099 - What is the Nervous System?
What happens when we meet the body where it is with safety, presence, and layered support?
In this episode, I’m offering a grounded, relational explanation of what the nervous system is — not just in scientific terms, but in terms you can really feel.
Tune in as we explore:
3:40 The science of the nervous system
7:10 Polyvagal theory
14:00 Regulation vs overwhelm
20:45 How the body keeps the score
22:00 Dysregulation and outdated patterns
30:00 Softening your protective mechanisms
Connect with Sarah
Episode Transcript
Sarah Tacy [00:00:06]:
Hello, welcome. I’m Sarah Tacy and this is Threshold.
Sarah Tacy [00:00:10]:
Moments, a podcast where guests and I share stories about the process of updating into truer versions of ourselves. The path is unknown and the pull feels real. Together we share our grief, laughter, love.
Sarah Tacy [00:00:26]:
And life saving tools. Join us hello and welcome to Threshold Moments. I am here this morning. It’s early in the morning. If you can hear my voice. I woke up thinking I would love to describe to my listeners what the nervous system is. I describe my work as nervous system support. And almost like when I taught yoga full time, it feels like the word doesn’t fully do it justice, as if we would think that the nervous system is simply a set of nerves that fire and wire in a particular way and that is the beginning and end of the story.
Sarah Tacy [00:01:27]:
So I’d love to say what does this have to do with thresholds? Our nervous system is the interface between how we perceive our situation and the tools that we have to go forward and the curiosity that we are open to or not open to. The tools that we have to regulate ourselves or to co regulate become massive in times that are hard. So when we hear the term nervous system, what seems like to me everywhere now, what does it actually mean? And how do we know if it’s dysregulated or regulated and if dysregulated is a good or bad thing even is the nervous system just doing its job? And when do we know when it’s time to update? In this episode, I’m offering a grounded relational reframe of what nervous system really is, not just in scientific terms, but in terms you can feel. Here’s how I see it. Your nervous system is your translator between your inner and outer world. It’s your rhythm keeper, your filter and timing mechanism. It’s how your body says yes, no, and not yet. Often before your brain has caught up.
Sarah Tacy [00:02:56]:
It holds your protective strategies and your potential. It’s where your instincts live and it’s also where old patterns hide. And in a world that is constantly telling us to override our instincts or or listen into your instincts but you can’t tell if it’s fear or instinct or in a world that’s telling us to speed up and be more productive at all costs. Learning how to be in right relationship with your nervous system is not just personal, it’s critical, it’s radical, it’s liberation work. So I’m going to start off with what is the nervous system? Scientifically, this part sometimes feels a little boring to me, but it’s quite important and if we can make it through this part, we might be able to make it to the part that I love just as much or maybe a tad more, which is its multi dimensional feeling and potential. So here we start very much on the 3D. If we zoom out and we define it simply. Your nervous system is your body’s communication network.
Sarah Tacy [00:04:13]:
It sometimes people talk about it looking like the old fashioned telephone network where you have an operator connecting something and turning something on or turning something off. Your nervous system includes your brain, your spinal cord and your peripheral nerves. So those are the nerves that move from your spinal cord all the way out to the tips of your fingers, tips of your toes, where your body picks up sensations from the outside and brings them back in to your central nervous system, up the spine, and then your reticular activating system and other filters show up to process. Is what I’m sensing safe? Is it predictable? Is it new? Do I need to consciously be aware of this or not? So yes, our central nervous system, brain and spinal cord, peripheral nervous system, that which connects everything else to the central nervous system. And within that there’s the autonomic nervous system, which is the part I focus on most in my work. It governs things like heart rate, breath, digestion, and most importantly for our conversation today, your stress response. And as you’ve probably experienced that when you’re feeling more stress, your heart rate changes, your breath changes, your digestion changes. So the two most popular branches that you hear about are the sympathetic nervous system.
