Atypical gut microbiota composition in a mouse model of developmental stuttering.

Developmental stuttering is a complex neurodevelopmental disorder characterized by disfluent speech. It has been associated with mutations in genes involved in lysosomal enzyme trafficking. Mice with mutations in one such gene, Gnptab, exhibit atypical vocalizations analogous to stuttering in humans. This mouse model has enabled the study of various molecular mechanisms related to the disorder. Simultaneously, an increasing number of reports have suggested the role of gut microbiota in altered brain function and development in neurological disorders. In this study, we compared gut microbiota profiles from Gnptab mutant mice to wildtype control mice. Microbiome analysis demonstrated a distinct microbiota profile in Gnptab mutant mice. The most significant alteration was an increased relative abundance of Akkermansia, a genus of mucin degrading bacteria, which has previously been associated with multiple neurological disorders. Moreover, the altered microbiota profile of these mice was predicted to result in differences in abundance of several metabolic pathways, including short chain fatty acid and lipopolysaccharide synthesis. These pathways may play a role in the onset, progression and persistence of developmental stuttering. This is the first study to show a potential link between developmental stuttering and changes in the gut microbiota, laying the groundwork for a new research direction.

Developmental stuttering in adults.

Developmental stuttering is characterized by early childhood onset with repetition of syllables, prolongations, and blockades as well as secondary behavioural abnormalities. Early therapy is important while there is no approved pharmacological approach. Studies associate developmental stuttering with dopamin surplus in the striatum causing dysfunction of cortical speech areas. Consequently, antidopaminergic agents are being investigated to improve symptoms. The evidence in adults is comprised of few studies of poor quality but might hold promise as a new treatment option, as argued in this review.

Evaluating Stuttering Self-Stigma and Its Relationship to Adverse Impact in Children and Adolescents With the Child Stuttering Self-Stigma Scale.

PURPOSE: Self-stigma occurs when a person internalizes and applies stereotypes, prejudice, and discrimination to themselves. For adults who stutter, self-stigma is linked to negative outcomes and reduced quality of life. The development of self-stigma in people who stutter is not well understood. The aim of this study is to evaluate stuttering self-stigma in school-age children and adolescents and explore potential relationships to stuttering's overall adverse impact. METHOD: One hundred one children and adolescents who stutter, aged 10-18 years, completed the Overall Assessment of the Speaker's Experience of Stuttering (OASES), a measure of adverse impact related to stuttering, and the Childhood Self-Stigma of Stuttering Scale (Child 4S), our novel adapted version of the Self-Stigma of Stuttering Scale (4S) created for this study. The Child 4S comprises three subscales measuring three stages of self-stigma: Awareness, Agreement, and Application. Each stage was evaluated for relationships with child age and the adverse impact of stuttering. RESULTS: We found a range of self-stigma scores among children and adolescents who stutter. Child age did not correlate with Awareness and Agreement; however, older children and adolescents reported greater Application. All stages of self-stigma strongly predicted adverse impact as measured by the OASES, and latter stages of the model were stronger predictors than earlier stages. CONCLUSIONS: Children as young as 10 years old may experience stuttering self-stigma, and the application of self-stigma increases in adolescence, a critical period in the development of personal identity. Importantly, all stages of self-stigma predicted adverse impact related to stuttering, with latter stages being stronger predictors than earlier ones consistent with the progressive model of self-stigma being tested. The findings highlight the need for targeted, early intervention to mitigate downstream effects of stuttering self-stigma. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.26352556.

Perceptions of and beliefs about stuttering in the Hispanic/Latino community.

