A scientist argues the yoga community should stop treating polyvagal theory as established science. Heart-rate variability isn't solely controlled by the vagus nerve, the freeze response hasn't replicated, and the theory's three-state model oversimplifies how the nervous system actually works. The language can still help with self-awareness, but presenting it as fact damages credibility.
Next, I have one that is going to be potentially unpleasant. I think no one likes to have their way of thinking challenged, but I think it's really important to go through some things. And so, all right, let's talk about polyvagal theory. So I think it's time to, for the yoga community to move on from polyvagal theory. And I'm gonna provide my argument. So first, polyvagal theory, just to summarize it for anyone who's not familiar, is this way of thinking about the vagus nerve and how it relates to our social function and how we're able to adapt to the world. And it was developed by this researcher, Stephen Porges, and it basically posits that The autonomic nervous system is this ancient system that over time has been repurposed as we have evolved. And some of these old functions we're kind of stuck with, and this can result in like trauma responses and stuff like that. So, okay, like on a very high level, that seems like, oh sure, that makes sense. And I think actually a lot of people in the yoga community find a lot of benefit in this. They relate to that idea. It matches what they've experienced potentially with their students or themselves, and they find that talking about it helps people, which I totally respect. I also think it's amazing that for people who maybe weren't interested in neuroscience or the brain before, polyvagal theory is a way into thinking about the brain and maybe ultimately self-regulating themselves in some ways because they're like, oh, what I'm feeling right now is just a response of my brain. Totally for that. However, I don't think the full theory is necessary for any of that. I think you can think about your brain and your vagus nerve totally separate from polyvagal theory. And ultimately, I hope to show you that polyvagal theory is wrong. It's not considered an established or respected theory in the field. So first, there's no evidence that the autonomic nervous system was repurposed for social function, which is one of the main tenets of polyvagal theory. So social function and trauma, they depend on way more than the autonomic nervous system. So So it's not like if you like transplanted someone's vagus nerve, you could fix their trauma. So it's not just a problem in the vagus nerve. It is a problem with many systems in the brain, many circuits in the brain. And yes, the vagus nerve is part of it, but it is not the crux of it. Second, the main evidence used for polyvagal theory is insufficient. So one of the main pieces of evidence is that there are changes in heart rate variability. But we should all know that heart rate variability doesn't only depend on the vagus nerve. So even if the vagus nerve is part of heart rate variability, there are other responses that control it, including the sympathetic nervous system, including just our breathing, and including something called the baroreflex. So all of that together is what's changing heart rate variability. So if we base the entire argument on heart rate variability, we're not basing it only on the vagus nerve. Next, this whole like dorsal ventral vagal complex thing, it's failed to be replicated multiple times that that is what mediates freeze behavior. Yeah. So that's another core tenet that is just scientifically wrong. And then another thing is the autonomic nervous system doesn't exist in these 3 states. So it's not like socially functioning, rested, fight or flight, or freeze. There are way more states possible. And this is because the autonomic nervous system functions on kind of independent dials. So the sympathetic can go up a little bit. The parasympathetic could also go up a little bit with it. It could go down. So it's a very finely tuned system. It's not 3 states. And so essentially polyvagal theory is a, an oversimplification and not scientifically accurate. And I think personally that it hurts our credibility scientifically to reference it as a scientific fact. So yes, the vagus nerve is relevant for yoga, but that doesn't mean the vagus nerve is everything or that polyvagal theory is everything. And I don't think we need polyvagal theory to explain yoga. So I still think that some people find it really useful for thinking about their psychophysiologic state to say, I'm kind of in a freeze response. I'm kind of in a fight or flight. It really helps with noticing and modulating how they're feeling. So useful for metacognition and self-regulation. But I think we could just refer to it as a metaphor instead of calling it scientific fact. And I think that that would be way more appropriate.
