The Nervous System and Trauma: Why Your Body Keeps the Score

For decades, we treated trauma as a purely psychological problem—a "mind" issue. We believed that if we could just talk about the traumatic events enough, if we could just change our thoughts and logic our way through the pain, we would heal.

But if you are a trauma survivor, you already know the flaw in this approach. You can sit in a therapist's office and understand, logically, that you are perfectly safe. You can know, intellectually, that the abuse wasn't your fault. Yet, the moment someone raises their voice, or you smell a certain cologne, or a partner pulls away slightly, your heart begins to race, your stomach drops, and you are gripped by an overwhelming sense of terror or complete numbness.

Your logical brain knows the danger is in the past, but your body is reacting as if the threat is happening right now.

This is because trauma is not just a psychological event; it is a physiological injury. As Dr. Bessel van der Kolk famously coined, the body keeps the score. To truly heal from trauma, including Complex PTSD (CPTSD), we have to stop focusing solely on the mind and start understanding the nervous system.

The Autonomic Nervous System: Your Internal Surveillance System

To understand how trauma gets trapped in the body, we need to look at the Autonomic Nervous System (ANS). The ANS is your body's internal surveillance and regulation system. It runs automatically, without your conscious control, managing everything from your heart rate and digestion to your breathing and immune response [1].

The ANS has two primary branches that are meant to work together in a rhythmic dance:

1. The Sympathetic Nervous System (The Gas Pedal): This is your mobilising system. When you need energy to exercise, or when you perceive a threat, the sympathetic nervous system hits the gas. It floods your body with adrenaline and cortisol, increases your heart rate, and prepares your muscles for action. This is the famous fight-or-flight response.

2. The Parasympathetic Nervous System (The Brakes): This is your calming system. Once a threat has passed, the parasympathetic system hits the brakes. It stops the release of stress chemicals, slows your heart rate, and shifts your body into a state of "rest and digest."

In a healthy nervous system, these two branches work in harmony. You experience a stressor (like a near-miss in traffic), your sympathetic system spikes to keep you safe, and once the danger is gone, your parasympathetic system brings you back to baseline.

What Happens During Trauma?

Traumatic stress occurs when you face a life-threatening or profoundly overwhelming event and you cannot escape. Your sympathetic nervous system hits the gas pedal to the floor, initiating the fight-or-flight response, but the action is blocked. You are trapped, helpless, or overpowered.

When fight-or-flight fails, your nervous system resorts to its most primitive, last-resort defence mechanism: the freeze response (often associated with the dorsal vagal branch of the parasympathetic nervous system).

The freeze response is a state of collapse. Your body shuts down, you become numb, your heart rate drops, and you may dissociate. It is the biological equivalent of an animal playing dead to survive a predator.

In the wild, if the animal survives, it will literally shake off the excess survival energy and return to normal. But humans are different. We often don't discharge that massive buildup of survival energy. The traumatic event ends, but the nervous system remains stuck.

The Long-Term Impact: Living Outside the Window of Tolerance

When trauma is unresolved, the nervous system loses its flexibility. It forgets how to find the brakes, or it forgets how to take its foot off them.

Dr. Dan Siegel coined the term the "Window of Tolerance." This is the optimal zone of nervous system arousal where you feel calm, grounded, and able to handle the normal stresses of life [2]. When you are inside your window of tolerance, you can think clearly and connect with others.

Trauma fundamentally shrinks your window of tolerance. You become easily pushed out of this safe zone into one of two extremes:

1. Hyperarousal (Stuck on the Gas)

When your nervous system is stuck in sympathetic dominance, you are in a chronic state of hyperarousal. Your body believes danger is lurking around every corner. This looks like:

- Chronic anxiety, panic attacks, or a constant feeling of dread.

- Hypervigilance (always scanning the room, sitting facing the door).

- An exaggerated startle response (jumping out of your skin at a loud noise).

- Irritability, sudden rage, or an inability to relax or sleep.

2. Hypoarousal (Stuck on the Brakes)

When your nervous system is stuck in the dorsal vagal freeze response, you are in a chronic state of hypoarousal. Your body believes the only way to survive is to shut down completely. This looks like:

- Depression, chronic fatigue, or a feeling of physical heaviness.

- Emotional numbness or feeling "dead inside."

- Dissociation, brain fog, or feeling disconnected from reality.

- An inability to speak or take action when stressed.

It is incredibly common for trauma survivors to oscillate wildly between these two states. You might spend days feeling frantic and panicked (hyperarousal), until your system becomes so exhausted that it crashes into a numb depression (hypoarousal). It feels like driving with one foot slamming the gas and the other slamming the brake.

Why Talk Therapy Isn't Always Enough

If your nervous system is stuck in survival mode, the language centers of your brain (the prefrontal cortex) literally go offline. This is why traditional "talk therapy" often falls short for trauma survivors. You cannot talk a dysregulated nervous system out of a panic attack or a freeze response.

To heal, we have to use a "bottom-up" approach. We have to start with the body.

Somatic Healing: Rewiring the Nervous System

Healing trauma requires teaching your nervous system that the war is over. It involves expanding your window of tolerance so that you can experience the world without your body constantly preparing for disaster.

This is the focus of somatic (body-based) psychotherapies and trauma-informed modalities like EMDR. Here is what that healing process looks like:

1. Tracking the Body (Somatic Awareness)

The first step is learning to simply notice what is happening inside your body without judgment. We call this somatic awareness. Instead of analysing why you are anxious, you learn to notice where the anxiety lives in your body. Is it a tightness in your chest? A buzzing in your arms?

2. Resourcing and Regulation

Before we ever process traumatic memories, we must teach your nervous system how to find the brakes. This involves building a toolkit of grounding and regulation techniques. We might use specific breathing exercises, mindful movement, or vagus nerve stimulation (like humming or splashing cold water on your face) to manually shift your nervous system out of hyperarousal and back into your window of tolerance.

