Deficit or Difference? Effects of Altered Auditory Feedback on Speech Fluency and Kinematic Variability in Adults Who Stutter

Purpose The purpose of this study was to test whether adults who stutter (AWS) display a different range of sensitivity to delayed auditory feedback (DAF). Two experiments were conducted to assess the fluency of AWS under long-latency DAF and to test the effect of short-latency DAF on speech kinematic variability in AWS. Method In Experiment 1, 15 AWS performed a conversational speaking task under nonaltered auditory feedback and 250-ms DAF. The rates of stuttering-like disfluencies, other disfluencies, and speech errors and articulation rate were compared. In Experiment 2, 13 AWS and 15 adults who do not stutter (AWNS) read three utterances under four auditory feedback conditions: nonaltered auditory feedback, amplified auditory feedback, 25-ms DAF, and 50-ms DAF. Across-utterance kinematic variability (spatiotemporal index) and within-utterance variability (percent determinism and stability) were compared between groups. Results In Experiment 1, under 250-ms DAF, the rate of stuttering-like disfluencies and speech errors increased significantly, while articulation rate decreased significantly in AWS. In Experiment 2, AWS exhibited higher kinematic variability than AWNS across the feedback conditions. Under 25-ms DAF, the spatiotemporal index of AWS decreased significantly compared to the other feedback conditions. AWS showed lower overall percent determinism than AWNS, but their percent determinism increased under 50-ms DAF to approximate that of AWNS. Conclusions Auditory feedback manipulations can alter speech fluency and kinematic variability in AWS. Longer latency auditory feedback delays induce speech disruptions, while subtle auditory feedback manipulations potentially benefit speech motor control. Both AWS and AWNS are susceptible to auditory feedback during speech production, but AWS appear to exhibit a distinct continuum of sensitivity.

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Investigation of the effect of Delayed Auditory Feedback and transcranial Direct Current Stimulation (DAF-tDCS) treatment for the enhancement of speech fluency in adults who stutter: a Randomized Controlled Trial

10.21203/rs.3.rs-29391/v1 ◽

2020 ◽

Author(s):

Narges Moein ◽

Reyhane Mohamadi ◽

Reza Rostami ◽

Michael Nitsche ◽

Reza Zomorrodi ◽

...

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Auditory Feedback ◽

Intervention Group ◽

Control Group ◽

Anodal Tdcs ◽

Delayed Auditory Feedback ◽

Direct Current Stimulation ◽

Speech Fluency ◽

Adults Who Stutter

Abstract Background: With a population prevalence of one percent, stuttering is among the main speech pathology-related topics of research. Adults who stutter may benefit from transcranial direct current stimulation (tDCS) as an adjunctive intervention for enhancing speech fluency. In this study, Delayed Auditory Feedback (DAF) was combined with tDCS applied over the superior temporal gyrus. It was anticipated that intervention caused improvements of speech fluency become more stable.Methods: A randomized, double-blind, sham-controlled clinical trial was conducted to investigate the effectiveness of intervention in enhancing speech fluency. Fifty participants were randomly allocated the intervention or control group. In the intervention group, participants received DAF combined with anodal tDCS, while the control group was exposed to sham tDCS simultaneously with DAF. Each subject participated in six intervention sessions. Speech fluency was assessed before intervention as baseline, as well as immediately, one week and six weeks after intervention.Results: In the intervention group, the percentage of stuttered syllables was significantly reduced immediately, one week and six weeks after the intervention, as compared with the control group. The scores of the Stuttering Severity Instrument, also showed a significant reduction in the intervention group compared with the control group. No significant difference was found in the Overall Assessment of the Speaker’s Experience of Stuttering questionnaire scores between the two patient two groups after intervention.Conclusion: The results of this study propose anodal tDCS as an adjunctive method to increase speech fluency in stuttering for a prolonged time course after intervention, when combined with fluency therapy.Trial registration: This trial was registered in ClinicalTrial.gov before recruiting the subjects. The registration number is NCT03990168 and the date of registration is June 18, 2019. https://clinicaltrials.gov/ct2/show/NCT03990168

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Investigation of the effect of Delayed Auditory Feedback and transcranial Direct Current Stimulation (DAF-tDCS) treatment for the enhancement of speech fluency in adults who stutter: a Randomized Controlled Trial

10.21203/rs.3.rs-29391/v2 ◽

2020 ◽

Author(s):

Narges Moein ◽

Reyhane Mohamadi ◽

Reza Rostami ◽

Michael Nitsche ◽

Reza Zomorrodi ◽

...

