Trial Outcomes & Findings for Non-invasive Brain Stimulation in Adults Who Stutter (NCT NCT03437512)

Last Updated: 2021-04-29

Results Overview

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.

Recruitment status

TERMINATED

Study phase

Target enrollment

29 participants

Primary outcome timeframe

Baseline, 1 week (post), 4 weeks (follow up)

Results posted on

2021-04-29

Participant Flow

Participants were required to meet a certain stuttering severity status. Four participants who were enrolled did not meet the pre-assignment criteria and were thus not assigned to an arm.

Participant milestones

Participant milestones
Measure	Active tDCS and Fluency Training Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days). Anodal tDCS: 20 minutes of 2mA anodal stimulation. Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes	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). Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes Sham tDCS: For sham stimulation, current is ramped up and back down over 30 seconds.
Randomized STARTED	12	13
Randomized COMPLETED	12	11
Randomized NOT COMPLETED	0	2
Received First tDCS Session STARTED	12	11
Received First tDCS Session COMPLETED	12	11
Received First tDCS Session NOT COMPLETED	0	0
Received Final tDCS Session STARTED	12	11
Received Final tDCS Session COMPLETED	12	11
Received Final tDCS Session NOT COMPLETED	0	0
Completed Study Follow up STARTED	12	11
Completed Study Follow up COMPLETED	10	10
Completed Study Follow up NOT COMPLETED	2	1

Reasons for withdrawal

Reasons for withdrawal
Measure	Active tDCS and Fluency Training Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days). Anodal tDCS: 20 minutes of 2mA anodal stimulation. Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes	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). Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes Sham tDCS: For sham stimulation, current is ramped up and back down over 30 seconds.
Randomized Withdrawal by Subject	0	2
Completed Study Follow up Could not complete study due to COVID-19 research pause	2	1

Baseline Characteristics

Non-invasive Brain Stimulation in Adults Who Stutter

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Active tDCS and Fluency Training n=12 Participants Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days). Anodal tDCS: 20 minutes of 2mA anodal stimulation. Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes	Sham tDCS and Fluency Training n=11 Participants 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). Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes Sham tDCS: For sham stimulation, current is ramped up and back down over 30 seconds.	Total n=23 Participants Total of all reporting groups
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Race (NIH/OMB) Asian	2 Participants n=5 Participants	1 Participants n=7 Participants	3 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	2 Participants n=5 Participants	1 Participants n=7 Participants	3 Participants n=5 Participants
Race (NIH/OMB) White	7 Participants n=5 Participants	8 Participants n=7 Participants	15 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Continuous	27.43 years STANDARD_DEVIATION 8.14 • n=5 Participants	23.31 years STANDARD_DEVIATION 2.87 • n=7 Participants	25.46 years STANDARD_DEVIATION 6.54 • n=5 Participants
Sex: Female, Male Female	2 Participants n=5 Participants	1 Participants n=7 Participants	3 Participants n=5 Participants
Sex: Female, Male Male	10 Participants n=5 Participants	10 Participants n=7 Participants	20 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	11 Participants n=5 Participants	11 Participants n=7 Participants	22 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Stuttering Severity	5.66 percent STANDARD_DEVIATION 3.23 • n=5 Participants	9.72 percent STANDARD_DEVIATION 8.88 • n=7 Participants	7.69 percent STANDARD_DEVIATION 6.06 • n=5 Participants
Overall Assessment of Speaker's Experience of Stuttering	2.48 score on a scale STANDARD_DEVIATION 0.58 • n=5 Participants	2.67 score on a scale STANDARD_DEVIATION 0.68 • n=7 Participants	2.57 score on a scale STANDARD_DEVIATION 0.64 • n=5 Participants

PRIMARY outcome

Timeframe: Baseline, 1 week (post), 4 weeks (follow up)

Population: One subject assigned to the sham condition did not want to participate in the MRI but participated in every other aspect of the study. Additionally, 2 subjects assigned to active and 1 assigned to sham did not complete follow up MRI due to pandemic research pause. The MRI data from one subject in the active arm was corrupted and therefore not analyzable and was excluded from MRI results. Therefore \[post-pre\] includes 11 active and 10 sham, whereas \[follow up-pre\] includes 9 active and 9 sham.

Outcome measures

PRIMARY outcome

Timeframe: Baseline, 1 week (post), 4 weeks (follow up)

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).

