Evaluating three stuttering assessments through network analysis, random forests and cluster analysis

Higher Frequency of Stuttered Disfluencies Negatively Affects Communicative Participation in Parkinson's Disease

PURPOSE

Up to 90% of people with Parkinson's disease (PD) develop communication difficulties over the course of the disease. While the negative effect of dysarthria on communicative participation has been well-documented, the impact of the occurrence of acquired stuttered disfluencies on communication in different speech situations is unknown. This study aimed to determine if the frequency of occurrence of stuttered disfluencies affects communicative participation in individuals with PD, and whether such a relationship is mediated by examiner- and self-rated measures of disease severity.

METHOD

Conversational speech samples were collected from 100 people with PD aged 53-91 years to calculate the frequency of occurrence of stuttered disfluencies. Participants completed the Communicative Participation Item Bank to assess participation in communicative situations. Information on overall speech, cognitive, and motor performance was collected using both self-rated and examiner-rated methods.

RESULTS

Participants with PD presented with 0.2%-9.9% stuttered disfluencies during conversation. Overall, participants with PD reported their communicative participation to be impacted "a little" (19.5 ± 7.0), but there was considerable interindividual variation. A higher frequency of stuttered disfluencies was associated with significantly lower communicative participation (ρ = -0.32, p < .01). In addition, examiner-rated frequency of stuttered disfluencies (p < .01), speech (p < .01), and motor severity (p = .04) were all significant predictors of communicative participation. Using self-ratings, speech (p < .01) and cognitive (p < .01) measures significantly predicted communicative participation.

CONCLUSIONS

In people with PD, communicative participation was significantly worse for those with a higher frequency of stuttered disfluencies. Examiner- and self-rated measures of disease severity contributed different information related to communicative constraints. Together, these results highlight the importance of individualized and holistic speech therapy that considers a wide variety of symptoms, including stuttered disfluencies, to ensure positive functional outcomes.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26850169.

EXPLANA: A user-friendly workflow for EXPLoratory ANAlysis and feature selection in cross-sectional and longitudinal microbiome studies

Motivation

Longitudinal microbiome studies (LMS) are increasingly common but have analytic challenges including non-independent data requiring mixed-effects models and large amounts of data that motivate exploratory analysis to identify factors related to outcome variables. Although change analysis (i.e. calculating deltas between values at different timepoints) can be powerful, how to best conduct these analyses is not always clear. For example, observational LMS measurements show natural fluctuations, so baseline might not be a reference of primary interest; whereas, for interventional LMS, baseline is a key reference point, often indicating the start of treatment.

Results

To address these challenges, we developed a feature selection workflow for cross-sectional and LMS that supports numerical and categorical data called EXPLANA (EXPLoratory ANAlysis). Machine-learning methods were combined with different types of change calculations and downstream interpretation methods to identify statistically meaningful variables and explain their relationship to outcomes. EXPLANA generates an interactive report that textually and graphically summarizes methods and results. EXPLANA had good performance on simulated data, with an average area under the curve (AUC) of 0.91 (range: 0.79-1.0, SD = 0.05), outperformed an existing tool (AUC: 0.95 vs. 0.56), and identified novel order-dependent categorical feature changes. EXPLANA is broadly applicable and simplifies analytics for identifying features related to outcomes of interest.

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.

Localization of stuttering based on causal brain lesions

Stuttering affects approximately 1 in 100 adults and can result in significant communication problems and social anxiety. It most often occurs as a developmental disorder but can also be caused by focal brain damage. These latter cases may lend unique insight into the brain regions causing stuttering. Here, we investigated the neuroanatomical substrate of stuttering using three independent datasets: (i) case reports from the published literature of acquired neurogenic stuttering following stroke (n = 20, 14 males/six females, 16-77 years); (ii) a clinical single study cohort with acquired neurogenic stuttering following stroke (n = 20, 13 males/seven females, 45-87 years); and (iii) adults with persistent developmental stuttering (n = 20, 14 males/six females, 18-43 years). We used the first two datasets and lesion network mapping to test whether lesions causing acquired stuttering map to a common brain network. We then used the third dataset to test whether this lesion-based network was relevant to developmental stuttering. In our literature dataset, we found that lesions causing stuttering occurred in multiple heterogeneous brain regions, but these lesion locations were all functionally connected to a common network centred around the left putamen, including the claustrum, amygdalostriatal transition area and other adjacent areas. This finding was shown to be specific for stuttering (PFWE < 0.05) and reproducible in our independent clinical cohort of patients with stroke-induced stuttering (PFWE < 0.05), resulting in a common acquired stuttering network across both stroke datasets. Within the common acquired stuttering network, we found a significant association between grey matter volume and stuttering impact for adults with persistent developmental stuttering in the left posteroventral putamen, extending into the adjacent claustrum and amygdalostriatal transition area (PFWE < 0.05). We conclude that lesions causing acquired neurogenic stuttering map to a common brain network, centred to the left putamen, claustrum and amygdalostriatal transition area. The association of this lesion-based network with symptom severity in developmental stuttering suggests a shared neuroanatomy across aetiologies.

Self-Reported Stuttering Severity Is Accurate: Informing Methods for Large-Scale Data Collection in Stuttering

PURPOSE

To our knowledge, there are no data examining the agreement between self-reported and clinician-rated stuttering severity. In the era of big data, self-reported ratings have great potential utility for large-scale data collection, where cost and time preclude in-depth assessment by a clinician. Equally, there is increasing emphasis on the need to recognize an individual's experience of their own condition. Here, we examined the agreement between self-reported stuttering severity compared to clinician ratings during a speech assessment. As a secondary objective, we determined whether self-reported stuttering severity correlated with an individual's subjective impact of stuttering.

