The goal of this study is to find out whether a type of noninvasive brain stimulation can help reduce speech errors, such as repetitions, blocks, and prolongations, in people who stutter. This pilot study will help researchers design future treatments to see if targeting certain brain areas can improve speech fluency. The study will look at how people speak and behave during both speaking and non-speaking tasks before and after the brain stimulation.
Participants will complete an online survey about 24 hours before coming to the clinic. The clinic visit will last about 3 hours and will include three phases. All parts of the study will be audio-recorded.
1. Pre-Testing: Participants will first complete a stuttering evaluation to determine whether they are typical speakers or have a mild, moderate, or severe stutter. Then, they will do several speaking and non-speaking tasks. 2. Brain Stimulation: Participants will receive a session of targeted noninvasive brain stimulation (HD-tDCS). 3. Post-Testing: After the brain stimulation, participants will repeat the same evaluation and tasks they completed during pre-testing.
Brain stimulation description:
HD-tDCS is a non-invasive technique that requires the placement of several sensors (metal electrodes) on a special cap and saline gel on your head. Very low levels of constant electrical current are delivered to specifically targeted areas of the brain via these electrodes. You may experience a slight feeling of dizziness when starting the stimulation. This occurs in a small number of subjects. This takes only a few seconds and does not affect balance after the stimulation has been completed. Several research centers have previously investigated the use of this device on healthy subjects and have found the device to be safe with no direct effect on the person's well-being. Following stimulation, participants will have the opportunity to rinse out residual gel from hair and scalp.
Must be 22 years old or older
May be bi/multilingual but must speak English as dominant language.
Must be diagnosed or suspected of developmental stuttering disorder. Participants will be administered the Stuttering Severity Instrument 4 and categorized as typical speakers or mild, moderate, or severe stutterers.
Must be able to attend the session at the physical location within the clinic
Patients with preexisting speech/language disorders or previously diagnosed neurological disorders (including but not limited to apraxia of speech, cerebral palsy, dysarthria, tourettes, or any other neurological/motor condition) that affect speech/language (except stuttering) are excluded to minimize the interference of atypical brain activity.
Participants who have acquired or neurogenic stuttering (stuttering resulting from a brain injury) are excluded, as this study focuses exclusively on the effects of developmental stuttering.
Participants with a history of seizures
Participants with unexplained episodes of loss of consciousness, since such condition could be related with brain alterations or epilepsy