Vagus Nerve Understanding for Moms

Anna Santini
Feb 23
8 min read

If you were in an emergency situation, would you fly into action, or freeze up? Different people respond differently, and it is all based on their personal temperament and conditioning of their nervous system. Brene Brown talks about how during family crises, she tends to "over-function", by frantically doing everything. One of her sisters, on the other hand, tends to "under-function", seemingly incapable of doing anything.

This example is can show up with everyday stress as well. .

We feel overwhelmed by our messy house, so we avoid cleaning.

We snap at our kid before thinking.

We're afraid we'll be late, so we rush around, spilling our coffee in the process.

"Stress made me do it."

There's a lot of truth to that. Understanding the way stress works can teach you so much about yourself and others. Understanding how to influence your stress response can change your life.

How Your Nervous System Works

You’ve probably heard of the “fight or flight” response - your body’s instinctive reaction to danger. Going into fight or flight is often called “activation” of the nervous system. Here’s how it works.

Your central nervous system makes up the brain and spinal cord, and processes information. Your peripheral nervous system branches out from there carrying signals to and from the body. It contains the Autonomic Nervous System [ANS], “autonomic” referring to processes that occur automatically, without conscious control. The ANS regulates involuntary functions like heart rate, digestion, breathing, body temperature, and stress responses. Every thought, emotion, and feeling is processed and influenced by the nervous system. Here is a beautiful short video illustration of the all-encompassing nature of our nervous system.

Nervous System: the complex network of nerve cells that transmit signals between different parts of the body to maintain life.
The nervous system = Stay Alive System.

The ANS (Remember - A for automatic!) can be broadly divided into two branches:

Sympathetic: Activates the stress response (fight or flight) when it perceives a threat. A perceived threat may be anything in your environment (like an ambulance siren), or in your head (like "what if my boss fires me?").
Parasympathetic: Activates Relaxation (rest and digest). Counter balance to the stress response. “Para” as in parachute, slows everything down.

Both sympathetic (stress) and parasympathetic (rest) responses are essential. We can’t survive without being able to detect and respond to threats, and we can’t stay alive without periods of recovery and restoration.

The problem arises when the sympathetic system stays active for too long. Stress hormones are catabolic, meaning they burn energy and break down tissues, while relaxation hormones are anabolic, helping rebuild and restore the body.

Adrenaline: the instant acute stress hormone
Cortisol: the ongoing chronic stress hormone.

💡Biological systems are always seeking balance.

Regularly shifting back into a parasympathetic state helps maintain homeostasis - the body’s state of balance and stability.

When we can’t return to a state of safety “rest and digest”, suffering follows: physical pain, psychological distress, health problems, and relationship dramas.

Nervous System Resilience is the Goal

We want our nervous systems to be resilient in two main ways:

Everyday: to respond and go up and down in activation based on the daily demands of our lives.
Long term: to adapt adapt and keep functioning across weeks, months, and years.

The goal is for the nervous system to stay flexible, so we can respond appropriately to stressors rather than being rigidly stuck in high alert or shut down.

Challenges, changes, and stressors will always arise. We want to be able to roll with the punches, recover swiftly, and get back up again.

And big picture, we want to avoid the health complications known to be associated with damaging long term stuck stress.

💡Chronic stress is linked to:

Heart disease
Digestive disorders
Immune dysfunction
Depression and anxiety
Sleep disorders
Hormonal disruption
Cognitive decline and memory impairment

The Vagus Nerve: Communication Highway between Brain and Body

A key player in this system is the vagus nerve, which is the longest cranial nerve and a major part of the parasympathetic branch of the ANS running from the brainstem through your neck, heart, lungs, and gut. “Vagus” means wander in latin. It acts like a bidirectional communication highway carrying signals both from the brain to the body and from the body back to the brain, with 80% of the signals going from the body up to the brain.

Polyvagal Theory is the name for the study of the vagus nerve and how it works. The word “vagus” means wandering, and “poly” means “many,” which makes sense because the vagus nerve has multiple branches.

Plus, it’s not just a single nerve, it’s actually a pair, with one on each side of the body.

The nervous system is made up of both ancient, more primitive pathways and a newer, mammalian one.

Evolutionarily, these states emerged in a certain order, and they continue to work in that order.

“As we are challenged in our daily life, we move backwards on the timeline of evolution.” ~Deb Dana, Polyvagal researcher, clinician, author, teacher

The main thing to remember:

💡 The vagus nerve registers safety, and returns us to it.

The vagus nerve acts like a brake on the stress response, signaling the body to shift back into a calm, parasympathetic state when it senses safety.

“The vagus nerve is the pathway to safety. When it’s activated, it tells the body: ‘You’re safe enough to connect, to rest, to heal.’” ~ Stephen Porges, Neuroscientist, Researcher/Developer of Polyvagal Theory, Author, Father

Ventral Vagal: “Tend & Befriend”

The ventral vagal branch of the parasympathetic nervous system is the most evolved part of our autonomic regulation. Emerging with mammals, it gives us powerful instincts of social connection, bonding, and caregiving. Ventral Vagal is the nervous system state of parenting.

