Stuttering inhibition via altered auditory feedback during scripted telephone conversations

Indicators of speech fluency in stuttering and in phonological disorder

PURPOSE

To identify the indicators of speech fluency that differs subjects with stuttering, with phonological disorder, and with the two disorders in comorbidity.

METHODS

Thirty subjects aged 4-11 years old were divided into 3 groups, each one with 10 subjects: groups with developmental stuttering (SG), phonological disorder (PDG), and with two diagnoses in comorbidity (SPDG) participated in this study. The procedures were speech fluency and phonology evaluation. The data were submitted to statistical analysis.

RESULTS

Subjects from SG and SPDG showed a greater occurrence of stuttering-like disfluencies and total of disfluencies in relation to the subjects with PDG. Regarding to the other disfluencies, the three groups were similar. Subjects with PDG showed fewer monosyllabic word repetitions, part of word repetition and prolongations in relation to subjects from SG and SPDG. Blocks occurred more frequently in the two groups with stuttering (SG and SPDG) than in the group with PDG. Interjection occurred more frequently in subjects from SG than in PDG.

CONCLUSION

The PDG was the most differentiated in quantitative and qualitative terms in the three groups analyzed. The similarities and differences between the groups will assist the differential diagnosis and, consequently, will enable improved therapy. The presence of blocks represents an important marker for the diagnosis of stuttering.

Immediate effect of delayed auditory feedback on stuttering-like disfluencies

ABSTRACT Objective: to describe the immediate effects of delayed auditory feedback on stuttering-like disfluencies in people who stutter. Methods: a cross-sectional and experimental study. The effect of delayed auditory feedback was analyzed in thirty individuals, from eight to 46 years old, diagnosed 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 in two listening situations - with Non-altered and delayed auditory feedback - and the Stuttering Severity Instrument. The Fono Tools software was used to cause the delay effect. Data analysis was performed using pertinent statistical tests. Results: there was no decrease in most stuttering-like disfluencies. There was a statistically significant reduction in word repetition and flow of syllables per minute. Conclusion: the delay in auditory feedback caused, as an immediate effect, the reduction of word repetition and speech rate, in syllables per minute.

Efeito da retroalimentação auditiva atrasada na gagueira com e sem alteração do processamento auditivo central

RESUMO Objetivo Verificar o efeito da retroalimentação auditiva atrasada na fluência da fala de indivíduos que gaguejam, com e sem alteração do processamento auditivo central. Método Participaram 20 indivíduos com gagueira, de sete a 17 anos, divididos em dois grupos, cada um com 10 indivíduos: Grupo Gagueira com Transtorno do Processamento Auditivo (GGTPA) e Grupo Gagueira (GG) sem alteração de processamento auditivo central. Os procedimentos foram: avaliação da fluência com retroalimentação auditiva habitual (RAH) e atrasada (RAA), e avaliação da gravidade da gagueira e do processamento auditivo central (PAC). O software Fono Tools foi utilizado para provocar o atraso de 100 milissegundos na retroalimentação auditiva. O teste dos Postos Sinalizados de Wilcoxon foi utilizado na análise intragrupos, e o teste de Mann-Whitney, na análise intergrupos. Resultados A RAA ocasionou no GG redução estatisticamente significante: no escore da frequência das disfluências típicas da gagueira na análise do Instrumento de Gravidade da Gagueira, na quantidade de bloqueios e de repetições de palavras monossilábicas, e na frequência de disfluências típicas da gagueira de duração. O atraso na retroalimentação auditiva não provocou efeitos estatisticamente significantes na fluência do GGTPA, grupo dos indivíduos com gagueira com alteração do PAC. Conclusão O efeito da retroalimentação auditiva atrasada na fala de indivíduos com gagueira foi diferente nos indivíduos com e sem alteração do processamento auditivo central, pois houve melhora da fluência apenas nos indivíduos sem alteração do PAC.

The role of auditory temporal cues in the fluency of stuttering adults

ABSTRACT Purpose: to compare the frequency of disfluencies and speech rate in spontaneous speech and reading in adults with and without stuttering in non-altered and delayed auditory feedback (NAF, DAF). Methods: participants were 30 adults: 15 with Stuttering (Research Group - RG), and 15 without stuttering (Control Group - CG). The procedures were: audiological assessment and speech fluency evaluation in two listening conditions, normal and delayed auditory feedback (100 milliseconds delayed by Fono Tools software). Results: the DAF caused a significant improvement in the fluency of spontaneous speech in RG when compared to speech under NAF. The effect of DAF was different in CG, because it increased the common disfluencies and the total of disfluencies in spontaneous speech and reading, besides showing an increase in the frequency of stuttering-like disfluencies in reading. The intergroup analysis showed significant differences in the two speech tasks for the two listening conditions in the frequency of stuttering-like disfluencies and in the total of disfluencies, and in the flows of syllable and word-per-minute in the NAF. Conclusion: the results demonstrated that delayed auditory feedback promoted fluency in spontaneous speech of adults who stutter, without interfering in the speech rate. In non-stuttering adults an increase occurred in the number of common disfluencies and total of disfluencies as well as reduction of speech rate in spontaneous speech and reading.

