Effects of behavior inhibition on stuttering severity and adverse consequences of stuttering in 3-6-year-old children who stutter.

PURPOSE: The purpose of this study was to investigate whether 3- to-6-year-old children who stutter and exhibit a higher degree of behavioral inhibition (BI), a correlate of shyness, stutter more frequently and experience greater negative consequences of stuttering (per parent-report) than their peers who stutter but have lower BI. METHOD: Forty-six children who stutter (CWS; 35 boys & 11 girls; mean age 4 years, 2 months) participated. Their degree of BI was assessed by measuring the latency to their 6th spontaneous comment during a conversation with an unfamiliar examiner (following Kagan, Reznick, & Gibbons's (1989) methodology). The frequency of stuttering and the negative impact of stuttering that CWS may have experienced was assessed using parent reports (i.e., Test of Childhood Stuttering (TOCS) Observational Rating Scale; Gillam, Logan, & Pearson, 2009). RESULTS: We found that children's degree of BI was not associated with their speech fluency per parent report. However, children's degree of BI was significantly associated with greater negative consequences of stuttering. Specifically, among the four categories of TOCS Disfluency-Related Consequences, children's BI significantly predicted the occurrence of physical behaviors that accompany moments of stuttering (such as increased tension or excessive eye blinks). Other Disfluency-Related Consequences, such as avoidance behaviors, negative feelings, and negative social consequences, were not associated with children's behavioral inhibition tendencies. Additionally, children's stuttering severity (per the Stuttering Severity Instrument-4 scores) was significantly associated with increased physical behaviors that accompany moments of stuttering and greater negative social consequences of stuttering. CONCLUSIONS: This study provides empirical evidence that behavioral inhibition to the unfamiliar may have salience for childhood stuttering as it predicted the development of physical behaviors associated with stuttering (e.g., tension or struggle) in 3- to 6-year-old CWS. Clinical implications of high BI for the assessment and treatment of childhood stuttering are discussed.

Psychophysiological Arousal in Young Children Who Stutter: An Interpretable AI Approach.

The presented first-of-its-kind study effectively identifies and visualizes the second-by-second pattern differences in the physiological arousal of preschool-age children who do stutter (CWS) and who do not stutter (CWNS) while speaking perceptually fluently in two challenging conditions: speaking in stressful situations and narration. The first condition may affect children's speech due to high arousal; the latter introduces linguistic, cognitive, and communicative demands on speakers. We collected physiological parameters data from 70 children in the two target conditions. First, we adopt a novel modality-wise multiple-instance-learning (MI-MIL) approach to classify CWS vs. CWNS in different conditions effectively. The evaluation of this classifier addresses four critical research questions that align with state-of-the-art speech science studies' interests. Later, we leverage SHAP classifier interpretations to visualize the salient, fine-grain, and temporal physiological parameters unique to CWS at the population/group-level and personalized-level. While group-level identification of distinct patterns would enhance our understanding of stuttering etiology and development, the personalized-level identification would enable remote, continuous, and real-time assessment of stuttering children's physiological arousal, which may lead to personalized, just-in-time interventions, resulting in an improvement in speech fluency. The presented MI-MIL approach is novel, generalizable to different domains, and real-time executable. Finally, comprehensive evaluations are done on multiple datasets, presented framework, and several baselines that identified notable insights on CWSs' physiological arousal during speech production.

Effects of Physiological Arousal on Speech Motor Control and Speech Motor Practice in Preschool-Age Children Who Do and Do Not Stutter.

Purpose We examined the effects of physiological arousal on speech motor control and speech motor practice effects in preschool-age children who do (CWS) and do not stutter (CWNS). Method Participants included 18 CWS (M age = 4 years 5 months) and 18 age- and gender-matched CWNS. The participants repeated a phrase "buy bobby a puppy" interspersed with viewing pictures from the International Affective Picture System under two experimental conditions speaking after viewing pictures with (a) negative and (b) neutral valence. Participants' lip movements were tracked using Optotrak system. The spatiotemporal index and mean utterance duration were calculated to examine speech motor control and speech motor practice effects. Skin conductance level was measured during the experimental conditions to assess participants' physiological level of arousal. Results Preschool-age CWS demonstrated greater speech movement variability across all conditions and trials than CWNS. Furthermore, the younger participants produced more variable articulatory movements than the older participants. Participants' speech movement variability did not significantly differ between the negative and neutral experimental conditions, and the level of physiological arousal did not have a significant effect on it. There was a nonsignificant trend of decrease in speech movement variability across the repeated trials in both groups. Last, CWS and CWNS did not differ in their mean utterance duration, suggesting that their articulation rate was similar across all conditions and trials. Conclusions Our findings indicate that, compared to preschool-age CWNS, CWS demonstrate less mature speech motor control. However, present findings do not support the hypothesis that CWS benefit less from motor practice relative to CWNS. Given that our conditions elicited similar levels of arousal in the participants, future research is needed to examine whether physiological arousal disrupts speech motor control in preschool-age children potentially contributing to disruptions of speech fluency and the development of stuttering.

