Speech Sequencing Therapies for Stuttering

Recruiting at 2 trial locations

Overseen By Barbara Holland

Age: Any Age

Sex: Any

Trial Phase: Academic

Sponsor: Boston University Charles River Campus

Must not be taking: Speech medications

Disqualifiers: Seizures, Claustrophobia, Implants, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 7

2 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to better understand how the brain plans and produces speech, focusing on individuals who stutter or have speech disorders like primary progressive aphasia. Researchers will use brain imaging and non-invasive techniques, such as Transcranial Direct Current Stimulation (tDCS), to compare speech effects in these groups with those having typical speech patterns. Participants will learn new word sounds and sequences to test how the brain processes speech. The trial seeks native English speakers with either persistent stuttering, typical speech, or primary progressive aphasia. As an unphased study, this trial offers a unique opportunity to contribute to groundbreaking research in speech disorders.

Do I need to stop my current medications to join the trial?

If you have primary progressive aphasia (PPA), you cannot participate if you are taking medications that affect speech or language. For others, the protocol does not specify if you need to stop taking your current medications.

What prior data suggests that these speech sequencing therapies are safe?

Research has shown that transcranial direct current stimulation (tDCS) is generally safe. Studies indicate that people tolerate tDCS well, with only minor side effects such as slight skin irritation or mild tingling at the electrode sites. Serious side effects are rare.

For learning new speech sounds and unfamiliar words, the emphasis is on practice and learning. No evidence suggests major safety concerns with these activities. Practicing new speech patterns is considered safe. Overall, researchers have used the treatments in this study in other research, demonstrating good safety records. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the Speech Sequencing Therapies for Stuttering trial because it explores innovative ways to improve speech fluency using combinations of novel sounds and advanced brain stimulation techniques. Unlike traditional speech therapy, which typically involves practicing speech patterns, this trial delves into learning non-native phoneme combinations and novel multisyllabic nonwords. It also uses transcranial direct current stimulation (tDCS) to potentially enhance learning by targeting specific brain areas involved in speech. Additionally, by employing functional magnetic resonance imaging (fMRI), the trial aims to understand the brain activity associated with these new learning methods. This approach could pave the way for more effective and tailored treatments for stuttering and related speech disorders.

What evidence suggests that this trial's treatments could be effective for stuttering?

Research shows that transcranial direct current stimulation (tDCS) combined with specific speech exercises can help adults who stutter speak more fluently. In this trial, some participants will receive anodal tDCS, while others will receive sham tDCS as a control. Studies have found that tDCS can noticeably reduce the frequency and severity of stuttering.

Research has shown that people can learn new sounds in a language with practice, even if they are initially difficult to distinguish. This trial includes arms where participants will engage in learning non-native phoneme combinations, which may improve speech organization in people who stutter.

For learning new, made-up words with many syllables, studies have found that people who stutter might struggle to repeat these words accurately. This trial will test multisyllabic learning in both children and adults, suggesting that focused practice might improve their ability to manage these speech patterns. ^{1 6 7 8 9}

Who Is on the Research Team?

Frank H Guenther, PhD

Principal Investigator

Boston University

Soo-Eun Chang, PhD

Principal Investigator

University of Michigan

Are You a Good Fit for This Trial?

This trial is for native American English speakers with limited second language exposure. It includes children who pass a hearing test, adults without neurological issues (except stuttering), and those diagnosed with primary progressive aphasia by MGH-FTD. Excluded are individuals with contraindications to MRI or tDCS, certain medication use in PPA patients, severe cognitive impairment, and outside the age range for child participants.

Inclusion Criteria

My hearing is good at specific test frequencies.

I am healthy with no history of brain, speech, or hearing problems, except for stuttering.

Only native speakers of American English with limited exposure to a second language will be recruited

Exclusion Criteria

I am not on medications that could affect my speech or language.

You cannot participate in MRI studies if you have had seizures, severe claustrophobia, metal implants in your body, or if you are pregnant.