Sarah Tacy [00:05:46]:
This is your gas pedal. This is what mobilizes you to fight or flee or take focused action in your parasympathetic nervous system. And this is often thought of as your break. It slows you down, it brings you into rest, digest and repair. There is a part that we’ll talk about about the healthy aspects of the dorsal vagal as well. So it is now thought with Polyvagal that this is oversimplified, that the parasympathetic system also includes the dorsal vagal response. And this is a state that is often thought to be a shutdown and freeze when things feel too overwhelming to manage. Right.
Sarah Tacy [00:06:29]:
So when we think of fight or flight or freeze, if you were to think of them on a map where fight or flight would be above healthy range and freeze below healthy range, and then to update, as I’m using the word healthy, we could say it can be quite healthy to freeze when you’re in an unhealthy situation. So we can look at the body’s intelligence and then we’d say it’s time to update a pattern when we’re freezing in scenarios that are actually healthy in this time and age of our life. So sometimes patterns get stuck from when we’re young. I will get back to that later in this episode. So what I’d love to then go in a little deeper on is what is polyphagal theory? So if you all are nervous system geeks like me or you’re into somatics, then you’ve probably heard of polyvagal. And for many of you, it’s probably quite new. Polyvagal theory was developed by Dr. Stephen Portis.
Sarah Tacy [00:07:30]:
It expands on the old binary of fight or flight versus rest and digest. And in that old theory, there’s like, fight or flight is bad and rest and digest is good. We have too much sympathetic. We need more parasympathetic. And this begins to broaden it into a more nuanced understanding, understanding of how our bodies respond to safety, danger and connection. It introduces the idea of the vagus nerve, which people are geeking out over these days. The vagus nerve is a key part of the parasympathetic nervous system. It has two distinct pathways.
Sarah Tacy [00:08:07]:
The ventral vagal, which people love. This is a state of connection. This is where you often feel open and social and creative and curious. Your heart and breath are regulated. You can engage with others, hold boundaries and feel rooted in the moment. This is where we’re more likely to experience co regulation, joy and relational presence. This is something that you can hear in people’s voice. When someone’s voice feels calming, then it has a sense of what we would call vagal tone.
Sarah Tacy [00:08:46]:
So in anatomy, ventral refers to the front side of the body, generally in dorsal, like a dorsal fin, the backside. I would teach people, if you think about like opening up a vent to have air come in that you’re opening it in front of you, if that’s helpful at all. And the dorsal fin on the back. So dorsal vagal, this is the other part of the vagus nerve. And this is has to do with a shutdown or freeze. But when you’re in a situation that feels too overwhelming or inescapable, your body may go into collapse, numbness and disconnection. And this is brilliant because if you think of there’s a story in one of Peter Levine’s book of a man who gets taken by a tiger and the tiger bites into his shoulder and the man goes limp and he actually doesn’t even feel the pain. And so the dorsal vagal can act as an anesthetic and the interesting thing, which again I will go into in the next section, is that that anesthetic, that freeze can happen to memories.
Sarah Tacy [00:09:53]:
It can also happen to part of our body. So it can be like, oh, I think my stomach is okay, I don’t feel anything. But it could be like you can put your hand on your stomach and you don’t feel the sensation of your hand on your stomach, like it becomes numb. Possibly someone who has had challenges with childbirth or loss or things that have constantly happened in that area may not have access to the sensation there. And so that freeze state can be how we respond to something where suddenly we shut down and we don’t have words and we don’t have access or all of our emotions shut down. But it can actually be a freeze response to being able to feel or sense areas of our body. So the dorsal vago super helpful. Sometimes it holds on too long.
Sarah Tacy [00:10:44]:
It’s not a flaw. It’s a brilliant protective response that says, if I can’t flee or fight, I’ll disappear. And we see this in nature too, that if an alligator grabs a hold of a gazelle, it will pretend to be dead. And the alligator doesn’t want to eat dead meat. And the alligator lets go for a second and then it can flee. So you tend to go to the dorsal vagal response when you feel like there is no way that you could flee or fight. And so this is actually more likely in females than it is in males, as males have most men have more testosterone than most of those who identify as female. And the testosterone is going to give us a greater sense that we can fight and often also the strength to go along with it.