The Role of Behavioral Inhibition for Conversational Speech and Language Characteristics of Preschool-Age Children Who Stutter.

Purpose The purpose of this study was to investigate whether preschool-age children who stutter (CWS) were more likely to exhibit a temperamental trait of behavioral inhibition (BI), a correlate of shyness, than children who do not stutter (CWNS) and whether this temperamental trait affected preschool-age children's speech fluency and language complexity during a conversation with an unfamiliar adult. Method Sixty-eight preschool-age children (31 CWS, 37 CWNS) participated. The degree of BI was assessed by measuring the latency to their sixth spontaneous comment and the number of all spontaneous comments during a conversation with an unfamiliar examiner (following Kagan et al.'s [1987] methodology). Parent report of shyness from the Children's Behavior Questionnaire served as an indirect measure of BI. Children's language complexity was assessed by measuring their mean length of utterance and the number of words spoken. For CWS, the frequency of stuttering and the negative impact of stuttering were also assessed. Results First, we found no between-group differences in the degree of BI across the behavioral observation measures. However, CWS were rated shyer by parents than CWNS. Second, for CWS only, higher BI was associated with less complex utterances and fewer words spoken. Third, for CWS, higher BI was associated with fewer stuttered disfluencies produced. Conclusions This study provides empirical evidence that BI to the unfamiliar may have salience for childhood stuttering as it affected the quantity and quality of language spoken with an unfamiliar adult. Clinical implications of high BI for the assessment and treatment of preschool-age stuttering are discussed.

Emotional Reactivity and Regulation in Preschool-Age Children Who Do and Do Not Stutter: Evidence From Autonomic Nervous System Measures.

Purpose: This experimental cross-sectional research study examined the emotional reactivity and emotion regulation in preschool-age children who do (CWS) and do not stutter (CWNS) by assessing their psychophysiological response during rest and while viewing pictures from the International Affective Picture System (Lang et al., 2008). Method: Participants were 18 CWS (16 boys and two girls; mean age 4 years, 5 months) and 18 age- and gender-matched CWNS. Participants' psychophysiological responses were measured during two baselines and two picture viewing conditions. Skin conductance level (SCL) and heart rate were measured to assess emotional reactivity. Respiratory sinus arrhythmia (RSA) was measured to assess emotional regulation. Participants' shyness and executive function were assessed via parent report and considered for their effects on participants' psychophysiological responses. Results: First, CWNS and CWS did not differ in their initial baseline SCL, heart rate, or RSA, but all participants had higher SCL and lower RSA in the second baseline, subsequent to the first challenge condition, compared to the first baseline. Second, during the challenge conditions, CWS did not differ from CWNS in their SCL, but showed a significantly higher heart rate than CWNS. Third, CWS exhibited a significantly lower RSA during the challenge conditions compared to CWNS. Lastly, the temperamental quality of shyness was associated with preschool-age children's SCL, such that participants who were rated higher in shyness had a higher SCL during the challenge conditions. Participants' executive function had a marginally significant effect on the RSA, such that the participants who had higher executive function composite scores exhibited lower RSA during the challenge conditions. Conclusions: Our findings suggest that CWS and CWNS did not differ in their emotional reactivity and emotional regulation abilities at rest. During challenge conditions, however, CWS tended to be more emotionally reactive, as indicated by a higher heart rate, and also employed more emotional regulation, indexed by a greater decrease in RSA, compared to CWNS. Preschool-age children's behavior is largely dominated by reactivity, but there is the emergence of regulation, which can help children adjust to various contextual demands. For CWS who are more emotionally reactive, regulatory skills may be particularly critical to their prognosis and treatment.

Autonomic Nervous System Response to Speech Production in Stuttering and Normally Fluent Preschool-Age Children.

