The experience of stuttering in everyday life among adults who stutter: The impact of trait social anxiety and the social situations.

PURPOSE: The purpose of this study was to investigate the emotional and stuttering experience of adults who stutter (AWS) in everyday life, and how that experience may be shaped by personal (i.e., trait social anxiety) and situational factors (i.e., social partner reaction, communication channel type, social closeness, stuttering knowledge). METHOD: AWS completed ecological momentary assessments on their smartphones multiple times a day for up to three weeks. Data (n = 62) were analyzed with multilevel models to determine how situational factors and trait social anxiety influence the Negative Affect (NA), Positive Affect (PA), and self-reported stuttering severity of AWS. RESULTS: Results indicated that having high (vs. low) trait social anxiety was associated with a tendency to experience high NA, low PA, and high self-reported stuttering severity among AWS. A range of situational factors significantly influenced the within-person variation of NA, PA, and self-reported stuttering severity in everyday life. In addition, interacting with distant social partners relative to being alone heightened NA, and the effect was more prominent among AWS with high (vs. low) trait social anxiety. CONCLUSIONS: Overall, the findings suggest that the variation of affects and stuttering severity among AWS can be partly accounted for by factors from both the situational and personal levels. Clinicians should be aware of the low PA experienced by AWS who have high (vs low) trait social anxiety in everyday life.

Language sample analysis of conversation samples from school-age children who stutter: The role of syntactic factors in stuttering.

INTRODUCTION: The purpose of the study was to compare school-age children who stutter (CWS) and age-matched children who do not stutter (CWNS) in syntactic abilities and syntactic performance. METHODS: Computerized Language Sample Analysis (LSA) was conducted on the conversation samples obtained from 46 school-age CWS and CWNS between 7 and 16 years (CWS, n = 23). Syntactic abilities were assessed using the Index of Productive Syntax (the IPsyn) and Developmental Sentence Scores (DSS) and mixed effects logistic regression analyses with participants as random effects were conducted to determine if the scores were predictive of group membership. Additionally, the groups were compared in the IPsyn subcategories to assess the use of syntactic structures. Syntactic performance was assessed by: (a) Categorizing the sentences from each conversation sample into high vs. low syntactic complexity categories based on DSS scores and comparing the sentence categories in % stuttered sentences (% SS); and (b) Comparing the groups in the proportion of phrase-level disfluencies (phrase repetitions vs. revisions) that are associated with syntactic planning. RESULTS: In terms of syntactic abilities, the IPsyn scores interacted with the number of utterances (sample size) used to compute the scores in predicting group membership. In comparison to the CWNS, the CWS obtained higher scores in the IPsyn and the sentence structure subcategory of the IPsyn that were independent of sample size. In terms of syntactic performance: (a) Significantly more sentences were stuttered in the high compared to the low syntactic sentence category; (b) Compared to the CWNS who demonstrated significantly more phrase revisions, the CWS showed comparable and fewer phrase revisions and repetitions. Additionally, post-hoc analysis showed that the CWS used significantly elaborated noun phrases and a similar trend was evident for verb phrase elaborations. A significant association between verb phrase elaborations and%SS was also obtained. CONCLUSIONS: Findings from the IPsyn and the use of elaborate noun phrases, and to some extent verb phrases, suggested that the CWS used more complex syntax even in shorter conversational samples. More stuttered sentences in the high DSS sentence category, the use of fewer phrase revisions, and the association between stuttering and elaborated verb phrases in the CWS are interpreted to suggest the effects of syntactic planning and reformulation demands on fluency during ongoing articulation.

Effects of task variations on language productivity, syntactic complexity, and stuttering in children who stutter.

PURPOSE: The aim of this preliminary study was to compare the effects of variations in task demands on: (a) language productivity in sentences categorised into stuttered vs. non-stuttered sentences; (b) syntactic complexity in stuttered vs. non-stuttered sentence categories, and (c) stuttering and typical disfluencies in school-age children who stutter (CWS). Language Sample Analysis (LSA) was conducted on samples from three tasks - Conversation, fable retell, and critical thinking based on the fables. METHODS: Participants were 14 CWS categorised into younger (9 to 12-year-olds, n = 8) and older age groups (13 to 15-year-olds, n = 6). The Computerized Language ANalysis program was used to conduct language and disfluency analyses. Repeated measures analysis of variance and nonparametric statistical analyses were used to investigate: (a) Language productivity in total number of words and sentences by task and sentence category; (b) Syntactic complexity at the word- (use of metacognitive verbs), phrase- (use of verb phrases), and utterance (Mean Length of Utterances in words, MLUw) levels by task and sentence category; and (c) Disfluencies measured using % stuttered syllables (%SS) and % typical disfluencies (%TD). RESULTS AND CONCLUSIONS: Task effects in language productivity did not differ by sentence category and suggested limited influences of propositionality and volubility in stuttering. In contrast, higher syntactic complexity was obtained in the stuttered compared to non-stuttered sentences at the word, phrase, and utterance levels and it was the same task - conversation, that elicited the effect. Additionally, variations in task demands did not result in significant differences in %SS. The findings inform assessment planning with the selection of tasks guided by task demands and assessment requirements.

