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.

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.

Enhancing long-term weight loss maintenance: 2 year results from the Keep It Off randomized controlled trial.

OBJECTIVE: The Keep It Off trial evaluated the efficacy of a phone-based weight loss maintenance intervention among adults who had recently lost weight in Minnesota (2007-2010). METHODS: 419 adults who had recently lost ≥ 10% of their body weight were randomized to the "Guided" or "Self-Directed" intervention. Guided participants received a 10 session workbook, 10 biweekly, eight monthly and six bimonthly phone coaching calls, bimonthly weight graphs and tailored letters based on self-reported weights. Self-Directed participants received the workbook and two calls. Primary outcomes are weight change and maintenance (regain of <2.5% of baseline body weight). RESULTS: Mixed model repeated-measures analysis examining weight change revealed a significant time by treatment group interaction (p<0.0085). Guided participants regained significantly less weight than the Self-Directed participants at 12 and 24 months. The odds of 24 month maintenance were 1.37 (95% CI: 0.97-2.03) times greater in the Guided than in the Self-Directed group. When maintenance rates were compared across all follow-ups, there was a consistently higher maintenance rate for Guided participants (HR 1.31, 95% CI: 1.12-1.54). CONCLUSIONS: A sustained, supportive phone- and mail-based intervention promotes weight loss maintenance relative to a brief intervention for participants who have recently lost weight.

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.

A comparison of the performance of Persian speaking children who do and do not stutter on three nonwords repetition tasks.

PURPOSE: The purpose of the study was to examine the performance of Persian speaking children who stutter (CWS) and children who do not stutter (CWNS) on three nonword repetition tasks, while also focusing on which task and scoring method best differentiates the two groups of children. METHOD: Thirty CWS and 30 CWNS between the ages of 5;0 to 6;6 completed three nonword repetition tasks that varied in complexity. Each task was scored using two methods: nonwords correct and phonemes correct. Between-group differences in performance on each task were examined, along with disfluencies for CWS and the task and scoring method that best differentiated the CWS and CWNS. RESULTS: The findings revealed that, across all three nonword repetition tasks, the CWS consistently produced fewer nonwords correct and phonemes correct than the CWNS group at virtually all syllable lengths. The CWS produced more disfluencies on longer nonwords than shorter nonwords in all three nonword repetition tasks. The nonword repetition task with lower wordlikeness and more phonologically complex items best differentiated the two groups of children. Findings further revealed that discriminative accuracy was highest for scoring based on the number of phonemes produced correctly. CONCLUSION: Findings provide further evidence to suggest that CWS may have difficulty with phonological working memory and/or phonological processing.

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.

Visual exogenous and endogenous attention and visual memory in preschool children who stutter.

PURPOSE: Attention develops gradually from infancy to the preschool years and beyond. Exogenous attention, consisting of automatic responses to salient stimuli, develops in infancy, whereas endogenous attention, or voluntary attention, begins to develop later, in the preschool years. The purpose of this study was to examine (a) exogenous and endogenous attention in young children who stutter (CWS) and children who do not stutter (CWNS) through two conditions of a visual sustained selective attention task, and (b) visual short-term memory (STM) between groups within the context of this task. METHOD: 42 CWS and 42 CWNS, ages 3;0-5;5 (years;months), were pair-matched in age, gender (31 males, 11 females per group), and socioeconomic status. Children completed a visual tracking task (Track-It Task; Fisher et al., 2013) requiring sustained selective attention and engaging exogenous and endogenous processes. Following each item, children were asked to recall the item they had tracked, as a memory check. RESULTS: The CWS group demonstrated significantly less accuracy in overall tracking and visual memory for the tracked stimuli, compared to the CWNS group. Across groups, the children performed better in sustained selective attention when the target stimuli were more salient (the condition tapping both exogenous and endogenous attention) than when stimuli were less so (the condition tapping primarily endogenous processes). CONCLUSIONS: Relative to peers, preschool-age CWS, as a group, display weaknesses in visual sustained selective attention and visual STM.

Phonological and Semantic Contributions to Verbal Short-Term Memory in Young Children With Developmental Stuttering.

