Cognitive flexibility in preschool children with and without stuttering disorders

Mental state verb use in play by preschool-age children who stutter and their mothers

INTRODUCTION

Preschool-age children use mental state verbs (MSVs; e.g., think, know) to reference thoughts and other cognitive states. In play-based language, MSV use requires conversational flexibility, as speakers shift from discussion of actions happening in the here-and-now to more abstract discussion of mental states. Some evidence suggests that children who stutter (CWS) demonstrate subtle differences in shifting on experimental tasks of cognitive flexibility, differences which may extend to conversational flexibility. This study explored MSV use in conversational language between CWS and their mothers.

METHODS

Thirty-five preschool-age CWS and 35 age- and gender-matched children who do not stutter (CWNS), all performing within the typical range on standardized language testing, conversed with their mothers during play. Samples were transcribed and coded for MSV use.

RESULTS

No between-group differences were observed in MSV use, either between the CWS and CWNS or between the groups of mothers. Age and language skills were positively associated with MSV use in the CWNS group only. For both groups of dyads, mothers' MSV use corresponded at least to some extent to their children's language skills. Finally, correspondence between CWNS and their mothers was observed for two conversational language measures, representing lexical diversity and morphosyntax; this overall pattern was not observed in the CWS dyad group.

CONCLUSIONS

Although these findings point to similar use of MSVs among the groups of children and their mothers, for the CWS group, the patterns of use in relation to age and language skills are somewhat different from developmental expectations.

Inhibitory Control, Cognitive Flexibility, and the Production of Disfluencies in Children Who Do and Do Not Stutter

PURPOSE

Differences in inhibitory control and cognitive flexibility between children who stutter (CWS) and children who do not stutter (CWNS) have been previously demonstrated. The aim of the current study was to investigate whether the previously reported inhibitory control- and cognitive flexibility-related performance costs for CWS are associated with the number of speech disfluencies that they produce.

METHOD

Participants were 19 CWS (Mage = 7.58 years, range: 6.08-9.17) and 19 CWNS matched on age and gender (Mage = 7.58 years, range: 6.08-9.33). Gamma regression models were used to investigate possible associations between performance costs in speed and accuracy measured during a computer task evaluating inhibitory control and cognitive flexibility and the number of speech disfluencies during video-recorded speech samples (story retelling and casual conversation).

RESULTS

Two significant interactions were observed. For both inhibitory control and cognitive flexibility, we identified a significant group and inhibitory control/cognitive flexibility performance-cost interaction in stuttering-like disfluencies (SLDs), indicating that the performance-cost effects on SLD production were significantly higher in the CWS group, compared to the CWNS group.

CONCLUSIONS

CWS with reduced inhibitory control or cognitive flexibility produce more SLDs, but not other disfluencies. These results are partly in line with some previous findings in nonstuttering and stuttering populations linking inhibitory control and cognitive flexibility weaknesses to the production of speech disfluencies.

Complex working memory in adults with and without stuttering disorders: Performance patterns and predictive relationships

PURPOSE

Available studies of working memory (WM) in speakers who stutter tend to rely on parent report, focus on phonological WM, or measure WM in combination with other processes. The present research aimed to: (1) compare complex WM in adults who stutter (AWS) and adults who do not stutter (AWNS); (2) characterize group performance patterns; and (2) determine whether WM predicts stuttering severity.

METHODS

Eighteen AWS and 20 AWNS completed parallel verbal and spatial span tasks in which to-be-remembered items were interleaved with a distracting task across varying set sizes. Dependent variables included the number of correctly recalled items, accuracy on distraction tasks, and detailed analyses of item-level responses. We further examined whether span scores predicted subjective and objective measures of stuttering severity.

RESULTS

Relative to AWNS, AWS showed poorer recall, specifically on short set sizes in the spatial task. Groups performed similarly on distraction tasks and showed comparable error patterns. Predictive relationships differed by span task and severity measure. Lower verbal span scores predicted greater stuttering impact and more overt stuttering behaviors; lower spatial span scores predicted lower impact and was unrelated to overt behaviors.

