Bilingual children who stutter: Convergence,gaps and directions for research

PurposeThe aim of this systematic review is to examine the early interactions between bilingualism and stuttering to synthesize knowledge that could inform diagnosis and treatment for bilingual children who stutter.MethodScopus, Science Direct, PubMed, ERIC Ebsco, and Google Scholar were searched with no limits placed on the year of publication. Search terms consisted of: (“stuttering” [MeSH] OR “stutter”) AND (“child” [MeSH] OR “children”) AND (“multilingualism” [MeSH] OR “bilingualism”). Inclusion criteria were children who stutter, bilinguals who stutter, empirical research articles, and published in peer review journals. Exclusion criteria were studies that reported on only adults, only monolinguals, or were not published in English.ResultsA total of 50 articles met the criteria. There was convergence with monolingual studies reporting sexually dimorphic and familial trends in the prevalence of stuttering and rates of recovery. Findings surrounding language proficiency, cross-linguistic stuttering severity, and development were ambivalent. Results point to the difficulty in identifying stuttering in bilingual children, and the need for culturally competent research and interpretations.ConclusionCurrent findings offer a fragmented view of bilingual development and echoes a recurring theme, i.e., the current understanding of bilingualism and stuttering is limited and more research is warranted.     

Children and adolescents who stutter: Further investigation of anxiety

PurposeDespite the greatly increased risk of social anxiety disorder in adults who stutter, there is no clear indication of the time of onset of this disorder in childhood and adolescence. The purpose of this study was to explore this issue further using the Revised Children's Manifest Anxiety Scale (RCMAS), so that appropriate interventions can be developed prior to adulthood. This is the first time the RCMAS has been completed by children younger than 11 years. Using the same test for both school-age children and adolescents can potentially identify when anxiety starts to develop from age 6 years through to adulthood.MethodsThe RCMAS was administered to 18 school-age boys, five school-age girls, 41 adolescent boys and nine adolescent girls who were seeking treatment for their stuttering. Participants also rated the severity of their own stuttering.ResultsAll mean scaled scores on the four RCMAS subscales and Total Anxiety scores were within normal limits. However, for both groups of boys, scores on the Lie Scale were significantly higher than scores on the other three subscales.ConclusionsExperts suggest high scores on the RCMAS Lie Scale are indicative of participants attempting to present themselves in a positive light and so cast doubt on the veracity of their other responses on the test. One interpretation, then, is that the boys were concealing true levels of anxiety about their stuttering. The results suggest why findings of anxiety studies in children and adolescents to date are equivocal. Clinical implications are discussed.Educational objectives: The reader will be able to: (a) discuss why understanding when anxiety starts in people who stutter is important, (b) describe the function of the RCMAS Lie sub scale and (c) summarize the possible implications of the RCMAS findings in this study.     

Bilinguals who stutter: A cognitive perspective

PurposeBrain 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.MethodsA 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.ResultsA 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.ConclusionPrevious 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.     

Visual exogenous and endogenous attention and visual memory in preschool children who stutter

PurposeAttention develops gradually from infancy to the preschool years and beyond. Exogenous attention, consisting of automatic responses to salient stimuli, develops in infancy, whereas endogenous attention, or voluntary attention, begins to develop later, in the preschool years. The purpose of this study was to examine (a) exogenous and endogenous attention in young children who stutter (CWS) and children who do not stutter (CWNS) through two conditions of a visual sustained selective attention task, and (b) visual short-term memory (STM) between groups within the context of this task.Method42 CWS and 42 CWNS, ages 3;0–5;5 (years;months), were pair-matched in age, gender (31 males, 11 females per group), and socioeconomic status. Children completed a visual tracking task (Track-It Task; Fisher et al., 2013) requiring sustained selective attention and engaging exogenous and endogenous processes. Following each item, children were asked to recall the item they had tracked, as a memory check.ResultsThe CWS group demonstrated significantly less accuracy in overall tracking and visual memory for the tracked stimuli, compared to the CWNS group. Across groups, the children performed better in sustained selective attention when the target stimuli were more salient (the condition tapping both exogenous and endogenous attention) than when stimuli were less so (the condition tapping primarily endogenous processes).ConclusionsRelative to peers, preschool-age CWS, as a group, display weaknesses in visual sustained selective attention and visual STM.     