Purpose The purpose of this study was to examine the verbal short-term memory skills of children who stutter (CWS) and children who do not stutter (CWNS) in 2 experiments, focusing on the influence of phonological and semantic similarity. Method Participants were 42 CWS and 42 CWNS between the ages of 3;0 and 5;11 (years;months). In Experiment 1, children completed the phonological similarity task, in which they listened to lists of phonologically similar and dissimilar words and then repeated them when signaled to do so. In Experiment 2, children completed another forward span task, the semantic category task, which is similar to the phonological similarity task, except that it consisted of lists of semantically homogeneous and heterogeneous words. Main dependent variables were cumulative memory span, proportion of errors by type, and speech reaction time (SRT) for correct responses. Results The CWS exhibited significantly shorter memory spans for phonologically dissimilar words and were less affected by the phonological qualities of the words than the CWNS in Experiment 1, based on the findings of both between-groups and within-group analyses. In Experiment 2, although the groups did not differ in their performance in either condition, within-group analyses revealed that the CWNS benefitted from semantic similarity, whereas the CWS did not. The between-groups difference in absolute difference scores, however, did not reach significance. The CWS produced more omissions and false alarms than the CWNS in both experiments, but the 2 groups of children were otherwise comparable in SRT, although the CWS exhibited overall faster SRT than the CWNS in Experiment 2. Conclusions Verbal short-term memory is one domain-general cognitive process in which CWS display weakness relative to typically fluent peers. These weaknesses are likely due, in part, to differences in phonological and, perhaps, semantic processing of words to aid memory.

Phonotactic probability effects in children who stutter.

PURPOSE: The purpose of this study was to examine the influence of phonotactic probability, which is the frequency of different sound segments and segment sequences, on the overall fluency with which words are produced by preschool children who stutter (CWS) as well as to determine whether it has an effect on the type of stuttered disfluency produced. METHOD: A 500+ word language sample was obtained from 19 CWS. Each stuttered word was randomly paired with a fluently produced word that closely matched it in grammatical class, word length, familiarity, word and neighborhood frequency, and neighborhood density. Phonotactic probability values were obtained for the stuttered and fluent words from an online database. RESULTS: Phonotactic probability did not have a significant influence on the overall susceptibility of words to stuttering, but it did impact the type of stuttered disfluency produced. In specific, single-syllable word repetitions were significantly lower in phonotactic probability than fluently produced words, part-word repetitions, and sound prolongations. CONCLUSIONS: In general, the differential impact of phonotactic probability on the type of stuttering-like disfluency produced by young CWS provides some support for the notion that different disfluency types may originate in the disruption of different levels of processing.

Executive function and childhood stuttering: Parent ratings and evidence from a behavioral task.

PURPOSE: The purpose of this study was to examine the executive function (EF) abilities of preschool children who do (CWS) and do not stutter (CWNS) using a parent-report questionnaire and a behavioral task. METHOD: Participants were 75 CWS and 75 CWNS between the ages of 3;0 and 5;11 (years; months). Parents rated their children's EF abilities using the Behavioral Rating Inventory of Executive Function-Preschool Version (BRIEF-P; Gioia, Espy, & Isquith, 2003). Children's ability to integrate cognitive flexibility, inhibitory control, and working memory was measured using a behavioral task, the Head-Toes-Knees-Shoulders (HTKS; Cameron Ponitz, McClelland, Matthews, & Morrison, 2009). RESULTS: The CWS were judged by their parents as being less proficient in working memory, shift/flexibility, and overall EF than the parents of the CWNS. Children in the CWS group were also 2½ to 7 times more likely than children in the CWNS group to exhibit clinically significant difficulties with EF. Behavioral task findings revealed that 3-year old CWS performed more poorly than their peers on the HTKS. Parental ratings of executive function and working memory were significantly and moderately correlated with receptive and expressive vocabulary skills only for the CWNS group. CONCLUSION: CWS have more difficulty with EF in everyday life and may experience early delays in their ability to integrate aspects of attention and EF compared to CWNS.

Short-Term Memory, Inhibition, and Attention in Developmental Stuttering: A Meta-Analysis.

