For everyone asking for a link there is none because that is some AI aggregate that only posts headlines and no actual articles. The closest I can find to that is this: A study of one person at his "repetitive request" In the months following the start of stimulation, the frequency of stuttering gradually decreased by 46%, and the stuttering became significantly less severe. When we turned off the deep brain stimulation without the patient knowing the timing, the stuttering worsened again, demonstrating a genuine biological effect dependent on the strength of the brain stimulation." Unlike Parkinson's patients, whose tremors typically diminish immediately after starting brain stimulation and return as soon as the stimulation is stopped, the stuttering in this case increased very slowly after the stimulation was turned off https://www.news-medical.net/news/20251009/Deep-brain-stimulation-shows-promise-in-reducing-severe-stuttering.aspx