monitoring and studying to provide the best treatment for patients.

Bilingualism as a Purported Risk Factor for Stuttering: A Close Look at a Seminal Study (Travis et al., 1937)

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Psychological correlates of biological and non-biological explanations for stuttering

Purpose: This study examined whether people who stutter would associate biological and non-biological explanations of stuttering with the endorsement of stereotypes about people who stutter, prognostic expectations for the reduction of stuttering, feelings of guilt, self-blame, and shame about stuttering, and agency for speech modification.Method: This was a cross-sectional study including 372 adults who stutter. Participants completed a web survey with scales that measured their agreement with biological and non-biological models of stuttering; their endorsement of common stereotypes for people who stutter; prognostic expectations for reduced stuttering; feelings of guilt, self-blame, and shame about stuttering; and feelings of agency in their ability to modify their speech.Result: Biological explanations for stuttering were significantly correlated with reduced stereotype endorsement about people who stutter, lower prognostic expectations for reducing stuttering, and reduced feelings of guilt and self-blame regarding stuttering. Non-biological explanations for stuttering were significantly correlated with increased endorsement of negative stereotypes about people who stutter, increased prognostic expectations for reducing stuttering, and increased feelings of guilt, self-blame, and shame about stuttering.Conclusion: It is concluded that the implications of biological framing of stuttering among people who stutter are complex and should be well thought out by professionals. Explaining stuttering as biological, but responsive to personal and environmental influences, may lead to reduced guilt and self-blame, while at the same time fostering feelings of agency for speech modification.

Attention, Speech-Language Dissociations, and Stuttering Chronicity

The purpose of this study was to investigate the singular and joint contributions of speech-language dissociations and attention (i.e., distractibility and attention span) to stuttering chronicity. Method Participants, aged 3;0-4;11 (years;months) at an initial visit, were classified as persisting (n = 10; 9 boys), recovered (n = 32; 23 boys), and nonstuttering (n = 28; 19 boys) based on multiple speech and language evaluations spread across 2 years. The evaluations included assessments of articulation, receptive and expressive vocabulary, and omnibus receptive and expressive language. These measures were used to identify speech-language dissociations using a correlation-based statistical approach. Attentional characteristics, which included measures of distractibility and attention span, were based on parent report. Analyses investigated between-group differences related to dissociations and attentional characteristics as well as the relation between these indices. Results There were no significant between-group differences for the persisting and recovered groups on measures of speech-language dissociations; however, the recovered group was found to exhibit less optimal attention span than the persisting group. In addition, children with dissociations exhibited less optimal distractibility and attention spans at the final time point than children without dissociations. Conclusions Present results indicate that attention is related to both stuttering chronicity and the presence of speech-language dissociations; however, they do not support the notion that dissociations are associated with stuttering persistence. These results provide novel insights into the complex nature of the association between developmental stuttering, speech-language dissociations, and attention.

Limited Pre-Speech Auditory Modulation in Individuals Who Stutter: Data and Hypotheses

Purpose We review and interpret our recent series of studies investigating motor-to-auditory influences during speech movement planning in fluent speakers and speakers who stutter. In those studies, we recorded auditory evoked potentials in response to probe tones presented immediately prior to speaking or at the equivalent time in no-speaking control conditions. As a measure of pre-speech auditory modulation (PSAM), we calculated changes in auditory evoked potential amplitude in the speaking conditions relative to the no-speaking conditions. Whereas adults who do not stutter consistently showed PSAM, this phenomenon was greatly reduced or absent in adults who stutter. The same between-group difference was observed in conditions where participants expected to hear their prerecorded speech played back without actively producing it, suggesting that the speakers who stutter use inefficient forward modeling processes rather than inefficient motor command generation processes. Compared with fluent participants, adults who stutter showed both less PSAM and less auditory-motor adaptation when producing speech while exposed to formant-shifted auditory feedback. Across individual participants, however, PSAM and auditory-motor adaptation did not correlate in the typically fluent group, and they were negatively correlated in the stuttering group. Interestingly, speaking with a consistent 100-ms delay added to the auditory feedback signal-normalized PSAM in speakers who stutter, and there no longer was a between-group difference in this condition. Conclusions Combining our own data with human and animal neurophysiological evidence from other laboratories, we interpret the overall findings as suggesting that (a) speech movement planning modulates auditory processing in a manner that may optimize its tuning characteristics for monitoring feedback during speech production and, (b) in conditions with typical auditory feedback, adults who stutter do not appropriately modulate the auditory system prior to speech onset. Lack of modulation of speakers who stutter may lead to maladaptive feedback-driven movement corrections that manifest themselves as repetitive movements or postural fixations.

A Hispanic mother's beliefs about stuttering aetiology: A systemic functional linguistic analysis

The aim of this study was to identify the linguistic resources a Hispanic mother used to convey her beliefs about the aetiology of her adult son's stuttering. A qualitative research paradigm was adopted for data collection and analysis. An Ecuadorian mother and her adult son who stutters recorded a conversation in Spanish about the son's stuttering. Tools derived from systemic functional linguistic (SFL) theory were used to analyse conversation transcripts and to describe the word choices and sentence structures the mother used to talk about her son's stuttering. The mother deflected community-assigned blame for causing her son's stuttering by configuring her 'strong' temperament as a separate, uncontrollable entity. She structured the pervasiveness of stigma, lack of resources and misinformation within the community as causes for her inability to identify and seek help for her son's stuttering, which also served as a means for deflecting blame. SFL-based analyses were appropriate tools for the investigation of how a Hispanic mother construes her views, attitudes and experiences relative to her son's stuttering. Clinical implications of findings regarding parent education and the utility of SFL-based tools in the speech-language therapy setting are discussed.

