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.

A Probe Study on Vocal Development in Two Infants at Risk for Cerebral Palsy.

The present work examined canonical babbling ratios longitudinally as a measure of onset and consolidation of canonical babbling in two infants at risk of cerebral palsy (CP) between 5 and 16 months. Ten typically developing infants were included for comparison at 6, 9, 12, and 16-19 months. Canonical babbling ratios (CBRs) were calculated from 5-min segments, and follow-up diagnostic outcomes were collected between 24 and 33 months. The two infants at risk demonstrated low CBR growth trajectories compared to the typical infant group, and slightly different patterns of consolidation. The two infants at risk were later diagnosed with different levels of CP and speech impairment severity. All infants demonstrated greater variability than expected. Studying canonical babbling and other prelinguistic milestones in this population may inform our perspective of the involvement of the motor system in the vocal domain. Additional implications on the analysis of canonical babbling using all-day home recordings are discussed.

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.

Word-Final Disfluencies in a School-Age Child: Beneath the Tip of the Iceberg.

Purpose Disfluencies associated with stuttering generally occur in the initial position of words. This study reviews data from a school-age child with an atypical stuttering profile consisting predominantly of word-final disfluencies (WFDs). Our primary goals were to identify patterns in overt features of WFDs and to extend our understanding of this clinical profile by focusing on aspects of stuttering that lie beneath the surface. Method Analyses explored the patterns and distributions of the child's observable stuttering behaviors, in addition to his awareness, perceptions, and subjective experience of stuttering. Results Findings indicated that the WFD profile consists of relatively consistent and distinct overt features. We also found that, in many ways, the child perceived the impact of his disfluencies much like other children who stutter, even though his disfluencies manifested in a less common form. Conclusion Findings suggest the need for increased awareness of the varied forms stuttering may take in order to ensure accurate diagnosis, clear communication to clients and parents, and timely access to appropriate intervention.

Development of a State-Wide IPE Faculty Toolkit.

Developing effective interprofessional education (IPE) training activities can be challenging, and faculty at individual programs and schools often take on this task independently. In doing so, similar ideas are frequently recreated for implementation at multiple institutions, and considerable time may be spent in these duplicative efforts. This paper describes a new state-wide effort in Tennessee to compile classroom-based IPE curricular resources and activities being used across the state in order to reduce redundancy, increase efficiency and effectiveness, and ultimately improve training outcomes for students entering health-related professions. We focus on processes involved in developing this contribution to IPE education in order to emphasize feasibility and encourage similar initiatives in other regions.

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.

The Speaker's Experience of Stuttering: Measuring Spontaneity.

Purpose This study measures the experience of spontaneous speech in everyday speaking situations. Spontaneity of speech is a novel concept developed to account for the subjective experience of speaking. Spontaneous speech is characterized by little premeditation and effortless production, and it is enjoyable and meaningful. Attention is not directed on the physical production of speech. Spontaneity is intended to be distinct from fluency so that it can be used to describe both stuttered and fluent speech. This is the first study to attempt to measure the concept of spontaneity of speech. Method The experience sampling method was used with 44 people who stutter. They were surveyed five times a day for 1 week through their cell phones. They reported on their perceived spontaneity, fluency, and speaking context. Results Results indicate that spontaneity and fluency are independent, though correlated, constructs that vary with context. Importantly, an increase in spontaneity significantly decreases the adverse impact of stuttering on people's lives. Fluency did not significantly affect adverse life impact of stuttering. Conclusion Findings support a theoretical construct of spontaneity that is distinct from speech fluency and that can inform our views of stuttering and approaches to stuttering treatment.

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.

Cognitive flexibility in preschool children with and without stuttering disorders.

