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

Inclusion Criteria: * 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 Exclusion Criteria: * 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 * Participants with unstable or non controlled neuropsychiatric illness * Participants having implanted brain medical devices * Participants with implanted pacemakers * Participants having any electrically,magnetically or mechanically activated implant * Participants having cardiac, neural or medication implants * Participants having vascular clips or any other electrically sensitive support system in the brain * Participants with serious brain injury * Participants showing damage of skin at sites of stimulation (the device can only be used in healthy skin without wounds, otherwise the resistance to current can be altered) * Participants suffering from skin problems, such as dermatitis, psoriasis or eczema * Participants suffering from severe or frequent headaches * Participants with any serious life-threatening disease such as congestive heart failure, pulmonary obstructive chronic disease, or active neoplasia * Pregnant women * Participants may not consume alcohol or controlled substances within 24 hours of the scheduled appointment Participants will complete an additional screener upon enrollment to assess medical history and current drug/medication use that may conflict with the study.