I mean, "mind-body relationship" is technically a defunct dichotomy (https://plato.stanford.edu/entries/consciousness/), but sure, what we do affects what we do. :) Stutter varies a lot, and it's a neat thing if we can find a pattern in what exacerbates it. We just shouldn't rest too confidently in that, I think - there's even variance within variance. For me, at least, the expectation of surprises helps me be better prepared for my stutter.