PURPOSE: The aim of this exploratory study was to investigate perceptions of people who stutter and beliefs about the causes and cures of stuttering within the Hispanic/Latino community. METHODS: Respondents who were 18 or older and of Hispanic/Latino origin were invited to respond to a 24-question online survey. Questions involved exploring familiarity with and beliefs regarding etiologies, treatment approaches, treatment providers, stereotypes, and perceptions of people who stutter. Data from 151 respondents were analyzed using descriptive statistics. RESULTS: Results revealed that the most commonly held beliefs regarding the causes of stuttering were being "born with it", an "emotional disturbance or trauma", a "brain disorder", and/ or a "sensory impairment". The most frequently cited beliefs regarding treating stuttering were "therapy", "rehabilitation", and "tell them to slow down". Over 75 % of respondents believed that "speech therapists" can cure or treat stuttering. Respondents' perceptions of people who stutter are that they are generally "nervous" and "shy". CONCLUSIONS: Common beliefs and perceptions relative to stuttering were identified in the Hispanic/Latino community. The beliefs one holds about the cause of stuttering as well as their negative perceptions of stutterers may contribute to the continued stigmatization of people who stutter. Implications are discussed regarding the need for culturally appropriate education for individuals who stutter, their families, and the general public.

Italian normative data for the Unhelpful Thoughts and Beliefs about Stuttering (UTBAS) Scales for adults who stutter.

PURPOSE: This study aimed to assess the reliability and validity of the Italian translation of the Unhelpful Thoughts and Beliefs about Stuttering (UTBAS) scales for adults who stutter, as there are no assessment tools currently available in Italy. The UTBAS scales provide a comprehensive stuttering-specific measure of the unhelpful thoughts and beliefs that can be used to screen for indicators of social anxiety in adults who stutter. Additionally, the UTBAS scales also allow the identification of negative thoughts and beliefs that negatively impact speech treatment outcomes. METHOD: The translation of the UTBAS scales into Italian (UTBAS-ITA) was completed using the forward-backward translation process and it was administered to 98 adults who stutter (AWS) and 98 adults who do not stutter (AWNS). Both groups were matched for gender and age. We also administered the UTBAS-ITA to 76 AWS a second time within a two-week interval to assess test-retest reliability. Additionally, we administered the State-Trait Anxiety Inventory and the Fear of Negative Evaluation Scale to 20 AWS to assess concurrent validity. RESULTS: The UTBAS-ITA showed good power of discrimination between AWS and AWNS, high internal validity, high internal consistency, good construct validity, and good test-retest reliability. CONCLUSION: Since there is a scarcity of clinical assessment tools for adults who stutter in Italy, the UTBAS-ITA could serve as an assessment tool and outcome measure for clinical and research environments.

Explicit and implicit cognitive processes of the public towards people who stutter.

PURPOSE: The Public Opinion Survey of Human Attributes - Stuttering (POSHA-S, St. Louis, 2013) was developed as a standard measure of public attitudes about people who stutter. As with any survey-based methods, threats to validity may occur because of social desirability bias. Using computer mouse-tracking, we were interested in observing changes in cognition that are manifested in intentionality through action by evaluating underlying cognitive processes that drive social judgments of people who stutter. METHODS: Twenty-two women, 1 non-binary person, and 47 men reported using a computer mouse to complete an online, remote, and modified version of the POSHA-S. Responses were categorized as correct/helpful or incorrect/unhelpful relative to each component of the POSHA-S and were used as measures of explicit cognitive processes. Computer-mouse trajectory metrics, including area under the curve (AUC) and reaction time (RT), were used to measure implicit cognitive processes. RESULTS: Although participants' explicit responses were significantly more likely to be correct/helpful than incorrect/unhelpful, with endorsement of correct/helpful prompts 77 % of the time, participants also endorsed incorrect/unhelpful prompts more than half (i.e., 52 %) of the time. Familiarity with people who stutter was associated with disagreeing with incorrect/unhelpful prompts. As indicated by greater AUC, participants exhibited significantly more implicit cognitive processes indicating competition when responding "disagree" compared to "agree", regardless of whether the prompts were correct/helpful or incorrect/unhelpful. Similarly, participants took significantly longer to respond to prompts with "disagree" rather than "agree". CONCLUSION: The findings of this study offer evidence of participants reporting cognitive processes that are overall more correct/helpful than incorrect/unhelpful, in their explicit responses to the dichotomous response tasks of the POSHA-S. However, these findings are tempered by evidence of a tendency to agree with statements in the measure and suggest the need for further research to increase understanding of how to measure and improve explicit and implicit cognitive processes related to people who stutter.

