This study uses ultrasound to image onset velar stop consonant articulation in words. By examining tongue body placement, the extent of velar closure variation across vowel contexts provides for the measurement of anticipatory coarticulation while productions within the same vowel context provide measurement of extent of token-to-token variation. Articulate Assistant Advanced 2.0 software was used to semi-automatically generate midsagittal tongue contours at the initial point of maximum velar closure and was used to fit each contour to a curved spline. Patterns of lingual coarticulation and measures of speech motor stability, based on curve-to-curve distance (Zharkova, Hewlett, & Hardcastle, 2011), are investigated to compare the speech of typically fluent speakers to the speech of people who stutter. Anticipatory coarticulation can be interpreted as a quantitative measure indicating the maturity of the speech motor system and its planning abilities. Token-to-token variability is examined from multiple velar vowel productions within the same vowel context, describing the accuracy of control, or stability, of velar closure gestures. Measures for both speaking groups are examined across the lifespan at stages during speech development, maturation, and aging. Results indicate an overall age effect, interpreted as refinement, with increased speech stability and progressively more segmental (less coarticulated) productions across the lifespan. A tendency toward decreased stability and more coarticulated speech was found for younger people who stutter, but this difference was small and absent among older adults. Outcomes of this study suggest the articulatory maturation trajectories of people who stutter may be delayed, but overall maturation of the speech mechanism is evident by older adulthood for typically fluent speakers and those who stutter. Applications to intervention are discussed in closing.

Objective: A neuroscientific picture-word task was used to investigate semantic and phonological activation spreading in adults who stutter (AWS). Method: Fourteen AWS and 14 adults who do not stutter (AWNS) participated. On each trial, a picture was named at a delay. Sometimes, an attended probe word was heard before naming. Some probes were Semantically-Related to the labels. Those same probes also appeared following pictures with Unrelated labels. N400 ERPs recorded to these two probe types were compared (Semantically-Related versus Unrelated). Other probes were Phonologically-Related to the labels. Those same probes also appeared following pictures with unrelated labels (P-Unrelated). N400 ERPs recorded to these two probe types were compared (Phonologically-Related versus P-Unrelated). Results: AWNS exhibited typical N400 priming effects. AWS exhibited non-robust Semantic N400 priming, and a reverse Phonological N400 priming effect. Conclusions: Results suggest that AWS use attentional control strategies to influence the activation of words in the mental lexicon.

The purpose of the present study was to explore whether the phonological encoding difficulties that have been demonstrated in children who stutter persist in adults whose stuttering persists. This hypothesis was investigated by comparing the phonological working memory of adults who stutter (AWS) and adults who do not stutter (AWNS) using non-word repetition and phoneme elision tasks. Twenty-four adults (age range = 17;9 to 46;11 mean age = 28;2): 12 AWS and 12 AWNS matched on gender and age participated in this study. A total of 48 non-words consisting of an equal number (N = 12 per syllable length category) of two-syllable, three-syllable, four-syllable and seven-syllable non-words were selected for use in the non-word repetition and phoneme elision tasks. In the non-word repetition task, results showed a significant interaction between fluency group and syllable length for the 7-syllable length category only, indicating that AWS require a significantly higher mean number of attempts than AWNS. Results of the phoneme elision task revealed a significant main effect for syllable length with both groups demonstrating a significant reduction in accuracy as the non-words increased in length, but there was no significant interaction between fluency group and syllable class length. Potential implications of these findings are presented along with recommendations for future research. / text

There are data to suggest that the phonological representations of young children who stutter are less specified than their typically fluent peers. The purpose of the present study is to determine if this apparent difference in phonological encoding persists in adults who stutter. Utilizing a false memory paradigm, nine adults who stutter (AWS) were asked to listen to and then recall/produce 12 lists of 12 words each. Each word list was comprised of either semantic, phonological or an equal number of semantic and phonological associates of a single, unpresented, critical ‘lure’ word. Three parameters of recall performance were measured across these three conditions: 1) number of accurately recalled productions, 2) number of lure intrusions and 3) number of other intrusions. AWS produced significantly more accurate recalls in the semantic condition than either the hybrid or phonological conditions, and significantly more lure intrusions in the phonological and hybrid conditions than the semantic condition, but there was no significant difference on measures of other intrusions. These results extend the findings with young children who stutter, and indicate that the phonological representations are less robust than the semantic representations in the lexicon of AWS. / text