Auditory-motor adaptation is reduced in adults who stutter but not in children who stutter

Previous studies have shown that adults who stutter produce smaller corrective motor responses to compensate for unexpected auditory perturbations in comparison to adults who do not stutter, suggesting that stuttering may be associated with deficits in integration of auditory feedback for online speech monitoring. In this study, we examined whether stuttering is also associated with deficiencies in integrating and using discrepancies between expected and received auditory feedback to adaptively update motor programs for accurate speech production. Using a sensorimotor adaptation paradigm, we measured adaptive speech responses to auditory formant frequency perturbations in adults and children who stutter and their matched nonstuttering controls. We found that the magnitude of the speech adaptive response for children who stutter did not differ from that of fluent children. However, the adaptation magnitude of adults who stutter in response to auditory perturbation was significantly smaller than the adaptation magnitude of adults who do not stutter. Together these results indicate that stuttering is associated with deficits in integrating discrepancies between predicted and received auditory feedback to calibrate the speech production system in adults but not children. This auditory-motor integration deficit thus appears to be a compensatory effect that develops over years of stuttering.

Neurogenic stuttering: a review of the literature

INTRODUCTION

Neurogenic stuttering is a disorder of neurologic origin in the rhythm of speech during which the patient knows exactly what he wants to say but is unable to because of an involuntary prolongation, cessation or repetition of a sound.

AIM

To assemble new insights regarding the epidemiology, pathophysiology, diagnosis, evaluation and treatment of neurogenic stuttering.

DEVELOPMENT

A review of all PubMed and Scopus published articles between January 2000 and September 2016 was performed. Thirty-three publications were analyzed. Neurogenic stuttering is a rare entity whose epidemiological incidence is yet not fully established. It is correlated with several neurological diseases and with several possible localizations within the nervous system. Notwithstanding the recent advances in the understanding of the underlying mechanism, it is not yet possible to establish a single pathophysiological mechanism of neurogenic stuttering. The differential diagnosis is complex and requires the detailed knowledge of other language disorders. The treatment is currently based on specific speech language therapy strategies.

CONCLUSION

Neurogenic stuttering is a complex disorder which is not fully understood. Additional studies might help to better explain the underlying pathophysiological mechanism and to open doors to novel therapeutic methods.

Developmental Stuttering in Children Who Are Hard of Hearing

Purpose

A number of studies with large sample sizes have reported lower prevalence of stuttering in children with significant hearing loss compared to children without hearing loss. This study used a parent questionnaire to investigate the characteristics of stuttering (e.g., incidence, prevalence, and age of onset) in children who are hard of hearing (CHH).

Method

Three hundred three parents of CHH who participated in the Outcomes of Children With Hearing Loss study (Moeller & Tomblin, 2015) were sent questionnaires asking about their child's history of stuttering.

Results

One hundred ninety-four parents of CHH responded to the survey. Thirty-three CHH were reported to have stuttered at one point in time (an incidence of 17.01%), and 10 children were still stuttering at the time of survey submission (a prevalence of 5.15%). Compared to estimates in the general population, this sample displayed a significantly higher incidence and prevalence. The age of onset, recovery rate, and other characteristics were similar to hearing children.

Conclusions

Based on this sample, mild to moderately severe hearing loss does not appear to be a protective factor for stuttering in the preschool years. In fact, the incidence and prevalence of stuttering may be higher in this population compared to the general population. Despite the significant speech and language needs that children with mild to moderately severe hearing loss may have, speech-language pathologists should appropriately prioritize stuttering treatment as they would in the hearing population.

Supplemental Material

https://doi.org/10.23641/asha.5397154.

Speech Timing Deficit of Stuttering: Evidence from Contingent Negative Variations

The aim of the present study was to investigate the speech preparation processes of adults who stutter (AWS). Fifteen AWS and fifteen adults with fluent speech (AFS) participated in the experiment. The event-related potentials (ERPs) were recorded in a foreperiod paradigm. The warning signal (S1) was a color square, and the following imperative stimulus (S2) was either a white square (the Go signal that required participants to name the color of S1) or a white dot (the NoGo signal that prevents participants from speaking). Three differences were found between AWS and AFS. First, the mean amplitude of the ERP component parietal positivity elicited by S1 (S1-P3) was smaller in AWS than in AFS, which implies that AWS may have deficits in investing working memory on phonological programming. Second, the topographic shift from the early phase to the late phase of contingent negative variation occurred earlier for AWS than for AFS, thus suggesting that the motor preparation process is promoted in AWS. Third, the NoGo effect in the ERP component parietal positivity elicited by S2 (S2-P3) was larger for AFS than for AWS, indicating that AWS have difficulties in inhibiting a planned speech response. These results provide a full picture of the speech preparation and response inhibition processes of AWS. The relationship among these three findings is discussed. However, as stuttering was not manipulated in this study, it is still unclear whether the effects are the causes or the results of stuttering. Further studies are suggested to explore the relationship between stuttering and the effects found in the present study.

The impact of causal attribution on stigmatizing attitudes toward a person who stutters

PURPOSE

This study investigated the impact of providing low control (biological) and high control (psychobehavioral) causal explanations for stuttering on a variety of stigma related variables including blame, anger, social distance, stereotypes, dislike, sympathy, willingness to help, and perceptions of potential for recovery for a hypothetical person who stutters.

METHOD

One hundred and sixty-five university students read one of three vignettes describing a person who stutters with different descriptions about the cause of stuttering (low control, high control, and a control group in which no explanation was given) and answered a series of self-report measures assessing stigmatizing attitudes and perceived potential for recovery.

RESULTS

The controllable explanation for stuttering led to more blame compared to the uncontrollable explanation and no explanation. The controllable explanation resulted in higher levels of anger and stereotypes compared to no explanation. There were no significant differences between uncontrollable explanations and no explanation on any of the stigma related variables of interest. Uncontrollable explanations increased prognostic pessimism compared to controllable explanations. Self-reported familiarity and closeness with people who stutter was significantly related to more positive attitudes toward a hypothetical person who stutters.

CONCLUSIONS

Reducing the belief that stuttering is ultimately caused by psychobehavioral factors will reduce blame toward people who stutter. However, providing biological explanations for stuttering is not effective for reducing stigma compared to no explanation at all, and could increase prognostic pessimism. Biological explanations for stuttering should be provided to inform clients and society about current research findings, however this information must be given carefully and be balanced with evidence that people who stutter can make great progress with appropriate, personalized therapy that addresses the multidimensionality of the disorder.