Sarah Tacy [00:11:39]:
So it’s not unusual that women might skip the flee and fight and go right into a freeze, which has many different layers, which I might get into a different one. I feel like a whole different podcast can be talked about the layers of freeze. So between these states of sympathetic nervous system, which prepares us to act, to fight, flee, to push through, or to perform, there is mobilization energy in it. Sometimes it feels like power, sometimes it feels like panic. The polyvagal theory gives us a ladder model to help us move between these states throughout the day when they develop. And the polyvagal theory shows us that there was an evolution to this, so that the earliest evolution, as we were developing from single cell organisms, I’d have to go back and research just a little bit of like, what was the mechanism. But they, they can see in single cell organisms that when something is toxic that there is Actually an ability to mobilize away and then to move towards what they need. But in the simplest forms the dorsal vagal came first and that was just the ability to relax, to digest and then also to collapse, disconnect or freeze.
Sarah Tacy [00:13:05]:
This is also where you hear of dissociation. The next level, as we move up in our evolution, which is often thought of like the reptilian brain, is where we then have the ability to fight or flight. The sympathetic nervous system. This is our activation. This is also where we feel stress and survival energy. And then at the top, which they say has to do mostly with humans and possibly with primates, ventral vagal, I would say mammals. And then at the highest level humans is the ability to regulate and connect. So this is our social nervous system.
Sarah Tacy [00:13:49]:
This is really like the co regulation, that thing where we get together and we help each other feel better, where we work in community. So again this is where we’re going from. We’re not just emotional or overwhelmed in our state, but there is a story, there’s an evolution, there is wisdom behind it. What I love about John Chitty’s work on this, he talks about the polyvagal ladder, but also about really looking at when it’s feeling regulated versus overwhelmed. So he takes the ventral vagal, which is related to social connection, the top of the ladder. And when it feels regulated in health, when you feel like you have choice, you feel open, relational, curious. I think curiosity is one of our biggest tools for nervous system work. We feel creative, we feel connected, we can see the sacred third, we feel more compassionate, we can connect again with others.
Sarah Tacy [00:14:50]:
We’re able to listen again, listening with curiosity, speak more clearly, set clear boundaries, be in the unknown as we set those boundaries and feel grounded and present in the body. This is what we often think about when we think about being regulated or in resonance. But when that ventral vagal, if we’re thinking of it as the social nervous system is overwhelmed, we can match that with a little fight and flight or we can match it with a little freeze. Right. It’s not an all or nothing here. So people pleasing, we might have a freeze of our own desires and our own truth in order to appease others. So it brings us into hyper a little bit, but we’re still being social. It can bring us into over giving, over efforting to maintain harmony and performing as a state of connection instead of feeling.
Sarah Tacy [00:15:46]:
This is all very much survival based. Again especially, I mean I know it’s true for everybody, but I’d say especially for women, this was our Highest chance of survival ancestrally to be liked and to belong to a community. The more we give to them, the more need we are of for that community and the more they would protect us against harm, possibly against other men or people who are intruding. And so it was very important to be light. And so I like to emphasize that now because a lot of women these days give themselves a hard time about being people pleasers. But it is generational, ancestral and for reasons. And in healthy communities it could actually be healthy. We could have both of having our truth and kindness and generosity in this society.
Sarah Tacy [00:16:42]:
It can be a little bit more extractive and eisewaging. So then we move into the sympathetic mobilization, the fight or flight, the middle of the ladder. And when it’s healthy, this is what I love to empathize because everyone’s like, get away from fight or flight. When it’s healthy, we feel motivated, we feel energized, we feel action oriented. We can be assertive, we can be focused, we can be alert, we can meet challenges and follow through. We can have capacity to move and to protect self when needed. And when it’s dysregulated, which is how many people experience it. And again you could move back and forth between is this healthy ambition, as Aman Altay talks about, or is this toxic ambition? And the dysregulated form is anxiety and panic attacks and hypervigilance.