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

PURPOSE: We 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. METHODS: Participants 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. RESULTS: More 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.

Developmental Differences in the Availability of Cognitive Resources Supporting Rhyming and Dual Tasking.

Purpose We investigated developmental differences in a dual task involving rhyming and tone judgment/decisions and the effects of varying cognitive demands on task performance. Method Participants were 7- to 11-year-olds, 12- to 15-year-olds, and adults between 18 and 40 years (n = 19 per group). The rhyming task consisted of three stimuli categories (nonrhyme, rhyme, and replica), and the tone task stimuli were presented at short (100 ms) versus long (900 ms) stimulus onset asynchrony (SOA) from the onset of the rhyme task to vary cognitive demands. Response time (RT) and error data were analyzed using linear and binomial mixed-methods analysis, respectively. Results and Conclusions Adults did not show an SOA-based effect in rhyming RT, while the 12- to 15-year-olds showed the most effect (RT, long > short SOA). Response to the replica category was significantly faster than for the other categories in all age groups. A reverse SOA effect was evident in the tone task (RT, short > long SOA) in all age groups. The 7- to 11-year-olds showed twice the task switch cost effect in the tone task RT. Age grouping and phoneme awareness were significant predictors of performance in both tasks, and additionally, SOA was a significant predictor of performance in the secondary task. The findings have implications for (a) understanding maturational differences in rhyming and executive control for dual tasking and the cognitive mechanisms supporting such effects and (b) identifying variables contributing to the developmental differences.

Investigating the neural correlates of phonological encoding using a cluster-based analysis approach.

Phonological encoding, a subprocess in speech production, proceeds incrementally from word onset to offset. However, the incremental nature of encoding for multisyllabic words is unclear, and limited research has examined neural activity underlying the seriality of the process. In the present study, we investigated the timing of encoding between and within syllables of bisyllabic words using a data-driven cluster-based analysis of electroencephalography (EEG) data. In a phoneme-monitoring task, young adults covertly named pictures of bisyllabic words with a prespecified target phoneme present or absent. Target phonemes in target-present trials were distributed among four serial positions of the word concept: first syllable (S1) onset or offset and second syllable (S2) onset or offset. Upon covert naming, participants responded to target presence via button press or withheld responses for target absence. Neuroelectric activity during task performance was recorded using EEG and analyzed using cluster-based permutation testing. Faster response times and differences in neural activity were observed for monitoring targets at S1 onset than S2 onset, and for monitoring targets at S1 onset than S1 offset. No differences were found between monitoring targets at S2 onset and S2 offset. Our study supports the incremental nature of phonological encoding in bisyllabic words. Furthermore, the neural findings confirm that the serial time course of encoding in bisyllabic words extends to phonemes within the first, but not the subsequent syllable. Findings may have implications for current models of speech production.

Movement kinematics and speech accuracy in a nonword repetition task in school-age children who stutter.

We investigated sensorimotor processes in school-age children who do (CWS) and do not stutter (CWNS) in a nonword repetition (NWR) task and evaluated changes in behavioral (percent speech accuracy) and speech kinematics measures (lip aperture variability, movement duration) with practice and retention. Thirteen CWS and 13 CWNS divided into two age groups (younger, 8-12 years; n = 6, older, 13-15 years, n = 7) repeated nonwords varying in phonological properties over two sessions separated by an hour. Participants in both groups also completed several baseline measures, including tests of digit span and nonword repetition (NRT). A marginal trend for lower speech accuracy was noted in the CWS compared to the CWNS in the NWR task. The younger CWS also performed poorly compared to the older CWS and age-matched CWNS in the NRT. Findings provided weak support for limitations in initial encoding and subsequent retrieval of phonemic information. The CWS demonstrated significantly reduced inter-articulatory coordination for the 3-syllable nonwords. While both groups demonstrated significantly slower movements with increase in nonword complexity at the 3-syllable level, such differences were enhanced in the CWS group and influenced further by participant age. Additionally, digit span influenced movement coordination in both groups with only the CWNS showing a significant negative correlation between the digit span scores and movement variability at the onset of practice in Session 1. The findings offer limited support for a sensorimotor integration deficit in CWS and the contributions of cognitive mechanisms to performance in NWR.

