Polyvagal Theory: What Holds Up, What Doesn’t and How to Use It Responsibly

Few ideas have shaped the somatic field as much as Polyvagal Theory. Words like “ventral vagal”, “neuroception” and “dorsal shutdown” are now part of everyday language in bodywork, coaching and trauma training. At the same time the theory has come under heavy scientific criticism. In early 2026 an international group of 39 researchers concluded that its core physiological claims are “untenable”.

So where does that leave practitioners who use the framework every week? This guide sorts out what the theory claims, what the critics say, where both sides actually agree and how to keep working with these ideas honestly.

What Polyvagal Theory claims

Polyvagal Theory was introduced by psychophysiologist Stephen Porges in the 1990s and has been revised several times since. In its popular form it says three things.

• Three autonomic states. A “ventral vagal” state linked to safety and social connection, a sympathetic state linked to fight or flight and a “dorsal vagal” state linked to shutdown, collapse or freeze.
• An evolutionary order. The dorsal branch is described as an ancient system shared with reptiles, while the ventral, myelinated branch is presented as a mammalian adaptation that supports social engagement.
• Neuroception. Porges’ term for the nervous system’s largely unconscious detection of safety or danger in the environment and in other people.

A further technical claim sits underneath much of the research: that respiratory sinus arrhythmia (RSA), the natural rise and fall of heart rate with each breath, is a direct index of ventral vagal activity.

What the critics say

The most detailed critique came from psychophysiologist Paul Grossman. In a 2023 review in Biological Psychology he examined five basic premises of the theory and concluded that they are “either untenable or highly implausible” (Grossman 2023). Much of his argument concerns RSA. He argues that treating RSA as a straightforward measure of vagal tone is a category mistake, because breathing rate and depth strongly change RSA on their own.

In February 2026 Grossman and 38 co-authors, among them specialists in autonomic physiology, cardiology and comparative evolution, published an expert evaluation in Clinical Neuropsychiatry (Grossman et al. 2026). Their abstract states: “All co-authors agree that major tenets of the PVT are not supported by past or current knowledge.” Their main points:

• Anatomy. Most heart rate changes in mammals are driven by the nucleus ambiguus, not by the dorsal motor nucleus. The authors reject the idea of a “dorsal vagal shutdown” as described in the theory.
• Evolution. Myelinated vagal fibers and breathing-related heart rate variability are found in many vertebrates, not only mammals. This undermines the idea of a uniquely mammalian social engagement system.
• Measurement. RSA is “inherently a peripheral measure” that is affected by breathing, sympathetic activity and age. It cannot be read as a direct window into vagal tone.

In an interview with MJA InSight+, Grossman added that “dismissing somatic therapies, or psychotherapy, is not the point”. His concern is that physiological claims presented as facts to clients and health professionals are not supported by the evidence (InSight+ 2026).

How defenders respond

Porges has replied to his critics, most fully in his 2023 paper “The vagal paradox: A polyvagal solution” (abridged version). He argues that critics misrepresent the theory, that RSA measured with appropriate methods does reflect vagal influence on the heart and that there is no broad expert consensus against the theory. He also acknowledges that the dorsal vagal contribution may involve blood pressure and gut effects “rather than heart rate slowing” and that “neural pathways are still being explored”.

Clinicians who use the framework tend to make a different argument. Writing in Psychology Today, MaryCatherine McDonald argues that the critique targets mechanisms, not the clinical tools built around them (McDonald 2026). A group of UC Davis clinicians put it this way in 2023: the approach is “scientifically questionable but useful in practice” (Giroux et al. 2023). Note that these are commentaries and opinion pieces, not new studies.

Where both sides agree

The debate is loud, but the common ground is larger than it looks.

• Felt safety matters. No one in this debate claims that safety, trust and a calm, attuned presence are unimportant in therapy or bodywork. The 2026 authors point out that these concepts are older than Polyvagal Theory and that “physiological knowledge of the autonomic nervous system has been neither central nor essential to the development of these concepts.”
• RSA is real. Heart rate does rise and fall with breathing. The disagreement is about what exactly it measures.
• The vagus nerve is important. It plays a central role in heart rate, digestion and many other functions. What is disputed is the specific three-state, evolutionary model.
• The theory has changed over time. Porges himself describes it as refined and updated.

What this means for practitioners

The honest position for 2026 is this: Polyvagal Theory is a popular clinical metaphor whose physiological foundations are seriously disputed by a large group of specialists. That does not make your work with safety, pacing and presence worthless. It does change how you should talk about it.

• Use it as a map, not as anatomy. “Some people find it helpful to think of three broad states” is accurate. “Your dorsal vagus has shut you down” is a physiological claim the evidence does not support.
• Describe what you observe. Breath, muscle tone, eye contact, voice, the client’s own words. These are real and you can work with them without any theory attached.
• Do not promise nervous system outcomes. Avoid claims like “this exercise activates your ventral vagus” in session descriptions, on your website or in ads. It overstates the evidence and can also create trouble with platform and advertising rules.
• Know the evidence for what you actually do. Slow breathing, attuned touch and supportive relationships have research behind them that does not depend on Polyvagal Theory. Our guide on the science of touch collects some of it.
• Stay curious. Science in this area is moving. Holding a model lightly is part of a trauma-informed attitude too.

What this means for clients

If a practitioner explains your reactions in polyvagal language, you can take what is useful and leave the rest. The experience of feeling safe or unsafe with someone is real. You do not need to accept a specific theory about your nerves in order to benefit from a calm, respectful session. It is fine to ask a practitioner how they understand the evidence behind their method. A good practitioner will welcome that question.

FAQ

Has Polyvagal Theory been “debunked”?

A group of 39 researchers concluded in 2026 that its core physiological claims are untenable. Porges and some clinicians disagree. “Debunked” is a strong word, but it is fair to say the physiological model is not established science.

Is co-regulation still a valid idea?

Yes, as a psychological and relational concept. People influence each other’s emotional state and sense of safety. That idea predates Polyvagal Theory and does not depend on it. We explore it in Co-Regulation: Why Safety Is the Foundation for Deep Intimacy.

Should I stop using polyvagal language?

Not necessarily. Many clients find the language helpful. Use it as a metaphor, say so openly and avoid presenting it as proven anatomy.

Sources

• Grossman P. (2023). Fundamental challenges and likely refutations of the five basic premises of the polyvagal theory. Biological Psychology, 180, 108589. PubMed
• Grossman P., Ackland G.L., Allen A.M. et al. (39 authors) (2026). Why the Polyvagal Theory is Untenable: An international expert evaluation. Clinical Neuropsychiatry, 23(1), 100–112. PMC
• Porges S.W. (2023). The vagal paradox: A polyvagal solution. Abridged reply, Polyvagal Institute
• Whitehead B. (2026). Polyvagal theory debunked in comprehensive new study. MJA InSight+. Link
• McDonald M. (2026). Polyvagal Theory Has Not Been “Debunked”. Psychology Today. Link
• Giroux C.A., Ahlers D., Miawotoe A. (2023). Polyvagal Approaches: scientifically questionable but useful in practice. Journal of Psychiatry Reform. Link