METHOD

Speech-language pathologists conducted face-to-face speech assessments with 195 participants (137 males) aged 5-84 years, recruited from a cohort of people with self-reported stuttering. Stuttering severity was rated on a 10-point scale by the participant and by two speech-language pathologists. Participants also completed the Overall Assessment of the Subjective Experience of Stuttering (OASES). Clinician and participant ratings were compared. The association between stuttering severity and the OASES scores was examined.

RESULTS

There was a strong positive correlation between speech-language pathologist and participant-reported ratings of stuttering severity. Participant-reported stuttering severity correlated weakly with the four OASES domains and with the OASES overall impact score.

CONCLUSIONS

Participants were able to accurately rate their stuttering severity during a speech assessment using a simple one-item question. This finding indicates that self-report stuttering severity is a suitable method for large-scale data collection. Findings also support the collection of self-report subjective experience data using questionnaires, such as the OASES, which add vital information about the participants' experience of stuttering that is not captured by overt speech severity ratings alone.

"I Just Want People to Think I'm Normal": An Interview Study of Young Swedish Women With Covert Stuttering

PURPOSE

Research indicates that there is a tendency for females who stutter, more often than males, to use coping strategies that involve covering their stutter, for example, by avoiding situations that require verbal participation. The aim of the study is to increase knowledge about how covert stuttering develops and its impact on self-image and quality of life for women who stutter.

METHOD

Eleven young women who stutter covertly were interviewed, and data were subjected to qualitative content analysis. Background information was obtained from the self-report instruments measuring the impact of stuttering on different aspects of life (Overall Assessment of the Speaker's Experiences of Stuttering) and degree of perceived social anxiety (Liebowitz Social Anxiety Scale, Self-Report).

RESULTS

Three main themes were identified: (a) managing stuttering, (b) personal aspects, and (c) stuttering as a phenomenon. Shame and a desire to fit in emerged as distinct motives for covering stuttering. The women described that stuttering controlled both life choices and everyday life. Development of self-image had been strongly negatively affected, resulting in social anxiety. The women expressed a particular vulnerability of being a woman who stutters, due to societal norms of female behavior and a lack of female role models who stutter.

CONCLUSIONS

The choice of coping strategy was motivated by a desire to "be normal." As a result, stuttering had come to dominate life and affect self-image and life choices. The study highlights the importance for clinicians to be alert to and aware of the fact that the experiences of women who stutter can lead them to develop coping strategies that have far-reaching negative consequences.

Covert and overt stuttering: Concepts and comparative findings

PURPOSE

One way of conceptualizing stuttering is on a continuum from primarily covert to primarily overt. Assertions have been made as to how those with covert stuttering might be impacted differently to those with overt stuttering, but findings from well-controlled studies remain scarce. The principal aim of the present study was to compare the impact of stuttering and emotional distress related to two subgroups of persons who stutter: people with primarily overt stuttering and people with primarily covert stuttering. In exploring this, we also offer some preliminary thoughts on challenges with the terminology surrounding the concepts of 'overtness' and 'covertness'.

METHODS

Twenty-one adults already enrolled in a multiple, single-case treatment study (Sønsterud et al., 2019, 2020) took part in the present study, and underwent a battery of tests that assessed anxiety, depression, fear of negative evaluation, and quality of life. The sub-groups were identified on the basis of self-categorization using the Tomaiuoli, Del Gado, Spinetti, Capparelli, and Venuti (2015) classification, as well as the evaluation of speech samples from two independent SLPs (Sønsterud et al., 2020). The classifications were further explored by five independent 'lay' assessors who reviewed pre-therapy video and rated participants' speech on a 4-point Likert Stuttering Probability Scale (1 = 'fluent with no doubt', 2 = 'fluent with some doubt', 3 = 'stuttering with some doubt' and 4 = 'stuttering with no doubt').

RESULTS

No significant differences were found between the primarily overt and primarily covert groups in relation to self-reported symptoms of anxiety, depression, and fear of negative evaluation. However, investigation at item level identified a significant difference in linguistic avoidance between the two groups.

CONCLUSION

There may be fewer differences between people with primarily overt and primarily covert stuttering than previously thought with regards to emotional impact, as well as most aspects of avoidance behavior.

The Complexity of Stuttering Behavior in Adults and Adolescents: Relationship to Age, Severity, Mental Health, Impact of Stuttering, and Behavioral Treatment Outcome

PURPOSE

This study investigated the complexity of stuttering behavior. It described and classified the complexity of stuttering behavior in relation to age, behavioral treatment outcomes, stuttering severity, anxiety-related mental health, impact of stuttering, and gender.

METHOD

For this study, a taxonomy was developed-LBDL-C7-which was based on the Lidcombe Behavioral Data Language of stuttering. It was used by five experienced judges to analyze the complexity of stuttering behavior for 84 adults and adolescents before and after speech restructuring treatment. Data were 3,100 stuttering moments, which were analyzed with nominal logistic regression.

RESULTS

The complexity of stuttering behavior appears not to change as a result of treatment, but it does appear to change with advancing age. Complexity of stuttering behavior was found to be independently associated with clinician stuttering severity scores but not with percentage of syllables stuttered or self-reported stuttering severity. Complexity of stuttering behavior was not associated with gender, anxiety, or impact of stuttering.

CONCLUSION

Clinical and research applications of these findings are discussed.