The polyvagal theory

Polyvagal Theory: Understanding Nervous System States at the Heart of Our Emotional Reactions

Polyvagal Theory, developed by neuroscientist Stephen W. Porges, offers a deeper understanding of how the autonomic nervous system influences our emotions, our responses to stress, our sense of safety and the way we connect with others. It provides a valuable perspective on anxiety, trauma, attachment difficulties and, more broadly, the relationship between body and mind.

Some human reactions can seem disproportionate, confusing or difficult to explain through willpower alone. A person may feel overwhelmed by anxiety despite there being no apparent danger, become angry when they had wanted to remain calm, freeze in a stressful situation, or disconnect internally from their emotions.

These responses are not simply the result of poor self-control. They deeply involve the body, the brain and the autonomic nervous system.

Developed by Stephen W. Porges from the 1990s onwards, Polyvagal Theory interprets these experiences through the functioning of the autonomic nervous system—the part of the nervous system that automatically regulates many vital functions, including breathing, heart rate, digestion, alertness, mobilisation and relaxation.

The theory places particular emphasis on the vagus nerve, a major nerve connecting the brain to several organs throughout the body, and on the way the organism continually assesses whether we are safe, in danger or facing a more profound threat.

A Nervous System That Seeks Safety First

One of the central contributions of Polyvagal Theory is the understanding that the nervous system responds not only to what we consciously think, but also to what it perceives, often outside our awareness.

Before we have consciously analysed a situation, the body may already have detected cues of safety or threat: a tone of voice, a facial expression, a silence, tension in the atmosphere, a posture, a gaze or a sense of relational distance.

Stephen Porges introduced the term "neuroception" to describe the nervous system’s capacity to automatically assess the environment, other people and the internal state of the body.

Neuroception is not a conscious thought. It is an implicit form of detection: the body “senses” whether a situation is safe, uncertain or threatening, and then organises the physiological and emotional responses that appear most appropriate.

From this perspective, some emotional reactions are not primarily choices. They are protective responses.

The body is not trying to “behave badly”, “overreact” or “resist”. It is attempting to survive and preserve the person’s psychological and physiological integrity.

Three Main States of the Autonomic Nervous System

Polyvagal Theory generally describes three main modes of autonomic nervous system organisation.

These are not rigid categories, but physiological tendencies that influence the way we feel, think, connect and act.

1. The Ventral Vagal State: Safety, Connection and Relational Openness

When the nervous system detects sufficient safety, the ventral vagal state can support relational openness, curiosity, communication, play, learning, flexible thinking and the ability to feel present with oneself and with others.

In this state, the body does not need to mobilise all its energy for defence.

Relationship itself can become regulating. A gentle voice, an expressive face, a kind gaze, a stable presence or a shared rhythm can help the body regain a sense of safety.

Polyvagal Theory refers here to the “social engagement system”: the interconnected pathways that link bodily regulation with human communication through voice, facial expression, listening, eye contact, breathing, prosody and emotional expression.

Clinically, this state is essential. It supports the therapeutic alliance, the ability to explore one’s history, reflect on inner experience, feel without becoming overwhelmed, and gradually integrate difficult experiences.

2. The Sympathetic State: Mobilisation, Fight or Flight

When the nervous system detects danger, it may activate the sympathetic system.

The body prepares for action: heart rate increases, muscles tense, alertness rises, breathing becomes shallower, and energy is directed towards defence or escape.

This state may appear as anxiety, agitation, irritability, rapid thoughts, or an urge to flee, control or fight.

It is not pathological in itself. In fact, it is essential when action is required.

However, when it becomes chronic or is activated in situations that are no longer objectively dangerous, it can lead to significant distress, including hypervigilance, panic attacks, exhaustion, sleep difficulties and relational problems.

From a polyvagal perspective, the aim is therefore not simply to “calm” the person, but to understand what their nervous system is trying to protect.

3. The Dorsal Vagal State: Immobilisation, Withdrawal or Collapse

When a threat is perceived as too intense, too prolonged or impossible to escape, the nervous system may shift into a state of immobilisation.

