Bihemispheric Transcranial Direct Current Stimulation* on Speech Fluency (TDCS)

Biruni University

Status: Enrolling

Conditions: Stuttering, Adult

Treatments: Device: Transcranial direct current stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT06278233

2023/85-70

Details and patient eligibility

About

It will be determined whether bihemispheric stimulation (anodal to the left IFG and cathodal to the right IFG) is used with fluency-facilitating conditions for 5 consecutive days in individuals with stuttering and whether there is a difference in terms of the effects seen in speech fluency compared to the sham condition.

Full description

Developmental stuttering is a fluency disorder that can negatively affect many aspects of an individual's life. Recent transcranial direct current stimulation (tDCS) studies with individuals with stuttering show that tDCS shows promise in increasing fluency when used in combination with situations that temporarily increase fluency. In this study, it was aimed to investigate the effect of bi-hemispheric tDCS on fluency in individuals with stuttering for 5 consecutive days. The hypothesis of the study is that bi-hemispheric stimulation, which includes anodal stimulation to the left hemisphere and cathodal stimulation to the right hemisphere, will be effective on reading and speech fluency when performed for 5 consecutive days. Thirty-six adults with developmental stuttering are expected to complete this double-blind, sham-controlled study. Participants will be divided into two groups by blocked randomization and one group will receive sham stimulation for 5 consecutive days and the other group will receive bihemispheric stimulation. Participants in the tDCS group will receive 20 minutes of tDCS stimulation accompanied by metronome-timed speech during the practice sessions. Reading and speaking fluency will be assessed immediately before, immediately after, and one week after the stimulation sessions. Data will be collected using the stuttering severity assessment instrument (SSI-4) Results will be compared both within and between groups in terms of percentage of stuttered syllables, stuttering severity, and evaluation of the speaker's experience of stuttering.

Enrollment: 36 estimated patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• developmental stuttering
• age between 18 and 60 years
• right hand dominant

Exclusion criteria

• history of seizures, head trauma, hearing problems, cochlear implant, intracranial metal implantation, medications that affects the central nervous system, implanted neurostimulators, cardiac pacemakers, or medication infusion devices
• any speech and language disorder other than developmental stuttering
• neurological or psychiatric disorders, brain surgery, tumours, neurodevelopmental disorders, or attention deficit hyperactivity disorder

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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36 participants in 2 patient groups

Transcranial direct current stimulation study arm

Experimental group

Description:

For bi-hemispheric stimulation, the anode will be placed at the intersection of F7 and FC5 and the cathode will be placed at the intersection of F8 and FC6. For all stimulations, the stimulation will be increased for 15 seconds at a dosage of 1 mA (milliampere) for the entire 20 minute session duration and decreased for 15 seconds at the end of the stimulation.

Treatment:

Device: Transcranial direct current stimulation

Sham stimulation study arm

No Intervention group

Description:

In the sham condition, the same electrode placement will be used, during which the current will be increased for 15 seconds, kept at 1 mA for 15 seconds, decreased for 15 seconds and terminated, and the 20 minute session duration will be performed with 45 seconds of real stimulation accompanied by speech with a metronome.