I simplify the theory to emphasize the powerful role that the state of our autonomic nervous system plays in 'mediating' how we interpret and react to the world around us. The theory then makes testable predictions about how specific physiological states lead to different clusters of behaviors and feelings. Ranging from autonomic calmness that would promote accessibility and co-regulation via spontaneous social engagement behaviors, to autonomic activation and potential destabilization that would promote defensive fight/flight reactions, to an autonomic shutdown that would lead to freeze, collapse, or potentially to dissociation. These three clusters are dependent on different autonomic circuits and represent the strategies that evolved from ancient asocial vertebrates to social mammals. With social mammals, sociality functions as a neuromodulator to calm the autonomic state to facilitate the homeostatic functions of health, growth, and restoration.

You can go back to elementary school and visualize feeling embarrassed or not fitting in…. During these situations, your autonomic nervous system moves into a state of threat, and with it, you experience the world as a threatening place and become hypervigilant in an attempt to minimize mistakes that would trigger aggression from others. There are positive examples in which you may enter an environment with a feeling of threat, and through the welcoming engagement of another, you feel safe and can be your expressive self. Note that creativity and problem-solving are similarly affected – compromised when in a state of threat and optimized when in a state of safety.

Polyvagal Theory incorporates both bottom-up and top-down approaches. The theory emphasizes that our thoughts and memories as well as detections of threat and safety in the environment (top-down) and that the bodily feeling through neural pathways from organs to the brain via the process of interoception (bottom-up) complete the feedback circuit. Thus, top-down brain processes influence organs and bottom-up signals from the organs influence brain processes. Polyvagal Theory emphasizes both aspects of an integrated 'feedback' system. Thus, numbing the body (top-down) would disrupt the neural feedback required optimized homeostatic function with resulting end organ damage. This is what we see with survivors of trauma, many of whom have a dysfunctional autonomic nervous system, as evidenced by the prevalence of gut and other autonomic problems.

The theory has been used in peer-reviewed research on depression and has identified a parallel between disruption in vagal regulation of the ANS and severity of depression, specifically distinguishing between bipolar depression and major depression. A google scholar search entering my name and depression should identify the articles.

Theoretically, the theory documents that an autonomic nervous system in a state of threat supports the symptoms that are used to diagnose depression. Polyvagal informed therapies/therapists would approach treatment by acknowledging that their depressed clients' autonomic nervous system is 'retuned' to defense.

Treatments would include strategies in which the client becomes more aware of their own autonomic state and the use of 'neural' exercises to enhance autonomic state regulation with cues of safety and co-regulation.

The easiest portal to access the calming impact of the vagus is to exhale slowly through the nose or through the mouth with parsed lips. The calming effect of the vagus is more accessible during long exhalation and least accessible during long inhalations. Gentle massages of your neck or forehead will stimulate the calming effect as well but through less direct pathways. Singing and chanting are also methods, since the laryngeal and pharyngeal nerves are vagal as well, and singing and chanting require slow exhalations.

There is the possibility of engaging a co-regulatory pet such as a dog or horse, or cat. These social mammals mimic our neuroception of safety and danger and spontaneous co-regulators when there are cues of safety. Also, video conferencing, although not as good as face-to-face interaction, does elicit spontaneous social engagement and a degree of co-regulation.

This is an evolving topic within Polyvagal Theory. To answer this, we need not only to describe the survivor's behavior, but we need to understand the perpetrator's response to the survivor. I and a few of my colleagues are working to define appeasement as an extraordinary capacity to functionally convince and 'co-regulate' the perpetrator. This is not easily accomplished, and I believe few have this resource available to them during life-threatening, challenging times. I think it is a hybrid state in which threat is detected by the survivor, but their social engagement system is still sufficiently resourced to send cues that are an effective co-regulator. I think 'pleasing' objectifies the behavior and does not convey the same 'functional' intentionality that 'appease' does – appease triggers a state in the perpetrator that the survivor is on their team.

Many therapeutic strategies have found that the concepts embedded in polyvagal theory usefully inform them of a neurophysiological substrate consistent with both their trainings and clinical insights. There are a few general ways, 1) read peer-reviewed papers on the theory and applications, use ‘Polyvagal’ to search google scholar, 2) read the books that I have written or those by Deb Dana, especially those currently published by WW Norton and included in their Polyvagal Bookshelf, and 3) take courses or workshops through the Polyvagal Institute (polyvagalinstitute.org) or PESI that I or Deb Dana give. There are also several YouTube interviews and presentations.

Below are links to recent articles in open-access journals. https://www.frontiersin.org/articles/10.3389/fnint.2022.871227/full

https://www.sciencedirect.com/science/article/pii/S2666497621000436

https://journals.lww.com/hrpjournal/Fulltext/9900/Neuromodulation_Using_Computer_Altered_Music_to.5.aspx

https://www.frontiersin.org/articles/10.3389/fpsyt.2022.830926/full

https://www.frontiersin.org/articles/10.3389/fpsyt.2020.577728/full

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8629069/pdf/cn-17-135.pdf

I would explore memories of calmness, especially with loved ones and bonded pets. If they can retrieve a positive, comforting experience, perhaps with their parents, it will give you a starting point on which to expand.