Increased Response to Altered Auditory Feedback in Dyslexia: A Weaker Sensorimotor Magnet Implied in the Phonological Deficit

PURPOSE

The purpose of this study was to examine whether developmental dyslexia (DD) is characterized by deficiencies in speech sensory and motor feedforward and feedback mechanisms, which are involved in the modulation of phonological representations.

METHOD

A total of 42 adult native speakers of Dutch (22 adults with DD; 20 participants who were typically reading controls) were asked to produce /bep/ while the first formant (F1) of the /e/ was not altered (baseline), increased (ramp), held at maximal perturbation (hold), and not altered again (after-effect). The F1 of the produced utterance was measured for each trial and used for statistical analyses. The measured F1s produced during each phase were entered in a linear mixed-effects model.

RESULTS

Participants with DD adapted more strongly during the ramp phase and returned to baseline to a lesser extent when feedback was back to normal (after-effect phase) when compared with the typically reading group. In this study, a faster deviation from baseline during the ramp phase, a stronger adaptation response during the hold phase, and a slower return to baseline during the after-effect phase were associated with poorer reading and phonological abilities.

CONCLUSION

The data of the current study are consistent with the notion that the phonological deficit in DD is associated with a weaker sensorimotor magnet for phonological representations.

Prolongamentos na fala de adultos com e sem gagueira

RESUMO Objetivo: realizar uma análise quantitativa e qualitativa dos prolongamentos de adultos com e sem gagueira. Métodos: os participantes foram divididos em: Grupo de Pesquisa (GP, 15 adultos com gagueira) e Grupo Controle (GC, 15 fluentes). Os procedimentos utilizados foram: avaliação da fluência, Instrumento de Gravidade da Gagueira e análises quantitativa e qualitativa dos prolongamentos. Resultados: GP mostrou maior número de prolongamentos não hesitativos, enquanto que GC mostrou maior ocorrência de prolongamentos hesitativos em relação ao total das disfluências. Prolongamentos não hesitativos ocorreram com maior frequência na palavra inicial e monossilábica, bem como na posição medial da frase para GP. Em relação à tensão muscular e duração, observou-se diferença apenas para a tensão muscular nos prolongamentos não hesitativos com maior média de ocorrência para GP. Conclusão: os prolongamentos não hesitativos ocorreram com maior frequência no GP, nas palavras iniciais, monossílabos e na posição medial da frase. Qualitativamente a tensão muscular foi uma característica típica dos prolongamentos não hesitativos no GP. Com relação aos prolongamentos hesitativos houve semelhança entre os adultos dos dois grupos quanto à frequência em relação ao total da fala, a posição dos prolongamentos nas palavras e nas frases e nos aspectos qualitativos, relacionados a tensão muscular e duração.

Non-pharmacological treatments for stuttering in children and adults: a systematic review and evaluation of clinical effectiveness, and exploration of barriers to successful outcomes

BACKGROUND

Despite many years of research, there is no certainty regarding the cause of stuttering. Although numerous interventions have been developed, a broad-based systematic review across all forms of intervention for adults and children was needed including views and perceptions of people who stutter.

OBJECTIVE

The aims of the study were to report the clinical effectiveness of interventions for people who stutter (or clutter), to examine evidence regarding the views of people who stutter and the views of professionals regarding interventions.

DATA SOURCES

A systematic review of quantitative and qualitative literature was carried out between August 2013 and April 2014. The following electronic databases were searched: (1) MEDLINE, (2) EMBASE, (3) The Cochrane Library (including The Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, Health Technology Assessment Database and NHS Economic Evaluations Database), (4) PsycINFO, (5) Science Citation Index, (6) Social Science Citation Index, (7) Cumulative Index to Nursing and Allied Health Literature, (8) ASSIA, (9) Linguistics and Language Behavior Abstracts, (10) Sociological Abstracts and (11) the EPPI Centre. Reference lists of included papers and other reviews were screened and also key journals in the subject area were hand-searched.

REVIEW METHODS

The searches aimed to identify (1) evidence of clinical effectiveness in populations of pre-school children, school-aged children, adolescents and adults, and (2) data relating to perceptions of barriers and facilitators to intervention clinical effectiveness among staff and people who stutter. A metasynthesis of the two linked elements via development of a conceptual model was also carried out to provide further interpretation of the review findings.

