Introduction to Polyvagal Theory

Have you ever wondered why you can feel calm and capable one moment, then anxious, overwhelmed, shut down, or exhausted the next?

Why does a simple email sometimes feel manageable on Monday but impossible on Wednesday? Why can one person leave us feeling safe and relaxed, while another leaves us tense and on edge without saying anything obviously threatening?

For many years, psychology focused primarily on thoughts, emotions, and behaviours. More recently, there has been growing interest in the role of the nervous system and how our bodies constantly monitor the world around us for signs of safety and danger. One of the most influential frameworks to emerge from this work is Polyvagal Theory.

Developed by neuroscientist Stephen Porges, Polyvagal Theory offers a way of understanding why we react the way we do under stress, why relationships are so important for wellbeing, and why simply telling ourselves to "calm down" often doesn't work. Whether you are living with anxiety, depression, trauma, ADHD, chronic stress, burnout, or simply trying to understand yourself better, Polyvagal Theory provides a useful lens through which to view human behaviour.

It starts with a simple idea. Your nervous system's primary job is not happiness. Its primary job is survival. Every second of every day, your nervous system is scanning your environment looking for signs of safety. It is also looking for signs of danger.

Remarkably, much of this process happens outside of conscious awareness. Before your thinking brain has had a chance to evaluate a situation, your nervous system has already begun deciding whether you are safe enough to connect, whether you need to prepare for action, or whether you need to conserve energy and protect yourself.

Polyvagal Theory refers to this unconscious scanning process as neuroception. Just as perception is what we consciously notice, neuroception is what our nervous system notices before conscious awareness. A person's tone of voice, their facial expression, the atmosphere in a room (have you ever walked into a room and immediately felt the tension?), perhaps an unexpected text message, a crowded shopping centre, a supportive hug.

The nervous system is constantly interpreting these experiences and adjusting our physiological state accordingly.

The Three States of the Nervous System

Polyvagal Theory suggests that our nervous system tends to move between three broad states.The first is a state of safety and connection. When we feel safe, our nervous system allows us to engage with the world. We can think clearly, solve problems, learn new information, connect with other people, and experience curiosity and playfulness. This is often called the ventral vagal state. When we are here, we generally feel grounded, flexible, and emotionally available. Challenges still exist, but they feel manageable.

The second state is mobilisation. When our nervous system detects danger, it prepares us for action. Our heart rate increases, our muscles tense, and our attention narrows. We might get ringing ears, blocked ears, tunnel or blurred vision. This is commonly experienced as anxiety, anger, frustration, panic, urgency, or hypervigilance. This sympathetic nervous system response evolved to help us fight threats or run from them.

The problem is that modern threats are rarely lions or bushfires. Instead, they are deadlines, financial pressure, conflict, uncertainty, rejection, social media, traffic, and difficult conversations. Our nervous system often reacts to psychological threats in much the same way it would react to physical threats.

The third state is shutdown. If the nervous system concludes that fighting or fleeing is unlikely to work, it may move into a conservation response. In this state our heart rate slows, energy decreases, and motivation drops. People often describe feeling numb, disconnected, exhausted, flat, hopeless, detached, or unable to think clearly. This is often referred to as the dorsal vagal state.

Many people mistakenly interpret this state as laziness, weakness, or lack of motivation. In reality, it is often the nervous system attempting to protect us by conserving energy.

The Nervous System Is Not Rational

One of the most helpful aspects of Polyvagal Theory is that it reminds us that our nervous system is not always logical. A person may know they are safe while simultaneously feeling unsafe. Someone with social anxiety may understand that a group of colleagues is friendly but still experience a racing heart and overwhelming dread. A trauma survivor may know they are no longer in danger yet still react strongly to reminders of past experiences. A person with ADHD may feel paralysed by a simple task despite genuinely wanting to complete it.

The nervous system responds to what it predicts, remembers, and perceives - not simply what is objectively true. This helps explain why insight alone does not always create change. Understanding a problem is valuable, but our nervous systems often require experience, repetition, and safety before they begin responding differently.

Why Relationships Matter So Much

One of the most powerful contributions of Polyvagal Theory is the idea that humans regulate one another. We are not designed to manage stress entirely on our own. We are social creatures whose nervous systems evolved within groups. A calm voice can reduce anxiety. A trusted friend can make a difficult situation feel manageable. A supportive therapist can help someone approach experiences that previously felt overwhelming.