Purpose: This study presents a meta-analytic review of differences in verbal short-term memory, inhibition, and attention between children who stutter (CWS) and children who do not stutter (CWNS). Method: Electronic databases and reference sections of articles were searched for candidate studies that examined verbal short-term memory, inhibition, and attention using behavioral and/or parent report measures. Twenty-nine studies met the eligibility criteria, which included, among other things, children between the ages of 3 and 18 years and the availability of quantitative data for effect size calculations. Data were extracted, coded, and analyzed, with the magnitude of the difference between the 2 groups of children being estimated using Hedge's g (Hedges & Olkin, 1985). Results: Based on the random-effects model (Hunter & Schmidt, 2004), findings revealed that CWS scored lower than CWNS on measures of nonword repetition (Hedges' g = -0.62), particularly at lengths of 2 and 3 syllables (Hedges' g = -0.62 and - 0.50, respectively), and forward span (Hedges' g = -0.40). Analyses further revealed that the parents of CWS rated their children as having weaker inhibition (Hedges' g = -0.44) and attentional focus/persistence (Hedges' g = -0.36) skills than the parents of CWNS, but there were no significant differences between CWS and CWNS in behavioral measures of inhibition and attention. Conclusion: The present findings were taken to suggest that cognitive processes are important variables associated with developmental stuttering.

Phonological neighborhood and word frequency effects in the stuttered disfluencies of children who stutter.

PURPOSE: The purpose of this study was to examine (a) the role of neighborhood density (number of words that are phonologically similar to a target word) and frequency variables on the stuttering-like disfluencies of preschool children who stutter, and (b) whether these variables have an effect on the type of stuttering-like disfluency produced. METHOD: A 500+ word speech sample was obtained from each participant (N = 15). Each stuttered word was randomly paired with the firstly produced word that closely matched it in grammatical class, familiarity, and number of syllables/phonemes. Frequency, neighborhood density, and neighborhood frequency values were obtained for the stuttered and fluent words from an online database. RESULTS: Findings revealed that stuttered words were lower in frequency and neighborhood frequency than fluent words. Words containing part-word repetitions and sound prolongations were also lower in frequency and/or neighborhood frequency than fluent words, but these frequency variables did not have an effect on single-syllable word repetitions. Neighborhood density failed to influence the susceptibility of words to stuttering, as well as the type of stuttering-like disfluency produced. CONCLUSIONS: In general, findings suggest that neighborhood and frequency variables not only influence the fluency with which words are produced in speech, but also have an impact on the type of stuttering-like disfluency produced.

Explicit and Implicit Verbal Response Inhibition in Preschool-Age Children Who Stutter.

Purpose: The purpose of this study was to examine (a) explicit and implicit verbal response inhibition in preschool children who do stutter (CWS) and do not stutter (CWNS) and (b) the relationship between response inhibition and language skills. Method: Participants were 41 CWS and 41 CWNS between the ages of 3;1 and 6;1 (years;months). Explicit verbal response inhibition was measured using a computerized version of the grass-snow task (Carlson & Moses, 2001), and implicit verbal response inhibition was measured using the baa-meow task. Main dependent variables were reaction time and accuracy. Results: The CWS were significantly less accurate than the CWNS on the implicit task, but not the explicit task. The CWS also exhibited slower reaction times than the CWNS on both tasks. Between-group differences in performance could not be attributed to working memory demands. Overall, children's performance on the inhibition tasks corresponded with parents' perceptions of their children's inhibition skills in daily life. Conclusions: CWS are less effective and efficient than CWNS in suppressing a dominant response while executing a conflicting response in the verbal domain.

Nonword repetition skills in young children who do and do not stutter.

UNLABELLED: The purpose of this study was to assess the nonword repetition skills of 24 children who do (CWS; n = 12) and do not stutter (CWNS; n = 12) between the ages of 3;0 and 5;2. Findings revealed that CWS produced significantly fewer correct two- and three-syllable nonword repetitions and made significantly more phoneme errors on three-syllable nonwords relative to CWNS. In addition, there was a significant relationship between performance on a test of expressive phonology and nonword repetition for CWS, but not CWNS. Findings further revealed no significant fluctuation in fluency as nonwords increased in length. Taken together, findings lend support to previous work, suggesting that nonword repetition skills differ for CWS compared with CWNS, and that these findings cannot be attributed to (a) weak language performance on the part of CWS, or (b) the occurrence of stuttering in the course of nonword production. EDUCATIONAL OBJECTIVES: After reading this article, the learner will be able to: (a) describe one common means of assessing phonological working memory in children; (b) summarize the performance differences of children who stutter compared to peers on a nonword repetition task; (c) compare the results of the present study with previous work in this area.

