The Forest, the Trees, and the Pattern Between – A Personal Response to recent criticism of Polyvagal Theory
The leaf cannot be understood without the branch, the branch without the trunk, the trunk without the roots, nor the tree without the forest. Perhaps peace begins when we stop studying the pieces in isolation and remember the living system, they belong to.
I was inspired to write this article in response to the critique of Stephen Porges, whose work I have been following for well over a decade. I was always searching for a science that was more holistic, more unifying on a mind-body level, and Porges made me feel as though science was finally catching up with yoga and other ancient practices through Polyvagal Theory.
Not just any wandering nerve, but one that tells an evolutionary story. One that explains aspects of human experience that science has often left out of textbooks because it did not fully understand the anatomy and interconnectedness of the body. Porges also highlighted the conscious aspects of the vagus nerve—our ability to self-regulate, tune into our bodies in new ways, rewrite old narratives, and shine a light on the social engagement system. His work reminds us that, fundamentally, we need each other to regulate and thrive.
I have used his teachings alongside the work of many inspiring neuroscientists, including Norman Farb, Kathy Kerr, and David Creswell, who specialise in interoception and self-regulation. Together, they represent a wave of researchers who have finally begun bridging the gap between body and mind, rather than repeating the Cartesian model of medicine, where mind and body are often viewed as separate entities rather than parts of an integrated whole.
Paul Grossman and colleagues have devoted considerable energy to critiquing Stephen Porges’ work, but much of that criticism feels like an exercise in academic nit-picking. Rather than engaging with the Polyvagal Theory as a whole. Grossman et al focus on isolated details and measurements like Porges’ use of Heart Rate Variability (HRV) as a measure for Vagal Tone that Porges himself claimed was not the sole measure or foundation of his model. Similarly, they take issue with his comparative anatomy with our Reptilian ancestors which I will look at later in the article.
And beyond all this, they think that there is too much focus on a nerve that we cannot feel. What do they mean by “feel” – should we be feeling the vagus nerve only in terms of pain, like sciatica? For me, this is exactly the invitation of Stephen Porges’ work to become more interoceptive, to listen to bodily signals, to tune into subtlety – all as a model for feeling safe, regulated and connected.
There are many references and clarifications in Stephen Porges’ book that address many of these concerns and yet they have been overlooked. The result is a critique that creates more controversy than clarity. It is a missed opportunity—scientific progress is better served by building on valuable ideas and refining them than by dismantling them over technicalities while ignoring the broader contribution. Polyvagal Theory: Debunked? Not really—more nit-picking than neuroscience.
Science and Healing Interconnected
We need a science that can explain why things do not work, even when scans appear normal. We need frameworks that help us understand conditions such as IBS, fibromyalgia, anxiety, depression, and chronic pain—conditions that often cannot be fully addressed through a limited Cartesian outlook that sees mind and body as separate entities. It is when we move beyond this dualistic thinking and embrace a more integrated perspective that solutions begin to emerge.
Modern medicine is extraordinary when it comes to emergency care. Yet when it comes to long-term health challenges, it can sometimes function as little more than a bandage over deeper issues. We need approaches that address root causes, and the vagus nerve may be one of the key pieces of that puzzle—a wandering nerve that helps unite body and mind, allowing us to check in with ourselves, maintain balance, and become more preventative and attentive in our approach to health.
Porges was critiqued by scientist Paul Grossman, whose work, if you read it carefully, is not actually worlds apart from Porges’ own. Yet much of the critique focuses on isolated aspects of Polyvagal Theory rather than engaging with the model as a whole. For example, Porges himself cites numerous sources and openly acknowledges that measures such as HRV are not global or all-encompassing measures of vagal function.
The critique has often been described as a straw-man argument—focusing on selected elements of the theory and presenting them as the main target for criticism, while failing to acknowledge the broader framework or represent the research in its full context.
As with any theory that attempts to bridge multiple disciplines, Porges’ work has invited debate and differing interpretations. This is a healthy part of the scientific process. However, it can sometimes be difficult for new frameworks to gain acceptance when they challenge long-standing assumptions or encourage us to view familiar problems through a different lens.