LEARNING OUTCOMES

As a result of reading this paper, readers should be able to: (1) describe how causal attributions impact attitudes toward individuals with disabilities (2) summarize the effects of providing a biological explanation for stuttering on stigmatizing attitudes toward a person who stutters (3) summarize the effects of providing a psychobehavioral explanation for stuttering on stigmatizing attitudes toward a person who stutters, (4) discuss how familiarity and closeness toward people who stutter relates to stigmatizing attitudes toward a person who stutters.

Understanding perceptions of stuttering among school-based speech-language pathologists: an application of attribution theory

INTRODUCTION

The purpose of this study was to investigate whether attribution theory could explain speech-language pathologists (SLPs) perceptions of children with communication disorders such as stuttering. Specifically, it was determined whether perceptions of onset and offset controllability, as well as biological and non-biological attributions for communication disorders were related to willingness to help, sympathy, and anger toward children with these disorders. It was also of interest to determine if blame for stuttering was related to perceived controllability of stuttering and negative attitudes toward people who stutter (PWS).

METHOD

A survey was developed to measure perceived onset and offset controllability, biological and non-biological attributions, willingness to help, sympathy, and anger toward middle school children with developmental stuttering, functional articulation disorders, and cerebral palsy. In addition, a scale was developed to measure blame and negative attitudes toward PWS in general. Surveys were mailed to 1000 school-based SLPs. Data from 330 participants were analyzed.

RESULTS

Supporting the hypotheses of attribution theory, higher perceived onset and offset controllability of the disorder was linked to less willingness to help, lower sympathy, and more anger across conditions. Increased biological attributions were associated with more reported sympathy. Increased blame for stuttering was linked to higher perceived controllability of stuttering, more dislike of PWS, and more agreement with negative stereotypes about PWS.

CONCLUSIONS

Educating SLPs about the variable loss of control inherent in stuttering could improve attitudes and increase understanding of PWS. Reductions in blame may facilitate feelings of sympathy and empathy for PWS and reduce environmental barriers for clients. Learning outcomes Readers should be able to: (1) identify the main principles of Weiner's attribution theory (2) identify common negative perceptions of people who stutter (3) describe how disorders of stuttering, articulation disorders, and cerebral palsy are differentiated in terms of perceived onset and offset controllability, and biological and non-biological attributions (4) describe relationships between perceived onset and offset controllability of disorders and sympathy, anger, and willingness to help.

Stuttering in relation to anxiety, temperament, and personality: review and analysis with focus on causality

Anxiety and emotional reactions have a central role in many theories of stuttering, for example that persons who stutter would tend to have an emotionally sensitive temperament. The possible relation between stuttering and certain traits of temperament or personality were reviewed and analyzed, with focus on temporal relations (i.e., what comes first). It was consistently found that preschool children who stutter (as a group) do not show any tendencies toward elevated temperamental traits of shyness or social anxiety compared with children who do not stutter. Significant group differences were, however, repeatedly reported for traits associated with inattention and hyperactivity/impulsivity, which is likely to reflect a subgroup of children who stutter. Available data is not consistent with the proposal that the risk for persistent stuttering is increased by an emotionally reactive temperament in children who stutter. Speech-related social anxiety develops in many cases of stuttering, before adulthood. Reduction of social anxiety in adults who stutter does not in itself appear to result in significant improvement of speech fluency. Studies have not revealed any relation between the severity of the motor symptoms of stuttering and temperamental traits. It is proposed that situational variability of stuttering, related to social complexity, is an effect of interference from social cognition and not directly from the emotions of social anxiety. In summary, the studies in this review provide strong evidence that persons who stutter are not characterized by constitutional traits of anxiety or similar constructs.

EDUCATIONAL OBJECTIVES

This paper provides a review and analysis of studies of anxiety, temperament, and personality, organized with the objective to clarify cause and effect relations. Readers will be able to (a) understand the importance of effect size and distribution of data for interpretation of group differences; (b) understand the role of temporal relations for interpretation of cause and effect; (c) discuss the results of studies of anxiety, temperament and personality in relation to stuttering; and (d) discuss situational variations of stuttering and the possible role of social cognition.

Prevalence of risk factors for stuttering among boys: analytical cross-sectional study

CONTEXT AND OBJECTIVE

There have been few studies on the risk factors for subgroups of stuttering. The aim of this study was to characterize the risk factors for developmental familial stuttering among boys who stutter and who do not stutter, such as disfluency types, associated quality and communication factors, emotional and physical stress, familial attitudes and personal reactions.

DESIGN AND SETTING

Analytical cross-sectional study with a control group, performed at the Fluency Studies Laboratory of the Department of Speech and Hearing Disorders of a public university.

METHODS

The parents of 40 age-matched stuttering and non-stuttering boys took part in this study. The participants were divided into two groups: stuttering children (SC) and non-stuttering children (NSC), with ages between 6 years 0 months and 11 years 11 months. Initially, all of the participants underwent a fluency assessment and then data were gathered using the Protocol for the Risk of Developmental Stuttering.

RESULTS

There were no differences in the physical stress distribution factors and personal reactions between the groups. Inappropriate familial attitudes were presented by 95% of the SC and 30% of the NSC. Four risk factors analyzed were not shown by the NSC, namely stuttering-like disfluency, quality factors, physical stress and emotional stresses.

CONCLUSIONS

The findings suggest that the presence of stuttering-like disfluency, associated quality and communication factors, emotional stress and inappropriate family attitudes are important risk factors for familial developmental stuttering among boys.

Emotional reactivity and regulation associated with fluent and stuttered utterances of preschool-age children who stutter

PURPOSE

The purpose of this study was to assess the relation between emotional reactivity and regulation associated with fluent and stuttered utterances of preschool-age children who stutter (CWS) and those who do not (CWNS).