Mitigating stuttering self-stigma: How do we start and where do we go? Using a Participative Concept Mapping Approach to develop a local framework of principles.

PURPOSE: This study aims to create a stigma reduction framework for stuttering in the local context of Québec, Canada using the Participative Concept Mapping Approach (PCMA), focusing on both self and societal stigma. METHOD: Employing a mixed-methods approach, this study engaged 17 experts-people who stutter, clinicians and health innovation specialists-in PCMA workshops. Via diverse steps, including generation, sorting and rating of ideas in response to the focus prompt, "To effectively address stuttering (self-)stigma, an intervention should…" these sessions led to a framework depicted in visual maps, then refined into actionable principles through qualitative analysis. Mixed-methods data analysis used the open-source R-CMap software to generate visual maps illustrating the relationships among ideas as well as importance and feasibility ratings. RESULTS: The collaborative workshops identified 95 ideas in response to the focus prompt, reunited in 7 clusters, evolving into 16 principles to mitigate stuttering stigma and self-stigma. At the therapy level, these principles emphasize personalized therapy, thorough assessments, stigma-free therapeutic environment, empowerment, and the importance of group inclusivity and educating the relational circles. Societally, they advocate for initiatives such as improved educational outreach, empathy enhancement, and better representation. This dual approach targets individual experiences and societal views on stuttering, stressing the need for an all-encompassing intervention framework. CONCLUSION: The findings demonstrate PCMA's usefulness in crafting local, culturally sensitive, tailored interventions for stigma reduction. The study emphasizes the necessity of holistic approaches that address individual experiences and societal perceptions, offering a model to conduct similar exercises in diverse local settings.

Exploring the Activation of Target Words in Picture Naming in Children Who Stutter: Evidence From Event-Related Potentials.

PURPOSE: Target word activation in picture naming was explored in children who stutter (CWS) and typically fluent children (TFC) using event-related potentials (ERPs). METHOD: A total of 18 CWS and 16 TFC completed a task combining picture naming and probe word identification. On each trial, a picture-to-be-named was followed by an auditory probe word-to-be-identified; the probe was identical (Identity condition) or Unrelated to the picture name. ERPs were recorded from probe onset. Attenuation of the N400 ERP component was predicted to Identity versus Unrelated trials (N400 priming). Between-groups differences in amplitude, timing, and topography of N400 priming were explored. RESULTS: Naming was more accurate on Identity versus Unrelated trials. Probe word identification accuracy was not affected by Condition. N400 priming was detected, indicating that self-generated picture names facilitated semantic processing of identical probes. This effect was larger in amplitude in CWS versus TFC. Unexpectedly, an N400-preceding, frontally maximal, positive-going ERP component-associated with expectancy processing-was larger in amplitude to Unrelated versus Identity trials. This effect was smaller in CWS versus TFC. CONCLUSIONS: A larger N400 priming effect in CWS versus TFC reflects a tendency toward more extensive semantic processing in picture naming in CWS. A smaller Condition effect on frontally maximal, positive-going, N400-preceding ERP activity in CWS versus TFC indicates a reduced ability to form expectancies about the lexical and/or phonological identity of probe words in CWS. Both effects may point to inefficient activation of target words in picture naming in CWS.

Treatment for preschool age children who stutter: Protocol of a randomised, non-inferiority parallel group pragmatic trial with Mini-KIDS, social cognitive behaviour treatment and the Lidcombe Program-TreatPaCS.