RESULTS

A systematic search of the literature identified a large number of potentially relevant studies. Of these, 111 studies examining the clinical effectiveness of interventions, 25 qualitative papers and one mixed-methods paper met the criteria for inclusion in this review. Review of the effectiveness literature indicated evidence of positive outcomes across all types of interventions. Virtually all evidence we identified reported at least some positive effect for some participants. However, there was evidence of considerable individual variation in outcome for study participants. The qualitative literature highlighted the need for programmes to be tailored to individual need with variation at the levels of the intervention, the individual and interpersonal/social elements. Metasynthesis of the data highlighted the complexity of elements that need to be considered in evaluation of long-term impacts following stuttering interventions.

LIMITATIONS

Around two-thirds of the studies were considered to be at higher risk of bias. The heterogeneous nature and variability in outcomes meant that we were unable to complete a meta-analysis.

CONCLUSIONS

Although much of the evidence we identified was from studies at risk of bias, it is suggested that most available interventions for stuttering may be of benefit to at least some people who stutter. There is a requirement for greater clarity regarding what the core outcomes following stuttering intervention should be and also enhanced understanding of the process whereby interventions effect change. Further analysis of those for whom interventions have not produced a significant benefit may provide additional insights into the complex intervention-outcomes pathway.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013004861.

Comparação da leitura de escolares com gagueira em duas condições de escuta: habitual e atrasada

RESUMO Objetivo: comparar os efeitos imediatos do atraso na retroalimentação auditiva na tarefa de leitura oral em escolares com gagueira do desenvolvimento persistente. Métodos: estudo aprovado pelo Comitê de Ética da Instituição (n°0714/2013). Participaram 16 escolares, com idade de 8 a 17 anos, sendo 11 do gênero masculino e 5 do feminino, separados em dois Grupos Experimentais (GE1 e GE2) de 8 participantes cada; o GE1 composto de participantes com gagueira moderada e o GE2 com gagueira grave ou muito grave. Os procedimentos utilizados foram: avaliação audiológica, avaliação da fluência na fala espontânea e avaliação da fluência na leitura oral em duas condições de escuta: com Retroalimentação Auditiva Habitual - RAH e atrasada - RAA. O software Fono Tools junto com o Adaptador Andrea PureAudio USB-AS e microfone auricular Karsect HT-2 foram utilizados para provocar o efeito da RAA e gravar a fala. Resultados: o efeito da retroalimentação auditiva atrasada ocasionou redução das disfluências típicas da gagueira em ambos os grupos, porém a frequência de outras disfluências aumentou no grupo de gagueira moderada e diminuiu no grupo com gagueira grave/muito grave e, desta forma, o total de disfluências apresentou uma diminuição mais significativa no GE2. A diferença foi estatisticamente significante apenas na comparação intergrupos das disfluências típicas da gagueira, na situação de retroalimentação auditiva habitual. Conclusões: o atraso na retroalimentação auditiva não ocasionou efeitos significantes na leitura em ambos os grupos, entretanto há uma tendência do efeito ser considerado positivo para o grupo com gagueira grave/muito grave.

The state of the art in non-pharmacological interventions for developmental stuttering. Part 1: a systematic review of effectiveness

BACKGROUND

The growing range of available treatment options for people who stutter presents a challenge for clinicians, service managers and commissioners, who need to have access to the best available treatment evidence to guide them in providing the most appropriate interventions. While a number of reviews of interventions for specific populations or a specific type of intervention have been carried out, a broad-based systematic review across all forms of intervention for adults and children was needed to provide evidence to underpin future guidelines, inform the implementation of effective treatments and identify future research priorities.

AIMS

To identify and synthesize the published research evidence on the clinical effectiveness of the broad range of non-pharmacological interventions for the management of developmental stuttering.

METHODS & PROCEDURES

A systematic review of the literature reporting interventions for developmental stuttering was carried out between August 2013 and April 2014. Searches were not limited by language or location, but were restricted by date to studies published from 1990 onwards. Methods for the identification of relevant studies included electronic database searching, reference list checking, citation searching and hand searching of key journals. Appraisal of study quality was performed using a tool based on established criteria for considering risk of bias. Due to heterogeneity in intervention content and outcomes, a narrative synthesis was completed.

MAIN CONTRIBUTION

The review included all available types of intervention and found that most may be of benefit to at least some people who stutter. There was evidence, however, of considerable individual variation in response to these interventions. The review indicated that effects could be maintained following all types of interventions (although this was weakest with regard to feedback and technology interventions).

CONCLUSIONS

This review highlights a need for greater consensus with regard to the key outcomes used to evaluate stuttering interventions, and also a need for enhanced understanding of the process whereby interventions effect change. Further analysis of the variation in effectiveness for different individuals or groups is needed in order to identify who may benefit most from which intervention.