I denna studie undersöktes effekten av förstärkt hörselåterkoppling (enhanced auditoryfeedback, EAF) på observerbar stamning och upplevd känsla av talflyt hos vuxna personer som stammar. Så vitt vi vet finns inga tidigare studier av effekten av förstärkt hörselåterkoppling vid stamning. Mycket forskning finns dock på andra typer av hörselåterkoppling, som exempelvis frekvensförändrad hörselåterkoppling (frequencyaltered feedback, FAF), där man sett positiv effekt på talflytet hos personer som stammar. Deltagargruppen bestod av 14 personer i åldrarna 20-43 år, som stammade. Deltagarna fick läsa högt under olika förhållanden av hörselåterkoppling, de olika förhållandena som testades var förstärkt hörselåterkoppling och FAF mot normal hörselåterkoppling. Testtillfällena spelades in och procent stammade stavelser (%SS) räknades för en objektiv bedömning av talflytet. Deltagarna fick också skatta hur de upplevde talflytet under de olika förhållandena. Såväl observerbar stamning som skattning av upplevt talflyt visade en positiv tendens vid både förstärkt hörselåterkoppling och FAF. Förändringen var statistiskt signifikant för observerbar stamning vid FAF (p = 0,002), och för skattningen av upplevt talflyt vid både förstärkthörselåterkoppling (p = 0,0053) och FAF (p = 0,021). Att förändringen i observerbarstamning vid förstärkt hörselåterkoppling inte var statistiskt signifikant (p = 0,117) kanbero på relativt låg power hos studien, särskilt som två deltagare inte uppvisade någon stamning alls i testsituationen. De positiva resultaten gällande skattningen samt de positiva tendenserna i observerbar stamning (%SS) i denna studie motiverar fortsatt forskning om förstärkt hörselåterkoppling vid stamning. / This study examined the effects of enhanced auditory feedback (EAF) on observable stuttering and perceived sense of speech fluency in adults who stutter. To our knowledge there are no previous studies on the effects of EAF on stuttering. There are numerous studies on other types of altered auditory feedback, such as frequency altered feedback (FAF), in which a positive effect on speech fluency in people who stutter has been shown. The group of participants consisted of 14 people aged from 20-43 years, who stuttered. Participants were asked to read aloud during different conditions of auditory feedback, the different conditions tested were EAF and FAF compared to normal auditory feedback. The testing was recorded and the percentage of syllables stuttered (% SS) was calculated for an objective assessment of speech fluency. Participants were also asked to estimate how they perceived their speech fluency during the various conditions. Both observable stuttering and the ratings of experienced speech fluency showed a positive trend in both EAF and FAF. The change was statistically significant for observable stuttering in FAF (p = 0.002), and for the estimation of experienced speech fluency in both EAF (p = 0.0053) and FAF (p = 0.021). The lack of statistical significance for the change in observable stuttering during EAF (p = 0.117) may be due to relatively low power of the study, particularly as two participants showed no stuttering at all during the test conditions. The positive results regarding the estimation and the positive trends of observable stuttering (% SS) in this study motivates for further research on the effects of enhanced auditory feedback on stuttering.

Tyrime dalyvavo 74 Lietuvoje gyvenantys mikčiojantys asmenys nuo 17 iki 58 metų amžiaus (iš jų 38 vyrai ir 36 moterys) ir 74 nemikčiojantys asmenys nuo 18 iki 51 metų (37 vyrai ir 37 moterys). Tiriamiesiems pateikta interneto svetainėje patalpinta apklausa, susidedanti iš diferencinio vienišumo klausimyno, socialinio aprūpinimo klausimyno ir nerimo socialinėse interakcijose klausimyno. Taip pat pateikta socialinių-demografinių klausimų. Gauti rezultatai rodo, jog vieniši mikčiojantys asmenys jaučia daugiau socialinio nerimo ir gauna mažiau socialinio palaikymo, lyginant su nevienišais mikčiojančiais asmenimis. Be to, vieniši mikčiojantys asmenys, gaunantys daugiau socialinio palaikymo, jaučia mažiau socialinio nerimo negu vieniši mikčiojantys asmenys, gaunantys mažiau socialinio palaikymo. Taip pat apskaičiuota, jog apskritai mikčiojančiojo amžius neturi sąsajos su jo gaunamu socialiniu palaikymu, tačiau kuo vyresnis yra mikčiojantis asmuo, tuo mažiau jis jausis socialiai integruotas, ir atvirkščiai. Tyrimo rezultatai rodo, jog mikčiojančiųjų vienišumą paaiškina mažas socialinis palaikymas ir didelis socialinis nerimas, o socialinį nerimą paaiškina stipresnis mikčiojimas. / 74 stuterrers currently residing in Lithuania, aged 17-58, (38 men and 36 women) and 74 non-stutterers, also currently residing in Lithuania, aged 18-51 (37 men and 37 women), took part in the research. The respondents filled out an online survey consisting of the Differential Loneliness Scale, the Social Provisions Scale and the Social Interaction Anxiety Scale. Some sociodemographic questions were also included in the survey. The results show that lonely stuttering adults had higher levels of social anxiety and received less social support than their less lonely counterparts. Also, lonely stuttering adults who received more social support had lower levels of social anxiety than lonely stuttering adults who received less social support. It was also calculated that the stutterer‘s age does not have any direct linkage to their level of received social support, however, the older a stutterer gets, the less socially integrated he or she will feel. The results also show that the stutterers‘ loneliness was buffered by higher levels of social support and negatively affected by higher levels of social anxiety. Moreover, social anxiety was shown to be negatively affected by more severe stuttering.

