The Vagus Nerve: The Body's Bridge Between Mind and Emotions

There is so much talk on social media about the vagus nerve — cold plunges, humming, "vagal tone hacks." Much of it is well-intentioned, and some of it is even useful. However, in real life, the picture is often more complex and nuanced. Before reaching for a technique, I think it helps to actually understand what this nerve is, where it lives in the body, and why it plays such a central role in how we feel safe, how we connect with others, and how we experience emotion in the body rather than only in the mind.

This is a long read, so make yourself comfortable. Let's go through it together, gently and thoroughly.

What Is the Vagus Nerve, and Where Does It Live?

The word ‘vagus’ comes from Latin, meaning ‘wanderer’. The vagus nerve is the tenth cranial nerve and the longest nerve of the autonomic nervous system. It begins in the brainstem, at the base of the skull, and wanders downward through the neck, the chest, and into the abdomen.

Along the way, it sends and receives signals from:

- The throat and voice box, shaping the muscles involved in speech and swallowing

- The middle ear, helping us tune in to the frequencies of the human voice

- The heart, where it acts like a brake, slowing the heart rate down

- The lungs, influencing the rhythm and depth of breath

- The gut, where it plays a central role in digestion — this is where the phrase "gut feeling" actually comes from.

The vagus nerve plays an important role in such functions as:

* Digestion

* Heart rate, blood pressure and respiration (breathing)

* Immune system responses

* Mood

* Mucus and saliva production

* Skin and muscle sensations

* Speech

* Taste

* Urine and faecal output

What makes the vagus nerve so significant is that it carries information in both directions. Around 80% of its fibres carry information from the body back to the brain, while only about 20% carry messages from the brain to the body. This means that your brain is constantly receiving updates about what is happening inside your body, not simply sending instructions.

This is one reason emotional experience is felt so powerfully in the body — the tightness in the chest, the knot in the stomach, the lump in the throat. These are not metaphors. They are vagal signals, arriving in the brain from the body itself.

An Evolutionary Perspective: Why We Have Three Nervous System States

To understand the vagus nerve fully, it helps to look at it through an evolutionary lens — which is exactly what psychiatrist and researcher Stephen Porges did when he developed Polyvagal Theory in the 1990s.

Porges proposed that our autonomic nervous system did not evolve as a single on/off switch, but as three distinct circuits, layered on top of one another across millions of years of evolution. Each circuit is older or newer, and each one exists to answer a single ancient question: “Am I safe?”

1. Ventral Vagal — Safe and Social (the newest circuit)

This is the most recently evolved branch, found only in mammals. It supports connection, play, rest, and digestion. When we are in this state, the face is expressive, the voice carries warmth and melody, the heart rate is steady, and we feel able to be present with others and with ourselves. This is often described as the "home base"we are always, at some level, trying to return to.

2. Sympathetic — Fight or Flight (an older circuit)

Shared with reptiles, birds, and other vertebrates, this circuit mobilises the body for action. The heart speeds up, breath quickens, muscles prepare to move. This state exists to help us respond to danger, but it can also be activated by deadlines, conflict, or anything the nervous system interprets as threat, even when there is no physical danger present at all. When activated, the hypothalamus, pituitary, and adrenal glands pump cortisol and adrenaline througho

ut the body.

3. Dorsal Vagal — Shutdown and Freeze (the oldest circuit)

This is the most ancient pathway, shared even with reptiles and amphibians. When a threat feels inescapable: too big, too prolonged, too overwhelming, the body conserves energy by withdrawing. This can look like numbness, dissociation, exhaustion, or a sense of being far away from one's own life. This is not weakness. It is one of the oldest survival strategies life has ever developed.

What I want to say here is that none of these three states is a malfunction. Each one, at some point in evolutionary history, kept a living creature alive. The difficulty is not that we have these states — it is when the nervous system gets stuck in sympathetic or dorsal states long after the original danger has passed, unable to find its way back to ventral, safe connection.

