Brain Stimulation for Speech Improvement

Overseen By David Ostry

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Yale University

Must not be taking: Psychoactive medications

Disqualifiers: Epilepsy, Neurological disorders, Pregnancy, others

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

Compensation: Varies

Number of Visits: 1

330 Participants Needed

Trial Summary

What is the purpose of this trial?

The overall goal of this research is to test a new model of speech motor learning, whose central hypothesis is that learning and retention are associated with plasticity not only in motor areas of the brain but in auditory and somatosensory regions as well.

Will I have to stop taking my current medications?

The trial excludes participants who are taking psychoactive medications, so you may need to stop taking those if you are currently on them. The protocol does not specify about other types of medications.

What data supports the effectiveness of the treatment Adaptation in the clinical trial Brain Stimulation for Speech Improvement?

Research shows that non-invasive brain stimulation, like transcranial direct current stimulation (tDCS), can enhance speech adaptation by improving how the brain integrates auditory feedback into speech motor plans. Additionally, tDCS has been effective in improving speech and language outcomes in conditions like post-stroke aphasia, suggesting its potential benefit in speech improvement. ^{1 2 3 4 5}

Is brain stimulation for speech improvement generally safe for humans?

The study on noninvasive neurostimulation using transcranial direct current stimulation (tDCS) over the speech motor cortex suggests that this method can be safely used to enhance speech adaptation in humans. ^{1 6 7 8 9}

How does the treatment Adaptation differ from other treatments for speech improvement?

The treatment Adaptation uses noninvasive brain stimulation, specifically transcranial direct current stimulation (tDCS), to enhance speech motor learning by increasing the brain's ability to integrate auditory feedback into speech motor plans. This approach is unique because it directly targets the brain's speech motor cortex to improve speech production, unlike traditional speech therapies that may not involve direct brain stimulation. ^{1 10 11 12 13}

Research Team

David Ostry

Principal Investigator

Yale University

Eligibility Criteria

This trial is for right-handed individuals who speak fluent English, have normal hearing, and no speech or reading disabilities. It's not suitable for those with metal implants, neurostimulators, cochlear implants, a history of neurological disorders or concussion, on psychoactive medications, pregnant women, or anyone with certain heart devices.

Inclusion Criteria

I have normal hearing.

No speech disorder or reading disability

Fluent English speakers

Exclusion Criteria

Implanted neurostimulator

Metal in brain, skull, or spinal cord

Metal implants

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Learning and Adaptation

Participants perform learning tasks with altered auditory feedback and undergo cTBS or fMRI to assess speech motor learning and retention.

30 minutes per session

Multiple sessions (in-person)

Retention Assessment

Retention of learning is assessed 24 hours after initial learning tasks.

24 hours after learning

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after the retention assessment.

4 weeks

Treatment Details

Interventions

• Adaptation

Trial Overview The study is examining how the brain learns and retains speech. Participants will undergo fMRI scans and different types of brain stimulation (single pulse TMS and cTBS) to see how these affect learning new speaking skills.

Participant Groups

Group I: Speech Motor Learning and Retention Aim 3 Experimental Treatment 2 Interventions

Aim 3: Participants will have fMRI with behavioral measures of speech motor learning.

Group II: Speech Motor Learning and Retention Aim 2 Experimental Treatment 2 Interventions

Aim 2: Participants will perform learning tasks combined with shifted auditory feedback. Motor cortical excitability will be measured using single-pulse TMS to elicit motor evoked potentials.

Group III: Speech Motor Learning and Retention Aim 1 Experimental Treatment 2 Interventions

Aim 1: Participants will perform learning tasks while receiving altered/unaltered auditory feedback with cTBS applied to the appropriate area of the brain following learning. Retention of learning is assessed 24 hours later.

Who Is Running the Clinical Trial?

Yale University

Lead Sponsor

Trials

1,963

Recruited

3,046,000+

National Institute on Deafness and Other Communication Disorders (NIDCD)

Collaborator

Trials

377

Recruited

190,000+

Findings from Research

Anodal transcranial direct current stimulation (tDCS) over the speech motor cortex significantly increased the rate of sensorimotor adaptation in participants, suggesting a potential method to enhance speech motor control.

The study's computational modeling indicated that tDCS primarily improved the integration of auditory feedback into speech motor plans by increasing the feedforward learning rate, highlighting a mechanism for how neurostimulation can influence speech production.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Noninvasive neurostimulation of left ventral motor cortex enhances sensorimotor adaptation in speech production. Scott, TL., Haenchen, L., Daliri, A., et al.[2021]

Non-invasive brain stimulation techniques, particularly low-frequency rTMS and cathodal tDCS, can significantly improve naming accuracy in patients with post-stroke aphasia, as shown in a meta-analysis of nine trials with 215 participants, yielding a moderate effect size of 0.51.