Purpose We studied speech-related sympathetic nervous system arousal of preschool-age children who do (CWS) and do not stutter (CWNS) and its association with children's proclivity to experience negative emotions and children's self-reported attitudes toward speaking. Method Electrodermal activity measures were collected from 32 preschool-age children while they engaged in a picture description and a nonword repetition task. Children's proclivity to experience negative emotions was assessed with a parent report questionnaire. Children's communication attitude was assessed with a self-report questionnaire. Results CWS did not differ from CWNS in their sympathetic arousal during a picture description task. However, during a more challenging nonword repetition task, preschool-age CWS had a higher sympathetic arousal level than CWNS. Although CWS were rated by their caregivers as more fearful and prone to sadness, children's tendency to experience stronger and more frequent negative emotions was not associated with their sympathetic arousal during speaking. Lastly, although CWS had a more negative communication attitude than CWNS, it was not associated with their level of sympathetic arousal during speaking. Conclusions Our findings suggest that age-appropriate social communication tasks are not inherently more stressful for preschool-age CWS and are not associated with state-related stress or anxiety that is often reported for adults who stutter. However, speaking tasks that place a higher demand on children's cognitive-linguistic system may be more taxing and challenging to preschool CWS than CWNS, leading to a higher level of arousal.

Expressed parental concern regarding childhood stuttering and the Test of Childhood Stuttering.

PURPOSE: The purpose of the present study was to determine whether the Test of Childhood Stuttering observational rating scales (TOCS; Gillam et al., 2009) (1) differed between parents who did versus did not express concern (independent from the TOCS) about their child's speech fluency; (2) correlated with children's frequency of stuttering measured during a child-examiner conversation; and (3) correlated with the length and complexity of children's utterances, as indexed by mean length of utterance (MLU). METHOD: Participants were 183 young children ages 3:0-5:11. Ninety-one had parents who reported concern about their child's stuttering (65 boys, 26 girls) and 92 had parents who reported no such concern (50 boys, 42 girls). Participants' conversational speech during a child-examiner conversation was analyzed for (a) frequency of occurrence of stuttered and non-stuttered disfluencies, and (b) MLU. Besides expressing concern or lack thereof about their child's speech fluency, parents completed the TOCS observational rating scales documenting how often they observe different disfluency types in speech of their children, as well as disfluency-related consequences. RESULTS: There were three main findings. First, parents who expressed concern (independently from the TOCS) about their child's stuttering reported significantly higher scores on the TOCS Speech Fluency and Disfluency-Related Consequences rating scales. Second, children whose parents rated them higher on the TOCS Speech Fluency rating scale produced more stuttered disfluencies during a child-examiner conversation. Third, children with higher scores on the TOCS Disfluency-Related Consequences rating scale had shorter MLU during child-examiner conversation, across age and level of language ability. CONCLUSIONS: Findings support the use of the TOCS observational rating scales as one documentable, objective means to determine parental perception of and concern about their child's stuttering. Findings also support the notion that parents are reasonably accurate, if not reliable, judges of the quantity and quality (i.e., stuttered vs. non-stuttered) of their child's speech disfluencies. Lastly, findings that some children may decrease their verbal output in attempts to minimize instances of stuttering - as indexed by relatively low MLU and a high TOCS Disfluency-Related Consequences scores - provides strong support for sampling young children's speech and language across various situations to obtain the most representative index possible of the child's MLU and associated instances of stuttering.

Young children's family history of stuttering and their articulation, language and attentional abilities: An exploratory study.

PURPOSE: The purpose of this study was to determine whether young children who do (CWS) and do not stutter (CWNS) with a positive versus negative family history of stuttering differ in articulation, language and attentional abilities and family histories of articulation, language and attention related disorders. METHOD: Participants were 25 young CWS and 50 young CWNS. All 75 participants' caregivers consistently reported a positive or negative family history of stuttering across three consecutive time points that were about 8 months apart for a total of approximately 16 months. Each participant's family history focused on the same, relatively limited number of generations (i.e., participants' parents & siblings). Children's family history of stuttering as well as articulation, language, and attention related disorders was obtained from one or two caregivers during an extensive interview. Children's speech and language abilities were measured using four standardized articulation and language tests and their attentional abilities were measured using caregiver reports of temperament. RESULTS: Findings indicated that (1) most caregivers (81.5% or 75 out 92) were consistent in their reporting of positive or negative history of stuttering; (2) CWNS with a positive family history of stuttering, compared to those with a negative family history of stuttering, were more likely to have reported a positive family history of attention deficit/hyperactivity disorder (ADHD), and (3) CWNS with a positive family history of stuttering had lower language scores than those with a negative family history of stuttering. However, there were no such significant differences in family histories of ADHD and language scores for CWS with a positive versus negative family history of stuttering. In addition, although 24% of CWS versus 12% of CWNS's caregivers reported a positive family history of stuttering, inferential analyses indicated no significant differences between CWS and CWNS in relative proportions of family histories of stuttering. CONCLUSION: Finding that a relatively high proportion (i.e., 81.5%) of caregivers consistently reported a positive or negative family history of stuttering across three consecutive time points should provide some degree of assurance to those who collect such caregiver reports. Based on such consistent caregiver reports, linguistic as well as attentional vulnerabilities appear associated with a positive family history of stuttering, a finding that must await further empirical study for confirmation or refutation.