Stuttering is a speech disorder in which the flow of speech is disrupted by involuntary repetitions of sounds, syllables, words or phrases, stretched sounds or silent pauses in which the person is unable to produce sounds and sound transitions. Treatment success is the highest if stuttering is treated before the age of 6 years, before it develops into "persistent" stuttering. Stuttering treatment programs that focus directly on the speech of the child, like the Lidcombe Program, have shown to be effective in this age group. Mini-KIDS is also a treatment that focuses directly on the speech of the child. It is possible that capturing the increased brain plasticity at this age in combination with creating optimal conditions for recovery underlie these treatments' success rate. A treatment focusing on the cognitions, emotions and behaviour of the child, the social cognitive behaviour treatment (SCBT), is also frequently delivered in Belgium. In this study we want to compare, and collect data on the effectiveness, of these three treatment programs: Mini-KIDS, SCBT and the Lidcombe Program (protocol registered under number NCT05185726). 249 children will be allocated to one of three treatment groups. Stuttering specialists will treat the child (and guide the parents) with Mini-KIDS, the SCBT or the Lidcombe Program. They will be trained to deliver the programs meticulously. At 18 months after randomisation, the speech fluency of the child and the attitude of the child and parent(s) towards speech will be measured. It is expected that the three programs will achieve the same (near) zero levels of stuttering in nearly all children and a positive attitude towards speech at 18 months after the start of treatment. The amount of treatment hours to reach the (near) zero levels of stuttering will be compared between the different programmes. For families as well as for the health system this could generate important information.

Auditory Processing of Speech and Nonspeech in People Who Stutter.

PURPOSE: We investigated speech and nonspeech auditory processing of temporal and spectral cues in people who do and do not stutter. We also asked whether self-reported stuttering severity was predicted by performance on the auditory processing measures. METHOD: People who stutter (n = 23) and people who do not stutter (n = 28) completed a series of four auditory processing tasks online. These tasks consisted of speech and nonspeech stimuli differing in spectral or temporal cues. We then used independent-samples t-tests to assess differences in phonetic categorization slopes between groups and linear mixed-effects models to test differences in nonspeech auditory processing between stuttering and nonstuttering groups, and stuttering severity as a function of performance on all auditory processing tasks. RESULTS: We found statistically significant differences between people who do and do not stutter in phonetic categorization of a continuum differing in a temporal cue and in discrimination of nonspeech stimuli differing in a spectral cue. A significant proportion of variance in self-reported stuttering severity was predicted by performance on the auditory processing measures. CONCLUSIONS: Taken together, these results suggest that people who stutter process both speech and nonspeech auditory information differently than people who do not stutter and may point to subtle differences in auditory processing that could contribute to stuttering. We also note that these patterns could be the consequence of listening to one's own speech, rather than the cause of production differences.

Electroencephalographic Classification Reveals Atypical Speech Motor Planning in Stuttering Adults.

PURPOSE: This study explores speech motor planning in adults who stutter (AWS) and adults who do not stutter (ANS) by applying machine learning algorithms to electroencephalographic (EEG) signals. In this study, we developed a technique to holistically examine neural activity differences in speaking and silent reading conditions across the entire cortical surface. This approach allows us to test the hypothesis that AWS will exhibit lower separability of the speech motor planning condition. METHOD: We used the silent reading condition as a control condition to isolate speech motor planning activity. We classified EEG signals from AWS and ANS individuals into speaking and silent reading categories using kernel support vector machines. We used relative complexities of the learned classifiers to compare speech motor planning discernibility for both classes. RESULTS: AWS group classifiers require a more complex decision boundary to separate speech motor planning and silent reading classes. CONCLUSIONS: These findings indicate that the EEG signals associated with speech motor planning are less discernible in AWS, which may result from altered neuronal dynamics in AWS. Our results support the hypothesis that AWS exhibit lower inherent separability of the silent reading and speech motor planning conditions. Further investigation may identify and compare the features leveraged for speech motor classification in AWS and ANS. These observations may have clinical value for developing novel speech therapies or assistive devices for AWS.