You cannot participate if you have metal implants in your head, certain medical devices in your body, a history of seizures, significant scalp injuries, or if you are pregnant.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Training

Participants undergo training sessions to learn novel speech sequences using various methods such as tDCS and fMRI

2-3 days

6-8 training sessions

Intervention

Functional MRI and other assessments are conducted to measure brain activity and speech performance

1 day

1 fMRI session

Follow-up

Participants are monitored for changes in speech performance and brain activity post-intervention

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Anodal tDCS
• Learning of non-native phoneme combinations: 1 training session
• Learning of non-native phoneme combinations: 6 training sessions
• Learning of non-native phoneme combinations: 8 training sessions
• Learning of novel multisyllabic nonwords
• Sham tDCS

Trial Overview

The study investigates brain mechanisms in speech motor planning through experiments involving speech production tasks, functional MRI scans, and non-invasive brain stimulation like sham and anodal tDCS. Participants will learn new phoneme combinations or multisyllabic nonwords across multiple sessions to help understand these processes in people with stuttering or neurodegenerative speech disorders.

How Is the Trial Designed?

Group I: Sub-syllabic learning in PPA Experimental Treatment 1 Intervention

30 adults with primary progressive aphasia (PPA) will participate in this arm. Subjects will learn novel 1-syllable nonsense words formed by non-native phoneme combinations during 8 training sessions over 2 days. Following training, subjects will complete a behavioral test to compare their performance on the words learned during training with a set of unfamiliar words also formed by non-native phoneme combinations.

Group II: Sub-syllabic learning and fMRI Experimental Treatment 1 Intervention

60 adults with neurotypical speech development will participate in this arm. Subjects will learn novel 1-syllable nonsense words formed by non-native phoneme combinations during 6 training sessions over 2 days. Following training, subjects will participate in a functional magnetic resonance imaging (fMRI) session on a third day to measure brain activity associated with producing the words learned during training and with a set of unfamiliar words also formed by non-native phoneme combinations.

Group III: Sub-syllabic learning and anodal tDCS of inferior frontal sulcus Experimental Treatment 2 Interventions

35 adults with neurotypical speech development will participate in this arm. Subjects will learn novel 1-syllable nonsense words formed by non-native phoneme combinations. During the training, anodal transcranial direct current stimulation (tDCS) will be applied to the the subject's left inferior frontal sulcus.

Group IV: Sub-syllabic learning and anodal tDCS of cerebellum Experimental Treatment 2 Interventions

35 adults with neurotypical speech development will participate in this arm. Subjects will learn novel 1-syllable words formed by non-native phoneme combinations. During the training, continuous anodal transcranial direct current stimulation (tDCS) will be applied to the the subject's right cerebellum.

Group V: Multisyllabic learning in children Experimental Treatment 1 Intervention

45 children with persistent developmental stuttering (CWS) and 45 children with neurotypical speech development (CNS) will participate in this arm. Subjects will learn nonsense words formed by novel combinations of 2 syllables that are legal in American English during 6 training sessions over 2 days. Behavioral measures extracted from the data will be used to compare performance before and after training and across the CWS and CNS participants.

Group VI: Multisyllabic learning and fMRI in adults Experimental Treatment 1 Intervention

30 adults persistent developmental stuttering (AWS) and 30 adults with neurotypical speech development (ANS) will participate in this arm. Subjects will learn nonsense words formed by novel combinations of 3 syllables that are legal in American English during 6 training sessions over 2 days. Following training, subjects will participate in a functional magnetic resonance imaging (fMRI) session on a third day to measure brain activity associated with producing the words formed by pairing 2 learned 3-syllable strings learned during training and those formed by pairing 2 unfamiliar 3-syllable strings. Behavioral measures extracted from the data will be used to compare performance before and after training and across the AWS and ANS participants.

Group VII: Sub-syllabic learning and sham tDCS Placebo Group 2 Interventions

35 adults with neurotypical speech development will participate in this arm. Subjects will learn novel 1-syllable words formed by non-native phoneme combinations. During training, Sham transcranial direct current stimulation stimulation (tDCS) will be delivered to the subject's brain.

Who Is Running the Clinical Trial?

Boston University Charles River Campus

Lead Sponsor

Trials

125

Recruited

14,100+

University of Michigan

Collaborator

Trials

1,891

Recruited

6,458,000+

Massachusetts General Hospital

Collaborator

Trials

3,066

Recruited

13,430,000+

National Institute on Deafness and Other Communication Disorders (NIDCD)

Collaborator

Trials

377

Recruited

190,000+

Published Research Related to This Trial

The study demonstrated that practicing phoneme sequences with non-native consonant clusters improved utterance duration for new syllables containing those clusters, suggesting that our brains efficiently store these clusters as 'chunks' to enhance speech production.

