Investigating Individual Differences in Speech Motor Skills in Neurotypical Speakers and Persons … (NCT07459803) | Clinical Trial Compass
Not Yet RecruitingNot Applicable
Investigating Individual Differences in Speech Motor Skills in Neurotypical Speakers and Persons With Disordered Speech
United States90 participantsStarted 2026-04
Plain-language summary
This study aims to understand how people use different types of feedback to control their speech. When an individual speaks, the brain relies on several systems at the same time, such as sensory systems that monitor an individuals own voice and the movements of their speech muscles, and a motor system that builds and reads out learned motor patterns. The investigators are studying how these systems work together and how they differ across individuals.
Investigators will test 90 adults between 18 and 50 years old, including people who stutter, people with dyslexia, and people with typical speech and reading development. Participants will complete several short speech tasks in which the sounds they hear or the movements of their jaw or larynx are briefly changed. These responses will be used to measure each person's speech motor skills and to estimate the settings of a computer model called "SimpleDIVA," which simulates how the brain controls speech.
Participants will also complete an MRI scan so investigators can measure the structure and connectivity of different brain regions. These measures will help investigators understand how individual differences in the brain relate to the speech motor control skills we observe. Participants will also complete sessions with noninvasive brain stimulation (transcranial current stimulation, or tCS) to examine how stimulation of specific areas of the brain affects responses during the speech tasks.
The knowledge gained from this study will help researchers understand why speech motor skills vary across people and how differences in neural function may contribute to conditions such as stuttering and dyslexia.
Who can participate
Age range
18 Years – 50 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Native speakers of American English
* Adults age 18-50
* Age-appropriate cognitive and receptive vocabulary skills
* Age-appropriate hearing
* Adults with dyslexia will have a history of dyslexia or report of ongoing reading difficulties that will be confirmed at the first screening visit
* Adults who stutter will have a history of stuttering that will be confirmed at the first screening visit
Exclusion Criteria:
* History of neurological disorder, including a history of seizures
* Major brain injury, brain surgery, or stroke
* Orthodontia or atypical oral structure (e.g., cleft palate) that interferes with speech
* Fluency disorder (except those in the persons who stutter cohort), apraxia of speech, or dysarthria
* Language or reading disorder (except those in persons with dyslexia cohort)
* Standardized score below 80 on the Kaufman Brief Intelligence Test
* Standardized score below 1 standard deviation on the NIH Toolbox Picture Vocabulary Test
* Pregnancy
* Severe claustrophobia
* Presence of magnetically or mechanically active implant, or other ferromagnetic material embedded in any part of the body
* Significant scalp lesions that would prevent transcranial direct stimulation
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.