Disfluencies and phonological revisions in a nonword repetition task in school-age children who stutter.

Phonological encoding and associated functions, including monitoring of covert and overt speech, have been attributed relevant roles in stuttering. The aim of this study was to investigate these processes by testing the effects of nonword length in syllables (3-, 4-, 6-syllable), phonotactics, and phonemic/phonetic complexity on disfluencies and phonological revisions in 26 school-age children who stutter (CWS, n = 13) and matched fluent controls (CWNS). Participants repeated nonwords in two sessions separated by an hour. Within-group comparisons of percentage disfluencies using nonparametric tests resulted in significantly more disfluencies for the 6- compared to the 3-syllable nonwords and suggested that nonword length influences disfluencies in the CWS. The groups were comparable in the percentage of disfluencies at all levels of nonword length. The findings failed to provide conclusive evidence that phonological complexity and phonotactic manipulations have a greater effect on disfluencies in CWS compared to CWNS. The findings of significantly fewer phonological revisions and the lack of a significant correlation between disfluencies and revisions in the CWS in Session 1 compared to the CWNS are interpreted to suggest reduced external auditory monitoring. Demands on incremental phonological encoding with increasing task complexity (the Covert Repair Hypothesis, Postma & Kolk, 1993) and reduced external auditory monitoring of stuttered speech can account for the disfluencies, speech errors, and revisions in the speech of school-age CWS.

Backward masking of tones and speech in people who do and do not stutter.

PURPOSE: There is evidence of an auditory-perceptual component of stuttering, and backward masking (BM) is a task to explore that role. Prior research reported poorer thresholds for BM tones in a group of children who persisted in stuttering compared to those for a group that did not persist. This study examined BM for adults who stutter for tones and for speech, which tests a phonetic aspect of hearing. METHOD: Eight persons who stutter (PWS) were closely matched with eight controls (PNS) in terms of phonological abilities, verbal span tasks, age, sex and non-verbal intelligence. These participants were examined for their ability to recognize vowel-consonant (VC) speech syllables and tones in BM paradigm with 0 ms and 300 ms masker to signal onset conditions. RESULTS: PWS showed significantly poorer performance for speech syllable recognition in quiet and in conditions with masking noise. The pattern of speech errors was similar in both groups, but the PWS produced more errors. A significant condition by group interaction in backward masking for tones was attributed to higher masked thresholds in PWS than in PNS in the 0 ms delay condition for BM for tones. CONCLUSION: This was the first study to examine BM for speech in PWS. Results provide support for a small auditory-perceptual deficit for speech understanding in adults who stutter that was revealed in the absence of a lexical context. The speech results are explained in terms of possible indistinct phoneme boundaries in PWS and the effects of vowel context in speech recognition.

The Influence of Executive Functions on Phonemic Processing in Children Who Do and Do Not Stutter.

Purpose: The aim of the present study was to investigate dual-task performance in children who stutter (CWS) and those who do not to investigate if the groups differed in the ability to attend and allocate cognitive resources effectively during task performance. Method: Participants were 24 children (12 CWS) in both groups matched for age and sex. For the primary task, participants performed a phoneme monitoring in a picture-written word interference task. For the secondary task, participants made pitch judgments on tones presented at varying (short, long) stimulus onset asynchrony (SOA) from the onset of the picture. Results: The CWS were comparable to the children who do not stutter in performing the monitoring task although the SOA-based performance differences in this task were more variable in the CWS. The CWS were also significantly slower in making tone decisions at the short SOA and showed a trend for making more errors in this task. Conclusions: The findings are interpreted to suggest higher dual-task cost effects in CWS. A potential explanation for this finding requiring further testing and confirmation is that the CWS show reduced efficiency in attending to the tone stimuli while simultaneously prioritizing attention to the phoneme-monitoring task.

Effects of concurrent task demands on language planning in fluent children and adults.