The Social Engagement System: How the Vagus Nerve Reads the Room

One of the most fascinating aspects of Polyvagal Theory is  what Porges, 1998 calls the social engagement system — a network of nerves, closely tied to the vagus, that governs the muscles of the face, the middle ear, and the voice box.

This is why, a warm, melodic tone of voice can calm a nervous system faster than the actual words being said. Babies orient instinctively toward a caregiver's face and voice. We can often sense whether someone is safe or unsafe within moments of meeting them, long before we consciously analyse anything. The middle ear muscles literally adjust to filter out low-frequency threat sounds and tune in to the mid-range frequencies of the human voice

In other words, before we even think about whether someone is trustworthy, our nervous system has often already made a preliminary assessment — through facial expression, vocal tone, and posture. Porges calls this unconscious scanning process neuroception: perception without awareness. It happens beneath the level of thought, in the body, via the vagus nerve and its connected circuits.

This matters enormously in relationships, and it matters enormously in therapy. Co-regulation — one nervous system helping to settle another, through tone of voice, facial expression, and steady presence — is not a soft add-on to healing. It is often the mechanism of healing itself, and that’s what we do in therapy the majority of the time.

Physical Performance: The Vagus Nerve and the Body Under Load

The vagus nerve also plays a significant role in physical performance and recovery, largely through something called heart rate variability (HRV)— the small variation in time between each heartbeat.

A higher HRV generally reflects strong vagal tone, the nervous system's ability to shift flexibly between activation and rest. Athletes and coaches pay close attention to HRV because it reflects how well the body is recovering, how resilient the nervous system is under stress, and how efficiently someone can move between effort and recovery — physically and emotionally.

This is not only relevant to elite performance. In everyday life, a well-regulated vagal system means:

- Recovering more easily after a stressful conversation

- Sleeping and digesting more soundly

- Being able to mobilise energy when needed, and settle again afterwards, rather than staying wired or collapsed

Practices such as slow, extended exhalation, humming, singing, and cold exposure are popular because they stimulate the vagus nerve directly.  But I want to be honest with you: these are tools for toning an already-functioning system. They are not a substitute for addressing chronic activation that comes from trauma, chronic stress, or an environment that does not feel safe. The nervous system needs more than a breathing exercise if the underlying story it is holding has never been met.

Feeling Emotions in the Body: Why This Isn't "Just in Your Head"

I often meet people who say, "I know logically that I'm safe, but my body doesn't believe it." This is not a contradiction. It is precisely how the nervous system is built to work.

Because so much vagal signalling travels from body to brain, emotion is not primarily a thought that then produces a bodily sensation. It is often the opposite: a bodily state arises first, such as tightening, a dropping, a bracing, and the mind then works to interpret and narrate it. This is sometimes called interoception: our internal sense of the body's own state.

This is why:

- Anxiety is felt as a fluttering stomach or a racing heart before it is understood as "anxiety"

- Grief is felt as a heaviness in the chest or a tightness in the throat

- Safety is felt as a loosening in the shoulders, a fuller breath, a softening around the eyes

In therapy, whatever presentation the client has, we always bring it back to the body. We are attuning to what the body holds, rather than only analysing the story in words.  We are working directly with the vagus nerve and the wider autonomic nervous system. The body is not simply the container for emotion. It is often where emotion begins.

Bringing It Together

The vagus nerve is not a switch to be hacked, and it is not something to master or control. It is closer to a very old, very wise messenger, one that has been relaying information about safety and threat between your body and your brain since long before you had words for what you were feeling.

It is important to learn how the vagus nerve works to understand your own reactions- not "why am I like this," but "what did this response once protect me from? And what does my nervous system need now in order to feel safe enough to relax?" However, understanding only will not resolve trauma or chronic dysregulation.

If you recognise yourself somewhere in this, a body that reacts before your mind can explain why, a system that swings between overwhelm and shutdown, a longing to feel safe in your own skin, please know that this is not brokenness. It is the adaptation of your body and the intelligence of your nervous system doing its very best to protect you.

Sending you rays of warmth!

— Julia