Outcome measures

Outcome measures
Measure	Active tDCS and Fluency Training n=12 Participants Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days). Anodal tDCS: 20 minutes of 2mA anodal stimulation. Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes	Sham tDCS and Fluency Training n=11 Participants 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). Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes Sham tDCS: For sham stimulation, current is ramped up and back down over 30 seconds.
Change in Percentage of Stuttered Syllables Produced During Speech Sample % Change post	-1.82 percent change in stuttered syllables Standard Deviation 2.22	1.06 percent change in stuttered syllables Standard Deviation 2.02
Change in Percentage of Stuttered Syllables Produced During Speech Sample % Change follow up	-1.03 percent change in stuttered syllables Standard Deviation 4.17	3.46 percent change in stuttered syllables Standard Deviation 5.47

SECONDARY outcome

Timeframe: Baseline, 1 week (post), 4 weeks (follow up)

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.

Outcome measures

Outcome measures
Measure	Active tDCS and Fluency Training n=12 Participants Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days). Anodal tDCS: 20 minutes of 2mA anodal stimulation. Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes	Sham tDCS and Fluency Training n=11 Participants 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). Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes Sham tDCS: For sham stimulation, current is ramped up and back down over 30 seconds.
Changes From Baseline on the Overall Assessment of Speakers Experience of Stuttering (OASES) Pre	2.48 score on a scale Standard Deviation .61	2.67 score on a scale Standard Deviation .75
Changes From Baseline on the Overall Assessment of Speakers Experience of Stuttering (OASES) Post	2.34 score on a scale Standard Deviation .55	2.56 score on a scale Standard Deviation .78
Changes From Baseline on the Overall Assessment of Speakers Experience of Stuttering (OASES) Follow up	2.35 score on a scale Standard Deviation .57	2.59 score on a scale Standard Deviation .88

OTHER_PRE_SPECIFIED outcome

Timeframe: Baseline, 1 week, 4 weeks

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.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Baseline, 1 week, 4 weeks

Investigators will compare performance on computerized tapping tasks from before and after tDCS to assess effects of tDCS.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Baseline, 1 week, 4 weeks

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.

Outcome measures

Outcome data not reported

Adverse Events

Active tDCS and Fluency Training

Serious events: 0 serious events

Other events: 12 other events

Deaths: 0 deaths

Sham tDCS and Fluency Training

Serious events: 0 serious events

Other events: 10 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Active tDCS and Fluency Training n=12 participants at risk Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days). Anodal tDCS: 20 minutes of 2mA anodal stimulation. Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes	Sham tDCS and Fluency Training n=11 participants at risk 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). Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes Sham tDCS: For sham stimulation, current is ramped up and back down over 30 seconds.
General disorders Headache	33.3% 4/12 • 6 weeks	18.2% 2/11 • 6 weeks
Musculoskeletal and connective tissue disorders Neck pain	8.3% 1/12 • 6 weeks	27.3% 3/11 • 6 weeks
Skin and subcutaneous tissue disorders Scalp pain	66.7% 8/12 • 6 weeks	72.7% 8/11 • 6 weeks
Skin and subcutaneous tissue disorders Tingling	100.0% 12/12 • 6 weeks	90.9% 10/11 • 6 weeks
Skin and subcutaneous tissue disorders Warm sensation	83.3% 10/12 • 6 weeks	72.7% 8/11 • 6 weeks
General disorders Sleepiness	75.0% 9/12 • 6 weeks	72.7% 8/11 • 6 weeks
General disorders Trouble concentrating	41.7% 5/12 • 6 weeks	45.5% 5/11 • 6 weeks
General disorders Acute mood change	8.3% 1/12 • 6 weeks	18.2% 2/11 • 6 weeks
General disorders Fatigue	50.0% 6/12 • 6 weeks	36.4% 4/11 • 6 weeks
General disorders Nervousness	8.3% 1/12 • 6 weeks	36.4% 4/11 • 6 weeks
General disorders Changes in visual sensations	0.00% 0/12 • 6 weeks	27.3% 3/11 • 6 weeks