CONCLUSIONS

Findings suggest that AWS differ subtly from AWNS in WM performance. Group differences became more apparent under certain task conditions but could not be attributed to specific underlying processes. Data further indicated a complex relationship between WM and stuttering severity. Overall, results corroborate previous studies linking stuttering to domain-general weaknesses, but highlight the need for additional research to clarify the nature of this relationship.

T-PALS framework to assess children who stutter with coexisting disorders: A tutorial

The purpose of this paper is to present a tutorial on a diagnostic framework developed to assess children who stutter and exhibit co-existing disorders. While we have guidelines for treating these children, there are no specific guidelines for assessing them. We provide a rationale for the development of T-PALS with support from the literature. The T-PALS framework assesses 5 foundational key elements for the child: Temperament (T), Pragmatics (P), Articulation/phonology (A), Language (L), and Stuttering (S). Both qualitative and quantitative measures are used within each dimension. This framework is discussed with reference to using two clinical case examples. T-PALS observation data are presented as well as treatment suggestions for each case. We conclude that T-PALS may be a useful framework for both clinicians and researchers, working with children who present with stuttering and comorbid conditions. Clinicians are encouraged to reach beyond the traditional focus on solely assessing the stuttering behavior, even when that is the main concern for referral, and to consider a broader view of the child. It is hoped that this more integrative approach to assessment may yield a more holistic diagnostic picture of a dual diagnosis child from which treatment goals can be derived.

EEG-biomarker theta/beta ratio and attentional quotients in adults who stutter: An electrophysiological and behavioral study

INTRODUCTION

There is increasing evidence that connects developmental stuttering to attention. However, findings have represented contradiction. Therefore, this study was conducted to investigate the possible relationship between stuttering and attention in resting and undertask conditions.

METHODS

In a cross-sectional study, 26 right-handed AWS (adults who stutter) and 25 matched fluent speakers were enrolled. Demographic data were collected, and the Beck anxiety inventory (BAI) was filled out for all participants. Then, QEEG was conducted, followed by IVA2. CPT test for all subjects. Finally, data were analyzed using SPSS software version 16.

RESULTS

AWS indicated significantly weaker auditory focus attention in the task (p = .02) than the control group, while a similar resting-state EEG marker of attention was found between groups (p > .05). Moreover, attention was not correlated between the two conditions (p > .05).

CONCLUSION

The EEG marker of attention did not necessarily designate the attentional performance of AWS under the task. Furthermore, attentional skills could be considered in the assessment and therapeutic programs of at least some groups of AWS.

Complex response inhibition and cognitive flexibility in school-aged Cypriot-Greek-speaking children who stutter

PURPOSE

Over the last few years, research findings have suggested limitations in executive function (EF) of children who stutter (CWS) with the evidence being more consistent in studies with preschoolers (3-6  years old) than in studies with school-aged children (6-12  years old). The purpose of the current study was to assess complex response inhibition and cognitive flexibility in school-aged CWS and their non-stuttering peers.

METHODS

Participants, 19 CWS (mean age = 7.58  years, range 6.08-9.17) and 19 age-and gender-matched children who do not stutter (CWNS; mean age = 7.58  years, range 6.08-9.33), completed a visual task consisting of three task blocks. Analyses were based on response times and error percentages during the different task blocks.

RESULTS

All participants showed expected performance-costs in task block comparisons targeting complex response inhibition and cognitive flexibility. Significant group differences were found in measures of cognitive flexibility with CWS performing slower compared to CWNS (p = 0.02). Additionally, significant block × group interactions demonstrated that CWS, compared to CWNS, slowed down more (i.e., higher performance-cost) under both complex response inhibition (p = 0.049) and cognitive flexibility task conditions (p = 0.04 for no-set-shifting and p = 0.02 for set-shifting).

CONCLUSION

These results are in line with some of the previous findings in school-aged CWS and suggest that CWS present lower performance in complex response inhibition and cognitive flexibility task conditions when compared to their non-stuttering peers.

Cognitive flexibility in younger and older children who stutter

PURPOSE

Recent research findings suggest possible weaknesses in cognitive flexibility (CF) in children who stutter (CWS) when compared to children who do not stutter (CWNS). Studies so far, have been conducted with either younger (3-6 years old) or older children (6-12 years old) with a variety of measures. The purpose of the present study was to investigate CF with the use of a single behavioral measure across a broader age range (4-10 years old).