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Auditory Feedback ◽

Intervention Group ◽

Control Group ◽

Anodal Tdcs ◽

Delayed Auditory Feedback ◽

Direct Current Stimulation ◽

Speech Fluency ◽

Adults Who Stutter

Abstract Background: With a population prevalence of one percent, stuttering is among the main speech pathology-related topics of research. Adults who stutter may benefit from transcranial direct current stimulation (tDCS) as an adjunctive intervention for enhancing speech fluency. In this study, Delayed Auditory Feedback (DAF) was combined with tDCS applied over the superior temporal gyrus. It was anticipated that the combined intervention cause improvements in speech fluency.Methods: A randomized, double-blind, sham-controlled clinical trial was conducted to investigate the effectiveness of intervention in enhancing speech fluency. Fifty participants were randomly allocated to the intervention or control group. In the intervention group, participants received DAF combined with anodal tDCS, while the control group was exposed to sham tDCS simultaneously with DAF. Each subject participated in six intervention sessions. Speech fluency was assessed as the baseline, before intervention as well as immediately, one week and six weeks after intervention. Results: In the intervention group, the percentage of stuttered syllables was significantly reduced immediately, one week and six weeks after the intervention, as compared with the control group. The scores of the Stuttering Severity Instrument, also showed a significant reduction in the intervention group compared with the control group. No significant difference was found in the Overall Assessment of the Speaker’s Experience of Stuttering questionnaire scores between the two groups after intervention. Conclusion: The results of this study propose anodal tDCS as an adjunctive method to increase speech fluency in stuttering for a prolonged time course after intervention, when combined with fluency therapy.Trial registration: This trial was registered in ClinicalTrial.gov before recruiting the subjects. The registration number is NCT03990168 and the date of registration is June 18, 2019. https://clinicaltrials.gov/ct2/show/NCT03990168

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Delayed Auditory Feedback and Transcranial Direct Current Stimulation Treatment for the Enhancement of Speech Fluency in Adults Who Stutter: Protocol for a Randomized Controlled Trial

JMIR Research Protocols ◽

10.2196/16646 ◽

2020 ◽

Vol 9 (4) ◽

pp. e16646

Author(s):

Narges Moein ◽

Reyhane Mohamadi ◽

Reza Rostami ◽

Michael Nitsche ◽

Reza Zomorrodi ◽

...

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Auditory Feedback ◽

Intervention Group ◽

Control Group ◽

Delayed Auditory Feedback ◽

Direct Current Stimulation ◽

Speech Fluency ◽

Adults Who Stutter

Background Stuttering is a complex speech disorder that affects speech fluency. Recently, it has been shown that noninvasive brain stimulation may be useful to enhance the results of fluency interventions in adults who stutter. Delayed auditory feedback (DAF) is a method to enhance speech fluency in individuals who stutter. Adjunctive interventions are warranted to enhance the efficacy of this intervention. Objective Individuals who stutter have pathological activation patterns in the primary and secondary auditory areas. Consequently, in this study, we hypothesize that stimulation of these areas might be promising as an adjunctive method to fluency training via DAF to enhance speech therapy success in individuals with a stutter. We will systematically test this hypothesis in this study. Methods This study is designed as a randomized, double-blind, sham-controlled clinical trial. All participants will receive DAF. The intervention group will additionally receive real transcranial direct current stimulation, while the control group will be exposed to sham stimulation. The assignment of the participants to one of these groups will be randomized. Before starting the treatment program, 2 preintervention assessments will be conducted to determine the severity of stuttering. Once these assessments are completed, each subject will participate in 6 intervention sessions. Postintervention assessments will be carried out immediately and 1 week after the last intervention session. Subsequently, to explore the long-term stability of the treatment results, the outcome parameters will be obtained in follow-up assessments 6 weeks after the treatment. The primary outcome measurement—the percentage of stuttered syllables—will be calculated in pre-, post-, and follow-up assessments; the secondary outcomes will be the scores of the following questionnaires: the Stuttering Severity Instrument–Fourth Edition and the Overall Assessment of the Speaker’s Experience of Stuttering. Results This protocol was funded in 2019 and approved by the Research Ethics Committee of the Iran University of Medical Sciences in June 2019. Data collection started in October 2019. As of February 2020, we have enrolled 30 participants. We expect data analysis to be completed in April 2020, and results will be published in summer 2020. Conclusions We anticipate that this study will show an adjunctive effect of transcranial direct current stimulation, when combined with DAF, on stuttering. This should include not only a reduction in the percentage of stuttered syllables but also improved physical behavior and quality of life in adults who stutter. Trial Registration ClinicalTrial.gov NCT03990168; https://clinicaltrials.gov/ct2/show/NCT03990168 International Registered Report Identifier (IRRID) DERR1-10.2196/16646