At the same time, there has been a huge explosion of interest in trauma and the vagus nerve, with social media full of posts giving us ‘3 Quick Vagus Nerve Hacks’ or selling us courses on how to regulate our nervous system. Polyvagal Theory has been dumbed down and reduced to social media soundbites, so there is a need for conscious education.
More training is undoubtedly needed if we are to effectively address trauma and mental health disorders. However, the world of psychoanalysis also needs to embrace the worlds of somatics, interoception, mindfulness, and emerging neuroscience—now, not a hundred years from now.
Now is the time to build socially cooperative and caring networks across every field – including science. There is a dialogue to be had and a system that helps explain how connection, safety, and regulation work. Rather than remaining detached, flat in affect, or dissociated from one another, we should be putting that knowledge into practice.
In my workshops, I have witnessed first-hand the difference that vagus nerve practices can make. I have seen people with autism become more confident, expressive, and communicative. I have seen people struggling with chronic stress and tension discover genuine relief and a renewed sense of calm. Work that achieves meaningful results in the real world deserves thoughtful consideration and exploration, not dismissal based on fear or professional territorialism.
For that reason, I will continue to share Stephen Porges’ work wholeheartedly—and, perhaps, that is exactly what a well-toned vagus nerve would do.
“Be curious, not judgemental.” — Walt Whitman
In a world increasingly shaped by division, you would hope that scientists, of all people, would embody curiosity, humility, and a willingness to unite different perspectives. Yet science, like much of human culture, is still influenced by ego, territorial thinking, and fear. Ironically, many of the people debating compassion, co-regulation, and nervous system safety may need those principles the most.
This may sound random, but imagine asking three scientists from different medical disciplines the same question: Why did the chicken cross the road? A biomechanist might say: because muscle contraction, ATP release, and joint mechanics produced movement. An endocrinologist might say: because hormones and neurochemistry motivated the behaviour. A cardiologist would likely frame it through cardiovascular demand and physiological response.
Each answer contains truth, but…
One of the central issues within medicine and science is that every discipline develops its own categorical “bucket” for understanding reality. As Robert Sapolsky discusses in Behave, scientists often become deeply attached to the framework of their particular field. Their interpretation becomes the interpretation. The result is fragmentation rather than integration.
We live in a world of division: mind versus body, psychology versus physiology, emotion versus biology. Even within science itself there are silos that prevent collective wisdom from emerging fully.
To understand where this split originated, we need to go back to the 17th century and the work of René Descartes. Before Descartes, medicine was deeply intertwined with spirituality and religion. Disease was often interpreted through moral or mystical frameworks. Descartes proposed a separation between mind and body: the soul belonged to God, while the body belonged to nature and mechanics.
This idea transformed medicine.
The body became a machine. Muscles became levers. Nerves became wires. The heart became a pump. Because the soul was considered sacred and immaterial, it could not be dissected—but the body could. This Cartesian split laid the foundation for modern medicine.
The problem is that this dualism still lingers today.
Modern medicine excels at breaking things down into parts. If a machine is broken, we identify the faulty component and repair it. But many human conditions do not fit neatly into this model: fibromyalgia, IBS, chronic fatigue, burnout, trauma syndromes, chronic pain. Sometimes scans appear “normal” while suffering is immense. Other times pathology is visible, yet symptoms are absent.
In many cases, treatment becomes symptom suppression rather than root-cause understanding.
Bridging the Gap
This is where Stephen Porges attempts to bridge a major gap.
Polyvagal Theory proposes a more integrated, bidirectional model of human physiology—one in which the nervous system, emotional state, social connection, immune function, perception, and bodily regulation are inseparable. The vagus nerve becomes a bridge between body and mind rather than merely a passive brake pedal for the heart.
Porges challenges the implicit dualism that still dominates many scientific models.
In the 1960s, psychophysiology was heavily centred around arousal theory, sympathetic activation, and the HPA axis. Physiology was often treated as fixed, while external stressors were treated as the variables. Polyvagal Theory instead presents physiology as dynamic, relational, and adaptive.
Health, in this model, is not simply the absence of disease—it is the capacity for flexible regulation.
Regarding Grossman et al.
Paul Grossman and colleagues raise important criticisms regarding HRV measurement, phylogenetics, comparative anatomy, and the interpretation of vagal function. Some of these critiques are scientifically valuable and deserve discussion.