METHODS

Participants were 37 CWS (mean age = 6.90 years) and 37 age-and gender-matched CWNS (mean age = 6.88 years), divided in a younger (below 7 years) and older (above 7 years) age group. All participants undertook a computerized visual set-shifting task consisting of three blocks. CF was evaluated through across-and within-block comparisons of the actual response speed and accuracy values. In addition, mixing-and set-shifting-costs were evaluated based on the mean response speed and accuracy.

RESULTS

All participants showed expected mixing-and set-shifting-costs. Only the within-block analyses yielded significant between (sub)group differences. Investigation of the block × classification group × age group interactions showed that older CWS had larger set-shifting-costs (slowed down more and made more errors) compared to older CWNS.

CONCLUSION

While all participants required more time during set-shifting trials, only the older CWS (7-10 years old), and not younger CWS, were slower and made more errors. This finding corroborates previous findings in CWS of a similar age and could possibly point to a role of CF in stuttering persistence.

Dual-Task Effects on Concurrent Speech Production in School-Age Children With and Without Stuttering Disorders

PURPOSE

Contemporary motor theories indicate that well-practiced movements are best performed automatically, without conscious attention or monitoring. We applied this perspective to speech production in school-age children and examined how dual-task conditions that engaged sustained attention affected speech fluency, speech rate, and language productivity in children with and without stuttering disorders.

METHOD

Participants included 47 children (19 children who stutter, 28 children who do not stutter) from 7 to 12 years of age. Children produced speech in two baseline conditions with no concurrent task and under a dual-task condition requiring sustained attention to on-screen stimuli. Measures of speech fluency, speech rate, and language productivity were obtained for each trial and compared across conditions and groups.

RESULTS

Dual-task conditions resulted in a reduction in stutter-like disfluencies relative to the initial baseline speaking condition. Effects were similar for both groups of children and could not be attributed to decreases in language productivity or a simple order effect.

CONCLUSIONS

Findings suggest that diverting attention during the process of speech production enhances speech fluency in children, possibly by increasing the automaticity of motor speech sequences. Further research is needed to clarify neurophysiological mechanisms underlying these changes and to evaluate potential clinical applications of such effects.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19945838.

Emotion-related regulation strategy use in preschool-age children who stutter

PURPOSE

Past findings indicate the quality and quantity of emotion regulation often differs between preschool-age children who stutter (CWS) and children who do not stutter (CWNS). The purpose of this study was to identify whether specific emotion-related regulatory strategy types differ between preschool-age CWS and CWNS during a temptation task.

METHODS

Participants were 13 CWS and 13 CWNS between 3;2 and 5;7 (years;months), matched for gender and age (+/- 6 months). Participants completed a Forbidden Toy paradigm, a resistance to temptation task, in which the children were asked to refrain from touching a toy. Types of emotion-related regulation, including (1) verbal regulation, (2) behavioral regulation, and (3) attentional regulation, were behaviorally coded during the temptation task.

RESULTS

A higher proportion of the CWNS (92%) failed to resist the temptation to touch the toy than CWS (48%). Additionally, a higher proportion of the CWS (23%), compared to CWNS (0%), presented with signs of distress, resulting in their task ending prematurely. Limited differences were detected in the types of emotion-related regulatory strategies used by CWS, or the frequency of those strategies. CWNS, compared to the CWS, used more approach-related behavioral strategies.

CONCLUSIONS

Interpretations of these findings must be mitigated by the observation that a higher proportion of CWS than CWNS demonstrated distress during the paradigm, suggesting a need for further research into the interplay between emotional reactivity and emotion regulation for preschool-age CWS.

Complex nonverbal response inhibition and stopping impulsivity in childhood stuttering

PURPOSE

The primary purpose of this study was to examine complex nonverbal response inhibition and stopping impulsivity in children who do (CWS) and do not stutter (CWNS).

METHOD

A total of 30 CWS and 30 CWNS between the ages of 3;1 and 6;0 (years; months) performed the Peg-Tapping Task (PTT; Diamond & Taylor, 1996; Luria, 1966), in which children were required to tap a dowel once when an examiner taps twice and vice versa. The main dependent variables were the number of practice trials, response accuracy, response latency for accurate responses, and the number of extra taps (i.e., tapping more than two times).