Motor practice effects and sensorimotor integration in adults who stutter: Evidence from visuomotor tracking performance.

PURPOSE: The purpose of this study was to utilize a visuomotor tracking task, with both the jaw and hand, to add to the literature regarding non-speech motor practice and sensorimotor integration (outside of auditory-motor integration domain) in adults who do (PWS) and do not (PWNS) stutter. METHOD: Participants were 15 PWS (14 males, mean age = 27.0) and 15 PWNS (14 males, mean age = 27.2). Participants tracked both predictable and unpredictable moving targets separately with their jaw and their dominant hand, and accuracy was assessed by calculating phase and amplitude difference between the participant and the target. Motor practice effect was examined by comparing group performance over consecutive tracking trials of predictable conditions as well as within the first trial of same conditions. RESULTS: Results showed that compared to PWNS, PWS were not significantly different in matching either the phase (timing) or the amplitude of the target in both jaw and hand tracking of predictable and unpredictable targets. Further, there were no significant between-group differences in motor practice effects for either jaw or hand tracking. Both groups showed improved tracking accuracy within and between the trials. CONCLUSION: Our findings revealed no statistically significant differences in non-speech motor practice effects and integration of sensorimotor feedback between PWS and PWNS, at least in the context of the visuomotor tracking tasks employed in the study. In general, both talker groups exhibited practice effects (i.e., increased accuracy over time) within and between tracking trials during both jaw and hand tracking. Implications for these results are discussed. EDUCATIONAL OBJECTIVES: The reader will be able to: (a) describe the importance of motor learning and sensory-motor integration for speech, (b) summarize past research on PWS's performance during speech and nonspeech motor tasks, and (c) describe the relation between different aspects of speech and non-speech motor control and stuttering.

Speech disfluencies of preschool-age children who do and do not stutter.

PURPOSE: The goals of the present study were to investigate whether (1) the speech disfluencies of preschool-age children are normally distributed; (2) preschool-age children who do (CWS) and do not stutter (CWNS) differ in terms of non-stuttered disfluencies; (3) age, gender, and speech-language ability affect the number and type of disfluencies children produce; and (4) parents' expressed concern that their child stutters is associated with examiners' judgments of stuttered disfluency. METHOD: Four hundred and seventy two children participated, of which 228 were CWS (56 girls), and 244 CWNS (119 girls). Participants provided conversational speech samples that were analyzed for frequency of occurrence of (a) stuttered disfluencies, (b) non-stuttered disfluencies, and (c) total disfluencies. RESULTS: Results indicated that the underlying distributions of preschool-age children's stuttered and non-stuttered disfluency counts followed a negative binomial distribution (i.e., were not normal), with more children "piling up" at the low end [none or few disfluencies] and fewer children scoring in the upper [more severe stuttering] end of the distribution. Findings also indicated that non-stuttered disfluencies significantly predicted CWS/CWNS talker group classification, information that may be helpful to augment, but not supplant, talker group classification criteria based on stuttered disfluencies. Moreover, expressed parental concern about stuttering was strongly associated with frequency of stuttered disfluencies. CONCLUSION: Findings suggest that the entirety of preschool-age CWS' speech disfluencies - non-stuttered as well as stuttered - differs from that of their CWNS peers and that because these disfluencies are not normally distributed statistical analyses assuming normality of distribution are not the most appropriate means to assess these differences. In addition, certain "third-order" variables (e.g., gender) appear to impact frequency of children's disfluencies and expressed parental concerns about stuttering are meaningfully related to examiners' judgments of stuttered disfluencies. LEARNING OUTCOMES: The reader will recognize differences in speech disfluencies of preschool-age children who do and do not stutter. The reader will recognize whether age, gender and speech-language ability affect the number and type of disfluencies children produce. The reader will describe whether parental concern about stuttering is associated with examiners' judgments of stuttering.

Autonomic nervous system activity of preschool-age children who stutter.

