I think if you're thinking about training the brain to be wired differently, I'd think more about practicing slowing things down and breathing techniques. It's hard to work this into daily life. I remember once when I was a kid reading a book where a character talked about saying a mantra the entire time they were awake. They were trying to achieve enlightment. It sounded crazy then and it sounds nuts now. Who can do that besides maybe monks? I do think there is something there though about yoga and mediation and rewiring the brain to be more calm. Have you tried that book Power of One? Who knows? Maybe in this ritual stuttering can be more managed.