Comparison of pausing behavior in children who stutter and children who have Asperger syndrome

Purpose

The objective of this research was to compare the number and types of grammatical and non-grammatical silent pauses presented by stutterers and subjects with Asperger syndrome in their narratives.

Method

Ten children who stutter and four participants with Asperger syndrome (mean ages of both groups 10 years) were assessed at the Speech and Language Disorders Department of the Universidade Federal de São Paulo/Brasil. They narrated a story based on a pre-selected sequence of pictures. They were filmed and their productions were analyzed using version 5.0.47 of Praat (http://www.fon.hum.uva.nl/praat/download_win.html). Silent intervals in the speech that ranged from 0.25 to 4 s were considered pauses. The pauses were classified as grammatical and non-grammatical, depending on the words that preceded and followed them.

Results

Both groups presented grammatical and non-grammatical pauses and the former predominated. The children with Asperger syndrome produced a greater number of pauses than the stutterers.Educational objectives: The reader will be able to: (1) characterize the use of pauses in the oral narrative; (2) distinguish a grammatical pause from a non-grammatical pause regarding the use and function; (3) recognize the pattern of pause found in the two populations.     

Effect of phonological and morphological factors on speech disfluencies of Kannada speaking preschool children who stutter

PurposeEmpirical investigations have revealed a strong association between linguistic factors and stuttering, specifically phonological and morphological factors. However, the effect of these factors is suggested to vary across languages owing to the differences in their linguistic structure. Further, the trend is found to vary between AWS and CWS. Literature in this regard is scarce in the Kannada language, particularly in children. Hence, the study was driven by the need to understand the effect of phonological and morphological factors on stuttering in Kannada speaking CWS.MethodSpontaneous speech samples were obtained from twenty Kannada speaking preschool CWS with a confirmed diagnosis of stuttering by an experienced speech-language pathologist. The recorded samples were transcribed, and disfluencies were marked. Further, the stuttered words were analysed for phonological and morphological features. The phonological factors included were phoneme position in a word, phoneme type and word length. Morphological factors consisted of word class and word end inflectional morphology. The percentage of stuttering was calculated with respect to each of the factors mentioned above.ResultsPhoneme in the initial position of a word and words beginning with consonants had a higher rate of stuttering. Word length, word class and word end inflections were found to have no significant effect on the rate of stuttering in CWS.ConclusionOverall, current findings revealed that stuttering might manifest differently across languages varying in their linguistic structures.     

Communication attitudes in children who stutter: A meta-analytic review

BackgroundThis article presents a meta-analytic review of differences in communication attitudes between children who stutter (CWS) and children who do not stutter (CWNS).MethodTo be included in this review, the studies had to include a group of CWS and CWNS between the ages of 3–18 years and a measurement of communication attitudes. The journal articles were identified by using the key words stutter*, speech disfluenc*, fluency disorder*, and stammer* cross-referenced to awareness*, reaction*, attitude*, KiddyCAT, CAT, A-19 Scale, PASS and OASES.ResultsA total of 18 studies met the inclusion criteria for this meta-analysis. The results showed that CWS exhibit more negative communication attitudes than CWNS from the preschool years. The differences between the groups increased with age, but were not influenced by gender.ConclusionThe results indicate that negative communication attitudes can be an effect of stuttering. Key issues requiring further investigation are whether communication attitudes differ as a function of age at stuttering onset and whether communication attitudes influence the development of stuttering.Educational Objectives: After reading this article, the reader will be able to: (a) summarise empirical findings with regard to the relationship between communication attitudes and childhood stuttering; (b) describe the different instruments used to measure communication attitudes; (c) discuss the relationship between communication attitudes, age and gender.     

