Enhancing Speech Fluency With Non-invasive Brain Stimulation in Developmental Stuttering

This study aims to test whether the addition of transcranial direct current stimulation (TDCS) to speech fluency training results in improvements in speech fluency in adults with developmental stuttering. Half of the participants will receive anodal TDCS on five consecutive days, the other half will receive a sham stimulation for the same amount of time.

Study Overview

• Status: Completed
• Conditions: Speech Disorders; Stuttering; Fluency Disorders
• Intervention / Treatment: Device: Anodal TDCS; Behavioral: Fluency Training

Detailed Description

Studies using TDCS have shown improvements in motor performance, and in expressive language skills in clinical and healthy populations. The benefits of single sessions of TDCS are short-lived. However, stimulation over multiple sessions can increase and prolong learning effects that can persist for several weeks after the end of the stimulation period. We aim to target left hemisphere frontal regions involved in speech production with TDCS, and to pair this stimulation with speech fluency training.

• Study Type: Interventional
• Enrollment (Actual): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Oxford, United Kingdom, OX1 3UD
    • University of Oxford

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Native speaker of English.
• Right handed.
• Participant has moderate to severe Developmental Stuttering (Stammering)

Exclusion Criteria:

• Speech, language or communication disorder other than Developmental Stuttering.
• Sensory impairment (hearing loss or visual impairment)
• History of drug abuse.
• History of seizures
• History of a neurological or psychiatric illness.
• History of neurosurgical procedure.
• Currently taking certain prescription medications such as anti-depressants and anti-malarial medication (as these may lower the seizure threshold)

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: Anodal TDCS; Participants will receive anodal TDCS over the left inferior frontal cortex. TDCS will be delivered at 1milliampere (mA) intensity for 20 minutes during speech fluency training (5 consecutive days).	Device: Anodal TDCS; 20 minutes 1mA anodal stimulation to left inferior frontal cortex. Cathode positioned on right supra-orbital ridge.; Behavioral: Fluency Training; Speech tasks will be completed using fluency-enhancing techniques: metronome-timed speech and auditory choral speech.
Sham Comparator: Sham TDCS; Participants will receive sham TDCS over the left inferior frontal cortex. Sham stimulation will involve 30 seconds stimulation at the beginning of the 20 minutes of speech fluency training (5 consecutive days).	Behavioral: Fluency Training; Speech tasks will be completed using fluency-enhancing techniques: metronome-timed speech and auditory choral speech.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline proportion of stuttering in speech sample	Quantitative measurement of stuttering	1 week post-treatment
Change from baseline proportion of stuttering in speech sample	Quantitative measurement of stuttering	6 weeks post-treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline on the Stuttering Severity Instrument version 4 (SSI-4)	Standardised assessment of frequency and duration of stuttering and associated physical concomitants	1 week post-treatment
Change from baseline on the Stuttering Severity Instrument version 4 (SSI-4)	Standardised assessment of frequency and duration of stuttering and associated physical concomitants	6 weeks post-treatment
Change from baseline on Overall Assessment of Speaker's Experience of Stuttering (OASES)	Standardised assessment of the functional impact of stuttering on a person's life	6 weeks post-treatment

Collaborators and Investigators

• Sponsor: University of Oxford
• Investigators: Principal Investigator: Kate Watkins, PhD, University of Oxford

Publications and helpful links

Helpful Links

• Speech and Brain Research Group, University of Oxford

Study record dates

Study Major Dates

• Study Start: October 1, 2014
• Primary Completion (Actual): March 14, 2016
• Study Completion (Actual): March 14, 2016

Study Registration Dates

• First Submitted: September 30, 2014
• First Submitted That Met QC Criteria: November 6, 2014
• First Posted (Estimate): November 11, 2014

Study Record Updates

• Last Update Posted (Estimate): January 31, 2017
• Last Update Submitted That Met QC Criteria: January 30, 2017
• Last Verified: January 1, 2017

More Information

Terms related to this study

• Keywords: Brain stimulation; Stammering
• Additional Relevant MeSH Terms: Pathologic Processes; Nervous System Diseases; Neurologic Manifestations; Neurobehavioral Manifestations; Language Disorders; Communication Disorders; Disease; Stuttering; Speech Disorders
• Other Study ID Numbers: MSD-IDREC-C2-2014-013