PARTICIPANTS

Participants were eight 3 to 6-year old CWS and eight CWNS of comparable age and gender.

METHODS

Participants were exposed to three emotion-inducing overheard conversations--neutral, angry and happy--and produced a narrative following each overheard conversation. From audio-video recordings of these narratives, coded behavioral analysis of participants' negative and positive affect and emotion regulation associated with stuttered and fluent utterances was conducted.

RESULTS

Results indicated that CWS were significantly more likely to exhibit emotion regulation attempts prior to and during their fluent utterances following the happy as compared to the negative condition, whereas CWNS displayed the opposite pattern. Within-group assessment indicated that CWS were significantly more likely to display negative emotion prior to and during their stuttered than fluent utterances, particularly following the positive overheard conversation.

CONCLUSIONS

After exposure to emotional-inducing overheard conversations, changes in preschool-age CWS's emotion and emotion regulatory attempts were associated with the fluency of their utterances.

LEARNING OUTCOMES

After reading this article, the reader will be able to: (1) describe various measures of emotional reactivity and regulation, including parent-based reports and behavioral coding, and how they may contribute to childhood stuttering; (2) explain emotional differences between the stuttered and fluent utterances of CWS and CWNS; and (3) discuss how emotions may contribute to CWS' instances of stuttering.

Socioeconomic status, parental education, vocabulary and language skills of children who stutter

PURPOSE

The purpose of this project was to investigate the possible relation between standardized measures of vocabulary/language, mother and father education, and a composite measure of socioeconomic status (SES) for children who do not stutter (CWNS) and children who stutter (CWS).

METHODS

Participants were 138 CWNS and 159 CWS between the ages of 2;6 and 6;3 and their families. The Hollingshead Four Factor Index of Social Position (i.e., Family SES) was used to calculate SES based on a composite score consisting of weighted values for paternal and maternal education and occupation. Statistical regression analyses were conducted to investigate the relation between parental education and language and vocabulary scores for both the CWNS and CWS. Correlations were calculated between parent education, Family SES, and stuttering severity (e.g., SSI-3 score, % words stuttered).

RESULTS

Results indicated that maternal education contributed the greatest amount of variance in vocabulary and language scores for the CWNS and for participants from both groups whose Family SES was in the lowest quartile of the distribution. However, paternal education generally contributed the greatest amount of variance in vocabulary and language scores for the CWS. Higher levels of maternal education were associated with more severe stuttering in the CWS.

CONCLUSION

Results are generally consistent with existing literature on normal language development that indicates maternal education is a robust predictor of the vocabulary and language skills of preschool children. Thus, both father and mothers' education may impact the association between vocabulary/language skills and childhood stuttering, leading investigators who empirically study this association to possibly re-assess their participant selection (e.g., a priori control of parental education) and/or data analyses (e.g., post hoc covariation of parental education).

LEARNING OUTCOMES

The reader will be able to: (a) describe the influence of socioeconomic status on the development of vocabulary and language for children who do and do not stutter; (b) discuss the contribution of maternal education on vocabulary and language development; (c) describe possible reasons why paternal education contributes in unique ways to the vocabulary and language development of children who stutter as well as stuttering severity; and (d) explain possible reasons why socioeconomic status is an important variable for describing language related findings in young children.

Logistic regression for risk factor modelling in stuttering research

OBJECTIVES

To outline the uses of logistic regression and other statistical methods for risk factor analysis in the context of research on stuttering.

DESIGN

The principles underlying the application of a logistic regression are illustrated, and the types of questions to which such a technique has been applied in the stuttering field are outlined. The assumptions and limitations of the technique are discussed with respect to existing stuttering research, and with respect to formulating appropriate research strategies to accommodate these considerations. Finally, some alternatives to the approach are briefly discussed.

RESULTS

The way the statistical procedures are employed are demonstrated with some hypothetical data.

CONCLUSION

Research into several practical issues concerning stuttering could benefit if risk factor modelling were used. Important examples are early diagnosis, prognosis (whether a child will recover or persist) and assessment of treatment outcome.

EDUCATIONAL OBJECTIVES

After reading this article you will: (a) Summarize the situations in which logistic regression can be applied to a range of issues about stuttering; (b) Follow the steps in performing a logistic regression analysis; (c) Describe the assumptions of the logistic regression technique and the precautions that need to be checked when it is employed; (d) Be able to summarize its advantages over other techniques like estimation of group differences and simple regression.

Risk factors and stuttering: evaluating the evidence for clinicians

This paper summarizes and discusses some of the key issues raised in the other four manuscripts in this special edition of Journal of Fluency Disorders. All the four pieces examine risk factors in developmental stuttering from different perspectives and all provide stand-alone contributions to knowledge on the subject. Thus, rather than review, the focus of the present paper is to highlight those matters, which, from a clinical perspective might be seen as either (a) of the greatest contention, (b) of particular relevance to clinicians, or (c) requiring greater emphasis in future research, on the basis of the conclusions from the authors involved.

EDUCATIONAL OBJECTIVES

This paper provides an overview of points of particular clinical interest arising from the four contributions to this special edition. Readers will be able to (a) understand arguments for and against whole word repetitions being included as moments of stuttering in the SSI-3 assessment, (b) understand arguments relating to psychological components in early onset stuttering, (c) understand some of the complexities in interpreting data pertaining to recovery from stuttering, (d) understand where future efforts in research into risk of stuttering should be placed.

Attitudes of Turkish speech and language therapists toward stuttering

PURPOSE

The study sought to identify clinical beliefs and attitudes of speech and language therapists (SLTs) in Turkey and to compare them to previous research on SLTs in the USA and UK.

METHOD

The Clinician Attitudes Toward Stuttering (CATS) inventory was administered by mail to nearly all-practicing SLTs in Turkey (n=61).

RESULTS

Turkish SLTs, whose caseloads contained a substantial number of people who stutter, agreed with CATS items suggesting psychological causes and problems for those who stutter. They strongly believed therapy should focus on parent counseling for preschoolers who stutter as well as adolescents. They were not optimistic about carrying out stuttering therapy nor about the likelihood that children who stutter could be effectively treated.