Sarah Tacy [00:17:34]:
It’s angry or defensive. It’s, you have your one perspective and you can’t hear anybody else’s. There’s no room for nuance, it’s all or nothing, it’s this or that. There’s rushing, there’s urgency. Which is why I’m giving this course in September called Opting out of Urgency. In my humble opinion, all the juice that life has to offer is when we opt out of urgency. So when we can have a time bound necessity but still find choice within it and still have agency within it. Going back to the list of overwhelmed, sympathetic, we’d have overworking and overworking as a sense of false, sense of feeling safety.
Sarah Tacy [00:18:23]:
And so in here is the truth that we feel unsafe, that we feel scattered and edgy. Things begin to come out sideways, we don’t know how to communicate it, we don’t know what we’re actually feeling or where the feelings come from. Then we move into dorsal vagal, that immobilization and freeze. When it’s healthy, it looks like deep rest. Think of like a midday nap or actually being able to relax when you get into a Bath, right. Many of us are like, wait, I have too many things to do. So deep rest and restoration. Stillness, presence, peace, spiritual connection, healthy solitude, creative retreat.
Sarah Tacy [00:19:06]:
Being able to go off on your own. And when I’ve heard Tal Darden speak of dorsal vagal rehab, I’ve also heard of, like, the way that a baby can eat right, drink from their mother’s breast, like that ability to connect and digest and be with another, be social at the same time. The ability to read and relax next to another, to watch TV and drop into one another’s arms. These states of deep collapse without losing yourself. The overwhelmed version is where we numb, shut down. Collapse, depression, dissociation. So things are happening, but it feels like we’re watching a movie of our own life. Fog, helplessness, a main tenant of trauma, physiology, withdrawal.
Sarah Tacy [00:19:59]:
And then the energy of, like, why bother? Which I know I can pendulate into. Sometimes when I’m trying so hard and I feel really misunderstood, I can fall into the why bother? Energy. And it’s helpful for me to know, like, oh, this is a protective mechanism, and it’s a tidal energy. It doesn’t have to stay so. This chart reminds us that none of these are bad. They’re all part of being human. And they only become painful when we’re stuck, when we lose the ability to move between them with flexibility. Moving on to part two of what we’ll go over today is this idea of how the body keeps the score.
Sarah Tacy [00:20:48]:
I’m like, oh, gosh. Each one of these could be its own podcast. So I’ll keep this part brief and I’ll go into this as a mini musing in a different one. But if you’ve heard the phrase a body keeps the score, that’s from Dr. Bethel van der Kolk’s book. He became a major mover in how we understand trauma. He worked with a lot of veterans with ptsd. Before, PTSD was really a thing that people took seriously, perhaps before it was even fully labeled.
Sarah Tacy [00:21:23]:
So as he was working with people, what he noticed is that trauma is when something overwhelming happens and you don’t have enough support, time, or choice to process it, and therefore your body holds onto it. It’s not always a memory you can talk about, but it shows up as a sensation, a reflex, and a protective response. You might not even remember the original event. And I would go on to add that things that happen to our ancestors through epigenetics can create reflexes to feel certain ways in the presence of certain things. We really won’t know why we’re having certain reactions that often aren’t appropriate to current time situations. And this protection mechanism keeps trying to protect you long after the threat is gone. That’s what we call a dysregulated nervous system, or what I would say, since it’s not all or nothing, perhaps a pattern that is outdated. So it’s not that it’s broken.