Stuttering has been a complex problem ever since the early history of man. It has been found to exist in some cultures to a greater extent than in others. In certain primitive cultures the phenomenon of stuttering was reported to be unknown, yet when members of these cultures were influenced by western environments some incidence of stuttering occurred among them. The influence of the environment therefore cannot be disregarded when considering causes of stuttering. Although much research has been done by speech pathologists among various world cultures they have by no means completed their task for there are many groups, living in a variety of societies, which are yet to be studied. The present rudimentary investigation into stuttering among Indians living in Durban may be regarded as a contribution to the knowledge that has already been accumulated. / Thesis (M.A.)-University of Natal, Durban, 1971.

Current research in stuttering suggests that individuals who stutter (IWS) may have a hyperactive error-monitoring system, leading to the exacerbation and anticipation of verbal dysfluencies. Using a neurophysiological marker of error processing known as the feedback error-related negativity, the current thesis involved three studies. First, a pilot study was conducted to ensure that word feedback cues were usable in the current paradigm. Second, a classic virtual T-maze task was used to assess the generic error processing mechanism of IWS. Third, an adaptation of the T-maze was used to assess the integrity of the reinforcement learning system of IWS and their ability to associate reward and error information of personalized problem words with predictive cues. Results suggest preliminary evidence for functional generic error processing in IWS and disrupted error processing when conditioned predictive cues are needed to predict fluent versus dysfluent outcomes. / Graduate