However, practicing whole syllables led to greater reductions in error rates, indicating that while consonant clusters are important for phonological memory, syllables play a crucial role in the motor programming of speech.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Chunking of phonological units in speech sequencing. Segawa, J., Masapollo, M., Tong, M., et al.[2020]

The Therapeutic Stuttering Summer-camp, involving participants aged 9 to 19, successfully reduced stuttering frequency from 22.2% to 9.5%, demonstrating a significant effect size of 1.29, indicating effective therapy.

Follow-up assessments and various measurement tools, including questionnaires and Goal Attainment Scaling, showed clear improvements in participants' handling of stuttering and fluency, confirming the therapy's efficacy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Treatment outcome study of the stuttering therapy summer camp 2000 for children and adolescents]. Baumeister, H., Caspar, F., Herziger, F.[2006]

Adults who stutter (AWS) demonstrated significantly lower accuracy in repeating nonwords as their length and complexity increased, indicating potential challenges in phonemic encoding and speech motor processes compared to control participants.

While both groups showed some practice effects, AWS did not retain improvements in speech kinematics across sessions, suggesting difficulties in skill acquisition and retention that may require further investigation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Practice and retention of nonwords in adults who stutter. Sasisekaran, J., Weisberg, S.[2021]

Nonspeech oral motor treatments (NSOMTs) are methods aimed at improving oral muscle function in children with developmental speech sound disorders, but their effectiveness is highly questionable.

Current research does not provide substantial evidence to support the use of NSOMTs as effective interventions for these speech disorders, raising concerns about their theoretical basis and clinical application.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Nonspeech oral motor treatment issues related to children with developmental speech sound disorders. Ruscello, DM.[2008]

In two studies involving nine people who stutter (PWS) and nine fluent speakers (PNS), significant differences were found in the speed of sequence skill learning, indicating that PWS may struggle more in the early stages of learning sequencing tasks compared to PNS.

The studies measured performance through finger tapping and reading nonsense syllables, revealing that PWS had slower reaction times and differences in retention and transfer of skills, which could inform future interventions for improving speech fluency.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Speech and nonspeech sequence skill learning in adults who stutter. Smits-Bandstra, S., De Nil, LF., Saint-Cyr, JA.[2015]

Both intensive (16 sessions over 4 days) and spaced (2 sessions per week for 8 weeks) fluency training formats significantly reduced stuttering frequency and improved speaking rate and communication attitudes in 20 adult and adolescent participants.

Both treatment formats were equally effective, but the maintenance of improvements varied across different speaking situations, indicating that tailored training may be necessary for specific contexts.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Relative efficacy of intensive and spaced behavioral treatment of stuttering. James, JE., Ricciardelli, LA., Hunter, CE., et al.[2017]

Fluency shaping (FS) and stuttering management (SM) are both evidence-based treatments for developmental stuttering in adults, with FS focusing on treatment outcomes and SM on understanding the nature of stuttering events.

While neither treatment guarantees uniform success, strategies like self-management and modeling are effective in both approaches and should be further studied for their efficacy, potentially using cognitive behavior theory as a framework.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evidence-based treatment and stuttering--historical perspective. Prins, D., Ingham, RJ.[2022]

A modified stuttering therapy program for school-age children, which emphasized self-therapy and clearly defined targets, led to significantly greater perceived improvements in speech fluency compared to an earlier program.

Follow-up videotape samples supported the participants' perceptions of improvement, indicating that the changes in the therapy approach were effective in reducing stuttering severity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stutterers' perceptions of therapy improvement and of posttherapy regression: effects of certain program modifications. Prins, D.[2019]

The study found that trained speech patterns in stuttering can be reliably identified by experts, with over 80% agreement in their assessments, similar to how fluent and stuttered speech is evaluated.

Using modified time interval analysis, the research suggests that measuring trained speech patterns could enhance outcome studies in stuttering therapy, providing a more comprehensive understanding of fluency improvements.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Measurement of trained speech patterns in stuttering: interjudge and intrajudge agreement of experts by means of modified time-interval analysis. Alpermann, A., Huber, W., Natke, U., et al.[2013]

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