PURPOSE: The aim of the present study was to investigate how children and adults allocate cognitive resources to performing segmental encoding and monitoring in a dual task paradigm and the response patterns of the primary and secondary tasks in the dual task. METHODS: Participants were 20 children divided equally into two age groups-7 to 11 years, 12 to 15 years, and 10 adults. The primary task required participants to monitor phonemic segments in a picture - written word interference paradigm while silently naming the pictures. The picture and distractor word were the same (replica), related (phoneme onset overlap), or unrelated. The secondary task required participants to make pitch judgments on tones presented at short (330 ms) or long (1130 ms) stimulus onset asynchrony (SOA) from picture onset. RESULTS: Developmental differences were observed in both response times and percent errors in the primary and secondary tasks. Slower responses to the primary task were evident at the long SOA, related condition. Slower response times to the tone decision task were evident at the short than the long SOA. The findings support the capacity sharing account of dual task performance and suggest that dual task costs during language planning are higher in children than adults.

Practice and retention of nonwords in adults who stutter.

PURPOSE: We investigated short-term practice and retention of nonwords in 10 adults who stutter (Mean age=30.7 years, SD=15.1) and age and sex-matched 10 control participants (Mean age=30.8 years, SD=14.9). METHODS: Participants were required to repeat nonwords varying in length (3, 4, and 6 syllables), phonotactic constraint (PC vs. NPC, on 3-syllable nonwords only), and complexity (simple, complex). They were tested twice with 1h gap between sessions. RESULTS: Logistic mixed model of speech accuracy revealed that the AWS showed a significantly lower probability of correct responses with increasing length and complexity. Analysis of speech kinematics revealed practice effects within Session 1 in AWS seen as a reduction in movement variability for the 3-syllable nonwords; the control group was performing at ceiling at this length. For the 4-syllable nonwords, the control group showed a significant reduction in movement variability with practice, and retained this reduction in Session 2, while the AWS group did not show practice or retention. Group differences were not evident at the 6-syllable level. CONCLUSIONS: Group differences in speech accuracy suggest differences in phonemic encoding and/or speech motor processes. Group differences in changes in movement variability within and between sessions suggest reduced practice and retention in AWS. Relevance of the combined use of both behavioral and kinematic measures to interpret the nature of the skill acquisition deficit in persons who stutter is discussed. EDUCATIONAL OBJECTIVES: At the end of this activity the reader will be able to: (a) summarize the process of skill acquisition; (b) discuss the literature on skill acquisition deficits in adults who stutter, (c) summarize the differences between AWS and control participants in speech accuracy and speech kinematics with short-term practice and retention of nonwords, (d) discuss potential research directions in the area of skill acquisition in AWS.

Exploring the link between stuttering and phonology: a review and implications for treatment.

Three lines of research have been pursued in the literature to study the link between phonology and stuttering: (1) effects of phonological complexity on the location (loci) of stutter events; (2) outcomes of standardized test measures in children who do and do not stutter; and (3) studies of phonological encoding in children and adults who stutter. This review synthesizes findings from these three lines of research to address the purported link between phonology and stuttering and its potential implications for stuttering treatment. Results from the loci studies offer some support for the role of phonological complexity in the occurrence of stuttering. Studies of performance in standardized tests of phonology have not identified differences between children who do and do not stutter. Studies of phonological encoding have been equivocal in reporting differences between children and adults who stutter and those who do not stutter. Several cautions are raised in interpreting the findings from the discussed studies, and despite the mixed findings, some implications for treatments are considered.

Nonword repetition and nonword reading abilities in adults who do and do not stutter.

PURPOSE: In the present study a nonword repetition and a nonword reading task were used to investigate the behavioral (speech accuracy) and speech kinematic (movement variability measured as lip aperture variability index; speech duration) profiles of groups of young adults who do (AWS) and do not stutter (control). METHOD: Participants were 9 AWS (8 males, Mean age=32.2, SD=14.7) and 9 age- and sex-matched control participants (Mean age=31.8, SD=14.6). For the nonword repetition task, participants were administered the Nonword Repetition Test (Dollaghan & Campbell, 1998). For the reading task, participants were required to read out target nonwords varying in length (6 vs. 11 syllables). Repeated measures analyses of variance were conducted to compare the groups in percent speech accuracy for both tasks; only for the nonword reading task, the groups were compared in movement variability and speech duration. RESULTS: The groups were comparable in percent accuracy in nonword repetition. Findings from nonword reading revealed a trend for the AWS to show a lower percent of accurate productions compared to the control group. AWS also showed significantly higher movement variability and longer speech durations compared to the control group in nonword reading. Some preliminary evidence for group differences in practice effect (seen as differences between the early vs. later 5 trials) was evident in speech duration. CONCLUSIONS: Findings suggest differences between AWS and control groups in phonemic encoding and/or speech motor planning and production. Findings from nonword repetition vs. reading highlight the need for careful consideration of nonword properties. EDUCATIONAL OBJECTIVES: At the end of this activity the reader will be able to: (a) summarize the literature on nonword repetition skills in adults who stutter, (b) describe processes underlying nonword repetition and nonword reading, (c) summarize whether or not adults who stutter differ from those who do not in the behavioral and kinematic markers of nonword reading performance, (d) discuss future directions for research.