Within Polyvagal Theory, this state is often associated with the dorsal branch of the vagus nerve. It may be experienced as disconnection, numbness, emptiness, extreme fatigue, dissociation, collapse or helplessness.

Here again, this is a protective response.

When fighting or fleeing no longer seems possible, the organism may reduce the intensity of experience in order to preserve the person.

This mechanism may be particularly present in traumatic experiences, early relational insecurity, or situations in which a child or adult had no genuine possibility of taking action.

Understanding this state allows us to view certain experiences with less blame:

• “I did nothing.”

• “I let it happen.”

• “I did not react.”

• “I cannot feel anything anymore.”

In many cases, the apparent absence of reaction is in fact a neurophysiological survival response.

A Valuable Perspective on Trauma and Attachment

Polyvagal Theory has had a significant impact in the fields of trauma, attachment, perinatal psychology and body-oriented psychotherapy because it helps connect psychological symptoms with nervous system states.

Following trauma, or in a context of repeated relational insecurity, the nervous system may remain organised around threat.

Even after the danger has passed, the body may continue to behave as though protection were still necessary. Some people feel constantly on alert, others alternate between agitation and collapse, while others struggle to feel fully present within relationships.

This understanding is especially important in children, whose nervous systems develop through relationship.

Babies, and later young children, cannot regulate themselves alone. They first rely on the body, voice, gaze, rhythm and emotional availability of the adults around them.

Regulation begins as co-regulation before gradually becoming an internal capacity.

This perspective is also particularly valuable in perinatal work.

Pregnancy, birth, the postpartum period and the earliest bonds with the baby place intense demands on the body and nervous system.

A mother may feel deeply affected, vulnerable, anxious, hypervigilant or exhausted without this being reducible to simple psychological fragility.

Her organism is moving through a period of major transformation in which relational safety, practical support and the quality of the environment play an essential role.

The Body as a Therapeutic Pathway

Polyvagal Theory invites us not to view psychological suffering solely as mental content to be analysed.

It reminds us that the body plays an active role in the way we experience emotions, relationships and our personal history.

In therapy, this may involve paying attention to very concrete elements: breathing, bodily sensations, movements of activation or withdrawal, tolerance of closeness, the quality of the voice, the pace of sessions, the ability to return to the present, and the cues of safety that help the nervous system avoid becoming overwhelmed.

The aim is not to “force” calm or ask a traumatised person to relax through willpower.

Rather, it is to create the conditions in which the nervous system can gradually perceive that it is no longer alone in the face of danger.

Safety cannot simply be declared. It must be built, felt and experienced.

Regaining a Sense of Inner Safety

Polyvagal Theory reminds us that psychological health does not depend solely on intellectual self-understanding.

It also depends on the ability to feel, within the body, that it is possible to return to a state of sufficient safety.

In therapeutic work, this means learning to recognise internal states, identify what activates the nervous system, notice cues of safety, restore the capacity for presence and connection, and gradually develop a more peaceful relationship with oneself and with others.

The goal is not to remain calm at all times.

A living nervous system naturally moves through different states: mobilisation, rest, alertness, engagement and temporary withdrawal.

The aim is instead to regain flexibility: to become activated without being overwhelmed, to protect oneself without becoming permanently disconnected, to rest without collapsing, and to connect without feeling endangered.

Seen in this way, Polyvagal Theory offers a deeply human perspective.

Behind many symptoms is a nervous system that has tried to protect the person.

Therapy can then become a space in which this protection is recognised and understood, before gradually being transformed into a form of safety that is more stable, embodied and relational.

In my clinical practice, Polyvagal Theory provides an essential framework for understanding how the nervous system influences emotions, behaviours and relationships.

It informs, in particular, my use of Lifespan Integration and, when appropriate, the Safe and Sound Protocol (SSP), two approaches that aim to support nervous system regulation and the integration of difficult or traumatic experiences.

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