RESULTS

The CWS were less accurate and slower on the PTT than the CWNS, with no differences in the number of practice trials. Furthermore, the CWS, especially boys, produced more extra taps than the CWNS.

CONCLUSIONS

Findings revealed that preschool CWS have weaknesses in complex response inhibition and stopping impulsivity in the nonverbal domain compared to CWNS. Taken together, these findings along with those of previous studies indicate that CWS may have weaknesses in inhibition and impulsivity in the nonverbal domain as well as the verbal domain, suggesting a domain-general weakness.

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.

Cognitive Flexibility and Effortful Control in School-Age Children With and Without Stuttering Disorders

Purpose This study compared attention control and flexibility in school-age children who stutter (CWS) and children who do not stutter (CWNS) based on their performance on a behavioral task and parent report. We used a classic attention-shifting paradigm that included manipulations of task goals and timing to test effects of varying demands for flexibility on switching accuracy and speed. We also examined associations between task performance, group, and relevant aspects of temperament. Method Participants included 33 children (15 CWS, 18 CWNS) between 8 and 11 years of age. Children sorted stimuli that differed on two dimensions (color and shape) based on sorting rules that varied from block to block or trial to trial. Timing manipulations included intervals of 200-, 600-, or 1,200-ms durations for critical trial components. Temperament data were obtained via the Children's Behavior Questionnaire. Results All children showed expected performance costs in response to block and trial manipulations; however, CWS were more affected by task conditions that increased demands for cognitive flexibility. Effects of interval durations also differed by group. Factor scores on the Children's Behavior Questionnaire indicated differences in effortful control between groups; however, this aspect of temperament did not mediate between-groups differences in switching performance. Conclusions Findings suggest that stuttering continues to be associated with differences in attention control and flexibility beyond the preschool years. Further research is needed to clarify how these cognitive processes shape the development of stuttering throughout childhood.

A Preliminary Investigation of Attention-Deficit/Hyperactivity Disorder Characteristics in Adults Who Stutter

Purpose Recent studies have shown that many children who stutter may have elevated characteristics of attention-deficit/hyperactivity disorder (ADHD). Although childhood ADHD commonly persists into adulthood, it is unclear how many adults who stutter experience aspects of ADHD (e.g., inattention or hyperactivity/impulsivity). This study sought to increase understanding of how ADHD characteristics might affect individuals who stutter by evaluating (a) whether elevated ADHD characteristics are common in adults who stutter, (b) whether elevated ADHD characteristics in adults who stutter were significantly associated with greater adverse impact related to stuttering, and (c) whether individual differences in Repetitive Negative Thinking (RNT) and Effortful Control influenced this relationship. Method Two hundred fifty-four adults who stutter completed the Adult ADHD Self-Report Scale, the Perseverative Thinking Questionnaire, the Adult Temperament Questionnaire short form, and the Overall Assessment of the Speaker's Experience of Stuttering. Data were analyzed via multiple linear regression to determine whether the number of inattention or hyperactivity/impulsivity characteristics was significantly associated with RNT, Effortful Control, or Adverse Impact related to stuttering. Results Almost one quarter of participants (23.2%; 60/254) self-reported experiencing six or more inattention characteristics, while fewer participants (8.3%; 21/254) self-reported experiencing six or more hyperactivity/impulsivity characteristics. Participants with lower Effortful Control and higher levels of both RNT and Adverse Impact were significantly more likely to self-report experiencing more inattention characteristics. Discussion Many adults who stutter may exhibit previously unaccounted for characteristics of ADHD, especially inattention. Results highlight the value of continued research on the intersectionality of stuttering, ADHD, and attention, and the importance of individualizing therapy to the needs of each unique person who stutters.

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.

Cognitive Flexibility for Semantic and Perceptual Information in Developmental Stuttering

Purpose The purpose of this study was to examine cognitive flexibility for semantic and perceptual information in preschool children who stutter (CWS) and who do not stutter (CWNS). Method Participants were 44 CWS and 44 CWNS between the ages of 3;0 and 5;11 (years;months). Cognitive flexibility was measured using semantic and perceptual categorization tasks. In each task, children were required to match a target object with two different semantic or perceptual associates. Main dependent variables were reaction time and accuracy. Results The accuracy with which CWS and CWNS shifted between one semantic and perceptual representation to another was similar, but the CWS did so significantly more slowly. Both groups of children had more difficulty switching between perceptual representations than semantic ones. Conclusion CWS are less efficient (slower), though not less accurate, than CWNS in their ability to switch between different representations in both the verbal and nonverbal domains.

