How Polyvagal Theory Explains the Brain’s Stress Response
Ever been told to “just relax”… and wanted to throw a shoe?
We’ve all been there, heart racing, thoughts scattered, someone cheerfully telling us to “breathe” or “calm down,” as if we hadn’t thought of it already. If only it were that simple. The truth is, when we’re overwhelmed, our nervous system has taken the wheel. It’s not that we’re doing it wrong, it’s that our body is doing exactly what it was designed to do: protect us. Polyvagal Theory (or PVT for short) gives us a way to make sense of those moments when we freeze, snap, or go completely, and understand that finding our way to calm is often a physical path, not a mental one.
The “Big Dog” Moment
Imagine you’re walking home after work, music on, mind drifting toward dinner. Suddenly a big dog bursts out of a yard, barking like it’s trying to win an award. Your body doesn’t pause to think. Your heart rockets, your legs move, and your brain drops anything non-essential. If someone called out “What’s 2 + 2?” as you sprint past, you wouldn’t answer. And if they gave you a friendly wave, you wouldn’t wave back. Those parts of the brain are simply unavailable in that moment.
Most of us aren’t dodging dogs daily, but we are dealing with emotional “big dogs”:
a sharp tone from a boss
a painful memory
sensory overload at the shops
a familiar look on someone’s face
Your nervous system can’t always tell the difference between real threat and emotional threat. It redirects energy toward survival, and thinking clearly or connecting socially becomes harder.
The Three Survival Modes (No Judgement, Just Biology)
Our nervous system is kind of like a car that shifts gears automatically:
Ventral Vagal, The Safe & Social Gear
This is our steady mode where we can think, connect, and respond. Problem-solving and social wiring are online.
Sympathetic, The Fight or Flight Gear
This is the sprinting-from-the-dog mode. The body prepares to act, and higher thinking and social cues take a temporary back seat.
Dorsal Vagal, The Shutdown Gear
When things feel overwhelming or inescapable, the system powers down. Energy drops, thinking dulls, and connection feels far away.
These gears aren’t faults. They’re ancient survival tools. The aim isn’t to stay in one forever, but to recognise when we’ve shifted gears and learn how to support ourselves back toward steadiness when we can.
Why Thinking Straight Is Impossible in Survival Mode
When our nervous system hits the panic button, our thinking brain (the prefrontal cortex) basically goes on lunch break. That’s why in a heated moment, we can’t find the right words, we might forget what we meant to say, or later think, “Why did I react like that?” We didn’t choose it, our brain simply rerouted energy from thinking to surviving. Once our body feels safe again, the “office” reopens, and suddenly we’re back to making sense.
We’re not actually overreacting, in reality, it’s our body overprotecting.
What “Safety” Really Means (and Why Logic Can’t Fake It)
You can’t logic your way into safety. You can tell yourself, “I’m fine” a hundred times, but if your body disagrees, you’ll stay in survival mode.
Safety is a physical experience, not just a thought. Your nervous system decides based on tiny cues, a gentle tone, steady lighting, a warm voice, the rhythm of your own breathing. That’s why you can feel calm around one person and tense around another, even when both are “nice.” Your body’s internal smoke alarm (what Porges calls neuroception) is constantly scanning for cues of danger or safety, whether you notice it or not. Sometimes that alarm gets oversensitive, especially after trauma, chronic stress, or sensory overload. Like a smoke detector that goes off for burnt toast.
So How Do We Calm the Alarm?
We can learn to calm our nervous system to feel safer, without needing a yoga retreat, crystal collection, or expensive gadgets It’s not about “fixing” something, just working with our biology.
Breathe Like You Mean It
Slow, steady breathing lowers your heart rate. Breathe out for longer than you breath in. Breathe in for a count of 4, exhale for 6 (or whatever feels easy). Longer exhales activate the “rest and digest” system.
Notice Your “Glimmers”
Tiny moments of safety, a cup of tea, the sun on your skin, your pet snoring nearby, your favourite playlist, are like mini anchors. The more you notice them, the more your nervous system learns: “This is what safe feels like.”
Move Gently
Stress gets stored in the body. Walk, stretch, sway, hum, dance like nobody’s watching, anything rhythmic helps our body “shake off” tension and reset.
Co-Regulate (a.k.a. Borrow Calm)
Being around calm, kind people can help your nervous system settle. Even a text, a phone call, or listening to a familiar voice can be enough. Safety is contagious, in the best way.
A Friendly Reminder (From Your Nervous System)
That wired, frozen, or foggy feeling? That’s your body trying to keep you alive. It’s just a little overenthusiastic sometimes. With practice, you can learn to spot when you’ve shifted gears, and gently help yourself come back, no shame, no self-blame, no “shoulds.”
How It Works
Whether we’re neurodivergent, trauma-affected, stressed out, or just human, our nervous system shapes how we connect, think, and feel. Understanding Polyvagal Theory gives us permission to stop asking, “What’s wrong with me?” and start asking, “What’s my body trying to tell me?”
Resetting the Past
Your nervous system isn’t the enemy; it’s an ancient friend that just gets jumpy sometimes. The trick isn’t to control it, but to listen, soothe, and reassure it until it remembers: “Things are different now.”