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Delayed Auditory Feedback and Transcranial Direct Current Stimulation Treatment for the Enhancement of Speech Fluency in Adults Who Stutter: Protocol for a Randomized Controlled Trial (Preprint)

10.2196/preprints.16646 ◽

2019 ◽

Author(s):

Narges Moein ◽

Reyhane Mohamadi ◽

Reza Rostami ◽

Michael Nitsche ◽

Reza Zomorrodi ◽

...

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Auditory Feedback ◽

Intervention Group ◽

Control Group ◽

Delayed Auditory Feedback ◽

Direct Current Stimulation ◽

Speech Fluency ◽

Adults Who Stutter

BACKGROUND Stuttering is a complex speech disorder that affects speech fluency. Recently, it has been shown that noninvasive brain stimulation may be useful to enhance the results of fluency interventions in adults who stutter. Delayed auditory feedback (DAF) is a method to enhance speech fluency in individuals who stutter. Adjunctive interventions are warranted to enhance the efficacy of this intervention. OBJECTIVE Individuals who stutter have pathological activation patterns in the primary and secondary auditory areas. Consequently, in this study, we hypothesize that stimulation of these areas might be promising as an adjunctive method to fluency training via DAF to enhance speech therapy success in individuals with a stutter. We will systematically test this hypothesis in this study. METHODS This study is designed as a randomized, double-blind, sham-controlled clinical trial. All participants will receive DAF. The intervention group will additionally receive real transcranial direct current stimulation, while the control group will be exposed to sham stimulation. The assignment of the participants to one of these groups will be randomized. Before starting the treatment program, 2 preintervention assessments will be conducted to determine the severity of stuttering. Once these assessments are completed, each subject will participate in 6 intervention sessions. Postintervention assessments will be carried out immediately and 1 week after the last intervention session. Subsequently, to explore the long-term stability of the treatment results, the outcome parameters will be obtained in follow-up assessments 6 weeks after the treatment. The primary outcome measurement—the percentage of stuttered syllables—will be calculated in pre-, post-, and follow-up assessments; the secondary outcomes will be the scores of the following questionnaires: the Stuttering Severity Instrument–Fourth Edition and the Overall Assessment of the Speaker’s Experience of Stuttering. RESULTS This protocol was funded in 2019 and approved by the Research Ethics Committee of the Iran University of Medical Sciences in June 2019. Data collection started in October 2019. As of February 2020, we have enrolled 30 participants. We expect data analysis to be completed in April 2020, and results will be published in summer 2020. CONCLUSIONS We anticipate that this study will show an adjunctive effect of transcranial direct current stimulation, when combined with DAF, on stuttering. This should include not only a reduction in the percentage of stuttered syllables but also improved physical behavior and quality of life in adults who stutter. CLINICALTRIAL ClinicalTrial.gov NCT03990168; https://clinicaltrials.gov/ct2/show/NCT03990168 INTERNATIONAL REGISTERED REPORT DERR1-10.2196/16646

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Consistency influences altered auditory feedback processing

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021819838939 ◽

2019 ◽

Vol 72 (10) ◽

pp. 2371-2379 ◽

Cited By ~ 3

Author(s):

