On this website, I love to revisit the major neurobollocks flourishing in the psychotherapy and self‑help worlds. I call out ideas that misuse the language of neuroscience to bolster practices that lack solid evidence. Today, let’s talk about one—arguably the biggest—lurking under the guise of science in our fields: the vagus nerve hacks and Polyvagal Theory (PVT).
This isn’t your standard “lizard‑brain” myth—it’s more insidious. Many neuroscientists barely know PVT exists, which means there’s surprisingly little mainstream scientific pushback. Let’s pause there: the more a concept spreads unopposed, the more critical our scrutiny must become.
I won’t fully debunk Polyvagal Theory today—that day is coming. But it’s worth flagging that I’ve spoken directly with neuroscientists and autonomic regulation experts. They tell me PVT takes a nerve that is important, detaches it from empirical grounding, then dresses it up in narrative storytelling. That’s never a good look for any therapy claiming scientific credibility.
So, today: I’ll lean into what feels safer and more practical—examining a narrow, specific case of vagus nerve marketing and how the literature doesn’t support it.
“Massage to activate the vagus nerve”: A case study
The vagus nerve—the body’s 10th cranial nerve—is undeniably vital. It swings from the brainstem down to organs like the heart, lungs, and gut, playing a crucial role in parasympathetic regulation and supporting interoception (how we sense our internal state). And yes—vagus nerve stimulation via electrical implants or transcutaneous devices is a real, scientifically studied approach.
But, there’s a proliferation of wellness claims—“vagus nerve massage”, “vagal toning”, “activate your inner peace”—tossed around without evidence.
Take one example from a “hormone expert and thought leader in women’s medicine.” She writes:
“Vagus nerve stimulation (or VNS) refers to any technique that stimulates the vagus nerve, including manual techniques such as massages…”
And she references three studies. On closer inspection—all three only involve electrical stimulation (implants or electrodes). None involve massage. One even promotes implanted devices. Yet the author then claims massage-based VNS improves “vagal tone” and builds stress resilience—without any citations.
That’s textbook mis‑citing: stringing together terms like “vagal tone,” “stress resilience,” and “vagus nerve stimulation” to imply support where none exists.
Science check: What’s the evidence (and what isn’t)?
1. Measuring vagal tone is complicated.
What’s often called “vagal tone” is not a direct measure of vagus nerve activity—but rather inferred from heart rate variability (HRV), especially respiratory sinus arrhythmia (RSA). That’s an index, not the tone itself. The relationship between vagal nerve activity and HRV is non‑linear and modulated by many factors—making simplistic interpretations misleading.
2. Polyvagal Theory’s anatomical claims fall short.
Critics including Neuhuber & Berthoud (2022) point out that the theory mischaracterizes neural structures—like wrongly linking the dorsal vagal complex to passive “freeze” or asserting a unique “ventral vagal complex” innervating facial muscles, which it doesn’t.
3. Evolutionary foundations crumble.
PVT claims that certain vagal circuits are uniquely mammalian—but evidence from lungfish and other vertebrates shows similar myelinated pathways in non‑mammals, undermining the “mammal-only” premise.
4. Experts question the theory’s overall validity.
Paul Grossman’s 2023 review argues that all five core premises of PVT are untenable, suggesting that the foundational hypotheses have been falsified.
So where does that leave us?
- Personal experience is valid, but once a therapy claims neuroscience backing, it must rest on robust evidence. You’ve walked that line—knowing what helped you most often had nothing to do with neuroscience yet still changed your life.
- Not all science-adjacent therapy is invalid—but we must discern narrative from evidence and hold our claims to real scrutiny.
References
Doody, J. S., Burghardt, G., & Dinets, V. (2023). The evolution of sociality and the Polyvagal Theory. arXiv preprint. https://arxiv.org/abs/2304.09238
Grossman, P. (2023). Fundamental challenges and likely refutations of the five basic premises of the polyvagal theory. Biological Psychology, 178, 108543. https://doi.org/10.1016/j.biopsycho.2023.108543
Monteiro, D. A., Taylor, E. W., da Silva, G. S. F., Leite, C. A. C., & Gargaglioni, L. H. (2018). Cardiorespiratory interactions previously identified as mammalian are present in the primitive lungfish. Science Advances, 4(4), eaaq0800. https://doi.org/10.1126/sciadv.aaq0800
Neuhuber, W., & Berthoud, H.-R. (2022). Functional anatomy of the vagus system: How does the polyvagal theory comply? Biological Psychology, 169, 108294. https://doi.org/10.1016/j.biopsycho.2022.108294
Taylor, E. W., Wang, T., & Leite, C. A. C. (2022). An overview of the phylogeny of cardiorespiratory control in vertebrates with reflections on the ‘Polyvagal Theory’. Biological Psychology, 169, 108295. https://doi.org/10.1016/j.biopsycho.2022.108295
Wikipedia contributors. (2024). Vagal tone. In Wikipedia. https://en.wikipedia.org/wiki/Vagal_tone
Wikipedia contributors. (2025). Polyvagal theory. In Wikipedia. https://en.wikipedia.org/wiki/Polyvagal_theory
Wikipedia contributors. (2025). Non-invasive vagus nerve stimulation devices. In Wikipedia. https://en.wikipedia.org/wiki/Non-invasive_vagus_nerve_stimulation_devices