This process is known as co-regulation.

Many people assume emotional regulation is something we must achieve independently. While self-regulation is certainly important, humans often learn regulation through relationships first. Children borrow the calm nervous systems of caregivers before developing their own regulation skills. Emotional support animals can similarly comfort us.

As adults many of us continue to rely on connection in much the same way. This helps explain why loneliness, isolation, conflict, and rejection can feel so painful. Our nervous systems interpret social disconnection as a potential threat to survival.

Polyvagal Theory and Mental Health

Polyvagal Theory has become increasingly influential within trauma-informed therapy because it helps explain experiences that traditional models sometimes struggle to capture. Many symptoms can be understood as adaptive responses from a nervous system attempting to keep us safe. Anxiety may reflect mobilisation. Panic may reflect extreme mobilisation. Depression may sometimes involve elements of shutdown. Trauma symptoms may reflect a nervous system that remains highly sensitive to cues of danger. Burnout may involve prolonged mobilisation followed by collapse into shutdown.

This perspective can reduce shame. Instead of asking, "What's wrong with me?" Let’s begin by asking, "What is my nervous system trying to do for me?" That shift can create space for curiosity, compassion, and understanding.

One reason Polyvagal Theory resonates with so many people is that it reflects lived experience. Most people recognise the feeling of being able to think clearly when calm and struggling to think clearly when overwhelmed. Most people recognise the impact that supportive relationships have on their wellbeing, or that their body often reacts before their conscious mind catches up. The theory also highlights something that psychology has increasingly recognised over recent decades.

We do not simply think our way through life.

We experience life through our bodies as well.

Polyvagal Theory has been enormously influential in clinical practice, particularly within trauma-informed care, psychotherapy, and nervous system education. At the same time, it is important to note that aspects of the theory remain debated within the scientific community. While many of its clinical observations are widely supported, some of the specific evolutionary and neurophysiological mechanisms proposed by the theory continue to be examined and discussed by researchers. This is not unusual in psychology or neuroscience. Scientific understanding evolves over time.

Even where researchers disagree about certain mechanisms, many of the practical observations associated with Polyvagal Theory remain consistent with broader evidence on stress physiology, autonomic nervous system functioning, attachment, emotional regulation, and the importance of social connection.

In other words, the map may not be perfect, but many people find it a helpful way of understanding the territory.

A Different Way of Understanding Yourself

Perhaps the greatest gift of Polyvagal Theory is that it invites us to view ourselves with greater compassion. When we understand that our reactions are often the product of a nervous system attempting to protect us, we can become less focused on blame and more interested in understanding. The nervous system is simply doing what it has learned to do in order to survive.

Sometimes it does this brilliantly.

Sometimes it gets things wrong.

Sometimes it reacts to modern life as though it were still preparing us to survive on the savannah thousands of years ago.

Understanding this does not solve every problem but it can help us stop fighting ourselves quite so fiercely.

Therapy can help you better understand your unique nervous system patterns, recognise what moves you into states of safety, activation, or shutdown, and develop practical strategies for responding more effectively. Through therapy, many people discover that healing is not about forcing themselves to be different. It is often about learning how to work with the nervous system they already have. I firmly believe our bodies are telling us how to heal and be happy - often we just need to learn the tools to listen to it.

A downloadable handout of Polyvagal theory can be found here.

References

Dana, D. (2018). The polyvagal theory in therapy: Engaging the rhythm of regulation. W.W. Norton.

Porges, S. W. (2011). The polyvagal theory: Neurophysiological foundations of emotions, attachment, communication, and self-regulation. W.W. Norton.

Porges, S. W. (2021). Polyvagal safety: Attachment, communication, self-regulation. W.W. Norton.

Thayer, J. F., & Lane, R. D. (2009). Claude Bernard and the heart-brain connection: Further elaboration of a model of neurovisceral integration. Neuroscience & Biobehavioral Reviews, 33(2), 81-88.

Yakunina, N., Chen, S., & Schaufeli, W. B. (2022). The relationship between burnout and physiological stress: A systematic review. Frontiers in Psychology, 13, 1017825.