Transcranial Magnetic Stimulation for Speech Perception

Overseen By Hannah Olson, MA

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Connecticut

Must not be taking: Antidepressants, Antipsychotics, Antivirals, others

Disqualifiers: Seizure, Metal in skull, Pregnancy, others

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

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 1

Duration: 3 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how different brain areas aid in understanding speech through transcranial magnetic stimulation (TMS), which temporarily disrupts brain activity. Participants will receive TMS on various head locations and then perform tasks involving speech sound identification. The researchers aim to determine how left and right brain areas influence speech perception and learning. Right-handed individuals who are native English speakers with no history of neurological issues or speech disorders may find this trial suitable. As an unphased trial, it offers a unique opportunity to contribute to groundbreaking research on brain function and speech perception.

Will I have to stop taking my current medications?

You may need to stop taking certain medications, especially if they lower the seizure threshold, like some antidepressants, antipsychotics, and antihistamines. It's best to discuss your current medications with the trial team to see if they are allowed.

What prior data suggests that transcranial magnetic stimulation is safe for speech perception studies?

Research has shown that Transcranial Magnetic Stimulation (TMS) is generally safe. Many studies have found that participants tolerate TMS well, with most experiencing no serious problems. Specifically, these studies reported no serious side effects, suggesting TMS is a safe option for many.

Additionally, the FDA has approved TMS for certain medical uses, indicating it has passed thorough safety checks for those specific conditions. While this does not guarantee safety for every possible use, it provides reassurance about its overall safety.

In summary, TMS is considered safe and tolerable for many, with strong research supporting its safety. For those considering joining a TMS trial, these findings offer a solid basis for its use in research settings. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about using Transcranial Magnetic Stimulation (TMS) for speech perception because it offers a non-invasive method to explore and potentially enhance brain functions related to language processing. Unlike traditional speech therapy or pharmacological treatments, TMS directly targets specific brain areas involved in phonetic processing and speech perception. This technique can temporarily disrupt or alter brain activity, allowing researchers to understand the precise brain regions responsible for speech perception and how they can be modulated. By pinpointing these areas, TMS could pave the way for new therapies that more precisely improve speech-related challenges, especially in conditions where traditional treatments fall short.

What evidence suggests that transcranial magnetic stimulation is effective for speech perception?

Research has shown that transcranial magnetic stimulation (TMS) can aid stroke patients with aphasia, a language disorder, in regaining language skills. TMS uses magnetic fields to activate nerve cells in the brain and has improved word-finding abilities in these patients. Studies have also found TMS useful for learning how the brain processes speech. This trial will explore TMS's role in understanding speech perception by testing its effects on phonetic precision, phonetic ambiguity, and talker-specific phonetic learning. Although TMS has shown promise in these areas, researchers continue to study its broader role in understanding speech perception. ^{6 7 8 9 10}

Are You a Good Fit for This Trial?

This trial is for monolingual native English speakers with no neurological impairments, speech or language disorders, and mild or better hearing. Participants must be right-handed as confirmed by a handedness inventory.

Inclusion Criteria

I have no history of neurological diseases.

Monolingual native speaker of English

Free of speech and language disorders (per self-report, and confirmed by short language battery described by Fidler, Vance, & Plante, 2011)

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Baseline Assessment

Participants undergo structural MRI and a speech localizer using functional MRI to identify speech-sensitive voxels in the left and right temporal cortex

1 week

1 visit (in-person)

Treatment

Participants receive TMS to disrupt neural activity in the left and right temporal cortex and perform speech perception tasks

3 weeks

Multiple sessions (in-person)

Follow-up

Participants are monitored for any adverse effects and the effectiveness of the TMS intervention

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Transcranial Magnetic Stimulation

Trial Overview The study uses Transcranial Magnetic Stimulation (TMS) on different brain areas to understand their role in speech perception. It aims to create 'virtual lesions' to see how temporary disruption affects the ability to perceive speech.

How Is the Trial Designed?

Group I: Experiment 6: Disruption of talker-specific phonetic learning using TMS. Experimental Treatment 1 Intervention

Experiment 6 is designed to test whether disruption of activity in left or right temporal regions (vs. vertex control) using TMS interferes with talker-specific learning. Participants will receive stimulation at all three sites (left temporal, right temporal, vertex, with order of stimulation counterbalanced across participants). The study uses a training paradigm where one talker's speech is manipulated to always have relatively short voice onset times (VOTs) for voiceless stops (e.g., /k/ in "coal") and another to have relatively long VOTs. Immediately after stimulation, listeners will undergo a training trial where they identify sounds as mapping to Talker 1 or Talker 2's voice, and to the word (e.g. "gain" vs. "cane"). At test, listeners hear two VOT variants and are asked which is more typical of that talker's speech. The dependent variable is the accuracy of reporting which variant is typical of the talker.