Stutterers' experiences on classic psychedelics: A preliminary self-report study.

Stuttering poses challenges to social, occupational, and educational aspects of life. Traditional behavioral therapies can be helpful but effects are often limited. Pharmaceutical treatments have been explored but there are no FDA-approved treatments for stuttering. Interest has grown in the potential use of classic psychedelics, including psilocybin and LSD, which have shown effectiveness in treating disorders with similar symptoms (e.g., anxiety, depression, PTSD). The potential effects of psychedelics on stuttering have not been explored. We conducted a preliminary investigation of self-identified stutterers who report their experiences taking classic psychedelics on the online messaging forum, Reddit. We qualitatively analyzed 114 publicly available posts, extracting meaningful units and assigning descriptor codes inductively. We then deductively organized responses into an established framework of psychedelics which includes behavioral, emotional, cognitive, belief-based, and social effects. These effects were subsequently grouped under organizing themes (positive, negative, neutral). Descriptive statistics revealed that the majority of users (74.0%) reported positive overall short-term effects particularly related to behavioral and emotional change (e.g., reduced stuttering and anxiety), but negative (9.6%), mixed (positive and negative; 4.8%), and neutral overall experiences (11.6%) were also reported. The results support the possibility that psychedelics may impact stuttering, but caution must be applied in their interpretation given the entirely uncontrolled research setting and potential adverse health effects of psychedelics as reported elsewhere. While these results do not encourage the use of psychedelics by stutterers, they suggest that future work could examine the impact of psychedelics on stuttering under supervised and in clinically controlled settings.

Allergies, asthma, and sleep problems in adults who stutter.

PURPOSE: Previous studies have suggested that allergies, asthma, and sleep problems are prevalent in those who stutter. This study analyzed similar data for a broad age group of adults who stutter (AWS). METHOD: Data from the 2012 National Health Interview Survey were analyzed. Adults from 18 to 60 + years of age reported a) to have stuttered, b) to have had any allergy, asthma, or acid reflux, c) to have had insomnia/trouble sleeping and daytime negative consequences, and d) average sleeping hours per day in the past 12 months. RESULTS: The sample included 320 AWS and 33,043 controls. AWS were at greater odds of respiratory, food, and skin allergies (OR = 2.38, 2.36, and 2.09, respectively), as well as asthma and acid reflux (OR = 2.30 and 2.01, respectively) than controls. AWS were at greater odds of insomnia/trouble sleeping, oversleeping, excessive sleepiness, and fatigue than controls (OR = 2.11, 1.71, 2.67, and 1.81, respectively). The subgroup of AWS with no allergy, asthma, and acid reflux were also at greater odds of insomnia/trouble sleeping and excessive sleepiness than controls (OR = 2.13 and 3.11, respectively). Differences were found in specific age groups: younger/middle-aged AWS reported more allergies, asthma, and acid reflux than controls, while older AWS did not; younger/middle-aged AWS reported more insomnia/trouble sleeping than controls, while older AWS reported more oversleeping. CONCLUSIONS: Findings on younger and middle-aged AWS are similar to previous ones on children and adolescents who stutter. Differences regarding younger/middle-aged and older AWS could be consequence of environmental variables.

Stuttering in adolescence and the risk for dysglycemia in early adulthood.