CONCLUSION

Attitudes toward stuttering by clinicians who treat them are important considerations in the conduct and outcomes of stuttering therapy. Additionally, SLTs working with stuttering clients should benefit from professional views and clinical experiences of their colleagues from surveys such as this one.

EDUCATIONAL OBJECTIVES

The reader will be able to describe: (a) the components of the CATS, (b) common themes in Turkish speech and language therapists' attitudes toward stuttering, (c) differences between the attitudes of speech and language therapists from Turkey versus the United States and the United Kingdom.

Epidemiology of stuttering: 21st century advances

Epidemiological advances in stuttering during the current century are reviewed within the perspectives of past knowledge. The review is organized in six sections: (a) onset, (b) incidence, (c) prevalence, (d) developmental paths, (e) genetics and (f) subtypes. It is concluded that: (1) most of the risk for stuttering onset is over by age 5, earlier than has been previously thought, with a male-to-female ratio near onset smaller than what has been thought, (2) there are indications that the lifespan incidence in the general population may be higher than the 5% commonly cited in past work, (3) the average prevalence over the lifespan may be lower than the commonly held 1%, (4) the effects of race, ethnicity, culture, bilingualism, and socioeconomic status on the incidence/prevalence of stuttering remain uncertain, (5) longitudinal, as well as incidence and prevalence studies support high levels of natural recovery from stuttering, (6) advances in biological genetic research have brought within reach the identification of candidate genes that contribute to stuttering in the population at large, (7) subtype-differentiation has attracted growing interest, with most of the accumulated evidence supporting a distinction between persistent and recovered subtypes.

EDUCATIONAL OBJECTIVES

Readers will be exposed to a summary presentation of the most recent data concerning basic epidemiological factors in stuttering. Most of these factors also pertain to children's risks for experiencing stuttering onset, as well as risks for persistency. The article also aims to increase awareness of the implications of the information to research, and professional preparation that meets the epidemiology of the disorder.

Revisiting Bloodstein's Anticipatory Struggle Hypothesis from a psycholinguistic perspective: a Variable Release Threshold hypothesis of stuttering

This paper reviews Bloodstein's (1975) Anticipatory Struggle Hypothesis of stuttering, identifies its weaknesses, and proposes modifications to bring it into line with recent advances in psycholinguistic theory. The review concludes that the Anticipatory Struggle Hypothesis provides a plausible explanation for the variation in the severity of stuttered disfluencies across speaking situations and conversation partners. However, it fails to explain the forms that stuttered disfluencies characteristically take or the subjective experience of loss of control that accompanies them. The paper then describes how the forms and subjective experiences of persistent stuttering can be accounted for by a threshold-based regulatory mechanism of the kind described in Howell's (2003) revision of the EXPLAN hypothesis. It then proposes that shortcomings of both the Anticipatory Struggle and EXPLAN hypotheses can be addressed by combining them together to create a 'Variable Release Threshold' hypothesis whereby the anticipation of upcoming difficulty leads to the setting of an excessively high threshold for the release of speech plans for motor execution. The paper also reconsiders the possibility that two stuttering subtypes exist: one related to formulation difficulty and other to difficulty initiating motor execution. It concludes that research findings that relate to the one may not necessarily apply to the other.

LEARNING OUTCOMES

After reading this article, the reader will be able to: (1) summarize the key strengths and weaknesses of Bloodstein's Anticipatory Struggle Hypothesis; (2) describe two hypothesized mechanisms behind the production of stuttered disfluencies (tension and fragmentation & release threshold mechanisms); and (3) discuss why the notion of anticipation is relevant to current hypotheses of stuttering.

Theory and therapy in stuttering: a complex relationship

There are many treatments currently available for stuttering, for both children and adults. These range from direct interventions intended to reduce the severity and/or frequency of the speech behaviors of stuttering, to those intended to alleviate the anxiety and other mental health issues that can accompany the disorder. However, as there are little supporting data for many of these treatments, there is little consensus about which to use. Another way to evaluate stuttering treatments is to explore the extent to which they address the cause of the disorder. However, the cause of stuttering is not yet known. In this theoretical paper, a 3-factor causal model is presented, to which the mechanisms thought to be driving different treatments are then aligned. The model is innovative, in that it attempts to explain moments of stuttering. It is argued that all causal factors must be operating at each moment of stuttering. The model is intended as a new way of looking at cause, and how treatments may address cause. It is hoped this will stimulate discussion and lead to further lines of inquiry.

EDUCATIONAL OBJECTIVES

The reader will be able to: (a) describe the P&A 3-factor causal model of moments of stuttering; (b) state how indirect direct stuttering treatments relate to cause, according to the P&A model; (c) describe how direct stuttering treatments relate to cause, according to the P&A model; (d) state the purpose of cognitive behavior therapy; and (e) describe at least one suggestion for further research arising from the P&A model.

Genetic and environmental effects on stuttering: a twin study from Finland

The present study explored the prevalence of self-reported stuttering in a Finnish twin population and examined the extent to which the variance in liability to stuttering was attributable to genetic and environmental effects. We analyzed data of 1728 Finnish twins, born between 1961 and 1989. The participants were asked to complete a questionnaire on speech, language, and voice. In two of the questions they were asked to report the occurrence of childhood and present stuttering of their own and that of their sibling. According to the results, 2.3% (52) of the participants were reported to have stuttered as children and 28.8% of them (15) were reported to continue to stutter in adulthood. There was no significant gender difference in the prevalence of stuttering in either childhood or adulthood. For childhood stuttering, the tetrachoric correlation was higher for monozygotic pairs (r=.74) than for dizygotic pairs (r=.27). By means of structural equation modeling it was found that 82% of the variance in liability to childhood stuttering was attributable to additive genetic effects, with the remaining 18% due to non-shared environmental effects. In conclusion, the results of the present study confirm findings from prior studies and support a strong genetic and only a moderate non-shared environmental effect on stuttering. Potential small differences in the prevalence of stuttering in different populations are suggested by our data.

