The Effect of the Non-invasive Brain Stimulation on the Speech Fluency Enhancement

The Effect of the Combined Treatment Approach of Delayed Auditory Feedback and Transcranial Direct Current Stimulation to Enhancement of Speech Fluency in Adults Who Stutter

The aim of this study is to determine the effectiveness of concurrent transcranial direct current stimulation (tDCS) and fluency training in adults with developmental stuttering. We examine the severity of stuttering to investigate the effect of treatnment. In the control group the anodal tDCS and DAF will applied on six consecutive days (1 milliampere [mA] for 20 mins per day), and the control group will received the sham stimulation and DAF for the same time. The severity of stuttering measured by means of tasks and questionnaires before and after treatment sessions and 6 weeks after intervention.

Inclusion Criteria:

• History of developmental stuttering
• Participants diagnosed with moderate to severe stuttering
• Right handed
• Native speaker of Farsi

Exclusion Criteria:

• Speech or language disorders other than stuttering
• Received stuttering treatment within the past year
• Hearing loss
• History of neurological or psychiatric disorders
• History of seizure
• Taking any medication that may affect brain function such as anti-depressants