AIMS: To investigate the association between stuttering during adolescence and the onset of dysglycemia (prediabetes or type 2 diabetes) in early adulthood among men and women. MATERIALS AND METHODS: This cohort study included Maccabi Health Services members assessed for mandatory military service at ages 16-19 during 1990-2019 and followed until 31 December 2020. Stuttering status was recorded in the baseline medical evaluation. Incident cases of dysglycemia were identified systematically using prediabetes and diabetes registries. Cox proportional hazard models were applied for men and women separately, adjusting for sociodemographics and medical status. RESULTS: The study cohort comprised 866,304 individuals (55% men; 0.21% with stuttering) followed for a total of 12,696,250 person-years. During the study period, 7.6% (n = 36,603) of men and 9.0% (n = 34,723) of women were diagnosed with dysglycemia. The mean ages at diagnosis were 34 and 32 years for men and women, respectively. Women with stuttering exhibited the highest dysglycemia incidence rate (102.3 per 10,000 person-years) compared with the other groups (61.4, 69.0, and 51.9 per 10,000 person-years for women without stuttering, men with stuttering, and men without stuttering, respectively). For both men and women, those with stuttering showed an increased risk of being diagnosed with dysglycemia compared with those without (adjusted hazard ratios 1.18 [1.01-1.38] and 1.61 [1.15-2.26], respectively). The associations persisted in extensive sub-analyses. CONCLUSIONS: Stuttering in adolescence is associated with a higher risk of dysglycemia in early adulthood for men and women. Screening and targeted prevention in this population, especially women, may be beneficial.

Caregiver Predictions of Their 3- to 6-Year-Old Child Who Stutters' Communication Attitude.

PURPOSE: Caregivers share critical insight during their child's stuttering evaluation; yet, there have been no empirical studies evaluating whether caregivers provide similar accounts of their 3- to 6-year-old child's communication attitude compared to their child's self-report. This study examined caregiver- and child-reported communication attitude and assessed potential moderators of more comparable caregiver and child ratings (i.e., caregiver confidence, caregiver-child conflict, observer-rated stuttering severity). METHOD: One hundred thirteen children who stutter ages 3 through 6 years and a primary caregiver were recruited from clinical settings across the United States. Children completed the Communication Attitude Test for Preschool and Kindergarten Children Who Stutter (KiddyCAT) and three speaking samples, which were recorded to assess observer-rated stuttering severity using the Stuttering Severity Instrument-Fourth Edition. Caregivers predicted their child's communication attitude (C-KiddyCAT) and provided a confidence rating for their prediction. Caregivers also rated caregiver-child conflict using the Child-Parent Relationship Scale-Short Form (CPRS-SF). Multiple regression was used to (a) evaluate whether caregiver C-KiddyCAT scores predicted child KiddyCAT scores and (b) assess potential moderators of the relationship between C-KiddyCAT and KiddyCAT scores. RESULTS: Caregiver ratings of their child's communication attitude (C-KiddyCAT) predicted child communication attitude ratings (KiddyCAT). A significant interaction between caregiver-child conflict (CPRS-SF) and caregiver ratings of their child's communication attitude (C-KiddyCAT) suggested caregiver-child conflict changed the underlying relationship between C-KiddyCAT and KiddyCAT scores, such that low conflict resulted in more similar C-KiddyCAT and KiddyCAT scores. Neither caregiver confidence nor observer-rated stuttering severity influenced the relationship between C-KiddyCAT and KiddyCAT scores. CONCLUSIONS: Although many caregivers predicted communication attitude ratings that closely aligned with their child's report, some caregiver-child dyads provided divergent ratings. Clinicians should interpret caregiver predictions of their child's communication attitude within the context of their full evaluation and the caregiver-child relationship. Assessing both self-reported communication attitude and caregiver predictions of their child's communication attitude provides a meaningful starting point to counseling caregivers about cognitive components of stuttering for preschool- and kindergarten-age children who stutter.

Self-Perceived Communication Competence of Adults Who Stutter Following Communication-Centered Treatment.

PURPOSE: The purpose of this study was to assess self-perceived communication competence of adults who stutter following participation in a non-ableist treatment for which one of the core components focuses on communication - with no direct or indirect goals designed to reduce or modify stuttered speech. METHOD: Thirty-three adults who stutter completed the Self-Perceived Communication Competence scale (McCroskey & McCroskey, 1988) pre- and posttreatment. RESULTS: Findings indicate significant gains in self-perceived communication competence posttreatment. Pre- to posttreatment changes in stuttering did not predict posttreatment gains in self-perceived communication competence. CONCLUSION: The present study demonstrates that improvement in communication can be achieved independent of improvement in fluency, lending further support to the notion that stuttering and communication competence are distinct constructs.