EDUCATIONAL OBJECTIVES

The reader will be able to recognize the contribution of genetic and environmental effects on stuttering.

Early stuttering, temperament and anxiety: two hypotheses

PURPOSE

The topic of temperament and early stuttering and the extent to which it involves anxiety is theoretically and clinically relevant. The topic can contribute to theory development and clinical practices with early stuttering.

METHOD

We present a review of the empirical literature for this area with a view to determining which of two hypotheses might be true. The first is that, for the population of those who stutter, unusual temperament is a causal factor for the development of the disorder and its later association with anxiety. The second hypothesis is that for the population of those who stutter the developmental manifestation of anxiety is an effect of stuttering. Both hypotheses attempt to account for the well-known association of anxiety with chronic stuttering.

RESULTS

A firm conclusion about the matter would be premature at present because the literature involved is limited and contains some inconsistencies. We suggest some quantitative and qualitative directions for future research. We argue also that the only way to resolve the matter is with longitudinal studies of cohorts ascertained prior to stuttering onset.

CONCLUSION

Conclusive findings about the matter can only emerge when research extends beyond its modest scope of 10 interpretable publications.

EDUCATIONAL OBJECTIVES

The reader will be able to: (a) describe temperament and the role it plays during anxiety development, (b) explain two alternative hypotheses which implicate temperament in early childhood stuttering; (c) describe current knowledge regarding temperament similarities and differences between stuttering and control children, and (d) discuss the theoretical and clinical implications of understand the relationship between temperament, anxiety and early stuttering.

The influence of anticipation of word misrecognition on the likelihood of stuttering

This study investigates whether the experience of stuttering can result from the speaker's anticipation of his words being misrecognized. Twelve adults who stutter (AWS) repeated single words into what appeared to be an automatic speech-recognition system. Following each iteration of each word, participants provided a self-rating of whether they stuttered on it and the computer then provided feedback implying its correct or incorrect recognition of it. Each word was repeated four times. Unbeknown to participants, 'Correct' and 'Incorrect' recognition of words by the system was pre-determined and bore no relation to the actual quality of participants' iterations of those words. For words uttered in the 'Correct recognition' condition, the likelihood of AWS self-reporting stuttering on a word diminished across iterations, whereas for words in the 'Incorrect recognition' condition it remained static. On the basis of the findings it is argued that: (a) in AWS, the anticipation that a word will be misrecognized increases the relative likelihood of stuttering on that word in the future; and (b) this effect is independent of the degree of difficulty inherent in the formulation and motor execution of the word itself, although it may interact with it. Mechanisms that can account for these findings and yet are also congruent with the wider range of evidence from psycholinguistic and speech motor control domains are discussed. It is concluded that stuttered disfluencies may best be explained as resulting from the inappropriate functioning of covert repair and/or variable release threshold mechanisms in response to the anticipation of communication failure.

LEARNING OUTCOMES

This article informs readers about two different theoretical approaches to explaining developmental stuttering: (1) stuttering as an adaptation response to an underlying impairment; and (2) stuttering as an anticipatory struggle response. It describes how these approaches account for different symptoms of the disorder, and proposes that both theoretical approaches are needed in order to fully account for the range of symptoms and experimental findings associated with stuttering.

Parenting styles and attachment in school-aged children who stutter

Parental input has been described as influential in early childhood stuttering yet the exact nature of this influence remains equivocal. The present study aimed to examine whether quantitative measures of parenting styles, parent and peer attachment patterns, and parent- and self-reported child behaviour could differentiate between school-aged children who stutter (CWS) (n=10) and their fluent peers (n=10). In addition, qualitative individual semi-structured interviews with all CWS were conducted to gain insight into their life experiences and reflections in relation to stuttering. The interviews were classified into ancillary themes of school, peers and parents. Quantitative findings revealed that CWS perceived their parents with significantly lower attachment, particularly in relation to trust, and parents of CWS perceived their children with significantly higher maladjustments than fluent counterparts. Qualitative themes emerged pertaining to attitudes, perceptions and relationships with teachers, peers and parents, with consistent experiences of teasing and bullying reported as a consequence of the stutter. The majority of participants recounted frustration with the nature in which their parents attempted to remediate their stuttering. Collectively, these findings highlight imperative management considerations for school-aged CWS and their parents. The usefulness of quantitative and qualitative research paradigms is also emphasised.

LEARNING OUTCOMES

The reader will be able to: (1) identify themes associated with the impact a childhood stutter has on parent and peer relationships; (2) identify how the quality of the parent child relationship is influenced by parenting styles and attachment; and (3) discuss the clinical implications of the results for children who stutter and their families.

A one year prospective study of neurogenic stuttering following stroke: incidence and co-occurring disorders

In this prospective study, data on incidence, stuttering characteristics, co-occurring speech disorders, and recovery of neurogenic stuttering in a large sample of stroke participants were assessed. Following stroke onset, 17 of 319 participants (5.3%; 95% CI, 3.2-8.3) met the criteria for neurogenic stuttering. Stuttering persisted in at least 2.5% (95% CI, 1.1-4.7) for more than six months following the stroke. Participants with comorbid aphasia presented with a significantly higher frequency of stuttering compared to the group without aphasia (U=13.00, p((1-tailed))=.02) but no difference was found for participants with co-occurring dysarthria and/or cognitive problems. Participants with neurogenic stuttering did not differ from those without stuttering in terms of stroke risk factors or stroke etiologic subtypes. Although the incidence of stuttering following stroke is lower than that for aphasia or dysarthria, these results show that clinicians should take neurogenic stuttering into account when assessing stroke participants' speech and language.

LEARNING OUTCOMES

: Readers will be able to: (1) understand the need for systematic, prospective studies in neurogenic stuttering; (2) know the incidence and prevalence of neurogenic stuttering following stroke; and (3) know how neurogenic stuttering co-occurs with other speech-language disorders following stroke.