Additional Information

Emily O. Garnett, PhD, CCC-SLP

University of Michigan

Phone: 734-232-3371

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	Active tDCS and Fluency Training n=11 Participants Participants will receive anodal tDCS at 2milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days). Anodal tDCS: 20 minutes of 2mA anodal stimulation. Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes	Sham tDCS and Fluency Training n=10 Participants 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). Fluency training: Speaking along with a metronome and/or speaking along with another person (choral speech) for 20 minutes Sham tDCS: For sham stimulation, current is ramped up and back down over 30 seconds.
Changes in Brain Activation as Assessed by fMRI Images left supplementary motor area (SMA) (post-pre)	1.39 Percent signal change Standard Deviation 0.45	0.81 Percent signal change Standard Deviation 0.47
Changes in Brain Activation as Assessed by fMRI Images left SMA (fol-pre)	1.03 Percent signal change Standard Deviation 0.49	0.9 Percent signal change Standard Deviation 0.54
Changes in Brain Activation as Assessed by fMRI Images right SMA (post-pre)	-0.45 Percent signal change Standard Deviation 0.48	0.49 Percent signal change Standard Deviation 0.52
Changes in Brain Activation as Assessed by fMRI Images right SMA (fol-pre)	0.86 Percent signal change Standard Deviation 0.54	0.09 Percent signal change Standard Deviation 0.35
Changes in Brain Activation as Assessed by fMRI Images left superior temporal gyrus (STG) (post-pre)	1.43 Percent signal change Standard Deviation 0.74	0.79 Percent signal change Standard Deviation 0.75
Changes in Brain Activation as Assessed by fMRI Images left STG (fol-pre)	0.09 Percent signal change Standard Deviation 0.53	0.57 Percent signal change Standard Deviation 0.85
Changes in Brain Activation as Assessed by fMRI Images right STG (post-pre)	-0.63 Percent signal change Standard Deviation 0.97	1.56 Percent signal change Standard Deviation 1.39
Changes in Brain Activation as Assessed by fMRI Images right STG (fol-pre)	0.3 Percent signal change Standard Deviation 1.07	0.83 Percent signal change Standard Deviation 1.17
Changes in Brain Activation as Assessed by fMRI Images left putamen (post-pre)	1.37 Percent signal change Standard Deviation 0.66	-0.31 Percent signal change Standard Deviation 0.58
Changes in Brain Activation as Assessed by fMRI Images left putamen (fol-pre)	2.42 Percent signal change Standard Deviation 0.71	-0.22 Percent signal change Standard Deviation 0.59
Changes in Brain Activation as Assessed by fMRI Images right putamen (post-pre)	-1.01 Percent signal change Standard Deviation 0.65	-0.74 Percent signal change Standard Deviation 0.67
Changes in Brain Activation as Assessed by fMRI Images right putamen (fol-pre)	0.89 Percent signal change Standard Deviation 0.69	0.06 Percent signal change Standard Deviation 0.86
Changes in Brain Activation as Assessed by fMRI Images left inferior frontal gyrus (IFG) (post-pre)	1.6 Percent signal change Standard Deviation 0.94	-0.33 Percent signal change Standard Deviation 0.97
Changes in Brain Activation as Assessed by fMRI Images left IFG (fol-pre)	0.23 Percent signal change Standard Deviation 0.96	0.14 Percent signal change Standard Deviation 0.74
Changes in Brain Activation as Assessed by fMRI Images right IFG (post-pre)	-0.48 Percent signal change Standard Deviation 0.80	0.11 Percent signal change Standard Deviation 0.65
Changes in Brain Activation as Assessed by fMRI Images right IFG (fol-pre)	-0.2 Percent signal change Standard Deviation 0.80	-0.2 Percent signal change Standard Deviation 0.80
Changes in Brain Activation as Assessed by fMRI Images left premotor cortex (PMC) (post-pre)	1.33 Percent signal change Standard Deviation 0.91	-0.15 Percent signal change Standard Deviation 1.67
Changes in Brain Activation as Assessed by fMRI Images left PMC (fol-pre)	0.68 Percent signal change Standard Deviation 0.96	0.62 Percent signal change Standard Deviation 1.11
Changes in Brain Activation as Assessed by fMRI Images right PMC (post-pre)	0.31 Percent signal change Standard Deviation 0.72	1.2 Percent signal change Standard Deviation 0.93
Changes in Brain Activation as Assessed by fMRI Images right PMC (fol-pre)	1.32 Percent signal change Standard Deviation 1.01	1.01 Percent signal change Standard Deviation 1.17