Thirty-nine vagus nerve and evolution experts evaluated polyvagal theory in 2026 and called it untenable
An evaluation of Porges 2025 by 39 physiologists, anatomists and evolutionary biologists: heart-rate variability is not a direct vagal measure, 'dorsal vagal shutdown' is 'wholly untenable', and reptiles are social too.
Weak or heavily disputed. Treat as a question, not an answer. how we score evidence
Caveat on this rating: Many co-authors are longstanding critics of the theory, so this states an established position forcefully rather than coming from a neutral panel. It evaluates the theory's physiology and evolution, not any therapy. Porges's reply (same issue) says it attacks a proxy of the theory.
The largest joint statement on polyvagal theory so far, written as a direct commentary on Porges's 2025 review.
Who wrote it
Paul Grossman invited 39 researchers in the physiology and evolution of the vagus nerve and in vertebrate social behaviour, "many whose works have been cited" in polyvagal writing as support. By the paper's account all but one agreed; the one who declined said he was "unfamiliar with the PVT".
Significant findings
The paper takes five parts of the theory in turn.
Heart rate and breathing. Respiratory sinus arrhythmia, the theory's main measure, "is neither a direct nor very accurate index of vagal outflow from brain to heart", and correlations with cardiac vagal tone "are often particularly weak".
The two brainstem nuclei. The authors write that the theory's split between a calm "ventral" nucleus and a shutdown "dorsal" nucleus is "clearly wrong". In mammals the ventral nucleus drives most vagal slowing of the heart, including sudden large slowing. They write that emotional freezing or dissociation in humans do not typically cause "massive" or "lethal" slowing, and conclude "the notion of 'dorsal vagal shutdown' is wholly untenable".
Evolution. Fish, amphibians, reptiles, birds and mammals all include species with vagal braking of the heart, heart-control neurons in two or more brainstem sites, and fast myelinated fibres. Lung-breathing animals including reptiles show breathing-linked heart rhythm too.
Social behaviour. Reptiles, amphibians and birds "also exhibit complex social behaviors", against the theory's asocial-reptile story.
Citations. The paper argues the theory misreads several older studies it cites.
Their conclusion: the theory is "untenable, because it is not defensible based on existing neurophysiological and evolutionary evidence". The psychological parts, they add, come mainly from earlier psychology and "are neither clarified nor strengthened" by the theory.
The other direction
Porges replied in the same issue that the paper critiques "a reconstructed proxy of the theory" and never states conditions under which its predictions would fail. That reply is in this library. Many co-authors have published critiques before, so this is a strong statement of an existing position rather than a neutral panel. The paper says it does not set out alternative accounts of how the vagus nerve relates to feelings, "although such explanations do exist".
What this does not show
Heart rate variability research is real, and so are stress responses. Whether a polyvagal-informed therapy helps a given person is a separate question from whether the theory's physiology is right, and this paper does not test any therapy.
Source
Why The Polyvagal Theory Is Untenable: An international expert evaluation of the polyvagal theory and commentary upon Porges, S.W. (2025) — Grossman P, Ackland GL, Allen AM, Berntson GG, Booth LC, Burghardt GM, et al. (39 authors) (2026)
Indexed peer-reviewed journal
Read the source: https://doi.org/10.36131/cnfioritieditore20260110
DOI: 10.36131/cnfioritieditore20260110
How this was scored
- Study design
- Expert opinion or commentary
- Funding
- Mixed public and industry funding
- Published in
- Indexed peer-reviewed journal
- Sample size
- not recorded
- Preregistered
- not recorded
- Conflicts disclosed
- not recorded
- Independent of proponent
- not recorded
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published October 2, 2026.
Questions
How strong is the evidence behind this?
veisund rates this source "contested". Weak or heavily disputed. Treat as a question, not an answer. It scores 30 out of 100 on our published rubric. One caveat travels with that badge: Many co-authors are longstanding critics of the theory, so this states an established position forcefully rather than coming from a neutral panel. It evaluates the theory's physiology and evolution, not any therapy. Porges's reply (same issue) says it attacks a proxy of the theory. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Why The Polyvagal Theory Is Untenable: An international expert evaluation of the polyvagal theory and commentary upon Porges, S.W. (2025) — Grossman P, Ackland GL, Allen AM, Berntson GG, Booth LC, Burghardt GM, et al. (39 authors) (2026). Published in: Indexed peer-reviewed journal. DOI: 10.36131/cnfioritieditore20260110. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Expert opinion or commentary. Funding: Mixed public and industry funding. Independence from the proponent is not recorded. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.