So you're a science denier then? That's interesting. I'm unsure what you're trying to gain here, or what point you're trying to prove. You almost seem unjustifiably offended that I am sharing what the objective science says about stuttering and that I am providing an explanation to OP's question. Here's a reference for you to read if you'd like: [https://pmc.ncbi.nlm.nih.gov/articles/PMC5342907/#hbm23487-sec-0006](https://pmc.ncbi.nlm.nih.gov/articles/PMC5342907/#hbm23487-sec-0006) "More severe stuttering is associated with even greater reductions in rCBF to Broca's region"