Sarah Tacy [00:22:29]:
It’s doing exactly what it was designed to do, is just stuck in an outdated loop. All of this work really helped to show that trauma is not just a memory, but that it’s stored in the body and our muscle tone and our posture. My God, there’s so many books on our posture and what it tells us about our sensations and our memories. It’s stuck in our immune response. So there’s a lot of study about childhood, adverse childhood experiences and how they can become predictors for health challenges as we grow older. What Peter Levine would add to that is that it’s not necessarily the event that happens. And I think this is what I was saying in his van der Koltz definition too. It’s when you feel like you don’t have enough support, time, or choice to process it.
Sarah Tacy [00:23:22]:
And so if Bessel van der Kolk helped us to see the imprint, Peter Levine helps us to feel the path forward. Peter Levine was the founder of Somatic Experiencing. He describes trauma not as the event itself, but as what happens in the body when we are overwhelmed and can’t complete a survival response. Peter Levine looked at animals in the wild and noticed something. He noticed, just as I was stating earlier, that when a gazelle escapes the predator, it doesn’t just move on. So I told you before about the freeze response and then the flee. But then once it gets to safety, it doesn’t just move on. It trembles, it shakes, it discharges the survival energy that was left over and that was mobilized during the chase, and it completes the response, and then it returns to regulation.
Sarah Tacy [00:24:21]:
As humans, we often suppress it. We override it, and then we try to talk about it. And the talking about it can remind us of the situation with, again, not discharging the energy. So we freeze at that moment of danger, and instead of allowing the charge to move through us, we suppress it. We move on mentally, but the body stays stuck in this unfinished loop. Levine would say trauma is not the event. Trauma is in the nervous system. And that’s a crucial distinction.
Sarah Tacy [00:25:01]:
It’s not the event, it’s how we process the event. Did we feel like we had choice? Did we feel like we were a part of the reason why we escaped, did we feel empowered? And if we felt disempowered, and if our only way was freeze, then we’re more likely to hold the memory in our body as being unsafe. We fall into, I call it empowerment physiology. When we feel like we found our way through and we got something from gives us that feeling of like, oh, if that happened again, I would have success getting through it. And then trauma physiology, which is the repeating of survival techniques and patterns that may not be useful or empowering now. So this is why in my work and in the resource framework, I don’t push for catharsis. We don’t need to dig for trauma, but what happens when we meet the body where it is with safety, with presence, with layered support. And from there the systems often show us what it’s ready to release.
Sarah Tacy [00:26:13]:
And sometimes we don’t need a story to go with it. Sometimes our body just needs the physical movements, the breath. And other times, images will arise. And as Levine speaks about, the images don’t always match with our reality, but as symbolic ways for the body to show us what the pain is. So like, if the pain was the worst rage and grief it could be, it might give us an image to match that which may or may not be equal to what actually happened in our lives. And then we say like, how do we move that? What sounds need to be made? What motions, what layers of support would we call into that memory? In resource, I would say again, we’re doing less of the individualized. That’s like a lot of one on one work, but more of on a daily basis. How do we build in fight releases? How do we build in flight releases? How do we work with our voice? What can we do collectively and communally? Because the body is always trying to complete the story.
Sarah Tacy [00:27:25]:
And our job is to create the conditions where it feels safe enough to do so. So here we are, we’ve made it the nervous system as a multi dimensional experience. So in my work I love to go beyond the science, not to bypass it, but to expand the map and to just like really be honest that what we understand scientifically can only be a small piece of the puzzle. And what we often see with science is that what we thought was for sure truth 20 years ago was not actually the full picture or perhaps even misunderstood. And so while I love to hold the science as isn’t that interesting, it can also be what else are we experiencing? What else are we noticing in our own bodies, in real time? So I love to say that the nervous system Isn’t just biological. I see how it affects people relationally, obviously, emotionally, energetically, even spiritually. It’s shaped by your early attachment experiences, your ancestral lineage. And so we get to tune in to your ancestors about what your body has learned about safety before you even had words.