Associations between stuttering, comorbid conditions and executive function in children: a population-based study

Background

The aim of this study was to investigate the relationship between executive function (EF), stuttering, and comorbidity by examining children who stutter (CWS) and children who do not stutter (CWNS) with and without comorbid conditions. Data from the National Health Interview Survey were used to examine behavioral manifestations of EF, such as inattention and self-regulation, in CWS and CWNS.

Methods

The sample included 2258 CWS (girls = 638, boys = 1620), and 117,725 CWNS (girls = 57,512; boys = 60,213). EF, and the presence of stuttering and comorbid conditions were based on parent report. Descriptive statistics were used to describe the distribution of stuttering and comorbidity across group and sex. Regression analyses were to determine the effects of stuttering and comorbidity on EF, and the relationship between EF and socioemotional competence.

Results

Results point to weaker EF in CWS compared to CWNS. Also, having comorbid conditions was also associated with weaker EF. CWS with comorbidity showed the weakest EF compared to CWNS with and without comorbidity, and CWS without comorbidity. Children with stronger EF showed higher socioemotional competence. A majority (60.32%) of CWS had at least one other comorbid condition in addition to stuttering. Boys who stutter were more likely to have comorbid conditions compared to girls who stutter.

Conclusion

Present findings suggest that comorbidity is a common feature in CWS. Stuttering and comorbid conditions negatively impact EF.

Adult stuttering and attentional ability: A meta-analytic review

Purpose: The study presents the first review in which the link between attentional ability and developmental stuttering is explored. The review aimed to summarise the published research literature and provide a more conclusive understanding as to the relationship between stuttering and attention.Method: To be included in this review, the studies had to compare the attentional performance of adult people who stutter (PWS) and people who do not stutter (PWNS) over the age of 18 years with a validated psychometric instrument for measuring attentional ability. Articles were searched in four electronic databases where each of the following search terms (attention, vigilance, inhibitory, inhibition, interference, executive and processing) was cross-referenced with each of the following terms (stutter, stammer, speech disfluency and speech dysfluency). A total of 21 studies met the inclusion criteria to be submitted into a meta-analysis.Result: The results of the main meta-analysis, which included all selected studies, demonstrated that PWS had a significantly worse attentional performance as compared to PWNS. Two further meta-analyses on selective attention and dual tasking performance confirmed the latter finding. Importantly, however, the effect was not present in all studies.Conclusion: Our findings should be taken as an indication that stuttering sometimes (but not always) manifests together with poorer attentional ability, such that the identified link does not affect all PWS. These results provide support for the notion that there is a close association between stuttering and attentional ability in a subgroup of PWS, highlighting potential practical implications for stuttering treatment.

The Application of EEG Mu Rhythm Measures to Neurophysiological Research in Stuttering

Deficits in basal ganglia-based inhibitory and timing circuits along with sensorimotor internal modeling mechanisms are thought to underlie stuttering. However, much remains to be learned regarding the precise manner how these deficits contribute to disrupting both speech and cognitive functions in those who stutter. Herein, we examine the suitability of electroencephalographic (EEG) mu rhythms for addressing these deficits. We review some previous findings of mu rhythm activity differentiating stuttering from non-stuttering individuals and present some new preliminary findings capturing stuttering-related deficits in working memory. Mu rhythms are characterized by spectral peaks in alpha (8-13 Hz) and beta (14-25 Hz) frequency bands (mu-alpha and mu-beta). They emanate from premotor/motor regions and are influenced by basal ganglia and sensorimotor function. More specifically, alpha peaks (mu-alpha) are sensitive to basal ganglia-based inhibitory signals and sensory-to-motor feedback. Beta peaks (mu-beta) are sensitive to changes in timing and capture motor-to-sensory (i.e., forward model) projections. Observing simultaneous changes in mu-alpha and mu-beta across the time-course of specific events provides a rich window for observing neurophysiological deficits associated with stuttering in both speech and cognitive tasks and can provide a better understanding of the functional relationship between these stuttering symptoms. We review how independent component analysis (ICA) can extract mu rhythms from raw EEG signals in speech production tasks, such that changes in alpha and beta power are mapped to myogenic activity from articulators. We review findings from speech production and auditory discrimination tasks demonstrating that mu-alpha and mu-beta are highly sensitive to capturing sensorimotor and basal ganglia deficits associated with stuttering with high temporal precision. Novel findings from a non-word repetition (working memory) task are also included. They show reduced mu-alpha suppression in a stuttering group compared to a typically fluent group. Finally, we review current limitations and directions for future research.