PURPOSE: The purpose of this study was to investigate potential differences in autonomic nervous system (ANS) activity to emotional stimuli between preschool-age children who do (CWS) and do not stutter (CWNS). METHODS: Participants were 20 preschool-age CWS (15 male) and 21 preschool-age CWNS (11 male). Participants were exposed to two emotion-inducing video clips (negative and positive) with neutral clips used to establish pre-and post-arousal baselines, and followed by age-appropriate speaking tasks. Respiratory sinus arrhythmia (RSA)-often used as an index of parasympathetic activity-and skin conductance level (SCL)-often used as an index of sympathetic activity-were measured while participants listened to/watched the audio-video clip presentation and performed a speaking task. RESULTS: CWS, compared to CWNS, displayed lower amplitude RSA at baseline and higher SCL during a speaking task following the positive, compared to the negative, condition. During speaking, only CWS had a significant positive relation between RSA and SCL. CONCLUSION: Present findings suggest that preschool-age CWS, when compared to their normally fluent peers, have a physiological state that is characterized by a greater vulnerability to emotional reactivity (i.e., lower RSA indexing less parasympathetic tone) and a greater mobilization of resources in support of emotional reactivity (i.e., higher SCL indexing more sympathetic activity) during positive conditions. Thus, while reducing stuttering to a pure physiological process is unwarranted, the present findings suggest that the autonomic nervous system is involved. EDUCATIONAL OBJECTIVES: The reader will be able to: (a) summarize current empirical evidence on the role of emotion in childhood stuttering; (b) describe physiological indexes of sympathetic and parasympathetic activity; (c) summarize how preschool-age children who stutter differ from preschool-age children who do not stutter in autonomic activity; (d) discuss possible implications of current findings in relation to the development of childhood stuttering.

Behavioral inhibition and childhood stuttering.

PURPOSE: The purpose of this study was to assess the relation of behavioral inhibition to stuttering and speech/language output in preschool-age children who do (CWS) and do not stutter (CWNS). METHOD: Participants were preschool-age (ages 36-68 months), including 26 CWS (22 males) and 28 CWNS (13 males). Participants' behavioral inhibition (BI) was assessed by measuring the latency to their sixth spontaneous comment during conversation with an unfamiliar experimenter, using methodology developed by Kagan, Reznick, and Gibbons (1989). In addition to these measures of BI, each participant's stuttered and non-stuttered disfluencies and mean length of utterance (in morphemes) were assessed. RESULTS: Among the more salient findings, it was found that (1) there was no significant difference in BI between preschool-age CWS and CWNS as a group, (2) when extremely high versus low inhibited children were selected, there were more CWS with higher BI and fewer CWS with lower BI when compared to their CWNS peers, and (3) more behaviorally inhibited CWS, when compared to less behaviorally inhibited CWS, exhibited more stuttering. CONCLUSIONS: Findings are taken to suggest that one aspect of temperament (i.e., behavioral inhibition) is exhibited by some preschool-age CWS and that these children stutter more than CWS with lower behavioral inhibition. The present results seem to support continued study of the association between young children's temperamental characteristics and stuttering, the diagnostic entity (i.e., CWS versus CWNS), as well as stuttering, the behavior (e.g., frequency of stuttered disfluencies). EDUCATIONAL OBJECTIVES: After reading this article, the reader will be able to: (a) summarize the salient empirical findings in the extant literature with regard to the association between temperament and childhood stuttering; (b) describe the concept of behavioral inhibition (BI) as well as the methods to measure BI; and (c) discuss the association between behavioral inhibition and childhood stuttering in preschool-age children.

Articulation rate and its relationship to disfluency type, duration, and temperament in preschool children who stutter.

UNLABELLED: The purpose of this study was to examine the relationship between articulation rate, frequency and duration of disfluencies of different types, and temperament in preschool children who stutter (CWS). In spontaneous speech samples from 19 CWS (mean age=3:9; years:months), we measured articulation rate, the frequency and duration of (a) sound prolongations; (b) sound-syllable repetitions; (c) single syllable whole word repetitions; and (d) clusters. Temperament was assessed with the Children's Behavior Questionnaire (Rothbart et al., 2001). There was a significant negative correlation between articulation rate and average duration of sound prolongations (p<0.01), and between articulation rate and frequency of stuttering-like disfluencies (SLDs) (p<0.05). No other relationships proved statistically significant. Results do not support models of stuttering development that implicate particular characteristics of temperament as proximal contributors to stuttering; however, this is likely due to the fact that current methods, including the ones used in the present study, do not allow for the identification of a functional relationship between temperament and speech production. Findings do indicate that for some CWS, relatively longer sound prolongations co-occur with relatively slower speech rate, which suggests that sound prolongations, across a range of durations, may represent a distinct type of SLD, not just in their obvious perceptual characteristics, but in their potential influence on overall speech production at multiple levels. LEARNING OUTCOMES: Readers will be able to describe the relationship between stuttering-like disfluencies, articulation rate and temperament in children who stutter, and discuss different measurements of articulation rate.