Examining Speech Production Errors in Stuttering Using High Definition Transcranial Direct Current Stimulation

What this Trial Is About

Researchers are evaluating whether a type of noninvasive brain stimulation called High Definition Transcranial Direct Current Stimulation (HD-tDCS) can reduce speech errors like repetitions, blocks, and prolongations in adults who stutter. This pilot study aims to help design future treatments by targeting specific brain areas involved in speech production and motor planning. Participants' speech and behavior will be assessed during speaking and non-speaking tasks before and after the stimulation to understand its effects on speech fluency. Participants will complete an online survey about 24 hours before a clinic visit that lasts about three hours. During the visit, they will first undergo a stuttering evaluation and complete speaking and non-speaking tasks. Then, they will receive a 20-minute session of HD-tDCS, where low electrical currents are applied through electrodes placed on a special cap targeting either the left inferior frontal gyrus (Broca's area) or the presupplementary motor area of the brain. After stimulation, participants will repeat the initial evaluations and tasks. Throughout the study, all sessions will be audio-recorded. Researchers will measure stuttering severity and how well participants perform naming and button-push tasks before and after stimulation. Safety will be monitored, including any dizziness during stimulation. Participants may rinse residual gel from their scalp after the session. Total participation involves the online survey plus the single clinic visit. The study is randomized and single-blinded, aiming to understand how targeted brain stimulation may influence speech production in people who stutter.

Using Non-invasive Brain Stimulation to Explore Potential Treatments to Reduce Speech Errors in Adults Who Stutter