Childhood stuttering and dissociations across linguistic domains.

UNLABELLED: The purpose of this investigation was to evaluate the possible presence of dissociations in the speech and language skills of young children who do (CWS) and do not stutter (CWNS) using a correlation-based statistical procedure [Bates, E., Appelbaum, M., Salcedo, J., Saygin, A. P., & Pizzamiglio, L. (2003). Quantifying dissociations in neuropsychological research. Journal of Clinical and Experimental Neuropsychology, 25, 1128-1153]. Participants were 45 preschool CWS and 45 CWNS between the ages of 3;0 and 5;11 (years;months), with the two groups matched by age, gender, race, and parental socioeconomic status. Children participated in a parent-child interaction for the purpose of disfluency analysis and responded to four standardized speech-language tests for subsequent analyses as main dependent variables. Findings indicated that CWS were over three times more likely than CWNS to exhibit dissociations across speech-language domains, with 44 cases of dissociation for CWS and 14 for CWNS across 10 possible comparisons. Results suggest that there may be a subgroup of CWS who exhibit dissociations across speech-language domains, which may result in a greater susceptibility to breakdowns in speech fluency. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) summarize findings from previous studies examining differences in speech and language performance between children who do and do not stutter; (2) describe what is meant by "dissociations" in the speech and language skills of young children who do and do not stutter; and (3) discuss three hypotheses that could account for the present findings that suggest CWS, more often than CWNS, exhibit dissociations in their speech-language system.

Pediatric Primary Care-Based Obesity Prevention for Parents of Preschool Children: A Pilot Study.

BACKGROUND: The Healthy Homes/Healthy Kids Preschool (HHHK-Preschool) pilot program is an obesity prevention intervention integrating pediatric care provider counseling and a phone-based program to prevent unhealthy weight gain among 2- to 4-year-old children at risk for obesity (BMI percentile between the 50th and 85th percentile and at least one overweight parent) or currently overweight (85th percentile ≤ BMI < 95th percentile). The aim of this randomized, controlled pilot study was to evaluate the feasibility, acceptability, and potential efficacy of the HHHK-Preschool intervention. METHODS: Sixty parent-child dyads recruited from pediatric primary care clinics were randomized to: (1) the Busy Bodies/Better Bites Obesity Prevention Arm or the (2) Healthy Tots/Safe Spots safety/injury prevention Contact Control Arm. Baseline and 6-month data were collected, including measured height and weight, accelerometry, previous day dietary recalls, and parent surveys. Intervention process data (e.g., call completion) were also collected. RESULTS: High intervention completion and satisfaction rates were observed. Although a statistically significant time by treatment interaction was not observed for BMI percentile or BMI z-score, post-hoc examination of baseline weight status as a moderator of treatment outcome showed that the Busy Bodies/Better Bites obesity prevention intervention appeared to be effective among children who were in the overweight category at baseline relative to those who were categorized as at risk for obesity (p = 0.04). CONCLUSIONS: HHHK-Preschool pilot study results support the feasibility, acceptability, and potential efficacy in already overweight children of a pediatric primary care-based obesity prevention intervention integrating brief provider counseling and parent-targeted phone coaching. What's New: Implementing pediatric primary care-based obesity interventions is challenging. Previous interventions have primarily involved in-person sessions, a barrier to sustained parent involvement. HHHK-preschool pilot study results suggest that integrating brief provider counseling and parent-targeted phone coaching is a promising approach.

Activity Patterns of Preschool-Aged Children at Risk for Obesity.