Developmental and persistent developmental stuttering: an overview for primary care physicians

Stuttering is a speech disorder characterized by a disruption in the fluency, timing, and rhythm of normal speech. It affects approximately 5% of children at some point in their lives. Although dysfluency often resolves before adulthood, it may cause periods of extreme anxiety for patients, especially those who continue to stutter in adolescence and adulthood. Although these patients are unlikely to stop stuttering, treatment options are available to reduce anxiety and therefore the severity of symptoms. In the present review article, the authors discuss the pathophysiology, diagnosis, and management of developmental stuttering in children and adults.

[Aquired stuttering in addition to a recurrence of developmental stuttering caused by brain tumor in the corpus callosum]

We reported a 66-year-old right-handed man, in whom developmental stuttering had almost been cured previously, who suffered a brain tumor. He developed not only left hemiparesis but also speech dysfluency such as acquired stuttering and aphasia. MRI showed a brain tumor in the body of the corpus callosum. The main feature of his stuttering was repetition of syllables. His stuttering was associated without secondary phenomena such as tongue clicking. His stuttering demonstrated no adaptation benefit and no consistency effect. These results suggest that the stuttering in this patient might have characteristics of both developmental and acquired stuttering, which in turn may suggest that after brain tumor, acquired stuttering occurs in addition to a recurrence of developmental stuttering.

Investigating the inner speech of people who stutter: evidence for (and against) the covert repair hypothesis

In their Covert Repair Hypothesis, Postma and Kolk (1993) suggest that people who stutter make greater numbers of phonological encoding errors, which are detected during the monitoring of inner speech and repaired, with stuttering-like disfluencies as a consequence. Here, we report an experiment that documents the frequency with which such errors are made. Thirty-two people who stutter (PWS) and thirty-two normally fluent controls, matched for age, gender and education, recited tonguetwisters and self-reported any errors they perceived themselves to have made. In 50% of trials the tonguetwisters were recited silently and errors reported were those detected in inner speech. Compared to controls, PWS produced significantly more word-onset and word-order errors. Crucially, this difference was found in inner as well as in overt speech. Comparison of experimenter ratings and participants' own self-ratings of their overt speech revealed similar levels of accuracy across the two groups, ruling out a suggestion that PWS were simply more sensitive to the errors they made. However, the frequency of participants' inner-speech errors was not correlated to their SSI4 scores, nor to two other measures of stuttering severity. Our findings support Postma and Kolk's contention that, when speech rate is held constant, PWS make, and therefore detect, more errors of phonological encoding. They do not, however, support the hypothesis that stuttering-like disfluencies in everyday speech stem from covert repairs of errors of phonological encoding.

LEARNING OUTCOMES

Readers will learn about three current psycholinguistic theories of stuttering, and how speech-errors elicited during tonguetwister recitation can be used to explore the controversies that exist surrounding: (a) Whether or not people who stutter are more prone to making language production errors; and (b) The extent to which stuttering-like disfluencies stem from covert repairs of language-production errors.

Analysis of five cases with neurogenic stuttering following brain injury in the basal ganglia

This study examined stuttering patterns in five patients with basal ganglia injury. None of the patients had a history of developmental stuttering. Four patients were right-handed; one patient was ambidextrous. Stuttering tests administered to patients assessed sentence repetition, reading aloud, explanations of a comic strip, and conversation. Accessory behaviors such as facial grimaces, associated movements of the limbs, and avoidance behaviors were observed. The results of this study differ from those of previous studies of neurogenic stuttering in several respects: (1) blocks were frequently observed. (2) Adaptation was observed. (3) Almost all stuttering occurred at the initiation of words. (4) Across patients, stuttering frequency did not vary in a consistent manner with speaking task. New speech characteristics for neurogenic stuttering without aphasia following injury to the basal ganglia are described.

EDUCATIONAL OBJECTIVES

After reading this text, the reader will be able to: (1) provide characteristics of neurogenic stuttering after the basal ganglia in patients without aphasia; (2) discuss the difference of the features and characteristics of stuttering between previously reported patients and present patients.

Temperament dimensions in stuttering and typically developing children

PURPOSE

The purpose of this study was to determine whether children who stutter (CWS) and typically developing children (TDC) differ from each other on composite temperament factors or on individual temperament scales.

METHODS

Participants consisted of 116 age and gender-matched CWS and TDC (3.04-8.11). Temperament was assessed with a Dutch version of the Children's Behavior Questionnaire (CBQ-D; Van den Bergh and Ackx, 2003), a caregiver rating scale.

RESULTS

Results indicated significant differences between participant groups on the composite temperament factors of Negative Affectivity, and Effortful Control. Analysis of the individual temperament scales showed that CWS, compared to the TDC, scored significantly lower on the scales of 'Inhibitory Control' and 'Attentional Shifting' and higher on the scales of 'Anger/Frustration', 'Approach' and 'Motor Activation'. Stuttering severity and months of therapy were not associated with either of the temperament dimensions.

CONCLUSIONS

The present study provides data that support the hypothesis that CWS and TDC differ on both composite temperament factors and temperament scales. The findings were interpreted within existing frameworks of temperament development, as well as with regard to previous studies of temperament in CWS.

EDUCATIONAL OBJECTIVES

After reading this article, the reader will be able to: (1) describe the concept of temperament, including Rothbart's temperamental model, and its functional significance; (2) explain the CBQ-based (Children's Behavior Questionnaire) temperamental differences between CWS and CWNS; and (3) explain possible pathways for interaction between temperament and the development of stuttering.

