Non-invasive Brain Stimulation in Adults Who Stutter

Research studies in stuttering have shown that activity patterns in certain brain areas differ in people who stutter compared to people who do not stutter when speaking. The purpose of this study is to investigate how mild, non-invasive brain stimulation applied consecutively for five days affects speech relevant brain areas, which may in turn affect speech fluency and speaking-related brain activity in people who stutter.

Study Overview

• Status: Terminated
• Conditions: Stuttering, Developmental
• Intervention / Treatment: Device: Anodal tDCS; Behavioral: Fluency training; Device: Sham tDCS

• Study Type: Interventional
• Enrollment (Actual): 29
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48105
      • University of Michigan

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• history of persistent developmental stuttering
• stuttering severity ranging from mild to very severe, specifically Stuttering Severity Instrument (SSI) total score of 20 (mild) or higher and stuttering rates of 3% or higher
• scores within 1 standard deviation of the norm on the standardized tests for the study

Exclusion Criteria:

• received any treatment for stuttering within the past year
• other neurological conditions such as Tourette's syndrome or post-traumatic stress disorder
• taking any medications/drugs that affect brain function
• history of past or current mental illness for example, schizophrenia that may affect brain development and function
• history of serious medical or neurological illness such as epilepsy and Parkinson's disease
• history of closed head injury (e.g., concussion)
• history of reading disorders
• hearing loss
• taking any medication, prescription or non-prescription with any psychotropic effects at the time of the study
• metal or electronic implants such as cochlear implants, and pacemakers

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Active tDCS and fluency training; Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days).	Device: Anodal tDCS; 20 minutes of 2mA anodal stimulation.; Behavioral: Fluency training; Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes
Sham Comparator: Sham tDCS and fluency training; Participants will receive sham tDCS. Sham stimulation will involve 30 seconds of stimulation at the beginning of the 20 minutes of speech fluency training (5 consecutive days).	Behavioral: Fluency training; Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes; Device: Sham tDCS; For sham stimulation, current is ramped up and back down over 30 seconds.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in Brain Activation as Assessed by fMRI Images	Investigators will use the fMRI images taken from before and after tDCS to determine if the treatment intervention contributed to any changes within brain regions associated with speech production. This will be measured by Blood-Oxygen-Level-Dependent (BOLD) signal change (arbitrary units). Images from scans are preprocessed. Changes in BOLD signal are modeled for contrasts within a group for [post-pre] and [follow up-pre] (e.g., active group reading condition post visit MINUS active group reading pre visit). Results are reported for reading condition.	Baseline, 1 week (post), 4 weeks (follow up)
Change in Percentage of Stuttered Syllables Produced During Speech Sample	Investigators will calculate the percentage of stuttered syllables (out of total syllables) in a speech sample. Decreased stuttered syllables represents better outcomes (greater reduction in stuttering).	Baseline, 1 week (post), 4 weeks (follow up)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes From Baseline on the Overall Assessment of Speakers Experience of Stuttering (OASES)	The OASES is a standardized assessment of the functional impact of stuttering on a person's life. There are 4 sub-tests: general information about speech, your reactions to stuttering, communication in daily situations, quality of life. Each one has a score from 1 to 5 with regard to impact (1 least, 5 most negative impact). These are combined to give a total impact score between 1 and 5, with 5 representing the highest negative impact on person's life. The change on the total impact score will be used. Changes are shown in the table below by comparison between the measurements at the three points in time.	Baseline, 1 week (post), 4 weeks (follow up)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes From Baseline on Rhythm Judgement Task	Investigators will compare performance accuracy on a computerized rhythm judgement task from before and after tDCS to assess effects of tDCS. Improved accuracy reflects better performance.	Baseline, 1 week, 4 weeks
Changes From Baseline on Tapping Tasks	Investigators will compare performance on computerized tapping tasks from before and after tDCS to assess effects of tDCS.	Baseline, 1 week, 4 weeks
Changes From Baseline on Self-rated Measure of Speech Fluency	Investigators will compare participant scores on a self-rated measure of speech fluency (1 = NO STUTTERING; 9 = EXTREMELY SEVERE STUTTERING) from before and after tDCS to assess effects of tDCS. Lower scores indicate improvement.	Baseline, 1 week, 4 weeks

Collaborators and Investigators

• Sponsor: University of Michigan
• Investigators: Principal Investigator: Emily O Garnett, PhD, University of Michigan

Study record dates

Study Major Dates

• Study Start (Actual): June 25, 2018
• Primary Completion (Actual): April 1, 2020
• Study Completion (Actual): April 1, 2020

Study Registration Dates

• First Submitted: February 12, 2018
• First Submitted That Met QC Criteria: February 12, 2018
• First Posted (Actual): February 19, 2018

Study Record Updates

• Last Update Posted (Actual): April 29, 2021
• Last Update Submitted That Met QC Criteria: April 28, 2021
• Last Verified: April 1, 2021

More Information

Terms related to this study

• Keywords: MRI; tDCS; transcranial direct current stimulation; Speech; fluency
• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Neurobehavioral Manifestations; Language Disorders; Communication Disorders; Speech Disorders; Stuttering
• Other Study ID Numbers: HUM00134495

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes