Clinical trial NCT03335722: Investigating Non-invasive Brain Stimulation to Enhance Fluency in People Who Stutter
Official title: Investigating Non-invasive Brain Stimulation to Enhance Fluency in People Who Stutter
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Stuttering, Developmental
Keywords: stammering
speech motor disorder
electrical current stimulation
metronome-timed speech
Lead sponsor: University of Oxford
Sponsor class: OTHER
First posted: 2017-11-08
Enrollment: 43
Sex: MALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Double-blind, placebo-controlled (sham tDCS), randomised trial, with 20 participants with developmental stuttering recruited for each of the two arms of the trial.
Primary purpose: TREATMENT

Brief summary: This study aims to test whether the application of transcranial direct current stimulation (tDCS) concurrent with fluency training results in improvements in speech fluency in adults with developmental stuttering, measured up to three months after the intervention.

Detailed description: Developmental stuttering affects 5% of children and persists to adulthood in about 1%. Changing the way speech is produced in adults who stutter is a particular challenge for speech and language therapy and there is a need for novel interventions. One such intervention involves the application of transcranial direct current stimulation (tDCS) alongside therapies aimed at improving speech fluency. tDCS influences brain activity by modulating neuronal plasticity through the application of weak electrical currents across the brain. Pairing tDCS with speech therapy has potential for producing larger or longer lasting effects and reducing time spent in therapy.

The study will evaluate the potential of tDCS combined with speech fluency training to improve outcomes in people who stutter (PWS). PWS will have this training while receiving tDCS for five days (1 milliampere \[mA\] for 20 mins per day) in a double-blind randomized controlled trial. Outcomes will be measured in terms of changes to stuttering severity.

An additional research questions is how changes in interactions between sensory and motor brain regions relate to changes in speech fluency in PWS. MRI will be used to measure brain structure and function and the vocal tract during speech production. Transcranial magnetic stimulation (TMS) will assess motor excitability before and after the training.

Eligibility criteria: Inclusion Criteria:

* Participant is willing and able to give informed consent for participation in the study.
* Diagnosed with developmental stuttering of mild-moderate or greater severity
* Native speaker of English
* Normal or corrected-to-normal vision
* Normal hearing

Exclusion Criteria:

* Speech, language or communication disorder other than developmental stuttering.
* Contraindication to brain stimulation (tDCS or TMS)
* Contraindication to MRI
* History of drug abuse
* History of a neurological or psychiatric illness
* Any previous neurosurgical procedures
* Taking prescription or over-the-counter medication that may affect brain function (for example, anti-depressants)
* Family history of epilepsy (first degree relative)
* Severe claustrophobia (as they may be unable to tolerate scanner)

Primary outcomes:
measure: Change in Stuttering Severity Instrument (SSI-4) Score
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
Secondary outcomes:
measure: Change in percentage of disfluent syllables produced during conversation
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
measure: Change in percentage of disfluent syllables produced during reading
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
measure: Change in Overall Assessment of the Speaker's Experience of Stuttering (OASES) score
timeFrame: 6 weeks and 12 weeks after the end of the 5-day intervention
Other outcomes:
measure: Change in Premonitory Awareness in Stuttering Scale
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
measure: Change in Beck Anxiety Inventory
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
measure: Change in Subjective rating of stuttering severity
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
measure: Change in Subjective rating of speech naturalness
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
measure: Change in Objective rating of stuttering severity
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
measure: Change in Objective rating of speech naturalness
timeFrame: 1 week, 6 weeks and 12 weeks after the end of the 5-day intervention
Locations:
city: Oxford
country: United Kingdom
facility: Department of Experimental Psychology, University of Oxford
Study officials:
affiliation: University of Oxford
name: Kate E Watkins, PhD
role: PRINCIPAL_INVESTIGATOR
References: