Polyvagal theory

Polyvagal theory, proposed by Stephen Porges in 1994, posits that distinct vagal branches — a phylogenetically newer ventral-vagal complex and an older dorsal vagal pathway — evolved in mammals to support social engagement versus shutdown/freeze responses. It is widely used in trauma therapy and somatic practice, but its comparative-neuroanatomy and evolutionary claims have been substantively challenged in peer-reviewed work (Grossman & Taylor 2007; Grossman 2023), and mainstream neuroscience does not treat it as established. The well-supported finding that vagal tone (HRV) and breathing influence health does not depend on polyvagal theory and should not be conflated with it.