Submitted by Paula Bianca Meireles Dias de Moura null (paula.diasmoura@gmail.com) on 2016-05-10T19:01:58Z No. of bitstreams: 1 Dissertação_Paula_Moura_versão_FINAL.pdf: 1447189 bytes, checksum: 30dae42a9b78e963e813444ca60d592e (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-13T12:12:59Z (GMT) No. of bitstreams: 1 buzzeti_pbmm_me_mar.pdf: 1447189 bytes, checksum: 30dae42a9b78e963e813444ca60d592e (MD5) / Made available in DSpace on 2016-05-13T12:12:59Z (GMT). No. of bitstreams: 1 buzzeti_pbmm_me_mar.pdf: 1447189 bytes, checksum: 30dae42a9b78e963e813444ca60d592e (MD5) Previous issue date: 2016-04-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Pesquisas científicas têm apontado os benefícios do atraso na retroalimentação auditiva na fluência de pessoas que gaguejam. Entretanto, existe uma grande variabilidade nos resultados e nem todos os indivíduos apresentam uma melhora significativa com a utilização deste recurso. Com base na hipótese de que os diferentes tipos de disfluências possam influenciar na eficácia do atraso na retroalimentação auditiva como intervenção no tratamento da gagueira, este estudo teve por objetivo analisar os efeitos imediatos do atraso na retroalimentação auditiva sob as diferentes tipologias de disfluências típicas da gagueira, em indivíduos acometidos pelo distúrbio. Participaram desta pesquisa trinta indivíduos, de oito a 46 anos e onze meses, com gagueira do desenvolvimento persistente. Os participantes deveriam apresentar no mínimo 3% de disfluências típicas da gagueira e gagueira leve de acordo com o Instrumento de Gravidade da Gagueira. Foram utilizados os seguintes procedimentos: avaliação audiológica, avaliação da fluência (fala espontânea) em duas situações de escuta - com retroalimentação auditiva habitual (RAH) e atrasada (RAA) - e o Instrumento de Gravidade da Gagueira. O software Fono Tools foi utilizado para provocar o efeito da RAA com atraso de 100 ms. A análise estatística dos dados foi realizada por meio da aplicação do Teste dos Postos Sinalizados Wilcoxon, Teste Qui-quadrado para proporções e Teste da Razão e Verossimilhança. Os resultados mostraram que o atraso na retroalimentação auditiva diminuiu a frequência da maioria das disfluências típicas da gagueira, sendo que a redução de repetição de palavras foi estatisticamente significante. O número de indivíduos que diminuiu repetição de palavras e que manteve intrusões foi estatisticamente significante. Na análise comparativa entre disfluências de duração e de repetição, apenas a redução de disfluências de repetição se mostrou estatisticamente significante. A maioria dos indivíduos diminuiu os fluxos de sílabas por minuto (SPM) e palavras por minuto (PPM) e a redução do fluxo de SPM para o grupo foi significante. Concluiu-se, portanto, que o efeito do atraso na retroalimentação auditiva é mais eficiente para reduzir as disfluências de repetição do que as disfluências de duração, e que embora a taxa de articulação tenha diminuído significantemente sob o efeito da RAA, não houve prejuízo no fluxo de informação. / Scientific researches indicate the benefits of the delayed auditory feedback in fluency of people who stutter. However, there is a great variability in the results and a significant improvement is not demonstrated in all the individuals with the use of this resource. Based on the hypothesis that different types of disfluencies can influence the effectiveness of delayed auditory feedback as an intervention in the treatment of stuttering, this study aimed to compare the immediate effects of delayed auditory feedback in different typologies of stuttering-like disfluencies, for people affected by this disorder. Thirty individuals participated of this research, between the age of eight to 46 years and eleven months, with persistent developmental stuttering. Participants should present at least 3% of stuttering-like disfluencies and mild stuttering according to the Stuttering Severity Instrument. The following procedures were used: audiological evaluation, fluency evaluation (spontaneous speech) in two listening situations - with normal auditory feedback (NAF) and delayed auditory feedback (DAF) - and the Stuttering Severity Instrument. The Fono Tools software was used to create the DAF effects with 100 ms delay. The statistical analyzes were performed by applying the Wilcoxon signed-rank test, Chi-squared test and Likelihood ratio test. The results showed that the delayed auditory feedback decreases the frequency of most stuttering-like disfluencies, and the word repetition reduction was statistically significant. The number of individuals that decreased word repetition and kept intrusion was statistically significant. In the comparative analysis between the duration and repetition disfluencies, only repetition disfluencies reduction was statistically significant. Most individuals decreased flow of syllables per minute (SPM) and words per minute (PPM) and the group reduction of SPM flow was significant. Therefore, the conclusion is that the effect of delayed auditory feedback is more efficient to reduce repetition disfluencies than duration disfluencies, and although articulating rate has significantly decreased under the effect of DAF, there was no loss in the information flow.

The aim of this thesis was to investigate the neural underpinnings of persistent developmental stuttering. We explored neural systems important for speech-motor integration and focused on subcortical control systems: the basal ganglia and cerebellum. A secondary aim of this work was to distinguish effects related to general traits of the disorder from those reflecting specific states of stuttered speech. To address these aims we used a variety of neuroimaging methodologies as well as an extensive neuropsychological and empirical test battery. Our examination of neural pathway microstructure using diffusion-tensor imaging replicated previous findings of widespread disorganisation of white matter in people who stutter. This disruption included all major white matter pathways leading in and out of the cerebellum. In our second, third, and fourth studies we examined functional activity at rest and during different types of speech. The brain networks used by people who stutter and controls largely overlapped. The brain regions that distinguished general traits and specific states of stuttering were somewhat task-specific. Subcortical activation in the basal ganglia and cerebellum was related to the frequency of dysfluent speech in the scanner. In our final study we examined performance on a variety of classical tasks of motor learning. We observed evidence of delayed learning in response to changes in environmental feedback in the stuttering group relative to controls. Within people who stutter, subgroups who differ according to heritability of the disorder may also differ in the balance of dopamine in the basal ganglia. Overall, we concluded that cerebellar alterations contribute to the general trait of stuttering, while basal ganglia disruption may reflect specific effects within stuttering. Our work supports a broader role of the subcortical system in speech production, generally.