Polyvagal Theory: Recent Developments in the Science of Emotional Regulation

In this short article, Professor Andrew McDonnell discusses a recent paper on polyvagal theory, and its implications for practice in the caring professions.

Stephen W. Porges is an American psychologist and Professor of Psychiatry at the University of North Carolina. Porges is also currently the Director of the Kinsey Institute Traumatic Stress Research Consortium at Indiana University, studying the effects and impact of trauma.

Porges developed polyvagal theory in 1994, a concept which I apply in my own work to look at stress, trauma, and regulation. Polyvagal theory relates to the structure and function of the two efferent branches of the vagus cranial nerve, which originate from the medulla in the brain.

Each branch is claimed to be associated with a different adaptive behavioral strategy; the ventral branches being restful and the dorsal ones more active in nature.

According to this theory, the nervous system operates on three distinct principles which determine its impact on the body.

Firstly, the autonomic nervous system is a hierarchical one, which reacts to stimuli by activating hierarchical responses in a particular order.

Second, the principle of neuroception applies to the human nervous system, whereby cognition without awareness triggers a reaction in the body. This can be due to a perceived threat or stimulus that is not activated by the conscious brain.

And finally, co-regulation – a state of feeling safe and regulated with another person – can help to de-activate and the autonomic nervous system once it is in distress. However, this can be difficult to achieve, especially for highly stressed and traumatised people.

Polyvagal theory has become an increasingly important phenomenon. A recent review for Frontiers in Psychology explores how polyvagal theory can serve as a foundational theory and support the creative arts and psychomotor therapies for emotional regulation in stress and trauma (Haeyen, 2024).

The increasingly emphasis on arousal regulation and co-regulation is also a relevant and exciting area of research for practitioners. My own experience has found that staff who experience stress and burnout – particularly those working with traumatised individuals – would themselves benefit from stress management skills (Rippon et al., 2020), particularly cardiac exercise, mindfulness, time management, and relaxation techniques. By being better regulated and managing our own stress, we may have a positive impact on repairing trauma for others through co-regulation.

Polyvagal theory can also be linked to my own research on the Low Arousal Approach to managing behaviours. Co-regulation is a central part of the Low Arousal Approach to behaviour, which requires us to be reflective in our approaches. Overall, I find Porges’ work to be intriguing, and still in its relatively early developmental stages. I would encourage individuals who work with people who are traumatised and stressed to read the article below and reflect on their own practice.

By Professor Andrew McDonnell

Clinical Psychologist and CEO to Studio III

Written May 2025

References

Haeyen, Susan. (2024). Frontiers in Psychology, 15. DOI: 10.3389/fpsyg.2024.1382007.