Nonword repetition and phoneme elision skills in school-age children who do and do not stutter.

Nonword repetition and phoneme elision represent the combined influence of several speech and language processes. In the present study we investigated nonword repetition and phoneme elision performance in school-age children who stutter (CWS) and children who do not stutter (CNS). Participants were 14 CWS (mean = 11.7 years, SD = 2.1 years) and age- and sex-matched CNS (mean = 11.8 years, SD = 2.0 years). Each talker group was further subdivided into two age groups: younger (N = 7; 8-11.5 years) and older (N = 7; 11.6-15 years). Repeated-measures analyses were conducted on the accuracy and response time (in seconds) data. In nonword repetition, the CWS showed a trend for lower per cent of correct phonemes at the two-syllable level compared with the CNS. In phoneme elision, the younger CWS showed a significantly lower accuracy rate than the older CWS at the two- and three-syllable nonword lengths, while similar differences were not evident between the younger versus older CNS at any of the nonword lengths. No accuracy difference in phoneme elision was noted between the two talker groups. Group differences in speech initiation times were also not evident in either of the tasks. Findings from nonword repetition offer tentative support for difficulties experienced by school-age CWS in phonemic encoding/working memory abilities. Findings from the phoneme elision task suggest a complex pattern of age-dependent performance by the CWS. Comparison of response accuracy and speech initiation times in both the tasks failed to show speed-accuracy trade-off strategies in either of the groups.

A preliminary investigation of segmentation and rhyme abilities of children who stutter.

UNLABELLED: The present study investigated segmentation and rhyme abilities, skills critical for phonological encoding, of children who stutter (CWS) and those who do not (CNS). Participants were 9 CWS (8 males and 1 female, mean age=11.1, SD=2.31) in the age range of 7 and 13 years and 9 age and sex matched CNS (mean age=11.2, SD=2.19). Participants performed two verbal monitoring tasks, phoneme and rhyme monitoring, in silent naming. Performances in the verbal monitoring tasks were compared to a neutral, nonverbal tone monitoring task. Additionally, the complexity of the phoneme monitoring task was varied such that participants had to monitor for singletons vs. consonant clusters. Repeated measures analysis of the response time data did not reveal significant differences between the groups in the three monitoring tasks. Analysis of the complexity data revealed a trend for slower monitoring of the consonant clusters in the CWS group compared to the CNS. Present findings do not support a deficit in segmentation and rhyme abilities in CWS, although there was some preliminary evidence of segmentation difficulties with increasing phonological complexity of the stimuli. EDUCATIONAL OBJECTIVES: At the end of this activity the reader will be able to: (a) discuss the literature on phonological encoding skills in children who stutter, (b) describe skills underlying the phonological encoding process, (c) summarize whether or not children who stutter differ from those who do not in segmentation and rhyme abilities, (d) suggest future areas of research in the investigation of segmentation and rhyme monitoring abilities in children who stutter.

A preliminary investigation of phonological encoding skills in children who stutter.

PURPOSE: The present study investigated phonological encoding skills in children who stutter (CWS) and those who do not (CNS). Participants were 9 CWS (M=11.8 years, SD=1.5) and 9 age and sex matched CNS (M=11.8 years, SD=1.5). METHOD: Participants monitored target phonemes located at syllable onsets and offsets of bisyllabic words. Performance in the phoneme monitoring task was compared to an auditory tone monitoring task. RESULTS: Repeated measures analysis of the response time data revealed significant Group×Task×Position interaction with the CWS becoming progressively slower than the CNS in monitoring subsequent phonemes located within the bisyllabic words; differences were not observed in the auditory tone monitoring task. Repeated measures analysis of the error data indicated that the groups were comparable in the percent errors in phoneme vs. tone monitoring. The CWS group was also significantly slower in a picture naming task compared to the CNS. CONCLUSIONS: Present findings suggest that CWS experience temporal asynchronies in one or more processes leading up to phoneme monitoring. The findings are interpreted within the scope of contemporary theories of stuttering. EDUCATIONAL OBJECTIVES: At the end of this activity the reader will be able to: (a) discuss the literature on phonological encoding skills in children who stutter, (b) identify theories of phonological encoding in stuttering, (c) define the process of phonological encoding and its implications for fluent speech, (d) suggest future areas of research in the investigation of phonological encoding abilities in children who stutter.

