The Polyvagal Theory

In his polyvagal theory, Dr. Stephen Porges argues that humans have a subconscious scanning system that interprets signs of danger that they perceive without even realizing it.
The Polyvagal Theory

Last update: 22 May, 2020

You probably aren’t aware of many of the unconscious processes that happen in your body and mind. The polyvagal theory attempts to explain one of those intuitive processes.

You’ve probably experienced moments when you feel like you’re in danger but there’s no obvious reason for it. Although you feel threatened, no one else around you seems bothered by anything in particular.

Every day, you read social signs of all kinds. When you interact with other people, you unconsciously pick up on facial expressions, body language, and tones of voice. While your body and brain are interpreting these signs, the signs and your surroundings are also shaping your sense of self.

The information that your body processes through these signals tells you who you can trust and who you can’t. You interpret who or what could be a threat and then respond.

A woman with her back to her husband.

Neuroception and the polyvagal theory

Dr. Stephen Porges developed the polyvagal theory, which describes the process by which neural circuits are capable of reading danger signs in your surroundings as “neuroception”. Neuroception is what makes you involuntarily explore people and your surroundings to determine if they’re safe or if they’re a threat.

This is a completely unconscious process that happens in the autonomous nervous system. Just as you breathe without any voluntary effort, you perceive the signs around you automatically.

Scanning your surroundings

This involuntary scan for potential danger happens from birth. It’s extremely important for your survival. Your body is designed to observe, process, and respond to what’s going on around you.

Babies respond to feelings of danger, safety, or closeness to their parents. It happens from the moment you’re born, and you spend the rest of your life unconsciously scanning and evaluating these signs of danger or safety.

Three levels of response development

Within the polyvagal theory, Porges describes three evolutionary stages. The theory argues that the interaction between the sympathetic and parasympathetic nervous systems isn’t just a question of balance. Porges believes that a hierarchy of responses is part of the autonomous nervous system. He argues that the responses happen in three steps:

  • Immobilization. This is the most basic step. The immobilization response to signs of danger involves the vagus nerve. The dorsal part of the nerve responds to signs of extreme danger and immobilizes you completely. It’s as if your parasympathetic nervous system activated at full speed and the body’s response freezes you to the spot.
  • Mobilization. This response comes from the sympathetic nervous system, which is what helps you mobilize during dangerous situations. It’s a way to fight back against a threat.
  • Social commitment. This is the last step and the last response that humans develop in the hierarchy. It responds to the ventral side of the lower nerve that’s part of the nerve that responds to feelings of safety and connection. Social commitment is a process that allows you to feel anchored in feelings of safety and peace.
The polyvagal theory.

The impact of trauma

For people who have experienced trauma, especially when immobilization was an important part of the event, your ability to scan your environment for signs of danger can be severely distorted.

One of the functions of the system, according to the polyvagal theory, is that you won’t end up in a vulnerable position again. Consequently, the body acts to avoid it. As a result, you might be much more sensitive to the signs around you, perceiving a threat where there isn’t one.

Thus, many inoffensive or benign signs could be interpreted as threatening by someone who has been through trauma. A change in facial expression, a tone of voice, or certain body language can trigger an unconscious defensive response.

The vagus nerve and the polyvagal theory

Your vagus nerve plays a role in many parts of your body. It has a significant influence on the cranial nerves that regulate social commitment through facial expression and vocalization.

Human beings long for safety and trust in their interactions with other people. We quickly learn to interpret the signs that tell us we aren’t safe. Consequently, it’ll be easier for you to establish healthy and quality connections with other people.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


  • Clarke, Jodi (2019) Polyvagal Theory and How It Relates to Social Cues. How the Body and Brain Are Impacted by Your Environment. Verywell Mind

  • Porges S. W. (2009). The polyvagal theory: new insights into adaptive reactions of the autonomic nervous system. Cleveland Clinic journal of medicine, 76 Suppl 2(Suppl 2), S86–S90. doi:10.3949/ccjm.76.s2.17

  • Maercker, A., & Hecker, T. (2016). Broadening perspectives on trauma and recovery: a socio-interpersonal view of PTSD. European journal of psychotraumatology, 7, 29303. doi:10.3402/ejpt.v7.29303


This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.