Before Porges’ (2011) polyvagal theory became widely known, it was commonly thought that the autonomous nervous system has only two branches: the sympathetic system which manages in times of stress, ...

Co-authored by Lotus Huyen Vu and Robert T. Muller, Ph.D. In 1994, Stephen Porges introduced the polyvagal theory, based on an evolutionary, neuropsychological understanding of the vagus nerve’s role ...