Sarah Tacy [00:28:39]:
It’s shaped by collective trauma and systemic oppression and cultural narratives about what it means to be good or worthy. And just as importantly, it’s your doorway. It’s your capacity for joy, expression, creativity, connection and a sense of aliveness. Your nervous system is your interface with the world. It doesn’t just respond to danger. It responds to beauty and meaning, timing and truth. One of your first reflexes in life was awe. And I noticed as I tend more and more to my nervous system, which means my overall well being, it means my inner and outer environment.
Sarah Tacy [00:29:20]:
And creating conditions that that interface begins to laugh at more things, begins to become more silly, begins to feel the beauty in life more. And when I say that your body is your no BS gps, I mean that there is a part of you that knows, part of you that’s trying to communicate when you’re in alignment or out of alignment, meaning that here is your nervous system trying to keep you safe. And simultaneously there are messages. There’s what I would call your soul, what I would call intelligence and a great mystery running through you in which you have specific desires, specific dreams that want to emerge. And so there’s this interface happening in your body between protective mechanisms and the calling of what wants you. And the more we can soften the protective mechanisms and get them up to date with what is real now, the more room we can create for those dreams to come through and support systems for us to be able to step into what feels scary, to be able to listen to the whispers. And it can be confusing when somebody says your body is your no BS gps. And you are in a situation right now where you know you’re ready for expansion, you know you’re ready for that next relationship, you know you’re ready to go do that adventurous thing, but your body is holding you back.
Sarah Tacy [00:31:06]:
You feel like there’s an invisible wall between you and that. And our body can take thousands slower than our mind, right? So we move slowly in this work to come to the wisdom of our body. Because it can take hundreds to thousands of repetition to convince it that it’s safe after one traumatic situation that overwhelmed your system. The beauty is that when you go slow enough to listen and to go, oh, I have this feeling here and it needs this discharge so you stop Fighting the pattern. And then maybe you need less good repetitions because you can meet the parts, respond appropriately. And when you go slow enough, it can catapult you. Like. Like when you pull back, can’t think of his name.
Sarah Tacy [00:32:07]:
I heard this man, Darrell, talking about, like, when you pull back a bow, it seems like you’re going backwards. And the tension builds and attention builds, and then you release it and you catapult forward. And now you have all the resources you need to catapult forward. And like this really tall, decorative grass that I have outside now, just two months ago, it was cut down to the stubs. And for eight months out of the year, it seems like it’s gone and underground, it’s doing work. And the growth seems so slow at the beginning of the season. And the conditions have been created, and the conditions are created, and the conditions are created. And it was slow, and it was slow, and it was slow.
Sarah Tacy [00:32:58]:
And then it gets to move fast. Then all those things that you thought you couldn’t have as you tend to your nervous system start flooding into your life. And sometimes it feels slower than we can handle. But we do handle it. And we call on the resources, and we call in the resources, and we call on the resources, and we stay curious, and we stay curious, and we stay curious. And then we spring up like these hydrangeas that I’m seeing outside the window, like all the leaves I see on the trees. And there are seasons for everything. But I would love to say that your body is intelligent, the messages are wise, and we can check in over time.
Sarah Tacy [00:33:45]:
Is that still true? The more we slow down, the more we get to tune into. Is that still true?
Sarah Tacy [00:33:58]:
Thank you for tuning in. It’s been such a pleasure. If you’re looking for added support, I’m offering a program that’s totally free called, called 21 Days of Untapped Support. It’s pretty awesome. It’s very easy. It’s very helpful. You can find it@SarahTacey.com and if you love this episode, please subscribe. And, like, apparently it’s wildly useful, so we could just explore what happens when you scroll down to the bottom.
Sarah Tacy [00:34:29]:
Subscribe rate, maybe say a thing or two. If you’re not feeling it, don’t do it. It’s totally fine. I look forward to gathering with you again.
Sarah Tacy [00:34:37]:
Thank you so much.