PURPOSE: Multifactorial explanations of developmental stuttering suggest that difficulties in self-regulation and weak attentional flexibility contribute to persisting stuttering. We tested this prediction by examining whether preschool-age children who stutter (CWS) shift their attention less flexibly than children who do not stutter (CWNS) during a modified version of the Dimension Card Change Sort (DCCS), a reliable measure of attention switching for young children. METHODS: Sixteen CWS (12 males) and 30 children CWNS (11 males) participated in the study. Groups were matched on age (CWS: M=49.63, SD=10.34, range=38-80months; CWNS: M=50.63, SD=9.82, range=37-74months), cognitive ability, and language skills. All children completed a computer-based variation of the DCCS, in which they matched on-screen bivalent stimuli to response buttons based on rules that switched mid-task. RESULTS: Results showed increased slowing for CWS compared to controls during the postswitch phase, as well as contrasting patterns of speed-accuracy tradeoff for CWS and CWNS as they moved from the preswitch to postswitch phase of the task. CONCLUSIONS: Group differences in performance suggest that early stuttering may be associated with difficulty shifting attention efficiently and greater concern about errors. Findings are consistent with a growing literature indicating links between weak attentional control and persisting developmental stuttering.

Does Working Memory Enhance or Interfere With Speech Fluency in Adults Who Do and Do Not Stutter? Evidence From a Dual-Task Paradigm.

PURPOSE: The present study examined whether engaging working memory in a secondary task benefits speech fluency. Effects of dual-task conditions on speech fluency, rate, and errors were examined with respect to predictions derived from three related theoretical accounts of disfluencies. METHOD: Nineteen adults who stutter and twenty adults who do not stutter participated in the study. All participants completed 2 baseline tasks: a continuous-speaking task and a working-memory (WM) task involving manipulations of domain, load, and interstimulus interval. In the dual-task portion of the experiment, participants simultaneously performed the speaking task with each unique combination of WM conditions. RESULTS: All speakers showed similar fluency benefits and decrements in WM accuracy as a result of dual-task conditions. Fluency effects were specific to atypical forms of disfluency and were comparable across WM-task manipulations. Changes in fluency were accompanied by reductions in speaking rate but not by corresponding changes in overt errors. CONCLUSIONS: Findings suggest that WM contributes to disfluencies regardless of stuttering status and that engaging WM resources while speaking enhances fluency. Further research is needed to verify the cognitive mechanism involved in this effect and to determine how these findings can best inform clinical intervention.

The effect of plausibility on sentence comprehension among older adults and its relation to cognitive functions.

UNLABELLED: BACKGROUND/STUDY CONTEXT: Older adults show age-related decline in complex-sentence comprehension. This has been attributed to a decrease in cognitive abilities that may support language processing, such as working memory (e.g., Caplan, DeDe, Waters, & Michaud, 2011,Psychology and Aging, 26, 439-450). The authors examined whether older adults have difficulty comprehending semantically implausible sentences and whether specific executive functions contribute to their comprehension performance. METHODS: Forty-two younger adults (aged 18-35) and 42 older adults (aged 55-75) were tested on two experimental tasks: a multiple negative comprehension task and an information processing battery. RESULTS: Both groups, older and younger adults, showed poorer performance for implausible sentences than for plausible sentences; however, no interaction was found between plausibility and age group. A regression analysis revealed that inhibition efficiency, as measured by a task that required resistance to proactive interference, predicted comprehension of implausible sentences in older adults only. Consistent with the compensation hypothesis, the older adults with better inhibition skills showed better comprehension than those with poor inhibition skills. CONCLUSION: The findings suggest that semantic implausibility, along with syntactic complexity, increases linguistic and cognitive processing loads on auditory sentence comprehension. Moreover, the contribution of inhibitory control to the processing of semantic plausibility, particularly among older adults, suggests that the relationship between cognitive ability and language comprehension is strongly influenced by age.

Verbal strategies and nonverbal cues in school-age children with and without specific language impairment (SLI).