Group II: Experiment 3. Phonetic ambiguity in continuous speech Experimental Treatment 1 Intervention

Experiment 3 is designed to test whether left vs. right temporal lobe stimulation selectively disrupts processing of naturally-occurring phonetic ambiguity as compared to vertex stimulation (control). Participants will receive stimulation at all three sites (left temporal, right temporal, vertex, with order of stimulation counterbalanced across participants). Stimuli will be nonsense sentences produced clearly or in a casual register. By-sentence phonetic ambiguity is estimated by the proximity of each token to other vowels belonging to different categories. Sentences will be embedded in speech-shaped noise to increase difficulty. Participants will listen to each sentence, then respond whether a visually-presented probe word appeared in the sentence ("BRASS?"). Dependent variables are accuracy and reaction time on this probe verification task.

Group III: Experiment 2. Phonetic precision disrupted by TMS Experimental Treatment 1 Intervention

Experiment 2 tests the influence of temporary disruption of activity within the left or right temporal cortex on the speed and precision of phonetic decisions compared to vertex stimulation. Participants will receive stimulation at all three sites (left temporal, right temporal, vertex, with order of stimulation counterbalanced across participants). Immediately following stimulation pulses, participants will perform a visual analog scale (VAS) phonetic rating task on tokens from the four continua, embedded in speech-shaped noise. To control for the possibility that TMS leads to a generalized deficit in categorization, a control task will involve categorization of visual objects on a morphed "dog" to "cat" object continuum. (We expect this task to be unaffected by TMS). The variables of interest are the steepness of the categorization curve, mean reaction time to all items on the continuum, and the difference in reaction time for boundary vs. endpoint tokens.

Transcranial Magnetic Stimulation is already approved in United States, Canada, European Union for the following indications:

Approved in United States as Transcranial Magnetic Stimulation for:

• Major Depressive Disorder
• Obsessive Compulsive Disorder

Approved in Canada as Transcranial Magnetic Stimulation for:

• Major Depressive Disorder

Approved in European Union as Transcranial Magnetic Stimulation for:

• Major Depressive Disorder

Who Is Running the Clinical Trial?

University of Connecticut

Lead Sponsor

Trials

194

Recruited

162,000+

National Institute on Deafness and Other Communication Disorders (NIDCD)

Collaborator

Trials

377

Recruited

190,000+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11932577/

Semantic and Phonological Abilities Inform Efficacy ... A growing body of evidence has shown that repetitive transcranial magnetic stimulation (rTMS) can enhance word-retrieval abilities in chronic aphasia.

2. sciencedirect.com sciencedirect.com/science/article/abs/pii/S0165032725009395

Phonetic evaluation of the antidepressant effects ... This study aimed to explore the relationships between voice indices and depressive symptoms, cognitive function, and sleep conditions

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8767406/

The Effectiveness of Transcranial Magnetic Stimulation (TMS ... Transcranial magnetic stimulation has shown exploratory potential to induce language recovery in aphasia poststroke [1]. Before 2014, only a few ...

4. frontiersin.org frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2013.00446/full

Utility of TMS to understand the neurobiology of speech TMS is an innovative tool to investigate processing of speech perception and imitation. TMS studies have provided strong evidence that the sensory system is ...

5. direct.mit.edu direct.mit.edu/jocn/article/36/10/2184/123681/Assessing-the-Impact-of-Transcranial-Magnetic

Assessing the Impact of Transcranial Magnetic Stimulation ... The objective of this study was to determine if sublexical SPiN performance can be enhanced by applying TMS to three regions involved in ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9094636/

Safety and recommendations for TMS use in healthy subjects ... Safety and recommendations for TMS use in healthy subjects and patient populations, with updates on training, ethical and regulatory issues: Expert Guidelines

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12384709/

Efficacy of Transcranial Magnetic Stimulation and ... Both rTMS and tDCS are generally safe and may result in meaningful improvements in language abilities [75,77]. However, findings in PPA remain ...

8. sciencedirect.com sciencedirect.com/science/article/pii/S1388245724000221

rTMS of the auditory association cortex improves speech ... Repetitive transcranial magnetic stimulation (rTMS) promotes cortical network plasticity and may enhance language comprehension in SHL patients.

9. clinicaltrials.gov clinicaltrials.gov/study/NCT00564096

Transcranial Magnetic Stimulation (TMS) in Schizophrenia Generally, the TMS treatment was reported to be well tolerated. No serious adverse effects were reported by any of the patients. There is no evidence that rTMS ...

10. sciencedirect.com sciencedirect.com/science/article/pii/S0149763419303835

Effects of online repetitive transcranial magnetic stimulation ... The final dataset included 126 studies published between 1998 and 2016, with 244 total effects for reaction times, and 202 for accuracy. Meta-analytically, rTMS ...