Lower nonword syllable sequence repetition accuracy in adults who stutter is related to differences in audio-motor oscillations.

OBJECTIVE: The goal of this study was to use independent component analysis (ICA) of high-density electroencephalography (EEG) to investigate whether differences in audio-motor neural oscillations are related to nonword syllable repetition accuracy in a group of adults who stutter compared to typically fluent speakers. METHODS: EEG was recorded using 128 channels from 23 typically fluent speakers and 23 adults who stutter matched for age, sex, and handedness. EEG was recorded during delayed, 2 and 4 bilabial nonword syllable repetition conditions. Scalp-topography, dipole source estimates, and power spectral density (PSD) were computed for each independent component (IC) and used to cluster similar ICs across participants. Event-related spectral perturbations (ERSPs) were computed for each IC cluster to examine changes over time in the repetition conditions and to examine how dynamic changes in ERSPs are related to syllable repetition accuracy. RESULTS: Findings indicated significantly lower accuracy on a measure of percentage correct trials in the AWS group and for a normalized measure of syllable load performance across conditions. Analysis of ERSPs revealed significantly lower alpha/beta ERD in left and right µ ICs and in left and right posterior temporal lobe α ICs in AWS compared to TFS (CC p < 0.05). Pearson correlations with %CT for frequency across time showed strong relationships with accuracy (FWE<0.05) during maintenance in the TFS group and during execution in the AWS group. CONCLUSIONS: Findings implicate lower alpha/beta ERD (8-30 Hz) during syllable encoding over posterior temporal ICs and execution in left temporal/sensorimotor components. Strong correlations with accuracy and interindividual differences in ∼6-8 Hz ERSPs during execution implicate differences in motor and auditory-sensory monitoring during syllable sequence execution in AWS.

Evidence for planning and motor subtypes of stuttering based on resting state functional connectivity.

We tested the hypothesis, generated from the Gradient Order Directions Into Velocities of Articulators (GODIVA) model, that adults who stutter (AWS) may comprise subtypes based on differing connectivity within the cortico-basal ganglia planning or motor loop. Resting state functional connectivity from 91 AWS and 79 controls was measured for all GODIVA model connections. Based on a principal components analysis, two connections accounted for most of the connectivity variability in AWS: left thalamus - left posterior inferior frontal sulcus (planning loop component) and left supplementary motor area - left ventral premotor cortex (motor loop component). A k-means clustering algorithm using the two connections revealed three clusters of AWS. Cluster 1 was significantly different from controls in both connections; Cluster 2 was significantly different in only the planning loop; and Cluster 3 was significantly different in only the motor loop. These findings suggest the presence of planning and motor subtypes of stuttering.

Observer-rated outcomes of communication-centered treatment for adults who stutter: A social validation study.

Previous studies have reported that adults who stutter demonstrate significant gains in communication competence, per self-ratings and clinician-ratings, upon completion of a communication-centered treatment, or CCT. The purpose of this social validation study was to determine whether communication competence ratings reported by untrained observers are consistent with client and clinician judgments of communication competence gains following CCT. Eighty-one untrained observers completed an online survey that required each to view one of two videos depicting an adult who stutters during a mock interview recorded prior to CCT or after CCT. Observers were then asked to rate the communication competence of the interviewee on a 100-point visual analog scale and provide additional demographic information. Communication competence of the adult who stutters who had completed CCT was rated significantly higher in their post-treatment video. Upon controlling for two demographic factors found to be associated with observer ratings (years of education, years the observers had known an adult who stutters), significantly higher ratings of communication competence for the post-treatment video were maintained. These preliminary findings provide social validity for CCT by demonstrating that the gains in communication competence reported in previous studies through clinician and client observations are also reported by untrained observers who are not familiar with CCT.