Speech sound articulation abilities of preschool-age children who stutter

Purpose

The purpose of this study was to assess the association between speech sound articulation and childhood stuttering in a relatively large sample of preschool-age children who do and do not stutter, using the Goldman–Fristoe Test of Articulation-2 (GFTA-2; Goldman & Fristoe, 2000).

Method

Participants included 277 preschool-age children who do (CWS; n = 128, 101 males) and do not stutter (CWNS; n = 149, 76 males). Generalized estimating equations (GEE) were performed to assess between-group (CWS versus CWNS) differences on the GFTA-2. Additionally, within-group correlations were performed to explore the relation between CWS’ speech sound articulation abilities and their stuttering frequency and severity, as well as their sound prolongation index (SPI; Schwartz & Conture, 1988).

Results

No significant differences were found between the articulation scores of preschool-age CWS and CWNS. However, there was a small gender effect for the 5-year-old age group, with girls generally exhibiting better articulation scores than boys. Additional findings indicated no relation between CWS’ speech sound articulation abilities and their stuttering frequency, severity, or SPI.

Conclusions

Findings suggest no apparent association between speech sound articulation—as measured by one standardized assessment (GFTA-2)—and childhood stuttering for this sample of preschool-age children (N = 277).Educational objectives: After reading this article, the reader will be able to: (1) discuss salient issues in the articulation literature relative to children who stutter; (2) compare/contrast the present study's methodologies and main findings to those of previous studies that investigated the association between childhood stuttering and speech sound articulation; (3) identify future research needs relative to the association between childhood stuttering and speech sound development; (4) replicate the present study's methodology to expand this body of knowledge.     

Atypical central auditory speech-sound discrimination in children who stutter as indexed by the mismatch negativity

PurposeRecent theoretical conceptualizations suggest that disfluencies in stuttering may arise from several factors, one of them being atypical auditory processing. The main purpose of the present study was to investigate whether speech sound encoding and central auditory discrimination, are affected in children who stutter (CWS).MethodsParticipants were 10 CWS, and 12 typically developing children with fluent speech (TDC). Event-related potentials (ERPs) for syllables and syllable changes [consonant, vowel, vowel-duration, frequency (F0), and intensity changes], critical in speech perception and language development of CWS were compared to those of TDC.ResultsThere were no significant group differences in the amplitudes or latencies of the P1 or N2 responses elicited by the standard stimuli. However, the Mismatch Negativity (MMN) amplitude was significantly smaller in CWS than in TDC. For TDC all deviants of the linguistic multifeature paradigm elicited significant MMN amplitudes, comparable with the results found earlier with the same paradigm in 6-year-old children. In contrast, only the duration change elicited a significant MMN in CWS.ConclusionsThe results showed that central auditory speech-sound processing was typical at the level of sound encoding in CWS. In contrast, central speech-sound discrimination, as indexed by the MMN for multiple sound features (both phonetic and prosodic), was atypical in the group of CWS. Findings were linked to existing conceptualizations on stuttering etiology.Educational objectives: The reader will be able (a) to describe recent findings on central auditory speech-sound processing in individuals who stutter, (b) to describe the measurement of auditory reception and central auditory speech-sound discrimination, (c) to describe the findings of central auditory speech-sound discrimination, as indexed by the mismatch negativity (MMN), in children who stutter.     

Emotional reactivity and regulation in preschool-age children who stutter

Purpose.

This study experimentally investigated behavioral correlates of emotional reactivity and emotion regulation and their relation to speech (dis)fluency in preschool-age children who do (CWS) and do not (CWNS) stutter during emotion-eliciting conditions.

Method.

Participants (18 CWS, 14 boys; 18 CWNS, 14 boys) completed two experimental tasks (1) a neutral (“apples and leaves in a transparent box,” ALTB) and (2) a frustrating (“attractive toy in a transparent box,” ATTB) task, both of which were followed by a narrative task. Dependent measures were emotional reactivity (positive affect, negative affect), emotion regulation (self-speech, distraction) exhibited during the ALTB and the ATTB tasks, percentage of stuttered disfluencies (SDs) and percentage of non-stuttered disfluencies (NSDs) produced during the narratives.

