While there is still no finite answer to what neurological anomaly causes a stutter, there have been some studies with both deep brain stimulation and non invasive magnetic brain stimulation with positive outcomes. In the non invasive study, 9/10 stutters became markedly more fluent. Is this 2 year old study anywhere near a cure? Probably not. But if there is going to be one I think it will be somewhere along those lines. The lack of science and information on stuttering well into the 21st century is pretty deflating. IMO it’s viewed as a insignificant affliction in comparison to other neurological disorders in the scientific community even though it severely impacts sufferers quality of life and mental health.