The application of these techniques to the non-language dominant hemisphere may promote neural reorganization and reduce competition between brain hemispheres, suggesting a promising adjunct to conventional speech and language therapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Inhibitory non-invasive brain stimulation to homologous language regions as an adjunct to speech and language therapy in post-stroke aphasia: a meta-analysis. Otal, B., Olma, MC., Flöel, A., et al.[2022]

Low-frequency transcranial magnetic stimulation (LF-rTMS) is the most effective non-invasive brain stimulation method for reducing global severity of post-stroke aphasia, based on a meta-analysis of 69 randomized controlled trials involving 1670 patients.

For specific language tasks, dual-transcranial direct-current stimulation (dual-tDCS) is superior for improving naming and repetition, while both anodal-tDCS and dual-tDCS are more effective than LF-rTMS for enhancing spontaneous speech.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparative efficacy of non-invasive brain stimulation for post-stroke aphasia: A network meta-analysis and meta-regression of moderators. Ding, X., Zhang, S., Huang, W., et al.[2022]

In a study involving 30 participants with subacute aphasia after stroke, those who received real repetitive transcranial magnetic stimulation (rTMS) combined with speech therapy showed significant improvements in all 10 measures of basic linguistic skills and functional communication, compared to only 6 measures in the sham group.

This research indicates that combining rTMS with behavioral language therapy can effectively enhance communication abilities in patients with subacute aphasia, marking a promising advancement in rehabilitation strategies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Add-on Effects of Repetitive Transcranial Magnetic Stimulation on Subacute Aphasia Therapy: Enhanced Improvement of Functional Communication and Basic Linguistic Skills. A Randomized Controlled Study. Rubi-Fessen, I., Hartmann, A., Huber, W., et al.[2022]

A case study involving a child with cerebral palsy showed that combining transcranial direct current stimulation (tDCS) with integrative speech therapy led to significant improvements in speech, including an increase in the percentage of correct consonants and the ability to produce two- and three-syllable words.

The therapy involved two phases of tDCS targeting different brain areas, resulting in a notable increase in phoneme production, suggesting that tDCS can enhance the effectiveness of speech rehabilitation in children with speech impairments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Neuromodulation: A combined-therapy protocol for speech rehabilitation in a child with cerebral palsy. Lima, VLCC., Cosmo, C., Lima, KB., et al.[2022]

A new dataset was created from 10 participants, capturing intracranial EEG data from 1103 electrodes while they read individual words, providing high-resolution insights into the neural processes of speech production.

This dataset can be utilized to enhance our understanding of speech mechanisms and to advance technologies like speech Brain-Computer Interfaces and neuroprostheses, which could help individuals with speech impairments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dataset of Speech Production in intracranial.Electroencephalography. Verwoert, M., Ottenhoff, MC., Goulis, S., et al.[2022]

A wearable biofeedback device was developed to help patients with Parkinsonism improve their speech intensity outside of clinical settings, addressing a common challenge in speech therapy.

The study showed that patients were able to transfer significant improvements in their speech from the clinic to everyday situations while using the device, indicating its potential effectiveness for ongoing treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A microcomputer-based wearable biofeedback device to improve transfer of treatment in parkinsonian dysarthria. Rubow, R., Swift, E.[2019]

The Forbrain® device significantly improved voice quality measures, such as harmony and robustness, in participants during speech tasks, indicating its potential effectiveness in modulating speech.

The device appears to function as an altered auditory feedback tool, suggesting it could be beneficial in clinical speech therapy settings, although more research is needed to confirm its efficacy in specific clinical populations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Potential Effect of Forbrain as an Altered Auditory Feedback Device. Escera, C., López-Caballero, F., Gorina-Careta, N.[2019]

The study successfully recorded corticobulbar motor evoked potentials (CoMEPs) from vocal muscles in 22 out of 24 patients using transcranial electrical stimulation (TES) and direct cortical stimulation (DCS), demonstrating the reliability of this method for intraoperative monitoring.

The results indicate that TES can elicit bilateral responses in vocal muscles, with specific onset latencies, providing a valuable tool for assessing the functional integrity of neural pathways during surgical procedures.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Methodology for intraoperatively eliciting motor evoked potentials in the vocal muscles by electrical stimulation of the corticobulbar tract. Deletis, V., Fernandez-Conejero, I., Ulkatan, S., et al.[2022]

Using high-definition transcranial direct current stimulation (HD-tDCS) on the left superior temporal lobe showed that this area is crucial for talker adaptation, as stimulation disrupted the ability to process speech efficiently, especially in mixed-talker conditions.