Results.

Results indicated that preschool-age CWS exhibited significantly more negative emotion and more self-speech than preschool-age CWNS. For CWS only, emotion regulation behaviors (i.e., distraction, self-speech) during the experimental tasks were predictive of stuttered disfluencies during the subsequent narrative tasks. Furthermore, for CWS there was no relation between emotional processes and non-stuttered disfluencies, but CWNS's negative affect was significantly related to nonstuttered disfluencies.

Conclusions.

In general, present findings support the notion that emotional processes are associated with childhood stuttering. Specifically, findings are consistent with the notion that preschool-age CWS are more emotionally reactive than CWNS and that their self-speech regulatory attempts may be less than effective in modulating their emotions.Educational objectives. The reader will be able to: (a) communicate the relevance of studying the role of emotion in developmental stuttering close to the onset of stuttering and (b) describe the main findings of the present study in relation to previous studies that have used different methodologies to investigate the role of emotion in developmental stuttering of young children who stutter.     

Developing physiologic stress profiles for school-age children who stutter

Purpose

Physiologic reactivity profiles were generated for 9 school-age children with a history of stuttering. Utilizing salivary sampling, stress biomarkers cortisol and alpha-amylase were measured in response to normal daily stressors. Children with a history of stuttering were characterized as high or low autonomic reactors when compared to age-normed references established for cortisol and alpha-amylase levels.

Method

Salivary samples were collected four times daily over three consecutive days from children (6 boys and 3 girls) aged 6–11 years. Samples were measured for two important stress biomarkers, cortisol and alpha-amylase. Following laboratory training on appropriate sampling technique using the Salivette, families collected all samples in their homes.

Results

Compared to published references established for normal children, children with a history of stuttering exhibited mean cortisol and alpha-amylase levels that were significantly lower, though within normal limits.

Conclusions

Results reflect an initial investigation into the use of salivary sampling to measure reactivity in children who stutter. As children who stutter have historically been excluded from physiologic stress studies, salivary sampling appears to provide an innovative and minimally invasive option for investigators. Though interpreted with caution secondary to the small sample size, initial findings suggest that in response to normal daily stressors, school-age children with a history of stuttering do not exhibit significantly elevated stress biomarkers.Educational objectives: The reader will be able to: (1) identify two biomarkers that reflect activation of the body's stress response; (2) discuss possible implications the generation of individualized stress profiles may have on the treatment of stuttering; and (3) discuss and evaluate the research needs associated with the inclusion of children in physiological studies of fluency.     

A comparison of the performance of Persian speaking children who do and do not stutter on three nonwords repetition tasks

PurposeThe purpose of the study was to examine the performance of Persian speaking children who stutter (CWS) and children who do not stutter (CWNS) on three nonword repetition tasks, while also focusing on which task and scoring method best differentiates the two groups of children.MethodThirty CWS and 30 CWNS between the ages of 5;0 to 6;6 completed three nonword repetition tasks that varied in complexity. Each task was scored using two methods: nonwords correct and phonemes correct. Between-group differences in performance on each task were examined, along with disfluencies for CWS and the task and scoring method that best differentiated the CWS and CWNS.ResultsThe findings revealed that, across all three nonword repetition tasks, the CWS consistently produced fewer nonwords correct and phonemes correct than the CWNS group at virtually all syllable lengths. The CWS produced more disfluencies on longer nonwords than shorter nonwords in all three nonword repetition tasks. The nonword repetition task with lower wordlikeness and more phonologically complex items best differentiated the two groups of children. Findings further revealed that discriminative accuracy was highest for scoring based on the number of phonemes produced correctly.ConclusionFindings provide further evidence to suggest that CWS may have difficulty with phonological working memory and/or phonological processing.     