The balance between sympathetic and parasympathetic states isn’t a simple on-off switch. It’s a continuum. We fluidly shift between states depending on what’s happening around and within us.

Sympathetic doesn’t always equal full on fight or flight. There is a range of responses between alert … excited … panicked, and everything in between. For example, low-level sympathetic activation when paired with positive social cues like connection and support creates a healthy, energized, and productive state. This is known as the social engagement system.

Imagine of the kind of excitement you feel when enjoying a party or working on a meaningful project.

Increasing activation could build into fight (which may look like not necessarily fighting with your partner, but being a bit snippy, or even having hostile thoughts in your head) and/or flight (which may look like not necessarily actually running away, but escaping into your phone).

At the same time, the parasympathetic system isn’t just about rest. It also drives “tend and befriend” behaviors, which is our biological instinct to seek safety through connection.

Neuroception: The Nervous System’s Built-In Safety Detector

Neuroception is the nervous system’s automatic detection sensor for safety, danger, or threat that is always scanning beneath the level conscious awareness.

A key factor in this process is social cues. As social beings, our nervous systems evolved to rely on connection for survival. For early humans (and all mammals) separation from the group meant certain death. This deep wiring is why we are deeply wired to seek belonging and why connection is a primary pathway to feeling safe.

Research has even identified a fourth “F” in the stress response called “fawn”. Fawn is like a submissive dog rolling over to the bigger more dominant dog, communicating “don’t hurt me! Don’t hurt me! Don’t hurt me!”

Fawn shows up as people-pleasing, approval-seeking, rejection sensitivity, and fear of abandonment. It’s a favorite of my nervous system, how about yours? These behaviors don’t come from weakness; they are deeply ingrained survival instincts.

💡 Connection with others is needed to detect safety.

Journalling to Learn the Language of the Nervous System

⚠️ Note: Avoid re-activating yourself with trauma memories. Those PTSD fears and memories are best looked at with a trained therapist of some kind. If you have a trauma history, for these self guided exercises, please stick to "mild" and "unease" versus the capital T trauma fears.

Print this or draw a similar grid in your journal. If you need more space, or want to free form journal, that works too!
The bottom row represents a relaxed or calm energized state. The nervous system activation increases on the way up, so the middle row is "fight or flight", and the top row is "freeze. While the nervous system is a fluid spectrum and there are many overlapping states, these are the Big 3 buckets.
Working through this grid will help you connect the learning about the nervous system to your own real life memories and sensations.
Instructions to follow below.

Get Started:

Starting at the lower left hand corner marked with a ‘1’, take notes in each box, working your way up through the layers of nervous system activation.

💡It may be helpful to close your eyes, take a deep breath letting your body relax, and search inside for memories, feelings, and associations.

Memories

BOX 1: Write down a memory of a time you can remember feeling safe & connected.

BOX 2: Write down a memory of a time you can remember feeling a survival response of Fight/ Flight/ Fawn.

BOX 3: Write down a memory of a time you can remember feeling a survival response of Freeze.

💡Tip: If you can't remember a time when you personally were in a state, write a memory about a character or scene from a movie.

Clues

List ways your system indicates it’s in a survival response. Write down any sensations and associations that come to you. Look through your memories for clues.

BOX 4: What does the parasympathetic ventral vagal safety state “tend and befriend” feel like, emotionally and in my body?

Physical: I.e. Relaxed, open, happy, etc.
Mental: I.e. Calm, confident, capable, etc.
Emotional: I.e. Safety, belonging, connection, peace, etc.

BOX 5: What Clues can I identify that I am experiencing a survival response Fight/ Flight/ Fawn?

Physical: I.e. tightness in the torso, shallow or rapid breathing, sweaty palms, racing heart, tunnel vision, etc.
Mental: I.e. talking fast or defensively, not being able to remember words or communicate clearly, fogginess, repetitive obsessive thoughts. Look for clues that your prefrontal cortex may be partially hijacked by amygdala fear hormones)
Emotional: I.e. anxiety, urge to cry, anger, resentment etc.

BOX 6: What does the dorsal vagal “freeze” state of feeling activated in a survival response feel like?

Physical: I.e. numb, coursing energy & frozen at the same time, stuck, paralyzed, slow, etc.
Mental: I.e. shut down, distant, dissociated, etc.
Emotional: I.e. confusion, overwhelm, depressed, etc.

State

In your own words, find a Name for each of these 3 states. Choose a combination of words that is easy to remember, makes sense to you, and go together.

BOX 7: Parasympathetic Ventral Vagal BOX 8: Sympathetic. BOX 9: Dorsal Vagal

Here are some examples you can take, or use these to get you started with your own ideas:

Safety Fight/Flight Freeze
Green Light / Yellow Light/ Red Light
Sun/ Storm/ Fog
Safety/ Survival / Shutdown
I can… / I Have to… / I just can’t…
Love / Stress/ Nothing
Acceptance/ Anxiety/ Apathy

Have fun with the exploration, try to do it in the spirit of curiosity, as an impartial observer of yourself, the way you would examine something you find in nature with a magnifying glass.

Not sure what your nervous system responses are like? Time to investigate.

As always feel free to write to me with observations or questions anna@motherflow.com.

Wishing you peace until next time,

Anna