Listeners processed speech faster when hearing a single talker compared to multiple talkers, and the context of connected speech helped reduce processing difficulties, but this benefit was diminished when the left superior temporal lobe was stimulated.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Noninvasive neurostimulation of left temporal lobe disrupts rapid talker adaptation in speech processing. Choi, JY., Perrachione, TK.[2023]

Anodal transcranial direct current stimulation (tDCS) of the inferior parietal lobe (IPL) significantly enhanced motor adaptation in healthy adults when they experienced altered auditory feedback, leading to a 10% reduction in their vowel production frequency.

The study suggests that while anodal tDCS can improve speech motor learning and perceptual representation, cathodal tDCS did not produce similar benefits, indicating that enhancing cortical excitability is crucial for adaptive learning in speech tasks.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Modulation of Speech Motor Learning with Transcranial Direct Current Stimulation of the Inferior Parietal Lobe. Deroche, MLD., Nguyen, DL., Gracco, VL.[2020]

A study using behavioral and fMRI experiments shows that the right hemisphere of the brain is primarily responsible for processing spectral features of auditory feedback during speech, while the left hemisphere is more involved in processing temporal features.

This research highlights that effective speech production relies on both hemispheres of the brain, each contributing differently to how we control and adapt our speech based on auditory feedback.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Differential contributions of the two cerebral hemispheres to temporal and spectral speech feedback control. Floegel, M., Fuchs, S., Kell, CA.[2021]

Bilateral transcranial direct current stimulation (tDCS) of the auditory cortex can enhance the perception of speech syllables, particularly improving phonetic categorization abilities in individuals.

Cathodal tDCS specifically improved performance on a voice onset time continuum and was associated with increased auditory evoked potentials, suggesting a potential therapeutic approach for treating speech-related disorders linked to temporal processing deficits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Changed categorical perception of consonant-vowel syllables induced by transcranial direct current stimulation (tDCS). Heimrath, K., Fischer, A., Heinze, HJ., et al.[2018]

References

1. Netherlands pubmed.ncbi.nlm.nih.gov

Noninvasive neurostimulation of left ventral motor cortex enhances sensorimotor adaptation in speech production. [2021]

2. Switzerland pubmed.ncbi.nlm.nih.gov

Inhibitory non-invasive brain stimulation to homologous language regions as an adjunct to speech and language therapy in post-stroke aphasia: a meta-analysis. [2022]

3. United States pubmed.ncbi.nlm.nih.gov

Comparative efficacy of non-invasive brain stimulation for post-stroke aphasia: A network meta-analysis and meta-regression of moderators. [2022]

4. United States pubmed.ncbi.nlm.nih.gov

Add-on Effects of Repetitive Transcranial Magnetic Stimulation on Subacute Aphasia Therapy: Enhanced Improvement of Functional Communication and Basic Linguistic Skills. A Randomized Controlled Study. [2022]

5. United States pubmed.ncbi.nlm.nih.gov

Neuromodulation: A combined-therapy protocol for speech rehabilitation in a child with cerebral palsy. [2022]

6. England pubmed.ncbi.nlm.nih.gov

Dataset of Speech Production in intracranial.Electroencephalography. [2022]

7. United States pubmed.ncbi.nlm.nih.gov

A microcomputer-based wearable biofeedback device to improve transfer of treatment in parkinsonian dysarthria. [2019]

8. United States pubmed.ncbi.nlm.nih.gov

The Potential Effect of Forbrain as an Altered Auditory Feedback Device. [2019]

9. Netherlands pubmed.ncbi.nlm.nih.gov

Methodology for intraoperatively eliciting motor evoked potentials in the vocal muscles by electrical stimulation of the corticobulbar tract. [2022]

10. Netherlands pubmed.ncbi.nlm.nih.gov

Noninvasive neurostimulation of left temporal lobe disrupts rapid talker adaptation in speech processing. [2023]

11. Switzerland pubmed.ncbi.nlm.nih.gov

Modulation of Speech Motor Learning with Transcranial Direct Current Stimulation of the Inferior Parietal Lobe. [2020]

12. England pubmed.ncbi.nlm.nih.gov

Differential contributions of the two cerebral hemispheres to temporal and spectral speech feedback control. [2021]

13. England pubmed.ncbi.nlm.nih.gov

Changed categorical perception of consonant-vowel syllables induced by transcranial direct current stimulation (tDCS). [2018]