Rhyming abilities in a dual-task in school-age children who stutter

PurposeWe compared school-age children who stutter (CWS) and age and gender matched control participants (CWNS) in a dual-task involving a word-level rhyming task and a tone task involving pitch decisions.MethodsParticipants were 30 children (CWS, n = 15) between 7 and 16 years. Auditory word – picture stimuli pairs from the rhyme task were categorized into nonrhyme (e.g., bear-cart), rhyme (e.g., bear-pear), and replica (e.g., bear-bear) categories. The effort associated with managing resources in the dual-task was varied through the manipulation of stimulus onset asynchrony (SOA) between the stimuli of the two tasks. Mixed methods analyses of the response time (RT, ms) and error (%) data were conducted with Group, Category, and SOA as the fixed effects and participants as the random effect. Age and phoneme awareness skills were included in the analyses.ResultsMore rhyming errors and a significant positive correlation between rhyming errors and age was observed in the CWS compared to the CWNS. Compared to the CWNS, a higher percentage of rhyming errors was observed in the rhyme than the nonrhyme and replica categories in the CWS in both the SOA conditions, and this effect was influenced by age and phoneme awareness skills. Analysis of the tone task data indicated that a subgroup of CWNS with higher phoneme awareness skills showed reduced RT difference between the long and the short SOA conditions thereby suggesting higher efficiency with resource allocation for dual tasking. Task-specific differences between the CWS and CWNS are interpreted to suggest limitations in the encoding of the phonological aspects of covert speech in a dual-task.     

Delayed N2 response in Go condition in a visual Go/Nogo ERP study in children who stutter

Purpose of the studyThe main aim of the study was to investigate the attentional and inhibitory abilities and their underlying processes of children who stutter by using behavioural measurement and event-related potentials (ERP) in a visual Go/Nogo paradigm.MethodsParticipants were 11 children who stutter (CWS; mean age 8.1, age range 6.3–9.5 years) and 19 typically developed children (TDC; mean age 8.1, age range 5.8–9.6 years). They performed a visual Go/Nogo task with simultaneous EEG recording to obtain ERP responses.ResultsResults showed that CWS had longer N2 and P3 latencies in the Go condition compared to the TDC. In contrast, the groups did not differ significantly in the Nogo condition or behavioural measures.ConclusionsOur findings did not confirm less efficient inhibitory control in CWS but suggest atypical attentional processing such as stimulus evaluation and response selection.Educational Objectives: The reader will be able to (a) describe recent findings on attention and inhibitory control in children who stutter, (b) describe the measurement of attentional processing, including inhibitory control, and (c) describe the findings on attentional processing in children who stutter as indexed by the event-related potentials in a visual Go/Nogo paradigm.     

Effects of perceptual and conceptual similarity in lexical priming of young children who stutter: preliminary findings

The purpose of this study was to investigate the influence of conceptual and perceptual properties of words on the speed and accuracy of lexical retrieval of children who do (CWS) and do not stutter (CWNS) during a picture-naming task. Participants consisted of 13 3–5-year-old CWS and the same number of CWNS. All participants had speech, language, and hearing development within normal limits, with the exception of stuttering for CWS. Both talker groups participated in a picture-naming task where they named, one at a time, computer-presented, black-on-white drawings of common age-appropriate objects. These pictures were named during four auditory priming conditions: (a) a neutral prime consisting of a tone, (b) a word prime physically related to the target word, (c) a word prime functionally related to the target word, and (d) a word prime categorically related to the target word. Speech reaction time (SRT) was measured from the offset of presentation of the picture target to the onset of participant's verbal speech response. Results indicated that CWS were slower than CWNS across priming conditions (i.e., neutral, physical, function, category) and that the speed of lexical retrieval of CWS was more influenced by functional than perceptual aspects of target pictures named. Findings were taken to suggest that CWS tend to organize lexical information functionally more so than physically and that this tendency may relate to difficulties establishing normally fluent speech and language.