Overreliance on auditory feedback may lead to sound/syllable repetitions: simulations of stuttering and fluency-inducing conditions with a neural model of speech production

This paper investigates the hypothesis that stuttering may result in part from impaired readout of feedforward control of speech, which forces persons who stutter (PWS) to produce speech with a motor strategy that is weighted too much toward auditory feedback control. Over-reliance on feedback control leads to production errors which if they grow large enough, can cause the motor system to "reset" and repeat the current syllable. This hypothesis is investigated using computer simulations of a "neurally impaired" version of the DIVA model, a neural network model of speech acquisition and production. The model's outputs are compared to published acoustic data from PWS' fluent speech, and to combined acoustic and articulatory movement data collected from the dysfluent speech of one PWS. The simulations mimic the errors observed in the PWS subject's speech, as well as the repairs of these errors. Additional simulations were able to account for enhancements of fluency gained by slowed/prolonged speech and masking noise. Together these results support the hypothesis that many dysfluencies in stuttering are due to a bias away from feedforward control and toward feedback control.

EDUCATIONAL OBJECTIVES

The reader will be able to (a) describe the contribution of auditory feedback control and feedforward control to normal and stuttered speech production, (b) summarize the neural modeling approach to speech production and its application to stuttering, and (c) explain how the DIVA model accounts for enhancements of fluency gained by slowed/prolonged speech and masking noise.

Evidence that a motor timing deficit is a factor in the development of stuttering

PURPOSE

To determine whether young children who stutter have a basic motor timing and/or a coordination deficit.

METHOD

Between-hands coordination and variability of rhythmic motor timing were assessed in 17 children who stutter (4-6 years of age) and 13 age-matched controls. Children clapped in rhythm with a metronome with a 600-ms interbeat interval and then attempted to continue to match this target rate for 32 unpaced claps.

RESULTS

Children who stutter did not significantly differ from children who were typically developing on mean clapping rate or number of usable trials produced; however, they produced remarkably higher variability levels of interclap interval. Of particular interest was the bimodal distribution of the stuttering children on clapping variability. One subgroup of children who stutter clustered within the normal range, but 60% of the children who stutter exhibited timing variability that was greater than the poorest performing nonstuttering child. Children who stutter were not more variable in measures of coordination between the 2 hands (mean and median phase difference between hands).

CONCLUSION

We infer that there is a subgroup of young stuttering children who exhibit a nonspeech motor timing deficit, and we discuss this result as it pertains to recovery or persistence of stuttering.

Relief of acquired stuttering associated with Parkinson's disease by unilateral left subthalamic brain stimulation

PURPOSE

In this article, the authors report a case of acquired stuttering associated with Parkinson's disease (PD) that was responsive to unilateral subthalamic nucleus deep-brain stimulation (STN DBS) in the language-dominant hemisphere.

METHOD

A single-subject, masked, multiple baseline design was used to evaluate the effects of unilateral left STN DBS on stuttering associated with PD. The patient underwent 3 formal speech assessments of spontaneous speech and the reading of passages with DBS off and on. Speech samples were videotaped and placed in random order, and 2 independent speech-language pathologists calculated the percentage of stuttered syllables and classified individual stuttering events.

RESULTS

Stuttering improved significantly in the DBS-on condition. In total, 10% of syllables were affected by stuttering events with DBS off, and less than 1% of syllables were affected by stuttering events with DBS on (n = 2,281 syllables, p < .00001, in a chi(2) test). The effect of unilateral STN DBS on stuttering was relatively independent of whether the patient was on or off dopaminergic medications.

CONCLUSION

This article emphasizes the important role of the subthalamic region in the motor control of speech and language.

Effects of perceived causality on perceptions of persons who stutter

This study examined the effects of the perceived cause of stuttering on perceptions of persons who stutter (PWS) using a 7-item social distance scale, a 25-item adjective pair scale and a 2-item visual analogue scale. Two hundred and four university students rated vignettes which varied on describing a PWS with different causalities for stuttering (psychological, genetic, or unknown). Ratings differed significantly according to assigned causality. The vignette with the stuttering due to psychological causes was rated more negatively on 14 adjective pairs and the Social Distance Scale Index when compared to the ratings of vignettes with stuttering caused by either genetic or unknown causes. Interestingly, there were no significant differences between ratings of the vignettes attributing stuttering to either genetic or unknown causes. Neither familiarity with PWS nor the perceived curability of stuttering had any significant association to the ratings. Implications of findings regarding negative stereotypes, stigmatization and perceived causality for PWS are discussed.

EDUCATIONAL OBJECTIVES

Readers will be able to describe and explain: (1) research regarding negative stereotypes and stigma associated with stuttering, (2) research about attribution theory and stigma, (3) two methods used to evaluate stereotypes and stigma in adults, and (4) the negative effects on ratings of PWS due to psychological causality.

The attitudes, knowledge and beliefs of Arab parents in Kuwait about stuttering

An Arabic version of the Public Opinion Survey of Human Attributes Inventory [POSHA-E; St Louis, K. O. (2005), a global instrument to measure public attitudes about stuttering. (The ASHA Leader, 22, 2-13)] was administered to 424 Arab parents of preschool and school age children in 18 government schools across all six governorates in Kuwait. The survey questions pertained to and investigated attitudes, knowledge and beliefs towards stuttering as well as comparative attitudes toward several other conditions. The aim was to identify whether potential barriers existed that might hinder the establishment and conduct of treatment programs for stuttering within Kuwait. These potential barriers might be negative stereotypes, misconceptions about stuttering, cultural beliefs as well as lack of awareness of the disorder within Kuwaiti society. The instrument successfully sampled a variety of beliefs, reactions and emotions that identified cultural beliefs, societal ignorance and confusion about the disorder. It was found that although stuttering appears to be a disorder that most people in Kuwait are aware of and familiar with, their level of knowledge about stuttering in general and about some specific aspects of the disorder was limited. This indicates a need to disseminate scientific information about stuttering in Kuwait and possibly other Arabic speaking countries.

EDUCATIONAL OBJECTIVES

Readers will be able: (1) to evaluate the status of speech-language pathology in Kuwait and the Middle East and compare it to that in other countries, such as Australia and the United States; (2) to list similarities in the stereotypes and attitudes towards stuttering cross-culturally. Readers will also be able to: (3) discuss the differences in knowledge and attitudes according to age, gender and educational level in Kuwait; (4) discuss public awareness and knowledge of stuttering among Arabs in Kuwait specifically.