BACKGROUND: Considerable evidence suggests that performance across a variety of cognitive tasks is effectively supported by the use of verbal and nonverbal strategies. Studies exploring the usefulness of such strategies in children with specific language impairment (SLI) are scarce and report inconsistent findings. AIMS: To examine the effects of induced labelling and auditory cues on the performance of children with and without SLI during a categorization task. METHODS & PROCEDURES: Sixty-six school-age children (22 with SLI, 22 age-matched controls, 22 language-matched controls) completed three versions of a computer-based categorization task: one baseline, one requiring overt labelling and one with auditory cues (tones) on randomized trial blocks. OUTCOMES & RESULTS: Labelling had no effect on performance for typically developing children but resulted in lower accuracy and longer reaction time in children with SLI. The presence of tones had no effect on accuracy but resulted in faster reaction time and post-error slowing across groups. CONCLUSIONS & IMPLICATIONS: Verbal strategy use was ineffective for typically developing children and negatively affected children with SLI. All children showed faster performance and increased performance monitoring as a result of tones. Overall, effects of strategy use in children appear to vary based on task demands, strategy domain, age and language ability. Results suggest that children with SLI may benefit from auditory cues in their clinical intervention but that further research is needed to determine when and how verbal strategies might similarly support performance in this population.

Information processing and proactive interference in children with and without specific language impairment.

PURPOSE: Increasing evidence suggests that children with specific language impairment (SLI) have a deficit in inhibition control, but research isolating specific abilities is scarce. The goal of this study was to examine whether children with SLI differ from their peers in resistance to proactive interference under different conditions. METHOD: An information processing battery with manipulations in interference was administered to 66 children (SLI, age matched peers, and language-matched controls). In Experiment 1, previously relevant targets were used as distractors to create conflict. Experiment 2 used item repetitions to examine how practice strengthens word representations and how the strength of a response impacts performance on the following item. RESULTS: Children with SLI performed similarly to their peers in the baseline condition but were more susceptible to proactive interference than the controls in both experimental conditions. Children with SLI demonstrated difficulty suppressing irrelevant information, made significantly more interference errors than their peers, and showed a slower rate of implicit learning. CONCLUSION: Children with SLI show weaker resistance to proactive interference than their peers, and this deficit impacts their information processing abilities. The coordination of activation and inhibition is less efficient in these children, but future research is needed to further examine the interaction between these two processes.

EXECUTIVE FUNCTION PROFILES IN CHILDREN WITH AND WITHOUT SPECIFIC LANGUAGE IMPAIRMENT.

We present findings from a study that focused on specific executive functions (EF) in children with and without specific language impairment (SLI). We analyzed performance patterns and EF profiles (spatial working memory, inhibition control, and sustained attention) in school-age SLI children and two control groups: age-matched and language matched. Our main research goal was to identify those EFs that show a weakness in children with SLI. Our specific aims were to: (1) examine whether the EF problems in children with SLI are domain-general; (2) examine whether deficits in EF in children with SLI can be explained by the general slowness hypothesis or by an overall delay in development; (3) compare EF profiles to examine whether children with SLI show a distinct pattern of performance from their peers. Our findings showed different EF profiles for the groups. We observed differences in performance patterns related to age (e.g., reaction time in response inhibition) and differences related to language status (e.g., sensitivity to interference). The findings show interesting associations in EFs that play a crucial role in language processing.

A meta-analysis of outcomes of hydration intervention on phonation threshold pressure.

OBJECTIVES: Vocal fold hydration is purported to promote optimal biomechanical characteristics of vocal fold mucosa, increase efficiency of vocal fold oscillation, and enhance voice quality. The purpose of this work was to determine the magnitude and consistency of the effect of vocal fold hydration on vocal fold function across published clinical studies. METHODS: We completed a comprehensive meta-analysis of the effects of superficial and systemic vocal fold hydration on phonation threshold pressure (PTP), a measure of efficiency of voice production. RESULTS: We identified 34 studies that examined the effects of hydration on vocal function. Of these studies, 14 examined the effects of hydration on PTP. Nine of these articles met the criteria for inclusion in this analysis. We observed an average effect size of 0.33, indicating that, overall, hydration treatment demonstrated a tendency to reduce PTP. However, this decrease in phonatory effort did not reach significance at the 95% confidence level. The effects of hydration intervention varied considerably across studies (-0.19 to 3.96). We considered that two factors, pitch level of the task and vocal health of participants, may have contributed to this variability in findings. However, our analysis found that these factors could not account for differences in effect size. CONCLUSION: To understand the variability in outcomes across studies, the role of factors that may impact the effects of hydration, such as the amount, type, and duration of intervention, must be determined. Only then can we obtain data to guide best clinical practice for protecting and rehabilitating vocal function.