Matthias K Franken ◽

Daniel J Acheson ◽

James M McQueen ◽

Peter Hagoort ◽

Frank Eisner

Keyword(s):

Motor Control ◽

Speech Production ◽

Auditory Feedback ◽

Speech Motor Control ◽

Short Term ◽

Feedback Processing ◽

Motor Commands ◽

Consistent Condition ◽

Consistency Effect ◽

Speech Motor

Previous research on the effect of perturbed auditory feedback in speech production has focused on two types of responses. In the short term, speakers generate compensatory motor commands in response to unexpected perturbations. In the longer term, speakers adapt feedforward motor programmes in response to feedback perturbations, to avoid future errors. The current study investigated the relation between these two types of responses to altered auditory feedback. Specifically, it was hypothesised that consistency in previous feedback perturbations would influence whether speakers adapt their feedforward motor programmes. In an altered auditory feedback paradigm, formant perturbations were applied either across all trials (the consistent condition) or only to some trials, whereas the others remained unperturbed (the inconsistent condition). The results showed that speakers’ responses were affected by feedback consistency, with stronger speech changes in the consistent condition compared with the inconsistent condition. Current models of speech-motor control can explain this consistency effect. However, the data also suggest that compensation and adaptation are distinct processes, which are not in line with all current models.

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The Establishment, Transfer, and Maintenance of Fluent Speech in 50 Stutterers Using Delayed Auditory Feedback and Operant Procedures

Journal of Speech and Hearing Disorders ◽

10.1044/jshd.3901.03 ◽

1974 ◽

Vol 39 (1) ◽

pp. 3-10 ◽

Cited By ~ 60

Author(s):

Bruce P. Ryan ◽

Barbara Van Kirk

Keyword(s):

Detailed Analysis ◽

Auditory Feedback ◽

Rehabilitation Center ◽

Delayed Auditory Feedback ◽

Fluent Speech ◽

Speech Fluency ◽

The Past ◽

Clinical Program

Operant speech fluency techniques are being used in a clinical program in a rehabilitation center to treat people who stutter. Establishment, transfer, and maintenance programs are used. Delayed auditory feedback is commonly employed to produce the initial fluent speech. From more than 200 clients seen over the past four years, 50 recent clients were selected for a detailed analysis. The results indicate that the programs are effective in helping people of varying ages and stuttering severity to speak fluently. This was accomplished in relatively short periods (approximately 20 hours of therapy). The fluent speech of the clients has transferred to their environment and checks indicate that it has been maintained.

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Abnormal Speech Motor Control in Individuals with 16p11.2 Deletions

10.1101/165316 ◽

2017 ◽

Author(s):

Carly Demopoulos ◽

Hardik Kothare ◽

Danielle Mizuiri ◽

Jennifer Henderson-Sabes ◽

Brieana Fregeau ◽

...

Keyword(s):

Motor Control ◽

Auditory Feedback ◽

Spectral Peak ◽

Motor Deficits ◽

Speech Motor Control ◽

Sensorimotor Adaptation ◽

Speech And Language ◽

Vowel Production ◽

Identity Changes ◽

Speech Motor

AbstractSpeech and motor deficits are highly prevalent (>70%) in individuals with the 600 kb BP4-BP5 16p11.2 deletion; however, the mechanisms that drive these deficits are unclear, limiting our ability to target interventions and advance treatment. This study examined fundamental aspects of speech motor control in participants with the 16p11.2 deletion. To assess capacity for control of voice, we examined how accurately and quickly subjects changed the pitch of their voice within a trial to correct for a transient perturbation of the pitch of their auditory feedback. When compared to sibling controls, 16p11.2 deletion carriers show an over-exaggerated pitch compensation response to unpredictable mid-vocalization pitch perturbations. We also examined sensorimotor adaptation of speech by assessing how subjects learned to adapt their sustained productions of formants (speech spectral peak frequencies important for vowel identity), in response to consistent changes in their auditory feedback during vowel production. Deletion carriers show reduced sensorimotor adaptation to sustained vowel identity changes in auditory feedback. These results together suggest that 16p11.2 deletion carriers have fundamental impairments in the basic mechanisms of speech motor control and these impairments may partially explain the deficits in speech and language in these individuals.

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