However, much of the disagreement appears to stem from differences in framing and measurement priorities rather than from a complete dismantling of Polyvagal Theory itself.
Excerpt One: HRV and Ventral Vagal Function
Grossman et al. argue that respiratory heart rate variability (RHRV) is only an imperfect proxy for vagal influence on the heart and that Polyvagal Theory overstates its precision.
My response is that Porges never claimed HRV or RSA were total or global measurements of vagal function. He consistently contextualised them within a larger theoretical framework and cited foundational research such as Richter and Spyer (1990) and Haselton et al. (1992).
The issue is not whether HRV measures everything. It clearly does not.
The issue is whether HRV can meaningfully reflect aspects of ventral vagal regulation within a broader integrated system. Porges argues that it can.
Polyvagal Theory also attempts to explain something that traditional autonomic models often overlook: why the vagus nerve contains pathways related not only to visceral regulation, but also to facial expression, vocalisation, breath, and social communication through special visceral efferents.
Many anatomy texts barely address this integration.
Porges’ broader point is that humans regulate one another socially. Facial expression, vocal tone, eye contact, breath, and relational safety influence physiology. When social engagement systems function well, heart rate, breath, and emotional state become more regulated—and some of this can indeed be reflected in HRV measures.
Essentially, we use one another to regulate our nervous systems.
The disagreement may therefore be less about whether vagal physiology exists, and more about how expansive its interpretation should be.
Excerpt Two: Reptiles and Social Behaviour
Grossman et al. challenge the idea that mammals uniquely evolved higher social regulation through the ventral vagal system, noting that reptiles and other vertebrates also display complex social behaviours.
This critique partly misunderstands Porges’ emphasis.
Porges is not arguing that reptiles are simple or incapable of social behaviour. Complexity exists throughout biology—even amoebae exhibit adaptive intelligence. His argument concerns the evolution of specific neural structures and pathways related to mammalian social engagement, particularly involving facial musculature, vocalisation, and brainstem organisation.
Mammals possess a more developed integration between facial expression, vocal prosody, breath, and autonomic regulation. When humans orient toward one another with warmth, tone, rhythm, and safety cues, physiology changes. Heart rate slows. Breath deepens. Defensive states reduce.
This is central to the Polyvagal framework.
Excerpt Three: “We Cannot Feel the Vagus Nerve”
Grossman et al. state that people cannot literally “feel” their vagus nerve and that patients primarily need validation that their symptoms are real.
Of course patients need validation. But I think this critique misses an important practical dimension of Porges’ work.
Polyvagal Theory encourages interoception: awareness of bodily state.
A pounding heart, shallow breath, gut tension, collapsed posture, tight shoulders, dissociation—these are not meaningless symptoms. They are physiological expressions of nervous system state. Through breathwork, mindfulness, movement, relational safety, somatic awareness, and therapeutic regulation practices, people can learn to respond differently to those signals.
The goal is not to “feel the vagus nerve” directly as an isolated structure.
The goal is to cultivate nervous system awareness and self-regulation.
In this sense, the vagus nerve functions as a bridge between conscious and unconscious processes—much like the breath has long functioned in yogic traditions and pranayama practices.
A Bigger Picture
What strikes me most is that Grossman’s work and Porges’ work are not actually worlds apart. Both are deeply interested in heart regulation, breathing, autonomic function, stress, and wellbeing. There is enormous overlap.
So why the rivalry?
Science progresses best not through intellectual tribalism, but through integration.
As Robert Schleip often suggests, real progress requires “walking between worlds.” It requires interdisciplinary thinking. It requires cooperative networks of care and curiosity—not merely defending territory.
Even Dacher Keltner emphasises that cooperation and social bonding are central to human flourishing.
Perhaps science itself needs more of the very qualities Polyvagal Theory speaks about: safety, openness, flexibility, and collaboration.
Porges may not have every answer. No scientist does. But he has created a model that attempts to reunite physiology, emotion, behaviour, social connection, and lived human experience into a single framework.
That alone is valuable.
Rather than forty scientists circling one scientist in opposition, perhaps the greater opportunity is for all sides to contribute their insights into a richer, more complete understanding of what it means to be human.