Clinical trial NCT06740968: Transcranial Alternating Current Stimulation (tACS) in Stuttering
Official title: Improving Neural Oscillation and Synchrony Between Motor and Auditory Regions in Stuttering Using Personalized Transcranial Alternating Current Stimulation (tACS)
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Stuttering, Adult
Stuttering, Childhood
Stuttering, Developmental
Keywords: tACS
Magnetic resonance imaging
Electroencephalogram
Auditory perturbation
Neural oscillations
Nonword repetition
Brain stimulation
Lead sponsor: University of Michigan
Sponsor class: OTHER
First posted: 2024-12-18
Enrollment: 80
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: SINGLE_GROUP
Intervention model description: Participants will all receive the same treatments, however, visits 3 through 7 will have order of conditions (types of stimulation) randomized.
Primary purpose: BASIC_SCIENCE

Brief summary: The purpose of this study is to investigate how mild, noninvasive electrical brain stimulation affects speech relevant brain areas, which may in turn affect speech fluency and speaking-related brain activity in people that stutter. The long-term goal of this study is to test the therapeutic potential of transcranial alternating current stimulation (tACS) for the treatment of stuttering.

The study team hypothesizes that if stuttering involves impaired initiation of motor programs, delta-tuned tACS will strengthen communication between brain regions and decrease stuttering. Therefore, the study team delta-tuned sensorimotor tACS will be paired with fluency-induced speech (choral reading), which is hypothesized to decrease stuttering via improved auditory motor integration. However, if the primary impairment lies in planning of motor programs, the study team hypothesizes that theta-tuned tACS will strengthen communication between prefrontal and temporal brain regions and decrease stuttering.

Detailed description: Participants will have screening and baseline visits that include a variety of tests and procedures (i.e. standardized tests of speech, language, hearing test, music training questionnaire, working memory tests, and speech sample to characterize stuttering, magnetic resonance imaging (MRI) and electroencephalography (EEG)). Following these, participants will have 5 sessions (active and sham conditions) and then a one month follow-up phone call.

Of note, there will be an embedded pilot study to refine the experimental protocol in terms of practicality and feasibility and these participants will not be included in this registration. The only purpose of this embedded study is to refine the protocol and it does not have any health or behavioral outcomes.

Eligibility criteria: Inclusion Criteria for stutterers:

* Have normal language, hearing, and cognition
* Speak English as the primary language
* Currently stutter
* Score (per protocol) a certain value on the Stuttering Severity Instrument (SSI-4).
* Have not received any treatment for stuttering within the past year

Exclusion Criteria for stutterers:

* History of seizures
* Major medical or neurological illness (e.g., stroke, serious head trauma, brain infection, Parkinson's disease, etc.)
* History of closed head injury with loss of consciousness (e.g., concussion)
* Metal or electronic implants such as cochlear implants and pacemakers anywhere in the body
* Braids or other hair styling that prevents direct access to the scalp (if removal not possible)
* Currently pregnant

Primary outcomes:
measure: Change in Phase Synchronization
timeFrame: Baseline (pre-tACS), approximately 3 hours (post-tACS) (visits 3-7)
Secondary outcomes:
measure: Percentage of stuttered syllables produced during speech sample
timeFrame: Baseline (before tACS), approximately 3 hours (post-tACS) (visits 3-7)
Other outcomes:
measure: Percent change in perturbation response
timeFrame: Baseline (before tACS), approximately 3 hours (post-tACS) (visits 3-7)
measure: Change in accuracy of nonword repetition
timeFrame: Baseline (before tACS), approximately 3 hours (post-tACS) (visits 3-7)
measure: Change in Phase Amplitude Coupling
timeFrame: Baseline (before tACS), approximately 3 hours (post-tACS) (visits 3-7)
Locations:
city: Ann Arbor
country: United States
facility: University of Michigan
state: Michigan
Study officials:
affiliation: University of Michigan
name: Soo-Eun Chang, PhD
role: PRINCIPAL_INVESTIGATOR
References: