Understanding Stress Responses and Polyvagal Theory

Stress is a natural part of being human. In short bursts, it can sharpen focus and help us respond to challenges. But when stress becomes chronic or overwhelming, it can affect both mental and physical health.

In the UK, stress-related difficulties are increasingly common, contributing to anxiety disorders, burnout, trauma responses, and physical health complaints. To understand why stress can feel so powerful — and sometimes so hard to control — it helps to understand how the nervous system works.

Polyvagal Theory offers a helpful framework for understanding our stress responses and why we react the way we do.

The Body’s Built-In Survival System

Our nervous system is constantly scanning for cues of safety or danger. This happens automatically and largely outside conscious awareness.

Traditionally, people are familiar with the “fight or flight” response. However, modern neuroscience shows that our stress responses are more nuanced.

Polyvagal Theory, developed by Dr Stephen Porges, explains how the vagus nerve — a key nerve connecting the brain to the heart, lungs, and gut — plays a central role in regulating our emotional and physiological states.

According to this theory, we move between three primary states:

1. Safe and connected (ventral vagal state)

2. Fight or flight (sympathetic activation)

3. Shutdown or freeze (dorsal vagal state)

These states are adaptive. They exist to keep us alive.

The Safe and Connected State

When we feel safe, the ventral vagal system is active.

In this state:

• Heart rate is steady

• Breathing is calm

• We can think clearly

• We feel socially engaged

• Emotions are manageable

This is the state in which we learn, problem-solve, and build relationships effectively.

Therapy often aims to help individuals spend more time in this regulated state.

Fight or Flight: The Mobilised Stress Response

When the brain detects threat — whether physical danger, social rejection, or emotional overwhelm — the sympathetic nervous system activates.

This produces the familiar fight-or-flight response:

• Increased heart rate

• Rapid breathing

• Muscle tension

• Heightened alertness

• Anxiety or irritability

In the short term, this response is protective. It prepares the body to act.

However, when stress becomes chronic — such as ongoing work pressure, relationship difficulties, or unresolved trauma — the system can remain activated for extended periods.

This may contribute to:

• Generalised anxiety

• Panic attacks

• Insomnia

• Digestive problems

• Burnout

Freeze and Shutdown: When the System Overloads

If threat feels overwhelming or inescapable, the nervous system may shift into a dorsal vagal (shutdown) state.

This can feel like:

• Emotional numbness

• Fatigue

• Low motivation

• Disconnection

• Feeling “flat” or detached

This response is often misunderstood. It is not laziness or weakness — it is the nervous system attempting to conserve energy and protect itself.

Shutdown responses are common in trauma, depression, and chronic stress.

Why We React Before We Think

Polyvagal Theory emphasises that the nervous system responds before conscious thought.

This process, called neuroception, is the brain’s automatic detection of safety or danger.

For example:

• A critical comment may trigger fight-or-flight before you logically assess it.

• A stressful email may cause a racing heart before you consciously interpret its content.

• A reminder of past trauma may cause shutdown without immediate awareness of why.

Understanding this can reduce self-blame. Many stress reactions are physiological first and psychological second.

Chronic Stress in Modern Life

In modern UK life, threats are rarely physical. Instead, they are social, financial, relational, or digital.

Constant emails, social comparison, economic pressures, and high expectations can keep the nervous system in low-level activation for long periods.

Over time, this can lead to:

• Anxiety disorders

• Emotional exhaustion

• Irritability

• Reduced concentration

• Physical symptoms without clear medical cause

Without intentional regulation, the body may struggle to return to baseline.

Regulating the Nervous System

The encouraging news is that the nervous system is adaptable.

Therapeutic approaches often focus on helping individuals strengthen their ability to return to the safe and connected state. Strategies may include:

• Slow, controlled breathing

• Grounding exercises

• Gentle movement

• Social connection

• Trauma-focused therapy

• Mindfulness-based approaches

• Structured cognitive work (such as CBT)

Importantly, regulation is not about eliminating stress entirely. It is about increasing flexibility — the ability to move between states and return to safety more easily.

Why Understanding Stress Responses Matters

When people understand their nervous system, several things happen:

• Shame decreases

• Self-compassion increases

• Reactions feel less mysterious

• Regulation becomes more achievable

Rather than asking, “What is wrong with me?”, the question becomes, “What state is my nervous system in?”

This shift alone can be transformative.

A Compassionate Perspective

Stress responses are not character flaws. They are biological adaptations.

Whether someone experiences anxiety, shutdown, irritability, or emotional numbness, these responses began as attempts at protection.

With the right support, it is possible to retrain the nervous system, build resilience, and restore a greater sense of calm and connection.

If stress feels overwhelming or persistent, seeking professional support can help you understand your nervous system — and learn how to work with it rather than against it.

When we understand our stress responses, we begin to regain control — not by force, but through regulation and awareness.