Educational objectives: The reader will learn about and be able to (1) communicate the relevance of examining lexical retrieval in relation to childhood stuttering and (2) describe the method of measuring speech reaction times of accurate and fluent responses during a picture-naming task as a means of assessing lexical retrieval skills.     

Loci of stuttering of English- and Korean-speaking children who stutter: Preliminary findings

PurposeThe purpose of the study was to determine whether differences exist between young English- and Korean-speaking children who stutter (CWS) in the loci of stuttering.MethodParticipants were 10 Korean-speaking and 11 English-speaking CWS between the ages of 3 and 7 years. Participants produced narratives while viewing various picture scenes and a wordless picture book.ResultsFindings indicated that Korean-speaking CWS stuttered more on content than function words whereas English-speaking CWS stuttered more on function than content words. Furthermore, both Korean- and English-speaking CWS tended to stutter more on utterance-initial words. These findings appear to be related to the differences in linguistic/syntactic structures between Korean and English. Specifically, in the Korean-speaking CWS’s narratives, most utterance-initial words (73.60 %) were content words whereas in the English-speaking CWS’s narratives, most utterance-initial words (83.57 %) were function words.ConclusionThese preliminary findings, although in need of replication with a larger sample size, seem to suggest that the word class (i.e., content/function words) contributions to stuttering loci are more language-specific whereas the word position (i.e., utterance-initial position) contributions to stuttering loci are more language-nonspecific. Given that the true characteristics of stuttering may be rather language-nonspecific than language-specific, further research may need to focus more on stuttering loci related to word position than word class.     

A positron emission tomography study of short- and long-term treatment effects on functional brain activation in adults who stutter

Previous studies have shown that fluency-inducing techniques, such as choral speech, result in changes in neural activation as measured by functional neuroimaging. In the present study, positron emission tomography was used to investigate the effects of intensive behavioural treatment, followed by a 1-year maintenance program, on the pattern of cortical and subcortical activation in stuttering adults during silent and oral reading of single words. The results indicate changes in activation lateralisation, as well as a general reduction in overactivation, especially in the motor cortex, following treatment. The results are discussed in light of previous functional imaging studies with stuttering adults.

Educational objectives: The reader will learn about and be able to describe the: (1) use of functional neuroimaging PET in the study of stuttering; (2) differences in neural activation between stuttering and non-stuttering adults; and (3) effects of behavioural fluency treatment on cortical and subcortical activations in stuttering speakers.     

Elevated attention deficit hyperactivity disorder symptoms in children who stutter

PurposeThis study described the proportion of children who stutter who exhibit Attention Deficit Hyperactivity Disorder (ADHD) symptoms, manifesting in inattentive and hyperactive/impulsive behaviours. Children who stutter with these challenging behaviours may not respond as quickly and successfully to stuttering treatment. A preliminary exploration of differences in treatment responsiveness for children with and without ADHD symptoms was undertaken.MethodParticipants were 185 preschool children who stutter who had completed stuttering therapy within 3 months prior to study commencement. Differences between groups of children who stutter with and without elevated ADHD symptoms were investigated, in terms of pre-treatment stuttering features (stuttering severity and typography), demographic variables (age at onset, time between onset and commencement of therapy, family history and sex) and treatment data (post-treatment stuttering severity and number of sessions to achieve discharge criteria).ResultsOne-half (50%) of participants exhibited elevated ADHD symptoms. These children required 25% more clinical intervention time to achieve successful fluency outcomes than children without elevated ADHD symptoms. Findings suggest that more ADHD symptoms, increased pre-treatment stuttering severity, and male sex were associated with poorer responsiveness to stuttering treatment.ConclusionThe large proportion of children exhibiting elevated ADHD symptoms, and the increase in clinical contact time required in this subgroup to achieve successful fluency outcomes, is suggestive of the need for clinicians to tailor stuttering intervention to address these concomitant behaviour challenges. Findings support the use of careful caseload management strategies to account for individual differences between children, and strengthen prognostic information available to parents and clinicians.