The effects of cognitive: linguistic variables and language experience on behavioural and kinematic performances in nonword learning.

The aim of the present study was to investigate the effects of cognitive-linguistic variables and language experience on behavioral and kinematic measures of nonword learning in young adults. Group 1 consisted of thirteen participants who spoke American English as the first and only language. Group 2 consisted of seven participants with varying levels of proficiency in a second language. Logistic regression of the percent of correct productions revealed short-term memory to be a significant contributor. The bilingual group showed better performance compared to the monolinguals. Linear regression of the kinematic data revealed that the short-term memory variable contributed significantly to movement coordination. Differences were not observed between the bilingual and the monolingual speakers in kinematic performance. Nonword properties including syllable length and complexity influenced both behavioral and kinematic performance. The findings supported the observation that nonword repetition is multiply determined in adults.

Cross-sectional study of phoneme and rhyme monitoring abilities in children between 7 and 13 years.

We investigated phonemic competence in production in three age groups of children - 7 and 8 years, 10 and 11 years, 12 and 13 years-using rhyme and phoneme monitoring. Participants were required to name target pictures silently while monitoring covert speech for the presence or absence of a rhyme or phoneme match. Performance in the verbal tasks was compared to a nonverbal control task in which participants monitored tone sequence pairs for a pattern match. Repeated measures ANOVA revealed significant differences between the three age groups in phoneme monitoring while similar differences were limited to the younger age groups in rhyme monitoring. This finding supported early and on-going acquisition of rhyme- and later acquisition of segment-level units. In addition, the 7 and 8-year-olds were significantly slower in monitoring phonemes within consonant clusters compared to the 10 and 11-year-olds and in monitoring both singleton phonemes and phonemes within clusters compared to the 12 and 13-year-olds. Regression analysis revealed that age accounted for approximately 30% variance in the nonverbal and 60% variance in the verbal monitoring tasks. We attribute the observed differences to the emergence of cognitive processes such as segmentation skills that are critical to performing the verbal monitoring tasks.

Language and motor abilities of preschool children who stutter: evidence from behavioral and kinematic indices of nonword repetition performance.

UNLABELLED: Stuttering is a disorder of speech production that typically arises in the preschool years, and many accounts of its onset and development implicate language and motor processes as critical underlying factors. There have, however, been very few studies of speech motor control processes in preschool children who stutter. Hearing novel nonwords and reproducing them engages multiple neural networks, including those involved in phonological analysis and storage and speech motor programming and execution. We used this task to explore speech motor and language abilities of 31 children aged 4-5 years who were diagnosed as stuttering. We also used sensitive and specific standardized tests of speech and language abilities to determine which of the children who stutter had concomitant language and/or phonological disorders. Approximately half of our sample of stuttering children had language and/or phonological disorders. As previous investigations would suggest, the stuttering children with concomitant language or speech sound disorders produced significantly more errors on the nonword repetition task compared to typically developing children. In contrast, the children who were diagnosed as stuttering, but who had normal speech sound and language abilities, performed the nonword repetition task with equal accuracy compared to their normally fluent peers. Analyses of interarticulator motions during accurate and fluent productions of the nonwords revealed that the children who stutter (without concomitant disorders) showed higher variability in oral motor coordination indices. These results provide new evidence that preschool children diagnosed as stuttering lag their typically developing peers in maturation of speech motor control processes. EDUCATIONAL OBJECTIVES: The reader will be able to: (a) discuss why performance on nonword repetition tasks has been investigated in children who stutter; (b) discuss why children who stutter in the current study had a higher incidence of concomitant language deficits compared to several other studies; (c) describe how performance differed on a nonword repetition test between children who stutter who do and do not have concomitant speech or language deficits; (d) make a general statement about speech motor control for nonword production in children who stutter compared to controls.