BACKGROUND: Although the prevalence of obesity in young children highlights the importance of early interventions to promote physical activity (PA), there are limited data on activity patterns in this age group. The purpose of this study was to describe activity patterns in preschool-aged children and explore differences by weight status. METHODS: Analyses use baseline data from Healthy Homes/Healthy Kids-Preschool, a pilot obesity prevention trial of preschool-aged children who are overweight or at risk for being overweight. A modified parent-reported version of the previous-day PA recall was used to summarize types of activity. Accelerometry was used to summarize daily and hourly activity patterns. RESULTS: "Playing with toys" accounted for the largest proportion of a child's previous day, followed by "meals and snacks" and "chores." Accelerometry-measured daily time spent in sedentary behavior, light PA, and moderate-to-vigorous PA (MVPA) was 412, 247, and 69 minutes, respectively. Percentage of hourly time spent in MVPA ranged from 3% to 13%, peaking in the late morning and evening hours. There were no statistically significant MVPA differences by weight status. CONCLUSIONS: This study extends our understanding of activity types, amounts, and patterns in preschool-aged children and warrants further exploration of differences in PA patterns by weight status.

Sentence-structure priming in young children who do and do not stutter.

The purpose of this study was to use an age-appropriate version of the sentence-structure priming paradigm (e.g., K. Bock, 1990; K. Bock, H. Loebell, and R. Morey, 1992) to assess experimentally the syntactic processing abilities of children who stutter (CWS) and children who do not stutter (CWNS). Participants were 16 CWS and 16 CWNS between the ages of 3;3 (years; months) and 5;5, matched for gender and age (+/-4 months). All participants had speech, language, and hearing development within normal limits, with the exception of stuttering for CWS. All children participated in a sentence-structure priming task where they were shown and asked to describe, on a computer screen, black-on-white line drawings of children, adults, and animals performing activities that could be appropriately described using simple active affirmative declarative (SAAD) sentences (e.g., "The man is walking the dog"). Speech reaction time (SRT) was measured from the onset of the picture presentation to the onset of the child's verbal response in the absence and presence of priming sentences, counterbalanced for order. Main findings indicated that CWS exhibited slower SRTs in the absence of priming sentences and greater syntactic-priming effects than CWNS. These findings suggest that CWS may have difficulty rapidly, efficiently planning and/or retrieving sentence-structure units, difficulties that may contribute to their inabilities to establish fluent speech-language production.

Temperamental characteristics of young children who stutter.

The purpose of this investigation was to assess the temperamental characteristics of children who do (CWS) and do not (CWNS) stutter using a norm-referenced parent-report questionnaire. Participants were 31 CWS and 31 CWNS between the ages of 3;0 (years;months) and 5;4 (CWS: mean age = 48.03 months; CWNS: mean age = 48.58 months). The CWS were matched by age (+/- 4 months), gender, and race to the CWNS. All participants had speech, language, and hearing development within normal limits, with the obvious exception of stuttering for CWS. Children's temperamental characteristics were determined using the Behavioral Style Questionnaire (BSQ; S. C. McDevitt & W. B. Carey, 1978), which was completed by each child's parents. Results, based on parent responses to the BSQ, indicated that CWS are more apt, when compared to CWNS, to exhibit temperamental profiles consistent with hypervigilance (i.e., less distractibility), nonadaptability to change, and irregular biological functions. Findings suggest that some temperamental characteristics differentiate CWS from CWNS and could conceivably contribute to the exacerbation, as well as maintenance, of their stuttering.

Healthy Homes/Healthy Kids: a randomized trial of a pediatric primary care-based obesity prevention intervention for at-risk 5-10 year olds.

Pediatric primary care is an important setting in which to address obesity prevention, yet relatively few interventions have been evaluated and even fewer have been shown to be effective. The development and evaluation of cost-effective approaches to obesity prevention that leverage opportunities of direct access to families in the pediatric primary care setting, overcome barriers to implementation in busy practice settings, and facilitate sustained involvement of parents is an important public health priority. The goal of the Healthy Homes/Healthy Kids (HHHK 5-10) randomized controlled trial is to evaluate the efficacy of a relatively low-cost primary care-based obesity prevention intervention aimed at 5 to 10 year old children who are at risk for obesity. Four hundred twenty one parent/child dyads were recruited and randomized to either the obesity prevention arm or a Contact Control condition that focuses on safety and injury prevention. The HHHK 5-10 obesity prevention intervention combines brief counseling with a pediatric primary care provider during routine well child visits and follow-up telephone coaching that supports parents in making home environmental changes to support healthful eating, activity patterns, and body weight. The Contact Control condition combines the same provider counseling with telephone coaching focused on safety and injury prevention messages. This manuscript describes the study design and baseline characteristics of participants enrolled in the HHHK 5-10 trial.