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

Associations between social anxiety, physiological reactivity, and speech disfluencies in autistic young adults and controls

INTRODUCTION

The aim of this study was to examine possible associations of social anxiety (SA) and speaking-related physiological reactivity with the frequencies of a) total disfluencies, b) typical disfluencies, and c) stuttering-like disfluencies, as well as d) stuttering-severity in autistic young adults and controls.

METHODS

Thirty-two autistic young adults and 35 controls participated in this study. Participants were presented with video clips (viewing condition) and were then asked to talk about the videos (narrating condition). SA was measured by the self-report Social Phobia and Anxiety Inventory (SPAI). Speaking-related physiological reactivity was measured by the electrodermal activity (EDA), an index of emotional arousal. The speech samples from the narrating condition were analyzed for type and frequency of speech disfluencies and used for determining the stuttering severity. SA and speaking-related physiological reactivity were compared between the groups. Correlation between SA, physiological reactivity, disfluency frequencies, and stuttering severity were tested separately for both groups.

RESULTS

No between-group differences were found in the overall SA, yet differences were found in SPAI subscales of social interaction, group interaction, and avoidance, as well as in agoraphobia. Both groups had higher physiological arousal in narrating condition in comparison to the video viewing condition, yet there was no between-group difference in the reactivity. No associations were found between SPAI measures, physiological reactivity, disfluency frequencies, and stuttering severity in the autistic group. In the control group, a negative association was found between physiological reactivity and total and typical disfluency frequencies.

CONCLUSIONS

SA or speaking-related physiological reactivity were not associated with disfluency frequencies or stuttering severity in autistic persons. Negative association between physiological reactivity and disfluency frequencies found in the control group may indicate that the physiological arousal may impact the speech production process by reducing the overt disfluencies.

Electrodermal Activity of Preschool-Age Children Who Stutter During a Child-Friendly Stroop Paradigm

PURPOSE

The aim of the study was to assess whether emotional reactivity, indexed by a distinct physiological measure of sympathetic activation, differs between preschool-age children who stutter (CWS) and preschool-age children who do not stutter (CWNS) during a child-friendly Stroop task (i.e., day-night task). Additionally, researchers aimed to assess whether the Stroop task, compared to a control task, was a significant physiological stressor.

METHOD

Fifteen preschool-age CWS and 22 preschool-age CWNS were asked to perform a day-night Stroop task in order to elicit psychophysiological reactivity, indexed by electrodermal response (EDR) occurrence frequency and EDR amplitude. Physiological measurements were recorded during pretask baselines, performance of the day-night Stroop task, and performance of a speech-language control task.

RESULTS

Findings based on EDR measures did not support the hypothesis that the child-friendly day-night Stroop task is an effective stressor as compared to a control task based on measures of physiological arousal in preschool-age children. The CWS and CWNS did not significantly differ in their EDR measures relative to the control task or Stroop task (p > .05). However, CWS, compared to CWNS, exhibited significantly greater EDR amplitudes during the control task baseline (p < .05) and the Stroop task baseline (p < .05).

CONCLUSION

Overall, these findings may suggest that a predisposition to heightened levels of sympathetic activity prior to tasks in preschool-age CWS is important to consider with regard to the nature of developmental stuttering.

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.

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.

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.