This is perhaps one of the most important questions you can ask before starting SSP. Because if the theory behind it is up for debate, what does that mean for you? We’d rather give an honest and nuanced answer than a smooth reassurance. The short answer: yes, there is criticism—and that’s exactly what you’d expect from a living science.

What is the criticism about?

The polyvagal theory is popular among many clinicians and clients, but several scientists have criticized certain aspects of it. The criticism focuses primarily on specific evolutionary and anatomical assumptions in theory—for example, on how certain parts of the nervous system are thought to have developed according to the theory. Researchers such as Paul Grossman have written publications on this topic. The Polyvagal Institute and clinicians worldwide have subsequently responded to these in detail.

Important to note: this debate is about the theoretical basis, not whether people benefit from the applications. That is a fundamental difference. A model can be adjusted in certain respects while its practical value remains intact.

Two sides, one conversation

The discussion becomes clearest when you compare the two sides side by side. Broadly speaking, there are two opposing groups, and both have a valid point.

The Clinical Camp: "A Therapeutic Revolution"

For many trauma therapists and well-known experts—such as Bessel van der Kolk and Deb Dana—the polyvagal theory has become indispensable. In the Netherlands and Belgium, too, many trauma-sensitive professionals have embraced the model. Why are they so enthusiastic?

• It removes the question of guilt. The theory explains the freeze and fainting responses. Many people who have experienced something terrible feel ashamed because they did not fight or flee at the time. The theory shows that in situations of extreme danger, the nervous system takes control and opts for the dorsal posture (lying flat, conserving energy) in order to survive. That is not a failure; it is survival.
• It gives the body a voice. Concepts such as neuroception (unconsciously scanning for danger) and co-regulation (finding safety through the presence of another person) provide therapists and clients with concrete terms to describe physical stress responses.
• It explains why talking alone is often not enough. It provides a logical basis for why breathing, voice use, and eye contact do help to bring the nervous system back to a safe state.

The clinical wisdom you often hear: even if the biology might not be entirely accurate, it works in the treatment room—it helps people heal and brings them peace.

The neuroscience camp: "biological fiction"

On the other side are neurobiologists, physiologists, and critical psychologists. That criticism had been simmering for years, but reached a boiling point when psychophysiologist Paul Grossman, together with a large group of scientists, published an extensive paper in which the theory was deemed scientifically untenable. Their main points:

• Misconceptions about evolution. Porges argues that the nervous system evolved in three distinct evolutionary steps, with the social (ventral) vagus being unique to mammals. Biologists point out that reptiles and amphibians also have similar structures and exhibit social behavior; the evolutionary "ladder" may be too simplistic a representation.
• Anatomical oversimplification. The functioning of the vagus nerve is much more complex than three distinct states. Some claims about how specific brain nuclei control heart rhythm are contradicted by modern physiological research.
• Difficult to assess. Critics believe that the theory is formulated in such a way that it is virtually impossible to refute it scientifically.

Porges responded by saying that his critics interpret the theory too literally and too mechanistically, causing them to overlook the systemic and functional value of the model.

How We Handle It Ourselves

We believe it is important to take the scientific debate seriously and not pretend that nothing is wrong. When a client brought a critical article to our attention a while back—with the provocative title suggesting that the polyvagal theory was "dead"—we took another closer look at it, particularly through the counterarguments.

Our conclusion was not to throw everything out the window, but to choose our words more carefully. We therefore prefer to speak of the polyvagal framework and the safety science rather than a comprehensive, proven theory. And above all: we continue to work with the concepts that prove their value in practice.

• The autonomous states (safety, action, closure) as a practical compass
• Neuroception: the unconscious scanning for safety or danger
• Interoception: sensing your own body from within

The discussion does not change that foundation. These are useful, familiar concepts that help people understand what is happening in their bodies—and that provide a sense of stability during counseling.

That summary from one of our clients sums it up nicely. The experience of feeling calmer, sleeping better, or being less easily overwhelmed is separate from the question of whether science can already fully explain every underlying mechanism. Many effective approaches in medicine started out this way: first, they worked; then we gradually came to understand why.

What does this mean for you?

The great thing is: you don’t have to subscribe to any theory to experience SSP. You don’t have to believe in a model, take a scientific stance, or choose a side in an academic debate. You just listen, and you’ll see for yourself whether it helps you find more peace and security.

What we can promise you, though, is honesty. We’ll never pretend that SSP is a miracle cure or that everything has been proven down to the last detail. We’ll tell you what we know, what’s still being researched, and where the limits lie. We believe that transparency is more important than a nice story—precisely because the people who come to us have often already tried many things and deserve a realistic picture.