Temperament, Executive Functioning, and Anxiety in School-Age Children Who Stutter

The purpose of this study was to examine temperament dimensions, executive functioning ability, and anxiety levels in school-age children who stutter and their non-stuttering peers. Participants were 100 Portuguese children aged 7 to 12 years (M = 9.13; SD = 1.70), including 50 children who stutter and 50 children who do not stutter. Analyses, which were performed separately for younger and older participants, sought to identify correlations between key variables. Temperament was evaluated through a parent questionnaire, executive functioning was evaluated through children’s responses on a performance test, and anxiety level was assessed through a self-perception scale. On the temperament measure, comparisons between children who stutter and their non-stuttering peers revealed that older children who stutter exhibited significantly higher scores on the Anger/Frustration, Impulsivity, and Sadness subscales, and lower averages on the Attention/Focusing, Perceptual sensitivity, and Soothability/Falling Reactivity subscales. On the executive functioning task, comparisons revealed that the group of younger children who stutter exhibited significantly higher average execution times than their non-stuttering peers. There were no statistically significant differences in anxiety between children who stutter and children who do not stutter, and there were no statistically significant correlations between temperament factors and measures of executive functioning. Children who stutter experienced lower ability to orient attention and greater emotional reactivity compared with their non-stuttering peers. Significant correlations were found between executive functioning and age and among the temperament factors themselves. These results, which support the need for a multidimensional view of stuttering, were interpreted in the context of the Dual Diathesis – Stressor model. Findings indicate that temperament and executive functioning abilities may contribute to the development of stuttering.

Effects of different attention tasks on concurrent speech in adults who stutter and fluent controls

PURPOSE

Motor theories indicate that focusing attention on well-practiced movements interferes with skilled performance; however, specific forms of attention (alerting vs. orienting vs. executive control) associated with this effect are not well understood. The present study explored this question in relation to stuttering, and examined whether dual task conditions that engaged sustained attention or working memory (WM) affected speech fluency in different ways. We also considered whether fluency changes were associated with changes in speech rate and language.

METHODS

Nineteen adults who stutter (AWS) and 20 controls produced spontaneous speech under a baseline condition and two dual task conditions: one involving a sustained attention task, the other involving WM demands.

RESULTS

Both groups produced fewer stutter-like disfluencies under dual task relative to baseline conditions and this reduction did not differ between the two dual tasks (attention vs. WM). Speech rate and language variables, which were potentially influenced by attention conditions, were not affected by dual tasks in the same way as disfluencies, and appeared to be unassociated with fluency results.

CONCLUSIONS

Findings indicate that atypical disfluencies decrease when attention is divided, even when secondary task demands are minimal, as they were in the sustained attention task. For simple secondary tasks, fluency changes do not appear to be a byproduct of slowed rate and are not accompanied by observable changes in language. These results demonstrate that simple manipulations of attention can induce measurable effects on aspects of speech production, and may be a useful tool for facilitating fluency in clinical intervention.

The Role of Executive Function in Developmental Stuttering

Developmental stuttering is a complex disorder and children who stutter form a heterogeneous group. Most contemporary researchers would agree that multiple factors, including those associated with linguistic, motor, sensory, and emotional processes, are likely involved in its development and/or maintenance. There is growing evidence, however, that cognitive processes also play a role. In this article, we briefly review behavioral and parent-report studies of executive function in children who stutter, the findings of which have generally suggested that these skills may be challenging for at least some children who stutter. We then consider how deficits in executive function could provide an explanatory account for not only the multifactorial nature of developmental stuttering but also the considerable amount of variability that exists among individuals who stutter.