3. Pendulation

In somatic therapy, we use a technique called pendulation. This involves gently swinging your attention back and forth between a place of discomfort in your body and a place of safety or neutrality. This teaches your nervous system that distress is not permanent, and that it has the capacity to recover.

4. Processing the Stuck Energy

Once your nervous system has the capacity to stay regulated, we can use therapies like EMDR to process the stuck traumatic memories. Because you are anchored in the safety of the present moment, your brain can finally digest the frozen memory, releasing the trapped survival energy and allowing your nervous system to reset [3].

Your Body is Trying to Protect You

If you are exhausted from living in a body that feels like it is constantly betraying you, please know this: your nervous system is not broken. It is actually working exactly as it was designed to. It adapted to keep you alive in an unsafe environment.

But you don't have to live in survival mode forever. With time, patience, and the right somatic tools, you can retrain your nervous system to feel safe again.

If you are looking for trauma-informed therapy in Christchurch (Ōtautahi) or online across Aotearoa New Zealand, I am here to help. At Inward Journey Counselling, we don't just talk about the past; we work directly with your nervous system to help you build safety, process trauma, and reclaim your life. Reach out today for a free 15-minute consultation to begin your inward journey.

Trauma and Physical Health: When the Body Speaks

One of the most under-discussed aspects of trauma is its profound impact on physical health. Because the nervous system governs so many of the body's automatic functions, chronic dysregulation has real, measurable consequences for your physical wellbeing.

When your sympathetic nervous system is chronically activated, your body produces elevated levels of cortisol and adrenaline. Over time, this creates an inverse relationship with your immune system: high cortisol suppresses immune function, leaving you more vulnerable to illness and infection. When the immune system is chronically suppressed and then suddenly "unchecked," it can result in widespread inflammation, which is now understood to be a contributing factor in conditions ranging from autoimmune disorders to chronic pain and cardiovascular disease [4].

Trauma survivors are significantly more likely to experience chronic pain, digestive disorders (such as IBS), headaches, fatigue, and autoimmune conditions. This is not psychosomatic in the dismissive sense of the word — it is a genuine physiological consequence of a nervous system that has been stuck in survival mode for too long.

This is one of the most compelling reasons why trauma healing must involve the body. Talking about trauma can provide insight, but it does not necessarily discharge the survival energy that is stored in the tissues, muscles, and organs. Somatic therapies, breathwork, and mindful movement are not "extras" in trauma treatment — they are essential.

Practical Nervous System Regulation Tools

While working with a trauma-informed therapist is the most effective path to healing, there are evidence-based tools you can begin using right now to support your nervous system. These are not cures, but they are genuine physiological interventions that can help shift your nervous system out of survival mode and back toward safety.

Physiological Sigh: This is one of the fastest ways to activate the parasympathetic nervous system. Take a deep inhale through your nose, then take a second short inhale on top of it (a "double inhale"), and then release a long, slow exhale through your mouth. The extended exhale is the key — it is the exhale, not the inhale, that activates the vagus nerve and triggers the calming response.

Cold Water on the Face: Splashing cold water on your face, or holding a cold pack to your cheeks and forehead, activates the "dive reflex" — a mammalian survival response that rapidly slows the heart rate and shifts the nervous system toward parasympathetic dominance. It is a fast, accessible grounding tool for moments of acute anxiety.

Humming and Singing: The vagus nerve runs through the larynx (voice box). Humming, singing, or even gargling activates the vagal tone and sends a signal of safety to the nervous system. This is why many people find singing in a choir or humming a familiar tune to be instinctively calming.

5-4-3-2-1 Grounding: When you feel yourself being pulled out of the present moment by a trauma response, use your senses to anchor yourself. Name five things you can see, four things you can touch, three things you can hear, two things you can smell, and one thing you can taste. This technique works by redirecting your brain's attention from the internal threat response to the external, present-moment environment.

The Importance of Co-Regulation

Humans are not designed to regulate their nervous systems in isolation. We are social mammals, and our nervous systems are fundamentally wired to co-regulate with the nervous systems of safe others. This is why a calm, attuned presence can feel so profoundly soothing, and why isolation tends to make trauma symptoms worse.

Dr. Stephen Porges' Polyvagal Theory describes this beautifully. When your social nervous system (the ventral vagal branch) detects safety in another person's face, voice, and body language, it automatically begins to calm your own nervous system. This is why the therapeutic relationship itself is so healing. It is not just the techniques or the insights — it is the experience of being in the presence of a safe, regulated, attuned human being.

This also means that healing from trauma is not a solo project. It happens in a relationship. Whether that is a therapeutic relationship, a safe friendship, a loving partnership, or a community, connection is not a luxury in trauma recovery — it is a biological necessity.

If you are in Christchurch (Ōtautahi) or anywhere in Aotearoa New Zealand, and you are ready to begin working with your nervous system rather than against it, I would be honoured to walk alongside you. Trauma-informed counselling at Inward Journey Counselling offers a warm, safe, and collaborative space to begin the process of healing from the inside out. Reach out today for a free 15-minute consultation.

References

[1] Harvard Health Publishing. "Understanding the stress response." https://www.health.harvard.edu/staying-healthy/understanding-the-stress-response

[2] National Institute for the Clinical Application of Behavioral Medicine (NICABM). "How to Help Clients Tolerate Dysregulation and Return to a Window of Tolerance." https://www.nicabm.com/trauma-how-to-help-your-clients-understand-their-window-of-tolerance/

[3] Bessel van der Kolk, M.D. The Body Keeps the Score: Brain, Mind, and Body in the Healing of Trauma. Viking, 2014.