Polyvagal theory

Polyvagal theory, proposed by Stephen Porges in 1995, makes a claim about your vagus nerve. It says two distinct vagal branches evolved in mammals: a newer 'ventral-vagal' complex and an older 'dorsal' vagal pathway. The newer one supports social engagement; the older one supports shutdown or freeze responses. The theory is widely used in trauma therapy and somatic practice. But its claims about comparative neuroanatomy and evolution have been seriously challenged in peer-reviewed work (Grossman & Taylor 2007; Grossman 2023). Mainstream neuroscience does not treat it as established. One important caveat: the well-supported finding that vagal tone (HRV) and breathing affect your health does not depend on polyvagal theory. You should not conflate the two.

Last reviewed: June 22, 2026

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